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951.
Wu Wengang Li Yi Huang Fengyi Han Xiang Zhang Shaoyong Li Zhihong Hao Yilong 《半导体学报》2006,27(4):662-666
报道了一种由悬浮在玻璃衬底上的表面镀铜平面单晶硅螺线构成的新型MEMS电感,可消除衬底损耗及减小电阻损耗.采用一种硅玻璃键合-深刻蚀成型释放工艺并结合无电镀技术制作该电感,形成厚约40μm的硅螺线,在硅螺线表面镀有高保形厚铜镀层,在铜镀层表面镀有起钝化保护作用的薄镍镀层.该电感的自谐振频率超过15GHz,在11.3GHz下,品质因子达到约40,电感值超过5nH.基于该电感的简化等效电路模型,采用一种特征函数法进行了参数提取,模拟结果与测量结果符合得很好. 相似文献
952.
Ronghui Lin Liang Fang Xinping Li Yingxin Xi Sufeng Zhang 《Polymer International》2006,55(11):1249-1253
Phenol–formaldehyde (PF) resins modified with nanosized copper particles were synthesized by an in situ polymerization process. X‐ray diffraction analysis and transmission electron microscopy revealed that the copper particles in the resulting PF resins had a spherical geometry with a size of 30–60 nm in diameter, and there were about 5% of the particles which were agglomerated. The thermal properties of the resulting PF resins were investigated using TGA. It was found that the copper nanoparticles markedly improved the thermal stability of the PF resins at lower temperatures. The initial decomposition temperature of the modified PF resins could be increased by 47 °C compared to unmodified resins. However, the copper nanoparticles increased the rate of degradation of the PF resins at elevated temperatures. The effects of copper nanoparticles on the thermal properties of the PF resins when used as binders for friction materials are beneficial. The toughness of the resulting PF resins was also studied. The results revealed that copper nanoparticles obviously improved the brittleness of the PF resins. The impact strength of the modified PF resins was increased by 66.6% compared to unmodified resins. Copyright © 2006 Society of Chemical Industry 相似文献
953.
954.
A new method is proposed to prospect copper deposits with portable XRF analyzer. The method is based on the close relation between Cu and the chalcophile elements or some other elements in the geochemical anomalies of a Cu deposit. Applications of the technique in Northeast China are presented. 相似文献
955.
Anastasios I Zouboulis Nick K Lazaridis Kostas A Matis 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2002,77(8):958-964
Biosorptive flotation was used as a combined operation for the simultaneous abstraction of nickel, copper and zinc ions from aqueous streams. Laboratory‐scale batch experiments, as well as pilot‐scale continuous experiments, have been conducted. Grape stalks, a by‐product of the winery industry, were used as sorbent material. The experimental procedure consisted of two consecutive stages: (i) biosorption, and (ii) flotation. The possibility of reusing biomass, after appropriate elution, was also examined. The main parameters examined were biomass concentration, particle size of sorbent, surfactant concentration, pH and flocculation. Flotation removals, following laboratory‐scale experiments, were found to be in the order of 100, 85 and 70% for copper, zinc and nickel, respectively. In pilot‐scale experiments, biomass sorption capacities were determined as 25 for copper, 81 for zinc and 7 µmol dm?3 for nickel. The order of biomass affinity regarding the studied metals was Cu > Zn > Ni. Short retention time and high effectiveness suggest that biosorptive flotation is a promising treatment process for the removal of toxic metals from contaminated aqueous solutions. © 2002 Society of Chemical Industry 相似文献
956.
本文对山东省冶金行为“八五”期间连铸建设和生产情况进行总结分析,提出了下一步连铸应向全连铸全精炼送,全一火成材近终形连铸方向发展。 相似文献
957.
纯铝中硅铁铜镓钛的光度法快速测定 总被引:1,自引:0,他引:1
提出了用一份制备液同是测定纯铝中硅,铁,铜,镓钛的新方法。用氧化钠溶解试样,盐酸酸化,然后用硅钼蓝光度法测定硅,邻二氮杂菲光度法测定铁,双环己酮草酰二腙光度法测定铜,丁基罗丹明B光度法测定镓,二安替比啉甲烷光度法测定钛,利用该方法分析铝标样,其结果与标准值合合,该方法简便,快速,准确。 相似文献
958.
阐述了多台变压器力率不均衡将引起附加铜损,推导出各变压器力率不均衡附加铜损的计算公式,提出了按均衡力率分配无功补偿容量的计算方法,为均衡力率节约电能提供了理论基础。 相似文献
959.
The behavior of dissolved Fe, Mn, Cu and Cd in the Duwamish River downstream of a sewage treatment plant located near Seattle, Washington, was investigated in three distinct zones: (1) immediately downstream of the effluent outfall, (2) further downstream in the freshwater portion of the river and (3) in the estuarine mixing zone. A three-end-member tracer model utilizing salinity and dissolved inorganic nitrogen was developed to distinguish physical mixing processes from biogeochemical reactions. The results of this investigation indicate that Fe was removed from the dissolved phase onto particulates near the plant. Although no additional reactions controlled the distribution of dissolved Fe, Mn and Cu in the freshwater portion of the river, Cd was removed from the dissolved phase. In the estuarine mixing zone, a significant fraction of the dissolved Fe and Cu was removed from solution, while Mn and Cd desorbed from particulates. The chemical forms of the trace metals rather than their sources appear to determine their participation in these reactions. 相似文献
960.