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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, university of science and technology of china, hefei 23.026, china 2. {3. research Laboratory, university of science and technology of china, hefei 23.026, 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.

EFFECT OF BIAS STRESS ON NON-LINEAR INTERNAL FRICTION OF Al-Mg ALLOY

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Acta Metallurgica Sinica(English Letters) 1992年第3期5卷 166-171页

作者： TAN Qi university of science and technology of china,hefei,china Univ of science and technology of China Hefei China

The influence of longitudinal and torsional bias stresses on anomalous amplitude-dependent internal friction was *** longitudinal bias stress may always weaken the anomalous amplitude-dependent effect,while the torsional one may induce different effects from differ- ent directions *** stress effect exhibits only in properly heat treated and cold worked ahoy *** anomalous amplitude-dependent internal friction peaks,P_3.P_2 and P_1, are found to be related closely to slant dislocation kink ***,the application of bias stress to internal friction would be contributed to the study on dislocation structure.

关键词： internal friction bias stress anomalous amplitude effect dislocation kink

Langevin Treatment of Atomic Coherence Effect on Hybrid Erbium doped Fiber Amplification

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Chinese Journal of Lasers 1999年第6期8卷 3-5页

作者： LIU Fangxin 1,3.GUO Yang 2 MING Hai 2 ( 1 structure research Laboratory, 2 Department of Physics, 3.Department of Astronomy and Applied Physics, university of science and technology of china, {3., china) 中国科学技术大学结构研究实验室结构分析开放实验室安徽合肥 230026 中国科学技术大学物理系安徽合肥

The effects of atomic coherence on hybrid erbium doped fiber amplifier (HEDFA) pumped simultaneously by two diode lasers with different frequencies are studied by using Langevin quantum theory. The expressions of coherence and incoherence gain are derived. The theoretical results show that HEDFA has a near flat bandwidth response from 153. to 1568 nm and large coherence gain under the conditions of low temperature and small detuning.

关键词： atomic coherence hybrid erbium doped fiber amplifier LD pump

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, university of science & technology of {3., hefei 23.026, {3.. 2 research Center for Physics & Chemistry, university of science & technology of {3., hefei 23.026, {3.) Department of Chemistry University of Science & Technology of China Hefei 230026 China research Center for Physics & 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

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, university of science and technology of china, hefei 23.026, {3. 2 hefei National Laboratory for Physical sciences at Microscale, School of Life sciences, university of science and technology of china, hefei 23.027, {3. 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

Natural Passivity of Amorphous Fe_(40)Ni_(40)P_(14)B_6 and Fe_(54.6)Ni_(3.)Si_(4.1)B_(2.3.V_1 Alloys

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Journal of Materials science & technology 1994年第1期10卷 75-78页

作者： Erdong LU and Pengshou XU(hefei National Synchrotron Radiation Lab., university of science and technology of china, hefei, {3., china)Mingrong JI Maosheng MA and Xianming LIU(structure research Lab., university of science and technology of china, Hefe Univ of science and technology of China Hefei China

The natural passive films forrned on Fe_(40)Ni_(40)P_(14)B_6 and Fe_(54.6)Ni_(3.)Si_(4.1)B_(2.3.V_1 amorphous alloys long-term exposed in air have been studied by X-ray photoelectron spectroscopy (XPS) and Auger electron (including Ar+ ion depth profiling) spectroscopy (AES). The following aspects have been investigated: (1) chemical states of the elements in the films. binding energies and the chemical shifts measured by XPSf (2) structure and composition of the films fand (3. thickness of the passive films determined by AES depth profiling and XPS analysis.

关键词： Si Natural Passivity of Amorphous Fe V1 Alloys Ni

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 technology, university of science and technology of china, {3., china Department of Modern Physics, university of science and technology of china, {3., china) Department of Electronic science and technology 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.

A multicast routing algorithm with multiple trees

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Journal of Systems Engineering and Electronics 2005年第2期16卷 426-432页

作者： Cui Xunxue 1,2 , Gao Wei3.& Fang Hongyu41. New Star research Institute of Applied technology, hefei 23.03., P. R. {3. 2. Jiangsu Key Laboratory of Computer Information Processing technology,Soochow university, Suzhou 215006, P. R. {3. 3. Department of Electronic Engineering and Information science,university of science and technology of china, hefei 23.027, P. R. {3. 4. School of Electronic science and technology, Anhui university, hefei 23.03., P. R. {3. New Star research Institute of Applied technology Hefei 230031 P. R. China 2. Jiangsu Key Laboratory of Computer Information Processing technology Soochow University Suzhou 215006 P. R. China Department of Electronic Engineering and Information science University of Science and Technology of China Hefei 230027 P. R. China School of Electronic science and technology Anhui University Hefei 230039 P. R. China

Quality of service (QoS) multicast routing has continued to be a very important research topic in the Internet. A method of multicast routing is proposed to simultaneously optimize several parameters based on multiobjective genetic algorithm, after the related work is reviewed. The contribution lies on that the selection process of such routing is treated with multiobjective optimization. Different quality criterions in IP network are taken into account for multicast communications. A set of routing trees is generated to approximate the Pareto front of multicast problem. Multiple trees can be selected from the final set of nondominated solutions, and applied to obtain a good overall link cost and balance traffic distribution according to some simulation results.

关键词： multicast routing quality of service multiobjective optimization genetic algorithms.

Special magnetic phenomena in heavily doped La_(0.7-x)Dy_xSr_(0.3.MnO_3.system

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science china(Physics,Mechanics & Astronomy) 2008年第1期51卷 90-97页

作者： LIU Ning 1,2 ,YAN GuoQing 1,3.,CAI ZhiRang 1 ,PI Li 2 ,ZHANG Bei 2 &TONG Wei 2 1 Department of Physics,Suzhou College,Suzhou 23.000,china 2 structure research Laboratory,{3.,hefei 23.026,china 3.National Laboratory of Solid State Microstructures,Physics Department,Nanjing university,Nanjing 210093.china Department of Physics Suzhou College Suzhou China structure research Laboratory University of Science and Technology of China Hefei China National Laboratory of Solid State Microstructures Physics Department Nanjing University Nanjing China

The magnetism in heavily Dy doped La0.7-xDyxSr0.3.nO3.0.40≤x≤0.70)system is studied in this *** M-T relation seems to be complicated with the increase of *** sample with x=0.40,AFM behavior exists at T≤TN and M-T curves under zero field cooling(ZFC)and field cooling(FC)exhibit typical behavior of spincluster glass state above *** the sample with x=0.50,the M-T curve under ZFC exhibits a valley at a low temperature while the M-T curve under FC exhibits the negative magnetization below *** samples with x=0.60,0.70,their ZFC M-T curves are similar to that of x=0.50,but the FC M-T curves do not exhibit negative values any *** the peculiar phenomena above are well explained by Néel double-lattice model combined with M-H relation at typical *** molecular field theory fits well the negative magnetization for x=0.50.

关键词： heavily doped special magnetic phenomena double-lattice model