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The April 14th, 2010 Yushu earthquake, a devastating earthquake with foreshocks

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science china Earth sciences 2010年第6期53卷 791-793页

作者： NI SiDao1, WANG WeiTao2 & LI Li3 1 School of Earth and Space sciences, university of science and technology of china, Hefei 230026, china 2 Institute of Geophysics, china Earthquake Administration, beijing 100081, china 3 national Earthquake Infrastructure service, china Earthquake Administration, beijing 100036, china School of Earth and Space sciences University of Science and Technology of China Hefei China Institute of Geophysics China Earthquake Administration Beijing China national Earthquake Infrastructure service China Earthquake Administration Beijing China

In the early morning of April 14th, 2010, a strong earth- quake (Ms7.1, http://***; Mw6.9, http://neic. ***) occurred in Yushu district, Qinghai Province, china. More than 2000 lives were lost and over 100000 injured,

关键词： Figure Yushu earthquake a devastating earthquake with foreshocks The April 14th 2010 very than

Electronic packaging materials prepared by powder injecting molding and pressure infiltration process

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Rare Metals 2007年第6期26卷 625-629页

作者： YIN Fazhang GUO Hong JIA Chengchang XU Jun ZHANG Ximin ZHU Xuexin national Engineering and technology Research center for Nonferrous Metals Composites Beijing General Research Institute for Nonferrous Metals Beijing 100088 China materials science and Engineering School University of Science and Technology Beijing Beijing 100083 China

AlSiCp （65 vol.% SiC） electronic packaging materials were manufactured by powder injection molding （PIM） and pressure infiltration process in order to obtain near net-shaped parts. SiCp preformed compacts obtained by pre-sintering process at 1150 K have high strength and good appearance, and the ratio of open porosity to total porosity is nearly 98%. The relative density of composites is bigger than 99%. The thermal conductivity of A1SiCp composites fabricated by this method is 198 W·m^-1·K^-1, and the coefficient of thermal expansion （CTE） is 8.0 × 10^-6/K （298 K）.

关键词： composites aluminum microstructure thermal conductivity

Characterization and Comparison of Conducting Polyaniline Synthesized by Three Different Pathways

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Journal of Wuhan university of technology(materials science) 2011年第6期26卷 1068-1072页

作者：董超芳 Corrosion & Protection center University of Science and Technology Beijing Key Laboratory for Corrosion and Protection of Ministry of Education

The conducting polyaniline （PANI） prepared by three chemical oxidative polymerization pathways including microemulsion, emulsion and aqueous solution methods were studied and compared. Their structures, morphologies and properties were characterized using FT-IR, XRD, TEM and TGA. PANI particles formed in aqueous solution have a smallest size and doping HCl enables to increase their conductivity. In contrast, PANI particles prepared by emulsion method have the highest thermal stability and conductivity and more ordered morphology. Rather different from these two methods, microemulsion approach allows forming nanocomposite PANI with tube-like nanostructure.

关键词： nano materials polymers polyaniline

EFFECT OF SnO_2 ADDITION ON THE service LIFE AND ELECTROCHEMICAL PROPERTIES OF Ti/IrO_2,+Ta_2O_5 ANODES IN PHENOLSULFONIC ACID SOLUTION

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Acta Metallurgica Sinica(English Letters) 2000年第4期13卷 937-943页

作者： J.M. Hu H.M. Meng D.B. Sun S.J. Zhang J.X. Wu and D.J. Yang beijing Corrosion and Protection center, Open Laboratory of Corrosion, Erosion and Surface technology, university of science and technology beijing, beijing 100083, china beijing Univ of science and Technology Beijing China

service life of two different oxide anodes in phenolsulfonic acid (PSA) solution was investigated by accelerated electrolysis. The durability of Ti/IrO_2+Ta_2 O_5 anode increased by the addition of SnO_2 in the mixed oxides. The degradation mechanisms of Ti/IrO_2+ Ta_2 O_5 and Ti/IrO_2 +Ta_2 O_5 +SnO+2 anodes were different. It was shown from the observation of scanning electron microscopy (SEM) and the electrochcmical measurement that, the deactivation of Ti/IrO_2 + Ta_2 O_5 anode was due to the build-up of an organic film on surface. The growth of the covered film on surface was restricted by addition of SnO_2, which resulted in increasing of the service life of anodes. The over-potential for oxygen evolution on Ti/IrO_2 +Ta_2 O_5 electrode increased after doping SnO_2, and the intermediate products of PSA building-up on the surface was much more rapidly oxidized. Meanwhile, a certain part of the surface oxide deposit entered into the solution leading to loss of oxides, which resulted in degradation of Ti/IroO_2 + Ta_2 O_5 anode containing SnO_2 component.

关键词： metal oxide anode IrO_2 + Ta_2 O_5 IrO_2 + Ta_2 O_5 +SnO_2 phenolsulfonic acid degradation

Engineering of drug nanoparticles by HGCP for pharmaceutical applications

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Particuology 2008年第4期6卷 239-251页

作者： Ting-Ting Hua, Jie-Xin Wanga, Zhi-Gang Shena, Jian-Feng Chena,b, a Key Lab for Nanomaterials, Ministry of Education, beijing university of Chemical technology, beijing 100029, china b Research center of Ministry of Education for High Gravity Engineering and technology, beijing university of Chemical technology, beijing 100029, china Key Lab for Nanomaterials Ministry of Education Beijing University of Chemical Technology Beijing 100029 China Research center of Ministry of Education for High Gravity Engineering and technology Beijing University of Chemical Technology Beijing 100029 China

This paper reviews our work on the fundamental principles of high gravity controlled precipitation (HGCP) technology, and its applications in the production of drug nanoparticles, which was carried out in a rotating packed bed (RPB). Several kinds of drug nanoparticles with narrow particle size distributions (PSDs) were successfully prepared via HGCP, including the 300-nm Cefuroxime Axetil (CFA) particles, 200–400-nm cephradine particles, 500-nm salbutamol sulfate (SS) particles (100 nm in width), and 850-nm beclomethasone dipropionate (BDP) particles, etc. Compared to drugs available in the current market, all the drug nanoparticles produced by HGCP exhibited advantages in both formulation and drug delivery, thus improving the bioavailability of drugs. HGCP is essentially a platform technology for the preparation of poorly water-soluble drug nanoparticles for oral and injection delivery, and of inhalable drugs for pulmonary delivery. Consequently, HGCP offers potential applications in the pharmaceutical industry due to its cost-effectiveness, efficient processing and the ease of scaling-up.

关键词： High gravity controlled precipitation Rotating packed bed Drug nanoparticle Poorly water-soluble drug Inhalable drug

Decoding algorithms for shortened-extended turbo product codes in WiMAX systems

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science in china(Series F) 2009年第12期52卷 2415-2423页

作者： XU ChangLong1,3,4, YANG Wei1,2 & YE WeiChen4 1 State Key Laboratory of Networking and Switching technology, beijing university of Posts and Telecommunications, beijing 100044, china 2 State Key Laboratory of Rail Traffic Control and safety, beijing Jiaotong university, beijing 100044, china 3 national Mobile Communications Research Laboratory, Southeast university, Nanjing 210096, china 4 Intel Corporation, beijing Kerry center, Guanghua Road 1, beijing 100020, china State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications State Key Laboratory of Rail Traffic Control and safety Beijing Jiaotong University national Mobile Communications Research Laboratory Sout

The component codes of turbo product codes in WiMAX systems are extended Hamming codes and single parity check codes as well as their shortened forms, In this paper, three novel iterative decoding algorithms based on Chase, MAP algorithms and their combination are proposed for shortened-extended turbo product codes. The iterative decoding algorithm based on Chase algorithm is proposed to reduce the decoding complexity without any performance loss. An efficient MAP algorithm is then proposed to decode the component codes of shortened single parity check codes and shortened-extended Hamming codes. A comprehensive performance comparison of the proposed decoding schemes is conducted for three typical classes of turbo product codes in WiMAX OFDMA systems. The suitable decoding algorithms are recommended for different classes based on the simulation results.

关键词： block code product code iterative decoding

UV-induced Self-initiated Graft Polymerization of Acrylamide onto Poly(ether ether ketone)

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Chemical Research in Chinese Universities 2012年第1期28卷 162-165页

作者： CHEN Rui-chao, SUN Hui, LI Ang and XU Guo-zhi College of materials science and Mechanical Engineering, national center for Quality Supervision and Test of Plastic Products, beijing technology and Business university, beijing 100048, P. R. china College of materials science and Mechanical Engineering National Center for Quality Supervision and Test of Plastic Products Beijing Technology and Business University Beijing 100048

Photo-grafting of hydrophilic monomer was used to enhance the hydrophilicity of poly（ether ether ketone）（PEEK） with the aim of extending its applications to biological fields. PEEK sheets were surface modified by grafting of acrylamide（AAm） with ultraviolet（UV） irradiation in the presence or absence of benzophenone（BP）. The effects of BP, irradiation time and monomer concentration on the surface wettability of PEEK were investigated. Characteriza tion of modified PEEK using scanning electron microscopy（SEM）, energy-disperse spectrometer（EDS） and water contact angle measurements shows that AAm was successfully grafted on PEEK surface both in presence and absence of BP. With the increase in irradiation time and monomer concentration, contact angles decrease to as low as 30°, demonstrating a significant improvement of surface hydrophilicity. In agreement with the decrease in contact angle, under identical conditions, the nitrogen concentration increases, suggesting the increase in grafting degree of the grafting polymerization. This investigation demonstrates a self-initiation of PEEK due to its BP-like structure in the backbone of the polymer. Though the graft polymerization proceeds more readily in the presence of BP, the self-initiated graft polymerization is clearly observed.

关键词： Poly(ether ether ketone)(PEEK) UV-grafting Surface modification Self-initiation Graft polymerization

FORMATION OF RECRYSTALLIZATION TEXTURE WITH ROLLING ORIENTATION IN Al-1.3%Mn ALLOY

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中国有色金属学会会刊：英文版 1998年第3期8卷 8-17页

作者： Yang Ping , O. Engler and G. Gottstein Department of materials science and Engineering, university of science and technology beijing, beijing 100083, P. R. china Los Alamos national Laboratory, center for materials science, Mail St

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｃｏｍｍｅｒｃｉａｌｐｕｒｅＡｌ（１ｘｘｘｓｅｒｉｅｓ）ｗｉｔｈＦｅａｎｄＳｉ，ｔｈｅｒｅｃｒｙｓｔａｌｉｚａｔｉｏｎｔｅｘｔｕｒｅｗｉｔｈｒｏｌｉｎｇｏｒｉｅｎｔａｔｉｏｎ，ｉｅｔｈｅ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｃｏｍｍｅｒｃｉａｌｐｕｒｅＡｌ（１ｘｘｘｓｅｒｉｅｓ）ｗｉｔｈＦｅａｎｄＳｉ，ｔｈｅｒｅｃｒｙｓｔａｌｉｚａｔｉｏｎｔｅｘｔｕｒｅｗｉｔｈｒｏｌｉｎｇｏｒｉｅｎｔａｔｉｏｎ，ｉｅｔｈｅＲｔｅｘｔｕｒｅ｛１２４｝〈６１２...

关键词： recrystallization texture AlMn ODF

Electrical characteristics of Pt-ZnO Schottky nano-contact

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 64-67页

作者： SHAO ZhengZheng , ZHANG XueAo, WANG XiaoFeng & CHANG ShengLi center of materials science, College of science, national university of Defense technology, Changsha 410073, china national university of Defense technology Center of Materials Science College of Science Changsha China (GRID:grid.412110.7) (ISNI:***)

The electrical characteristics of Pt-ZnO Schottky nano-contact have been studied. Well aligned ZnO nanorod arrays were synthesized by two-step wet-chemical method. A Pt-coated conducting probe of atomic force microscope was placed on the head face of the ZnO nanorod, thereby forming a Pt-ZnO nano-contact. The I-V characteristic curve shows that the Pt-ZnO nano-contact exhibits rectifying effect, like a Schottky diode with an ideality factor of 3.2 and a reverse-bias breakdown voltage more than -10 V. The study suggests that a high electric field is induced on the ZnO beneath the contact point when a bias voltage is applied, hence, the Schottky barrier thickness is decreased, and results in easier tunneling across the Pt-ZnO interface and a large ideality factor.

关键词： ZnO nanorod Schottky contact ideality factor