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991.
992.
CHEN Minghua YAO Minyu ZHENG Haocheng ZHANG Jianfeng XU Lei XIE Shizhong GAO Yizhi 《中国光学快报(英文版)》2000,9(1)
Properties of four-wave mixing (FWM) in the semiconductor laser amplifier are studied experimentally in this paper. The optical phase conjugation of the mixing wave is applied to compensate the chromatic dispersion of transmission fiber. It is presented experimental results of the transmission of short optical pulses with 12-ps width over 204 km standard single mode fiber. The results confirm that mid-span spectral inversion (MSSI) employing FWM in a semiconductor laser amplifier is one of potential dispersion compensation techniques for optical transmission over standard single mode fiber with bit rate beyond 40Gb/s. 相似文献
993.
Ke-Sheng Song Lei Liu Xiao-Song Li Qing-Xiang Guo 《Research on Chemical Intermediates》2000,26(4):319-325
PM3 calculations were performed on the inclusion complexation of α-cyclodextrin (α-CD) with the ground and excited quinones
from a complete and unrestricted geometry optimization and conformational analysis. It was found that the complexation of
α-CD with the triplet quinone was significantly more favourable than that with the singlet one. Hence, caution should be given
when extrapolating excited state behaviour to the supramolecular systems in their ground state. 相似文献
994.
Jiaye Li Jinping Wu Chenggang Zhou Bo Han Xinjian Lei Roy Gordon Hansong Cheng 《International journal of quantum chemistry》2009,109(4):756-763
We present a first‐principles study on the relative stability of cobalt‐ and nickel‐based amidinate complexes against β‐migration using density functional theory. Factors that influence the reactivity of these compounds were carefully addressed and the calculated molecular structures are in excellent agreement with the available crystal structural data. Reaction energies as well as activation barriers of β‐migration were evaluated. The predicted relative stability of the selected compounds is consistent with experimental observations. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 相似文献
995.
The principle of step-scan Fourier transform infrared (FTIR) spectroscopy is introduced. Double modulation step-scan FTIR technique is used to obtain the quantum cascade laser's stacked emission spectra in the time domain. Optical property and thermal accumulation of devices due to large drive current are analyzed. 相似文献
996.
本文提出了软X射线条纹相机与吸收膜相耦合测量等离子体温度的实验原理与方法,编制了数值计算程序SCC,给出了平面金靶在1.06μm激光(LF—II~=激光装置)作用下,靶面功率密度约10~(14)W/cm~2的辐射温度。并对温度处理中存在的误差,以及把此方法推广到能谱的时间分辨和温度的空间分辨测量中的可能性进行了讨论。 相似文献
997.
998.
Let G =(V,E) be a graph without isolated vertices.A set S V is a domination set of G if every vertex in V -S is adjacent to a vertex in S,that is N[S] = V .The domination number of G,denoted by γ(G),is the minimum cardinality of a domination set of G.A set S V is a paired-domination set of G if S is a domination set of G and the induced subgraph G[S]has a perfect matching.The paired-domination number,denoted by γpr(G),is defined to be the minimum cardinality of a paired-domination set S in G.A subset S V is a power domination set of G if all vertices of V can be observed recursively by the following rules:(i) all vertices in N[S] are observed initially,and(ii) if an observed vertex u has all neighbors observed except one neighbor v,then v is observed(by u).The power domination number,denoted by γp(G),is the minimum cardinality of a power domination set of G.In this paper,the constructive characterizations for trees with γp = γ and γpr = γp are provided respectively. 相似文献
999.
Jerby E. Kesar A. Korol M. Lei L. Dikhtyar V. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1999,27(2):445-455
The cyclotron-resonance-maser (CRM) array is a radiation source which consists of CRM elements coupled together under a common magnetic field. Each CRM-element employs a low-energy electron-beam which performs a cyclotron interaction with the local electromagnetic wave. These waves can be coupled together among the CRM elements, hence the interaction is coherently synchronized in the entire array. The implementation of the CRM-array approach may alleviate several technological difficulties which impede the development of single-beam gyro-devices. Furthermore, it proposes new features, such as the phased-array antenna incorporated in the CRM-array itself. The CRM-array studies may lead to the development of compact, high-power radiation sources operating at low voltages. This paper introduces new conceptual schemes of CRM-arrays, and presents the progress in related theoretical and experimental studies in our laboratory. These include a multimode analysis of a CRM-array, and a first operation of this device with five carbon-fiber cathodes 相似文献
1000.
ZHENG Jianguo LIU Fang WANG Lei JIAO Licheng 《Chinese Journal of Lasers》2001,10(6):427-431
1 Introduction Knowledgediscoveryindatabases (KDD)isconcernedwithextractingusefulinformationfromdatabases.Thetermdatamininghashistoricallybeenusedinthedatabasecommunityandinstatistics (ofteninthelatterwithnegativeconnotationstoindicateimproperdataanaly… 相似文献