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991.
LIANG YongFeng YE Feng LIN JunPin WANG YanLi ZHANG LaiQi & CHEN GuoLiang State Key Laboratory for Advanced Metals Materials University of Science Technology Beijing Beijing China 《中国科学:信息科学(英文版)》2010,(4)
Fe-6.5wt%Si alloy has excellent soft magnetic properties,but it is hard to be cold-rolled due to appearance of ordered phases in this alloy.In this paper we report that ultra thin Fe-6.5wt%Si sheet of 0.05 mm thick was obtained by heavily cold rolling.By means of optical microscope,micro-hardness indenter,instron,SEM and X-ray diffraction,the effect of heat treatment on mechanical properties of this alloy sheet was investigated.The heavily cold-rolled sheet exhibits some extent of ductility.The ultimate ten... 相似文献
992.
ZHANG JiaHua XU Yun YAO FengMei WANG PeiJuan GUO WenJuan LI Li & YANG LiMin Chinese Academy of Meteorological Sciences Beijing China Graduated University of Chinese Academy of Sciences Beijing USGS/EROS Data Center South Dakota USA 《中国科学:信息科学(英文版)》2010,(5)
Quantitative estimation of vegetation water content(VWC) using optical remote sensing techniques is helpful in forest fire as-sessment,agricultural drought monitoring and crop yield estimation.This paper reviews the research advances of VWC retrieval using spectral reflectance,spectral water index and radiative transfer model(RTM) methods.It also evaluates the reli-ability of VWC estimation using spectral water index from the observation data and the RTM.Focusing on two main definitions of VWC—the fuel mois... 相似文献
993.
XIN Ying GONG WeiZhi & ZHANG JingYin Innopower Superconductor Cable Co. Ltd. E.Rongchang Rd. Longsheng Industrial Park Beijing Economic & Technological Development Area Beijing China 《中国科学:信息科学(英文版)》2010,(4)
A superconductor has zero resistance at the superconducting state. This unique property creates many exceptional phenomena, of which some are known and the others are not. Our experiments with multilayer high temperature superconductor (HTS) cable samples revealed a new phenomenon that alternating current had a tendency to flow in the inner and outer layers of the cables. We attribute the cause of this phenomenon to the electromagnetic interaction in an infinite electrical conductivity medium and term it su... 相似文献
994.
LIU Jie LI JianLin QU JianJun ZHOU JiFang ZHANG ChaoFeng & LI JianWu Key Laboratory of Geological Hazards on Three Gorges Reservoir Area Ministry of Education China Three Gorges University Yichang China College of Civil Hydropower Engineering Er'tan Hydropower Development Company Ltd.Chengdu 《中国科学:信息科学(英文版)》2010,(5)
To reduce data variance caused by individual differences of different samples,a new experimental method is proposed by loading and unloading the axial forces with different frequencies and different waves of a certain load amplitude to the same rock sample without damaging it.Lag time segments are defined and fractionized into segments I and Ⅱ.Criterions for seg-mentation,definitions of relevant parameters and empirical analysis are also offered afterwards.In the course of sinusoidal loading,the serious pea... 相似文献
995.
LIU KaiHuang LIU TianCheng LI JianLiang ZHANG Liang ZHANG HongHao LI DeRen LU ZhiChao & ZHOU ShaoXiong China Iron Steel Research Institute Beijing China Advanced Technology Materials Co. Ltd. 《中国科学:信息科学(英文版)》2010,(4)
A composite consisting of flake-shaped Fe74Cr2Mo2Sn2P10Si4B4C2 particles was prepared.The flake-shaped particles included in the composite were prepared by planetary ball milling.The complex permeability of the composite material was measured at frequency range from 10 MHz to 8.5 GHz.The permeability of the composite containing flake-shaped particles was much higher than that of the spherical particles.The permeability of particles was improved by means of heat-treatment.In contrast to the random-spatial-di... 相似文献
996.
SHU XiaYun ZHANG HongHai LIU HuaYong XIE Dan & XIAO JunFeng School of Mechanical Science Engineering Huazhong University of Science Technology Wuhan China Division of MOEMS Wuhan National Laboratory of Optoelectronics 《中国科学:信息科学(英文版)》2010,(1)
Fluid dispensing is a method by which fluid materials(such as epoxy,adhesive,and encapsulant) are delivered in a controlled manner in electronics packaging.Fluid jetting,derived from inkjet technology,is a noncontact,data-driven fluid dispensing technology.But ideal fluid materials for packaging are usually high viscous,which is difficult to realize by traditional inkjet technology.In this paper,a mechanical micro-droplet jetting system for high viscosity fluid was proposed.It consists of dispensing valve,m... 相似文献
997.
An investigation was carried out by numerical simulation on a wind turbine airfoil and a blunt trailing-edge airfoil with and without vortex generators (VGs), and the performance of the airfoils was analyzed. By the simulation of airfoil DU 91-W2-250 it was verified that the numerical method and model were credible. Based on this airfoil, a new one with a blunt trailing edge of 6% chord was blended by symmetrically adding thickness, and its characteristics curves were obtained through computing at key angle... 相似文献
998.
本文阐述了刚性攻丝基本原理、硬件配置,梯形图编写,参数设置以及调试中的注意事项,FANUC数控系统在功能扩展和应用方面在生产中实际应用。 相似文献
999.
通过研究剪切模具对棒料剪切质量的影响因素,设计了一种适用于普通冲床的棒料精密剪切模具,该模具通过弹簧提供径向夹紧力,且径向夹紧机构与剪切刀具设在同一模具上.模具能够提高棒料剪切断面质量及下料效率,节约了生产成本. 相似文献
1000.
贯彻工序质量检验标准是产品质量稳定与提升的法宝 总被引:1,自引:0,他引:1
阐述了铸铁件生产的特点,各工序由于操作者的疏忽大意或者操作不当均可能使铸件产生缺陷。为防止这种缺陷的发生,必须制定工序质量检验标准;而贯彻执行这个标准不仅可以控制和杜绝缺陷的再发生,更是铸铁件类产品质量稳定与提升的法宝。 相似文献