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11.
S Çak?r E Co?kunP Naumov E Biçer? Bulut H ?çbudakO Çak?r 《Journal of Molecular Structure》2002,608(1):101-107
Aspartame adduct of copper(II) chloride Cu(Asp)2Cl2·2H2O (Asp=aspartame) is synthesized and characterized by elemental analysis, FT IR, UV/vis, ESR spectroscopies, TG, DTG, DTA measurements and molecular mechanics calculations. Aqueous solution of the green solid absorbs strongly at 774 and 367 nm. According to the FT IR spectra, the aspartame moiety coordinates to the copper(II) ion via its carboxylate ends, whereas the ammonium terminal groups give rise to hydrogen bonding network with the water, the chloride ions or neighboring carboxylate groups. The results suggest tetragonally distorted octahedral environment of the copper ions. 相似文献
12.
Orlov I. S. Moiseeva A. A. Butin E. P. Egorov M. P. 《Russian Chemical Bulletin》2002,51(10):1961-1962
An unusual reaction of diaminogermylene and diaminostannylene with sterically hindered phenols which leads to the formation of stable phenoxyl radicals in high concentrations was found. The reaction mechanism was proposed. Amides [(Me3Si)2N]2E (E = Ge, Sn) were investigated electrochemically. 相似文献
13.
本文概述了配位聚合载体化催化剂的ESR研究进展,介绍了载体研究、活性中心研究及计算机模拟技术研究方面的发展概况. 相似文献
14.
V. A. Livshits B. G. Dzikovskii V. P. Tsybyshev B. B. Meshkov 《Russian Chemical Bulletin》1996,45(7):1563-1571
Isotherms of the binding of dodecyl sulfate anions (DDS–)and Na+ counterions during their coadsorption with a nonionic polymer. proxanol (PR). at the interface of dodecane-water emulsions have been measured by conductometry and Na-selective potentiometry. The adsorption of DDS– and PR is concurrent. The affinity constant of PR to the interface determined by the Langmuir model decreases as the concentration of PR increases, and the surface concentration of DDS– tends to a nonzero limiting value at high concentrations of PR. The surface (o) and electrokinetic () potentials at the interface have been determined at various polymer concentrations by the spin probe and electrophoresis methods. The average dielectric permeability and density of polymer segments in We adsorption layer have been determined by ESR. The lower boundary of the hydrodynamic thickness of the polymer adsorption layer at the interface has been estimated from the dependences of o and on the ionic strength.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1653–1661, July, 1996. 相似文献
15.
16.
The molecular orientation distribution function of a stable radical 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl in magnetic-field oriented 4-cyano-4’-n-pentylbiphenyl was determined from the angular dependence of the ESR spectra. The preferred molecular orientation of radical species in the liquid crystal matrix was determined. The temperature evolution of the orientation distribution function was studied.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 190–195, January, 2005. 相似文献
17.
B. L. Tumanskii V. V. Bashilov N. N. Bubnov S. P. Solodovnikov V. I. Sokolov 《Russian Chemical Bulletin》1994,43(5):884-886
Using ESR spectroscopy, the reaction of P(O)(OPri)2 phosphoryl radicals with C60ML2 (M=Pd, Pt) was studied and the spin-adducts formed were shown to be unstable under the reaction conditions. The 5-addition of Pt(PPh3)4 to the dimer of phosphorylfullerenyl radicals results in metal-containing dimers (RO)2(O)PL2MC60-C60ML2P(O)(OR)2, which dissociate when exposed to visible light to afford C60ML2P(O)(OR)2 radicals; ML2 in these complexes is located in different positions in relation to the radical center. As a result, the ESR spectra contain the superposition of at least five signals of radicals that differ in HFS constants andg-factors.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 938–940, May, 1994.The present work was supported by the Russian Foundation for Basic Research (Projects 93-03-18725 and 93-03-4101). 相似文献
18.
J. C. Evans K. R. N. Rao S. K. Jackson C. C. Rowlands M. D. Barratt 《Journal of separation science》1985,8(12):829-830
Radicals generated in linoleic acid and deuterated linoleic acid have been trapped by the spin trap 2-methyl-2-nitroso-propane (MNP) and identified by electron spin resonance (ESR) and ENDOR spectroscopy. The formation of two distinct secondary alkyl radical adducts (one conjugated, the other non-conjugated, as shown by their UV absorption spectra) was demonstrated by 11, 11-dideuterio-9-cis-12-cis-linoleic acid using HPLC and ESR spectroscopy. 相似文献
19.
P. V
orek P. indel E. ernokov J. Hole
ek 《Journal of polymer science. Part A, Polymer chemistry》1993,31(12):2923-2928
The ternary catalyst systems based on activated silica, aluminum alkyl, and titanium tetrachloride were polymerized in an ethylene gas-phase polymerization process, and further studied using ESR spectroscopy. Two types of titanium (III) ESR-active centers were observed and a linear dependence between the concentration of that characterized by a rhombic anisotropic signal with g1 = 1.962, g2 = 1.945, and g3 = 1.913 values and catalyst productivity was found. © 1993 John Wiley & Sons, Inc. 相似文献
20.
应用核磁共振和电子自旋共振技术研究了铜锌超氧化物歧化酶(CuZnSOD)的金属重组酶与水溶液中游离组氨酸(His)的相互作用。发现在水溶液中CuZnSOD的金属重组酶活性中心的金属可与加入的His发生作用而被部分地诱导出来,与His形成络合物。 相似文献