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71.
MI Jing LIU XiaoPeng LI ZhiNian JIANG LiJun HUANG Zhuo & WANG ShuMao Energy Material Technology Research Institute General Research Institute for Non-ferrous Metals Beijing China 《中国科学:技术科学》2010,(4)
In this paper,the effects of Si and Ce on the microstructure and hydrogen storage property of Ti26.5 Cr20V45Fe8.5Ce0.5 alloy were studied,respectively.First of all,effects of Si on the microstructure and hydrogen storage properties of Ti26.5Cr20(V45Fe8.5)1-xSixCe0.5(x=0,0.5,1.0,1.5 and 2.0 at%)alloys were studied by X-ray diffraction,scanning electron microscopy and P-C isotherm measurements.As the Si addition increases,the hydrogen absorption capacities of alloys decrease but the equilibrium pressure incre... 相似文献
72.
HE XinBo QU XuanHui REN ShuBin & JIA ChengChang School of Materials Science Engineering State Key Laboratory for Advanced Metals&Materials University of Science Technology Beijing Beijing China 《中国科学:技术科学》2010,(4)
The continuing miniaturization of electronic devices in microelectronics and semiconductors drives the development of new packaging materials with enhanced thermal conductivity to dissipate the heat generated in electronic packages.In recent years,several promising composite materials with high thermal conductivity have been developed successfully for high performance electronic equipment to replace the traditional Kovar and Cu/W or Cu/Mo alloys,such as SiCp/Al,SICp/Cu,diamond/Al and diamond/Cu.However,thes... 相似文献
73.
XIN RenLong WANG BingShu CHEN XingPin HUANG GuangJie & LIU Qing College of Material Science Engineering Chongqing University Chongqing China National Engineering Research Center for Magnesium Alloys 《中国科学:技术科学》2010,(4)
This study aimed to investigate dynamic recrystallization(DRX)behavior during compression of magnesium alloy AZ31. Cylinder samples were cut from the extruded rod and hot rolled sheet AZ31 for compression test.The samples were compressed using a Gleeble 1500D at a temperature of 300℃and a strain rate of 0.01 s-1.Grain orientations and misorientation angles across grain boundaries for the tested samples were obtained by using electron backscatter diffraction(EBSD)technique.The results showed that strong basal texture was observed after 50%compression(ε=0.69)on both the extruded and hot rolled samples,which have different initial textures.It was observed that with increased strain,DRX grains gradually rotated to basal orientation,and grain boundaries with misorientation angle of near 30°was formed in the samples.At the strain of 0.69,a high fraction of high-angle(60°)boundaries was present in the extruded sample,whereas almost no high angle boundaries were observed in the hot rolled sheet sample. 相似文献
74.
CAO DengQing WANG LiGang CHEN YuShu & HUANG WenHu School of Astronautics Harbin Institute of Technology Harbin China 《中国科学:技术科学》2010,(3)
To study the nonlinear dynamic behavior of the bladed overhang rotor system with squeeze film damper (SFD),a blade-overhang rotor-SFD model is formulated using the lumped mass method and the Lagrange approach.The cavitated short bearing model is employed to describe the nonlinear oil force of the SFD.To reduce the scale of the nonlinear coupling system,a set of orthogonal transformations is employed to decouple the one nodal diameter equations of blades,which are coupled with the dynamical equations of the ... 相似文献
75.
This study examined the individual and simultaneous adsorption of SOx(SO2)and NOx(NO-NO2)on activated carbon prepared from waste palm shell.The adsorption process was examined in a fixed bed reactor at low temperatures(100 300°C).For individual adsorption without any catalytic activation,SOx showed good adsorption whereas NOx was very much poor.In the simultaneous adsorption of SOx and NOx,SOx showed greater adsorption affinity than NOx.For palm shell activated carbon(PSAC)impregnated with metal catalyst(Ni and Ce)the concentration adsorbed profile showed that the amount of SOx adsorbed decreased regularly,while the amount of the adsorbed NOx increased irregularly.The properties of the pure and impregnated PSAC were analyzed by BET,SEM and EDX.These investigations indicated that PSAC impregnated with metal catalyst is the determining factor in the adsorption of SOx and NOx simultaneously. 相似文献
76.
Hu Jinlian.Shi FengjunThe Hong Kong Polytechnic University Hung Hom Kowloon Hong KongYu TongxiThe Hong Kong University of Science & Technology Cleat Water Bay Kowloon Hong Kong. 《东华大学学报(英文版)》1999,(2)
Under the assumption of semi - circular form for a fabric bend, creasing of fabric strips and compression of fabric loops are analyzed by neglecting the structural complexity of the fabric. The relationship between the creasing force and deformation are deduced using an energy method and solutions are given for a linearly elastic material with constant internal frictional constraint. The agreements between the theoretical predictions and experimental results are very satisfactory. 相似文献
77.
教育产业化若干问题的思考 总被引:2,自引:0,他引:2
教育产业化的理论和实践探讨在我国刚刚兴起 ,所以对教育产业化的界定还没有统一的定论。基于此 ,本文提出了教育产业化应是教育全过程产业化的观点 ,同时 ,探讨了教育产业化的根本原因、基本特征、客观必然性、基本条件和可操作性策略 相似文献
78.
宁夏南部黄土高原地区土地适宜性评价研究 总被引:6,自引:0,他引:6
根据联合国粮农组织(FAO)土地评价纲要的分类体系,采用定性与定量相结合的方法,对宁夏南部黄土高原地区的土地进行了适宜性评价,并给出了该地区的土地适宜性能、质量等级、数量分布及亚级的数量和分布特征. 相似文献
79.
于秀媛 《辽宁大学学报(自然科学版)》1999,26(4):299-301
由消费、投资、进口、出口4个出数及均衡条件导出了国内生产总值所满足的一阶线性非齐次差分方程,并求出了国内生产总值y1随时间t的变化规律,给出了y1稳定性的主分条件及单调条件,指目前宏观经济政策中出台的各项措施正是由y1的规律所制约 。 相似文献
80.
In this paper, the relationship between mechanical properties of 30 pieces of pure silk fabrics and the dress performance has been analyzed. With the methods of multifactor linear step regression and discrimination analysis, the judgment and prediction model of the performance have been established. 相似文献