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791.
We give estimates of quark masses from a comparison of two methods of regularizing the coefficient of the Schwinger term. The masses of the first radial excited states of ?, ω, and ? would have to be slightly higher than indicated by the new Orsay data for this method to yield real solutions for the masses of theu, d, ands quarks. 相似文献
792.
A method for calculating the Landau levels of symmetric p-type inversion layers is presented. Using the envelope function approach in the Hartree approximation the magnetic field is incorporated into the Hamiltonian. In order to characterize the energy levels and to obtain a detailed understanding of the unusual Landau scheme, an analysis of the wave functions is made. Special effects are discussed for the inversion layers adjacent to the grain boundary of a Ge-bicrystal, with two occupied subbands. The simulation of Shubnikov-de Haas data by a density of states analysis shows that the different oscillatory periods are not directly related to the subband occupations. 相似文献
793.
É. Kh. Absalyamova Yu. I. Kol'tsov N. P. Matshina E. A. Nesmelov N. N. Soboleva 《Journal of Applied Spectroscopy》1991,54(1):79-83
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 1, pp. 103–107, January, 1991. 相似文献
794.
E. A. Efimova 《Journal of Mathematical Sciences》1991,53(6):632-644
We consider the relationship between the convergence of the distribution functions of sums of independent random variables and the asymptotic distribution of order statistics.Translated from Statisticheskie Metody Otsenivaniya i Proverki Gipotez, pp. 128–144, 1986. 相似文献
795.
796.
Professor E. M. Bolger 《International Journal of Game Theory》1989,18(1):37-44
Myerson (1977) derived an efficient value for games in partition function form. In this paper, we present a set of axioms which characterize a different efficient value for such games. This latter value assigns value 0 to dummies and assigns nonnegative values to players in monotone simple games. 相似文献
797.
798.
A.V. Eremin E.V. Gurentsov M. Hofmann B.F. Kock C. Schulz 《Applied physics. B, Lasers and optics》2006,83(3):449-454
Time-resolved laser-induced incandescence (TR-LII) was applied for the determination of particle sizes during carbon-particle formation from supersaturated atomic carbon vapor that was generated by laser photolysis of carbon suboxide (C3O2) at room temperature. Thus, the solid carbon particles were formed under hydrogen-free conditions. The TR-LII technique was used for in situ size measurement of growing carbon particles and samples of final particles were analyzed by transmission electron microscopy (TEM). It was found that the particles grow to a final size of 4–12 nm within 0.02–1 ms. The properties of the obtained particles depend on the initial conditions in the reaction volume, i.e. concentration of carbon suboxide, pressure and type of gas diluter, photolysis wavelength, and laser pulse energy. The comparison of TR-LII and TEM particle sizing results yields information about the effective thermal energy accommodation coefficients for He, Ar, CO, and C3O2 molecules on carbon particles. PACS 61.46.Df; 07.60.-j; 78.70.-g 相似文献
799.
Modification of shungite with polyamines, followed by corss-linking with epoxy compounds, yielded chemically and thermally stable polyfunctional anion exchangers. The effect of the nature of a polyamine and epoxy compounds and of the carbon content of shungites and the process conditions on the ion-exchange properties of the samples obtained was studied. 相似文献
800.
Stefanie M. Walz Thomas E. Malner Ulrich Mueller Rolf Muelhaupt 《Journal of Polymer Science.Polymer Physics》2003,41(4):360-367
We explored phase separation and self‐assembly of perfluoroalkyl segments at the surface of polymer films obtained from latices of semifluorinated acrylate copolymers and the corresponding latex blends of nonfluorinated and semifluorinated polyacrylates. With laser‐induced secondary mass spectrometry the fluorine distribution was measured after annealing above the minimum film‐forming temperature of the polymers up to a depth of several micrometers. Depth profiles of a semifluorinated acrylate homopolymer and latex blends thereof with fluorine‐free alkylacrylates with 25, 50, and 75 mol % semifluorinated acrylate as well as a copolymer comprised of alkyl acrylate and semifluorinated acrylate (50/50 mol %) were investigated. In the case of latex blends containing both semifluorinated polyacrylates and fluorine‐free or low‐fluorine polymers, self‐assembly accounted for enrichment of the perfluoroalkyl segments at the surface. Coatings exhibiting low surface energy and having a substantially reduced total fluorine content were obtained. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 360–367, 2003 相似文献