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41.
Isothermal pressure (p)-mass fraction (w) phase diagrams were measured for CO2 + tetradecanoic acid at six temperatures from 328.2 K to 373.2 K and for CO2 + docosane at four temperatures from 343.2 K to 393.2 K as well as isobaric temperature (T)-mass fraction (w) phase diagrams for both systems at 34.5 MPa. In addition the isothermal and isobaric Gibbs phase prisms at 373.2 K and 34.5 MPa respectively were determined for the ternary system CO2 + tetradecanoic acid + docosane, and and isobaric miscibility window was found between 333 K and 385 K at 34.5 MPa. 相似文献
42.
O. D. Bonner 《Journal of solution chemistry》1982,11(5):315-324
Osmotic and activity coefficients are reported for sorbitol over the range 1.8–11.1m with NaCl as the reference and 1.8–7.6m with KCl as the reference electrolyte. The osmotic coefficients over the range 0–3.7m are identical with those reported earlier by Robinson. It was found that the activity coefficients of sorbitol are uniformly about four percent lower than those of dextrose. Activity coefficients of trace quantities of NaCl in concentrated sorbitol solutions are about one-half of their value in pure NaCl solutions while the activity coefficients of trace quantities of sorbitol in concentrated NaCl solutions are about one-third of their value in pure sorbitol solutions. Potassium chloride lowers the activity coefficient of sorbitol less than does sodium chloride in solutions of similar water activity. Sorbitol lowers the activity coefficients of potassium chloride in concentrated solution but actually elevates them in dilute solutions. 相似文献
43.
44.
三元配合物钯(Ⅱ)-2,2''-联吡啶-L-天冬氨酸与DNA作用研究 总被引:1,自引:0,他引:1
The ternary complex Pd(Ⅱ)-2,2‘-bipyridine-L-asparagic acid was synthesized and characterized by elemental analysis, IR-spectra and molar conductance. The formula of the complex is Pd(bipy)(L-asp). The interaction of the complex with DNA has been studied by UV-spectra, fluorescence spectra, CD-spectra and gel electrophoresis. The results showed that the interaction of the complex with DNA performed mainly in intercalative mode and the extent of interaction was dependent on the concentration of the complex. 相似文献
45.
Diffusion coefficients of copper sulfate-water and copper sulfate-sulfuric acid-water solutions have been determined at 25°C using conductimetric and diaphragm-cell techniques. The ternary diffusion measurements indicate that diffusion of sulfuric acid can produce large counterflows of copper sulfate and vice versa. If diffusion of copper sulfate in aqueous sulfuric acid solutions is treated as a binary process, the measured apparent diffusivities of copper sulfate can be 1 to 8% lower than the salt's true diffusivity. Equations are developed to predict transport coefficients from the concentrations and mobilities of the diffusing species. 相似文献
46.
综述了近8年来液相平行合成和组合合成中应用的不同技术, 包括可溶性载体、氟合成技术、离子液体、固相试剂树脂以及低聚乙烯二醇(OEG)衍生物的应用等几方面内容. 论述了它们的基本原理以及相关的应用实例, 并着重强调了目标化合物的分离纯化方法. 相似文献
47.
S. M. Bardavid G. C. Pedrosa M. Katz M. A. Postigo P. García 《Journal of solution chemistry》1996,25(11):1125-1135
Exces molar volumes, and excess viscosities of then-hexane+dichloromethane+tetrahydrofuran system have been determined at 25°C by measuring densities and viscosities. Different expressions exist in the literature to predict these excess properties from binary data. The empirical correlation of Cibulka is shown to be the best in this system. 相似文献
48.
The formation of mixed adsorbed layers has been tested for ternary mixtures containing a specifically adsorbed component—acetone and binary solvent benzene +n-hepane. The specific excess adsorption isotherms from the liquid phase were measured on silica gel samples partially dehydroxylated. The competition of liquid components for silica surface is discussed on the basis of changes in the mixed solvent composition. 相似文献
49.
《Surface and interface analysis : SIA》2006,38(9):1249-1251
Progression studies have been followed from Cu(111)‐ and Cu(100)Sn binaries to Cu(111)‐ and Cu(100)SnSb ternary‐alloy systems under the same experimental conditions. The segregation behaviour of Sn in the two orientations are explained. It is found that the kinetic segregation profiles of Sn in the ternary alloys shift to lower temperatures as compared to that in the binary. The Sn profile shift is mainly due to the decrease in the activation energy of Sn in the ternary systems. For a particular Cu orientation, the other segregation parameters that the Sn profiles depend on, like the pre‐exponential factor, segregation energy and the interaction coefficient, are found to be the same in the two systems. There is also a change in the equilibrium segregation profiles of Sn. In the ternary system, site competition between Sn and Sb causes the Sn to suffer exponential desegregation and eventual displacement from the surface. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
50.
S.?Didaoui-NemouchiEmail author A.?Ait-Kaci M.?Rogalski 《Journal of Thermal Analysis and Calorimetry》2005,79(1):85-88
Enthalpies of mixing H have been measured for liquid binary mixtures of diisopropylether (DIPE)+benzene or cyclohexane and for liquid ternary mixtures diisopropylether+benzene+cyclohexane at 303.15 K and constant pressure using a C80 calorimeter. A Redlich-Kister type equation was used to correlate experimental results. 相似文献