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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 Technology of china, hefei 2.002., china 2.hefei national laboratory for physical sciences at microscale, school of life sciences, 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 {2. 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

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Short exposure to paclitaxel induces multipolar spindle formation and aneuploidy through promotion of acentrosomal pole assembly

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science china({2. sciences) 2010年第11期53卷 1322-1329页

作者： BIAN MingLei1, FU JingYan1, YAN Yan1, CHEN Qiang1, YANG Chao2. SHI QingHua2.JIANG Qing1 & ZHANG ChuanMao1 1MOE Key laboratory of Cell Proliferation and Differentiation and the State Key laboratory of Bio-membrane and Membrane Bio-engineering, College of life sciences, Peking university, Beijing 100871, china 2.7} national laboratory for physical sciences at {12. and school of life sciences, university of science and Technology of china, hefei 2.002., china 1. MOE Key laboratory of Cell Proliferation and Differentiation and the State Key laboratory of Bio-membrane and Membrane Bio-engineering College of Life Sciences Peking University Beijing 100871 China2. Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences University of Science and Technology of China Hefei 230026 China

Paclitaxel is a widely used microtubule drug and cancer medicine. Here we report that by short exposure to paclitaxel at a low dose, multipolar spindles were induced in mitotic cells without centrosome amplification. Both TPX2.depletion and Aurora-A overexpression antagonized the multipolarity. Live cell imaging showed that some paclitaxel-treated cells accomplished multipolar cell division and a portion of the daughter cells went on to the next round of mitosis. The surviving cells grew into clones with varied genome content. The results indicated that an aneuploidy population could be induced by short exposure to paclitaxel at a low dose, implicating potential side effects of paclitaxel.

关键词： paclitaxel tpx2 Aurora-A multipolar cell division aneuploidy

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Facile synthesis of dendrimer-like star-branched poly(isopropylacrylamide) via combination of click chemistry and atom transfer radical polymerization

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science china Chemistry 2010年第12期53卷 2520-2527页

作者： WAN XueJuan,XU Jian & LIU ShiYong CAS Key laboratory of Soft Matter Chemistry Department of Polymer science and Engineering,{2. national laboratory for physical sciences at the microscale,university of science and Technology of china,{2. {12.,china 1. CAS Key laboratory of Soft Matter Chemistry Department of Polymer science and Engineering Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Hefei 230026 China

We report a facile synthesis method of dendrimer-like star-branched poly(N-isopropylacrylamide) (PNIPAM) via the combination of click chemistry and atom transfer radical polymerization (ATRP) by employing the arm-first ***,the α-azido-ω-chloro-heterodifunctionalized building block,N3-PNIPAM-Cl (G0-Cl),was synthesized via ATRP by 3-azidopropyl 2.chloropropionate as the *** advantage of click chemistry,the first generation (G1) of dendrimer-like star-branched PNIPAM,G1-(Cl)3,was facilely prepared via the click coupling reaction between G0-Cl and *** the construction of second generation (G2. dendrimer-like star-branched PNIPAM,G2.(Cl)6,terminal chloride moieties of G1-(Cl)3 were first converted to azide,and then reacted with excess tripropargylamine to give G1-(alkynyl)6 ;G2.(Cl)6 was subsequently prepared via click reaction between G1-(alkynyl) 6 and *** permeation chromatography (GPC) and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry were employed to confirm the successful construction of dendrimer-like star-branched *** unique thermal phase transition behavior of this dendrimer-like star-branched polymer in aqueous solutions was further investigated by turbidimetry and micro-differential scanning calorimetry (Micro-DSC).

关键词： dendrimer-like branched ATRP click chemistry

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Porous Y_2._3 microcubes:synthesis and characterization

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Rare Metals 2011年第6期30卷 577-582页

作者： DENG Bin DING Liwen CHEN Jianjun ZHONG Shengliang Department of Chemistry and life sciences Xiangnan University Chenzhou 423000 China College of Chemistry and Chemical Engineering Jiangxi Normal University Nanchang 330022 China Division of Nanomaterials and Chemistry Hefei National Laboratory for Physical Sciences at Microscale University of Science and Technology of China Hefei 230026 China

In this work, a facile route using a simple solvothermal reaction and sequential heat treatment process to prepare porous Y2.3 microcubes is presented. The as-synthesized products were characterized by X-ray powder diffraction （XRD）, scanning electronic microscope （SEM）, energy dispersive spectrometer （EDS）, thermogravimetric analysis （TG）, and differential thermal analysis （DTA）. The thermal decomposition process of the Y2.3 precursor was investigated. SEM results demonstrated that the as-prepared porous Y2.3 microcubes were with an average width of about 2. μm and thickness of about 8μm. It was found that the morphology of the Y2.3 precursor could be readily tuned by varying the molar ratio of S2.2. to y3＋. Y2.3：Eu3＋（6.6%） microcubes were also prepared and their photoluminescence properties were investigated.

关键词： yttrium oxide yttrium sulfate solvothermal synthesis porous material

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Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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science china Earth {2. 2005年第10期48卷 1672-1677页

作者： YANG Gang1,2. DU Andao1, LU Jiren3, QU Wenjun1 & CHEN Jiangfeng2.1. national Research Center of Geoanalysis, Beijing 100037, china 2. {2. for Earth Material Cycling, school of Earth and Space sciences, university of science and Technology of china, hefei 2.002., china 3. Institute of Mineral Resource, Chinese Academy of Geological sciences, Beijing 100037, china national Research Center of Geoanalysis Beijing china laboratory for Earth Material Cycling School of Earth and Space Sciences University of Science and Technology of China Hefei China Institute of Mineral Resource Chinese Academy of Geological sciences Beijing china

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 833 ± 35 Ma, initial 187Os/188Os ratio of 0.2.9 ± 0.018 (MSWD = 1.7) and γOs = 130 ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 82. ± 8 Ma (n=5, MSWD = 4.3). The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

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

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science china(Technological {2.) 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 {2. 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.

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Re-Os isotopic system and formation age of subcontinental lithosphere mantle

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Chinese science Bulletin 2000年第3期45卷 193-200页

作者： ZHI XiachenDepartment of Earth and Space sciences, university of {2. and Technology of china, hefei 2.002., china Advance Research Center for Earth {2. and Astronomy, USTC, Third World Academy of {2., hefei 2.002., china laboratory of Chemical Geodynamics, USTC, hefei 2.002., china Department of Earth and Space sciences University of Science and Technology of China Hefei China Advance Research Center for Earth science and Astronomy USTC Third World Academy of Science Hefei China laboratory of Chemical Geodynamics USTC Hefei China

The determination of the formation age of subcontinental Lithosphere Mantle (SCLM) is a widely concerned issue in mantle geochemistry. it is difficult to obtain the formation age of SCLM using lithophile isotopic systems such as Rb-Sr, Sm-Nd, U-Th-Pb, ete., but as siderophile elements, the Re-Os isotopic system provides a powerful tool for that work. Here a comprehensive review on the recent development in Re-Os dating for SCLM has been given.

关键词： Re-Os isotopic dating subcontinental lithospheric mantle mantle derived peridotites Re depleted model age whole rock isochronological age.

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Statistical study on the relationship between halo CME and coronal dimming

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science china(Technological {2.) 2010年第7期53卷 2020-2024页

作者： LIU Kai1, XIA LiDong2. CHEN Yao2.& SONG HongQiang2.1 school of Earth and Space sciences, {2. of science and Technology of china, hefei 2.002., china 2.Shandong Provincial Key laboratory of Optical Astronomy and Solar-Terrestrial Environment, school of Space science and Physics, Shandong {2. at Weihai, Weihai 2.42.9, china 1. school of Earth and Space sciences University of Science and Technology of China Hefei 230026 China2. Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and Physics Shandong University at Weihai Weihai 264209 China

The data from SOHO/EIT and SOHO/LASCO observations are used to determine the relationship between coronal dimming and full halo CME (coronal mass ejection). The events of full halo CME examined in this study were observed by LASCO co-ronagraphs and taken from the CD AW CME catalog from 1996 to 2.08. Dimming events are identified by using difference images taken by EIT at the 195 A passband. We found strong relationship between full halo CMEs and the coronal dimming events, with up to 93.3% of the front-side halo CMEs associated with the EIT 195 A dimming events. Full halo CMEs that show no clear signatures of dimming usually have lower sky plane velocities (<700 km/s) compared to the mean velocity of CMEs associated with dimming.

关键词： Sun coronal mass ejection coronal dimming extreme-ultraviolet

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Sm-Nd and zircon SHRIMP U-Pb dating of Huilanshan mafic granulite in the Dabie Mountains and its zircon trace element geochemistry

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science china Earth {2. 2005年第12期48卷 2081-2091页

作者： HOU Zhenhui1, LI Shuguang1, CHEN Nengsong2. LI Qiuli1 & LIU Xiaoming3 1. school of Earth and Space sciences, {2. of science and Technology of china, hefei 2.002., china 2. The Key laboratory of Continental Dynamics of the Ministry of Education, Northwest {2., Xi’an 710069, china 3. Faculty of Earth sciences, china {2. of Geosciences, Wuhan 430074, china 1. school of Earth and Space sciences University of Science and Technology of China 230026 Hefei China 2. The Key laboratory of Continental Dynamics of the Ministry of Education Northwest University 710069 Xi’an China 3. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China

The mafic granulites from Huilanshan are outcropped on the center of the Luotian dome in the northern Dabie Mountains. The Sm-Nd isochron defined by granulite-facies meta-morphic minerals (garnet + clinopyroxene + hypersthene) yields an age of 136 ± 18 Ma indicating the early Cretaceous granulite-facies metamorphism. The cathodoluminescence (CL) images of zircons from the granulite show clearly core-mantle-rim structures. The zircon cores are charac-terized by typical oscillatory zoning and highly HREE enriched patterns, which suggests their magma origin. Some zircon cores among them with little Pb loss give SHRIMP U-Pb ages rang-ing from 753 to 780 Ma, which suggests that the protolith of Huilanshan granulite is Neopro-terozoic mafic rocks. The zircon mantles usually cut across the oscillatory zone of the zircon cores have 3―10 times lower REE, Th, U, Y, Nb and Ta contents than the igneous zircon cores but have high common Pb contents. These characteristics suggest that they were formed by hydrothermal alteration of the igneous zircons. The part of zircon mantles with little Pb loss give a similar SHRIMP U-Pb age (716―780 Ma) to the igneous zircon cores, which implies that the hydrothermal events occurred closely to the magmatic emplacement. In view of the strong early Cretaceous magmatism in the Luotian dome, consequently, the Huilanshan mafic granulite was formed by heating of the Neoproterozoic mafic rocks in mid-low crust, which caused the granu-lite-facies metamorphism underneath the Dabie Mountains. The similarity between the granulite metamorphic age (136 ± 18 Ma) defined by Sm-Nd isochron and K-Ar age of 12.―12. Ma given by amphible from the gneiss in Luotian dome suggests a rapid uplifting of the Luotian dome, which may result in further exhumation of the ultrahigh pressure metamorphic rocks in the Dabie Mountains.

关键词： Dabie orogen, granulite, zircon U-Pb ages, Sm-Nd age.

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Study on transmittance spectra of ITO thin films by ellipsometric method

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science china(Technological {2.) 2010年第7期53卷 1893-1896页

作者： SUN ZhaoQi1, CAO ChunBin12., CAI Qi1 & SONG XuePing1 1 school of Physics and Material science, Anhui {2., hefei 2.0039, china 2.school of sciences, Anhui Agricultural {2., hefei 2.0036, china 3 Key laboratory of Opto-electronic Information Acquisition and Manipulation, Ministry of Education, hefei 2.0036, china 1. school of Physics and Material science Anhui University Hefei 230039 China2. School of Sciences Anhui Agricultural University Hefei 230036 China3. Key Laboratory of Opto-electronic Information Acquisition and Manipulation Ministry of Education Hefei 230036 China

ITO films with thicknesses (134+8) nm, grown on glass substrates by sputtering method, were post-annealed at the temperatures of 100, 2.0, 300 and 400°C for 1 h, respectively. The as-deposited ITO film was amorphous, but crystallized with annealing at elevated temperatures, as demonstrated by X-ray diffraction. The transmittance spectra of all samples were obtained and subsequently simulated by means of spectroscopic ellipsometry. The optical constants n and k of the films were extracted. With the annealing temperature increasing, the optical constants n and k of the films firstly decreased then increased in the whole investigated wavelength range. The optical band gaps of all films were evaluated and they varied between 3.74 and 3.93 eV.

关键词： ITO films optical constants transmittance spectra spectroscopic ellipsometry analysis

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