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1.
Parimal C. Dey Muhammad A. Motin Tapan K. Biswas Entazul M. Huque 《Monatshefte für Chemie / Chemical Monthly》2003,37(2):797-809
The apparent molar volume (φv) and viscosity (η) of L(+)-arabinose, D(+)-galactose, D(−)-fructose, D(+)-glucose, sucrose, lactose, and maltose in water and in 0.1% and 0.3% water-Surf Excel solutions were measured as a function of solute concentrations at 308.15, 313.15, and 323.15 K, respectively. The apparent molar volume (φv) of the carbohydrates was found to be a linear function of the concentration. From a φv versus molality (b) plot, the apparent molar volume at infinite dilution (), which is practically equal to the partial molar volume at infinite dilutions () of these substances was determined. The viscosity coefficients B and D for the carbohydrates were calculated on the basis of the viscosity of the solutions and the solvent using the Jones-Dole equation. The activation free energy for viscous flow (ΔG ≠) of the solutions was also calculated using the Eyring equation. The carbohydrates showed structure making behaviour both in water and in water-Surf Excel solutions. When water-Surf Excel solutions and pure water solutions containing carbohydrate molecules are compared, the former were found to be more structured. The behaviour of these solutes in water and in water-Surf Excel solution systems is discussed in the light of solute–solvent interactions. 相似文献
2.
Dulal Chandra Kabiraz Tapan Kumar Biswas M. Entazul Huque 《Monatshefte für Chemie / Chemical Monthly》2010,39(11):1063-1068
Abstract
The apparent molar volumes (φ v) of KCl, KNO3, MgCl2, and Mg(NO3)2 have been determined in water and in aqueous sodium dodecylsulfate solutions from density measurements at 303.15, 308.15, 313.15, 318.15, and 323.15 K. The limiting apparent molar volumes (jv0 \varphi_{v}^{0} ) and experimental slopes (S v) were derived from the Masson equation. The partial molar volume transfer (\Updelta [`(V)]\texttr ) (\Updelta {\bar{V}}_{\text{tr}} ) of the electrolytes were obtained from limiting apparent molar volume data from water to aqueous sodium dodecylsulfate solutions and have been interpreted in terms of ion–ion, hydrophilic–hydrophilic, and hydrophobic–hydrophobic interactions on the basis of a co-sphere overlap model. It is shown that the transfer volumes (\Updelta [`(V)]\texttr ) (\Updelta {\bar{V}}_{\text{tr}} ) are positive and increase with increasing sodium dodecylsulfate concentration for all electrolytes. The structure making or breaking capacities of the electrolytes have been inferred from the sign of [∂2 φ v0/∂T 2]p, i.e., the second derivative of the limiting apparent molar volume with respect to temperature at constant pressure. In water, KCl and KNO3 exhibit structure breaking and MgCl2 and Mg(NO3)2 exhibit structure making behavior. All the studied electrolytes were found to act as structure makers in aqueous sodium dodecylsulfate solutions. 相似文献3.
Parimal C. Dey Muhammad A. Motin Tapan K. Biswas Entazul M. Huque 《Monatshefte für Chemie / Chemical Monthly》2003,134(6):797-809
Summary. The apparent molar volume (φv) and viscosity (η) of L(+)-arabinose, D(+)-galactose, D(−)-fructose, D(+)-glucose, sucrose, lactose, and maltose in water and in 0.1% and 0.3% water-Surf Excel solutions were measured as a function
of solute concentrations at 308.15, 313.15, and 323.15 K, respectively. The apparent molar volume (φv) of the carbohydrates was found to be a linear function of the concentration. From a φv versus molality (b) plot, the apparent molar volume at infinite dilution (), which is practically equal to the partial molar volume at infinite dilutions () of these substances was determined. The viscosity coefficients B and D for the carbohydrates were calculated on the basis of the viscosity of the solutions and the solvent using the Jones-Dole equation. The activation free energy for viscous flow (ΔG
≠) of the solutions was also calculated using the Eyring equation. The carbohydrates showed structure making behaviour both in water and in water-Surf Excel solutions. When water-Surf
Excel solutions and pure water solutions containing carbohydrate molecules are compared, the former were found to be more
structured. The behaviour of these solutes in water and in water-Surf Excel solution systems is discussed in the light of
solute–solvent interactions.
Corresponding author. E-mail: chemistry_ru@yahoo.com
Received March 19, 2002; accepted (revised) July 31, 2002
Published online February 24, 2003 相似文献
4.
The apparent molar volumes V
2,φ
, apparent molar isentropic compressibilities K
S,2,φ
, and enthalpies of dilution of aqueous glycine, alanine, α-amino butyric acid, valine, and leucine have been determined in aqueous 1.0 and 2.0 mol⋅dm−3 sorbitol solutions at 298.15 K. These data have been used to calculate the infinite dilution standard partial molar volumes
V2,m0V_{2,m}^{0}, partial molar isentropic compressibilities KS,2,m0K_{S,2,m}^{0}, and enthalpies of dilution Δdil
H
0 of the amino acids in aqueous sorbitol, along with the standard partial molar quantities of transfer of the amino acids from
water to aqueous sorbitol. The linear correlation of V2,m0V_{2,m}^{0} for this homologous series of amino acids has been utilized to calculate the contribution to V20V_{2}^{0} of the charged end groups (NH3+\mathrm{NH}_{3}^{+}, COO−), the CH2 group, and other alkyl chains of the amino acids. The results for the standard partial molar volumes of transfer, compressibilites
and enthalpies of dilution from water to aqueous sorbitol solutions have been correlated and interpreted in terms of ion–polar,
ion–hydrophobic, and hydrophobic–hydrophobic group interactions. A comparison of these thermodynamic properties of transfer
suggest that an enhancement of the hydrophilic/polar group interactions is operating in ternary systems of amino acid, sorbitol,
and water. 相似文献
5.
Harsh Kumar Mandeep Kaur Rekha Gaba Kirtanjot Kaur 《Journal of Thermal Analysis and Calorimetry》2011,105(3):1071-1080
Densities and speeds of sound of the cyclopentane with 2-propanol, 1-butanol and 2-butanol are measured over the whole composition
range at different temperatures in the range 288.15–308.15 K and atmospheric pressure using Anton Paar DSA 5000 densimeter.
The experimental densities and speeds of sound have been used to calculate excess molar volumes, excess molar isentropic compressibilities
and excess intermolecular free length. The partial molar volumes and apparent molar volumes at infinite dilution have also
been calculated. The mixing quantities like (∂V
mE/∂T)P and (∂H
mE/∂P)T have been calculated at T = 298.15 K and these values are compared with the values calculated from Flory’s theory at equimolar composition. 相似文献
6.
Kelei Zhuo Qiufen Zhang Xiaopeng Xuan Hucheng Zhang Jianji Wang 《Frontiers of Chemistry in China》2007,2(2):193-198
Densities have been measured for Glucose + HCl +Water at 10-degree intervals from 278.15 to 318.15 K. The apparent molar volumes
(V
Φ,G) and standard partial molar volumes (V
Φ,G
0
) for Glucose in aqueous solution of 0.2, 0.4, 0.7, 1.1, 1.6, 2.1 mol·kg−1 HCl have been calculated as well as volumetric interaction parameters (V
EG) for Glucose — HCl in water and standard partial molar expansion coefficients (∂V
Φ,G
0
/ ∂T)p. Results show that (1) the apparent molar volume for Glucose in aqueous HCl solutions increases lineally with increasing
molality of Glucose and HCl; (2) V
Φ,G/0 for Glucose in aqueous HCl solutions increases lineally with increasing molality of HCl; (3) the volumetric interaction parameters
for Glucose — HCl pair in water are small positive and vary slightly with temperature; (4) the relation between V
Φ,G
0
and temperature exists as V
Φ,G
0
= a
0 + a
1(T − 273.15 K)2/3; (5) values of (∂V
Φ,G
0
/ ∂T)p are positive and increase as temperatures rise, and at given temperatures decrease slightly with increasing molalities of
HCl, indicating that the hydration of glucose decreases with increasing temperature and molality of HCl. These phenomena are
interpreted successfully by the structure interaction model.
Translated from Acta Chimica Sinica, 2006, 64(16): 1635–1641 (in Chinese) 相似文献
7.
The apparent molar volumes (V
φ
) of glycine, L-alanine and L-serine in aqueous 0 to 4 mol⋅kg−1 N-methylacetamide (NMA) solutions have been obtained by density measurement at 298.15 K. The standard partial molar volumes
(Vf0)V_{\phi}^{0}) and standard partial molar volumes of transfer (DtrVf0)\Delta_{\mathrm{tr}}V_{\phi}^{0}) have been determined for these amino acids. It has been show that hydrophilic-hydrophilic interactions between the charged
groups of the amino acids and the –CONH– group of NMA predominate for glycine and L-serine, but for L-alanine the interactions
between its side group (–CH3) and NMA predominate. The –CH3 group of L-alanine has much more influence on the value of DtrVf0\Delta_{\mathrm{tr}}V_{\phi}^{0} than that of the –OH group of L-serine. The results have been interpreted in terms of a co-sphere overlap model. 相似文献
8.
The densities and viscosities of aqueous solution of cetyltrimethylammonium bromide (0.01 mol kg−1) (CTAB) and solutions of CTAB containing amino acids, viz., glycine, l-serine, and l-valine (0.01–0.05 mol kg−1), were determined in the temperature range 298.15—313.15 K. Apparent molar volumes of the amino acids were calculated from
the density and viscosity values. The calculated apparent molar volumes were used to calculate standard partial molar volumes
(-V
20) and standard partial molar volumes of transfer of amino acids from water to an aqueous solution of CTAB. The viscosity values
were used for the calculation of the viscosity coefficients A and B in the Jones—Dole equation. The linear dependences of -V
20 and B on the number of carbon atoms in the alkyl chains of the amino acids were found. The results obtained were used in analysis
of hydrophilic-hydrophilic, hydrophilic-hydrophobic, and hydrophobic-hydrophobic interactions that occur during dissolution
of amino acids in an aqueous solution of CTAB. 相似文献
9.
P. V. Verdes M. M. Mato J. L. Legido E. Jiménez M. I. Paz Andrade 《Journal of Thermal Analysis and Calorimetry》2007,88(2):613-616
Excess molar enthalpies
of the ternary system {x
1
p-xylene+x
2decane+(1–x
1–x
2)diethyl
carbonate} and the involved binary mixtures {p-xylene+(1–x)decane}, {xp-xylene+(1–x)diethyl carbonate} and {xdecane+(1–x)diethyl carbonate} have been determined at the
temperature of 298.15 K and atmospheric pressure, over the whole composition
range, using a Calvet microcalorimeter. The experimental excess molar enthalpies H
m
E
are positive for all the binary systems studied over the whole composition
range. Excess molar enthalpy for the ternary system is positive as well, showing
maximum values at x
1=0, x
2=0.4920, x
3=0.5080, H
m,123
E=1524
J mol–1. 相似文献
10.
Density of the water-ethylene glycol binary mixtures was measured in the entire range of compositions in the temperature range
278–333.15 K (6 values) at atmospheric pressure using a vibration densimeter. Mixtures with low concentrations of ethylene
glycol were studied at 15 temperatures in the range of 274–333.15 K. Excess molar volumes V
m
E
, the partial molar volumes of water -V
1 and ethylene glycol, -V
2, the coefficients of thermal volume expansion α of the mixture, the partial molar volume coefficients of thermal expansion
of water $
\bar V_1
$
\bar V_1
and ethylene $
\bar V_2
$
\bar V_2
were calculated. Excess molar volumes were described using the Redlich-Kister equation. The density ρ of the mixture was
found to increase with the increasing ethylene glycol concentration at all temperatures, but at low content of ethylene glycol
the dependence ρ = f(T) of the mixture at ∼276.5 K passed through a maximum. The coefficient α increases sharply in the composition range 0 <
x < 0.2, in the range 0.5 < x <1 remains almost unchanged, and at T > 277 K is positive for all compositions. The dependences $
\bar \alpha _1
$
\bar \alpha _1
= f (x) and $
\bar \alpha _2
$
\bar \alpha _2
= f (x) are complex in whole temperature range and are characterized by the presence of an extremum. V
m
E
values are negative at all temperatures, and upon increase in the temperature the deviation from ideality decreases (x is the mole fraction of ethylene glycol). 相似文献
11.
Anthony Blanchard Flavien Melis Fabrice Gouanvé Jean-Matthieu Brouillat Eliane Espuche 《Journal of polymer science. Part A, Polymer chemistry》2021,59(1):70-83
The influences of the molar mass (low, medium, and high) and content of poly(vinyl alcohol) (PVOH) dispersed by melt-blending in an ethylene vinyl alcohol (EVOH) copolymer on the morphology, microstructure, thermal, mechanical, and oxygen barrier properties were investigated. Multilayer films with external low-density polyethylene layers and inner EVOH/PVOH blend layer and respective monolayer films were elaborated and characterized. EVOH/PVOH blends exhibited a good compatibility because of the initial presence of PVOH segments in EVOH. The detailed quantitative analysis of the morphology performed for all blends showed that the finest dispersion was obtained with the PVOH with the lowest molar mass. The properties of the films as a function of the PVOH content and its molar mass were determined herein. Significant improvement of barrier properties was obtained at moderated water activities (up to aw = 0.6) by using the PVOH with the lowest molar mass. Compared to the neat EVOH material, the oxygen permeability coefficients decreased by a factor 2 by adding 15 vol% PVOH while the thermal and mechanical properties remained similar. 相似文献
12.
Densities of glycerol (1) + tert-butanol (2) mixtures were measured over the temperature range 293.15 to 348.15 K at atmospheric pressure, over the entire
composition range, with a vibrating tube densimeter. Excess molar volumes, apparent and partial molar volumes of glycerol
and tert-butanol, thermal isobaric expansivities of the mixture and partial molar expansivities of the components were calculated.
The excess molar volumes of the mixtures are negative at all temperatures, and deviations from ideality increase with increasing
temperature. Excess molar volumes were fitted to the Redlich–Kister equation. Partial molar volumes of glycerol decrease with
increasing tert-butanol concentration. The temperature dependence of the partial molar volumes of glycerol is characterized by an inversion
at x
2≈0.7. “Negative expansion” of the limiting partial volumes of glycerol was observed. 相似文献
13.
Ultrasonic velocity and density values are measured for aqueous solutions containing 2.00 mol.%, 4.00 mol.%, and 5.00 mol.%
glycine in a temperature range of 15–65°C, 5.50 mol.% glycine (20–65°C), and 6.00 mol.% glycine (25–65°C). Adiabatic compressibilities
(κS) and molar adiabatic compressibilities (KS) are calculated. The values of κS and KS decrease monotonically with an increase in glycine concentrations up to saturation at all the temperatures. The temperature
dependences of κS and κS have minima that are typical of water and aqueous solutions; the positions of the minima depend on the glycine concentration.
The temperature coefficients of the molar compressibility, ∂KS/∂T, change their signs from negative to positive at lower temperatures (by approximately 10 deg) than ∂κS/∂T. 相似文献
14.
15.
Densities (ρ) of glycine, L-alanine, and L-valine in aqueous solutions of MgCl2-6H2O (0.1-0.8 mol kg-1) have been measured at 288.15, and 308.15 K. Apparent molar volumes (V
φ), and limiting partial molar volumes (V
φ
0
) of each amino acid have been calculated. These data were combined with the earlier reportedV
φ
0
values of glycine, L-alanine, and L-valine in aqueous MgCl2·6H2O solutions at 298.15 K in order to describe the temperature dependence behaviour of partial molar quantities. Group contributions
to partial molar volumes have been determined for the amino acids. The trends of transfer volumes (△V
φ
0
) have been interpreted in terms of solute-cosolute interactions on the basis of a cosphere overlap model. Pair and triplet
interaction coefficients have also been calculated from transfer parameters. 相似文献
16.
Alessandro Ulrici Marina Cocchi Giorgia Foca Matteo Manfredini Daniela Manzini Andrea Marchetti Simona Sighinolfi Lorenzo Tassi 《Journal of solution chemistry》2006,35(2):139-159
In this paper, the temperature and composition dependencies of the volumetric behavior are studied for the ethane-1,2-diol
+ 2-methoxyethanol + 1,2-dimethoxyethane + water quaternary system. Density data were collected at different temperatures
ranging from −10 to 80 ∘C and at atmospheric pressure over the whole composition range, 0≤ xi(i = 1, 2, 3, 4)≤ 1. Moreover, we also made use of the results on the six binary (ij) and four ternary (kij) subsystems studied previously. The excess molar volume (VE) data have been fitted to an equation derived from the well-known Redlich–Kister equation and some interesting correlations
were found. Furthermore, in order to represent in an effective way the behavior of the VE = VE(xi) function (and of the derived partial molar quantities) in the quaternary domain, a new algorithm has been developed, which
gives 3D plots where the dependent function is depicted by means of “colored slices” of the tetrahedron corresponding to the
investigated composition quaternary domain. 相似文献
17.
M. M. Mato M. Illobre P. V. Verdes M. I. Paz Andrade 《Journal of Thermal Analysis and Calorimetry》2006,84(1):291-295
Excess molar enthalpies
of the ternary mixture {x1 tert-butyl methyl ether (MTBE)+x2
ethanol+(1–x1–x2) hexane} and, the involved
binary mixtures {x tert-butyl methyl ether
(MTBE)+(1–x) ethanol}, {x tert-butyl methyl ether (MTBE)+(1–x) hexane} and {x
ethanol+( 1–x) hexane} have been
measured at 298.15 K and atmospheric pressure, over the whole composition
range, using a Calvet microcalorimeter. The results were fitted by means of
different variable degree polynomials. 相似文献
18.
Summary Pressure and temperature have significant influence on retention in HPLC. This study investigates the effect of pressure and
temperature on the retention behavior of aromatic hydrocarbons (toluene, ethyl benzene, butyl benzene, pentyl benzene) and
polar, acidic and basic samples (phenol, acetophenone, N,N-dimethyl aniline, benzophenone) on a reversed phase column. The
effect has been studied on non-porous, tetradecyl (C14) coated silica particles. We found that the adsorption-induced decrease of the partial molar volume of the solutes investigated
was between ΔV
m
=5–15 cm3 mol−1. The increment of the decrease of the partial molar volume due to the addition of one CH2 group, for the homologous series of the aromatic hydrocarbons is approximately ΔV
CH2
=2.3 cm3mol−1.
Presented at Balaton Symposium '01 on High-Performance Separation Methods, Siófok, Hungary, September 2–4, 2001. 相似文献
19.
Shear viscosity deviations Δη have been investigated by using density (ρ) and kinematic viscosity (ν) measurements for isobutyric acid + water (IBA + W) mixtures over the entire range of mole fractions at atmospheric pressure
and at two temperatures (301.15 and 315.15 K). This study extends the temperature range from the five other temperatures investigated
in a previous work, 1.055 K≤(T−T
c
)≤14.055 K, both far from and close to the critical temperature. This system exhibits very large positive values of Δη due to increased hydrogen bonding interactions and the correlation length between unlike molecules in the critical region,
and to very large differences between the molar volumes of the pure components at low temperatures. The results were also
fitted with the Redlich–Kister polynomial equations and the recently proposed Herráez correlation equation. Comparisons between
the two models at different temperatures and number of parameters are discussed. We note that, in this system where the shear
viscosity η as a function of mole fraction (x
1) of IBA presents a maximum, experimental data are in agreement with the two correlation models when more than three parameters
are employed, especially for temperatures far from the critical temperature. 相似文献
20.
The apparent molar volumes, V
φ
, of two series of homologous aliphatic carboxylic acids, H(CH2)
n
COOH [n=0–5] and (CH2)
n
(COOH)2 [n=0–5], were determined in dilute aqueous solutions by density measurements at T=298.15 K. Densities were measured using a vibrating-tube densimeter (DMA 5000, Anton Paar, Austria) at T=298.15 K. These results were used to calculate the apparent molar volumes of each solute over the concentration range 0.0050≤m/(mol⋅kg−1)≤0.3000. Values of the apparent molar volumes of undissociated acids Vf(u)0V_{\phi (u)}^{0} were also calculated. The variation of Vf(u)0V_{\phi (u)}^{0} was determined as a function of the aliphatic chain length of the studied carboxylic acids. 相似文献