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41.
在介绍“铝丝印”概念的基础上,从金属腐蚀学的观点出发,分析了“铝丝印”形成的电化学腐蚀机理,并提出了具体的解决措施。 相似文献
42.
A. Vahid Shahidi I. Shih T. Araki C. H. Champness 《Journal of Electronic Materials》1985,14(3):297-310
Structural investigation on monocrystalline CuInSe2 samples has been made. From the single crystal results, the space group of CuInSe2 was confirmed to be Iˉ42d and the crystal solidification direction was investigated. Compositional uniformity of the ingots
was established by EPMA and it was found that the indium concentration was greater than that for copper. Systematic annealing
experiments were carried out in vacuum at different temperatures (as low as 160° C) and for different times. Large variation
in resistivity was observed after the annealing treatment. P-type samples were found to convert to n-type after the heat-treatments. 相似文献
43.
介绍煤炭码头带式输送机联锁控制系统设计的一种方法,详细阐述了整个系统的工艺流程、启动方式以及控制原理等。这种方法可以实现带式输送机远程中控室控制,也可进行就地带式输送机机侧控制。 相似文献
44.
E. N. Aleksandrov 《Combustion, Explosion, and Shock Waves》2006,42(2):131-139
An analysis of papers on hydrogen combustion at low pressures is performed, which refines the contribution of the catalytic
reactions on the reactor wall to the gas-phase part of the process. A new model for the heterogeneous loss of active reaction
centers was proposed and tested experimentally to explain inconsistencies that occur in some papers. In this model, the diffusion
region of chain termination is formed under standard experimental conditions in vacuum oxyhydrogen flames at a reactor gas
pressure a thousand times lower than the boundary pressure postulated by the previous models as the pressure below which the
diffusion region of chain termination cannot be formed.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 2, pp. 10–18, March–April, 2006. 相似文献
45.
46.
Somsak Vanit-Anunchai Jonathan Billington Guy Edward Gallasch 《International Journal on Software Tools for Technology Transfer (STTT)》2008,10(1):29-56
State space explosion is a key problem in the analysis of finite state systems. The sweep-line method is a state exploration
method which uses a notion of progress to allow states to be deleted from memory when they are no longer required. This reduces
the peak number of states that need to be stored, while still exploring the full state space. The technique shows promise
but has never achieved reductions greater than about a factor of 10 in the number of states stored in memory for industrially
relevant examples. This paper discusses sweep-line analysis of the connection management procedures of a new Internet standard,
the Datagram Congestion Control Protocol (DCCP). As the intuitive approaches to sweep-line analysis are not effective, we
introduce new variables to track progress. This creates further state explosion. However, when used with the sweep-line, the
peak number of states is reduced by over two orders of magnitude compared with the original. Importantly, this allows DCCP
to be analysed for larger parameter values.
Somsak Vanit-Anunchai was partially supported by an Australian Research Council Discovery Grant (DP0559927) and Suranaree
University of Technology.
Guy Edward Gallasch was supported by an Australian Research Council Discovery Grant (DP0559927). 相似文献
47.
介绍了地线的干扰机理以及减小地线干扰的对策和接地的基本方法.在电子电路中,地线不仅为电路提供一个电位公共参考点,而且也为电流提供一条能够流回源的低阻抗路径.由于地线存在阻抗,当电流流过地线时,会在地线上产生电压差,从而形成地线干扰,严重时将会影响电路的正常工作.减小或消除地线干扰的主要方法是减小地线的阻抗和地线电流.为此,可以针对不同的信号频率及干扰性质,根据系统的结构和功能采用相应的接地方式,将接地、屏蔽及滤波等措施结合使用. 相似文献
48.
Several types of reinforced Nb3Sn wires have been developed to prevent reduction of superconducting properties by applying a strong electromagnetic force. To fabricate a cryocooled magnet using those reinforced wires, we experimentally measured the minimum quench energy (MQE) under cryocooled conditions of some reinforced Nb3Sn wires. As a result, it became clear that thermal stability expressed as MQE was controlled by the temperature margin between the temperature of the operating condition and the transition temperature from superconductivity to normal. Using the FEM analysis, it was realized that the cause of the decline in thermal stability for the reinforced wires was the low thermal conductivity of the reinforced materials. 相似文献
49.
SVK8 3S型氮气压缩机是由沈阳鼓风机厂制造、为义马煤气配套的低压氮气压缩机 ,共两套 ,于 2 0 0 0年 1 2月开始调试。为节约工程基建资金 ,取消原设计两台中压氮气压缩机 ,由杭氧产两台3TYS89+2TYS60型氧气透平压缩机临时压送氮气 ,向外供中压氮 ,来取代中压氮气压缩机 ,流程示意图如图 1所示。图 1 氧、氮压机工艺流程配置图1 事故情况2 0 0 0年 1 2月 2 7日中午 1 1∶3 5 ,接总调度室通知 ,要求中午 1 2∶0 0向长输管线供中压氮气。当时 ,一台氮压机试车完毕正在运行 ,一台氧压机试车完毕压氧正在运行 ,将由氧压机临时压送氮气外供… 相似文献
50.