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231.
Stepan Yu. Chundak Vukadin M. Leovac Dušanka Ž. Obadović Dragoslav M. Petrović 《Transition Metal Chemistry》1986,11(8):308-312
Summary The hydrazide of 1-naphthylacetic acid forms both bis- and tris-(ligand) high-spin nickel(II) and cobalt(II) complexes possessing an octahedral configuration. The compositions of the complexes are influenced not only by the metal-ligand stoichiometry but also by the nature of the inorganic anion. A physico-chemical investigation showed that the ligand is neutral and bidentate, coordinated through amido-nitrogen and carbonyl oxygen. The compounds were characterized by elemental analysis, magnetic measurements, i.r. and diffuse-reflection spectra and molar conductivity. 相似文献
232.
Stepan G. Mulyarchik Stanislav S. Bielawski Andrew V. Popov 《Journal of computational physics》1994,110(2)
The technique of the initial guess calculation for the conjugate gradient method is proposed. Computational schemes of the linear system solution with symmetrical positive definite matrices are constructed on its basis. Their efficient modifications for systems with five-diagonal matrices are proposed. The investigation of the developed methods using the problem of two-dimensional numerical simulation of bipolar transistors has been carried out. Experimental evidence of the proposed method's efficiency has been obtained. 相似文献
233.
234.
Elinson Michail N. Ryzhkova Yuliya E. Krymov Stepan K. Vereshchagin Anatoly N. Goloveshkin Alexander S. Egorov Mikhail P. 《Monatshefte für Chemie / Chemical Monthly》2020,151(4):567-573
Monatshefte für Chemie - Chemical Monthly - The new electrochemically induced multicomponent assembling was found: the electrocatalytic transformation of benzaldehydes,... 相似文献
235.
We investigate local and semi-local convergence of the combined Newton-Kurchatov method under the classical and generalized Lipschitz conditions for solving nonlinear equations. The convergence order of the method is examined and the uniqueness ball for the solution of the nonlinear equation is proved. Numerical experiments are conducted on test problems. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
236.
Volodymyr Dzhagan Nikolai Mel'nik Olexandra Rayevska Galyna Grozdyuk Viktor Strelchuk Olga Plyashechnik Stepan Kuchmii Mykhailo Valakh 《固体物理学:研究快报》2011,5(7):250-252
Resonant Raman scattering spectra of ultrasmall (<2 nm) magic‐size nanocrystals (NCs) are reported. The spectra of CdS and CdSx Se1‐x NCs, resonantly excited with 325 nm and 442 nm laser lines, correspondingly, reveal broad features in the range of bulk optical phonons. The relatively large width, ~50 cm‐1, and downward shift, ~20 cm‐1, of the Raman bands with respect to the longitudinal optical phonon in bulk crystals and large NCs are discussed based on the breaking of the translational symmetry and bond distortion in these ultrasmall NCs. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
237.
Bayirta V. Egorova Lyubov S. Zamurueva Anastasia D. Zubenko Anna V. Pashanova Artem A. Mitrofanov Anna B. Priselkova Yuri V. Fedorov Alexander L. Trigub Olga A. Fedorova Stepan N. Kalmykov 《Molecules (Basel, Switzerland)》2022,27(10)
A synthetic procedure for the synthesis of azacrown ethers with a combination of pendant arms has been developed and the synthesized ligand, characterized by various techniques, was studied. The prepared benzoazacrown ether with hybrid pendant arms and its complexes with copper and lead cations were studied in terms of biomedical applications. Similarly to a fully acetate analog, the new one binds both cations with close stability constants, despite the decrease in both constants. The calculated geometry of the complexes correlate with the data from X-ray absorption and NMR spectroscopy. Coordination of both cations differs due to the difference between the ionic radii. However, these chelation modes provide effective shielding of cations in both cases, that was shown by the stability of their complexes in the biologically relevant media towards transchelation and transmetallation. 相似文献
238.
Yuriy Azhniuk Vasyl Lopushansky Stepan Hasynets Volodymyr Kryshenik Alexander V. Gomonnai Dietrich R. T. Zahn 《Journal of Raman spectroscopy : JRS》2024,55(5):637-649
Raman spectra of (As1–xBix)2S3 glass samples with x ≤ 0.2 measured at the excitation with above-bandgap (532 nm) laser light at a relatively low power density (Pexc = 4 kW/cm2) clearly confirm the amorphous character, thereby markedly extending the known compositional interval of existence of the (As1–xBix)2S3 glass previously known (x ≤ 0.06). Spectra measured at an increased Pexc (40 kW/cm2) reveal a photostructural transformation in the illuminated area of the glass leading to an additional contribution of Bi–S bonds as well as to an increasing number of cage-type As4S4 units with homopolar As–As bonds. A number of new features in a broad range up to about 1,000 cm−1, which emerge in the Raman spectra of the (As1–xBix)2S3 glasses with high (x ≥ 0.14) Bi content and increase in intensity with the exposure time, are related to a photochemical transformation, namely, oxidation of arsenic and sulphur on the (As1–xBix)2S3 glass surface with formation of units containing arsenate AsO43− and sulphate SO42− ions. These processes are irreversible and occur only in the presence of a sufficient amount of bismuth. 相似文献