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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei university of science and {2. Beijing,Beijing,china

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

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

γ-Radiation synthesis of nanocrystalline nickel powder from nickel (Ⅱ ) -ammonia complex solution

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Chinese science Bulletin 1997年第8期42卷 644-648页

作者： ZHU Yingjie, QIAN Yitai and ZHANG Manwei1. department of Applied chemistry,{2., hefei 2.002., china 2. Structure Research Laboratory,{2., hefei 2.002., china Departnient of Applied chemistry University of Scirnce and Technology of China Hefei China Structure Research I.aboratory University of Science and Technology of China Hefei China

NANOCRYSTALLINE nickel is very important for its applications in the fields such as catalysis andmagnetic *** usual method used for preparing nanocrystalline nickel is inert gas e-vaporation,which requires high ***,high temperature easily leads tothe growth or oxidation of nickel *** et *** the nickel microaggre-gates dispersed in solution produced by γ-irradiating a dilute solution of Ni2.

关键词： nickel nanocrystalline powder γ-radiation.

Topological chirality and achirality of the closed circular DNAs

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Chinese science Bulletin 1997年第20期42卷 1705-1708页

作者： QIU Wenyuan and XIN Houwen1. department of Chemical Physics, university of science and technology of china, {2. 2.002., china 2. department of chemistry, Lanzhou university, Lanzhou 730000, china Depaitment of Chemical Physics University of Science and Technology of China Hefei 230026 China

THE study of the relations between the topological structure and its function is one of the focus-es in modern chemistry and life science. In this note we set up a topological model to de-scribe the ccDNAs on the basis of Seifert construction in knot theory. Our model for theccDNAs helps to determine whether a structure is topologically chiral or achiral. This is one ofthe fundamental biological problems.

关键词： DNA topology knot theory topologiesl chirality topological achirality.

THE GROWTH THEOREM FOR STARLIKE MAPPINGS ON BOUNDED STARLIKE CIRCULAR DOMAINS

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Chinese Annals of Mathematics,Series B 1998年第4期19卷 401-408页

作者： LIU TAISHUN (department of Mathematics, university of science and technology of china, {2. 2.002., china)REN GUANGBIN (department of Mathematics, university of science and technology of china, {2. 2.002., china) Univ Sci & Technol china Dept Math Anhua 230026 Peoples R China

The authors obtain the growth and covering theorem for the class of normalized biholomorphic starlike mappings on bounded starlike circular *** type of domain discussed is rather general, since the domain must be starlike if there exists a normalized biholomorphic starlike mapping on it. In the unit disc, it is just the famous growth and covering theorem for univalent *** theorem successfully realizes the initial idea of H. Cartan about how to extend geometric function theory from one variable to several complex variables.

关键词： Starlike mappings Growth theorem Starlike circular domains

THE BLOCH CONSTANT OF LOCALLY BIHOLOMORPHIC MAPPINGS ON BOUNDED SYMMETRIC DOMAINS

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Chinese Annals of Mathematics,Series B 1996年第3期17卷 271-278页

作者： GONG SHENG(department of Mathematics, university of science and technology of china, {2. 2.002., china) UNIV SCI & TECHNOL china DEPT MATHHEFEI 230026PEOPLES R CHINA

The estimations of the bounds of the Bloch constant of locally biholomorphic mappingson irreducible bounded symmetric domains are given. When the domain is a unit circle, theestimation of the lower bounds is just the ... 详细信息

关键词： Bounded symmetric domain Bloch mapping Bloch constant,Locally biholomorphic mapping

Epidemic dynamics on complex networks

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Progress in Natural science:Materials International 2006年第5期16卷 452-457页

作者： ZHOU Tao , FU Zhongqian, and WANG Binghong (department of Electronic science and {2., university of science and technology of china, hefei 2.002., china department of Modern Physics, university of science and technology of china, hefei 2.002., china) [a]department of Electronic science and {2. University of Science and Technology of China Hefei China

Recently, motivated by the pioneer work in revealing the small-world effect and scale-free property of various real-life networks, many scientists devote themselves to studying complex networks. One of the ultimate goals is to understand how the topological structures affect the dynamics upon networks. In this paper, we give a brief review on the studies of epidemic dynamics on complex networks, including the description of classical epidemic models, the epidemic spread on small-world and scale-free networks, and network immunization. Finally, perspectives and some interesting problems are proposed.

关键词： epidemic dynamics complex networks critical value immunization small-world effect scale-free property.

Syntheses of amphiphilic biodegradable copolymers of poly(ethyl ethylene phosphate) and poly(3-hydroxybutyrate) for drug delivery

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science china {2. 2009年第7期52卷 961-968页

作者： CHENG Jing1 & WANG Jun2.1 department of Polymer {2. and Engineering, university of science and technology of china, hefei 2.002., china 2.hefei National Laboratory for Physical {2.s at Microscale, School of Life {2.s, university of science and technology of china, hefei 2.002., china department of Polymer science and Engineering University of Science and Technology of China Hefei 230026 China hefei National Laboratory for Physical sciences at Microscale School of Life Sciences University of Science and Technology of China Hefei 230027 China

Biodegradable and amphiphilic triblock copolymers poly(ethyl ethylene phosphate)-poly(3-hydroxybutyrate)-poly(ethyl ethylene phosphate) (PEEP-b-PHB-b-PEEP) have been successfully synthesized through ring-opening polymerization. The structures are confirmed by gel permeation chromatography and NMR analyses. Crystallization investigated by X-ray diffraction reveals that the block copolymer with higher content of poly(ethyl ethylene phosphate) (PEEP) is more amorphous, showing decreased crystallizability. The obtained copolymers self-assemble into biodegradable nanoparticles with a coreshell micellar structure in aqueous solution, verified by the probe-based fluorescence measurements and transmission electronic microscopy (TEM) observation. The hydrophobic poly(3-hydroxybutyrate) (PHB) block serves as the core of the micelles and the micelles are stabilized by the hydrophilic PEEP block. The size and size distribution are related to the compositions of the copolymers. Paclitaxel (PTX) has been encapsulated into the micelles as a model drug and a sustained drug release from the micelles is observed. MTT assay also demonstrates that the block copolymers are biocompatible, rendering these copolymers attractive for drug delivery.

关键词： poly(3-hydroxybutyrate) polyphosphoester drug delivery polymeric nanoparticles

TYPE X MONOTONE SYSTEMS WITH AN ORDER-INCREASING INVARIANT FUNCTION

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Chinese Annals of Mathematics,Series B 1996年第3期17卷 335-342页

作者： JIANG JIFA(department of Mathematics, The university of science and technology of china, {2. 2.0036, china.) department of Mathematics University of Science and Technology of China Hefei 230036 China

The author considers the asymptotic behavior of solutions of a class of ordinary dmerentialequations x = F(x) in the nonnegative orthant R7. Suppose that F(o) = o, Fi(x1,..., xn) isnondecreasing in xk for all k≠ i and that F possesses an order-increasing invarian *** it is shown that every bounded solution to such a system converges to a single equilibrium.

关键词： Type K monotone system Monotone flow Invariant function Equilibrium Convergence

Synthesis and crystal structure of complex of Ce(NO_3)_3 with N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone

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science china {2. 2004年第3期47卷 251-256页

作者： JIANG Yinzhi1,2.& HU Weixiao1 1. department of Pharmaceutical science, Zhejiang {2. of technology, Hangzhou 310032. china 2. department of Applied chemistry, Zhejiang Institute of science and technology, Hangzhou 310033, china 1. department of Pharmaceutical science Zhejiang University of Technology 310032 Hangzhou China 2. department of Applied chemistry Zhejiang Institute of Science and Technology 310033 Hangzhou China

The reaction of 3,6-di-(3-methyl-pyridin-2.yI)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3)3 · 6H2.] generates a new ligand, N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3)2.(H2.)3] · NO3 (III). Crystal data for III: space group P-1, with a = 0.7133(4) nm, b = 1.1139(2. nm, c = 1.4572.3) nm, α= 102.13(2.°, β= 99.81(3)°, γ= 91.10(3)°, Z = 2. V = 1113.6(7) nm3, μ = 2.12. mm?1 and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 10 coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2. molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.

关键词： rare earth, complex, crystal structure, synthesize, 3,6-bis (3-methyl-pyridin-2.yl)-s-tetrazine, N-(3-methyl-pyridin- 2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone.