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91.
92.
The temperature shift of the neutrino mass in a constant magnetic field is calculated within the framework of the Weinberg-Salam model. The cases of weak field and low and high temperatures are considered. The contribution to the anomalous magnetic moment of the neutrino is determined. The imaginary component of the mass correction describing the reaction of decay and W-boson formation is analyzed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 3–6, December, 1987. 相似文献
93.
A. A. Él’nazarov 《Ukrainian Mathematical Journal》1997,49(12):1938-1944
We establish necesary and sufficient conditions for the exponential diehetemy with matrix projeseters of a countable system of differential equations with quasiperiodic coefficients. 相似文献
94.
95.
SHUbarICHI NOSÉ 《Molecular physics》2013,111(1):191-198
A molecular dynamics simulation method which can generate configurations belonging to the canonical (T, V, N) ensemble or the constant temperature constant pressure (T, P, N) ensemble, is proposed. The physical system of interest consists of N particles (f degrees of freedom), to which an external, macroscopic variable and its conjugate momentum are added. This device allows the total energy of the physical system to fluctuate. The equilibrium distribution of the energy coincides with the canonical distribution both in momentum and in coordinate space. The method is tested for an atomic fluid (Ar) and works well. 相似文献
96.
We justify the averaging method for systems with delay described by both slow and fast variables. The results obtained are applied to the analysis of one problem in control theory. 相似文献
97.
N. M. Nagy J. Kónya M. Földvári P. Kovács-Pálffy 《Czechoslovak Journal of Physics》2003,53(1):A103-A111
The adsorption of cesium was studied on the surface of bentonite rocks from the Carpathian basin. The adsorbed quantity at carrier-free concentration was measured using 137Cs, the adsorption capacity of bentonites for cesium ions was determined by X-ray fluorescence analysis. The relation of the cesium adsorption and mineral composition as well as the structural modifications of crystal structure was studied by X-ray diffraction spectrometry and thermoanalysis. The results show that the adsorbed quantity of cesium primarily depends on the montmorillonite content of bentonites. 相似文献
98.
Attila Nagy 《Semigroup Forum》2014,89(2):475-478
A semigroup S is called a weakly commutative semigroup if, for every a,b∈S, there is a positive integer n such that (ab) n ∈Sa∩bS. A semigroup S is called archimedean if, for every a,b∈S, there are positive integers m and n such that a n ∈SbS and b m ∈SaS. It is known that every weakly commutative semigroup is a semilattice of weakly commutative archimedean semigroups. A semigroup S is called a weakly separative semigroup if, for every a,b∈S, the assumption a 2=ab=b 2 implies a=b. In this paper we show that a weakly commutative semigroup is weakly separative if and only if its archimedean components are weakly cancellative. This result is a generalization of Theorem 4.16 of Clifford and Preston (The Algebraic Theory of Semigroups, Am. Math. Soc., Providence, 1961). 相似文献
99.
H. Spiering V. Ksenofontov O. Leupold J. Kusz L. Deák Z. Németh C. Bogdán L. Bottyán D. L. Nagy 《Hyperfine Interactions》2016,237(1):58
The effect of selfabsorption in Mössbauer sources is studied in detail. Spectra were measured using an old 57 C o/R h source of 74M B q activity with an original activity of ca. 3.7G B q and a 0.15G B q 57 C o/α ? F e source magnetized by an in-plane magnetic field of 0.2 T. The 57 C o/α ? F e source of a thickness of 25 μ was used both from the active and the inactive side giving cause to very different selfabsorption effects. The absorber was a single crystal of ferrous ammonium sulphate hexahydrate (FAS). Its absorption properties were taken over from a detailed study (Bull et al., Hyperfine Interact. 94(1–3), 1; Spiering et al. 2). FAS (space group P21/c) crystallizes as flat plates containing the (\(\overline {2}\)01) plane. The γ-direction was orthogonal to the crystal plate. The 57 C o atoms of the 57 C o/R h source were assumed to be homogeneously distributed over a 6μ thick Rh foil and to follow a one dimensional diffusion profile in the 25 μ Fe-foil. The diffusion length was fitted to 10 μ. The theory follows the Blume-Kistner equations for forward scattering (Blume and Kistner, Phys. Rev. 171, 417, 3) by integrating over the source sampled up to 128 layers. 相似文献
100.
Sam V. Nablo James C. Wood Jr. Marc F. Desrosiers Vitaly Yu. Nagy 《Radiation Physics and Chemistry》1998,52(1-6):479-485
A small capacity (100 g.s−1) pilot system is described for presentation of powders and fine aggregates at high velocity, to an electron beam. Electron beam dose rate is continuously monitored in real time, while the thickness of the fluidized bed used to pneumatically transport the product can be monitored and controlled using beta-gauge techniques. Using electron paramagnetic resonance (EPR) techniques, alanine power mixed with the product is used for precise determination of dose delivered to the powder stream. Thin film dosimeters transported in the bed are also used for dose determination. Results with a variety of products are presented using both dose rate and velocity as the independent variables. Lethality data for the bioburdens present in several powdered foodstuffs are discussed. 相似文献