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TECHNOLOGY MATURATION OF DISPERSION TECHNOLOGY TO AUGMENT BIOREMEDIATION

Description: The data obtained from this preliminary short-term project demonstrated that dispersants such as 54GO are effective in accelerating the bio-remediation of soils containing contamination from waste oils, diesel, creosote and manufactured gas plant waste. This acceleration appears to be in the observation that 54GO quickly separates the hydrocarbon wastes from the soil particles, thereby allowing closer contact with the microbes. The project time limitations impacted the scope of data but was able to demonstrate a general reduction in the levels of contaminates. In this project only Total Petroleum Hydrocarbons [TPH] and 17 polycyclic aromatic hydrocarbons [PAH] were analyzed. These were chosen because they are standardized by EPA methodology. The raw data from these analytical methods indicate that there are many more intermediate metabolizes from the bio-remediation process that were not identified or measured [a limitation of the 17 analyte EPA Method 8270 protocol]. The limited data from these bio-reactors indicates that when both 54GO [dispersant] and stress selected microbes are used the reduction of contaminate metabolizes is the greatest. The use of microbes alone was also effective, but not consistent and to a lesser degree. An additional observation with 54GO, either alone or with microbes is that significant amounts of hydrocarbons were extracted or released from the test soils and became a separate phase floating on the surface of these bio-reactors. The levels of floating oil in these bio-reactors made mixing and sampling difficult tasks. This latter effect of, 54GO, indicates that this family of dispersants are excellent candidates for classic soil washing techniques and may be better served by pre-treating waste soils before mixing with microbes. It is estimated that 75% or more of the hydrocarbons were in the oil phase in these bio-reactors even in low water conditions [saturated soil].
Date: July 1, 2000
Creator: 54GO, J. NEELY -
Partner: UNT Libraries Government Documents Department

THERMAL STABILITY AND MECHANICAL BEHAVIOR OF ULTRA-FINE BCC TA AND V COATINGS

Description: Ultra-refined microstructures of both tantalum (Ta) and vanadium (V) are produced using electron-beam evaporation and magnetron sputtering deposition. The thermal stability of the micron-to-submicron grain size foils is examined to quantify the kinetics and activation energy of diffusion, as well as identify the temperature transition in dominant mechanism from grain boundary to lattice diffusion. The activation energies for boundary diffusion in Ta and V determined from grain growth are 0.3 and 0.2 eV{center_dot}atom{sup -1}, respectively, versus lattice diffusion values of 4.3 and 3.2 eV{center_dot}atom{sup -1}, respectively. The mechanical behavior, as characterized by strength and hardness, is found to inversely scale with square-root grain size according to the Hall-Petch relationship. The strength of Ta and V increases two-fold from 400 MPa, as the grain size decreases from 2 to 0.75 {micro}m.
Date: November 3, 2006
Creator: Jankowski, A F; Go, J & Hayes, J P
Partner: UNT Libraries Government Documents Department

Energy randomisation. How much of rotational phase space is explored? How long does it take?

Description: In applying modern theories (RRKM) of unimolecular reaction, it is necessary to decide the volume of phase space in which the energy is assumed to be randomized. The question of whether the K rotational quantum number is conserved impacts on that choice. The conceptual sequence from experimental spectra, through analysis, and interpretation in terms of K relaxation is described for ethanol and 1-butyne in the 3 micron region. The interpretation of molecular eigenstate spectra involves identification of the bright state from the coherent excitation of part of the spectrum, evaluation of the rate of energy transfer out of the bright state, deducing the mechanism of the coupling of the bright state to the bath states, and modeling the spectra in order to determine the average coupling parameters for anharmonic coupling and Coriolis interactions.
Date: December 1995
Creator: Perry, D. S.; Bethardy, G. A.; Davis, M. J. & Go, J.
Partner: UNT Libraries Government Documents Department