检索结果-南通市图书馆

Effect of Solute Contents of Al-Ni-Sr Alloy on Glass Forming Ability and Thermal Stability

在线全文

学校读者我要写书评

暂无评论

journal of Rare Earths 2004年第Z2期22卷 73-77页

作者： Taek Soo Kim j K lee h j Kim j C Bae Advanced Materials R&D Center Korea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea

Glass forming ability (GFA) and structural characterization of a new amorphous Al-Ni-Sr alloy melt spun were investigated on the theory of the factors for the glass formation. The GFA was varied with the ratio of Ni to Sr in detail and successful amorphous phase dispersed with 2 ～ 5 nm precipitates was prepared from Al-Ni5-Sr3. Thermal stability and crystallization behavior of the amorphous phase were determined by continuous and isothermal heating technique on DCS, resulting that the crystallization occurs by the growth of fcc Al nanocrystals on the preexistent nuclei.

关键词： glass formation crystallization Al base amorphous alloys rapid solidification

Carbide Formation Process in Directionally Solidified MAR-M247 LC Superalloy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

journal of Materials Science & Technology 1999年第1期15卷 48-52页

作者： Chen, jian huang, Baiyun lee, j.h. Choe, S.j. lee, Y.T. Cent S Univ Technol Powder Met Res Inst Changsha 410083 Peoples R China Changwon Natl Univ Dept Met & Mat Sci Changwon 641773 South Korea Korea Inst Machinery & Mat Changwon 641010 South Korea

Carbide nucleation, growth and trapping behavior in directionally solidified MAR-M247 LC alloy and the corresponding mechanism have been investigated. Carbide forming element enrichment controls the carbide nucleation and the carbide growth behavior. If the carbide forming element enrichment and the nucleation sites are suitable, carbide nucleation can occur both above and below the liquids temperature. heterogeneous carbide nucleation is the preferred nucleation mechanism at low carbide forming element enrichment. Carbide growth occurs mainly at inter-secondary gamma dendrite arm area and lower part of the mushy zone. The carbides are subsequently trapped at these positions after growing to a certain size. Some carbides are only partially trapped by the solid-liquid interface and the carbide growth accelerates after being partially trapped. A critical growth rate exists between 2 multiplied by 10** minus **6 m/s and 5 multiplied by 10** minus **6 m/s. The carbide volume fraction decreases in the directionally solidified part at slow growth rate which is caused by the lack of suitable growth site and the low trapping ability of the solid-liquid interface. (Edited author abstract) 16 Refs.

关键词： Nickel alloys

Design of small-area multi-bit antifuse-type 1 kbit OTP memory

在线全文

学校读者我要写书评

暂无评论

journal of Central South University 2009年第3期16卷 467-473页

作者：李龙镇 lee j h KIM T h jIN K h PARK M h hA P B KIM Y h Department of Electronic Engineering Changwon National University Department of Computer Science and Technology Yanbian University

A multi-bit antifuse-type one-time programmable （OTP） memory is designed, which has a smaller area and a shorter programming time compared with the conventional single-bit antifuse-type OTP memory. While the conventional antifuse-type OTP memory can store a bit per cell, a proposed OTP memory can store two consecutive bits per cell through a data compression technique. The 1 kbit OTP memory designed with Magnachip 0.18 μm CMOS （complementary metal-oxide semiconductor） process is 34% smaller than the conventional single-bit antifuse-type OTP memory since the sizes of cell array and row decoder are reduced. And the programming time of the proposed OTP memory is nearly 50% smaller than that of the conventional counterpart since two consecutive bytes can be compressed and programmed into eight OTP cells at once. The layout area is 214 μm× 327 μ,, and the read current is simulated to be 30.4 μA.

关键词： multi-bit OTP programming time antifuse memory data compression

APPLICATION OF Ct-PARAMETER FOR CREEP-FATIGUE CRACK GROWTh WITh SLOW LOAD RISING CONDITION

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 1999年第1期12卷 22-30页

作者： lee, j.h. Yoon, K.B. Kim, Y.j. Back, U.B. Korea Inst of Nuclear Safety Taejon South Korea

Most of the assessment equations for Ct which is a wellknown fracture parameter characterizing high temperature crack growth rates, have limited applicability to constant load conditions after sudden loading. however, crack growth due to creep can also occur under load varying conditions when load rising time is so long that accumulated creep deformation near the crack tip is not *** this paper, the estimation equation of the Ctparameter which can be applied to the case of slow load rising, i.e., (Ct)r, is explained. And the correlation between (Ct)r at the end of the load increasing period and Ct at the beginning of the succeeding load hold period is discussed. Finite element analyses of several cases with various loading conditions were performed and results were presented to show the effectiveness of the proposed Ct estimation scheme. The general applicability of the equation is also discussed.

关键词： creep fatigue crack time dependent fracture mechanics Ctparameter,C*integral

C_2h_4-O_2混合气体直接起爆的临界能量

在线全文

学校读者我要写书评

暂无评论

爆炸与冲击 2012年第2期32卷 113-120页

作者：张博 lee j h S 白春华北京理工大学爆炸科学与技术国家重点实验室北京100081 Department of Mechanical Engineering McGill University

主要基于化学动力学和Ng模型,对C2h4-O2混合气体的爆轰胞格尺寸进行预测;结合lee表面积能量模型,预测物质在不同初始压力和化学当量比的条件下,直接起爆引起球面爆轰的临界起爆能量。直接起爆实验主要采用高压电点火提供起爆能量,起爆... 详细信息

主要基于化学动力学和Ng模型,对C2h4-O2混合气体的爆轰胞格尺寸进行预测;结合lee表面积能量模型,预测物质在不同初始压力和化学当量比的条件下,直接起爆引起球面爆轰的临界起爆能量。直接起爆实验主要采用高压电点火提供起爆能量,起爆能量通过放电过程中电流的输出信号确定。结果表明,理论预测与实验值较吻合。首先,通过化学动力学计算得出ZND模型的爆轰参数,利用Ng模型得出爆轰胞格尺寸与ZND诱导区长度之间的比例因数A在不同初始压力与当量比的条件下分别为:A=43.815(1+p1/p0)-0.123 71和A=8.531exp(φ/3.135)+28.644,在此基础上对爆轰胞格尺寸进行定量预测。胞格尺寸的理论预测与实验结果吻合。其次,把爆轰胞格尺寸作为中间特征参数并结合lee的表面积能量模型,提出可以预测临界起爆能量的定量模型,并得出C2h4-O2混合气体直接起爆的临界起爆能量与初始压力和化学当量比的参量拟合关系分别为Ec=0.332(p1/p0)-2.017和Ec=exp[3.951(φ-1.401)2-1.9]。

关键词：爆炸力学临界起爆能直接起爆 C2h4-O2混合气体胞格尺寸化学动力学电火花点火

在线全文

学校读者我要写书评

暂无评论

通过短线段来识别手写体汉字

图象识别与自动化 1993年第1期 11-21页

作者： lee,h－j 李桦

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

现生产柴油机二级平衡机构的研制

柴油机设计与制造 1989年第1期 12-18页

作者： lee,j.h. 徐仲良

CCR3和IL5RA基因多态性对哮喘患者嗜酸性粒细胞增高的遗传学影响(英文)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中华临床免疫和变态反应杂志 2008年第2期 152-153页

作者： lee j-h 文利平北京协和医院

两个因素可影响嗜酸性粒细胞的数目,分别是趋化因子受体(CCR3)和嗜酸性粒细胞生存调节因子(白细胞介素5,IL-5)。本研究对576例韩国哮喘患者和180名健康人的CCR3和IL-5受体α亚基基因的单核苷酸多态性(SNPs)与哮喘易感性及嗜酸性粒细胞... 详细信息

两个因素可影响嗜酸性粒细胞的数目,分别是趋化因子受体(CCR3)和嗜酸性粒细胞生存调节因子(白细胞介素5,IL-5)。本研究对576例韩国哮喘患者和180名健康人的CCR3和IL-5受体α亚基基因的单核苷酸多态性(SNPs)与哮喘易感性及嗜酸性粒细胞增高进行了相关性分析。CCR3基因的单核苷酸多态性都位于

关键词：嗜酸性粒细胞 IL5RA 哮喘患者 CCR3 基因多态性遗传多态性遗传学

韩国首尔通过都市农业减少交通领域的温室气体排放效应

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

城市规划学刊 2015年第5期 125-125页

作者： lee G G lee h W lee j h

韩国目前有91.15%的人生活在城市,全国范围内的城区中,49.2%的食品依赖于外部输入,从而产生了相当高的二氧化碳排放量。2007年的数据显示,韩国的人均食品外部输入量为543kg/人,高于英国、法国和日本,人均食品里程(Food mileage)为6143km... 详细信息

韩国目前有91.15%的人生活在城市,全国范围内的城区中,49.2%的食品依赖于外部输入,从而产生了相当高的二氧化碳排放量。2007年的数据显示,韩国的人均食品外部输入量为543kg/人,高于英国、法国和日本,人均食品里程(Food mileage)为6143km,是法国的4.2倍,英国的2倍。都市农业可以成为解决城镇化带来的环境问题的有效途径,它对温室气体减排的作用不仅仅在于生产本地食品,还可以减少食品从农场运输到城市的交通量从而减少排放。近年来韩国极力推动都市农业发展,很多地方自治实体颁布了相关的条例,

关键词：都市农业都市型农业交通领域大都市区首尔韩国