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81.
利用普通幂级数发生函数方法,通过对发生函数进行xD算子,得到和式∑k=0^nμ^kf(k)的计算公式,并计算该类和式+ 相似文献
82.
A. Shaporenko A. Terfort M. Grunze M. Zharnikov 《Journal of Electron Spectroscopy and Related Phenomena》2006
Analysis of photoemission spectra of complex thioaromatic self-assembled monolayers (SAMs) requires the knowledge and understanding of such spectra for the basic systems. Keeping this goal in mind, synchrotron-based high-resolution X-ray photoelectron spectroscopy was used to characterize SAMs formed from the simplest thioaromatic compounds, namely thiophenol, 1,1′-biphenyl-4-thiol and 1,1′;4′,1″-terphenyl-4-thiol on evaporated Au(1 1 1) and Ag(1 1 1) substrates. The acquired S 2p and C 1s spectra were analyzed in terms of fine structure and initial and final state effects in the photoemission process. The assignment of the individual spectral features was considered in detail. Conclusions on quality and chemical and structural homogeneity of the investigated SAMs were derived. 相似文献
83.
从D触发器激励表入手,分别给出了采用单边沿D触发器和双边沿D触发器的2^n进制异步加法计数器、减法计数器的设计方法.在此基础上,采用逻辑函数修改技术,通过实例讨论了基于单边沿D触发器和双边沿D触发器的异步任意进制计数器的设计.该设计方法方便,快速,具有一定的实用意义. 相似文献
84.
Hongrui Zhang Mingju Chao Mingyi Gao Liwen Zhang Jianquan Yao 《Optics & Laser Technology》2003,35(6):573-449
A fiber-coupled diode-single-end-pumped Nd:YVO4 laser with an Nd:YVO4 crystal of 0.3 at% doping concentration and 3×3×10 mm3 dimensions was reported. 14.850 W of continuous-wave output power in an M2 factor of 1.12 was obtained under pump power of 27.365 W, with an optical conversion efficiency of 60.49%, and a slope efficiency of 64.5%. 相似文献
85.
构造了第孙中禹种强度不等的非对称三态叠加多模叠加态光场|ψ1(ABC)〉q.利用多模压缩态理论研究了态|ψ1(ABC)〉q第一正交分量高次和压缩.结果发现:①当构成态|ψ1(ABC)〉q的三个多模相干态光场的强度不相等时,在一定条件下,态|ψ1(ABC)〉q的第一正交分量可出现任意幂次的高次和压缩.②当上述的三个多模相干态光场强度相等时,态|ψ1(ABC)〉q的第一正交分量的高次和压缩现象消失.在这种情况下,态|ψ1(ABC)〉q的第一正交分量恒处于NH最小测不准态. 相似文献
86.
KANG Zihua WANG Mingwei QIAN Jiamei RAO Jun LI Xiujuan ZHENG Tieliu WANG Xuehua 《核工业西南物理研究院年报(英文版)》2004,(1):73-76
Lower hybrid wave (LHW), electro cyclotron (EC) and neutral beam injection (NBI) etc. are the important methods of auxiliary heating. They would be devoted to the HL-2A tokamak step by step. In order to satisfy the debug of each system and the need of the experiment, the system should be equipped with high voltage pulse power (HVPP) according to the requirement. 相似文献
87.
In this paper, an interior point cutting plane method (IPCPM)is applied to solve optimal power flow (OPF) problems. Comparedwith the simplex cutting plane method (SCPM), the IPCPM is simpler,and efficient because of its polynomial-time characteristic.Issues in implementing IPCPM for OPF problems are addressed,including (1) how to generate cutting planes without using thesimplex tableau, (2) how to identify the basis variables inIPCPM, and (3) how to generate mixed integer cutting planes.The calculation speed of the proposed algorithm is further enhancedby utilizing the sparsity features of the OPF formulation. Numericalsimulations on IEEE 14-300-bus test systems have shown thatthe proposed method is effective. 相似文献
88.
89.
Margherita De RosaMaria Rosaria Acocella Rosaria VillanoAnnunziata Soriente Arrigo Scettri 《Tetrahedron letters》2003,44(32):6087-6090
Initial concentration of enantioenriched or enantiopure catalysts proved to be an important factor for the achievement of a more pronounced amplification of ee's in the Ti(IV)/BINOL-catalyzed aldol reaction of an O-silyldienolate. 相似文献
90.
N. S. Kazak E. G. Katranji I. A. Utkin A. A. Ryzhevich A. N. Khilo 《Journal of Applied Spectroscopy》2004,71(5):697-701
The phenomenon of self-diffraction of Bessel light beams (BLB) in a nonlinear liquid medium has been studied experimentally and theoretically for the first time. Diffraction maxima which do not correspond to integer orders for an induced periodic structure have been registered. It has been shown that the appearance of these maxima is due to the initial BLB modulation, which can be caused by the departure of the axicon refracting surface from the ideal conical surface, as well as by the imperfection of the form of the Gaussian beam incident on the axicon. 相似文献