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新法浸铈氨合成催化剂 总被引:1,自引:1,他引:1
新法浸铈氨合成催化剂秦春玲关新新王茹胡平聂聪王文祥*(郑州大学催化研究室郑州450052)关键词熔铁催化剂,浸铈,氨合成,活性,强度1997-03-19收稿,1997-08-12修回国家自然科学基金资助课题铈作为氨合成催化剂的一种添加剂能提高催化活性... 相似文献
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本文报道利用光波导方法在GaAs衬底上制备的Ⅱ-Ⅵ族半导体单晶薄膜和超晶格中所观测到的光学吸收,光学非线性和瞬态光学双稳的实验结果。 相似文献
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A full experimental characterization of mechanically induced long-period fiber gratings (MLPFGs) fabricated by pressing a plate with periodic grooves against a short length of fiber is presented. This technique enables a good control over the gratings' isolation loss peaks and has high repeatability. The spectra characteristics of MLPFGs are studied with the change of the parameters including pressure, period, and temperature. The produced MLPFGs have low insertion loss (〈 0.2 dB) and the loss peaks can be higher than 20 dB. A large tunability of the resonant wavelength (〉 14 nm) is achieved through adjusting pres- sure grooves' period. The center wavelength temperature sensitivities of 0.057, 0.086 nm/℃, and resonant peak temperature sensitivities of 0.230, 0.312 dB/℃, are achieved for jacketed and unjacketed fibers, respectively. These MLPFGs, which are simple and inexpensive, also offer the unique advantages of being tunable, erasable, and reconfigurable. 相似文献
266.
NECESSARY AND SUFFICIENT CONDITIONS FOR OSCILLATIONS OF HYPERBOLIC AND ELLIPTIC TYPE PARTIAL DIFFERENCE EQUATIONS 总被引:2,自引:0,他引:2
1 IntroductionQualitative theory for discrete dynamics systems with 1-D, that is, forordinary delay difference equation which is parallel to the qualitative theoryof ordinary delay differential equations has been investigated by a number ofauthors in recent years. Some of the results obtained have been collected inthe book by Gy6ri and Ladas [1, Chapter 7]. While nonlinear discrete dynamics systems with 2-D, that is, delay partial difference equations are equallyimportant in terms of physica… 相似文献
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关于微泵的研制起始于20世纪80年代[1],现已研制开发出很多种类的微泵,如可以用多种驱动力驱动的机械微泵(压电驱动、静电驱动和热气动力驱动等)[2]和以场感应流微泵为主的非机械微泵(包括电渗泵、磁液态动力泵和电液态动力泵等[3]).机械微泵的制造工艺复杂,而且液流有脉动性;场感应流微泵的液流无脉动性,流速范围可在每分钟几纳升到每分钟几百微升之间变化,因此被微流控系统广泛采用,但这种微泵需要庞大的驱动器,使用不便. 相似文献
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The main goal of this paper is to design a team of agents that can accomplish multi-target pursuit formation using a developed leader--follower strategy. It is supposed that every target can accept a certain number of agents. First, each agent can automatically choose its target based on the distance from the agent to the target and the number of agents accepted by the target. In view of the fact that all agents are randomly dispersed in the workplace at the initial time, we present a numbering strategy for them. During the movement of agents, not every agent can always obtain pertinent state information about the targets. So, a developed leader--follower strategy and a pursuit formation algorithm are proposed. Under the proposed method, agents with the same target can maintain a circle formation. Furthermore, it turns out that the pursuit formation algorithm for agents to the desired formation is convergent. Simulation studies are provided to illustrate the effectiveness of the proposed method. 相似文献