Beam Test of Gamma-ray Large Area Space Telescope Components (open access)

Beam Test of Gamma-ray Large Area Space Telescope Components

A beam test of GLAST (Gamma-ray Large Area Space Telescope) components was performed at the Stanford Linear Accelerator Center in October, 1997. These beam test components were simple versions of the planned light hardware. Results on the performance of the tracker, calorimeter, and anticoincidence charged particle veto are presented.
Date: May 27, 1999
Creator: Bloom, Elliott D
Object Type: Report
System: The UNT Digital Library
Properties of RR Lyrae stars in the Inner Regions of the Large Magellanic Cloud (open access)

Properties of RR Lyrae stars in the Inner Regions of the Large Magellanic Cloud

We present the radial velocities, metallicities and the K-band magnitudes of 74 RR Lyrae stars in the inner regions of the LMC. The intermediated resolution spectra and the infrared images were obtained with FORS1 at the ESO VLT and with the SOFI infrared imager at the ESO NTT. The best 43 RR Lyrae with measured velocities yield an observed velocity dispersion of {sigma}=61{+-} 7 km s{sup -1}. We obtain a true LMC RR Lyrae velocity dispersion of {sigma}=53 km s{sup -1}, which is higher than the velocity dispersion of any other LMC population previously measured. This is the first empirical evidence for a kinematically hot, metal-poor halo in the LMC as discussed in Minniti et al. (2003). Using Layden's (1994) modification for the {Delta}S method we measured the metallicity for 23 of our stars. The mean value is [Fe/H]=-1.46{+-}0.09 dex. The absolute magnitudes M{sub v} and M{sub K} of RR Lyrae stars are linear functions of metallicity. In the V band, our data agree with the Olech et al. (2003) relation, in the K band the slope is flatter. The average apparent V luminosity of 70 RR Lyrae stars is <V>=19.45{+-}0.04 and the average K luminosity of 37 RR Lyrae …
Date: May 27, 2004
Creator: Borissova, J; Minniti, D; Rejkuba, M; Alves, D; Cook, K H & Freeman, K C
Object Type: Article
System: The UNT Digital Library
Decommissioning plan for the National Ignition Facility (open access)

Decommissioning plan for the National Ignition Facility

The National Ignition Facility (NIF) is a US Department of Energy inertial confinement laser fusion experimental facility currently under construction at the Lawrence Livermore National Laboratory (LLNL). To ensure that decontamination and decommissioning (D&D) issues at the end-of-life are manageable, this subject has received attention from an early stage. This paper summarizes the NIF D&D issues, and the status of the D&D plan.
Date: May 27, 1998
Creator: Brereton, S.
Object Type: Article
System: The UNT Digital Library
Safety and environmental process for the design and construction of the National Ignition Facility (open access)

Safety and environmental process for the design and construction of the National Ignition Facility

The National Ignition Facility (NIF) is a U.S. Department of Energy (DOE) laser fusion experimental facility currently under construction at the Lawrence Livermore National Laboratory (LLNL). This paper describes the safety and environmental processes followed by NIF during the design and construction activities.
Date: May 27, 1998
Creator: Brereton, S.J., LLNL
Object Type: Article
System: The UNT Digital Library
BIOTIGER, A NATURAL MICROBIAL PRODUCT FOR ENHANCED HYDROCARBON RECOVERY FROM OIL SANDS. (open access)

BIOTIGER, A NATURAL MICROBIAL PRODUCT FOR ENHANCED HYDROCARBON RECOVERY FROM OIL SANDS.

BioTiger{trademark} is a unique microbial consortia that resulted from over 8 years of extensive microbiology screening and characterization of samples collected from a century-old Polish waste lagoon. BioTiger{trademark} shows rapid and complete degradation of aliphatic and aromatic hydrocarbons, produces novel surfactants, is tolerant of both chemical and metal toxicity and shows good activity at temperature and pH extremes. Although originally developed and used by the U.S. Department of Energy for bioremediation of oil-contaminated soils, recent efforts have proven that BioTiger{trademark} can also be used to increase hydrocarbon recovery from oil sands. This enhanced ex situ oil recovery process utilizes BioTiger{trademark} to optimize bitumen separation. A floatation test protocol with oil sands from Ft. McMurray, Canada was used for the BioTiger{trademark} evaluation. A comparison of hot water extraction/floatation test of the oil sands performed with BioTiger{trademark} demonstrated a 50% improvement in separation as measured by gravimetric analysis in 4 h and a five-fold increase at 25 hr. Since BioTiger{trademark} performs well at high temperatures and process engineering can enhance and sustain metabolic activity, it can be applied to enhance recovery of hydrocarbons from oil sands or other complex recalcitrant matrices.
Date: May 27, 2008
Creator: Brigmon, R; Topher Berry, T; Whitney Jones, W & Charles Milliken, C
Object Type: Article
System: The UNT Digital Library
LOW-RADIOACTIVITY-LEVEL WASTE TREATMENT. PART II. PILOT PLANT DEMONSTRATION OF THE REMOVAL OF ACTIVITY FROM LOW-LEVEL PROCESS WASTES BY A SCAVENGING-PRECIPITATION ION-EXCHANGE PROCESS (open access)

LOW-RADIOACTIVITY-LEVEL WASTE TREATMENT. PART II. PILOT PLANT DEMONSTRATION OF THE REMOVAL OF ACTIVITY FROM LOW-LEVEL PROCESS WASTES BY A SCAVENGING-PRECIPITATION ION-EXCHANGE PROCESS

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Date: May 27, 1963
Creator: Brooksbank, R E; Browder, F N; Holcomb, R R & Whitson, W R
Object Type: Report
System: The UNT Digital Library
The secure, transportable, autonomous reactor (STAR): a small proliferation-resistant reactor system for developing countries (open access)

The secure, transportable, autonomous reactor (STAR): a small proliferation-resistant reactor system for developing countries

The Secure, Transportable, Autonomous Reactor (STAR), is an integrated concept for a small, proliferation-resistant nuclear power system capable of meeting the growing power demands of many regions of the developing world. The STAR approach builds on earlier work investigating the features required for implementation of such a system. The STAR approach includes establishing overall system requirements, conducting research into issues common to four reactor concepts (gas, liquid metal, light water and molten salt), and defining and performing the down-selection to a preferred concept that will serve as the basis for continued development leading to an eventual prototype. The paper indicates that a number of unique and distinguishing innovations are needed to both meet the energy demands of most of the world's developing regions and address growing nuclear proliferation concerns. These technical innovations form much of the basis underlying the STAR concept and include: eliminating on-site refueling and fuel access; incorporating a systems approach to nuclear energy supply and infrastructure design, with all aspects of equipment life, fuel and waste cycles included; small unit size enabling transportability; replaceable standardized modular design; resilient and robust design concepts leading to large safety margins, high reliability and reduced maintenance; simplicity in operation with reliance …
Date: May 27, 1999
Creator: Brown, N W; Hassberger, J A & Smith, C F
Object Type: Article
System: The UNT Digital Library
The Secure, Transportable, Autonomous Reactor System (open access)

The Secure, Transportable, Autonomous Reactor System

The Secure, Transportable, Autonomous Reactor (STAR) system is a development architecture for implementing a small nuclear power system, specifically aimed at meeting the growing energy needs of much of the developing world. It simultaneously provides very high standards for safety, proliferation resistance, ease and economy of installation, operation, and ultimate disposition. The STAR system accomplishes these objectives through a combination of modular design, factory manufacture, long lifetime without refueling, autonomous control, and high reliability.
Date: May 27, 1999
Creator: Brown, N.W.; Hassberger, J.A.; Smith, C.; Carelli, M.; Greenspan, E.; Peddicord, K.L. et al.
Object Type: Article
System: The UNT Digital Library
Results of Compact Stellarator Engineering Trade Studies (open access)

Results of Compact Stellarator Engineering Trade Studies

number of technical requirements and performance criteria can drive stellarator costs, e.g., tight tolerances, accurate coil positioning, low aspect ratio (compactness), choice of assembly strategy, metrology, and complexity of the stellarator coil geometry. With the completion of a seven-year design and construction effort of the National Compact Stellarator Experiment (NCSX) it is useful to interject the NCSX experience along with the collective experiences of the NCSX stellarator community to improving the stellarator configuration. Can improvements in maintenance be achieved by altering the stellarator magnet configuration with changes in the coil shape or with the combination of trim coils? Can a mechanical configuration be identified that incorporates a partial set of shaped fixed stellarator coils along with some removable coil set to enhance the overall machine maintenance? Are there other approaches that will simplify the concepts, improve access for maintenance, reduce overall cost and improve the reliability of a stellarator based power plant? Using ARIES-CS and NCSX as reference cases, alternative approaches have been studied and developed to show how these modifications would favorably impact the stellarator power plant and experimental projects. The current status of the alternate stellarator configurations being developed will be described and a comparison made to the …
Date: May 27, 2009
Creator: Brown, Tom; Bromberg, L. & Cole, M.
Object Type: Article
System: The UNT Digital Library
Experimental studies of a large heterogeneous LMFBR benchmark core, ZPPR-13A (open access)

Experimental studies of a large heterogeneous LMFBR benchmark core, ZPPR-13A

The ZPPR-13 program provides basic physics information for testing calculations of radially heterogeneous cores of about 700 MWe size. ZPPR-13 is part of the JUPITER cooperative program between Japan and the US. The results are presented of measurements and analysis for the first assembly, ZPPR-13A. These are the first data for heterogeneous cores of this size available in the US and complement results from ZPPR-9, a conventional LMFBR of similar size.
Date: May 27, 1983
Creator: Brumbach, S. B.; Collins, P. J.; Carpenter, S. G.; Suzuki, S. & Kawashima, M.
Object Type: Article
System: The UNT Digital Library
Progress of the AVNG System - Attribute Verification System With Information Barriers for Mass and Isotopics Measurements (open access)

Progress of the AVNG System - Attribute Verification System With Information Barriers for Mass and Isotopics Measurements

An attribute verification system (AVNG) with information barriers for mass and isotopics measurements has been designed and its fabrication is nearly completed. The AVNG is being built by scientists at the Russian Federal Nuclear Center-VNIIEF, with support of Los Alamos National Laboratory (LANL) and Lawrence Livermore National Laboratory (LLNL). Such a system could be used to verify the presence of several unclassified attributes of classified material with no classified information release. The system is comprised of a neutron multiplicity counter and gamma-spectrometry system based on a high purity germanium gamma detector (nominal relative efficiency {at} 1332 keV 50%) and digital gamma-ray spectrometer DSPEC{sup PLUS}. The neutron multiplicity counter is a three ring counter with 164 {sup 3}He tubes. The system was designed to measure prototype containers 491 mm in diameter and 503 mm high. This paper provides a brief history of the project and documents the progress of this effort with drawings and photographs.
Date: May 27, 2005
Creator: Budnikov, D.; Bulatov, M.; Jarikhine, I.; Lebedev, B.; Livke, A.; Modenov, A. et al.
Object Type: Article
System: The UNT Digital Library
Sheet rod tests (open access)

Sheet rod tests

The overall testing of the vertical sheet rod system is a comprehensive program which has been divided into several phases. These phases are presented here, with a short resume of the testing required under each phase, to enable the formulation of the project proposal for the complete test program. It is intended that very detailed test requests will be issued for the separate phases as data from previous tests and further design studies indicate the exact information or data desired from a particular test.
Date: May 27, 1949
Creator: Burns, C. M.
Object Type: Report
System: The UNT Digital Library
Limit on the rare decay B {yields} {mu}{sup +}{mu}{sup {minus}} K{sup {plus_minus}} (open access)

Limit on the rare decay B {yields} {mu}{sup +}{mu}{sup {minus}} K{sup {plus_minus}}

We report on a search for flavor-changing neutral current decays of B mesons into {mu}{mu}K{sup {plus_minus}} using data obtained in the Collider Detector at Fermilab (CDF) 1992--1993 data taking run. To reduce the amount of background in our data we use precise tracking information from the CDF silicon vertex detector to pinpoint the location of the decay vertex of the B candidate, and accept only events which have a large decay time. We compare this data to a B meson signal obtained in a similar fashion, but where the muon pears originate from {psi} decays, and calculate the relative branching ratios. In absence of any indication of flavor-changing neutral current decay we set an upper limit on the branching ratio of 3.2 {times} 10{sup {minus}1}, which is consistent with Standard Model expectations but leaves little room for non-standard physics.
Date: May 27, 1994
Creator: CDF Collaboration
Object Type: Article
System: The UNT Digital Library
Evaluating risk using bounding calculations and limited data (open access)

Evaluating risk using bounding calculations and limited data

This paper describes a methodology for estimating the potential risk to workers and the public from igniting organic solvents in any of the 177 underground waste storage tanks at the Hanford Site in southeastern Washington state. The Hanford Site is one of the U.S. Department of Energy's former production facilities for nuclear materials. The tanks contain mixed radioactive wastes. Risk is measured by calculating toxicological and radiological accident consequences and frequencies and comparing the results to established regulatory guidelines. Available sample data is insufficient to adequately characterize the waste and solvent, so a model that maximizes releases from the tanks (bounding case) is used. Maximizing releases (and thus consequences) is a standard technique used in safety analysis to compensate for lack of information. The model predicts bounding values of fire duration, the time at which the fire extinguishes because of lack of oxygen, and a pressure history of a fire in a tank. The model output is used to calculate mass and volume release rates of material from the tanks. The mass and volume release rates permit calculation of radiological and toxicological consequences. The resulting consequence calculations demonstrate that risk from an organic solvent fire in the tanks is within …
Date: May 27, 1999
Creator: COWLEY, W.L.
Object Type: Report
System: The UNT Digital Library
Evaporation of Hanford Tank Sample AN-107 Mixed with Recycles (open access)

Evaporation of Hanford Tank Sample AN-107 Mixed with Recycles

A proof-of-technology demonstration for the Hanford River Protection Project (RPP) Hanford Tank Waste Treatment and Immobilization Plant (WTP) was performed by the Savannah River Technology Center (SRTC) at the Savannah River Site (SRS). As part of this demonstration, a sample of as-received Tank AN-107 waste was mixed with surrogate recycle and then evaporated to concentrate the mixture. A second test was conducted in which surrogate recycle was initially concentrated, then mixed with as-received AN-107 waste. Both of these tests were the first studies conducted that investigated the potential impact of secondary-waste recycle streams on the evaporation process using actual radioactive waste feed.
Date: May 27, 2004
Creator: CRAWFORD, C
Object Type: Report
System: The UNT Digital Library
Twos in two photon physics: A convention for the. gamma. gamma. * width of a spin-one particle (open access)

Twos in two photon physics: A convention for the. gamma. gamma. * width of a spin-one particle

The two conventions for the {gamma}{gamma}* width of a spin-one resonance are discussed. It is shown that the more reasonable one is the one that gives the larger experimental value. 5 refs.
Date: May 27, 1988
Creator: Cahn, R.N.
Object Type: Article
System: The UNT Digital Library
ARTI Refrigerant Database (open access)

ARTI Refrigerant Database

The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.
Date: May 27, 1994
Creator: Calm, J. M.
Object Type: Report
System: The UNT Digital Library
Instrumented SSH (open access)

Instrumented SSH

NERSC recently undertook a project to access and analyze Secure Shell (SSH) related data. This includes authentication data such as user names and key fingerprints, interactive session data such as keystrokes and responses, and information about noninteractive sessions such as commands executed and files transferred. Historically, this data has been inaccessible with traditional network monitoring techniques, but with a modification to the SSH daemon, this data can be passed directly to intrusion detection systems for analysis. The instrumented version of SSH is now running on all NERSC production systems. This paper describes the project, details about how SSH was instrumented, and the initial results of putting this in production.
Date: May 27, 2009
Creator: Campbell, Scott & Campbell, Scott
Object Type: Report
System: The UNT Digital Library
Beam based measurements of hysteresis effects in Fermilab main injector magnets (open access)

Beam based measurements of hysteresis effects in Fermilab main injector magnets

Operation of the Fermilab Main Injector is sensitive to magnetic field differences due to hysteretic effects. Measurements using the beam are reported with various current ramps. This will provide magnetic field information for accelerator operations with better ramp control than is available from magnet test facility data. This makes possible improved low field reproducibility with mixed 120 GeV and 150 GeV operation of the Main Injector.
Date: May 27, 2003
Creator: Capista, Bruce C. Brown and David P
Object Type: Article
System: The UNT Digital Library
Binuclear Non-heme Iron Catalysts (open access)

Binuclear Non-heme Iron Catalysts

This project involved the investigation of the ability of non-heme iron metalloenzyme reactivity model complexes to catalyze the oxidation of alkane and arene molecules. The objectives were to synthesize a series of non-heme mononuclear and dinuclear iron complexes, characterize their electronic structure and reactivity properties, characterize intermediates formed during oxygen atom transfer chemistry, and elucidate the mechanisms and specificity of the reactions.
Date: May 27, 2004
Creator: Caradonna, J. P.
Object Type: Report
System: The UNT Digital Library
Issues in the use of Weapons-Grade MOX Fuel in VVER-1000 Nuclear Reactors: Comparison of UO2 and MOX Fuels (open access)

Issues in the use of Weapons-Grade MOX Fuel in VVER-1000 Nuclear Reactors: Comparison of UO2 and MOX Fuels

The purpose of this report is to quantify the differences between mixed oxide (MOX) and low-enriched uranium (LEU) fuels and to assess in reasonable detail the potential impacts of MOX fuel use in VVER-1000 nuclear power plants in Russia. This report is a generic tool to assist in the identification of plant modifications that may be required to accommodate receiving, storing, handling, irradiating, and disposing of MOX fuel in VVER-1000 reactors. The report is based on information from work performed by Russian and U.S. institutions. The report quantifies each issue, and the differences between LEU and MOX fuels are described as accurately as possible, given the current sources of data.
Date: May 27, 2005
Creator: Carbajo, J. J.
Object Type: Report
System: The UNT Digital Library
Parametric design study of tandem mirror fusion reactors (open access)

Parametric design study of tandem mirror fusion reactors

The parametric design study of the tandem mirror reactor (TMR) is described. The results of this study illustrate the variation of reactor characteristics with changes in the independent design parameters, reveal the set of design parameters which minimizes the cost of the reactor, and show the sensitivity of the optimized design to physics and technological uncertainties. The total direct capital cost of an optimized 1000 MWe TMR is estimated to be $1300/kWe. The direct capital cost of a 2000 MWe plant is less than $1000/kWe.
Date: May 27, 1977
Creator: Carlson, G. A.
Object Type: Article
System: The UNT Digital Library
Nonequilibrium THz Conductivity of Bi2Sr2CaCu2O8+d (open access)

Nonequilibrium THz Conductivity of Bi2Sr2CaCu2O8+d

Using high sensitivity visible-pump/THz-probe spectroscopywe investigate the dynamics of the complex optical conductivity inoptimally-doped Bi2Sr2CaCu2O8+d films directly after photoexcitation. Thephotoinduced change in the imaginary part, indicative of a reduction inthe superconducting condensate density, saturates at higherlaser-fluences and shows a complete destruction of thecondensate.
Date: May 27, 2003
Creator: Carnahan, M. A.; Kaindl, R. A.; Orenstein, J.; Chemla, D. S.; Oh, S. & Eckstein, J. N.
Object Type: Article
System: The UNT Digital Library
Finite difference micromagnetic simulation with self-consistent currents and smooth surfaces (open access)

Finite difference micromagnetic simulation with self-consistent currents and smooth surfaces

A micromagnetic algorithm has been developed using the finite difference method (FDM). Elliptic field equations are solved on the mesh using the efficient Dynamic Alternating Direction Implicit method. Smooth surfaces have been included in the FDM formulation so structures of irregular shape can be modeled. The current distribution and temperature of devices are also calculated. Keywords: Micromagnetic simulation, Magnetic dots, Read heads, Thermal Effects
Date: May 27, 1999
Creator: Cerjan, C.; Gibbons, M. R.; Hewett, D. W. & Parker, G.
Object Type: Article
System: The UNT Digital Library