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NON-DESTRUCTIVE ASSAY OF CE-144 IN PRESENCE OF TRANSURANIC WASTE

NON-DESTRUCTIVE ASSAY OF CE-144 IN PRESENCE OF TRANSURANIC WASTE

Date: January 1, 2001
Creator: Laboratory, Los Alamos National
Description: The Ce- 144 isotope has been identified as a radionuclide produced in certain Los Alamos National Laboratory plutonium waste streams and thus may need to be quantified when present in reportable quantities for shipment to the Waste Isolation Pilot Plant (WIPP). The most intense gamma ray from Ce-144 was found to be the 133.53 keV peak. At this energy, there were no interfering plutonium or plutonium daughter gainma rays. Furthermore, it was determined that there were no interferences produced by Ce- 144 or its progenies that could degrade the plutonium isotopic analysis. At 5% of the total activity per gram of plutonium, the reportable limit, the Ce-144 peak at 133.53 keV will remain above the primary plutonium peak (129.3 keV) for approximately 7 years and remain quantifiable for at least 12 to 13 years from the time the isotope was chemically separated. It is therefore concluded that Ce-144 will be quantifiable whenever it exceeds 5% of the total activity per gram of plutonium, and will not interfere with the non-destructive assay of plutonium isotopic compositions.
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Steering magnet design for a limited space

Steering magnet design for a limited space

Date: May 4, 2009
Creator: Okamura,M.; Fite, J.; Lodestro, V.; Raparia, D. & Ritter, J.
Description: We compare two extreme designs of steering magnets. The first one is a very thin steering magnet design which occupies only 6 mm in length and can be additionally installed as needed. The other is realized by applying extra coil windings to a quadrupole magnet and does not consume any length. The properties and the features of these steering magnets are discussed.
Contributing Partner: UNT Libraries Government Documents Department
The influence of structural defects on intragranular critical currents of bulk MgB[sub 2].

The influence of structural defects on intragranular critical currents of bulk MgB[sub 2].

Date: January 1, 2002
Creator: Serquis, A. (Adriana); Liao, Xiaozhou; Civale, L. (Leonardo); Zhu, Y. T. (Yuntian Theodore); Coulter, J. Y. (James Y.); Peterson, D. E. (Dean E.) et al.
Description: Bulk MgB2 samples were prepared under different synthesis conditions and analyzed by scanning and transmission electron microscopy. The critical current densities were determined from the magnetization versus magnetic field curves of bulk and powder-dispersed-in-epoxy samples. Results show that through a slow cooling process, the oxygen dissolved in bulk MgB2 at high synthesis temperatures can segregate and form nanometer-sized coherent precipitates of Mg(B,O)2 in the MgB2 matrix. Magnetization measurements indicate that these precipitates act as effective flux pinning centers and therefore significantly improve the intra-grain critical current density and its field dependence.
Contributing Partner: UNT Libraries Government Documents Department
Direct FuelCell/Turbine Power Plant

Direct FuelCell/Turbine Power Plant

Date: September 30, 2008
Creator: Ghezel-Ayagh, Hossein
Description: This report summarizes the progress made in development of Direct FuelCell/Turbine (DFC/T{reg_sign}) power plants for generation of clean power at very high efficiencies. The DFC/T system employs an indirectly heated Turbine Generator to supplement fuel cell generated power. The concept extends the high efficiency of the fuel cell by utilizing the fuel cell's byproduct heat in a Brayton cycle. Features of the DFC/T system include: electrical efficiencies of up to 75% on natural gas, minimal emissions, reduced carbon dioxide release to the environment, simplicity in design, direct reforming internal to the fuel cell, and potential cost competitiveness with existing combined cycle power plants. Proof-of-concept tests using a sub-MW-class DFC/T power plant at FuelCell Energy's (FCE) Danbury facility were conducted to validate the feasibility of the concept and to measure its potential for electric power production. A 400 kW-class power plant test facility was designed and retrofitted to conduct the tests. The initial series of tests involved integration of a full-size (250 kW) Direct FuelCell stack with a 30 kW Capstone microturbine. The operational aspects of the hybrid system in relation to the integration of the microturbine with the fuel cell, process flow and thermal balances, and control strategies for power ...
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Energy Gaps in the Failed High-Tc Superconductor La_1.875Ba_0.125CuO_4

Energy Gaps in the Failed High-Tc Superconductor La_1.875Ba_0.125CuO_4

Date: May 4, 2010
Creator: He, R.
Description: A central issue on high-T{sub c} superconductivity is the nature of the normal-state gap (pseudogap) in the underdoped regime and its relationship with superconductivity. Despite persistent efforts, theoretical ideas for the pseudogap evolve around fluctuating superconductivity, competing order and spectral weight suppression due to many-body effects. Recently, while some experiments in the superconducting state indicate a distinction between the superconducting gap and pseudogap, others in the normal state, either by extrapolation from high-temperature data or directly from La{sub 1.875}Ba{sub 0.125}CuO{sub 4} (LBCO-1/8) at low temperature, suggest the ground-state pseudogap is a single gap of d-wave form. Here we report angle-resolved photoemission (ARPES) data from LBCO-1/8, collected with improved experimental conditions, that reveal the ground-state pseudogap has a pronounced deviation from the simple d-wave form. It contains two distinct components: a d-wave component within an extended region around the node and the other abruptly enhanced close to the antinode, pointing to a dual nature of the pseudogap in this failed high-T{sub c} superconductor which involves a possible precursor pairing energy scale around the node and another of different but unknown origin near the antinode.
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Photonics Research and Development

Photonics Research and Development

Date: January 15, 2010
Creator: Pookpanratana, Sujitra; Shlayan, Neveen; Venkat, Rama; Das, Bisjwajit; Boehm, Bob; Heske, Clemens et al.
Description: During the period August 2005 through October 2009, the UNLV Research Foundation (UNLVRF), a non-profit affiliate of the University of Nevada, Las Vegas (UNLV), in collaboration with UNLV’s Colleges of Science and Engineering; Boston University (BU); Oak Ridge National Laboratory (ORNL); and Sunlight Direct, LLC, has managed and conducted a diverse and comprehensive research and development program focused on light-emitting diode (LED) technologies that provide significantly improved characteristics for lighting and display applications. This final technical report provides detailed information on the nature of the tasks, the results of the research, and the deliverables. It is estimated that about five percent of the energy used in the nation is for lighting homes, buildings and streets, accounting for some 25 percent of the average home’s electric bill. However, the figure is significantly higher for the commercial sector. About 60 percent of the electricity for businesses is for lighting. Thus replacement of current lighting with solid-state lighting technology has the potential to significantly reduce this nation’s energy consumption – by some estimates, possibly as high as 20%. The primary objective of this multi-year R&D project has been to develop and advance lighting technologies to improve national energy conversion efficiencies; reduce heat load; ...
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The mechanical design of a proton microscope for radiography at 800 MeV

The mechanical design of a proton microscope for radiography at 800 MeV

Date: January 1, 2003
Creator: Valdiviez, R. (Robert); Sigler, F. E. (Floyd E.); Barlow, D. B. (David B.); Blind, B. (Barbara); Jason, A. J. (Andrew J.); Mottershead, C. T. et al.
Description: A proton microscope has been developed for radiography applications using the 800-MeV linear accelerator at the Los Alamos Neutron Science Center (LANSCE). The microscope provides a magnified image of a static device, or of a dynamic event such as a high-speed projectile impacting a target. The microscope assembly consists primarily of four Permanent Magnet Quadrupoles (PMQ's) that are supported on movable platforms. The platform supports, along with the rest of the support structure, are designed to withstand the residual dynamic loads that are expected from the dynamic tests. This paper covers the mechanical design of the microscope assembly, including the remote positioning system that allows for fine-tuning the focus of an object being imaged.
Contributing Partner: UNT Libraries Government Documents Department
Support of Gulf of Mexico Hydrate Research Consortium: Activities of Support Establishment of a Sea Floor Monitoring Station Project

Support of Gulf of Mexico Hydrate Research Consortium: Activities of Support Establishment of a Sea Floor Monitoring Station Project

Date: May 31, 2008
Creator: Woolsey, J. Robert; McGee, Thomas & Lutken, Carol
Description: The Gulf of Mexico Hydrates Research Consortium (GOM-HRC) was established in 1999 to assemble leaders in gas hydrates research that shared the need for a way to conduct investigations of gas hydrates and their stability zone in the Gulf of Mexico in situ on a more-or-less continuous basis. The primary objective of the group is to design and emplace a remote monitoring station or sea floor observatory (SFO) on the sea floor in the northern Gulf of Mexico, in an area where gas hydrates are known to be present at, or just below, the sea floor and to discover the configuration and composition of the subsurface pathways or 'plumbing' through which fluids migrate into and out of the hydrate stability zone (HSZ) to the sediment-water interface. Monitoring changes in this zone and linking them to coincident and perhaps consequent events at the seafloor and within the water column is the eventual goal of the Consortium. This mission includes investigations of the physical, chemical and biological components of the gas hydrate stability zone - the sea-floor/sediment-water interface, the near-sea-floor water column, and the shallow subsurface sediments. The eventual goal is to monitor changes in the hydrate stability zone over time. Establishment ...
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Observations on Faults and Associated Permeability Structures in Hydrogeologic Units at the Nevada Test Site

Observations on Faults and Associated Permeability Structures in Hydrogeologic Units at the Nevada Test Site

Date: March 30, 2009
Creator: Prothro, Lance B.; Drellack, Sigmund L.; Haugstad, Dawn N.; Huckins-Gang, Heather E. & Townsend, Margaret J.
Description: Observational data on Nevada Test Site (NTS) faults were gathered from a variety of sources, including surface and tunnel exposures, core samples, geophysical logs, and down-hole cameras. These data show that NTS fault characteristics and fault zone permeability structures are similar to those of faults studied in other regions. Faults at the NTS form complex and heterogeneous fault zones with flow properties that vary in both space and time. Flow property variability within fault zones can be broken down into four major components that allow for the development of a simplified, first approximation model of NTS fault zones. This conceptual model can be used as a general guide during development and evaluation of groundwater flow and contaminate transport models at the NTS.
Contributing Partner: UNT Libraries Government Documents Department
A Study of Catalytic Oxidation and Oxide Adsorption for the Removal of Tritium from Air

A Study of Catalytic Oxidation and Oxide Adsorption for the Removal of Tritium from Air

Date: December 21, 1972
Creator: Bixel, John C. & Kershner, Carl J.
Description: An apparatus and procedure were developed for studying the containment of tritium using catalytic conversion to the oxide followed by oxide adsorption. Data were obtained on the catalytic oxidation of elemental tritium and tritiated volatile hydrocarbons from pump oils between 23 and 538 degrees C. Oxidation efficiencies as high as 99.99997% (decontamination factor = 3.3 million) were obtained for total tritium levels of 1 ppm and a tritiated hydrocarbon level of approximately 0.2 ppb. In addition, a mathematical study was made to derive equations for the conceptual design of an "Emergency Containment System" for containment of tritium following an accidental release to room air.
Contributing Partner: UNT Libraries Government Documents Department
Notification of Concurrence - K-25/K-27 D&D Project, ETTP - Change Number of EMWMF Waste Lots in the Waste Handling Plan for Demolition of the K-25 and K-27 Building Structures and Remaining Components Located at the ETTP, Oak Ridge, TN From Two to Three

Notification of Concurrence - K-25/K-27 D&D Project, ETTP - Change Number of EMWMF Waste Lots in the Waste Handling Plan for Demolition of the K-25 and K-27 Building Structures and Remaining Components Located at the ETTP, Oak Ridge, TN From Two to Three

Date: February 11, 2009
Creator: K.D., Trice
Description: Section 5.1 of the approved Waste Handling Plan for Demolition ofthe K-25 and K-2 7 Building Structures and Remaining Components Located at the East Tennessee Technology Park, Oak Ridge, Tennessee (WHP) includes two Environmental Management Waste Management (EMWMF) waste lots: (1) Asbestos-contaminated roofing/transite; and (2) Construction debris, such as nonasbestos roofing, structural steel/miscellaneous metal/equipment, nonradiological piping, wood, and miscellaneous small quantities of concrete. This concurrence form adds an additional EMWMF waste lot 6.47 for lavatory sink drains. Based on an analysis of the building structure characterization data, the only individual building structure with either an analytic carcinogenic or Hazard Index (HI) sum-of-fractions (SOF) greater than 1 is the lavatory sink drains (Table 1). The HI SOF for the lavatory sink drains is 1.34 (Table 2). When all media are combined with the material of construction calculations, the HI SOF is 1.22 (Table 3). However, when the lavatory sink drains are segregated from all other media, the HI SOF is only 0.256, which is well below the EMWMF waste acceptance criteria SOF limit of 1 (Table 4). Given the large volume (124, 625 cubic yards) of other building structure media with a small HI SOF of 0.256 and the small volume ...
Contributing Partner: UNT Libraries Government Documents Department
Integrating externally developed systems for SNS Linac cooling and vacuum.

Integrating externally developed systems for SNS Linac cooling and vacuum.

Date: January 1, 2001
Creator: Marroquin, P. S. (Pilar S.)
Description: External contractors are developing the local cooling and vacuum control systems for the Spallation Neutron Source (SNS) linac. Soon these systems will be integrated into the facility-wide controls system. Allen-Bradley Logix5000 series programmable controllers, populated with appropriate input/output modules, were selected as the local controllers. These controllers will be interfaced to the facility-wide control system via VME systems with PowerPC processors running the Wind River VxWorks operating system and Experimental Physics and Industrial Control System (EPICS) front-end controller software. This paper describes the interface and integration issues driven by project, cooling system and vacuum system requirements and hardware selections.
Contributing Partner: UNT Libraries Government Documents Department
Synchrotron-based high-pressure research in materials science

Synchrotron-based high-pressure research in materials science

Date: June 1, 2016
Creator: Chen, Bin; Lin, Jung-Fu; Chen, Jiuhua; Zhang, Hengzhong & Zeng, Qiaoshi
Description: <title>Abstract</title> <p><fig position='anchor'><graphic href='S088376941600110X_figAb' mime-subtype='jpeg' mimetype='image' position='float' type='simple'/></fig></p>
Contributing Partner: UNT Libraries Government Documents Department
Synchrotron-based high-pressure research in materials science

Synchrotron-based high-pressure research in materials science

Date: June 1, 2016
Creator: Chen, Bin; Lin, Jung-Fu; Chen, Jiuhua; Zhang, Hengzhong & Zeng, Qiaoshi
Description: <title>Abstract</title> <p><fig position='anchor'><graphic href='S088376941600110X_figAb' mime-subtype='jpeg' mimetype='image' position='float' type='simple'/></fig></p>
Contributing Partner: UNT Libraries Government Documents Department
Final Technical Report

Final Technical Report

Date: September 8, 2009
Creator: Stenzel, Reiner & Urrutia, J. Manuel
Description: The nonlinear physics of electron magnetohydrodynamics (EMHD) in plasmas. Time-varying wave magnetic field exceeding the background magnetic field produces highly nonlinear whistler mode since the wave dispersion depends on the total magnetic field. There exists no theory for such whistler modes. The present experimental work is the first one to explore this regime of nonlinear whistlers. A field-reversed configuration has been found which has the same vortex topology as an MHD spheromak, termed a whistler spheromak. Whistler mirrors have compressed and twisted field lines propagating in the whistler mode. Their helicity properties have been studied. Whistler spheromaks and mirrors have different propagation and damping characteristics. Wave collisions have been studied. Head-on collisions of two whistler spheromaks form a stationary field-reversed configuration (FRC) without helicity. When whistler spheromaks are excited the toroidal current flows mainly in the toroidal null line. It is only carried by electrons since ion currents and displacement currents are negligible. A change in the poloidal (axial) magnetic field induces a toroidal electric field which drives the current. Magnetic energy is dissipated and converted into electron kinetic energy. This process is called magnetic reconnection in 2D geometries, which are simplifications for theoretical convenience but rarely occur in nature. ...
Contributing Partner: UNT Libraries Government Documents Department
Synchrotron-based high-pressure research in materials science

Synchrotron-based high-pressure research in materials science

Date: June 1, 2016
Creator: Chen, Bin; Lin, Jung-Fu; Chen, Jiuhua; Zhang, Hengzhong & Zeng, Qiaoshi
Description: <title>Abstract</title> <p><fig position='anchor'><graphic href='S088376941600110X_figAb' mime-subtype='jpeg' mimetype='image' position='float' type='simple'/></fig></p>
Contributing Partner: UNT Libraries Government Documents Department
Synchrotron-based high-pressure research in materials science

Synchrotron-based high-pressure research in materials science

Date: June 1, 2016
Creator: Chen, Bin; Lin, Jung-Fu; Chen, Jiuhua; Zhang, Hengzhong & Zeng, Qiaoshi
Description: <title>Abstract</title> <p><fig position='anchor'><graphic href='S088376941600110X_figAb' mime-subtype='jpeg' mimetype='image' position='float' type='simple'/></fig></p>
Contributing Partner: UNT Libraries Government Documents Department
A metamodel-based approach to model validation for nonlinear finite element simulations

A metamodel-based approach to model validation for nonlinear finite element simulations

Date: January 1, 2001
Creator: Doebling, S. W. (Scott W.); Hemez, F. M. (François M.); Schultze, J. F. (John F.) & Cundy, A. L. (Amanda L.)
Description: Metamodeling, also known as response surface analysis, is the de facto standard for mathematical representation of complex phenomena in many fields, especially when first principles physical relationships are not well-defined, e.g. economics, climatology, and government policy. Metamodels provide a computationally efficient, low-dimension relationship for studying the behavior of a physical system. They can be used for understanding the physical system, predicting its response, optimizing its design or the parameters in a physical model, and performing verification and validation. Metamodels can be derived from simulation results or fit directly to observed test data. In structural dynamics, typical practice is to develop a first-principles-based model such as a finite element model to study the behavior of the system. However, it is common that the features of interest in a structural dynamics simulation are relatively low order (e.g. first few modal frequencies, peak acceleration at certain locations) and sensitive to relatively few model and simulation parameters. In these cases, metamodeling provides a convenient format to facilitate activities of model validation, including parameter screening, sensitivity analysis [3], uncertainty analysis, and test/analysis correlation. This paper describes the creation of metamodels, and presents some examples of how metamodels can be employed to facilitate model validation for ...
Contributing Partner: UNT Libraries Government Documents Department
DANCE : a 4[pi] barium fluoride detector for measuring neutron capture on unstable nuclei /.

DANCE : a 4[pi] barium fluoride detector for measuring neutron capture on unstable nuclei /.

Date: January 1, 2002
Creator: Ullmann, J. L. (John L.); Haight, Robert C.; Hunt, L. F. (Lloyd F.); Reifarth, R. (Rene); Rundberg, R. S. (Robert S.); Bredeweg, T. A. (Todd A) et al.
Description: Measurements of neutron capture on unstable nuclei are important for studies of s-process nucleosynthesis, nuclear waste transmutation, and stewardship science. A 160-element, 4{pi} barium fluoride detector array, and associated neutron flight path, is being constructed to make capture measurements at the moderated neutron spallation source at LANSCE. Measurements can be made on as little as 1 mg of sample material over energies from near thermal to near 100 keV. The design of the DANCE array is described and neutron flux measurements from flight path commissioning are shown. The array is expected to be complete by the end of 2002.
Contributing Partner: UNT Libraries Government Documents Department
Multiscale simulations of alloy phase stability

Multiscale simulations of alloy phase stability

Date: January 1, 2002
Creator: Stan, M. (Marius); Baskes, M. I. (Michael I.); Valone, S. M. (Steven M.); Chen, S. P. (Shao-Ping) & Kothe, D. B. (Douglas B.)
Description: First principles, atomic scale and continuum level models are combined to predict thermodynamic properties of alloys and stability of phases. Many-body interactions, as well as vacancies, defects, and non-stoichiometry are included in the modeling process and the structural stability of hypothetical phases is evaluated. The resulted thermodynamic functions and phase diagrams are integrated in a casting simulation computer program. The process of relating microscopic modeling results to the macroscopic heat transfer and phase equilibrium calculations is detailed to emphasize the self-consistency of the approach and to identify the potential sources of errors. The sequence: data acquisition, modeling, prediction experimental validation, is illustrated for several recent results in actinide based alloys.
Contributing Partner: UNT Libraries Government Documents Department
Synchrotron-based high-pressure research in materials science

Synchrotron-based high-pressure research in materials science

Date: June 1, 2016
Creator: Chen, Bin; Lin, Jung-Fu; Chen, Jiuhua; Zhang, Hengzhong & Zeng, Qiaoshi
Description: <title>Abstract</title> <p><fig position='anchor'><graphic href='S088376941600110X_figAb' mime-subtype='jpeg' mimetype='image' position='float' type='simple'/></fig></p>
Contributing Partner: UNT Libraries Government Documents Department
Synchrotron-based high-pressure research in materials science

Synchrotron-based high-pressure research in materials science

Date: June 1, 2016
Creator: Chen, Bin; Lin, Jung-Fu; Chen, Jiuhua; Zhang, Hengzhong & Zeng, Qiaoshi
Description: <title>Abstract</title> <p><fig position='anchor'><graphic href='S088376941600110X_figAb' mime-subtype='jpeg' mimetype='image' position='float' type='simple'/></fig></p>
Contributing Partner: UNT Libraries Government Documents Department
Synchrotron-based high-pressure research in materials science

Synchrotron-based high-pressure research in materials science

Date: June 1, 2016
Creator: Chen, Bin; Lin, Jung-Fu; Chen, Jiuhua; Zhang, Hengzhong & Zeng, Qiaoshi
Description: <title>Abstract</title> <p><fig position='anchor'><graphic href='S088376941600110X_figAb' mime-subtype='jpeg' mimetype='image' position='float' type='simple'/></fig></p>
Contributing Partner: UNT Libraries Government Documents Department
DNC / CRONOS Deployment 703040

DNC / CRONOS Deployment 703040

Date: March 13, 2009
Creator: Kanies, Tim
Description: KCP tested a classified DNC / CRONOS as a pilot project in FY06 in the Reservoir Machining area. The pilot proved as a successful way to distribute classified NC Programs to machines that run both classified and unclassified programs securely. This also allows for elimination of CREM for machines which had to swap out classified and unclassified hard drives previously. This project’s purpose is to rollout this technology to the remaining machining areas, predominately Department B, Department C and Department A. Associated with this activity is the modification of business practices in the Tool Room / Model Shop areas and to address licensing issues for MASTERCAM to incorporate DNC CRONOS.
Contributing Partner: UNT Libraries Government Documents Department