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Full-Text Articles in Chemistry
Complex Fluid Dynamics: Chemo-Hydrodynamics Driven By Autocatalytic Reaction Fronts, Matthew Walter Eskew
Complex Fluid Dynamics: Chemo-Hydrodynamics Driven By Autocatalytic Reaction Fronts, Matthew Walter Eskew
Dissertations and Theses
Chemo-hydrodynamics generated from reaction-diffusion-convection processes of autocatalytic chemical systems are extensively studied for their applications in modeling complex systems. Compared to the more extensively studied autocatalytic systems, chlorite-tetrathionate and chlorite-trithionate, the chlorite-thiourea systems is relatively unexplored. Compared to the two previous systems, chlorite-thiourea has more straightforward chemical kinetics. To narrow the gap between chlorite-thiourea and the other systems a combination of experimental study and numerical simulation were employed to quantify this system.
Compared to established literature, experiments were performed at five orders of magnitude lower concentration of indicator, minimizing confounding effects of indicator on hydrodynamic motion. To accurately image the …
Investigation Of The Sources And Sinks Of Atmospheric Methane, Christopher Lee Butenhoff
Investigation Of The Sources And Sinks Of Atmospheric Methane, Christopher Lee Butenhoff
Dissertations and Theses
The work presented here represents a number of independent studies that investigated various components of the CH4 budget, namely the sources and sinks. We used a chemical-tracer model and created unique long-term time series of atmospheric CH4, carbon monoxide (CO), molecular hydrogen (H2), and methylchloroform (CH3CCl3) measurements at marine background air to derive histories of atmospheric hydroxyl radical (OH) - the main chemical oxidant of CH4, biomass burning - an important source of CH4 in the tropics, and emissions of CH4 from rice paddies - one of …
Evidence For The Existence Of Two Stable Sites For Cobalt Impurity Atoms In Aluminum, Arun Venkatachar
Evidence For The Existence Of Two Stable Sites For Cobalt Impurity Atoms In Aluminum, Arun Venkatachar
Dissertations and Theses
Using Fe57Mössbauer spectroscopy, two alternative sites occupied by cobalt (10-4 at. % ) impurity atoms in aluminum have been isolated. The substitutional site A is the stable position after annealing the sample above 840 K, followed by a rapid quench. The impurity atoms in site A are characterized by a single line Mössbauer spectrum (indicative of a cubic environment), a room-temperature f = 0.502 (r. m. s. displ. 0.071 A) and an I. S. (reI. to Fe) = -0.421 mm/sec. For anneals below 770 K the cobalt atoms migrate to site B, which is characterized by a …
Investigation Of The Alpha-Sub-Gamma Phase In Alnico 6, Cortez Samuel
Investigation Of The Alpha-Sub-Gamma Phase In Alnico 6, Cortez Samuel
Dissertations and Theses
The purpose of this research project was to study the αᵧ phase in Alnico 6. Other phases were studies for comparison. Also the effect of an applied magnetic field on the formation of the αᵧ phase was investigated.
Three single crystals of Alnico 6 were heat treated for one hour—one at 1250°C, one at 1000°C, and one at 800°C—and water-quenched. The microstructure of each sample was observed with the optical microscope, and X-ray diffraction patterns were taken to determine the crystal structure of the phases present.
Several single crystal samples of Alnico 6 were heat treated at 1000°C and furnace-cooled. …