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Magnetic properties of DNA-templated Co/Cu naonoparticle chains

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Chinese Physics B 2010年第8期19卷 628-631页

作者：高有辉卫玲高春蕾夏卫星進藤大輔 Department of Physics Beijing Normal University The First institute of Oceanography institute of Multidisciplinary research for Advanced materials Tohoku University

According to ultraviolet （UV）-vis absorption spectra recorded in the DNA metallization process, DNA-templated Co/Cu binary nanoparticle chains are fabricated by incubating genome DNA of paralichthys olivaceus muscle in CoCl2 and CuCl2 mixture solution for 20 hours and reducing the complex for 2 hours. Transmission electron microscopy observation indicates that Co and Cu nanoparticles with 20 nm in diameter were randomly dispersed on the DNA template. The superconducting quantum interference device （SQUID） measurements display that the magnetic interaction between cobalt particles is greatly decreased by the copper particle. With increasing copper content, the coercivity of the systems enhance from 9 Oe to 100 Oe （1 Oe=79.5775 A/m）.

关键词： DNA-templated Co/Cu nanoparticle magnetic interaction

Growth and Spectroscopic Properties of Nd^(3+):Sr_3Gd_2(BO_3)_4 Crystal

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1039-1042页

作者： ZHANG Yan WANG Guo-Fu LIN Zhou-Bin ZHANG Li-Zhen School of materials science and Engineering Shanghai Institute of Technology Shanghai 200235 China Fujian institute of research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fufian 350002 China

This paper reports the growth, X-ray diffraction and spectroscopy of Nd3＋：Sr3Gd2（BO3）4 crystal. A Nd3＋：Sr3Gd2（BO3）4 crystal with dimensions of φ20 × 45 mm3 has been grown by the Czochralski method. Nd3＋：Sr3Gd2（BO3）4 crystal belongs to the orthorhombic system, space group Pnma （D2h） with a = 0.7401, b = 1.604 and c = 0.8755 nm. The absorption and emission spectra of Nd3＋：Sr3Gd2（BO3）4 were investigated. The absorption cross section oa is 3.11 × 10^-20cm2 at 808 nm. The absorption transition at 808 nm has an FWHM of 14 nm. The luminescence lifetime τf is 51.7 μs. The emission cross section oc at 1064 nm wavelength is 1.09 × 10^-19 cm2.

关键词： Nd3+:Sr3Gd2(BO3)4 crystal growth spectroscopic properties

Procedure for determining the number of thermal diffusion columns in square cascade for separation of Ne stable isotopes

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Nuclear science and Techniques 2023年第5期34卷 47-55页

作者： Fatemeh Mansourzadeh Mohammad Mahdi Shadman Javad Karimi Sabet Valiyollah Ghazanfari Nuclear Fuel Cycle research School Nuclear Science and Technology Research InstituteTehranIran

The thermal diffusion column represents one method of separating stable *** method is advantageous for smallscale operations because of the simplicity of the apparatus and small inventory,especially in gas-phase ***,it has attracted attention for its applicability in tritium and noble gas separation *** this study,the R cascade was used to design and determine the number of columns.A square cascade was adopted for the final design because of its flexibility,and calculations were performed to separate 20Ne and 22Ne *** the R cascades that enriched the Ne isotopes by more than 99%were investigated,the number of columns was determined,and the square cascade parameters were optimized using the specified ***,a calculation code“RSQ_CASCADE”was developed.A unit separation factor of three was considered,and the number of studied stages ranged from 10 to *** results showed that the column separation power,relative total flow rate,and required number of columns were linearly related to the number of *** separation power and relative total flow decreased and the number of columns increased as the stage number ***,a cascade of 85 columns is recommended to separate the stable Ne *** calculations yielded a 17-stage square cascade with five columns in each *** changing the stage cut,feed point,and cascade feed flow rate,the best parameters for the square cascade were determined according to the cascade and column separation *** the column separation power had a maximum value in cascade feed 50,it was selected for separating Ne isotopes.

关键词： Stable isotope Thermal diffusion Cascade Separation Neon

research on Ultrasonic Vibration Grinding of the Hard and Brittle materials

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Chinese Journal of Aeronautics 2006年第B12期19卷 9-13页

作者： YANG Xin-hong HAN Jie-cai ZHANG Yu-min ZUO Hong-bo ZHANG Xue-jun research Station on Material science and Engineering for Postdoctoral Fellows Harbin Institute of Technology Harbin 150001 China Centre for Composite materials Harbin Institute of Technology Harbin 150001 China

It is well known that grinding techniques are main methods to machine hard and brittle materials such as engineering ceramics. But the conventional grinding has many shortcomings such as poorer surface finish, quicker wear and tear of grinding tools, lower efficiency and so on. Ultrasonic vibration grinding （UVG） which combines ultrasonic machining and grinding emerged as a developing and promising technique in recent years. In this paper, experimental studies on UVG were conducted on several kinds of hard and brittle material by altering processing parameters such as vibration frequency and its amplitude, diamond abrasive grit size, cutting depth, feeding speed and rotary speed of tools. The experimental results show that alteration in any of above mentioned parameters will bring effects on the processed surface finish of these materials. Of them, the diamond abrasive grit size has the greatest. Moreover, conventional grinding experiments were also carried out on these materials. By comparison, it was found that the UVG is superior to the conventional method in terms of the ground surface quality, the working efficiency and the wear rate of tools.

关键词： ultrasonic vibration grinding (UVG) hard and brittle materials surface roughness wear extent

Emerging rechargeable aqueous aluminum ion battery:Status,challenges,and outlooks

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Nano materials science 2020年第3期2卷 248-263页

作者： Du Yuan Jin Zhao William Manalastas Jr Sonal Kumar Madhavi Srinivasan Energy research institute Nanyang Technological University637553Singapore School of materials science and Engineering Nanyang Technological University639798Singapore

Aluminum ion battery(AIB)technology is an exciting alternative for post-lithium energy *** based on ionic liquids have enabled advances in both cathode material development and fundamental understanding on ***,unlocking chemistry in rechargeable aqueous aluminum ion battery(AAIB)provides impressive prospects in terms of kinetics,cost,safety considerations,and ease of *** review the progress on AAIB,we discuss the critical issues on aluminum electrochemistry in aqueous system,cathode material design to overcome the drawbacks by multivalent aluminum ions,and challenges on electrolyte design,aluminum stripping/plating,solid-electrolyte interface(SEI)formation,and design of cathode *** review aims to stimulate exploration of high-performance AAIB and rationalize feasibility grounded on underlying reaction mechanisms.

关键词： Aluminum ion battery Aqueous aluminum ion battery Rechargeable Al stripping/plating SEI

Advances in graphene reinforced metal matrix nanocomposites:Mechanisms,processing,modelling,properties and applications

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Nanotechnology and Precision Engineering 2020年第4期3卷 189-210页

作者： Wenge Chen Tao Yang Longlong Dong Ahmed Elmasry Jiulong Song Nan Deng Ahmed Elmarakbi Terence Liu Hai Bao Lv Yong Qing Fu School of materials science and Engineering Xi'an University of TechnologyXi'an 710048PR China Advanced materials research Central Northwest Institute for Nonferrous Metal ResearchXi'an 710016PR China School of materials science and Engineering Northeastern UniversityShengyang 110819PR China Faculty of Engineering and Environment Northumbria UniversityNewcastle upon Tyne NE18STUK School of materials science and Engineering University of Science and Technology BeijingBeijing 100083PR China National Key Laboratory of science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China

Graphene has been extensively explored to enhance functional and mechanical properties of metalmatrix nanocomposites for wide-range applications due to their superior mechanical,electrical and thermal *** article discusses recent advances of key mechanisms,synthesis,manufacture,modelling and applications of graphene metal matrix *** main strengthening mechanisms include load transfer,Orowan cycle,thermal mismatch,and refinement *** technologies are discussed including some conventional methods(such as liquid metallurgy,powdermetallurgy,thermal spraying and deposition technology)and some advanced processing methods(such as molecular-level mixing and friction stir processing).Analytical modelling(including phenomenological models,semi-empirical models,homogenization models,and self-consistent model)and numerical simulations(including finite elements method,finite difference method,and boundary element method)have been discussed for understanding the interface bonding and performance characteristics between graphene and different metal matrices(Al,Cu,Mg,Ni).Key challenges in applying graphene as a reinforcing component for the metal matrix composites and the potential solutions as well as prospectives of future development and opportunities are highlighted.

关键词： Graphene Metal matrix composites Strengthening mechanism Synthesis method Modelling

Preparation and Characterization of Polyborosiloxanes and Their Blends with Phenolic Resin as Shapeable Ceramic Precursors

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Chinese Journal of Polymer science 2014年第2期32卷 187-196页

作者： Hong-ying Zhao 赵京波 Hao Li Tong Zhao Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education College of Materials Science and Engineering Beijing University of Chemical Technology Laboratory of Advanced Polymer materials Institute of Chemistry Chinese Academy Science

Two polyborosiloxanes （PBSis） with char yield up to 74.13% at 800 ℃ were synthesized by the direct polycondensation of boric acid with phenyltrimethoxysilane in diglyme. The PBSis were characterized by gel permeation chromatography, IR spectroscopy as well as ^1H-, ^29Si- and ^11B-NMR. PBSi modified phenol-formaldehyde resins （PBSi/PFs） were prepared at different PBSi/PF mass ratios and were cured at 150 ℃. The PBSi/PFs were characterized by IR spectroscopy, scanning electron microscopy, thermogravimetric analysis and tensile test. The results revealed that the cured PBSi/PFs had sea-island morphology and higher char yield than the common PF. PBSi/PF blend with PBSi/PF mass ratio of 0.4：1 had char yield up to 70.83% at 800 ℃. The PBSi/PFs had tensile strength similar to PF. The ceramization of PBSi/PFs was also studied. The silicon boron oxycarbide （SiBOC） ceramics formed were characterized by IR spectroscopy and elemental analysis. This method provided a valuable way to prepare easily shapeable polymer blends as ceramic precursors.

关键词： Polyborosiloxane Phenolic resin Preparation Ceramic precursors SiBOC ceramics.

Infrared Laser Pumped Green and Blue Laser Emissions from a Single Solid State Material Doped by Rare Earth Ions

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Journal of Rare Earths 2003年第3期21卷 307-314页

作者：黄艺东黄妙良陈雨金罗遵度 Fujian institute of research on the Structure of Matter Chinese Academy of Sciences College of materials science and Engineering Huaqiao University Quanzhou 362011 China

The possible ways and progress of infrared or red laser pumped green and blue laser emissions from a single solid state material doped by rare earth ions are outlined. The green and blue lasers realized from infrared laser pumped rare earth doped nonlinear laser crystals by means of self frequency conversion and from infrared laser pumped rare earth doped bulk, fiber and microsphere materials by means of frequency upconversion are introduced in detail. Other kinds of devices and methods are also compared. The typical nonlinear laser crystals such as YAl 3(BO 3) 4, GdAl 3(BO 3) 4, YCa 4O(BO 3) 3 , GdCa 4O(BO 3) 3, and the typical upconversion fluoride fibers are compared and analyzed. The major problems remaining to be solved and the developing trends in the area are also discussed.

关键词： optics solid state laser material blue and green lasers rare earth

Effect of deformation temperature and strain rate on semi-solid deformation behavior of spray-formed Al-70%Si alloys

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中国有色金属学会会刊：英文版 2005年第5期15卷 1125-1129页

作者：张迪杨滨张济山张永安熊柏青 State Key Laboratory for Advanced Metals and materials University of Science and Technology Beijing Beijing 100081 China General research institute for Nonferrous Metals Beijing 100088 China

Spray-formed Al-70%Si(mass fraction) alloys were deformed by compression in the semi-solid state. The effects of the deformation temperature, strain rate and the microstructure were studied. Two strain rates(1s -1and 0.1s -1) and six deformation temperatures (600℃, 720℃ , 780℃, 900℃, 1000℃ and 1100℃) were chosen. The stress—strain curve exhibits a peak at low strain and then decreases to a plateau before it starts to increase again as the strain increases. The stress required for deformation at lower strain rate and at higher deformation temperatures is less than those at higher strain rate and at lower deformation temperatures. Four mechanisms of semi-solid deformation can be used to explain the different behaviors of the stress—strain curves under different conditions.

关键词：铝硅合金固体相变形处理热量摩擦系数