30 March 2014, Volume 45 Issue 06
    

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    研究 开发
  • . 2014, 45(06): 1-0.
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    The multi-walled carbon nanotubes (MWCNTs) and α-Sexithiophene (α-6T) bilayer were taken as the active layer, and silicon dioxide (SiO2) was used as the insulating layer. Titanium/aurum (Ti/Au) were made as the electrode for the prepared OTFT gas sensor,of which the ratio of channel width to length was 640. The real-time response characteristics of the sensor exposed to nitrogen dioxide (NO2) were tested, and the effect of NO2 on the multi-parameters of the OTFT sensor, such as threshold voltage and carrier mobility, was analyzed. The results showed that, the OTFT device based on MWCNTs/α-6T bilayer performed better electrical properties, and the carrier mobility reached 3.0E-2cm2/V·s. The OTFT gas sensor showed the high response when exposed to NO2, and the time of response and recovery were short. The trace 0.2 ~ 1ppm NO2 were detected and the sensor also had the good repeatability. It was feasible to take the multi-parameters to present the gas response results. Morphology analysis showed that the special feature of the bilayer was helpful for improving the gas sensitivity.
  • 工艺 技术
  • ;;;
    . 2014, 45(06): 2-0.
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    Abstract: Thiolated chitosan derivative (CS-PEG-PEI) was synthesized by grafting double carboxy-terminated PEG and partly thioled polyethylenimine (PEI-SHx) onto chitosan with NHS/EDC as catalyst. The chemical structure of polymer was characterized by the fourier transform infrared spectroscopy(FT-IR) and proton nuclear magnetic resonance(1H NMR), the self-assembled nanoparticles was prepared by probe sonication-dialysis method. The measurements of transmission electron microscope(TEM) and dynamic light scattering(DLS) indicated that the self-aggregates were nanoparticles, this novel nanoparticle system was promising to be a good drug carrier and gene carrier.
  • 研究 开发
  • YE Dai Yong;
    . 2014, 45(06): 3-0.
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    Acrylic acid (AA) and acrylamide (AM) were simultaneously grafted onto the surface of nanocellulose whiskers (NCW). The AA, AM-g-NCW was analyzed by infrared spectroscopy (FTIR) and polarizing optical microscopy (POM) .At the same time, the effects of adsorption time, adsorption temperature, adsorbent dosage and initial concentration on its Cu2+ adsorption properties were studied. The experimental results showed that AA and AM were successfully grafted onto the NCW. The added Cu2+ effected the liquid crystalline texture of AA, AM-g-NCW. AA, AM-g-NCW had best adsorption effect for Cu2+ when adsorption time was 8h, adsorption temperature was 35 ℃ and adsorbent dosage was 0.02g. The adsorption isotherm could be well fitted in with Langmuir equation.
  • SHAO QING HUI ;
    . 2014, 45(06): 4-0.
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    Regular structure block ionomers solution (N, N-dimethylformamide solvent) was obtained through stepwise addition polymerization of PEG/IPDI/DMPA and by introducing organic amines to neutralize. Then, the DCOIT nanocasules were prepared by the self-assembly encapsulation of the hydrophobic functional organic molecule DCOIT by the block ionomers in the aqueous phase interface. The structure and properties of the block ionomers was characterized by FT-IR and surface tension analysis methods. The encapsulation effect of the block ionomers on DCOIT was displayed by the particle size measurement. The morphology and release behavior of DCOIT nanocapsules were studied by the frozen slice section TEM and Uv-vis spectrophotometry analysis methods respectively. The block ionomers with desired polyurethane structure was confirmed by the FT-IR analysis. Particle size and frozen slice section TEM analysis methods demonstrate that the DCOIT nanocapsules have been formatted. Study of the Uv-vis spectrophotometry analysis shows that the release rate of the nanacapsules with wall/core ratio varied from 2:1 to 1:1 was large in the early stage, and then experienced a deceleration stage, after that, the rate increased sharply, Furthermore, with the decrease of the wall/core ratio, the deceleration stage gets shorter. Finally, the release mechanism of the DCOIT nanocapsules were initially explored and discussed.
  • . 2014, 45(06): 5-0.
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    Abstract : The crystal structure, electronic structure, optical properties and the band edge position of pure anatase TiO2 and anatase TiO2 with S, La single doping and co-doping are investigated by the first principles plane waves ultra-soft pseudopotential. The results show that crystal lattice constants and bond lengths between atoms and atomic charges of the doped TiO2 are changed, which causes the surface of the body eight dipole moment increase. This method is favorable for effective separation of photo-generated electron-hole pairs and will improve the photocatalytic performance of TiO2. The band gap appears impurity level when S is doped in TiO2 so that the absorption threshold wavelength red shifts to visible light region. However, impurity level appeared in the conduction band when La is doped in TiO2 rather than the band gap, with band gap decreasing, the absorption spectrum threshold wavelength red shift a little. Spectral response range extends to visible light when S and La are co-doped in TiO2, which results in oxidation and reduction is enhanced and the photocatalytic efficiency is improved.
  • ;Bai YANG ;
    . 2014, 45(06): 6-0.
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    Fe-based magnetic powder cores by coating different size of pure iron particles with different content of silicon resin have been fabricated via powder compacting molding process. The Effects of particle size and content of silicon resin on density, DC and AC magnetic properties of magnetic powder cores were studied systematically. The best particle size and content of silicon resin were searched in order to prepare high-performance magnetic powder cores with high density, low loss and high magnetic induction. The investigation shows that, for coating the same particle size of the iron particles, the eddy loss of magnetic powder cores decreases with increasing the coating content of silicon resin. The density of the magnetic cores is also lower with the increasing content of silicon resin, which results in the decrease of saturation magnetic induction. With the same content of silicon resin, both the density and the eddy loss of magnetic powder cores increase accompanied by the increased particle size of pure iron particles. While the magnetic hysteresis loss decreases with increasing the particle size. The results revealed that high-performance magnetic powder cores with high density and good soft magnetic properties can be synthesized when coating the pure iron particles of the size for 120 μ with the silicon resin content of 0.5 wt%. High magnetization B4k (H = 4000 A/m) of 0.96 T and low loss Ps (B = 1 T, f = 400 Hz) of 69 W/kg are obtained for Fe-based magnetic powder cores in this work.
  • TIngkai Zhao;Wang-Jin WANG
    . 2014, 45(06): 7-0.
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    ??β-cyclodextrin(β-CD)/multi-walled carbon nanotube (MWCNT) composite was prepared by the electrostatic self-assembly method. The electrochemistry catalytic effects of pH, scanning rate,catalytic time,raw material ratio and concentration of liquid on the glassy carbon electrode coated with β-CD/MWCNTs composite were studied by cyclic voltammetry.The experimental results showed that the electrochemistry catalytic effect of β-CD/MWCNTs composite on the p-nitrophenol was obvious, and it is was controlled by the surface process. The optimum catalytic conditions were determined,potassium hydrogen phthalate as buffer solution, quiet time of 40 s, the mass ratio of carbon nanotubes and β-CD is 1:3. The electrochemical determination method of p-nitrophenol using a glassy carbon electrode coated with a β-CD/MWCNTs composite was developed by differential pulse voltammetry. The results indicated that the redox peak currents of p-nitrophenol were linear while the p-nitrophenol concentration range was from 1.3 ×10-6 to 3.5× 10-4 mol/L, and the linear coefficient of the redox peak current was 0.9985 and the detection limit was 1.233×10-7mol/L.
  • Chun-Tao GAO; ;Qu-Fu WEIHui QIAO
    . 2014, 45(06): 8-0.
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    Abstract: The TiO2 nanofibers were prepared by combing sol-gel, electrospinning and high temperature calcinations techniques. Then the grinded TiO2 nanofibers and PA6 were blended and spun in a twin-screw extruder to prepare melt-spun PA6/TiO2 composite filaments. TEM and SEM were used to characterize the structural morphology of the TiO2 nanofibers. The video microscopy was applied to observe the morphology of the composite filaments. Differential scanning calorimetry (DSC), rheometer and fiber strength tester were adopted to analyze the crystallization, rheological and mechanical properties of the composite filaments. The results showed that the composite filaments with relatively low TiO2 amount presented higher degree of crystallinity, shear viscosity, and breaking strength.
  • Nan JIANG;
    . 2014, 45(06): 9-0.
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    Preparations of Mn-Mo, Mn-Mo-V, Mn-Mo-Fe and Mn-Fe-V anodes anodically deposited for oxygen evolution over chlorine evolution in seawater electrolysis are carried out. XRD and FESEM analysis reveal that the prepared oxide electrodes have a γ-MnO2 structure. The initial oxygen evolution efficiencies are all close to 100%. The Mn-Fe-V anode is the most stable electrode during the seawater electrolysis, and it could keep high efficiency for oxygen evolution during electrolysis. The main reason for the decrease of oxygen evolution efficiency is dissolution and peeling off of the manganese oxides during electrolysis.
  • huifang LUZhenghou Zhu
    . 2014, 45(06): 10-0.
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    Fe73.5Cu1Nb3Si13.5B9 nanocrystalline strip exhibit excellent soft magnetic properties, and is widely used in the field of switch power supply, etc. But Fe73.5Cu1Nb3Si13.5B9 nanocrystalline strip magnetic core exist serious infiltration problem of epoxy resin in the process of encapsulation, which limits the application of nanocrystalline strip. We invest the oxidation process on the surface of the strip. The surface of the strip distribute uniformity, smooth, dark red brown oxide film. With strong binding force with the strip, oxide film can be used as a transition layer of strip matrix and epoxy resin, so it can improve the infiltration between the strip and epoxy resin. Compared with not strip surface oxidation treatment, the initial permeability and saturated magnetic induction intensity of the strip with surface oxidation treatment increases by 14.6% and 4.3% respectively, and the coercive force is reduced by 21.6%.
  • Zhi-Qing YANG;;TIAN ron min
    . 2014, 45(06): 11-0.
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    In this paper, two nano-TiO2 and MnO2 oxides were synthesized by hydrothermal method, and three kinds of modified activated carbon fiber (ACF) electrodes were fabricated by dip coating process using these oxides. The morphology and dimensions of the oxides was characterized by TEM and the electrochemical property of modified ACF electrodes was evaluated with cyclic voltammetry (CV). The results showed that two oxides are nanometers with one-dimensional characters, that is, in the shapes of a rod for TiO2 and a tube for MnO2. Besides, an enhancing electrical conductivity of the modified ACF electrode was observed after coating with both TiO2 and MnO2. And the electronic density of modified ACF electrodes lied in the sequence of ACF < TR/ACF < MT/ACF < TR/MT/ACF. Their electro-catalytic degradation characteristics for dye wastewater with high salinity as a model compound were compared. The results indicated that the COD removal rate was up to 69.4 % with the ACF electrode coated with TiO2 and MnO2, and only 54.4 % with the ACF electrode without oxides, implying that the electrocatalytic activity increasing of the ACF electrode was correlated to its one-dimensional structure of the nanocomposite.
  • ;;
    . 2014, 45(06): 12-0.
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    Abstract:The ordinary zinc powder was milled 13 hours with roller vibration milling and obtained irregular sheet nanoscale zero-valent zinc particles(NZVZ) and the particle size is between 20 and 30 nm. This paper here is focused on the degradation of water soluble methyl orange(MO) by NZVZ, and rotation speed of magnetic stirrer, NZVZ dosage, initial MO concentration and NaCl dosage were studied systematically. It was found that the degradation of MO with 2 g/l of NZVZ is 98.5% in 60 min, has 60.3% more than 4 g/l of ordinary zinc powder, the Sulfanilic?acid and 1,4-Benzenediamine,N,N-dimethyl- as degradation progress products were identified. Degradation was enhanced with increase of rotation speed and NZVZ dosage, while decreased with increase of initial MO concentration. Moreover, the existence of NaCl can promote the reaction procress and degradation increased with increase of NaCl dosage. Kinetic analyses based on the experimental data elucidated that the degradation process followed the pseudo first-order kinetic equation.
  • Zi-fen ZHAO;
    . 2014, 45(06): 13-0.
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    In this paper, Fe3O4 magnetic nanoparticles were prepared by chemical co-precipitation method and surface modification by sodium oleate were introduced. The kerosene-based Fe3O4 magnetic fluid was prepared by using kerosene as carrier liquid. Compared with differences of Fe3O4 magnetic particles coated by sodium oleate in the conditions of PH = 5 and PH = 10.5. It showed that the nanoparticles were coated successfully by sodium oleate. The saturation magnetization of Fe3O4 magnetic nanoparticles is 58.01emu/g, the saturation magnetization of magnetic fluid prepared is 20.2emu/g, and Fe3O4 particles were well-dispersed. Although in the case of PH = 10.5, Fe3O4 magnetic particles coated by sodium oleate had a higher saturation magnetization (67.76emu/g), but the magnetic fluid was less stable and had a obvious settlement phenomenon.
  • . 2014, 45(06): 14-0.
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    In this work, expanded graphite was prepared from natural flake graphite with concentrated nitric acid. Zinc processed by mechanical milling and expanded graphite were dispersed in the distilled water and ethanol. Then, they were processed via ultrasonic of 30KHz by eight hours to synthesize series of composites, consisting of ZnO nanorod and graphene(ZnO/G) with an excellent structure. The influence of different proportion of zinc and expanded graphite on the photocatalytic activity of ZnO/G composites was studied. The photocatalysts were characterized by X-ray diffraction(XRD), scanning electron microcopy(SEM), transmission electron microcopy(TEM)and UV-Vis absorbance spectroscopy. The results reveal that ZnO synthesized by ultrasonic is short rod-like with the wurzite hexagonal structure and grows on the surface of graphene equably. The diameter of ZnO nanorod is about 20 nm. The degradation rate of methyl orange by ZnO/G composites prepared by different proportions vary greatly. The photocatalytic activity of ZnO/G composites is prior to ZnO when the content of zinc in reactant is 1.0 g.
  • Xiao-Feng ZHANG ;;;shen lin
    . 2014, 45(06): 15-0.
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    The inorganic/organic luminescent nanocomposite film based on polyoxometalate anion [Tb(P2Mo17O61)2]17- and polyamidoamine (PAMAM) dendrimer was prepared by layer-by-layer technology. The components, structures and properties of the film were characterized by UV-Vis, XPS, AFM and fluorescence spectroscopy. The results showed that electrostatic interaction exists between inorganic and organic component. The growth processes of the assembled film were quantitative and highly reproducible from layer to layer. The surface was smooth and dispersed with uniform spherical particles. Compared with the solid Tb(P2Mo17O61)2,the excitation spectrum of Tb(P2Mo17O61)2 /PAMAM film showed a board ligand to metal charge transfer band. The film exhibited the characteristic emission peaks of Tb3+. In addition, a new peak appeared in the emission spectra, which may result from the lower symmetry of Tb3+ crystalline field in the film.
  • Xin-Ming ZHANG;S.L. Zhu ;; Xian-Jin YANG
    . 2014, 45(06): 16-0.
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    TiO2 nanotubes was prepared by anodic oxidation method on pure Ti surface, then the microRNA was loaded in the nanotubes by lyophilization to build composite coating. The TiO2/microRNA composite coating was characterized by SEM, TEM and fluorescence microscope. The release behavior of microRNA and its furthrer function was analysised. The results showed that, microRNA successfully deposited in TiO2 nanotubes, and sustained release delivery for 12 h. Fluorescent images indicated that the microRNA was transfected into osteoblasts, ALP activity assay further indicated that the microRNA promoted the osteogenic differentiation.
  • . 2014, 45(06): 17-0.
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    Zn doped TiO2 powders (Zn-TiO2) were synthesized by sol–gel method. The obtained powders were characterized by XRD, TEM, UV-Vis, PL, respectively. The results show that Zn-doping can decrease the phase transition temperature, broaden the absorption spectrum to the visible light region, and inhibit the recombination of photoelectron-hole pairs. The experiments of photocatalytic degradation of methylene blue (MB) suggest that the photocatalytic activity of the Zn-TiO2 powders at Zn :Ti =0.045(molar ratio) and the calcinated temperature of 400℃ is the best. Under the fluorescent light irradiation, the degradation rate of the Fe-TiO2 sample to methyl blue reaches 95.77%, which is obviously higher than 44.95% of P25, the pure TiO2 photocatalyst made in Degussa, German.
  • TIAN WANG;
    . 2014, 45(06): 18-0.
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    A stable TiO2 sol was synthesized from titanium isopropoxide by colloidal sol-gel route. Mesoporous TiO2 membranes were prepared with tubular Al2O3 microfiltration membrane of 100nm pore size as support by dip-coating method. The effect of preparation process on integrity and pore structure of mesoporous TiO2 membrane was studied in detail. In addition,the absorption of acid orange 7 and methylene blue onto unsupported mesoporous TiO2 membrane was researched. Defect-free mesoporous TiO2 membranes were obtained from TiO2 sol added appropriate amount of PVA and HPC as binder by time-controlled dip-coating followed by calcination at 450℃ for 1h. The thickness of TiO2 membrane is about 0.5μm and the pore size distributes in the range of 3-10nm. The absorption of acid orange 7 and methylene blue onto mesoporous TiO2 membrane varies with pH value. It implies that adusting pH value may decrease membrane fouling caused by the adsorption.
  • GUO Zhi Jun;
    . 2014, 45(06): 20-0.
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    The aligned TiO2 nanotube arrays on Ti substrate were fabricatied in different electrolytes by means of anodization. The effects of electrolyte components, voltage and reaction time on the morphology and microstructure of TiO2 nanotube arrays were investigated in this study, and the growth mechanism of TiO2 nanotube arrays was also discussed. Besides, the nanostructure, morphology, hydrophilicity, roughness and surface energy of the TiO2 nanotubes were characterized and analyzed using SEM, surface roughness tester and water contact angle testing. The results show that, the diameter, length, morphology, roughness, hydrophilicity and surface energy of TiO2 nanotubes have changed in different anodization processing parameters, in which the effect of the electrolyte component is most obvious.
  • meng meng wang
    . 2014, 45(06): 21-0.
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    Hierarchical mesoporous CeO2 nanosheets were prepared by using camellia flower petal as biotemplate through thermal decomposition. For characterization of texture,X-ray diffraction spectroscopy (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), atomic force microscope (AFM), UV-Vis diffuse reflectance spectra (UV-Vis/ DRS) and nitrogen adsorption-desorption measurements were adopted. The results demonstrate that the biomorphic structure of fluorite structure CeO2 nanosheets with the thickness of ca. 6 nm was obtained. There exists mesopores with pore size of about 15 nm on the surface of the CeO2 nanosheets. Hierarchical mesoporous CeO2 nanosheets exhibit a clear red shift (35 nm) comparing with bulk CeO2, which could be excited by visible irradiation and enhance the visible activity. Hierarchical mesoporous CeO2 nanosheets display the superior photocatalytic activity for the degradation of methylene blue under sunlight irradiation, with a degradation rate as high as 98%. It was contributed to the smaller crystallite size, enhanced higher surface area of the ceria nanosheets.
  • 工艺 技术
  • . 2014, 45(06): 22-0.
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    Abstract: Two novel well-defined amphiphilic block copolymers P4VP-b-PMAPEG and PAA-b-PMAPEG were synthesized via Reversible Addition-Fragmentation chain Transfer(RAFT) process. Using these two amphiphilic block copolymers modified Fe3O4 magnetic nanoparticles were prepared through polyol reduction. The as-synthesized magnetic nanoparticles were characterized by Fourier-transform infrared spectroscope(FT-IR), X-ray powder diffraction (XRD),and transmission electron microscope(TEM). Characterization revealed that the magnetic nanoparticles show Spherical particles of uniform size and the average diameter of 20nm. Vibrating sample magnetometer (VSM) test results show that, at room temperature, the applied magnetic field, the modification of Fe3O4 magnetic nanoparticles by PAA-b-PMA PEG and P4VP-b-PMAPEG saturation magnetization were 63.1 emu / g and 50.2emu /g, Respectively. the magnetic nanoparticles presented superparamagnetic.
  • Ming-Long ZHONG ;;;;
    . 2014, 45(06): 23-0.
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    Large-area α-Fe2O3 nanobelts were synthesized by heating the Fe film on silicon substrate in air, using a very simple hotplate technique. The morphologies, crystal structures, growth mechanism and magnetic properties of the nanobelts were investigated. The results show that single-crystal α-Fe2O3 nanobelts grow perpendicularly to the substrate along [110] direction with a very sharp tip about 10-50 nm. The length of the nanobelts are from hundreds nanometers to several micrometers. A diffusion mechanism is responsible for the α-Fe2O3 nanostructure growth at relatively low temperatures. The Morin temperature TM and Néel temperature TN of α-Fe2O3 nanostructures are only 113 K and 814 K, respectively, which are about 150 K lower than those for their bulk counterpart.
  • ZHOU Xiao-Liang ;
    . 2014, 45(06): 24-0.
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    Reaction sintering and ultrasonic treatment were used to synthesize Al2O3 particles reinforced aluminum matrix composites from SiO2 powder. Microstructure of the composite, the morphology and the size of the particles as well as the particles distribution in the as-prepared composites were investigated by X-ray diffraction, differential thermal analysis, scanning electron microscope, and energy dispersive spectroscopy. Electronic universal testing machine was used for room-temperature tensile experiment. It is shown that Al2O3 particles, which are about 1μm in size, have been obtained and aggregate in the compact sintered at 800℃ for 8 h. Composites with uniformly-distributed Al2O3 particles were obtained by dissolving the as-sintered compact in liquid aluminum under high-energy ultrasound with a power of 1.0KW/cm2. The size of Al2O3 particles after dissolving almost has no change. The tensile strength of the composite is 110.6 MPa, which is increased by 20.2% compared with pure aluminium (92.0 MPa).
  • lingling lin;;Shuang-Shuang Theng;; ;ma-tai DING
    . 2014, 45(06): 25-0.
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    The influences of lanthanum and cerium doping on the performance of TiO2 ultrafiltration membrane were investigated. The significant TiO2 crystal structure change with the increase of calcination temperature can be effectively suppressed by lanthanum doping. Lanthanum and cerium doping can not only effectively control the particle and pore sizes in membrane layer, but also improve the acid and alkali resistance. TiO2 membrane layers were obtained with particle sizes of 60-80 nm and bore diameters of 10-60 nm. Lanthanum and cerium doping TiO2 membrane layers were obtained with particle sizes around 50 nm and bore diameters of 10-20 nm. In addition, the performance of lanthanum doping is better than cerium doping.
  • Bin Liu;;Lei Sun;yanbao zhao
    . 2014, 45(06): 26-0.
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    This paper presents a rapid growth method to synthesize Ag@Al2O3 core/shell nanodendrites (NDs) crystals on Al foil through an electroless galvanic displacement reaction between Al foil and [Ag(NH3)2]+ ion. The morphology of and structures of the as-synthesized Ag@Al2O3 nanodendrities were characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray powder diffraction (XRD). The results show that the as-synthesized surface modified Ag nanodendrites exhibit a face centered cubic crystalline structure. The presence of a uniform thin film of Al2O3, depositing on the surface of Ag NDs can prevents its possible oxidation and help maintaining the dendrites shape. This synthesis method is facile and environmental friendly without using any additional reductant or capping agent.
  • 研究 开发
  • ;;;Zhu LONG;
    . 2014, 45(06): 27-0.
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    The increasing awareness regarding green chemistry has prompted the need for an eco-friendly approach to synthesize nanoparticles that is simple, cost-effective, and compatible with biomedical and pharmaceutical applications. A simple, green method was developed for the synthesis of silver nanoparticles (AgNPs) by using Dialdehyde Chitosan (D-CTS) as the reducing and stabilizing agents. D-CTS was prepared from the oxidation of chitosan by sodium periodate, and its degree of oxidation was determined by elemental analysis and Fourier-transform infrared spectroscopy (FT-IR). The synthesized AgNPs were characterized by UV-Vis spectroscopy, dynamic light scattering (DLS), FT-IR, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate: the morphology and size distribution of the AgNPs were found to vary with the dialdehyde content of D-CTS and the pH value of the reaction solution. The aldehyde groups and the amino groups were the major agents that stabilized the AgNPs. XRD results indicated the presence of nano-silver with face-centered cubic structure.SEM results showed that nano-silver particles of 30-40 nm in size were homogeneously dispersed in the solution. Meantime, the synthesized AgNPs remained stable in normal condition.
  • Dong Ya YANG
    . 2014, 45(06): 29-0.
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    PPS/PTFE and two different nanoparticles reinforced PPS-PTFE composites were prepared by mechanical blending-molding-sintering method. The tribological and wear behavior of the three composites sliding under different load, temperature, velocity were studied with a MRH-3 block-on ring friction and wear tester. The worn surface and transfer film of the composites were inspected by scanning electronic microscopy (SEM), and the abrasion mechanical was discussed. The results showed that with the addition of nano-Al2O3 and SiO2, the wear resistance of PPS-PTFE blends is improved, and the best anti-wear performance was obtained when the content of nano filler reached 5%. Nano-SiO2 reinforced composites are more suitable for working under heavy load and high temperature than nano Al2O3 reinforced one. The wear mechanism of the two nanoparticles filled composites is abrasive wear.
  • Shuai YUAN
    . 2014, 45(06): 30-0.
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    Highly ordered TiO2 nanorod arrays were prepared using Ti mesh as titanium source in HCl and H2O2 system. The microstructure morphology and crystallinity were controlled by the modification of the molar ratio of HCl to H2O2. Evaporation induced self-assembly (EISA) strategy was also used to introduce TiO2 nanoparticles into nanorod arrays. The photocatalytic performance of composite catalyst was investigated by using Methylene Blue (MB) as simulated contamination. The structure and compositions of photocatalysts were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). Effects of incorporation of TiO2 nanoparticles on the charge transfer rate of the TiO2 nanorod arrays were investigated with Electrochemical Impedance Spectroscopy (EIS) analysis. The TiO2 nanoparticles/nanorod arrays composite photocatalyst shows high photoelectrocatalytic activity.
  • 工艺 技术
  • Changyu LI ;
    . 2014, 45(06): 32-0.
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    The mesoporous nanosheets of In(OH)3 was prepared by one-step hydrothermal method using In(NO3)3 and hexamine (HMT) as the precursor. X-ray power diffraction (XRD), UV–vis diffuse reflectance spectroscopy (DRS), Fourier transform infrared spectrometry (FT-IR) and transmission electron microscopy (TEM) were employed to investigate the structure, morphologies, and optical properties of samples. Toluene was used as a probe molecule to investigate the photocatalytic activity of the mesoporous nanocubes of In(OH)3. The results showed that the photocatalytic activity of the mesoporous nanocubes of In(OH)3 was more stable and higher than that of Degussa P25 . The degradation rate of toluene reached 90% under UV irradiation after the In(OH)3 was recycled used for 12 times. The mechanism of high activity of the mesoporous nanocubes of In(OH)3 was also discussed.
  • 研究 开发
  • Ping BIAN;Chun-Yang Kong
    . 2014, 45(06): 33-0.
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    Different concentration of ZnO:C thin films were deposited on quartz glass substrates by a radio-frequency (RF) magnetron sputtering technique. The structure, Raman and electrical properties of ZnO:C film were investigated by X-ray diffractometer, Raman scattering spectrum and Hall measurement system. Then, we explore the role of C in the ZnO:C film. The results indicate that all films perform the ZnO wurtzite structure with preferred c-axis orientation. The n-type conductivity enhances with the increase of C dopant, and the main explanation to be that C substitute for zinc site and act as donor.