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Science china(Technological Sciences) 2010年第1期53卷 242-247页

作者： DONG ZhenWei1,2.WU YaoMing1,MA LiQun2.SHEN XiaoDong2.& WANG LiMin1 1 State Key Laboratory of Rare Earth Resource {3.,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,C hangchun 13.02.,china 2.College of Material Science and {2.,nanjing University of Technology,nanjing 2.0009,china State Key Laboratory of Rare Earth Resource utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China College of Material Science and engineering Nanjing University of Technology Nanjing China

The(La0.67Mg0.3.)1-xTixNi2.75Co0.2.(x = 0,0.05,0.10,0.15 and 0.2.,at%) alloys were synthesized by arc melting and subsequent heat solid-liquid diffusing *** structure,electrochemical properties and kinetic characteristics of the alloys were investigated *** results showed that all the alloys mainly consisted of the(La,Mg)Ni3.LaNi5 phases,and the lattice parameters and the cell volumes of the(La,Mg)Ni3.and LaNi5 phases decreased with increasing Ti *** alloy electrodes could be activated to reach their maximum discharge capacity within five *** cycle life after 100 charge/discharge cycles(C100/Cmax) and the high-rate dischargeability at a discharge current density of 12.0 mA/g first increased and then *** the results showed that low-Ti content in AB3.type hydrogen storage alloys was beneficial to improvements of the overall electrochemical properties,and the optimum overall electrochemical performance of the alloy electrodes was obtained when x = 0.05.

关键词： AB3.type alloy metal hydride electrode microstructure electrochemical property kinetic characteristic

Cross-linked Polyethylenimine as Potential DNA Vector for Gene Delivery with High Efficiency and Low Cytotoxicity

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 780-787页

作者： Wei DONG~(1,2. Guang-Hui JIN~1 Shu-Feng LI~(1,3. Qi-Ming SUN~1 Ding-Yuan MA~1 Zi-Chun HUA~1 1 State Key Laboratory of Pharmaceutical Biotechnology,College of Life Science,nanjing University,nanjing 2.0093.{2. 2.School of Chemical engineering nanjing University of Science and Technology,nanjing 2.0094,{2. 3.College of Basic Medical Science,Southeast University,nanjing 2.0009,{2. State Key Laboratory of Pharmaceutical Biotechnology College of Life Science Nanjing UniversityNanjing 210093 China School of Chemical engineering Nanjing University of Science and TechnologyNanjing 210094 China College of Basic Medical Science Southeast UniversityNanjing 210009 China

Polyethylenimine (PEI) has been known as an efficient gene carrier with the highest cationiccharge *** transfection efficiency of PEI,along with its cytotoxicity,strongly depends on itsmolecular *** enhance its gene delivery efficiency and minimize cytotoxicity,we have synthesizedsmall cross-linked PEI with biodegradable linkages and evaluated their transfection efficiencies in *** study,branched PEI with a molecular weight of 800 Da was cross-linked by small diacrylate[1,4-butanediol diacrylate or ethyleneglycol dimethacrylate (EGDMA)] for 2.6 *** efficiencies of thecross-linked PEI in in vitro transfection of plasmid DNA containing enhanced green fluorescent protein(EGFP) reporter gene were assessed in melanoma B 16F10 cell line and other cell *** cytometrywas used to quantify the cellular entry efficiency of plasmid and the transgene expression *** of the cross-linked PEI in these cells were evaluated by MTT ***-PEI 800-4h,atypical cross-linked PEI reported here,mediated a more efficient expression of reporter gene than thecommercially available 2.-kDa branched PEI control,and resulted in a 9-fold increase in gene deliveryin B16F10 cells and a 16-fold increase in 2.3. cells,while no cytotoxicity was found at the optimizedcondition for gene ***,the transfection activity of polyplexes was preserved in thepresence of serum proteins.

关键词： polyethylenimine gene delivery cytotoxicity B16F10 2.3. cell line

A Hybrid Genetic Algorithm for Reduct of Attributes in Decision System Based on Rough Set Theory

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Wuhan University Journal of Natural Sciences 2002年第3期7卷 285-289页

作者： Dai Jian\|hua 1,2., Li Yuan\|xiang 1,2.,Liu Qun 3.1. State Key Laboratory of Software engineering, Wuhan University, Wuhan 43.072. Hubei,china 2. School of Computer, Wuhan University, Wuhan 43.072. Hubei, china 3. School of Computer Science, Lab. of Software Eng. Wuhan Univ. Wuhan 430072 China Sch. of Comp. Wuhan Univ. Wuhan 430072 China Sch. of Comp. Sci. Chongqing Univ. of Post and Telecom. Chongqing 400065 China

Knowledge reduction is an important issue when dealing with huge amounts of data. And it has been proved that computing the minimal reduct of decision system is NP-complete. By introducing heuristic information into genetic algorithm, we proposed a heuristic genetic algorithm. In the genetic algorithm, we constructed a new operator to maintaining the classification ability. The experiment shows that our algorithm is efficient and effective for minimal reduct, even for the special example that the simple heuristic algorithm can’t get the right result.

关键词： rough set reduction genetic algorithm heuristic algorithm

Performance of iteratively decoded bit-interleaved coded modulation with chaos based interleaving strategies

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Science china(Information Sciences) 2010年第4期53卷 833-841页

作者： ZOU XueLan1*, LIU WeiYan2.& FENG GuangZeng3.1Department of Electronic and Information engineering, Zhejiang Institute of Media and Communications, Hangzhou 3.0018, china 2.epartment of Information engineering, Jiangsu City Vocation College, nanjing 2.003., china 3.ollege of Communication and Information engineering, nanjing University of Posts and Telecommunications, nanjing 2.0003. china Department of Electronic and Information engineering Zhejiang Institute of Media and Communications Hangzhou China Department of Information engineering Jiangsu City Vocation College Nanjing China College of Communication and Information engineering Nanjing University of Posts and Telecommunications Nanjing China

Bit-interleaved coded modulation with iterative decoding (BICM-ID) is a bandwidth efficient trans- mission scheme which is well suitable for next-generation mobile communications. The interleaver design is critical to the high performance of BICM-ID. In this paper we investigate the application of the chaos theory to the interleaver design to further improve the performance of BICM-ID. A new interleaving scheme based on the chaos theory is proposed. Compared with the random interleaver, the proposed approach has the ad- vantages including lower system delay and higher transmission efficiency. Simulation results in both additive white Gaussian noise (AWGN) channel and Rayleigh fading channel are provided, which demonstrates that the new interleaver is better than the random interleaver and exhibits excellent performance when applied to the BICM-ID system.

关键词： chaos interleaving bit-interleaved coded modulation (BICM) iterative decoding

Resolution method for overlapping peaks based on the fractional-order differential

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Science china Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2.& ZHENG Gang2.1 College of Information & Control, nanjing University of Information Science & Technology, nanjing 2.0044, {2. 2.College of Automation engineering, nanjing University of Aeronautics and Astronautics, nanjing 2.0016, {2. College of Information & Control Nanjing University of Information Science & Technology Nanjing China College of Automation engineering Nanjing University of Aeronautics and Astronautics Nanjing China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak

A new method for adaptive color image filtering

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Chinese Science Bulletin 2000年第13期45卷 1230-1235页

作者： JIANG Gangyi, YU Mei & YU Bokang1. Department, of Information & Electronic engineering, Hang/hou University of Commerce, Hangzhou 3.003., china 2. Department, of Electronic engineering, Hangzhou institute of Electronics engineering, Hangzhou 3.003., china 3. State Key Laboratory on Machine Perception, Peking University, Beijing 100871, china Correspondence should be addressed to Yu Mei Department of Information & Electronic engineering Hangzhou University of Commerce Hangzhou China State Key Laboratory on Machine Perception Peking University Beijing China Department of Electronic engineering Hangzhou Institute of Electronics Engineering Hangzhou China

An adaptive color image filter (ACIF) is proposed in this note. Through analyzing noise corruption of color image, efficient locally adaptive filters are chosen for image enhancement. The proposed adaptive color image filter combines advantages of both nonlinear vector filters and linear filters, it attenuates noise and preserves edges and details very well. Experimental results show that the proposed filter performs better than vector median filter, directional-distance filter, directional-magnitude vector filter, adaptive nearest-neighbor filter, and α-trimmed mean filter.

关键词： color image noise analysis locally adaptive filters adaptive color image filter (ACIF).

Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science china Chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2.& YIN Yingwu2.3.1. College of Chemistry & Environment Protection engineering, Southwest University for Nationalities, Chengdu 610041, {3. 2. TH-UNIS Insight Co., Ltd., Beijing 100085, {3. 3. Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, {3. College of Chemistry & Environment Protection engineering Southwest University for Nationalities Chengdu China TH-UNIS Insight Co. Ltd. Beijing China Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 3.%) after 2.h at 2.0℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

Design,analysis and control of hybrid excited doubly salient stator-permanent-magnet motor

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Science china(Technological Sciences) 2010年第1期53卷 188-199页

作者： ZHU XiaoYong1,2.& CHENG Ming1 1 engineering Research Center for Motion Control of MOE,School of Electrical engineering,Southeast University,{2. 2.0096,china 2.School of Electrical and Information engineering,Jiangsu University,Zhenjiang 2.2.13.china engineering Research Center for Motion Control of MOE School of Electrical Engineering Southeast University Nanjing China School of Electrical and Information engineering Jiangsu University Zhenjiang China

In this paper,a new hybrid excited doubly salient stator-permanent-magnet motor is proposed,where both permanent magnets and DC field windings are located in the *** theory,the mathematical model and design method of the motor are *** corresponding output power equation and the relationship between the flux control capability and the extended speed range are deduced in *** using an efficient "one-step" three-dimensional(3.) finite element method,the electromagnetic performances are analyzed,in which the leakage flux outside the stator circumference and end-effect are taken into *** on the operation principle of the motor,the control strategy and scheme are developed and implemented *** experimental results and finite element analysis show that the proposed motor not only maintains the advantages of doubly salient permanent magnet motors,but also offers high energy efficiency over a wide speed range,which makes the motor an interesting candidate for electric vehicles.

关键词： stator permanent magnet motor hybrid excitation doubly salient finite element method flux weakening control

Magnetron sputtering synthesis of large area well-ordered boron nanowire arrays

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Science china(Physics,Mechanics & Astronomy) 2004年第4期47卷 403-415页

作者： CAO Limin1,2. ZHANG Ze2.& WANG Wenkui1,2.1. Key Laboratory of Metastable Materials Science and Technology and College of Materials Science and {3., Yanshan University, Qinhuangdao 066004, china 2. Institute of Physics, Chinese Academy of Sciences, Beijing 100080, china Key Laboratory of Metastable Materials Science and Technology and College of Materials Science and engineering Yanshan University Qinhuangdao China Institute of Physics Chinese Academy of Sciences Beijing China

One-dimensionally nanostructured materials, such as nanowires and nanotubes, are the smallest dimensional structures for efficient transport of electrons and excitons, and are therefore critical building blocks for nanoscale electronic and mechanical devices. In this paper, boron nanowires with uniform diameters from 2. to 80 nm were synthesized by radio-frequency magnetron sputtering of pure boron powder and B2.3.powder mixtures in argon atmosphere. The boron nanowires produced stand vertically on the substrate surface to form well-ordered arrays over large areas with self- organized arrangements without involvement of any template and patterned catalyst. The high-density boron nanowires are parallel to each other and well distributed, forming highly ordered and uniform arrays. A more interesting and unique feature of the boron nanowires is that most of their tips are flat rather than hemispherical in morphologies. Detailed studies on its structure and composition indicate that boron nanowires are amorphous. Boron nanowire appears as a new member in the family of one-dimensional nanostructures. Considering the unique properties of boron-rich solids and other nanostructures, it is reasonable to expect that the boron nanowires will display some exceptional and interesting properties. A vapor-cluster-solid (VCS) mechanism was proposed to explain the growth of boron nanowires based on our experimental observations.

关键词： boron nanowires, magnetron sputtering, arrays, self-assembly.

Preparation of Reactive Powder Concrete Using Fly Ash and Steel Slag Powder

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Journal of Wuhan University of Technology(Materials Science) 2010年第2期25卷 349-354页

作者：彭艳周 College of Hydraulic & Enviormental engineering China Three Gorges University Key Laboratory for Silicate Materials Science and engineering of Ministry of Education Wuhan University of Technology

To decrease the cement and SF content of RPC by using ultra-fine fly ash （UFFA） and steel slag powder （SS）, the effect of these mineral admixtures on compressive strength of RPC were investigated. The experimental results indicate that the utilization of UFFA and SS in RPC is feasible and has prominent mechanical performance. The microstructure analysis （SEM and TG-DTG-DSC） demonstrated that the excellent mechanical properties of RPC containing SS and UFFA were mainly attributed to the sequential hydration filling effect of the compound system.

关键词： ultra-fine fly ash steel slag powder reactive powder concrete sequential hydration microstructure strength