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Chinese Chemical Letters 2000年第1期11卷 19-20页

作者： Si Jia XUE Jin Shan ZOU Hai Jian YANG (department of chemistry, Central china normal university, Wuhan 430079) Cent china normal Univ Dept Chem Wuhan 430079 Peoples R China

Fifteen N'-(substituted pyrimidin-2-y1)-N-substituted phenoxyacetyl thioureas were synthesized and tested for biological activities. All of them are new compounds and their structures were confirmed by IR. IHNMR. MS and elemental analysis. Some of the target compounds showed excellent inhibitory activities against root and stalk of dicotyledon plant (such as radish). and selective on monoctyledon plant (such as rice).

关键词： 4-Nitrophenoxyacetyl thiourea 2,4-dichlorophenoxyacetyl thiourea synthesis 2-chlorophenoxyacetyl thiourea 2-amino pyrimidine herbicidal activity

A hybrid approach of Knowledge Discovery in fishery resources evaluation

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西南师范大学学报(自然科学版) 1999年第5期 536-544页

作者： Li\ Li department of Computer Science,Southwest china normal university,chongqing 400715

A framework is put for ward,which integrates Knowledge Discovery in Database (KDD) with case based reasoning (CBR) and Bayesian *** following tasks are fulfilled:(1)discovering refined rules;(2)retrieving structured data which can not be described by flat vector feature;(3)forecasting the location of central fishing ground for the next *** these have been applied to a real case with some encouraging and interesting results.

关键词： knowledge discovery in databases bayesian network case based reasoning causal network

The Promoting Effect on the Activities ofFe Doped TiO_2 Photocatalysts

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Chemical Research in Chinese Universities 2001年第2期17卷 187-192页

作者： YU Xi-bin, WANG Gui-hua and LI He-xing (department of chemistry, Shanghai normal university, Shanghai 200234, P. R. china) Shanghai normal Univ Dept Chem Shanghai 200234 Peoples R China

The particles of titanium-iron (Ti/Fe) complex with different Fe contents were prepared by means of the sol-gel method and used as a photocatalyst. The activity of the catalyst was investi- gated as a function of the Fe content during the liquid-phase oxidation of tetracycline, which showed an enhancement at the low Fe content. The XRD, Raman, XPS, and UV-Vis absorp- tion spectra indicated that the crystalline structure of the Ti/Fe complex particles changed from anatase phase to rutile phase when the Fe content increased. The isolated Fe203, Fe304, FeO species were observed and Fe3+ ions were highly dispersed in the TiO2 matrixes, then Ti-O-Fe species were formed. These species increased the surface defects of the Ti/Fe particles. Also, ac- tive hydroxyl radicals could be generated in the catalytic transformation, which led to the higher activity of the catalyst than bare Ti02 for the degradation of tetracycline.

关键词： Titanium Fe doped photocatalyst Photocatalytic activity Tetracycline

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

Solvation effects on brain uptakes of isomers of ^(99m)Tc brain imaging agents

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Chinese Science Bulletin 2002年第21期47卷 1786-1791页

作者： JIA Hongmei, MA Xiaohui, WANG Cunxin & LIU Boli1. department of chemistry, Beijing normal university, Beijing 100875, china 2. Center for Biomedical Engineering, Beijing Polytechnic university, Beijing 100022, china 1. department of chemistry Beijing Normal University Beijing 100875 China 2. Center for Biomedical Engineering Beijing Polytechnic University Beijing 100022 China

Analysis of electrostatic hydration free energies of the isomers of the 99mTc-BAT and 99mTc-DADT complexes is carried out using the computer simulation technique. The results show that not only a correlation exists between the logarithm of the brain uptake and the electrostatic hydration free energy for the isomers of 99mTc-brain radiopharmaceu-ticals, but also a linear relationship exists between the logarithm of the ratio of the brain uptake of the syn isomer to that of the anti one and the difference between the electrostatic hydration free energy of the syn-isomer and that of the anti one. Furthermore, the investigation on the important factors influencing the brain uptakes of 99mTc-radiophar-maceuticals and the reasons of the different biodistribution of the isomers of the 99mTc-complexes is explored at the molecular level. The results may provide a reference for the rational drug design of brain imaging agents.

关键词： 99mTc-brain imaging agent isomer brain uptake electro-static hydration free energy.

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 normal university, Shanghai 200062, 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

EXACT EXPLICIT SOLUTIONS OF THE NONLINEAR SCHRDINGER EQUATION COUPLED TO THE BOUSSINESQ EQUATION

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Acta Mathematica Scientia 2003年第4期23卷 453-460页

作者：姚若侠李志斌 department of Computer Science Weinan Teachers' College Weinan 714000 China department of Computer Science East China Normal University Shanghai 200062 China

A system comprised of the nonlinear Schrodinger equation coupled to the Boussinesq equation (S-B equations) which dealing with the stationary propagation of coupled non-linear upper-hybrid and magnetosonic waves in magnetized plasma is proposed. To examine its solitary wave solutions, a reduced set of ordinary differential equations are considered by a simple traveling wave transformation. It is then shown that several new solutions (either functional or parametrical) can be obtained systematically, in addition to rederiving all known ones by means of our simple and direct algebra method with the help of the computer algebra system Maple.

关键词： Coupled Schrodinger-Boussinesq equations traveling wave transformation Riccati equations solitary wave solution

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 university,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 normal university,Shanghai 200062,china 2 Institute of Theoretical Computing,East china Narnal university,Shanghai 200062,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 05C20

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= -28.7429 + 19797.795/T by isothermalthermogravimetric analysis.

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