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Enhancement Effect of Gold Nanoparticles on the Bioactivity of Hydrogen-producing Microbe

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Journal of Wuhan university of Technology(Materials Science) 2006年第4期21卷 16-18页

作者：刘光臻 Institute of chemistry Chinese Academy of Sciences Beijing 100080China

In order to increase the yield of hydrogen production for hydrogen-producing microbe, the enhancement effect of nanometer- sized gold panicles on the activity of hydrogen-producing microbe was studied. The yields of hydrogen production in the system added by gold nanoparticles of 6 nm and 12.nm in diameter were obviously increased by about 17% and 9% in contrast to that in blank system. The experimental restdts indicate that gold nanoparticles could significantly enhance the bioactivity of hydrogen-producing microbe.

关键词： gold nanoparticles bioactivity hydrogen-produeing microbe

Degradation of nitrobenzene in wastewater by γ-ray irradiation

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Journal of Environmental Sciences 2004年第3期16卷 364-366页

作者： ZHANG Shu juan 1, FENG Shao hong 1, YU Han qing 1,* , LI Qian rong 2. (1 department of chemistry, {2. of Science & Technology of china, Hefei 2.002., china. 2.Research Center for Physics & chemistry, {2. of Science & Technology of china, Hefei 2.002., china) department of chemistry University of Science & Technology of China Hefei 230026 China.

The degradation of nitrobenzene(NB) by γ ray irradiation was studied. The influences of dose rate and initial NB concentration were investigated in details. At a dose rate of 55 Gy/min, the degradation kinetics was pseudo first order at NB concentrations from 0 2.mmol/L to 4 0 mmol/L. At an initial NB concentration of 0 8 mmol/L, the degradation of NB at various dose rates also followed pseudo first order kinetics. Dissolved oxygen was found to have a positive effect on NB degradation. The degradation products were identified as nitrophenol, nitrosobenzene, and hydroquinone, and so on. Based on the product analysis, possible degradation pathways of nitrobenzene were proposed.

关键词： degradation irradiation nitrobenzene(NB) kinetics

Synthesis and Properties of the Polymeric Surfactant Based on Maleamic Acid and Styrene

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Journal of Wuhan university of Technology(Materials Science) 2011年第1期26卷 79-82页

作者：杨永清 department of Applied chemistry School of Science Northwestern Polytechnical University

An alternative polymeric surfactant P（M3/St） was synthesized by solution polymerization of maleamic acid as hydrophilic monomer and styrene as hydrophobic monomer. Some factors that affect the yield and properties of the polymeric surfactant were investigated systemically. The surface tension of the polymeric surfactant reaches 37-38 mN/m. It is proved that the polymeric surfactant shows very good surface activity and emulsifying ability. The TG analysis shows that the temperature of the thermal degradation can reach 314.4 ℃. It will be used as a new type of polymeric surfactant.

关键词： maleamic acid polymeric surfactant surface activity emulsifying ability thermal resistance

Hardy-Hilbert重级数不等式的推广与改进

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数学的实践与认识 2002年第5期32卷 849-854页

作者：洪勇海南师范学院数学系海南海口571158

本文将著名的 Hardy-Hilbert重级数不等式∑∞m=1 ∑∞n=1ambnm + n≤ πsin(π/p) ∑∞n=1apn1p ∑∞n=1bqn1q∑∞m=1 ∑∞n=1anm + np ≤ πsin(π/p)p∑∞n=1apn进行了带参数形式的推广。

关键词： Hardy-Hilbert重级数不等式 Euler-Maclaurin求和公式权系数

ON THE APPROXIMATELY SIMILARITY OF OPERATORS

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Chinese Annals of Mathematics,Series B 1998年第4期19卷 465-472页

作者： WEI GUOQIANG (department of Mathematics, East china {2. university, Shanghai 2.0062. china.) E china normal Univ Dept Math Shanghai 200062 Peoples R China

The author shows that a rank-preserving *-isorporphism between separable C*-algebras with unity is approximately equivalent to the identity representation. Some applications are made for approximately similarity of n-... 详细信息

关键词： C*-algebra Rank-preserving *-isomorphism Approximately equevalent,Approximately similar n-tuples of operators

Acid-base behavior of cryptand 1, 4, 7, 10, 13, 16, 2., 2.-octaaza-bicyclo [8, 8, 8] hexacosan-3, 8, 12. 17, 2., 2.-hexone and complex formation

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Rare Metals 2002年第1期21卷 12-19页

作者： MO Zunli, CHEN Hong and GAO Jinzhang Institute of chemistry, Northwest normal {2., Lanzhou 730070, china Institute of chemistry Northwest Normal University Lanzhou 730070

The bicyclic cryptand 1,4,7, 10,13,16,2., 2.-octaaza-bigcyclo [8, 8,8] hexacosan-3, 8, 12. 17, 2., 2.-hex-one (COBH) bearing diaminoethane groups along the eight-atom bridges was synthesized. The structure consists of discrete neutral macrobicyclic units; the two cycles share the two tertiary amine nitrogen atoms, which exhibit an endo-cndo conformation. Three identical branches formed by 1, 2.diaminoethane link the two tertiary amine groups. The protonation reactions of cryptand (COBH) and its complex formation with copper (II) were investigated by potentiometry in water and in a DMSO/water (80:2. in mass ratio) mixture as solvents. The cryptand acts as a his-base through its two N-bridgehead and exhibits a strong cooperativity that favors the first protonation and makes the second one difficult (△pK= 5.0). An inward rotation of the amide groups to form hydrogen bonds accounts for this cooperativity. The interaction of COBH with copper (II) leads to several binuclear complex proton contents.

关键词： COBH(cryptand 1,4,7, 10, 13, 16, 2., 2.-octaaza-bigcyclo hexacosan -3, 8, 12. 17,2.,2. - hex-one) macrobicyclic acid-base behavior complex formation proton contents

SINGLE BIRTH PROCESSES

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Chinese Annals of Mathematics,Series B 1999年第1期20卷 77-82页

作者： CHEN MUFA(department of Mathematics,Beijing normal {2.,Beijing 100875,china) Beijing normal Univ Dept Math Beijing 100875 Peoples R China

The single birth process is a Markov chain, either time-continuous or time-discrete, valuedin the non-negative integers: the system jumps with positive rate from k to k + 1 but not tok +j for all j 2.(this explains the meaning of 'single birth') . However, there is no restrictionfor the jumps from k to k - j(1 j< k). This note mainly deals with the uniqueness problemfor the time-continuous processes with an extension: the jumps from k to k + 1 may also beforbidden for at most finite number of k. In both cases (time-continuous or -discrete), thehitting probability and the first moment of the hitting time are also studied

关键词： Markov chains Single birth process Uniqueness criterion

The geodetic numbers of graphs and digraphs

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Science china Mathematics 2007年第8期50卷 1163-1172页

作者： Chang-hong LU~(1,2. 1 department of Mathematics,East china {2. university,Shanghai 2.0062.china 2.Institute of Theoretical Computing,East china Narnal university,Shanghai 2.0062.china 1. department of Mathematics East China Normal University Shanghai 200062 China 2. Institute of Theoretical Computing East China Narnal University Shanghai 200062 China

For every two vertices u and v in a graph G, a u-v geodesic is a shortest path between u and v. Let I(u, v) denote the set of all vertices lying on a u-v geodesic. For a vertex subset S, let I(S) denote the union of all I(u, v) for u, v ∈ S. The geodetic number g(G) of a graph G is the minimum cardinality of a set S with I(S) = V (G). For a digraph D, there is analogous terminology for the geodetic number g(D). The geodetic spectrum of a graph G, denoted by S(G), is the set of geodetic numbers of all orientations of graph G. The lower geodetic number is g ?(G) = minS(G) and the upper geodetic number is g +(G) = maxS(G). The main purpose of this paper is to study the relations among g(G), g ?(G) and g +(G) for connected graphs G. In addition, a sufficient and necessary condition for the equality of g(G) and g(G × K 2. is presented, which improves a result of Chartrand, Harary and Zhang.

关键词： convex set digraph distance geodesic geodetic number 05C12 05C2.

Non-isothermal decomposition kinetics and lifetime of Tb2.0-MBA)6(PHEN)2

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Rare Metals 2003年第3期22卷 155-159页

作者： ZHANGJianjun BAIJihai WANGRuifen WANGShuping LIJibiao ExperimentalCenter NormalUniversityShijiazhuang050016China departmentofComputer HebeiNormalCollegeofScienceandTechnologyChangli066600China departmentofchemistry HebeiNormalUniversityShijiazhuang050091China

The thermal decomposition of Tb_2.O-MBA)_6(PHEN)_2.(O-MBA: o-methylbenzoate;PHEN: 1,10-phenanthroline) and its kinetics were studied under the non-isothermal condition bythermogravimetry-derivative thermogravimetry (TG-DTG) techniques. Kinetic parameters were obtainedfrom analysis of TG-DTG curves by the Achar method and the Madhusudanan-Krishnan-Ninan (MKN) *** most probable mechanism function was suggested by comparing the kinetic parameters. The kineticequation for the first stage can be expressed as dα/dt = Aexp(-E/RT)·3(1 - α)^(2.3). Thelifetime equation at mass loss of 10% was deduced as lnτ= -2..742. + 19797.795/T by isothermalthermogravimetric analysis.

关键词： thermochimica non-isothermal kinetics TG-DTG terbium complex O-methylbenzoate 1,10-phenanthroline