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41.
A short review of the fundamental investigations in the fields of synthesis, properties and application of alumoxanes for the last thirties years is given. 相似文献
42.
Ishchenko A. N. Afanas’eva S. A. Belov N. N. Burkin V. V. Zakharov V. M. Zykova A. I. Sammel’ A. Yu. Skosyrskii A. B. Stepanov E. Yu. Tabachenko A. N. Chupashev A. V. Ushakova O. V. Khabibullin M. V. Yugov N. T. 《Technical Physics》2020,65(6):925-934
Technical Physics - The ballistic resistance of a combined cermet material based on a high-hardness ceramic bound with an intermetallide on a high-strength metal substrate, (TiB2 + NiTi) + Ti, is... 相似文献
43.
Subbotin M. L. Gostev A. A. Anashkin I. O. Belov A. M. Levin I. V. Kolbasov B. N. Kolesnikova E. A. Kravchuk V. L. Maltsev S. G. Nikolaev A. V. Filimonova E. A. 《Physics of Atomic Nuclei》2020,83(7):1131-1144
Physics of Atomic Nuclei - The Ignitor tokamak nuclear fusion research project is one of the most ambitious initiatives undertaken under the long-term scientific cooperation program between the... 相似文献
44.
A. Ya. Belov 《Journal of Mathematical Sciences》2009,156(2):219-260
This review paper is devoted to some questions related to investigations of bases in PI-algebras. The central point is generalization
and refinement of the Shirshov height theorem, of the Amitsur–Shestakov hypothesis, and of the independence theorem. The paper
is mainly inspired by the fact that these topics shed some light on the analogy between structure theory and constructive
combinatorial reasoning related to the “microlevel,” to relations in algebras and straightforward calculations. Together with
the representation theory of monomial algebras, height and independence theorems are closely connected with combinatorics
of words and of normal forms, as well as with properties of primary algebras and with combinatorics of matrix units. Another
aim of this paper is an attempt to create a kind of symbolic calculus of operators defined on records of transformations.
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 13, No. 5, pp. 19–79, 2007. 相似文献
45.
Y. A. Aleksandrov E. I. Tsyganova V. M. Shekunova I. I. Didenkulova I. A. Pishchurova D. E. Belov 《Russian Journal of General Chemistry》2010,80(4):742-748
Catalytic pyrolysis of propane-butane hydrocarbon mixture on the composite ceramic materials with the surface modified with
zinc-, cadmium- phosphorus- and silicon-containing compounds in an open system was studied in the temperature range 500–850°C,
at the rate of the gas mixture flow 20–200 ml min−1, contact duration 0.75–155 s, and the values of the heterogeneity factor 2.0 to 2.9×105 cm−1. The catalytic activity of the systems under similar conditions was compared, the influence of various factors on the yield
of ethylene and propylene was investigated and the sooting was estimated. 相似文献
46.
G. M. Belov D. S. Belov A. V. Kurkin M. A. Yurovskaya 《Chemistry of Heterocyclic Compounds》2012,48(1):73-81
An effective method for the stereoselective synthesis of various nitrogen-containing heterocycles by palladium-catalyzed carboamination
is discussed. The method application examples to the synthesis of natural structures are presented. 相似文献
47.
48.
V. V. Fimushkin A. S. Belov A. D. Kovalenko L. V. Kutuzova Yu. V. Prokofichev S. S. Shimanskiy V. P. Vadeev 《The European physical journal. Special topics》2008,162(1):275-280
The proposed project assumes the development of a universal high-intensity source of polarized deuterons (protons) using a
charge-exchange plasma ionizer. The design output current of the source will be up to 10mA for ↑ D+(↑ H+) and polarization will be up to 90% of the maximal vector (±1) and tensor (+1,−2) polarization. The project is based on the
equipment which was supplied within the framework of an agreement between JINR and IUCF (Bloomington, USA). The project will
be realized in close cooperation with INR (Moscow, Russia). The source will be installed in the linac hall (LU-20) and polarization
of beams will be measured at the output of LU-20. The main purpose of the project is to increase the intensity of the accelerated
polarized beams at the JINR Accelerator Complex up to 1010 d/pulse. Calculations and first accelerator runs have shown that the depolarization resonances are absent for the deuteron
beam in the entire energy range of the NUCLOTRON. The source could be transformed into a source of polarized negative ions
if necessary. The period of reliable operation without participation of the personnel should be within 1000 hours. The project
should be implemented within two to two and a half years from the start of funding. 相似文献
49.
Fairly general conditions on the coefficients
of even and odd trigonometric Fourier series under which L-convergence (boundedness) of partial sums of the series is equivalent to the relation
are given. 相似文献
50.
E. P. Nabirkina T. I. Ignat'eva O. A. Raevskii Yu. P. Belov 《Russian Chemical Bulletin》1989,38(11):2278-2281
Ternary mixed-ligand complexes of divalent copper, where one ligand is an -aminoalkylphosphonic acid (APA) and the second ligand is L-phenylalanine, L-tyrosine, or L-dihydroxyphenylalanine, are studied by potentiometric titration in aqueous medium at 25°C and =0.1. A maximum in the formation of the ternary complexes is exhibited at pH 7–8. The log Kst for the complexes formed and the statistical parameters characterizing the ternary complexes logK and logX are determined. The effect of substituents on the -carbon atom of the -APA and of hydroxy groups on the phenyl substituent of the -amino acids on the nature of the distribution of the complexes formed is studied.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2482–2486, November 1989.The authors thank V. P. Solov'ev for helpful discussions. 相似文献