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排序方式: 共有2043条查询结果,搜索用时 15 毫秒
11.
碘仿电解合成的工艺研究 总被引:3,自引:0,他引:3
开发了一种以石墨为阳极、铅为阴极、采用旋转阳极和离子膜分隔电解槽的碘仿电解合成的先进工艺 ,经过 5因素 4水平的正交试验 ,发现影响电流效率的各工艺因素中 ,阳极电流密度的影响最大 ,其次分别为阳极液温度 ,阳极液 p H值 ,阳极液中碘化钾的浓度和阳极转速。优化得到碘仿电合成的最佳工艺条件为 :碘化钾浓度 2 0 0 g· L- 1 ,阳极电流密度 2 5 A· dm- 2 ,阳极液温度为 2 0℃ ,阳极液 p H值为 9.5,阳极转速为2 0 0 r· min- 1 ,在此最佳工艺条件下 ,电流效率可达 97.2 3%。 相似文献
12.
Huyong Yan Guoyin Wang Di Wu Yu Huang Mingsheng Shang Jianjun Xu Kun Shan Xiaoyu Shi Jianhua Dong Lei Feng Botian Zhou Ye Yuan Yufei Zhao 《Water Resources Management》2017,31(5):1435-1456
In the field of water quality management, it is vital to determine the main precursory anomalies from the precursor of intricate water bloom in the context of a given area. In this paper, a water bloom precursor analysis method, based on two direction singular rough set, was proposed. This approach was produced on the basis of the different sections and pre-water bloom of water bloom precursor anomalies and characteristic of elements transferred in singular rough set. For testing the validity of two direction singular rough set application in water bloom precursor analysis, Xiangxi River, which is one of the typical tributaries of Three Gorges Reservoir in China, was selected as study area. The result showed that compared with other indexes, pH and dissolved oxygen (DO) are the most valuable indicators of water bloom in the precursory anomalies. Furthermore, regarding with water bloom precursory anomalies in Xiangxi River, most of the nutrient loading and biological community are the key indicators. Hence, this method can determine the main precursory anomaly for water bloom in the study area, which provides powerful knowledge support to water quality specialists for them to comprehensively analyze precursory anomaly so as to find out its relationship with occurrence law of water bloom. 相似文献
13.
14.
靳鸿 《武汉理工大学学报(材料科学英文版)》2010,25(4):588-591
The behavior of resistance high-g impact of EMC (epoxy molding compound) with two package models, small outline package (POS)
and Globtop, was evaluated by experimental method used Hopkinson bar. At 120,000 g (generated in the Hopkinson bar with widths
about 70 μ s) no damage in either the POS devices or the Globtop devices was observed. In order to enhance the EMC’s ability
of resistance high-g impact, buffering effect of epoxy resin was also studied. The experimental results above all show that
EMC has a better performance of impact resistance at about 120,000 g, and epoxy resin can absorb the stress wave to have the
protected ability. The study of this paper could serve as a basis for selection packaging materials and enhance its reliability
in high-g impact environment. 相似文献
15.
Huahai Shen Menglu Li Pengcheng Li Haiyan Xiao Haibin Zhang Xiaotao Zu 《Journal of the American Ceramic Society》2021,104(5):2301-2312
In the past decades, pyrochlores, such as Gd2Zr2O7, have demonstrated great potential to immobilize nuclear wastes such as Pu, which results in the production of Pu2Zr2O7. Due to the high radioactivity of Pu, it is difficult to investigate the radiation response behavior of Pu2Zr2O7 and its physical properties of the damaged state experimentally. Consequently, few related data have been reported in the literature thus far. In this study, first-principles calculations have been carried out to investigate the defect formation and its effect on the thermodynamic properties of Pu2Zr2O7. It reveals that PuZr antisite and O8a interstitial defects are very easy to form in Pu2Zr2O7. In particular, the O8a interstitial defect can be formed spontaneously, while it is mechanically unstable. When vacancy, interstitial or antisite defects are formed in Pu2Zr2O7, and the elastic moduli and Debye temperature are decreased. Besides, better ductility is resulted. As compared with other zirconate pyrochlores, such as Gd2Zr2O7, the Pu2Zr2O7 is suggested to be less resistant to radiation-induced amorphization. This study demonstrates that the created defects due to self-radiation from actinide decay have remarkable influences on the thermophysical properties of Pu2Zr2O7. 相似文献
16.
研究了BNi-2钎焊条真空吸铸原理,并由试验得出:当BNi-2合金加热到1500℃,真空控制阀门开口为φ6mm以上,真空度50kPa,铸型预热温度500℃,并用φ内2mm×500mm石英管进行真空吸铸时,吸铸高度可达到40cm以上。 相似文献
17.
ZHANG Xiuying LOU Xiangdong YIN Guoyin and ZHANG Youjua
) College of Chemistry Environmental Science Key Laboratory of Environmental Science Engineering Education Commission of Henan Henan Normal University Xinxiang China
) Anyang teachers college Anyang China 《稀有金属(英文版)》2004,(1)
The extraction behavior and mechanism of gallium(Ⅲ) and thallium(Ⅰ) or indium(Ⅲ) and thallium(Ⅰ) with Sec-octylphenoxy acetic acid (CA-12) from hydrochloric acid solution in sulphonating kerosene were studied. Optimum extraction conditions were evaluated from critical study of various experimental parameters and the probable composition of the extracted species is ascertained from lg D-lg C plots. The effects of different ions on the determination of these ions were examined. 相似文献
18.
电化学扫描探针显微镜在腐蚀电化学研究中的应用 总被引:4,自引:0,他引:4
从电化学扫描探针显微镜(ECSPM)的工作原理出发,综述了近几年电化学扫描探针显微镜在腐蚀电化学领域的研究进展,指出电化学扫描探针显微镜在原位,局部腐蚀,腐蚀早期过程等电化学中有重要的应用价值。 相似文献
19.
基于CMS的企业网站的设计与实现 总被引:12,自引:2,他引:10
为了使企业网站能及时更新,具有个性和便于维护管理,提出了使用内容管理系统(CMS)来构建一个基于内容管理的企业级网站的解决方案.介绍了有关内容管理的技术背景和相关理论,论述了运用内容管理的理论和相关技术,采用J2EE技术构建一个基于内容管理的企业级网站系统架构的过程.详细介绍了该网站的主要设计目标以及围绕该目标的具体设计思路,重点介绍了权限管理、文件的上传与下载、新闻管理这3大关键技术模块的设计与实现. 相似文献
20.
As service robots and other ubiquitous technology have evolved, an increasing need for the autonomous navigation of mobile
objects has arisen. In a large number of localization schemes, the absolute-position estimation method, which relies on navigation
beacons or landmarks, has been widely used as it has the advantages of being economical and accurate. However, only a few
of these schemes have expanded their application to complicated workspaces, or those that have many rooms or blocks. As the
navigation of mobile objects in complicated workspaces is vital for ubiquitous technology, multiblock navigation is necessary.
This article presents methodologies and techniques for the multiblock navigation of the indoor localization system with active
beacon sensors. This new indoor localization system design includes ultrasonic attenuation compensation, dilution-of-precision
analysis, and a fault detection and isolation algorithm using redundant measurements.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献