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631.
632.
For quasilinear equations div A(x, u, ∇u) = 0 with degeneracy ω(x) of the Muckenhoupt A
p
-class, we prove the Harnack inequality, an estimate for the H?lder norm, and a sufficient criterion for the regularity of
boundary points of the Wiener type.
Translated from Ukrains'kyi Matematychnyi Zhurnal, Vol. 60, No. 7, pp. 918–936, July, 2008. 相似文献
633.
634.
M. A. Nadzhafova A. P. Mamedov Dzh. Dzh. Musaev 《Russian Journal of Applied Chemistry》2008,81(12):2132-2136
The effect of photoirradiation on the luminescent concentrate of heavy gas oil produced by catalytic cracking (>400°C) was examined. 相似文献
635.
636.
Tensors determining and describing the main flow and capacity characteristics of anisotropic media are introduced. A system
of laboratorymeasurements for the determination of the tensors of areal porosity, permeability, limiting gradients, and characteristic
linear dimensions is considered. The pressure dependences of permeability are generalized to take into account the medium
anisotropy. The results of an experiment for the determination of the permeability and limiting (initial) gradient tensors
in band sandstone with orthotropic flow characteristics are presented. The measurements were carried out on four cores: two
along the principal stratification directions, one perpendicular to the stratification, and one inclined at an angle of 45°
to the stratification plane. The latter (fourth) specimen was taken for reference: to test the tensor nature of the introduced
mathematical objects and formulas. The good agreement of the theoretical and experimental results makes it possible to recommend
for engineering calculations both the formulas proposed and the developed method of laboratory investigation of the flow characteristics
of anisotropic reservoirs. 相似文献
637.
M. Balasoiu S. G. Barsov D. Bica L. Vekas S. I. Vorob’ev K. I. Gritsaj V. N. Duginov V. A. Zhukov E. N. Komarov V. P. Koptev S. A. Kotov T. N. Mamedov C. Petrescu G. V. Shcherbakov 《JETP Letters》2008,88(3):210-213
A ferrofluid based on Fe3O4 nanoparticles dispersed in heavy water D2O is studied using the μSR method. The experiment has been carried out at temperatures 26–300 K. It is found that the diamagnetic (muon) fraction is formed in the ferrofluid in about the same amount as in D2O, but the muon-spin relaxation rate in the ferrofluid is much higher than in D2O. A significant shift of the muon-spin precession frequency in the ferrofluid is observed. It is shown that the shift of the muon precession frequency as a function of the external magnetic field is described by the Langevin function typical of paramagnetic magnetization. The mean magnetic field in the medium due to magnetic-nanoparticle polarization in an external field is experimentally determined. The nanoparticle sizes are estimated. 相似文献
638.
Vakhid A. Mamedov Nataliya A. Zhukova Victor V. Syakaev Tat'yana N. Beschastnova Milyausha S. Kadyrova Anastasiya O. Isaeva Sevil V. Mamedova Elena L. Gavrilova Shamil K. Latypov Oleg G. Sinyashin 《Journal of heterocyclic chemistry》2019,56(8):2221-2234
Facile and efficient methods for the synthesis of 3‐benzylquinoxalin‐2(1H)‐ones and thiazolo[3,4‐a]quinoxalin‐4(5H)‐ones by the reaction of the readily available 3‐(α‐chlorobenzyl)quinoxalin‐2(1H)‐ones and thiourea have been developed, with multiple roles of the latter. Possible mechanisms are discussed. These two‐step sequences can be performed in a one‐pot manner to produce the desired products in moderate to high yields. 相似文献
639.
640.
Kh. D. Nagiev D. G. Gambarov P. R. Mamedov F. M. Chyragov 《Journal of Analytical Chemistry》2005,60(5):409-411
Procedures were developed for the photometric determination of tin(II) with pyrogallol azo compounds, 2,3,4-trihydroxyphenylazo-5-sulfonaphthalene (R1) and 2,2,3,4-tetrahydroxy-3-sulfo-5-chlorazobenzene (R2), in the presence of triphenylguanidine and bathophenantroline. The complexation of tin(II) with R1 and R2 was studied. It was found that different-ligand complexes formed in the presence of hydrophobic amines. A bathochromic shift in absorption spectra was observed along with shifts of optimum pH formation. The effect of reagent concentration, time, and temperature on the formation of different-ligand complexes was studied, and their stoichiometry was determined by different methods. It was shown that the determination of tin(II) with R2 in the presence of the third component is highly selective. The developed procedures were used for the photometric determination of tin in Caspian Sea water.__________Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 5, 2005, pp. 468–470.Original Russian Text Copyright © 2005 by Nagiev, Gambarov, Mamedov, Chyragov. 相似文献