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On Outflows Due To Radiation, Randall Cody Dannen
On Outflows Due To Radiation, Randall Cody Dannen
UNLV Theses, Dissertations, Professional Papers, and Capstones
Observations of ionized AGN outflows have provided compelling evidence that the radiation field transfers both momentum and energy to the plasma. At parsec scale distances in AGN, energy transfer can dominate, in which case the only force needed to launch an outflow is due to gas pressure. Much closer to the black hole, gravity dominates thermal energy due to insufficient heating by the radiation and the gas is in the so-called ’cold wind solution’ regime. Only magnetic or radiation forces can lead to outflow, but it is unclear how these forces depend on the spectral energy distribution (SED) and the …
Force Multiplier Calculations For X-Ray Binaries And Active Galactic Nuclei, Randall Cody Dannen
Force Multiplier Calculations For X-Ray Binaries And Active Galactic Nuclei, Randall Cody Dannen
UNLV Theses, Dissertations, Professional Papers, and Capstones
Motivated by the work done to explore the winds from hot stars (Lamers & Cassinelli 1999), we develop a method for self consistently calculating force multipliers for Type 1 and Type 2 active galactic nuclei (AGN), soft and hard start X-ray binaries (XRBs) spectral energy distributions (SEDs). We find that the ampflication to the radiation force can be as large as 100 even when the gas is highly ionized due to Fe and O ions. We discuss future efforts to incorporate these findings in magnetohydrodynamic simulations.
Optimization Of The Development Process For Air Sampling Filter Standards, Rajah Marie Mena
Optimization Of The Development Process For Air Sampling Filter Standards, Rajah Marie Mena
UNLV Theses, Dissertations, Professional Papers, and Capstones
Air monitoring is an important analysis technique in health physics. However, creating standards which can be used to calibrate detectors used in the analysis of the filters deployed for air monitoring can be challenging. The activity of a standard should be well understood, this includes understanding how the location within the filter affects the final surface emission rate. The purpose of this research is to determine the parameters which most affect uncertainty in an air filter standard and optimize these parameters such that calibrations made with them most accurately reflect the true activity contained inside. A deposition pattern was chosen …
Modeling Background Radiation Using Geochemical Data, Kara Marsac
Modeling Background Radiation Using Geochemical Data, Kara Marsac
UNLV Theses, Dissertations, Professional Papers, and Capstones
Aerial gamma ray surveys have many applications in geology and science in general, such as locating mining prospects, defining radioactive plumes, and detecting nuclear weapons. Unfortunately there is currently no simple way to separate the natural gamma radiation of soil and rocks from that of contaminants such as radioactive plumes. This project used geochemical data (uranium, potassium and thorium concentrations) collected from national databases, private companies, and the NURE (National Uranium Resource Evaluation) Survey, to create forward models of exposure rates measured by aerial gamma ray surveys. We developed these techniques using an area in north central Arizona known as …
Recycling And Reuse Of Radioactive Materials, Thomas Joseph O'Dou
Recycling And Reuse Of Radioactive Materials, Thomas Joseph O'Dou
UNLV Theses, Dissertations, Professional Papers, and Capstones
The Radiochemistry Program at the University of Nevada, Las Vegas (UNLV) has a Radiation Protection Program that was designed to provide students with the ability to safely work with radioactive materials in quantities that are not available in other academic environments. Requirements for continuous training and supervision make this unique program capable of turning out graduates that have an understanding of contamination and dose control techniques that complement their knowledge of the elements that they work with. The Program has also adopted a radionuclide recovery and reuse program that has provided materials from other universities, government agencies, and private companies …
Evaluation Of Low-Temperature Fluoride Routes To Synthesize Actinide Nitrides And Oxide Solid Solutions, Gunanda Waduge Chinthaka Silva
Evaluation Of Low-Temperature Fluoride Routes To Synthesize Actinide Nitrides And Oxide Solid Solutions, Gunanda Waduge Chinthaka Silva
UNLV Theses, Dissertations, Professional Papers, and Capstones
Actinide mononitrides have been considered as a possible nuclear fuel for the Generation-IV nuclear reactor systems. In the process of evaluating these actinide mononitrides as nuclear fuel, it is important to study different chemical and physical characteristics of these compounds. Synthesis of the materials is thus important. Carbothermic reduction is one of the techniques that have been used to synthesize actinide mononitrides. In this method, a mixture of actinide oxide such as UO 2 and excess carbon is heat treated at temperatures greater than 1700 °C under a nitrogen atmosphere. The technique is however not promising in synthesizing the actinide …