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61.
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   
62.
Rapidity correlations in 800 GeV proton interactions with emulsion nuclei are investigated for different targets and multiplicity regions. To study the energy dependence, the results have been compared with proton interactions at 200 GeV and 400 GeV. A common feature of all the interactions is the existence of strong, short-range correlations. However, no dependence of cluster parameters on primary energy or target mass is found. A marginal increase of correlation strength with multiplicity is observed. Received: 30 March 2001 / Accepted: 18 September 2001  相似文献   
63.
We investigate a standard model for bistable reaction-diffusion-systems, which shares characteristic properties with the van-der-Pol oscillator for distributed generators and the FitzHugh-Nagumo system. In this system we study the effect of a long ranging inhibitor. As a main result we show the existence of two inhomogeneous stationary solutions—the smaller one is always a saddle which corresponds to a critical nucleus, while the larger one arises as astable solution. In carrying out the linear stability analysis for these solutions, we have to treat the Schrödinger-equation for a double-well potential. This is done approximately by a supersymmetric approach which yields the eigenvalues and eigenfunctions of the Schrödinger-equation. Furthermore we compare our analytical findings with numerical results-especially the occurrence of oscillating solutions is shown.  相似文献   
64.
Deep-Level Transient Spectroscopy (DLTS) measurements were carried out on silicon p+nn+ diodes before and after irradiation with fast neutrons at room temperature with fluences 5.5×1011 and 1.0×1012 n/cm2. It was found out, that all preexisting defects decreased their amplitudes during irradiation, while only one defect, identified as a single-charged divacancy, increased in amplitude. An interpretation is proposed in terms of the cluster model, and the applicability of the DLTS is discussed.  相似文献   
65.
A distributed feedback fiber laser made of highly Er-Yb codoped phosphate glass fiber has been demonstrated experimentally. Efficient pump absorption allows for multimode pumping into the cladding of the active fiber. Output powers up to 160 mW have been achieved. The 35 mm long fiber laser device emits with >50 dB side mode suppression ratio.  相似文献   
66.
The need for a highly efficient numerical simulation platform for designing photonic band gap (PBG) structures is outlined in the context of various functional device topologies. In this paper we therefore introduce the Method of Auxiliary Sources (MAS) as a semi-analytical, frequency-domain method for computational optics, which has already proven its accuracy and efficiency in various other fields of electrodynamics. The proposed software package provides an easy-to-handle approach to full-wave analysis of two-dimensional (2D) PBG circuits, PBG-based antennas as well as to dense-integrated optics components that contain optical waveguides, scatterers, resonators and other functional elements. Experimental verifications of the numerical results have been conducted along large-scale prototypes in the microwave frequency range for several device topologies.  相似文献   
67.
Research on Chemical Intermediates - MgO-supported Ni catalysts were selectively catalysed by the hydrogenation of benzonitrile to benzylamine in continuous flow at atmospheric pressure without any...  相似文献   
68.
69.
Russian Journal of General Chemistry - A series of novel benzofuran-1,2,3-triazole hybrid molecules are synthesized using the click chemistry approach. Structures of the synthesized compounds were...  相似文献   
70.
A simple classical model [5] that is based on a blocking of magnetic clusters in a uniaxial anisotropy field explains characteristic properties of magnetization processes of Cu(5–15 at.%) Mn as transition states between the “zero point magnetization” M0 = M(T → OK) and the thermal equilibrium magnetization M = M(t → ∞, T). Further it shows two facts the experimental confirmations of which we report in this paper: (a) a magnetization decrease with increasing temperature in high fields and (b) a superposition rule for the magnetization processes in small fields and at low temperatures.  相似文献   
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