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41.
LUO Jun QI LeHua * ZHOU JiMing XIAO Yuan & YANG Fang School of Mechatronics Northwestern Polytechnical University Xi’an China Key Laboratory of Contemporary Design Integrated Manufacturing Technology Ministry of Education 《中国科学:信息科学(英文版)》2011,(7)
Electrostatic delivery of charged uniform metal droplets is a novel method to deposit metal parts with short process period and low cost. But the delivery process is unstable and delivery accuracy of charged droplets deteriorates because of actions of mutual interactions of closely charged droplets. A droplet generator with droplet charging and deflecting system has been established to find out the way for stably and accurately deflecting droplets. The parameters for generating uniform droplets were first s... 相似文献
42.
ZHAN Mei JIANG ZhiQiang YANG He XU XuDong & LI GuangJun State Key Laboratory of Solidification Processing College of Materials Science Engineering Northwestern Polytechnical University P.O.Box Xi’an China Chengdu Aircraft Industry Corporation Ltd Chengdu 《中国科学:信息科学(英文版)》2011,(4)
The rapid development of aviation and aerospace technologies has led to increased interest in the application of numerically controlled(NC) technology for bending light-weight titanium alloy tubes.In order to study and develop advanced NC bending technology,it is necessary to understand the bending performance of medium strength TA18(Ti-3Al-2.5V,ASTM Gr.9) titanium alloy tubes during NC bending under different die sets.This paper focuses on the bending performance of medium strength TA18 tubes under differe... 相似文献
43.
TANG HuiPing ZHU JiLei XI ZhengPing DI XiaoBo WANG JianYong & AO QingBo State Key Laboratory of Porous Metal Materials Northwest Institute for Nonferrous Metal Research Xi’an China 《中国科学:信息科学(英文版)》2010,(2)
Characterization of pore structure is one of the key problems for fabrication and application research on porous materials. But, complexity of pore structure makes it difficult to characterize pore structure by Euclidean geometry and traditional experimental methods. Fractal theory has been proved effective to characterize the complex pore structure. The box dimension method based on fractal theory was applied to characterizing the pore structure of fiber porous materials by analyzing the electronic scannin... 相似文献
44.
N—邻甲苯基—N‘—(对氨基苯磺酸钠)硫脲的合成及与钯(Ⅱ)显色反应的研 … 总被引:1,自引:1,他引:0
45.
46.
ZHU Jie OUYANG XiaoPing &CHEN Da Northwest Institute of Nuclear Technology Xi’an China College of Material Science Technology Nanjing University of Aeronautics Astronautics Nanjing 《中国科学:信息科学(英文版)》2011,(9)
The aim of this study was to evaluate the influence of different entrance surface treatments of the scintillator on the intrinsic spatial resolution of a scintillation camera.The primary scintillation light reflection on the entrance surface of a scintillator may be affected by the optical coating of the entrance surface,resulting in either spatial resolution or system detection efficiency degradation.A Monte Carlo simulation model,based on Geant4 codes,was developed in order to study the scintillation ligh... 相似文献
47.
GUO Ting-ting LI Shao-hua Department of Energy mechanical Engineering Northeast Dianli University Jilin China XU Zhong School of Energy Power Engineering Xi’an Jiaotong University Xi’an China 《水动力学研究与进展(B辑)》2006,18(3):319-323
1. INTRODUCTION The interaction of jets with crossflow generates complex flow fields which exist in a variety of industrial applications, e.g. internal film cooling of turbine blades, dilution air jets in combustion chambers, jet from V/STOL aircraft in transition flight. Systematic experimental, theoretical and numerical investigations of the flow fields began several decades ago, where the parameters studied include the jet injection angel, the jet-to-crossflow velocity ratio, the jet … 相似文献
48.
Wei Wen-li 《水动力学研究与进展(B辑)》2002,14(1)
1. INTRODUCTIONOpen channels carrying supercritical flows are commonly used in hydraulic engineering. Man-made structures such as spillway chutes, conveyance channels, sewer systems, and outlet works are some typical examples. Similarly, supercritical flo… 相似文献
49.
<正> 忘掉那些华而不实的新特性吧!图形专家们真正需要的是省时、功能完善的插图程序,而图形软件公司终于做到了这一点。CorelDraw 7通过简化和改进完善其已有特性在这方面迈出了第一步。现在,Abode Illustrator 7.0也采用类似的方针,而且在跨平台功能方面还进行了改进。最终结果是该产品成为一个强有力的绘图工具包,它外观更清爽、运行速度更快而且为用户提供了用于创建能够想像到的任意图形的所有工具。 从Mac系统开始 尽管Illustrator 4.1 for Windows曾经是一个相当不错的图形生成工具,但它还是落后于其相应的全功能Mac版本。Illustrator 7.0 相似文献
50.
A solenoid-type inductor for high frequency application is realized using a micro-electro-mechanical systems (MEMS) technique.In order to achieve a high inductance value and Q factor,UV-LIGA,dry etching technique,fine polishing and electroplating technique are adopted.The dimensions of the inductor are 1500μm×900μm×70μm,having 41 turns with a coil width of 20μm separated by 20μm spaces and a high aspect ratio of 3.5∶1.The maximum measured inductance of the inductor is 6.17nH with a Q factor of about 6. 相似文献