The Experts below are selected from a list of 31674 Experts worldwide ranked by ideXlab platform
Osamu Yamamuro - One of the best experts on this subject based on the ideXlab platform.
-
hydration of alcohol clusters in 1 propanol water mixture studied by quasielastic neutron scattering and an interpretation of anomalous excess partial molar volume
Journal of Chemical Physics, 2006Co-Authors: Masakatsu Misawa, D Hosaka, Yasuhiro Inamura, Osamu YamamuroAbstract:Quasielastic neutron scattering measurements have been made for 1-Propanol-water mixtures in a range of alcohol concentration from 0.0 to 0.167 in mole fraction at 25°C. Fraction α of water molecules hydrated to fractal surface of alcohol clusters in 1-Propanol-water mixture was obtained as a function of alcohol concentration. Average hydration number Nws of 1-Propanol molecule is derived from the value of α as a function of alcohol concentration. By extrapolating Nws to infinite dilution, we obtain values of 12–13 as hydration number of isolated 1-Propanol molecule. A simple interpretation of structural origin of anomalous excess partial molar volume of water is proposed and as a result a simple equation for the excess partial molar volume is deduced in terms of α. Calculated values of the excess partial molar volumes of water and 1-Propanol and the excess molar volume of the mixture are in good agreement with experimental values.
-
hydration of alcohol clusters in 1 propanol water mixture studied by quasielastic neutron scattering and an interpretation of anomalous excess partial molar volume
Journal of Chemical Physics, 2006Co-Authors: Masakatsu Misawa, D Hosaka, Yasuhiro Inamura, Osamu YamamuroAbstract:Quasielastic neutron scattering measurements have been made for 1-Propanol-water mixtures in a range of alcohol concentration from 0.0 to 0.167 in mole fraction at 25 degrees C. Fraction alpha of water molecules hydrated to fractal surface of alcohol clusters in 1-Propanol-water mixture was obtained as a function of alcohol concentration. Average hydration number N(ws) of 1-Propanol molecule is derived from the value of alpha as a function of alcohol concentration. By extrapolating N(ws) to infinite dilution, we obtain values of 12-13 as hydration number of isolated 1-Propanol molecule. A simple interpretation of structural origin of anomalous excess partial molar volume of water is proposed and as a result a simple equation for the excess partial molar volume is deduced in terms of alpha. Calculated values of the excess partial molar volumes of water and 1-Propanol and the excess molar volume of the mixture are in good agreement with experimental values.
Gerd Maurer - One of the best experts on this subject based on the ideXlab platform.
-
quantitative nmr spectroscopy of binary liquid mixtures aldehyde alcohol part iii 1 decanal or 3 phenylpropanal or 2 chlorobenzaldehyde methanol or ethanol or 1 propanol
The Journal of Chemical Thermodynamics, 2014Co-Authors: Silke Jaubert, Gerd MaurerAbstract:Abstract The thermodynamic properties of binary liquid mixtures of (aldehyde + alcohol) are strongly influenced by chemical reactions in particular around and below ambient temperature. In two previous publications the chemical reaction equilibrium was investigated by 13C – Fourier transform NMR-spectroscopy at temperatures between 255 K and 295 K for a series of aldehydes (acetaldehyde, 1-propanal, 1-butanal, 1-heptanal) with three alcohols (methanol, ethanol, 1-Propanol). Here these investigations are extended to three more aldehydes (1-decanal, 3-phenylpropanal and 2-chlorobenzaldehyde, respectively). The results for the binary systems with decanal or 3-phenylpropanal as the aldehyde in the binary mixture (aldehyde + alcohol) confirm the expectations from the first parts of this series, i.e., that the majority of the constituents of the mixture is present as hemiacetal and the first two poly(oxymethylene) – hemiacetals. The numerical results for the chemical reaction equilibrium constants from the previous investigations can be used to predict quantitatively the speciation in binary systems of ((either 1-decanal or 3-phenylpropanal) + (either methanol or ethanol or 1-Propanol)). However the experimental results with 2-chlorobenzaldehyde reveal a different behaviour. In all investigated systems (2-chlorobenzaldehyde + alcohol) the most important reaction product was the corresponding acetal whereas the amounts of hemiacetal were very small. While the amounts of hemiacteal could still be quantified, it was not possible to quantify the amount of any poly(oxymethylene) – hemiacetal.
-
reprint of quantitative nmr spectroscopy of binary liquid mixtures aldehyde alcohol part ii propanal or butanal or heptanal methanol or ethanol or 1 propanol
The Journal of Chemical Thermodynamics, 2013Co-Authors: Silke Jaubert, Gerd MaurerAbstract:Abstract The chemical reactions of aldehydes with alcohols to (hemiacetals and poly(oxymethylene) hemiacetals) have an essential influence on the thermodynamic properties and related phenomena like, for example, the vapor + liquid phase equilibrium of such liquid mixtures. This is well known in the literature for systems such as, for example, formaldehyde and methanol. Experimental information on the chemical reaction equilibria in mixtures with aldehydes other than formaldehyde and alcohols is extremely scarce. Therefore, in the first part of this series, quantitative NMR spectroscopy was used to investigate the chemical reaction equilibrium in binary liquid mixtures of acetaldehyde and an alcohol (methanol or ethanol or 1-Propanol) at temperatures between (255 and 295) K. That work is here extended to three other aldehydes, viz. (1-propanal, 1-butanal and 1-heptanal). The results confirm the expectations from the first part of this series, i.e., that the majority of the constituents of the mixture is present as hemiacetal and the first two poly(oxymethylene) hemiacetals. For example, in an equimolar liquid mixture of {1-heptanal + methanol (or + ethanol or + 1-Propanol)} at T = 273 K about 88% (or 81% for both other alcohols) of the aldehyde is bound to hemiacetal and the first two poly(oxymethylene) hemiacetals, i.e., the conversion rates are nearly the same as in the previous investigations with acetaldehyde instead of 1-heptanal. In the series investigated of combinations of aldehydes and alcohols, the particular aldehyde has only a small influence on the conversion rate. In the series of alcohols investigated only methanol has a somewhat larger influence whereas the results (speciation and conversion) for ethanol and 1-Propanol are very similar. The NMR-spectroscopic results were also evaluated to determine the mole-fraction based chemical reaction equilibrium constants for the formation of the hemiacetals and the first two poly(oxymethylene) hemiacetals and the chemical reaction enthalpies.
Masakatsu Misawa - One of the best experts on this subject based on the ideXlab platform.
-
hydration of alcohol clusters in 1 propanol water mixture studied by quasielastic neutron scattering and an interpretation of anomalous excess partial molar volume
Journal of Chemical Physics, 2006Co-Authors: Masakatsu Misawa, D Hosaka, Yasuhiro Inamura, Osamu YamamuroAbstract:Quasielastic neutron scattering measurements have been made for 1-Propanol-water mixtures in a range of alcohol concentration from 0.0 to 0.167 in mole fraction at 25°C. Fraction α of water molecules hydrated to fractal surface of alcohol clusters in 1-Propanol-water mixture was obtained as a function of alcohol concentration. Average hydration number Nws of 1-Propanol molecule is derived from the value of α as a function of alcohol concentration. By extrapolating Nws to infinite dilution, we obtain values of 12–13 as hydration number of isolated 1-Propanol molecule. A simple interpretation of structural origin of anomalous excess partial molar volume of water is proposed and as a result a simple equation for the excess partial molar volume is deduced in terms of α. Calculated values of the excess partial molar volumes of water and 1-Propanol and the excess molar volume of the mixture are in good agreement with experimental values.
-
hydration of alcohol clusters in 1 propanol water mixture studied by quasielastic neutron scattering and an interpretation of anomalous excess partial molar volume
Journal of Chemical Physics, 2006Co-Authors: Masakatsu Misawa, D Hosaka, Yasuhiro Inamura, Osamu YamamuroAbstract:Quasielastic neutron scattering measurements have been made for 1-Propanol-water mixtures in a range of alcohol concentration from 0.0 to 0.167 in mole fraction at 25 degrees C. Fraction alpha of water molecules hydrated to fractal surface of alcohol clusters in 1-Propanol-water mixture was obtained as a function of alcohol concentration. Average hydration number N(ws) of 1-Propanol molecule is derived from the value of alpha as a function of alcohol concentration. By extrapolating N(ws) to infinite dilution, we obtain values of 12-13 as hydration number of isolated 1-Propanol molecule. A simple interpretation of structural origin of anomalous excess partial molar volume of water is proposed and as a result a simple equation for the excess partial molar volume is deduced in terms of alpha. Calculated values of the excess partial molar volumes of water and 1-Propanol and the excess molar volume of the mixture are in good agreement with experimental values.
Silke Jaubert - One of the best experts on this subject based on the ideXlab platform.
-
quantitative nmr spectroscopy of binary liquid mixtures aldehyde alcohol part iii 1 decanal or 3 phenylpropanal or 2 chlorobenzaldehyde methanol or ethanol or 1 propanol
The Journal of Chemical Thermodynamics, 2014Co-Authors: Silke Jaubert, Gerd MaurerAbstract:Abstract The thermodynamic properties of binary liquid mixtures of (aldehyde + alcohol) are strongly influenced by chemical reactions in particular around and below ambient temperature. In two previous publications the chemical reaction equilibrium was investigated by 13C – Fourier transform NMR-spectroscopy at temperatures between 255 K and 295 K for a series of aldehydes (acetaldehyde, 1-propanal, 1-butanal, 1-heptanal) with three alcohols (methanol, ethanol, 1-Propanol). Here these investigations are extended to three more aldehydes (1-decanal, 3-phenylpropanal and 2-chlorobenzaldehyde, respectively). The results for the binary systems with decanal or 3-phenylpropanal as the aldehyde in the binary mixture (aldehyde + alcohol) confirm the expectations from the first parts of this series, i.e., that the majority of the constituents of the mixture is present as hemiacetal and the first two poly(oxymethylene) – hemiacetals. The numerical results for the chemical reaction equilibrium constants from the previous investigations can be used to predict quantitatively the speciation in binary systems of ((either 1-decanal or 3-phenylpropanal) + (either methanol or ethanol or 1-Propanol)). However the experimental results with 2-chlorobenzaldehyde reveal a different behaviour. In all investigated systems (2-chlorobenzaldehyde + alcohol) the most important reaction product was the corresponding acetal whereas the amounts of hemiacetal were very small. While the amounts of hemiacteal could still be quantified, it was not possible to quantify the amount of any poly(oxymethylene) – hemiacetal.
-
reprint of quantitative nmr spectroscopy of binary liquid mixtures aldehyde alcohol part ii propanal or butanal or heptanal methanol or ethanol or 1 propanol
The Journal of Chemical Thermodynamics, 2013Co-Authors: Silke Jaubert, Gerd MaurerAbstract:Abstract The chemical reactions of aldehydes with alcohols to (hemiacetals and poly(oxymethylene) hemiacetals) have an essential influence on the thermodynamic properties and related phenomena like, for example, the vapor + liquid phase equilibrium of such liquid mixtures. This is well known in the literature for systems such as, for example, formaldehyde and methanol. Experimental information on the chemical reaction equilibria in mixtures with aldehydes other than formaldehyde and alcohols is extremely scarce. Therefore, in the first part of this series, quantitative NMR spectroscopy was used to investigate the chemical reaction equilibrium in binary liquid mixtures of acetaldehyde and an alcohol (methanol or ethanol or 1-Propanol) at temperatures between (255 and 295) K. That work is here extended to three other aldehydes, viz. (1-propanal, 1-butanal and 1-heptanal). The results confirm the expectations from the first part of this series, i.e., that the majority of the constituents of the mixture is present as hemiacetal and the first two poly(oxymethylene) hemiacetals. For example, in an equimolar liquid mixture of {1-heptanal + methanol (or + ethanol or + 1-Propanol)} at T = 273 K about 88% (or 81% for both other alcohols) of the aldehyde is bound to hemiacetal and the first two poly(oxymethylene) hemiacetals, i.e., the conversion rates are nearly the same as in the previous investigations with acetaldehyde instead of 1-heptanal. In the series investigated of combinations of aldehydes and alcohols, the particular aldehyde has only a small influence on the conversion rate. In the series of alcohols investigated only methanol has a somewhat larger influence whereas the results (speciation and conversion) for ethanol and 1-Propanol are very similar. The NMR-spectroscopic results were also evaluated to determine the mole-fraction based chemical reaction equilibrium constants for the formation of the hemiacetals and the first two poly(oxymethylene) hemiacetals and the chemical reaction enthalpies.
D Hosaka - One of the best experts on this subject based on the ideXlab platform.
-
hydration of alcohol clusters in 1 propanol water mixture studied by quasielastic neutron scattering and an interpretation of anomalous excess partial molar volume
Journal of Chemical Physics, 2006Co-Authors: Masakatsu Misawa, D Hosaka, Yasuhiro Inamura, Osamu YamamuroAbstract:Quasielastic neutron scattering measurements have been made for 1-Propanol-water mixtures in a range of alcohol concentration from 0.0 to 0.167 in mole fraction at 25°C. Fraction α of water molecules hydrated to fractal surface of alcohol clusters in 1-Propanol-water mixture was obtained as a function of alcohol concentration. Average hydration number Nws of 1-Propanol molecule is derived from the value of α as a function of alcohol concentration. By extrapolating Nws to infinite dilution, we obtain values of 12–13 as hydration number of isolated 1-Propanol molecule. A simple interpretation of structural origin of anomalous excess partial molar volume of water is proposed and as a result a simple equation for the excess partial molar volume is deduced in terms of α. Calculated values of the excess partial molar volumes of water and 1-Propanol and the excess molar volume of the mixture are in good agreement with experimental values.
-
hydration of alcohol clusters in 1 propanol water mixture studied by quasielastic neutron scattering and an interpretation of anomalous excess partial molar volume
Journal of Chemical Physics, 2006Co-Authors: Masakatsu Misawa, D Hosaka, Yasuhiro Inamura, Osamu YamamuroAbstract:Quasielastic neutron scattering measurements have been made for 1-Propanol-water mixtures in a range of alcohol concentration from 0.0 to 0.167 in mole fraction at 25 degrees C. Fraction alpha of water molecules hydrated to fractal surface of alcohol clusters in 1-Propanol-water mixture was obtained as a function of alcohol concentration. Average hydration number N(ws) of 1-Propanol molecule is derived from the value of alpha as a function of alcohol concentration. By extrapolating N(ws) to infinite dilution, we obtain values of 12-13 as hydration number of isolated 1-Propanol molecule. A simple interpretation of structural origin of anomalous excess partial molar volume of water is proposed and as a result a simple equation for the excess partial molar volume is deduced in terms of alpha. Calculated values of the excess partial molar volumes of water and 1-Propanol and the excess molar volume of the mixture are in good agreement with experimental values.
