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Towards the Continuous Limit of Cluster Integrable Systems
None
Date:
October 25, 2013
Creator:
Franco, Sebastian; Galloni, Daniele & He, Yang-Hui
Object Type:
Article
System:
The UNT Digital Library
2013 LIDAR Campaign at Buena Vista Wind Farm: An Examination of Hill Speedup Flows
None
Date:
September 25, 2013
Creator:
Wharton, S; Qualley, G; Newman, J & Miller, W
Object Type:
Report
System:
The UNT Digital Library
Assessment of Proton Deflectometry for Exploding Wire Experiments
This project provides the first demonstration of the application of proton deflectometry for the diagnosis of electromagnetic field topology and current-carrying regions in Z-pinch plasma experiments. Over the course of this project several milestones were achieved. High-energy proton beam generation was demonstrated on the short-pulse high-intensity Leopard laser, (10 Joules in ~350 femtoseconds, and the proton beam generation was shown to be reproducible. Next, protons were used to probe the electromagnetic field structure of short circuit loads in order to benchmark the two numerical codes, the resistive-magnetohydrodynamics (MHD) code, Gorgon, and the hybrid particle-in-cell code, LSP for the interpretation of results. Lastly, the proton deflectometry technique was used to map the magnetic field structure of pulsed-power-driven plasma loads including wires and supersonic jets formed with metallic foils. Good agreement between the modeling and experiments has been obtained. The demonstrated technique holds great promise to significantly improve the understanding of current flow and electromagnetic field topology in pulsed power driven high energy density plasmas. Proton probing with a high intensity laser was for the first time implemented in the presence of the harsh debris and x-ray producing z-pinch environment driven by a mega-ampere-scale pulsed-power machine. The intellectual merit of the program …
Date:
September 25, 2013
Creator:
Beg, Farhat Nadeem
Object Type:
Report
System:
The UNT Digital Library
Characterization Of Sample HTF-13-13-128
Savannah River Remediation (SRR) has requested that Savannah River National Laboratory (SRNL) characterize a sample of Tank 13 in preparation for Sludge Batch 9 (SB9). A 200 mL sample of Tank 13 was received by SRNL on July 22, 2013 (Tank Farm sample ID HTF-13-13-128). Characterization of the sample to meet the requirements of the request is complete. Results include: visual observations; slurry and supernatant density; weight percent total and insoluble solids; supernatant characterization; total alpha, total beta, and several radionuclide analyses; and elemental analyses of the dried solids. The sample was very fluid. After settling overnight, there was a small layer of solids on the bottom of the sample container (a 250 mL HDPE bottle) with the remainder being clear supernatant. To better show the sludge solids relative to the overall sample, 25 mL of slurry was placed in a graduated cylinder and allowed to settle over a weekend (approximately 90 hours). The sludge layer was at the approximately 4 mL. The small visually observed quantity of insoluble solids was confirmed with a low weight percent insoluble solids of 0.94%.
Date:
September 25, 2013
Creator:
Pareizs, J. M.
Object Type:
Report
System:
The UNT Digital Library
Development of Parallel Computing Framework to Enhance Radiation Transport Code Capabilities for Rare Isotope Beam Facility Design
A parallel computing framework has been developed to use with general-purpose radiation transport codes. The framework was implemented as a C++ module that uses MPI for message passing. It is intended to be used with older radiation transport codes implemented in Fortran77, Fortran 90 or C. The module is significantly independent of radiation transport codes it can be used with, and is connected to the codes by means of a number of interface functions. The framework was developed and tested in conjunction with the MARS15 code. It is possible to use it with other codes such as PHITS, FLUKA and MCNP after certain adjustments. Besides the parallel computing functionality, the framework offers a checkpoint facility that allows restarting calculations with a saved checkpoint file. The checkpoint facility can be used in single process calculations as well as in the parallel regime. The framework corrects some of the known problems with the scheduling and load balancing found in the original implementations of the parallel computing functionality in MARS15 and PHITS. The framework can be used efficiently on homogeneous systems and networks of workstations, where the interference from the other users is possible.
Date:
September 25, 2013
Creator:
Kostin, Mikhail; Mokhov, Nikolai & Niita, Koji
Object Type:
Report
System:
The UNT Digital Library
DWPF Simulant CPC Studies For SB8
Prior to processing a Sludge Batch (SB) in the Defense Waste Processing Facility (DWPF), flowsheet studies using simulants are performed. Typically, the flowsheet studies are conducted based on projected composition(s). The results from the flowsheet testing are used to 1) guide decisions during sludge batch preparation, 2) serve as a preliminary evaluation of potential processing issues, and 3) provide a basis to support the Shielded Cells qualification runs performed at the Savannah River National Laboratory (SRNL). SB8 was initially projected to be a combination of the Tank 40 heel (Sludge Batch 7b), Tank 13, Tank 12, and the Tank 51 heel. In order to accelerate preparation of SB8, the decision was made to delay the oxalate-rich material from Tank 12 to a future sludge batch. SB8 simulant studies without Tank 12 were reported in a separate report.1 The data presented in this report will be useful when processing future sludge batches containing Tank 12. The wash endpoint target for SB8 was set at a significantly higher sodium concentration to allow acceptable glass compositions at the targeted waste loading. Four non-coupled tests were conducted using simulant representing Tank 40 at 110-146% of the Koopman Minimum Acid requirement. Hydrogen was generated during …
Date:
September 25, 2013
Creator:
Newell, J. D.
Object Type:
Report
System:
The UNT Digital Library
National Ignition Facility Dilation X-Ray Imager Diagnostic Instrumentation And Control System*
None
Date:
September 25, 2013
Creator:
Nelson, J. R.; Ayers, M. J.; Barrios, M. A.; Bell, P. M.; Bradley, D. K.; Collins, G. W. et al.
Object Type:
Article
System:
The UNT Digital Library
Planning Document for an NBSR Conversion Safety Analysis Report
The NIST Center for Neutron Research (NCNR) is a reactor-laboratory complex providing the National Institute of Standards and Technology (NIST) and the nation with a world-class facility for the performance of neutron-based research. The heart of this facility is the National Bureau of Standards Reactor (NBSR). The NBSR is a heavy water moderated and cooled reactor operating at 20 MW. It is fueled with high-enriched uranium (HEU) fuel elements. A Global Threat Reduction Initiative (GTRI) program is underway to convert the reactor to low-enriched uranium (LEU) fuel. This program includes the qualification of the proposed fuel, uranium and molybdenum alloy foil clad in an aluminum alloy, and the development of the fabrication techniques. This report is a planning document for the conversion Safety Analysis Report (SAR) that would be submitted to, and approved by, the Nuclear Regulatory Commission (NRC) before the reactor could be converted.This report follows the recommended format and content from the NRC codified in NUREG-1537, “Guidelines for Preparing and Reviewing Applications for the Licensing of Non-power Reactors,” Chapter 18, “Highly Enriched to Low-Enriched Uranium Conversions.” The emphasis herein is on the SAR chapters that require significant changes as a result of conversion, primarily Chapter 4, Reactor Description, …
Date:
September 25, 2013
Creator:
Diamond, D. J.; Baek, J.; Hanson, A. L.; Cheng, L. Y.; Brown, N. & Cuadra, A.
Object Type:
Report
System:
The UNT Digital Library
Radiation Leukemogenesis at Low Dose Rates
The major goals of this program were to study the efficacy of low dose rate radiation exposures for the induction of acute myeloid leukemia (AML) and to characterize the leukemias that are caused by radiation exposures at low dose rate. An irradiator facility was designed and constructed that allows large numbers of mice to be irradiated at low dose rates for protracted periods (up to their life span). To the best of our knowledge this facility is unique in the US and it was subsequently used to study radioprotectors being developed for radiological defense (PLoS One. 7(3), e33044, 2012) and is currently being used to study the role of genetic background in susceptibility to radiation-induced lung cancer. One result of the irradiation was expected; low dose rate exposures are ineffective in inducing AML. However, another result was completely unexpected; the irradiated mice had a very high incidence of hepatocellular carcinoma (HCC), approximately 50%. It was unexpected because acute exposures are ineffective in increasing HCC incidence above background. This is a potential important finding for setting exposure limits because it supports the concept of an 'inverse dose rate effect' for some tumor types. That is, for the development of some tumor …
Date:
September 25, 2013
Creator:
Weil, Michael & Ullrich, Robert
Object Type:
Report
System:
The UNT Digital Library
The Radiative Properties of Small Clouds: Multi-Scale Observations and Modeling
Warm, liquid clouds and their representation in climate models continue to represent one of the most significant unknowns in climate sensitivity and climate change. Our project combines ARM observations, LES modeling, and satellite imagery to characterize shallow clouds and the role of aerosol in modifying their radiative effects.
Date:
September 25, 2013
Creator:
Feingold, Graham & McComiskey, Allison
Object Type:
Report
System:
The UNT Digital Library
Safeguards Approaches for Black Box Processes or Facilities
The objective of this study is to determine whether a safeguards approach can be developed for “black box” processes or facilities. These are facilities where a State or operator may limit IAEA access to specific processes or portions of a facility; in other cases, the IAEA may be prohibited access to the entire facility. The determination of whether a black box process or facility is safeguardable is dependent upon the details of the process type, design, and layout; the specific limitations on inspector access; and the restrictions placed upon the design information that can be provided to the IAEA. This analysis identified the necessary conditions for safeguardability of black box processes and facilities.
Date:
September 25, 2013
Creator:
Diaz-Marcano, Helly; Gitau, Ernest TN; Hockert, John; Miller, Erin & Wylie, Joann
Object Type:
Report
System:
The UNT Digital Library
SRS SLUDGE BATCH QUALIFICATION AND PROCESSING; HISTORICAL PERSPECTIVE AND LESSONS LEARNED
This report provides a historical overview and lessons learned associated with the SRS sludge batch (SB) qualification and processing programs. The report covers the framework of the requirements for waste form acceptance, the DWPF Glass Product Control Program (GPCP), waste feed acceptance, examples of how the program complies with the specifications, an overview of the Startup Program, and a summary of continuous improvements and lessons learned. The report includes a bibliography of previous reports and briefings on the topic.
Date:
September 25, 2013
Creator:
Cercy, M.; Peeler, D. & Stone, M.
Object Type:
Report
System:
The UNT Digital Library
Strategies for Voltage Control and Transient Stability Assessment
As wind generation grows, its influence on power system performance will becoming increasingly noticeable. Wind generation di#11;ffers from traditional forms of generation in numerous ways though, motivating the need to reconsider the usual approaches to power system assessment and performance enhancement. The project has investigated the impact of wind generation on transient stability and voltage control, identifying and addressing issues at three distinct levels of the power system: 1) at the device level, the physical characteristics of wind turbine generators (WTGs) are quite unlike those of synchronous machines, 2) at the wind-farm level, the provision of reactive support is achieved through coordination of numerous dissimilar devices, rather than straightforward generator control, and 3) from a systems perspective, the location of wind-farms on the sub-transmission network, coupled with the variability inherent in their power output, can cause complex voltage control issues. The project has sought to develop a thorough understanding of the dynamic behaviour of type-3 WTGs, and in particular the WECC generic model. The behaviour of such models is governed by interactions between the continuous dynamics of state variables and discrete events associated with limits. It was shown that these interactions can be quite complex, and may lead to switching …
Date:
September 25, 2013
Creator:
Hiskens, Ian A.
Object Type:
Report
System:
The UNT Digital Library
Unveiling the Nature of the Unidentified Gamma-ray Sources V: Analysis of the Radio Candidates with the Kernel Density Estimation
None
Date:
September 25, 2013
Creator:
Massaro, F.; D'Abrusco, R.; Paggi, A.; Masetti, N.; Giroletti, M.; Tosti, G. et al.
Object Type:
Article
System:
The UNT Digital Library
Modeling of a Slanted-Hole Collimator in a Compact Endocavity Gamma Camera
N/A
Date:
August 25, 2013
Creator:
Cui, Y.; Karmuda, M.; Lall, T.; Ionson, J.; Camarda, G.; Hossain, A. et al.
Object Type:
Article
System:
The UNT Digital Library
New Manufacturing Method for Paper Filler and Fiber Material
The use of fillers in printing and writing papers has become a prerequisite for competing in a global market to reduce the cost of materials. Use of calcium carbonates (ranging from 18% to 30%) as filler is a common practice in the paper industry but the choices of fillers for each type of papers vary widely according to its use. The market for uncoated digital printing paper is one that continues to introduce exciting growth projections. and it is important to understand the effect that new manufacturing methods of calcium carbonates have on the energy efficiency and paper production. Research conducted under this award showed that the new fiber filler composite material has the potential to increase the paper filler content by up to 5% without losing mechanical properties. Benefits of the technology can be summarized as follows for a 1% filler increase per metric ton of paper produced: (i) production cost savings over $12, (ii) Energy savings of 100,900 btu, (iii) CO{sub 2} emission savings of 33 lbs, and additional savings for wood preparation, pulping, recovery of 203593 btu with a 46lbs of CO{sub 2} emission savings per 1% filler increase. In addition the technology has the potential to …
Date:
August 25, 2013
Creator:
Doelle, Klaus
Object Type:
Report
System:
The UNT Digital Library
Post-growth Annealing of CdZnTe crystals: an analysis of defect-structures and opto-electronic properties
N/A
Date:
August 25, 2013
Creator:
Yang, G.; Bolotnikov, A. E.; Fochuk, P. M.; Camarda, G. S.; Hossain, A.; Roy, U. et al.
Object Type:
Article
System:
The UNT Digital Library
Side-surface passivation effect on the electrical properties of metal-CdZnTe-metal structures
N/A
Date:
August 25, 2013
Creator:
A., Bolotnikov; Sklyarchuk, V.; Fochuk, P.; Zakharuk, Z.; Grill, R.; Kutny, V. Rybka, A. et al.
Object Type:
Article
System:
The UNT Digital Library
241-SY Tank Farm Construction Extent of Condition Review for Tank Integrity
This report provides the results of an extent of condition construction history review for tanks 241-SY-101, 241-SY-102, and 241-SY-103. The construction history of the 241-SY tank farm has been reviewed to identify issues similar to those experienced during tank 241-AY-102 construction. Those issues and others impacting integrity are discussed based on information found in available construction records, using tank 241-AY-102 as the comparison benchmark. In the 241-SY tank farm, the third DST farm constructed, refractory quality and stress relief were improved, while similar tank and liner fabrication issues remained.
Date:
July 25, 2013
Creator:
Barnes, Travis J.; Boomer, Kayle D.; Gunter, Jason R. & Venetz, Theodore J.
Object Type:
Report
System:
The UNT Digital Library
Flammability Control In A Nuclear Waste Vitrification System
The Defense Waste Processing Facility at the Savannah River Site processes high-level radioactive waste from the processing of nuclear materials that contains dissolved and precipitated metals and radionuclides. Vitrification of this waste into borosilicate glass for ultimate disposal at a geologic repository involves chemically modifying the waste to make it compatible with the glass melter system. Pretreatment steps include removal of excess aluminum by dissolution and washing, and processing with formic and nitric acids to: 1) adjust the reduction-oxidation (redox) potential in the glass melter to reduce radionuclide volatility and improve melt rate; 2) adjust feed rheology; and 3) reduce by steam stripping the amount of mercury that must be processed in the melter. Elimination of formic acid in pretreatment has been studied to eliminate the production of hydrogen in the pretreatment systems, which requires nuclear grade monitoring equipment. An alternative reductant, glycolic acid, has been studied as a substitute for formic acid. However, in the melter, the potential for greater formation of flammable gases exists with glycolic acid. Melter flammability is difficult to control because flammable mixtures can be formed during surges in offgases that both increase the amount of flammable species and decrease the temperature in the vapor …
Date:
July 25, 2013
Creator:
Zamecnik, John R.; Choi, Alexander S.; Johnson, Fabienne C.; Miller, Donald H.; Lambert, Daniel P.; Stone, Michael E. et al.
Object Type:
Article
System:
The UNT Digital Library
INDEPENDENT CONFIRMATORY SURVEY SUMMARY AND RESULTS FOR THE FORD NUCLEAR REACTOR, ANN ARBOR, MICHIGAN
At the NRC�s request, ORAU conducted confirmatory surveys of the FNR during the period of December 4 through 6, 2012. The survey activities included visual inspections and measurement and sampling activities. Confirmatory activities also included the review and assessment of UM�s project documentation and methodologies. Surface scans identified elevated activity in two areas. The first area was on a wall outside of Room 3103 and the second area was in the southwest section on the first floor. The first area was remediated to background levels. However, the second area was due to gamma shine from a neighboring source storage area. A retrospective analysis of UM�s FSS data shows that for the SUs investigated by the ORAU survey team, UM met the survey requirements set forth in the FSSP. The total mean surface activity values were directly compared with the mean total surface activity reported by UM. Mean surface activity values determined by UM were within two standard deviations of the mean determined by ORAU. Additionally, all surface activity values were less than the corresponding gross beta DCGLW. Laboratory analysis of the soil showed that COC concentrations were less than the respective DCGLW values. For the inter-lab comparison, the DER was …
Date:
July 25, 2013
Creator:
Altic, Nick A.
Object Type:
Report
System:
The UNT Digital Library
Numerical Studies of Collective Phenomena in Two-Dimensional Electron and Cold Atom Systems
Numerical calculations were carried out to investigate a number of outstanding questions in both two-dimensional electron and cold atom systems. These projects aimed to increase our understanding of the properties of and prospects for non-Abelian states in quantum Hall matter.
Date:
July 25, 2013
Creator:
Rezayi, Edward
Object Type:
Report
System:
The UNT Digital Library
The Origin of Mass
None
Date:
July 25, 2013
Creator:
Boyle, P.; Buchoff, M.; Christ, N.; Izubuchi, T.; Jung, C.; Luu, T. et al.
Object Type:
Article
System:
The UNT Digital Library
Size Distribution and Oxide Thickness of Uranium Micro-Spheres
None
Date:
July 25, 2013
Creator:
Siekhaus, W J & Teslich, N E
Object Type:
Report
System:
The UNT Digital Library