記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1088/1757-899x/1051/1/012086

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier  

DOI： 10.1016/j.wpe.2020.101553

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier  

DOI： 10.1016/j.supflu.2020.104776

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Taylor & Francis  

DOI： 10.1080/00268976.2019.1671618

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier  

DOI： 10.1016/j.fluid.2019.03.017

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：中央大学  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society  

DOI： 10.1080/00268976.2019.1671618

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：MDPI publishers  

DOI： 10.3390/molecules24193572

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier  

DOI： 10.1016/j.molliq.2019.111849

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier  

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総ページ数：359   担当ページ：141-157   記述言語：日本語   著書種別：学術書

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総ページ数：170   記述言語：日本語   著書種別：学術書

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総ページ数：226   担当ページ：20   記述言語：英語   著書種別：学術書

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総ページ数：226   記述言語：英語   著書種別：学術書

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担当ページ：423-448   記述言語：英語   著書種別：学術書

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総ページ数：237   担当ページ：12   記述言語：日本語   著書種別：学術書

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総ページ数：175   担当ページ：145-151   記述言語：日本語   著書種別：学術書

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総ページ数：537   担当ページ：75-81   記述言語：英語   著書種別：学術書

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担当ページ：38-43   記述言語：日本語   著書種別：学術書

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担当ページ：676-680   記述言語：日本語   著書種別：学術書

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担当ページ：286-291   記述言語：日本語   著書種別：学術書

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担当ページ：139-158   記述言語：日本語   著書種別：学術書

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Retention factors for two enantiomers of trans-stilbene oxide, k(1) and k(2), were measured with a chiral AD-H column using two syringe pumps to feed CO2 and methanol as a co-solvent at various temperatures, pressures and co-solvent mole fractions to determine the effects of these operating conditions on the retention factors. The retention factors k(1) and k(2) are for the (R,R)- and (S,S)-forms, respectively. When the isothermal compressibilities of a mixture of CO2 and MeOH were lower than 0.01, far from the critical locus of the CO2 and methanol mixture, both retention factors were well expressed with the solvent density and temperature with an average absolute relative deviation of 1-2%. In the vicinity of the critical locus, however, where the isothermal compressibilities were much larger than 0.01, the relationship between retention factor and density was complicated. Both retention factors were proportional to the isothermal compressibility, irrespective of methanol mole fraction at each temperature. (c) 2017 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2017.10.029

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Carbon dioxide (CO2) solubility was measured in aqueous solutions containing 0.6 wt% D(+)-galacturonic acid (GalH) or sodium D(+)-galacturonate (GalNa) by use of a recirculating apparatus at 313.4 K and at pressures up to 9.29 MPa. The solubilities of CO2 in the two solutions containing Gales or GalNa were similar to those in pure water. The experimental data were correlated with the Peng-Robinson-Stryjek-Vera (PRSV) equation of state. A new method was developed to estimate pH by use of the molar volume from the PRSV equation and compared with measured pH values. It gives some idea of the quantitative agreement between the equation of states and the measured pH values over the same range of conditions. (C) 2017 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2017.03.005

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Carbon dioxide (CO2) solubility was measured in aqueous solutions containing 0.6 wt% D(+)-galacturonic acid (GalH) or sodium D(+)-galacturonate (GalNa) by use of a recirculating apparatus at 313.4 K and at pressures up to 9.29 MPa. The solubilities of CO2 in the two solutions containing Gales or GalNa were similar to those in pure water. The experimental data were correlated with the Peng-Robinson-Stryjek-Vera (PRSV) equation of state. A new method was developed to estimate pH by use of the molar volume from the PRSV equation and compared with measured pH values. It gives some idea of the quantitative agreement between the equation of states and the measured pH values over the same range of conditions. (C) 2017 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2017.03.005

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記述言語：英語   出版者・発行元：ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD  

The diffusion coefficients of chromium(III) acetylacetonate (Cr(acac)(3)) were measured at infinite dilution in supercritical carbon dioxide and in liquid ethanol. The diffusion measurements in supercritical carbon dioxide were carried out at five different temperatures varying from T= (308.15 to 343.15) K and at pressures up to 40.00 MPa by using the chromatographic impulse response (CIR) method. And the measurements in liquid ethanol were also made by the Taylor dispersion method at five temperatures in the range from T= (299.15 to 333.15) K and 0.10 MPa. The determined diffusion activation energies in supercritical carbon dioxide were E-a = (22.9-11.2) kJ.mol(-1) at p = (13.00-35.00) MPa, respectively, and that in liquid ethanol was 15.9 kJ.mol(-1) at 0.10 MPa. All the diffusion coefficients of Cr(acac)(3) in supercritical and in liquid states can be correlated by the hydrodynamic equation as a function of temperature and fluid viscosity with average absolute relative deviation (AARD) of 4.6% over a wide viscosity range from eta = (3.036.10(-5) to 1.113.10(-3)) Pa.s for 85 data points. (C) 2016 Elsevier Ltd.

DOI： 10.1016/j.jct.2016.10.012

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記述言語：英語   出版者・発行元：ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD  

The diffusion coefficients of chromium(III) acetylacetonate (Cr(acac)(3)) were measured at infinite dilution in supercritical carbon dioxide and in liquid ethanol. The diffusion measurements in supercritical carbon dioxide were carried out at five different temperatures varying from T= (308.15 to 343.15) K and at pressures up to 40.00 MPa by using the chromatographic impulse response (CIR) method. And the measurements in liquid ethanol were also made by the Taylor dispersion method at five temperatures in the range from T= (299.15 to 333.15) K and 0.10 MPa. The determined diffusion activation energies in supercritical carbon dioxide were E-a = (22.9-11.2) kJ.mol(-1) at p = (13.00-35.00) MPa, respectively, and that in liquid ethanol was 15.9 kJ.mol(-1) at 0.10 MPa. All the diffusion coefficients of Cr(acac)(3) in supercritical and in liquid states can be correlated by the hydrodynamic equation as a function of temperature and fluid viscosity with average absolute relative deviation (AARD) of 4.6% over a wide viscosity range from eta = (3.036.10(-5) to 1.113.10(-3)) Pa.s for 85 data points. (C) 2016 Elsevier Ltd.

DOI： 10.1016/j.jct.2016.10.012

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記述言語：英語   出版者・発行元：ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD  

The diffusion coefficients of chromium(III) acetylacetonate (Cr(acac)(3)) were measured at infinite dilution in supercritical carbon dioxide and in liquid ethanol. The diffusion measurements in supercritical carbon dioxide were carried out at five different temperatures varying from T= (308.15 to 343.15) K and at pressures up to 40.00 MPa by using the chromatographic impulse response (CIR) method. And the measurements in liquid ethanol were also made by the Taylor dispersion method at five temperatures in the range from T= (299.15 to 333.15) K and 0.10 MPa. The determined diffusion activation energies in supercritical carbon dioxide were E-a = (22.9-11.2) kJ.mol(-1) at p = (13.00-35.00) MPa, respectively, and that in liquid ethanol was 15.9 kJ.mol(-1) at 0.10 MPa. All the diffusion coefficients of Cr(acac)(3) in supercritical and in liquid states can be correlated by the hydrodynamic equation as a function of temperature and fluid viscosity with average absolute relative deviation (AARD) of 4.6% over a wide viscosity range from eta = (3.036.10(-5) to 1.113.10(-3)) Pa.s for 85 data points. (C) 2016 Elsevier Ltd.

DOI： 10.1016/j.jct.2016.10.012

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記述言語：英語   出版者・発行元：Elsevier  

DOI： 10.1016/j.jct.2016.10.012

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Three cellulosic samples (CP, cellulose powder; CC, cotton cellulose; FP, filter paper) were subjected to liquid water at 493 to 553 K and 10 MPa in a semibatch reactor. The solubilization rates based on the total organic carbon (TOC) yield were determined as first order reaction kinetics, and the rates for CP were 2-4 times higher than those for CC and FP. The yields of the products, such as glucose, cellooligosaccharides with degrees of polymerization (DP) from 2 to 9, fructose, 5-(hydroxymethyl)furfural, and levoglucosan, were proportional to the TOC of the products over nearly the entire range of conversion, irrespective of the reaction temperature. The slopes in the plots of the product yield versus TOC yield were correlated with DP of up to 9, and the correlations for CP, CC, and FP were consistent and independent of the temperature and cellulose species.

DOI： 10.1021/acs.iecr.6b01782

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

A novel catalytic property of CeO2 and its nanocrystals is discovered, and a simple chemical recycling technique for the conversion of poly(bisphenol A) carbonate (PC) to the contexture monomer (bisphenol A) under hydro thermal conditions in the presence of heterogeneous CeO2 catalyst using a batch reactor is proposed. The PC is completely depolymerized under these conditions in the presence of large CeO2 crystal with 75 nm crystallite size at 200 degrees C for 5 h. When CeO2 nanocrystals approximately 7.4 nm crystallite size are used, the catalyst amount, reaction temperature, and time required to completely depolymerize the PC are reduced compared with the experimental conditions using large crystal; the maximum monomer (bisphenol A) yield is approximately 90%. The depolymerization reaction of PC correlates directly with the surface-to-volume ratio. Further decomposition of the monomer is inhibited by reducing and/or controlling the amount of the catalyst, reaction temperature, and time. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.catcom.2016.06.009

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

A novel catalytic property of CeO2 and its nanocrystals is discovered, and a simple chemical recycling technique for the conversion of poly(bisphenol A) carbonate (PC) to the contexture monomer (bisphenol A) under hydro thermal conditions in the presence of heterogeneous CeO2 catalyst using a batch reactor is proposed. The PC is completely depolymerized under these conditions in the presence of large CeO2 crystal with 75 nm crystallite size at 200 degrees C for 5 h. When CeO2 nanocrystals approximately 7.4 nm crystallite size are used, the catalyst amount, reaction temperature, and time required to completely depolymerize the PC are reduced compared with the experimental conditions using large crystal; the maximum monomer (bisphenol A) yield is approximately 90%. The depolymerization reaction of PC correlates directly with the surface-to-volume ratio. Further decomposition of the monomer is inhibited by reducing and/or controlling the amount of the catalyst, reaction temperature, and time. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.catcom.2016.06.009

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Three cellulosic samples (CP, cellulose powder; CC, cotton cellulose; FP, filter paper) were subjected to liquid water at 493 to 553 K and 10 MPa in a semibatch reactor. The solubilization rates based on the total organic carbon (TOC) yield were determined as first order reaction kinetics, and the rates for CP were 2-4 times higher than those for CC and FP. The yields of the products, such as glucose, cellooligosaccharides with degrees of polymerization (DP) from 2 to 9, fructose, 5-(hydroxymethyl)furfural, and levoglucosan, were proportional to the TOC of the products over nearly the entire range of conversion, irrespective of the reaction temperature. The slopes in the plots of the product yield versus TOC yield were correlated with DP of up to 9, and the correlations for CP, CC, and FP were consistent and independent of the temperature and cellulose species.

DOI： 10.1021/acs.iecr.6b01782

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記述言語：日本語   出版者・発行元：日本生物工学会  

CiNii Books

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The infinite dilution binary diffusion coefficients D-12 for aluminum acetylacetonate in supercritical CO2 were determined at 308.15-333.15 K and at 7.80-40.00 MPa by the chromatographic impulse response (CIR) method. And, the diffusion measurements in liquid ethanol were carried out at 300.15-333.15 K and at 0.10 and 30.00 MPa by the Taylor dispersion method. It was found that the D-12 values measured in supercritical CO2 show slowing down in the region of near critical point. The determined activation energies of diffusion were 23.0, 13.7, 12.0, 11.3 kJ/mol at 12.00, 20.00, 25.00, 35.00 MPa in supercritical CO2 and 19.1 kJ/mol at 0.10 MPa in liquid ethanol, respectively. All determined 90 diffusion data in this study can be correlated with the equation of D-12 [m(2)/S] = 1.558 x 10(-14) T [K] eta [Pa s](-0.761) with average absolute relative deviation (AARD) of 5.6% over a wide fluid viscosity range from 2.462 x 10(-5) to 1.258 x 10(-3) Pa s. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2016.01.042

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The infinite dilution binary diffusion coefficients D-12 for aluminum acetylacetonate in supercritical CO2 were determined at 308.15-333.15 K and at 7.80-40.00 MPa by the chromatographic impulse response (CIR) method. And, the diffusion measurements in liquid ethanol were carried out at 300.15-333.15 K and at 0.10 and 30.00 MPa by the Taylor dispersion method. It was found that the D-12 values measured in supercritical CO2 show slowing down in the region of near critical point. The determined activation energies of diffusion were 23.0, 13.7, 12.0, 11.3 kJ/mol at 12.00, 20.00, 25.00, 35.00 MPa in supercritical CO2 and 19.1 kJ/mol at 0.10 MPa in liquid ethanol, respectively. All determined 90 diffusion data in this study can be correlated with the equation of D-12 [m(2)/S] = 1.558 x 10(-14) T [K] eta [Pa s](-0.761) with average absolute relative deviation (AARD) of 5.6% over a wide fluid viscosity range from 2.462 x 10(-5) to 1.258 x 10(-3) Pa s. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2016.01.042

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The infinite dilution binary diffusion coefficients D-12 for aluminum acetylacetonate in supercritical CO2 were determined at 308.15-333.15 K and at 7.80-40.00 MPa by the chromatographic impulse response (CIR) method. And, the diffusion measurements in liquid ethanol were carried out at 300.15-333.15 K and at 0.10 and 30.00 MPa by the Taylor dispersion method. It was found that the D-12 values measured in supercritical CO2 show slowing down in the region of near critical point. The determined activation energies of diffusion were 23.0, 13.7, 12.0, 11.3 kJ/mol at 12.00, 20.00, 25.00, 35.00 MPa in supercritical CO2 and 19.1 kJ/mol at 0.10 MPa in liquid ethanol, respectively. All determined 90 diffusion data in this study can be correlated with the equation of D-12 [m(2)/S] = 1.558 x 10(-14) T [K] eta [Pa s](-0.761) with average absolute relative deviation (AARD) of 5.6% over a wide fluid viscosity range from 2.462 x 10(-5) to 1.258 x 10(-3) Pa s. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2016.01.042

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Infinite dilution binary diffusion coefficients (D-12) of two dyestuffs, disperse blue 14 (DB14) and disperse orange 11 (DO11), were measured in supercritical CO2 at 310-330 K and up to 35 MPa by the chromatographic impulse response (CIR) method and in liquid methanol and ethanol at 308-328 K and atmospheric pressure by the Taylor dispersion method. The retention factors (k) were also measured by the CIR method. The diffusion coefficients were well represented by a hydrodynamic equation, as a function of temperature and solvent viscosity, over a wide range of solvent viscosity from scCO(2) to liquid solvents with average absolute relative deviations (AARDs) of 1.7% and 2.6% for 63 and 93 data points of DB14 and DO11, respectively. The solubility data for the two dyestuffs reported in the literature were well correlated with solute retention factor measured in the present study and solvent density with AARD of 7.05% for DB 14 of 109 data points and that of 15.4% for DO11 of 43 data points. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2016.01.010

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Infinite dilution binary diffusion coefficients (D-12) of two dyestuffs, disperse blue 14 (DB14) and disperse orange 11 (DO11), were measured in supercritical CO2 at 310-330 K and up to 35 MPa by the chromatographic impulse response (CIR) method and in liquid methanol and ethanol at 308-328 K and atmospheric pressure by the Taylor dispersion method. The retention factors (k) were also measured by the CIR method. The diffusion coefficients were well represented by a hydrodynamic equation, as a function of temperature and solvent viscosity, over a wide range of solvent viscosity from scCO(2) to liquid solvents with average absolute relative deviations (AARDs) of 1.7% and 2.6% for 63 and 93 data points of DB14 and DO11, respectively. The solubility data for the two dyestuffs reported in the literature were well correlated with solute retention factor measured in the present study and solvent density with AARD of 7.05% for DB 14 of 109 data points and that of 15.4% for DO11 of 43 data points. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2016.01.010

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

In the present study, the diffusion coefficients (D) of vitamin K-3 (2-methyl-1,4-naphthalenedione) in carbon dioxide-expanded liquid methanol were measured by the Taylor dispersion method close to the gas liquid saturation line at 313.2 K over nearly the entire range of carbon dioxide mole fractions (xCO(2)) from zero (pure methanol) to 0.89. Although the D values simply increased with increasing CO2 mole fractions when increasing the pressure, similar to the behavior of the expansion coefficients, there were two unique regions with respect to solvent density: from xCO(2) = 0 to ca. 0.44 (corresponding to the almost maximum solvent density at 313.2 K) and from this density to the critical point of the mixture. In the former region, the D values increased with increasing pressure (while the solvent density also increased) and in the latter region D increased with decreasing solvent density, while the density also decreased with increasing pressure or xCO(2). The resulting D values were less than those predicted by the hydrodynamic equation when using two constants determined for vitamin K-3 in supercritical CO2 and in organic solvents. The relative differences of diffusion coefficients, representing the deviations from the hydrodynamic equation, were almost proportional to the excess viscosity values. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2015.10.012

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

In the present study, the diffusion coefficients (D) of vitamin K-3 (2-methyl-1,4-naphthalenedione) in carbon dioxide-expanded liquid methanol were measured by the Taylor dispersion method close to the gas liquid saturation line at 313.2 K over nearly the entire range of carbon dioxide mole fractions (xCO(2)) from zero (pure methanol) to 0.89. Although the D values simply increased with increasing CO2 mole fractions when increasing the pressure, similar to the behavior of the expansion coefficients, there were two unique regions with respect to solvent density: from xCO(2) = 0 to ca. 0.44 (corresponding to the almost maximum solvent density at 313.2 K) and from this density to the critical point of the mixture. In the former region, the D values increased with increasing pressure (while the solvent density also increased) and in the latter region D increased with decreasing solvent density, while the density also decreased with increasing pressure or xCO(2). The resulting D values were less than those predicted by the hydrodynamic equation when using two constants determined for vitamin K-3 in supercritical CO2 and in organic solvents. The relative differences of diffusion coefficients, representing the deviations from the hydrodynamic equation, were almost proportional to the excess viscosity values. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2015.10.012

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記述言語：英語   出版者・発行元：Elsevier  

The influence of the crystal structure on the physical properties of monoclinic ZrO2 nanocrystals is investigated by an annealing treatment. Monoclinic ZrO2 nanocrystals with diameters of approximately 20 nm are synthesized by a hydrothermal method using subcritical water. The nanocrystals have chemisorbed water molecules, hydroxides and nitro groups on their surfaces. The crystallographic structures are reformed by annealing the nanocrystals at 800 °C for 5 h. This treatment causes the crystallite sizes to increase, the crystal lattice to shrink and some of the molecules chemisorbed on the surfaces to be lost. The annealing treatment leads to there being fewer lattice defects, and to the modification of surface characteristics of the nanocrystals. The treatment also changes the optical absorption characteristics of the nanocrystals. The magnetic moments caused by lattice defects are identified.

DOI： 10.1016/j.nanoso.2015.03.001

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記述言語：英語   出版者・発行元：Elsevier  

The influence of the crystal structure on the physical properties of monoclinic ZrO2 nanocrystals is investigated by an annealing treatment. Monoclinic ZrO2 nanocrystals with diameters of approximately 20 nm are synthesized by a hydrothermal method using subcritical water. The nanocrystals have chemisorbed water molecules, hydroxides and nitro groups on their surfaces. The crystallographic structures are reformed by annealing the nanocrystals at 800 °C for 5 h. This treatment causes the crystallite sizes to increase, the crystal lattice to shrink and some of the molecules chemisorbed on the surfaces to be lost. The annealing treatment leads to there being fewer lattice defects, and to the modification of surface characteristics of the nanocrystals. The treatment also changes the optical absorption characteristics of the nanocrystals. The magnetic moments caused by lattice defects are identified.

DOI： 10.1016/j.nanoso.2015.03.001

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記述言語：英語   出版者・発行元：Elsevier B.V.  

The infinite dilution binary diffusion coefficients D12 for aluminum acetylacetonate in supercritical CO2 were determined at 308.15–333.15 K and at 7.80–40.00 MPa by the chromatographic impulse response (CIR) method. And, the diffusion measurements in liquid ethanol were carried out at 300.15–333.15 K and at 0.10 and 30.00 MPa by the Taylor dispersion method. It was found that the D12 values measured in supercritical CO2 show slowing down in the region of near critical point. The determined activation energies of diffusion were 23.0, 13.7, 12.0, 11.3 kJ/mol at 12.00, 20.00, 25.00, 35.00 MPa in supercritical CO2 and 19.1 kJ/mol at 0.10 MPa in liquid ethanol, respectively. All determined 90 diffusion data in this study can be correlated with the equation of D12 [m2/s] = 1.558 Ã&#151
 10−14 T [K] η [Pa s]−0.761 with average absolute relative deviation (AARD) of 5.6% over a wide fluid viscosity range from 2.462 Ã&#151
 10−5 to 1.258 Ã&#151
 10−3 Pa s.

DOI： 10.1016/j.fluid.2016.01.042

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DOI： 10.4131/jshpreview.25.208

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The infinite dilution binary diffusion coefficients D-12 of lithium acetylacetonate were measured in supercritical carbon dioxide by the chromatographic impulse response (CIR) method at 308.15-333.15K and pressures up to 36.00 MPa. The D-12 values were also measured in liquid ethanol at 298.15-333.15K, and at 0.10, 10.00 and 30.00 MPa by the Taylor dispersion method. The effects of temperature, pressure and density of fluid on D-12 values were studied. The D-12 data increased from 1.140 x 10(-9) m(2) s(-1) in liquid ethanol at 298.15K and 30.00 MPa to 2.218 x 10(-8) m(2) s(-1) in supercritical carbon dioxide at 333.15 K and 14.00 MPa. It was observed that the D-12 data in supercritical carbon dioxide at 15.00, 20.00 and 30.00 MPa can be well correlated as a function of temperature using an Arrhenius type equation, which provided the diffusion activation energies of 17.5, 13.4 and 11.0 kJ mol(-1); that in liquid ethanol at 0.10,10.00,30.00 MPa gave the diffusion activation energies of 14.0, 14.2 and 13.8 kJ mol(-1), respectively. It was found that the proposed correlation based on hydrodynamic approach can well represent all the measured D-12 data of lithium acetylacetonate in supercritical carbon dioxide and in liquid ethanol with the average absolute relative deviation (AARD) of 1.7% for 88 data points. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2015.07.003

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The infinite dilution binary diffusion coefficients D-12 of lithium acetylacetonate were measured in supercritical carbon dioxide by the chromatographic impulse response (CIR) method at 308.15-333.15K and pressures up to 36.00 MPa. The D-12 values were also measured in liquid ethanol at 298.15-333.15K, and at 0.10, 10.00 and 30.00 MPa by the Taylor dispersion method. The effects of temperature, pressure and density of fluid on D-12 values were studied. The D-12 data increased from 1.140 x 10(-9) m(2) s(-1) in liquid ethanol at 298.15K and 30.00 MPa to 2.218 x 10(-8) m(2) s(-1) in supercritical carbon dioxide at 333.15 K and 14.00 MPa. It was observed that the D-12 data in supercritical carbon dioxide at 15.00, 20.00 and 30.00 MPa can be well correlated as a function of temperature using an Arrhenius type equation, which provided the diffusion activation energies of 17.5, 13.4 and 11.0 kJ mol(-1); that in liquid ethanol at 0.10,10.00,30.00 MPa gave the diffusion activation energies of 14.0, 14.2 and 13.8 kJ mol(-1), respectively. It was found that the proposed correlation based on hydrodynamic approach can well represent all the measured D-12 data of lithium acetylacetonate in supercritical carbon dioxide and in liquid ethanol with the average absolute relative deviation (AARD) of 1.7% for 88 data points. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2015.07.003

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記述言語：英語   出版者・発行元：InTech  

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Cellulose in a filter paper is hydrolyzed by six dilute organic acids (0.01-1 wt %) under hydrothermal conditions (260 degrees C and 5 MPa) using a semibatch reactor. The rate of degradation increases with an increase in the concentration of the acid. The cellulose sample is completely degraded by the acids (1 wt %) in 60 min. While the yields of the different products are dependent on the nature of the organic acid used, cellulose is essentially converted to mono- and oligosaccharides, with glucose as the major product. The observed increase in the rate of degradation in the presence of formic or citric acid at 1 wt % allows for the degradation of the cellulose sample in a short time (20 min) and results in the highest yield of glucose (approximately 60%) observed in this study. The rate of conversion of the cellulose sample to glucose correlates directly with [H+].

DOI： 10.1021/acs.iecr.5b00920

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Cellulose in a filter paper is hydrolyzed by six dilute organic acids (0.01-1 wt %) under hydrothermal conditions (260 degrees C and 5 MPa) using a semibatch reactor. The rate of degradation increases with an increase in the concentration of the acid. The cellulose sample is completely degraded by the acids (1 wt %) in 60 min. While the yields of the different products are dependent on the nature of the organic acid used, cellulose is essentially converted to mono- and oligosaccharides, with glucose as the major product. The observed increase in the rate of degradation in the presence of formic or citric acid at 1 wt % allows for the degradation of the cellulose sample in a short time (20 min) and results in the highest yield of glucose (approximately 60%) observed in this study. The rate of conversion of the cellulose sample to glucose correlates directly with [H+].

DOI： 10.1021/acs.iecr.5b00920

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記述言語：英語   出版者・発行元：SOC CHEMICAL ENG JAPAN  

Poly(ethylene naphthalate) (PEN) pellets were converted to monomers (naphthalene dicarboxylic acid (NDC) and ethylene glycol (EG)) in an aqueous amine solution under hydrothermal conditions using a small semi-batch reactor. Three amines (methylamine, dimethylamine, and trimethylamine) were evaluated as reactants for depolymerization of PEN and compared with ammonia. The total yield of both monomers (NDC + EG) on the basis of the carbon mass of the initial PEN pellets, at 493 K and 5.0 MPa, for a reaction time of 50 min, using an amine concentration of 0.6 mol/kg was highest with trimethylamine (97.2%) followed by methylamine (86.6%) and dimethylamine (89.8%) in succession. The differences in the total yields resulted primarily from the differences in the NDC yields, and were affected by the amine species, although the EG yield was similar with all amines. The yields were higher than 95% of the theoretical value with all evaluated amines. The difference in the yields may be affected by the stabilities of the intermediate products with the primary and secondary amines in the aqueous solutions. The reaction rates with respect to the unreacted mass of PEN were represented by the surface reaction model, i.e., 2/3rd order reaction kinetics, as previously observed for poly(ethylene terephthalate) in aqueous solutions of ammonia and amine at low concentrations. The apparent rate constant from the surface reaction model was proportional to the amine concentration.

DOI： 10.1252/jcej.14we065

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記述言語：英語   出版者・発行元：SPRINGER  

Complexation characteristics of 1,4,7,10,13,16-hexaoxacyclooctadecane (18-crown-6, 18C6) with Li+ and K+ in a hydrophobic ionic liquid of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl) amide under dry and humid conditions at 298.2 K were studied by H-1 and C-13 NMR chemical shifts. The comparison of the H-1 and C-13 chemical shifts of 18C6 molecule between the dry and humid IL solutions without the alkali metal ions showed that uncomplexed 18C6 molecules are solvated by water molecules in the humid ionic liquid solution. The changes in the H-1 and C-13 chemical shifts of 18C6 ligand molecule with the increases in the Li+ and K+ concentrations revealed that in both dry and humid ionic liquid solutions 18C6 molecule forms 1:1 complexes with Li+ and K+. The H-1 NMR data of water molecules in the humid ionic liquid solutions demonstrated that water molecules interact with Li+-18C6 complexes and free Li+, but do not with K+-18C6 complexes and free K+. The mechanisms of the formation of the Li+ and K+ complexes in the humid ionic liquid solution are different from each other due to the differences in the complex-water interactions.

DOI： 10.1007/s10847-014-0427-1

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記述言語：英語   出版者・発行元：SPRINGER  

Complexation characteristics of 1,4,7,10,13,16-hexaoxacyclooctadecane (18-crown-6, 18C6) with Li+ and K+ in a hydrophobic ionic liquid of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl) amide under dry and humid conditions at 298.2 K were studied by H-1 and C-13 NMR chemical shifts. The comparison of the H-1 and C-13 chemical shifts of 18C6 molecule between the dry and humid IL solutions without the alkali metal ions showed that uncomplexed 18C6 molecules are solvated by water molecules in the humid ionic liquid solution. The changes in the H-1 and C-13 chemical shifts of 18C6 ligand molecule with the increases in the Li+ and K+ concentrations revealed that in both dry and humid ionic liquid solutions 18C6 molecule forms 1:1 complexes with Li+ and K+. The H-1 NMR data of water molecules in the humid ionic liquid solutions demonstrated that water molecules interact with Li+-18C6 complexes and free Li+, but do not with K+-18C6 complexes and free K+. The mechanisms of the formation of the Li+ and K+ complexes in the humid ionic liquid solution are different from each other due to the differences in the complex-water interactions.

DOI： 10.1007/s10847-014-0427-1

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記述言語：英語   出版者・発行元：SOC CHEMICAL ENG JAPAN  

Poly(ethylene naphthalate) (PEN) pellets were converted to monomers (naphthalene dicarboxylic acid (NDC) and ethylene glycol (EG)) in an aqueous amine solution under hydrothermal conditions using a small semi-batch reactor. Three amines (methylamine, dimethylamine, and trimethylamine) were evaluated as reactants for depolymerization of PEN and compared with ammonia. The total yield of both monomers (NDC + EG) on the basis of the carbon mass of the initial PEN pellets, at 493 K and 5.0 MPa, for a reaction time of 50 min, using an amine concentration of 0.6 mol/kg was highest with trimethylamine (97.2%) followed by methylamine (86.6%) and dimethylamine (89.8%) in succession. The differences in the total yields resulted primarily from the differences in the NDC yields, and were affected by the amine species, although the EG yield was similar with all amines. The yields were higher than 95% of the theoretical value with all evaluated amines. The difference in the yields may be affected by the stabilities of the intermediate products with the primary and secondary amines in the aqueous solutions. The reaction rates with respect to the unreacted mass of PEN were represented by the surface reaction model, i.e., 2/3rd order reaction kinetics, as previously observed for poly(ethylene terephthalate) in aqueous solutions of ammonia and amine at low concentrations. The apparent rate constant from the surface reaction model was proportional to the amine concentration.

DOI： 10.1252/jcej.14we065

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The effects of temperature and density on retention of platinum(II) 2,4-pentanedionate in supercritical fluid chromatography were investigated at temperatures of 308.15-343.15 K and pressure range from 8 to 40 MPa by the chromatographic impulse response method with curve fitting. The retention factors were utilized to derive the infinite dilution partial molar volumes of platinum(II) 2,4-pentanedionate in supercritical carbon dioxide. The determined partial molar volumes were small and positive at high pressures but exhibited very large and negative values in the highly compressible near critical region of carbon dioxide. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2014.08.021

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The effects of temperature and density on retention of platinum(II) 2,4-pentanedionate in supercritical fluid chromatography were investigated at temperatures of 308.15-343.15 K and pressure range from 8 to 40 MPa by the chromatographic impulse response method with curve fitting. The retention factors were utilized to derive the infinite dilution partial molar volumes of platinum(II) 2,4-pentanedionate in supercritical carbon dioxide. The determined partial molar volumes were small and positive at high pressures but exhibited very large and negative values in the highly compressible near critical region of carbon dioxide. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2014.08.021

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記述言語：英語   出版者・発行元：SPRINGER  

Polycarbonate (PC) pellets were subjected to dilute aqueous ammonia solution under hydrothermal conditions in a semi-batch reactor at temperatures ranging from 433 to 463 K and at a pressure of 10 MPa. The PC pellets were almost completely converted to bisphenol A (BPA). During an initial certain period, referred to as an induction time, neither BPA nor total organic carbon in solution were detected, and the BPA yield increased with time. The monomer yield was well represented by a surface reaction model, two-thirds-order reaction with respect to the mass of unreacted PC. The overall rate constant of the reaction in 0.6 mol/kg aqueous ammonia solution at 433 K was about 15 times greater than that in 0.6 mol/kg NaOH solution. The rate constant at 433 K was proportional to the ammonia or NaOH concentration. There was a correlation between the induction time and temperature, as well as the ammonia or NaOH concentration. By carrying out the reaction in aqueous mixtures of (NH4)(2)SO4 and NaOH at various concentrations of NaOH, ammonia was confirmed not to function as an alkaline reagent, but as a nucleophile reagent.

DOI： 10.1007/s10163-013-0151-8

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記述言語：英語   出版者・発行元：SPRINGER  

Polycarbonate (PC) pellets were subjected to dilute aqueous ammonia solution under hydrothermal conditions in a semi-batch reactor at temperatures ranging from 433 to 463 K and at a pressure of 10 MPa. The PC pellets were almost completely converted to bisphenol A (BPA). During an initial certain period, referred to as an induction time, neither BPA nor total organic carbon in solution were detected, and the BPA yield increased with time. The monomer yield was well represented by a surface reaction model, two-thirds-order reaction with respect to the mass of unreacted PC. The overall rate constant of the reaction in 0.6 mol/kg aqueous ammonia solution at 433 K was about 15 times greater than that in 0.6 mol/kg NaOH solution. The rate constant at 433 K was proportional to the ammonia or NaOH concentration. There was a correlation between the induction time and temperature, as well as the ammonia or NaOH concentration. By carrying out the reaction in aqueous mixtures of (NH4)(2)SO4 and NaOH at various concentrations of NaOH, ammonia was confirmed not to function as an alkaline reagent, but as a nucleophile reagent.

DOI： 10.1007/s10163-013-0151-8

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

This study reports a one-pot synthesis technique for the preparation of single-phase monoclinic zirconium oxide (ZrO2) nanocrystals. The products were synthesized from only zirconium oxynitrate (ZrO(NO3)(2)) as the precursor under hydrothermal conditions using subcritical water. The precursor was heat-treated in a batch-type reactor at a reaction temperature of 250 degrees C for 24 h to obtain pure monoclinic-structured ZrO2 nanocrystals. The crystallization temperature of the ZrO2 phase was also greater than 200 degrees C. However, the products of reactions conducted at 200 degrees C for 24 h were mixtures of the tetragonal and monoclinic structures. At a reaction temperature of 250 degrees C, the volume fraction of the monoclinic phase increased; however, the reaction time was also important. The heat-treatment was performed for more than 12 h in order to obtain single-phase monoclinic ZrO2 nanocrystals. The crystallite size of this product was approximately 20 nm, and water, hydroxide groups, and nitro groups were chemisorbed on its surface. (C) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2013.11.001

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

This study reports a one-pot synthesis technique for the preparation of single-phase monoclinic zirconium oxide (ZrO2) nanocrystals. The products were synthesized from only zirconium oxynitrate (ZrO(NO3)(2)) as the precursor under hydrothermal conditions using subcritical water. The precursor was heat-treated in a batch-type reactor at a reaction temperature of 250 degrees C for 24 h to obtain pure monoclinic-structured ZrO2 nanocrystals. The crystallization temperature of the ZrO2 phase was also greater than 200 degrees C. However, the products of reactions conducted at 200 degrees C for 24 h were mixtures of the tetragonal and monoclinic structures. At a reaction temperature of 250 degrees C, the volume fraction of the monoclinic phase increased; however, the reaction time was also important. The heat-treatment was performed for more than 12 h in order to obtain single-phase monoclinic ZrO2 nanocrystals. The crystallite size of this product was approximately 20 nm, and water, hydroxide groups, and nitro groups were chemisorbed on its surface. (C) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2013.11.001

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

This study reports a one-pot synthesis technique for the preparation of single-phase monoclinic zirconium oxide (ZrO2) nanocrystals. The products were synthesized from only zirconium oxynitrate (ZrO(NO3)(2)) as the precursor under hydrothermal conditions using subcritical water. The precursor was heat-treated in a batch-type reactor at a reaction temperature of 250 degrees C for 24 h to obtain pure monoclinic-structured ZrO2 nanocrystals. The crystallization temperature of the ZrO2 phase was also greater than 200 degrees C. However, the products of reactions conducted at 200 degrees C for 24 h were mixtures of the tetragonal and monoclinic structures. At a reaction temperature of 250 degrees C, the volume fraction of the monoclinic phase increased; however, the reaction time was also important. The heat-treatment was performed for more than 12 h in order to obtain single-phase monoclinic ZrO2 nanocrystals. The crystallite size of this product was approximately 20 nm, and water, hydroxide groups, and nitro groups were chemisorbed on its surface. (C) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2013.11.001

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

This study reports a one-pot synthesis technique for the preparation of single-phase monoclinic zirconium oxide (ZrO2) nanocrystals. The products were synthesized from only zirconium oxynitrate (ZrO(NO3)(2)) as the precursor under hydrothermal conditions using subcritical water. The precursor was heat-treated in a batch-type reactor at a reaction temperature of 250 degrees C for 24 h to obtain pure monoclinic-structured ZrO2 nanocrystals. The crystallization temperature of the ZrO2 phase was also greater than 200 degrees C. However, the products of reactions conducted at 200 degrees C for 24 h were mixtures of the tetragonal and monoclinic structures. At a reaction temperature of 250 degrees C, the volume fraction of the monoclinic phase increased; however, the reaction time was also important. The heat-treatment was performed for more than 12 h in order to obtain single-phase monoclinic ZrO2 nanocrystals. The crystallite size of this product was approximately 20 nm, and water, hydroxide groups, and nitro groups were chemisorbed on its surface. (C) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2013.11.001

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記述言語：英語   出版者・発行元：ROYAL SOC CHEMISTRY  

This study reports a simple, rapid synthesis technique for the preparation of monocarboxylic acid-modified CeO2 nanoparticles. The nanoparticle products were prepared under hydrothermal conditions using supercritical water and Ce(OH)(4) as a precursor in the presence of monocarboxylic acids with different alkyl chain lengths (C6-18) acting as surface modifiers. The precursor and surface modifiers were heat-treated in a batch-type reactor at 400 degrees C for 30 min. The carboxylic acids attached to the surface of the products by coordination bonds between the carboxylate (-COO-) and Ce ions. The amount of attached surface modifiers tended to increase with increasing alkyl chain length. The products exhibited a cubic morphology and particle sizes of approximately 10 nm, controlled by the surface modifiers. Surface modification also controlled the band gap of the products, suggesting the possibility of tuning their electronic and optical properties by using organic surface modifiers.

DOI： 10.1039/c4ra06936f

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記述言語：英語   出版者・発行元：ROYAL SOC CHEMISTRY  

This study reports a simple, rapid synthesis technique for the preparation of monocarboxylic acid-modified CeO2 nanoparticles. The nanoparticle products were prepared under hydrothermal conditions using supercritical water and Ce(OH)(4) as a precursor in the presence of monocarboxylic acids with different alkyl chain lengths (C6-18) acting as surface modifiers. The precursor and surface modifiers were heat-treated in a batch-type reactor at 400 degrees C for 30 min. The carboxylic acids attached to the surface of the products by coordination bonds between the carboxylate (-COO-) and Ce ions. The amount of attached surface modifiers tended to increase with increasing alkyl chain length. The products exhibited a cubic morphology and particle sizes of approximately 10 nm, controlled by the surface modifiers. Surface modification also controlled the band gap of the products, suggesting the possibility of tuning their electronic and optical properties by using organic surface modifiers.

DOI： 10.1039/c4ra06936f

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

H-1 and Li-7 NMR chemical shifts of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide-water solutions in the presence and absence of lithium bis(trifluoromethanesulfonyl)amide were determined at 293.2 K over a wide range of water concentrations from 0.0156 to 1.16 mol kg(-1). These results revealed the attractive interaction between water molecule and Li+ as well as the hydrogen bonding among water molecules. Moreover, self-diffusion coefficients of water, 1-ethyl-3-methylimidazolium cation, Li+, and bis(trifluoromethanesulfonyl)amide anion in the ionic liquid solutions at various water contents were determined by H-1, Li-7, and F-19 NMR techniques. It was found that Li+ is averagely hydrated by eight water molecules in the ionic liquid solutions. Furthermore, Li-7 longitudinal relaxation times of Li+ in the ionic liquid solutions at 293.2 K were measured with two different magnetic fields and various water contents. The mean one-jump distances of Li+ in the ionic liquid solutions were estimated from the correlation times and the self-diffusion coefficients. A comparison between the hydrodynamic radius and the mean one-jump distance of Li+ suggested the formation of water channels in the ionic liquid solutions.

DOI： 10.1021/jp409324k

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

H-1 and Li-7 NMR chemical shifts of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide-water solutions in the presence and absence of lithium bis(trifluoromethanesulfonyl)amide were determined at 293.2 K over a wide range of water concentrations from 0.0156 to 1.16 mol kg(-1). These results revealed the attractive interaction between water molecule and Li+ as well as the hydrogen bonding among water molecules. Moreover, self-diffusion coefficients of water, 1-ethyl-3-methylimidazolium cation, Li+, and bis(trifluoromethanesulfonyl)amide anion in the ionic liquid solutions at various water contents were determined by H-1, Li-7, and F-19 NMR techniques. It was found that Li+ is averagely hydrated by eight water molecules in the ionic liquid solutions. Furthermore, Li-7 longitudinal relaxation times of Li+ in the ionic liquid solutions at 293.2 K were measured with two different magnetic fields and various water contents. The mean one-jump distances of Li+ in the ionic liquid solutions were estimated from the correlation times and the self-diffusion coefficients. A comparison between the hydrodynamic radius and the mean one-jump distance of Li+ suggested the formation of water channels in the ionic liquid solutions.

DOI： 10.1021/jp409324k

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Binary diffusion coefficients (D-12) and retention factors (k) of platinum(II) acetylacetonate at infinitesimal concentration in supercritical (sc) carbon dioxide (CO2) were measured by the chromatographic impulse response method with a poly(ethylene glycol) coated capillary column at temperatures from (308.15 to 343.15) K and pressures from (8.5 to 40.0) MPa, and D-12 in liquid ethanol at temperatures from (298.15 to 333.15) K and atmospheric pressure by the Taylor dispersion method. As has been seen for our previously reported data on other metal complexes measured in se CO2 and organic solvents, the D-12 data in sc CO2 and liquid ethanol were represented by a function of temperature and solvent viscosity. The D-12 values for metal complexes were not related to the solute molecular weights. The k values in sc CO2 were expressed by a function of temperature and CO2 density.

DOI： 10.1021/je400313n

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Binary diffusion coefficients (D-12) and retention factors (k) of platinum(II) acetylacetonate at infinitesimal concentration in supercritical (sc) carbon dioxide (CO2) were measured by the chromatographic impulse response method with a poly(ethylene glycol) coated capillary column at temperatures from (308.15 to 343.15) K and pressures from (8.5 to 40.0) MPa, and D-12 in liquid ethanol at temperatures from (298.15 to 333.15) K and atmospheric pressure by the Taylor dispersion method. As has been seen for our previously reported data on other metal complexes measured in se CO2 and organic solvents, the D-12 data in sc CO2 and liquid ethanol were represented by a function of temperature and solvent viscosity. The D-12 values for metal complexes were not related to the solute molecular weights. The k values in sc CO2 were expressed by a function of temperature and CO2 density.

DOI： 10.1021/je400313n

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Mutual diffusion coefficients for aqueous solutions of 3-aminopropanoic acid (beta-alanine), 4-aminobutanoic acid (gamma-aminobutyric acid), 5-aminopentanoic acid, 6-aminohexanoic acid, and 7-aminoheptanoic acid at infinitesimal concentration were measured at atmospheric pressure and temperatures from (298.2 to 333.2) K using the Taylor dispersion method. The results were compared with those of the structural isomers measured in our previous studies to examine the effect of position of amino and carboxylic acid groups on the values of diffusion coefficients. The diffusion coefficients of all amino acid isomers were almost the same, indicating that the diffusion coefficients of amino acids measured in our studies were mostly determined by the molar mass and the increase in the distance between amino and carboxylic acid groups was not an important factor. The temperature dependences of the diffusion coefficients were well-correlated with viscosity of water, eta, as D-12/T = alpha eta(beta) where D-12 is the diffusion coefficient at infinitesimal concentration of solute, T is the absolute temperature, and alpha and beta are the fitting parameters.

DOI： 10.1021/je301370s

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Mutual diffusion coefficients for aqueous solutions of 3-aminopropanoic acid (beta-alanine), 4-aminobutanoic acid (gamma-aminobutyric acid), 5-aminopentanoic acid, 6-aminohexanoic acid, and 7-aminoheptanoic acid at infinitesimal concentration were measured at atmospheric pressure and temperatures from (298.2 to 333.2) K using the Taylor dispersion method. The results were compared with those of the structural isomers measured in our previous studies to examine the effect of position of amino and carboxylic acid groups on the values of diffusion coefficients. The diffusion coefficients of all amino acid isomers were almost the same, indicating that the diffusion coefficients of amino acids measured in our studies were mostly determined by the molar mass and the increase in the distance between amino and carboxylic acid groups was not an important factor. The temperature dependences of the diffusion coefficients were well-correlated with viscosity of water, eta, as D-12/T = alpha eta(beta) where D-12 is the diffusion coefficient at infinitesimal concentration of solute, T is the absolute temperature, and alpha and beta are the fitting parameters.

DOI： 10.1021/je301370s

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記述言語：英語  

Mutual diffusion coefficients at infinitesimal concentration and atmospheric pressure were measured for binary aqueous solutions of four α-amino acids (2-amino-3-phenylpropanoic acid (phenylalanine), 2-amino-3-(4-hydroxyphenyl)-propanoic acid (p-tyrosine), 2-amino-3-(3- hydroxyphenyl)-propanoic acid (m-tyrosine), and 2-amino-3-(2-hydroxyphenyl)- propanoic acid (o-tyrosine)) at temperatures from (298.3 to 313.2) K and five aminobutyric acid isomers (2-aminobutanoic acid (α-aminobutyric acid), 2-amino-2-methylpropanoic acid (α-aminoisobutyric acid), 3-aminobutanoic acid (β-aminobutyric acid), 3-amino-2-methylpropanoic acid (β-aminoisobutyric acid), and 4-aminobutanoic acid (γ-aminobutyric acid)) at temperatures from (293.2 to 333.2) K. The diffusion coefficients for each of the amino acids were well-represented by a simple correlation as a function of temperature and solvent viscosity with two adjustable parameters determined for each solute. The two parameters determined for each amino acid in our present and previous studies were closely related to the molar volume of the amino acids at its normal boiling point. We proposed predictive correlations for the diffusion coefficients of aqueous amino acid solutions at infinitesimal concentrations and tested the accuracy of the predictions with the reference data for aqueous amino acids at 298.2 K. © 2013 American Chemical Society.

DOI： 10.1021/je3012698

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記述言語：英語  

Mutual diffusion coefficients at infinitesimal concentration and atmospheric pressure were measured for binary aqueous solutions of four α-amino acids (2-amino-3-phenylpropanoic acid (phenylalanine), 2-amino-3-(4-hydroxyphenyl)-propanoic acid (p-tyrosine), 2-amino-3-(3- hydroxyphenyl)-propanoic acid (m-tyrosine), and 2-amino-3-(2-hydroxyphenyl)- propanoic acid (o-tyrosine)) at temperatures from (298.3 to 313.2) K and five aminobutyric acid isomers (2-aminobutanoic acid (α-aminobutyric acid), 2-amino-2-methylpropanoic acid (α-aminoisobutyric acid), 3-aminobutanoic acid (β-aminobutyric acid), 3-amino-2-methylpropanoic acid (β-aminoisobutyric acid), and 4-aminobutanoic acid (γ-aminobutyric acid)) at temperatures from (293.2 to 333.2) K. The diffusion coefficients for each of the amino acids were well-represented by a simple correlation as a function of temperature and solvent viscosity with two adjustable parameters determined for each solute. The two parameters determined for each amino acid in our present and previous studies were closely related to the molar volume of the amino acids at its normal boiling point. We proposed predictive correlations for the diffusion coefficients of aqueous amino acid solutions at infinitesimal concentrations and tested the accuracy of the predictions with the reference data for aqueous amino acids at 298.2 K. © 2013 American Chemical Society.

DOI： 10.1021/je3012698

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The diffusion coefficients D-12 of phenylbutazone at infinite dilution in supercritical CO2 were measured by the chromatographic impulse response (CIR) method. The measurements were carried out over the temperature range from 308.2 to 343.2 K at pressures up to 40.0 MPa. In addition, the D-12 data of phenylbutazone at infinite dilution in ethanol were also measured by the Taylor dispersion method at 298.2-333.2 K and at atmospheric pressure. The D-12 value of phenylbutazone increased from 4.45 x 10(-10) m(2) s(-1) 298.2 K and 0.1 MPa in ethanol to about 1.43 x 10(-8) m(2) s(-1) at 343.2 K and 14.0 MPa in supercritical CO2. It was found that all diffusion data of phenylbutazone measured in this study in supercritical CO2 and in ethanol can be satisfactorily represented by the hydrodynamic equation over a wide range of fluid viscosity from supercritical state to liquid state with average absolute relative deviation of 5.4% for 112 data points. (C) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2013.01.019

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The diffusion coefficients D-12 of phenylbutazone at infinite dilution in supercritical CO2 were measured by the chromatographic impulse response (CIR) method. The measurements were carried out over the temperature range from 308.2 to 343.2 K at pressures up to 40.0 MPa. In addition, the D-12 data of phenylbutazone at infinite dilution in ethanol were also measured by the Taylor dispersion method at 298.2-333.2 K and at atmospheric pressure. The D-12 value of phenylbutazone increased from 4.45 x 10(-10) m(2) s(-1) 298.2 K and 0.1 MPa in ethanol to about 1.43 x 10(-8) m(2) s(-1) at 343.2 K and 14.0 MPa in supercritical CO2. It was found that all diffusion data of phenylbutazone measured in this study in supercritical CO2 and in ethanol can be satisfactorily represented by the hydrodynamic equation over a wide range of fluid viscosity from supercritical state to liquid state with average absolute relative deviation of 5.4% for 112 data points. (C) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2013.01.019

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記述言語：英語  

Infinite dilution binary diffusion coefficients (D12) for compounds derived from biomass such as furan-2-carbaldehyde (furfural), 5-(hydroxymethyl)-2-furaldehyde (5-HMF), 2-methoxyphenol (guaiacol), 4-hydroxy-3-methoxybenzaldehyde (vanillin), and phenol in water were measured over the temperature range from (298.2 to 353.2) K at 0.1 MPa using the Taylor dispersion method. The relative expanded uncertainties with level of confidence 0.95 (the coverage factor, k = 2.78 for 4 degrees of freedom) for the measured diffusion coefficients were less than 5.8 % and typically ca. 2.4 %. The diffusion coefficients were correlated with the hydrodynamic equation, D 12/T = αηβ, with an average absolute relative deviation, AARD, less than 1.16 %. © 2012 American Chemical Society.

DOI： 10.1021/je301060a

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Infinite dilution binary diffusion coefficients (D-12) for compounds derived from biomass such as furan-2-carbaldehyde (furfural), 5-(hydroxymethyl)-2-furaldehyde (5-HMF), 2-methoxyphenol (guaiacol), 4-hydroxy-3-methoxybenzaldehyde (vanillin), and phenol in water were measured over the temperature range from (298.2 to 353.2) K at 0.1 MPa using the Taylor dispersion method. The relative expanded uncertainties with level of confidence 0.95 (the coverage factor, k = 2.78 for 4 degrees of freedom) for the measured diffusion coefficients were less than 5.8 % and typically ca. 2.4 %. The diffusion coefficients were correlated with the hydrodynamic equation, D-12/T = alpha eta(beta), with an average absolute relative deviation, AARD, less than 1.16 %.

DOI： 10.1021/je301060a

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Infinite dilution binary diffusion coefficients (D-12) for compounds derived from biomass such as furan-2-carbaldehyde (furfural), 5-(hydroxymethyl)-2-furaldehyde (5-HMF), 2-methoxyphenol (guaiacol), 4-hydroxy-3-methoxybenzaldehyde (vanillin), and phenol in water were measured over the temperature range from (298.2 to 353.2) K at 0.1 MPa using the Taylor dispersion method. The relative expanded uncertainties with level of confidence 0.95 (the coverage factor, k = 2.78 for 4 degrees of freedom) for the measured diffusion coefficients were less than 5.8 % and typically ca. 2.4 %. The diffusion coefficients were correlated with the hydrodynamic equation, D-12/T = alpha eta(beta), with an average absolute relative deviation, AARD, less than 1.16 %.

DOI： 10.1021/je301060a

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Infinite dilution binary diffusion coefficients (D-12) for compounds derived from biomass such as furan-2-carbaldehyde (furfural), 5-(hydroxymethyl)-2-furaldehyde (5-HMF), 2-methoxyphenol (guaiacol), 4-hydroxy-3-methoxybenzaldehyde (vanillin), and phenol in water were measured over the temperature range from (298.2 to 353.2) K at 0.1 MPa using the Taylor dispersion method. The relative expanded uncertainties with level of confidence 0.95 (the coverage factor, k = 2.78 for 4 degrees of freedom) for the measured diffusion coefficients were less than 5.8 % and typically ca. 2.4 %. The diffusion coefficients were correlated with the hydrodynamic equation, D-12/T = alpha eta(beta), with an average absolute relative deviation, AARD, less than 1.16 %.

DOI： 10.1021/je301060a

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記述言語：英語   出版者・発行元：ROYAL SOC CHEMISTRY  

In this study, we report a rapid and simple technique for obtaining cobalt aluminate having a spinel structure. The products were prepared from a hydroxide precursor synthesized by coprecipitation of cobalt (Co2+) and aluminum (Al3+) nitrates with an alkaline solution. The chosen precursor enabled low temperature fabrication of cobalt aluminate with a spinel structure by sintering it for 2 hours at low temperatures (>400 degrees C). Crystallographic and thermal analyses suggest that the low-temperature-sintered products contain Co3+ ions stabilized by chemisorbed water and/or hydroxide groups, which was not observed for products sintered at temperatures higher than 1000 degrees C. The color of the products turned from clear blue (Thenard's blue) to dark green when sintering temperatures were below 1000 degrees C. Magnetic quantities, Curie constants, and Weiss temperatures show a strong dependence on the sintering temperature. These findings suggest that there are mixed valent states, i.e. Co2+ and Co3+, and unique cation distributions at the different crystallographic sites in the spinel structure, especially in the products sintered at lower temperatures.

DOI： 10.1039/c3dt32828g

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記述言語：英語   出版者・発行元：ROYAL SOC CHEMISTRY  

In this study, we report a rapid and simple technique for obtaining cobalt aluminate having a spinel structure. The products were prepared from a hydroxide precursor synthesized by coprecipitation of cobalt (Co2+) and aluminum (Al3+) nitrates with an alkaline solution. The chosen precursor enabled low temperature fabrication of cobalt aluminate with a spinel structure by sintering it for 2 hours at low temperatures (>400 degrees C). Crystallographic and thermal analyses suggest that the low-temperature-sintered products contain Co3+ ions stabilized by chemisorbed water and/or hydroxide groups, which was not observed for products sintered at temperatures higher than 1000 degrees C. The color of the products turned from clear blue (Thenard's blue) to dark green when sintering temperatures were below 1000 degrees C. Magnetic quantities, Curie constants, and Weiss temperatures show a strong dependence on the sintering temperature. These findings suggest that there are mixed valent states, i.e. Co2+ and Co3+, and unique cation distributions at the different crystallographic sites in the spinel structure, especially in the products sintered at lower temperatures.

DOI： 10.1039/c3dt32828g

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記述言語：英語   掲載種別：書評論文，書評，文献紹介等   出版者・発行元：ELSEVIER SCIENCE BV  

The use of chromatographic impulse response (CIR) method with a coated open tubular capillary column has potential advantages in supercritical fluid chromatography. In this review, applications of the CIR method to measuring the thermodynamic properties such as diffusion coefficients, solubilities and partial molar volumes are presented. This survey gives the theoretical backgrounds for the CIR method with linear adsorption and nonlinear adsorption models. Furthermore, the brief theoretical backgrounds for using retention factors to determine solubilities and partial molar volumes are also provided. In addition, the data sources for the diffusion coefficients with an emphasis on the results published after 2004 and for the partial molar volumes in supercritical carbon dioxide are presented. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2012.04.033

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記述言語：英語   掲載種別：書評論文，書評，文献紹介等   出版者・発行元：ELSEVIER SCIENCE BV  

The use of chromatographic impulse response (CIR) method with a coated open tubular capillary column has potential advantages in supercritical fluid chromatography. In this review, applications of the CIR method to measuring the thermodynamic properties such as diffusion coefficients, solubilities and partial molar volumes are presented. This survey gives the theoretical backgrounds for the CIR method with linear adsorption and nonlinear adsorption models. Furthermore, the brief theoretical backgrounds for using retention factors to determine solubilities and partial molar volumes are also provided. In addition, the data sources for the diffusion coefficients with an emphasis on the results published after 2004 and for the partial molar volumes in supercritical carbon dioxide are presented. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2012.04.033

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Poly(ethylene terephthalate) pellets were subjected to various amine solutions under hydrothermal conditions in a semibatch reactor. Methylamine, ethylamine, dirnethylamine, trimethylamine, ammonia, and sodium hydroxide were examined at 473 K and 10 MPa at concentrations of 0.6 mol/kg. The effects of the amine species on reaction rates and monomer yields were compared. For all solvents examined in the present study, the reactions were expressed by a surface reaction model, i.e., the 2/3rd-order reaction kinetics with respect to unreacted polymer mass. The reaction rates with the four amines were not very different and were similar to that with NaOH at the same concentration; but, they were faster than the rate with ammonia. When the reaction was conducted with trimethylamine, the yields of monomers and total yields of terephthalic acid and ethylene glycol were very close to the theoretical values. However, those with dimethylamine, ethylamine, and methylamine were slightly lower with intermediate products found in the product solutions.

DOI： 10.1021/ie202885u

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Poly(ethylene terephthalate) pellets were subjected to various amine solutions under hydrothermal conditions in a semibatch reactor. Methylamine, ethylamine, dirnethylamine, trimethylamine, ammonia, and sodium hydroxide were examined at 473 K and 10 MPa at concentrations of 0.6 mol/kg. The effects of the amine species on reaction rates and monomer yields were compared. For all solvents examined in the present study, the reactions were expressed by a surface reaction model, i.e., the 2/3rd-order reaction kinetics with respect to unreacted polymer mass. The reaction rates with the four amines were not very different and were similar to that with NaOH at the same concentration; but, they were faster than the rate with ammonia. When the reaction was conducted with trimethylamine, the yields of monomers and total yields of terephthalic acid and ethylene glycol were very close to the theoretical values. However, those with dimethylamine, ethylamine, and methylamine were slightly lower with intermediate products found in the product solutions.

DOI： 10.1021/ie202885u

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記述言語：英語   出版者・発行元：SPRINGER  

Cotton cellulose subjected to a dilute aqueous formic acid solution, at acid concentrations up to 1% (w/w), under hydrothermal conditions in a semi-batch reactor was converted into glucose and oligomers with lower degrees of polymerizations (DP). After heating at 250 degrees C for 60 min in 0.1% (w/w) aqueous formic acid solution, yields of glucose and total sugar with DP = 1 to 9 were 36.6 and 83.8% (100 x gC/gC of initial cotton sample), respectively, and 5-hydroxymethylfurfural was almost as low as 1%. The yields of glucose and oligomers were significantly improved by adding the acid. The reaction was represented by first-order reaction kinetics with regard to (1 - x) where x is the conversion based on the total sugar or glucose yield. At 250 degrees C, the differences in the rate constants (k - k(water)) were proportional to the square root of formic acid concentration.

DOI： 10.1007/s11164-011-0246-6

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記述言語：英語   出版者・発行元：SPRINGER  

Cotton cellulose subjected to a dilute aqueous formic acid solution, at acid concentrations up to 1% (w/w), under hydrothermal conditions in a semi-batch reactor was converted into glucose and oligomers with lower degrees of polymerizations (DP). After heating at 250 degrees C for 60 min in 0.1% (w/w) aqueous formic acid solution, yields of glucose and total sugar with DP = 1 to 9 were 36.6 and 83.8% (100 x gC/gC of initial cotton sample), respectively, and 5-hydroxymethylfurfural was almost as low as 1%. The yields of glucose and oligomers were significantly improved by adding the acid. The reaction was represented by first-order reaction kinetics with regard to (1 - x) where x is the conversion based on the total sugar or glucose yield. At 250 degrees C, the differences in the rate constants (k - k(water)) were proportional to the square root of formic acid concentration.

DOI： 10.1007/s11164-011-0246-6

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The solubilities of organometallic complexes in supercritical CO(2) were determined from retention factors measured by the chromatographic impulse response (CIR) method, in which a solute was pulse-injected into a supercritical CO(2) flowing in a polymer coated open capillary column, and the response curve, i.e. time change of solute concentration, was monitored at the exit of the column. The retention factor and binary diffusion coefficient were simultaneously obtained as two parameters so that the fitting error between response curves of solute species measured and calculated was minimized. The validities of the method and the apparatus employed in this study were verified by determining the solubilities of naphthalene, which have extensively been reported in the literature. Then, the solubilities of organometallic complexes such as ferrocene and cobalt (III) acetylacetonate in supercritical CO(2) were determined. The data determined in this study were in good agreement with the literature data. The solubilities were also correlated with the Chrastil equation including the three adjustable parameters. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2010.09.034

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The solubilities of organometallic complexes in supercritical CO(2) were determined from retention factors measured by the chromatographic impulse response (CIR) method, in which a solute was pulse-injected into a supercritical CO(2) flowing in a polymer coated open capillary column, and the response curve, i.e. time change of solute concentration, was monitored at the exit of the column. The retention factor and binary diffusion coefficient were simultaneously obtained as two parameters so that the fitting error between response curves of solute species measured and calculated was minimized. The validities of the method and the apparatus employed in this study were verified by determining the solubilities of naphthalene, which have extensively been reported in the literature. Then, the solubilities of organometallic complexes such as ferrocene and cobalt (III) acetylacetonate in supercritical CO(2) were determined. The data determined in this study were in good agreement with the literature data. The solubilities were also correlated with the Chrastil equation including the three adjustable parameters. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2010.09.034

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Infinite dilution binary diffusion coefficients, D(12), of ferrocene, 1,1'-dimethylferrocene and ethylferrocene in hexane, cyclohexane and ethanol at 313.2 K and pressures from 0.2 to 19 MPa, in acetonitrile at 298.2-333.2 K and 0.2 MPa, and various metallic acetylacetonate, acac, complexes such as Co(acac)(3), Ru(acac)(3), Rh(acac)(3), Pd(acac)(2) and Pt(acac)(2) mainly in ethanol at 313.2 K and 0.2 MPa were measured by the Taylor dispersion method. The D(12) values in m(2)s(-1) for the three ferrocenes in the present study and those of ferrocene and 1,1'-dimethylferrocene in supercritical carbon dioxide in our previous studies were represented by the modified hydrodynamic equation over a wide range of viscosity: M(0.5)D(12)/T = 1.435 x 10(-13)eta(-0.8446) with average absolute relative deviation of 2.40% for 316 data points, where M is the solute molecular weight. T is the temperature in K. eta is the solvent viscosity in Pa s. Although the D(12) values for the acac complexes were roughly represented by the above hydrodynamic equation, the accuracies were lower because they were dependent on not solute molecular weight but the number of acac ligand in the complex molecules. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2010.06.003

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Molecular dynamics (MD) simulations for aqueous NaCl solution were performed from ambient to supercritical conditions (25 degrees C, 1.0 g cm(-3): 250-350 degrees C, 0.67-0.8 g cm(-3); 380 degrees C, 0.2-0.8 g cm(-3): and 400-600 degrees C, 0.4 and 0.7 g cm(-3)) in the canonical ensemble to examine how the hydration structure relates with the thermodynamics of the ion-pair association. Hydration structure and the potential of mean force (PMF) of Na(+)Cl(-) ion-pair were calculated. ion-pair association constants were also calculated from the PMFs. Energies and entropies of the ion-pair at arbitrary inter-ionic distances from 2.0 to 8.0 angstrom were evaluated from the temperature derivative of the PMFs. From the calculation of energies and entropies, Na(+)-Cl(-) pair association was found to be endothermic and promoted by the entropy gain. PMFs had minimums and a slight maximum corresponding to CIP, SShIP, and the transition state between CIP and SShIP, and similar minimums and maximum were only observed for the energy term and not clearly observed for the entropy term. This result indicates that the shape of the PMF and stability of SShIP are determined by the energy of the system. Relationship between the hydration structure and the energy of the system was examined and it was confirmed that the hydration structure in the first hydration shell of the ion-pair was one of the important factor, which made the minimums and maximum in the energy terms and PMFs, and stabilized the SShIP structure. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2010.05.012

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Molecular dynamics (MD) simulations for aqueous NaCl solution were performed from ambient to supercritical conditions (25 degrees C, 1.0 g cm(-3): 250-350 degrees C, 0.67-0.8 g cm(-3); 380 degrees C, 0.2-0.8 g cm(-3): and 400-600 degrees C, 0.4 and 0.7 g cm(-3)) in the canonical ensemble to examine how the hydration structure relates with the thermodynamics of the ion-pair association. Hydration structure and the potential of mean force (PMF) of Na(+)Cl(-) ion-pair were calculated. ion-pair association constants were also calculated from the PMFs. Energies and entropies of the ion-pair at arbitrary inter-ionic distances from 2.0 to 8.0 angstrom were evaluated from the temperature derivative of the PMFs. From the calculation of energies and entropies, Na(+)-Cl(-) pair association was found to be endothermic and promoted by the entropy gain. PMFs had minimums and a slight maximum corresponding to CIP, SShIP, and the transition state between CIP and SShIP, and similar minimums and maximum were only observed for the energy term and not clearly observed for the entropy term. This result indicates that the shape of the PMF and stability of SShIP are determined by the energy of the system. Relationship between the hydration structure and the energy of the system was examined and it was confirmed that the hydration structure in the first hydration shell of the ion-pair was one of the important factor, which made the minimums and maximum in the energy terms and PMFs, and stabilized the SShIP structure. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2010.05.012

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Binary diffusion coefficients, D(12), of the metal acetylacetonates, palladium(II) acetylacetonate and cobalt(III)acetylacetonate, were measured from 308.2 to 343.2 K over the pressure range from 9 to 40 MPa at infinite dilution in supercritical carbon dioxide using the chromatographic impulse response method. The effects of pressure, temperature, density, and viscosity on D(12) values were examined. It was observed that the D(12) values of palladium(II)acetylacetonate and cobalt(III)acetylacetonate were larger than those of lipids with similar molecular weights, such as arachidonic acid and monoolein, respectively. Furthermore, the measured D(12) data of each metal acetylacetonate were well correlated by the hydrodynamic equation D(12)/T as a function of carbon dioxide viscosity. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2010.02.036

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Binary diffusion coefficients, D(12), of the metal acetylacetonates, palladium(II) acetylacetonate and cobalt(III)acetylacetonate, were measured from 308.2 to 343.2 K over the pressure range from 9 to 40 MPa at infinite dilution in supercritical carbon dioxide using the chromatographic impulse response method. The effects of pressure, temperature, density, and viscosity on D(12) values were examined. It was observed that the D(12) values of palladium(II)acetylacetonate and cobalt(III)acetylacetonate were larger than those of lipids with similar molecular weights, such as arachidonic acid and monoolein, respectively. Furthermore, the measured D(12) data of each metal acetylacetonate were well correlated by the hydrodynamic equation D(12)/T as a function of carbon dioxide viscosity. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2010.02.036

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Infinite dilution binary diffusion coefficients, D(12), of ferrocene, 1,1'-dimethylferrocene and ethylferrocene in hexane, cyclohexane and ethanol at 313.2 K and pressures from 0.2 to 19 MPa, in acetonitrile at 298.2-333.2 K and 0.2 MPa, and various metallic acetylacetonate, acac, complexes such as Co(acac)(3), Ru(acac)(3), Rh(acac)(3), Pd(acac)(2) and Pt(acac)(2) mainly in ethanol at 313.2 K and 0.2 MPa were measured by the Taylor dispersion method. The D(12) values in m(2)s(-1) for the three ferrocenes in the present study and those of ferrocene and 1,1'-dimethylferrocene in supercritical carbon dioxide in our previous studies were represented by the modified hydrodynamic equation over a wide range of viscosity: M(0.5)D(12)/T = 1.435 x 10(-13)eta(-0.8446) with average absolute relative deviation of 2.40% for 316 data points, where M is the solute molecular weight. T is the temperature in K. eta is the solvent viscosity in Pa s. Although the D(12) values for the acac complexes were roughly represented by the above hydrodynamic equation, the accuracies were lower because they were dependent on not solute molecular weight but the number of acac ligand in the complex molecules. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2010.06.003

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Binary diffusion coefficients D(12) and retention factors k of ferrocene and 1,1'-dimethylferrocene at infinite dilution in supercritical (sc) carbon dioxide were measured by the chromatographic impulse response (CIR) method at temperatures from (308.2 to 323.2) K over a pressure range from (8.0 to 40.3) MPa for ferrocene and from (8.2 to 40.1) MPa for 1, 1'-dimethylferrocene. The D(12) data for ferrocene were also measured by the Taylor dispersion method with two injection procedures of ferrocene: ferrocene dissolved both in sc CO(2) and in liquid hexane. The D(12) values of ferrocene were not affected by the injection methods and agreed with those measured by the CIR method. As has been seen for various organic compounds measured in our previous reports, the D(12) data for both metal complexes were correlated with the hydrodynamic equation D(12)/T = alpha eta(beta), where eta is the CO(2) viscosity and alpha and beta are the constants determined by each solute. The retention factors were also correlated with CO(2) density.

DOI： 10.1021/je901096d

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Binary diffusion coefficients D(12) and retention factors k of ferrocene and 1,1'-dimethylferrocene at infinite dilution in supercritical (sc) carbon dioxide were measured by the chromatographic impulse response (CIR) method at temperatures from (308.2 to 323.2) K over a pressure range from (8.0 to 40.3) MPa for ferrocene and from (8.2 to 40.1) MPa for 1, 1'-dimethylferrocene. The D(12) data for ferrocene were also measured by the Taylor dispersion method with two injection procedures of ferrocene: ferrocene dissolved both in sc CO(2) and in liquid hexane. The D(12) values of ferrocene were not affected by the injection methods and agreed with those measured by the CIR method. As has been seen for various organic compounds measured in our previous reports, the D(12) data for both metal complexes were correlated with the hydrodynamic equation D(12)/T = alpha eta(beta), where eta is the CO(2) viscosity and alpha and beta are the constants determined by each solute. The retention factors were also correlated with CO(2) density.

DOI： 10.1021/je901096d

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Poly(L-lactic acid) (PLLA) pellets were degraded in a batch reactor under hydrothermal conditions of aqueous sodium hydroxide Solution, from 343 to 453 K, compared to water in the absence of NaOH. Over ail entire range of conversion, Components solubilized from PLLA mainly consisted Or L-lactic acid (LLA) in the presence of NaOH. For instance, PLLA was nearly completely converted into LLA at 433 K for 60 min or 453 K for 20 min with 0.6 M aqueous NaOH solution, where D-lactic acid was not observed. The degradation reaction with/without NaOH proceeded in the induction stage followed by the major degradation stage, as has been seen for polyesters reported in our previous Studies. In the major degradation stage the overall reaction rate for PLLA was represented by 2/3-order reaction kinetics with respect to the amount of unreacted polymer, suggesting that the reaction occurred on the polymer Surface. The NaOH concentrations above 0.6 M at 343 K hardly affected the reaction rates, but did affect the induction time remarkably. It can be considered that the degradation reaction is controlled by not chemical reaction but dissolution of products on the pellet surface.

DOI： 10.1021/ie9008925

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Poly(L-lactic acid) (PLLA) pellets were degraded in a batch reactor under hydrothermal conditions of aqueous sodium hydroxide Solution, from 343 to 453 K, compared to water in the absence of NaOH. Over ail entire range of conversion, Components solubilized from PLLA mainly consisted Or L-lactic acid (LLA) in the presence of NaOH. For instance, PLLA was nearly completely converted into LLA at 433 K for 60 min or 453 K for 20 min with 0.6 M aqueous NaOH solution, where D-lactic acid was not observed. The degradation reaction with/without NaOH proceeded in the induction stage followed by the major degradation stage, as has been seen for polyesters reported in our previous Studies. In the major degradation stage the overall reaction rate for PLLA was represented by 2/3-order reaction kinetics with respect to the amount of unreacted polymer, suggesting that the reaction occurred on the polymer Surface. The NaOH concentrations above 0.6 M at 343 K hardly affected the reaction rates, but did affect the induction time remarkably. It can be considered that the degradation reaction is controlled by not chemical reaction but dissolution of products on the pellet surface.

DOI： 10.1021/ie9008925

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記述言語：英語   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

Poly(ethylene naphthalate) (PEN), poly(ethylene terephthalate) (PET) and poly(carbonate) (PC) were depolymerized in a semi-batch reactor with a 0.6 M aqueous ammonia solution under hydrothermal conditions, at 433-553 K and 10 MPa, compared with aqueous alkaline (NaOH and KOH) solutions and water alone. The polymers studied were almost completely converted into monomers in an aqueous ammonia solution as well as aqueous NaOH and KOH solutions under hydrothermal conditions. The depolymerization reactions for the three polymers consisted of the initial induction stage, where the reactions proceeded very slowly, and the major depolymerization stage thereafter. The induction times were correlated with temperature. In the latter stage the overall depolymerization rate for each polymer was represented by 2/3-order reaction kinetics with respect to the amount of unreacted polymer, suggesting that the reaction occurred on the polymer surface. The depolymerization rates for PC with a 0.6 M aqueous ammonia solution were much faster than those with a 0.6 M aqueous NaOH solution. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ces.2009.03.023

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記述言語：英語   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

Poly(ethylene naphthalate) (PEN), poly(ethylene terephthalate) (PET) and poly(carbonate) (PC) were depolymerized in a semi-batch reactor with a 0.6 M aqueous ammonia solution under hydrothermal conditions, at 433-553 K and 10 MPa, compared with aqueous alkaline (NaOH and KOH) solutions and water alone. The polymers studied were almost completely converted into monomers in an aqueous ammonia solution as well as aqueous NaOH and KOH solutions under hydrothermal conditions. The depolymerization reactions for the three polymers consisted of the initial induction stage, where the reactions proceeded very slowly, and the major depolymerization stage thereafter. The induction times were correlated with temperature. In the latter stage the overall depolymerization rate for each polymer was represented by 2/3-order reaction kinetics with respect to the amount of unreacted polymer, suggesting that the reaction occurred on the polymer surface. The depolymerization rates for PC with a 0.6 M aqueous ammonia solution were much faster than those with a 0.6 M aqueous NaOH solution. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ces.2009.03.023

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記述言語：英語   出版者・発行元：SOC CHEMICAL ENG JAPAN  

Corn grains are pulverized by steam explosion after 40 min cooking at 533 K, and the products are further hydrolyzed under hydrothermal conditions. Residual solids consisting of particles having average diameter of 89 mu m are obtained by steam explosion, and about 50-60 wt%(C/C) on carbon weight basis of initial sample is converted into water soluble (WS) components. The steam exploded products are further hydrothermally degraded in a small batch reactor at 453 to 493 K. The yields of WS components are almost unchanged with time at 453 and 473 K, but the molecular weights significantly decrease to lower than 1000.

DOI： 10.1252/jcej.09we145

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記述言語：英語   出版者・発行元：SOC CHEMICAL ENG JAPAN  

Corn grains are pulverized by steam explosion after 40 min cooking at 533 K, and the products are further hydrolyzed under hydrothermal conditions. Residual solids consisting of particles having average diameter of 89 mu m are obtained by steam explosion, and about 50-60 wt%(C/C) on carbon weight basis of initial sample is converted into water soluble (WS) components. The steam exploded products are further hydrothermally degraded in a small batch reactor at 453 to 493 K. The yields of WS components are almost unchanged with time at 453 and 473 K, but the molecular weights significantly decrease to lower than 1000.

DOI： 10.1252/jcej.09we145

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記述言語：日本語   出版者・発行元：日本分光  

CiNii Books

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記述言語：英語  

The hydrodynamic equation D/T = αηβ, where D is the infinite dilution binary diffusion or self-diffusion coefficient, T is the temperature, η is the fluid viscosity, and α and β are constants, were demonstrated to be effective for predicting both binary diffusion and self-diffusion coefficients in high density fluids, i.e. liquid and supercritical states. When a solute was specified, the correlation well represented both binary diffusion and self-diffusion coefficients, irrespective of solvent over a wide solvent viscosity range. The solute-dependent constants α and β were determined for 12 solutes with average absolute deviation of 6.2% for 1006 data points. © 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2008.03.004

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記述言語：英語   出版者・発行元：JOHN WILEY & SONS LTD  

BACKGROUND: Various methods, such as glycolysis, methanolysis, and hydrolysis with supercritical water, have been investigated for chemical recycling of poly(ethylene terephthalate) (PET), which is used in large quantities for beverage containers. However, a more effective process is needed. RESULTS: PET was depolymerized in aqueous ammonia in a batch reactor and a semi-batch reactor over a temperature range 463 to 5 73 K, at a pressure 10 MPa, and with up to 3 mol L-1 ammonia. Total organic carbon in the product solution and yields of the major products such as terephthalic acid (TPA) and ethylene glycol (EG) were measured. The PET pellet sample was thoroughly solubilized in aqueous ammonia under hydrothermal conditions, and more than 90% of the initial PET samples were recovered as TPA+EG on a carbon weight basis. Depolymerization rates were represented by 2/3-order reaction kinetics with respect to unreacted PET, where the reaction took place on the PET pellet surface. The rate increased slightly with increasing ammonia concentration. CONCLUSION: Ammonia was effective for depolymerization of PET, allowing the recovery of TPA and EG under hydrothermal conditions. (c) 2008 Society of Chemical Industry.

DOI： 10.1002/jctb.1951

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記述言語：英語   出版者・発行元：JOHN WILEY & SONS LTD  

BACKGROUND: Various methods, such as glycolysis, methanolysis, and hydrolysis with supercritical water, have been investigated for chemical recycling of poly(ethylene terephthalate) (PET), which is used in large quantities for beverage containers. However, a more effective process is needed. RESULTS: PET was depolymerized in aqueous ammonia in a batch reactor and a semi-batch reactor over a temperature range 463 to 5 73 K, at a pressure 10 MPa, and with up to 3 mol L-1 ammonia. Total organic carbon in the product solution and yields of the major products such as terephthalic acid (TPA) and ethylene glycol (EG) were measured. The PET pellet sample was thoroughly solubilized in aqueous ammonia under hydrothermal conditions, and more than 90% of the initial PET samples were recovered as TPA+EG on a carbon weight basis. Depolymerization rates were represented by 2/3-order reaction kinetics with respect to unreacted PET, where the reaction took place on the PET pellet surface. The rate increased slightly with increasing ammonia concentration. CONCLUSION: Ammonia was effective for depolymerization of PET, allowing the recovery of TPA and EG under hydrothermal conditions. (c) 2008 Society of Chemical Industry.

DOI： 10.1002/jctb.1951

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The hydrodynamic equation D/T=alpha eta(beta), where D is the infinite dilution binary diffusion or self-diffusion coefficient, T is the temperature, eta is the fluid viscosity, and alpha and beta are constants, were demonstrated to be effective for predicting both binary diffusion and self-diffusion coefficients in high density fluids, i.e. liquid and supercritical states. When a solute was specified, the correlation well represented both binary diffusion and self-diffusion coefficients, irrespective of solvent over a wide solvent viscosity range. The solute-dependent constants alpha and beta were determined for 12 solutes with average absolute deviation of 6.2% for 1006 data points. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2008.03.004

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記述言語：英語   出版者・発行元：SPRINGER  

The naturally occurring polysaccharides, starch and pectic acid, were hydrothermally degraded in a semi-batch reactor coupled with a plug-flow reactor (PFR) to produce valuable chemicals including mono- and oligosaccharides over a temperature range from 160 to 240 degrees C at 10 MPa. The solid polysaccharide samples were solubilized in a semi-batch reactor, and the water-soluble (WS) components instantly entered the PFR in which further degradation took place. The reaction temperature and/or residence time in the PFR significantly affected the yields of oligosaccharides, monosaccharides and secondary decomposition products, and also the average molecular weight of WS components. The product distributions were expressed with severity, which combines the effects of temperature and time on the progress of the reaction, as a single reaction parameter. Using this parameter, it was found that similar product distributions were obtained at equal levels of severity. The severity parameter enabled easy interpretation of the change in product distribution for these reactions.

DOI： 10.1007/s10853-007-2014-y

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記述言語：英語   出版者・発行元：SPRINGER  

Urea was decomposed in sub- and supercritical water in the presence and the absence of hydrogen peroxide at temperatures from 538 to 651 K, 23 MPa and residence times up to 1.5 s in a continuous flow reactor. The initial concentrations of urea varied from 0.005 to 0.5 mol L(-1). The major products were carbon dioxide, and ammonia. As a minor product cyanic acid was detected without hydrogen peroxide, and nitric acid and nitrous acid were produced with hydrogen peroxide. The decomposition rates of urea with and without hydrogen peroxide were represented by the first order reaction kinetics. The addition of hydrogen peroxide increased the rates at lower temperatures, but was scarcely effective at higher temperatures. In the absence of hydrogen peroxide, the effects of various additives at concentrations of 0.5 mol L(-1) on the decomposition rates at 649 K were examined. The addition of NaOH enhanced them remarkably. The presence of NaCl did not affect the product distribution significantly, but enhanced the rates somewhat, in particular, increasing as approaching to the critical temperature of water. The addition of acids, hydrogen chloride and sulfuric acid, did not increase the rates.

DOI： 10.1007/s10853-007-2027-6

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記述言語：英語   出版者・発行元：SPRINGER  

Urea was decomposed in sub- and supercritical water in the presence and the absence of hydrogen peroxide at temperatures from 538 to 651 K, 23 MPa and residence times up to 1.5 s in a continuous flow reactor. The initial concentrations of urea varied from 0.005 to 0.5 mol L(-1). The major products were carbon dioxide, and ammonia. As a minor product cyanic acid was detected without hydrogen peroxide, and nitric acid and nitrous acid were produced with hydrogen peroxide. The decomposition rates of urea with and without hydrogen peroxide were represented by the first order reaction kinetics. The addition of hydrogen peroxide increased the rates at lower temperatures, but was scarcely effective at higher temperatures. In the absence of hydrogen peroxide, the effects of various additives at concentrations of 0.5 mol L(-1) on the decomposition rates at 649 K were examined. The addition of NaOH enhanced them remarkably. The presence of NaCl did not affect the product distribution significantly, but enhanced the rates somewhat, in particular, increasing as approaching to the critical temperature of water. The addition of acids, hydrogen chloride and sulfuric acid, did not increase the rates.

DOI： 10.1007/s10853-007-2027-6

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記述言語：英語  

Two kinds of tracer response measurements, by the Taylor dispersion method using a stainless-steel diffusion column and the chromatographic impulse response (CIR) method using a polymer-coated diffusion column, were carried out by using the curve fitting to determine infinite-dilution binary diffusion coefficients of vitamin K3 (2-methylnaphthalene-1,4-dione), as a medium polar compound, in supercritical CO2 at 308.2 K and pressures from 7.75 to 31.00 MPa. The response curves in the Taylor dispersion method showed more significantly tailing closer to the critical point, whereas those did not at conditions away from the critical point. However, the CIR method provided the response curves almost without tailing over an entire range of pressure studied. Consequently, in the CIR method the response curves were accurately reproduced with the determined values of two parameters, binary diffusion coefficient and retention factor. The determined values of diffusion coefficients showed a little slow-down in the near critical region. In the Taylor dispersion method, however, the response curves with tailing were poorly reproduced with the determined values of diffusion coefficients, which apparently led to a steep-down in the near critical region. © 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2007.09.021

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記述言語：英語   出版者・発行元：SPRINGER  

The naturally occurring polysaccharides, starch and pectic acid, were hydrothermally degraded in a semi-batch reactor coupled with a plug-flow reactor (PFR) to produce valuable chemicals including mono- and oligosaccharides over a temperature range from 160 to 240 degrees C at 10 MPa. The solid polysaccharide samples were solubilized in a semi-batch reactor, and the water-soluble (WS) components instantly entered the PFR in which further degradation took place. The reaction temperature and/or residence time in the PFR significantly affected the yields of oligosaccharides, monosaccharides and secondary decomposition products, and also the average molecular weight of WS components. The product distributions were expressed with severity, which combines the effects of temperature and time on the progress of the reaction, as a single reaction parameter. Using this parameter, it was found that similar product distributions were obtained at equal levels of severity. The severity parameter enabled easy interpretation of the change in product distribution for these reactions.

DOI： 10.1007/s10853-007-2014-y

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記述言語：英語   出版者・発行元：SPRINGER  

Poly(vinyl chloride) (PVC) powder and commercial rigid PVC pipe were dechlorinated hydrothermally in the presence of alkalis such as ammonia, sodium hydroxide, and potassium hydroxide in a semi-batch flow reactor, with comparison to dechlorination using water alone. Aqueous ammonia was the most effective among these solvents. Dechlorination with aqueous ammonia proceeded in three stages: initial incubation, major dechlorination, and slow dechlorination. In the initial stage the rates were very slow and scarcely affected by temperature or ammonia concentration. In the second stage extensive dechlorination took place, and the rates were affected by temperature and ammonia concentration. These higher rates were found to be significantly influenced by swelling, not alkalinity, when these various alkalis solvents were compared. In the last stage the rates were slower than in the previous stage, and were not significantly dependent on temperature or ammonia concentration.

DOI： 10.1007/s10853-007-2015-x

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記述言語：英語   出版者・発行元：SPRINGER  

Poly(vinyl chloride) (PVC) powder and commercial rigid PVC pipe were dechlorinated hydrothermally in the presence of alkalis such as ammonia, sodium hydroxide, and potassium hydroxide in a semi-batch flow reactor, with comparison to dechlorination using water alone. Aqueous ammonia was the most effective among these solvents. Dechlorination with aqueous ammonia proceeded in three stages: initial incubation, major dechlorination, and slow dechlorination. In the initial stage the rates were very slow and scarcely affected by temperature or ammonia concentration. In the second stage extensive dechlorination took place, and the rates were affected by temperature and ammonia concentration. These higher rates were found to be significantly influenced by swelling, not alkalinity, when these various alkalis solvents were compared. In the last stage the rates were slower than in the previous stage, and were not significantly dependent on temperature or ammonia concentration.

DOI： 10.1007/s10853-007-2015-x

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Two kinds of tracer response measurements, by the Taylor dispersion method using a stainless-steel diffusion column and the chromatographic impulse response (CIR) method using a polymer-coated diffusion column, were carried out by using the curve fitting to determine infinite-dilution binary diffusion coefficients of vitamin K-3 (2-methylnaphthalene-1,4-dione), as a medium polar compound, in supercritical CO2 at 308.2 K and pressures from 7.75 to 31.00 MPa. The response curves in the Taylor dispersion method showed more significantly tailing closer to the critical point, whereas those did not at conditions away from the critical point. However, the CIR method provided the response curves almost without tailing over an entire range of pressure studied. Consequently, in the CIR method the response curves were accurately reproduced with the determined values of two parameters. binary diffusion coefficient and retention factor. The determined values of diffusion coefficients showed a little slow-down in the near critical region. In the Taylor dispersion method, however, the response curves with tailing were poorly reproduced with the determined values of diffusion coefficients, which apparently led to a steep-down in the near critical region. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2007.09.021

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Binary diffusion coefficients, D-12, of alpha-amino acids with hydroxyl groups, e.g., serine, threonine, allothreonine and homoserine, in dilute aqueous solutions were measured at six different temperatures from 293.2 to 333.2 K by the Taylor dispersion method. The determined D-12 values of serine and threonine at 298.2 K were in good agreement with the published data, whereas no data for allothreonine and homoserine is available in the literature. The D-12 values for each amino acid were well represented with the Stokes-Einstein equation by adjusting the molecular diameter. The D-12 values for amino acids containing hydroxyl groups, except for homoserine, were lower by approximately 5%, on the basis of the same solute molar volume, than those from the corresponding amino acids without hydroxyl groups. (c) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2007.10.013

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Binary diffusion coefficients, D-12, of alpha-amino acids with hydroxyl groups, e.g., serine, threonine, allothreonine and homoserine, in dilute aqueous solutions were measured at six different temperatures from 293.2 to 333.2 K by the Taylor dispersion method. The determined D-12 values of serine and threonine at 298.2 K were in good agreement with the published data, whereas no data for allothreonine and homoserine is available in the literature. The D-12 values for each amino acid were well represented with the Stokes-Einstein equation by adjusting the molecular diameter. The D-12 values for amino acids containing hydroxyl groups, except for homoserine, were lower by approximately 5%, on the basis of the same solute molar volume, than those from the corresponding amino acids without hydroxyl groups. (c) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2007.10.013

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Binary diffusion coefficients D-12 and retention factors k for dibenzo-24-crown-8 and 15-crown-5 ethers at 308.18 and 313.20 K, and vitamin K-1 at 313.20 K were measured in supercritical carbon dioxide by the chromatographic impulse response technique, and the effects of molecular shapes on the D-12 values were studied. At 313.2 K and 11.0 MPa the D-12 value of 15-crown-5 was higher than that predicted from the D-12 correlation with molecular weight MW over the range from 32 of methanol to 1138 of trinervonin reported in our previous studies, while the D-12 value of dibenzo-24-crown-8. disk shape molecule with MW=448.5, was almost in agreement with that of vitamin K-1, long chain molecule with MW=450.7, and with those predicted from the correlation. (c) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2007.01.035

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The reduction of sulfur content in gasoline and diesel fuel is a great environmental concern to reduce the motor vehicle emissions. Oxidative desulfurization using acetonitrile biphasic system has received much attention in recent years. The oxidative desulfurization can be oxidized the unreactive sulfur contents in the hydrodesulfurization and removed effectively. For the oxidative desulfurization process design and development, liquid-liquid equilibria (LLE) for acetonitrile biphasic systems are needed as fundamental information. In our previous work. LLE for acetonitrile+n-octane and+n-decane systems have been reported. In this work, therefore, LLE for acetonitrile+n-hexadecane system was measured. Furthermore, NRTL equation was applied to correlate the LLE for these three acetonitrile+n-alkane systems. (c) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2007.01.024

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The reduction of sulfur content in gasoline and diesel fuel is a great environmental concern to reduce the motor vehicle emissions. Oxidative desulfurization using acetonitrile biphasic system has received much attention in recent years. The oxidative desulfurization can be oxidized the unreactive sulfur contents in the hydrodesulfurization and removed effectively. For the oxidative desulfurization process design and development, liquid-liquid equilibria (LLE) for acetonitrile biphasic systems are needed as fundamental information. In our previous work. LLE for acetonitrile+n-octane and+n-decane systems have been reported. In this work, therefore, LLE for acetonitrile+n-hexadecane system was measured. Furthermore, NRTL equation was applied to correlate the LLE for these three acetonitrile+n-alkane systems. (c) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2007.01.024

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Binary diffusion coefficients D-12 and retention factors k for dibenzo-24-crown-8 and 15-crown-5 ethers at 308.18 and 313.20 K, and vitamin K-1 at 313.20 K were measured in supercritical carbon dioxide by the chromatographic impulse response technique, and the effects of molecular shapes on the D-12 values were studied. At 313.2 K and 11.0 MPa the D-12 value of 15-crown-5 was higher than that predicted from the D-12 correlation with molecular weight MW over the range from 32 of methanol to 1138 of trinervonin reported in our previous studies, while the D-12 value of dibenzo-24-crown-8. disk shape molecule with MW=448.5, was almost in agreement with that of vitamin K-1, long chain molecule with MW=450.7, and with those predicted from the correlation. (c) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2007.01.035

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The chromatographic impulse response technique with a polymer coated capillary column was applied to measurements of infinite dilution binary diffusion coefficients D and retention factors k in supercritical carbon dioxide by injecting a hexane solution dissolving a mixture of three unsaturated fatty acids such as alpha-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid. The coefficients were simultaneously estimated by the curve fitting analysis even from partially overlapping response curves with the resolution of 0.8. The D and k values for each solute were able to be so obtained as accurately as those determined by individually injecting a single component solution. Almost no effect of the interaction among the components in the mixture was found from various approaching ways for curve fitting and the consecutive injection of the mixture at a certain interval. (C) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2006.09.019

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The chromatographic impulse response technique with a polymer coated capillary column was applied to measurements of infinite dilution binary diffusion coefficients D and retention factors k in supercritical carbon dioxide by injecting a hexane solution dissolving a mixture of three unsaturated fatty acids such as alpha-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid. The coefficients were simultaneously estimated by the curve fitting analysis even from partially overlapping response curves with the resolution of 0.8. The D and k values for each solute were able to be so obtained as accurately as those determined by individually injecting a single component solution. Almost no effect of the interaction among the components in the mixture was found from various approaching ways for curve fitting and the consecutive injection of the mixture at a certain interval. (C) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2006.09.019

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Infinite dilution binary diffusion coefficients D-12 for arabinose, xylose, glucose, mannose, galactose, and sucrose in water were measured over the temperature range from (273.2 to 353.2) K at 0.1 MPa with the Taylor dispersion method. The values of D-12/T were well correlated with water viscosity for each solute with average absolute deviation AAD < 1.7 %. The accuracies for various predictive correlations were also examined.

DOI： 10.1021/je0601816

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Infinite dilution binary diffusion coefficients D-12 for arabinose, xylose, glucose, mannose, galactose, and sucrose in water were measured over the temperature range from (273.2 to 353.2) K at 0.1 MPa with the Taylor dispersion method. The values of D-12/T were well correlated with water viscosity for each solute with average absolute deviation AAD < 1.7 %. The accuracies for various predictive correlations were also examined.

DOI： 10.1021/je0601816

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記述言語：英語   出版者・発行元：JAPAN SOC ANALYTICAL CHEMISTRY  

The binary diffusion coefficients, D-12, and retention factors for myristoleic acid and its methyl ester at infinite dilution were measured by the chromatographic impulse response technique in supercritical carbon dioxide at temperatures of 313.2, 333.2 and 343.2 K and pressures from 9.2 to 30 MPa for the acid, and from 8.0 to 14 MPa for the ester. Although the D-12 values were represented by the two correlations, the D-12/T vs. CO2 viscosity and the Schmidt-number correlations, which are valid for more than 40 compounds that we have measured so far, significant temperature dependences were observed for the ester. Moreover, the D-12 values for the ester at 313.2 K downward deviated from the background values around 400 kg m(-3), where the partial molar volumes, obtained from the correlation between the retention factors measured and CO2 densities, showed large negative values.

DOI： 10.2116/analsci.22.1431

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記述言語：英語  

The binary diffusion coefficients, D12, and retention factors for myristoleic acid and its methyl ester at infinite dilution were measured by the chromatographic impulse response technique in supercritical carbon dioxide at temperatures of 313.2, 333.2 and 343.2 K and pressures from 9.2 to 30 MPa for the acid, and from 8.0 to 14 MPa for the ester. Although the D12 values were represented by the two correlations, the D12/T vs. CO2 viscosity and the Schmidt-number correlations, which are valid for more than 40 compounds that we have measured so far, significant temperature dependences were observed for the ester. Moreover, the D12 values for the ester at 313.2 K downward deviated from the background values around 400 kg m-3, where the partial molar volumes, obtained from the correlation between the retention factors measured and CO2 densities, showed large negative values. 2006 © The Japan Society for Analytical Chemistry.

DOI： 10.2116/analsci.22.1431

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DOI： 10.1021/je060149b

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Dr. Aydin Akgerman greatly contributed to studies on diffusion in liquids and supercritical fluids, in particular, measurements by the Taylor dispersion method. Based on his work, this article describes recent progress in measurements for binary diffusion coefficients in supercritical fluids by using the chromatographic impulse response technique as well as the Taylor dispersion method, and in the predictive empirical correlations. The data reported in the literature and the proposed correlations are also briefly reviewed together with the research subjects to be investigated in future. (c) 2006 Published by Elsevier B.V.

DOI： 10.1016/j.supflu.2006.02.016

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Dr. Aydin Akgerman greatly contributed to studies on diffusion in liquids and supercritical fluids, in particular, measurements by the Taylor dispersion method. Based on his work, this article describes recent progress in measurements for binary diffusion coefficients in supercritical fluids by using the chromatographic impulse response technique as well as the Taylor dispersion method, and in the predictive empirical correlations. The data reported in the literature and the proposed correlations are also briefly reviewed together with the research subjects to be investigated in future. (c) 2006 Published by Elsevier B.V.

DOI： 10.1016/j.supflu.2006.02.016

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Infinite dilution binary diffusion coefficients (D-12) were determined for 10 alpha-amino acids, glycine, alanine, alpha-aminonbutyric acid, norvaline, valine, norleucine, leucine, isoleucine, alloisoleucine, and tert-leucine in water over a temperature range from (293.2 to 333.2) K with the Taylor dispersion technique. At 298.2 K, the literature data for the two alpha-amino acids alloisoleucine and tert-leucine are not available, whereas the determined D-12 values of the others are in good agreement with the data reported previously within the experimental errors of +/- 2.0 %. The D-12 values for all alpha-amino acids studied were well-represented by two simple correlations, and the accuracies for the correlations were examined for each alpha-amino acid.

DOI： 10.1021/je060149b

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記述言語：英語   出版者・発行元：ELSEVIER SCI LTD  

Guar gum, a naturally occurring heteropolysaccharide made of mannose and galactose, was hydrolytically degraded without a catalyst in a batch reactor to produce water-soluble (WS) saccharides including mono- and oligosaccharides. The degradation was carried out under hydrothermal conditions over ranges of temperature from 180 to 240 degrees C and of reaction time from 3 to 60 min. Guar gum was readily dissolved and hydrolyzed, and the major products identified in the WS components were oligosaccharides with degrees of polymerization up to about 20, monosaccharides containing mannose and galactose, and 5-hydroxymethyl-2-furaldehyde (5-HMF). At 200 degrees C, the oligosaccharide yield, obtained from the difference between the yields of the total WS saccharides and monosaccharides, showed the highest value of 94.4% at 7 min among all conditions studied, on the basis of the saccharide content in the initial sample. The oligosaccharide yield decreased with reaction time, and the yield of monosaccharides correspondingly increased, and reached the highest value of 34.5% (mannose 22.8%, galactose 11.7%) at 60 min. The monosaccharides produced were further decomposed to secondary products such as 5-HMF. The maximum yield of 5-HMF obtained was 26.3% at 220 degrees C and 30 min. The production and the decomposition of galactose somewhat preceded those of mannose. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.carres.2006.02.014

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The chromatographic impulse response (CIR) method with curve fitting was employed for measuring binary diffusion coefficients D-12 at infinite dilution for polar compounds such as benzoic acid and C-1 to C-3 mono-alcohols in supercritical (SC) carbon dioxide at 313.2 K and pressures higher than 9.5 MPa. The measured D-12 values for the polar compounds were expressed with two correlations which well represent binary diffusion coefficients for non-polar and weak polarcompounds, i.e. the correlation of D-12/Tas a function of CO, viscosity and the Schmidt number correlation. Moreover, the slope was -0.5 in logarithmic plot of D-12 versus solute molecular weight over the range of molecular weight from 32 to 1138 at 313.2 K and 11.0 MPa. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2005.10.006

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The chromatographic impulse response (CIR) method with curve fitting was employed for measuring binary diffusion coefficients D-12 at infinite dilution for polar compounds such as benzoic acid and C-1 to C-3 mono-alcohols in supercritical (SC) carbon dioxide at 313.2 K and pressures higher than 9.5 MPa. The measured D-12 values for the polar compounds were expressed with two correlations which well represent binary diffusion coefficients for non-polar and weak polarcompounds, i.e. the correlation of D-12/Tas a function of CO, viscosity and the Schmidt number correlation. Moreover, the slope was -0.5 in logarithmic plot of D-12 versus solute molecular weight over the range of molecular weight from 32 to 1138 at 313.2 K and 11.0 MPa. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2005.10.006

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記述言語：英語   出版者・発行元：ELSEVIER SCI LTD  

Guar gum, a naturally occurring heteropolysaccharide made of mannose and galactose, was hydrolytically degraded without a catalyst in a batch reactor to produce water-soluble (WS) saccharides including mono- and oligosaccharides. The degradation was carried out under hydrothermal conditions over ranges of temperature from 180 to 240 degrees C and of reaction time from 3 to 60 min. Guar gum was readily dissolved and hydrolyzed, and the major products identified in the WS components were oligosaccharides with degrees of polymerization up to about 20, monosaccharides containing mannose and galactose, and 5-hydroxymethyl-2-furaldehyde (5-HMF). At 200 degrees C, the oligosaccharide yield, obtained from the difference between the yields of the total WS saccharides and monosaccharides, showed the highest value of 94.4% at 7 min among all conditions studied, on the basis of the saccharide content in the initial sample. The oligosaccharide yield decreased with reaction time, and the yield of monosaccharides correspondingly increased, and reached the highest value of 34.5% (mannose 22.8%, galactose 11.7%) at 60 min. The monosaccharides produced were further decomposed to secondary products such as 5-HMF. The maximum yield of 5-HMF obtained was 26.3% at 220 degrees C and 30 min. The production and the decomposition of galactose somewhat preceded those of mannose. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.carres.2006.02.014

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記述言語：英語   出版者・発行元：SPRINGER  

Acetamide and formamide were individually decomposed in a pressurized hot water in a tubular flow reactor at temperatures from 573 to 693 K, and pressure of 23 MPa, residence times up to 500 s, and the initial concentrations of both amides from 0.005 to 0.5 mol/L. The major products were ammonia and acetic acid from decomposition of acetamide, and ammonia and formic acid from that of formamide. Formic acid was further decomposed readily into carbon dioxide. Although the decomposition reactions for both amides were represented acceptably by the first order reaction kinetics, the rate constants increased with increasing the initial sample concentrations due to the autocatalytic effect. Apparently the second order reaction kinetics with respect to the concentration of each amide remained more represented the global decomposition rates, and the rate constants decreased with increasing the initial concentrations. The effects of hydrogen peroxide added on the global decomposition rates and the product yields were not evident: the addition slightly lowered the rates, but the major products were almost the same as those in the absence of hydrogen peroxide at temperatures lower than 653 K. Above 653 K more CO2 was produced. (c) 2006 Springer Science + Business Media, Inc.

DOI： 10.1007/s10853-006-4616-1

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記述言語：英語   出版者・発行元：SPRINGER  

Starch was hydrothermally degraded without any additives over the temperature range from 453 to 563 K at a constant pressure of 10 MPa and the fluid residence times up to 6 min in a semi-batch reactor to produce glucose and maltooligosaccharides. The effects of reaction temperature, flow rate of hot water and residence time of water-soluble components on the product distribution in the solvothermal degradation of starch were investigated. Even at the lowest reaction temperature studied, the loaded starch was partially degraded and dissolved within 8 min by contacting high-temperature and high-pressure water in a semi-batch reactor. By installing a plug-flow reactor at the exit of the first reactor to increase and control precisely the residence time, the maximum glucose yield of 43.8% on the carbon weight basis of the starting material was obtained at 3.64 min and 513 K. The comparison of yields of glucose and 5-hydroxymethyl furfural (HMF), which is a major secondary product, indicates that adjusting the residence time was the most effective to increase the glucose yield and to suppress the 5-HMF production. (c) 2006 Springer Science + Business Media, Inc.

DOI： 10.1007/s10853-006-7491-x

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記述言語：英語   出版者・発行元：SPRINGER  

Starch was hydrothermally degraded without any additives over the temperature range from 453 to 563 K at a constant pressure of 10 MPa and the fluid residence times up to 6 min in a semi-batch reactor to produce glucose and maltooligosaccharides. The effects of reaction temperature, flow rate of hot water and residence time of water-soluble components on the product distribution in the solvothermal degradation of starch were investigated. Even at the lowest reaction temperature studied, the loaded starch was partially degraded and dissolved within 8 min by contacting high-temperature and high-pressure water in a semi-batch reactor. By installing a plug-flow reactor at the exit of the first reactor to increase and control precisely the residence time, the maximum glucose yield of 43.8% on the carbon weight basis of the starting material was obtained at 3.64 min and 513 K. The comparison of yields of glucose and 5-hydroxymethyl furfural (HMF), which is a major secondary product, indicates that adjusting the residence time was the most effective to increase the glucose yield and to suppress the 5-HMF production. (c) 2006 Springer Science + Business Media, Inc.

DOI： 10.1007/s10853-006-7491-x

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記述言語：英語   出版者・発行元：SPRINGER  

Acetamide and formamide were individually decomposed in a pressurized hot water in a tubular flow reactor at temperatures from 573 to 693 K, and pressure of 23 MPa, residence times up to 500 s, and the initial concentrations of both amides from 0.005 to 0.5 mol/L. The major products were ammonia and acetic acid from decomposition of acetamide, and ammonia and formic acid from that of formamide. Formic acid was further decomposed readily into carbon dioxide. Although the decomposition reactions for both amides were represented acceptably by the first order reaction kinetics, the rate constants increased with increasing the initial sample concentrations due to the autocatalytic effect. Apparently the second order reaction kinetics with respect to the concentration of each amide remained more represented the global decomposition rates, and the rate constants decreased with increasing the initial concentrations. The effects of hydrogen peroxide added on the global decomposition rates and the product yields were not evident: the addition slightly lowered the rates, but the major products were almost the same as those in the absence of hydrogen peroxide at temperatures lower than 653 K. Above 653 K more CO2 was produced. (c) 2006 Springer Science + Business Media, Inc.

DOI： 10.1007/s10853-006-4616-1

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Infinite dilution binary diffusion coefficients D-12 and retention factors k for gamma-linolenic acid were measured by chromatographic impulse response technique in supercritical carbon dioxide over the ranges of temperature from 308 to 343 K and pressure from 9 to 30 MPa, together with those for the methyl and ethyl esters at 313 and 343 K and pressures from 8 to 16 MPa. In comparison with literature values for C18 free fatty acids and the esters. the differences in D-12 data were almost indiscernible for each isomer group: alpha- and gamma-linolenic acid, oleic and elaidic acids, oleic and elaidic acid methyl esters, and their ethyl esters. The number of carbon double bonds did not affect the D-12 values significantly. Moreover, the differences in the values between free fatty acid and the ester forms were also small, whereas the D-12 values increased in order of acid to ethyl ester to methyl ester. The validities of the predictive correlations we had proposed such as the D-12/T-CO2 viscosity and the Schmidt number correlation were verified. The retention factor k values for the acid form were much higher than those for the methyl and ethyl esters. The k values were correlated with temperature and CO2 density for each compound, and the solute partial molar volumes were determined from the k-CO2 density correlation. (C) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2005.08.001

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Infinite dilution binary diffusion coefficients D-12 and retention factors k for gamma-linolenic acid were measured by chromatographic impulse response technique in supercritical carbon dioxide over the ranges of temperature from 308 to 343 K and pressure from 9 to 30 MPa, together with those for the methyl and ethyl esters at 313 and 343 K and pressures from 8 to 16 MPa. In comparison with literature values for C18 free fatty acids and the esters. the differences in D-12 data were almost indiscernible for each isomer group: alpha- and gamma-linolenic acid, oleic and elaidic acids, oleic and elaidic acid methyl esters, and their ethyl esters. The number of carbon double bonds did not affect the D-12 values significantly. Moreover, the differences in the values between free fatty acid and the ester forms were also small, whereas the D-12 values increased in order of acid to ethyl ester to methyl ester. The validities of the predictive correlations we had proposed such as the D-12/T-CO2 viscosity and the Schmidt number correlation were verified. The retention factor k values for the acid form were much higher than those for the methyl and ethyl esters. The k values were correlated with temperature and CO2 density for each compound, and the solute partial molar volumes were determined from the k-CO2 density correlation. (C) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.supflu.2005.08.001

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Polysaccharides such as agar, guar gum, starch, and xylan were hydrolyzed to produce mono- and oligosaccharides under hydrothermal conditions with and without carbon dioxide in a small batch reactor. The molecular weight distributions of the polysaccharide hydrolyzates shifted to lower molecular weights by increasing the carbon dioxide load, corresponding to higher pressures of carbon dioxide. For example, the yield of glucose produced from the hydrolysis of starch at 200 degrees C was increased significantly from 3.7% to 53.0% (on a carbon weight basis) of the initial polysaccharide by increasing carbon dioxide load in a reaction time of 15 min. Carbonic acid generated from water and carbon dioxide appeared to lower the pH of high-temperature and high-pressure water. Polysaccharide hydrolysis under hydrothermal conditions in the presence of carbon dioxide is an environmentally benign method to produce mono- and oligosaccharides because the process does not require the use of conventional acids and bases followed by neutralization and separation.

DOI： 10.1021/bp050214q

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Polysaccharides such as agar, guar gum, starch, and xylan were hydrolyzed to produce mono- and oligosaccharides under hydrothermal conditions with and without carbon dioxide in a small batch reactor. The molecular weight distributions of the polysaccharide hydrolyzates shifted to lower molecular weights by increasing the carbon dioxide load, corresponding to higher pressures of carbon dioxide. For example, the yield of glucose produced from the hydrolysis of starch at 200 degrees C was increased significantly from 3.7% to 53.0% (on a carbon weight basis) of the initial polysaccharide by increasing carbon dioxide load in a reaction time of 15 min. Carbonic acid generated from water and carbon dioxide appeared to lower the pH of high-temperature and high-pressure water. Polysaccharide hydrolysis under hydrothermal conditions in the presence of carbon dioxide is an environmentally benign method to produce mono- and oligosaccharides because the process does not require the use of conventional acids and bases followed by neutralization and separation.

DOI： 10.1021/bp050214q

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記述言語：英語   出版者・発行元：Universitatsverlag Karlsruhe  

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記述言語：英語  

Infinite dilution binary diffusion coefficients D12 and retention factors k have been measured in supercritical carbon dioxide for the long-chain triglyceride triarachidonin at 313.2 K at (10 to 30) MPa, and trierucin and trinervonin both at 308.2 K to 323.2 K over the pressure range from (9 to 30) MPa by the Chromatographic impulse response method. It was found that the D12 predictive correlations proposed previously, D 12/T as a function of viscosity and the Schmidt number correlations, were valid for such long-chain triglycerides having molecular weights near or over 1000. Furthermore, partial molar volumes of the solutes were determined from the relationships between k and CO2 density. © 2005 American Chemical Society.

DOI： 10.1021/je050101i

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記述言語：英語  

Infinite dilution binary diffusion coefficients D12 and retention factors k have been measured in supercritical carbon dioxide for the long-chain triglyceride triarachidonin at 313.2 K at (10 to 30) MPa, and trierucin and trinervonin both at 308.2 K to 323.2 K over the pressure range from (9 to 30) MPa by the Chromatographic impulse response method. It was found that the D12 predictive correlations proposed previously, D 12/T as a function of viscosity and the Schmidt number correlations, were valid for such long-chain triglycerides having molecular weights near or over 1000. Furthermore, partial molar volumes of the solutes were determined from the relationships between k and CO2 density. © 2005 American Chemical Society.

DOI： 10.1021/je050101i

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記述言語：英語   出版者・発行元：Universitatsverlag Karlsruhe  

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記述言語：英語   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

To determine binary diffusion coefficients from tracer response measurements with a coiled capillary column (curved tube) at relatively high flow rates, a conversion formula to correct for the secondary flow effect was derived from the second central moment of the impulse response curve. Its practical expression was obtained analytically by the perturbation method up to lambda(10), where lambda is the ratio of the tube radius to the coil radius. The reliability of the correction was evaluated by an alternative series of lambda. As a result, the effective range of DeSc(1/2) < 8-9.5 without correction widened to DeSc(1/2) < 18-19 to determine the diffusion coefficient within 1% error. Applicability of the correction was demonstrated for phenol and ubiquinone CoQ10 using a coated column, and for benzene using an uncoated column (the Taylor dispersion), in supercritical carbon dioxide at 16-17 MPa and 313.15 K. (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ces.2004.03.033

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記述言語：英語  

A noise elimination technique was applied to the determination of binary diffusion coefficients D12 from the response curves having extremely low absorbance intensities in impulse response methods under supercritical conditions of carbon dioxide. The effectiveness of this technique was experimentally examined for the analyses of response curves through both the curve-fitting and the moment methods in two cases: the chromatographic impulse response method for phenol and β-carotene with a polymer-coated capillary column, and the Taylor dispersion method for acetone with an uncoated capillary column. Unreliable D12 values were obtained from the moment method of the response curves at lower absorbance intensities, even treated with noise elimination. The curve-fitting method with the noise elimination treatment was quite effective for determining the D12 values accurately, and was valid at the lowest absorbance intensities, on the order of 10-4 absorbance unit of UV-Vis multi-detector, corresponding to the smallest quantity of the solute, i.e. 6×10-5, 6×10-6, and 5×10-2 μ mol for phenol, β-carotene, and acetone, respectively, under conditions studied. Infinite dilution regions for binary diffusion coefficients were obtained by injecting various amounts: the binary diffusion coefficients showed constant values at concentrations less than 0.6, 0.004, and 0.08 mol m-3 for phenol, β-carotene, and acetone, respectively, in supercritical carbon dioxide at 313.2 K and 16-18 MPa. © 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2004.04.005

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

A noise elimination technique was applied to the determination of binary diffusion coefficients D-12 from the response curves having extremely low absorbance intensities in impulse response methods under supercritical conditions of carbon dioxide. The effectiveness of this technique was experimentally examined for the analyses of response curves through both the curve-fitting and the moment methods in two cases: the chromatographic impulse response method for phenol and beta-carotene with a polymer-coated capillary column, and the Taylor dispersion method for acetone with an uncoated capillary column. Unreliable D-12 values were obtained from the moment method of the response curves at lower absorbance intensities, even treated with noise elimination. The curve-fitting method with the noise elimination treatment was quite effective for determining the D-12 values accurately, and was valid at the lowest absorbance intensities, on the order of 10(-4) absorbance unit of UV-Vis multi-detector, corresponding to the smallest quantity of the solute, i.e. 6 x 10(-5), 6 x 10(-6), and 5 x 10(-2) mu mol for phenol, beta-carotene, and acetone, respectively, under conditions studied. Infinite dilution regions for binary diffusion coefficients were obtained by injecting various amounts: the binary diffusion coefficients showed constant values at concentrations less than 0.6, 0.004, and 0.08 mol m(-3) for phenol, beta-carotene, and acetone, respectively, in supercritical carbon dioxide at 313.2 K and 16-18 MPa. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2004.04.005

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記述言語：英語   出版者・発行元：Elsevier  

DOI： 10.1016/j.ces.2004.03.033

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記述言語：英語   掲載種別：書評論文，書評，文献紹介等  

This review describes impulse response techniques with a curve-fitting method to measure thermodynamic properties, such as binary diffusion coefficient, retention factor, and partial molar volume, under supercritical conditions. Theoretical background, parameter sensitivity, sources of experimental error, noise elimination technique, and the correction of apparent binary diffusion coefficients due to column coiling are discussed based on recent studies, together with data sources and predictive correlations for binary diffusion coefficients. © 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2004.03.043

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記述言語：英語  

The theoretical basis of a Gaussian-like approximate solution was applied to a chromatographic impulse response technique with curve fitting for measuring binary diffusion coefficients and retention factors using a polymer-coated capillary column. The formulae were derived for evaluating both the accuracy of the approximate solution and the sensitivity of the parameters. The validity of the solution also was confirmed experimentally for pulse injection of phenol in acetone into supercritical carbon dioxide flowing at 313.15K and 11.6-28.6MPa. Potential sources for experimental errors of the method are discussed. © 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2004.02.067

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記述言語：英語   掲載種別：書評論文，書評，文献紹介等   出版者・発行元：ELSEVIER SCIENCE BV  

This review describes impulse response techniques with a curve-fitting method to measure thermodynamic properties, such as binary diffusion coefficient. retention factor, and partial molar volume, under supercritical conditions. Theoretical background, parameter sensitivity, sources of experimental error, noise elimination technique, and the correction of apparent binary diffusion coefficients due to column coiling are discussed based on recent studies, together with data sources and predictive correlations for binary diffusion coefficients. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.chroma.2004.03.043

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Infinite dilution binary diffusion coefficients and retention factors for the oleic acid family such as oleic acid, methyl- and ethyl esters, and mono-, di, and triglycerides at 313.21 K and 8-30 MPa, and for other 13 lipids consisting of C18-C22 unsaturated fatty acid constituents at 313.21 K and 11 MPa were measured in carbon dioxide by a chromatographic impulse response method with a polymer coated capillary column. The binary diffusion coefficients and the retention factors for each compound decreased with increasing pressure. The binary diffusion coefficients could be represented by a Schmidt number correlation and by an empirical equation written in terms of temperature and CO2 viscosity. The retention factors for each solute could be expressed in terms of CO2 density. While the binary diffusion coefficients at 313.21 K and 11 MPa decreased with solute molecular weight, those for compounds having the same carbon numbers in each group, such as methyl ester, ethyl ester, and triglyceride, decreased with increasing the number of C-C double bonds. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2004.01.017

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Infinite dilution binary diffusion coefficients and retention factors for the oleic acid family such as oleic acid, methyl- and ethyl esters, and mono-, di, and triglycerides at 313.21 K and 8-30 MPa, and for other 13 lipids consisting of C18-C22 unsaturated fatty acid constituents at 313.21 K and 11 MPa were measured in carbon dioxide by a chromatographic impulse response method with a polymer coated capillary column. The binary diffusion coefficients and the retention factors for each compound decreased with increasing pressure. The binary diffusion coefficients could be represented by a Schmidt number correlation and by an empirical equation written in terms of temperature and CO2 viscosity. The retention factors for each solute could be expressed in terms of CO2 density. While the binary diffusion coefficients at 313.21 K and 11 MPa decreased with solute molecular weight, those for compounds having the same carbon numbers in each group, such as methyl ester, ethyl ester, and triglyceride, decreased with increasing the number of C-C double bonds. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fluid.2004.01.017

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

A monosaccharide of galacturonic acid and its oligomers were produced by hydrolysis of poly(galacturonic acid)s with water in the absence of any additives in a semibatch flow reactor over the temperature range from 453 to 533 K at 10 MPa. A solid sample of poly(galacturonic acid) was fixed in the reactor, and the residence times of water in the reactor were estimated to be less than a few seconds. At 493 K and a heating time of 2 min, 79 wt % of the initial sample on the carbon weight basis was converted into water-soluble components, which consisted of monomer and oligomers having various degrees of polymerization (DP) and were enzymatically hydrolyzable into mono(galacturonic acid), the dimer, and the trimer. The maximum yields of monomer and oligomers with DP = 2-10 were 11.4 and 22.1 wt %, respectively, on the carbon weight basis of the initial sample at 533 K, 10 MPa, and a heating time of 2 min. The yield of each product was correlated with the content of organic carbon in the eluted product solution. The formation of the further decomposed products such as furfural and gaseous products was insignificant under the hydrolysis conditions studied.

DOI： 10.1021/ie0202672

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

A monosaccharide of galacturonic acid and its oligomers were produced by hydrolysis of poly(galacturonic acid)s with water in the absence of any additives in a semibatch flow reactor over the temperature range from 453 to 533 K at 10 MPa. A solid sample of poly(galacturonic acid) was fixed in the reactor, and the residence times of water in the reactor were estimated to be less than a few seconds. At 493 K and a heating time of 2 min, 79 wt % of the initial sample on the carbon weight basis was converted into water-soluble components, which consisted of monomer and oligomers having various degrees of polymerization (DP) and were enzymatically hydrolyzable into mono(galacturonic acid), the dimer, and the trimer. The maximum yields of monomer and oligomers with DP = 2-10 were 11.4 and 22.1 wt %, respectively, on the carbon weight basis of the initial sample at 533 K, 10 MPa, and a heating time of 2 min. The yield of each product was correlated with the content of organic carbon in the eluted product solution. The formation of the further decomposed products such as furfural and gaseous products was insignificant under the hydrolysis conditions studied.

DOI： 10.1021/ie0202672

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The theoretical basis of a Gaussian-like approximate solution was applied to a chromatographic impulse response technique with curve fitting for measuring binary diffusion coefficients and retention factors using a polymer-coated capillary column. The formulae were derived for evaluating both the accuracy of the approximate solution and the sensitivity of the parameters. The validity of the solution also was confirmed experimentally for pulse injection of phenol in acetone into supercritical carbon dioxide flowing at 313.15 K and 11.6-28.6 MPa. Potential sources for experimental errors of the method are discussed. (C) 2004 Elsevier B.V All rights reserved.

DOI： 10.1016/j.chroma.2004.02.067

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記述言語：英語   出版者・発行元：JOHN WILEY & SONS LTD  

Starch was converted into glucose by hydrolysis with water under hydrothermal conditions at 453 - 513 K in a small batch reactor. The major product was glucose; oligomers having various degrees of polymerization, maltose, fructose, 5-hydroxymethylfurfural and furfural were also produced. The maximum yield of glucose obtained was 630 g kg(-1) on the carbon basis at 473 K and 30 min, where the quantity of carbon unrecovered was about 50 g kg(-1), and the production of char and gaseous products was negligible. (C) 2004 Society of Chemical Industry.

DOI： 10.1002/jctb.976

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記述言語：英語   出版者・発行元：JOHN WILEY & SONS LTD  

Starch was converted into glucose by hydrolysis with water under hydrothermal conditions at 453 - 513 K in a small batch reactor. The major product was glucose; oligomers having various degrees of polymerization, maltose, fructose, 5-hydroxymethylfurfural and furfural were also produced. The maximum yield of glucose obtained was 630 g kg(-1) on the carbon basis at 473 K and 30 min, where the quantity of carbon unrecovered was about 50 g kg(-1), and the production of char and gaseous products was negligible. (C) 2004 Society of Chemical Industry.

DOI： 10.1002/jctb.976

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DOI： 10.4131/jshpreview.14.4

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記述言語：日本語   掲載種別：書評論文，書評，文献紹介等   出版者・発行元：Japan Society of High Pressure Science and Technology  

The chromatographic impulse response technique with the curve fitting method is a useful tool to measure binary diffusion coefficient under supercritical conditions. Based on our recent measurement data, the effectiveness of the simple predictive correlations such as the D 12-viscosity correlation and the Schmidt number correlation is presented. Moreover, the sensitivities of the parameters determined and sources of experimental error are discussed.

DOI： 10.4131/jshpreview.14.4

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記述言語：英語  

DOI： 10.1016/S0896-8446(02)00209-7

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記述言語：英語  

Binary diffusion coefficients D12 and partition ratios k at infinite dilution for β-carotene and α-tocopherol in supercritical carbon dioxide were measured at temperatures from 308.15 to 333.15 K and pressures from 9 to 30 MPa by a tracer response technique with a poly(ethylene glycol) coated capillary column. Both parameters, simultaneously determined by fitting the calculated response curve to that measured experimentally, were well represented with the correlations: the D12/T values were correlated with CO2 viscosity, and the k values were expressed with a function of temperature and CO2 density. However, the partial molar volumes obtained from the k values were not well consistent with those estimated using equation of states having the interaction parameters k ij reported in the literature. © 2002 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0896-8446(02)00209-7

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

The binary diffusion coefficient D-12 and partition ratio k were measured for two omega6 group compounds, linoleic acid and arachidonic acid, at infinite dilution in carbon dioxide at temperatures from 308.15 K to 343.15 K and pressures from 9 MPa to 30 MPa by a tracer response technique with a poly(ethylene glycol)-coated capillary column. The measured D-12 values were well represented by a correlation of D-12/T versus CO2 viscosity and by the Schmidt number correlation for each solute, and the k values were well represented as a function of temperature and CO2 density. Partial molar volumes were also obtained from the k values.

DOI： 10.1021/je020205i

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

The binary diffusion coefficient D-12 and partition ratio k were measured for two omega6 group compounds, linoleic acid and arachidonic acid, at infinite dilution in carbon dioxide at temperatures from 308.15 K to 343.15 K and pressures from 9 MPa to 30 MPa by a tracer response technique with a poly(ethylene glycol)-coated capillary column. The measured D-12 values were well represented by a correlation of D-12/T versus CO2 viscosity and by the Schmidt number correlation for each solute, and the k values were well represented as a function of temperature and CO2 density. Partial molar volumes were also obtained from the k values.

DOI： 10.1021/je020205i

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記述言語：英語  

DOI： 10.1016/S0378-3812(02)00309-6

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

A tracer response technique with a poly(ethylene glycol) coated capillary column was employed to measure binary diffusion coefficient and partition ratio for the omega3 group of long chain unsaturated fatty acids such as docosahexaenoic acid, eicosapentaenoic acid and a-linolenic acid at infinite dilution in supercritical (SC) carbon dioxide at temperatures from 308.15 to 343.15 K and pressures from 9 to 30 MPa. The binary diffusion coefficients for each solute were expressed with the Schmidt number correlation as well as the correlation with temperature and CO2 viscosity. The partition ratios were correlated with temperature and CO2 density. Moreover, the partial molar volumes were obtained from the partition ratios for each solute. (C) 2002 Elsevier Science B.V All rights reserved.

DOI： 10.1016/S0378-3812(02)00309-6

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記述言語：英語   出版者・発行元：American Chemical Society  

Infinite-dilution binary diffusion coefficient D12 and partition ratio k for ubiquinone CoQ10 in carbon dioxide were measured by a tracer response technique with a poly(ethylene glycol)-coated capillary column at temperatures from 308.15 to 333.15 K and pressures from 8.5 to 30 MPa. D12 and k values were simultaneously determined from a measured response curve by the curvefitting method. The fitting error between measured and calculated response curves increased with decreasing pressure, as had been the case in our previous studies on various solutes in supercritical CO2 by the Taylor dispersion method. The D12 values were correlated with temperature and CO2 viscosity and the k values with temperature and CO2 density. Moreover, partial molar volumes of CoQ10 in supercritical CO2 were obtained from the k values.

DOI： 10.1021/ie0109096

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Infinite-dilution binary diffusion coefficient D-12 and partition ratio k for ubiquinone CoQ10 in carbon dioxide were measured by a tracer response technique with a poly(ethylene glycol)-coated capillary column at temperatures from 308.15 to 333.15 K and pressures from 8.5 to 30 MPa. D12 and k values were simultaneously determined from a measured response curve by the curve-fitting method. The fitting error between measured and calculated response curves increased with decreasing pressure, as had been the case in our previous studies on various solutes in supercritical CO2 by the Taylor dispersion method. The D12 values were correlated with temperature and CO2 viscosity and the k values with temperature and CO2 density. Moreover, partial molar volumes of CoQ10 in supercritical CO2 were obtained from the k values.

DOI： 10.1021/ie0109096

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記述言語：英語  

Binary diffusion coefficients (D12) for low volatile compounds such as Vitamin K3, ubiquinone (UQ-10), α-tocopherol, β-carotene, and phenol in supercritical carbon dioxide were measured by the Taylor dispersion method with two columns connected in series: a poly(ethylene glycol) (PEG) coated capillary column followed by a stainless steel uncoated capillary column, at 313.15K and pressures from 9 to 30MPa. The tracer species dissolved with a common organic solvent such as hexane or chloroform was injected to the diffusion column as a delta shot through an ordinary HPLC injector. The response curve measured at the exit of the first column, coated with PEG, was regarded as an input signal, and that measured at the exit of the second column made of the uncoated stainless steel tubing as the output signal. The tracer species and the organic solvent were separated during flowing in the first column. The output response signal was calculated from the input signal and the inverse Laplace transform of the transfer function through the convolution integral. The D12 values were determined by fitting the calculated output curve to that measured experimentally. The measured D12 values were fully consistent with those measured with the PEG coated capillary column for one point measurement reported [Ind. Eng. Chem. Res. 39 (2000) 4462]. This two-point measurements with the two columns were adequate for measuring D12 values for low volatile compounds in supercritical fluids. © 2002 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0378-3812(01)00717-8

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Binary diffusion coefficients (D-12) for low volatile compounds such as Vitamin K-3. ubiquinone (UQ-10), alpha-tocopherol, beta-carotene, and phenol in supercritical carbon dioxide were measured by the Taylor dispersion method with two columns connected in series: a poly(ethylene glycol) (PEG) coated capillary column followed by a stainless steel uncoated capillary column. at 313.15 K and pressures from 9 to 30 MPa. The tracer species dissolved with a common organic solvent such as hexane or chloroform was injected to the diffusion column as a delta shot through an ordinary HPLC injector. The response curve measured at the exit of the first column, coated with PEG. was regarded as an input signal, and that measured at the exit of the second column made of the uncoated stainless steel tubing as the output signal. The tracer species and the organic solvent were separated during flowing in the first column. The output response signal was calculated from the input signal and the inverse Laplace transform of the transfer function through the convolution integral. The D-12 values were determined by fitting the calculated output curve to that measured experimentally. The measured D-12 values were fully consistent with those measured with the PEG coated capillary column for one point measurement reported [Ind. Eng. Chem. Res. 39 (2000) 4462]. This two-point measurements with the two columns were adequate for measuring D-12 values for low volatile compounds in supercritical fluids. (C) 2002 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0378-3812(01)00717-8

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記述言語：英語   出版者・発行元：GEORG THIEME VERLAG KG  

The rare earth(III) salt catalyzed asymmetric Diels-Alder reaction of cyclopentadiene with a chiral dienophile in super-critical carbon dioxide (scCO(2)) proceeded rapidly to give the adduct with a higher diastereoselectivity than that in dichloromethane; optimization of the CO2 density increased the de value up to 77%.

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記述言語：英語   出版者・発行元：GEORG THIEME VERLAG KG  

The rare earth(III) salt catalyzed asymmetric Diels-Alder reaction of cyclopentadiene with a chiral dienophile in super-critical carbon dioxide (scCO(2)) proceeded rapidly to give the adduct with a higher diastereoselectivity than that in dichloromethane; optimization of the CO2 density increased the de value up to 77%.

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記述言語：英語   出版者・発行元：KLUWER ACADEMIC/PLENUM PUBL  

Infinite dilution binary diffusion coefficients, D-12, of benzene in carbon dioxide were measured by the Taylor dispersion technique at temperatures from 308.15 to 328.15 K and pressures from 6 to 30 MPa. The diffusion coefficients were obtained by the method of fitting in the time domain from the response curves measured with a UV vis multidetector by scanning from 220 to 280 nm at increments of I or 4 rim. The wavelength dependences on the binary diffusion coefficient and the uncertainty were examined. The detector linearity, in terms of the relationship between the absorbance intensity and the product of the peak area of the response curve and CO2 velocity, was found to fail at some characteristic absorption wavelengths such as 243, 248, 253, and 259 nm, even when the maximum absorbance intensities of the response curves were less than 0.5 and the fits were good. Although the D-12 values obtained from the response curves measured at 253 nm were almost consistent with some literature data, the D-12 values measured at wavelengths showing the detector linearity to be satisfactory, i.e., at 239 nm, were higher than those at 253 nm. The present D-12 data at 239 nm were well represented by the Sclimidt number correlation, except for those showing the anomalous decrease in a plot of D-12 vs density in the density range from 250 to 500 kg (.) m(-3).

DOI： 10.1023/A:1013178614497

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記述言語：英語   出版者・発行元：KLUWER ACADEMIC/PLENUM PUBL  

Infinite dilution binary diffusion coefficients, D-12, of benzene in carbon dioxide were measured by the Taylor dispersion technique at temperatures from 308.15 to 328.15 K and pressures from 6 to 30 MPa. The diffusion coefficients were obtained by the method of fitting in the time domain from the response curves measured with a UV vis multidetector by scanning from 220 to 280 nm at increments of I or 4 rim. The wavelength dependences on the binary diffusion coefficient and the uncertainty were examined. The detector linearity, in terms of the relationship between the absorbance intensity and the product of the peak area of the response curve and CO2 velocity, was found to fail at some characteristic absorption wavelengths such as 243, 248, 253, and 259 nm, even when the maximum absorbance intensities of the response curves were less than 0.5 and the fits were good. Although the D-12 values obtained from the response curves measured at 253 nm were almost consistent with some literature data, the D-12 values measured at wavelengths showing the detector linearity to be satisfactory, i.e., at 239 nm, were higher than those at 253 nm. The present D-12 data at 239 nm were well represented by the Sclimidt number correlation, except for those showing the anomalous decrease in a plot of D-12 vs density in the density range from 250 to 500 kg (.) m(-3).

DOI： 10.1023/A:1013178614497

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記述言語：日本語   出版者・発行元：環境科学会  

DOI： 10.11353/sesj1988.14.359

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記述言語：日本語   出版者・発行元：環境科学会  

DOI： 10.11353/sesj1988.14.333

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00075012724?from=CiNii

記述言語：日本語  

Binary diffusion coefficients, D12, and partition ratios for polymer layer to supercritical fluid, k, for phenol in supercritical carbon dioxide were measured in the ranges of temperatures from 308.15 to 328.15 K and pressures from 8.7to 30 MPa, by using a tracer response technique with a polyethylene-glycol coated capillary column. The values of two parameters, D12 and k, were determined by fitting in the time domain the calculated response curve with assumed values of the two parameters to that measured experimentally, instead of the moment method which has been used commonly. The D12 and k values at each temperature decreased simply with increasing pressure. The D12 values were well correlated with the Schmidt number correlation. The parameter sensitivities in the D12 and k values were also examined.【査読有】

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Binary diffusion coefficients, D-12, and partition ratios, k, for the poly(ethylene glycol) (PEG) layer to supercritical carbon dioxide for acetone and some solid solutes such as phenol, alpha -tocopherol, and beta -carotene were measured with a PEG-coated capillary column by a tracer response technique. The D-12 values for acetone with the PEG-coated column were consistent with those measured by the Taylor dispersion method in which an uncoated capillary column was employed. The D-12 and k values for all of the solutes decrease simply with increasing pressure, and the D-12 values were represented by the Schmidt number correlation.

DOI： 10.1021/ie000201b

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Binary diffusion coefficients, D-12, and partition ratios, k, for the poly(ethylene glycol) (PEG) layer to supercritical carbon dioxide for acetone and some solid solutes such as phenol, alpha -tocopherol, and beta -carotene were measured with a PEG-coated capillary column by a tracer response technique. The D-12 values for acetone with the PEG-coated column were consistent with those measured by the Taylor dispersion method in which an uncoated capillary column was employed. The D-12 and k values for all of the solutes decrease simply with increasing pressure, and the D-12 values were represented by the Schmidt number correlation.

DOI： 10.1021/ie000201b

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記述言語：英語  

Infinite-dilution binary diffusion coefficients of 2-propanone, 2-butanone, 2-pentanone, and 3-pentanone in carbon dioxide were measured by the Taylor dispersion method at temperatures from 308.15 to 328.15 K and pressures from 7.60 to 34.57 MPa. The D12 values were obtained from the response curves by the method of fitting in the time domain. The accuracy in the fitting error was examined for each measurement. The measured D12 data were found to be well correlated by the Schmidt number correlation, with AAD% = 3.74% for all solutes.

DOI： 10.1023/A:1006749309979

Scopus

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記述言語：英語  

Infinite-dilution binary diffusion coefficients of 2-propanone, 2-butanone, 2-pentanone, and 3-pentanone in carbon dioxide were measured by the Taylor dispersion method at temperatures from 308.15 to 328.15 K and pressures from 7.60 to 34.57 MPa. The D12 values were obtained from the response curves by the method of fitting in the time domain. The accuracy in the fitting error was examined for each measurement. The measured D12 data were found to be well correlated by the Schmidt number correlation, with AAD% = 3.74% for all solutes.

DOI： 10.1023/A:1006749309979

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DOI： 10.1016/S0921-0423(00)80033-7

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記述言語：英語   出版者・発行元：Kluwer Academic/Plenum Publ Corp  

Binary diffusion coefficients of acetone in carbon dioxide were measured by the Taylor dispersion method at 308.2 K and 7.9 to 40 MPa and at 313.2 K and 8.0 to 37 MPa. The D12 values obtained from the response curves by the method of fitting in the time domain were more accurate than those obtained by the moment method. At pressures lower than about 8.3 MPa at 308.2 K or 9.1 MPa at 313.2 K, the accuracy in the D12 values was found to decrease significantly with decreasing pressure by examining (peak area) × ua,cal, the values of S10, the fitting error ε, and ua,cal/ua,exp as a function of pressure. The D12 values at pressures higher than 8.3 MPa at 308.2 K or 9.1 MPa at 313.2 K were well represented with the Schmidt number correlation. The D12 data with larger fitting errors (ε &gt
0.01) showed larger deviations from the values predicted by this correlation.

DOI： 10.1023/A:1006637401868

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記述言語：英語   出版者・発行元：Kluwer Academic/Plenum Publ Corp  

Binary diffusion coefficients of acetone in carbon dioxide were measured by the Taylor dispersion method at 308.2 K and 7.9 to 40 MPa and at 313.2 K and 8.0 to 37 MPa. The D12 values obtained from the response curves by the method of fitting in the time domain were more accurate than those obtained by the moment method. At pressures lower than about 8.3 MPa at 308.2 K or 9.1 MPa at 313.2 K, the accuracy in the D12 values was found to decrease significantly with decreasing pressure by examining (peak area) × ua,cal, the values of S10, the fitting error ε, and ua,cal/ua,exp as a function of pressure. The D12 values at pressures higher than 8.3 MPa at 308.2 K or 9.1 MPa at 313.2 K were well represented with the Schmidt number correlation. The D12 data with larger fitting errors (ε &gt
0.01) showed larger deviations from the values predicted by this correlation.

DOI： 10.1023/A:1006637401868

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記述言語：英語   出版者・発行元：SOC CHEMICAL ENG JAPAN  

This article studies the effects of various supercritical fluids on the weight losses of lignocellulosic materials with the data reported by Li and Kiran (1988). It is found that the solvent effect on the weight losses is of less importance than the thermal degradation reactions In the absence of water. In the presence of water at about 190 degrees C and 29 MPa, the reaction order is 0.5 with respect to water mole fraction.

DOI： 10.1252/jcej.33.292

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

The anomaly in binary diffusion coefficients has been reported by Nishiumi and co-workers in the near-critical region of pure CO2 solvent with the Taylor dispersion technique when the relatively large amount of solute as a tracer was injected. We have demonstrated that the mixture of the solute and CO2 solvent does not attain to the supercritical state at most axial positions of the diffusion column under their measurement conditions showing the anomaly.

DOI： 10.1021/ie990275r

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記述言語：英語   出版者・発行元：ACS  

The anomaly in binary diffusion coefficients in the near-critical region of pure CO2 solvent with the Taylor dispersion technique when the relatively large amount of solute as a tracer was injected is examined. Results show that the mixture of the solute and CO2 solvent does not attain to the supercritical state at most axial positions of the diffusion column under their measurement conditions showing the anomaly.

DOI： 10.1021/ie990275r

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記述言語：英語   出版者・発行元：ACS  

The anomaly in binary diffusion coefficients in the near-critical region of pure CO2 solvent with the Taylor dispersion technique when the relatively large amount of solute as a tracer was injected is examined. Results show that the mixture of the solute and CO2 solvent does not attain to the supercritical state at most axial positions of the diffusion column under their measurement conditions showing the anomaly.

DOI： 10.1021/ie990275r

Scopus

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記述言語：英語   出版者・発行元：ACS  

The anomaly in binary diffusion coefficients in the near-critical region of pure CO2 solvent with the Taylor dispersion technique when the relatively large amount of solute as a tracer was injected is examined. Results show that the mixture of the solute and CO2 solvent does not attain to the supercritical state at most axial positions of the diffusion column under their measurement conditions showing the anomaly.

DOI： 10.1021/ie990275r

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記述言語：英語  

The effects of additives on hydrolysis rate and glucose yield were studied with bomb-type small batch reactors in hydrolysis of cellulosic samples under pressures in the temperature range from 250°C to 380°C. Although the rates were significantly enhanced by acidic additives (H2SO4, CH3COOH), the glucose yields were not. The yields with water were higher than those with water+additives. © 2000 Elsevier B.V. All rights reserved.

DOI： 10.1016/S0921-0423(00)80033-7

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記述言語：英語   出版者・発行元：Society of Chemical Engineers, Japan  

This article studies the effects of various supercritical fluids on the weight losses of lignocellulosic materials with the data reported by Li and Kiran (1988). It is found that the solvent effect on the weight losses is of less importance than the thermal degradation reactions in the absence of water. In the presence of water at about 190°C and 29 MPa, the reaction order is 0.5 with respect to water mole fraction.

DOI： 10.1252/jcej.33.292

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記述言語：英語   出版者・発行元：Elsevier Science B.V.  

Diffusion coefficients of linoleic acid methyl ester, Vitamin K3 and indole in mixtures of carbon dioxide and n-hexane were measured at 313.2 K, and 16.0 and 25.0 MPa by using the Taylor dispersion method. It was found that the measured diffusion coefficients D(1m) were well correlated by the Blanc's equation: (D(1m) = 1 over x2/D12 + x3/D13) where x2 and x3 are mole fractions of CO2 and n-hexane, and D12 and D13 are binary diffusion coefficients of the solutes in CO2 and n-hexane, respectively, measured at the same temperature and pressure. Other equations for D(1m), as a function of temperature and solvent viscosity, were tested as a possible correlating equation.

DOI： 10.1016/S0378-3812(99)00240-X

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記述言語：英語   出版者・発行元：Elsevier Science B.V.  

Diffusion coefficients of linoleic acid methyl ester, Vitamin K3 and indole in mixtures of carbon dioxide and n-hexane were measured at 313.2 K, and 16.0 and 25.0 MPa by using the Taylor dispersion method. It was found that the measured diffusion coefficients D(1m) were well correlated by the Blanc's equation: (D(1m) = 1 over x2/D12 + x3/D13) where x2 and x3 are mole fractions of CO2 and n-hexane, and D12 and D13 are binary diffusion coefficients of the solutes in CO2 and n-hexane, respectively, measured at the same temperature and pressure. Other equations for D(1m), as a function of temperature and solvent viscosity, were tested as a possible correlating equation.

DOI： 10.1016/S0378-3812(99)00240-X

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記述言語：英語   出版者・発行元：ELSEVIER SCI LTD  

2-Aminoethanol was decomposed in sub- and supercritical water, with/without hydrogen peroxide. The conversion of total organic carbon (TOC) and the yields of ammonia and carbon dioxide were found to be enhanced under supercritical conditions of water, when compared with those under subcritical conditions. The yield of ammonia was found to be correlated with yield of carbon dioxide, nearly, irrespective of the presence of hydrogen peroxide, while conversions of 2-aminoethanol and TOC were significantly affected by adding hydrogen peroxide. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0016-2361(99)00026-5

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記述言語：英語   出版者・発行元：ELSEVIER SCI LTD  

2-Aminoethanol was decomposed in sub- and supercritical water, with/without hydrogen peroxide. The conversion of total organic carbon (TOC) and the yields of ammonia and carbon dioxide were found to be enhanced under supercritical conditions of water, when compared with those under subcritical conditions. The yield of ammonia was found to be correlated with yield of carbon dioxide, nearly, irrespective of the presence of hydrogen peroxide, while conversions of 2-aminoethanol and TOC were significantly affected by adding hydrogen peroxide. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0016-2361(99)00026-5

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Infinite dilution binary diffusion coefficients of C-5-monoalcohols in water were measured by the Taylor dispersion method at 273.2 K to 353.2 K and 0.1 MPa. At each temperature it was found that the D-12 values for the isomers increase with the boiling point of the pure alcohols. The D-12 values were correlated with temperature, water viscosity, and solute boiling point. The accuracy in the correlation was superior to the various correlations reported in the literature.

DOI： 10.1021/je9801765

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Infinite dilution binary diffusion coefficients of C-5-monoalcohols in water were measured by the Taylor dispersion method at 273.2 K to 353.2 K and 0.1 MPa. At each temperature it was found that the D-12 values for the isomers increase with the boiling point of the pure alcohols. The D-12 values were correlated with temperature, water viscosity, and solute boiling point. The accuracy in the correlation was superior to the various correlations reported in the literature.

DOI： 10.1021/je9801765

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記述言語：英語  

Effective axial dispersion coefficients Dax in packed beds were measured by the chromatographic method at 313.2 K both for supercritical CO2 in the pressure range from 11 to 35 MPa and for organic solvents at atmospheric pressure. The Dax values were correlated with the Reynolds number, Schmidt number, binary diffusivity and bed void fraction. The correlation was consistent for all solvents, irrespective of pressure. © 1998 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0896-8446(98)00049-7

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記述言語：英語  

Effective axial dispersion coefficients Dax in packed beds were measured by the chromatographic method at 313.2 K both for supercritical CO2 in the pressure range from 11 to 35 MPa and for organic solvents at atmospheric pressure. The Dax values were correlated with the Reynolds number, Schmidt number, binary diffusivity and bed void fraction. The correlation was consistent for all solvents, irrespective of pressure. © 1998 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0896-8446(98)00049-7

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記述言語：英語   出版者・発行元：ELSEVIER SCI LTD  

Dibenzyl ether was decomposed in a batch bomb-type reactor both in supercritical water at 663-688 K and water density 387 kg m(-3) and in liquid water at 553-583 K and saturated vapour pressure. The reaction pathways were assumed to consist of pyrolysis, hydrolysis and decomposition of the major products, and their rates were determined. The pyrolysis rates are substantially consistent with published data for various atmospheres. The activation energies of the pyrolysis and hydrolysis pathways are 120 and 112 kJ mol(-1) respectively. (C) 1997 Elsevier Science Ltd.

DOI： 10.1016/S0016-2361(97)00055-0

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記述言語：英語   出版者・発行元：ELSEVIER SCI LTD  

Dibenzyl ether was decomposed in a batch bomb-type reactor both in supercritical water at 663-688 K and water density 387 kg m(-3) and in liquid water at 553-583 K and saturated vapour pressure. The reaction pathways were assumed to consist of pyrolysis, hydrolysis and decomposition of the major products, and their rates were determined. The pyrolysis rates are substantially consistent with published data for various atmospheres. The activation energies of the pyrolysis and hydrolysis pathways are 120 and 112 kJ mol(-1) respectively. (C) 1997 Elsevier Science Ltd.

DOI： 10.1016/S0016-2361(97)00055-0

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DOI： 10.1252/kakoronbunshu.23.67

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Binary diffusion coefficients D-12 of benzene at infinite dilution in carbon dioxide were measured at 313.2 K in the pressure range from 8.5 to 30 MPa by the Taylor dispersion method. At 313.2 K, the measured values in this study were slightly higher than those of Swaid and Schneider, 1979, and lower than those of Sassiat et al., 1987. It was found that the D-12 values measured with the coiled diffusion column installed vertically were lower than those when it was installed horizontally. The correlation of D-12 with solvent viscosity was effective for the D-12 of benzene, both in dense CO2 and in the liquid solvents: hexane, cyclohexane and dodecane. In addition, the measured D-12 decreased smoothly with increasing pressure, and there was no evidence of the anomalous decrease in D-12 at 313.2 K in the pressure range from 8.5 to 30 MPa.

DOI： 10.1016/S0378-3812(96)03084-1

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

Binary diffusion coefficients D-12 of benzene at infinite dilution in carbon dioxide were measured at 313.2 K in the pressure range from 8.5 to 30 MPa by the Taylor dispersion method. At 313.2 K, the measured values in this study were slightly higher than those of Swaid and Schneider, 1979, and lower than those of Sassiat et al., 1987. It was found that the D-12 values measured with the coiled diffusion column installed vertically were lower than those when it was installed horizontally. The correlation of D-12 with solvent viscosity was effective for the D-12 of benzene, both in dense CO2 and in the liquid solvents: hexane, cyclohexane and dodecane. In addition, the measured D-12 decreased smoothly with increasing pressure, and there was no evidence of the anomalous decrease in D-12 at 313.2 K in the pressure range from 8.5 to 30 MPa.

DOI： 10.1016/S0378-3812(96)03084-1

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記述言語：英語   出版者・発行元：SOC CHEMICAL ENG JAPAN  

DOI： 10.1252/jcej.29.191

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記述言語：英語   出版者・発行元：化学工学協会  

DOI： 10.1252/jcej.29.191

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DOI： 10.4131/jshpreview.5.34

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DOI： 10.1252/kakoronbunshu.21.866

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記述言語：日本語   出版者・発行元：化学工学協会  

An empirical correlation given by<BR>D₁₂/T=1.013×10^-14η^-0.9222<BR>is proposed for predicting binary/pseudo binary diffusion coefficients of carbon dioxide in water and in aqueous electrolytic solutions, where D₁₂ is diffusion coefficient [m²/s], T is temperature [K], and ηis viscosity [Pa s].The average absolute deviation AAD for this correlation is 5.6% for the literature data on D₁₂ of CO₂ in water with number of data points N of 79 and 3.9% (N=103) for those in aqueous electrolytic solutions. The above correlation obtained in this study is more accurate than the various empirical correlations proposed in the literature.

DOI： 10.1252/kakoronbunshu.21.824

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00034332849?from=CiNii

DOI： 10.1252/kakoronbunshu.21.204

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Binary diffusion coefficients for infinitely dilute solutions of acetone, benzene, toluene, m-xylene, 1,3,5-trimethylbenzene, and naphthalene in hexane, in dodecane, and in cyclohexane were measured from 303.2 to 333.2 K and at 16.0 MPa using the Taylor dispersion technique. In addition, the measurements for o- and p-xylenes, vitamin K3, linoleic acid methyl ester, indole, dl-limonene, vitamin A acetate, vitamin E, and vitamin K1 in hexane and vitamin K3 and linoleic acid methyl ester in dodecane were made at the limited conditions. The D12 results in the three solvents are expressed by the equation D12/T = alphaeta(beta) with average absolute deviation of 5.2%, where eta is the solvent viscosity and alpha and beta are constants related to the solute molar volume at the normal boiling point. For the D12 measured in this study this correlation is as accurate as Nakanishi's correlation which is superior to other correlations examined.

DOI： 10.1021/je00016a062

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

Binary diffusion coefficients for infinitely dilute solutions of acetone, benzene, toluene, m-xylene, 1,3,5-trimethylbenzene, and naphthalene in hexane, in dodecane, and in cyclohexane were measured from 303.2 to 333.2 K and at 16.0 MPa using the Taylor dispersion technique. In addition, the measurements for o- and p-xylenes, vitamin K3, linoleic acid methyl ester, indole, dl-limonene, vitamin A acetate, vitamin E, and vitamin K1 in hexane and vitamin K3 and linoleic acid methyl ester in dodecane were made at the limited conditions. The D12 results in the three solvents are expressed by the equation D12/T = alphaeta(beta) with average absolute deviation of 5.2%, where eta is the solvent viscosity and alpha and beta are constants related to the solute molar volume at the normal boiling point. For the D12 measured in this study this correlation is as accurate as Nakanishi's correlation which is superior to other correlations examined.

DOI： 10.1021/je00016a062

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DOI： 10.1252/kakoronbunshu.20.579

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DOI： 10.1252/kakoronbunshu.19.1157

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DOI： 10.1252/kakoronbunshu.19.544

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記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）   出版者・発行元：化学工学会  

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記述言語：英語   出版者・発行元：Inst. Sugar Ind.  

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DOI： 10.1252/kakoronbunshu.19.245

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記述言語：英語   出版者・発行元：AMER INST CHEMICAL ENGINEERS  

Binary diffusion coefficients of some organic compounds in carbon dioxide at 313.2 K and 16.0/25.0 MPa were measured by using the Taylor-Aris tracer response technique. We propose a new correlation of Schmidt numbers as a function of solvent molar volumes for predicting binary diffusion coefficients in dense CO2 and self-diffusion coefficients of dense CO2. The correlation was also found to be valid for predicting self-diffusion coefficients of dense CH4 at F(v)/A*&lt;40 or v2/(v2)0&gt;1.62.

DOI： 10.1002/aic.690381109

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記述言語：英語   出版者・発行元：AMER INST CHEMICAL ENGINEERS  

Binary diffusion coefficients of some organic compounds in carbon dioxide at 313.2 K and 16.0/25.0 MPa were measured by using the Taylor-Aris tracer response technique. We propose a new correlation of Schmidt numbers as a function of solvent molar volumes for predicting binary diffusion coefficients in dense CO2 and self-diffusion coefficients of dense CO2. The correlation was also found to be valid for predicting self-diffusion coefficients of dense CH4 at F(v)/A*&lt;40 or v2/(v2)0&gt;1.62.

DOI： 10.1002/aic.690381109

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DOI： 10.1252/kakoronbunshu.18.769

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DOI： 10.1252/kakoronbunshu.18.375

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記述言語：英語   出版者・発行元：BUTTERWORTH-HEINEMANN LTD  

Vinasse, residue from the ethanol distillation of alcohol-fermented sugar-cane juice, was treated with high-density water at temperatures from 200 to 500-degrees-C. The products were separated into ether soluble, ether/water insoluble and aqueous fractions, and char. The ether soluble and ether/water insoluble fractions were referred to as oil. At 350-degrees-C, for example, 15.8 wt% of dried vinasse turned into oil. The gaseous products were found to consist of mainly CO2 with a small amount of CO and CH4.

DOI： 10.1016/0016-2361(92)90075-Y

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記述言語：英語   出版者・発行元：BUTTERWORTH-HEINEMANN LTD  

Vinasse, residue from the ethanol distillation of alcohol-fermented sugar-cane juice, was treated with high-density water at temperatures from 200 to 500-degrees-C. The products were separated into ether soluble, ether/water insoluble and aqueous fractions, and char. The ether soluble and ether/water insoluble fractions were referred to as oil. At 350-degrees-C, for example, 15.8 wt% of dried vinasse turned into oil. The gaseous products were found to consist of mainly CO2 with a small amount of CO and CH4.

DOI： 10.1016/0016-2361(92)90075-Y

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DOI： 10.1252/kakoronbunshu.17.1229

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記述言語：英語  

Binary diffusion coefficients were measured for C16-C24 unsaturated fatty acid methyl esters in supercritical carbon dioxide (at 313 K and 16.0 MPa) and linoleic acid methyl ester in supercritical carbon dioxide (at 308-328 K and 14.0-33.6 MPa). We propose an empirical equation that correlates the diffusion coefficients in terms of Schmidt numbers, (Sc - Sc*)/Sc*, with molar volumes, (v2 - (v2)0) / (v2)0 where Sc and Sc* are Schmidt numbers at the prescribed pressure and at atmospheric pressure, respectively, and where v2 and (v2)0 are molar volumes at the prescribed pressure and at which viscous flow ceases, respectively. Also, it was found that CO2 self-diffusion coefficient values recommended by Chen (1983) were well correlated by this equation. © 1991, American Chemical Society. All rights reserved.

DOI： 10.1021/ie00054a038

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記述言語：英語  

Binary diffusion coefficients were measured for C16-C24 unsaturated fatty acid methyl esters in supercritical carbon dioxide (at 313 K and 16.0 MPa) and linoleic acid methyl ester in supercritical carbon dioxide (at 308-328 K and 14.0-33.6 MPa). We propose an empirical equation that correlates the diffusion coefficients in terms of Schmidt numbers, (Sc - Sc*)/Sc*, with molar volumes, (v2 - (v2)0) / (v2)0 where Sc and Sc* are Schmidt numbers at the prescribed pressure and at atmospheric pressure, respectively, and where v2 and (v2)0 are molar volumes at the prescribed pressure and at which viscous flow ceases, respectively. Also, it was found that CO2 self-diffusion coefficient values recommended by Chen (1983) were well correlated by this equation. © 1991, American Chemical Society. All rights reserved.

DOI： 10.1021/ie00054a038

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DOI： 10.1252/jcej.24.397

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DOI： 10.1252/jcej.24.387

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DOI： 10.1252/jcej.24.397

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DOI： 10.1252/jcej.24.387

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記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：BUTTERWORTH-HEINEMANN LTD  

DOI： 10.1016/0016-2361(90)90298-5

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記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：BUTTERWORTH-HEINEMANN LTD  

DOI： 10.1016/0016-2361(90)90298-5

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DOI： 10.1016/0016-2361(90)90099-C

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DOI： 10.1016/0016-2361(90)90099-C

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記述言語：日本語   出版者・発行元：水道協会  

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DOI： 10.1252/jcej.22.527

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DOI： 10.1252/jcej.22.527

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記述言語：英語   出版者・発行元：Elsevier Sci. Pub.  

DOI： 10.1016/0165-2370(89)85005-3

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DOI： 10.1016/0165-2370(89)85005-3

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

DOI： 10.1021/ac00177a008

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

DOI： 10.1021/ac00177a008

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記述言語：英語   出版者・発行元：BUTTERWORTH-HEINEMANN LTD  

DOI： 10.1016/0016-2361(88)90068-3

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記述言語：英語   出版者・発行元：BUTTERWORTH-HEINEMANN LTD  

DOI： 10.1016/0016-2361(88)90068-3

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記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：BUTTERWORTH-HEINEMANN LTD  

DOI： 10.1016/0016-2361(88)90168-8

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記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：BUTTERWORTH-HEINEMANN LTD  

DOI： 10.1016/0016-2361(88)90168-8

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記述言語：英語   出版者・発行元：Elsevier Sci. Pub.  

DOI： 10.1016/0165-2370(88)80051-2

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DOI： 10.1016/0165-2370(88)80051-2

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記述言語：英語   出版者・発行元：BUTTERWORTH-HEINEMANN LTD  

DOI： 10.1016/0016-2361(88)90004-X

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記述言語：英語   出版者・発行元：BUTTERWORTH-HEINEMANN LTD  

DOI： 10.1016/0016-2361(88)90004-X

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DOI： 10.1252/kakoronbunshu.15.191

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記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

DOI： 10.1016/0009-2509(88)85165-0

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記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

DOI： 10.1016/0009-2509(88)85165-0

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記述言語：英語   出版者・発行元：Elsevier Sci. Pub.  

DOI： 10.1016/0165-2370(87)80005-0

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DOI： 10.1016/0165-2370(87)80005-0

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DOI： 10.1252/jcej.20.23

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DOI： 10.1252/jcej.20.23

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DOI： 10.1016/0165-2370(86)85004-5

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記述言語：英語   出版者・発行元：Elsevier Sci. Pub.  

DOI： 10.1016/0165-2370(86)85004-5

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記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）   出版者・発行元：化学工業協会  

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記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）   出版者・発行元：化学工業協会  

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記述言語：英語  

The weight loss and the product yields from cellulose powder, cellulose particles, and filter paper were measured simultaneously under flash pyrolysis conditions. Products can be grouped into two distinct types. One is a CO behavior for which yields Increase with the weight loss and at weight loss above 40% also become a function of pyrolysis temperature. The second is a CO2 behavior for which yields are proportional to the weight loss and independent of pyrolysis temperature. Yields of both the CO behavior and CO2 behavior products correlate linearly in log-log plots with the CO yields and with CO2yields, respectively. Because CO yields correlate well with the weight loss and pyrolysis temperature, major gaseous and liquid products obtained from flash pyrolysis of cellulose powder or particles can be predicted accurately. Variables such as heating rate, particle size, and pyrolysis temperature do not affect the relationships. © 1986, American Chemical Society. All rights reserved.

DOI： 10.1021/i200032a027

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記述言語：英語  

The weight loss and the product yields from cellulose powder, cellulose particles, and filter paper were measured simultaneously under flash pyrolysis conditions. Products can be grouped into two distinct types. One is a CO behavior for which yields Increase with the weight loss and at weight loss above 40% also become a function of pyrolysis temperature. The second is a CO2 behavior for which yields are proportional to the weight loss and independent of pyrolysis temperature. Yields of both the CO behavior and CO2 behavior products correlate linearly in log-log plots with the CO yields and with CO2yields, respectively. Because CO yields correlate well with the weight loss and pyrolysis temperature, major gaseous and liquid products obtained from flash pyrolysis of cellulose powder or particles can be predicted accurately. Variables such as heating rate, particle size, and pyrolysis temperature do not affect the relationships. © 1986, American Chemical Society. All rights reserved.

DOI： 10.1021/i200032a027

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DOI： 10.1252/jcej.18.455

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記述言語：英語   出版者・発行元：SOC CHEMICAL ENG JAPAN  

DOI： 10.1252/jcej.18.455

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記述言語：英語   出版者・発行元：Inst. Gas Technol  

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記述言語：英語   出版者・発行元：Pergamon Press Ltd.  

DOI： 10.1016/0009-2509(79)85064-2

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DOI： 10.1016/0009-2509(79)85064-2

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記述言語：英語   出版者・発行元：Pergamon Press Ltd.  

DOI： 10.1016/0009-2509(78)85120-3

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DOI： 10.1016/0009-2509(78)85120-3

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