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31.
The partial cross section for radiative neutron capture by 48Ti nuclei was measured as a function of neutron energy. The method of neutron spectrometry used is based on the shift in the energy of the primary γ transition in response to a change in the energy of the captured neutron. The reaction 7Li(p, n)7Be was used as a neutron source. Protons were accelerated by a Van de Graaff electrostatic generator up to energies of 60 keV above the reaction threshold, which provided neutron energies in the range from 10 to 120 keV. The partial widths of some resonances were determined. The radiative strength functions of E1 and M1 transitions to the first excited state were calculated. __________ Translated from Yadernaya Fizika, Vol. 66, No. 1, 2003, pp. 47–50. Original Russian Text Copyright ? 2003 by Voinov, Serov, Popov, Gundorin, Kobzev, Parzhitski.  相似文献   
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This paper presents results of the experiments aimed at producing long-lived superheavy elements located near the spherical-shell closures with Z ⩾ 114 and N ⩾ 172 in the 244Pu + 48Ca and 248Cm + 48Ca reactions. The large measured α-particle energies of the newly observed nuclei, together with the long decay times and spontaneous fission terminating the chains, offer evidence of the decay of nuclei with high atomic numbers. The decay properties of the synthesized nuclei are consistent with the consecutive α-decays originating from the parent nuclides 288, 289114 and 292116, produced in the 3n and 4n evaporation channels with cross-sections of about a picobarn. The present observations can be considered as experimental evidence of the existence of the “island of stability” of superheavy elements. Received: 21 March 2002 / Accepted: 16 May 2002 / Published online: 31 October 2002 RID="a" ID="a"e-mail: utyonkov@sungns.jinr.ru  相似文献   
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The motion of a body in an ideal incompressible fluid flow without vortices in the absence of external forces is considered. It is demonstrated that the body can move inertially from the state at rest if its shape satisfies certain conditions. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 4, pp. 214–219, July–August, 2008.  相似文献   
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We present the results of experiments on the implantation of KTP (KTiPO4) ferroelectric nanoparticles into pores of synthetic opal along with the data on spectral analysis of the reflection coefficients of specimens obtained. KTP powder was irradiated by an ultraviolet KrF laser in water, which increased the pore filling efficiency.  相似文献   
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The possibilities of the extraction and collimation of a circulating beam by a new method due to the reflection of particles in crystals with axial orientation were experimentally investigated in the Fall 2010 run at the U-70 synchrotron. Such crystals have positive features, because the axial potential is five times larger than the planar potential. It has been shown that the collimation efficiency can reach 90% due to axial effects in the crystal. Losses of the circulating beam on a collimator have been reduced by several times; this makes it possible to suppress the muon jet near the steel collimator of the circulating beam.  相似文献   
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The problem of the construction of chi-square type tests for discrete (one- and multidimensional) distributions of exponential type is considered in detail. In particular, as an example, the Stirling distribution of the second kind is investigated a table of the best unbiased estimators of certain functions of the distribution parameters is given.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova Akademii Nauk SSSR, Vol. 184, pp. 62–79, 1990.  相似文献   
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