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31.
采用固体Nd:YAG激光器对离子镀TiN薄膜进行织构化处理,表征了薄膜的结构、形貌及凹坑织构参数.通过UMT-2往复式球-盘摩擦磨损试验机评价了织构化薄膜的摩擦磨损特性,研究了织构形貌对TiN薄膜干摩擦条件下摩擦磨损性能的影响.研究结果表明:与未织构化的TiN薄膜相比,织构化TiN薄膜的平均摩擦系数降低,并且磨损率明显减小,这说明织构化TiN薄膜具有更好的耐磨损性能.摩擦过程中,凹坑织构既捕获了磨屑,又有利于摩擦过程中阶跃运动的发生,易于将磨屑带出磨痕,从而降低了摩擦磨损. 相似文献
32.
Fe/MnO-ZnZSM-5双功能催化剂上合成气直接转化为芳烃的反应 总被引:4,自引:0,他引:4
探讨了Fe/MnO-ZnZSM-5(n(SiO2)/n(Al2O3)=50)双功能催化剂上合成气直接转化为芳烃的反应,考察了反应温度和Zn载量对CO转化率及芳烃选择性的影响.结果表明,Fe/MnO-ZnZSM-5具有良好的合成气芳构化性能,在V(CO)∶V(H2)∶V(Ar)=3∶6∶1,SV=1600h-1,p=1.1MPa,T=543K的条件下,CO转化率可达到98.1%,芳烃产物选择性可高达53.1%.催化剂经60h运转后,CO转化率仅降低0.5%,显示了良好的稳定性和应用前景. 相似文献
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Structures of an asymmetrically coupled double-well superlattice by double-crystal X-ray diffraction
An asymmetrically coupled (GaAs/AlAs/GaAs/AlAs)/GaAs (001) double-well supperlattice is studied by HRDCD (high resolution
double-crystal X-ray diffractometry). The intensity of satellite peaks is modulated by wave packet of different sublayers.
In the course of simulation, the satellite peaks in the vicinity of the node points of wave packet are very informative for
precise determination of sublayer thickness and for improving accuracy. 相似文献
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36.
A new dynamic Data Envelopment Analysis (DEA) approach is created to provide valuable managerial insights when assessing the
merger performance. This new approach allows us to dynamically evaluate the pre-merger firms and the post-merger firm in a
multi-period situation. A case study of bank branch merger is conducted to illustrate and validate the proposed approach.
Both stochastic frontier analysis and data envelopment analysis are used and compared leading to highly correlated results.
The computation show that merger results in an overall efficiency achievement in a banking industry. 相似文献
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38.
Desheng Wu 《Central European Journal of Operations Research》2011,19(1):99-137
This paper investigates the equilibrium behavior of a two-echelon supply chain in four channel strategies: (i) vertical integration,
(ii) vertical Nash (iii) manufacturer’s Stackelberg and (vi) retailer’s Stackelberg. We examine the price and service level
decision for each of the above four channel strategies in two cases: (i) Simultaneous service-level decision: Here, the manufacturer
and retailer simultaneously choose a service level. (ii) Sequentially service-level decision: Here, the manufacturer and retailer
sequentially choose a service level. We model the demand as a deterministic linear function of retailer’s price and both manufacturer’s
and retailer’s service levels. We discuss the optimal configuration from each individual’s perspective for each of the above
channel strategies. We show that vertical integration dominates other strategies and leads to the highest service level but
lowest retail price among various channel coordination policies considered here. We yield several conclusions about the provision
of service level by each supply chain individual to coordinate the channel. 相似文献
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