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1.
Korobeinikova E. N. Prokhorov I. A. Bezbakh I. Zh. Shul’pina I. L. 《Crystallography Reports》2021,66(3):387-393
Crystallography Reports - The specific features of the formation of concentration inhomogeneities in crystals grown by the Czochralski method (GaSb:Te, Ge:Ga) and by the Bridgman method... 相似文献
2.
The problem of transition radiation generated by relativistic particles incident on atomic strings in a crystal at a small angle is considered. Conditions are obtained under which the problem of transition radiation reduces to that of radiation generated by a collision with a filament-like target. It is shown that the angular distribution of transition radiation is symmetric with respect to the atomic-string axis. 相似文献
3.
V. N. Knyukshto A. M. Shul’ga E. I. Sagun É. I. Zen’kevich 《Optics and Spectroscopy》2006,101(6):895-901
Based on the study of the phosphorescence and phosphorescence excitation spectra of Pd(II) tetramethylporphyrin (PdTMP) and Pd(II) tetramethyldiethylporphyrin (PdTMDEP) in solutions in 2-methyltetrahydrofuran and dodecane in the temperature range 77–283 K, the occurrence of the splitting of the lowest degenerate singlet (S 1) and triplet (T 1, T 2) levels of porphyrin molecules is established. In the absorption of molecules of the compounds studied, two components, S 1 and S 2, are revealed in the range of allowed long-wavelength Q(0,0) transitions (530–550 nm) and four components, T 1–T 4, are observed in the range of spin-forbidden intersystem crossing transitions S 0 → T n (560–670 nm), with all the triplet levels T 1-T 4 being located below the S 1 level on the energy scale. It is shown that an increase in the degree of deformation of the porphyrin macrocycle caused by steric interactions between β alkyls and hydrogen meso atoms is accompanied by an increase in the splitting in the system of singlet levels δE(S 2–S 1) from 120 cm?1 for PdTMDEP to 215 cm?1 for PdTMP, as well as by an increase in the splitting in the system of triplet levels δE(T 2–T 1) from 190 cm?1 for PdTMDEP to 250 cm?1 for PdTMP. 相似文献
4.
5.
S. V. Chernov E. E. Shul’ts M. M. Shakirov I. Yu. Bagryanskaya Yu. V. Gatilov G. A. Tolstikov 《Russian Journal of Organic Chemistry》2005,41(4):535-545
Oxidation of lambertianic acid methyl ester and methyl 15,16-epoxy-17-hydroxylabda-13(16)14-dien-18-oate gave 17-nor-8-oxo-, 8,12-epoxy-17-hydroxy-, and 8-formyl-17-norlabdadienoic acid esters which were subjected to reductive amination, and the subsequent intramolecular aminomethylation of 17-nor-8(R)-methylamino- and 17-methylaminolabdadienoates with formaldehyde afforded new polycyclic compounds, furoazocine and furoazonine derivatives.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 4, 2005, pp. 547–556.Original Russian Text Copyright © 2005 by Chernov, Shul’ts, Shakirov, Bagryanskaya, Gatilov, Tolstikov.For communication VIII, see [1]. 相似文献
6.
B. P. Tarasov V. N. Fokin A. P. Moravskii Yu. M. Shul’ga 《Russian Chemical Bulletin》1997,46(4):649-652
Fullerene hydrides containing 24–26 H atoms per fullerene molecule were obtained by hydrogenation of solid-phase mixtures
of fullerenes with either intermetallic compounds LaNi5, LaNi4.65Mn0.35, CeCo3 or V and Pd metals with gaseous hydrogen at 1.0–2.5 MPa and 573–673 K. These fullerene hydrides decompose at 800 K with evolution
of H2. Upon subsequent heating to 1000 K, vanadium reacts with fullerene to yield a cubic phase of vanadium carbide. The intermetallic
compounds react with fullerene with the formation of a metallic phase of the 3d-metal and destruction of fullerene. Palladium
does not react with fullerene.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 679–683, April, 1997. 相似文献
7.
Eun-Ku Lee Kwang-Deog Jung Oh-Shim Joo Yong-Gun Shul 《Reaction Kinetics and Catalysis Letters》2004,83(1):25-30
The room temperature wet catalytic oxidation was conducted in a batch reactor with V/MgO catalyst. The XRD study of the catalyst
used indicated that V/MgO could not only oxidize H2S to sulfur selectively, but also prevent the sulfidation of metal oxide
effectively at the room temperature. The XPS study indicated that the H2S oxidation with V/MgO could proceed by a redox mechanism
(V5+↔ V4+) and that V3+ formation (V4+→ V3+), was responsible for the deactivation of V/MgO.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
8.
G. N. Boiko Yu. M. Shul’ga O. S. Roshchupkina A. S. Lobach N. F. Gol’dshleger 《Russian Journal of General Chemistry》2007,77(4):625-628
Coordinated fullerene acts as a hydrogen acceptor in reactions with compounds having weakened C-H bonds (1,4-dihydropyridine and 9,10-dihydroanthracene). Metal fullerides are the dehydrogenation catalysts. They activate the C-H bonds of dihydroanthracene and diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate in positions 9,10 and 1,4, respectively. No activation of norbornane carbon-hydrogen bonds with metal fullerides was observed under mild conditions. 相似文献
9.
Enhancing the organic dye adsorption on porous xerogels 总被引:4,自引:0,他引:4
Zhijian Wu Ik-Sung Ahn Chang-Ha Lee Jung-Hyun Kim Yong Gun Shul Kangtaek Lee 《Colloids and surfaces. A, Physicochemical and engineering aspects》2004,240(1-3):157-164
We investigate the adsorption of four different organic dyes (i.e., methyl orange, alizarin red S, brilliant blue FCF, and phenol red) on porous xerogels. To understand the factors affecting the adsorption capacity of the xerogels, we vary the hydrophobicity and the textural properties of the xerogels as well as the solution pH. We control the hydrophobicity by mixing two different precursors (i.e., vinyltriethoxysilane (VTES) and tetraethoxysilane (TEOS)) and the textural properties by using cetyltrimethylammonium bromide (CTAB) as a templating agent. We find that the adsorption capacity is enhanced as the organic/inorganic hybrid xerogel or the templated xerogel is used instead of the purely inorganic or the untemplated xerogel. In all the cases studied, adsorption decreases as the pH is increased due to the electrostatic repulsion between the dyes and the xerogel surface. We find that both the hydrophobic surface and larger pore size/volume are required to enhance the adsorption capacity significantly. 相似文献
10.
Shul"gin V. F. Zlatogorskii S. M. Zub V. Ya. Larin G. M. 《Russian Chemical Bulletin》2002,51(12):2273-2276
The binuclear vanadyl(ii) complexes [(VO)2·2Py·2EtOH]·mH2O with acyldihydrazones of salicylaldehyde (H4L) and dicarboxylic acids were synthesized and studied. In these complexes, two chelate vanadyl(ii) complexes with the tridentate bicyclic ligands are linked to each other by the polymethylene bridges —(CH2)
n
— of different lengths varying from one to four units. The ESR spectra of solutions of these complexes, unlike those of analogous copper(ii) complexes, have an isotropic signal with an eight-line hyperfine structure (g = 1.972, a
V = 93·10–4 cm–1) typical of monomeric vanadyl complexes, which indicates that no exchange interactions occur between the paramagnetic centers through the polymethylene chain. 相似文献