The use of strained-layer superlattice is a well-established technique to lower Auger recombination in the active layer of mid-IR LEDs and laser. We have shown by temperature-dependent photoluminescence experiments the Auger recombination can be further reduced by incorporating InAs spacer layer inside symmetrically-strained InAsSb/InAlAs superlatt...
In the present work, the catalyst Pt was evaporated onto the sol-gel WO3, WO3-SiO2 films. These films were annealed at different temperatures and their structures were characterized by infrared, visible near infrared spectroscopy and X-ray diffraction. The coloring kinetics of the films was evaluated. The results revealed that the 0.75WO(3)-0.25SiO...
Amorphous WO3 gasochromic films have been prepared by the sol-gel method using tungsten and H2O2 as main materials. The structure and the properties of the films are investigated. The results show that the amorphous WO3 films prepared by this method have good gasochromic properties. WO, thin films are annealed in ambient air at a temperature of 250...
The adsorption of N-oleoylsarcosine onto in water dispersed magnetite nanoparticles were investigated at different concentrations and pH values. The coated nanoparticles surface became hydrophobic at a molar ratio of N-oleoylsarcosine:Fe3O4 below 0.22:1 within a pH range of 5-9.5. Aqueous-based magnetic fluids could not be obtained. A hydrophilic s...
The adsorption process of different dextran molecules onto the surface of in water dispersed magnetite nanoparticles has been investigated to optimize the preparation of magnetite magnetic fluids (MMFs). An average magnetite core size of 7.1 nm was found by X-ray diffraction and that of 8 nm was found by transmission electron microscopy for the sam...
In this paper, about 30 mu m thick B-doped polycrystalline silicon (poly-Si) thin films were deposited on quartz substrates, n-type single crystalline silicon wafers and p(++)-type poly-Si ribbons by a rapid thermal chemical vapour deposition system in a temperature range from 1000 to 1150 degrees C. Activation energy measurement and room temperatu...
The adsorption of alginate (Alg) onto the surface of in water dispersed Fe3O4 nanoparticles and zeta potential of alginate-coated Fe3O4 nanoparticles have been investigated to optimize the colloidal stability of Alg-coated Fe3O4 nanoparticles. The adsorption amount of Alg increased with the decrease of adsorption pH. The zeta potential of Fe3O4 nan...
We have observed oscillations in the low temperature (T
Gamma-Al2O3 nano-particles were synthesized and modified using gum arabic (GA) to avoid agglomeration in aqueous solutions. Its effect on adsorptive desulfurization and biodesulfurization was also evaluated. Results showed that gamma-Al2O3 nano-particles dispersed well in aqueous solutions after GA modification. The adsorptive desulfurization capac...
Anatase TiO2 films were successfully synthesized by a modified sol-gel method wherein peroxo titanic acid solution was derived from TiCl4/ethanol/water solution at room temperature. The as-prepared films were further surface-doped by photodeposited Fe2O3 and Cr2O3 to improve its physicochernical properties. The phase and structure of the films were...
