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Preparation of PFSA/PSf hollow fiber composite membranes with recovered PFSA for the pervaporation separation of EtOH/H_2.

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science china {2. 2010年第1期53卷 273-280页

作者： LANG WanZhong1,2.TONG Wei2.XU ZhenLiang2.& GUO YaJun1 1Department of chemistry,shanghai Normal {2.,shanghai 2.02.4,china 2.hemical Engineering Research Center,east china {2. of science and technology,shanghai 2.02.7,china 1. Department of chemistry Shanghai Normal University Shanghai 200234 China2. Chemical Engineering Research Center East China University of Science and Technology Shanghai 200237 China

Perfluorosulfonic acid/Polysulfone(PFSA/PSf) hollow fiber composite membranes have been prepared by dip-coating method using PSf ultrafiltration(UF) membrane as substrate with recovered *** composite membranes were applied to the pervaporation separation of 95% ethanol(EtOH)/H2. *** images show that the thickness of the PFSA skin layer of the composite membranes is about 2.μm,much thinner than those of other PFSA composite membranes revealed in the *** of annealing temperature,coating solution concentration and counter-ions of PFSA on the pervaporation performances of the composite membranes were *** total flux decreases and separation factor increases with the increase of annealing *** highest permeation flux of 32.0 g m-2.h-1 and a separation factor of 5.4 is obtained for the composite membrane annealed at 80°*** lowest permeation flux of 396 g m-2.h-1 and a separation factor of 2..7 is obtained for the composite membrane annealed at 160°*** permeation performances of the PFSA/PSf composite membrane are evidently influenced by the counter-ions of *** flux sequence of the PFSA/PSf composite membranes with different counter-ions is H+>Li+>Ca2.>Mg2.>Na+>K+>Ba2.>Fe3+>Al3+,and the separation factor sequence is H+2.2.2.Na+>K+.There are very little variations of △Eapp values between the composite membranes with three divalent counterions(Mg2.,Ca2. and Ba2.),and the △Eapp values of the composite membranes with two trivalent counterions(Fe3+ and Al3+) are relatively high.

关键词： pervaporation hollow fiber composite membrane perfluorslulfonic acid(PFSA) ethanol(EtOH)/H2. mixture

EFFECT OF PAN-MILLING STRESS ON CRYSTAL STRUCTURES OF HIGH DENSITY POLYETHYLENE

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Chinese Journal of Polymer science 2000年第4期18卷 363-367页

作者： Hua Huang Polymer Research Institute, Sichuan university, Chengdu 610065, china {2. of chemistry and Chemical technology,shanghai Jiao Tong university ,shanghai 2.02.0,china Sichuan Univ Polymer Res Inst Chengdu 610065 Peoples R China shanghai Jiao Tong Univ Sch Chem & Chem Technol Shanghai 200240 Peoples R China

A detailed study was performed on the crystal structures of pan-milled high-density polyethylene (HDPE) using differential scanning calorimetry (DSC) and X-ray diffraction. The crystallinity of HDPE first decreased slightly, followed by a gradual increase with increasing milling times. Monoclinic crystals appeared after 4 cycles of milling. With increasing times of milling, the proportion of monoclinic crystals increased significantly while the proportion of orthorhombic crystals decreased gradually. With increasing times of milling, the crystallite size of orthorhombic form decreased greatly, while the size of monoclinic crystallites kept almost constant during milling.

关键词： high-density polyethylene pan-milling crystal structure

Manufacture of the Ultrafine Grain WC/Co Cemented Carbides by Combined Sintering Processing

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 208-213页

作者： Binghai Liu Yue Zhang Shixi Ouyang Qikai Li(Institute of Technical Physics and chemistry, east{2. university of science and technology , shanghai 2.02.7,{2.)(Material science and Engineering school. university of science and technology Beijing, Beijing 100083,{2.)(State Key Laboratory for Synthesis and Processing of Advanced Materials. Wuhan university of science and technology, Wuhan 430070,{2.,) E china Univ Sci & Technol Inst Tech Phys & Chem Shanghai 200237 Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Wuhan Univ Sci & Technol State Key Lab Synth & Proc Adv Mat Wuhan 430070 Peoples R China

A new kind of sintering process, combined sintering process. i.e. vacuum sintering plus hot isolate pressure sintering (HIP), was introduced for producing ultrafine WC-10% Co (mass fraction. so as the follows) cemented carbides. The effects of some processing parameters on the microstructure and mechanical properties of the obtained cemented carbides were studied. The results show that the rapid shrinkage and the pronounced densification of tile cemented carbides took place during the vacuum sintering stage, which is intinaately correlated with the local liquid sintering occurred during this earl} sintering stage for the high surface activity of ultrafine WC-Co powder. The way of high pressure imposing. isothermal treatment cycle during *** sintering and HIP sintering stage directly influence the densitication of compacts and the mechanical properties of the produced WC-10%Co cemented carbides.

关键词： ultrafine WC-Co cemented carbides vacuum sintering HIP sintering

A NOTE ON THE DIPERNA-LIONS FLOWS

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Acta Mathematica Scientia 2011年第5期31卷 1719-1724页

作者：刘昕黄文亮 school of Computer science and {2. Huazhong University of Science and Technology Department of Mathematics East China University of Science and Technology

In this note, we give a short proof for the DiPerna-Lions flows associated to ODEs following the method of Crippa and De Lellis [3]. More precisely, assume that [divb] ∈ Ll∞oc（Rd）, ｜b｜/（1 ＋｜x｜ log ｜x｜） ∈ L∞（Rd） and ｜ b｜ φ（｜ b｜） ∈ Ll1oc（Rd）, where φ（r） = log log（r ＋ c）, c 0. Then, there exists a unique regular Lagrangian flow associated with the ODE X˙（t, x） = b（X（t, x））, X（0, x） = x.

关键词： DiPerna-Lions flow Hardy-Littlewood maximal function

The Preparation and Application of two New Types of Oxazaborolidines

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Chinese Chemical Letters 2000年第5期11卷 381-382页

作者： Guo Bin RONG Xing Ming LI Yong ZHANG (Department of chemistry east{2. university of science and technology. shanghai 2.02.7) E china Univ Sci & Technol Dept Chem Shanghai 200237 Peoples R China

Two new type of 1,3,2.oxazaborolidines were prepared from (Is,2.)-2.amino-1-(4-nitrophenyl)-propane-1-3-diol and were used as catalyst in the asymmetric reduction of acetophenone. The influence of the reaction temperature as well as the effect of the structure of catalyst on the enantioselectivity was investigated. The origin of the products' configuration was discussed.

关键词： oxazaborolidine asymmetric catalytic reduction prochiral ketone

Chemical Extraction Preparation of Delithiated Cathode Materials of Li-ion Battery

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Journal of Wuhan university of technology(Materials {2.) 2009年第6期24卷 863-866页

作者：闫时建 school of Materials science and Engineering Taiyuan University of Science and Technology

A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2.2.8 in water solution, and the solution was stirred continuously to make the chemical reaction proceed sufficiently, then the reaction product was filtered and finally the insoluble delithiated cathode material was obtained. A series of tests were conducted to verify the composition, crystal structure and electrochemical property of the delithiated cathode materials were all desirable. This method overcomes the shortcomings of battery charging preparation and chemical extraction preparation employing other oxidizing agents.

关键词： chemical extraction delithiated cathode material Li-ion battery

Denitrification in tidal flat sediment, Yangtze estuary

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science china {2. 2007年第6期50卷 812-820页

作者： WANG DongQi1,2. CHEN ZhenLou1, XU ShiYuan1, DA LiangJun1, BI ChunJuan1 & WANG Jun1 1 school of Resources and Environment science, {2. china Normal university, shanghai 2.0062. china 2.school of Life science, {2. china Normal university, shanghai 2.0062. china 1. school of Resources and Environment science East China Normal University Shanghai 200062 China 2. school of Life science East China Normal University Shanghai 200062 China

Sediment denitrification rates at six Yangtze River estuary tidal flat locations(mudflats and salt marshes)were measured from July 2.03 to October *** winter and summer,spatial distribution of denitrification rates was not great in the Yangtze estuary,while in spring and autumn,denitrification rates had a great spatial distribution because of the human activity *** temporal change of denitrification rates was *** ranged from 0.2.to 36.4 umolN·m^(-2.·h^(-1),and were higher in the *** annual average of sediment denitrification rate was 18.2.12.3 mu molN · m^(-2.· h^(-1)in the middle tidal flat and 15.1 ±9.45 mu molN·m^(-2.·h^(-1)in the low tidal flat in the Yangtze *** analysis indicated that the temperature was the primary factor controlling the process of denitrification(significant positive correlation,P<0.01);at the same time,the content of sediment total nitrogen(TN)and the molar ratio of sediment carbon and nitrogen(C/N)had significant positive correlation(P<0.05)and negative correlation(P<0.05)with denitrification rates,*** the Yangtze estuary,increasing of water salinity had no significant inhibition of denitrification because of the wide change range of water salinity.

关键词： Yangtze estuary, tidal flat sediment, denitrification, effect factors

A simple solution route to control synthesis of Fe_3O_4 nanomaterials at low temperature and their magnetic properties

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science china {2. 2009年第7期52卷 916-923页

作者： LIU Yi1,2. CHEN Yun1, ZENG YuPing2.& WANG ShiLong3 1 Department of chemistry and Chemical Engineering, Zaozhuang university, Zaozhuang 2.7160,{2. 2.shanghai Institute of Ceramics, Chinese Academy of sciences, shanghai 2.0050,{2. 3 school of Life science and technology, Tongji university, shanghai 2.0092.{2. 1. Department of chemistry and Chemical Engineering Zaozhuang University Zaozhuang 277160 China 2. shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China 3. school of Life science and {2. Tongji University Shanghai 200092 China

A series of nanostructured iron compounds including cubic Fe3O4 and orthorhombic FeOOH were synthesized via a facile low temperature (in the range of 60-100℃) solution method. In the whole process, the interaction between FeCl2.4H2. and methenamine (C6H12.4) was carried out through a reflux device under different reaction conditions such as temperature, solvent, and duration. The samples were detected by XRD, TEM, SAED, physical property measurement system, and Mssbauer spectroscopy, separately. The experiments showed that magnetic mixture nanoparticles had flake and rod morphologies, and cubic Fe3O4 took on grain nanostructure. Magnetism measurements indicated that the saturated magnetization of the as-obtained magnetic mixture was lower than that of the cubic magnetite. Mssbauer spectroscopy testified the sample consisting of cubic magnetite rather than γ-Fe2.3. In addition, a possible growth mechanism of cubic magnetic nanoparticles under different conditions was discussed.

关键词： magnetic nanoparticles cubic Fe3O4 oxidation-coprecipitation method reflux magnetic properties at room temperature Mssbauer spectrum

Effect of Excipients on Stability and Structure of rhCuZn-SOD Encapsulated in PLGA Microspheres

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Chemical Research in Chinese Universities 2004年第3期20卷 323-327页

作者： LIU Ling 1,2.,GE Yu 1 and YUAN Qin-sheng 1 1. State Key Laboratory of Bioreactor Engineering and Institute of Biochemistry,east{2. university of science and technology,shanghai 2.02.7,P. R.{2. 2. Public Health school,Nanjing Medical university,Nanjing 2.002.,P. R.{2. E china Univ Sci & Technol State Key Lab Bioreactor Engn Shanghai 200237 Peoples R China E china Univ Sci & Technol Inst Biochem Shanghai 200237 Peoples R China Nanjing Med Univ Sch Publ Hlth Nanjing 210029 Peoples R China

When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic solvent and a polymer may cause the denaturation of the protein. In this study,we investigated the enzymatic activity change and the effect of the excipients on the stability of recombinant human Cu,Zn-superoxide dismutase(rhCu,Zn-SOD) during the emulsification. The specific activity recovery was found to be concentration dependent and the excipients involved such as PEG 600 and Tween 2.,and trehalose were shown to increase the stability of rhCu,Zn-SOD. The protein structural integrity within the microspheres was analyzed by FTIR. The structure of rhCu,Zn-SOD within PLGA microspheres containing trehalose was found to be similar to that of the native solid state,whereas the protein encapsulated during the preparation in the absence of any excipient changed due to the possible hydrophobic interaction with the polymer. The results suggest that a rational stability strategy for protein to be encapsulated into microspheres should aim at different processes.

关键词： Poly( DL -lactide-co-glycolide)(PLGA) microsphere Recombinant human Cu Zn-superoxide dismutase(rhCu Zn-SOD) Fourier transform infrared(FTIR) spectroscopy Protein stability Excipient