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Analysis Of Miocene Stratigraphy And Sedimentology In The Ross Sea, Antarctica: A First Order Test Of Proxy Based Climate Interpretations, Samuel Gray Jan 2007

Analysis Of Miocene Stratigraphy And Sedimentology In The Ross Sea, Antarctica: A First Order Test Of Proxy Based Climate Interpretations, Samuel Gray

LSU Master's Theses

During the Cenozoic, the climate progressed from global warmth into an icehouse world. This study investigates the links between the development of the climate and cryosphere using sediment flux and stratal geometries. The current polar conditions are characterized by dry basal conditions, which due to minimal melt water produce significantly less sediment than their temperate counterparts. Therefore, the transition from temperate to polar conditions should have resulted in marked decrease in sediment flux and change in stratal geometries in adjacent marine margins. Regional seismic stratigraphic evidence clearly suggests that ice has been intermittently grounded on the Ross Sea outer continental …


Fluid Flow In The Central North Slope Foreland Basin, Alaska, Anna Marie Bélanger Jan 2007

Fluid Flow In The Central North Slope Foreland Basin, Alaska, Anna Marie Bélanger

LSU Master's Theses

Previous studies of the areal variations in heat flow and spatial variations in formation water salinity and hydraulic head are consistent with the existence of a currently active, topographically-driven regional fluid flow regime in the National Petroleum Reserve Alaska (NPRA) portion of the western North Slope foreland basin. This conclusion is also supported by the results of numerical modeling of fluid flow and heat transport in the area. This work has now been extended to the east. The results of this study demonstrate that the Permian though Cenozoic age sediments of the central North Slope foreland basin have been significantly …


Empirical Modeling Of Late Quaternary Sediment Supply To The Gulf Of Mexico Shelf Margin In A Cool Lowstand World, Jill Hattier Womack Jan 2007

Empirical Modeling Of Late Quaternary Sediment Supply To The Gulf Of Mexico Shelf Margin In A Cool Lowstand World, Jill Hattier Womack

LSU Master's Theses

During the last glacial period, river systems responded to the lowering of sea level by incising valleys, extending across the continental shelf, and depositing deltas on the shelf margin and upper slope of surrounding basins. These deltas represent important repositories for sediment delivered to the coastal ocean and provide partial records of sediment discharged from continental landmasses. Over relatively short time scales, like that of the last glacial-interglacial cycle, hinterland drainage areas, relief and lithology can be considered constants while the primary variable of significance is climate change (Syvitski and Milliman, 2007). It is reasonable to assume, therefore, that supply …


Carbonated Sections From Komatiite Flow- Top Alteration Zones In The Barberton Greenstone Belt: Implications For Near-Surface Archean Environments, Judith E. F. Stoute Jan 2007

Carbonated Sections From Komatiite Flow- Top Alteration Zones In The Barberton Greenstone Belt: Implications For Near-Surface Archean Environments, Judith E. F. Stoute

LSU Master's Theses

Over a dozen komatiitic flows in the 3.2-3.5 Ga Barberton Greenstone Belt are topped with unique green silica- and carbonate-rich rocks, which likely formed from interaction of the cooling lava flow with seawater shortly after deposition. This study focuses on an alteration zone in the Mendon Formation. Two styles of alteration are observed in this alteration zone: silicification and carbonation. The goal of this study is to characterize the carbonates in the alteration zone, constrain the timing of alteration, test whether the alteration zones are due to interaction with seawater after deposition, and estimate the elemental fluxes between the rock …


Developing A Rapid Method For Assessing The Physical Stability Of Streams In Minnesota's Agassiz Beach Ridges, Abigail V. Franklund Jan 2007

Developing A Rapid Method For Assessing The Physical Stability Of Streams In Minnesota's Agassiz Beach Ridges, Abigail V. Franklund

Theses and Dissertations

This thesis assessed the physical characteristics and stability of selected western Minnesota streams that cross the eastern beach ridges of glacial Lake Agassiz. Stream and river channels in this area host unusually diverse aquatic habitat and biodiversity, but incompatible land use along channels and in watersheds impair their quality and function. Previous rapid assessment protocols have been developed for stream attributes and stability, but these methods have been developed elsewhere in the United States and are not necessarily appropriate for western Minnesota’s unique geology and landscape.

A rapid reconnaissance method was developed to assess stream conditions using an integrated numerical …


The Environmental Implications Of Aggradation In Major Braided Rivers At Mount Rainier National Park, Washington, Scott Robert Beason Jan 2007

The Environmental Implications Of Aggradation In Major Braided Rivers At Mount Rainier National Park, Washington, Scott Robert Beason

Dissertations and Theses @ UNI

The purpose of this study is to quantify the historic rate of river bed filling, and to the extent possible, evaluate the factors that control sedimentation in river channels at Mount Rainier National Park. Mount Rainier is the tallest and the most glaciated of the Cascade volcanoes, located in southwestern Washington State. Steep, glacially-fed braided rivers radiate outward from the volcano in all directions and transport materials varying from fine sediment to cobbles and large boulders. As the gradient in the channels decreases downstream, sediment is no longer entrained and accumulates in the river bed. Over time, the river bed …


Paleoceanography Of The Gulf Of Papua Using Multiple Geophysical And Micropaleontological Proxies, Lawrence A. Febo Jan 2007

Paleoceanography Of The Gulf Of Papua Using Multiple Geophysical And Micropaleontological Proxies, Lawrence A. Febo

LSU Doctoral Dissertations

Recent marine and late Pleistocene sediments examined from the Gulf of Papua (GoP), Papua New Guinea investigate the flux and fate of detrital sediments and organic carbon over the last glacial-interglacial cycle. Based on surface sediment magnetic susceptibility (MS) and calcium carbonate concentrations, recent marine sediment is exported off the narrow shelf and into deeper regions via the Kerema Canyon of the northern Pandora Trough. Detrital clastic sediment is then dispersed deeper into the central and southern Pandora Trough. Except for pelagic deposition, very little detrital material reaches the Ashmore Trough and Eastern Plateau adjacent to the Great Barrier Reef. …


Observation Of Microslip Dynamics At High-Speed Microcontacts, Brian Borovsky, Adam M. Booth, Erin Manlove Jan 2007

Observation Of Microslip Dynamics At High-Speed Microcontacts, Brian Borovsky, Adam M. Booth, Erin Manlove

Geology Faculty Publications and Presentations

The high-speed tribological properties of microscale contacts are studied using an indenter probe and quartz crystal microbalance. Elastic and dissipative shear forces are monitored as a function of contact radius for sapphire/gold interfaces with an adsorbed octadecanethiol monolayer. We observe shear force transitions understood as taking the interface from slipping to stuck conditions. We relate this behavior to the presence of interfacial microslip. Dynamic modeling shows that our observations are consistent with an interface that, when sliding, experiences full slip during half of each cycle. We discuss the implications for this technique as a sensitive probe of sliding friction.


Oliver Ranch Science School Complex & Wild Horse And Burro Facility: Final Close-Out Report, Margaret N. Rees Dec 2006

Oliver Ranch Science School Complex & Wild Horse And Burro Facility: Final Close-Out Report, Margaret N. Rees

Oliver Ranch Project

“The mission of the Red Rock Desert Learning Center is to instill stewardship and respect by increasing knowledge and understanding of the Mojave Desert ecosystems and cultures through a unique experiential discovery program.”


Varietal Role In The Management Of The Larger Grain Borer, Prostephanus Truncatus (Horn) In Stored Maize, C. P. Rugumamu Dec 2006

Varietal Role In The Management Of The Larger Grain Borer, Prostephanus Truncatus (Horn) In Stored Maize, C. P. Rugumamu

Tanzania Journal of Science

The study determined the amount of haemolymph vitellogenin (Vg) of the Larger Grain Borer (LGB), Prostephanus truncatus (Horn) vitellogenic females reared on different maize varieties. The varieties were ZM 521, ZM 421, ECAVL1-DLN, WEEVIL A, LOCAL 1 and LOCAL 2. Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis (SDS - PAGE) was conducted on the insect haemolymph. F1 LGB adults from each variety were used to determine Indices of Susceptibility (IS) of the varieties to the insect pest attack. Percentages of Vg from female insects and IS were in the order ZM 521>ZM 421> ECAVL1-DLN>WEEVIL A >LOCAL 1>LOCAL 2. Weight …


Evaluating The Performance Of Leucaena Accessions For Agroforestry In Sub-Humid Environment, Southern Tanzania, A. E. Majule Dec 2006

Evaluating The Performance Of Leucaena Accessions For Agroforestry In Sub-Humid Environment, Southern Tanzania, A. E. Majule

Tanzania Journal of Science

The performance of Leucaena accessions on acid soils in eastern coast Tanzania for agroforestry was evaluated for three years. Plant tree parameters assessed were fodder yield and plant stem height, stem girth, the number of total branches and poles production. Also, Leucaena psyllid, a common pest threatening the plants was also counted. Soil parameters assessed were pH organic carbon, total nitrogen, exchangeable calcium and magnesium. Result showed significant difference in growth between Leucaena accessions. Leucaena leucocephal cv K8 and Leucaena diversifolia were able to grow fast reaching 4.7 and 3.3 m respectively within a period of three years. Leucaena diversifolia …


Properties Of Fired Bodies Made From Tanzanian Talc-Clay Mixes For Ceramic Applications., E. H. J. Lugwisha Dec 2006

Properties Of Fired Bodies Made From Tanzanian Talc-Clay Mixes For Ceramic Applications., E. H. J. Lugwisha

Tanzania Journal of Science

Fired properties of talc-clay mixed bodies of different compositions were investigated for ceramic applications. Clays from Pugu and Malangali and talcs from two different sites in Kikombo deposits in Dodoma Region were used. Chemical analyses, X-ray analysis and Differential Thermal analysis for clays and talcs were used for the characterisation. Moulded mixed samples of clay and talc dried at room temperature at 1100C for 24 hours were fired at 1200, 1250, 1300 and 13500C for 6 hours. Both clay deposits consist mainly of kaolin. Talc1 - T1 is of higher purity than Talc - T2. Furthermore, the percentage shrinkage of …


Thermal And X-Ray Investigations Of Kowak Clay In Northwestern Tanzania And Its Possible Industrial Use, E. H. J. Lugwisha Dec 2006

Thermal And X-Ray Investigations Of Kowak Clay In Northwestern Tanzania And Its Possible Industrial Use, E. H. J. Lugwisha

Tanzania Journal of Science

A study of some properties of clays collected from selected sites in Kowak deposit in Tarime District was carried out in order to assess their suitability as raw materials in ceramic and its related industries. The silica (SiO2) content in the clays is predominant, and is about 66.89% followed by alumina (Al2O3) that is 20.2%. Haematite (Fe2O3) was found to be the third in abundance with an average of 3.58%. Other constituents are present in small proportions. Water loss at 105 oC lies between 2.70% and 2.76%. DTG, TG, XRD techniques and chemical analyses studied by AAS method were used …


Limnological Studies Of The Pelagic Zone Of Lake Tanganyika At Kigoma, Tanzania., F. M. M. Chale Dec 2006

Limnological Studies Of The Pelagic Zone Of Lake Tanganyika At Kigoma, Tanzania., F. M. M. Chale

Tanzania Journal of Science

Some limnological parameters and chlorophyll a were determined for twelve months at a pelagic station near Kigoma. Temperatures ranged between 25.7 ºC and 27.3 ºC at the surface, and 24.1 oC and 24.7 oC at100 m. Thermal stratification persisted throughout the year with the thermocline oscillating between 15 m in October and 60 m in May. Dissolved oxygen concentrations were high at the surface, ranging between 6.59 mg l-1 and 8.15 mg l-1, while at 100 m the concentrations ranged from less than 0.20 mg l-1 to 1.94 mg l-1. Nitrate-nitrogen concentrations in surface water ranged between 26 µg N …


Assessment Of The Status Of Lates Stappersii (Centropomidae) Stock In Lift-Net Fishery In Lake Tanganyika, Kigoma, Tanzania, I. A. Kimirei, Y. D. Mgaya Dec 2006

Assessment Of The Status Of Lates Stappersii (Centropomidae) Stock In Lift-Net Fishery In Lake Tanganyika, Kigoma, Tanzania, I. A. Kimirei, Y. D. Mgaya

Tanzania Journal of Science

An assessment of the status of Lates stappersii (Boulenger, 1914) stock in the lift-net fishery in Lake Tanganyika, Kigoma area, was carried out from January to December 2003. Results indicated that breeding is seasonal with peaks in February, July-August and December, and so was catch composition, with peaks in March, May and July–August that followed the abundance of its prey, Stolothrissa tanganicae. Catch per unit effort was similar between wet and dry seasons and peaked synchronously at all study sites probably as an indication of its abundance during those months; but also it could mean that the fishes were caught …


A New View Of Ridge Segmentation And Near-Axis Volcanism At The East Pacific Rise, 8˚–12˚N, From Em300 Multibeam Bathymetry, Scott M. White, Rachel M. Haymon, S M. Carbotte Dec 2006

A New View Of Ridge Segmentation And Near-Axis Volcanism At The East Pacific Rise, 8˚–12˚N, From Em300 Multibeam Bathymetry, Scott M. White, Rachel M. Haymon, S M. Carbotte

Faculty Publications

New, high-resolution bathymetry for the East Pacific Rise between 8˚N and 12˚N was collected over a6 km wide swath centered on the ridge axis using the 30 kHz Simrad EM300 multibeam system. Thecoverage area corresponds latitudinally to the designated Ridge2000 Integrated Studies Site (ISS) for fastspreading ridges. The EM300 data, gridded at 30 m latitude by 50 m longitude, represent a greater than 4Ximprovement in horizontal resolution over previously available multibeam data and a 2X improvement indepth resolution. The new bathymetry was used to update the locations and hierarchy of ridge offsets forthis area. Among the many applications for this …


Responses Of Pond-Breeding Amphibians To Wildfire: Short-Term Patterns In Occupancy And Colonization, Blake R. Hossack, Paul Stephen Corn Dec 2006

Responses Of Pond-Breeding Amphibians To Wildfire: Short-Term Patterns In Occupancy And Colonization, Blake R. Hossack, Paul Stephen Corn

United States Geological Survey: Staff Publications

Wildland fires are expected to become more frequent and severe in many ecosystems, potentially posing a threat to many sensitive species. We evaluated the effects of a large, stand-replacement wildfire on three species of pond-breeding amphibians by estimating changes in occupancy of breeding sites during the three years before and after the fire burned 42 of 83 previously surveyed wetlands. Annual occupancy and colonization for each species was estimated using recently developed models that incorporate detection probabilities to provide unbiased parameter estimates. We did not find negative effects of the fire on the occupancy or colonization rates of the long-toed …


Fate Of Fish Production In A Seasonally Flooded Saltmarsh, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak Dec 2006

Fate Of Fish Production In A Seasonally Flooded Saltmarsh, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak

United States Geological Survey: Staff Publications

Although saltmarshes are thought to enhance the productivity of open estuarine water, the mechanism by which energy transfer occurs has been debated for decades. One possible mechanism is the transfer of saltmarsh production to estuarine waters by vagile fishes and invertebrates. Monthly estimates of fish standing stock, net fish ingress, and predation were used to develop a bio-mass budget to estimates annual production of fishes and the relative yield to predatory fish, birds, and direct migration to the estuary. Annual production of saltmarsh fishes was estimated to 31.0 gm-2 saltmarsh, which falls within the range of previously reported values …


Assessment Of Atrazine In A Rural Water Source: Rough River Lake, Kentucky, Scotty Sharp Dec 2006

Assessment Of Atrazine In A Rural Water Source: Rough River Lake, Kentucky, Scotty Sharp

Masters Theses & Specialist Projects

Atrazine [2-chloro- 4-(ethylamino)-6-(isopropylamino)-l,3,5-triazine], a widely used herbicide in US corn production, impacts quality of drinking water for many rural water supply systems. Four systems at Rough River Lake, Kentucky, have had high levels of atrazine in raw water and in some cases finished water that have exceeded the legal limit of 3 parts per billion (ppb). The Rough River Lake watershed is 1,700-km2, much of which is located in limestone karst. A hypothesis was developed stating that there would be higher concentrations of atrazine in the northeast section of the Rough River Watershed, located in Hardin County, due to the …


Modeling Soil Erosion In The Upper Green River, Ky, Narcisa Pricope Dec 2006

Modeling Soil Erosion In The Upper Green River, Ky, Narcisa Pricope

Masters Theses & Specialist Projects

Off-site soil erosion has tremendous impacts on the present state of most river systems throughout the United States, contributing sediments to channels mainly as nonpoint pollution resulting from land-use and agricultural practices and leading to sedimentation downstream and downwind, a decrease in the transport capacity of streams, increase in the risk of flooding, filling reservoirs, and eutrophication. A primary focus in examining the problems associated with soil erosion arid ultimately in proposing control measures should be on identifying the sources of the sediment. Therefore, a model that would be able to assess soil erosion needs to start by identifying the …


Flash Flooding In Eastern Kentucky: An Analysis Of The 3-4 August 2001 Event, Christina Henry Dec 2006

Flash Flooding In Eastern Kentucky: An Analysis Of The 3-4 August 2001 Event, Christina Henry

Masters Theses & Specialist Projects

Limited research exists concerning flash flooding in the United States. However, flash floods can occur anywhere and cause more fatalities than any other weather related natural disaster. Eastern Kentucky experienced an average of 41 flash floods per year (1993-2002), yet little research exists for this region. Therefore, this paper presents an analysis of the particularly devastating flash flood event of 3-4 August 2001, which resulted in $15 million worth of property damage and two deaths. Previous studies indicate that flash floods typically occur under relatively 'benign' conditions, the most common characteristics being a quasi-stationary system and high atmospheric moisture. The …


Identification, Characterization And Analysis Of Wrench Related Faulting In Southwestern Warren County, Kentucky, Joseph Islas Dec 2006

Identification, Characterization And Analysis Of Wrench Related Faulting In Southwestern Warren County, Kentucky, Joseph Islas

Masters Theses & Specialist Projects

Warren County, Kentucky is located south of the southern boundary of the Rough Creek Graben marked by the Pennyrile fault system. The Pennyrile fault system is a regional southwest-northeast trending fault system that extends into Kentucky from the Reelfoot rift zone. The Rough Creek fault system bounds the northern arm of the Rough Creek Graben and trends northwest-southeast also extending from the Reelfoot rift zone. The Rough Creek fault system is related to the Shawneetown fault system in southeastern Illinois and occupies the southern end of the Illinois Basin. The East Continent Rift Basin intersects the Rough Creek Graben near …


Geosciences Newsletter - 2006, Department Of Geosciences Dec 2006

Geosciences Newsletter - 2006, Department Of Geosciences

Geological and Environmental Sciences News

Vol. 2, No. 2

  • Mohamed Sultan, Chairperson
  • Faculty News
  • Department News
  • Michigan Geological Repository for Research and Education (MGRRE)
  • Department Updates
  • Graduate Student News
  • Awards & Graduations
  • Alumni News
  • Outstanding Alumni Academy
  • Dedication Ceremony Michigan Geological Repository for Research and Education (MGRRE) New Faces in the Geosciences


Biomass Estimation And Classification Of Secondary Succession Using Radar And Optical Remote Sensing Data Based On Textural And Spectral Analysis In Amazonia, Ping Jiang Dec 2006

Biomass Estimation And Classification Of Secondary Succession Using Radar And Optical Remote Sensing Data Based On Textural And Spectral Analysis In Amazonia, Ping Jiang

All-Inclusive List of Electronic Theses and Dissertations

Deforestation that happened during past decades in the Amazon Basin has been potentially affecting the global climate and carbon-cycle by contributing a vast amount of carbon into the atmosphere. Above-ground biomass (AGB) estimation of secondary successional and mature forests using remote sensing technology has been attracting scientists' attention. Optical sensor data are sensitive to forest canopies only, and therefore have limitations in AGB estimation, especially for tropical forests with complex structures and abundant species. Radar signals have the ability to penetrate canopies to detect the sub-layers of forests, and therefore potentially have a better performance in AGB estimation. Based on …


Investigation Of Oxy-Anion Legand Adsorption Onto Surfaces Of Iron Oxide And Bacteria In Groundwater Aquifers, Haile Mengistu Dec 2006

Investigation Of Oxy-Anion Legand Adsorption Onto Surfaces Of Iron Oxide And Bacteria In Groundwater Aquifers, Haile Mengistu

Dissertations

We have measured adsorption of dissolved phosphate onto synthetic hydrous ferric oxide (HFO), dissolved arsenate and chromate onto the cell membrane of a bacterium species, S. putrefaciens as a function of pH, ionic strength, and relative concentrations of the respective oxy-ligands. Our experimental data were used to constrain optimal values for surface complexation reactions involving dissolved oxi-ligands (phosphate, and chromate) and the HFO surface and the cell membrane of S. putrefaciens respectively according to the diffuse layer model.

Our results provide a more accurate fit to experimental measurements over a broader range of pH (3 - 12), ionic strength and …


Marine Sediment Record From The East Antarctic Margin Reveals Dynamics Of Ice Sheet Recession, Amy Leventer, Eugene Domack, Jennifer Pike, Catherine Stickley, Eleanor Maddison, Stefanie A. Brachfeld, Patricia Manley, Charlie Mcclennen Dec 2006

Marine Sediment Record From The East Antarctic Margin Reveals Dynamics Of Ice Sheet Recession, Amy Leventer, Eugene Domack, Jennifer Pike, Catherine Stickley, Eleanor Maddison, Stefanie A. Brachfeld, Patricia Manley, Charlie Mcclennen

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Antarctic shelf is traversed by large-scale troughs developed by glacial erosion. Swath bathymetric, lithologic, and chronologic data from jumbo piston cores from four sites along the East Antarctic margin (Iceberg Alley, the Nielsen Basin, the Svenner Channel, and the Mertz-Ninnis Trough) are used to demonstrate that these cross-shelf features controlled development of calving bay reentrants in the Antarctic ice sheet during deglaciation. At all sites except the Mertz-Ninnis Trough, the transition between the Last Glacial Maximum and the Holocene is characterized by varved couplets deposited during a short interval of extremely high primary productivity in a fjordlike setting. Nearly …


The Formation And Obduction Of Ophiolites Since The Late Precambrian, Stacey Metzler Dec 2006

The Formation And Obduction Of Ophiolites Since The Late Precambrian, Stacey Metzler

Earth & Environmental Sciences Theses - Archive

Ophiolite formation and emplacement has been episodic since the Late Precambrian. This research study examines ophiolites that formed during the Cenozoic, Mesozoic, Paleozoic and Late Precambrian. The ophiolites were plotted on paleogeographic reconstructions using PALEOMAP Project maps, and the ophiolite localities were analyzed by their temporal distribution in relation to the tectonic framework in which they were emplaced. The ophiolites appear to show episodic events linked to global plate reorganization. These episodes coincide with collisional events from the supercontinents of Gondwana and Pangea. The primary mechanisms of formation and emplacement proved to be mid-ocean ridge systems and back arc basins …


Issues During The Inversion Of Crosshole Radar Data: Can We Have Confidence In The Outcome?, William P. Clement Dec 2006

Issues During The Inversion Of Crosshole Radar Data: Can We Have Confidence In The Outcome?, William P. Clement

Geosciences Faculty Publications and Presentations

One method of assessing the confidence in modeled features is to compare the results from different inversion schemes. I use synthetic traveltimes calculated from a model of an unconfined aquifer to determine the reliability of crosshole tomography. I compare the inverted models from straight and curved ray approximations to wave propagation. I investigate the effects of added random noise, regularization, the starting model, and the reference model on the curved ray inversion method. I also investigate the effects of different grid sizes for the forward model and of limited ray coverage through the earth model. Understanding the effects of these …


A Linear Modulation Osl Study Of The Unstable Ultrafast Component In Samples From Glacial Lake Hitchcock, Massachusetts, Usa, R. J. Goble, Tammy M. Rittenour Dec 2006

A Linear Modulation Osl Study Of The Unstable Ultrafast Component In Samples From Glacial Lake Hitchcock, Massachusetts, Usa, R. J. Goble, Tammy M. Rittenour

Geosciences Faculty Publications

Optical ages were determined for samples from delta and sand dune deposits associated with Glacial Lake Hitchcock near Amherst, Massachusetts using the single aliquot regenerative-dose (SAR) optically stimulated luminescence (OSL) technique. However, a strong unstable ultrafast component caused initial rejection of data from a large proportion of aliquots. A linearly modulated blue OSL (LM-OSL) study was undertaken on the sample with the strongest ultrafast component, with the data modelled using the equation of Bulur et al. (2000) as 5 fast, medium and slow components, and 1 ultrafast component.

The ultrafast component dominates the LM–OSL, almost completely obscuring the fast component. …


Thermodynamics Of Metals Adsorption Onto Uranium Dioxide, Koi Ling Lim Dec 2006

Thermodynamics Of Metals Adsorption Onto Uranium Dioxide, Koi Ling Lim

Masters Theses

Wastes and pollution containing uranium are released to the environment through mining, ore processing, industrial manufacture of nuclear fuel and weapons materials, and the disposal of spent nuclear fuel. There are a wide variety of processes that can affect UO2 stability. This research focuses on the surface reactivity of UO2 in reducing aqueous solutions, with an emphasis on assessment of the pH-dependent surface charge, reactive surface area, and the adsorption of dissolved lead (Pb), cadmium (Cd), lanthanum (La) onto UO2 particles. A surface complexation model was used to explain the adsorption and titration phenomena of UO2 …