Absolute calibration method for fast-streaked, fiber optic light collection, spectroscopy systems. (open access)

Absolute calibration method for fast-streaked, fiber optic light collection, spectroscopy systems.

This report outlines a convenient method to calibrate fast (<1ns resolution) streaked, fiber optic light collection, spectroscopy systems. Such a system is used to collect spectral data on plasmas generated in the A-K gap of electron beam diodes fielded on the RITS-6 accelerator (8-12MV, 140-200kA). On RITS, light is collected through a small diameter (200 micron) optical fiber and recorded on a fast streak camera at the output of 1 meter Czerny-Turner monochromator (F/7 optics). To calibrate such a system, it is necessary to efficiently couple light from a spectral lamp into a 200 micron diameter fiber, split it into its spectral components, with 10 Angstroms or less resolution, and record it on a streak camera with 1ns or less temporal resolution.
Date: April 1, 2010
Creator: Johnston, Mark D.; Frogget, Brent; Oliver, Bryan Velten; Maron, Yitzhak; Droemer, Darryl W. & Crain, Marlon D.
Object Type: Report
System: The UNT Digital Library
Accident source terms for pressurized water reactors with high-burnup cores calculated using MELCOR 1.8.5. (open access)

Accident source terms for pressurized water reactors with high-burnup cores calculated using MELCOR 1.8.5.

In this study, risk-significant pressurized-water reactor severe accident sequences are examined using MELCOR 1.8.5 to explore the range of fission product releases to the reactor containment building. Advances in the understanding of fission product release and transport behavior and severe accident progression are used to render best estimate analyses of selected accident sequences. Particular emphasis is placed on estimating the effects of high fuel burnup in contrast with low burnup on fission product releases to the containment. Supporting this emphasis, recent data available on fission product release from high-burnup (HBU) fuel from the French VERCOR project are used in this study. The results of these analyses are treated as samples from a population of accident sequences in order to employ approximate order statistics characterization of the results. These trends and tendencies are then compared to the NUREG-1465 alternative source term prescription used today for regulatory applications. In general, greater differences are observed between the state-of-the-art calculations for either HBU or low-burnup (LBU) fuel and the NUREG-1465 containment release fractions than exist between HBU and LBU release fractions. Current analyses suggest that retention of fission products within the vessel and the reactor coolant system (RCS) are greater than contemplated in the …
Date: April 1, 2010
Creator: Gauntt, Randall O.; Powers, Dana Auburn; Ashbaugh, Scott G.; Leonard, Mark Thomas & Longmire, Pamela
Object Type: Report
System: The UNT Digital Library
Applying Systems Engineering in a Renewable Energy Research and Development Environment: Preprint (open access)

Applying Systems Engineering in a Renewable Energy Research and Development Environment: Preprint

This paper examines lessons learned in systems engineering research and development at the National Renewable Energy Laboratory and explores new ideas for future process enhancements.
Date: April 1, 2010
Creator: Snyder, N. & Antkowiak, M.
Object Type: Article
System: The UNT Digital Library
Assessing the near-term risk of climate uncertainty : interdependencies among the U.S. states. (open access)

Assessing the near-term risk of climate uncertainty : interdependencies among the U.S. states.

Policy makers will most likely need to make decisions about climate policy before climate scientists have resolved all relevant uncertainties about the impacts of climate change. This study demonstrates a risk-assessment methodology for evaluating uncertain future climatic conditions. We estimate the impacts of climate change on U.S. state- and national-level economic activity from 2010 to 2050. To understand the implications of uncertainty on risk and to provide a near-term rationale for policy interventions to mitigate the course of climate change, we focus on precipitation, one of the most uncertain aspects of future climate change. We use results of the climate-model ensemble from the Intergovernmental Panel on Climate Change's (IPCC) Fourth Assessment Report 4 (AR4) as a proxy for representing climate uncertainty over the next 40 years, map the simulated weather from the climate models hydrologically to the county level to determine the physical consequences on economic activity at the state level, and perform a detailed 70-industry analysis of economic impacts among the interacting lower-48 states. We determine the industry-level contribution to the gross domestic product and employment impacts at the state level, as well as interstate population migration, effects on personal income, and consequences for the U.S. trade balance. We …
Date: April 1, 2010
Creator: Loose, Verne W.; Lowry, Thomas Stephen; Malczynski, Leonard A.; Tidwell, Vincent Carroll; Stamber, Kevin Louis; Reinert, Rhonda K. et al.
Object Type: Report
System: The UNT Digital Library
Assessment of severe accident source terms in pressurized-water reactors with a 40% mixed-oxide and 60% low-enriched uranium core using MELCOR 1.8.5. (open access)

Assessment of severe accident source terms in pressurized-water reactors with a 40% mixed-oxide and 60% low-enriched uranium core using MELCOR 1.8.5.

As part of a Nuclear Regulatory Commission (NRC) research program to evaluate the impact of using mixed-oxide (MOX) fuel in commercial nuclear power plants, a study was undertaken to evaluate the impact of the usage of MOX fuel on the consequences of postulated severe accidents. A series of 23 severe accident calculations was performed using MELCOR 1.8.5 for a four-loop Westinghouse reactor with an ice condenser containment. The calculations covered five basic accident classes that were identified as the risk- and consequence-dominant accident sequences in plant-specific probabilistic risk assessments for the McGuire and Catawba nuclear plants, including station blackouts and loss-of-coolant accidents of various sizes, with both early and late containment failures. Ultimately, the results of these MELCOR simulations will be used to provide a supplement to the NRC's alternative source term described in NUREG-1465. Source term magnitude and timing results are presented consistent with the NUREG-1465 format. For each of the severe accident release phases (coolant release, gap release, in-vessel release, ex-vessel release, and late in-vessel release), source term timing information (onset of release and duration) is presented. For all release phases except for the coolant release phase, magnitudes are presented for each of the NUREG-1465 radionuclide groups. MELCOR …
Date: April 1, 2010
Creator: Gauntt, Randall O.; Goldmann, Andrew S. (Texas A&M University, College Station, TX); Wagner, Kenneth C.; Powers, Dana Auburn; Ashbaugh, Scott G. & Longmire, Pamela
Object Type: Report
System: The UNT Digital Library
Assessment of simulation predictions of hydrocarbon pool fire tests. (open access)

Assessment of simulation predictions of hydrocarbon pool fire tests.

An uncertainty quantification (UQ) analysis is performed on the fuel regression rate model within SIERRA/Fuego by comparing to a series of hydrocarbon tests performed in the Thermal Test Complex. The fuels used for comparison for the fuel regression rate model include methanol, ethanol, JP8, and heptane. The recently implemented flamelet combustion model is also assessed with a limited comparison to data involving measurements of temperature and relative mole fractions within a 2-m diameter methanol pool fire. The comparison of the current fuel regression rate model to data without UQ indicates that the model over predicts the fuel regression rate by 65% for methanol, 63% for ethanol, 95% for JP8, and 15% for heptane. If a UQ analysis is performed incorporating a range of values for transmittance, reflectance, and heat flux at the surface the current model predicts fuel regression rates within 50% of measured values. An alternative model which uses specific heats at inlet and boiling temperatures respectively and does not approximate the sensible heat is also compared to data. The alternative model with UQ significantly improves the comparison to within 25% for all fuels except heptane. Even though the proposed alternative model provides better agreement to data, particularly for …
Date: April 1, 2010
Creator: Luketa-Hanlin, Anay Josephine
Object Type: Report
System: The UNT Digital Library
CMMAD Usability Case Study in Support of Countermine and Hazard Sensing (open access)

CMMAD Usability Case Study in Support of Countermine and Hazard Sensing

During field trials, operator usability data were collected in support of lane clearing missions and hazard sensing for two robot platforms with Robot Intelligence Kernel (RIK) software and sensor scanning payloads onboard. The tests featured autonomous and shared robot autonomy levels where tasking of the robot used a graphical interface featuring mine location and sensor readings. The goal of this work was to provide insights that could be used to further technology development. The efficacy of countermine systems in terms of mobility, search, path planning, detection, and localization were assessed. Findings from objective and subjective operator interaction measures are reviewed along with commentary from soldiers having taken part in the study who strongly endorse the system.
Date: April 1, 2010
Creator: Walker, Victor G. & Gertman, David I.
Object Type: Article
System: The UNT Digital Library
Comment on"Sensitivity of the active fracture model parameter to fracture network orientation and injection scenarios" by Basagaoglu et al. (2009) (open access)

Comment on"Sensitivity of the active fracture model parameter to fracture network orientation and injection scenarios" by Basagaoglu et al. (2009)

Basagaoglu et al. (2009) present a study on detailed unsaturated flow behavior in two-dimensional fracture networks using numerical experiments (simulations) based on the lattice-Boltzmann method. Their results are valuable for improving our understanding of unsaturated flow processes and evaluating the active fracture model (AFM) that was developed for capturing large-scale preferential flow in fractured rocks (Liu et al., 1998; 2003). As indicated in Basagaoglu et al. (2009), a previous study was conducted to evaluate the AFM with numerical experiments (Seol et al., 2003). However, the methodology used in that study and the corresponding conclusions are highly questioned for the following two reasons. First, the evaluation relies on a condition that simulated water flow processes in a fracture network are adequately represented with a continuum approach, because they draw their conclusions by comparing simulation results with those obtained from a dual-continuum model based on the AFM. No effort was made by Seol et al. (2003) to justify the validity of the continuum approach for their specific fracture network that includes a small number of fractures only. (The analyses of Basagaoglu et al. (2009) do not need the similar condition.) Second, Seol et al. (2003) use numerical dispersion to represent the matrix …
Date: April 1, 2010
Creator: Liu, H.H.
Object Type: Article
System: The UNT Digital Library
Compressive behavior of fine sand. (open access)

Compressive behavior of fine sand.

The compressive mechanical response of fine sand is experimentally investigated. The strain rate, initial density, stress state, and moisture level are systematically varied. A Kolsky bar was modified to obtain uniaxial and triaxial compressive response at high strain rates. A controlled loading pulse allows the specimen to acquire stress equilibrium and constant strain-rates. The results show that the compressive response of the fine sand is not sensitive to strain rate under the loading conditions in this study, but significantly dependent on the moisture content, initial density and lateral confinement. Partially saturated sand is more compliant than dry sand. Similar trends were reported in the quasi-static regime for experiments conducted at comparable specimen conditions. The sand becomes stiffer as initial density and/or confinement pressure increases. The sand particle size become smaller after hydrostatic pressure and further smaller after dynamic axial loading.
Date: April 1, 2010
Creator: Martin, Bradley E. (Air Force Research Laboratory, Eglin, FL); Kabir, Md. E. (Purdue University, West Lafayette, IN); Song, Bo & Chen, Wayne (Purdue University, West Lafayette, IN)
Object Type: Report
System: The UNT Digital Library

Computer-Aided Optimization of Macroscopic Design Factors for Lithium-Ion Cell Performance and Life

Electric-drive vehicles enabled by power- and energy-dense batteries promise to improve vehicle efficiency and help reduce society's dependence on fossil fuels. Next generation plug-in hybrid vehicles and battery electric vehicles may also enable vehicles to be powered by electricity generated from clean, renewable resources; however, to increase the commercial viability of such vehicles, the cost, performance and life of the vehicles batteries must be further improved. This work illustrates a virtual design process to optimize the performance and life of large-format lithium ion batteries. Beginning with material-level kinetic and transport properties, the performance and life of multiple large-format cell designs are evaluated, demonstrating the impact of macroscopic design parameters such as foil thickness, tab location, and cell size and shape under various cycling conditions. Challenges for computer-aided engineering of large-format battery cells, such as competing requirements and objectives, are discussed.
Date: April 1, 2010
Creator: Smith, K.; Kim, G. H. & Pesaran, A.
Object Type: Presentation
System: The UNT Digital Library
Conductivity Histories Measured in Shock-Dispersed-Fuel Explosion Clouds (open access)

Conductivity Histories Measured in Shock-Dispersed-Fuel Explosion Clouds

The notion of high ion and electron concentrations in the detonation of aluminized explosive mixtures has aroused some interest in electro-magnetic effects that the SDF charges might generate when detonated. Beside the scientific aspects at least two questions appear to be of practical interest: (1) Does the detonation of an SDF charge create electro-magnetic disturbances strong enough to affect the operation of electrical infrastructure in for example a tunnel system? (2) Does the detonation of an SDF charge in a tunnel system create an electromagnetic signature that relays information of the charge performance to the outside environment?
Date: April 1, 2010
Creator: Kuhl, A L
Object Type: Report
System: The UNT Digital Library
Corrective Action Decision Document/Closure Report for Corrective Action Unit 560: Septic Systems, Nevada Test Site, Nevada, Revision 0 (open access)

Corrective Action Decision Document/Closure Report for Corrective Action Unit 560: Septic Systems, Nevada Test Site, Nevada, Revision 0

Corrective Action Unit 560 comprises seven corrective action sites (CASs): •03-51-01, Leach Pit •06-04-02, Septic Tank •06-05-03, Leach Pit •06-05-04, Leach Bed •06-59-03, Building CP-400 Septic System •06-59-04, Office Trailer Complex Sewage Pond •06-59-05, Control Point Septic System The purpose of this CADD/CR is to provide justification and documentation supporting the recommendation for closure of CAU 560 with no further corrective action. To achieve this, corrective action investigation (CAI) activities were performed from October 7, 2008, through February 24, 2010, as set forth in the Corrective Action Investigation Plan for Corrective Action Unit 560: Septic Systems, Nevada Test Site, Nevada, and Record of Technical Change No. 1. The purpose of the CAI was to fulfill the following data needs as defined during the data quality objective (DQO) process: •Determine whether contaminants of concern (COCs) are present. •If COCs are present, determine their nature and extent. •Provide sufficient information and data to complete appropriate corrective actions. The CAU 560 dataset from the investigation results was evaluated based on the data quality indicator parameters. This evaluation demonstrated the quality and acceptability of the dataset for use in fulfilling the DQO data needs. Analytes detected during the CAI were evaluated against final action …
Date: April 1, 2010
Creator: Evenson, Grant
Object Type: Report
System: The UNT Digital Library
Corrective Action Investigation Plan for Corrective Action Unit 106: Areas 5, 11 Frenchman Flat Atmospheric Sites, Nevada Test Site, Nevada, Revision 0 (open access)

Corrective Action Investigation Plan for Corrective Action Unit 106: Areas 5, 11 Frenchman Flat Atmospheric Sites, Nevada Test Site, Nevada, Revision 0

Corrective Action Unit (CAU) 106 is located in Area 5 of the Nevada Test Site, which is approximately 65 miles northwest of Las Vegas, Nevada. Corrective Action Unit 106 comprises the five corrective action sites (CASs) listed below: •05-23-02, GMX Alpha Contaminated Area •05-23-05, Atmospheric Test Site - Able •05-45-01, Atmospheric Test Site - Hamilton •05-45-04, 306 GZ Rad Contaminated Area •05-45-05, 307 GZ Rad Contaminated Area These sites are being investigated because existing information on the nature and extent of potential contamination is insufficient to evaluate and recommend corrective action alternatives (CAAs). Additional information will be obtained by conducting a corrective action investigation before evaluating CAAs and selecting the appropriate corrective action for each CAS. The results of the field investigation will support a defensible evaluation of viable CAAs that will be presented in the Corrective Action Decision Document. The sites will be investigated based on the data quality objectives (DQOs) developed on January 19, 2010, by representatives of the Nevada Division of Environmental Protection and the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office. The DQO process was used to identify and define the type, amount, and quality of data needed to develop and …
Date: April 1, 2010
Creator: Matthews, Patrick
Object Type: Report
System: The UNT Digital Library
Cybersecurity through Real-Time Distributed Control Systems (open access)

Cybersecurity through Real-Time Distributed Control Systems

Critical infrastructure sites and facilities are becoming increasingly dependent on interconnected physical and cyber-based real-time distributed control systems (RTDCSs). A mounting cybersecurity threat results from the nature of these ubiquitous and sometimes unrestrained communications interconnections. Much work is under way in numerous organizations to characterize the cyber threat, determine means to minimize risk, and develop mitigation strategies to address potential consequences. While it seems natural that a simple application of cyber-protection methods derived from corporate business information technology (IT) domain would lead to an acceptable solution, the reality is that the characteristics of RTDCSs make many of those methods inadequate and unsatisfactory or even harmful. A solution lies in developing a defense-in-depth approach that ranges from protection at communications interconnect levels ultimately to the control system s functional characteristics that are designed to maintain control in the face of malicious intrusion. This paper summarizes the nature of RTDCSs from a cybersecurity perspec tive and discusses issues, vulnerabilities, candidate mitigation approaches, and metrics.
Date: April 1, 2010
Creator: Kisner, Roger A; Manges, Wayne W; MacIntyre, Lawrence Paul; Nutaro, James J; Munro Jr, John K; Ewing, Paul D et al.
Object Type: Report
System: The UNT Digital Library
Deep Well #4 Backup Power Systems Project Closeout Report (open access)

Deep Well #4 Backup Power Systems Project Closeout Report

The project scope was to install a diesel generated power source to deep well 4 in addition to the existing commercial power source. The diesel power source and its fuel supply system shall be seismically qualified to withstand a Performance Category 4 (PC-4) seismic event. This diesel power source will permit the deep well to operate during a loss of commercial power. System design will incorporate the ability to select and transfer power between the new diesel power source and commercial power sources for the the deep well motor and TRA-672 building loads.
Date: April 1, 2010
Creator: Westwood, Jeremy
Object Type: Report
System: The UNT Digital Library
Description of the Sandia National Laboratories science, technology & engineering metrics process. (open access)

Description of the Sandia National Laboratories science, technology & engineering metrics process.

There has been a concerted effort since 2007 to establish a dashboard of metrics for the Science, Technology, and Engineering (ST&E) work at Sandia National Laboratories. These metrics are to provide a self assessment mechanism for the ST&E Strategic Management Unit (SMU) to complement external expert review and advice and various internal self assessment processes. The data and analysis will help ST&E Managers plan, implement, and track strategies and work in order to support the critical success factors of nurturing core science and enabling laboratory missions. The purpose of this SAND report is to provide a guide for those who want to understand the ST&E SMU metrics process. This report provides an overview of why the ST&E SMU wants a dashboard of metrics, some background on metrics for ST&E programs from existing literature and past Sandia metrics efforts, a summary of work completed to date, specifics on the portfolio of metrics that have been chosen and the implementation process that has been followed, and plans for the coming year to improve the ST&E SMU metrics process.
Date: April 1, 2010
Creator: Jordan, Gretchen B.; Watkins, Randall D.; Trucano, Timothy Guy; Burns, Alan Richard & Oelschlaeger, Peter
Object Type: Report
System: The UNT Digital Library
Development of autonomous magnetometer rotorcraft for wide area assessment (open access)

Development of autonomous magnetometer rotorcraft for wide area assessment

Large areas across the United States are potentially contaminated with UXO, with some ranges encompassing tens to hundreds of thousands of acres. Technologies are needed which will allow for cost effective wide area scanning with 1) near 100 % coverage and 2) near 100 % detection of subsurface ordnance or features indicative of subsurface ordnance. The current approach to wide area assessment is a multi-level one, in which medium - altitude fixed wing optical imaging is used for an initial site assessment. This assessment is followed with low altitude manned helicopter based magnetometry. Subsequent to this wide area assessment targeted surface investigations are performed using either towed geophysical sensor arrays or man portable sensors. In order to be an effective tool for small UXO detection, the sensing altitude for magnetic site investigations needs to be on the order of 1 – 3 meters. These altitude requirements mean that manned helicopter surveys will generally only be feasible in large, open and relatively flat terrains. While such surveys are effective in mapping large areas relatively fast there are substantial mobilization/demobilization, staffing and equipment costs associated with these surveys (resulting in costs of approximately $100-$150/acre). In addition, due to the low altitude there …
Date: April 1, 2010
Creator: Versteeg, Roelof; Anderson, Matt; Beard, Les; Corban, Eric; Curley, Darryl; Gamey, Jeff et al.
Object Type: Report
System: The UNT Digital Library
EFFECT OF TEMPERATURE AND HUMIDITY ON FORMALDEHYDE EMISSIONS IN TEMPORARY HOUSING UNITS (open access)

EFFECT OF TEMPERATURE AND HUMIDITY ON FORMALDEHYDE EMISSIONS IN TEMPORARY HOUSING UNITS

The effect of temperature and humidity on formaldehyde emissions from samples collected from temporary housing units (THUs) was studied. The THUs were supplied by the U.S Federal Emergency Management Administration (FEMA) to families that lost their homes in Louisiana and Mississippi during the Hurricane Katrina and Rita disasters. Based on a previous study 1, 2, four of the composite wood surface materials that dominated contributions to indoor formaldehyde were selected to analyze the effects of temperature and humidity on the emission factors. Humidity equilibration experiments were carried out on two of the samples to determine how long the samples take to equilibrate with the surrounding environmental conditions. Small chamber experiments were then conducted to measure emission factors for the four surface materials at various temperature and humidity conditions. The samples were analyzed for formaldehyde via high performance liquid chromatography. The experiments showed that increases in temperature or humidity contributed to an increase in emission factors. A linear regression model was built using natural log of percentage relative humidity (RH) and inverse of temperature (in K) as predictor variables, and natural log of emission factors as the target variable. The coefficients of both inverse temperature and log relative humidity with log …
Date: April 1, 2010
Creator: Parthasarathy, Srinandini; Maddalena, Randy L.; Russell, Marion L. & Apte, Michael G.
Object Type: Article
System: The UNT Digital Library
Electromagnetic coupling between transmitters and electro-explosive devices located within an enclosure. (open access)

Electromagnetic coupling between transmitters and electro-explosive devices located within an enclosure.

This report documents calculations conducted to determine if 42 low-power transmitters located within a metallic enclosure can initiate electro-explosive devices (EED) located within the same enclosure. This analysis was performed for a generic EED no-fire power level of 250 mW. The calculations show that if the transmitters are incoherent, the power available is 32 mW - approximately one-eighth of the assumed level even with several worst-case assumptions in place.
Date: April 1, 2010
Creator: Warne, Larry Kevin; Jorgenson, Roy Eberhardt & Coats, Rebecca Sue
Object Type: Report
System: The UNT Digital Library
Electrospun Silicon Nanowires as Lithium Anodes (open access)

Electrospun Silicon Nanowires as Lithium Anodes

None
Date: April 1, 2010
Creator: Schulz, Doug; Hoey, Justin; Smith, Jeremiah; Wu, Xiangfa; Akhatov, Iskander; Pederson, Larry et al.
Object Type: Article
System: The UNT Digital Library
Energy Storage for Power Systems Applications: A Regional Assessment for the Northwest Power Pool (NWPP) (open access)

Energy Storage for Power Systems Applications: A Regional Assessment for the Northwest Power Pool (NWPP)

Wind production, which has expanded rapidly in recent years, could be an important element in the future efficient management of the electric power system; however, wind energy generation is uncontrollable and intermittent in nature. Thus, while wind power represents a significant opportunity to the Bonneville Power Administration (BPA), integrating high levels of wind resources into the power system will bring great challenges to generation scheduling and in the provision of ancillary services. This report addresses several key questions in the broader discussion on the integration of renewable energy resources in the Pacific Northwest power grid. More specifically, it addresses the following questions: a) how much total reserve or balancing requirements are necessary to accommodate the simulated expansion of intermittent renewable energy resources during the 2019 time horizon, and b) what are the most cost effective technological solutions for meeting load balancing requirements in the Northwest Power Pool (NWPP).
Date: April 1, 2010
Creator: Kintner-Meyer, Michael CW; Balducci, Patrick J.; Jin, Chunlian; Nguyen, Tony B.; Elizondo, Marcelo A.; Viswanathan, Vilayanur V. et al.
Object Type: Report
System: The UNT Digital Library
EPAct Fleets and Clean Cities Help Each Other Achieve Transportation Goals, Vehicle Technologies Program (VTP) (Fact Sheet) (open access)

EPAct Fleets and Clean Cities Help Each Other Achieve Transportation Goals, Vehicle Technologies Program (VTP) (Fact Sheet)

This fact sheet explains the relationship between EPAct fleets and the Clean Cities initiative.
Date: April 1, 2010
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Evaluation of Activity Concentration Values and Doses due to the Transport of Low Level Radioactive Material (open access)

Evaluation of Activity Concentration Values and Doses due to the Transport of Low Level Radioactive Material

The International Atomic Energy Agency (IAEA) initiated an international Coordinated Research Project (CRP) to evaluate the safety of transport of naturally occurring radioactive material (NORM). This report presents the United States contribution to that IAEA research program. The focus of this report is on the analysis of the potential doses resulting from the transport of low level radioactive material. Specific areas of research included: (1) an examination of the technical approach used in the derivation of exempt activity concentration values and a comparison of the doses associated with the transport of materials included or not included in the provisions of Paragraph 107(e) of the IAEA Safety Standards, Regulations for the Safe Transport of Radioactive Material, Safety Requirements No. TS-R-1; (2) determination of the doses resulting from different treatment of progeny for exempt values versus the A{sub 1}/A{sub 2} values; and (3) evaluation of the dose justifications for the provisions applicable to exempt materials and low specific activity materials (LSA-I). It was found that the 'previous or intended use' (PIU) provision in Paragraph 107(e) is not risk informed since doses to the most highly exposed persons (e.g., truck drivers) are comparable regardless of intended use of the transported material. The PIU …
Date: April 1, 2010
Creator: Rawl, Richard R; Scofield, Patricia A; Leggett, Richard Wayne & Eckerman, Keith F
Object Type: Report
System: The UNT Digital Library
An Evaluation of Atmospheric-pressure Plasma for the Cost-Effective Deposition of Antireflection Coatings (open access)

An Evaluation of Atmospheric-pressure Plasma for the Cost-Effective Deposition of Antireflection Coatings

Atmospheric-pressure plasma deposition (APPD) has previously been used to deposit various functional materials including polymeric surface modification layers, transparent conducting oxides, and photo catalytic materials. For many plasma polymerized coatings, reaction occurs via free radical mechanism where the high energy electrons from the plasma activate the olefinic carbon-carbon double bonds - a typical functional group in such precursors. The precursors for such systems are typically inexpensive and readily available and have been used in vacuum PECVD previously. The objectives are to investigate: (1) the effect of plasma power, gas composition and substrate temperature on the Si-based film properties using triethylsilane(TES) as the precursor; and (2) the chemical, mechanical, and optical properties of several experimental matrices based on Design of Experiment (DOE) principals. A simple APPD route has been utilized to deposit Si based films from an inexpensive precursor - Triethylsilane (TES). Preliminary results indicates formation of Si-C & Si-O and Si-O, Si-C & Si-N bonds with oxygen and nitrogen plasmas respectively. N{sub 2}-O{sub 2} plasma showed mixed trend; however oxygen remains a significant portion of all films, despite attempts to minimize exposure to atmosphere. SiN, SiC, and SiO ratios can be modified by the reaction conditions resulting in differing film …
Date: April 1, 2010
Creator: Sailer, Rob; Srinivasan, Guruvenket; Johnson, Kyle W. & Schulz, Douglas L.
Object Type: Article
System: The UNT Digital Library