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991.
In this research, polyester fabrics were treated with three concentrations (10, 20 and 30 g/L) of macro- and microemulsions of silicones in water at 30 °C by the padding method. The treated fabrics were then dried/cured at 130 °C for 40 s. Some of the physical and chemical properties of the samples are discussed. The drapeability of treated samples was lower and found to depend on the silicone particle size. Moisture absorbency of treated samples was also lower. Colorimetric properties of softener treated fabrics were evaluated with a reflectance spectrophotometer. Scanning electron microscope (SEM) examinations showed an aggregation of silicone particles on the fiber surface.
Mazeyar ParvinzadehEmail:
  相似文献   
992.
To commemorate the awarding of the Nobel Prize for Chemistry to Daniel Shechtman for his discovery of quasicrystals, this paper reviews our recent studies of the interaction of rare gases and hydrocarbon gases with the tenfold surface of quasicrystalline decagonal Al-Co-Ni.  相似文献   
993.
连铸连轧非调质钢的强度计算及其预报   总被引:7,自引:0,他引:7  
刘志林  刘伟东  林成 《金属学报》2004,40(12):1248-1252
非调质钢的强度为α-Fe基体细化强度与固溶强化、奥氏体析出碳化物弥散强化、界面强化和过饱和铁素体析出碳化物的析出强化的强度增量之和.以细晶铁素体强度为基础,利用相最强键上的共用电子数nA及相界面电子密度差△p计算了连铸连轧非调质钢固溶强化、界面强化、弥散强化和析出强化的强度增量.给出了一组计算非调质钢连铸连轧终轧强度的公式.可根据化学成分和工艺规定的终轧晶粒尺寸计算终轧强度,或根据技术要求的强度给出相应的轧制晶粒尺寸与化学成分间的最佳组合.实现了化学成分——轧制晶粒尺寸——终轧强度的计算机预报.  相似文献   
994.
Polymer films consisting of nematic liquid crystal (LC) droplets and polymer networks were prepared by using a low-energy electron beam to irradiate a homogeneous mixture of nematic LC and bifunctional methacrylate monomer. Influences of such polymerization conditions as polymerization temperature, monomer concentration, and radiation energy on electrooptical properties of the compound films were examined. The polymer yield, affecting to a large extent the film properties, depended on the monomer concentration and the radiation energy. Compound films, which have a switching function from the scattering state to transparency by applying approximately 20–30 V between the two sides of the film, were obtained. In addition, it was found that a compound film with excellent electrooptical properties was prepared by changing impure LC in the droplets into pure LC. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1675–1681, 1997  相似文献   
995.
We have synthesized double wall carbon nanotubes (DWNTs) with few defects and little amorphous carbon by hot wall chemical vapor deposition (CVD) of alcohol. Catalysts for the DWNT growth were made from cobalt and molybdenum acetates. Scanning electron microscopy, transmission electron microscopy, multi frequency resonance Raman spectroscopy and optical absorption spectroscopy were used for characterization of the product with regard to DWNT yield, the nanotube diameter distribution, defect concentration and amorphous carbon content. Base pressures lower than 1 × 10−5 mbar in the CVD reactor considerably suppress defects in the DWNTs. Optimized growth conditions for DWNT formation are presented.  相似文献   
996.
Carbon dioxide and carbon monoxide undergo reactive chemisorption with cesium modified Cu(110) and Cu(110)-O surfaces and via the anionic intermediate CO 2 (a) form a surface carbonate. The CO 2 (a) species was characterised by VEELS and XPS at low temperature (80 K) and the surface carbonate at 295 K. For cesium modified Cu(110) surfaces chemisorption of carbon monoxide gives rise to electron energy loss peaks (v co) as low as 1450 cm–1 at 295 K.  相似文献   
997.
形成高压纳秒脉冲仿真线的设计   总被引:1,自引:0,他引:1  
本文叙述了高低阻抗线和螺旋带传输线的设计原则,并利用这二种仿真线在同轴50Ω负载上获得了快前沿的高压纳秒脉冲。实测结果表明,脉冲的上升时间小于0.4ns,宽度从1.65~10.6ns可变,幅值大于2000V。  相似文献   
998.
A nanocrystalline alloy with a nominal composition of Ni20Fe20Cr20Co20Zn15Mn5 was produced by mechanical alloying and processed using annealing treatments between 450 and 600 °C for lengths from 0.5 to 4 h. Analysis was conducted using x-ray diffraction, transmission electron microscopy, magnetometry, and first-principles calculations. Despite designing the alloy using empirical high-entropy alloy guidelines, it was found to precipitate numerous phases after annealing. These precipitates included a magnetic phase, α-FeCo, which, after the optimal heat treatment conditions of 1 h at 500 °C, resulted in an alloy with reasonably good hard magnetic properties. The effect of annealing temperature and time on the microstructure and magnetic properties are discussed, as well as the likely mechanisms that cause the microstructure development.  相似文献   
999.
基于现代电力电子技术的先进动态制动,是提高电力系统输电暂态稳定性的最直接、有效的方法之一。本文从相平面分析方法出发,推导出一种先进动态制动的控制策略。计算机仿真的结果表明,先进的动态制动能显著地提高暂态稳定,还能阻尼输电系统的振荡。  相似文献   
1000.
Graphene has the advantages of high electrical conductivity, high heat conductivity, and low noise, which makes it a potential option for integrated circuits interconnection and nanoelectrodes. In this paper, we present a novel fabrication method for graphene nanoeletrodes with nanogap. First, graphene grown by chemical vapor deposition (CVD) is assembled to a chip with microelectrodes. Second, an atomic force microscopy (AFM) based mechanical cutting method is developed to cut the graphene into nanoribbons and nanoeletrodes with nanogap. Then the electronic property of a single nanodot is characterized using the garphene nanoelectrodes, demonstrating the effectiveness of the graphene nanoelectrodes. The fabricated graphene nanoeletrode pairs can be used as probes to detect single molecule in micro-environment, and show an attractive prospect for future molecular electronics applications.  相似文献   
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