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71.
Thomson散射诊断技术的新进展 总被引:1,自引:0,他引:1
Thomson散射是一种主动而无干扰地对等离子体进行诊断的方法.它能够以较高的时空分辨率测量等离子体的参数,如电子与离子温度、密度以及等离子体的膨胀速度、电离程度、热流等参数.文章从Thomson散射基本概念出发,介绍了Thomson散射诊断方法在研究激光与等离子体相互作用中的重要意义,并分别介绍了近年来Thomson散射诊断技术的新进展,如对高Z等离子体、两种离子种类的等离子体、多种形态等离子体以及高密度等离子体的研究.文章最后对国内Thomson散射诊断技术的发展状况进行了简述. 相似文献
72.
73.
It is shown that in magnetically quantized plasmas, static Debye screening is changed. Furthermore, it is shown that under
special circumstances, two electrons in such media may attract each other.
Article presented at the International Conference on the Frontiers of Plasma Physics and Technology, 9–14 December 2002, Bangalore,
India. 相似文献
74.
S. Djenie A. Srekovi S. Bukvi 《Spectrochimica Acta Part B: Atomic Spectroscopy》2005,60(12):1552-1555
The Stark widths (W) and shifts (d) of two neutral (520.908 and 546.550 nm), eleven singly (211.382, 224.643, 224.874, 232.029, 232.468, 233.140, 241.141, 241.323, 243.781, 244.793 and 276.754 nm) and three doubly (216.189, 231.004 and 239.569 nm) ionized silver (Ag I, Ag II and Ag III, respectively) spectral lines have been measured in nitrogen plasma at about 18,000 K electron temperature and electron density ranged between 0.65 × 1023 and 1.15 × 1023 m− 3. They are the first measured W and d values while those of the Ag II and Ag III lines are the first published data in these spectra. The modified version of the linear, low-pressure, pulsed arc was used as a plasma source operated in nitrogen with silver atoms, as impurities, evaporated from silver cylindrical plates located in the homogeneous part of the discharge. No theoretical predictions exist for W and d values of above mentioned spectral lines. Besides, we have checked the transition probability ratio of two investigated Ag I lines. An agreement with theoretical predictions was found. 相似文献
75.
It has been shown that pressure waves can have a large effect on the burning rate of flames. In this paper, the evolution
of convection-driven fast flame, which is acoustically linked to a shock wave via an induction zone, is examined in detail.
It is found that there is positive feedback mechanism and the asymptotic model breaks down as blow up occurs. Comparison
is made between the case of a piston driving a shock wave into a combustible atmosphere with these studies of a shock wave
passing through an existing premixed flame.
Received 4 August 1995 / Accepted 20 March 1996 相似文献
76.
This study is devoted to analysis of semi-implicit compact finite difference (SICFD) methods for the nonlinear Schrödinger equation (NLS) perturbed by the wave operator (NLSW) with a perturbation strength described by a dimensionless parameter ε∈(0,1]. Uniform l∞-norm error bounds of the proposed SICFD schemes are built to give immediate insight on point-wise error occurring as time increases, and the explicit dependence of the mesh size and time step on the parameter ε is also figured out. In the small ε regime, highly oscillations arise in time with O(ε2)-wavelength. This highly oscillatory nature in time as well as the difficulty raised by the compact FD discretization make establishing the l∞-norm error bounds uniformly in ε of the SICFD methods for NLSW to be a very interesting and challenging issue. The uniform l∞-norm error bounds in ε are proved to be of O(h4+τ) and O(h4+τ2/3) with time step τ and mesh size h for well-prepared and ill-prepared initial data. Finally, numerical results are reported to verify the error estimates and show the sharpness of the convergence rates in the respectively parameter regimes. 相似文献
77.
Xerardo García-Mera José E. Rodríguez-Borges M. Luísa C. ValeMaria J. Alves 《Tetrahedron》2011,67(37):7162-7172
The cycloaddition between protonated glyoxylate imines possessing two chiral auxiliaries, N-(S)- or N-(R)-1-phenylethyl and (−)-8-phenylmenthyl or (+)-8-phenylneomenthyl, and cyclopentadiene is described. The absolute configuration of all adducts formed was unequivocally assigned through NMR, specific optical rotation, and X-ray data of appropriated derivatives. Experimental results confirm the highly exo-selectivity for these aza-Diels-Alder reactions, single adducts being obtained from combinations of (8PM)-(R-PEA) and (8PNM)-(S-PEA). 相似文献
78.
79.
Christophe Pallard 《Mathematical Methods in the Applied Sciences》2011,34(7):803-806
We consider the initial value problem for the classical Vlasov–Poisson system with smooth compactly supported initial data. In the electrostatic case, we show that the size of the velocity support of the distribution function grows at most like t2/7+bfε for any ε> 0 . Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
80.