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A whisker-like carbon composite for the immobilization of laccase and its bioelectrochemistry

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science China Chemistry 2010年第6期53卷 1332-1336页

作者： MA GuoXian1,2.ZHONG QingDong2.& LU TianHong3 1department of Chemical engineering,shanghai Institute of Technology,shanghai 2.02.3,China 2.chool of Materials science and engineering,shanghai university,shanghai 2.0072.China 3department of Chemistry,Nanjing Normal university,Nanjing 2.0097,China 1. department of Chemical engineering Shanghai Institute of Technology Shanghai 200233 China2. School of Materials Science and Engineering Shanghai University Shanghai 200072 China3. Department of Chemistry Nanjing Normal University Nanjing 210097 China

A novel mesoporous carbon/whisker-like carbon (MCwc) composite was used for the immobilization of laccase (Lac) and its bioelectrochemical behaviors were *** was confirmed by XPs that Lac was strongly adsorbed on the surface of the MCwc *** cyclic voltammetric results showed that the immobilized Lac underwent a direct quasi-reversible electrochemical *** value of the electron transfer rate constant ks was estimated to be 0.770 s-1,indicating a reasonably fast electron transfer between the immobilized Lac and the underlying *** surface concentration (I-) of Lac was estimated to be 2.730 × 10-12.mol/*** experimental results showed that the immobilized Lac displayed an appreciable electrocatalytic activity to the electrochemical reduction of *** properties could be attributed to the particular structure of loosely packed nanometer-scale carbon whiskers and the existence of a large amount of oxygen-containing *** immo- bilization method and the novel carrier (MCwc) may find new applications in fabricating the biocatalysts for biofuel cells.

关键词： laccase whisker-like carbon composite direct electrochemical reaction oxygen bioelectrochemistry

Ultralight X-type lattice sandwich structure (Ⅱ):Micromechanics modeling and finite element analysis

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science China(Technological sciences) 2009年第9期52卷 2670-2680页

作者： ZHANG QianCheng1,CHEN AiPing 2.CHEN ChangQing2.3 & LU TianJian2.1 state Key Laboratory for mechanical Behavior of Materials,school of Material science and engineering,Xi’an Jiaotong {2.,Xi’an 710049,China 2.MOE Key Laboratory for strength and Vibration,school of Aerospace,Xi’an Jiaotong {2.,Xi’an 710049,China 3 department of engineering Mechanics,AML,Tsinghua {2.,Beijing 100084,China state Key Laboratory for mechanical Behavior of Materials School of Material Science and Engineering Xi’an Jiaotong University Xi’an China MOE Key Laboratory for strength and Vibration School of Aerospace Xi’an Jiaotong University Xi’an China department of engineering Mechanics AML Tsinghua University Beijing China

The methods of homogenization and finite elements are employed to predict the effective elastic constants and stress-strain responses of a new type of lattice structure,the X-structure proposed by the authors in a companion paper. It is shown that in most cases the predictions by the equivalent homogenization theory agree well with the experimental and 3-dimensional finite element calculated results. The theoretical and numerical study supports the argument that the X-structure is superior to the pyramid lattice structure in terms of mechanical strength.

关键词： sandwich panel lattice structure equivalent homogenization finite element model

Y_CΩ_(2.)are easy terms

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Chinese science Bulletin 1998年第20期43卷 1707-1709页

作者： ZHAO Xishun 1 and WANG Ju 2.1. department of Mathematics, Nanjing university, Nanjing 2.0093, China 2. Institute of software, Chinese Academy of sciences, Beijing 100080, China department of Mathematics Nanjing University Nanjing China Institute of software Chinese Academy of Sciences Beijing China

For any natural number n≥1, Y CΩ 2. is an easy term; that is, for any λ term M, λβ+Y\-CΩ 2. =M is consistent, where Y C is Curry fixed point combinator, Ω 2. ≡ω 2. ω 2. and ω 2. ≡λ***...x (there are 2. occurrences of x after λx ). This result is a partial solution to Jacopini’s conjecture: Y CΩ n is an easy term for any natural number n≥2.

关键词： λβ-calculus Kuper’s theorem easy term.

DIMPLE FORMATION ON FRACTURE sURFACE OF sTEEL 55siMnMo

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Acta Metallurgica sinica(English Letters) 1993年第2期6卷 140-143页

作者： LIANG sizu LIANG Yaoneng LIU Zhengyi south China university of Technology,Guangzhou,China Lecturer,department of {2. engineering No.2.south China university of Technology,Guangzhou 510641,China south China Univ of Technology Guangzhou China

The fracture surface of the normalized steel 55siMnMo was observed,under tensile device at- tached on the sEM,to be of ductile dimple feature on the bainite which is composed of lath ferrite and austenite *** dimple is essentially nucleated in the *** the austenitic plastic deformation is remarkable during fracturing,the tear ridge of dimple is very sharp.

关键词： dimple plastic deformation ductile fracture steel 55siMnMo

A Feedback-Based Web search Engine

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Wuhan university Journal of Natural sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2.3 , XU Bao-wen 2.3,4 , ZHOU Xiao-yu 2.3,4 1. department of Computer science and engineering, Nanjing {2. of Posts and Telecommunications, Nanjing 2.0003, Jiangsu, China 2. department of Computer science and engineering, southeast {2., Nanjing 2.0096, Jiangsu, China 3. Jiangsu Institute of software Quality, Nanjing 2.0096 Jiangsu, China 4. The state Key Laboratory of software engineering, Wuhan {2., Wuhan 430072. Hubei, China department of Computer science and engineering Nanjing University of Posts and Telecommunications . Nanjing 210003 Jiangsu China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. Key words WWW - search engine - query reconstruction - feedback CLC number TP 311. 135.4 Foundation item: supported by the National Natural science Fundation of China (60373066). National Grand Fundamental Research 973 Program of China (2.02.B312.0). Opening Foundation of state Key Laboratory of software engineering in Wuhan university, Opening Foundation of Jiangsu Key Laboratory of Computer Information Processing Technology in soochow universityBiography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

A multiphase mesostructure mechanics approach to the study of the fracture-damage behavior of concrete

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science China(Technological sciences) 2008年第S2期51卷 8-24页

作者： TANG XinWei1,ZHANG ChuHan1 & sHI JianJun2.1 state Key Laboratory of Hydroscience and engineering,Tsinghua university,Beijing 100084,China {2. of Urban Construction,Nanhua university,Hengyang 42.001,China 1. state Key Laboratory of Hydroscience and engineering Tsinghua University Beijing 100084 China 2. department of Urban Construction Nanhua University Hengyang 421001 China

A multiphase mesostructure mechanical model is proposed to study the deformation and failure process of concrete considering its heterogeneity at the meso scopic ***,concrete is taken as a type of three-component composite material composed of mortar matrix,aggregates and interfaces on the ***,an efficient approach to the disposition of aggregates of concrete and a state matrix method to generate mesh coordinates for aggregates are ***,based on the nonlinear continuum damage mechanics,a meso-scale finite element model is presented with damage softening stress-strain relationship for describing the mechanical behavior of different components of *** this method,heterogeneities of each component in the concrete are considered by assuming the material properties of three components conform to the Weibull distribution ***,based on this multiphase meso-mechanics model,a simulation analysis of fracture behavior of a rock-fill concrete(RFC) beam is *** study includes experimental tests for determining basic mechanical parameters of three components of RFC and four-point flexural beam tests for verification of the *** is preliminarily shown that the numerical model is applicable to studying failure mechanisms and process of concrete type material.

关键词： concrete multiphase mesostructure mechanics numerical simulation experimental research

On ss-quasinormal subgroups and the structure of finite groups

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science China Mathematics 2011年第3期54卷 449-456页

作者： WEI XianBiao1,2.& GUO XiuYun2. 1department of Mathematics and Physics, Anhui Institute of Architecture and Industry, Hefei 2.002., China 2.0} of Mathematics, shanghai {2., shanghai 2.0444, China 1. department of Mathematics and Physics Anhui Institute of Architecture and Industry Hefei 230022 China2. Department of Mathematics Shanghai University Shanghai 200444 China

A subgroup H of a finite group G is said to be an ss-quasinormal subgroup of G if there is a subgroup B of G such that G = HB and H permutes with every sylow subgroup of B. In this paper, we investigate the structure of a group under the assumption that every subgroup with order pm of a sylow p-subgroup P of G is ss-quasinormal in G for a fixed positive integer m. some interesting results related to the p-nilpotency and supersolvability of a finite group are obtained. For example, we prove that G is p-nilpotent if there is a subgroup D of P with 1 such that every subgroup of P with order |D| or 2.D| whenever p = 2.and |D| = 2.is ss-quasinormal in G, where p is the smallest prime dividing the order of G and P is a sylow p-subgroup of G.

关键词： s-quasinormal subgroups ss-quasinormal subgroups p-nilpotent groups supersolvable groups

Refinement of the crystal structure for a new mineral──antimonselite

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Chinese science Bulletin 1998年第5期43卷 413-416页

作者： MIN Maozhong 1, ZHAI Jianping 1, WANG Xiangyun 1,sHEN Baopei 2. WEN Guangdou 2.and FAN Tao 2.. department of Earth sciences, Nanjing university, Nanjing 2.0093, China 2. Uranium Geology Bureau of Central-south China, Changsha 410000, China department of Earth sciences Nanjing University Nanjing China Uranium Geology Bureau of Central-south China Changsha China

The crystal structure of a new mineral of the stibnite group, sb-2.e-3, has been determined. The cell constants, obtained by least-squares calculation from direct θ -value’s measurements on the diffractometer are: a =1.158 8(5), b =1.174 4(4), c =0.395 5(2. nm; orthorhombic; V =0.538 2. nm+3; Z =4. The space group is Pbnm. X-ray single crystal data, using Mo K α radiation, were measured on a RIGAKU RAsA-5RP automated diffractometer and refined to a final R index of 0.048 1. sb-2.e-3 is isostructural with sb-2.-3 and Bi-2.-3. Each sb(1) atom is six-coordinated by 3 se(1), 1 se(2. and 2.se(3) atoms at distances 0.2.6 0-0.32. 6 nm. Each sb(2. atom is seven-coordinated by 2.se(1), 2.se(2. and 3 se(3) atoms at distances of 0.2.8 1- 0.346 7 nm. The crystal structure consists of chains parallel to c or needle axis. The strongest bonds (shortest separations) are within the chains. Many important physical properties of antimonselite (optical, ferroelectric, etc.) are related to its crystal structure.

关键词： new mineral antimonselite crystal structure.

study on Ceramic Cutting by Plasma Arc

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厦门大学学报（自然科学版） 2002年第S1期41卷 55-56页

作者： XU Wen-ji 1, FANG Jian-cheng 2. LU Yi-shen 1 (1. school of mechanical engineering, Dalian {2. of Technology, Dalian 11602., China 2. College of mechanical engineering and Automation, Huaqiao {2., Quanzhou 362.11, China)

engineering ceramics are typical difficult-to-machine materials because of high hardness and brittleness. PAC (Plasma Arc Cutting) is a very important thermal cutting process and has been successfully used in cutting stainless steel and other difficult-to-machine alloys. PAC’s application in cutting ceramics, however, is still limited because the most ceramics are not good electronic conducts, and transferred plasma arc cannot be produced between cathode and work-piece. so we presented a method of plasma arc cutting engineering ceramics with additional anode. To reduce the kerf width and to improve the kerf quality, the hydro-magnetically confined plasma arc is used to cut engineering ceramic plates. By experiments and analyses the mechanism and characteristics of hydro-magnetic confined plasma are discussed and the effects of secondary confinement on cutting quality, arc properties, and optimal process parameters are presented. When the nozzle diameter is 3 mm, the kerf width of the Al 2. 3 ceramic plate with 6 mm thickness is less than 4.6 mm, and the cutting speed reaches to 0.9～1.2.m/min. Both theoretical analysis and experimental results have proved the feasibility and validity of the newly advanced hydro-magnetic plasma arc cutting, and the following conclusion can be drawn: (1)synthesizing the advantages of both the water-constriction and magnetic constriction, the hydro-magnetic constriction of plasma arc forms a three-dimensional constriction with improved shape and uniformity of arc column, narrower kerfs, minimal beveling of cuts and higher dross-free cutting speeds than those under either water-constriction or magnetic constriction alone.(2.Hydro-magnetic constriction is capable of improving arc stability, which is reflected in the higher arc voltage at which arc-extinction occurs, than that under any single constriction. (3)For a given diameter of nozzle, quality cut can be produced by using a lower arc current than usually required in conventional plas

关键词： plasma cutting engineering ceramic plasma confinement