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191.
在科技文献中,地震常被比喻为非线性动力学过程或统计物理中的相变过程.文章探讨了如何从非线性力学中的分岔理论以及统计物理内的朗道相变理论出发,从势磊穿越,临界涨落与临界慢化等多个角度来分析和了解地震发生的全过程.文章作者试图在这些非线性力学与统计物理的基础上,综合地震过程中在时间与空间上应出现的前兆,解释如何可能做出具有普适性的数值地震预测. 相似文献
192.
Ultrafast internal conversion dynamics of 2-chloropyridine were studied by femtosecond time-resolved photoelectron imaging spectroscopy coupled with time-resolved mass spectroscopy. The ultrafast internal conversion from the second excited state (S2) to the first excited state (S1) via an adjacent conical intersection within (162±5) fs was clearly observed from the time-dependence of the photoelectron spectra. The subsequent deactivations involved the coupling of S2/S0(the ground state) and S1/S0 conical intersections, which occurred on a timescale of about (5.5±0.3) ps, and led to the internal conversion to the ground state from the S2 and S1 states. 相似文献
193.
基于可再生能源配额的政策背景,本文构造了发电商三种不同市场权力结构下的绿色生产决策模型。讨论了敏感参数对异质权力发电商最优决策结果的影响,基于参数范围分析了不同权力结构下的最优决策效果。通过消费者效用、发电成本、环境保护的社会福利函数,识别出了参数最优取值范围内的最优决策效果的市场结构。结果显示:当绿证交易价格、最低配额比例超过最低临界值时,绿色发电商能够实现最优决策效果,但对传统发电商的最大利润产生了显著的“挤出”效应。若绿证交易价格和电力需求价格弹性系数在最佳区间内,则传统和绿色发电商既能够达到最优决策效果,又可以最大限度促进社会福利效用的单调增加,即存在绿色发电商主导的最优市场决策结构,但不存在最优纳什决策结构。 相似文献
194.
SONG RuiBo DAI FuPing & WEI BingBo* Department of Applied Physics Northwestern Polytechnical University Xi’an China 《中国科学:物理学 力学 天文学(英文版)》2011,54(5):901
Rapid solidification of binary Cu-22%Sn peritectic alloys and Cu-5%Sn-5%Ni-5%Ag quaternary alloys was accomplished by glass fluxing, drop tube and melt spinning methods. The undercooled, by glass fluxing method, Cu-22%Sn peritectic alloy was composed of α(Cu) and δ(Cu41Sn11) phases. If rapidly solidified in a drop tube, the alloy phase constitution changed from α(Cu) and δ(Cu41Sn11) phases into a single supersaturated (Cu) phase with the reducing of droplet diameter, and the maximum solubility of Sn in (Cu)... 相似文献
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Rui Nian HUA Zhi Hong JIA De Min XIE Chun Shan SHI* Faculty of Chemistry Northeast Normal University Changchun Key Laboratory of Rare Earth Chemistry Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Ch 《中国化学快报》2002,13(10)
The complex fluoride LiBaF3 is solvothermally synthesized at 180℃ and characterized by means of X-ray powder diffraction, scanning electron microscopy, thermogravimetric analysis and infrared spectroscopy. In the solvothermal process, the solvents, mole ratios of initial mixtures and reaction temperature play important roles in the growth of the single crystal. 相似文献
198.
Wei Ming ZHU Hong Ping HE Song WANG Guo Ying ZUO Xiao Jiang HAO* Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming Department of Chemistry Yunnan Normal University Kunming 《中国化学快报》2002,13(3)
Elsholtzia bodinieri Vant (Labiatae) named Feng-Wei-Cha or Dong-Zi-Su, is a Chinese medicinal plant, which is distributed in Yunnan and Guizhou Province of China. It is used in treatment of cough, headache, pharyngitis, fever and heptatitis1. In order to seek for the relative bioactive components, we studied the chemical constituents of E. bodinieri, which have not been reported in the literature. Two new triterpenoid glycosides, hederagenin-3-O-b-D-xylopyranoside (1), dodecandral-3-O… 相似文献
199.
Wei WANG Jun Cheng LIU Pei Ji GAO* The State Key Laboratory of Microbial Technology Shandong University Jinan School of Chemical Environmental Engineering Jinan University Jinan Institute of Colloidal Interface Chemist 《中国化学快报》2002,13(8):773-776
Cellulose is the most abundant resource of regenerative biomass on earth. But due to the complexity of its structure, its degradation mechanism was failed to fully understand. It makes a great limit to its full utility. In nature, wood decay is mainly accomplished by some wood-degrading fungi such as G.trabeum et al.. It is well-known that cellulases are the most important components of degrading cellulose. But because the cellulase activity is low, the complete utility of cellulose by e… 相似文献
200.
Hai Tao YU Wan Xuan ZHANG Wu Xin ZHOU Teruo MASTUURA Ji Ben MENG* Department of Chemistry Nankai University Tianjin Emeritus Professor of Kyoto University Kyoto - Japan 《中国化学快报》2002,13(10)
Since Tang and Van Slyke reported the first double-layer organic electroluminescent (EL) device using Alq3 (q = 8-hydroxyquinolinyl) in 19871, organic EL devices have received a great deal of attention in view of their application as full-color flat-panel displays as well as academic interest2,3,4. There have been extensive studies of organic EL devices directed toward achieving high brightness and multi- or full-color emission, and in particular, improving the durability and thermal stabi… 相似文献