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排序方式: 共有1831条查询结果,搜索用时 15 毫秒
931.
High-spin states of the 115Te were studied by in-beam spectroscopy with the 89Y (29Si, p2n) fusion-evaporation reaction at a beam energy of 108 MeV. γ?γ coincidence and γ?γ angular correlation analyses were employed for determining the level scheme of 115Te. We have identified two vibrational-like bands built on the νh11/2 and νg7/2 quasiparticle states and the noncollective oblate states from the full alignment of quasiparticle configurations. In addition, a regular ΔI = 2 sequence with positive-parity was found for the first time in odd-A Te nuclei. This sequence is interpreted as a deformed structure resulting from three-quasiparticle alignment having the [π(g7/2, h 11/2) ? ν(h 11/2)] configuration. Calculations of total Routhian surfaces and cranked shell model were performed and were used for assigning quasiparticle configurations to the states in 115Te.  相似文献   
932.
An exact energy expression for a physical black hole is derived by considering the escape of a photon from the black hole. The mass of the black hole within its horizon is found to be twice its mass as observed at infinity. This result is important in understanding gravitational waves in black hole collisions.  相似文献   
933.
In traffic modeling, the computation of workload distributions plays a prominent role, since they influence the quality of service parameters. This paper deals with different ways to determine the workload distributions of a GI/GI/1 service system accurately. We discuss two different techniques, the polynomial factorization approach and the Wiener–Hopf factorization. These methods factorize the server system's characteristic polynomial to compute the workload. Starting with classical algorithms to obtain initial approximations, we enhance them using verification techniques to guarantee the correctness of the results.  相似文献   
934.
在强激光放大系统中,使用C_3H_6O作为非线性介质,获得了高效的SBS效应,Stokes波一次反射率~60%,末级激光放大器对Stokes波的能量放大率达到3,Stokes波脉宽压缩率为4,功率放大系数达到12,经SBS后,激光近场强度分布得到明显改善,在强泵浦下,Stokes波了现高频调制。对实验结果及其应用前景进行了讨论。  相似文献   
935.
Temperature-dependent evolution of surface corrugation and the interface dislocation in In0.15Ga0.85As epilayer on GaAs(100) substrate grown by chemical beam epitaxy using unprecracked monoethylarsine have been investigated by atomic force microscope (AFM) and transmission electron microscopy (TEM). AFM images showed that the line direction of surface ridge changes from [011] to [0 1] with increasing temperature. However, TEM micrographs showed that dislocation networks are formed along both [011] and [0 1] directions at the interface. These results indicate that growth kinetics on the terrace and at surface steps generated by the dislocations play an important role in determining the direction of surface corrugation. We suggest that the temperature-dependent change of surface corrugation is caused by an anisotropic surface diffusion on the terrace and different sticking probability of adsorbates on the surface steps which were produced by interface misfit dislocation along the two orthogonal surface directions.  相似文献   
936.
The electron temperature and plasma density at the lateral distance of 125 /spl mu/m from the center of sustaining electrode gap have been investigated by a Langmuir probe along with the high-speed discharge image in coplanar alternating current plasma display panels. The plasma density at the lateral distance of 125 /spl mu/m from the center of sustaining electrode gap is shown to be maximum value of 3.7/spl times/10/sup 11/ cm/sup -3/, whereas the electron temperature is measured to be decreased from 1.8 to 0.8 eV as the gas pressure increases from 150 to 400 torr in this experiment. It is noted that the electron temperatures measured by the Langmuir probe and high-speed image camera are in good agreement with each other within 5% error limit.  相似文献   
937.
The temperature dependence of the tunneling magnetoresistance (TMR) for magnetic tunneling junctions is investigated experimentally before and after the sample is annealed. As grown, the TMR is observed to increase with temperature from 80 to 160 K. A modified Julliere model in conjunction with a spin-dependent two-step tunneling is suggested to describe this temperature dependence.  相似文献   
938.
We investigate the structure and the formation energy of the pentagon–heptagon pairs (5775) defects of BN nanotubes using a molecular-mechanics method. For (n, 0) BN nanotubes, the homoelemental bonds of the 5775 defect may be located nearly either parallel or perpendicularly in the direction of tube axis. The former is energetically favored and strongly affects the reduction of the strain with decreasing radius. The formation energy of the 5775 defect, which increases with increasing radius, is lower than that of the tetragon–octagon pairs (4884). The 5775 defect of BN nanotubes is structurally and energetically stable, as compared to the 4884 defect.  相似文献   
939.
液相色谱水-异丙醇体系测定脂溶性维生素A,D,E   总被引:4,自引:0,他引:4  
利用反相高效液相色谱研究了混合药片中的脂溶性维生素A,D,E的同时测定。有不同比例的水:异丙醇体系分析这三种维生素,确定25:75(ф)的水:异丙醇体系为最佳流动相。测定了不同萃取条件下的脂溶性维生素的回收率,回收率均94%以上。使用9维他片作为样品。本方法简单,可靠,结果令人满意。  相似文献   
940.
The aim of this study was to evaluate whether the Th17 and Treg cell infiltration into allograft tissue is associated with the severity of allograft dysfunction and tissue injury in acute T cell-mediated rejection (ATCMR). Seventy-one allograft tissues with biopsy-proven ATCMR were included. The biopsy specimens were immunostained for FOXP3 and IL-17. The allograft function was assessed at biopsy by measuring serum creatinine (Scr) concentration, and by applying the modified diet in renal disease (MDRD) formula, which provides the estimated glomerular filtration rate (eGFR). The severity of allograft tissue injury was assessed by calculating tissue injury scores using the Banff classification. The average numbers of infiltrating Treg and Th17 cells were 11.6 ± 12.2 cells/mm2 and 5.6 ± 8.0 cells/mm2, respectively. The average Treg/Th17 ratio was 5.6 ± 8.2. The Treg/Th17 ratio was significantly associated with allograft function (Scr and MDRD eGFR) and with the severity of interstitial injury and tubular injury (P < 0.05, all parameters). In separate analyses of the number of infiltrating Treg and Th17 cells, Th17 cell infiltration was significantly associated with allograft function and the severity of tissue injury. By contrast, Treg cell infiltration was not significantly associated with allograft dysfunction or the severity of tissue injury. The results of this study show that higher infiltration of Th17 cell compared with Treg cell is significantly associated with the severity of allograft dysfunction and tissue injury.  相似文献   
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