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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., china) 中国科学技术大学数学系安徽合肥

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) department of Electronic science and {2. University of Science and Technology of China Hefei 230026 China department of Modern Physics University of Science and Technology of China Hefei 230026 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.

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

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

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science china Chemistry 2009年第7期52卷 961-968页

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

REACTION MECHANISM OF BENZOPHENONE-PHOTOINITIATED CROSSLINKING OF POLYETHYLENE

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Chinese Journal of Polymer science 2002年第4期20卷 291-307页

作者： Bao-jun Qu State Key Laboratory of Fire science and department of Polymer science and Engineering university of science and technology of china hefei 2.002. china university of science and {2. of china State Key Laboratory of Fire Science and Department of Polymer Science and Engineering Hefei 230026

The radical intermediates, the crosslink microstructures, and the reaction mechanism of benzophenone (BP)-photoinitiated crosslinking of low-density polyethylene (LDPE) and model compounds (MD) have been reviewed in detail. The spin-trapping electron spin resonance (ESR) spectra obtained from the LDPE/BP systems with spin-trap agents show that two kinds of polymer radical intermediates are mainly formed: tertiary carbon and secondary carbon radicals. The spin-trapping ESR studies of MD/BP systems give further evidence that photocrosslinking reactions of PE predominantly take place a sites of tertiary carbon, secondary carbon, and especially allylic carbon when available. The high resolution C-13-NMR spectra obtained from LDPE and MD systems show that the crosslink microstructures have H- and Y-type links and that their concentrations are of the same order. The fluorescence, ESR, C-13 and H-1-NMR spectra from the PE and MD systems demonstrate that the main photoreduction product of BP (PPB) is benzpinacol formed by the recombination of two diphenylhydroxymethyl (K-.) radical intermediates. Two new PPB products: an isomer of benzpinacol with quinoid structure, 1-phenylhydroxymethylene-4-diphenylhydroxymethyl-2.5-cyclobexadiene and three kinds of alpha-alkyl-benzhydrols have been detected and identified. These results provide new experimental evidence for elucidating the reaction mechanism in the BP-photoinitiated crosslinking of polyethylene.

关键词： photocrosslinking mechanism polymer radical intermediates crosslink microstructures photolytic products of benzophenone polyethylene model compound

SYNTHESIS AND CHARACTERIZATION OF FOUR-ARMED BLOCK POLY(STYRENE-b-p-NITROPHENYL METHACRYLATE)PREPARED BY THE ATRP METHOD

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Chinese Journal of Polymer science 2002年第4期20卷 353-360页

作者： Cai-yuan Pan Lei Tao Ye Liu department of Polymer science and Engineering{2., hefei 2.002. china department of Polymer science and Engineering University of Science and Technology of China Hefei 230026

A novel tetrafunctional initiator, C [CH_2. (CH_2._3 OOCCH(Br)CH_3]_4 (1), was synthesized through the reaction oftetraol with α-bromopropionyl chloride, and then was used as initiator of atom transfer radical polymerization (ATRP) in thepreparation of 4-armed polystyrene (PSt) with narrow polydispersity. The structure, molecular weight and molecular weightdistribution (MWD) of each arm were studied by ~1H-NMR and GPC data of hydrolyzed products of the 4-armed PSt. TheATRP of St using 1/CuBr/bpy as initiator system is of 'living' character based on the following evidence: narrow MWD,constant concentration of chain radical during the polymerization, control of molecular weight by the molar ratio of monomerconsumed to 1. The 4-armed poly(St-b-p-nitrophenyl methacrylate) [poly(St-b-NPMA)] was prepared by the ATRP ofNPMA using 4-armed PSt with terminal bromine as the initiator, and characterized by FT-IR, ~1H-NMR spectra and GPCcurves. The micelles with PSt as core, and PNPMA as shell were formed by dropping DMSO into a solution of 4-armedpoly(St-b-NPMA) in DMF, as proved by laser light scatter (LLS) method.

关键词： Tetrafunctional initiator Atom transfer radical polymerization 4-Armed polystyrene 4-Armed poly(styrene-b-pnitrophenyl methacrylate) Unimolecular micelles

Chinese Jingdezhen blue and white imperial porcelain

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science china(Technological sciences) 2004年第3期47卷 366-375页

作者： WU Juan1, LI Jiazhi1, DENG Zequn1 & WANG Changsui2.1. Laboratory of Ancient Ceramics, Shanghai Institute of Ceramics, Chinese Academy of sciences, Shanghai 2.0050, china {2., university of science and technology of china, hefei 2.002., china Laboratory of Ancient Ceramics Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China department of history of {2. and archaeometry University of Science and Technology of China Hefei 230026 China

Jingdezhen blue and white imperial porcelain specimens from the Yuan, Ming and Qing dynasties have been systematically analyzed using a nondestructive test method—— energy dispersive X-ray fluorescence analysis (EDXRF). The derived data of major and trace element compositions have been treated by correspondence analysis. The variation laws of the composition patterns for Jingdezhen blue and white imperial porcelain in different historical periods owing to the change in raw materials, recipe and technology have been discussed, and a time model related to variation of element composition has been preliminarily established, It would be helpful for scientific dating of Jingdezhen blue and white imperial porcelain, and even for the studies on the whole field of identification of ancient ceramics.

关键词： energy dispersive X-ray fluorescence analysis, blue and white imperial porcelain, correspondence analysis.

An experimental study on the self-adaption mechanism used by evolutionary programming

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Progress in Natural science:Materials International 2008年第4期18卷 481-486页

作者： Jingsong He a,b, a department of Electronic science and {2., university of science and technology of china, hefei 2.002., china b Nature Inspired Computation and Application Laboratory, university of science and technology of china, hefei 2.002., china department of Electronic science and {2. University of Science and Technology of China Hefei 230027 China Nature Inspired Computation and Application Laboratory University of Science and Technology of China Hefei 230027 China

Evolutionary programming (EP) is one of the most important methods for numerical optimization. Its main technique is the combi- nation of mutations and the self-adaption mechanism. In the past years, studies on EP focused on how to improve the effciency of muta- tions with different probability distributions, and few of them touched on the question that the self-adaption mechanism did not work sometimes, but simply followed the original suggestion. So far, no experimental results have shown why this is a question. This paper firstly gives a primary analysis on the behavior of the self-adaption mechanism, and then presents experimental evidences to show why its adaptive ability is doubtful.

关键词： Evolutionary programming Cauchy mutation Self-adaption mechanism

The feasibility analysis of the application of TPV system in reentry

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science china(Technological sciences) 2010年第12期53卷 3310-3315页

作者： YE Hong & GENG Xue department of Thermal science and Energy Engineering,{2., hefei 2.002., china department of Thermal science and Energy Engineering University of Science and Technology of China Hefei China

A fundamental design of using thermophotovoltaic (TPV) system to convert the huge aerodynamic heat into electricity during the reentry process was described. The influences of heat conducting way, spectral filter and selective radiating surface on the system performance were analyzed in detail. The results showed that as a thermal conducting component, SiC is better than ablation material, with more electricity output but a larger cooling load, and that the adoption of spectral filter and selective radiating surface could lower the power output to some extent, yet diminish the cooling load prominently.

关键词： TPV reentry process spectral filter selective radiating surface