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  1. Method of CO and/or CO.sub.2 hydrogenation to higher hydrocarbons using doped mixed-metal oxides

    A method of hydrogenation utilizing a reactant gas mixture comprising a carbon oxide and a hydrogen agent, and a hydrogenation catalyst comprising a mixed-metal oxide containing metal sites supported and/or incorporated into the lattice. The mixed-metal oxide comprises a pyrochlore, a brownmillerite, or mixtures thereof doped at the A-site or the B-site. The metal site may comprise a deposited metal, where the deposited metal is a transition metal, an alkali metal, an alkaline earth metal, or mixtures thereof. Contact between the carbon oxide, hydrogen agent, and hydrogenation catalyst under appropriate conditions of temperature, pressure and gas flow rate generate amore » hydrogenation reaction and produce a hydrogenated product made up of carbon from the carbon oxide and some portion of the hydrogen agent. The carbon oxide may be CO, CO.sub.2, or mixtures thereof and the hydrogen agent may be H.sub.2. In a particular embodiment, the hydrogenated product comprises olefins, paraffins, or mixtures thereof.« less
  2. Microwave-assisted pyrolysis of Mississippi coal: A comparative study with conventional pyrolysis

    Pyrolysis conditions greatly affect the structure-reactivity relationship of char during coal gasification. Here, this work investigated the effect of temperature and microwave heating on the structural properties of the chars generated during pyrolysis, as well as gaseous and tar products. Results showed that microwave pyrolysis of Mississippi coal produced more gaseous products and less tars compared to conventional pyrolysis. Higher CO/CO 2 ratio (>1) was observed under microwave pyrolysis compared to conventional pyrolysis (CO/CO2 < 1), which may be explained by a greater extent of gasification between solid carbon and the CO 2 formed during microwave pyrolysis. Additionally, in microwavemore » pyrolysis, the oil tars generated exhibited lower concentrations of polar oxygenates, while the wax tars showed higher concentrations of non-polar alkanes, as observed from the intensity of CH vibrations in FTIR. The product compositions and FTIR analysis of the tars (oils and waxes) suggest that the microwave interacted preferentially with these polar species, which have relatively higher dielectric properties compared to alkanes. The structure–reactivity relationship of the chars produced was also investigated using a variety of characterization tools such as XRD, BET, SEM, EDS, and FTIR. Finally, the char reactivity towards combustion suggested that microwave-produced chars have a higher thermal stability, likely due to lower O/C ratios, and could be utilized in the metallurgical industry.« less
  3. Multi-mode Observations of Cloud-to-Ground Lightning Strokes.

    Abstract not provided.
  4. PD UITI poster.

    Abstract not provided.
  5. Method of CO and/or CO.sub.2 hydrogenation using doped mixed-metal oxides

    A method of hydrogenation utilizing a reactant gas mixture comprising a carbon oxide and a hydrogen agent, and a hydrogenation catalyst comprising a mixed-metal oxide containing metal sites supported and/or incorporated into the lattice. The mixed-metal oxide comprises a perovskite, a pyrochlore, a fluorite, a brownmillerite, or mixtures thereof doped at the A-site or the B-site. The metal site may comprise a deposited metal, where the deposited metal is a transition metal, an alkali metal, an alkaline earth metal, or mixtures thereof. Contact between the carbon oxide, hydrogen agent, and hydrogenation catalyst under appropriate conditions of temperature, pressure and gasmore » flow rate generate a hydrogenation reaction and produce a hydrogenated product made up of carbon from the carbon oxide and some portion of the hydrogen agent. The carbon oxide may be CO, CO.sub.2, or mixtures thereof and the hydrogen agent may be H.sub.2. In a particular embodiment, the hydrogenated product comprises an alcohol, an olefin, an aldehyde, a ketone, an ester, an oxo-product, or mixtures thereof.« less
  6. Method for continuous synthesis of metal oxide powders

    A method for the rapid and continuous production of crystalline mixed-metal oxides from a precursor solution comprised of a polymerizing agent, chelated metal ions, and a solvent. The method discharges solution droplets of less than 500 .mu.m diameter using an atomizing or spray-type process into a reactor having multiple temperature zones. Rapid evaporation occurs in a first zone, followed by mixed-metal organic foam formation in a second zone, followed by amorphous and partially crystalline oxide precursor formation in a third zone, followed by formation of the substantially crystalline mixed-metal oxide in a fourth zone. The method operates in a continuousmore » rather than batch manner and the use of small droplets as the starting material for the temperature-based process allows relatively high temperature processing. In a particular embodiment, the first zone operates at 100-300.degree. C., the second zone operates at 300-700.degree. C., and the third operates at 700-1000.degree. C., and fourth zone operates at at least 700.degree. C. The resulting crystalline mixed-metal oxides display a high degree of crystallinity and sphericity with typical diameters on the order of 50 .mu.m or less.« less
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"Smith, Mark W."

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