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211.
The ideas developed by Gell-Mann and Okubo in studying violation of unitary symmetry are used to describe violation of isototic invariance in strong interactions. The present consideration is performed for the example of the mass spectrum of the octet formed by baryons of spin-parity 1/2+: only for this family are the widths of its particles much less than the scale of the effects being investigated, their masses being known from experiments to a fairly high precision. The Gell-Mann-Okubo formula is generalized in such a way that relations both for the splitting between the isomultiplets of the octet and for the mass splitting within these isomultiplets follow from the new formula. Moreover, a relation between masses that describes their electromagnetic splitting and which coincides in form with the Coleman-Glashow relation also follows from this formula. The relations obtained for the masses of the baryons belonging to the octet in question are satisfied to a precision not poorer than 3%. 相似文献
212.
P. Dimopoulos K. Farakos S. Nicolis 《The European Physical Journal C - Particles and Fields》2002,24(2):287-296
We explore the phase diagram of the five-dimensional anisotropic Abelian Higgs model by Monte Carlo simulations. In particular,
we study the transition between the confining phase and the four-dimensional layered Higgs phase. We find that, in a certain
region of the lattice parameter space, this transition can be first order, and that each layer moves into the Higgs phase
independently of the others (decoupling of layers). As the Higgs couplings vary, we find, using mean field techniques, that
this transition may probably become second order.
Received: 21 December 2001 / Published online: 12 April 2002 相似文献
213.
A cooperative defect-deformation (DD) mechanism is developed for the nucleation of the quasi-monodisperse ensemble of nanoparticles in the low-temperature deposition of Ga atoms in the presence of laser radiation. A comparison with experiment is carried out, and a good agreement between the theoretical and experimental results has been obtained. In particular, in accordance with the DD model, it has been found that the arrangement of nanoparticles is characterized by a latent hexagonal order, and their shape is quasi-hexagonal. It has been shown that the characteristics of the deposited ensemble of nanoparticles can be controlled with the use of an anisotropic deformation. 相似文献
214.
215.
Translated from Programmnoe Oborudovanie i Voprosy Prinyatiya Reshenii, pp. 152–184, 1989. 相似文献
216.
V. K. Mel'nikov 《Communications in Mathematical Physics》1991,137(2):359-381
It is shown that the nonlinear Schroedinger equation with a self-consistent source admits investigation by the inverse scattering method for the Dirac operator. The conditions are found under which the solutions of the nonlinear Schroedinger equation with a self-consistent source describe the creation and annihilation of solitons. 相似文献
217.
218.
J. Pill J. Aufenanger K. Stegmeier F. H. Schmidt D. Müller 《Fresenius' Journal of Analytical Chemistry》1987,327(5-6):558-560
Summary The investigation methods of the action of xenobiotics on sterol biosynthesis from 14C-acetate in rat hepatocyte cultures can be developed, with regard to extraction using Extrelut and the separation of the sterol pattern by thin-layer chromatography, in such a way that they are suitable for wider application, e.g., screening. Good visualisation and recognition of changes in the sterol pattern are possible using autoradiography of the thin-layer chromatogram.
Dedicated to Dr. E. Roesch on occasion of his 65th birthday 相似文献
Dünnschicht-Chromatographie von radioaktiv markiertem Cholesterin und Vorstufen aus biologischem Material. Eine einfache und empfindliche Methode zur Untersuchung einer Beeinflussung des Sterolbiosynthesewegs
Dedicated to Dr. E. Roesch on occasion of his 65th birthday 相似文献
219.
220.
A. V. Boldashevskii Zh. K. Tukhmetova Sh. B. Kasenova S. M. Adekenov A. Nukhuly B. K. Kasenov A. M. Gazaliev S. D. Fazylov 《Russian Journal of Applied Chemistry》2006,79(10):1705-1708
Results of thermochemical studies of a new compound, potassium morpholinodithiocarbamate, are presented. The enthalpies of its solution in water at various dilutions and the specific heat at 173–348 K were examined by the experimental methods of isothermal and dynamic calorimetry. 相似文献