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Synthesis of spherical Li1.167Ni0.2Co0.1Mn0.533O2 as cathode material for lithium-ion battery via co-precipitation

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Progress in Natural science:Materials International 2012年第2期22卷 126-129页

作者： Xiangqing Liu,Zhimeng Guo Advanced Material&technology institute,University of science and technology Beijing,China Advanced Material & technology institute University of Science and Technology Beijing China

xLi2MnO3(1 x)LiNi0.4Co0.2Mn0.4O2(x=0.5)powders were synthesized from co-precipitated spherical metal carbonate,Ni0.2Co0.1Mn0.533(CO3)*** has been found that the preparation of metal carbonate was significantly dependent on synthetic conditions,including the coprecipitation temperature,kind of precipitator,and stirring *** results of SEM showed that the shape of precursor powders was *** the final product,Li1.167Ni0.2Co0.1Mn0.533O2,was also significantly uniform due to the homogeneity of the metal carbonate precursor,Ni0.2Co0.1Mn0.533(CO3)x,.Li1.167Ni0.2Co0.1Mn0.533O2 has a-NaFeO2 layered structure,as confirmed by XRD *** average particle size was about 10 mm in diameter and the particle size distribution was relatively *** results of XRD and chemical analysis showed that the synthesized Li1.167Ni0.2Co0.1Mn0.533O2 had lower cation mixing and good layered structure,and the chemical composition is almost *** properties during charge and discharge were *** the voltage range of 2.0-4.8 V,the discharge capacity of Li1.167Ni0.2Co0.1Mn0.533O2 was 340 mAh/g.

关键词： Cathode material Co-precipitation Li1.167Ni0.2Co0.1 Mn0.533O2 Lithium-ion battery

A new pseudorandom number generator based on a complex number chaotic equation

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Chinese Physics B 2012年第9期21卷 142-148页

作者：刘杨佟晓筠 School of Computer science and technology Harbin Institute of Technology

In recent years, various chaotic equation based pseudorandom number generators have been proposed. However, the chaotic equations are all defined in the real number field. In this paper, an equation is proposed and proved to be chaotic in the imaginary axis. And a pseudorandom number generator is constructed based on the chaotic equation. The alteration of the definitional domain of the chaotic equation from the real number field to the complex one provides a new approach to the construction of chaotic equations, and a new method to generate pseudorandorn number sequences accordingly. Both theoretical analysis and experimental results show that the sequences generated by the proposed pseudorandom number generator possess many good properties.

关键词： chaotic equation pseudorandom number generator complex number

DETERMINATION　OF　THRESHOLD　PRESSURE　FOR　INFILTRATION　OF　LIQUID　ALUMINIUM　INTO　SHORT　ALUMINA　FIBER　PREFORM

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中国有色金属学会会刊：英文版 1996年第4期6卷 133-137页

作者： Hu Lianxi Luo Shoujing Huo Wencan(School of Materials science and Engineering,Harbin institute of technology,Harbin 150001) School of Materials science and Engineering Harbin Institute of Technology Harbin 150001 China

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关键词： liquid infiltration effective capillary tube radius threshold infiltration pressure metal matrix composite

Influence of Bias on the Properties of Carbon Nitride Films Prepared by Vacuum Cathodic Arc Method

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Journal of Materials science & technology 2004年第6期20卷 735-738页

作者： Zhimin ZHOU, Lifang XIA and Mingren SUNSchool of Materials science and Engineering, Harbin institute of technology, Harbin 150001, China Sch. of Mat. Sci. and Eng. Harbin Inst. of Technol. Harbin 150001 China

Carbon nitride films have been synthesized in a wide range of biases from 0 to -900 V by vacuum cathodic arc method. The N content was about 12.0-22.0 at. pct. Upon increasing the biases from 0 to -100 V, the N content increased from 15.0 to 22.0 at. pct which could be attributed to the knot-on effect. While the further increasing biases led to the gradual falling of the N content to 12.0 at. pct at -900 V due to the enhancement of the sputtering effect. Below -200 V, with the increasing biases the sp2C fraction in the films decreased, as a result of vvhich the I(D)/I(G) fell in the Raman spectra and the sp peaks also showed the decreasing tendency relative to the s peaks in the VBXPS (valence band X-ray photoelectron spectroscopy). While above -200 V, the sp2C fraction increased and the films became graphitinized gradually, accompanying which the I(D)/I(G) rose from -200 V to -300 V and the Raman spectra even shovved the graphite characteristic above -300 V and the sp peaks rose again relative to the s peak. The carbon nitride films mainly consist of three types of bonding: CC, sp2CN and sp3CN bonds. In the first stage the sp3CN relative ratio rises and falls in the second stage, which corresponded well with the variation of the sp2C in the films. The subpiantation mechanism resulting from the effect of ion energy played an important role in deciding'the variation of the microstructure of the carbon nitride films.

关键词： Carbon nitride Vacuum cathodic arc Raman spectroscopy X-ray photoelectron spectroscopy

Feedback image encryption algorithm with compound chaotic stream cipher based on perturbation

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science China(Information sciences) 2010年第1期53卷 191-202页

作者： TONG XiaoJun1 & CUI MingGen2 1School of Computer science and technology, Harbin institute of technology, Weihai 264209, China 2School of science, Harbin institute of technology, Weihai 264209, China School of Computer science and technology Harbin Institute of Technology Weihai China School of science Harbin Institute of Technology Weihai China

In this paper, two new one-dimensional chaotic functions are designed using Devaney chaotic definition. And a dynamically shifting compound chaotic function is constructed based on the two new one-dimensional chaotic functions. The properties of compound chaotic functions are also proved. A new feedback image encryption algorithm is designed using the new compound chaos and an image pixel permutation, 3D baker scheme is described in detail. In the scheme, a new dynamic block dividing the 3D baker is put forward using the compound chaotic map, and the key space expands. In order to produce avalanche effect and sensitivity of cipher to plaintext, the round times are designed to control the cycle. The entropy analysis, difference analysis, weak-key analysis, statistical analysis, cipher random analysis, and cipher sensibility analysis depending on key and plaintext are introduced to test the security of the new scheme of image encryption. The tests show that the image encryption method passes the random tests of NIST FIPS 140-2(2001) and SP 800-22 standards. This paper also solves the problem of short periods and low precision of one-dimensional chaotic function by perturbation.

关键词： compound chaos stream cipher feedback image encryption 3D baker perturbation

Enhanced activity of yqhD oxidoreductase in synthesis of 1,3-propanediol by error-prone PCR

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Progress in Natural science:Materials International 2008年第12期18卷 1519-1524页

作者： Hongmei Li~a Jia Chen~a Yinghua Li~b a institute of Food science and Biological technology,University of Shanghai for science and technology,Shanghai 200093,China b institute of Pharmaceutical Engineering,Zhejiang University,Hangzhou 310027,China institute of Food science and Biological technology University of Shanghai for Science and Technology Shanghai 200093 China institute of Pharmaceutical Engineering Zhejiang University Hangzhou 310027 China

yqhD oxidoreductase was determined to be an NADP-dependent dehydrogenase,and was more active toward 3-HPA when compared to 1,3-propanediol *** further improve enzyme activity towards 3-hydroxypropionaldehyde (3-HPA),error-prone PCR was implemented to mutant yqhD *** mutants,D99QN147H and Q202A with increased catalytic and affinity efficiency,were obtained after one round of error-prone polymerase chain *** the catalytic efficiency of the mutant D99QN147H was up to 4-fold greater than the wild enzyme (0.0375 min-1mM-1vs.0.0078 min-1mM-1).The recombined strain containing pEY28yqhD D99QN147H yielded 28 g L-1of 1,3-propanediol in the fed-batch LB cultures (1 L volume) with an initial 3-HPA concentration of 40 g L-1,which was higher than the 21 and 17 g L-1of 1,3-propanediol from the mutant Q202A and the wild-type,*** for propionaldehyde,the optimal mutant D99QN147H also exhibited higher activity on a range of substituted aldehydes than the wild- type.

关键词： yqhD oxidoreductase Error-prone PCR Catalytic efficiency 1,3-Propanediol

Synthesis and Characterizations of Nanocrystalline WC-Co Composite Powders by a Unique Ball Milling Process

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Journal of Materials science & technology 2004年第1期20卷 7-10页

作者： Jun SHEN, Jianfei SUN and Faming ZHANGSchool of Materials science and Engineering, Harbin institute of technology, Harbin 150001, China Sch. of Mat. Sci. and Eng. Harbin Inst. of Technol. Harbin 150001 China

In order to explore the high efficiency of fabricating nanocrystalline WC-Co composite powders, this paper presented a unique high energy ball milling process with variable rotation rate and repeatious circulation, by which nanocrystalline WC-10Co-0.8VC-0.2Cr3C2 (wt pct) composite powders with mean grain size of 25 nm were prepared in 32 min, and the quantity of the powders for a batch was as much as 800 grams. The as-prepared powders were analyzed and characterized by chemical analysis, X-ray diffraction (XRD), transmission electron microscopy (TEM) and differential thermal analysis (DTA). The results show that high energy ball milling with variable rotation rates and repeatious circulation could be used to produce nanocrystalline WC-Co powder composites with high efficiency. The compositions of the powders meet its specifications with low impurity content. The mean grain size decreases, lattice distortion and system energy increase with increasing the milling time. The morphology of nanocrystalline WC-Co particles displays dominantiy sphere shape and their particle sizes are all lower than 80 nm. The eutectic temperature of the nanocrystalline WC-10Co-0.8VC-0.2Cr3C2 composites is about 1280℃.

关键词： Nanocrystalline material WC-Co composite High energy ball milling

A possible configuration of H_5^+ cluster

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Chinese science Bulletin 2002年第14期47卷 1170-1171页

作者： ZHOU QinianDepartment of Computer Education, Zhejiang institute of science and technology, Hangzhou 310033, China Department of Computer Education Zhejiang Institute of Science and Technology Hangzhou 310033 China

On the basis of our previous work, a configuration of H5+ has been presented that is a square center structure, and the energy for the structure of H5+ has been obtained by IACQM. The result showed that there is an extreme energy Ee: -2.45981 [2 Ry] at R = 2.50a0. It indicates that the square center structure of H5+ system has the certain stability, which is a possible configuration of H5+.

关键词： H5+ IACQM channel energy configuration.

Laser glazing study of Co-based alloy and Ni-Nb-Cr alloy coating

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Chinese Journal of Lasers 1994年第4期B3卷 377-384页

作者： TIAN Nailiang(Department of Applied Physics,Tianjin institute of science and technology, Tianjin 300191,China)YANG Yongqiang(Department of Mechanics, Tianjin institute of Textile science and technology,Tianjin 300160, China) Tianjin Inst of science and Technology Tianjin China

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关键词： Metallic glass cladding layer Co-based