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991.
Y. W. Liu Z. Y. Wang Y. Liu C. X. Wang S. S. Qu F. J. Deng F. J. Li 《Journal of Thermal Analysis and Calorimetry》2001,66(3):903-903
Journal of Thermal Analysis and Calorimetry - 相似文献
992.
D. Mondelain C. Camy-Peyret W. Deng S. Payan A.W. Mantz 《Applied physics. B, Lasers and optics》2008,90(2):227-233
The impact of precise spectroscopic measurements on the P(9) multiplet in the ν3 band of 12CH4, obtained using a newly developed cold Herriott cell coupled with a tunable diode laser spectrometer, is examined in the
context of remote sensing of methane in the atmosphere. More specifically, the influence of the air-broadening temperature
dependence, of line narrowing and of line-mixing effects is assessed when fitting high resolution atmospheric spectra recorded
from a balloon in the solar occultation mode. This is achieved by considering residuals and retrieved methane volume mixing
ratio profiles. By combining data from previous studies together with new measurements, the expression for the temperature
dependence of the broadening coefficient has been revisited. It is shown that a correcting factor applied to the usual law
gives better results, when considering all the available measurements from room temperature down to about 10–20 K, as compared
to the usual expression of the width versus temperature. These results clearly demonstrate that collision broadening is more
sensitive to long-range attractive forces when the temperature is decreased.
PACS 33.70.Jg; 34.20.-b 相似文献
993.
This paper studies an inverse problem of identifying the coefficient of parabolic equation when the final observation is given, which has important application in a large fields of applied science. Based on the optimal control framework, the existence and necessary condition of the minimum for the control functional are established. Since the optimal control problem is nonconvex, one may not expect a unique solution. However, in this paper the solution is proved to be locally unique. After the necessary condition is transformed into an elliptic bilateral variational inequality, an algorithm and some numerical experiments are proposed in the paper. The numerical results show that the algorithm designed in this paper is stable and that the coefficient is recovered very well. 相似文献
994.
舰艇对抗微分对策建模研究 总被引:1,自引:0,他引:1
编队舰艇对抗攻击瞬时运动状态过程的完整描述是一个尚未很好解决的技术难点,本就驱逐舰对多艘导弹快挺对抗攻击建模问题进行了研究,建立了攻击时间尽可能短的定量微分对策模型,并给出了具体实现方法,中模型和方法可为实时舰艇作战指挥系统的研制、开发提供技术支持及理论依据。 相似文献
995.
Kexin Li Yanhong Luo Zhexun Yu Minghui Deng Dongmei Li Qingbo Meng 《Electrochemistry communications》2009,11(7):1346-1349
Porous carbon counter electrodes have been fabricated at low temperature by coating an organic binder free carbon slurry onto F-doped tin oxide conducting glass. The carbon slurry is prepared by ball-milling a dispersion of activated carbon in aqueous SnCl4 solution. During ball-milling, SnCl4 hydrolyzes and transforms into stannic acid gel, which acts as an inorganic “glue” to connect the carbon particles during film preparation. Dye-sensitized solar cells employing this carbon electrode achieve efficiency as high as 6.1% which is comparable to that of the cells using sputtering Pt as counter electrode. 相似文献
996.
Qintao Deng 《Archiv der Mathematik》2008,90(4):360-373
In this paper, we consider complete hypersurfaces in R
n+1 with constant mean curvature H and prove that M
n
is a hyperplane if the L
2 norm curvature of M
n
satisfies some growth condition and M
n
is stable. It is an improvement of a theorem proved by H. Alencar and M. do Carmo in 1994. In addition, we obtain that M
n
is a hyperplane (or a round sphere) under the condition that M
n
is strongly stable (or weakly stable) and has some finite L
p
norm curvature.
Received: 14 July 2007 相似文献
997.
采用体视显微镜和偏光显微镜,对比观察了耀州窑北宋青瓷白色中间层和唐代、五代青瓷化妆土之间的微观结构.结果显示,在体视显微镜下中间层和化妆土层均为白色薄层,但在偏光显微镜下明显可见化妆土层,未见中间层.并探讨了这些现象与二者的化学组成和形成机理的关系. 相似文献
998.
999.
Yue‐Qi Mo Xian‐Yu Deng Xi Jiang Qiu‐Hong Cui 《Journal of polymer science. Part A, Polymer chemistry》2009,47(13):3286-3295
Poly(3,6‐silafluorene) is a typical wide band‐gap conjugated polymer with ultraviolet light emission. The blue electroluminescence from the 3,6‐silafluorene‐based copolymers via intrachain energy transfer was reported in this study. The monomer containing vinylene, anthracene, and tri‐arylamine moieties incorporated into the poly(3,6‐silafluorene) backbone can form efficient deep‐blue emitting copolymers with EL efficiency of 1.1–1.9%. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3286–3295, 2009 相似文献
1000.
This article is contributed to the Cauchy problem u/t = △u K(ㄧxㄧ)up in Rn x (0,T), u(x,0) =(ψ)(x) in Rn; with initial function(ψ)≠0. The stability of positive radial steady state, which are positive solutions of △u K(ㄧxㄧ)up =0, is obtained when p is critical for general K(ㄧxㄧ). 相似文献