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排序方式: 共有3514条查询结果,搜索用时 15 毫秒
991.
In this paper, by using the stability theory of stochastic
differential equations, the average-consensus problem with noise
perturbation is investigated. It is analytically proved that the
consensus could be achieved with a probability of one. Furthermore,
numerical examples are taken to illustrate the effectiveness of the
theoretical result. 相似文献
992.
The multi-phase particle swarm optimization (MPPSO) technique is applied to retrieve the particle size distribution (PSD) under dependent model.Based on the Mie theory and the Lambert-Beer theory, three PSDs, i.e., the Rosin-Rammer (R-R) distribution, the normal distribution, and the logarithmic normal distribution, are estimated by MPPSO algorithm.The results confirm the potential of the proposed approach and show its effectiveness.It may provide a new technique to improve the accuracy and reliability of the PSD inverse calculation. 相似文献
993.
An approach of open-path gas sensor based on tunable diode laser absorption spectroscopy 总被引:1,自引:0,他引:1
Hui Xia Wenqing Liu Yujun Zhang Ruifeng Kan Min Wang Ying He Yiben Cui Jun Ruan Hui Geng 《中国光学快报(英文版)》2008,6(6)
Tunable diode laser absorption spectroscopy (TDLAS) is a new method to detect trace-gas qualitatively or quantificationally based on the scan characteristic of the diode laser to obtain the absorption spectroscopy in the characteristic absorption region. A time-sharing scanning open-path TDLAS system using two near infrared distributed feedback (DFB) tunable diode lasers is designed to detect CH4 and H2S in leakage of natural gas. A low-cost Fresnel lens is used in this system as receiving optics which receives the laser beam reflected by a solid corner cube reflector with a distance of up to about 60 m. High sensitivity is achieved by means of wavelength-modulation spectroscopy with second-harmonic detection. The minimum detection limits of 1.1 ppm·m for CH4 and 15 ppm·m for H2S are demonstrated with a total optical path of 120 m. The simulation monitoring experiment of nature gas leakage was carried out with this system. According to the receiving light efficiency of optical system and detectable minimum light intensity of detection, the detectable optical path of the system can achieve 1 - 2 km. The sensor is suitable for natural gas leakage monitoring application. 相似文献
994.
分析了加固型可摄重写分离式光学头的基本工作原理。着重讨论了光学头的设计、研制及相关技术,得到了若干有实用价值的结论。 相似文献
995.
Ruan Shigui 《咸宁学院学报》1991,(1)
Liapunov functionals of simple form have been used to de-rive new sufficient conditions for uniform asymptotic stability of the zero so-lution of linear neutral differential difference systems. 相似文献
996.
用气相输运平衡技术成功地制备出了近化学计量组分的Er∶LiNbO3晶体,系统 地研究了该 晶体的吸收边移动、可见—红外透射谱、荧光光谱的物理特性.与同成分Er∶LiNbO3 sub>晶体 相比, 近化学计量组分Er∶LiNbO3晶体的吸收边出现了“蓝移”;OH- sup>吸收带明显减弱 ;在可见—近红外波段呈现出更高的透过率;同时Er3+离子的发光强度也明显 提高. 这些结果表明近化学组分的Er∶LiNbO关键词:
近化学组分掺铒铌酸锂晶体
- 吸收带')" href="#">OH-吸收带
透射谱
荧光光谱 相似文献
997.
D. Ackermann S. Antalic M. Axiotis D. Bazzacco S. Beghini G. Berek L. Corradi G. De Angelis E. Farnea A. Gadea F. P. Heßberger S. Hofmann M. G. Itkis G. N. Kniajeva E. M. Kozulin A. Latina T. Martinez R. Menegazzo G. Montagnoli G. Münzenberg Yu. Ts. Oganessian C. Rossi-Alvarez M. Ruan R. N. Sagaidak F. Scarlassara A. M. Stefanini S. Szilner M. Trotta C. Ur 《The European Physical Journal A - Hadrons and Nuclei》2003,20(1):151-152
To study basic properties of the fusion reaction dynamics for heavy compound systems the partial-wave distribution
can be employed as an alternative to the classically used fusion/fission excitation functions. A variety of reactions leading to compound nuclei (CN) in the Pb region can be used to investigate features like the fusion-fission competition, the role of deformation in the fusion of heavy systems and a possible effect of the Z = 82 shell on the enhancement of evaporation residue (ER) production.Received: 5 November 2002, Revised: 26 March 2003, Published online: 9 March 2004PACS:
24.75. + i General properties of fission - 25.70.Gh Compound nucleus - 25.70.Jj Fusion and fusion-fission reactions 相似文献
998.
Zhijun Zhang 《Journal of Mathematical Analysis and Applications》2005,312(1):33-43
By Karamata regular variation theory and constructing comparison functions, we show the exact asymptotic behaviour of the unique classical solution near the boundary to a singular Dirichlet problem −Δu=k(x)g(u), u>0, x∈Ω, u|∂Ω=0, where Ω is a bounded domain with smooth boundary in RN; g∈C1((0,∞),(0,∞)), , for each ξ>0, for some γ>0; and for some α∈(0,1), is nonnegative on Ω, which is also singular near the boundary. 相似文献
999.
Xinqi Ma Caixia Feng Zhensheng Jin Xinyong Guo Jianjun Yang Zhijun Zhang 《Journal of nanoparticle research》2005,7(6):681-683
A new method for preparing PtO x -inserted sodium titanate nanotube was reported. By suction of H2PtCl6 ethanol solution into the nanotubes first and annealed at 653 K for 3 h afterwards, Pt nanoparticles formed in the nanotubes. The size of Pt nanoparticles is controlled by the dimensions of nanotubes. Some of them are spherical, some are nanorods. XPS and XRD results revealed that during annealing the following complex reaction happened:
相似文献
$Na_1.1H_0.9Ti_2O_4(OH)_2 + H_2PtCl_6+ O_2 \rightarrow TiO_2(anatase) + PtO_x(x=1,2)+NaCl+ HCl\!\uparrow\!\!.$
1000.