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排序方式: 共有1683条查询结果,搜索用时 15 毫秒
91.
This paper is focus on the corrosion resistance property analysis on three electric blasting of the coating-FeAl,FeCrAl,FeCrAlRE by electrochemical noise technology,acceleration of copper acetate salt spray accelerated corrosion test.According to a comparative analysis of three tests coated by the Impedance curve,FeCrAlRE coating power spectral density(SPD)curve and Power curve,FeAl,FeCrAlRE coating has two more notable for the corrosion resistance properties than FeAl,FeCrAl coatings. 相似文献
92.
The effective parameters on the diameter of carbon nanotubes (CNTs) by plasma enhanced chemical vapor deposition (PECVD) were presented.Among lots of influential parameters,the effects of the catalytic film thickness and the pretreatment plasma power on the growth of CNTs were investigated.The results show that the size of catalytic islands increases by increasing the thickness of catalytic layer,but the density of CNTs decreases.The pretreatment duration time of 30 s is the optimal condition for growing CNTs with about 50 nm in diameter.By increasing the pretreatment plasma power,the diameter of CNTs decreases gradually.However,the diameter of CNTs does not change drastically from 80 to 120 W.The uniformly grown CNTs with the diameter of 50 nm are obtained at the pretreatment plasma power of 100 W. 相似文献
93.
A composite Ni based MoS2 solid lubrication coating was prepared using the plasma spraying technology with optimized process parameters.The tribological properties of the composite Ni/MoS2 coatings in air and vacuum were studied with a ball-on-disk friction and wear tester under dry sliding condition,respectively.XRD,SEM and EDS were adopted to analyze the microstructures of the coating before and after wear tests.Results showed that the deposition quality of the coating was good.The content of lubricant MoS2 was high.But the compactability of the coating with many superficial micrometersized defects such as pores and cracks was relatively low.The composite Ni/MoS2 coating exhibited excellent friction-reduction properties both in air and in vacuum conditions.In vacuum,the wear loss was greater because the severe spalling of top layer resulted from breakthrough of the adjacent defects.In air condition,the wear loss of the coating was relatively low but its friction-reduction ability may be weakened for the oxidation of MoS2. 相似文献
94.
Yu-Gang Miao Ben-Shun Zhang Bin-Tao Wu Xiao-Xiao Wang Guang-Yu Chen Duan-Feng Han 《金属学报(英文版)》2016,(4):360-366
Sheets of aluminum 6061 alloy were welded using bypass-current double-sided arc welding with Al–Si filler wire to investigate the effect of Al–Si intermetallic compounds on the microstructure, microhardness and corrosion behavior of weld joint. Experimental results indicated that the Al_(4.5)FeSi phase in the topside of the weld joint was finer than that in the backside and newly formed phase of Al_(0.5)Fe_3Si_(0.5)was observed in the backside. The formation of reinforcing phases of Al–Fe–Si in the weld improved the microhardness of the weld by about 18%. The corrosion resistance of the weld zone was greater than that of the base metal, while the corrosion current displayed opposite, and the corrosion resistance of the weld region was better than that of the base metal. 相似文献
95.
本文应用 PKA 微量滴定板方法,用 WHO1984年建立的 PKA 国际标准品进行标定,制备了我国第一批 PKA 国家参考品。 相似文献
96.
我们对新配方吸附及不吸附的百白破混合制剂进行了人群使用反应及效果观察。结果表明,免疫效果前者优于后者,免疫反应前者较明显低于后者,这为修订规程,统一配方及提高制品质量提供了依据。观察中吸附制品的无菌化脓率为0.29%。 相似文献
97.
作者应用ELISA,连续7年对本所动物繁育场、部分省市药厂、防疫等部门的各级鼠群进行了MHV抗体检测,发现MHV感染非常普遍。对病原的分离和鉴定证明,所分离的病原物确系MHV。作者还对MHV的垂直传播进行了探讨。 相似文献
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