Characterization of Uranium Solids Precipitated with Aluminosilicates (open access)

Characterization of Uranium Solids Precipitated with Aluminosilicates

At the Savannah River Site (SRS), the High-Level Waste (HLW) Tank Farms store and process high-level liquid radioactive wastes from the Canyons and recycle water from the Defense Waste Processing Facility. The waste is concentrated using evaporators to minimize the volume of space required for HLW storage. Recently, the 2H Evaporator was shutdown due to the crystallization of sodium aluminosilicate (NAS) solids (such as cancrinite and sodalite) that contained close to 10 weight percent of elementally-enriched uranium (U). Prior to extensive cleaning,the evaporator deposits resided on the evaporator walls and other exposed internal surfaces within the evaporator pot. Our goal is to support the basis for the continued safe operation of SRS evaporators and to gain more information that could be used to help mitigate U accumulation during evaporator operation.
Date: April 29, 2004
Creator: Duff, M. C.
Object Type: Article
System: The UNT Digital Library
The Coalition Provisional Authority (CPA): Origin, Characteristics, and Institutional Authorities (open access)

The Coalition Provisional Authority (CPA): Origin, Characteristics, and Institutional Authorities

The Coalition Provisional Authority (CPA or “the authority”) was established approximately one month after United States and coalition forces took control of Baghdad in Iraq on April 9, 2003.1 The authority’s mission was “to restore conditions of security and stability, to create conditions in which the Iraqi people can freely determine their own political future, (including by advancing efforts to restore and establish national and local institutions for representative governance) and facilitating economic recovery, sustainable reconstruction and development. This report discusses two views on how the authority was established, reviews selected characteristics of the authority, identifies statutory reporting requirements concerning the authority and the reconstruction of Iraq, and explores several policy issues.
Date: April 29, 2004
Creator: Halchin, L. Elaine
Object Type: Report
System: The UNT Digital Library
Economic Development Options and Constraints in Remote Rural Counties: A Case Study of the Great Plains Region (open access)

Economic Development Options and Constraints in Remote Rural Counties: A Case Study of the Great Plains Region

This report discusses socioeconomic characteristics and trends of 242 remote rural counties in seven states of the Great Plains region stretching from Texas to the Dakotas. Appendices provide individual county level data on socioeconomic trends in population, education, employment, and income for the 242 remote counties.
Date: April 29, 2004
Creator: Cowan, Tadlock
Object Type: Report
System: The UNT Digital Library
Effect of Growth Interruption on Surface Recombination Velocity in GaInAsSb/AlGaAsSb Heterostructures Grown by Organometallic Vapor Phase Epitaxy (open access)

Effect of Growth Interruption on Surface Recombination Velocity in GaInAsSb/AlGaAsSb Heterostructures Grown by Organometallic Vapor Phase Epitaxy

The effects of growth interruption on the quality of GaInAsSb/AlGaAsSb heterostructures grown by organometallic vapor phase epitaxy are reported. In-situ reflectance monitoring and ex-situ characterization by high-resolution x-ray diffraction, 4K photoluminescence (PL), and time-resolved PL indicate that GaInAsSb is extremely sensitive to growth interruption time as well as the ambient atmosphere during interruption. By optimizing the interruption sequence, surface recombination velocity as low as 20 cm/s was achieved for GaInAsSb/AlGaAsSb double heterostructures.
Date: April 29, 2004
Creator: Wang, C. A.; Shiau, D. A.; Donetsky, D.; Anikeev, S.; Belenky, G. & Luryi, S.
Object Type: Report
System: The UNT Digital Library
Experimental and Theoretical Studies of Nucleation in Supercooled Liquid Silicon. Final Program Report (open access)

Experimental and Theoretical Studies of Nucleation in Supercooled Liquid Silicon. Final Program Report

The original objectives of the present program consisted of two specific nucleation-related research activities; (1) to provide a set of experimental data that will enable the quantitative examination of classical nucleation theory, and (2) to describe the phenomenon of nucleation by developing general expressions of nucleation that include both the thermal and athermal components and that correctly consider and incorporate the transient effects that arise from the nonstationary cluster distribution profile.
Date: April 29, 2004
Creator: Im, J.
Object Type: Report
System: The UNT Digital Library
Flavor violation in warped extra dimensions and CP Asymmetries in B decays (open access)

Flavor violation in warped extra dimensions and CP Asymmetries in B decays

We show that CP asymmetries in b {yields} s hadronic decays are potentially affected by the presence of massive color-octet particles strongly coupled to the third generation quarks. Theories with warped extra dimensions provide natural candidates in the Kaluza-Klein excitations of gluons in scenarios where flavor-breaking by bulk fermion masses results in the localization of fermion wave-functions. Topcolor models, in which a new gauge interaction leads to top-condensation and a large top mass, also result in the presence of these color-octet states with TeV masses. We find that large effects are possible in modes such as B {yields} {phi}K{sub s}, B {yields} {eta}{prime}K{sub s} and B {yields} {pi}{sup 0}K{sub s} among others.
Date: April 29, 2004
Creator: Burdman, Gustavo
Object Type: Article
System: The UNT Digital Library
Gas Turbine Reheat Using In-Situ Combustion (open access)

Gas Turbine Reheat Using In-Situ Combustion

Siemens Westinghouse Power Corporation (SWPC) is developing in-situ reheat (fuel injection via airfoil injection) as a means for increasing cycle efficiency and power output, with possibly reduced emissions. This report discusses engineering cycle evaluations on various reheat approaches, using GateCycle and ChemCad software simulations of typical F-class and G-class engines, modified for alternative reheat cycles. The conclusion that vane 1 reheat offers the most advantageous design agrees with the conclusions of the detailed chemical kinetics (Task 2) as verified by high temperature testing (Task 3) and Blade path CFD (Task 1) tasks. The second choice design option (vane 2 reheat after vane 1 reheat) is also validated in all tasks. A conceptual design and next recommended development tasks are presented.
Date: April 29, 2004
Creator: Newby, R. A.; Bachovchin, D. M. & Lippert, T. E.
Object Type: Report
System: The UNT Digital Library
Grain Refinement of Permanent Mold Cast Copper Base Alloys (open access)

Grain Refinement of Permanent Mold Cast Copper Base Alloys

Grain refinement behavior of copper alloys cast in permanent molds was investigated. This is one of the least studied subjects in copper alloy castings. Grain refinement is not widely practiced for leaded copper alloys cast in sand molds. Aluminum bronzes and high strength yellow brasses, cast in sand and permanent molds, were usually fine grained due to the presence of more than 2% iron. Grain refinement of the most common permanent mold casting alloys, leaded yellow brass and its lead-free replacement EnviroBrass III, is not universally accepted due to the perceived problem of hard spots in finished castings and for the same reason these alloys contain very low amounts of iron. The yellow brasses and Cu-Si alloys are gaining popularity in North America due to their low lead content and amenability for permanent mold casting. These alloys are prone to hot tearing in permanent mold casting. Grain refinement is one of the solutions for reducing this problem. However, to use this technique it is necessary to understand the mechanism of grain refinement and other issues involved in the process. The following issues were studied during this three year project funded by the US Department of Energy and the copper casting …
Date: April 29, 2004
Creator: Sadayappan, M.; Thomson, J. P.; Elboujdaini, M.; Ping Gu, G. & Sahoo, M.
Object Type: Report
System: The UNT Digital Library
Heat Treatment Procedure Qualification for Steel Castings (open access)

Heat Treatment Procedure Qualification for Steel Castings

Heat treatment practices used by steel foundries have been carefully studied as part of comprehensive heat treatment procedure qualification development trials. These studies highlight the relationships between critical heat treatment process control parameters and heat treatment success. Foundry heat treatment trials to develop heat treatment procedure qualifications have shed light on the relationship between heat treatment theory and current practices. Furnace load time-temperature profiles in steel foundries exhibit significant differences depending on heat treatment equipment, furnace loading practice, and furnace maintenance. Time-temperature profiles of furnace control thermocouples can be very different from the time-temperature profiles observed at the center of casting loads in the furnace. Typical austenitization temperatures and holding times used by steel foundries far exceed what is required for transformation to austenite. Quenching and hardenability concepts were also investigated. Heat treatment procedure qualification (HTPQ) schema to demonstrate heat treatment success and to pre-qualify other alloys and section sizes requiring lesser hardenability have been developed. Tempering success is dependent on both tempering time and temperature. As such, furnace temperature uniformity and control of furnace loading during tempering is critical to obtain the desired mechanical properties. The ramp-up time in the furnace prior to the establishment of steady state heat …
Date: April 29, 2004
Creator: Charles, Mariol; Deskevich, Nicholas; Varkey, Vipin; Voigt, Robert & Wollenburg, Angela
Object Type: Report
System: The UNT Digital Library
High Resolution Transmission Grating Spectrometer for Edge Toroidal Rotation Measurements of Tokamak Plasmas (open access)

High Resolution Transmission Grating Spectrometer for Edge Toroidal Rotation Measurements of Tokamak Plasmas

We present a high throughput (f/3) visible (3500 - 7000 Angstrom) Doppler spectrometer for toroidal rotation velocity measurements of the Alcator C-Mod tokamak plasma. The spectrometer has a temporal response of 1 ms and a rotation velocity sensitivity of {approx}10{sup 5} cm/s. This diagnostic will have a tangential view and map out the plasma rotation at several locations along the outer half of the minor radius (r/a > 0.5). The plasma rotation will be determined from the Doppler shifted wavelengths of D{sub alpha} and magnetic and electric dipole transitions of highly ionized impurities in the plasma. The fast time resolution and high spectral resolving power are possible due to a 6' diameter circular transmission grating that is capable of {lambda}/{Delta}{lambda} {approx} 15500 at 5769 Angstrom in conjunction with a 50 {micro}m slit.
Date: April 29, 2004
Creator: Graf, A.; May, M.; Beiersdorfer, P.; Magee, E.; Lawrence, M.; Terry, J. et al.
Object Type: Article
System: The UNT Digital Library
Improved Scheme for Modeling Mass Transfer between Fracture and Matrix Continua with Particle Tracking Method (open access)

Improved Scheme for Modeling Mass Transfer between Fracture and Matrix Continua with Particle Tracking Method

The dual-continuum random-walk particle tracking approach is an attractive simulation method for simulating transport in a fractured porous medium. In order to be truly successful for such a model, however, the key issue is to properly simulate the mass transfer between the fracture and matrix continua. In a recent paper, Pan and Bodvarsson (2002) proposed an improved scheme for simulating fracture-matrix mass transfer, by introducing the concept of activity range into the calculation of fracture-matrix particle-transfer probability. By comparing with analytical solutions, they showed that their scheme successfully captured the transient diffusion depth into the matrix without any additional subgrid (matrix) cells. This technical note presents an expansion of their scheme to cases in which significant water flow through the fracture-matrix interface exists. The dual-continuum particle tracker with this new scheme was found to be as accurate as a numerical model using a more detailed grid. The improved scheme can be readily incorporated into the existing particle-tracking code, while still maintaining the advantage of needing no additional matrix cells to capture transient features of particle penetration into the matrix.
Date: April 29, 2004
Creator: Pan, L.; Seol, Y. & Bodvarsson, G.
Object Type: Report
System: The UNT Digital Library
Independent Counsel: Breakdown of Expenditures for David M. Barrett (open access)

Independent Counsel: Breakdown of Expenditures for David M. Barrett

Correspondence issued by the General Accounting Office with an abstract that begins "In a letter dated April 15, 2004, the Ranking Minority Member, House Committee on Government Reform, requested a monthly breakdown of all expenditures from October 2002 through September 2003 by Independent Counsel David M. Barrett. Under 28 U.S.C 596(c)(1) and (2) (2000), independent counsels are required to report on their expenditures from the permanent, indefinite appropriation established to fund independent counsel activities semiannually. We are required to audit these expenditures and report our findings to appropriate congressional committees. The request letter cited our two most recent semiannual reports, which covered the period in question on independent counsel expenditures."
Date: April 29, 2004
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Older Americans Act Nutrition Program (open access)

Older Americans Act Nutrition Program

This report discusses the elderly nutrition program of the Older Americans Act which provides grants to state agencies on aging to support congregate and home-delivered meals to persons 60 years and older. Funding and statistics of assistance are also addressed.
Date: April 29, 2004
Creator: O'Shaughnessy, Carol
Object Type: Report
System: The UNT Digital Library
Optical Coatings for Thermophotovoltaic Spectral Control (open access)

Optical Coatings for Thermophotovoltaic Spectral Control

The efficiency of thermophotovoltaic (TPV) energy conversion is dependent on efficient spectral control. An edge pass filter (short pass) in series with a highly doped, epitaxially grown layer has achieved the highest performance of TPV spectral control. Front surface, tandem filters have achieved the highest spectral efficiency and represent the best prospect for even higher spectral efficiency for TPV energy conversion systems. Specifically, improvements in the physical vapor deposition process, identification of other materials with a high index of refraction and a low absorption coefficient, and more efficient edge filter designs could provide higher TPV spectral performance.
Date: April 29, 2004
Creator: Fourspring, P. M.; DePoy, D. M.; Rahmlow, T. D., Jr.; Lazo-Wasem, J. E. & Gratrix, E. J.
Object Type: Report
System: The UNT Digital Library
ParaDiS on BlueGene/L: scalable line dynamics (open access)

ParaDiS on BlueGene/L: scalable line dynamics

We describe an innovative highly parallel application program, ParaDiS, which computes the plastic strength of materials by tracing the evolution of dislocation lines over time. We discuss the issues of scaling the code to tens of thousands of processors, and present early scaling results of the code run on a prototype of the BlueGene/L supercomputer being developed by IBM in partnership with the US DOE's ASC program.
Date: April 29, 2004
Creator: Bulatov, V.; Cai, W.; Fier, J.; Hiratani, M.; Pierce, T.; Tang, M. et al.
Object Type: Article
System: The UNT Digital Library
Potential-well distortion in barrier Rf (open access)

Potential-well distortion in barrier Rf

Head-tail asymmetry has been observed in the longitudinal beam profiles in the Fermilab Recycler Ring where protons or antiprotons are stored in rf barrier buckets. The asymmetry is caused by the distortion of the rf potential well in the presence of resistive impedance. Gaussian energy distribution can fit the observed asymmetric beam profile but not without discrepancy. It can also fit the measured energy distribution. On the other hand, generalized elliptic distribution gives a better fit to the beam profile. However, it fails to reproduce the observed energy distribution.
Date: April 29, 2004
Creator: Ng, King
Object Type: Article
System: The UNT Digital Library
Reserve Forces: Observations on Recent National Guard Use in Overseas and Homeland Missions and Future Challenges (open access)

Reserve Forces: Observations on Recent National Guard Use in Overseas and Homeland Missions and Future Challenges

Testimony issued by the General Accounting Office with an abstract that begins "As a result of the September 11, 2001, terrorist attacks and launch of the Global War on Terrorism, the National Guard has experienced the largest activation of its forces since World War II. The Guard consists of 350,000 Army Guard soldiers and 107,000 Air Guard members. With its unique dual status, it performs state missions under the governor and federal missions at home and overseas under the President. Since September 11, the Guard's missions have expanded, raising concerns about its ability to simultaneously perform all of these functions. The Department of Defense (DOD) funds the Army Guard for partial readiness to accomplish mission requirements assuming that there will be time to supply additional personnel and equipment in an extended conflict. In contrast, the Air Guard is funded to be an operational reserve ready on short notice. Today's testimony addresses GAO's observations on (1) the extent and purpose of the National Guard's use since September 11, (2) the effects of that use on Guard forces' readiness for future missions, and (3) the challenges that DOD, the states, and Congress face in organizing and equipping the Guard to support both …
Date: April 29, 2004
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Science and Technology Review June 2004 (open access)

Science and Technology Review June 2004

This months issue has the following articles: (1) ''A New Era in Plutonium Research''--Commentary by William H. Goldstein. (2) ''Shocking Plutonium to Reveal Its Secrets''--Livermore scientists are using a new gas gun located at the Nevada Test Site for shocking plutonium to extreme pressures and temperatures. (3) ''Strategic Supercomputing Comes of Age''--As supercomputing settles into the terascale regime, simulations reveal pertinent insights about the physics of stockpile stewardship. (4) ''Seeing the Universe in a Grain of Dust''--Livermore scientists refine analysis techniques for studying the first dust particles collected from a comet. (5) ''A Bang-Up Job: Keeping Things Clean at the Contained Firing Facility''--A new cleanup program at Livermore's Contained Firing Facility keeps the environment clean and beryllium exposure to a minimum.
Date: April 29, 2004
Creator: Henson, V E
Object Type: Report
System: The UNT Digital Library
Studies of laser-driven radiative blast waves (open access)

Studies of laser-driven radiative blast waves

We have performed two sets of experiments looking at laser-driven radiating blast waves. In one set of experiments the effect of a drive laser's passage through a background gas on the hydrodynamical evolution of blast waves was examined. It was found that the laser's passage heats a channel in the gas, creating a region where a portion of the blast wave front had an increased velocity, leading to the formation of a bump-like protrusion on the blast wave. The second set of experiments involved the use of regularly spaced wire arrays to induce perturbations on a blast wave surface. The decay of these perturbations as a function of time was measured for various wave number perturbations and found to be in good agreement with theoretical predictions.
Date: April 29, 2004
Creator: Edwards, M J; Hansen, J; Edens, A; Ditmire, T; Adams, R; Rambo, P et al.
Object Type: Article
System: The UNT Digital Library
U.S. International Broadcasting: Challenges Facing the Broadcasting Board of Governors (open access)

U.S. International Broadcasting: Challenges Facing the Broadcasting Board of Governors

Testimony issued by the General Accounting Office with an abstract that begins "The terrorist attacks of September 11, 2001, were a dramatic reminder of the importance of cultivating a better understanding of the United States and its policies with overseas audiences. U.S. public diplomacy activities include the efforts of the Broadcasting Board of Governors, which oversees all nonmilitary U.S. international broadcasting by the Voice of America (VOA) and several other broadcast entities. Such broadcasting helps promote a better understanding of the United States and serves U.S. interests by providing overseas audiences with accurate and objective news about the United States and the world. GAO has issued three reports over the past 4 years examining the organizational, marketing, resource, and performance reporting challenges faced by the Board. Our recommendations to the Board have included the need to address the long-standing issue of overlapping language services (i.e., where two services broadcast in the same language to the same audience) and to strengthen the Board's strategic planning and performance by placing a greater emphasis on results. The Board has taken significant steps to respond to these and other recommendations."
Date: April 29, 2004
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Beyond the standard model in many directions (open access)

Beyond the standard model in many directions

These four lectures constitute a gentle introduction to what may lie beyond the standard model of quarks and leptons interacting through SU(3){sub c} {direct_product} SU(2){sub L} {direct_product} U(1){sub Y} gauge bosons, prepared for an audience of graduate students in experimental particle physics. In the first lecture, I introduce a novel graphical representation of the particles and interactions, the double simplex, to elicit questions that motivate our interest in physics beyond the standard model, without recourse to equations and formalism. Lecture 2 is devoted to a short review of the current status of the standard model, especially the electroweak theory, which serves as the point of departure for our explorations. The third lecture is concerned with unified theories of the strong, weak, and electromagnetic interactions. In the fourth lecture, I survey some attempts to extend and complete the electroweak theory, emphasizing some of the promise and challenges of supersymmetry. A short concluding section looks forward.
Date: April 28, 2004
Creator: Quigg, Chris
Object Type: Article
System: The UNT Digital Library
A COMPUTATIONAL WORKBENCH ENVIRONMENT FOR VIRTUAL POWER PLANT SIMULATION (open access)

A COMPUTATIONAL WORKBENCH ENVIRONMENT FOR VIRTUAL POWER PLANT SIMULATION

This is the fourteenth Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-00NT41047. The goal of the project is to develop and demonstrate a Virtual Engineering-based framework for simulating the performance of Advanced Power Systems. Within the last quarter, good progress has been made on all aspects of the project. Software development efforts have focused primarily on completing a prototype detachable user interface for the framework and on integrating Carnegie Mellon Universities IECM model core with the computational engine. In addition to this work, progress has been made on several other development and modeling tasks for the program. These include: (1) improvements to the infrastructure code of the computational engine, (2) enhancements to the model interfacing specifications, (3) additional development to increase the robustness of all framework components, (4) enhanced coupling of the computational and visualization engine components, (5) a series of detailed simulations studying the effects of gasifier inlet conditions on the heat flux to the gasifier injector, and (6) detailed plans for implementing models for mercury capture for both warm and cold gas cleanup have been created.
Date: April 28, 2004
Creator: Bockelie, Mike; Swensen, Dave; Denison, Martin; Chen, Zumao; Linjewile, Temi; Maguire, Mike et al.
Object Type: Report
System: The UNT Digital Library
Corrective Action Decision Document for Corrective Action Unit 516: Septic Systems and Discharge Points, Nevada Test Site, Nevada: Revision 1 (open access)

Corrective Action Decision Document for Corrective Action Unit 516: Septic Systems and Discharge Points, Nevada Test Site, Nevada: Revision 1

This Corrective Action Decision Document (CADD) identifies and rationalizes the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office's selection of a recommended corrective action alternative appropriate to facilitate the closure of Corrective Action Unit (CAU) 516: Septic Systems and Discharge Points, Nevada Test Site (NTS), Nevada, under the Federal Facility Agreement and Consent Order. Located in Areas 3, 6, and 22 on the NTS, CAU 516 includes six Corrective Action Sites (CASs) consisting of two septic systems, a sump and piping, a clean-out box and piping, dry wells, and a vehicle decontamination area. Corrective action investigation activities were performed from July 22 through August 14, 2003, with supplemental sampling conducted in late 2003 and early 2004. The potential exposure pathways for any contaminants of concern (COCs) identified during the development of the DQOs at CAU 516 gave rise to the following objectives: (1) prevent or mitigate exposure to media containing COCs at concentrations exceeding PALs as defined in the corrective action investigation plan; and (2) prevent the spread of COCs beyond each CAS. The following alternatives have been developed for consideration at CAU 516: Alternative 1 - No Further Action; Alternative 2 - Clean Closure; and Alternative …
Date: April 28, 2004
Creator: United States. National Nuclear Security Administration. Nevada Site Office.
Object Type: Report
System: The UNT Digital Library
Development of a Standard Methodology for the Quantitative Measurement of Steel Phase Transformation Kinetics and Dilation Strains Using Dilatometric Methods, QMST (TRP 0015) (open access)

Development of a Standard Methodology for the Quantitative Measurement of Steel Phase Transformation Kinetics and Dilation Strains Using Dilatometric Methods, QMST (TRP 0015)

The purpose of this collaborative project was to develop a standard practice for obtaining and archiving quantitative steel transformation kinetic data and thermal strain data. Two families of dilatometric equipment were employed to develop this standard practice for testing bar product steels. These include high-speed quenching and deformation dilatometers and Gleeble{reg_sign} thermomechanical simulation instruments. Standard measurement, data interpretation and data reporting methods were developed and defined by the cross-industry QMST Consortium members consisting of steel-manufacturers, forgers, heat-treaters, modelers, automotive and heavy vehicle OEMs along with team expert technologists from the National Labs and academia. The team designed phase transformation experiments on two selected steel grades to validate the standard practices--a medium carbon grade SAE 1050 and an alloy steel SAE 8620. A final standard practice document was developed based on the two dilatometry methods, and was submitted to and approved by ASTM (available as A1033-04). The standard practice specifies a method for measuring austenite transformation under no elastic stress or plastic deformation. These methods will be an enabler for the development and electronic archiving of a quantitative database for process modeling using computer simulation software, and will greatly assist endusers in developing accurate process and product simulations during the thermo-mechanical …
Date: April 28, 2004
Creator: Metha, Manish & Oakwood, Tom
Object Type: Report
System: The UNT Digital Library