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61.
Microstructured (atomized) and nanostructured (milled) Fe60Al40 powders together with their corresponding coatings synthesized by High Velocity Oxy-fuel (HVOF) or Atmospheric Plasma Spray (APS) thermal spraying techniques have been characterized by Mössbauer Spectroscopy (MS) and X-ray Diffraction (XRD). The evolution of the microstructure and the atomic ordering degree in the powders and coatings are discussed at the light of the various processing conditions. The operational correlation between the parameters of the duplex morphology of coatings and the processing parameters is discussed.  相似文献   
62.
李志荣 《大学数学》2006,22(2):100-104
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   
63.
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   
64.
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   
65.
Landfill gas, cryotrapped on a loop fashioned from a length of a capillary gas chromatography (GC) column, was examined for volatile organometallic compounds (VOMCs) and for volatile organic compounds (VOCs) by using GC–mass spectrometry (MS). A large number of organic components were present and many were identified, but the only VOMCs present in high enough concentrations to be detected were trimethylstibine and tetramethyltin. The use of inductively coupled plasma (ICP)‐MS as an element‐specific detector allowed the identification of a number of other organometallic species in the landfill gas, including trimethylarsine and trimethylbismuth, and, for the first time, butyltrimethyltin and dibutyldimethyltin. The presence of molybdenum hexacarbonyl was confirmed. Gas from a large‐scale compost heap and from compost incubated in the laboratory contained iodomethane but no common VOMCs (GC–ICP‐MS). Only VOCs were present in forest air (GC–MS). Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
66.
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   
67.
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   
68.
A critical analysis of the Suzuki, Shanker, and Kumar formulations is presented by studying different classes of materials under high pressure. A similar trend for all the materials studied in the present work, demonstrates that Suzuki formulation is not capable to yield compression behaviour of solids. The Shanker formulation improves the results obtained by the Suzuki formulation in small compression range (0.9<V/V0<1). For further compressions Shanker formulation also fails. On the other hand, the Kumar formulation is found to work well for the entire range of pressure. The reasons for the failure of Suzuki and Shanker formulations are discussed.  相似文献   
69.
The experimental and analytical method of the high-pressure powder experiment at BL10XU, SPring-8, is described. There is no doubt that BL10XU must be one of the most appropriate beam lines for high pressure X-ray diffraction experiment taking advantage of third generation synchrotron source. As an example of the advanced charge density study under high pressure, the structural change of Cs2Au2Br6 by applying pressure is studied by Rietveld/MEM analysis. It reveals that the structural change of Cs2Au2Br6 by applying pressure occurs basically at electron level, such as valence state change and chemical bonding, which may be called the electronic phase transition.  相似文献   
70.
Experimental results are reported for a unique spectroscopic device called the Plasma Spectroscopy Cell. Optical absorption of lithium metal vapor was observed at high density and temperature. Absorption spectra are analyzed using theoretical calculations of absorption cross sections for lithium-helium interactions, and singlet and triplet state transitions of diatomic lithium in the visible spectral range. This is believed to be the most complex example yet calculated in which absolute bound-bound, bound-free, free-bound, and free-free contributions for all possible optically allowed transitions are all included, in quite respectable agreement with experiment.  相似文献   
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