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991.
A.?P.?LeushinaEmail author L.?A.?Kolesnikova E.?V.?Makhanova V.?P.?Zlomanov 《Russian Journal of Electrochemistry》2005,41(6):639-645
Optimum compositions of ion-selective membranes in quasi-binary systems CuCl-CdCl2, LiCl-CdCl2, and In2S3-InCl3 are selected by a method of coulometric titration in cells with solid electrolytes. Transport numbers for ions are close to unity for the optimum compositions; transport numbers for electrons are vanishingly small (
≺10−3 to 10−4); the electroconductivity is equal to ≈ 10−3 S cm−1 at 200°C; the diffusion coefficients for the current-producing component are on the order of 10−6 to 10−7 cm2 s−1. When using a solid electrolyte of the composition CuCl-CdCl2, which contains 30 mol % CdCl2, methods of emf and electroconduction reveal that the region of homogeneity of copper(I) selenide falls in the region of compositions Cu1.33Se-Cu2.67Se.__________Translated from Elektrokhimiya, Vol. 41, No. 6, 2005, pp. 721–727.Original Russian Text Copyright © 2005 by Leushina, Kolesnikova, Makhanova, Zlomanov.Published on the basis of a report delivered at the VII Meeting on Fundamental Problems in Solid-State Ionics (Chernogolovka-2004). 相似文献
992.
L. Barral F.J. Díez S. García-Garabal J. López B. Montero R. Montes C. Ramírez M. Rico 《European Polymer Journal》2005,41(7):1662-1666
Lifetime of the epoxy system formed by diglycidyl ether of bisphenol A, DGEBA/4,4′-diaminediphenylmethane, DDM, modified with the silsesquioxane, glycidylisobutyl-POSS, was calculated from thermogravimetric analysis. The activation energy of the decomposition of this system was evaluated by the integral method developed by Flynn-Wall-Ozawa (E = 88.9 ± 2.1 kJ mol−1) and by Coats and Redfern method (E = 85.2 ± 1.5 kJ mol−1). The kinetic parameters have been used to estimate the lifetime of the system POSS/DGEBA/DDM. The obtained results by two different ways are similar. 相似文献
993.
A molecular dynamics study of the dark adapted visual pigment rhodopsin molecule was carried out. The interaction of the chromophore
group, 11-cis-retinal, with the nearest amino acid residues in the chromophore center of the molecule, namely, in the region of the protonated
Schiff base linkage, was analyzed. Most likely, the interaction of the CH=NH bond with the negatively charged amino acid residue
Glu113 cannot be described as a simple electrostatic interaction of two oppositely charged groups. One can propose that not
only Glu113 but also Glu181 and Ser186 are involved in stabilization of the protonated Schiff base linkage. Accord-ing to
calculations, Glu181 interacts, as the counter-ion, with the Schiff base indirectly via Ser186. The intramolecular mechanisms of protonated Schiff base stabilization in rhodopsin are discussed.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 19–27, January, 2007. 相似文献
994.
A. Marcinčin A. Ujhelyiová K. Marcinčin P. Alexy 《Journal of Thermal Analysis and Calorimetry》1996,46(2):581-595
The effects of the organic pigments C.I.P. RED 177 and C.I.P. Yellow 83 as nucleating agents on the crystallization of polypropylene were studied by DSC. The anthraquinone pigment exerted a significant effect, resulting in structural modifications with lower melting point, and particularly the -modification. The DSC curves exhibit four transition regions, with the following temperature intervals: I. 415–417 K, II. 423–425 K, III. 430–432 K and IV. 438–439 K. For evaluation of the -nucleation effect of pigments, the ratio (H
1+H
2)/(H
3+H
4) was suggested. 相似文献
995.
T. M. Polyanskaya 《Journal of Structural Chemistry》2006,47(5):887-893
A single crystal X-ray diffraction study of a new iodine-containing cluster compound 9-(pyridine)-11-iodo-decahydro-7,8-dicarba-nido-undecaborane [9-C5H5N-11-I-7,8-C2B9H10] has been performed. Crystal data: C7H15B9NI, M = 337.39, monoclinic, space group P21/c, unit cell parameters: a = 9.348(1) Å, b = 11.159(1) Å, c = 13.442(2) Å, β = 98.13(1)°, V = 1388.1(5) Å3, Z = 4, d calc = 1.614 g/cm3, T = 295 K, F(000) = 648, μ = 2.276 mm?1. The structure was solved by a direct method and refined in the full-matrix anisotropic approximation (isotropic for hydrogen atoms) to final agreement factors R 1 = 0.0254, wR 2 = 0.0454 for 2437 I hkl ≥ 2σI from 3590 measured I hkl (an Enraf-Nonius CAD-4 diffractometer, λMoK α , graphite monochromator, θ/2θ-scanning). The molecules are joined into a supramolecular assembly by hydrogen bonds X-H?I (X = B, C). 相似文献
996.
997.
Masatoshi Taniguchi Ken-ichi SuzumuraKoji Nagai Tomihisa KawasakiTetsu Saito Jun TakasakiKen-ichi Suzuki Shigeo FujitaShin-ichi Tsukamoto 《Tetrahedron》2003,59(25):4533-4538
The isolation and structure elucidation of YM-254890, a novel Gq/11 inhibitor from Chromobacterium sp. QS3666, is described. The gross structure was determined by one- and two-dimensional NMR studies and mass spectrometry. YM-254890 is a cyclic depsipeptide containing uncommon amino acids; β-hydroxyleucine (two residues), N,O-dimethylthreonine and N-methyldehydroalanine. YM-254890 exists as a mixture of two conformers in a variety of NMR solvents, and the distinction between major and minor conformers appears to lie in the geometry of the amide bond between 3-phenyllactic acid and N-methyldehydroalanine. The absolute stereochemistery was elucidated by Marfey's analysis and chiral HPLC analysis of the acid hydrolysate of YM-254890. 相似文献
998.
This paper concerns the application of excess adsorption isotherms, measured for solvent mixture/adsorbent systems, to the characterization of TLC data. For this purpose the excess adsorption isotherms for three liquid mixtures: cyclohexane/ benzene, benzene/acetone, and carbon tetrachloride/ethyl acetate on silica gel at 20°C have been measured. These mixtures have been used as binary mobile phases in TLC measurements. It has been shown for a given solute in binary mobile phase that the quantity RM is a simple function of the excess adsorption. Parameters of this function have been used to characterize chromatographic systems with binary mobile phases. 相似文献
999.
B. S. Boyanov 《Journal of Thermal Analysis and Calorimetry》1995,44(3):707-716
Conditions were established and individual and mixed ferrites with the general formula CuxZn1?xFe2O4 (x=0; 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8; 1.0) were synthesized from the CuO?ZnO?Fe2O3 system. X-ray phase analysis, Mössbauer spectroscopy and microscopic examinations revealed that the obtained ferrites are monophase samples. A magnetic device was attached to the Q-Derivatograph (MOM, Hungary) and successfully used for sample investigation in a magnetic field, and in particular for Curie (Neel) temperature determination. The ferrite composition and the thermal treatment conditions were shown to correlate with the Neel temperature of the synthesized ferrites. 相似文献
1000.
有机-无机纳米复合材料的研究在当前纳米科学技术的发展中占有重要地位,开创了材料与催化科学研究的新纪元。自从10年前首次合成纳米孔无机材料MCM-41至今,该领域研究不断深入,已展现出广阔的应用前景。当客体有机分子分散于纳米孔道内部时,其分子性质将产生明显变化。本文结合作者近期研究成果,力图从实验与理论两方面阐明在纳米复合体系中客体分子性质变化的原因。 相似文献