Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Keyword
- Publication
Articles 1 - 5 of 5
Full-Text Articles in Physical Sciences and Mathematics
Toward Understanding The Thermodynamics And Mechanisms Of Actinide Sorption Reactions, Shanna Estes
Toward Understanding The Thermodynamics And Mechanisms Of Actinide Sorption Reactions, Shanna Estes
All Dissertations
The environmental fate of actinides is greatly influenced by interfacial reactions, including sorption onto solid surfaces. Because changes in the primary hydration sphere of the actinide are expected to greatly influence the thermodynamics (i.e., reaction enthalpy and entropy) of these reactions, examining actinide sorption thermodynamics may provide insight into actinide sorption mechanisms. Additionally, examining actinide sorption thermodynamics may enhance the ability to model or predict these reactions in environmental or engineered systems where variable or elevated temperatures are expected. However, few researchers have studied actinide sorption thermodynamics. Therefore, this research examined the thermodynamics of Eu(III) (a trivalent actinide analog), Th(IV), …
Transformation Of Uranium In A Geological Environment, Derrell Hood
Transformation Of Uranium In A Geological Environment, Derrell Hood
All Theses
Incorporation of uranium into iron oxide minerals is a promising mechanism for the environmental immobilization of U(VI). In this study, synthesized hematite was doped with uranium and analyzed with SEM-EDS, TEM, XRD, and ICP-MS. The results of this analysis strongly indicate uranium incorporation into the mineral, as well as the possible presence of a co-precipitated uranium mineral clarkeite. Preliminary results also shows an increase in the amount of uranium associated with the hematite particles as a function of mineral aging. Cyclic Voltammetry (CV) was used to induce and characterize electrochemical changes of uranium in the doped hematite system; these changes …
An Examination Of Radionuclide Transport In The Vadose Zone Using Field Lysimeters, Michael Witmer
An Examination Of Radionuclide Transport In The Vadose Zone Using Field Lysimeters, Michael Witmer
All Theses
Understanding how radionuclides interact in the subsurface is important for the remediation of contaminated sites, assessment of risk due to radioactive waste disposal, and designing new radioactive waste management strategies. The current understanding of the geochemical behavior of radionuclides in the subsurface and more specifically the vadose zone has been developed through reactive transport modeling supplemented by laboratory experiments. Interactions between radionuclides with the mineral particles and organic matter in the vadose zone can be very complex and while laboratory experiments produce valuable data, few controlled, intermediate scale transport studies have been performed. In order to accurately predict vadose zone …
Air-Regulated Siphon Spillways: Performance, Modeling, Design, And Construction, Joshua Boatwright
Air-Regulated Siphon Spillways: Performance, Modeling, Design, And Construction, Joshua Boatwright
All Theses
1:Little data exists in the literature for quantification of siphon spillway performance. Proper design of an air regulated siphon spillway requires knowledge of required flow rates and minimum vent size. A set of small siphon spillways were constructed to measure flow rate and required vent size relative to physical characteristics including pipe diameter, length of pipe, and elevation head. Vent sizing was shown to be logarithmically proportional to flow rate. Results were used to develop predictive models for flow rate and vent sizing. Models were validated and refined through testing on a siphon spillway installed on a pond at LaMaster …
Design Of A High Temperature Subsurface Thermal Energy Storage System, Qi Zheng
Design Of A High Temperature Subsurface Thermal Energy Storage System, Qi Zheng
All Theses
Solar thermal energy is taking up increasing proportions of future power generation worldwide. Thermal energy storage technology is a key method for compensating for the inherent intermittency of solar resources and solving the time mismatch between solar energy supply and electricity demand. However, there is currently no cost-effective high-capacity compact storage technology available (Bakker et al., 2008). The goal of this work is to propose a high temperature subsurface thermal energy storage (HSTES) technology and demonstrate its potential energy storage capability by developing a solar-HSTES-electricity generation system. In this work, main elements of the proposed system and their related state-of-art …