Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 10 of 10 for “"nitrogen flux"”.
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Carbon and nitrogen flux through the Cape rock lobster jasus lalandii (H. Milne Edwards), with particular reference to the nearshore Benguela system
… to 1986 to quantify the passage of carbon and nitrogen through populations at Oudekraal and Robben Island on the west coast of South Africa. The terms of the energy flow equation, C=P+R+G+UE+Ux+Uo+F (where C=consumption, P=production, R=respiration, G=reproduction, UE=Exuvial loss, Ux=excretion …
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Influences of Mountainside Residential Development to Nutrient Dynamics in a Stream Network
… input versus in-stream processes in modifying nitrogen export. I also conducted a simulation to investigate the impacts of housing density, buffer zone protection, and stream travel distance from the residential development to the catchment outlet on nitrogen export at the local and regional …
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Controlled delivery of nitric oxide for cytotoxicity studies
… solutions. It was found that the total flux of nitrogen species into the liquid was 40-90% greater in the presence of 02, depending on the NO partial pressure in the gas. Also, the simultaneously measured mass transfer coefficients for NO and 02 differed greatly from the corresponding …
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Factors Affecting Short-term Oxygen Variability in the Northern Gulf of Mexico Hypoxic Zone
… related to the monthly Mississippi River nitrogen flux. Using time-series analysis, I found no consistent periodicities in DO across the three depths (near-surface, mid-water-column, and near-bottom) or related to water levels (tides). I did find a diel signal in the DO that could be …
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Growth kinetics and doping of gallium nitride grown by rf-plasma assisted molecular beam epitaxy
… decomposition rates. Conditions producing a flux consisting predominantly of either atomic nitrogen or nitrogen metastables have been established using various rf-sources. Atomic nitrogen, possibly coupled with the presence of low energy ions, is associated with the premature decrease in …
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The relative role of protozoans in the flux of phytoplankton nitrogen through pelagic food webs
… upwelling region in April 1989 to budget the nitrogen flux through the different microplanktonic compartments leading to copepods. Uptake of nitrate and ammonium by three different size classes of phytoplankton (net-, nano-, and picoplankton) was measured using ¹⁵N isotope techniques. …
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Bacterioplankton dynamics in the Southern Benguela upwelling region
… role of heterotrophic bacteria in the carbon and nitrogen flux of the pelagic food web was investigated during laboratory and field-based studies of the temporal development of the planktonic community after upwelling. Bacterial community structure, activity and production were closely coupled to …
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Nitrate and Ammonium Transformation and Fate in Groundwater of an Agricultural Watershed: An Isotope and Geochemistry Approach
… transformation and attenuation processes in the nitrogen cycle. Groundwater delta18O and delta2H results indicate that recharge occurs predominantly in late fall as photosynthetic transpiration declines and in late spring following spring thaw, when vegetation is inactive. The abundance of …
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Primary production of particulate protein amino acids : algal protein metabolism and its relationship to the composition of particulate organic matter
… with conversion of inorganic carbon and nitrogen into protein, the effects of NH+4 limitation on free amino acid and protein composition and incorporation of inorganic 14C were studied in the marine chlorophyte, Nannochloris sp. (clone GSB Nanna). Free amino acid metabolism was sensitive …
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Interactive effects of hemlock mortality and nitrogen availability on nutrient pools and fluxes in the southern Appalachian Mountains
… (Tsuga canadensis) exerts strong control on nitrogen (N) dynamics, and its loss due to infestation by the hemlock woolly adelgid (Adelges tsugae) is expected to affect nutrient dynamics in impacted stands. I evaluated the potential for variation in N availability to influence the magnitude of …