Gun Control Legislation (open access)

Gun Control Legislation

This report discusses the salient and recurring gun control issues that have generated past congressional interest. It also discusses the development in the 112th Congress.
Date: May 2, 2012
Creator: Krouse, William J.
Object Type: Report
System: The UNT Digital Library
Kinetics of Colloidal Silica Gelation at EGS Conditions and Implications for Reservoir Modification (open access)

Kinetics of Colloidal Silica Gelation at EGS Conditions and Implications for Reservoir Modification

None
Date: May 2, 2012
Creator: Hunt, J. D.; Ezzedine, S. M.; Bourcier, W. & Roberts, S.
Object Type: Article
System: The UNT Digital Library
MACHINING ELIMINATION THROUGH APPLICATION OF THREAD FORMING FASTENERS IN NET SHAPED CAST HOLES (open access)

MACHINING ELIMINATION THROUGH APPLICATION OF THREAD FORMING FASTENERS IN NET SHAPED CAST HOLES

The ultimate objective of this work was to eliminate approximately 30% of the machining performed in typical automotive engine and transmission plants by using thread forming fasteners in as-cast holes of aluminum and magnesium cast components. The primary issues at the source of engineers’ reluctance to implementing thread forming fasteners in lightweight castings are: * Little proof of consistency of clamp load vs. input torque in either aluminum or magnesium castings. * No known data to understand the effect on consistency of clamp load as casting dies wear. The clamp load consistency concern is founded in the fact that a portion of the input torque used to create clamp load is also used to create threads. The torque used for thread forming may not be consistent due to variations in casting material, hole size and shape due to tooling wear and process variation (thermal and mechanical). There is little data available to understand the magnitude of this concern or to form the basis of potential solutions if the range of clamp load variation is very high (> +/- 30%). The range of variation that can be expected in as-cast hole size and shape over the full life cycle of a …
Date: May 2, 2012
Creator: Cleaver, Ryan J.; Cleaver, Todd H. & Talbott, Richard
Object Type: Report
System: The UNT Digital Library
METALLIC AND HYBRID NANOSTRUCTURES: FUNDAMENTALS AND APPLICATIONS (open access)

METALLIC AND HYBRID NANOSTRUCTURES: FUNDAMENTALS AND APPLICATIONS

This book chapter presents an overview of research conducted in our laboratory on preparation, optical and physico-chemical properties of metallic and nanohybrid materials. Metallic nanoparticles, particularly gold, silver, platinum or a combination of those are the main focus of this review manuscript. These metallic nanoparticles were further functionalized and used as templates for creation of complex and ordered nanomaterials with tailored and tunable structural, optical, catalytic and surface properties. Controlling the surface chemistry on/off metallic nanoparticles allows production of advanced nanoarchitectures. This includes coupled or encapsulated core-shell geometries, nano-peapods, solid or hollow, monometallic/bimetallic, hybrid nanoparticles. Rational assemblies of these nanostructures into one-, two- and tridimensional nano-architectures is described and analyzed. Their sensing, environmental and energy related applications are reviewed.
Date: May 2, 2012
Creator: Murph, S.
Object Type: Book
System: The UNT Digital Library
Neutron spectrometry - An essential tool for diagnosing implosions at the National Ignition Facility (open access)

Neutron spectrometry - An essential tool for diagnosing implosions at the National Ignition Facility

DT neutron yield (Y{sub n}), ion temperature (T{sub i}) and down-scatter ratio (dsr) determined from measured neutron spectra are essential metrics for diagnosing the performance of Inertial Confinement Fusion (ICF) implosions at the National Ignition Facility (NIF). A suite of neutron-Time-Of-Flight (nTOF) spectrometers and a Magnetic Recoil Spectrometer (MRS) have been implemented in different locations around the NIF target chamber, providing good implosion coverage and the redundancy required for reliable measurements of Yn, Ti and dsr. From the measured dsr value, an areal density ({rho}R) is determined from the relationship {rho}R{sub tot} (g/cm{sup 2}) = (20.4 {+-} 0.6) x dsr{sub 10-12 MeV}. The proportionality constant is determined considering implosion geometry, neutron attenuation and energy range used for the dsr measurement. To ensure high accuracy in the measurements, a series of commissioning experiments using exploding pushers have been used for in situ calibration. The spectrometers are now performing to the required accuracy, as indicated by the good agreement between the different measurements over several commissioning shots. In addition, recent data obtained with the MRS and nTOFs indicate that the implosion performance of cryogenically layered DT implosions, characterized by the experimental Ignition Threshold Factor (ITFx) which is a function of dsr (or …
Date: May 2, 2012
Creator: Mackinnon, A. J.; Johnson, M. G.; Frenje, J. A.; Casey, D. T.; Li, C. K.; Seguin, F. H. et al.
Object Type: Article
System: The UNT Digital Library
A novel particle Time Of Flight (pTOF) diagnostic for measurements of shock- and compression-bang times in D3He and DT implosions at the NIF (open access)

A novel particle Time Of Flight (pTOF) diagnostic for measurements of shock- and compression-bang times in D3He and DT implosions at the NIF

The particle-time-of-flight (pTOF) diagnostic, fielded alongside a Wedge Range-Filter (WRF) proton spectrometer, will provide an absolute timing for the shock-burn weighted {rho}R measurements that will validate the modeling of implosion dynamics at the National Ignition Facility (NIF). In the first phase of the project, pTOF has recorded accurate bang times in cryogenic DT, DT-Exploding Pusher and D{sup 3}He implosions using DD or DT neutrons with an accuracy better than {+-}70 ps. In the second phase of the project, a deflecting magnet will be incorporated into the pTOF design for simultaneous measurements of shock- and compression-bang times in D{sup 3}He-filled surrogate implosions using D{sup 3}He protons and DD-neutrons, respectively.
Date: May 2, 2012
Creator: Mackinnon, A.; Rinderknecht, H. G.; Johnson, M. G.; Zylstra, A. B.; Sinenian, N.; Rosenbergh, M. J. et al.
Object Type: Article
System: The UNT Digital Library
Renewable Energy and Environmental Sustainability Using Biomass From Dairy and Beef Animal Production: Final Report, Volume 1 (open access)

Renewable Energy and Environmental Sustainability Using Biomass From Dairy and Beef Animal Production: Final Report, Volume 1

The Texas Panhandle is regarded as the “Cattle Feeding Capital of the World”, producing 42% of the fed beef cattle in the United States within a 200-mile radius of Amarillo generating more than 5 million tons of feedlot manure /year. Apart from feedlots, the Bosque River Region in Erath County, just north of Waco, Texas with about 110,000 dairy cattle in over 250 dairies, produces 1.8 million tons of manure biomass (excreted plus bedding) per year. While the feedlot manure has been used extensively for irrigated and dry land crop production, most dairies, as well as other concentrated animal feeding operations (CAFO’s), the dairy farms utilize large lagoon areas to store wet animal biomass. Water runoff from these lagoons has been held responsible for the increased concentration of phosphorus and other contaminates in the Bosque River which drains into Lake Waco—the primary source of potable water for Waco’s 108,500 people. The concentrated animal feeding operations may lead to land, water, and air pollution if waste handling systems and storage and treatment structures are not properly managed. Manure-based biomass (MBB) has the potential to be a source of green energy at large coal-fired power plants and on smaller-scale combustion systems at …
Date: May 2, 2012
Creator: Annamalai, Kalyan; Sweeten, John M.; Auvermann, Brent W.; Mukhtar, Saqib; Caperada, Sergio; Engler, Cady R. et al.
Object Type: Report
System: The UNT Digital Library
SDU 6 MODELING STUDY TO SUPPORT DESIGN DEVELOPMENT (open access)

SDU 6 MODELING STUDY TO SUPPORT DESIGN DEVELOPMENT

In response to Technical Task Request (TTR) HLW-SSF-TTR-2012-0017 (1), SRNL performed modeling studies to evaluate alternative design features for the 32 million gallon Saltstone Disposal Unit (SDU) referred to as SDU 6. This initial modeling study was intended to assess the performance of major components of the structure that are most significant to the PA. Information provided by the modeling will support the development of a SDU 6 Preliminary Design Model and Recommendation Report to be written by SRR Closure and Waste Disposal Authority. Key inputs and assumptions for the modeling were provided to SRNL in SRR-SPT-2011-00113 (2). A table reiterates the base case and four sensitivity case studies requested in this reference. In general, as shown in Table 4, when compared to Vault 2 Case A, the Base Case SDU 6 design produced higher peak fluxes to the water table during the 10,000 year period of analysis but lower peak fluxes within a 15,000 to 20,000 time frame. SDU 6 will contain approximately ten times the inventory of a single Vault 2 and the SDU 6 footprint is comparable to that of a group of four Vault 2 disposal units. Therefore, the radionuclide flux from SDU 6 and that …
Date: May 2, 2012
Creator: Smith, F.
Object Type: Report
System: The UNT Digital Library
Simulation Tools for Modeling Thermal Spallation Drilling on Multiple Scales (open access)

Simulation Tools for Modeling Thermal Spallation Drilling on Multiple Scales

None
Date: May 2, 2012
Creator: Walsh, Stuart C.; Lomov, Ilya; Kanarska, Yuliya & Roberts, Jeffery J.
Object Type: Article
System: The UNT Digital Library
SSPC (Solid State Proton Conductors 15 Meeting (open access)

SSPC (Solid State Proton Conductors 15 Meeting

The field of solid state protonics has had a small but dedicated following for the past several decades. The collection of papers compiled in this special issue of Solid State Ionics were presented at the most recent international conference focused specifically on this topic, the 15th International Conference on Solid State Proton Conductors (SSPC-15) held in Santa Barbara, California, United States, August 15-20, 2010. Early recognition of the importance of proton transport in solids led to the establishment of the first meeting in this series in 1981, held in Paris in the form of a Danish-Frenchworkshop. The subsequent thirteen meetingswere all held inWestern Europe,with increasing participation from Asian, Eastern European and North and South American researchers. In recognition of the growing international interest in the field, SSPC-14 was held in Kyoto, Japan. SSPC-15, the first North American meeting in this series, built on the momentum of internationalization achieved in SSPC-14, ensuring that the best and brightest minds continue to contribute to the important problems still facing the understanding and manipulation of proton transport in solids. This occasion warrants an update to the SSPC history, and is given. Overall, the oxide proton conductors were the topic of greatest interest, reflecting the …
Date: May 2, 2012
Creator: Speakers; Yamaguchi, Shu; Rossman, George; Islam, M. Saiful; Gomez, Maria & Paddison, Stephen
Object Type: Report
System: The UNT Digital Library
Tactical Aircraft: F-22A Modernization Program Faces Cost, Technical, and Sustainment Risks (open access)

Tactical Aircraft: F-22A Modernization Program Faces Cost, Technical, and Sustainment Risks

A letter report issued by the Government Accountability Office with an abstract that begins "Total projected cost of the F-22A modernization program and related reliability and maintainability improvements more than doubled since the program started–from $5.4 billion to $11.7 billion–and the schedule for delivering full capabilities slipped 7 years, from 2010 to 2017. The content, scope, and phasing of planned capabilities also shifted over time with changes in requirements, priorities, and annual funding decisions. Visibility and oversight of the program’s cost and schedule is hampered by a management structure that does not track and account for the full cost of specific capability increments. Substantial infrastructure costs for labs, testing, management, and other activities directly support modernization but are not charged to its projects. The Air Force plans to manage its fourth modernization increment as a separate major acquisition program, as defined in DOD policy and statutory requirements."
Date: May 2, 2012
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library

Theoretical Predictions of the thermodynamic Properties of Solid Sorbents Capture CO2 Applications

We are establishing a theoretical procedure to identify most potential candidates of CO{sub 2} solid sorbents from a large solid material databank to meet the DOE programmatic goal for energy conversion; and to explore the optimal working conditions for the promising CO{sub 2} solid sorbents, especially from room to warm T ranges with optimal energy usage, used for both pre- and post-combustion capture technologies.
Date: May 2, 2012
Creator: Duan, Yuhua; Sorescu, Dan; David, Luebke & Pennline, Henry
Object Type: Presentation
System: The UNT Digital Library
Time-Resolved Soft X-Ray Spectra From Laser-Produced Cu Plasma (open access)

Time-Resolved Soft X-Ray Spectra From Laser-Produced Cu Plasma

The volumetric heating of a thin copper target has been studied with time resolved x-ray spectroscopy. The copper target was heated from a plasma produced using the Lawrence Livermore National Laboratory's Compact Multipulse Terrawatt (COMET) laser. A variable spaced grating spectrometer coupled to an x-ray streak camera measured soft x-ray emission (800-1550 eV) from the back of the copper target to characterize the bulk heating of the target. Radiation hydrodynamic simulations were modeled in 2-dimensions using the HYDRA code. The target conditions calculated by HYDRA were post-processed with the atomic kinetics code CRETIN to generate synthetic emission spectra. A comparison between the experimental and simulated spectra indicates the presence of specific ionization states of copper and the corresponding electron temperatures and ion densities throughout the laser-heated copper target.
Date: May 2, 2012
Creator: Cone, K. V.; Dunn, J.; Baldis, H. A.; May, M. J.; Purvis, M. A.; Scott, H. A. et al.
Object Type: Article
System: The UNT Digital Library
Ultra Fast X-ray Streak Camera for TIM Based Platforms (open access)

Ultra Fast X-ray Streak Camera for TIM Based Platforms

Ultra fast x-ray streak cameras are a staple for time resolved x-ray measurements. There is a need for a ten inch manipulator (TIM) based streak camera that can be fielded in a newer large scale laser facility. The LLNL ultra fast streak camera's drive electronics have been upgraded and redesigned to fit inside a TIM tube. The camera also has a new user interface that allows for remote control and data acquisition. The system has been outfitted with a new sensor package that gives the user more operational awareness and control.
Date: May 2, 2012
Creator: Marley, E; Shepherd, R; Fulkerson, E S; James, L; Emig, J & Norman, D
Object Type: Article
System: The UNT Digital Library
X-ray Streak Camera Cathode Development and Timing Accuracy of the 4w UV Fiducial System at the National Ignition Facility (open access)

X-ray Streak Camera Cathode Development and Timing Accuracy of the 4w UV Fiducial System at the National Ignition Facility

The convergent ablator experiments at the National Ignition Facility (NIF) are designed to measure the peak velocity and remaining ablator mass of an indirectly driven imploding capsule. Such a measurement can be performed using an x-ray source to backlight the capsule and an x-ray streak camera to record the capsule as it implodes. The ultimate goal of this experiment is to achieve an accuracy of 2% in the velocity measurement, which translates to a {+-}2 ps temporal accuracy over any 300 ps interval for the streak camera. In order to achieve this, a 4-{omega} (263nm) temporal fiducial system has been implemented for the x-ray streak camera at NIF. Aluminum, Titanium, Gold and Silver photocathode materials have been tested. Aluminum showed the highest quantum efficiency, with five times more peak signal counts per fiducial pulse when compared to Gold. The fiducial pulse data was analyzed to determine the centroiding a statistical accuracy for incident laser pulse energies of 1 and 10 nJ, showing an accuracy of {+-}1.6 ps and {+-}0.7 ps respectively.
Date: May 2, 2012
Creator: Opachich, Y P; Palmer, N; Homoelle, D; Hatch, B W; Bell, P; Bradley, D et al.
Object Type: Article
System: The UNT Digital Library
The 60-month all-sky BAT Survey of AGN and the Anisotropy of Nearby AGN (open access)

The 60-month all-sky BAT Survey of AGN and the Anisotropy of Nearby AGN

Surveys above 10 keV represent one of the the best resources to provide an unbiased census of the population of Active Galactic Nuclei (AGN). We present the results of 60 months of observation of the hard X-ray sky with Swift/BAT. In this timeframe, BAT detected (in the 15-55 keV band) 720 sources in an all-sky survey of which 428 are associated with AGN, most of which are nearby. Our sample has negligible incompleteness and statistics a factor of {approx}2 larger over similarly complete sets of AGN. Our sample contains (at least) 15 bona-fide Compton-thick AGN and 3 likely candidates. Compton-thick AGN represent a {approx}5% of AGN samples detected above 15 keV. We use the BAT dataset to refine the determination of the LogN-LogS of AGN which is extremely important, now that NuSTAR prepares for launch, towards assessing the AGN contribution to the cosmic X-ray background. We show that the LogN-LogS of AGN selected above 10 keV is now established to a {approx}10% precision. We derive the luminosity function of Compton-thick AGN and measure a space density of 7.9{sub -2.9}{sup +4.1} x 10{sup -5} Mpc{sup -3} for objects with a de-absorbed luminosity larger than 2 x 10{sup 42} erg s{sup -1}. …
Date: April 2, 2012
Creator: Ajello, M.; /KIPAC, Menlo Park; Alexander, D.M.; U., /Durham; Greiner, J.; /Garching, Max Planck Inst., MPE et al.
Object Type: Article
System: The UNT Digital Library
Adaptive Algebraic Multigrid for Finite Element Elliptic Equations with Random Coefficients (open access)

Adaptive Algebraic Multigrid for Finite Element Elliptic Equations with Random Coefficients

This thesis presents a two-grid algorithm based on Smoothed Aggregation Spectral Element Agglomeration Algebraic Multigrid (SA-{rho}AMGe) combined with adaptation. The aim is to build an efficient solver for the linear systems arising from discretization of second-order elliptic partial differential equations (PDEs) with stochastic coefficients. Examples include PDEs that model subsurface flow with random permeability field. During a Markov Chain Monte Carlo (MCMC) simulation process, that draws PDE coefficient samples from a certain distribution, the PDE coefficients change, hence the resulting linear systems to be solved change. At every such step the system (discretized PDE) needs to be solved and the computed solution used to evaluate some functional(s) of interest that then determine if the coefficient sample is acceptable or not. The MCMC process is hence computationally intensive and requires the solvers used to be efficient and fast. This fact that at every step of MCMC the resulting linear system changes, makes an already existing solver built for the old problem perhaps not as efficient for the problem corresponding to the new sampled coefficient. This motivates the main goal of our study, namely, to adapt an already existing solver to handle the problem (with changed coefficient) with the objective to achieve …
Date: April 2, 2012
Creator: Kalchev, D
Object Type: Report
System: The UNT Digital Library
Conservation Compliance and U.S. Farm Policy (open access)

Conservation Compliance and U.S. Farm Policy

The report discusses the Food Security Act of 1985 that included a number of significant conservation provisions designed to reduce production and conserve soil and water resources. It points out Conservation Compliance Today and Issues for the Next Farm Bill.
Date: April 2, 2012
Creator: Stubbs, Megan
Object Type: Report
System: The UNT Digital Library
Draft INFL Guideline on SIMS (open access)

Draft INFL Guideline on SIMS

Secondary Ion Mass Spectrometry (SIMS) is used for elemental and isotopic analysis of solid samples. The greatest strength of SIMS is the ability to analyze very small areas (as small as 50 nm using the CAMECA NanoSIMS, for example) and to generate high-spatial resolution maps of the distribution of elements and isotopes within the sample. The measurement of the isotopic composition of sample is usually straightforward, only requiring the analysis of the sample and that of an isotopic reference material for determination of the mass bias of the instrument. Quantification of elements, however, involves the analysis of matrix matched standards for the determination of the relative sensitivity factor (a function of both the element to be analyzed and the matrix). SIMS is commonly used in nuclear forensics for exploring the heterogeneity of the material on fine spatial scale.
Date: April 2, 2012
Creator: Kristo, M J
Object Type: Report
System: The UNT Digital Library
Effects of Radiation from Fukushima Dai-ichi on the U.S. Marine Environment (open access)

Effects of Radiation from Fukushima Dai-ichi on the U.S. Marine Environment

The massive Tohoku earthquake and tsunami of March 11, 2011, caused extensive damage in northeastern Japan, including damage to the Fukushima Dai-ichi nuclear power installation, which resulted in the release of radiation. Concerns arose about the potential effects of this released radiation on the U.S. marine environment and resources.
Date: April 2, 2012
Creator: Buck, Eugene H. & Upton, Harold F.
Object Type: Report
System: The UNT Digital Library
Eliminating the Renormalization Scale Ambiguity for Top-Pair Production Using the Principle of Maximum Conformality (open access)

Eliminating the Renormalization Scale Ambiguity for Top-Pair Production Using the Principle of Maximum Conformality

The uncertainty in setting the renormalization scale in finite-order perturbative QCD predictions using standard methods substantially reduces the precision of tests of the Standard Model in collider experiments. It is conventional to choose a typical momentum transfer of the process as the renormalization scale and take an arbitrary range to estimate the uncertainty in the QCD prediction. However, predictions using this procedure depend on the choice of renormalization scheme, leave a non-convergent renormalon perturbative series, and moreover, one obtains incorrect results when applied to QED processes. In contrast, if one fixes the renormalization scale using the Principle of Maximum Conformality (PMC), all non-conformal {l_brace}{beta}{sub i}{r_brace}-terms in the perturbative expansion series are summed into the running coupling, and one obtains a unique, scale-fixed, scheme-independent prediction at any finite order. The PMC renormalization scale {mu}{sub R}{sup PMC} and the resulting finite-order PMC prediction are both to high accuracy independent of choice of the initial renormalization scale {mu}{sub R}{sup init}, consistent with renormalization group invariance. Moreover, after PMC scale-setting, the n!-growth of the pQCD expansion is eliminated. Even the residual scale-dependence at fixed order due to unknown higher-order {l_brace}{beta}{sub i}{r_brace}-terms is substantially suppressed. As an application, we apply the PMC procedure to obtain …
Date: April 2, 2012
Creator: Brodsky, Stanley J. & Wu, Xing-Gang
Object Type: Article
System: The UNT Digital Library
Energy Conservation and Climate Change: Factors to Consider in the Design of the Nonbusiness Energy Property Credit (open access)

Energy Conservation and Climate Change: Factors to Consider in the Design of the Nonbusiness Energy Property Credit

A letter report issued by the Government Accountability Office with an abstract that begins "Under criteria for evaluating a tax credit design, both the performance-based and cost-based credits have advantages and disadvantages with neither design being unambiguously the better option based on current information. Both a cost-based and a performance-based credit are designed to reduce energy use and CO2 emissions by providing incentives for energy conservation investment. However, they differ in their relative effectiveness and costs. In general, a performance-based credit is more likely to effectively reduce energy use and CO2 emissions because it rewards energy savings from the investment rather than the cost-based credit’s rewarding of spending regardless of whether this spending results in energy savings. However, the performance-based credit may have significant up-front costs for energy audits, not required by the cost-based credit, which could reduce its effectiveness by discouraging investment. In addition, for taxpayers who do invest, these up-front costs may mean that a performance-based credit may have significantly higher taxpayer compliance and IRS administrative costs than a cost-based credit. A credit’s fairness depends on subjective judgments of how a credit varies with a taxpayer’s income level."
Date: April 2, 2012
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Fannie Mae's and Freddie Mac's Financial Problems (open access)

Fannie Mae's and Freddie Mac's Financial Problems

This report discusses the continuing conservatorship of Fannie Mae and Freddie Mac at a time of uncertainty in the housing, mortgage, and financial markets has raised doubts about the future of these enterprises, which are chartered by Congress as government-sponsored enterprises (GSEs) and whose debts are widely believed to be implicitly guaranteed by the federal government.
Date: April 2, 2012
Creator: Weiss, N. Eric
Object Type: Report
System: The UNT Digital Library
The Federal Government's Long-Term Fiscal Outlook: Spring 2012 Update (open access)

The Federal Government's Long-Term Fiscal Outlook: Spring 2012 Update

Other written product issued by the Government Accountability Office with an abstract that begins "Federal deficits and debt have reached historic highs in recent years. Congress has taken action to address the fiscal imbalance, but longer-term challenges remain. The Budget Control Act (BCA) of 2011 limits spending over the next decade and leads to an improved fiscal outlook. The act targets discretionary spending, and under both of GAO’s simulations, discretionary spending as a share of the economy would be lower in 2022 than at any point in the last 50 years. Further, as the economy recovers, revenue increases and spending decreases. While the BCA improved the outlook, it did not eliminate the longer-term challenge, in part because it did not focus on the fundamental drivers of the government’s future fiscal imbalances—a structural gap between revenues and spending driven by rising health care costs and demographics. As our 2011 simulations showed, if the Patient Protection and Affordable Care Act (PPACA) is implemented as intended it would have a major effect on the gap but would not eliminate it. The aging of the population and rising health care costs will continue putting upward pressure on spending. Assuming revenue in the long term …
Date: April 2, 2012
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library