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1.
Yong-Hong Hu Zhao-Guo Chen Wen-Ge Yang Ying Shi Hui-Ling Sun Yong-Lan Li 《Journal of solution chemistry》2013,42(1):102-110
In an equilibrium vessel, the solubilities of succinic acid in binary aqueous ethanol solvents were measured by the analytical stirred-flask method with the temperature ranging from 278.15 to 333.15 K at atmospheric pressure. Data on the corresponding solid–liquid equilibrium of succinic acid in binary aqueous ethanol solutions are essential for industrial design and further theoretical studies. The effect of solvent composition and temperature on the solubility is discussed. The solubility data were correlated with the Combined Nearly Ideal Binary Solvent/Redlich-Kister (CNIBS/R-K) model. The solubility measured in this study can be used for succinic acid purification or optical resolution by the preferential crystallization procedure. 相似文献
2.
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
3.
Alexandra Golikova Artemiy Samarov Maya Trofimova Sevastyan Rabdano Maria Toikka Oleg Pervukhin Alexander Toikka 《Journal of solution chemistry》2017,46(2):374-387
The chemical equilibrium (CE) for the quaternary reacting system ethanol–acetic acid–ethyl acetate–water was studied at 303.15, 313.15 and 323.15 K and atmospheric pressure. The CE compositions were determined by gas chromatography and nuclear magnetic resonance analytical methods. The thermodynamic constants of CE at 303.15, 313.15 and 323.15 K were calculated based on the obtained experimental data with the use of the NRTL model. 相似文献
4.
G. H. Zimmerman Philip W. Scott Wendy Greynolds Dmitriy Mayorov 《Journal of solution chemistry》2009,38(4):499-512
Electrical conductance measurements were made on dilute solutions of hydrochloric acid to 458 K and 1.4 MPa with a flow instrument.
These measurements agree well with those of previous authors. The conductance theory of Fuoss and Hsia as given by Fernandez-Prini
(FHFP), was fit to these measurements. It was found that this theory adequately described the present results with a single
parameter, the limiting conductance at infinite dilution Λ°(HCl). Within their estimated accuracy, reported literature results of Λ°(HCl) between 264.15 and 579 K and high pressures were found to be represented by a five-parameter equation that was a function
of the solvent viscosity, temperature and pressure. This equation along with the FHFP theory permits accurate calculation
of the conductance of dilute hydrochloric acid solutions at high temperatures and pressures.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users. 相似文献
5.
Viscosity deviations from ideal mixing for 1,4-dioxane + water mixtures over the entire range of composition at temperatures
of (293.15, 303.15 and 313.15) K and atmospheric pressure were calculated from experimental viscosity data presented in a
previous work. The temperature range was extended to 323.15 K with data from the literature. This system exhibits very large
positive deviations due to strong heteromolecular interactions and also due to size differences of the unlike molecules. The
viscosity data as well as their corresponding relative functions were used to test the applicability of two correlative equations:
the reduced Redlich-Kister equation and the recently proposed Herráez equation. These relative functions are important to
reduce the effect of temperature and, consequently, to reveal the effects of different types of interactions. Their correlation
abilities at different temperatures, and using different numbers of parameters, are discussed for the case of limited experimental
data. Generally, good agreement between experimental and calculated data was obtained with both equations provided more than
three parameters were employed. 相似文献
6.
Apparent molar volumes V
φ,B of n-propylamine, n-butylamine, di-n-propylamine, di-n-butylamine, triethylamine, tri-n-propylamine, and tri-n-butylamine in 1,4-dioxane and in oxolane (tetrahydrofuran) have been determined at 303.15 K using a high-precision Anton
Paar vibrating-tube densimeter (model DMA 60/602). The limiting partial molar volumes
and limiting excess partial molar volumes
are analyzed and interpreted in terms of solute-solvent interactions and structural effects of the molecules.
Analyses were made of the contributions of specific interactions to the partial molar volumes of these primary, secondary
and tertiary amines in 1,4-dioxane and oxolane using the Terasawa model, scaled particle theory (SPT) and hard-sphere theory
(HST). The ERAS model has also been applied to estimate the apparent molar volumes and excess apparent molar volumes of alkylamine
solutions in 1,4-dioxane and oxolane. 相似文献
7.
Raphael da C. Cruz Rosana J. Martins Márcio J. E. de M. Cardoso Oswaldo E. Barcia 《Journal of solution chemistry》2009,38(8):957-981
Density measurements were made for binary aqueous solutions of polyethylene glycol at seven temperatures: 283.15, 288.15,
293.15, 298.15, 303.15, 308.15, and 313.15 K. Polyethylene glycol samples with nominal average molar masses of 3000 g⋅mol−1 (PEG 3000), 6000 g⋅mol−1 (PEG 6000), 10000 g⋅mol−1 (PEG 10000) and 20000 g⋅mol−1 (PEG 20000) were used. These results were used to determine the specific volumes of solutions with solute-to-solvent mass
ratios (mass of the solute/mass of the solvent) in the range 0.0546 to 1.4932 for PEG 3000, from 0.0553 to 1.4986 for PEG
6000, from 0.0552 to 1.2241 for PEG 10000, and from 0.0530 to 1.2264 for PEG 20000. The differences between the specific volume
of a solution and the specific volume of the pure solvent, at a given temperature, were represented by a virial-type equation
in terms of solute concentration. The first-order coefficient of the expansion is the partial specific volume of the solute
at infinite dilution. The higher-order coefficients are related to the contribution of pairs, triplets, and higher-order solute
aggregates, according to the Constant-Pressure Solution Theory. The functional dependence of the virial coefficients upon
temperature is discussed in terms of solute-solute and solute-solvent interactions. The effect of the PEG molar mass on the
partial specific volume of solute at infinite dilution, as well as the contributions of pairs of solute molecules to the solution
volume, are also investigated. The apparent specific volume, apparent specific expansibility, apparent specific expansibility
at infinite dilution and virial coefficients of the apparent specific expansibility are also presented. 相似文献
8.
Experimental molar heat capacity data (Cp
m) and excess molar heat capacity data (CpEm\mathit{Cp}^{\mathrm{E}}_{\mathrm{m}}) of binary mixtures containing water + (formamide or N,N-dimethylformamide or dimethylsulfoxide or N,N-dimethylacetamide
or 1,4-dioxane) at several compositions, in the temperature range 288.15 K to 303.15 K and atmospheric pressure, have been
determined using a modified 1455 PAAR solution calorimeter. The excess heat capacities are positive for aqueous solutions
containing 1,4-dioxane, N,N-dimethylformamide or dimethylsulfoxide, negative for solutions containing water + formamide and
show a sigmoid behavior for mixtures containing water + N,N-dimethylacetamide, over the whole composition range. The experimental
excess molar heat capacities are discussed in terms of the influence of temperature and of the organic solvent type present
in the binary aqueous mixtures, as well as in terms of the existing molecular interactions and the organic solvent’s molecular
size and structure. 相似文献
9.
Evgeniy V. Ivanov 《Journal of solution chemistry》2010,39(3):343-354
Densities of aqueous solutions of tetramethyl-bis-urea (TMbU) with solute mole fractions ranging up to 7.0×10−2 have been measured with an uncertainty of 1.5×10−5 g⋅cm−3, at 278.15, 298.15, 318.15, and 338.15 K using a vibrating-tube densimeter. The partial molar volumes and expansibilities
of TMbU (down to the infinite dilution) and water have been computed. The effects of solute concentration and temperature on the
volume packing changes, caused by dissolution (and hydration) of TMbU in an aqueous medium, have been considered. 相似文献
10.
Heats of solution, Δsol
H
m
, of L-cysteine, L-serine and L-asparagine amino acids have been measured at different concentrations of aqueous ethanol,
propanol and 2-propanol at 298.15 K using solvation calorimetry. These data are compared with the results reported earlier
for L-alanine in ethanol. The enthalpic coefficients, h
xy
, of the solute-organic cosolvent pair interaction in water have been obtained from the McMillan-Mayer approach and the data
have been interpreted in terms of various interactions and changes in solvent structure. 相似文献
11.
Gibbs energies of activation for viscous flow of binary water (1) + dimethyl sulfoxide (2) mixtures, Δμ
12○, and of lysozyme (3) in corresponding ternary mixtures, Δμ
3○, were determined at 298.15 K. The binary mixtures have a maximum in the value of the excess quantity for Δμ
12○ at a dimethyl sulfoxide mole fraction of x
2≈0.31. The values of Δμ
3○ are larger than Δμ
12○ at all values of x
2, even when normalized by their molar volumes, suggesting that the solvents interact more strongly with lysozyme than with
themselves. The values of Δμ
3○ significantly increased in the range of x
2=0.3 to 0.4 because of an increase in solvent-lysozyme interactions, which resulted from an increase in the accessible surface
area of lysozyme that was exposed by its unfolding. The mean value obtained for Δμ
3○ per amino acid of lysozyme at x
2=0.2 is greater than that for hydrophobic amino acids, indicating that the solvent interacts with hydrophilic amino acids
more strongly than with hydrophobic ones. 相似文献
12.
Jaka Horvat Marija Bešter-Rogač Cveto Klofutar Darja Rudan-Tasic 《Journal of solution chemistry》2008,37(9):1329-1342
The viscosities of aqueous solutions of lithium, sodium, potassium, rubidium and caesium cyclohexylsulfamates were measured
at 293.15, 298.15, 303.15, 313.15 and 323.15 K. The relative viscosity data were analyzed and interpreted in terms of the
Kaminsky equation, η
r=1+Ac
1/2+Bc+Dc
2. The viscosity A-coefficient was calculated from the Falkenhagen-Dole theory. The viscosity B-coefficients are positive and relatively large. Their temperature coefficient ∂
B/∂
T is negative or near zero for lithium and sodium salts whereas for potassium, rubidium and caesium salts it is positive. The
viscosity D-coefficient is positive. This was explained by the size of the ions, structural solute–solute interactions, hydrodynamic
effect, and by higher terms of the long-range Debye-Hückel type of forces. From the viscosity B-coefficients the thermodynamic functions of activation of viscous flow were calculated. The limiting partial molar Gibbs
energy of activation of viscous flow of the solute was divided into contributions due to solvent molecules and the solute
in the transition state. The activation energy of the solvent molecules was calculated using the limiting Gibbs energy of
activation for the conductance of the solute ions. The activation energy of the solvent molecules was then discussed in terms
of the nature of the alkali-metal ions and their influence on the structure of water. The limiting activation entropy and
enthalpy of the solute for activation of viscous flow were interpreted by ion-solvent bond formation or breaking in the transition
state of the solvent. The hydration numbers of the investigated electrolytes were calculated from the specific viscosity of
the solutions. 相似文献
13.
Solution densities over the temperature range 288.15 to 328.15 K have been measured for aqueous solutions of N-acetylarginamide monotrifluoroacetate and sodium trifluoroacetate, from which the partial molar volumes at infinite dilution,
V2oV_{2}^{\mathrm{o}}, were determined. The partial molar heat capacities at infinite dilution, Cp,2oC_{p,2}^{\mathrm{o}}, were also determined for these solutes over the same temperature range. These V2oV_{2}^{\mathrm{o}} and Cp,2oC_{p,2}^{\mathrm{o}} results, along with relevant data taken from the literature, have been used to calculate the contributions of the protonated
arginyl side-chain to the thermodynamic properties. These new side-chain values were critically compared with those obtained
previously using alternative side-chain model compounds. 相似文献
14.
Kaiyu Zhao Long Li Jing Li Yafei Guo Yuanhui Liu Tianlong Deng 《Journal of solution chemistry》2018,47(5):827-837
Densities for aqueous solutions of magnesium tetraborate MgB4O7(aq) at the molalities of (0.00556–0.03341) mol·kg?1 were measured with an Anton Paar Digital vibrating-tube densimeter at temperature intervals of 5 K from 283.15 to 363.15 K and 0.1 MPa. Apparent molar volumes were obtained based on the experimental density data, and the 3D diagrams of the apparent molar volume (V ? ) of MgB4O7(aq) against temperature (T) and molality (m) were plotted. On the basis of the Vogel–Tamman–Fulcher equation, the coefficients of the correlation equation for densities of MgB4O7(aq) against temperature and molality were parameterized. According to the Pitzer ion-interaction model of the apparent molar volume, the temperature correlation equations of Pitzer single-salt parameters F(i,p,T)?=?a0?+?a1?×?T?+?a2?×?T 2?+?a3/T?+?a4?×?ln(T)?+?a5?×?T 3 (where T is temperature in Kelvin, a i are model parameters) for MgB4O7 were obtained for the first time. 相似文献
15.
Gavin R. Hedwig 《Journal of solution chemistry》2009,38(10):1315-1331
Solution densities over the temperature range 288.15 to 313.15 K have been measured for aqueous solutions of the nucleosides
inosine, 2′-deoxyinosine, and 2′-deoxyguanosine, from which the partial molar volumes of the solutes at infinite dilution,
V
2o, were obtained. The partial molar expansions for the nucleosides at infinite dilution and 298.15 K, E
2o {E
2o=(∂
V
2o/∂
T)
p
}, were derived from the V
2o results. The V
2o values at 298.15 K for the two sugars D-ribose and 2-deoxyribose also have been determined. The partial molar heat capacities
at infinite dilution for all the solutes, C
p,2o, have been determined at 298.15 K. These V
2o,E
2o, and C
p,2o results are critically compared with all of the results available from the literature, and the use of group additivity to
evaluate these solution thermodynamic properties for the sparingly soluble nucleoside guanosine is explored. 相似文献
16.
Liquid–liquid equilibrium tie line data were determined for three quaternary systems water + ethanol + diethyl carbonate+n-heptane, water + ethanol + 1,1-dimethylethyl methyl ether + diethyl carbonate, and water + 1,1-dimethylethyl methyl ether + diethyl
carbonate+n-heptane at 298.15 K and atmospheric pressure. The experimental liquid–liquid equilibria results have been correlated using
a modified UNIQUAC model and an extended UNIQUAC model, both with multicomponent interaction parameters in addition to the
binary ones. 相似文献
17.
Enthalpies of solution and apparent molar volumes have been determined for propionamide in aqueous methanol, ethanol and propanol solutions at 298.15 K using a C-80 microcalorimeter and a DMA60/602 vibrating-tube digital densimeter. The enthalpic and volumetric interaction coefficients have been calculated. Using the present results along with results from previous studies for formamide, the pair-interaction coefficients are discussed from the perspective of dipole-dipole and structural interactions. In addition, the triplet interaction coefficients are interpreted by using the solvent-separated association mechanism. 相似文献
18.
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
19.
Takayoshi Kimura Tasunori Suzuki Keisuke Takata Akina Soga Yutsa Nomoto Tadashi Kamiyama Yousuke Nakai Hideo Matsui Masao Fujisawa 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1467-1474
The molar excess enthalpies of eight systems of butylamines + propanols were determined at 298.15 K using a twin-microcalorimeter. All excess enthalpies were exothermic and large. An equilibrium constant K 1 expressed in terms of mole fractions and standard thermodynamic properties of formation (Δf H, Δf G, Δf S) of 1:1 complex were evaluated by ideal mixtures of monomeric molecules and their associated complexes. Concentration dependence of the FT-Raman spectrum showed systematic changes of bands. Spectroscopic considerations based on this and ab initio calculations on molecules were performed at the Mp2/6-311G(d,p) level of theory. Interaction energies between butylamine and propanol were calculated by the supermolecular and NBO methods. The results were discussed with previous results to clarify the steric and positional effect of the amino and hydroxyl group. 相似文献
20.
Enthalpies of mixing of ethanol solution of R- and S-enantiomers of limonene in large concentration have been measured at 298.15 K. The enthalpies of mixing were negligibly small
for all concentrations. Enthalpies of mixing showed negative in less than 30 mol%, but positive in more than the high concentration
of limonenes. The heterochiral solutions were more stable than each of the homochiral solutions in dilute solutions. The concentration
dependence on enthalpies of mixing in dilute concentration of less than 10 mol% was much sharper in inclination than the dense
solutions limonene. 相似文献