排序方式: 共有77条查询结果,搜索用时 15 毫秒
61.
62.
63.
表面增强拉曼散射(SERS)自1974年被Fleischmann等[1]发现以来,日益受到人们的重视.通过SERS谱图分析,可以获得物质结构及其与基体作用的信息.由于SERS可使拉曼信号增强105~106倍[2],并且在某些情况下银胶还能使表面吸附质的荧光猝灭[3,4], SERS常用来检测一些普通拉曼光谱难以检测的样品和考察界面络合物的形成. 相似文献
64.
65.
AWG中波导间耦合造成的相位畸变的分析 总被引:1,自引:1,他引:0
用(1,1)阶Pad啨近似的广角BPM计算了阵列波导光栅(AWG)中由于阵列波导间耦合造成的相位畸变以及由于相位畸变引起的相位误差分别考虑了光从中心/非中心输入波导入射两种情况结果表明,波导间的耦合会造成显著的相位畸变,但由此引起的相位误差却很小,光从中心输入波导入射时对应的相位误差10-3rad,从非中心输入波导入射时的相位误差约为10-2rad针对波导阵列边缘效应引起的相位畸变,设计AWG结构时,在阵列部分两侧增加了边缘辅助波导结构,从而消除了边缘效应,使得边缘阵列波导对应的相位误差从10-1rad量级减小为10-3(10-2)rad量级. 相似文献
66.
张玉虎 许甫荣 何建军 刘忠 周小红 甘再国 M. Oshima T. Hayakawa Y.Toh T.Shizuma J.Katakura Y. Hatsukawa M.Matsuda H.Kusakari M.Sugawara K.Furuno T.Komatsubara T.Une 温书贤 王治民 《中国科学G辑(英文版)》2003,46(4)
High-spin states in 182Au have been produced and studied via the 152Sm(35Cl,5nγ)182Au reaction. The level scheme consisting of the πh9/2(*)Vi13/2 and πi13/2(*)V i13/2 bands has been established for the first time. The low spin signature inversion in both bands has been found. The observed signature inversion phenomena can be interpreted qualitatively using the pairing and deformation self-consistent cranked Wood-Saxon calculations. 相似文献
67.
68.
69.
Nuclear reactions in stars occur between nuclei in the high-energy tail of the energy distribution and are sensitive to possible deviations from the standard equilibrium thermal-energy distribution, the well-known Maxwell-Boltzmann Distribution (MBD). Strong constraints on such deviations were made previously with the detailed helioseismic information of the solar structure. With a small deviation parameterized with a factor exp[-δ (E/kT)2], it was shown δ restricted between -0.005 and +0.002. These constraints have been carefully re-examined in the present work. We find that a normalization factor was missed in the previous modified MBD. In this work, the normalization factor c is calculated as a function of δ. It shows the factor c is almost unity within the range 0< δ ≤0.002, which supports the previous conclusion. However, it demonstrates that δ cannot take a negative value from the normalization point of view. As a result, a stronger constraint on δ is defined as 0≤ δ ≤0.002. The astrophysical implication on the solar neutrino fluxes is simply discussed based on a positive δ value of 0.003. The reduction of the 7Be and 8B neutrino fluxes expected from the modified MBD can possibly shed alternative light on the solar neutrino problem. In addition, the resonant reaction rates for the 14N(p, γ)15O reaction are calculated with a standard MBD and a modified MBD, respectively. It shows that the rates are quite sensitive even to a very small δ. This work demonstrates the importance and necessity of experimental verification or testing of the well-known MBD at high temperatures. 相似文献
70.