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A moisture-sensitive diisocyanate liquid is microencapsulated within a metal shell measuring less than 2 μm thick and 50 μm in diameter. This mild synthesis takes place through a series aqueous processing steps that occur at or near room temperature. Through a combination of emulsification, interfacial polymerization, and electroless plating, one can microencapsulate moisture- or air-sensitive chemicals within a metal seal. The liquid-filled metal microcapsules promise a number of advantages compared to conventional polymeric microencapsulation, including improved mechanical properties and improved barrier properties to gases and organic molecules.

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a b s t r a c tUnder various conditions, chromium carbides appear to be relatively stable in the presence of molten fluoride salts and this suggests that their use in corrosion resistant coatings for fluoride salt environments could be beneficial. One method for producing these coatings is the carburization of sprayed Cr coatings using methane-containing gaseous precursors. This process has been investigated for the synthesis of binder-free chromium carbide coatings on nickel-based alloy substrates for molten fluoride salt corrosion resistance. The effects of the carburization process on coating microstructure have been characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM) in conjunction with energy dispersive spectroscopy (EDS). Both plasma-sprayed and cold-sprayed Cr coatings have been successfully converted to Cr 3 C 2 , with the mechanism of conversion being strongly influenced by the initial porosity in the as-deposited coatings.

The thermal transport properties were studied for carbons produced by the carbonization of microcrystalline cellulose. Thermal diffusivity, specific heat, and thermal conductivity were measured via flash method for cellulose derived carbons prepared at various heat treatment temperatures ranging from 250°C to 1000°C. The thermal diffusivity as a function of increasing heat treatment temperature was observed to have four distinct linear regions, which could be related directly to the microstructures of the materials generated by the specific heat treatment temperature. Specific heat values indicated the coexistence of polar and non-polar phases in both partially carbonized materials obtained at lower heat treatment temperatures and fully carbonized materials formed at higher heat treatment temperatures. For partially carbonized materials, the polar groups consisting of residual hydroxyl and carboxyl were still present. For fully carbonized materials, the polar phases have largely been volatilized and conductive nano-carbon clusters were nucleated and observed to grow in an amorphous carbon bed until percolation effects were observed. Such structural characteristics are well supported by FT-IR characterizations. Lastly, a linear relationship between testing temperature and thermal conductivity indicates boundary scattering between highly conductive carbon clusters as the main mechanism for heat conduction.