检索结果-南通市图书馆

Relationship between the orientation of texture and heteroepitaxy of diamond and related materials films on silicon single crystal and the valence electron structure of the interface

引用

Science China(Technological Sciences) 2007年第5期50卷 664-673页

作者： LI ZhiLin LI ZhiFeng HUANG Qin College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

Diamond and cubic boron nitride films have already been applied practically be- cause of their excellent properties. The specific orientations of the films have spe- cial meaning on their application in optics and microelectronics fields. In this paper, the relative electron density differences of the interface between the different crystal planes of silicon substrate and those of diamond and cubic boron films are calculated with the empirical electron theory in solids and molecules. Analyses on the calculation results show that in the range of the researched films, the smaller the relative electron density difference between the film and the substrate is, the stabler the film is in thermodynamics. Therefore, the electron density difference is the essential factor of determining the orientation of the texture and heteroepitaxy of the films. The deductions accord well with the experimental facts. The calcula- tion methods and the theory not only provide a new angle of view for the research of the growth mechanism of diamond film and cubic boron nitride film on the sili- con substrate, but also provide a possible direction for the prediction of the orien- tation of other films.

关键词： films, interface electron density, texture, heteroepitaxy, diamond, cubic boron nitride

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Discovery and analysis of ultra-micro grinding grain texture in slipping lamellae of ductile-brittle zone

引用

Science China Earth Sciences 2004年第3期47卷 265-271页

作者： GE Heping1, SUN Yan1, LU Xiancai1, ZHU Wenbin1, GUO Jichun1, LIU Deliang2 & Chi-yuen Wang3 1. Department of Earth Sciences, Nanjing University, State Key Laboratory of Mineral Deposit, Nanjing 210093, China 2. Department of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China 3. Department of Geology and Geophysics, University of California, Berkeley, CA 94720, USA Department of Earth Sciences Nanjing University State Key Lab. of Mineral Deposit Nanjing 210093 China Dept. of Earth and Space Sciences Univ. of Science/Technology of China Hefei 230026 China Department of Geology and Geophysics University of California Berkeley CA 94720 United States

Based on the observation of the deep bore cores sampled from the State of Cali-fornia, USA, preferred arranged particulate concentration belts were found in the ultra-slipping lamellae. And the same phenomenon was found again later in the bore cores from the petroleum basin in the Northern Shaanxi Province. It may be the product of the dynamic processes involv-ing tumbling, grinding and compresso-shearing functions, so the spherical particulates with ul-tra-size of nm and mm are called grinding grain. The formation of the grinding grains is related with the ductile-brittle deformation, the lateral pressure of the slipping, and the very low grade of dynamic metamorphism of the rocks. Based on the systematic analysis, it is indicated that some elements like Nb and Ta are enriched in the grinding grains in the granitic rocks because of the chemical differentiation, and that the slipping lamellae bearing grinding grains in mudstone with smear efficiency prove a perfect seal for oil and gas reservoirs. Meanwhile, the paper provides bases for the studies on the fast stick-slip movement and shear paradigm.

关键词： slipping lamellae, grinding grain texture, ductile-brittle deformation, smear efficiency.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental study of surface texture and resonance mechanism of booming sand

引用

Science China Earth Sciences 2007年第9期50卷 1351-1358页

作者： QU JianJun1, ZHANG KeCun1, SUN Bo2, JIANG ShengXiang3, DONG GuangRong1, ZU RuiPing1 & FANG HaiYan 1 Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China 2 Shanghai Institute of Polar Regions, Shanghai 210000, China 3 Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shanghai Institute of Polar Regions Shanghai 210000 China Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The sound-producing mechanism of booming sand has long been a pending problem in the blown sand physics. Based on the earlier researches, the authors collected some silent sand samples from Teng- ger Desert, Australian Desert, Kuwait Desert, beaches of Hainan Island and Japanese coast as well as the soundless booming sand samples from the Mingsha Mountain in Dunhuang to make washing ex- periments. In the meantime the chemical corrosion experiment of glass micro-spheres, surface coating experiment and SEM examination were also conducted. The experimental results show that the sound production of booming sand seems to have nothing to do with the presence of SiO2 gel on the surface of sand grains and unrelated to the surface chemical composition of sand grains but is related to the resonance cavities formed by porous (pit-like) physical structure resulting from a number of factors such as wind erosion, water erosion, chemical corrosion and SiO2 gel deposition, etc. Its resonance mechanism is similar to that of Hemholz resonance cavity. Under the action of external forces, nu- merous spherical and sand grains with smooth surface and porous surface are set in motion and rub with each other to produce extremely weak vibration sound and then become audible sound by human ears through the magnification of surface cavity resonance. However the booming sands may lose their resonance mechanism and become silent sand due to the damping action caused by the invasion of finer particles such as dust and clay into surface holes of sand grains. Therefore, clearing away fine pollutants on the quartz grain surface is an effective way to make silent sand emit audible sound.

关键词： booming sand, surface texture, quartz grain, sound-producing mechanism, Hemholz resonance cavity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Measurement and Simulation of Grain Size in Strong textured and Coarse-Grained Metal Sheets

引用

Journal of Materials Science & Technology 2003年第Z1期19卷 115-116页

作者： Leng CHEN Weimin MAO Yongning YU Huiping FENG Department of Materials University of Science and Technology Beijing Beijing 100083 China Department of Materials University of Science and Technology Beijing Beijing 100083 China Department of Materials University of Science and Technology Beijing Beijing 100083 China Department of Materials University of Science and Technology Beijing Beijing 100083 China

An X-ray diffractometer that equipped with a two-dimensional detector is used for developing the technique of grainsize measurement for strong textured and coarse-grained Si steel sheet. The method is based on the concept thatthe position of diffraction spots depends on the orientation of individual grains. The two-dimensional detector hasthe ability to collect abundant diffraction information in seconds, thus it can be determined rapidly and accuratelywhether a series of diffraction spots come from the same grain. The experimental results show that this method canbe used for measuring grain size and its distribution in strong textured and coarse-grained metal sheets.

关键词： Grain size, texture, Two-dimensional detectorLeng

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：