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Pressure-induced Breaking of Equilibrium Flux Surfaces in the W7AS Stellarator

Description: Calculations are presented for two shots in the W7AS stellarator which differ only in the magnitude of the current in the divertor control coil, but have very different values of experimentally attainable β (<β> ≈ 2.7% versus <β> ≈ 1.8%). Equilibrium calculations find that a region of chaotic magnetic field line trajectories fills approximately the outer 1/3 of the cross-section in each of these configurations. The field lines in the stochastic region are calculated to behave as if the flux surfaces are broken only locally near the outer midplane and are preserved elsewhere. The calculated magnetic field line diffusion coefficients in the stochastic regions for the two shots are consistent with the observed differences in the attainable β, and are also consistent with the differences in the reconstructed pressure profiles.
Date: April 24, 2007
Creator: A. Reiman, M.C. Zarnstorff, D. Monticello, A. Weller, J. Geiger, and the W7-AS Team
Partner: UNT Libraries Government Documents Department
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Evaluation of the Cask Transportation Facility Modifications (CTFM) compliance to DOE order 6430.1A Project A.5 and A.6

Description: This report was prepared to evaluate the compliance of CTFM to DOE Order 6430.1A. This document presents the results of an evaluation that was performed to assess compliance of the K West (KW) Cask Transportation Facility Modifications (CTFM) designs against applicable requirements of Department of Energy (DOE) Order 6430.1 A, General Design Criteria. This evaluation was grouped under two categories described as Cask Loadout System (CLS) and Cranes/Other Modifications.
Date: April 24, 2000
Creator: ARD, K.E.
Partner: UNT Libraries Government Documents Department
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LEEM investigations of clean surfaces driven by energetic ion beams

Description: The original purpose of this award was to use low&#8208;energy electron microscopy (LEEM) to explore the dynamics of surfaces of clean single crystal surfaces when driven by a beam of energetic ions. The goal was to understand the nanoscience of hyperthermal growth, surface erosion by sublimation and irradiation, operation of surface sinks in irradiated materials, diffusion on driven surfaces, and the creation of structural patterns. This project was based on a novel LEEM system constructed by C. P. Flynn, which provided real&#8208;time imaging of surface dynamics by scattering low energy electrons. With the passing of Prof. Flynn in late 2011, this project was completed under a slightly different scope by constructing a low&#8208;energy, inelastic electron scattering (�EELS�) instrument. Consistent with Flynn�s original objectives for his LEEM system, this device probes the dynamics of crystal surfaces. However the measurements are not carried out in real time, but instead are done in the frequency domain, through the energy lost from the probe electrons. The purpose of this device is to study the collective bosonic excitations in a variety of materials, including high temperature superconductors, topological insulators, carbon allotropes including (but not limited to) graphene, etc. The ultimate goal here is to identify the bosons that mediate interactions in these and other materials, with hopes of shedding light on the origin of many exotic phenomena including high temperature superconductivity. We completed the construction of a low&#8208;energy EELS system that operates with an electron kinetic energy of 7 - 10 eV. With this instrument now running, we hope to identify, among other things, the bosons that mediate pairing in high temperature superconductors. Using this instrument, we have already made our first discovery. Studying freshly cleaved single crystals of Bi{sub 2}Se{sub 3}, which is a topological insulator, we have observed a surface excitation at an …
Date: April 24, 2013
Creator: Abbamonte, Peter M.
Partner: UNT Libraries Government Documents Department

Oral History Interview with Rula Walid Bibi, April 24, 2011

Description: Interview with Rula Walid Bibi, Palestinian-born immigrant to Plano, Texas, for the DFW Metroplex Immigrants Oral History Project. The interview includes Bibi's personal experience with discrimination of Palestinians in the Middle East, childhood in Kuwait City, education at the University of Kuwait and Midwestern State University, family experiences during the First Gulf War and circumstances surrounding her immigration to Texas in 1990, thoughts on religion, experiences as a single mother as well as experiences of living in Wichita Falls, Dallas, Richardson, Garland, and Plano. Bibi talks about her first impressions of the U.S., her career in medical technologies, her marriage to an American man and his conversion to Islam, her involvement with political organizations, and thoughts on American education and foreign policy.
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: April 24, 2011
Creator: Abigail, R. Matthew & Bibi, Rula Walid
Partner: UNT Oral History Program
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Recommended technical specifications for first generation test surface and subsurface markers

Description: Federal regulations and Rockwell Hanford Operations (Rockwell) planning documents require that radioactive waste sites disposed in-place be permanently marked. A number of technical studies have addressed the materials to be used for permanent markers as well as the design configurations. Criteria and standards for markers have also been prepared and issued in draft form. The next step in marker development requires laboratory and field testing of prototype markers. This document provides design specifications for the first generation surface and subsurface markers. At the conclusion of testing activities, definitive specifications can be prepared. Included herein are specifications for marker placement, marker materials, marker configuration and dimensions and marker messages. This document presents specifications only and does not provide rationale or justification for the specifications. Such rationale and justification is available in referenced documents.
Date: April 24, 1984
Creator: Adams, M. R.
Partner: UNT Libraries Government Documents Department
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Estimate of Hazard Produced by Accidental Release of Gaseous Fission Products from an ORR Fused Salt Capsule Experiment

Description: An accidental release of gaseous fission products from an ORR fused salt capsule, containing 26 mg. of U/sup 235/, was postulated and the resuiting hazard estimated by calculating the maximum external and internal dose an individual could receive from exposure to the gaseous fission products and their decay products. Assuming all the contained gaseous fission produets are released, the resulting external and internal dosc, to organs other than the thyroid, arc insignificant. The dose to the thyroid by radioiodine is considered to be significant. By retaining at least 90% of the iodine isotopes in the experiment system through use of an iodine trap, a large reduction in both the external whole body and internal thyroid doses may be achieved. Therefore, assuming an iodine trap is utilized, it appears that the consequences of am accidental gaseous fission product release from an ORR fused salt capsule experiment would not be serious. (auth)
Date: April 24, 1959
Creator: Adams, R. E. & Browning, W. E.
Partner: UNT Libraries Government Documents Department
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Development of a video-based slurry sensor for on-line ash analysis. Second quarterly technical progress report, January 1, 1995--March 31, 1995

Description: Automatic control of fine coal cleaning circuits has traditionally been limited by the lack of sensors for on-line ash analysis. Although several nuclear-based analyzers are available, none have seen widespread acceptance. This is largely due to the fact that nuclear sensors are expensive and tend to be influenced by changes in seam type and pyrite content. Recently, researchers at VPI&SU have developed an optical sensor for phosphate analysis. The sensor uses image processing technology to analyze video images of phosphate ore. It is currently being used by Texasgulf for off-line analysis of dry flotation concentrates. The primary advantages of optical sensors over nuclear sensors are that they are significantly cheaper, are not subject to measurement variations due to changes in high atomic number minerals, are inherently safer and require no special radiation permitting. Purpose of this work is to apply the knowledge gained in the development of an optical phosphate analyzer to the development of an on-line ash analyzer for fine coal slurries. During the past quarter, tests were performed on two prototype sample presentation systems for the optical analyzer. Preliminary results indicate that the flow of slurry past the camera lens is too consistent to provide reliable results. A third option for sampel presentation is being explored.
Date: April 24, 1995
Creator: Adel, G. T. & Luttrell, G. H.
Partner: UNT Libraries Government Documents Department
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Stress-Relief Displacements Induced by Drilling--Applications to Holographic Measurements of in Situ Stress

Description: The holographic stressmeter is an instrument which has been developed at Caltech to allow determination of the complete stress tensor from in situ borehole measurements. The stressmeter uses double-exposure holographic interferometry to record the displacements induced by the drilling of a small sidehole into the borehole wall. The local stresses, which are the result of the far-field stresses, concentrated at the borehole, cause deformation of the surface of the borehole wall in the vicinity of the sidehole. The first part of this study uses a thin infinite elastic plate subjected to plane stress at infinity to model the displacements at the borehole wall. However, the existence of some holograms which were difficult to model closely led us to examine the validity of this model. In order to investigate the problem further, we performed a two-dimensional finite element analysis for an elastic box with a terminated hole. We varied the dimensions of the hole to see what effect the radius and depth of the hole might have on the displacements. The plate model predicts that the depth of the hole should have no effect on the horizontal components of displacement, but the finite element results show that the magnitude of both components of the displacement depends on the depth of the sidehole. After considering these results, we developed a new model for the analysis of stress-relief displacements, following the work of Youngdahl and Sternberg (1965). For holes with a depth-to-diameter ratio greater than unity, the simple plane stress elastic plate solution breaks down and does not adequately model the displacements at the surface of the body and near the hole. Since these are the areas most critical to calculate accurately with the holographic technique, the revised model does a better job of fitting the observed data.
Date: April 24, 1992
Creator: Ahrens, T. J. & Smither, C. L.
Partner: UNT Libraries Government Documents Department
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Stress-Relief Displacements Induced by Drilling--Applications to Holographic Measurements of in Situ Stress. Final Technical Report, August 15, 1988--August 14, 1990

Description: The holographic stressmeter is an instrument which has been developed at Caltech to allow determination of the complete stress tensor from in situ borehole measurements. The stressmeter uses double-exposure holographic interferometry to record the displacements induced by the drilling of a small sidehole into the borehole wall. The local stresses, which are the result of the far-field stresses, concentrated at the borehole, cause deformation of the surface of the borehole wall in the vicinity of the sidehole. The first part of this study uses a thin infinite elastic plate subjected to plane stress at infinity to model the displacements at the borehole wall. However, the existence of some holograms which were difficult to model closely led us to examine the validity of this model. In order to investigate the problem further, we performed a two-dimensional finite element analysis for an elastic box with a terminated hole. We varied the dimensions of the hole to see what effect the radius and depth of the hole might have on the displacements. The plate model predicts that the depth of the hole should have no effect on the horizontal components of displacement, but the finite element results show that the magnitude of both components of the displacement depends on the depth of the sidehole. After considering these results, we developed a new model for the analysis of stress-relief displacements, following the work of Youngdahl and Sternberg (1965). For holes with a depth-to-diameter ratio greater than unity, the simple plane stress elastic plate solution breaks down and does not adequately model the displacements at the surface of the body and near the hole. Since these are the areas most critical to calculate accurately with the holographic technique, the revised model does a better job of fitting the observed data.
Date: April 24, 1992
Creator: Ahrens, T. J. & Smither, C. L.
Partner: UNT Libraries Government Documents Department
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Intelligent Extruder

Description: ''Intelligent Extruder'' described in this report is a software system and associated support services for monitoring and control of compounding extruders to improve material quality, reduce waste and energy use, with minimal addition of new sensors or changes to the factory floor system components. Emphasis is on process improvements to the mixing, melting and de-volatilization of base resins, fillers, pigments, fire retardants and other additives in the :finishing'' stage of high value added engineering polymer materials. While GE Plastics materials were used for experimental studies throughout the program, the concepts and principles are broadly applicable to other manufacturers materials. The project involved a joint collaboration among GE Global Research, GE Industrial Systems and Coperion Werner & Pleiderer, USA, a major manufacturer of compounding equipment. Scope of the program included development of a algorithms for monitoring process material viscosity without rheological sensors or generating waste streams, a novel detection scheme for rapid detection of process upsets and an adaptive feedback control system to compensate for process upsets where at line adjustments are feasible. Software algorithms were implemented and tested on a laboratory scale extruder (50 lb/hr) at GE Global Research and data from a production scale system (2000 lb/hr) at GE Plastics was used to validate the monitoring and detection software. Although not evaluated experimentally, a new concept for extruder process monitoring through estimation of high frequency drive torque without strain gauges is developed and demonstrated in simulation. A plan to commercialize the software system is outlined, but commercialization has not been completed.
Date: April 24, 2003
Creator: AlperEker; Giammattia, Mark; Houpt, Paul; Kumar, Aditya; Montero, Oscar; Shah, Minesh et al.
Partner: UNT Libraries Government Documents Department
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ION EXCHANGE PERFORMANCE OF TITANOSILICATES, GERMANATES AND CARBON NANOTUBES

Description: This report presents a summary of testing the affinity of titanosilicates (TSP), germanium-substituted titanosilicates (Ge-TSP) and multiwall carbon nanotubes (MWCNT) for lanthanide ions in dilute nitric acid solution. The K-TSP ion exchanger exhibited the highest affinity for lanthanides in dilute nitric acid solutions. The Ge-TSP ion exchanger shows promise as a material with high affinity, but additional tests are needed to confirm the preliminary results. The MWCNT exhibited much lower affinities than the K-TSP in dilute nitric acid solutions. However, the MWCNT are much more chemically stable to concentrated nitric acid solutions and, therefore, may candidates for ion exchange in more concentrated nitric acid solutions. This technical report serves as the deliverable documenting completion of the FY13 research milestone, M4FT-13SR0303061 – measure actinide and lanthanide distribution values in nitric acid solutions with sodium and potassium titanosilicate materials.
Date: April 24, 2013
Creator: Alsobrook, A. & Hobbs, D.
Partner: UNT Libraries Government Documents Department
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Testing the COncept of Drift Shadow with X-Ray Absorption Imaging

Description: X-ray absorption imaging experiments and measurements of inflow and outflow distribution provide quantitative and vistial evidence for capillary diversion around a drift and a drift-shadow effect. Test cells were constructed from volcanic tuff with either in-plane (one fracture parallel to the face of the test cell) or multi-fracture (with a grid of fractures perpendicular to the test cell) systems. Tracer solutions were dripped in the fractures at ports along the top of the test cell. Discharge along the bottom boundary and in the drift was monitored. Variables included flow rate and fracture aperture. X-ray absorption imaging allowed for visualization of flow paths through the system. Evidence for capillary diversion and drift shadow include: (1) very small (&lt; 1 %,of inflow in most cases) measured discharge into the drift, (2) discharge less than expected under the drift and discharge greater than expected just beyond the drift, and (3) visualization of the tracer-solution flow path from above the drift, around the drift, and shedding beyond the drift. However, tracer was also observed in a natural fracture under the drift in one system. It is unclear whether these high concentrations are due to diversion around the drift and back under the drift or capillary spreading along the bottom boundary of the test cell. Future experiments will focus on using samples collected directly from Yucca Mountain and minimizing the capillary barrier effects along the lower boundary of the test cells. The implementation of the drift shadow effect, as supported by these experiments, could impact performance of the proposed Yucca Mountain repository.
Date: April 24, 2006
Creator: Altman, S.J.; Forsberg, A.; Peplinski, W. & Ho, CK.
Partner: UNT Libraries Government Documents Department
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Women in the United States Congress

Description: This report identifies women who have served as U.S. Senators or Representatives. It notes their party affiliation, the States they have represented, the dates of their appointment or election, the length of their service, their committee assignments, and their service in committee chairmanships.
Date: April 24, 1985
Creator: Amer, Mildred L.
Partner: UNT Libraries Government Documents Department
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