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921.
922.
T.R. Saitoh N. Hashimoto G. Sletten R.A. Bark S. Törmänen M. Bergström K. Furuno K. Furutaka G.B. Hagemann T. Hayakawa T. Komatsubara A. Maj S. Mitarai M. Oshima J. Sampson T. Shizuma P.G. Varmette 《The European Physical Journal A - Hadrons and Nuclei》1998,3(3):197-199
High-spin states in 181Ta have been studied via the 176Yb(11B,α2n) reaction at 52 MeV using the PEX array and at 57 MeV using the NORDBALL array, with α-particle detection. The previously
known, Kπ=(7/2)+ ground state band and Kπ=(9/2)− band have been extended to spins (29/2)+ and (31/2)−, respectively. Two new one-quasiparticle bands, the Kπ=(5/2)+ band built on the known (5/2)+ isomer and a Kπ=((1/2)−) band have been observed. Two other rotational bands with three-quasiparticle structure, Kπ=(15/2)− and ((19/2)+ with π(7/2)[404]ν2(1/2)[510](9/2)[624] and π(9/2)[514]ν2(1/2)[510](9/2)[624] configurations, respectively, have been newly observed. The half-life of the Kπ=((19/2)+) bandhead which decays to the head of the (15/2)− band has been measured to be 140(36) ns. However, transitions from the ((19/2)+) state to the (15/2)− band have not been observed.
Received: 26 August 1998 相似文献
923.
We analyze the possibility of resonant optical radiation inducing evaporation and condensation growth of aerosol particles
suspended in a vapor-gas mixture. The molecules of the vapor absorb radiation selectively as to velocity. We examine the Knudsen
regime, in which the particle radius is much smaller than the mean free path of the molecules.
Zh. éksp. Teor. Fiz. 113, 1036–1047 (March 1998) 相似文献
924.
The optical absorption of GaAs crystals with thicknesses d=0.4−4.4 μm is measured in the exciton-polariton resonance region at a temperature of 1.7 K. As the thickness is reduced,
both a broadening of the exciton line and increased absorption with a negligible Stark shift are observed. The way the absorption
spectra vary with crystal thickness is examined in terms of a competition between two regions for light-exciton interactions
in the crystal: in the field of surface charges and electric-field free.
Fiz. Tverd. Tela (St. Petersburg) 40, 869–871 (May 1998) 相似文献
925.
926.
G. A. Malygin 《Physics of the Solid State》1998,40(4):629-633
This paper discusses theoretically the mechanism that causes the temperature dependences of the yield point and yield stress,
along with their rate coefficients, to deviate from behavior characteristic of thermally activated plastic strain at low temperatures
(<30 K). At this time the existence of such deviations, e.g., anomalous decreases in the values of these characteristics in
this temperature range, is explained by arguing that the process whereby dislocations overcome local barriers has inertia.
It is shown that the observed anomalies can be caused by the development of thermal instability in the plastic strain at low
temperatures. In contrast to inertia-related effects, thermal effects allow us to explain the plasticity of crystals at low
temperatures without contradiction and within the framework of a single mechanism, including the unstable, discontinuous character
of plastic strain that is characteristic of these temperatures.
Fiz. Tverd. Tela (St. Petersburg) 40, 684–689 (April 1998) 相似文献
927.
S. O. Romanovskii A. V. Sel’kin I. G. Stamov N. A. Feoktistov 《Physics of the Solid State》1998,40(5):814-815
A study is made of the effect of electric fields on the exciton states of β-ZnP2 crystals (T=77 K) in structures with Schottky barriers formed by depositing semitransparent electrically-conducting InSnO2 films on the crystal surface. The observed changes in the exciton optical reflection spectra when an electrical potential
is applied to a barrier are explained by the shift and broadening of the exciton level caused by the Stark effect. The experimental
data are compared with calculations based on a theory of exciton optical reflection from planar spatially nonuniform structures.
Fiz. Tverd. Tela (St. Petersburg) 40, 884–886 (May 1998) 相似文献
928.
G. V. Loseva S. G. Ovchinnikov É. K. Yakubailik N. I. Kiselev T. A. Gaidalova 《Physics of the Solid State》1998,40(10):1715-1717
A study has been made of the FexV1−x
S solid solutions with 0<x<0.5. For the compounds with x>0.1, x-ray diffraction analysis discloses a V5S8 superstructure. Samples with x>0.1 are magnetically ordered at room temperature. The concentration dependences of resistivity and magnetization exhibit
sharp peaks for x=0.1 and x=0.2, respectively. The main features of the structure and electronic properties have been qualitatively explained in terms
of the three-band exciton-insulator model, and the maxima in resistivity and magnetization are assigned to the formation of
localized magnetic moments with S=1, which become delocalized with increasing x.
Fiz. Tverd. Tela (St. Petersburg) 40, 1890–1893 (October 1998) 相似文献
929.
930.
The twisting power of chiral probes in nematics is interpreted in terms of a shape model, in which the surface elements of the solute molecules tend to align with the local director. The theoretical treatment is based on a previous approach, suitable for relating order parameters in nematics to molecular shape, and leads to the definition of a molecular pseudo-tensor whose orientational average determines the pitch and handedness of the helical macrostructures. Results of numerical calculations performed for distorted biphenyl and binaphthyl molecules are in agreement with the experimental results. 相似文献