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991.
The (6Li, 7Be) and (6Li, 7Li) reactions on 6Li and 7Li nuclei were investigated in the angular interval 0°–20° in the laboratory system at a 6Li energy of 93 MeV. In addition to low-lying states of the 5,6He and 5,6Li nuclei, broad structures were observed near the t(3He)+d and t(3He)+t thresholds at the excitation energies of 16.75 (3/2+) and ~20 MeV (for 5He), 16.66 (3/2+) and ~20 MeV (5Li), 14.0 and 25 MeV (6He), and ~20 MeV (6Li). The angular distributions measured in the 7Li(6Li, 7Be)6He reaction for transitions to the ground state (0+) and excited states at E x=1.8 MeV (2+) and 14.0 MeV of the 6He nucleus were analyzed by the finite-range distorted-wave method assuming the 1p-and 1s-proton pickup mechanism. The (6Li, 7Be) and (6Li, 7Li) reactions were shown to proceed predominantly through the one-step pickup mechanism, and the broad structures observed at high excitation energies are considered as quasimolecular states of the t(3He)+d and t(3He)+t types.  相似文献   
992.
在酸性条件下,采用乙酸乙酯萃取、Na2HPO4溶液反萃取分离酱汪、食醋中的山梨酸、苯甲酸,卡尔曼滤波法计算结果,并与比值导数波谱法进行比较。结果表明,卡尔曼滤波法较地数波谱法有较高准确度和精密度,并能监测干扰物质存在与否。用于实际样品分析有更高的可靠性。  相似文献   
993.
The asymptotic analysis of the nonlinear vibrations of a charged drop that are induced by a multi-mode initial deformation of its equilibrium shape is performed. It is shown that when two, three, or several neighboring modes are present in the initial deformation spectrum, the mode with the number one (translational mode) appears in the second-order mode spectrum. The excitation of the translational mode follows from the requirement of center-of-mass immobility and causes the dipole components (which are absent in the linear analysis) to appear in the spectra of the acoustic and electromagnetic radiation of the charged drop.  相似文献   
994.
995.
996.
The results of measuring the vertical variability of sound fields are presented for a coastal wedge off the Pacific shelf of the Kamchatka peninsula. It is shown that the vertical radius of sound field correlation can reach ~30 m for frequencies within 600–800 Hz. The scatter of the specific parameters of the variability is in rather wide limits depending on the location of a vertical chain of receiving hydrophones, the hydrological conditions, the azimuth angle of the sound source, and the relief and bottom structure of the coastal wedge.  相似文献   
997.
A change in the spontaneous polarization and the nonlinear susceptibility in H: LiNbO3 waveguides is calculated from experimental data for the shift of the fundamental absorption for variously polarized rays and from IR reflection data in the range of NbO6 octahedron vibrations. It is shown that taking into account the lattice disorder provides good agreement between the theory and experiment.  相似文献   
998.
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   
999.
The problem of the effective conductivity and the distributions of a field and currents is analyzed in a regular two-component system composed of regular triangles. An efficient solution method is developed that admits a generalization to multicomponent systems.  相似文献   
1000.
The photoluminescence spectra of ZnS : Mn plastically deformed single crystals are investigated. It is established that the plastic strain causes the relative concentrations of individual manganese emission centers to change together with conditions of excitation of the centers whose nearest environment has been rearranged upon plastic strain.  相似文献   
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