A novel and efficient methodology for obtaining highly active photocatalyst of bi phase TiO 2 with small particle size and high specific surface area was developed by solvent evaporation induced crystallization (SE...
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A novel and efficient methodology for obtaining highly active photocatalyst of bi phase TiO 2 with small particle size and high specific surface area was developed by solvent evaporation induced crystallization (SEIC) method at low temperature. The prepared TiO 2 powder was characterized with X ray diffraction (XRD), transmission electron microscopy (TEM) and BET surface areas. The photocatalytic activity was evaluated by the photocatalytic oxidation of acetone in air. The results showed that the photocatalytic activity of the TiO 2 powder prepared by this method approached that of Degussa P25. This may be attributed to the fact that the prepared TiO 2 powder had larger specific surface areas (265 m 2·g -1 ) and smaller crystallite size (about 5 nm), but relatively low crystallinity, as compared with Degussa P25.
Ti 3SiC 2 materials have been fabricated by spark plasma sintering of the elemental powders with the addition of Al. At the heating rate of 80 ℃/min and under the pressure of 30 MPa, the ideal synthesis temperature o...
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Ti 3SiC 2 materials have been fabricated by spark plasma sintering of the elemental powders with the addition of Al. At the heating rate of 80 ℃/min and under the pressure of 30 MPa, the ideal synthesis temperature of Ti 3SiC 2 is in the range of 1 1501 250 ℃. The addition of Al is in favor of the formation of Ti 3SiC 2. The synthesized compound has the molecular of Ti 3Si 0.8Al 0.2C 2 and lattice parameters of a=0.306 9 nm, c=1.767 0 nm. Its grain is plane-shape with a size of about 50 μm in the elongated dimension. The prepared material has Vickers hardness of 3.55.5 GPa(at 1 N and 15 s) and is as readily machinable as graphite’s.
CoSb/sub 3/ micrometer powder was synthesized by solid-state reaction using high purity powder of Co, Sb as the starting materials. CoSb/sub 3/ nano-powder and block material with nanostructure were prepared by high-e...
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CoSb/sub 3/ micrometer powder was synthesized by solid-state reaction using high purity powder of Co, Sb as the starting materials. CoSb/sub 3/ nano-powder and block material with nanostructure were prepared by high-energy ball-milling and by Spark Plasma Sintering (SPS), respectively. The influence of mass ratio of big balls and small balls, milling speed and time on particles size of CoSb/sub 3/ powder, and sintering temperature and time on grains size of CoSb/sub 3/ were investigated. The influence of nanostructure on thermal transport properties of CoSb/sub 3/ was also studied.
Since some transition metal diborides have the same crystal structure with TiB 2, which can react with TiB 2 to form solid solution by adequate technique. With ZrB 2 used as additive, the TiB 2-ZrB 2 solid solution wa...
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Since some transition metal diborides have the same crystal structure with TiB 2, which can react with TiB 2 to form solid solution by adequate technique. With ZrB 2 used as additive, the TiB 2-ZrB 2 solid solution was prepared by hot pressing. The effects of additive content on mechanical properties of composite were investigated. The microstructure analyzing were employed by EPMA, SEM and TEM. It is shown that TiB 2 can partly form solid solution with ZrB 2 and redound to gain uniform grains, which results in the increase of mechanical properties.
Composite particles consisting of polyaniline( PAn) core and barium tilanate ( BaTiO3) Layer shell were synthesized. The PAn-BaTiO3 composites particles were characterized with TEM and XRD. The dielectric behavior of ...
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Composite particles consisting of polyaniline( PAn) core and barium tilanate ( BaTiO3) Layer shell were synthesized. The PAn-BaTiO3 composites particles were characterized with TEM and XRD. The dielectric behavior of particles was tested and the electrorhcologicak(ER) behavior of the suspensions of PAn/ BaTiO3 panicles in chlorinated paraffin oil with a 20vol % was investigated under DC electric field. The results show that the ER effect of composite particle is far stronger than that of pure polyaniline and barium titanate which mere synthesized by the stone method. pH and thickness of BuTiO3 have an important. influence on the ER effects.
The influence of pretreatment of fibre on interfacial and mechanical properties of glass fibre/ polypropylene composites was investigated. Firstly, the glass fibres were coated with the blends of m-IPP (maleic anhydri...
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The influence of pretreatment of fibre on interfacial and mechanical properties of glass fibre/ polypropylene composites was investigated. Firstly, the glass fibres were coated with the blends of m-IPP (maleic anhydride grafting isotatic polypropylene ) and m-APP ( maleic anhydride grafting amorphous polypropylene) in different, ratios. Secondly, the interfaced reaction of the coated composites was analysed by FTIR, which shows that the interfacial chemical reaction between m-IPP/m-APP in the fibre coating and the fibre surface- bound coupling agent is in existence. Thirdly, the microstructure of the coated composites wax studied by SEM. The results indicate that the coating treatment is effective on improving interfacial adhesion of the, fibre-matrix and the right amount of m-APP added to the coal impels the plastic deformation surrounding the point of cracks , which makes cracks turn to region and prevents from further interface debonding. Lastly, the mechanical properties were evaluated by measurement, of the flexural strength and impact strength of the composites. It was found that, the flexural strength and impact strength of the composites with coating fibre are higher than those of uncoating fibre composite. The results of these investigations draw the conclusion that the pretreatment of fibre with m-IPP/m-APP blends can form an optimize interlayer between the fibre and the PP matrix, which improves both the strength and lough-ness of the composites.
Both titanium and germanium were introduced into silicon dioxide system by sol-gel method to move its region of anomalous dispersion caused by IR resonance absorption towards the wavelength of CO 2 *** is indicated b...
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Both titanium and germanium were introduced into silicon dioxide system by sol-gel method to move its region of anomalous dispersion caused by IR resonance absorption towards the wavelength of CO 2 *** is indicated by IR absorption spectra that as the content of SiO 2 decreases in this glass system TiO 2 and GeO 2 tends to exist in their own *** for the gel glass with a composition of 40SiO 2·30TiO 2·30GeO 2,when the temperature is below 600℃,germanium atoms exist mainly in Ge-O-Ge *** the temperature increasing from 800℃ to 1000℃, titanium atoms in Si-O-Ti bonds almost transform into Ti-O-Ti ***,a large number of Si-O-Ti and Si-O-Ge bonds formed when the temperature approaches 800℃,which makes a notable IR absorption band round the wavelength of CO 2 ***, sol-gel based SiO 2-TiO 2-GeO 2 gel glass is a candidate material for CO 2 laser hollow waveguide.
Doped SrTiO3 capacitor-varistor multifunctional ceramics were fabricated by a single sintering process. AC complex impedance analysis was performed to investigate electrical features of grains and grain boundaries for...
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Doped SrTiO3 capacitor-varistor multifunctional ceramics were fabricated by a single sintering process. AC complex impedance analysis was performed to investigate electrical features of grains and grain boundaries for both as-reduced ceramic and reoxidized ceramics. The results showed that the as-reduced ceramic exhibited inductive response at high frequencies above 2 MHz, which is attributed to the contribution of electron behavior in semiconducting grains. The high frequency inductive response disappeared in impedance plots of reoxidized ceramics.
Infrared radiant powder was synthesized by conventional ceramic processing techniques by using Fe2 O3, MnO2, CuO, Co2 O3 and kaolin as raw materials. A novel infrared radant glaze was developed by introducing the infr...
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Infrared radiant powder was synthesized by conventional ceramic processing techniques by using Fe2 O3, MnO2, CuO, Co2 O3 and kaolin as raw materials. A novel infrared radant glaze was developed by introducing the infrared radiant powder into glazing as a functional additive. Infrared radiant characteristics of the powder and the glaze were investigated. The optimum content of infrared radiant powder in glazing was ascertained to be 5% . The infrared radiant glaze exhibits significant antibacterial and antifungal Junctions due to the thermal effect of infrared radiation. Antibacterial percentages of the glaze reach 91% - 100% when Escherichia coli, Staphylococcus aureus and Bacillus subtilis are used as model bacterium respectively, while antifungal percentage of the glaze exceeds 95% when Penicillum citrinum is used as model fungus.
b Department of Chemistry, Wuhan University, Wuhan, Hubei 430072, China The action of β ( N selenomorpholine) ethyl phenyl ketone hydrochloride and 4 ( N selenomorpholine) 2 butanone hydro chl...
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b Department of Chemistry, Wuhan University, Wuhan, Hubei 430072, China The action of β ( N selenomorpholine) ethyl phenyl ketone hydrochloride and 4 ( N selenomorpholine) 2 butanone hydro chloride on Escherichia coli and Staphylococcus aureus was studied by microcalorimetry. Differences in their capacities to affect the metabolism of this bacterium were observed. The kinetics shows that the selenomorpholine compounds had action on the metabolism process of Escherichia coli and Staphylococcus aureus. The rate constant ( k ) of the studied bacterium in the presence of the drugs are concentration dependant. The growth rate constants decrease with an increase in the mass of the selenomorpholine compounds, but their relationship is different. As deduced from the rate constant ( k ) of the studied bacterium (in log phase) and the half inhibitory concentration (IC 50 ), the experimental results reveal that the studied selenomorpholine compounds all have good antibiotic activity and better antibacterial activity on Staphylococcus aureus than on Escherichia coli.
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