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971.
Electron spin resonance (ESR), electrical and optical measurements have been made for Ge1?xSex (0?x?0.35) films in order to elucidate relations between tetrahedrally bonded amorphous semiconductors and chalcogenide amorphous semiconductors. The ESR signal due to dangling bonds in amorphous Ge decreases by increasing Se content. For more than about 20 at. % Se, the electrical conductivity is the activation type and the optical gap increases with the increase of Se content. The model of charged dangling bonds by Street and Mott seems to explain the experimental results. 相似文献
972.
973.
N. Matsuoka K. Hatanaka T. Saito T. Itahashi K. Hosono A. Shimizu M. Kondo F. Ohtani O. Cynshi 《Nuclear Physics A》1982,391(2):357-376
Proton-neutron angular correlations in the 12C, 51V and 118Sn(d, pn) reactions have been measured at 56 MeV to investigate the deuteron breakup process. The elastic breakup which leaves the target nucleus in its ground state dominates the coincident spectra. The elastic breakup cross sections are estimated to be 36–48% of the inclusive breakup yields at 15° or 17.5°. In the angular correlations the protons are emitted predominantly on the side of the beam opposite to the neutrons. The experimental data have been analyzed using the prior-form DWBA. For both nuclear and Coulomb breakup, sufficient convergence of the calculations is obtained by including the pn angular momenta up to l = 2. For the nuclear breakup calculations, the l = 0 and 2 contributions dominate the cross sections. For the Coulomb breakup the l = 1 contribution is predominant. In the calculations the effect of the Coulomb breakup is seen at forward angles of the angular correlation. The DWBA calculations reproduce fairly well the coincident energy spectra and the angular correlations in the angular region where the protons are emitted on the side of the beam opposite to the neutrons. On the other hand the calculations overestimate the break-up cross sections by a factor of 2 to 10 in the angular region where the protons are emitted on the same side of the beam as the neutrons. The distributions of deuteron c.m. angular momenta that contribute to the breakup amplitude are examined to obtain information on the region of space in which the breakup reactions takes place. 相似文献
974.
A new ten-membered lactone, pyrenolide A, was identified as a new fungal morphogenic substance and its structure including absolute stereochemistry was elucidated. 相似文献
975.
T. Shimizu 《Physics letters. A》1981,84(3):85-88
A new model is proposed which has a strange attractor as a stationary state for small parameter values. The asymptotic form of the strange attractor is discussed by using the method of nonlinear scales. 相似文献
976.
K. Shimizu 《Journal of magnetism and magnetic materials》1987,70(1-3):178-180
Spin-echo NMR measurements on 155Gd, 159Tb and 175Lu have been done for the cubic Laves phase compounds Gd1−xLuxFe2 and Tb1−xLuxFex. The observed hyperfine fields of Gd and Lu in those compounds increase with increasing Lu concentration. The concentration dependence of the Lu hyperfine field is qualitatively discussed. 相似文献
977.
978.
979.
A. Schenzle R. G. Devoe R. G. Brewer F. Shimizu K. Umezu H. Takuma S. K. Saha R. W. Hellwarth G. C. Bjorklund W. Zapka M. D. Levenson A. C. Tam W. Lenth F. M. Schellenberg T. F. Gallagher R. Kachru F. Gounand W. H. Weber R. W. Terhune A. le Floch J. M. Lenormand R. le Naour J. E. M. Goldsmith 《Applied physics. B, Lasers and optics》1982,28(2-3):297-305
980.