TRITIUM UNCERTAINTY ANALYSIS FOR SURFACE WATER SAMPLES AT THE SAVANNAH RIVER SITE (open access)

TRITIUM UNCERTAINTY ANALYSIS FOR SURFACE WATER SAMPLES AT THE SAVANNAH RIVER SITE

Radiochemical analyses of surface water samples, in the framework of Environmental Monitoring, have associated uncertainties for the radioisotopic results reported. These uncertainty analyses pertain to the tritium results from surface water samples collected at five locations on the Savannah River near the U.S. Department of Energy's Savannah River Site (SRS). Uncertainties can result from the field-sampling routine, can be incurred during transport due to the physical properties of the sample, from equipment limitations, and from the measurement instrumentation used. The uncertainty reported by the SRS in their Annual Site Environmental Report currently considers only the counting uncertainty in the measurements, which is the standard reporting protocol for radioanalytical chemistry results. The focus of this work is to provide an overview of all uncertainty components associated with SRS tritium measurements, estimate the total uncertainty according to ISO 17025, and to propose additional experiments to verify some of the estimated uncertainties. The main uncertainty components discovered and investigated in this paper are tritium absorption or desorption in the sample container, HTO/H{sub 2}O isotopic effect during distillation, pipette volume, and tritium standard uncertainty. The goal is to quantify these uncertainties and to establish a combined uncertainty in order to increase the scientific depth …
Date: July 31, 2012
Creator: Atkinson, R.
Object Type: Book
System: The UNT Digital Library
District of Columbia: A Brief Review of Provisions in District of Columbia Appropriations Acts Restricting the Funding of Abortion Services (open access)

District of Columbia: A Brief Review of Provisions in District of Columbia Appropriations Acts Restricting the Funding of Abortion Services

This report provides A Brief Review of Provisions in District of Columbia Appropriations Acts Restricting the Funding of Abortion Services in the District of Columbia.
Date: July 31, 2012
Creator: Boyd, Eugene
Object Type: Report
System: The UNT Digital Library
Transport and Installation of the Dark Energy Survey CCD Imager (open access)

Transport and Installation of the Dark Energy Survey CCD Imager

None
Date: July 31, 2012
Creator: Derylo, Greg; Chi, Edward; Diehl, H.Thomas; Estrada, Juan; Flaugher, Brenna & Schultz, Ken
Object Type: Article
System: The UNT Digital Library
Neutron Production Using a Pyroelectric Driven Target Coupled with a Gated Field Ionization Source (open access)

Neutron Production Using a Pyroelectric Driven Target Coupled with a Gated Field Ionization Source

None
Date: July 31, 2012
Creator: Ellsworth, J L; Tang, V; Falabella, S; Naranjo, B & Putterman, S
Object Type: Article
System: The UNT Digital Library
Selective Extraction of Uranium from Liquid or Supercritical Carbon Dioxide (open access)

Selective Extraction of Uranium from Liquid or Supercritical Carbon Dioxide

Current liquid-liquid extraction processes used in recycling irradiated nuclear fuel rely on (1) strong nitric acid to dissolve uranium oxide fuel, and (2) the use of aliphatic hydrocarbons as a diluent in formulating the solvent used to extract uranium. The nitric acid dissolution process is not selective. It dissolves virtually the entire fuel meat which complicates the uranium extraction process. In addition, a solvent washing process is used to remove TBP degradation products, which adds complexity to the recycling plant and increases the overall plant footprint and cost. A liquid or supercritical carbon dioxide (l/sc -CO2) system was designed to mitigate these problems. Indeed, TBP nitric acid complexes are highly soluble in l/sc -CO2 and are capable of extracting uranium directly from UO2, UO3 and U3O8 powders. This eliminates the need for total acid dissolution of the irradiated fuel. Furthermore, since CO2 is easily recycled by evaporation at room temperature and pressure, it eliminates the complex solvent washing process. In this report, we demonstrate: (1) A reprocessing scheme starting with the selective extraction of uranium from solid uranium oxides into a TBP-HNO3 loaded Sc-CO2 phase, (2) Back extraction of uranium into an aqueous phase, and (3) Conversion of recovered purified …
Date: July 31, 2012
Creator: Farawila, Anne F.; O'Hara, Matthew J.; Wai, Chien M.; Taylor, Harry Z. & Liao, Yu-Jung
Object Type: Report
System: The UNT Digital Library
Drought in the United States: Causes and Issues for Congress (open access)

Drought in the United States: Causes and Issues for Congress

This report provides information about the Causes and Issues for Congress on Drought in the United States. Drought has extended across two-thirds of the United States and had adversely affected agricultural producers.
Date: July 31, 2012
Creator: Folger, Peter; Cody, Betsy A. & Carter, Nicole T.
Object Type: Report
System: The UNT Digital Library
EVALUATION OF ALTERNATIVE FILTER MEDIA FOR THE ROTARY MICROFILTER, PHASE 2 (open access)

EVALUATION OF ALTERNATIVE FILTER MEDIA FOR THE ROTARY MICROFILTER, PHASE 2

Testing was conducted at the Savannah River National Laboratory (SRNL) to investigate filter membrane performance in an effort to increase rotary microfilter (RMF) throughput. Membranes were tested in the SpinTek Filtration, Inc. Static Test Cell (STC), which permitted quick and easy testing of several different membranes. Testing consisted of 100 hours tests with two different slurry feeds, based on recommendations from the phase 1 testing. One feed contained Monosodium Titanate (MST) solids in a simulated salt solution. The other feed contained simulated sludge batch 6 (SB6) solids in a simulated salt solution. Five membranes were tested, one each from filter manufactures Pall and Porvair and three from the Oak Ridge National Laboratory (ORNL). The membrane from Pall is the current membrane used on the latest generation RMF. The Porvair membrane performed well in previous STC tests as well as one of the ORNL membranes. The other two membranes from ORNL were recently developed and not available for the previous STC test. The results indicate that the Porvair filter performed best with the MST slurry and the ORNL SVB6-1B filter performed best with the SB6 slurry. Difficulty was encountered with the ORNL filters due to their dimensional thickness, which was greater …
Date: July 31, 2012
Creator: Fowley, M.
Object Type: Report
System: The UNT Digital Library
GAS-HYBRID SOURCE 14C-AMS:Application to terrestrial ecosystem, biological, and environmental research (open access)

GAS-HYBRID SOURCE 14C-AMS:Application to terrestrial ecosystem, biological, and environmental research

None
Date: July 31, 2012
Creator: Guilderson, T P
Object Type: Report
System: The UNT Digital Library
Sediment Transport Modeling of Channel Scale Geomorphic Processes (open access)

Sediment Transport Modeling of Channel Scale Geomorphic Processes

This report investigated the use of two-dimensional (2D) modeling strategy to predict channel adjustment in the lower San Antonio River in response to a range of flood magnitudes.
Date: July 31, 2012
Creator: Haschenburger, Judith K.
Object Type: Report
System: The Portal to Texas History
Fabrication of Pd/Pd-Alloy Films by Surfactant Induced Electroless Plating for Hydrogen Separation from Advanced Coal Gasification Processes (open access)

Fabrication of Pd/Pd-Alloy Films by Surfactant Induced Electroless Plating for Hydrogen Separation from Advanced Coal Gasification Processes

Dense Pd, Pd-Cu and Pd-Ag composite membranes on microporous stainless steel substrate (MPSS) were fabricated by a novel electroless plating (EP) process. In the conventional Pd-EP process, the oxidation-reduction reactions between Pd-complex and hydrazine result in an evolution of NH{sub 3} and N{sub 2} gas bubbles. When adhered to the substrate surface and in the pores, these gas bubbles hinder uniform Pd-film deposition which results in dendrite growth leading to poor film formation. This problem was addressed by introducing cationic surfactant in the electroless plating process known as surfactant induced electroless plating (SIEP). The unique features of this innovation provide control of Pd-deposition rate, and Pd-grain size distribution. The surfactant molecules play an important role in the EP process by tailoring grain size and the process of agglomeration by removing tiny gas bubbles through adsorption at the gas-liquid interface. As a result surfactant can tailor a nanocrystalline Pd, Cu and Ag deposition in the film resulting in reduced membrane film thickness. Also, it produces a uniform, agglomerated film structure. The Pd-Cu and Pd-Ag membranes on MPSS support were fabricated by sequential deposition using SIEP method. The pre- and post-annealing characterizations of these membranes (Pd, Pd-Cu and Pd-Ag on MPSS substrate) …
Date: July 31, 2012
Creator: Ilias, Shamsuddin & Kumar, Dhananjay
Object Type: Report
System: The UNT Digital Library
A Staged Muon-Based Neutrino and Collider Physics Program (open access)

A Staged Muon-Based Neutrino and Collider Physics Program

None
Date: July 31, 2012
Creator: Kaplan, Daniel M.
Object Type: Article
System: The UNT Digital Library
Subtask 1.8 - Investigation of Improved Conductivity and Proppant Applications in the Bakken Formation (open access)

Subtask 1.8 - Investigation of Improved Conductivity and Proppant Applications in the Bakken Formation

Given the importance of hydraulic fracturing and proppant performance for development of the Bakken and Three Forks Formations within the Williston Basin, a study was conducted to evaluate the key factors that may result in conductivity loss within the reservoirs. Various proppants and reservoir rock cores were exposed to several different fracturing and formation fluids at reservoir conditions. The hardness of the rock cores and the strength of the proppants were evaluated prior to and following fluid exposure. In addition, the conductivity of various proppants, as well as formation embedment and spalling, was evaluated at reservoir temperatures and pressures using actual reservoir rock cores. The results of this work suggest that certain fluids may affect both rock and proppant strength, and therefore, fluid exposure needs to be considered in the field. In addition, conductivity decreases within the Bakken Formation appear to be a function of a variety of factors, including proppant and rock strength, as well as formation embedment and spalling. The results of this study highlight the need for advanced conductivity testing, coupled with quantification of formation embedment and spalling. Given the importance of proppant performance on conductivity loss and, ultimately, oil recovery, better understanding the effects of these …
Date: July 31, 2012
Creator: Kurz, Bethany; Schmidt, Darren; Beddoe, Steven Smith Christopher; Lindeman, Corey & Mibeck, Blaise
Object Type: Report
System: The UNT Digital Library
HB-LINE ANION EXCHANGE PURIFICATION OF AFS-2 PLUTONIUM FOR MOX (open access)

HB-LINE ANION EXCHANGE PURIFICATION OF AFS-2 PLUTONIUM FOR MOX

Non-radioactive cerium (Ce) and radioactive plutonium (Pu) anion exchange column experiments using scaled HB-Line designs were performed to investigate the feasibility of using either gadolinium nitrate (Gd) or boric acid (B as H{sub 3}BO{sub 3}) as a neutron poison in the H-Canyon dissolution process. Expected typical concentrations of probable impurities were tested and the removal of these impurities by a decontamination wash was measured. Impurity concentrations are compared to two specifications - designated as Column A or Column B (most restrictive) - proposed for plutonium oxide (PuO{sub 2}) product shipped to the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). Use of Gd as a neutron poison requires a larger volume of wash for the proposed Column A specification. Since boron (B) has a higher proposed specification and is more easily removed by washing, it appears to be the better candidate for use in the H-Canyon dissolution process. Some difficulty was observed in achieving the Column A specification due to the limited effectiveness that the wash step has in removing the residual B after ~4 BV's wash. However a combination of the experimental 10 BV's wash results and a calculated DF from the oxalate precipitation process yields an overall DF sufficient …
Date: July 31, 2012
Creator: Kyser, E. A. & King, W. D.
Object Type: Report
System: The UNT Digital Library
Appropriations: CRS Experts (open access)

Appropriations: CRS Experts

None
Date: July 31, 2012
Creator: Lake, Jennifer E.
Object Type: Report
System: The UNT Digital Library
Recommended Tritium Oxide Deposition Velocity For Use In Savannah River Site Safety Analyses (open access)

Recommended Tritium Oxide Deposition Velocity For Use In Savannah River Site Safety Analyses

This report documents the results of examining the deposition velocity of water to forests, the residence time of HTO in forests, and the relation between deposition velocity and residence time with specific consideration given to the topography and experimental work performed at SRS. A simple mechanistic model is used to obtain plausible deposition velocity and residence time values where experimental data are not available and recommendations are made for practical application in a safety analysis model.
Date: July 31, 2012
Creator: Lee, P. L.; Murphy, C. E.; Viner, B. J. & Hunter, C. H.
Object Type: Report
System: The UNT Digital Library
Roll-to-Roll Solution-Processible Small-Molecule OLEDs (open access)

Roll-to-Roll Solution-Processible Small-Molecule OLEDs

The objective of this program is to develop key knowledge and make critical connections between technologies needed to enable low-cost manufacturing of OLED lighting products. In particular, the program was intended to demonstrate the feasibility of making high performance Small-Molecule OLEDs (SM-OLED) using a roll-to-roll (R2R) wet-coating technique by addressing the following technical risks (1) Whether the wet-coating technique can provide high performance OLEDs, (2) Whether SM-OLED can be made in a R2R manner, (3) What are the requirements for coating equipment, and (4) Whether R2R OLEDs can have the same performance as the lab controls. The program has been managed and executed according to the Program Management Plan (PMP) that was first developed at the beginning of the program and further revised accordingly as the program progressed. Significant progress and risk reductions have been accomplished by the end of the program. Specific achievements include: (1) Demonstrated that wet-coating can provide OLEDs with high LPW and long lifetime; (2) Demonstrated R2R OLEDs can be as efficient as batch controls (Figure 1) (3) Developed & validated basic designs for key equipment necessary for R2R SM-OLEDs; (4) Developed know-hows & specifications on materials & ink formulations critical to wetcoating; (5) Developed key …
Date: July 31, 2012
Creator: Liu, Jie Jerry
Object Type: Report
System: The UNT Digital Library
The Effect of the Recovery Act on the River Corridor Closure Project: Lessons Learned (open access)

The Effect of the Recovery Act on the River Corridor Closure Project: Lessons Learned

This summary report provides a high-level lessons learned by WCH of the impact to its project performance. The context is limited to the WCH project alone.
Date: July 31, 2012
Creator: Mackay, S. M.
Object Type: Report
System: The UNT Digital Library
Organization of American States: Background and Issues for Congress (open access)

Organization of American States: Background and Issues for Congress

This report covers the background of the Organization of American States (OAS). It discusses the importance of U.S. participation in this organization in order to exert authority and shape outcomes in the Western Hemisphere.
Date: July 31, 2012
Creator: Meyer, Peter J.
Object Type: Report
System: The UNT Digital Library
Energy Saving Melting and Revert Reduction Technology (E-SMARRT): Development of Surface Engineered Coating Systems for Aluminum Pressure Die Casting Dies: Towards a 'Smart' Die Coating (open access)

Energy Saving Melting and Revert Reduction Technology (E-SMARRT): Development of Surface Engineered Coating Systems for Aluminum Pressure Die Casting Dies: Towards a 'Smart' Die Coating

The main objective of this research program was to design and develop an optimal coating system that extends die life by minimizing premature die failure. In high-pressure aluminum die-casting, the die, core pins and inserts must withstand severe processing conditions. Many of the dies and tools in the industry are being coated to improve wear-resistance and decrease down-time for maintenance. However, thermal fatigue in metal itself can still be a major problem, especially since it often leads to catastrophic failure (i.e. die breakage) as opposed to a wear-based failure (parts begin to go out of tolerance). Tooling costs remain the largest portion of production costs for many of these parts, so the ability prevent catastrophic failures would be transformative for the manufacturing industry.The technology offers energy savings through reduced energy use in the die casting process from several factors, including increased life of the tools and dies, reuse of the dies and die components, reduction/elimination of lubricants, and reduced machine down time, and reduction of Al solder sticking on the die. The use of the optimized die coating system will also reduce environmental wastes and scrap parts. Current (2012) annual energy saving estimates, based on initial dissemination to the casting …
Date: July 31, 2012
Creator: Moore, Dr. John J. & Dr. Jianliang Lin,
Object Type: Report
System: The UNT Digital Library
Nevada National Security Site 2011 Waste Management Monitoring Report, Area 3 and Area 5 Radioactive Waste Management Site (open access)

Nevada National Security Site 2011 Waste Management Monitoring Report, Area 3 and Area 5 Radioactive Waste Management Site

Environmental monitoring data are collected at and around the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) at the Nevada National Security Site (NNSS). These data are associated with radiation exposure, air, groundwater, meteorology, and vadose zone. This report summarizes the 2011 environmental data to provide an overall evaluation of RWMS performance and to support environmental compliance and performance assessment (PA) activities. Some of these data (e.g., radiation exposure, air, and groundwater) are presented in other reports. Direct radiation monitoring data indicate exposure levels at the RWMSs are within the range of background levels measured at the NNSS. Slightly elevated exposure levels outside the Area 3 RWMS are attributed to nearby historical aboveground nuclear weapons tests. Air monitoring data show tritium concentrations in water vapor and americium and plutonium concentrations in air particles are only slightly above detection limits and background levels. The measured levels of radionuclides in air particulates and moisture are below derived concentration guides for these radionuclides. During the last 2 weeks of March 2011, gamma spectroscopy results for air particles showed measurable activities of iodine-131 (131I), cesium-134 (134Cs), and cesium-137 (137Cs). These results are attributed to the release of fission products from the damaged …
Date: July 31, 2012
Creator: National Security Technologies, LLC
Object Type: Report
System: The UNT Digital Library
Roles of nanoclusters in shear banding and plastic deformation of bulk metallic glasses (open access)

Roles of nanoclusters in shear banding and plastic deformation of bulk metallic glasses

During the course of this research we published 33 papers in various physics/material journals. We select four representing papers in this report and their results are summarized as follows. I. To study shear banding process, it is pertinent to know the intrinsic shear strain rate within a propagating shear band. To this aim, we used nanoindentation technique to probe the mechanical response of a Au49Ag5.5Pd2.3Cu26.9Si16.3 bulk metallic glass in locality and found notable pop-in events associated with shear band emission. Using a free volume model and under the situation when temperature and stress/hardness are fixed result in an equation, which predicts that hardness serration caused by pop-in decreases exponentially with the strain rate. Our data are in good agreement with the prediction. The result also predicts that, when strain rate is higher than a critical strain rate of 1700 s^-1, there will be no hardness serration, thereby no pop-in. In other words, multiple shear bandings will take place and material will flow homogeneously. The critical strain rate of 1700 s^-1 can be treated as the intrinsic strain rate within a shear band. We subsequently carried out a simulation study and showed that, if the imposed strain rate was over , …
Date: July 31, 2012
Creator: Nieh, T.G.
Object Type: Report
System: The UNT Digital Library
China Naval Modernization: Implications for U.S. Navy Capabilities—Background and Issues for Congress (open access)

China Naval Modernization: Implications for U.S. Navy Capabilities—Background and Issues for Congress

This report covers potential oversight issues for Congress in regard to China's military modernization effort. The following topics are discussed: whether the U.S. Navy in coming years will be large enough to adequately counter improved Chinese maritime anti-access forces while also adequately performing other missions of interest to U.S. policymakers around the world; the Navy's ability to counter Chinese ASBMs and submarines; and whether the Navy, in response to China's maritime anti-access capabilities, should shift over time to a more distributed fleet architecture.
Date: July 31, 2012
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Coast Guard Cutter Procurement: Background and Issues for Congress (open access)

Coast Guard Cutter Procurement: Background and Issues for Congress

This report looks at the cost to fund the Coast Guard's program of record's (POR) call for procuring eight National Security Cutters (NSCs), 25 Offshore Patrol Cutters (OPCs), and 58 Fast Response Cutters (FRCs) as replacements for 90 aging Coast Guard cutters and patrol craft. It also addresses issues for maintenance, future acquisition, and definitions of the types of cutters.
Date: July 31, 2012
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Energy Saving Melting and Revert Reduction Technology (E-SMARRT): Melting Efficiency Improvement (open access)

Energy Saving Melting and Revert Reduction Technology (E-SMARRT): Melting Efficiency Improvement

Steel foundries melt recycled scrap in electric furnaces and typically consume 35-100% excess energy from the theoretical energy requirement required to pour metal castings. This excess melting energy is multiplied by yield losses during casting and finishing operations resulting in the embodied energy in a cast product typically being three to six times the theoretical energy requirement. The purpose of this research project was to study steel foundry melting operations to understand energy use and requirements for casting operations, define variations in energy consumption, determine technologies and practices that are successful in reducing melting energy and develop new melting techniques and tools to improve the energy efficiency of melting in steel foundry operations.
Date: July 31, 2012
Creator: Peaslee, Principal Investigator Kent & Co-PI’s: Von Richards, Jeffrey Smith
Object Type: Report
System: The UNT Digital Library