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1.
The spectrum and the spatial distribution of the emission of scattered particles upon bombardment of Be, Ti, Ta, and W with H and He ions were studied. The quantum yield and the velocity and angular distributions of the scattered excited particles were measured. Computer simulation of the scattering of H ions and He ions from the metals under study was performed with the use of the program TRIM-95. Agreement is observed between the calculated and experimentally measured angular distributions of the scattered particles. 相似文献
2.
N. N. Koval’ Yu. F. Ivanov I. M. Goncharenko O. V. Krysina Yu. A. Kolubaeva K. A. Koshkin 《Russian Physics Journal》2007,50(2):146-152
Phase composition, defect substructure, and mechanical properties of the Ti-Si-N coating deposited on metal and ceramic-metal substrates by electroarc sputtering of the Ti-Si composite cathode in an ionized
nitrogen atmosphere are investigated by the methods of modern materials science. It is established that coatings so formed
with a thickness of ∼1–3 μm are superhard (Hv ∼ 50 GPa), and have the nanocrystalline structure (with crystalline sizes D = 7 nm) based on titanium nitride δ-TiN.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 46–51, February, 2007. 相似文献
3.
V. T. Kalinnikov Zh. A. Ezhova N. A. Zakharov E. M. Koval’ 《Russian Journal of Inorganic Chemistry》2007,52(1):112-115
The CaCl2-(NH4)2HPO4-NH2(CH2)4NH2CHCOOH-NH3-H2O system at 25°C is studied using Tananaev’s solubility (residual concentrations) method and pH measurements. Lysine-containing calcium hydroxylapatite Ca10(PO4)6(OH)1.9[NH2(CH2)4NH2CHCOO]0.1 · 6H2O is identified using chemical analysis, thermogravimetry, powder X-ray diffraction, and IR spectroscopy. 相似文献
4.
A new preparative method of synthesis was developed for unsymmetrical, symmetricaldisulfides consisting in sulfenylation of sodium thiolates with N-arenesulfenyl-N,N'-bis(arenesulfonyl)sulfin-amidines. Imination of unsymmetrical disulfides with sodium chloroamides of sulfonic acids occurs at the more nucleophilic sulfur atom affording N,N'-bis(arenesulfonyl)sulfinamidines and symmetrical disulfides. 相似文献
5.
I. V. Koval’ 《Russian Journal of Organic Chemistry》2005,41(5):631-648
Data on thiols structure, physicochemical characteristics, and synthetic procedures for preparation are systematized and generalized.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 647–664.Original Russian Text Copyright © 2005 by Koval’. 相似文献
6.
E. A. Belousova V. V. Koval N. I. Rechkunova S. Kh. Degtyarev O. S. Fedorova O. I. Lavrik 《Russian Chemical Bulletin》2005,54(5):1306-1310
The interaction of DNA polymerase Tte from Thermus thermophilus B35 with dUTP analog containing a fluorescein residue bound to C(5) of the base (Flu-dUTP) was studied by fluorescence titration.
The dissociation constants of the enzyme—substrate complexes in the absence and in the presence of a DNA duplex containing
an extended template and bivalent metal ions and the kinetic parameters of polymerization by DNA polymerase Tte in the presence of Flu-dUTP were determined.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1268–1272, May, 2005. 相似文献
7.
Natalia V. Loginova Tat’yana V. Koval’chuk Rimma A. Zheldakova Anna A. Chernyavskaya Nikolai P. Osipovich Gennady K. Glushonok Henry I. Polozov Victor L. Sorokin Oleg I. Shadyro 《Central European Journal of Chemistry》2006,4(3):440-457
Cu (II) complexes with the sterically hindered diphenol derivatives 3,5-di(tert-butyl)-1,2-benzenediol (I), 4,6-di(tert-butyl)-1,2,3-benzenetriol (II) and the sulfur-containing 4,6-di(tert-butyl)-3-(2-hydroxyethylsulfanyl)-1,2-benzenediol (III) and 2-[4,6-di(tert-butyl)-2,3-dihydroxyphenylsulfanyl]acetic acid (IV) have been synthesized and characterized by elemental analysis, TG/DTA, FT-IR, ESR, XPS, XPD and conductivity measurements.
Compounds I–III can coordinate in their singly deprotonated forms and act as bidentate ligands. These compounds yield Cu (II) complexes of the stoichiometry Cu(L)2, which have square planar geometry (g| > g⊥ > ge). Unlike them, compound IV behaves as a terdentate ligand, and its complex Cu(LIV)2 has distorted octahedral geometry. According to ESR data, only the Cu(LII)2 complex contains a very small amount of phenoxyl radicals. Antimicrobial activities of these ligands and their respective
Cu (II) complexes have been determined with respect to Gram-positive and Gram-negative bacteria, as well as on yeasts. Their
phytotoxic properties against Chlorella vulgaris 157 were also examined. 相似文献
8.
The molecular structures of 1,3-benzodioxole and 1,3-indandione partially oriented in nematic solvents have been studied by NMR. Results for 1,3-indandione agree well with a planar model. The structural parameters are similar to those obtained by X-ray studies. No keto-enol tautomerism is observed. An anomalous structural result is obtained for 1,3-benzodioxole if the molecule is assumed to be planar. Dipolar couplings agree well with puckered model. The puckering angle is found to be about 15.5° ± 2°, similar to the values observed for TTF, TSeF and 2,5-dihydrofuran. 相似文献
9.
N. V. Stratan E. P. Koval’chuk J. Blazejowski 《Russian Journal of General Chemistry》2004,74(12):1900-1906
In terms of the ability for electrochemical transformations in acidic medium, the reactivity decreases in the order o-aminoacetophenone > p-aminoacetophenone > m-aminoacetophenone > aniline. The products of electrochemical polycondensation of the ortho and para isomers are conductors. Oxidative polycondensation of o-aminoacetophenone forms emeraldin hydrosulfate, and with p- and m-aminoacetophenones, emeraldin and leucoemeraldin are formed. In terms of thermal stability, polyacetoaminophenones can be ranked in the order poly-o-aminoacetophenone > poly-m-aminoacetophenone > poly-p-aminoacetophenone.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 12, 2004, pp. 2012–2018.Original Russian Text Copyright © 2004 by Stratan, Kovalchuk, Blazejowski.This revised version was published online in April 2005 with a corrected cover date. 相似文献
10.
V. Brabec M. Ryšavý O. Dragoun M. Fišer A. Kovalík Cs. Ujhelyi D. Berényi 《Zeitschrift für Physik A Hadrons and Nuclei》1982,306(4):347-351
The relative conversion line intensities of the 35 keV transition in125Te were measured using the 50 cm π√2 iron-yoke magnetic spectrometer. The transition was proved to be ofM1+(8.7±1.5)×10?4 E2 multipolarity, the magnetic component being affected by the nuclear structure with λ=2.4±1.4. The conversion intensity ratio,0/N 1 , was determined to be 0.115+0.005 for both Ag125 I and Cu125 I sources. It is in accordance with previous measurements for the Zn125m Te and Pb125m Te sources and differs from those for the125mTeO2 and Na2H 4 125m TeO6 ones. The conversion coefficients were calculated for 32 configurations of the valence shell of free tellurium atom and ions and were compared with the experimental results. 相似文献