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151.
S. A. Gurevich T. A. Zaraiskaya S. G. Konnikov V. M. Mikushkin S. Yu. Nikonov A. A. Sitnikova S. E. Sysoev V. V. Khorenko V. V. Shnitov Yu. S. Gordeev 《Physics of the Solid State》1997,39(10):1691-1695
The concentration and chemical state of copper in the subsurface region of Cu/SiO2 composite films obtained by simultaneous magnetron sputtering from two sources (Cu and SiO2) are determined by x-ray photoelectron spectroscopy (XPS). It is established that copper in the as-grown film is primarily in the form of unoxidized atoms dispersed in a SiO2 matrix. Annealing of the film results in practically no oxidation, but about 70% of the copper atoms condense into metallic clusters with sizes below 10 Å in the subsurface region and about 50 Å in the bulk of the film. The changes in the binding energy of core electrons, and especially in the energies of Auger electrons, are so large in this situation that photoelectron and Auger spectroscopy are efficient methods for monitoring the chemical state of this composite material. 相似文献
152.
The changes in the magnetization of yttrium iron garnet (YIG) when irradiated by a pulsed neodymium laser beam with wavelength
λ=1.06 μm are investigated. Measurements are performed in the temperature range from 100 K to 600 K in various external magnetic
fields. YIG single crystals grown along the crystallographic (100), (110), and (111) directions are chosen so that the external
anisotropy of the indicated processes can be determined. Characteristic temperature intervals dominated by different mechanisms
of variation of the magnetization under the influence of a laser pulse are discussed.
Fiz. Tverd. Tela (St. Petersburg) 39, 1263–1266 (July 1997) 相似文献
153.
The temporal evolution of a long-pulse high-density electron beam in a high-power traveling-wave tube with a periodic magnetic
focusing system is investigated. The relation between the variation of the characteristics of the electron beam and ionization
of the residual gas and particles desorbed from the electrode surfaces is shown. A strong influence of the formation of the
collector plasma and the flux of ions from its surface on the beam dynamics is revealed. The effect of microwave fields in
the transport channel on the characteristics of the beam during its evolution is studied.
Zh. Tekh. Fiz. 67, 54–58 (December 1997) 相似文献
154.
有势场逆问题的边界元法 总被引:5,自引:0,他引:5
本文给出了位势方程逆问题的一种最小二乘边界元解法。控制方程为Laplace方程,但一部分边界上未给出任何边值,而只在某些内点上给出了势函值。这一问题在数学上属不适定问题,但在一定条件下存在唯一解。本文同时给出了一种估计解的可靠性的方法。数值试验表明,这类逆问题采用边界元法是非常有效的。 相似文献
155.
156.
A simple method is proposed for increasing the accuracy of computation of the eigenvalues of elliptic operators, which does not require high-order accurate schemes.Translated from Vychislitel'naya i Prikladnaya Matematika, No. 63, pp. 63–68, 1987. 相似文献
157.
I. V. Ukrainets S. G. Taran O. V. Gorokhova P. A. Bezuglyi A. V. Turov 《Chemistry of Heterocyclic Compounds》1994,30(2):204-207
In a solution of DMF, 2-carbethoxymethyl-4H-3,1-benzoxazin-4-one reacts with primarily aromatic amines basically with the formation of the corresponding 2-carbethoxymetlzyl-3-arylquinazolin-4(3H)-ones. Possible mechanisms of these chemical transformations are reported and discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 225–228, February, 1994. Original article submitted June 28, 1993. 相似文献
158.
I. M. Karnaukh A. S. Moskovkin G. V. Ponomarev 《Chemistry of Heterocyclic Compounds》1994,30(1):20-25
The mass spectral behavior of 1, 2-di (mesoetioporphyr inyl-1)- and 1, 2-di (mesooctaethylporphyrlnyl) ethanes and ethylenes, their Cu and Ni complexes, as well as Ni Schiff bases of 1, 2-di (mesooctaethylporphyrinyl)ethane complexes, under ionization by electron impact and bombardment by accelerated atoms, was studied. Peaks of molecular ions, for which the basic decomposition pathways were established on the basis of an analysis of the parent and daughter ions, were observed in the electron impact mass spectra of all these compounds.For Communication 29, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 24–29, January, 1994. 相似文献
159.
V. A. Samsonov L. B. Volodarskii V. L. Korolev G. Kh. Khisamutdinov 《Chemistry of Heterocyclic Compounds》1994,30(10):1243-1249
The reaction of 4-aminobenzofurazan with aryldiazonium salts leads to the formation of 4-amino-5-aryl-azobenzofurazans and 5-amino-2-aryl-4-nitroso-2H-benzotriazoles, products of the rearrangement of the initially formed 4-amino-7-(arylazo)benzofurazans. Oxidation of the benzofurazan as well as of the triazole derivatives gives 7-aryl-1,2,3-triazol[4,5-e]benzofurazans. The chemical properties of some of the compounds obtained have been investigated.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1432–1438, October, 1994. Original article submitted July 25, 1994. 相似文献
160.
G. A. Shvekhgeimer 《Chemistry of Heterocyclic Compounds》1994,30(6):633-660
We review literature data on synthesis and conversions of heterocyclic compounds using ultrasonic treatment.We analyze the effect of ultrasound on organic reactions involving participation of heterocyclic compounds.A. N. Kosygin State Technical Academy, Moscow 117918. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 723–755, June 1994. Original article submitted December 22, 1993. 相似文献