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1,604 Matching Results
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Hanford Site Environmental Surveillance Data Report for Calendar Year 2007
Environmental surveillance on and around the Hanford Site, located in southeastern Washington State, is conducted by the Pacific Northwest National Laboratory, which is operated by Battelle for the U.S. Department of Energy. The environmental surveillance data collected for this report provide a historical record of radionuclide and radiation levels attributable to natural causes, worldwide fallout, and Hanford Site operations. Data were also collected to monitor several chemicals and metals in Columbia River water, sediment, and wildlife. These data are included in this appendix. This report is the first of two appendices that support "Hanford Site Environmental Report for Calendar Year 2007" (PNNL-17603), which describes the Hanford Site mission and activities, general environmental features, radiological and chemical releases from operations, status of compliance with environmental regulations, status of programs to accomplish compliance, Hanford Site cleanup and remediation efforts, and environmental monitoring activities and results.
Date:
October 13, 2008
Creator:
Bisping, Lynn E.
Object Type:
Report
System:
The UNT Digital Library
Kahler Independence of the G2-MSSM
The G{sub 2}-MSSM is a model of particle physics coupled to moduli fields with interesting phenomenology both for colliders and astrophysical experiments. In this paper we consider a more general model--whose moduli Kahler potential is a completely arbitrary G{sub 2}-holonomy Kahler potential and whose matter Kahler potential is also more general. We prove that the vacuum structure and spectrum of BSM particles is largely unchanged in this much more general class of theories. In particular, gaugino masses are still suppressed relative to the gravitino mass and moduli masses. We also consider the effects of higher order corrections to the matter Kahler potential and find a connection between the nature of the LSP and flavor effects.
Date:
October 31, 2008
Creator:
Acharya, Bobby S. & Bobkov, Konstantin
Object Type:
Article
System:
The UNT Digital Library
Addendum to the Corrective Action Decision Document/Closure Report for Corrective Action Unit 406: Area 3 Building 03-74 & Building 03-58 Underground Discharge Points and Corrective Action Unit 429: Area 3 Building 03-55 & Area 9 Building 09-52 Underground Discharge Points, Tonopah Test Range, Nevada, Revision 0
This document constitutes an addendum to the March 2000, Corrective Action Decision Document / Closure Report for Corrective Action Unit 406: Area 3 Building 03-74 & 03-58 Underground Discharge Points and Corrective Action Unit 429: Area 3 Building 03-55 & Area 9 Building 09-52 Underground Discharge Points (TTR) as described in the document Recommendations and Justifications for Modifications for Use Restrictions Established under the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office Federal Facility Agreement and Consent Order (UR Modification document) dated February 2008. The UR Modification document was approved by NDEP on February 26, 2008. The approval of the UR Modification document constituted approval of each of the recommended UR modifications. In conformance with the UR Modification document, this addendum consists of: • This cover page that refers the reader to the UR Modification document for additional information • The cover and signature pages of the UR Modification document • The NDEP approval letter • The corresponding section of the UR Modification document This addendum provides the documentation justifying the cancellation of the UR for CAS 03-51-001-0355 – Photo Shop UDP, Drains in CAU 429. It should be noted that there are no changes to CAU …
Date:
October 1, 2008
Creator:
Kidman, Lynn
Object Type:
Report
System:
The UNT Digital Library
3D CFD Electrochemical and Heat Transfer Model of an Integrated-Planar Solid Oxide Electrolysis Cells
A three-dimensional computational fluid dynamics (CFD) electrochemical model has been created to model high-temperature electrolysis cell performance and steam electrolysis in a new novel integrated planar porous-tube supported solid oxide electrolysis cell (SOEC). The model is of several integrated planar cells attached to a ceramic support tube. This design is being evaluated with modeling at the Idaho National Laboratory. Mass, momentum, energy, and species conservation and transport are provided via the core features of the commercial CFD code FLUENT. A solid-oxide fuel cell (SOFC) model adds the electrochemical reactions and loss mechanisms and computation of the electric field throughout the cell. The FLUENT SOFC user-defined subroutine was modified for this work to allow for operation in the SOEC mode. Model results provide detailed profiles of temperature, Nernst potential, operating potential, activation over-potential, anode-side gas composition, cathode-side gas composition, current density and hydrogen production over a range of stack operating conditions. Mean per-cell area-specific-resistance (ASR) values decrease with increasing current density. Predicted mean outlet hydrogen and steam concentrations vary linearly with current density, as expected. Effects of variations in operating temperature, gas flow rate, cathode and anode exchange current density, and contact resistance from the base case are presented. Contour plots …
Date:
October 1, 2008
Creator:
Hawkes, Grant & O'Brien, James E.
Object Type:
Article
System:
The UNT Digital Library
Small-Scale Readout System Prototype for the STAR PIXEL Detector
Development and prototyping efforts directed towards construction of a new vertex detector for the STAR experiment at the RHIC accelerator at BNL are presented. This new detector will extend the physics range of STAR by allowing for precision measurements of yields and spectra of particles containing heavy quarks. The innermost central part of the new detector is a high resolution pixel-type detector (PIXEL). PIXEL requirements are discussed as well as a conceptual mechanical design, a sensor development path, and a detector readout architecture. Selected progress with sensor prototypes dedicated to the PIXEL detector is summarized and the approach chosen for the readout system architecture validated in tests of hardware prototypes is discussed.
Date:
October 10, 2008
Creator:
Szelezniak, Michal; Anderssen, Eric; Greiner, Leo; Matis, Howard; Ritter, Hans Georg; Stezelberger, Thorsten et al.
Object Type:
Article
System:
The UNT Digital Library
NSRL Extraction Bump Control in the Booster
Due to inadequacies in the user interface of the booster orbit control system, a number of new tools were developed. The first priority was an accurate calculation of the winding currents given specific displacements at each extraction septa. Next, the physical limits of the power supplies ({+-}600 amps) needed to be taken into account. In light of this limit, a system is developed that indicates to the user what the allowed values of one bump parameter are once the other two have been specified. Finally, techniques are developed to account for the orbit behavior once power supplies are requested to exceed their {+-}600 amp limit. This includes a recalculation of bump parameters and a calculation of the amplitude of the residuals. Following this, possible areas for further development are outlined. These techniques were computationally developed in Mathematica and tested in the Methodical Accelerator Design (MAD) program before they were implemented into the control system. At the end, a description of the implementation of these techniques in a new interface is described. This includes a depiction of the appearance and functionality of the graphical user interface, a description of the input and output flow, and an outline of how each important …
Date:
October 1, 2008
Creator:
Brennan,L.
Object Type:
Report
System:
The UNT Digital Library
Final Report - Chemical Industry Corrosion Management - A Comprehensive Information System (ASSET 2)
The research sponsored by this project has greatly expanded the ASSET corrosion prediction software system to produce a world-class technology to assess and predict engineering corrosion of metals and alloys corroding by exposure to hot gases. The effort included corrosion data compilation from numerous industrial sources and data generation at Shell Oak Ridge National Laboratory and several other companies for selected conditions. These data were organized into groupings representing various combinations of commercially available alloys and corrosion by various mechanisms after acceptance via a critical screening process to ensure the data were for alloys and conditions, which were adequately well defined, and of sufficient repeatability. ASSET is the largest and most capable, publicly-available technology in the field of corrosion assessment and prediction for alloys corroding by high temperature processes in chemical plants, hydrogen production, energy conversion processes, petroleum refining, power generation, fuels production and pulp/paper processes. The problems addressed by ASSET are: determination of the likely dominant corrosion mechanism based upon information available to the chemical engineers designing and/or operating various processes and prediction of engineering metal losses and lifetimes of commercial alloys used to build structural components. These assessments consider exposure conditions (metal temperatures, gas compositions and pressures), alloy …
Date:
October 10, 2008
Creator:
Randy C. John, Arthur L. Young, Arthur D. Pelton, William T. Thompson adn Ian G. Wright
Object Type:
Report
System:
The UNT Digital Library
Matrix solution to longitudinal impedance of multi-layer circular structures
A matrix method in which radial wave propagation is treated in analogy to longitudinal transmission lines is presented and applied to finding the longitudinal coupling impedance of axially symmetric multi-layer beam tubes. The method is demonstrated in the case of a Higher Order Mode ferrite absorber with an inserted coated ceramic beam tube. The screening of the ferrite damping properties by the dielectric beam tube is discussed.
Date:
October 1, 2008
Creator:
Hahn,H.
Object Type:
Report
System:
The UNT Digital Library
Impact on Spin Tune From Horizontal Orbital Angle Between Snakes and Orbital Angle Between Spin Rotators
To keep the spin tune in the spin depolarizing resonance free region is required for accelerating polarized protons to high energy. In RHIC, two snakes are located at the opposite side of each accelerator. They are configured to yield a spin tune of 1/2. Two pairs of spin rotators are located at either side of two detectors in each ring in RHIC to provide longitudinal polarization for the experiments. Since the spin rotation from vertical to longitudinal is localized between the two rotators, the spin rotators do not change the spin tune. However, due to the imperfection of the orbits around the snakes and rotators, the spin tune can be shifted. This note presents the impact of the horizontal orbital angle between the two snakes on the spin tune, as well as the effect of the vertical orbital angle between two rotators at either side of the collision point on the spin tune.
Date:
October 1, 2008
Creator:
Bai,M.; Ptitsyn, V. & Roser, T.
Object Type:
Report
System:
The UNT Digital Library
The Role of a Host Protein (TIP) in the Resistance Response of Arabidopsis to Turnip Crinkle Virus Infection.
Our research on Turnip crinkle virus (TCV) has shown that the viral capsid protein (CP) is both a virulence factor as well as the elicitor of a hypersensitive resistance response (HR) to the virus in Arabidopsis. Initially, we identified a protein from Arabidopsis that specifically interacted with the viral CP using a yeast two-hybrid screen. This protein, designated TIP for TCV-Interacting Protein, is a member of the NAC family of plant transcription factors implicated in the regulation of development and senescence. When TCV CP was mutated to eliminate its ability to interact with TIP, the corresponding virus mutants broke the HR-mediated resistance conferred by the HRT resistance (R) gene in Arabidopsis ecotype Dijon (Di)-17. This result suggested that TIP is a component of the signal transduction pathway that leads to the genetically specified TCV resistance. We next confirmed that TIP and the viral CP interact in plant cells and that this interaction prevents nuclear localization of this transcription factor. We demonstrated that TCV CP suppresses post-transcriptional gene silencing (PTGS), a newly discovered RNA-mediated defense system in plants. Together these results suggest that the CP is a virulence factor that could well be functioning through its interaction with TIP. We have …
Date:
October 20, 2008
Creator:
Morris, T. Jack
Object Type:
Report
System:
The UNT Digital Library
The universal criterion for switching a magnetic vortex core in soft magnetic nanodots
The universal criterion for ultrafast vortex core switching between core-up and -down vortex bi-states in soft magnetic nanodots was empirically investigated by micromagnetic simulations and combined with an analytical approach. Vortex-core switching occurs whenever the velocity of vortex core motion reaches a critical value, which is {nu}{sub c} = 330 {+-} 37 m/s for Permalloy, as estimated from numerical simulations. This critical velocity was found to be {nu}{sub c} = {eta}{sub c}{gamma} {radical}A{sub ex} with A{sub ex} the exchange stiffness, {gamma} the gyromagnetic ratio, and an estimated proportional constant {eta}{sub c} = 1.66 {+-} 0.18. This criterion does neither depend on driving force parameters nor on the dimension or geometry of the magnetic specimen. The phase diagrams for the vortex core switching criterion and its switching time with respect to both the strength and angular frequency of circular rotating magnetic fields were derived, which offer practical guidance for implementing vortex core switching into future solid state information storage devices.
Date:
October 1, 2008
Creator:
Lee, K. S.; Kim, S. K.; Yu, Y. S.; Choi, Y. S.; Guslienko, K. Y.; Jung, H. et al.
Object Type:
Article
System:
The UNT Digital Library
Production of Hydrogen for Clean and Renewable Source of Energy for Fuel Cell Vehicles
This was a two-year project that had two major components: 1) the demonstration of a PV-electrolysis system that has separate PV system and electrolysis unit and the hydrogen generated is to be used to power a fuel cell based vehicle; 2) the development of technologies for generation of hydrogen through photoelectrochemical process and bio-mass derived resources. Development under this project could lead to the achievement of DOE technical target related to PEC hydrogen production at low cost. The PEC part of the project is focused on the development of photoelectrochemical hydrogen generation devices and systems using thin-film silicon based solar cells. Two approaches are taken for the development of efficient and durable photoelectrochemical cells; 1) An immersion-type photoelectrochemical cells (Task 3) where the photoelectrode is immersed in electrolyte, and 2) A substrate-type photoelectrochemical cell (Task 2) where the photoelectrode is not in direct contact with electrolyte. Four tasks are being carried out: Task 1: Design and analysis of DC voltage regulation system for direct PV-to-electrolyzer power feed Task 2: Development of advanced materials for substrate-type PEC cells Task 3: Development of advanced materials for immersion-type PEC cells Task 4: Hydrogen production through conversion of biomass-derived wastes
Date:
October 31, 2008
Creator:
Deng, Xunming; Ingler, William B, Jr.; Abraham, Martin; Castellano, Felix; Coleman, Maria; Collins, Robert et al.
Object Type:
Report
System:
The UNT Digital Library
Chromosomal mosaicism in mouse two-cell embryos after paternal exposure to acrylamide
Chromosomal mosaicism in human preimplantation embryos is a common cause ofspontaneous abortions, however, our knowledge of its etiology is limited. We used multicolor fluorescence in situ hybridization (FISH) painting to investigate whether paternally-transmitted chromosomal aberrations result in mosaicism in mouse 2-cell embryos. Paternal exposure to acrylamide, an important industrial chemical also found in tobacco smoke and generated during the cooking process of starchy foods, produced significant increases in chromosomally defective 2-cell embryos, however, the effects were transient primarily affecting the postmeiotic stages of spermatogenesis. Comparisons with our previous study of zygotes demonstrated similar frequencies of chromosomally abnormal zygotes and 2-cell embryos suggesting that there was no apparent selection against numerical or structural chromosomal aberrations. However, the majority of affected 2-cell embryos were mosaics showing different chromosomal abnormalities in the two blastomeric metaphases. Analyses of chromosomal aberrations in zygotes and 2-cell embryos showed a tendency for loss of acentric fragments during the first mitotic division ofembryogenesis, while both dicentrics and translocations apparently underwent propersegregation. These results suggest that embryonic development can proceed up to the end of the second cell cycle of development in the presence of abnormal paternal chromosomes and that even dicentrics can persist through cell division. The high …
Date:
October 14, 2008
Creator:
Marchetti, Francesco; Bishop, Jack; Lowe, Xiu & Wyrobek, Andrew J
Object Type:
Article
System:
The UNT Digital Library
Final Report: Technical Support for Innovative Energy Systems the U.S. Chemical Industry -- Innovative Energy Systems Pilot Project - Chemicals Project Integrator
The University of Illinois at Chicago Energy Resources Center (UIC/ERC) was originally selected to carry out the role of project integrator for a planned solicitation calling for proposals for innovative concepts for energy efficient systems in the chemical industry. The selection was made as a result of a DOE Announcement of Funding Opportunity issued by the DOE Golden Field Office. The U.S. DOE, due to funding constraints, decided to change the role of project integrator into one of technical support to DOE and the Vision 2020 Steering Committee in carrying out the oversight and management of the projects selected from the planned innovative concepts solicitation. This project, initiated in April, 2005, was established to provide that technical support to the U.S. DOE Innovative Energy Systems Pilot Project for the US Chemical Industry. In the late summer of 2006, and as a continuation of the baseline technology analysis conducted by UIC/ERC under this project, DOE requested that UIC/ERC assist in the development of “technology briefs” in support of the DOE Save Energy Now program. The 100 technology briefs developed under this contract were utilized by the Energy Experts as part of their Energy Saving Assessments (ESA).
Date:
October 30, 2008
Creator:
Investigator, John Cuttica - Principal & Engineer, Dr Steffen Mueller - Lead
Object Type:
Report
System:
The UNT Digital Library
Peer review of the National Transportation Safety Board structural analysis of the I-35W bridge collapse.
The Engineering Sciences Center at Sandia National Laboratories provided an independent peer review of the structural analysis supporting the National Transportation Safety Board investigation of the August 1, 2007 collapse of the I-35W Bridge in Minneapolis. The purpose of the review was to provide an impartial critique of the analysis approach, assumptions, solution techniques, and conclusions. Subsequent to reviewing numerous supporting documents, a SNL team of staff and management visited NTSB to participate in analysis briefings, discussions with investigators, and examination of critical elements of the bridge wreckage. This report summarizes the opinion of the review team that the NTSB analysis effort was appropriate and provides compelling supporting evidence for the NTSB probable cause conclusion.
Date:
October 1, 2008
Creator:
Gwinn, Kenneth West; Redmond, James Michael & Wellman, Gerald William
Object Type:
Report
System:
The UNT Digital Library
Top Quark Pair Production Cross Section and Forward-Backward Asymmetry at the Tevatron
We present recent results on top quark pair production cross section and forward-backward asymmetry at the Tevatron. Three new cross section measurements from CDF and one new measurement from DO are presented that utilize the full dataset available. A new DO top cross section combination gives a ttbar production cross section of sigma ttbar = 7.83 + 0.46-0.45 (stat) + 0.64-0.53 (syst) +-0.48 (lumi). The new CDF cross section combination for ttbar production is found to be 7.0 +- 0.3 (stat) +- 0.4 (syst) +- 0.4 (lumi) pb giving a total uncertainty of 9%, very close to the that of the current best theoretical predictions. It is important to measure the top cross section in as many different channels as possible and investigate their compatibility. This is useful as new physics might show up differently in the different channels. Thus any significant discrepancy could be a sign of new physics. Three new measurements of the forward-backward asymmetry are also presented. The two CDF measurements unfold the observed asymmetry back to parton level in order to directly compare the values obtained with theoretical predictions. The DO measurement is not unfolded and therefore does not depend on the specific method used for …
Date:
October 1, 2008
Creator:
Lister, Alison
Object Type:
Article
System:
The UNT Digital Library
Air, Thermal and Water Management for PEM Fuel Cell Systems
Document discussing the management of different properties of the PEM fuel cells.
Date:
October 1, 2008
Creator:
Liu, Mark K. Gee Chung
Object Type:
Article
System:
The UNT Digital Library
Dislocation-Radiation Obstacle Interactions: Developing Improved Mechanical Property Constitutive Models
The objective of this program was to understand the interaction of dislocations with a wide range of obstacles commonly produced in materials under irradiation (dislocation loops, voids, helium bubbles, stacking fault tetrahedra and radiation-induced precipitates). The approach employed in this program combined multi-scale modeling and dynamic in-situ and static ex-situ transmission electron microscopy experiments.
Date:
October 10, 2008
Creator:
Robertson, Ian
Object Type:
Report
System:
The UNT Digital Library
Scaling Behavior of Barkhausen Avalanches along the Hysteresis loop in Nucleation-Mediated Magnetization Reversal Process
We report the scaling behavior of Barkhausen avalanches for every small field step along the hysteresis loop in CoCrPt alloy film having perpendicular magnetic anisotropy. Individual Barkhausen avalanche is directly observed utilizing a high-resolution soft X-ray microscopy that provides real space images with a spatial resolution of 15 nm. Barkhausen avalanches are found to exhibit power-law scaling behavior at all field steps along the hysteresis loop, despite their different patterns for each field step. Surprisingly, the scaling exponent of the power-law distribution of Barkhausen avalanches is abruptly altered from 1 {+-} 0.04 to 1.47 {+-} 0.03 as the field step is close to the coercive field. The contribution of coupling among adjacent domains to Barkhausen avalanche process affects the sudden change of the scaling behavior observed at the coercivity-field region on the hysteresis loop of CoCrPt alloy film.
Date:
October 14, 2008
Creator:
Im, Mi-Young; Fischer, Peter; Kim, D.-H. & Shin, S.-C.
Object Type:
Article
System:
The UNT Digital Library
Economic Benefits, Carbon Dioxide (CO2) Emissions Reductions, and Water Conservation Benefits from 1,000 Megawatts (MW) of New Wind Power in Nevada (Fact Sheet)
The U.S. Department of Energy?s Wind Powering America Program is committed to educating state-level policymakers and other stakeholders about the economic, CO2 emissions, and water conservation impacts of wind power. This analysis highlights the expected impacts of 1000 MW of wind power in Nevada. Although construction and operation of 1000 MW of wind power is a significant effort, six states have already reached the 1000-MW mark. We forecast the cumulative economic benefits from 1000 MW of development in Nevada to be $1.1 billion, annual CO2 reductions are estimated at 2.3 million tons, and annual water savings are 944 million gallons.
Date:
October 1, 2008
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Data validation and security for reprocessing.
Next generation nuclear fuel cycle facilities will face strict requirements on security and safeguards of nuclear material. These requirements can result in expensive facilities. The purpose of this project was to investigate how to incorporate safeguards and security into one plant monitoring system early in the design process to take better advantage of all plant process data, to improve confidence in the operation of the plant, and to optimize costs. An existing reprocessing plant materials accountancy model was examined for use in evaluating integration of safeguards (both domestic and international) and security. International safeguards require independent, secure, and authenticated measurements for materials accountability--it may be best to design stand-alone systems in addition to domestic safeguards instrumentation to minimize impact on operations. In some cases, joint-use equipment may be appropriate. Existing domestic materials accountancy instrumentation can be used in conjunction with other monitoring equipment for plant security as well as through the use of material assurance indicators, a new metric for material control that is under development. Future efforts will take the results of this work to demonstrate integration on the reprocessing plant model.
Date:
October 1, 2008
Creator:
Tolk, Keith Michael; Merkle, Peter Benedict; DurÔan, Felicia Angelica & Cipiti, Benjamin B.
Object Type:
Report
System:
The UNT Digital Library
Addendum to the Closure Report for Corrective Action Unit 271: Areas 25, 26, and 27 Septic Systems Nevada Test Site, Nevada, Revision 0
This document constitutes an addendum to the August 2004, Closure Report for Corrective Action Unit 271, Areas 25, 26, and 27 Septic Systems as described in the document Recommendations and Justifications for Modifications for Use Restrictions Established under the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office Federal Facility Agreement and Consent Order (UR Modification document) dated February 2008. The UR Modification document was approved by NDEP on February 26, 2008. The approval of the UR Modification document constituted approval of each of the recommended UR modifications. In conformance with the UR Modification document, this addendum consists of: • This cover page that refers the reader to the UR Modification document for additional information • The cover and signature pages of the UR Modification document • The NDEP approval letter • The corresponding section of the UR Modification document This addendum provides the documentation justifying the modification of the UR for CAS 27-05-02, Leachfield. This UR was established as part of a Federal Facility Agreement and Consent Order (FFACO) corrective action and is based on the presence of contaminants at concentrations greater than the action levels established at the time of the initial investigation (FFACO, 1996; as …
Date:
October 1, 2008
Creator:
Kidman, Lynn
Object Type:
Report
System:
The UNT Digital Library
Lucasfilm, Save Energy Now (SEN) Data Center Assessment Summary
This assessment summary describes how the industrial Technologies Program helped Lucasfilm to find ways to improve the efficiency of its data center by performing a Save Energy Now energy assessment.
Date:
October 1, 2008
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Predications and Observations of Global Beta-induced Alfven-acoustic Modes in JET and NSTX
In this paper we report on observations and interpretations of a new class of global MHD eigenmode solutions arising in gaps in the low frequency Alfven-acoustic continuum below the geodesic acoustic mode frequency. These modes have been just reported (Gorelenkov et al 2007 Phys. Lett. 370 70-7) where preliminary comparisons indicate qualitative agreement between theory and experiment. Here we show a more quantitative comparison emphasizing recent NSTX experiments on the observations of the global eigenmodes, referred to as beta-induced Alfven-acoustic eigenmodes (BAAEs), which exist near the extrema of the Alfven-acoustic continuum. In accordance to the linear dispersion relations, the frequency of these modes may shift as the safety factor, q, profile relaxes. We show that BAAEs can be responsible for observations in JET plasmas at relatively low beta <2% as well as in NSTX plasmas at relatively high beta >20%. In NSTX plasma observed magnetic activity has the same properties as predicted by theory for the mode structure and the frequency. Found numerically in NOVA simulations BAAEs are used to explain the observed properties of relatively low frequency experimental signals seen in NSTX and JET tokamaks.
Date:
October 21, 2008
Creator:
N.N. Gorelenkov, et. al.
Object Type:
Report
System:
The UNT Digital Library