High temperature gas reactors (HTGR’s) have been researched and operated commercially since the inception of the nuclear industry. Newer designs, such as the General Atomics (GA) Modular HTGR, aim to lower capital costs by shifting towards smaller, more modular designs, although further cost reductions with respect to operations and maintenance...
Halogenated organic compounds have had widespread and massive applications in industry, agriculture, and private households, for example, as degreasing solvents, flame retardants and in polymer production. They are released to the environment through both anthropogenic and natural sources. The most common chlorinated solvents present as contaminants include tetrachloroethene (PCE, perchloroethene)...
An important improvement in the area of reactor core neutronic modeling is the development and use of the methods based on "quasi-diffusion" (QD) low-order equations. This family of methods takes into account the transport exactly using "functionals" computed by solving transport equations, and is amenable to solution with a variety...
In this work, metal-organic frameworks (MOFs) are computationally represented, generated, and evaluated. The organic linker molecules are represented as graphs and use graph grammars where the atoms are represented by nodes and the bonds are represented by arcs. The grammar rules that dictate the graph generation process work on the...
Arsenic in its inorganic form is naturally present in groundwater. Continued exposure to arsenic contaminated water can result in long lasting health complications, ranging from cognitive development issues to cancer. One method which may be convertible to a field test is the use of PEG functionalized gold nanoparticles which aggregate...
Freshwater systems are an important component of the global carbon cycle as they outgas disproportionately large quantities of carbon compared to the terrestrial landscape. Of particular importance are headwater streams, which represent roughly 90% of the channel network by length and have been conservatively estimated to outgas roughly 36% of...
Over the past decade the International Commission on Radiological Protection has developed a comprehensive approach to environmental protection that includes the use of Reference Animals and Plants (RAPs) to assess radiological impacts on the environment. For the purposes of calculating radiation dose, the RAPs are approximated as simple shapes that...
Using thermodynamic principles, the general relationship describing the equilibrium vapor content in the gas phase above a saline liquid and across a curved liquid-gas interface is developed. Since high salt concentration also affects the intensive and extensive liquid properties, it is also necessary to account for these effects in liquid...
Engineered capillary barriers typically consist of two layers of granular materials designed so that the contrast in sediment hydrologic properties and sloping interface retains infiltrating water in the upper layer. We report here on the results of two bench-top capillary barrier experiments, and associated modeling. These experiments were conducted to...
