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771.
772.
H测定过MgSO_4-C_2H_5OH-H_2三元系在25℃、50℃、75℃的液固平衡和部分不饱和溶液汽液平衡的总压和分压。本文补充了30℃、0℃和-5℃时的溶解度数据,得到分层温度和浓度范围,绘出了溶解度图。测定了25℃和30℃饱和溶液的密度,粘度和平衡总压力。根据Jaques“假二元系”理论用Wilson、Uniquac和NRTL活度方程计算了溶 相似文献
773.
Marga Mitkova Zorka Boncheva-Mladenova 《Monatshefte für Chemie / Chemical Monthly》1989,120(8-9):643-650
Summary The glass forming region in the system Se-Te-Ag was determined, the presence of glassy phases was proved by electron microscope and X-ray analysis. The properties of the synthesized glasses (vitrification temperature, microhardness, density, molar volume, light transmission and electrical conductivity) were investigated and discussed in terms of their composition.
Glasbildungsgebiet und einige Eigenschaften der Gläser des Systems Se—Te—Ag
Zusammenfassung Es wurde das Glasbildungsgebiet im System Se-Te-Ag bestimmt. Der glasartige Zustand der erhaltenen Phasen wird auf Grund röntgenographischer und elektronenmikroskopischer Untersuchungen nachgewiesen. Die Eigenschaften der erhaltenen Gläser (Transformationstemperatur, Mikrohärte, Dichte, Molvolumina, Lichttransmission und elektrische Leitfähigkeit) wurden untersucht und im Zusammenhang mit ihrer Zusammensetzung diskutiert.相似文献
774.
One of the main reasons for the underutilization of ultrafiltration has been the lack of experimental data on transmission of proteins for complex systems and its corresponding theoretical analysis. Of course, the presence of fouling coupled with concentration polarization have had their share in making ultrafiltration operation a difficult one to understand. In the present study, the systematic ultrafiltration of 3-protein mixture, namely lysozyme, myoglobin and ovalbumin, has been carried out using a hydrophilic 30,000 molecular weight cut off membrane. The experimental data of individual protein transmission in ternary mixture showed a very low transmission (as low as 3% for ovalbumin) to a very high transmission (as high as 90% for lysozyme) of proteins for different operating conditions. This behaviour of each protein in the mixture was analyzed using combined concentration polarization and irreversible thermodynamics model. The parameters of the modeled values gave a very good fit with experimental data and the resulting analysis indicated some interesting findings, which are discussed in this paper. The comparison of parameters obtained for single protein solution and the ternary protein solution showed some unusual results that point to the presence of the protein–protein and protein–membrane interactions. 相似文献
775.
D.?V.?Bavbande R.?Mishra J.?M.?JunejaEmail author 《Journal of Thermal Analysis and Calorimetry》2004,78(3):775-780
Reaction kinetics of the formation of TiC by calciothermic reduction of TiO2 in presence of carbon have been investigated using thermal analysis (TG-DTA) of a powder mixture of TiO2, Ca, and C in argon atmosphere at different heating rates. Both the reaction initiation and the peak temperatures are found to increase with heating rates. The appearance of exothermic peaks in the DTA plots after Ca melting indicates the reduction of TiO2 by liquid calcium and formation of TiC by in-situ reaction of Ti with C. The apparent activation energy of the process has been found to be 170.8±0.5 kJ mol–1. 相似文献
776.
三元配合物停流—动力学分析法测定铝的研究 总被引:8,自引:0,他引:8
利用自动化动力学分析装置研究了铝与3,5-二溴水杨基荧光酮及表面活性剂形成三元配合物的动力学性质,测定了质子、显色剂及表面活性剂的反应级数及反应活化能。提出了一种简便、快速、精密和准确的分析方法,并用于人发中痕量铝的测定。方法灵敏度较高(ε=1.11×10~5L/mol·cm),大多数元素的干扰均可用动力学方法消除,优于其它测定铝的多元配合物体系。 相似文献
777.
Crystal Structures and Spectroscopic Investigations of Ternary CuII-Complexes with Bicyclic Dicarboxylic Acids and N,N-Donor Ligands The synthesis of coordination compounds [CuLdam] · 3H2O (H2L = 7-oxa-bicyclo[2.2.1]heptane-2-exo,3-cis-dicarboxylic acid ( 1 ) and its 1-methyl-derivative ( 2 ); dam = ethylendiamine, 1,2- and 1,3-propylendiamine, 2,2′-dipyridyl, 1,10-phenanthroline) has been described. Results of visible and IR spectroscopy and magnetic data are given. In the result of X-ray analyses of [CuL1dipy] · 3H2O ( 1 d ) and [CuL2en] · 3H2O ( 2 a ) the dicarboxylate anions of 1 and 2 proved to be tridentate chelating ligands. In 1 d the Cu atom has an approximately square-pyramidal coordination with the bridging O atom in the apical position. In 2 a , however, the coordination number is extended to six by an O atom of a second [CuL2en] unit resulting in a centrosymmetric complex dimer with octahedrally coordinated Cu atoms. The water molecules do not participate in the coordination of the Cu atoms and form a complicated system of hydrogen bonds in the crystal. 相似文献
778.
In this review, a summary of our published results, completed with new unpublished data are considered together with some
of other authors’ publications, making an attempt to reveal the mechanism of the third element co-deposition in electroless
Ni–P plating and to define its influence on the ternary coatings’ properties. A model explaining the triple role of Cu added
to the solution for electroless (EL) Ni–P plating is described: as a stabilizer [Cu(I)]; as an accelerator; and as a stability-affecting
agent, forming a dispersed solid phase in the solution. The disproportionation reaction of Cu(I) has been taken into account.
A planned experiment was performed using full-effect factorial design with two levels of three process variables, and the
response surfaces were constructed. The interaction between the factors was revealed. The results are in harmony with the
aforementioned model. In low-tin Ni–Sn–P coatings, the alloy components are uniformly distributed both on the surface and
through the thickness. In contrast, high-tin coatings exhibit three-dimensional areas enriched in Sn and impoverished in Ni
and P. As the reason for their formation, the disproportionation reaction of Sn(II) is suggested, supposed to be locally predominant
over the hypophosphite oxidation. EL deposition of pure Sn onto Ni–Sn–P substrates is shown. The inclusion of Cu or Sn in
EL Ni–P increases the thermal stability of amorphous state, ensures the preservation of a paramagnetic behavior and improves
the corrosion resistance.
Dedicated to the 70th birthday of Professor A. Vaskelis. 相似文献
779.
K3BiSe3, Rb3BiSe3, and Cs3BiSe3 – Derivatives of the Th3P4 Structure Type The compounds K3BiSe3, Rb3BiSe3, and Cs3BiSe3 were synthesized by heating mixtures of Bi2O3 and the respective alkalicarbonate in a stream of hydrogen saturated by selenium at 850°C. Thin crystals of the compounds appear red in transmitted light. They crystallize isostructural with Na3AsS3, space group P213, lattice constants a = 9.771(5) Å, a = 10.161(3) Å, and a = 10.587(5) Å for K3BiSe3, Rb3BiSe3, and Cs3BiSe3, respectively. The Na3AsS3 structure type is a derivative of the Th3P4 structure type. 相似文献
780.
Genevieve Roux-Desgranges Alain H. Roux Jean-Pierre E. Grolier André Viallard 《Journal of solution chemistry》1982,11(5):357-375
Densities and heat capacities of the ternary system water-sodium dodecylsulfate — n-butanol were measured at 25°C over the complete alcohol mole-fraction or solubility range. Apparent and partial molar volumes and heat capacities of n-butanol were derived and have been analyzed as a function of the concentration of both the surfactant and the alcohol. Characteristic changes suggest that, at low concentrations, n-butanol is partially solubilized in mixed micelles but, in concentrated alcohol solutions, n-butanol largely exists in the form of microaggregates stabilized by the surfactant. Results would also suggest that at low concentrations of n-butanol another transition zone occurs in the micellar structure around 0.2–0.3 mol-kg–1 in sodium dodecylsulfate. 相似文献