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41.
N. I. Steblevskaya T. B. Emelina M. A. Medkov 《Russian Journal of Inorganic Chemistry》2013,58(8):1009-1013
Yttrium complexation in extraction systems with benzoic acid (BA) and tris(hydroxymethyl)aminomethane (THMAM) was studied. The growth of yttrium distribution ratios in this system is caused by the formation of different-ligand coordination compounds of yttrium with BA and THMAM. Quantum chemical calculations for the formation energy of different-ligand complex showed that the most stable complex forms when yttrium atom coordinates to two THMAM molecules via oxygen and nitrogen atoms and to one THMAM molecule via nitrogen atom. The complex is stable in both bidentate and monodentate coordination of the carboxyl groups of benzoic acid to yttrium atom. Obtained yttrium extracts were used for the synthesis of complex-oxide nanosized cathodophosphors by extraction-pyrolytic technique. 相似文献
42.
Oleg L. Shcheka Nickolay V. Dobrodey Tatyna B. Emelina 《International journal of quantum chemistry》1994,50(3):181-188
Catalysts based on oxides of transition metals were studied by X α–DV calculations. The chemical composition and electronic structure of surface layers for platinum(IV) oxide catalysts modified under percompound electrosynthesis were determined by X-ray photoelectron spectroscopic, quantum chemical, and electrochemical data. The main regularities in electronic structure change under the transition from solid pure oxide PtO2 to its, in part, N-substituted PtO2–xNx were analyzed. Then, we looked for perspective catalysts, calculating the electronic structure for analogous compounds of Ir(III), Ir(IV), Rh(III), and Pd(II). We found that the changes in electronic structure of rhodium oxide under O—N-substitution allowed us to predict the excellent properties of its compound as a catalyst for percompound electrosynthesis reactions. © 1994 John Wiley & Sons, Inc. 相似文献
43.
I. G. Fomina Zh. V. Dobrokhotova M. A. Kiskin G. G. Aleksandrov O. Yu. Proshenkina A. L. Emelina V. N. Ikorskii V. M. Novotortsev I. L. Eremenko 《Russian Chemical Bulletin》2007,56(9):1712-1721
The solid-state thermal decomposition of the tetrabridged dinuclear MnII, FeII, CoII, NiII, and CuII pivalate complexes with apical α-substituted pyridine ligands containing different substituents (2,3-dimethylpyridine or
quinoline) was studied by differential scanning calorimetry and thermogravimetry. The decomposition of the CoII complexes is accompanied by the aggregation to form the volatile octanuclear complex Co8(μ4-O)2(μn-OOCCMe3)12, where n = 2 or 3, whereas the thermolysis of the MnII, FeII, NiII, and CuII complexes is accompanied by the degradation of the starting compounds, the phase composition of the decomposition products
being substantially dependent on the nature of metal and the apical organic ligand.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1650–1659, September, 2007. 相似文献
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45.
Optics and Spectroscopy - The luminescent chemosensor properties of Eu(III) carboxylatodibenzoylmethanates with acetic and acrylic acids as applied to ammonia vapors are studied. Quantitative... 相似文献
46.
Polischuk A. V. Emelina T. B. Cramariuc O. Chukharev V. I. Karaseva T. E. Karasev V. E. 《Russian Journal of General Chemistry》2012,82(2):323-328
The nalidixic acid transient spectra were analyzed and the scheme of photo-conversion of the acid was suggested. At a large
delay of laser pulses the transient absorption spectra contain the bands due to the dissociation of the products of the cation-
and anion-radical photodecomposition in the micro- and millisecond range. By quantum-chemical calculations we revealed that
at the transition to the ion-radical state a proton migration occurs subsequent to the movement of the center of gravity of
the negative charge. The phototransformation of nalidixic was found to proceed with a TICT-effect. 相似文献
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48.
A. V. Polishchuk É. T. Karaseva T. B. Emelina Yu. M. Nikolenko V. E. Karasev 《Journal of Structural Chemistry》2009,50(3):434-438
The X-ray photoelectron spectra (XPS) of the core electrons of the carbon, oxygen, nitrogen, and fluorine atoms of antibiotics from the class of quinolones (nalidixic acid, norfloxacin, and enoxacin), having different antibacterial activities, were measured and interpreted. The integrated intensities of the π-π* and n-π* transition bands in the absorption spectra of the compounds were analyzed. The maxima of the luminescence spectral bands are given along with the lifetimes of the excited states and quantum yields of the protolytic forms of the compounds in aqueous media. The XPS data were compared with the Mulliken charges on heteroatoms obtained by quantum-chemical calculations. 相似文献
49.
Mikhail Bykov Anna Emelina Mikhail Kiskin Aleksei Sidorov Grigory Aleksandrov Artem Bogomyakov Zhanna Dobrokhotova Vladimir Novotortsev Igor Eremenko 《Polyhedron》2009,28(16):3628-3634
The solid-state thermolysis (420–450 °С) of the new heterometallic coordination polymer [Li2Co2(Piv)6(μ-L)2]n (1, Piv is the anion of pivalic acid, L is 2-amino-5-methylpyridine) followed by annealing of the decomposition products at 500 °С was shown to afford LiCoO2 in quantitative yield. Compound 1 was characterized by X-ray diffraction and magnetic measurements. 相似文献
50.
Spectroscopic and Photophysical Properties of Protonated Forms of Some Fluoroquinolones in Solutions
Electronic absorption and fluorescence spectra of ciprofloxacin, norfloxacin, enoxacin, pefloxacin and nalidixic acid in aqueous
solutions were investigated. The time-resolved fluorescence spectra were measured and interpreted. The changes of the luminescence
spectra and electron structure of the compounds under study are explained by different degrees of the spin-orbital interaction
caused by nitrogen heteroatoms lone pairs effect. Possible ways of the protonation process for naphtyridine and quinolone
rings with different substitutions are discussed. The photophysical behavior of FQs was studied using density functional theory
(DFT) calculations. 相似文献