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排序方式: 共有9891条查询结果,搜索用时 15 毫秒
891.
892.
A. Ferrer D. Treille P. Rivet A. Volte P. Benkheiri G. De Rosny A. Rougé B. Bouquet B. DAlmagne H. Nguyen P. Petroff F. Richard P. Roudeau J. Six H. Yoshida 《Nuclear Physics B》1981,178(3):373-391
We have analysed about 85 000 fast Λ0 events, obtained in a fast proton triggered experiment performed at the CERN-Ω spectrometer at 9 and 12 GeV/c incident π? beam. Nearly 2500 Λ0K+π? events have been isolated. We find strong production of quasi-two-body processes and consistent with u-channel hyperon exchange. Results on Λ0 polarization, K10 decay parameters and differential cross sections are given for and final states. A comparison is made with the associated backward production seen in the four-prong reaction π?p→pK?K+π? obtained in the same experiment. 相似文献
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895.
We report results obtained from thermally stimulated current and capacitance measurements of metal-SiO-metal structures having different metals for the electrodes. Dependence of relaxed charge on the polarized electrode suggests the existence of space charge near the metal-insulator interface. The measurements of capacitance under superimposed DC voltages support this interpretation and show that space charge is not negligible at high fields. The density of lacalised states evaluated from the data is of the order of 1017 cm?3 相似文献
896.
The successive stages of the oxidation of Ni(100) have been investigated by angle-resolved uv photoemission. The adsorption spectra are very similar to that measured previously for the same surface saturated with sulphur. Results are interpreted using recent theoretical calculations. It is found that this interpretation can be extended to the other chalcogens adsorbed on Ni(100). When increasing oxygen exposures, photoemission spectra have shown a continuity of the electronic character in the oxidation process. 相似文献
897.
Nguyen Van Giai 《Physics letters. [Part B]》1981,105(1):11-13
The multiple strength associated with the operator rLYL for L? 6 is distributed at much lower energies when calculated for nucleons moving in a finite potential well than when a harmonic oscillator well is used. The residual interactions would push these isoscalar resonances further down. 相似文献
898.
The design and performance of millimeter-wave microstrip/suspended-stripline end-coupled bandpass filters are presented. Filters in Ka-band (26.5 to 40 GHz) and W-band (75 to 110 GHz) using suspended-stripline and microstrip have been designed. Good agreement between the experimental results and those predicted theoretically was observed. Measured passband insertion losses of less than 1 and 0.5 dB have been achieved in W- and Ka-band, respectively. An extremely wideband waveguide-to-microstrip transition with an insertion loss of 0.25 dB over the full W-band is also presented. 相似文献
899.
This work is concerned with rigid-plastic limit analysis of shells of revolution subject to rotationally symmetric loadings. These shells, of arbitrary shape, are discretized into a series of finite elements, each being a conical shell. The von Mises condition, valid for sandwich shells, is used to compare the results obtained with existing values. After assembling the finite elements, the limit analysis program is reduced to a simple application of the non-linear programming technique where both the sequential unconstrained minimization technique (SUMT) and feasible conjugate direction (FCD) are utilized respectively for statically admissible and kinematically admissible approaches. Therefore, upper bounds and lower bounds of the collapse loads are found for some sample problems : conical, spherical, ellipsoidal, torispherical shells etc. These numerical results are illustrated and compared with existing ones described in the literature. 相似文献
900.