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991.
The absolute values of the cross sections for the production of target fragments in the interaction of copper with 7Li ions at an energy of 35 MeV per nucleon were measured. The measurements were performed by recording the yields of radioactive nuclear residues with the aid of a semiconductor detector from ultrapure germanium. The charge and isobaric distributions in the mass-number range 22–69 amu were used to deduce the mass yield of reaction products and to calculate the total interaction cross section. The results are presented that were derived from a comparison with data obtained for 12C + Cu reactions and with estimates based on theoretical models.  相似文献   
992.
Results are presented that were obtained by measuring single-spin asymmetry in the inclusive production of neutral pions in the reaction p+p ↑→ π 0+X at x F≈0. A beam of 70-GeV protons was extracted directly from the vacuum chamber of the accelerator by means of a bent single crystal. For transverse momenta in the range 1.0<p T<3.0 GeV/c, the single-spin asymmetry independently measured by two detectors is zero within the errors. This result is in agreement with Fermilab data obtained at 200 GeV, but it is at odds with CERN data measured at 24 GeV.  相似文献   
993.
994.
The effective dielectric, piezoelectric, and elastic constants of two-phase macroscopically piezoactive 3-0 and 3-3 composites are calculated. It is assumed that one of the components is a polarized ferroelectric ceramic material and the other is an inactive material with variable elastic properties. The limiting case when the elastic compliances of the inactive material tend to infinity (porous ferroelectric ceramics) is considered. The adequacy of this model to production technologies of piezoelectric composites is discussed. Computational results are compared with experimental data.  相似文献   
995.
A new formula that relates the acoustic Grüneisen parameter to the Poisson ratio is suggested on the basis of the previously derived expression for this parameter.  相似文献   
996.
Intensities of principal diffraction maxima for a phase reflection diffraction grating with a rectangular groove profile were calculated by the Fresnel method, using a special algorithm. The procedure under consideration enables us to perform high-efficiency calculations of diffracted-beam characteristics and can be used extensively to optimize diffraction-grating parameters.__________This revised version was published online in May 2005 with a correction on affiliation.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 38–41, November 2004.  相似文献   
997.
Two nonstationary cosmological models with rotation are constructed for the Bianchi II metric within the Einstein gravitation theory. The first model is filled with a co-moving perfect liquid and radiation field and is characterized by nonzero expansion, rotation, and acceleration. A perfect liquid which is not co-moving with a reference system is a source of gravitation for the second model. The second model corresponds to nonzero rotations and accelerations.  相似文献   
998.
In the present paper, the main probabilistic characteristics (the mathematical expectation, variance, and correlation function) of the amount of harmful substances in anthropogenic formations are calculated under the stationary conditions when the stream of these substances is a recurrent stream of events.  相似文献   
999.
1000.
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