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121.
V. M. Krymov A. V. Denisov M. I. Sallum S. I. Bakholdin V. M. Mamedov V. S. Yuferev A. A. Rusanov P. V. Smirnov 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(10):1355-1359
The influence of different heat shielding constructions on the distribution of temperature and thermoelastic and residual
stresses in growing basal-plane-faceted sapphire ribbons (Al2O3) is studied. It is shown that inclined shields decrease thermoelastic stresses owing to the redistribution of heat fluxes
from a heater to a ribbon, which allows growing block-free basal-plane-faceted sapphire ribbons. 相似文献
122.
The objective of this work was to obtain a simpler and more accurate analytical expression to determine the Debye–Waller factor of crystals using an n-dimensional Debye approximation involving binomial coefficients and incomplete gamma functions. The results obtained were compared with the corresponding experimental and theoretical results and, the calculated values were shown to be in excellent agreement with those obtained in the experimental and other previous studies. 相似文献
123.
Sh.M. Aliev I.K. Kamilov M.M. Guseynov M.Sh. Aliev V.V. Mamedov Sh.M. Ismailov 《Journal of magnetism and magnetic materials》2009,321(2):74-76
This paper presents methods that can be used in order to determine the relative remanent magnetization and uniaxial magnetic anisotropy constant of particles in powder-based permanent magnets using Mössbauer spectroscopy. The methods were verified on the permanent magnet barium ferrite. 相似文献
124.
V. A. Mamedov N. A. Zhukova T. N. Beschastnova A. T. Gubaidullin Ya. A. Levin I. A. Litvinov 《Russian Chemical Bulletin》2009,58(1):191-202
The condensation of 4-hydroxy-3,5-diphenyl-2-phenyliminothiazolidine with 4,5-dimethyl-1,2-phenylenediamine affords 7,8-dimethyl-3-phenyl-1-phenyliminothiazolo[3,4-a]quinox-alin-4(5 H)- one; the condensation with 1,2-phenylenediamines containing different substituents at positions 4 and 5 gives both theoretically
possible isomeric thiazolo[3,4-a]quinoxalines, which differ in the distribution of these substituents between positions 7 and 8 in the benzene ring of the
quinoxaline system. 3a-Hydroxy-7,8-dimethyl-3-phenyl-l-phenylimino-3,3a-di-hydrothiazolo[3,4-a]quinoxalin4(5 H)- one was isolated and characterized as the intermediate of the reaction giving rise to thiazolo[3,4-a]quinoxaline from 4,5-dimethyl-1,2-phenylene-diamine. This intermediate is a covalent hydrate of the final product. 相似文献
125.
Mamedov V. A. Kalinin A. A. Rizvanov I. Kh. Bauer I. Habicher V. D. 《Russian Chemical Bulletin》2009,58(7):1493-1503
A three-step method for the construction of di(imidazo[1,5-a]quinoxalina)-2(1,3)-benza-dithiacycloalkaphanes has been developed, which includes introduction of a haloalkyl group of various
length and nature into 1,3-bis(4(5H)-oxo-3-phenylimidazo[1,5-a]quinoxalin-1-yl)-benzene at the carbamoyl fragment, transformation of the bishalo-substituted compound thus obtained to bisthiol,
and coupling of the latter to a disulfide. 相似文献
126.
A two-step procedure has been developed for the synthesis of 3-alkylquinoxalin-2(1H)-ones from o-phenylenediamine and ethyl 2-oxoalkanoates prepared by the Grignard reaction of diethyl oxalate with alkyl bromides. Analogous reaction with α,ω-dibromoalkanes instead of alkyl bromides leads to the formation of 3,3′-(alkane-α,ω-diyl)di[quinoxalin-2(1H)-ones]. 相似文献
127.
A. G. Kyazym-zade V. M. Salmanov A. G. Guseinov L. G. Gasanova R. M. Mamedov 《Optics and Spectroscopy》2014,116(4):595-598
The nonlinear absorption of light and its temporal evolution in the vicinity of exciton resonance in layered GaSe and InSe crystals under high optical excitation have been experimentally investigated. The decisive factor for the observed temporal dependence of the absorption coefficient and its dependence on the excitation intensity is screening excitons by nonequilibrium-carrier plasma. It is shown that the increase in the transmittance in the absorption-band edge in GaSe with a simultaneous blue shift of the band edge is caused by filling the energy bands under high optical excitation. 相似文献
128.
Guseinov A. G. Mamedov R. M. Bairamova A. I. Javadova M. M. 《Optics and Spectroscopy》2022,130(5):350-354
Optics and Spectroscopy - Photoluminescence spectra have been studied on the naturally formed surface of a layered Cu3-In5S9 crystal when excited by nanosecond laser radiation. At relatively low... 相似文献
129.
Abdullaev N. A. Amiraslanov I. R. Aliev Z. S. Jahangirli Z. A. Sklyadneva I. Yu. Alizade E. G. Aliyeva Y. N. Otrokov M. M. Zverev V. N. Mamedov N. T. Chulkov E. V. 《JETP Letters》2022,115(12):749-756
JETP Letters - This work is devoted to the experimental study and symmetry analysis of the Raman-active vibration modes in MnBi2Te4·n(Bi2Te3) van der Waals topological insulators, where n is... 相似文献
130.
R.?S.?MadatovEmail author A.?I.?Nadzhafov V.?S.?Mamedov M.?A.?Mamedov 《Russian Physics Journal》2012,54(10):1156-1159
The anisotropy of electrical conductivity in hexagonal TlInS2 crystals irradiated by γ-quanta is investigated. It is established that irradiation by low doses (~50 krad) gives rise to
accumulation of radiation defects both in the tetrahedral space and in the layer plane. As a result, there is an increase
in electrical conductivities σ⊥C and σ∥C. As the dose is increased (above 200 krad), more complex defects are formed due to interaction of the radiation defects with
the inhomogeneities, thus reducing the increase of electrical conductivity in both directions. 相似文献