In situ preparation of silver nano-particles in polymethylmethacrylate (PMMA) using N, N-dimethylformamide (DMF) as a medium has been performed successfully. Nano-Ag/PMMA composite film was characterized by X-ray diff...
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In situ preparation of silver nano-particles in polymethylmethacrylate (PMMA) using N, N-dimethylformamide (DMF) as a medium has been performed successfully. Nano-Ag/PMMA composite film was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), UV-Vis absorption spectrum (UV-Vis). The results showed that: the sample exhibits a typical face-centered cubic(fcc) silver phase, and with the reaction time increasing, the nano-silver particles sizes increased gradually, by the shaps changed spherical into nanoprisms. In the composition film, there was a certain mutual chemical reaction between the nano-silver particles and the PMMA martix, which lead to the nano-silver particles existenced in PMMA matrix stably and distributedly, and the film obviously had optical absorption in UV-Vis for SPR(surface plasma resonance) of nano-sliver.
作者：
Pan YongJun潘勇军Xie HongQuan陈勇Chen Yong崔丽College of Material Science and Engineering
Wuhan Textile University Wuhan 430074 China 武汉纺织大学材料科学与工程学院 武汉 430073 Department of Chemistry Huazhong University of Science and Technology Wuhan 430074China 武汉理工大学复合材料国家重点实验室 武汉 430070 State key laboratory of advanced technology for materials synthesis and processingWuhan University of Technology Wuhan 430070 China
Catalytic effects of NiCl,TiC and TiN on the dehydrogenation/rehydrogenation characteristics of LiAlH were investigated by pressure -content-temperature(PCT),X-ray diffraction(XRD),differential scanning calorimatory(D...
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Catalytic effects of NiCl,TiC and TiN on the dehydrogenation/rehydrogenation characteristics of LiAlH were investigated by pressure -content-temperature(PCT),X-ray diffraction(XRD),differential scanning calorimatory(DSC),and field emission scanning electron microscopy(FESEM).The doped samples exhibit dehydrogenation at much lower *** with NiCl,TiC and TiN induce a decrease in the decomposition of first step by about 50-65℃compared to that of as received ***,amount of hydrogen release is significantly higher for TiC additions than that of samples doped with TiN and *** desorption results at 125℃reveal that dehydrating rate of doped alanate is much faster than that of pure ***,TiN and NiCl dopants show the reabsorption of about 1.9 wt.%, 1.3 wt.%,and 1.1 wt.%,*** and FESEM analyses suggest that both TiC and TiN are stable during the ball milling as well as the dehydrogenation *** the contrary,NiCl reacts and causes the partial decomposition of Li alanate during the ball milling process.
Hyperbranched poly(urea-urethane)-grafted multi-walled carbon nanotubes (HPU-MWCNTs) were incorporated in a polyurethane (PU) matrix based on poly(ethylene oxide-tetrahydrofuran) and aliphatic polyisocyanate resin as ...
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In present paper a new niobate materials Ba5LixTixNb10-xO30 were synthesized by doping Li+ in the system BaO- TiO2- Nb2O5 in millimeter wave field. X-ray diffraction (XRD) quantitative and scanning transition spectros...
In present paper a new niobate materials Ba5LixTixNb10-xO30 were synthesized by doping Li+ in the system BaO- TiO2- Nb2O5 in millimeter wave field. X-ray diffraction (XRD) quantitative and scanning transition spectroscopy (SEM) analysis were employed to study crystal structure and microstructure of reaction products. It was found that pure products could be obtained at temperature 900°, 8 min which is lower comparing with that by conventional method. The XRD data shown the crystal belongs to tetragonal tungsten bronze structure with space group P4bm. The grain size synthesized in millimeter wave field had smaller size, narrower distribution, better sinter-ability, and without hard agglomeration comparing whit that obtaining from conventional synthesis. At lower temperature Ba5LiTiNb9O30 is a tetragonal ferroelectric phase.
A high performance thermosetting epoxy resin crosslinkable at room temperature was obtained via directly moulding diglycidyl ether of bisphenol A（DGEBA） and flexibleα,ω-bisamino（n-alkylene）phenyl terminated poly...
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A high performance thermosetting epoxy resin crosslinkable at room temperature was obtained via directly moulding diglycidyl ether of bisphenol A（DGEBA） and flexibleα,ω-bisamino（n-alkylene）phenyl terminated poly（ethylene glycol）.The influences of the n-alkylene inserted in aminophenyl of flexible amino-terminated polythers（ATPE） on the mechanical properties,fractographs and curing kinetics of the ATPE-DGEBA cured products were *** results show that the insertion of n-alkylene group into the aminophenyl group of the ATPE,on one hand,can significantly increase the strain relaxation rate and decrease glass transition temperature of the ATPE-DGEBA cured products,resulting in slight decrease of the Young’s modulus and tensile strength,and significant increase of the toughness and elongation of the ATPE-DGEBA cured *** the other hand,it can remarkably enhance the reactivity of amine with epoxy,much accelerating the curing rate of the ATPE-DGEBA *** activation energy of DGEBA cured by BAPTPE,BAMPTPE and BAEPTPE was 53.1,28.5 and 25.4 kJ·mol;,*** as-obtained ATPE-DGEBA cured products are homogeneous, transparent,and show excellent mechanical properties including tensile strength and *** they are promising to have important applications in structure adhesives,casting bulk materials,functional coatings,cryogenic engineering, damping and sound absorbing materials.
Single-phase skutterudite compounds with highly relative density Ce0.8Fe4-x NixSb12(x=0-0.15) were prepared by combining melt spinning technique with spark plasma sintering. Their phase structure, microstructure and t...
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Single-phase skutterudite compounds with highly relative density Ce0.8Fe4-x NixSb12(x=0-0.15) were prepared by combining melt spinning technique with spark plasma sintering. Their phase structure, microstructure and thermoelectric properties were investigated. The result reveals that all samples show p-type conduction. When Fe was substituted by Ni, the electrical properties can be reduced to some extent, but the total thermal conductivity is decreased more evidently due to the reduction of κe caused by decreased carrier concentration and κL caused by alloying scattering. The maximum ZT value of about 0.73 is obtained at 800 K for the x=0.05 and x=0.10 samples, which was 18% higher than that of x=0 sample.
ZnO sub-millimeter crystals were synthesized by microwave heating from ZnO powders without any catalyst or transport agent. Zinc oxide raw materials were evaporated from the high-temperature zone in an enclosure and c...
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ZnO sub-millimeter crystals were synthesized by microwave heating from ZnO powders without any catalyst or transport agent. Zinc oxide raw materials were evaporated from the high-temperature zone in an enclosure and crystals were grown on the self-source substrate. The thermodynamics analysis method was used to estimate the partial pressure of gases in the chamber, which shows that the pressure of ZnO could be neglected entirely in the range of experiment temperature. The kinetics analysis was employed to estimate the growth rate in different conditions, which shows a remarkable temperature gradient and a high system temperature would enhance the growth rate. Optics photos reveal that these products are hexagon crystals with 0.2-0.3 mm in diameter and 0.5-1 mm in length. A vapor-solid mechanism is proposed to explain the growth process of ZnO crystals. The temperature distribution in microwave oven is mainly determined by properties of electric field and it is different from that of a conventional method.
Fe doped In2O3 samples （In1-xFex）2O3 （x=0, 0.05, 0.1, 0.2 and 0.3） on glass substrate were prepared by sol-gel method. The XRD results demonstrate that the solubility of Fe ions in In2O3 matrix is around 20%, abov...
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Fe doped In2O3 samples （In1-xFex）2O3 （x=0, 0.05, 0.1, 0.2 and 0.3） on glass substrate were prepared by sol-gel method. The XRD results demonstrate that the solubility of Fe ions in In2O3 matrix is around 20%, above which impurity phase can be observed. The transmittance of the samples with x=0, 0.05, 0.1 and 0.2 are above 80% in the visible region while the transimittance of the glass is 90%. The transmittance curves slightly red-shifts as x increasing. All of the samples except x=0 are ferromagnetic at room temperature. The highest saturation magnetization moment is reached in the sample x=0.2 with 330 emu/cm3, and the coercive force is 169 Oe which is also the largest in our samples. The results indicate that the addition of Fe ions could tune the structure, the ferromagnetism and optical property in the In2O3 matrix.
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