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T. Mill

Publications and source records attributed to T. Mill.

2 recordsLinked to original sources
USGS2002

Reduction of CO2 to C1 products and fuel

Photochemical semiconductor processes readily reduced CO2 to a broad range of C1 products. However the intrinsic and solar efficiencies for the processes were low. Improved quantum efficiencies could be realized utilizing quantum-sized particles, but at the expense of using less of the visible solar spectrum. Conversely, semiconductors with small bandgaps used more of the visible solar spectrum at the expense of quantum efficiency. Thermal reduction of CO2 with Fe(II) was thermodynamically favored for forming many kinds of organic compounds and occurred readily with olivine and other Fe(II) minerals above 200??C to form higher alkanes and alkenes. No added hydrogen was required.

Conference Paper↗
USGS1997

Fate and transport of metam spill in Sacramento River

A mass balance model was developed and applied to the Sacramento River in northern California during the July 1991 Sacramento River metam-sodium spill. The transport and reactions of metam-sodium, a soil fumigant, and the volatile and toxic methyl isothiocyanate (MITC) were simulated during the two-and-a-half days of movement along a 68-km stretch of river. Results from modeling were compared with field data for MITC, which is the only product measured downriver after the spill. Agreement between the simulated and measured values of MITC concentrations were found at Doney Creek (65.9 km downstream). Results illuminated the complexities and unique characteristics associated with the multiple kinetic processes of the chemical plume in the river. In particular, the photolysis of metam-sodium followed zero-order kinetics for high concentrations and first-order kinetics for low concentrations, a unique phenomenon consistent with the finding reported in a laboratory study. Concentrations of metam-sodium for transition from zeroto first-order, obtained by calibration and model sensitivity analyses, were in the same range as those in the reported laboratory results.

Journal of Environmental Engineering↗