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A Modified Integrated Model of the Internal Structure of Chinese Cultured Pearls

13th Asian Chemical Congress

作者： Hong-De Ye and Hong Yan~* state Key laboratory of Coordination Chemistry,School of Chemistry and Chemical engineering, nanjing university,nanjing 210093,china

The reaction of CpCoCOI with Li[SC(BH)]affords a 16e CpCo half-sandwich complex(1) containing a chelating 1,2-dicarba-closo-dodecaborane-1,2-dichalcogenolate *** reaction of 1 with 1-ferrocenyl-2-propyn-1-one(2)leads ... 详细信息

关键词： Cobalt Half-sandwich complex Carborane Ferrocenylpropynone

来源： cnki会议评论

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Journal of Wuhan university of Technology(materials science) 2011年第3期26卷 510-513页

作者：马红艳 Key laboratory of Nonferrous Metals and New material Processing Technology Ministry of EducationCollege of Materials Science and EngineeringGuangxi University

Optical and micro-infrared microscope were used to observe the internal structure and mineral composition of high and low quality Chinese seawater and freshwater cultured *** clearly reveal that aragonite and calcite are found in seawater cultured pearls,but vaterite is not *** contrast,vaterite and aragonite are found in freshwater cultured pearls,but calcite is not *** on our analysis and observations of the internal structure of high and low quality cultured pearls,a modified integrated model of the internal structure of Chinese cultured pearls was *** revisions to the previous model focus on significant differences within the prismatic layer of Chinese cultured pearls.

关键词： cultured pearls aragonite vaterite calcite integrated model

Cellulose conversion to polyols on supported Ru catalysts in aqueous basic solution

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science china Chemistry 2010年第7期53卷 1476-1480页

作者： DENG TianYin,SUN JiYing & LIU HaiChao Beijing national laboratory for Molecular sciences,state Key laboratory for Structural Chemistry of Stable and Unstable Species Green Chemistry Center,College of Chemistry and Molecular engineering,Peking university,Beijing 100871,china 1. Beijing national laboratory for Molecular sciences State Key Laboratory for Structural Chemistry of Stable and Unstable Species Peking University Beijing 100871 China2. Green Chemistry Center College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

It is of great significance and challenge to achieve direct conversion of cellulose to specific polyols,e.g.,ethylene glycol and propylene *** such selective conversion,a novel one-pot approach was studied by combination of alkaline hydrolysis and hydrogenation on supported Ru catalysts.A wide range of bases including solid bases,e.g.,Ca(OH)2 and La2O3,and phosphate buffers were examined in the cellulose reaction in water,and the cellulose conversions and polyol products depended largely on the basicity or pH values in the aqueous *** glycol,1,2-propanediol,and especially 1,2,5-pentanetriol were obtained with selectivities of 15%,14% and 22%,respectively,at 38% cellulose conversion at pH 8 in phosphate buffer *** preliminary results provide potentials for efficient conversion of cellulose to targeted polyols by using the advantages of bases.

关键词： cellulose polyols Ru catalysts solid bases aqueous basic solutions

Crystal formation and growth mechanism of inorganic nanomaterials in sonochemical syntheses

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中国科学:化学 2012年第11期42卷 1645-1645页

作者： GENG Jun 1,2,JIANG LiPing 1 & ZHU JunJie 1 1 state Key laboratory of Analytical Chemistry for Life science School of Chemistry and Chemical engineering,nanjing university,nanjing 210093,china2 department of Chemistry,Jiangsu Institute of Education,nanjing 210013,china state Key laboratory of Analytical Chemistry for Life science School of Chemistry and Chemical engineering nanjing university nanjing 210093 china department of Chemistry Jiangsu Institute of Education nanjing 210013 china

A clear understanding of the nucleation,growth,coarsening,and aggregation processes of nanomaterials is necessary to enable the preparation of highly controlled *** wet chemical synthetic methods,ultrasound-assisted preparation has become an important tool in material *** formation and crystal growth mechanism under ultrasound is special compared with other wet chemical synthetic *** this review,we discussed the chemical and physical effect of ultrasound and summarized the ultrasonic effect on *** sonolysis of water and the cavitation-induced microjet impact and shockwave are the two key factors in the sonochemical formation of inorganic *** ultrasonic-assisted Ostwald ripening and oriented attachment processes have been reviewed for the possible crystal growth mechanisms in the fabrication of inorganic nanostructures.

关键词： nanoparticles nanocrystalline synthesis sonochemistry crystal growth formation mechanism

Size and distribution of Te inclusions in detector-grade CdZnTe ingots

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Progress in Natural science:materials International 2011年第1期21卷 66-72页

作者： Ya-dong XU~(1,2),Wan-qi JIE~1,Yi-hui HE~1,Rong-rong GUO~1,Tao WANG~1,Gang-qiang ZHA~1 1.state Key laboratory of solidification Processing,Northwestern Polytechnical university,Xi'an 710072,china 2.School of materials science and engineering,Northwestern Polytechnical university,Xi'an 710072,china [a] state Key laboratory of solidification Processing Northwestern Polytechnical University Xi'an 710072 China [b] School of materials science and engineering Northwestern Polytechnical University Xi'an 710072 China

To observe the Te inclusions distribution along the axial direction of CdZnTe ingots,batches of as-grown detector-grade CdZnTe crystals grown by vertical Bridgman method,were investigated using IR transmission ***,there is not a rigorous regularity for the micron-scale Te inclusions distribution along the axial direction of CdZnTe ingots according to the measurements of the present *** size and distribution variations of Te inclusions are attributed to the growth velocity, furnace temperature situation and morphological changes at the liquid-solid interface during crystal *** mobility lifetime products were discussed in conjunction with Te ***,no strict correlations are identified between the sizes and concentrations of Te inclusions and theγ-ray spectroscopy *** defects in CdZnTe crystals,which are not visible via IR transmission imaging,potentially attribute to CdZnTe detectors performance degrades.

关键词： CdZnTe Te inclusions IR imaging crystallization interface

Phenomenon of “contact guidance” on the surface with nano-micro-groove-like pattern and cell physiological effects

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Chinese science Bulletin 2009年第18期54卷 3200-3205页

作者： ZHOU Feng 1,2, YUAN Lin 1,3, HUANG He 1,2 & CHEN Hong1,2 1 state Key laboratory of Advanced Technology for materials Synthesis and Processing, Wuhan 430070, china 2 School of materials science and engineering, Wuhan university of Technology, Wuhan 430070, china 3 Biomedical materials Research Center, Wuhan university of Technology, Wuhan 430070, china state Key laboratory of Advanced Technology for materials Synthesis and Processing Wuhan 430070 China School of materials science and engineering Wuhan University of Technology Wuhan 430070 China Biomedical materials Research Center Wuhan University of Technology Wuhan 430070 China

The topography of material surface has important influence on cell behavior and physiological functions. Groove-like pattern has drawn much attention among various patterns, due to the phenomenon of "contact guidance" induced by this kind of topography. This review mainly focuses on "contact guidance" formation as well as its influence on cell behavior and physiological effects. The possible mechanisms of "contact guidance" formation were discussed. The research trend and the potential applications were also suggested.

关键词：细胞行为生理功能材料表面逻辑效应触指纳米微米生理效应

Extended multiscale finite element method for mechanical analysis of heterogeneous materials

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Acta Mechanica Sinica 2010年第6期26卷 899-920页

作者： Hong-Wu Zhang·Jing-Kai Wu·Jun L·Zhen-Dong Fu state Key laboratory of Structural Analysis for Industrial Equipment, department of engineering Mechanics, Faculty of Vehicle engineering and Mechanics, Dalian university of Technology,Dalian 116024,china state Key laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Faculty of Vehicle Engineering and Mechanics Dalian University of Technology Dalian China

An extended multiscale finite element method （EMsFEM） is developed for solving the mechanical problems of heterogeneous materials in *** underlying idea of the method is to construct numerically the multiscale base functions to capture the small-scale features of the coarse elements in the multiscale finite element *** the basis of our existing work for periodic truss materials, the construction methods of the base functions for continuum heterogeneous materials are systematically introduced. Numerical experiments show that the choice of boundary conditions for the construction of the base functions has a big influence on the accuracy of the multiscale solutions, thus,different kinds of boundary conditions are proposed. The efficiency and accuracy of the developed method are validated and the results with different boundary conditions are verified through extensive numerical examples with both periodic and random heterogeneous ***, a consistency test of the method is performed numerically. The results show that the EMsFEM can effectively obtain the macro response of the heterogeneous structures as well as the response in micro-scale,especially under the periodic boundary conditions.

关键词： Extended multiscale finite element method Heterogeneous material Base function Downscaling computation

Numerical and experimental investigation of the fracture behavior of shock loaded alumina

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science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 244-252页

作者： REN HuiLan1,SHU XueFeng2 & LI Ping3 1 state Key laboratory of Explosion science and Technology,Beijing Institute of Technology,Beijing 100081,china 2 Institute of Applied Mechanics and Biomedical engineering,Taiyuan university of Technology,Taiyuan 030024,china 3 Labroratory for Shock Wave and Detonation Physics Research,Institute of Fluid Physics,CAEP,Mianyang 610059,china 1. state Key laboratory of Explosion science and Technology Beijing Institute of Technology Beijing 100081 China2. Institute of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology Taiyuan 030024 China3. Labroratory for Shock Wave and Detonation Physics Research Institute of Fluid Physics CAEP Mianyang 610059 China

Plate impact expeiments are conducted to investigate the dynamic behavior of alumina by using one stage light gas gun. A ve-locity interferometer system for reflectors (VISAR) is used to obtain Hugoniot elastic limit and the free surface velocity profile,which consists of an elastic wave followed immediately by a dispersive inelastic wave. The stress histories under different impact velocities are measured by in-material manganin gauges. Based on the experimental data a Hugoniot curve is fitted,which shows the compressive characteristics that alumina changes typically from elastic to "plastic" ,and under higher pressure it will be transferred to similar-fluid state. The turning point of the Hugoniot curve from a high pressure region to a low pressure region is about 11.4 GPa. The fracture process of alumina is simulated by way of finite element code. After the analysis of the fracture mechanism,the numerical results show an important role played by the nucleation and the growth of the cracks in the macro-scopic fracture of the alumina target. The numerical predictions of stress histories are compared with the experimental results,which indicates consistency between them.

关键词： plate impact experiment hugoniot curve fracture characteristics numerical simulation

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Zn-Al二元合金熔化过程的低频内耗研究

物理学报 2002年第3期51卷 625-628页

作者：陈刚朱震刚江苏理工大学材料科学与工程学院中国科学院固体物理研究所内耗与固体缺陷开放研究实验室合肥230031 中国科学院固体物理研究所内耗与固体缺陷开放研究实验室

利用强迫振动扭摆方法对Zn Al二元合金熔化过程的低频内耗进行了研究 .结果表明 ,Zn Al二元合金熔化过程的内耗峰与其固态相变内耗峰的特征有较大差异 .结合该合金熔化过程的微观结构变化 ,初步分析了内耗峰的形成机理 .

关键词： Zn-Al合金低频内耗熔化锌铝二元合金内耗峰微观结构

Theoretical research on electron beam modulation in a field-emission cold cathode electron gun

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Chinese Physics B 2014年第3期23卷 550-554页

作者：李兴兴袁学松张宇鄢扬 School of Physical Electronics University of Electronic Science and Technology of China state Key laboratory of Optoelectronic materials and Technologies and Guangdong Province Key Laboratory of Display Material and TechnologySchool of Physics and Engineering Sun Yat-sen University

In order to develop miniaturized and integrated electron vacuum devices, the electron beam modulation in a field- emission （FE） electron gun based on carbon nanotubes is researched. By feeding a high-frequency field between the cathode and the anode, the steady FE electron beam can be modulated in the electron gun. The optimal structure of the electron gun is discovered using 3D electromagnetism simulation software, and the FE electron gun is simulated by PIC simulation software. The results show that a broadband （74-114 GHz） modulation can be achieved by the electron gun with a rhombus channel, and the modulation amplitude of the beam current increases with the increases in the input power and the electrostatic field.

关键词： carbon nanotubes cold cathode field emission electron gun