The quantification of plutonium (Pu) in spent nuclear fuel is an increasingly important safeguards issue. There exists an estimated worldwide 980 metric tons of Pu in the nuclear fuel cycle and the majority is in spent nuclear fuel waiting for long term storage or fuel reprocessing. This study investigates utilizing the measurement of x-ray fluorescence (XRF) from the spent fuel for the quantification of its uranium (U) to Pu ratio. Pu quantification measurements at the front end of the reprocessing plant, the fuel cycle area of interest, would improve input accountability and shipper/receiver differences. XRF measurements were made on individual PWR fuel rods with varying fuel ages and final burn-ups at Oak Ridge National Laboratory (ORNL) in July 2008 and January 2009. These measurements successfully showed that it is possible to measure the Pu x-ray peak at 103.7 keV in PWR spent fuel (~1 percent Pu) using a planar HPGe detector. Prior to these measurement campaigns, the Pu peak has only been measured for fast breeder reactor fuel (~40 percent Pu). To understand the physics of the measurements, several modern physics simulations were conducted to determine the fuel isotopics, the sources of XRF in the spent fuel, and the sources of Compton continuum. Fuel transformation and decay simulations demonstrated the Pu/U measured peak ratio is directly proportional to the Pu/U content and increases linearly as burn-up increases. Spent fuel source simulations showed for 4 to 13 year old PWR fuel with burn-up ranges from 50 to 67 GWd/MTU, initial photon sources and resulting Compton and XRF interactions adequately model the spent fuel measured spectrum and background. The detector simulations also showed the contributions to the Compton continuum from strongest to weakest are as follows: the fuel, the shipping tube, the cladding, the detector can, the detector crystal and the collimator end. The detector simulations showed the relationship between the Pu/U peak ratio and fuel burn-up over predict the measured Pu/U peak but the trend is the same. In conclusion, the spent fuel simulations using modern radiation transport physics codes can model the actual spent fuel measurements but need to be benchmarked.

A process for recycling spent nuclear fuel cladding, a zirconium alloy (Zircaloy), into a metal powder that may be used for advanced nuclear fuel applications, was investigated to determine if it is a viable strategy. The process begins with hydriding the Zircaloy cladding hulls after the spent nuclear fuel has been dissolved from the cladding. The addition of hydrogen atoms to the zirconium matrix stresses the lattice and forms brittle zirconium hydride, which is easily pulverized into a powder. The dehydriding process removes hydrogen by heating the powder in a vacuum, resulting in a zirconium metal powder. The two main objectives of this research are to investigate the dehydriding process and to design, build and demonstrate a specialized piece of equipment to process the zirconium from cladding hulls to metal powder without intermediate handling. The hydriding process (known from literature) took place in a 95 percent argon - 5 percent hydrogen atmosphere at 500 degrees C while the dehydriding process conditions were researched with a Thermogavimetric Analyzer (TGA). Data from the TGA showed the dehydriding process requires vacuum conditions (~0.001 bar) and 800 degrees C environment to decompose the zirconium hydride. Zirconium metal powder was created in two separate experiments with different milling times, 45 minutes (coarse powder) and 12 hours (fine powder). Both powders were analyzed by three separate analytical methods, X-Ray Diffraction (XRD), size characterization and digital micrographs. XRD analysis proved that the process produced a zirconium metal. Additionally, visual observations of the samples silvery color confirmed the presence of zirconium metal. The presence on zirconium metal in the two samples confirmed the operation of the hydriding / milling / hydriding machine. Further refining of the hydride / milling / dehydride machine could make this process commercially favorable when compared to the high cost of storing nuclear waste and its components. An additional important point is that this process can easily be used on other metals that are subject to hydrogen embrittlement, knowing the relevant temperatures and pressures associated with the hydriding / dehydriding of that particular metal.

An RDD attack against the U.S. is something America needs to prepare against. If such an event occurs the ability to quickly identify the source of the radiological material used in an RDD would aid investigators in identifying the perpetrators. Spent fuel is one of the most dangerous possible radiological sources for an RDD. In this work, a forensics methodology was developed and implemented to attribute spent fuel to a source reactor. The specific attributes determined are the spent fuel burnup, age from discharge, reactor type, and initial fuel enrichment. It is shown that by analyzing the post-event material, these attributes can be determined with enough accuracy to be useful for investigators. The burnup can be found within a 5% accuracy, enrichment with a 2% accuracy, and age with a 10% accuracy. Reactor type can be determined if specific nuclides are measured. The methodology developed was implemented into a code call NEMASYS. NEMASYS is easy to use and it takes a minimum amount of time to learn its basic functions. It will process data within a few minutes and provide detailed information about the results and conclusions.

Distillers’ spent grain (DSG) is a by-product of ethanol production and used for swine feed supplement due to its nutrient composition. Lowering the moisture content of DSG using superheated steam (SS) drying can be more energy efficient compared to hot air drying. One objective was to investigate parameters associated with SS drying on DSG including maximum condensation, condensation time, and restoration time. Increasing SS temperature from 120 to 180 °C and SS velocity from 1.0 to 1.4 m/s resulted in a 97% and 67% decrease in maximum condensation, respectively. Another objective was to determine the effect of SS temperature, velocity, and pellet orientation on effective moisture diffusivity of DSG pellets. The diffusion model was based on finite cylinder geometry accounting for volumetric shrinkage. The diffusivity coefficient was determined to be 1.56 × 10-8 m2/s. A significant effect of pellet orientation on moisture diffusivity was found during the constant drying-rate period. / October 2015

No description available.

Thesis (M.S.)--University of Nevada, Reno, 2007. / "December, 2007." Includes bibliographical references (leaves 25-28). Online version available on the World Wide Web.

Overuse of the chemical compounds and toxic elements leads to problems and transmission of contaminants and pollutants to humans and other living organisms. One of the industries’ byproducts of the agriculture sector is production of various composts from the organic raw materials that the best type of which is so – called Vermicompost. In this study, effects of raw materials on qualitative and quantitative characteristics of Vermicompost are discussed. To do so, sheep manure, pomegranate peels, spent mushroom compost either singly or double, triple or fourfold chopped corn, sugar beet pulp and sawdust were used. This research project was conducted in a completely randomized design experiment with 23 treatments with 3 replications. Results revealed that various bed combinations exert different effects on Vermicompost quality such that, the Vermicomposting process led to a significant decrease in electrical conductivity (EC) and a significant increase in pH in most of the culture (seed) beds. Also, the levels of Nitrogen, Phosphorous and Potassium in most treatments increased following completion of the vermicomposting process. As a result, this process can be introduced as an organic fertilizer with complete nutrients for improving chemical characteristics of agricultural wastes to usable fertilizers.

The purpose of this study was to analyze the relationship between attitudes toward the division of household tasks and the amount of time spent accomplishing them by Utah husbands and wives. The sample was 200 husbands and 203 wives residing in Iron, Washington, and Salt Lake Counties . A questionnaire was used to measure the respondents' attitudes toward the division of household labor and two, 24-hour time diaries were used to record time expenditures. Hypotheses regarding traditional and non-traditional attitudes related to the amount of time spent in traditional female t asks, traditional male tasks and time spent in all household tasks were tested. Analysis of variance and Pearson's Product Moment Correlation were used to analyze the data. No statistically significant results were found when husbands' and wives' attitudes toward the allocation of household tasks were related to the amount of time spent in traditional female tasks, traditional male tasks, and total housework It was concluded that attitudes towards the division of household tasks as measured in this research did not predict or influence the amount of time spent accomplishing household tasks.

Brewer's spent grain (BSG) is a main by-product of beer manufacturing and is rich in nutrients including 15-30% protein, making it a potentially valuable protein source for human food. Current challenges of extracting protein from BSG include low yields and high manufacturing costs, but the rising trend of plant-based diets for environmental and health reasons increases BSG's appeal. This research proposes an innovative extraction process utilizing wet fractionation and enzymatic purification that targets fiber to effectively separate proteins form BSG. Additionally, the feasibility of BSG protein as a food ingredient is explored, offering a unique approach that limits harsh processing commonly used for protein extraction. The choice of the enzyme (CTec 2 and Viscozyme L), enzyme dose, and incubation time (1, 3, 6, 9, and 24 hrs) were investigated to maximize protein content and recovery and further evaluate processing effects on protein functionality. Following wet fractionation, there was a notable reduction in fiber from 48.6% in the BSG to 22.5% in the filtrate (PRF) on a dry basis. Additionally, the protein content increased from 22.8 to 40.0% from the BSG to the PRF, respectively. The coarse fiber (CF) had an average protein content of 6.30%, highlighting the effectiveness of wet fractionation in enhancing protein recovery from BSG. The optimal enzymatic treatments condition identified was using CTec 2 to degrade fiber at a dose of 6.00% (g enzyme/g solid) for 24 hours. The enzymatic fiber hydrolysis proved to be able to remove lignocellulosic biomass from BSG resulting in a defatted protein concentrate (DPC) with a high protein content (52.8%) along with a high recovery rate (63%). All treatments resulted in protein functionality similar to the two control treatments. Varying fiber hydrolysis conditions did not have a significant effect on the functional properties. Several functional properties were improved using limited hydrolysis (LH) using proteases. LH had negative impacts on foaming stability and emulsifying properties; however, it improved the solubility, foaming capacity, WHC, and OHC of the BSG protein. Potential applications for the DPC include low moisture applications such as protein bars or granola. The DPCs could also have potential use in meat alternatives due to the high WHC and OHC and the need for varying protein solubility in meat alternatives. The LH protein has greater potential in applications such as protein beverages due to the high solubility. This process presents a promising protein extraction approach from BSG, offering producers the flexibility to tailor it to their specific application needs. After obtaining the protein concentrate, additional steps like defatting or limited hydrolysis can be applied to improve the purity and functionality of the result protein. Notably, this approach contributes to sustainable food production by addressing food waste and meeting the rising demand for sustainable protein sources to support the nutritional needs of a growing global population. / Master of Science in Life Sciences / Brewer's spent grain (BSG) is a by-product of beer manufacturing with rich nutrients, including 15-30% protein. It holds potential as a valuable protein source for human food. Current challenges of extracting protein from BSG include low yields and high costs, but the rising trend of plant-based diets for environmental and health reasons increases BSG's appeal. Its abundant availability year-round makes it an attractive option for human food. In this study, an innovative process to extract protein from BSG was explored using wet fractionation to separate the BSG by size. Enzymes were then used to remove remaining fiber. Various enzymes and times were tested to optimize extraction and achieve a high protein content and recovery rate. The protein's physicochemical and functional properties were then evaluated for potential uses in human food. After wet fractionation, nearly half the fiber was removed, and the protein content increased by 17.2%. Using an enzyme called CTec 2 for 24 hours worked best, resulting in a protein concentrate with a high protein content (52.8%) and good recovery (63.0%). Changes in enzyme treatments did not have a significant effect on the protein functional properties. Potential applications for the protein concentrates include low moisture applications such as protein bars or granola due to the poor solubility. The protein concentrates could also have potential use in meat alternatives due to the water and oil holding properties. The low solubility of the protein concentrates was improved using a process called limited hydrolysis making it possible to apply to products like protein beverages. This research highlights BSG's potential as a valuable protein source for protein bars, meat alternatives, and protein beverages. These findings provide a promising approach to utilize BSG as a valuable plant protein source for a healthier and more environmentally friendly food production.

The traditional paradigm declares tetravalent uranium to be immobile under reducing conditions – an assumption widely employed for nuclear waste management strategies. In contrast, experiments presented here demonstrate this assumption, although valid for low temperatures, can be erroneous for high temperature natural systems. This project focuses on the ability of sulfate-bearing solutions to transport uranium at reduced conditions and elevated temperatures, identifies the new species U(OH)2SO4, derives thermodynamic constants necessary for modeling, and expands the quantifiable range of U4+ mobility to more neutral pH conditions. The data obtained enable more accurate assessment of uranium mobility by updating the existing uranium thermodynamic databases and is applicable to uranium fluid transport in oreorming systems and nuclear waste repositories.