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排序方式: 共有605条查询结果,搜索用时 31 毫秒
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Zheng Baishu Zhou Fengxiang Liu Yi Wang Zhaoxu Liu Yuan Ding Xunlei 《Structural chemistry》2019,30(3):965-977
Structural Chemistry - A new type of halogen bond formed by supermetals or superalkalies with dihalogen molecules was analyzed by means of ab initio at the MP2/aug-cc-pVTZ level. The results reveal... 相似文献
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设计了具有高时间和空间分辨率EAST 快离子Dα 的光电检测系统,它由16 路光电倍增管(PMT)和电流放大器(采用蓝宝石材料代替传统印刷板电路)构成。为了使快离子Dα (FIDA)信号在中性束注入时能从其他光源的在同一光谱范围内的谱线中检测出来,系统参数设计为整体光子-电压增益5.0×109、电流放大器增益106V/A、-3dB 带宽500kHz。实验结果表明,该光电检测系统可以很好的检测到快离子Dα (FIDA)信号,并有助于从Dα 光的多普勒偏移光谱推断快离子特性。 相似文献
44.
Property of Image-Object Using TE/TM-polarized Wave in the Near-Field Optics with CCGM-FFT 下载免费PDF全文
Discretization of the Lippmann-Schwinger integral equation with complex conjugate gradient method and fast Fourier transform (CCGM-FFT) is solved, which can reduce the memory storage and the CPU time compared with the traditional method, MOM. Thus objects with large size and multiple scattering objects could be simulated with CCGM-FFT. The total intensity and the distribution of each field component of the dielectric and metallic objects under the excitation of the TE//TM-polarized wave are calculated with photon scanning tunnelling microscopy (PSTM) at the constant height. The simulating results are analysed and explained reasonably. The results show that the polarization plays an important role for imaging of PSTM. 相似文献
45.
Quasi-Random Resistor Network Model for Linear Magnetoresistance of Metal--Semiconductor Composite 下载免费PDF全文
XU Jie ZHANG Duan-Ming DENG Zong-Wei YANG Feng-Xia LI Zhi-Hua PAN Yuan 《中国物理快报》2008,25(11):4124-4127
A new model for the linear magentoresistance (MR) of the Ag2+δSe and Ag2+δ Te thin films is proposed. The thin film is considered as a metal--semiconductor composite and dispersed into an N×N quasi-random resistor network. The network is constructed from four-terminal resistors and the mobility of carries μ within the network has a quasi-random distribution, i.e. a Gaussian distribution with two constraint conditions. The model predicts that the MR increases with the increasing magnetic fields, and increases linearly at high field. Moreover, the MR decreases with the increasing temperatures. A good agreement between the theoretical MR and the available experimental data is found. 相似文献
46.
《Wave Motion》2018
The breather solutions of the Maxwell–Bloch equations in a two-level resonant system associated with the self-induced transparency phenomenon are constructed by the Darboux transformation. After constructing the formulas of the second-order breather solutions, the double degeneration and hybrid solutions are studied by the analytical form as well as figures. Our results might be helpful in such application or prevention of the rogue waves from breather solution interactions and degeneration in the nonlinear optical systems associated with the Maxwell–Bloch equations. 相似文献
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Zhe Wang Ting-Bi Yuan Zong-Yu Hou Wei-Dong Zhou Ji-Dong Lu Hong-Bin Ding Xiao-Yan Zeng 《Frontiers of Physics》2014,9(4):419-438
Laser-induced breakdown spectroscopy (LIBS) has been regarded as a future superstar for chemical analysis for years due to its unique features such as little or no sample preparation, remote sensing, and fast and multi-element analysis. Chinese LIBS comnmnity is one of the most dynamically developing communities in the World. The aim of the work is to inspect what have been done in China for LIBS development and, based on the understanding of the overall status, to identify the challenges and opportunities for the future development. In this paper, the scientific contributions from Chinese LIBS comlnunity are reviewed for the following four aspects: fimdamentals, instrumentation, data processing and modeling, and applications; and the driving force of LIBS development in China is analyzed, the critical issues for successful LIBS application are discussed, and in our opinion, the potential direction to improve the technology and to realize large scale commercialization in China is proposed. 相似文献
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Quantum Chemical Studies on Structure and Detonation Performance of Bis(2,2-dinitropropyl ethylene)formal 下载免费PDF全文
Based on the full optimized molecular geometric structures via B3LYP/6-311+G(2d,p) method, a new gem-dinitro energetic plasticizer, bis(2,2-dinitropropyl ethylene)formal was investigated in order to search for high-performance energetic material. IR spectrum, heat of formation, and detonation performances were predicted. The bond dissociation energies and bond orders for the weakest bonds were analyzed to investigate the thermal stability of the title compound. The results show that the four N-NO2 BDEs are nearly equal to the values of 164.38 kJ/mol, which shows that the title compound is a stable compound. The detonation velocity and pressure were evaluated by using Kamlet-Jacobs equations basedon the theoretical density and condensed HOF. The crystal structure obtained by molec-ular mechanics belongs to P21 space group, with lattice parameters Z=2, a=13.8017 ?, b=13.4072 ?, c=5.5635 ?. 相似文献