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.
Nanocrystalline titanium dioxide powder was synthesized by in-flight oxidation of titanium dihydride （TiH2） powder in a thermal plasma jet. TiH2 powder was injected into the thermal plasma jet and allowed to react w...
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Nanocrystalline titanium dioxide powder was synthesized by in-flight oxidation of titanium dihydride （TiH2） powder in a thermal plasma jet. TiH2 powder was injected into the thermal plasma jet and allowed to react with oxygen injected downstream the jet. Characteriza- tion of the powder by various analytical tools indicated that the powder consisted of nano-sized titanium dioxide particles consisting predominantly of the anatase phase. It is suggested that the thermo-chemistry of the oxidation process contributes significantly to the formation of nano-sized titania. The large energy released during the oxidation process dissociates the TiO2 particles into TiO（g） and titanium vapour, which recombine downstream with oxygen and form nano particles of TiO2.
In the present study, (1-x)(Sr_(0.88)Bi_(0.08))TiO_(3)-xBi(Mg_(0.5)Ti_(0.5))O_(3) (SBT-BMT) system was synthesized using conventional solid state processing. X-ray diffraction (XRD) and SEM testings were employed to d...
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ISBN:
(纸本)9781457711626
In the present study, (1-x)(Sr_(0.88)Bi_(0.08))TiO_(3)-xBi(Mg_(0.5)Ti_(0.5))O_(3) (SBT-BMT) system was synthesized using conventional solid state processing. X-ray diffraction (XRD) and SEM testings were employed to determine the phase constitution and microstructure of ceramics. SBT-BMT ceramics exhibited moderate dielectric permittivities ((epsilon)_(r)) (>1100 at RT) and low dielectric loss (0.07percent) over the temperature range from -20 to 200 deg C, with flat temperature coefficients of permittivity. In addition, SBT-BMT ceramics were observed to possess dielectric relaxation characteristics and energy densities, being on the order of 1.4 J/cm~(3) at 180 kV/cm was observed for the 0.8S_(0.88)B_(0.08)T-0.2BMT ceramics.
Morphotropic phase boundary (MPB) of (0.8-x)PMT-xPbTiO3(PT)-0. 2PbZrO3(PZ) ternary system (x = 0.4) was studied by X-ray diffraction (XRD). It shows that by comparing with 0.4PMT-0.2PZ-0.4PT sample, after doping with ...
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Morphotropic phase boundary (MPB) of (0.8-x)PMT-xPbTiO3(PT)-0. 2PbZrO3(PZ) ternary system (x = 0.4) was studied by X-ray diffraction (XRD). It shows that by comparing with 0.4PMT-0.2PZ-0.4PT sample, after doping with Ni, c/a remains almost same (about1.009), while both c and a decrease indicating that lattice shrinks. Content of the tetragonal phase TP% of Ni-doped samples increase up to 81.1% when the doping limit of the nickel is reached (y = 0.05), and the dielectric constant Ε was found to increase up to 4570 when y = 0.05 and the Curie temperatures of doping samples were found to decrease from 175°C to 157°C.
The relation among electronic structure, chemical bond and thermoelectric property of Ca3Co2O6 and Cu-doped is studied by first-principle theory. The results indicate that the highest valence band(HVB) and the lowest ...
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The MoxV3−xO7/MWNTs nanocomposites were fabricated via a hydrothermal reaction followed by self-assembling process. The nanocomposites were characterized in terms of surface morphology and structure by FESEM, TEM, XRD...
The MoxV3−xO7/MWNTs nanocomposites were fabricated via a hydrothermal reaction followed by self-assembling process. The nanocomposites were characterized in terms of surface morphology and structure by FESEM, TEM, XRD and XPS analysis, respectively. The electrochemical behaviors of the nanocomposites were investigated by galvanostatic charge-discharge test and cyclic voltammetry. The results showed that MoxV3−xO7/MWNTs nanocomposites had great cycleability as well as capacity characteristics, which was 277.4 mAh/g in the first discharge process and remained 207.9 mAh/g after fiftieth discharge cycle. In the rapid charge-discharge test, the capacity rate still remained 88.6 % after twentieth cycles at 1.2 C discharge.
1:1 under 1300°C, 30 MPa, held for 2 hour. Cyclic oxidation behavior of Ti2AlN was investigated 800°C, 900°C and 1000°C. The phase composition, thickness of oxidation layer and element content of s...
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1:1 under 1300°C, 30 MPa, held for 2 hour. Cyclic oxidation behavior of Ti2AlN was investigated 800°C, 900°C and 1000°C. The phase composition, thickness of oxidation layer and element content of samples were investigated by X-ray diffraction and scanning electron microscopy (SEM). The results show cyclic oxidation behavior of Ti2AlN generally obeys a parabolic law from 800°C, 900°C and 1000°C. The main phases in oxidation layer consists of TiO2 and α-Al2O3. When the temperature exceeds 800°C, the oxidation layer is easy to fall off because of a large compressive stress occurs in the oxidation scale. The oxidation behavior of Ti2AlN in air is poorer than those of Ti3 AlC2and Ti3 SiC2 material.
Flame-retardant mechanism of magnesium oxychloride （M OC） in EP was in-vestigated by limiting oxygen index （LOI）, XRD, SEM, TG-DTG and DSC. The results show that MOC performed well as an inorganic flame-retardant ...
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Flame-retardant mechanism of magnesium oxychloride （M OC） in EP was in-vestigated by limiting oxygen index （LOI）, XRD, SEM, TG-DTG and DSC. The results show that MOC performed well as an inorganic flame-retardant in EP. When the content of MOC is 50%, the LOI of EP reaches 29.6% and mass of residual char reaches 9.6%. The flame retarde mechanism of MOC is due to the synergies of diluting, cooling, catalyzing char forming and obstructing effects.
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