Raw Mg,Si powder were used to fabricate Mg2Si bulk thermoelectric generator by spark plasma sintering （SPS）.The optimum parameters to synthesize pure Mg2Si powder were found to be 823 K,0 MPa,10 min with excessive c...
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Raw Mg,Si powder were used to fabricate Mg2Si bulk thermoelectric generator by spark plasma sintering （SPS）.The optimum parameters to synthesize pure Mg2Si powder were found to be 823 K,0 MPa,10 min with excessive content of 10wt% Mg from the stoichiometric ***2Si bulk was synthesized and densified simultaneously at low temperature （823 K） and high pressure （higher than 100 MPa） from the raw powder,but Mg,Si could not react completely,and the sample was not very dense with some microcracks on the ***,Mg,Si powder reacted at 823 K,0 MPa,10 min in SPS chamber to form Mg2Si green compact,again sintered by SPS at 1023 K,20 MPa,5 *** fabricated sample only contained Mg2Si phase with fully relative density.
Iridium thin films have been deposited on Si3N4（100 nm）/Si（100） substrates by magnetron sputtering. And then iridium film micro-patterns were fabricated by ion milling technique. The atomic force microscopy （AFM...
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Iridium thin films have been deposited on Si3N4（100 nm）/Si（100） substrates by magnetron sputtering. And then iridium film micro-patterns were fabricated by ion milling technique. The atomic force microscopy （AFM） measurements reveal that there is a very fiat and smooth surface with an average roughness of 0.64 nm for the iridium films. The X-ray diffraction also reveals that the deposited iridium films have a polycrystalline microstructure with （111） plane preferential orientation. The electrical resistivity of the iridium films was also measured and discussed.
Skutterudite CoAs3 is a potentially important thermoelectric material. Morse potential is employed here to carry out molecular dynamics simulations of nanobulk CoAs3 at the temperature of 0 K. The stress-strain relati...
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Skutterudite CoAs3 is a potentially important thermoelectric material. Morse potential is employed here to carry out molecular dynamics simulations of nanobulk CoAs3 at the temperature of 0 K. The stress-strain relationships under uniaxial tensile and/or compressive strain are obtained. The elastic modulus, extreme strength and deformation mechanism are studied. The simulation results indicate that nanobulk CoAs3 abruptly ruptures at much higher strain level under tension than conventional bulk CoAs3. Both the extreme stresses under tension and compression are much higher than those of conventional bulk CoAs3.
A series of samples of hexagonal boron nitride-aluminum nitride ceramic composites with different amounts of CaF2 as sintering aid were prepared by spark plasma sintered at 1700-1850 ℃ for 5 *** addition of CaF2 effe...
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A series of samples of hexagonal boron nitride-aluminum nitride ceramic composites with different amounts of CaF2 as sintering aid were prepared by spark plasma sintered at 1700-1850 ℃ for 5 *** addition of CaF2 effectively lowered the sintering temperature and promoted the densification of AlN-BN *** the increase of sintering temperature,the density increased,and the contiguity of AlN grains enhanced in AlN-BN *** conductivity of AlN-BN composites increased with the increase in CaF2 content and sintering temperature,and there is a maximum value of 78.6 W·m^-1·K^-1 when the sample with 3wt% CaF2 sintered at 1800 ℃.
ZnO hexagonal prism crystals were synthesized from ZnO powders by microwave heating in a short time （within 20 min） without any metal catalyst or transport agent. Zinc oxide raw materials were made by evaporating fr...
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ZnO hexagonal prism crystals were synthesized from ZnO powders by microwave heating in a short time （within 20 min） without any metal catalyst or transport agent. Zinc oxide raw materials were made by evaporating from the high-temperature zone in an enclosure atmosphere and crystals were grown on the self-source substrate. The inherent asymmetry in microwave heating provides the temperature gradient for crystal growth. Substrate and temperature distribution in the oven show significant effects on the growth of the ZnO crystal. The morphologies demonstrate that these samples are pure hexagonal prism crystals with maximum 80 lain in diameter and 600 lure in length, which possess a well faceted end and side surface. X-ray diffraction （XRD） reveals that these samples are pure crystals. The photoluminescence （PL） exhibits strong ultraviolet emission at room temperature, indicating potential applications for short-wave light-emitting photonic devices.
Electroless CoNiWP magnetic films were prepared by varying the bath pH and then characterized by energy dispersive X-ray analysis, X-ray diffraction and magnetic force microscopy, it has been found that the microstruc...
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Electroless CoNiWP magnetic films were prepared by varying the bath pH and then characterized by energy dispersive X-ray analysis, X-ray diffraction and magnetic force microscopy, it has been found that the microstructure and the magnetic properties of films were influenced greatly by the bath pH. At the bath pH 8.06, the grain size and coercivity of the films reach maximuml while the squareness （Mr/Ms） of MH curves reaches minimum. The Henkel plots indicates that the exchange-coupling interaction is very weak at this pH, which may be caused by phase-separation and large grain size, and then results in the lowest squareness. At pH above 8.5, obvious exchange-coupling interaction is observed because of the inexistence of phase-separation and the refinement of grain size.
ITO/AZO double films were deposited by RF sputtering on p-Si texturized substrate to fabricate ITO/AZO/SiO 2 /p-Si SIS heterojunction. The structural, optics and electrical properties of the ITO/AZO films were charact...
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ITO/AZO double films were deposited by RF sputtering on p-Si texturized substrate to fabricate ITO/AZO/SiO 2 /p-Si SIS heterojunction. The structural, optics and electrical properties of the ITO/AZO films were characterized by UV-VIS spectrophotometer, four point probe, respectively. The results show that ITO/AZO films have good quality. The electrical junction properties were investigated by I-V measurement, which reveals that the heterojunction shows typical good rectifying behavior and great photoelectric effect.
The structural change in phase transition of hybrid(C12H25NH3)2MnCl4 was *** temperature and the structures of the phase transition is investigated by thermal gravimetry(TG)and differential scanning calorimetry(DSC),i...
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The structural change in phase transition of hybrid(C12H25NH3)2MnCl4 was *** temperature and the structures of the phase transition is investigated by thermal gravimetry(TG)and differential scanning calorimetry(DSC),infrared spectrum(IR)and X-ray diffraction(XRD).The results suggest that the phase transition is reversible and the structural change arises from the conformation change of the organic *** interlayer distance increases when the hybrid transforms from low temperature phase to high temperature *** is explained by the diffusion of gauche-bond along the organic chains and they move away from each other when the phase transition *** the experimental data with theoretical calculation,we propose that organic chain of the hybrid in high temperature phase is the conformation of gauche-bond alternating with trans bond(noted as GTG'TGTG'TGTG'T).
A theoretical model based on BCT lattice structure was developed. Resultant force in the BCT lattice structure was deduced, following the interaction force of two kinds of magnetic particles. According to empirical Fr...
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A theoretical model based on BCT lattice structure was developed. Resultant force in the BCT lattice structure was deduced, following the interaction force of two kinds of magnetic particles. According to empirical FroHlich-Kermelly law, the relationship between the magnetic induction and the magnetic field was discussed, and a predictive formula of shear stresses of the BCT lattice structure model was established for the case of small shear deformation. Compared with the experimental data for different particle volume fractions, the theoretical results of the shear stress indicate the effects of the saturation magnetization and the external magnetic field on the shear stress.
Surface-attached micropattemed polyelectrolyte brushes on planar solid surfaces are generated using free radical polymerization photo-initiated by self-assembled initiator monolayers. It is shown that the formed patte...
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Surface-attached micropattemed polyelectrolyte brushes on planar solid surfaces are generated using free radical polymerization photo-initiated by self-assembled initiator monolayers. It is shown that the formed patterns can be either negative or positive with different patterning processes.
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