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排序方式: 共有1439条查询结果,搜索用时 7 毫秒
1.
Technical Physics - Analytical models for the magnetization vector field B m in a uniaxial ferromagnetic film are studied. Some of them are found to closely approximate B m even if the quality... 相似文献
2.
A general method for solving the problem of quantization of a top is proposed that allows for finding the Hamiltonian eigenfunctions in the form of polynomials of various degree n in the Cartesian coordinates with the use of the Lamé functions. All three coordinates x, y, and z are equivalently involved in computations, as well as their relations with ellipsoidal coordinates, which makes the computations symmetric. 相似文献
3.
V. S. Antonov V. S. Letokhov A. N. Shibanov 《Applied Physics A: Materials Science & Processing》1981,25(1):71-76
The paper presents the results of studies into ion desorption from the surface of adenine and anthracene molecular crystals
and anthracene molecules adsorbed on a metal as the surface is irradiated by an uv laser at λ=249, 308, and 337 nm. A sharp
increase in molecular ion yield has been revealed with a decrease in radiation wavelength down to 249 nm. At this wavelength
the effect of molecular ion desorption is observed at the radiation intensity of 20∶50 kW/cm2 and pulse duration of 20 ns, it cannot be explained by thermal mechanisms. The initial velocity distribution of photoions
is nonthermal by character, with maximum velocity of 2·105 cm/s in case of adenine. The mechanisms responsible for the effect observed are discussed. 相似文献
4.
5.
N. V. Antonov 《Journal of Mathematical Sciences》1989,47(2):2367-2372
The scaling function is calculated in the framework of the renormalization group approach to the theory of developed turbulence for the velocity correlator to the second order in the -expansion.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 164, pp. 3–9, 1987.The author thanks L. Ts. Adzhemyan, A. N. Vasil'ev, and M. Gnatich for helpful discussions. 相似文献
6.
Alexei Yu. Lukin Sergei V. Shevyakov Alexei V. Laptev Olga I. Davydova Vitali I. Shvets Olga V. Demina Yury P. Strokach Valery A. Barachevsky Michail V. Alfimov Sergei P. Gromov Artem I. Vedernikov Johan Lugtenburg Andrey A. Khodonov 《Journal of inclusion phenomena and macrocyclic chemistry》2004,49(1-2):153-161
An effective synthetic approach to the preparation of a new crown-ether vinylogs involving the Horner–Emmons olefination of carbonyl precursors with the use of C2- and C5-phosphonates was proposed. The effects of the conjugation chain length and the nature of the terminal polar functions in the phosphonate reagent on the yield and process stereoselectivity were discussed. 相似文献
7.
Dmitrieva Z. T. Bondaletov V. G. Antonov I. G. Chernov E. B. 《Russian Journal of Applied Chemistry》2002,75(12):1951-1955
Kinetics of absorption of a mixture of aliphatic, aromatic, and unsaturated hydrocarbons from the gas phase onto polypropylene containing 5, 18, and 40% atactic polymer in its molecular lattice was studied. The kinetic parameters, equilibrium constant, and Gibbs energy of adsorption-desorption of the hydrocarbons were determined by zero-, first-, and second-order optimization of the solution of the multiparameter equation. These parameters were correlated with the adsorbent composition and the number of sorption-desorption cycles. 相似文献
8.
V. V. Kurdakova N. G. Antonov V. V. Malev V. V. Kondrat’ev 《Russian Journal of Electrochemistry》2006,42(4):299-305
The results of a study of poly(3-octylthiophene) films with the aid of an electrochemical quartz microbalance are presented. The effect of the nature of the electrolyte anion on the determined weights of mobile species that are transported through the film/electrolyte interface is discussed. The obtained results point to a substantial role played by the solvent transport in the course of the electrode reaction. The results concerning the influence exerted by the electrode material on the observed regularities are presented. 相似文献
9.
A. A. Kiryushkin V. I. Shchelokov V. K. Antonov Yu. A. Ovchinnikov M. M. Shemyakin 《Chemistry of Natural Compounds》1967,2(4):224-229
Summary 1. A method for the separation and quantitative determination of - and -DNP derivatives of , -DABA, ornithine, and lysine has been proposed.2. A quantitative evaluation of the N N migration in four peptides of , -DABA has been carried out.3. The degree of migration in inactive polymyxin M and the DNP-peptides from a partial hydrolyzate of the inactivated antibiotic has been determined.4. The amino acid composition of the DNP peptide B1 from a partial hydrolyzate of active DNP-polymyxin M has been established.5. The quantitative aspect of the conversion of
and
diketopiperazines has been studied.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 4, pp. 277–284, 1966 相似文献
10.
An approach for quantitative analysis of mixtures with unknown individual responses of the components is discussed. Although it is based on a resolution of overlapping bands technique, the main emphasis is not given to the computational facets of curve fitting. A logical procedure is described, allowing estimation of the unknown concentrations in the mixture, and both the number of overlapping bands and their assignment to the components in the solution to be determined automatically. A general conclusion about the precision of the method cannot be defined, because it depends on the extent of overlapping of the individual spectra of the components and their complexity. Using this procedure a complicated three-component acid-base equilibrium of a halochromic dye in solution is studied. 相似文献