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71.
Thin triangular blunt-nosed plate in a viscous hypersonic flow 总被引:1,自引:0,他引:1
The effect of a small blunt nose on the hypersonic flow past a thin, high-sweep and high-aspect-ratio plate at small incidence
is investigated. The analysis is made by means of numerical simulation within the framework of the parabolized Navier-Stokes
equations and the Euler equations in combination with approximate methods for calculating the heat transfer. The results are
compared with the data of experiments in which some nontrivial features of the heat flux distributions over the thin plate
surface were revealed. 相似文献
72.
Yu. G. Vlasov S. S. Levichev A. A. Kruchinin 《Russian Journal of Applied Chemistry》2012,85(6):940-944
A new ligand based on two pyrazole cycles linked with each other was synthesized. Its interaction with Cu(II), Ni(II), Co(II), Mn(II), Cr(III), Zn(II), and Cd(II) cations in ethanol was studied by the spectrophotometric method. 相似文献
73.
74.
Based on an analysis of chemical diffusion of mercury in p-Cd
x
Hg1–x
Te:As narrow-band solid solutions, a mechanism for conversion of the conductivity type upon ionic etching is suggested. It is shown that the n–p conversion of the conductivity in this case is due to the formation of a donor complex between arsenic in the Te sublattice and an interstitial Hg atom. Moreover, the electron concentration in the converted layer corresponds to the concentration of the implanted arsenic impurity. The theoretical results are confirmed by the experimental investigation of the electron concentration distribution over the n-layer of a p-Cd
x
Hg1–x
Te:As epistructure converted upon ionic etching. 相似文献
75.
L. S. Klimenko I. A. Os’kina V. M. Vlasov I. Yu. Bagryanskaya Yu. V. Gatilov 《Russian Chemical Bulletin》2007,56(6):1130-1134
New types of phototransformations in the quinone series, viz., photocyclizations of 1-aryloxy-2-azido-9,10-anthraquinone in the presence of phenols, were studied. The photolysis affords
mainly 5H-naphtho[2,3-c]phenoxazine-8,13-diones, in which the nitrogen atom is covalently bound to the phenyl ring of the attached phenol. As a result,
complex polycyclic derivatives of phenoxazines were prepared in high yields in one step.
Dedicated to the memory of Academician N. N. Vorozhtsov on the 100th anniversary of his birth.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1089–1093, June, 2007. 相似文献
76.
77.
A. M. Rozen V. S. Vlasov V. I. Marchenko V. N. Rubisov 《Journal of Radioanalytical and Nuclear Chemistry》1990,143(2):357-364
Progress is reviewed in the authors' works on actinide extraction equilibria (including activity coefficient evaluation from extraction data) and their mathematical modelling (including Tc influence on Pu/U separation). 相似文献
78.
G. S. Aravin P. A. Vlasov Yu. K. Karasevich E. V. Makolkin V. A. Polyanskii 《Fluid Dynamics》1987,22(6):920-924
A method is proposed for investigating a chemically reacting plasma by means of an electric probe whose potential is modulated by a high-frequency sinusoidal voltage. The method is based on the use of a numerical solution of the problem of an electric probe introduced under negative potential into a steady-state low-temperature plasma formed in a mixture of chemically reacting molecular gases. The conditions under which the charged particle concentration in the region undisturbed by the probe is constant as a result of equilibrium between the ionization and recombination rates are examined.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 6, pp. 114–119, November–December, 1987. 相似文献
79.
A very large diversity space of synthetically accessible compounds for use with drug design programs
Nikitin S Zaitseva N Demina O Solovieva V Mazin E Mikhalev S Smolov M Rubinov A Vlasov P Lepikhin D Khachko D Fokin V Queen C Zosimov V 《Journal of computer-aided molecular design》2005,19(1):47-63
We have constructed a very large virtual diversity space containing more than 1013 chemical compounds. The diversity space is built from about 400 combinatorial libraries, which have been expanded by choosing sizeable collections of suitable R-groups that can be attached to each link point of their scaffolds. These R-group collections have been created by selecting reagents that have drug-like properties from catalogs of available chemicals. As members of known combinatorial libraries, the compounds in the diversity space are in general synthetically accessible and useful as potential drug leads. Hence, the diversity space can be used as a vast source of compounds by a de novo drug design program. For example, we have used such a program to generate inhibitors of HIV integrase enzyme that exhibited activity in the micromolar range. 相似文献
80.
S. Levitchev A. Smirnova A. Bratov Y. Vlasov 《Fresenius' Journal of Analytical Chemistry》1998,361(3):252-254
The development of ion-selective electrodes with inner solid contact is described using photocurable acrylated polyurethane
matrices and electron-ion exchanger (EI), which provides a reversible transition from electrical conductivity in the metal
to ionic conductivity in the membrane phase. The application of a photocurable polymer matrix gives the possibility to use
modern photolithographic techniques for the formation of all-solid-state chemical sensors. The influence of the polymer matrix
and of the preparation of the membrane on the electro-chemical properties of calcium-selective membrane sensors is shown.
For carbonate-selective membranes the possibility of improvement of electrochemical characteristics by incorporation of the
anionic additive tetrakis (4-chlorophenyl) borate was studied.
Received: 14 June 1997 / Revised: 23 September 1997 / Accepted: 9 October 1997 相似文献