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排序方式: 共有341条查询结果,搜索用时 15 毫秒
281.
282.
Anatolii S. Burlov Valery G. Vlasenko Yurii V. Koshchienko Nadezhda I. Makarova Mikhail A. Kiskin Alexandra A. Kolodina Dmitrii A. Garnovskii Alexander A. Zubenko Yurii D. Drobin Alexander L. Trigub Anatolii V. Metelitsa 《应用有机金属化学》2020,34(1):e5302
A series of Zn(II) complexes of the tridentate azomethine ligands, condensation products of 2-(N-tosylamino)benzaldehyde and 2-aminoalkylpyridines, were synthesized by chemical and electrochemical methods. All compounds were characterized on the basis of C, H, N elemental analysis, Fourier-transform infrared, 1H nuclear magnetic resonance, UV–Vis, and photoluminescence studies. The local atomic structures of complexes were determined from analysis of extended X-ray absorption fine structure and X-ray absorption near-edge structure of Zn K-edges. The molecular structure of chloro-{4-methyl-N-[2-[(Z)-2-pyridyl)ethyliminomethyl]phenyl]benzenesulfamide}zinc(II) was determined by X-ray single-crystal diffraction. The fluorescence spectra show that these complexes in dimethyl sulfoxide solutions at room temperature emit bright blue luminescence at 435–461 nm with fluorescence quantum yields in the range of 0.20–0.31. The assignment and the nature of the bands in experimental UV–Vis spectra of complexes were analyzed using time-dependent density functional theory calculations B3LYP/6-31G(d). The azomethines and complexes of zinc have been screened for their antibacterial, protistocidal, and fungistatic activities against Penicillium italicum, Colpoda steinii, Escherichia coli 078, and Staphylococcus aureus P-209, and the results are compared with the activity of furazolidone, chloroquine, and Fundazol. 相似文献
283.
Burlov A. S. Vlasenko V. G. Lifintseva T. V. Milutka M. S. Koshchienko Yu. V. Uraev A. I. Garnovskii D. A. Rusalev Yu. V. Lazarenko V. A. Khrustalev V. N. 《Russian Journal of Coordination Chemistry》2020,46(7):485-492
Russian Journal of Coordination Chemistry - (4Z)-4-[(2-Diethylaminoethylamino)methylene]-5-methyl-2-phenylpyrazol-3-one (НL, product of the condensation of... 相似文献
284.
A. D. Pomogailo G. I. Dzhardimalieva S. I. Pomogailo N. D. Golubeva G. V. Shilov E. A. Dzhavadyan A. S. Burlov S. A. Mashchenko D. A. Garnovskii 《Russian Chemical Bulletin》2016,65(1):139-150
The controlled thermolysis of mono(NiII, CuII, and CoII) and dinuclear (NiII, CuII, and FeII) chelate complexes with azomethine ligands, containing oxygen, nitrogen, and sulfur atoms in the chelate rings, was studied. The effect of the ligand environment on the thermal stability and composition of the resulting nanocomposites was examined. Comparative thermal analysis (DSC, DTA, and TGA) of the metal chelate complexes was performed. Their thermolysis products were characterized using elemental analysis, X-ray powder diffraction, scanning electron microscopy, and gel permeation chromatography. The magnetic properties of the nanocomposites obtained were analyzed. 相似文献
285.
螺旋桨空化噪声连续谱由大量空泡随机崩溃所辐射噪声叠加而成。据此,考虑到空泡初始崩溃时刻的随机性和各空泡辐射噪声频谱的相似性,对四种情况空化辐射噪声连续谱特性分别进行了理论分析表明,可依据空泡半径和初始崩溃时间的统计性质,采用蒙特卡罗方法对空化噪声连续谱波形进行仿真建模,模型参数为空泡半径期望值、差异度和随机度,分别相应于确定辐射噪声的基准波形、各空泡噪声频谱相似程度和大量空泡的随机崩溃过程。该方法输入参数物理意义明确,控制简单,能较好地仿真空化噪声连续谱的特性,仿真结果与理论分析吻合较好。 相似文献
286.
287.
Lourenc{c}o BEIR~AO DA VEIGA Franco BREZZI FrancoDASSI Luisa Donatella MARINI Alessandro RUSSO 《数学年刊B辑(英文版)》2018,39(2):315-334
The authors study the use of the virtual element method (VEM for short) of order k for general second order elliptic problems with variable coefficients in three space dimensions. Moreover, they investigate numerically also the serendipity version of the VEM and the associated computational gain in terms of degrees of freedom. 相似文献
288.
289.
D. A. Garnovskii A. S. Antsyshkina A. V. Churakov G. G. Sadikov V. S. Sergienko I. S. Vasil’chenko A. I. Uraev V. G. Vlasenko Ya. V. Zubavichus S. I. Levchenkov Yu. V. Revinskii A. S. Burlov 《Russian Journal of Inorganic Chemistry》2014,59(5):431-440
Chemical and electrochemical synthesis of a series of cobalt(II), nickel(II), copper(II), and zinc(II) complexes of tridentate Schiff base (H2L), a product of condensation of N-(2-aminophenyl)-4-methylbenzenesulfonamide (2-tosylaminoaniline) with 1-phenyl-3-methyl-4-formylpyrazol-5-ol was accomplished. The structure and composition of metal-chelates were established by the C, H, N elemental analysis, IR, 1H NMR, EXAFS spectroscopy and magnetochemical data. The structures of all complexes were confirmed by of X-ray crystallography. 相似文献