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91.
The clinical fertility tests, available in the market, fail to define the exact cause of male infertility in almost half of the cases and point toward a crucial need of developing better ways of infertility investigations. The protein biomarkers may help us toward better understanding of unknown cases of male infertility that, in turn, can guide us to find better therapeutic solutions. Many clinical attempts have been made to identify biomarkers of male infertility in sperm proteome but only few studies have targeted seminal plasma. Human seminal plasma is a rich source of proteins that are essentially required for development of sperm and successful fertilization. This viewpoint article highlights the importance of human seminal plasma proteome in reproductive physiology and suggests that differential proteomics integrated with functional analysis may help us in searching potential biomarkers of male infertility.  相似文献   
92.
高亮  张国钧 《工矿自动化》2012,38(12):87-90
针对选煤厂运煤火车人工喷洒防冻液不均匀的问题,设计了一种基于CC-Link的火车皮防冻液自动喷洒系统。该系统采用CC-Link现场总线技术将多套喷洒装置和防冻液加压泵站构建成工业现场级控制网络,实现了各装置之间的联动和实时监控。实际应用表明,该系统避免了防冻液的浪费,提高了工作效率。  相似文献   
93.
An inductively coupled (ic) radio-frequency (rf) stabilized argon plasma was generated in a quartz tube using a 7 MHzrf generator. The electrical and thermal powers were measured and the efficiency of energy conversion was computed. The results indicate that for a constant power input, there is an optimum argon flow rate for which maximum energy conversion efficiency occurs.  相似文献   
94.
Recent advances in the fabrication of high-T c superconducting thick films demand processing techniques which can eliminate film/substrate interdifiusion that occurs during subsequent post-annealing heat treatment after the film is deposited, thereby limiting the application of the thick films for devices. The present study evaluates laser annealing techniques for plasma-deposited Y-Ba-Cu-O thick films using a high-energy CO2 laser (10.6m) in a continuous wave mode. The results are compared with those obtained by conventional furnace annealing techniques necessary for post-heat treatment of as-deposited superconducting thick films. The high-T c superconducting phase is recovered by cationic diffusion during subsequent post-annealing heat treatment. Crystallographic phases and microstructural characterization have been performed using XRD, SEM, and EPMA analytical techniques. The significance of the technology lies in the elimination of film/substrate interdiffusion problems, thereby resulting in high-quality superconducting thick films. The technology will significantly reduce the post-annealing times usually required by conventional furnace annealing techniques.  相似文献   
95.
We report some preliminary measurement of the erosion rate of plasma dumps when bombarded with 100 keV He+ ions at high power density ( 1 MW/m2). The expected erosion rates, based on measurements of He blistering that were made at lower power density ( 0.3 MW/m2), indicate a potentially serious problem for fusion reactors. Our tests use a reactorlike power density and produce He blisters at a rate that is slower than predicted by 2 to 4 orders of magnitude, depending on the temperature of the molybdenum target.  相似文献   
96.
介绍了等离子电弧加热金属薄板柔性成形的特点,分析了等离子电弧柔性成形的机理.通过实验,得出了扫描次数、电弧电流、扫描速度、电弧高度、薄板厚度等参数对弯曲变形的影响规律.该规律对于提高弯曲效率、改善表面质量具有一定的指导意义.  相似文献   
97.
This work addresses the fabrication of membrane-type solid oxide fuel cells (SOFCs) operating at medium temperatures, where all components are fabricated by plasma spray technology, and the evaluation of the performance of the SOFC single unit in a temperature range of 500 to 800 °C. Single cells composed of LaSrMgO3 cathodes, LaSrGaMgO3 (LSGM) electrolytes, and Ni/yttria-stabilized zirconia anodes were fabricated in successive atmospheric plasma-spraying processes. Plasma-spraying processes have been optimized and tailored to each layer to achieve highly porous cathode and anode layers as well as high-density electrolyte layers. A major effort has been devoted to the production of the LSGM electrolyte that has a high density and is free of cracks. Electrochemical impedance spectroscopy was used to investigate the conductivity of the electrode layers, and particularly the resistance of the electrolyte layer. It revealed that the heat treatment had a great influence on the specific conductivity of the sprayed electrolyte layers and that the specific conductivity of the heat-treated layers was dramatically increased to the same magnitude as is typical for sintered LSGM pellets. The experimental results have demonstrated that the plasma-spraying process has a great potential for the integrated fabrication of medium-temperature SOFC units. The original version of this article was published as part of the ASM Proceedings, Thermal Spray 2003: Advancing the Science and Applying the Technology, International Thermal Spray Conference (Orlando, FL), May 5–8, 2003, Basil R. Marple and Christian Moreau, Ed., ASM International, 2003.  相似文献   
98.
Photographing impact of molten molybdenum particles in a plasma spray   总被引:1,自引:0,他引:1  
Plasma-sprayed molten molybdenum particles (∼40 μm in diameter) were photographed impinging at high velocity (∼140 m/s) on a glass substrate at room temperature. An optical sensor detected thermal radiation emitted by a droplet as it approached the substrate and activated a time delay unit. After a selected time interval, an Nd:YAG laser was triggered, emitting a 5 ns pulse that provided illumination for a charge-coupled device (CCD) camera to photograph the impacting droplet through a long-range microscope. By varying the delay before pulsing the laser, different stages of droplet deformation were recorded. Impacting droplets spread into a thin circular film that ruptured and broke into small fragments. An optical detector recording thermal radiation from the impacting droplet gave a signal that increased as the droplet spread out, reached a maximum when the liquid film began to rupture, and decreased as portions of the droplet recoiled because of surface tension and then flew out of view of the photodetector.  相似文献   
99.
离子氮化对镀铬层组织与性能的影响   总被引:2,自引:0,他引:2  
葛继平 《表面技术》1994,23(6):260-264
研究了镀铬层经离子氮化后的组织和性能。分别用SEM、电子探针和X光衍射仪观察和分析了复合处理层剖面的组织、结构和成分,试验结果表明:离子氮化能使镀铬层的网状裂纹弥合,可明显提高了镀层表面硬度、结合力和耐蚀性。  相似文献   
100.
压缩弧光等离子束熔覆层中晶相与非晶相   总被引:11,自引:1,他引:11  
用压缩弧光等离子束在 45钢表面熔覆Fe Cr Si B粉末涂层 ,采用能谱、透射电镜、电子探针对熔覆层结构进行分析。结果表明 ,熔覆层中晶相与非晶相并存 ,晶相由A(Me)、F(Me)、Me2 3 C6 等相组成 ,且 [2 11]A∥ [2 11]Me2 3 C6 ,(111) A ∥ (111) Me2 3 C6 ,(0 11) A ∥ (0 11) Me2 3 C6 ,即A与Me2 3 C6 保持共格关系 ,而[111]F∥ [32 1]Me2 3 C6 ,(10 1) F∥ (111) Me2 3 C6 。非晶相中Si、Cr等元素含量较高 ,从动力学和热力学两方面对非晶的形成进行了分析  相似文献   
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