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The Soils and Groundwater – EM-20 S&T Roadmap Quality Assurance Project Plan
The Soils and Groundwater – EM-20 Science and Technology Roadmap Project is a U.S. Department of Energy, Office of Environmental Management-funded initiative designed to develop new methods, strategies and technology for characterizing, modeling, remediating, and monitoring soils and groundwater contaminated with metals, radionuclides, and chlorinated organics. This Quality Assurance Project Plan provides the quality assurance requirements and processes that will be followed by EM-20 Roadmap Project staff.
Date:
February 11, 2008
Creator:
Fix, N. J.
Object Type:
Report
System:
The UNT Digital Library
POTENTIAL FOR HYDROGEN BUILDUP IN HANFORD SEALED AIR FILLED NUCLEAR STORAGE VESSELS
None
Date:
March 11, 2008
Creator:
BE, HEY
Object Type:
Report
System:
The UNT Digital Library
Demonstartion of density dependence of x-ray flux in a laser-driven hohlraum
Experiments have been conducted using laser-driven cylindrical hohlraums whose walls are machined from Ta{sub 2}O{sub 5} foams of 100 mg/cc and 4 g/cc densities. Measurements of the radiation temperature demonstrate that the lower density walls produce higher radiation temperatures than the high density walls. This is the first experimental demonstration of the prediction that this would occur [M. D. Rosen and J. H. Hammer, Phys. Rev. E 72, 056403 (2005)]. For high density walls, the radiation front propagates subsonically, and part of the absorbed energy is wasted by the flow kinetic energy. For the lower wall density, the front velocity is supersonic and can devote almost all of the absorbed energy to heating the wall.
Date:
February 11, 2008
Creator:
Young, P E; Rosen, M D; Hammer, J H; Hsing, W S; Glendinning, S G; Turner, R E et al.
Object Type:
Article
System:
The UNT Digital Library
Global paths of time-periodic solutions of the Benjamin-Ono equation connecting arbitrary traveling waves
We classify all bifurcations from traveling waves to non-trivial time-periodic solutions of the Benjamin-Ono equation that are predicted by linearization. We use a spectrally accurate numerical continuation method to study several paths of non-trivial solutions beyond the realm of linear theory. These paths are found to either re-connect with a different traveling wave or to blow up. In the latter case, as the bifurcation parameter approaches a critical value, the amplitude of the initial condition grows without bound and the period approaches zero. We propose a conjecture that gives the mapping from one bifurcation to its counterpart on the other side of the path of non-trivial solutions. By experimentation with data fitting, we identify the form of the exact solutions on the path connecting two traveling waves, which represents the Fourier coefficients of the solution as power sums of a finite number of particle positions whose elementary symmetric functions execute simple orbits in the complex plane (circles or epicycles). We then solve a system of algebraic equations to express the unknown constants in the new representation in terms of the mean, a spatial phase, a temporal phase, four integers (enumerating the bifurcation at each end of the path) and one …
Date:
December 11, 2008
Creator:
Ambrose, David M. & Wilkening, Jon
Object Type:
Article
System:
The UNT Digital Library
Hybrid MOSFET/Driver for Ultra-Fast Switching
The ultra-fast switching of power MOSFETs, in {approx}1ns, is very challenging. This is largely due to the parasitic inductance that is intrinsic to commercial packages used for both MOSFETs and drivers. Parasitic gate and source inductance not only limit the voltage rise time on the MOSFET internal gate structure but can also cause the gate voltage to oscillate. This paper describes a hybrid approach that substantially reduces the parasitic inductance between the driver and MOSFET gate as well as between the MOSFET source and its external connection. A flip chip assembly is used to directly attach the die-form power MOSFET and driver on a PCB. The parasitic inductances are significantly reduced by eliminating bond wires and minimizing lead length. The experimental results demonstrate ultra-fast switching of the power MOSFET with excellent control of the gate-source voltage.
Date:
July 11, 2008
Creator:
Tang, T. & Burkhart, C.
Object Type:
Article
System:
The UNT Digital Library
HYDROGEN EFFECTS ON STRAIN-INDUCED MARTENSITE FORMATION IN TYPE 304L STAINLESS STEEL
Unstable austenitic stainless steels undergo a strain-induced martensite transformation. The effect of hydrogen on this transformation is not well understood. Some researchers believe that hydrogen makes the transformation to martensite more difficult because hydrogen is an austenite stabilizer. Others believe that hydrogen has little or no effect at all on the transformation and claim that the transformation is simply a function of strain and temperature. Still other researchers believe that hydrogen should increase the ability of the metal to transform due to hydrogen-enhanced dislocation mobility and slip planarity. While the role of hydrogen on the martensite transformation is still debated, it has been experimentally verified that this transformation does occur in hydrogen-charged materials. What is the effect of strain-induced martensite on hydrogen embrittlement? Martensite near crack-tips or other highly strained regions could provide much higher hydrogen diffusivity and allow for quicker hydrogen concentration. Martensite may be more intrinsically brittle than austenite and has been shown to be severely embrittled by hydrogen. However, it does not appear to be a necessary condition for embrittlement since Type 21-6-9 stainless steel is more stable than Type 304L stainless steel but susceptible to hydrogen embrittlement. In this study, the effect of hydrogen on strain-induced …
Date:
December 11, 2008
Creator:
Morgan, M & Ps Lam, P
Object Type:
Article
System:
The UNT Digital Library
Effects of d-electrons in pseudopotential screened-exchange density functional calculations
We report a theoretical study on the role of shallow d states in the screened-exchange local density approximation (sX-LDA) band structure of binary semiconductor systems. We found that the inaccurate pseudo-wavefunctions can lead to (1) an overestimation of the screened-exchange interaction between the localized d states and the delocalized higher energy s and p states and (2) an underestimation of the screened-exchange interaction between the d states. The resulting sX-LDA band structures have substantially smaller band gaps compared with experiments. We correct the pseudo-wavefunctions of d states by including the semicore s and p states of the same shell in the valence states. The correction of pseudo-wavefunctions yields band gaps and the d state binding energy with good agreements with experiments and the full potential linearized augmented planewave (FLAPW) calculations. Compared with the quasi-particle GW method, our sX-LDA results shows not only similar quality on the band gaps but also much better d state binding energy. Combined with its capability of ground state structure calculation, the sX-LDA is expected to be a valuable theoretical tool for the II-VI and III-V (especially the III-N) bulk semiconductors and nanostructure studies.
Date:
August 11, 2008
Creator:
Wang, Lin-Wang; Lee, Byounghak; Canning, Andrew & Wang, Lin-Wang
Object Type:
Article
System:
The UNT Digital Library
Evidence for Direct CP Violation from Dalitz-plot analysis of B+ to K+pi+pi-
None
Date:
April 11, 2008
Creator:
Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type:
Article
System:
The UNT Digital Library
Transient Accident Analysis of the Glovebox System in a Large Process Room
Local transient hydrogen concentrations were evaluated inside a large process room when the hydrogen gas was released by three postulated accident scenarios associated with the process tank leakage and fire leading to a loss of gas confinement. The three cases considered in this work were fire in a room, loss of confinement from a process tank, and loss of confinement coupled with fire event. Based on these accident scenarios in a large and unventilated process room, the modeling calculations of the hydrogen migration were performed to estimate local transient concentrations of hydrogen due to the sudden leakage and release from a glovebox system associated with the process tank. The modeling domain represented the major features of the process room including the principal release or leakage source of gas storage system. The model was benchmarked against the literature results for key phenomena such as natural convection, turbulent behavior, gas mixing due to jet entrainment, and radiation cooling because these phenomena are closely related to the gas driving mechanisms within a large air space of the process room. The modeling results showed that at the corner of the process room, the gas concentrations migrated by the Case 2 and Case 3 scenarios …
Date:
January 11, 2008
Creator:
Lee, S.
Object Type:
Article
System:
The UNT Digital Library
KPiX, An Array of Self Triggered Charge Sensitive Cells Generating Digital Time and Amplitude Information
The Silicon Detector proposed for the International Linear Collider (ILC) requires electronic read-out that can be tightly coupled to the silicon detectors envisioned for the tracker and the electromagnetic calorimeter. The KPiX is a 1024-channel read-out chip that bump-bonds to the detector and communicates through a few digital signals, power, and detector bias. The KPiX front-end is a low-noise dual-range charge-amplifier with a dynamic range of 17 bit, achieved by autonomous switching of the feedback capacitor. The device takes advantage of the ILC duty cycle of 1 ms trains at 5 Hz rate by lowering the supply current after the data acquisition cycle for an average power consumption of <20 {micro}W/channel. During the 1 ms train, up to four events exceeding a programmable threshold can be stored, the amplitude as a voltage on a capacitor for subsequent digitization, the event time in digital format. The chip can be configured for other than ILC applications.
Date:
December 11, 2008
Creator:
Freytag, D.; Herbst, R.; /SLAC; Brau, J.; U., /Oregon; Breidenbach, M. et al.
Object Type:
Article
System:
The UNT Digital Library
Optical Technologies for Arming, Safing, Fuzing and Firing IV, SPIE, San Diego, CA 8/11/2008
The design and packaging of laser-optical system was tested to harsh environments outside lab conditions and post mortem activities will be discussed. Previously, custom mounts and bonded optical assemblies were environmentally tested to ensure their survivability. The results verified the sub-assemblies would enable the design of a laser-optical initiation system that could be fielded for use in extreme conditions. The design package, which utilized the proven opto-mechanical sub-assemblies, was then tested to the same levels as the sub-assemblies. The test regiment encompassed the harshest environments currently utilized. Temperature tests were performed ranging from a maximum of +75 degrees C to a minimum of -55 degrees C, allowing for two hour soak at each temperature set point. Vibration tests were performed to a maximum level of 15.5 grms for forty seconds in each of three critical axes. Shock tests were performed to a maximum impulse level of 5700 G’s for the sub-assemblies with a 1.1 millisecond long pulse; whereas the packaged laser system maximum level reached was 3700 G’s at 1.1 millisecond long pulse. The laser-optical assembly was visually inspected and functionally tested before and after each test to verify survival. As designed, the system covers were laser welded shut for …
Date:
August 11, 2008
Creator:
Bright, Michelle
Object Type:
Article
System:
The UNT Digital Library
CdMnTe in X-ray and Gamma-ray Detection: Potential Applications
CdMnTe can be a good candidate for gamma-ray detection because of its wide band-gap, high resistivity, and good electro-transport properties. Further, the ability to grow CMT crystals at relatively low temperatures ensures a high yield for manufacturing detectors with good compositional uniformity and few impurities. Our group at Brookhaven National Laboratory is investigating several CMT crystals, selecting a few of them to make detectors. In this paper, we discuss our initial characterization of these crystals and describe our preliminary results with a gamma-ray source.
Date:
August 11, 2008
Creator:
Cui, Y.; Bolotnikov, A.; Hossain, A.; Camarda, G.; Mycielski, A.; Yang, G. et al.
Object Type:
Article
System:
The UNT Digital Library
Experimental Research on the Laser Cyclotron Auto-Resonance Accelerator “LACARA”
The Laser Cyclotron Auto-Resonant Accelerator LACARA has successfully operated this year. Results are summarized, an interpretation of operating data is provided in the body of the report, and recommendations are made how the experiment should be carried forward. The Appendix A contains a description of the LACARA apparatus, currently installed at the Accelerator Test Facility, Brookhaven National Laboratory. This report summarizes the project, extending over three grant-years.
Date:
November 11, 2008
Creator:
Marshall, T C
Object Type:
Report
System:
The UNT Digital Library
INTERNATIONAL STUDIES OF ENHANCED WASTE LOADING AND IMPROVED MELT RATE FOR HIGH ALUMINA CONCENTRATION NUCLEAR WASTE GLASSES
The goal of this study was to determine the impacts of glass compositions with high aluminum concentrations on melter performance, crystallization and chemical durability for Savannah River Site (SRS) and Hanford waste streams. Glass compositions for Hanford targeted both high aluminum concentrations in waste sludge and a high waste loading in the glass. Compositions for SRS targeted Sludge Batch 5, the next sludge batch to be processed in the Defense Waste Processing Facility (DWPF), which also has a relatively high aluminum concentration. Three frits were selected for combination with the SRS waste to evaluate their impact on melt rate. The glasses were melted in two small-scale test melters at the V. G. Khlopin Radium Institute. The results showed varying degrees of spinel formation in each of the glasses. Some improvements in melt rate were made by tailoring the frit composition for the SRS feeds. All of the Hanford and SRS compositions had acceptable chemical durability.
Date:
September 11, 2008
Creator:
Fox, K; David Peeler, D & James Marra, J
Object Type:
Article
System:
The UNT Digital Library
Characterization of Vadose Zone Sediments Below the TX Tank Farm: Boreholes C3830, C3831, C3832 and RCRA Borehole 299-W10-27
This report was revised in September 2008 to remove acid-extractable sodium data from Tables 4.8, 4.28,4.43, and 4.59. The sodium data was removed due to potential contamination introduced during the acid extraction process. The rest of the text remains unchanged from the original report issued in April 2004. The overall goal of the Tank Farm Vadose Zone Project, led by CH2M HILL Hanford Group, Inc., is to define risks from past and future single-shell tank farm activities at Hanford. To meet this goal, CH2M HILL Hanford Group, Inc. tasked scientists from Pacific Northwest National Laboratory to perform detailed analyses on vadose zone sediments from within Waste Management Area (WMA) T-TX-TY. This report is the first of two reports written to present the results of these analyses. Specifically, this report contains all the geologic, geochemical, and selected physical characterization data collected on vadose zone sediment recovered from boreholes C3830, C3831, and C3832 in the TX Tank Farm, and from borehole 299-W-10-27 installed northeast of the TY Tank Farm.
Date:
September 11, 2008
Creator:
Serne, R. Jeffrey; Bjornstad, Bruce N.; Horton, Duane G.; Lanigan, David C.; Lindenmeier, Clark W.; Lindberg, Michael J. et al.
Object Type:
Report
System:
The UNT Digital Library
Search For the Lepton-Flavor Violating Decays Y(3S)->e tau and Y(3S)->mu tau
Charged lepton-flavor violating processes are extremely rare in the Standard Model, but they are predicted to occur in several beyond-the-Standard Model theories, including Supersymmetry or models with leptoquarks or compositeness. We present a search for such processes in a sample of 117 x 10{sup 6} {Upsilon}(3S) decays recorded with the BABAR detector. We place upper limits on the branching fractions BF({Upsilon}(3S) {yields} e{sup {+-}}{tau}{sup {-+}}) < 5.0 x 10{sup -6} and BF({Upsilon}(3S) {yields} {mu}{sup {+-}}{tau}{sup {-+}}) < 4.1 x 10{sup -6} at 90% confidence level. These results are used to place lower limits on the mass scale of beyond-the-Standard Model physics contributing to lepton-flavor violating decays of the {Upsilon}(3S).
Date:
December 11, 2008
Creator:
Aubert, B.
Object Type:
Article
System:
The UNT Digital Library
Information Dashboards
"A dashboard is a visual interface that provides at-a-glance views into key measures relevant to a particular objective or business process." Key Attributes: Graphical to focus attention on key trends, comparisons and exceptions, Display only relevant data, Inherently contain predefined conclusions. Note: Collecting user requirements is KEYfrom'Excel 2007 Dashboards& Reports for Dummies' by Michael Alexander
Date:
April 11, 2008
Creator:
Shutkin, Amy; Shutkin, Amy & Shutkin, Amy
Object Type:
Presentation
System:
The UNT Digital Library
Lepton Flavor Violation in tau and B decays at BaBar
This article summarizes the search for lepton flavor violating {tau} and B decays, using data collected by the BABAR detector at the PEP-II asymmetric-energy B factory.
Date:
July 11, 2008
Creator:
Manoni, Elisa & /Perugia U. /INFN, Perugia
Object Type:
Report
System:
The UNT Digital Library
Guidelines for beamline and front-end radiation shielding design at the Advanced Photon Source.
Shielding for the APS will be such that the individual radiation worker dose will be as low as reasonably achievable (ALARA). The ALARA goals for the APS are to keep the total of the work-related radiation exposure (exposure coming from other than natural or medical sources) as far below 500 person-mrem per year, collective total effective dose equivalent, as reasonably achievable. For an individual APS radiation worker, the goal is to keep the maximum occupational total effective dose equivalent of any one employee as far below 200 mrem/yr as reasonably achievable. The ALARA goal for APS beamline scientists is to keep the total of the work-related radiation exposure (exposure coming from other than natural or medical sources) as far below 100 person-mrem per year, collective total effective dose equivalent, as reasonably achievable. For an individual APS beamline scientist, the goal is to keep the maximum occupational total effective dose equivalent of any one scientist as far below 50 mrem/yr as reasonably achievable. The dose is actively monitored by the radiation monitors on the storage ring wall in each sector and by the frequent area surveys performed by the health physics personnel. For cases in which surveys indicate elevated hourly dose …
Date:
September 11, 2008
Creator:
Fernandez, P. & Division, X-Ray Science
Object Type:
Report
System:
The UNT Digital Library
FY07 LDRD Final Report Comparative Analysis of Genome Composition with Respect to Genotype-to-Phenotype Mapping and Metabolic Capability
None
Date:
February 11, 2008
Creator:
D'haeseleer, P
Object Type:
Report
System:
The UNT Digital Library
Characterization of Vadose Zone Sediment: Borehole 299-W23-19 [SX-115] in the S-SX Waste Management Area
This report was revised in September 2008 to remove acid-extractable sodium data from Tables 4.15 and 4.19. The sodium data was removed due to potential contamination introduced during the acid extraction process. The rest of the text remains unchanged from the original report issued in February 2002. The Tank Farm Vadose Zone Project is led by CH2M HILL Hanford Group, Inc. Their goals include defining risks from past and future single-shell tank farm activities, identifying and evaluating the efficacy of interim measures, and collecting geotechnical information and data. The purpose of these activities is to support future decisions made by the U.S. Department of Energy (DOE) regarding near-term operations, future waste retrieval, and final closure activities for the single-shell tank Waste Management Areas. To help in this effort, CH2M HILL Hanford Group, Inc. contracted with scientists at Pacific Northwest National Laboratory to analyze sediment samples collected from borehole 299-W23-19.
Date:
September 11, 2008
Creator:
Serne, R. Jeffrey; Bjornstad, Bruce N.; Lanigan, David C.; Gee, Glendon W.; Lindenmeier, Clark W.; Clayton, Ray E. et al.
Object Type:
Report
System:
The UNT Digital Library
SAVANNAH RIVER NATIONAL LABORATORYREGENERATIVE FUEL CELL PROJECT
A team comprised of governmental, academic and industrial partners led by the Savannah River National Laboratory developed and demonstrated a regenerative fuel cell system for backup power applications. Recent market assessments have identified emergency response and telecommunication applications as promising near-term markets for fuel cell backup power systems. The Regenerative Fuel Cell System (RFC) consisted of a 2 kg-per-day electrolyzer, metal-hydride based hydrogen storage units and a 5 kW fuel cell. Coupling these components together created a system that can produce and store its own energy from the power grid much like a rechargeable battery. A series of test were conducted to evaluate the performance of the RFC system under both steady-state and transit conditions that might be encountered in typical backup power applications. In almost all cases the RFC functioned effectively. Test results from the demonstration project will be used to support recommendations for future fuel cell and hydrogen component and system designs and support potential commercialization activities. In addition to the work presented in this report, further testing of the RFC system at the Center for Hydrogen Research in Aiken County, SC is planned including evaluating the system as a renewable system coupled with a 20kW-peak solar photovoltaic …
Date:
November 11, 2008
Creator:
Motyka, T
Object Type:
Report
System:
The UNT Digital Library
Light-Front Dynamics and AdS/QCD Correspondence: Gravitational FormFactors of Composite Hadrons
None
Date:
April 11, 2008
Creator:
Brodsky, Stanley J. & de Teramond, Guy F.
Object Type:
Article
System:
The UNT Digital Library
Characterization of Vadose Zone Sediment: RCRA Borehole 299-E33-338 Located Near the B-BX-BY Waste Management Area
This report was revised in September 2008 to remove acid-extractable sodium data from Table 4.8. The sodium data was removed due to potential contamination introduced during the acid extraction process. The rest of the text remains unchanged from the original report issued in June 2003. The overall goals of the of the Tank Farm Vadose Zone Project, led by CH2M HILL Hanford Group, Inc., are: 1) to define risks from past and future single-shell tank farm activities, 2) to identify and evaluate the efficacy of interim measures, and 3) to aid via collection of geotechnical information and data, future decisions that must be made by the U.S. Department of Energy (DOE) regarding the near-term operations, future waste retrieval, and final closure activities for the single-shell tank waste management areas. For a more complete discussion of the goals of the Tank Farm Vadose Zone Project, see the overall work plan, Phase 1 RCRA Facility Investigation/Corrective Measures Study Work Plan for the Single-Shell Tank Waste Management Areas (DOE 1999). Specific details on the rationale for activities performed at the B-BX-BY tank farm waste management area are found in CH2M HILL (2000).
Date:
September 11, 2008
Creator:
Lindenmeier, Clark W.; Serne, R. Jeffrey; Bjornstad, Bruce N.; Gee, Glendon W.; Schaef, Herbert T.; Lanigan, David C. et al.
Object Type:
Report
System:
The UNT Digital Library