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Progress in natural Science:materials International 2012年第3期22卷 250-257页

作者： Haolong Bai, Xuan Wang, Yitong Zhou, Liping Zhang College of material Science and Technology, Beijing Forestry University, Beijing 100083, China College of material Science and Technology Beijing Forestry University Beijing 100083 China

Poly(vinylidene fluoride) (PVDF) composite membranes blended with nano-crystalline cellulose (NCC) for ultrafiltration were prepared by a Loeb-Sourirajan (L-S) phase inversion process. The effects of NCC concentration on the membrane performances were investigated. Surface chemical compositions, surface and cross-section morphologies, degree of crystallinity and the thermal stability of the membranes were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA) respectively. The mechanical properties of the membranes were also investigated. All the experimental results indicated that the properties of the composite membranes were improved due to the addition of NCC. The pure water flux of composite membranes can reach 230.8 L/(m2 h) and increase up to 47.5% compared with pure PVDF membranes. At the same time, the rejection ratio of a bovine serum albumin solution (1 g/L) was up to 92.5%. The porosity and the mean pore size of the composite membranes were 65% and 49 nm, respectively. Due to the addition of NCC, the degree of crystallinity was increased to 52.1% resulting in the enhanced mechanical properties. A typical asymmetric structure, which was composed of sponge-like dense layer and finger-like microporous support layer, was observed in SEM images of composite membranes.

关键词： Poly(vinylidene fluoride) (PVDF) Nano-crystalline cellulose (NCC) Composite membranes Improved performances

Novel coordination polymers with 1,4-di(benzimidazole-1-yl)benzene modulated by an anion:Syntheses,structures and properties

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Science China Chemistry 2010年第10期53卷 2170-2176页

作者： LI Lei, HU TongLiang, ZENG YongFei, BU XianHe TKL of Metal-and Molecule-Based material Chemistry, Department of Chemistry, Nankai University, Tianjin 300071, China TKL of Metal- and Molecule-Based material Chemistry Department of Chemistry Nankai University Tianjin China

Three novel coordination polymers, {[Co(L)(SO4)(H2O)](CH3OH)}∞ (1), {[Cd(L)2(SiF6)](H2O)}∞ (2) and [Zn(L)(NO3)2]∞ (3), synthesized from 1,4-di(benzimidazole-1-yl)benzene (L), have been characterized by infrared spectroscopy, elemental analysis and single crystal X-ray diffraction. Compounds 1-3 exhibit different structures. Complex 1 has a 3-D diamond network containing 1-D CoII chains connected by SO24- anions; 2 has a 3-D α-Po framework with 1-D porous channels along the c axis; and 3 has a 1-D zig-zag chain structure with a 2-D supramolecular network based on π-π interactions. The magnetic properties of 1 and the solid state fluorescence spectra of 2 and 3 have also been explored.

关键词： anion effect coordination polymer fluorescence magnetic properties structure

Analysis of variance for testing method of cement in determination of strength

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Progress in natural Science:materials International 2011年第4期21卷 341-346页

作者： Hong HUANG,Xiao-dong SHEN State Key Laboratory of materials-Oriented Chemical Engineering,College of material Science and Engineering, Nanjing University of Technology,Nanjing 210009,China State Key Laboratory of materials-Oriented Chemical Engineering College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The statistical tools such as descriptive statistics,full factorial design and analysis of source of variation were used to identify the potential factors that impact the validity of testing method for determining the strength of *** results showed that personal error impacted both accuracy and precision of test *** time associated with temperature fluctuation resulted in strength variation but did not impact the precision of test in all curing *** compactions did not impact the precision of test but resulted in the strength variation on 3 d and 28 d *** methods for the initial moist air curing significantly impacted the precision of testing method and resulted in the strength variation of cement on 1 d.

关键词： testing method of cement analysis of variance strength accuracy precision

Effect of yttrium on the microstructure of a semi-solid A356 Al alloy

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Rare Metals 2008年第5期27卷 536-540页

作者： LIUZheng HU Yongmei Faculty of material and Chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 China

The semi-solid slurry of an A356 Al alloy, which was grain-fined by yttrium, was manufactured by low temperature pouring, The effects of grain-refining on the morphology and the grain size of the primary α phase in the semi-solid A356 Al alloy were researched. The results indicate that the semi-solid A356 AI alloy with particle-like and rosette-like primary α-Al can be prepared by low temperature pouring from a liquid grain-refined A356 alloy. The grain size and particle morphology of primary α-Al in the A356 Al alloy are markedly improved by the addition of 0.5 wt,% Y. The fining mechanism of Y on the morphology and grain size of the primary α-Al in the semi-solid A356 Al alloy was delved.

关键词： A356 Al alloy semi-solid yttrium low temperature pouring

Frequency characteristic of series piezoelectric sensor and application to the determination of water in organic solvents

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Chinese Journal of Chemistry 1994年第1期12卷 58-65页

作者： SHEN, Da-Zhong ZHU, Wen-Hong NIE, Li-Hua YAO, Shou-Zhou New material Research Institute, Hunan University, Changsha, Hunan 410082, China New material Research Institute Hunan University Changsha Hunan 410082 China

Theoretical consideration was proposed for the frequency response of a series piezoelectric sensor to the properties of liquid and verified experimentally. This kind of sensor has sensitive and selective frequency response to the permittivity and specific conductivity of solution with excellent stability, and was applied to the determination of micro-content of water in organic solvents. The detection limit is 0.01 g/L in dioxane.

关键词： Piezoelectric quartz crystal chemical sensor micro-water-content

Preparation and Kinetics of the Thermal Decomposition of Nanosized CuC_2O_4-ZnC_2O_452H_2O

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Wuhan University Journal of natural Sciences 2006年第3期11卷 667-671页

作者： CHEN Donghua HUANG Lianrong TANG Wanjun Hubei Key Laboratory for Catalysis and material Science/College of Chemical and Materal Science South-Central University for Nationalities Wuhan 430074 Hubei China

The physical mixture of nanosized CuC2O4-ZnC2O4·2H2O, as precursors of CuO-ZnO, have been prepared by the one-step solid state reaction method at room temperature. The thermal decomposition processes taking place in the solid state oxalate mixture of nanometer CuC2O4-ZnC2O4·2H2O have been studied in static air using TG, DSC, XRD and TEM techniques. TEM showed that the grain size of the decomposition product is 5-15 nm. The values of the activation energy Eα were determined using the isoconversional procedure of KAS method and the Ozawa method. The most possible mechanism function f（α） of the thermal decompositions of nanosized CuC2O4-ZnC2O4·2H2O are defined using the comparative method, function models of tbe decomposition of CuC2O4 and ZnC2O4, follow tbe same mechanism function ＂Avrami-Erofeev equalion＂. The pre-exponential factor A is obtained on the basis of Eα and f（α）, thus the thermal analysis kinetic triplet of the decompositions of nanosized CuC2O4-ZnC2O4·2H2O are determined.

关键词： nanoparticle copper oxalate zinc oxalate kinetics characterization

Organic solvent-and phase transfer catalyst-free oxidation of cyclohexanol to cyclohexanone with dilute H_2O_2

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Chinese Science Bulletin 2002年第24期47卷 2060-2062页

作者： WEI Junfa, SHI Xianying, HE Diping & ZHANG MinSchool of Chemistry and material Science, Shaanxi Normal University, Xi’an 710062, China School of Chemistry and material Science Shaanxi Normal University Xi'an China

The oxidation of cyclohexanol to cyclohexanone with 30% aqueous hydrogen peroxide by using peroxotung-state complexes formed in situ from sodium tungstate di-hydrate and various bidentate organic ligands as the catalysts, without organic solvents, halide and phase transfer catalyst has been carried out. The influence of 13 ligands on the oxidation is investigated. The maximum yield of cyclohexanone is obtained when using 1,10-phenanthroline (96%) and oxalic acid (95%) as the ligand. Very high yields (around 90%) have also been obtained for the instances of using salicylic acid, 3,5-dibromosalicylic acid, and 8-hydro- xylquino-line as ligands. A research to improve the reaction condition using cheap oxalic acid as the ligand indicates that the optimum condition is that the reaction mixture with a molar ratio of cycohexanol:tungstate dihydrate:oxalic acid: 30% H2O2=100:2:2:120 was stirred at 85-90℃ for 12 h.

关键词： cyclohexanol hydrogen peroxide catalytic oxidation peroxotungstate oxalic acid.

Microstructures and fatigue-free properties of the La^(3+) and Nd^(3+) doped Bi_4Ti_3O_(12) thin films prepared by modified sol-gel technique

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Science China(Technological Sciences) 2008年第11期51卷 1843-1849页

作者： LI MeiYa1,2, PEI Ling1, LIU Jun1, YU BenFang1, GUO DongYun1, SUN XiaoHua3 & ZHAO XingZhong1,2 1 Department of Electronic Science and Technology, School of Physical Science and Technology, Wuhan University, Wuhan 430072, China 2 Key Laboratory of Acoustic and Photonic material and Device of the Ministry of Education, Wuhan Uni- versity, Wuhan 430072, China 3 School of Mechanical and material Engineering, China Three Gorges University, Yichang 443002, China Department of Electronic Science and Technology School of Physical Science and Technology Wuhan University Wuhan China Key Laboratory of Acoustic and Photonic material and Device of the Ministry of Education Wuhan University Wuhan China School of Mechanical and material Engineering China Three Gorges University Yichang China

Ferroelectric Bi3.25La0.75Ti3O12 (BLT) and Bi3.15Nd0.85Ti3O12 (BNT) thin films were fab- ricated on Pt/TiO2/SiO2/Si (100) substrates by a modified sol-gel technique. X-ray diffraction indicated that these films were of single phase with random polycrystal- line orientations. The surface morphologies of the films were observed by scanning electron microscope, showing uniform, dense films with grain size of 50―100 nm. Well-saturated hysteresis loops of the films were obtained in metal-ferroelectric- metal type capacitors with Cu top electrodes at an applied voltage of 400 kV/cm, giving the remanent polarization (2Pr) and coercive field (2Ec) values of the films of 25.1 μC/cm2 and 203 kV/cm for BLT, and 44.2 μC/cm2 and 296 kV/cm for BNT, re- spectively. Moreover, these capacitors did not show fatigue behaviors after up to 1.75×1010 switching cycles at the test frequency of 1 MHz, suggesting a fatigue-free character. The influences of the La3+ and Nd3+ doping on the properties of the films were comparatively discussed.

关键词： bismuth oxides ferroelectrics fatigue sol-gel technique

New compound YZG-330 augments pentobarbital induced sleep behaviors:involvement of Cl-channel activation

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New compound YZG-330 augments pentobarbital induced sleep be...

Segregation of C and P in Steel Droplets Solidified in Drop Tube

中国药理学会第十一次全国学术会议

作者： LIU Li-li,ZHANG Jian-jun (Key Laboratory of Bioactive Substances and Function of natural Medicine,Institute of material Medica, CAMS & PUMC,Beijing 100050,China)

OBJECTIVE Insomnia is an extremely common symptom in modern *** have demonstrated that YZG-330 which is a new modifier of N -(4-hydroxybenzyl) adenine riboside can enhance pentobarbital-induced sleep *** this study, in order to investigate the mechanism of this action,we measured the chloride(Cl ) flux in primary cultured cerebellar granule cells. METHODS Primary cultures of cerebellar cells were prepared from the cerebelli of 7-8-old *** were used for Cl permeability experiments 8 - 10 d after *** used the chloride-sensitive fluorescent probe N-(ethoxycarbonylmethyl)-me-thoxyquinolinium bromide(MQAE) as a tool to estimate the effect of GABA(100μmol·L and 300μmol·L) and YZG-330(10μmol·L and 1μmol·L) on GABA receptor *** we used picrotoxin(100μmol·L and 10μmol·L) to observe whether it can antagonize the effect of YZG-330(10μmol·L and 1μmol·L) on chloride *** The rate of chloride flux for GABA(300μmol·L and 100μmol·L) were increased * to 214%and 181%of control respectively,and the rate of chloride flux for YZG-330(10μmnol·L and 1μmol·L) were increased to 177%and 150%of control ***(100μmol·L) partly blocked YZG-330(1μmol·L)-enhanced chloride flux,and the inhibition rate was 36%.CONCLUSION These data indicate that the effect of chloride flux stimulated by YZG-330 may be mediated by GABA receptor activation.

关键词： insomnia chloride flux GABAA receptor MQAE

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Journal of Iron and Steel Research International 2011年第S1期18卷 282-286页

作者： LI Na,ZHANG Jun-wei,ZHAI Lu-lu (School of material and Metallurgy,University of Science and Technology Liaoning,Anshan,114051,Liaoning,China) Univ Sci & Technol Liaoning Sch Mat & Met Anshan 114051 Liaoning Peoples R China

The properties of steels can be improved by adding appropriate amount of alloying ***,the quality and properties of steels may be affected due to the segregation of the alloying *** solidification was regarded to be an effective method to reduce or eliminate the segregation of alloying *** in this paper,the segregation of C and P was also observed in rapid solidified carbon steel droplets (in silicon oil) by drop tube *** distributions of alloying elements in 0.2m drop tube samples were similar to those in 50m drop tube *** in both 0.2m and 50m drop tube,the segregation of C and P was quite different when the contents of the samples were varied,the segregation profiles were discussed in *** microstructures of 50m droplet samples were a little finer than those of 0.2m droplet *** solidification speed was approximately the same from the surface to the center of each *** high-C samples,the microstructure was also corresponding to the distribution of C.

关键词： segregation C P droplet drop tube