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The carbon forms made from sucrose and microcapsules have successfully fabricated using gel-casting method. The structure, density, compressive strength and thermal conductivity were characterized. Carbon foams have porous structure of open cells and closed cells. The density of carbon foams is regulated in the range of 0.29-0.65 g/cm3, whereas the compressive strength is in the range of 1.03-20.25 MPa. The thermal conductivity at room temperature of carbon foams can be as low as 0.11 W/m·K. Therefore, these carbon foams have potential for use as the thermal insulator. [ABSTRACT FROM AUTHOR]

The hollow spherical nano-TiO2 was successfully synthesized by carbon spheres as the template and Ti-bearing blast furnace slag as the Ti source. The SEM and TEM results showed that the as-synthesized TiO2 consist of uniform separated hollow spheres, and the sphere wall was composed of nanoparticles. The XRD result showed that the crystallized phase was rutile. Almost complete extraction of Ti from slag was achieved in NaOH-NaF molten salt. The kinetic analysis indicated that the slag decomposition was applied to control of chemical reaction of the reactionless core-shrinking model, and the apparent activation energy was39.54 kJ mol-1. [ABSTRACT FROM AUTHOR]

A disordered Nd:SrGdGa3O7 (Nd:SGGM) laser crystal was grown by the Czochralski method. The space group and effective segregation coefficient of Nd3+ were determined to be P421m and 1.36, respectively. Thermal properties, including the average linear thermal expansion coefficient, thermal diffusivity, specific heat, and thermal conductivity were measured. It was found that the thermal conductivity increases with increasing temperature, indicating glasslike behavior. Sellmeier's equations were fitted by measuring the refractive indices in the range of 253-2325 nm. The polarization absorption and emission spectra were measured at room temperature, and Judd-Ofelt analysis was carried out to calculate the fluorescence branching ratios from the upper 4F3/2 state and the fluorescence lifetime. The stimulated emission cross section for the 4F3/2→4I11/2 transition was calculated to be 2.00×10-20 cm2. Finally, a diode-pumped laser experiment at 1.06 μm is described. Thermal, optical, and laser properties have shown that Nd:SGGM crystals are promising for use as disordered laser materials. [ABSTRACT FROM AUTHOR]

A series of laser crystals Nd:LuxGd1-xVO4 (x=0.14,0.32,0.50,0.61,0.70,0.80) was grown by the Czochralski method. The thermal properties, including the average linear thermal expansion coefficients, thermal diffusion coefficients, specific heats, and thermal conductivities, of the mixed crystals were obtained. The material constants Ms for the thermal stress resistance figure were calculated and showed that the thermal fracture limits of the mixed crystals should be comparable with that of Nd:YVO4. The polarization absorption spectra from 240 to 1000 nm were measured at room temperature and the absorption cross sections at 809 nm were calculated. Using the Judd-Ofelt theory, the theoretical radiative lifetimes were calculated and compared with the experimental results. Continuous wave laser performances were achieved with the mixed crystals at the wavelength of 1.06 μm when they were pumped by a laser diode. Thermal, optical, and laser properties have shown variation as a function of x and proved that the mixed crystals are good laser materials. [ABSTRACT FROM AUTHOR]

Presents information on a study which described a linear perturbation analysis for a three-dimensional solid surface evolving under stress using a general kinetic law. Information on kinetic laws; Linear perturbation analysis; Surface profile spectra; Conclusions.