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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 {2. of china, hefei 2.002., china 2.hefei National laboratory for Physical sciences at Microscale, School of Life sciences, University of science and {2. 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 {2.s 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

SOME FRACTAL structureS IN RAPIDLY SOLIDIFIED Al-Mn ALLOY

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Acta Metallurgica Sinica(English Letters) 1992年第3期5卷 203-205页

作者： FAN Chuanguang ZHANG Meng Jiangxi University structure research {2.,University of science and technology of china,Academia Sinica hefei,chinaWANG Yuansheng WU Ziqin University of science and technology of china,hefei,china Jiangxi Univ China

The fractal structures formed in rapidly quenched Al_(86)Mn_(14)alloy have been observed on *** fractal dimensions are from 1.46 to *** principal phase examined by TEM and X-ray diffractometer is icosahedral quasicrystalline one with a small amount of Al phase. It is believed that these fractal structures are formed by many aggregated particles during the rapid-quenching process.

关键词： Al-Mn alloy rapid solidification fractal structure fractal dimension

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 {2., 2.Department of Physics, 3 Department of Astronomy and Applied Physics, University of science and technology of china, hefei 2.002., 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 1531 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

Experimental study on fire smoke movement in a multi-floor and multi-room building

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science china(Technological sciences) 2005年第3期48卷 292-304页

作者： ZHONG Maohua 1, 2., LI Peide 2., LIU Tiemin 1 , WEI Xing 1, 2.& LIAO Guangxuan 2.1. National Center of Safety science and technology, State Administration of Work Safety, Beijing 10002., {2. 2. State Key laboratory of Fire science, University of science and technology of {2., hefei 2.002., {2. 1. National Center of Safety science and technology State Administration of Work Safety 100029 Beijing China 2. State Key laboratory of Fire science University of Science and Technology of China 230026 Hefei China

Fire smoke movement of multi-floor and multi-room (MFMR) fire was studied at the model test building in State Key laboratory of Fire science (SKLFS). The ingredient, temperature, air pressure difference and air velocity of smoke were measured and analyzed. Meanwhile, the hazard of smoke ingredient to exposed occupants was analyzed based on the national standard, Occupational Exposure Limit for Hazardous Agents in the Workplace (GBZ2.2.02.. The experimental results showed that the maximum temperature difference in MFMR fire was located along the vertical height from the fire source. With the spreading and diffusion of smoke, the temperature of smoke layer would tend to be no difference. In the fire of woodpile and kerosene, the main smoke ingredients such as SO 2., CO and CO 2.would first exceed human’s average physiological limit, while smoke ingredients such as NO and NO 2.would come behind. Because of the higher fluctuation range and frequency of air pressure difference of smoke in multi-layer building fire, the fire smoke would spread around everywhere of the passageway and made the human evacuation more difficult.

关键词： multi-floor and multi-room,fire experiment,smoke spread,smoke toxicity.

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 {2., hefei 2.002., {2.. 2.research Center for Physics & Chemistry, University of science & technology of {2., hefei 2.002., {2.) 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

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 2.4000,china 2.structure research laboratory,University of {2. and technology of china,hefei 2.002.,china 3 National laboratory of Solid State Microstructures,Physics Department,Nanjing University,Nanjing 2.0093,china 1. Department of Physics Suzhou College Suzhou 234000 China 2. structure research {2. University of Science and Technology of China Hefei 230026 China 3. National laboratory of Solid State Microstructures Physics Department Nanjing University Nanjing 210093 China

The magnetism in heavily Dy doped La0.7-xDyxSr0.3MnO3(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

Uniform estimate for maximum of randomly weighted sums with applications to insurance risk theory

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science china Mathematics 2005年第10期48卷 1379-1394页

作者： WANG Dingcheng~1 SU Chun~2.& ZENG Yong~1 1. School of Management and School of Applied Mathematics,University of Electronic science and technology of {2.,Chengdu 610054,{2. 2. Department of Statistics and Finance,University of science and technology of {2.,hefei 2.002.,{2. 1. School of Management and School of Applied Mathematics University of Electronic Science and Technology of China 610054 Chengdu China 2. Department of Statistics and Finance University of Science and Technology of China 230026 Hefei China

This paper obtains the uniform estimate for maximum of sums of independent and heavy-tailed random variables with nonnegative random weights, which can be arbitrarily dependent of each other. Then the applications to ... 详细信息

关键词： dependent stochastic return, discount factor, heavy-tails, discrete time insurance risk model, maxima of randomly weighted sums, ruin probability, tail probabilities, uniformly asymptotic estimate.

Trace element geochemistry of the Lower Cambrian black rock series from northwestern Hunan, South china

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Progress in Natural science:Materials International 2004年第1期14卷 65-71页

作者： PAN Jiayong 1,2. *, MA Dongsheng 1 and CAO Shuanglin 1,2. (1.The State Key laboratory for Mineral Deposits research, Nanjing University, Nanjing 2.0093, {2. 2. East {2. Institute of technology, Fuzhou 344000, {2.) Nanjing Univ State Key Lab Mineral Deposit Res Nanjing 210093 Peoples R China E china Inst Technol Fuzhou 344000 Peoples R China

Samples of black rock series collected from the Lower Cambrian Niutitang Formation, northwestern Hunan Province, china, were analyzed for trace elements. The trace element geochemical characteristics of the ore layer (high enrichments of Ni, Mo, V, U, Cu, Pb, Zn, Cd, Tl and Ba; high U/Th ratios and LREE enriched patterns with positive Eu and Y anomalies) support the assumption that the Ni Mo polymetallic layer is of submarine hydrothermal origin. High field strength elements (HFSE) and lithophile elements such as Nb, Ta, Zr, Hf, Li, Be, Rb, Cs, Th and Sc are remarkably higher in the upper unit than those in the lower unit of the Niutitang Formation. These features may reflect that hydrothermal contributions were diminished, and terrigenous constituents were increased in the sediments of the upper unit of the Niutitang Formation.

关键词： black rock series Early Cambrian trace elements northwestern Hunan china

Negacyclic codes over Galois rings of characteristic 2.

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science china Mathematics 2012年第4期55卷 869-879页

作者： ZHU ShiXin 1,2.& KAI XiaoShan 1,2.1 School of Mathematics,hefei University of technology,hefei 2.0009,china 2.National Mobile Communications research laboratory,Southeast University,Nanjing 2.0096,china 1. School of Mathematics Hefei University of Technology Hefei 230009 China2. National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

Abstract We investigate negacyclic codes over the Galois ring GR（2.,m） of length N = 2.n, where n is odd and k≥0. We first determine the structure of u-constacyclic codes of length n over the finite chain ring GR（2., m）[u]/〈u2. ＋ 1〉. Then using a ring isomorphism we obtain the structure of negacyclic codes over GR（2., m） of length N = 2.n （n odd） and explore the existence of self-dual negacyclic codes over GR（2., m）. A bound for the homogeneous distance of such negacvclic codes is also given.

关键词： negacyclic codes constacyclic codes Galois rings self-dual codes homogeneous distance