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161.
162.
Summary High-purity indium was analysed by spark source mass spectrometry, using electrical and photoplate detection. For the calibration of the differences in elemental sensitivity, a standard sample was prepared in which 10 impurities were determined by graphite furnace atomic absorption spectrometry. In this way accuracies of less than 40% were obtained for relatively homogeneous elements at ppm and sub-ppm level. About 40 elements could be determined with detection limits of 10 to 30 ppb. Two pattern recognition methods, principal component analysis and clustering analysis, were applied to obtain information on trace element distribution, which indicated that a number of elements were strongly spatially correlated in the analysed sample.
On leave from: Department of Chemistry, Nanjing Normal University, Nanjing, People's Republic of China 相似文献
Chemische Analyse und Verteilungsbestimmung von Spurenelementen in Indium-Matrix durch Funkenquellen-Massenspektrometrie
On leave from: Department of Chemistry, Nanjing Normal University, Nanjing, People's Republic of China 相似文献
163.
Agrachev A. A. Gamkrelidze R. V. 《Proceedings of the Steklov Institute of Mathematics》2006,253(1):S4-S12
Proceedings of the Steklov Institute of Mathematics - 相似文献
164.
165.
T. Yu. Gumerov A. F. Dobrynina R. A. Yusupov V. P. Barabanov 《Russian Journal of Applied Chemistry》2006,79(12):1935-1939
The behavior of real disperse systems with organic impurities was examined under conditions of destabilization by inorganic coagulants. A number of physicochemical methods of analysis and a simulation method were used to identify the character and type of the complexes formed and to calculate their stability constants. 相似文献
166.
P. V. Dvornikov 《Russian Physics Journal》2006,49(4):392-401
A standard model Lagrangian is constructed making the pseudo-Finsleroid generalization of the Yang-Mills field equation by
the conformal method. The Higgs field potential is suggested that ensures generation of particle masses caused by the spontaneous
symmetry breaking. After transition to the conformal coordinates, the expressions obtained assume the standard form that in
many cases allows the results of pseudo-Euclidean theory to be used in calculations of the Feynman diagrams.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 44–51, April, 2006. 相似文献
167.
168.
V. B. Philippov N. Ya. Kirpichnikova A. S. Kirpichnikova 《Journal of Mathematical Sciences》2003,117(2):4028-4033
The problem on the diffraction of the electromagnetic plane wave on a small obstacle included in a layer is investigated. The obstacle is assumed to be an elliptic cylinder whose diameter and focal distance are small in comparison with the length of the incident wave. It is proved that the small obstacle radiates as a point source, and its amplitude is proportional to the area of the cross-section and the jumps of the dielectric and magnetic constants on the interfaces. Bibliography: 5 titles. 相似文献
169.
A method is developed for a stress analysis in an infinite elastic body containing two neighboring periodically cophasaly curved fibers located along two parallel lines. The stress distribution is studied when the body is loaded at infinity by uniformly distributed normal forces in the fiber direction. The investigation is carried out within the framework of a piecewise homogeneous body model with the use of exact three-dimensional equations of elasticity theory. Numerical results related to the stress distribution considered and the influence of interaction between the fibers on this distribution are given. 相似文献
170.
Salimgareeva V. N. Polevoi R. M. Kolesov S. V. Ostakhov S. S. Ponomareva V. A. Leplyanin G. V. 《Russian Journal of Applied Chemistry》2003,76(5):804-808
The luminescence and scintillation properties of poly(methyl methacrylate) containing 1,1,3-trimethyl-3-phenylindan were studied. 相似文献