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991.
Shanshan Wang Baicong Wei Mei Li Wei Han Milin Zhang Xiaoguang Yang Yang Sun 《中国稀土学报(英文版)》2018,36(9):1007-1014
An electrochemical study of dysprosium (III) on Bi film electrode was carried out in eutectic LiCl-KCl melts by transient and steady state electrochemical techniques. The results of transient electrochemical techniques showed that the reduction of Dy (III) appears at a more positive value than the one detected on W electrode owing to the formation of Bi-Dy intermetallic compounds through electrochemical deposition of Dy on bismuth film electrode. The thermodynamic properties of the formation for Dy-Bi intermetallics were estimated by a steady state electrochemical method in a temperature range of 713–803 K. Furthermore, the electrochemical preparation of Bi-Dy alloys was conducted by galvanostatic electrolysis at different current intensities. The Bi-Dy alloys, characterized by scanning electron microscopy equipped with energy dispersive spectrometry and X-ray diffraction, are comprised of DyBi3/5 and DyBi phases. 相似文献
992.
M. Venkataravanappa R.B. Basavaraj G.P. Darshan B. Daruka Prasad S.C. Sharma P. Hema Prabha S. Ramani H. Nagabhushana 《中国稀土学报(英文版)》2018,36(7):690-702
Latent fingerprints (LFPs) are the major physical evidences for the identification of individuals during crime spot investigation. Till date, numerous methods were followed to visualize LFPs. However, simple, accurate, and cost-effective method has wide scope in advanced forensic field. In our work, Ca2SiO4:Dy3+ nanopowders (NPs) were fabricated via solution combustion route. The optimized sample was employed for the visualization of overlapped LFPs by the cost effective powder dusting method. The obtained results reveals the complete three levels of ridge characteristics with high sensitivity, reproducibility, selectivity, and reliability on various complex surfaces. The photoluminescence (PL) spectra consist of intense peaks at ~ 480 and 574 nm owing to 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 4f transitions of Dy3+ ions, respectively. The photometric properties confirm that the samples exhibit intense white emission with high color purity. Therefore, the prepared NPs could be a definitive choice as an advanced luminescent NPs for forensic, solid state lighting and portable FED devices. 相似文献
993.
包头稀土选矿技术进展 总被引:3,自引:2,他引:1
论述了包头白云鄂博矿稀土选矿技术发展的历程,阐述了该矿稀土选矿的现状及技术指标,分析了各发展阶段浮选药剂的特性及工艺流程的特点。 相似文献
994.
基于工业控制网络的系统集成 总被引:1,自引:0,他引:1
本文系统地论述了工业控制网络的系统集成方式,并对各种构成形式和特点进行了讨论,给出了具体的系统集成结构。通过造纸厂板纸机控制系统集成实例,表明了系统集成在生产制造领域中的重要作用。 相似文献
995.
Chuck Eastman 《Architectural Design》2009,79(2):52-57
Building information modelling (BIM) is a powerful tool for clients and architects alike, particularly when clients have ongoing complex programmatic requirements. Chuck Eastman describes how with his team* at the AEC Integration Laboratory at the College of Architecture at the Georgia Institute of Technology he was commissioned by the US federal government's General Service Administration (GSA) to automate the design guidelines for all US courthouses in such a way that preliminary designs by architects could be assessed and checked against specific criteria. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
996.
Earth reinforcement using soilbags 总被引:1,自引:0,他引:1
This paper describes the method of earth reinforcement using soilbags and illustrates its application for case studies involving a pond and the expansive soil slope protection for a highway. The strength properties of soilbags were investigated using unconfined compression tests and bearing capacity tests on real soilbags containing either medium grained sands or gravels. The test results show that soilbags have high strength when subjected to an external load. This is primarily attributed to the mobilization of tensile forces in the bags. It is concluded that earth reinforcement using soilbags could substantially improve the bearing capacity of soft ground as well as minimizing deformation under working loads. 相似文献
997.
《电气》2008,19(1)
The 16th National Congress of the Communist Party of China was held inNovember 2002. In the five years since then, great changes took place in Chinesepower industry. Power institutional reform was deepened; the construction ofboth power sources and power grids was speeded up; the tense situation of powersupply and demand was alleviated; the safety and reliability of power productionwere improved; the management on power tariff was standardized; environmentalprotection and energy conservation achieved good r... 相似文献
998.
以“溶胶喷雾干燥-纳米原位复合”合成的超细/纳米W-0.3%Y复合粉末为原料,通过普通模压-预烧和在1800~1950℃下烧结制备细晶钨合金。检测了合金显微硬度和拉伸强度,并利用扫描电镜SEM和X射线能量色散谱(EDX)观察了断口形貌及显微组织,研究其烧结行为及断裂行为变化。结果表明:微量稀土Y以Y2O3二次相粒子的形式均匀弥散分布于W晶粒的晶内和晶界处,能有效抑制W晶粒的长大,显著细化晶粒,提高其力学性能。微量稀土Y的添加改变了W合金的断裂形式,由纯W的沿晶断裂转变为主要沿晶、部分穿晶的断裂方式。 相似文献
999.
文章对保护接地和保护接零进行了分析对比,介绍了不同低压供电系统对保护接地和保护接零的要求,指出选用不正确造成的危害。 相似文献
1000.
具有行业特色高校的研究生规模一般不大,但是却承担着培养行业精英的重任,许多行业的中高层领导和技术骨干均来自于这些高校,在新的社会和高校大发展的形势下,行业特色高校必须与时俱进,按照国家和行业发展的需要,加大创新力度,不断探析构建适合本校和本行业研究生培养的党建模式。 相似文献