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951.
��˴������ Ⱥ���ӷ��� 《核聚变与等离子体物理》2006,38(4):386-393
The high speed CCD visible-light camera system has been installed to detect the dynamic characteristics of ELMs filaments on EAST tokamak. In order to convert the CCD video imaging coordinates into real space coordinates, the CCD system has calibrated using Tsai’s two-stage calibration technique. A raised spike in the grayscale profile, drawn by selecting the grayscale value of the image in the vertical direction of the ELMs filament in the CCD image, represents an ELMs filament structure whose positional coordinates are determined by the apex of the spike. The Sobel edge detection operator was used to examine the edge profile of the filament to obtain the width of the filament. By analyzing the characteristics of the filament width of the ELMs, it is found that the width of ELMs filaments continuously decreases outward from the outermost magnetic surface. This indicates that the filaments continue to dissipate energy and particles as they propagate outward. The width of filaments of Type-I ELMs is greater than that of Type-III ELMs. 相似文献
952.
进行了百万大气压下,静水压和非静水压条件下的压力校准,同时观察到金刚石砧容器中红宝石R线红移至830nm处,由校准公式算得对应的压强为5.5Mbar。
关键词: 相似文献
953.
954.
Summary Pharmaceutical products have to be tested for impurities including residual solvents. This is also required in production control. The simplest solution to this problem is headspace gas chromatography. This paper describes the determination of residual volatile hydrocarbons in the transdermal system DEPONIT by only one headspace measurement. Accuracy is ensured by the multiple headspace extraction technique.
Bestimmung von Restlösungsmittelgehalten in einem transdermalen System durch Headspace-Gas-Chromatographie
Zusammenfassung Pharmazeutische Produkte müssen auf Verunreinigungen geprüft werden, auch auf Restlösungsmittelgehalte. Ein zusätzlicher Grund ist die fortlaufende Kontrolle der Herstellung. Die einfachste Möglichkeit für dieses Problem ist die Bestimmung durch Headspace-Gas-Chromatographie. Dieser Artikel beschreibt die Bestimmung von noch vorhandenen flüchtigen Kohlenwasserstoffen in dem transdermalen System DEPONIT durch nur eine Headspace-Messung. Die Richtigkeit ist durch die Anwendung der Mehrfach-Gasextraktionstechnik sichergestellt.相似文献
955.
The mode equation for the dielectric waveguide with parabolic cross-section is derived using both the effective index method and WKB theory, and the expression of the mode propagation constant or effective index is solved directly from this mode equation, so that the mode-propagation properties of this kind of waveguide can be analysed conveniently with comparative accuracy. 相似文献
956.
957.
If g and G are the pdf and the cdf of a distribution symmetric around 0 then the pdf 2g(u)G(λ
u) is said to define a skew distribution. In this paper, we provide a mathematical treatment of the skew distributions when
g and G are taken to come from one of Pearson type II, Pearson type VII or the generalized t distribution.
相似文献
958.
Xie Zhijian Tan Qiulin 《International Journal of Infrared and Millimeter Waves》2006,27(12):1639-1649
To counter the problems of gas accidents in coal mines, family safety resulted from using gas, a new infrared detection system
with integration and miniaturization has been developed. The infrared detection optics principle used in developing this system
is mainly analyzed. The idea that multi gas detection is introduced and guided through analyzing single gas detection is got
across. Through researching the design of cell structure, the cell with integration and miniaturization has been devised.
The way of data transmission on Controller Area Network (CAN) bus is explained. By taking Single-Chip Microcomputer (SCM)
as intelligence handling, the functional block diagram of gas detection system is designed with its hardware and software
system analyzed and devised. This system designed has reached the technology requirement of lower power consumption, mini-volume,
big measure range, and able to realize multi-gas detection. 相似文献
959.
The possible defect models of Y^3+:PbWO4 crystals are discussed by defect chemistry and the most possible substituting positions of the impurity Y^3+ ions are studied by using the general utility lattice program (GULP). The calculated results indicate that in the lightly doped Y^3+ :PWO crystal, the main compensating mechanism is [2Ypb^+ + VPb^2-], and in the heavily doped Y^3+ :PWO crystal, it will bring interstitial oxygen ions to compensate the positive electricity caused by YPb^+, forming defect clusters of [2Ypb^+ +Oi^2-] in the crystal. The electronic structures of Y3+ :PWO with different defect models are calculated using the DV-Xα method. It can be concluded from the electronic structures that, for lightly doped cases, the energy gap of the crystal would be broadened and the 420nm absorption band will be restricted; for heavily doped cases, because of the existence of interstitial oxygen ions, it can bring a new absorption band and reduce the radiation hardness of the crystal. 相似文献
960.
用核磁共振对非晶态中B3+离子的微观结构进行了测定,结合Raman光谱的研究,对Li2O-B2O3-P2O5系统非晶态的性能(电导率、密度等)在P2O5/B2O3比约等于1时产生极值的原因从理论上作了阐明。 相似文献