25 June 2011, Volume 42 Issue 06
    

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    综述
  • . 2011, 42(06): 1-0.
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    Abstract: In present, mechanical alloy (MA) has become extremely promising technology regarding synthesizing hydrogen storage alloy. The technology can improve effectively property of alloy, however the grinding time, balling atmosphere, ball-to-powder and so on affect the misrostructure and hydrogen storage performance of alloy to varying degrees. This paper summarizes mainly research conclusions at home and abroad, providing reference for further investigating hydrogen storage alloy by adjusting these factor.
  • 研究与开发
  • YUAN Jin-Hai
    . 2011, 42(06): 3-0.
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    The modification of sodium bentonite with EDTA by microwave were studied, based on the removal rate of Pb2+ as the reference index. The best modification conditions: bentonite 3g, EDTA 1g, pH value to 8 ,microwave power 500W, reaction temperature 35 ℃, microwave reaction 5min;Optimum adsorption conditions: adjust pH value to 5.83, adding 0.4 g bentonite, oscillation temperature 30 ℃, batch adsorption 40 minutes. The results showed that the Pb2+ removal rate may reach to 94% using the modified bentonite as adsorbent, the saturated adsorption weight is 29. 67mg/g.the max adsorption ability of modified bentonite is twice sodium bentonite in weight. XRD shown that the dimension of the pillared interlayer was increased from 1.51nm to 1.65nm,IR spectrum certified that appeared C-C adsorb peak, element analysis result shown that the organ C,N,H increased than the bentonite.
  • 综述
  • Zhen-Jiang LIBing-Yu FAN;
    . 2011, 42(06): 4-0.
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    In this paper, based on the recent research achievements of our group,the latest preparation research progress of SiC one-dimensional and quasi-one-dimensional nanomaterials are reviewed. The technological process advantages of chemical vapor deposition method, melts growth method, carbothermal reduction method and sol-gel method are mainly introduced, and the morphology, outstanding properties and applications of SiC one-dimensional and quasi-one-dimensional nanomaterials obtained by the different preparation methods are briefly summarized. The faced problems and the development trends of the synthesis technology of SiC one-dimensional and quasi-one-dimensional nanomaterials are summarized.
  • 研究与开发
  • Yun Lu
    . 2011, 42(06): 5-0.
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    Abstract: CdTe/PEDOT-PSS microspheres are fabricated by in-situ seed polymerization. The morphology, structure, optical absorption and emission properties are characterized by using SEM FT-IR, XPS, Uv-vis and fluorescent spectra. The results suggest that the CdTe/ PEDOT-PSS hybrids synthesized by seed polymerization exhibit uniform microsphere structure. The absorption spectrum for hybrids is the sum of the spectra of two components, and the peak at 550nm in emission spectrum is a result of charge transfer, which indicates the potential application of the microspheres optoelectronic and photovoltaic devices.
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    . 2011, 42(06): 6-0.
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    OTS as stencil,BiFeO3 films were successfully prepared on ITO/glass substrates by Liquid Phase Self-assembled Method using Bi(NO3)3?5H2O,Fe(NO3)3?9H2O as raw materials and citrate acid as chelating agent.The influence of pH values of precursor solutions on BiFeO3 films was studied.The BiFeO3 films prepared under different pH values were characterized by XRD,EDS and SEM.The results indicated that:the nucleated rates of the chelates of Bi3+ are larger than that of the Fe3+, the pure phase BiFeO3 films could not obtained until the Fe3+/Bi3+ molar ratio was added to 2.6 when the pH value is 1.5;as the increase of the pH value, pure phase BiFeO3 films could not obtained until adjusting the Fe3+/Bi3+ molar ratio in precursor solutions;the proper pH values for the process are in the range of 1.50~1.65,the BiFeO3 films prepared in the range are all dense,grown well,the sizes of grains were well-distributed and increased with the pH values.
  • Xian-Lei SONG;Zhan-Bo SUN
    . 2011, 42(06): 8-0.
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    Al80-XSi20MnX (X=0,5,7,10mol%) ribbons were prepared by melt spinning. The phase constitutions, thermodynamic state,microstructures and electrochemical performances have been measured. The results reveal that when Mn contents are in a range of 5%-7%, only a supersaturated solid solution of Si and Mn in fcc-Al and some metallic glass can be detected. The specific capacities is similar with that of Al60-XSi40MnX (X =0, 5, 7, 10, mol%), but higher than Al70-XSi30MnX (X =0, 5, 7, 10, mol%). It is considered that Li atoms are mainly stored in the Al-Si-Mn supersaturated solid solution, when Si and Mn contents are in a range of 20%-40%, 5%-7%, respectively. The grain boundaries and phase boundaries have a significant contribution for Li storage. The cycle ability of the alloys is relevant to the compositions. Mn additions can promote more atoms to dissolve in the Al-based supersaturated solid solution, resulting in an improvement of the cycle performance by an effect on the diffusion of Li atoms.
  • LIU Heng Quan;
    . 2011, 42(06): 9-0.
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    The newly developed biliary stent should have good mechanical properties, as well as excellent biocompatibility in order to meet the needs of reducing immunological reaction in vivo. In this work, Ti-O film was deposited on 316L stainless steel (316L SS) by unbalanced magnetron sputtering device, and the structure of Ti-O film was characterized by X-ray diffraction (XRD). The interaction of Ti-O film and bile was also investigated by incubating in human fresh bile. The results showed that the surface of Ti-O film could reduce bacteria adherence and form bacterial biofilm owing to more surface energy. The mesobilirubin reducing and the change of the stability of bile are other factors of evaluating biocompatibility. It’s important to develop new biliary stent materials based on its biocompatibility.
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    . 2011, 42(06): 10-0.
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    The aim of the present study is to investigate the mechanism of interactions between gold nanoparticles (GNPs) and human dermal fibroblasts-fetal (HDF-f) based on proteomics technology combining bioinformatics analysis. 20 nm GNPs was prepared by sodium citrate reducing chloroauric acid at first. Then Methylthiazoltetrazolium (MTT) assay and flow cytomtery were applied to evaluate cytotoxicity and the influence on cell cycle and apoptosis by GNPs. Finally, differentially expressed proteins in HDF-f treated with GNPs were obtained using proteomics technology and bioinformatics tool was employed to carry out the Gene Ontology (GO) analysis. MTT assay showed that 200μM 20nm GNPs caused no cytotoxicity to cells after treated for 1, 4 and 8h. Flow cytometry experiment results suggested the effects of GNPs on cells were mainly on S and G2/M phase. 29 proteins were identified with different expression in all three-culture periods using proteomics technology. GO analysis of 29 differentially expressed proteins indicated that GNPs may have an influence on the HDF-f through impacting the transcription processes of RNA, cholesterol and cellular energy metabolism, as well as inducing immune cell responses.
  • ;;;;
    . 2011, 42(06): 11-0.
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    Lithium iron (Ⅱ) phosphate & lithium vanadium phosphate mixing materials (LFVP) were prepared by “Physical blending method” and “chemical blending method”, and the obtained materials were characterized by crystal structure, carbon analysis, grain size distribution, morphology and conductivity. We found in the process of “physical blending method”, the strong mechanical force impacted the material’s crystal structures and the carbon coating on the surface of the materials; A few materials grains may also agglomerate. The good crystal structural material synthesized by “chemical blending method” has more excellent electrochemical performance, its discharge capacity is 194.5mA.h.g-1 and 85 mA.h.g-1 at 0.1C and 20C respectively; When the material was discharged at 1C for 1000 times, the capacity also remained 120 mA.h.g-1, so it has important practical value. All of the excellent electrochemical performances can be attributed to its fine and uniformly distributed materials grains, carbon-coating, and the trace impurities. Therefore “chemical blending method” is the preferred method to prepare LFVP.
  • Zi-Qiang XU ;;
    . 2011, 42(06): 12-0.
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    Using LTCC dielectric/ferrite composite material is the key and the research focus of manufacturing compact multilayer chip EMI filters. The co-fireability of different materials can be achieved and modified by adulteration and optimizing tape casting process, adjustment the materials sintering ability and using the sandwich structure. Results show that the filter with center frequency 85 MHz (3 dB) and attenuation≥30 dB (at 250~2500 MHz), arrives designed goal. The form dimensions are 1.61 mm×0.79 mm×0.81 mm, much less than the conventional filters.
  • . 2011, 42(06): 13-0.
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    Hydroxyapatite/polyamide-6 (HA/PA6) composite scaffolds were prepared using injection-molding technique,and analyzed by SEM,XRD,DSC and mechanical testing. The results demonstrate that this process can effectively control the mechanical properties, porosity and pore size of HA/PA6 composite scaffolds by changing the HA content, the content of azodicarbonamide (AC) and shot size. The obtained HA/PA6 scaffolds with a pore size ranging from 100~500 μm and a porosity more than 65% can possess both the demanded porous structure and mechanical performance, and the compressive modulus and strength of the fabricated HA/PA6 scaffolds are similar to or higher than those of trabecular bone and close to those of the cancellous bone. Compared with common methods to fabricate scaffolds, this process makes the fabrication of composite scaffolds in a rapid and convenient manner.
  • ;;;;
    . 2011, 42(06): 14-0.
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    Abstract:The porous anodic aluminum oxide was prepared on the high-purity aluminium foil through direct curret anodizing.While scanning electron microscope was used to observe the surface topography and thickness of the oxide. Cyclic voltammetry and eletrochmical impedance spectrum were used to characterize the capacity of the AAO. The results revealed that AAO consist of parallel nanopore canals with the pore diameter of 60 to 80nm,which were perpendicular to the surface,the thickness of the porous layer was about 20 ?m; The specific capacitance of the porous anodic aluminum oxide was about 5μF/cm2,and could be applied at voltages between 200V and 250V;The results indicated that the porous anodic aluminum oxide had a good future on the application of the medium and high voltage aluminum electrolytic capacitor.
  • ;Qing-Ju LIU
    . 2011, 42(06): 15-0.
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    The crystal structures,electronic structures and optical properties of Platinum-doped anatase TiO2 were calculated by first-principles with plane-wave ultrasoft pseudopotential approach. The calculated results show that the lattice is distorted, the crystal cell volume and the octahedral dipole moments are increased;the impurity level both at the valence band top and the conduction band bottom are formed by Pt 5d orbit level with O 2p and Ti 3d orbit level hybridization which resulted in the energy gap narrowed and the red-shift of the light absorption wavelength. The theoretical calculation results are consistent with that of the experiment study reported, and give a good mechanism interpretation to the photocatalytic activity enhancement Pt-doped anatase TiO2.
  • Zhen LIU
    . 2011, 42(06): 16-0.
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    Polyvinylidene fluorid(PVDF) microporous membranes were prepared via thermally induced phase separation (TIPS) process with the mixed diluents of Dimethyl phthalate(DMP) and dioctyl phthalate (DOP). The effects of polymer concentration,cooling rate,ratio of mixed diluents and coagulation bath temperature on the membrane micrographs were investigated. The experimental results showed that microporous membrane morphologies were transited from branch structure to spherulite, and finally changed to compact structure with the polymer concentration increased. The crystalline grain size decreased and the amount of crystalline grain increased with the cooling rate increased. The microporous membrane spherulite was changed perfect with DBP’s weight ratio of mixed diluents increased. As coagulation bath temperature increased, the microporous membrane spherulite decreased and lace structure increased, the smooth and pore sizes uniform of membrane increased.
  • Yi-Shan LIUPei-Pei GUO;;;
    . 2011, 42(06): 17-0.
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    Abstract: Using skin collagen fiber (CF) as raw material, Schiff base structure contained CF (Sa-CF) was synthesized through CF-salicylaldehyde reaction, then metal ions, including Fe3+, Mn2+, Co2+, Cu2+and Zn2+ were doped in Sa-CF to make M-Sa-CF radar waves absorbents. Sa-CF and M-Sa-CF were pressed and membranes were obtained. The probe method was used to determine conductivity of Sa-CF and M-Sa-CF membranes, and the arch measurement method was used to investigate their radar waves reflectance loss (RL) in the frequency range of 0.5~18.0 GHz. Experimental results indicated that the conductivity of CF was significantly increased three orders of magnitude after reacted with salicylaldehyde, and further increased after doping with metal ions. It was found that the conductivity of Zn2+ doped Sa-CF was 8.37×10-4 S?cm-1. The electric-loss is the radar waves absorption mechanism of Sa-CF and M-Sa-CF . The conductivity of Sa-CF is increased after doped with metal ions, and therefore their absorbing strength are also increased. However, the radar waves reflectance loss (RL) of M-Sa-CF is quite different when doped with different metal ions. The greatest RL of Fe-Sa-CF was 14.68 dB at 8.29 GHz, while Cu-Sa-CF was only 8.35 dB at 8.29 GHz. It was found that the RL and frequency bandwidth of M-Sa-CF were greatly enhanced and widened respectively when doped with Fe3+, Mn2+ and Zn2+, which have the electronic configuration of half-full-shell and full-full-shell. With different dosage of doping, the greatest RL and its frequency location were also changed.
  • ;
    . 2011, 42(06): 18-0.
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    Abstract: In order to improve the electrochemical cycle stability of La-Mg-Ni system (A2B7-type) hydrogen storage alloy, the Si is slightly added in the alloy, La0.75Mg0.25Ni3.3Co0.2Six(x=0, 0.05, 0.1, 0.15, 0.2) hydrogen storage alloys were prepared by casting. The electrochemical performances and microstructures of the alloys were determined and measured, at the same time the kinetic performances of the as-cast were measured, including the HRD, the EIS and so on. The obtained results show that the alloys are multi-phase structure and are composed of the CaCu5-type phase and the Ce2Ni7-type phase. The amount of the CaCu5-type phase gradually increases with the increase of Si content, but the amount of the Ce2Ni7-type phase correspondingly decrease. The addition of Si enhances the cycle stability of the alloys, but decreases the discharge capacities and the HRD of the alloys, this is relate to the add of Si change the relative content of the phase in the alloys and make the passivation phenomenon.
  • Guang-Shun HUANG;Gang Zhang
    . 2011, 42(06): 19-0.
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    A novel polyarylene sulfide ketone amide (PASKA) was synthesized with 4,4’-thiodibenzoyl chloride (TDC) and 4,4’-(4-amino phenyl sulfide) diphenyl ketone (BAPK) through low temperature solution polycondensation. Their structures were confirmed by FT-IR spectrum, 1H-NMR spectrum and elemental analysis, meanwhile some other properties of PASKA were investigated, such as thermal property, aggregation structure and solubility. The intrinsic viscosity of the polymers was 0.77dl/g obtained with optimum synthesis conditions. The polymers were found to have excellent thermal performance with glass transition temperature (Tg) of 239.9oC, initial degradation temperature (Td) of 439oC. At the same time they showed improved solubility in polar aprotic solvents. They could afford flexible and better membranes with water-flux 24.1-0.6L/m2.h.
  • . 2011, 42(06): 20-0.
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    Field emission arrays (FEAs) were fabricated by magnetron sputtering, photolithography, wet etching technique and electrophoretic deposition. The CNTs cathodes were characterized by the optical microscopy, field emission scanning electron microscopy (FESEM) and Raman spectra. And then, its field emission characteristics based on planar-gate triode with CNTs emitters were also investigated. The optical microscopy and field emission scanning electron microscopy (FESEM) image indicates that the cathode electrodes and gate electrodes were interdigitated and paralleled on the same plane and CNTs emitters were selectively defined on the cathode in this triode structure. Its field emission performance shows that the turn-on voltage of planar-gate triod field emission cathode with CNTs emitters was about 155V and the emission current came to 286μA. The field emission properties were completely modulated by gate voltage. In addition, field emission properties of EPD CNTs and scrren printed CNTs cathode were compared. The results indicate that the EPD CNTs cathode has lower turn-on voltage and higer luminescence uniformity than that of the screen printed CNTs cathode.
  • ;
    . 2011, 42(06): 21-0.
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    The carbon fibre reinforced pantograph sliding plates were fabricated by heated pressing, with modified phenolic resin as bonder, the continuous carbon fibre / short fibre is a reinforcing phase, the copper is electric conductive phase and graphite is lubricating phase. The impact toughness, electric resistance and wear resistance of the slide plate were tested. Wear surface and impact fracture were examined by scanning electron microscope (SEM). The results show that the continuous carbon fibre reinforced pantograph sliding plate has superior impact toughness and wear resistance than that of short carbon fibre reinforced one. Mechanical properties are largely affected by carbon fibre fraction. The interface bond between fibre and resin is good. In addition, adhesion wear, abrasive wear and oxidation wear are the main wear form of pantograph slide plates.
  • ; ;;
    . 2011, 42(06): 22-0.
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    The multilayer composite films consisting of K7[CuBW11O39] with Keggin structure and G4 poly(amidoamine)(PAMAM) dendrimer were fabricated on the ITO electrodes by layer-by-layer self-assembly technique. The obtained films were characterized by X-ray photoelectron spectroscopy (XPS), UV-Vis and atomic force microscopy (AFM). It was shown that the incorporation of [CuBW11O39]7- and PAMAM were alternately assembled into multilayer uniform films. The nanopaticles consisting of [CuBW11O39]7- assembled on PAMAM were homogeneous in size and highly dispersed. These particles size were 30-45 nm in diameter and 25-45 nm in height. Cyclic voltammetry showed that the multilayer films were stable and exhibited good catalytic activities for the reduction of nitrite in acidic aqueous solution.
  • ;Jing-Pei LIU ;;;;
    . 2011, 42(06): 23-0.
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    This paper aims to obtain amino-modified magnetic nano-rods as drug-carriers, for further coupling with biological molecules to prepare magnetic biological dual target nano-drugs. Magnetic FeO(OH) nanorods were prepared by method of partial oxidation. Based on maintaining the original morphologies, the products were coated by silica and modified by amino group for synthesizing nano-drugs carriers. The crystal morphology, structure, magnetism and surface group of products are characterized by TEM (SAED), XRD, VSM and FTIR, respectively. The results show that the size of orthorhombic FeO(OH) nanorods with soft magnetism is between 30 nm and 70 nm, and average aspect ratio is ~ 37. Thickness of silica-coated FeO(OH) nanorods is ~ 45 nm. After FeO(OH) nanorods were coated with silica gel, the saturation magnetization and residual magnetization are decreased, except for no obvious change of the coercivity. The infrared absorption bands of -NH2 appeared around 3380~3200cm-1 and 1650 cm-1~1510 cm-1 demonstrate the amino group on the surface of the products.
  • QUAN Guo zheng ;;;;
    . 2011, 42(06): 24-0.
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    The true stress-strain curves of as-cast AZ80 magnesium alloy were achieved by a series of isothermal compression tests, which would be taken as the basic data for characterizing the evolution of dynamic recrystallization (DRX). In order to obtain the activation energy of DRX and some other essential parameters, the conventional hyperbolic sine equation was adopted and solved by regression analysis. Based on the analysis of work hardening plots before and after the peak points of stress-strain curves, three potential key points were identified as following: the critical strain for DRX initiation, the strain for peak stress and the strain for maximum softening rate, which contributes to characterizing DRX evolution. The modified Avrami type equation representing the evolution of DRX volume fraction was adopted, and a dimensionless intermediate parameter, , was further introduced to couple the effect of deformation temperature, strain rate, strain and DRX volume fraction. Result shows that DRX volume fraction increases gradually until a constant value of 100%. At a constant strain rate, the strain corresponding to the same DRX volume fraction increases with decreasing deformation temperature.
  • ;Yi-ding SHEN
    . 2011, 42(06): 25-0.
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    Styrene Acrylic Emulision was prepared from styrene,butyl-acrylate, N-methylolacrylamide and acrylamide using polyvinyl alcohol as dispersing agent. Water-dispersible Polyisocyanate was obtained from HDI trimer and MPEG500. Styrene Acrylic Emulision was Crosslinked by Water-dispersible Polyisocyanate. The particle size and size distribution, apparent viscosity of modified emulsion, water resistance and mechanical properties of membrane from the emulsion were studied. By means of FT-IR and TGA,the structure, composition and p roperties of the copolymer were characterized. The result indicated that the particle size and size distribution become larger and broader, the apparent viscosity increased with the dosage of the crosslinking agent increased, the mechanical properties and water resistance significantly increased because of the incorporation of water -dispersible Polyisocyanate.
  • ;Li Hongtao
    . 2011, 42(06): 26-0.
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    Mg alloy substrate samples were cleaned at different plasma cleaning process and pure Cr coatings were deposited using closed field unbalanced magnetron sputter ion plating technique. Surface micrographs of Mg alloy substrate and adhesion strength of the coatings were analyzed by SEM and scratch tester. The results show that:The role of excessive cleaning voltage in the surface of substrate make the deep-hole diameter is greater than 0.5-like structural defects and after long time cleaning the energy accumulation effect generated the temperature increase significantly and the local region of the melting, sintering phenomenon by the ion bombardment of the substrate surface are the essential reasons of the adhesion strength of following accumulated Coatings is low.
  • . 2011, 42(06): 27-0.
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    The 5,10,15,20-tetraphenylporphyrin indium(InTPP) molecule was aggregated to be nano-material in the water/dimethylsulfoxide mixed solution by self assembly approach. We investigated the optimum temperature was 50 degrees centigrade. The structure and surface morphology of the nano-InTPP were characterized by field emission scanning electron microscopy (FE-SEM). The optical properties of nano-InTPP were characterized by UV-visible spectrometer. The FE-SEM results showed the morphology of nano-InTPP was rodlike, the size of nano-InTPP was approximate 100-200nm and the distribution of nanoparticles was homogeneous. Comparing the UV-visible spectras of the monomer with that of the nano-InTPP, it was shown that spectra the Soret band of monomer at 423nm was split into two red-shifted bands at 433nm and 453nm respectively in UV-vis, the absorbance of Soret band was significantly reduced and the shape of Soret band was obviously widened. The detection optical properties of indium porphyrin had been studied by UV-Vis spectra. Comparing the detection results of the monomer with that of the nano-InTPP, it was shown the detection results of nano-InTPP were obviously better.
  • ;;;
    . 2011, 42(06): 28-0.
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    A facile wet chemical process was developed to fabricate hexagonal CuI powder at normal pressure and temperature. Remarkably, such CuI film displays excellent superhydrophobicity without further modification by low-free-energy materials (thiol or fluoroalkylsilane), and the contact angle reaches 157o. Importantly, such superhydrophobicity property is quite stable even when it is kept in air for about half a year, which makes it have potential applications.
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    . 2011, 42(06): 29-0.
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    With the natural guar gum (GG), montmorillonite modified by cetyl trimethyl ammonium bromide (OMMT) and acrylic acid (AA) as raw materials, N,N'-methylene bisacrylamide (MBA) as crosslinker agent, novel guar gum-g-poly(acrylic acid)/OMMT superabsorbent nanocomposites were prepared by graft polymerization in aqueous solution. The effects of the content of OMMT and concentration of MBA on the water absorbency of superabsorbent nanocomposites were studied. Reswelling capabilities of the superabsorbent nanocomposites were also investigated. The characterization of superabsorbent nanocomposites was carried out by fourier transform infrared spectrometry (FT-IR), scanning electron microscope (SEM) and X-ray diffraction (XRD).The results showed that GG participated in graft polymerization reaction with AA. The OMMT layers were exfoliated and dispersed in the composite at nano size after the polymerization. The introduced 5% OMMT enhanced the water absorbency of superabsorbent nanocomposites,improved reswelling capability when the concentration of MBA was 3mmol/L.
  • Zhuo NI ;;
    . 2011, 42(06): 30-0.
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    In this work, urea-formaldehyde resin/epoxy microcapsules are synthesized and used to design self-healing polyester/carbon fiber composite materials. Mechanical properties, scanning electron microscopy (SEM) and optical microscope (OM) are employed for a study on the microcapsules and self-repairing materials. Carbon fiber can improve the elastic modulus and control the width of cracks. Microcapsules have not only a toughening effect but also a self-healing effect. After stretching, the composite materials appear an internal cracks resulting from the front tip in stress response. Wall ruptures, core materials flow out and wet cracked surfaces, eventually bond cracking. Crack termination is observed in various forms including micro-capsules rupture, carbon fiber termination and other crack hinders across the cracking.
  • . 2011, 42(06): 31-0.
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    Two novel D/A-PTh derivatives having a polythiophene backbone and 1,3,4-oxdiazole derivatives as side groups: poly(3-(2-(4-tert-butylphenyl)-5-(4-vinylphenyl)-1,3,4-oxadiazole))thiophene(P3OXDT) was obtained by Heck coupling reaction of 3-bromothiophene and 2-(4-tert-butylphenyl)-5-(4-vinylphenyl) -1,3,4-oxadiazole and then iron(III) chloride oxidation polymerization; poly(3-octyl-4- (2-(4-tert-butylphenyl)-5-(4-vinylphenyl)-1,3,4-oxadiazole))-co-poly (3-octyl thiophene) (P3O4OXDT-P3OT) was obtained by iron(III) chloride oxidation of 3-octyl thiophene and Heck coupling reaction with 2-(4-tert- butylphenyl)-5-(4-vinylphenyl)-1,3,4-oxadiazole. They were all characterized with UV-vis, 1H NMR, Gel Permeation Chromatography (GPC) and Photoluminescence (PL) spectroscopy and compared with Poly (3-octyl thiophene). All of them showed excellent solubility, good film-formation ability, and high thermal stability. Compared with P3OT, it is obvious that the introduction of the 1,3,4-oxdiazole side groups in P3O4OXD-P3OT can increase the band gap energy. The PL quantum yield of 0.31 for P3OXDT in chloroform is higher than 0.05 and 0.04 for P3OT and P3O4OXD-P3OT, respectively.
  • Yun Zhang FANG
    . 2011, 42(06): 32-0.
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    Abstract: The Fe36Co36Nb4Si4.8B19.2 (FeCo-based) amorphous ribbon was prepared by single roller quench and annealed with joule-heat in flowing atmosphere under tesile stress. The longitudinally driven giant magneto-impedance (LGMI) effect of the stress-joule-heated FeCo-based ribbons were measured with HP4294A impedance analyzer. The results from analyzing the relation between the tensile stress and the character of the stress-joule-heated FeCo-based ribbon LDGMI effect curves shows that, The transverse magnetic easy axial will be induced after the tensile stress applied during the proccess of the FeCo-based ribbon being joule-heated in flowing atmosphere. The shape of the LDGMI curves can be effectively changed by controlling the transverse magnetic easy axial. This result is very important for develop the new GMI magnetic sensor which will be appropriate for various applications in future.
  • Yi-Ou MA
    . 2011, 42(06): 33-0.
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    Abstract: Micro-nano carbon spheres/ordered mesoporous carbon composite coatings were prepared on the stainless steel substrate through the spinning technique and evaporation induced self-assembly using soluble phenolic resins as carbon precursor, F127 as template-directing agent and carbon spheres as filler. The high rhydrophobic surface was obtained by the fluoridation modification and the contact angle could be arrived at 142°. Scanning electron microscope (SEM) indicated that the prepared composite coatings possessed the novel structure consisted of micro drape full of visible mesopores. Under the simulated marine environment, the corrosion potential of modified composite coatings was increased by 0.73V, and the corrosion current was decreased by 3-4 orders of magnitude. The anti-corrosion efficiency was calculated as high as 99.9 %, indicating the excellent protective performance.
  • . 2011, 42(06): 34-0.
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    Nano-Fe3O4 magnetic particles were prepared by chemical coprecipitation method , magnetic rectorite with different contents of Fe3O4 were prepared by rectorite compounding Fe3O4 magnetic particles as different ratios, and phase composition, microstructure morphology and magnetic properties of the samples were tested and characterized by XRD, SEM, TEM and VSM, respectively; Adsorption property to heavy metal ions contained in wastewater and magnetic recovery rate of magnetic rectorite were studied. The results show that the granularity of Fe3O4 magnetic particles is 10 to 25nm, Fe3O4 has good crystallinity and spinel structure; The saturation magnetization(Ms) , remanence magnetization(Mr) and coercive force(Hci) of magnetic rectorite of magnetic rectorite with Fe3O4 content of 25% is 12.867 A?m2/kg、0.355 A?m2/kg、0.195 A??m-1 respectively; When the addition of magnetic rectorite with the loading Fe3O4 content of 16% is 0.4%, and adsorption time is 180 minutes, adsorption capacity of Cu2+, Zn2+, Cd2+ contained wastewater on magnetic rectorite reaches to 17.67,15.65,14.05mg/L, respectively. Magnetic recovery rates of magnetic rectorite with content Fe3O4 of 10% to 25% are 95.6% to 98.4%.
  • chenyihui
    . 2011, 42(06): 35-0.
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    Abstract:To improve the viscoelastic properties, thermal stability and enzymatic resistance of collagen, collagen solution was cross-linked with a novel cross-linker, N-hydroxysuccinimide activated adipic acid (NHS-AA), and the effect of NHS-AA on the physicochemical properties of collagen was investigated. The rheological and thermal properties of cross-linked collagen solutions have been investigated by means of dynamic frequency sweeps and differential scanning calorimeter (DSC). At 25℃, when the concentration of NHS-AA was increased from 0 to 0.03%, the storage modulus (G'), loss modulus (G"), complex viscosity (η*) of collagen solution increased from 0.03 Pa, 0.11 Pa, 0.76 Pa?s to 22.83 Pa, 3.36 Pa, 143.90 Pa?s, respectively. Denaturation temperature (Td) of cross-linked collagen solution was about 2.1 °C higher than that of uncross-linked collagen solution (40.4°C). The sample solutions were lyophilized to become sponges, the resistance to trypsin digestion of these sponges were observed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS–PAGE). The results shown that, after cross-linking, enzymatic resistance were improved significantly.
  • ;;;;ma-tai DING;;
    . 2011, 42(06): 36-0.
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    Polyvinylidene fluoride (PVDF)-Polyvinyl butyral (PVB) blend ultrafiltration membrane was prepared by using phase-inversion technique. An orthogonal table was designed to study the influences of the blend ratio of PVDF/PVB, and the types of polymer and small molecule additives on the performance of the PVDF/PVB blend ultrafiltration membrane. The experimental results demonstrate an optimal PVDF/PVB system as follows: the blend ratio of PVDF/PVB is 8:2, the solid concentration is 20% (w%), polymer additive is PEG-1500 with concentration of 5%, small molecule additive is ethylene glycol and its concentration is 3%. It is found that the contact angle of the membrane decreases from 88° for PVDF to 58°, which clearly suggests that the hydrophily of the membrane is improved. The pore diameter of the membrane is between 0.004~0.005μm, the flux of membrane is as high as 532.2 L?m-2?h-1 and the rejection rate is above 99%.
  • An-Hua LIU
    . 2011, 42(06): 37-0.
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    In this paper, naphthalene mesophase pitch (AR resin) and isotropic coal tar pitch (ICP) were employed as raw materials to prepare carbon fibers. Effects of raw materials on the structure and properties of the resultant carbon fibers were systematically investigated. Results show that the one-dimensionally ordered mesophase structure in AR resin was elongated along the fiber axis during melt spinning, and interfaces were formed between mesophase domains, resulting in stress concentration in these regions. The stress was released in the process of carbonization, and the formed cracks had adverse effects on the mechanical properties of the carbon fibers. In contrast, ICP was free of the ordered structure and hence no preferred orientation formed in the process of melt spinning, and no stress concentration regions and no cracking occurred during carbonization. The amorphous nature made ICP-based carbon fibers poorly graphitized and brought in low mechanical properties. These results show that the nature of pitch has profound effects in the final carbon fibers. Therefore, adjusting nature of the raw materials is an effective way to improve the structure and properties of pitch based-carbon fibers.
  • ;
    . 2011, 42(06): 38-0.
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  • . 2011, 42(06): 39-0.
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    ABSTRACT :By employing multi-walled carbon nanotubes (MWNT) and SiO2 as fillers and silicone as matrix, (MWNT-SiO2)/RTV composites were prepared by three roll mills mixing method and the piezoresistive and dielectric properties of composites were investigated. The results showed that the use of KH570 modified silica could improve the dispersion of fillers in matrix and the interface binding between fillers and RTV. After modified SiO2, the pressure sensitivity of (MWNT-SiO2)/RTV composite become stronger. When the outside pressure is 150 N, the relative resistance of the (MWNT- SiO2)/RTV composite with 5% SiO2 is nearly twice as much or as that of the MWNT/RTV composite and the piezoresistive sensitivity should increase nearly double. In addition, the resistance and pressure showed a good linear relationship. With increasing the aspect ratio of MWNT, the piezoresistive sensitivity of (MWNT-SiO2)/RTV composites is weaker. Dielectric constant of (MWNT-SiO2)/RTV composites decreases with increasing frequency and it increases with the increase of silica content.
  • ; ;;
    . 2011, 42(06): 40-0.
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    Strontium is among the most hazardous radioactive of fission products. The research studied the sodium alginate-CaCl2 immobilized yeast (Saccharomyces cerevisiae) cell bead characters and the adsorption ratio, adsorption quantity and equilibrium curves of static adsorption, and the chromatography parameters for packed column adsorption of strontium based on the biosorption and immobilization advantages. The results showed that the sodium alginate-CaCl2 immobilized yeast cell beads had high specific surface area and mechanical stability. The static adsorption results showed that the packed column had high adsorption quantity, the average adsorption ratio was 88% and the adsorption equilibrium curves could be modeled with Langmuir and Freundlich models. The chromatography with packed column had carried out two runs (four cycles per run) and the results showed that the immobilized yeast cell beads packed column had good chromatography performance with high adsorption ratio, high elution ration, good readsorption ratio and perfect manipulation stability. The average adsorption >90%, the maximum elution ratio with 0.1 mol/L HCl was 98%, the average readsorption ratio after 0.1 mol/L NaCl renaturation was 90%.
  • Xin-Yu WU;Hui-Ying WU ;
    . 2011, 42(06): 41-0.
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    Magnetophoresis is one of the most popular approaches for biological separations. Magnetophoresis on microfluidic chips by utilizing functional magnetic beads has become a hot topic of research in recent years. In this paper, an experimental study on magnetophoretic separation characteristics was carried out by using superparamagnetic beads with the diameter of 1μm in a rectangular microchannel having hydraulic diameter of 114.3μm. The capture and release processes of the magnetic beads in the microchannel were observed and recorded with the help of high speed CCD camera. The relations between the number of captured beads and time and fluid velocity were obtained by imaging analysis. The results show that the number of captured magnetic beads increases linearly with time at high flow rates while at low flow rates it increases initially quickly and then slowly with time. It is also found that for magnetophoretic separation in microchannels there exists a critical flow rate above which the number of captured beads will drop rapidly to a relatively small value and then decreases slowly when the flow rate continues to increase. It is anticipated that the results in this paper are helpful for the optimum design of highly efficient magnetophoretic separators.
  • LUO XiaoBing ;; ;;
    . 2011, 42(06): 42-0.
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    The tribological properties of polyurethane(PU),polyamide66(PA66), poly(ethylene-co-vinyl acetate) (EVA) and poly(vinyl alcohol) (PVA) hydrogels were investigated in the lubrication of physiological saline and plasma substitute and compared with that of pig articular cartilage (POAC). The worn surfaces and the wearing mechanisms were also analysed by using SEM. The results indicate that the average friction coefficients of all samples are higher than that of POAC, among which the average value of PVA is the nearest to that of POAC, but its wear-resistance is not the best. It is also found that the wear-resistance of PU and PA66 are better than that of PVA and EVA, but the tribological coefficient of the formers are bigger than that of the latters.
  • ; ;;;
    . 2011, 42(06): 43-0.
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    Three types of terbium complexes were synthesized by introducing benzoylacetone as the first ligand and 1,10-phenanthroline, triphenylphosphine oxide , 2,2’-dipyridyl as the second ligand, respectively. The structures of above materials were identified by infrared absorption spectra and chemical elemental analysis, and their light mechanism was studied by detail analysis of ultraviolet-visible absorption spectra and fluorescence spectra. The research results indicated that terbium complexes absorb energy by the first ligand when excited, and emit green light owing to 5D4→7F4 electron transition of terbium ion immediately; it is suggested that the fluorescence yield of terbium complexes doesn’t only depend on the energy difference between the singlet excitation state of the first ligand and the triple excitation state of second ligand, but the energy difference between the triple excitation state of the second ligand and the 5D4 energy state of terbium ion.
  • Guo Wang ;LI Xin-Li;;;
    . 2011, 42(06): 44-0.
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    Boron-doped microcrystalline silicon thin films with varying boron doping ratio were prepared using the radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD) method.Then the samples obtained were annealled at different temperature and ambient.It shows that high-crystallity films undergo a decrystallization process, while low-crystallity films go though a recrystallization process. We also find that it is in favor of crystallization under high vacuum annealling circumstance.After annealing, the initial crystalline fractions of the films have an effect on the changing of the surface roughness,and the dark conductivity of the films all has a significant improvement. For high doped films, crystalline fraction, surface roughness and dark conductivity all can be improved.
  • . 2011, 42(06): 46-0.
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    In this paper,The impact of temperature on magnetorheological fluid responsive particles,carrier liquid and additives is studied. The magnetorheological fluid with Excellent temperature performance is prepared.The magnetorheological fluid viscosity-temperature relationship is analyzed. At the same time,the performance of magnetorheological fluid shock absorber at different temperature is discussed.
  • LAISHIQIANG LAI SHIQIANG
    . 2011, 42(06): 47-0.
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    Abstract: In order to study on controlling water body algae, an underwater ozone generator has been developed by electro-hydraulic power impulse technology according to altering the discharge electrode. The structure of underwater ozone generator and the factors influencing ozone productivity have been discussed. Electrical performance of electro-hydraulic power impulse technology have been established and the electrode effective working areas of the ozone generator has been also calculated. The results show that dissociation reaction of lake water and radical oxidation happen by increasing the ozone of electro-hydraulic power impulse technology. Moreover, the production and reaction of ozone are completed in lake water body. By adjusting the electric field intensity, discharged pulse frequency and pulse amplitude of the current, ozone can be obtained as requirement, and it benifit to control eutrophication of water body.
  • Hai WANGJun Huang;;
    . 2011, 42(06): 48-0.
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    Cellulose acetate film was prepared by solution casting method. Composite sensing film can be obtained via immobilization of fluorescent indicator and glucose oxidase on cellulose acetate film. Surface morphology of composite sensitive film and enzymatic activity were analyzed by scanning electron microscope and UV-visible spectrometer. Fluorescent indicator does not leak. The stability of the immobilized enzyme was higher than the free enzyme. All above indicate this kind of cellulose acetate film can be a good immobilization carrier of fluorescent indicator and enzyme.
  • 简报
  • Dong-Liang Jin
    . 2011, 42(06): 49-0.
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    In this study, the CsH5(PO4)2 whiskers and mesoporous phosphosilicate matrix were derived simultaneously from the sol-gel synthesis of tetraethoxysilane (TEOS), orthophosphoric acid (H3PO4) and CsH2PO4 as raw materials, followed by hydrothermal treatment, and aging at room temperature. The obtained CsH5(PO4)2 whiskers have diameters between 1.5-10μm, while mesoporous phosphosilicate matrix possesses a average pore size of 27 nm. The unique process, in which mesoporous structure matrix was prepared simultaneously accompanied with the growth of whiskers, could become a kind of method preparing mesoporous materals.
  • 研究与开发
  • . 2011, 42(06): 50-0.
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    Sulfur metal-organic complexs were synthesized with Zn(NO3)2, Cu(NO3)2 and DDC(Diethyldithiocarbamate) as raw materials. Bright purple emission ZnS:Cu nano phosphors were synthesized through pyrolysis sulfur metal-organic complex at 200℃. The XRD result shows that high temperature phase α-ZnS with hexagonal structure is obtained. According to TEM micrograph, the phosphors are well-dispersed spherical particles with a mean diameter of about 20 nm. The excitation spectra of phosphors with the peak value at 235nm show obvious blue-shift as compared with that of bulk α-ZnS:Cu (at 330nm),which arises from quantum confinement effect that makes the optical band gap of α-ZnS:Cu nanoparticles broadening. Under the excitation of 235nm, the emission bands around 285nm, 396nm, 486nm and 545nm are detected, and the emission band around 396nm is the strongest. With the increase of copper ion concentration, the luminous intensities of all emission bands increased firstly and then decreased. The intensity achieves the maximum as the content of copper ion is 1.0%.