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981.
Sun Huibin Liu Yunzuo Zhou Jiewen Wu Yaodong 《Zeitschrift für Physik A Hadrons and Nuclei》1992,342(2):141-144
Theγ-rays emitted in theβ-decay of182Ta have been reinvestigated with improved statistics in attempting to clarify the reported new levels at 1460.41, 1592.98, 1620.36, 1712.29 and 1762.91 keV in182W observed in theβ-decay of182Ta. The present study demonstrated that the fifteen newγ-rays, which were used to support the existence of the five new levels, are not relevant to theγ-decay of182Ta. Therefore the five new levels are not populated in this decay. Additionally, theγ-ray with an energy of 1035.6 keV (0 2 + →2 1 + ) deexciting theβ-band head in182W is observed for the first time in the present decay study and the previous tentative placement of the 351.0 keVγ-ray in the level scheme is confirmed by the present coincidence measurements. 相似文献
982.
Shao-Chen Yang Qihuang Gong Zongju Xia Y. H. Zou Y. Q. Wu D. Qiang Y. L. Sun Z. N. Gu 《Applied physics. B, Lasers and optics》1992,55(1):51-53
The nonlinear third-order optical susceptibility of C70 in a toluene solution is measured for the first time by the method of degenerate four-wave mixing using 10 ns laser pulses at 1.06 m. The third-order susceptibility X
in
(3)
is 5.6×10–12 esu for a C70 toluene solution at a concentration of 0.476 g/l. The correspondent magnitude of the hyperpolarizability 1111 of the C70 molecule is 1.2×10–30 esu which is in a good agreement with the prediction given by the model of a free electron in a spherical box. 相似文献
983.
984.
985.
986.
A new quantum group is derived from a nonstandard braid group representation by employing the Faddeev-Reshetikhin-Takhtajan constructive method. The classical limit is not a Lie superalgebra, despite relations like x
2–y
2=0. We classify all finite-dimensional irreducible representations of the new Hopf algebra and find only one- and two-dimensional ones. 相似文献
987.
The electronic conductivity of a particular metallic particles/semiconductor system, i.e. Ag particles in cesium-oxide thin film, has been studied. The experimental results show a transition from a polycrystalline semiconductor to metallic behavior as characterized by the conductivity-temperature curve (log bs 1/T), and a five order of magnitude increase in the room temperature value of the conductivity with surface Ag content increasing from an equivalent thickness of 2Å to 20Å. It was observed by TEM that the deposited Ag was mainly in the form of dispersed particles with the particle size varying from 20 to 200Å and their separations varying from hundreds to tens of angstroms over the Ag content range. These results can hardly be explained with the model of direct electron tunneling through the Schottky barrier at the Ag-particle/cesium-oxide interface. A microstructure model with two conduction layers is presented, and an analogy to the hopping conduction mechanism is proposed to explain the electronic conduction behavior. This model predicts that the attenuation length for electronic wavefunctions localized at Ag particles falls in the range 20–50Å. 相似文献
988.
989.
990.
We add to the known examples of complete Kähler manifolds with negative sectional curvature by showing that the following three classes of domains in euclidean spaces also belong: perturbations of ellipsoidal domains in ?n, intersections of complex-ellipsoidal domains in ?2, and intersections of fractional linear transforms of the unit ball in ?2. In the process, we prove the following theorem in differential geometry: in the intersection of two complex-ellipsoidal domains in ?2, the sum of the Bergman metrics is a Kähler metric with negative curvature operator. 相似文献