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Electrode materials for advanced lithium-ion batteries

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Electrode materials for advanced lithium-ion batteries

Investigation on growth and laser properties of new laser crystal Nd:Gd_(0.8)La_(0.2)VO_4

第十二届中国固态离子学学术会议

作者： S.X. Dou Institute for superconducting & electronic materials, university of wollongong, nsw 2.2., australia

Several types of cathode materials and anode materials have been developed for lithium-ion battery applications. Layered Li[Li0.3Cr0.1Mn0.6]O2 cathode material with a hexagonal structure wassynthesized by a solid-state reaction. The structural changes of this material were studied using a synchrotron based in situ x-ray diffraction technique during charge/discharge cycles. A series of LiMxFe1-xPO4 (M = Mg, Zr, Ti) phosphates were synthesized via a sol-gel method, followed by thermal treatment at medium temperature. HRTEM analysis reveals that a layer of amorphous carbon was coated on the surface of the LiMxFe1-xPO4 particles, which substantially increases the electronic conductivity of the bulk of LiMxFe1-xPO4 electrodes. Near full capacity (170 mAh/g) was achieved at the C/8 rate at room temperature for LiMxFe1-xPO4 electrodes. The doped LiMxFe1-xPO4 electrodes demonstrated better electrochemical performance than that of undoped LiFePO4 at high charge/discharge rate. Nanocrystalline Si-mesocarbon microbeads (MCMB) composite anode materials were prepared by ball milling. SEM observation shows that the spherical shape of MCMB particles can be retained via moderate ball-milling. It was found that ball-milling conditions have an impact on the capacity and cyclability of nanocrystalline Si-MCMB composites. The optimised Si-MCMB composite anode demonstrated a reversible capacity of 1066 mAh/g with good cyclability. A reaction model has been proposed to explain the reaction mechanisms of lithium insertion and extraction in the Si-MCMB electrode. WS2 nanotubes were synthesised by sintering amorphous WS2 at high temperature under flowing hydrogen. High resolution TEM observation revealed that the as-prepared WS2 nanotubes have an open end with an inner hollow core of about 4.6 nm. We studied the lithium intercalation behaviour of WS2 nanotubes. The WS2 nanotubes demonstrated a stable cyclability in a wide voltage range (0.1 - 3.1 V versus Li/Li+). The nanotubes could provid

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Chinese Science Bulletin 1999年第9期44卷 863-864页

作者： ZHANG Huaijin , MENG Xianlin , ZHU Li ZHANG Hongzhen , WANG Pu , Judith Dawes , WANG Changqing and Y. T. ChowInstitute of Crystal materials and National Laboratory of Crystal materials , Shandong university , Jinan 250100, China Center for Lasers and Applications , Macquarie university , nsw2109, australia Department of electronic Engineering , City university of Hong Kong , China Institute of Crystal materials and National Inboratory of Crystal materialsr Shandng Unitvrsity Jinan China Center for Lasers and Applicatwns Macquarie Uniuersity Australia Department of electronic Engineering City University of Hong Kong China

LASER-DIODE （LD） pumped solid-state lasers have a variety of applications in military, industry, medical treatment and scientific researches due to their high stability, compactness, high efficiency and long lifetime, and become one of the hot points in the laser field. In this field, Nd: YVO4 laser has been commercialized. Nd:GdVO4 crystal has a big absorption coefficient, high thermal conductivity, and excellent laser properties. Nd: Gd0.5La0.5VO4 crystal formed by La3+ ions replacing some Gd3+ ions in Nd:GdVO4 has larger FWHM （full width at half maximum） than Nd: GdVO4 crystal. To combine the merits of Nd : GdVO4 and Nd : Gd0.5 La0.5 VO4, we grow the crystal doped with 20% La (Nd: Gd0.8La0.2VO4, and study its properties. Now we introduce the laser and spectroscopic properties of the crystal in brief.

关键词： Nd Gd VO4 La

Incorporated Organic Modified Ag Nanoparticles in Ormocer

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Journal of materials Science & Technology 2004年第4期20卷 477-478页

作者： Haiping XIA, Jianli ZHANG, Jinhao WANG and Qiuhua NIELaboratory of Photo-electronic materials, Ningbo university, Ningbo 315211, China Lab. of Photo-electronic Mat. Ningbo Univ. Ningbo 315211 China

Ag nanoparticles coated trisodium citrate were incorporated in ormocer by sol-gel method. The doping concentration of Ag in ormocer is about 1.0% in weight. The HRTEM demonstrated that the particles disperse in ormoce... 详细信息

关键词： Colloid Ag particle Sol-gel chemistry Ormocer

Crystallization behavior of Ni_(54)Mn_(25.1)Ga_(20.9) ferromagnetic shape memory thin film

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Rare Metals 2007年第S1期26卷 139-142页

作者： MARTIN Saunders Centre for Microscopy and Microanalysis University of Western AustraliaNedlandsW.A.6009Australia

NiMnGaferromagnetic shape memory thin film was deposited onto Al foil using *** sputtering *** crystallization behavior of the film was investigated by XRD and *** activation energy of crystallization of the film was calculated by Kissinger’s *** results show that the crystallization temperature of NiMnGafree-standing thin film in martensite state is 372 ℃,and the activation energy of crystallization is about 191.9 kJ·mol-1.

关键词： Ni-Mn-Ga ferromagnetic shape memory alloys thin films crystallization

Computer simulation on reliability of retention index with FDG-PET and optimization of dual-time-point imaging protocol

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Progress in Natural Science:materials International 2008年第8期18卷 931-937页

作者： Rui Jia a, Jing Bai a,*, Lingfeng Wenb,c, Dagan Fengb,c a Department of Biomedical Engineering, Tsinghua university, Room B209, Building of Medical Science, Beijing 100084, China b School of Information Technologies, university of Sydney, nsw 2006, australia c Department of electronic and Information Engineering, Hong Kong Polytechnic university, Hong Kong Department of Biomedical Engineering Tsinghua University Room B209 Building of Medical Science Beijing 100084 China School of Information Technologies University of Sydney NSW 2006 Australia Department of electronic and Information Engineering Hong Kong Polytechnic University Hong Kong

The inherent noise in positron emission tomography (PET) leads to the instability of quantitative indicators, which may affect the diagnostic accuracy for differentiating malignant and benign lesions in the management of lung cancer. In this paper, the reliability of retention index (RI) is systematically investigated by using computer simulation for the dual-time-point imaging protocol. The area under the receiver operating characteristic (ROC) curve is used to evaluate the optimal protocol. Results demonstrate that the reliability of RI is affected by several factors including noise level, lesion type, and imaging schedule. The RIs with small absolute values suffer from worse reliability than those larger ones. The results of ROC curves show that over delayed second scan cannot help to improve the diagnostic performance further, while an early first scan is expected. The method of optimization based on ROC analysis can be easily extended to comprise as many lesions as possible.

关键词： Reliability Retention index PET (positron emission tomography) Simulation ROC (receiver operating characteristic)

Polar differential power attacks and evaluation

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Science China(Information Sciences) 2012年第7期55卷 1588-1604页

作者： TANG Ming 1 ,QIU ZhenLong 1 ,GAO Si 1,2 ,YI Mu 3 ,LIU ShuBo 1 ,ZHANG HuanGuo 1 & JIN YingZhen 1 1 School of Computer Science,Wuhan university,Wuhan 430072,China 2 State Key Laboratory of Information Security,Institute of Software,Chinese Academy of Sciences,Beijing 100190,China 3 Centre for Computer and Information Security Research School of Computer Science and Software Engineering university of wollongong,wollongong,nsw 2.2.,australia 1. School of Computer Science Wuhan University Wuhan 430072 China2. State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China3. Centre for Computer and Information Security Research School of Computer Science and Software Engineering University of Wollongong Wollongong NSW 2522 Australia

Side channel attacks (SCAs) on security software and hardware have become major concerns on computer and system *** existing SCAs generally require the knowledge of the corresponding cryptographic algorithm and implementation adopted in the target; therefore,they are not fully suitable for practical *** this paper,we propose a novel SCA-polar differential power attack (polar DPA).We found that DPA peaks have different biases for different cryptographic algorithms and *** on these biases,we can successfully attack a block cipher,assuming that the cipher algorithm uses a secret key in its first round,without the knowledge of the cipher algorithm or *** rounds can be treated as a black *** present a detailed theoretical analysis and experiment to demonstrate the correctness and efficiency of our ***,our scheme has demonstrated an improvement over the leakage evaluation scheme due to Ichikawa et al.(CHES 2005).Our evaluation method can be used in electronic design automatic (EDA) flows and can help security circuit designers to understand the data leakage due to SCAs.

关键词： computer security differential power attack side channel attack

Magnetic Properties of Nanometer-Scale NiZnCu Ferrite Thin Films Fabricated by Spray-Spin-Heating-Coating Method

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Journal of materials Science & Technology 2004年第1期20卷 35-37页

作者： Yulan JING, Huaiwu ZHANG, lijun JIA, Yu SHI and Yingli LIUInstitute of Information and materials, university of electronic Science and Technology of China, Chengdu 610054, China Inst. of Info. and Mat. Univ. of Electron. Sci. and Technol. Chengdu 610054 China

A new nanometer-scale ferrite thin film with excellent high-frequency characteristics has been developed by the spray-spin-heating-coating method. The effects of the ion synthesis mechanism, chemical stoichiometry, fabrication method, and doping content on the magnetic properties and microstructure of the thin films have been analyzed. The films formed between 75℃ and 90℃ by spray-spin-heating-coating methods was discovered with fine grain size of about 21 nm, high saturation magnetization (4πMs) of about 6.5 kGs, coercivity of about 9.8 Oe, as well as initial permeability of about 14.0. These films can be widely used in radio-frequency integrated circuit devices.

关键词： Nanometer materials Ferrite thin film Spray-spin-heating-coating

Fullerenol-containing materials Derived by Sol-gel Processing

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Journal of materials Science & Technology 2004年第5期20卷 555-557页

作者： Haiping XIA, Zhaoyang JIANG, Jianli ZHANG, Jinhao WANG, Yuepin ZHANG and Qiuhua NIELaboratory of Photo-electronic materials, Ningbo university, Ningbo 315211, China Lab. of Photo-Electron. Mat. Ningbo Univ. Ningbo 315211 China

Water soluble fullerenols were synthesized and incorporated in SiO2, SiO2-TiO2, GPTMS-SiO2, GPTMS-ATPS inorganic and organic-inorganic materials by sol-gel processes. The maximum concentrations of C60(OH)n and C70(OH)n in the obtained SiO2 gels were estimated to be about 0.6% and 1.5% in weight, respectively. The characteristics of the UV/visible spectra of fullerenols in H2O and various gels were measured and compared. The thermal stability of fullerenols in gels was investigated with differential thermal analysis (DTA). The results indicate that the absorption features of fullerenols in solid gels are similar to those in H2O and the fullerenols in SiO2 are stable at 400℃. The optical limiting effect of the fullerenols was investigated preliminarily.

关键词： Water soluble fullerenol Sol-gel chemistry Thermal stability Optical properties

s-ordering operator expansions of quantum-mechanical fundamental representations and their applications

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Science China(Physics,Mechanics & Astronomy) 2011年第12期54卷 2150-2154页

作者： FAN HongYi 1,3 , XU YeJun 2 & YUAN HongChun 3,4 1 Department of materials Science and Engineering, university of Science and Technology of China, Hefei 230026, China 2 Department of Physics electronic and Engineering, Chizhou university, Chizhou 247000, China 3 Department of Physics, Shanghai Jiao Tong university, Shanghai 200030, China 4 College of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou 213002, China 1. Department of materials Science and Engineering University of Science and Technology of China Hefei 230026 China3. Department of Physics Shanghai Jiao Tong University Shanghai 200030 China2. Department of Physics Electronic and Engineering Chizhou University Chizhou 247000 China4. College of Optoelectronic Engineering Changzhou Institute of Technology Changzhou 213002 China

We show that the quantum-mechanical fundamental representations, say, the coordinate representation, the coherent state representation, the Fan-Klauder entangled state representation can be recast into s-ordering operator expansion, which is elegant in form and has many applications in deriving new operator identities. This demonstrates that Dirac's symbolic method can be merged into Newton-Leibniz integration theory in a broad way.

关键词： s-ordering operator expansion operator identities quantum mechanical representation