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31.
The effect of annealing on microstructure,adhesive and frictional properties of GeSb 2 Te 4 films were experimentally studied.The GeSb 2 Te 4 films were prepared by radio frequency(RF)magnetron sputtering,and annealed at 200℃and 340℃under vacuum circumstance,respectively.The adhesion and friction experiments were mainly conducted with a lateral force microscope(LFM)for the GeSb 2 Te 4 thin films before and after annealing.Their morphology and phase structure were analyzed by using atomic force microscopy(AFM)and X-ray Diffraction(XRD)techniques,and the nanoindention was employed to evaluate their hardness values.Moreover,an electric force microscope(EFM)was used to measure the surface potential. It is found that the deposited GeSb 2 Te 4 thin film undergoes an amorphous-to-fcc and fcc-to-hex structure transition;the adhesion has a weaker dependence on the surface roughness,but a certain correlation with the surface potential of GeSb 2 Te 4 thin films.And the friction behavior of GeSb 2 Te 4 thin films follows their adhesion behavior under a lower applied load.However,such a relation is replaced by the mechanical behavior when the load is relatively higher.Moreover,the GeSb 2 Te 4 thin film annealed at 340℃presents a lubricative property. 相似文献
32.
以硫酸、磷钨酸、ZRP-5分子筛为催化剂,研究了二甘醇(DEG)脱水环化的反应规律。结果表明,DEG发生分子内脱水环化反应,生成1,4-二氧六环(DOX),DEG分子间脱水不仅可以生成四甘醇、六甘醇等,同时可生成三甘醇、五甘醇等一系列的多甘醇(PEG)。不仅DEG可以脱水环化生成DOX,在反应中生成的PEG也同样可以进行生成DOX的反应。对于二甘醇(DEG)脱水环化反应,硫酸是性能优良的催化剂,反应可以在较低的温度下进行,馏出产物中DOX选择性大于95%。 相似文献
33.
34.
从水淬渣中回收镓的试验研究 总被引:5,自引:0,他引:5
对鼓风炉(ISP法)或烟化炉水淬渣中回收镓的工艺进行了研究。结果表明,利用浓硫酸恒温熟化的独特浸出工艺,克服硅对液固分离的影响;以伯胺N9123作为萃取剂在硫酸介质中萃取镓;获得了含镓品位为2.82%的富集物。 相似文献
35.
合成2,4-二叔丁基苯酚工业试验 总被引:2,自引:0,他引:2
以离子交换树脂为催化剂,苯酚和甲基叔丁基醚为原料合成2,4-二叔丁基苯酚(简称2,4酚),合成产物经过滤再经间歇真空精馏精制提纯,得到高纯度的2,4酚成品。成品精馏后釜中残液在酸性白土催化剂的作用下通过歧化反应生成对叔丁基苯酚,再经精馏提纯得到成品对叔丁基苯酚。通过工艺优化,使2,4酚、对叔丁基苯酚形成联产生产工艺,降低了生产原料消耗和成本。 相似文献
36.
介绍了视频压缩技术从MPEG1、MPEG2到目前主流技术MPEG4,分析了数字视频存储、检索、传输上优于模拟技术的特点,从而使视频网络应用,数据库支撑的应用、安防行业的数字化应用的迅速发展。 相似文献
37.
介绍了在Window系统中设计兼容IPv4及IPv6的网络程序的方法,并给出了用WinsockAPI编程的具体步骤。 相似文献
38.
Influence of Ni Interlayers on the Mechanical Properties of Ti6Al4V/(WC-Co) Friction Welds 总被引:2,自引:0,他引:2
M. Shamanian M. Salehi A. Saatchi T. H. North 《Materials and Manufacturing Processes》2003,18(4):581-598
Ni interlayers were introduced prior to dissimilar friction welding of Ti6Al4V base material to three cemented carbide substrates. The fracture strength of Ti6Al4V/(WC-6 wt% Co) welds were poor and were markedly improved when 20-µm thick Ni interlayers were introduced prior to dissimilar friction welding. These results were only produced when the (WC-6 wt% Co) cermet was electroplated prior to friction welding. When the Ti6Al4V alloy was electroplated prior to friction welding, fractured WC particles and cracking were observed in the (WC-Co) carbide substrate. The fracture strengths of Ti6Al4V/(WC-11 wt% Co) and Ti6Al4V/(WC-24 wt% Co) welds were not improved when 20-µm thick Ni interlayers were introduced prior to friction welding. During mechanical testing, the Ni layer retained at the dissimilar joint interface created a region of weakness. 相似文献
39.
F.A. Rodrigues 《Cement and Concrete Research》2003,33(6):823-827
This paper describes the synthesis of cements, chemically and structurally related to Ca2SiO4. Silica was obtained from rice hull after heating at 600 °C. Calcium oxide and small amounts of barium chloride were mixed in order to obtain a final (Ca/Si) or (Ca+Ba)/Si ratio equal to 1.95, 1.90, and 1.80, which is lower than in the conventional cement. The solids were mixed and ultrasonically treated for 1 h with a water/solid ratio of about 20. After drying and grinding, the mixtures were heated up to 1100 °C. It was possible, in some cases, to obtain a cementitious material. These cements are structurally related to β-Ca2SiO4 and the lower (Ca+Ba)/Si ratio obtained was 1.95. The initial chemical compositions of these cements are: (Ca1.83+Ba0.12)SiO4 and (Ca1.79+Ba0.16)SiO4. A further lowering in the (Ca+Ba)/Si ratio changes the nature of the silicates. 相似文献
40.
介绍了针对早期建筑的混凝土桥梁碳化情况采用H52-S4环氧厚浆涂料进行封闭保护、防腐处理的施工方法及施工工艺,并提出施工中应注意的有关事项,对温度影响、表面气泡处理进行了讨论,提出合理化建议。 相似文献