Special topics reports for the reference tandem mirror fusion breeder. Volume 5. Neutronic issues and optimization (open access)

Special topics reports for the reference tandem mirror fusion breeder. Volume 5. Neutronic issues and optimization

More rigorous nuclear analysis, including the treatment of resonance self-shielding effects coupled with an optimization procedure, has resulted in improved performance of the Be/Li/Th blanket. Net U-233 breeding ratio has increased 36% (to 0.84) while at a U/Th ratio of 0.25 a/o energy multiplication has increased 12% (to 2.1) compared with earlier results.
Date: March 29, 1985
Creator: Lee, J. D. & Bandini, B. R.
Object Type: Report
System: The UNT Digital Library
Eclipsing binary stars in the Large and Small Magellanic Clouds from the MACHO project: The Sample (open access)

Eclipsing binary stars in the Large and Small Magellanic Clouds from the MACHO project: The Sample

We present a new sample of 4634 eclipsing binary stars in the Large Magellanic Cloud (LMC), expanding on a previous sample of 611 objects and a new sample of 1509 eclipsing binary stars in the Small Magellanic Cloud (SMC), that were identified in the light curve database of the MACHO project. We perform a cross correlation with the OGLE-II LMC sample, finding 1236 matches. A cross correlation with the OGLE-II SMC sample finds 698 matches. We then compare the LMC subsamples corresponding to center and the periphery of the LMC and find only minor differences between the two populations. These samples are sufficiently large and complete that statistical studies of the binary star populations are possible.
Date: March 29, 2007
Creator: Faccioli, L.; Alcock, C.; Cook, K.; Prochter, G.; Protopapas, P. & Syphers, D.
Object Type: Article
System: The UNT Digital Library
Purgatorio - A new implementation of the Inferno algorithm (open access)

Purgatorio - A new implementation of the Inferno algorithm

For astrophysical applications, as well as modeling laser-produced plasmas, there is a continual need for equation-of-state data over a wide domain of physical conditions. This paper presents algorithmic aspects for computing the Helmholtz free energy of plasma electrons for temperatures spanning from a few Kelvin to several KeV, and densities ranging from essentially isolated ion conditions to such large compressions that most bound orbitals become delocalized. The objective is high precision results in order to compute pressure and other thermodynamic quantities by numerical differentiation. This approach has the advantage that internal thermodynamic self-consistency is ensured, regardless of the specific physical model, but at the cost of very stringent numerical tolerances for each operation. The computational aspects we address in this paper are faced by any model that relies on input from the quantum mechanical spectrum of a spherically symmetric Hamiltonian operator. The particular physical model we employ is that of INFERNO; of a spherically averaged ion embedded in jellium. An overview of PURGATORIO, a new implementation of the INFERNO equation of state model, is presented. The new algorithm emphasizes a novel decimation scheme for automatically resolving the structure of the continuum density of states, circumventing limitations of the pseudo-R matrix …
Date: March 29, 2005
Creator: Wilson, B; Sonnad, V; Sterne, P & Isaacs, W
Object Type: Article
System: The UNT Digital Library
Dynamic molecular imaging of cardiac innervation using a dual headpinhole SPECT system (open access)

Dynamic molecular imaging of cardiac innervation using a dual headpinhole SPECT system

Typically 123I-MIBG is used for the study of innervation andfunction of the sympathetic nervous system in heart failure. The protocolinvolves two studies: first a planar or SPECT scan is performed tomeasure initial uptake of the tracer, followed some 3-4 hours later byanother study measuring the wash-out of the tracer from the heart. A fastwash-out is indicative of a compromised heart. In this work, a dual headpinhole SPECT system was used for imaging the distribution and kineticsof 123I-MIBG in the myocardium of spontaneous hypertensive rats (SHR) andnormotensive Wistar Kyoto (WKY) rats. The system geometry was calibratedbased on a nonlinear point projection fitting method using a three-pointsource phantom. The angle variation effect of the parameters was modeledwith a sinusoidal function. A dynamic acquisition was performed byinjecting 123I-MIBG into rats immediately after starting the dataacquisition. The detectors rotated continuously performing a 360o dataacquisition every 90 seconds. We applied the factor analysis (FA)methodand region of interest (ROI) sampling method to obtain time activitycurves (TACs)in the blood pool and myocardium and then appliedtwo-compartment modeling to estimate the kinetic parameters. Since theinitial injection bolus is too fast for obtaining a consistenttomographic data set in the first few minutes of the study, we appliedthe FA method directly …
Date: March 29, 2008
Creator: Hu, Jicun; Boutchko, Rostyslav; Sitek, Arkadiusz; Reutter, BryanW.; Huesman, Ronald H. & Gullberg, Grant T.
Object Type: Report
System: The UNT Digital Library
Stragegies to Detect Hidden Geothermal Systems Based on Monitoringand Analysis of CO2 in the Near-Surface Environment (open access)

Stragegies to Detect Hidden Geothermal Systems Based on Monitoringand Analysis of CO2 in the Near-Surface Environment

We investigate the potential for CO2 monitoring in thenear-surface environment as an approach to exploration for hiddengeothermal systems. Numerical simulations of CO2 migration from a modelhidden geothermal system show that CO2 concentrations can reach highlevels in the shallow subsurface even for relatively low CO2 fluxes.Therefore, subsurface measurements offer an advantage over above-groundmeasurements which are affected by winds that rapidly disperse CO2. Tomeet the challenge of detecting geothermal CO2 emissions within thenatural background variability of CO2, we propose an approach thatintegrates available detection and monitoring techniques with statisticalanalysis and modeling.
Date: March 29, 2005
Creator: Lewicki, Jennifer L. & Oldenburg, Curtis M.
Object Type: Article
System: The UNT Digital Library
Membrane composition analysis by imaging mass spectrometry (open access)

Membrane composition analysis by imaging mass spectrometry

Membranes on solid supports offer an ideal format for imaging. Secondary ion mass spectrometry (SIMS) can be used to obtain composition information on membrane-associated components. Using the NanoSIMS50, images of composition variations in membrane domains can be obtained with a lateral resolution better than 100 nm. By suitable calibration, these variations in composition can be translated into a quantitative analysis of the membrane composition. Progress towards imaging small phase-separated lipid domains, membrane-associated proteins and natural biological membranes will be described.
Date: March 29, 2006
Creator: Boxer, S G; Kraft, M L; Longo, M; Hutcheon, I D & Weber, P K
Object Type: Article
System: The UNT Digital Library
BIO-ORGANIC CHEMISTRY QUARTERLY REPORT. December 1962 throughFebruary 1963 (open access)

BIO-ORGANIC CHEMISTRY QUARTERLY REPORT. December 1962 throughFebruary 1963

This report covers the following titles: (1) A versatile solvent to replace phenol for the paper chromatography of radioactive intermediary metabolites; (2) Chromatography of plant lipids on alumina paper; (3) Quinone and pigment composition of chloroplasts and quantasomes from Spinacea oleracea; (4) The lipid composition of chloroplast lamellae from Spinacea oleracea; (5) Metal chelates and photochemistry of flavins; (6) Photoinduced ESR in some solutions of organic electron donors and acceptors; (7) Fluorescence of oriented dye-macromolecule complexes--Theoretical study; (8) Formation of adenine by electron irradiation of methane, ammonia, and water; (9) Uptake of organic compounds by planarians; (10) The planaria: Absorption spectrum, cell disaggregation, and studies on homogenates.
Date: March 29, 1963
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Nuclear Gamma-Ray Spectroscopy at the Limit of Particle Spectroscopy (open access)

Nuclear Gamma-Ray Spectroscopy at the Limit of Particle Spectroscopy

The research project ''Nuclear Gamma-Ray Spectroscopy at the Limit of Particle Stability'' with sponsor ID ''DE-FG02-04ER41334'' started late-summer 2004 and aims at the investigation of highly excited low-spin states of selected key-nuclei in the vicinity of the particle separation threshold by means of high-resolution gamma-ray spectroscopy in electromagnetic excitation reactions. This work addresses nuclear structures with excitation energies close to the binding energy or highly excited off-yrast states in accordance with the NSAC milestones. In 2005 the program was extended towards additional use of virtual photons and theoretical description of the low-lying collective excitations in the well deformed nuclei.
Date: March 29, 2006
Creator: Pietralla, Dr. Norbert
Object Type: Report
System: The UNT Digital Library
METEOROLOGICAL MONITORING PROGRAM, PARTICULATE MATTER AMBIENT AIR QUALITY MONITORING REPORT, JANUARY 1992 THROUGH DECEMBER 1995 (open access)

METEOROLOGICAL MONITORING PROGRAM, PARTICULATE MATTER AMBIENT AIR QUALITY MONITORING REPORT, JANUARY 1992 THROUGH DECEMBER 1995

None
Date: March 29, 1996
Creator: /a, n
Object Type: Report
System: The UNT Digital Library
Borehole Data Package for One CY 2005 CERCLA Well 699-S20-E10, 300-FF-5 Operable Unit, Hanford Site, Washington (open access)

Borehole Data Package for One CY 2005 CERCLA Well 699-S20-E10, 300-FF-5 Operable Unit, Hanford Site, Washington

This report supplies the information obtained during drilling, characterization, and installation of the new groundwater monitoring well. This document also provides a compilation of hydrogeologic and well construction information obtained during drilling, well development, and sample collection/analysis activities.
Date: March 29, 2006
Creator: Williams, Bruce A.; Bjornstad, Bruce N.; Lanigan, David C.; Keller, Jason M. & Rockhold, Mark L.
Object Type: Report
System: The UNT Digital Library
Ultrahigh Efficiency Multiband Solar Cells Final Report forDirector's Innovation Initiative Project DII-2005-1221 (open access)

Ultrahigh Efficiency Multiband Solar Cells Final Report forDirector's Innovation Initiative Project DII-2005-1221

The unique properties of the semiconductor ZnTeO were explored and developed to make multiband solar cells. Like a multijunction cell, multiband solar cells use different energy gaps to convert the majority of the solar spectrum to electrical current while minimizing losses due to heating. Unlike a multijunction cell, this is accomplished within a single material in a multiband cell. ZnTe{sub 1-x}O{sub x} films with x up to 2% were synthesized and shown to have the requisite unique band structure (2 conduction bands) for multiband function. Prototype solar cells based on an n-type ZnTe{sub 1-x}O{sub x} multiband top layer and a p-type ZnTe substrate were fabricated. Contacts to the cell and the series resistance of the substrate were identified as challenges for good electrical performance. Both photovoltage and small photocurrents were demonstrated under AMO illumination. A second semiconductor system, GaN{sub x}As{sub 1-y-x}P{sub y}, was shown to have multiband function. This alloy system may have the greatest potential to realize the promise of high efficiency multiband solar cells because of the relatively advanced technology base that exists for the manufacturing of III-V-alloy-based IC and opto-electronic devices (including multijunction solar cells).
Date: March 29, 2006
Creator: Ager, Joel W., III; Walukiewicz, W. & Yu, Kin Man
Object Type: Report
System: The UNT Digital Library
Space-reactor electric systems: subsystem technology assessment (open access)

Space-reactor electric systems: subsystem technology assessment

This report documents the subsystem technology assessment. For the purpose of this report, five subsystems were defined for a space reactor electric system, and the report is organized around these subsystems: reactor; shielding; primary heat transport; power conversion and processing; and heat rejection. The purpose of the assessment was to determine the current technology status and the technology potentials for different types of the five subsystems. The cost and schedule needed to develop these potentials were estimated, and sets of development-compatible subsystems were identified.
Date: March 29, 1983
Creator: Anderson, R.V.; Bost, D. & Determan, W.R.
Object Type: Report
System: The UNT Digital Library
Space reactor electric systems: system integration studies, Phase 1 report (open access)

Space reactor electric systems: system integration studies, Phase 1 report

This report presents the results of preliminary space reactor electric system integration studies performed by Rockwell International's Energy Systems Group (ESG). The preliminary studies investigated a broad range of reactor electric system concepts for powers of 25 and 100 KWe. The purpose of the studies was to provide timely system information of suitable accuracy to support ongoing mission planning activities. The preliminary system studies were performed by assembling the five different subsystems that are used in a system: the reactor, the shielding, the primary heat transport, the power conversion-processing, and the heat rejection subsystems. The subsystem data in this report were largely based on Rockwell's recently prepared Subsystem Technology Assessment Report. Nine generic types of reactor subsystems were used in these system studies. Several levels of technology were used for each type of reactor subsystem. Seven generic types of power conversion-processing subsystems were used, and several levels of technology were again used for each type. In addition, various types and levels of technology were used for the shielding, primary heat transport, and heat rejection subsystems. A total of 60 systems were studied.
Date: March 29, 1983
Creator: Anderson, R. V.; Bost, D.; Determan, W. R.; Harty, R. B.; Katz, B.; Keshishian, V. et al.
Object Type: Report
System: The UNT Digital Library
Comparison of destructive and nondestructive assay of heterogeneous salt residues (open access)

Comparison of destructive and nondestructive assay of heterogeneous salt residues

To study problems associated with nondestructive assay (NDA) measurements of molten salt residues, a joint study was conducted by the Rocky Flats Plant, Golden, CO and Mound Laboratories, Miamisburg, OH. Extensive NDA measurements were made on nine containers of molten salt residues by both Rocky Flats and Mound followed by dissolution and solution quantification at Rocky Flats. Results of this study verify that plutonium and americium can be measured in such salt residues by a new gamma-ray spectral analysis technique coupled with calorimetry. Biases with respect to the segmented gamma-scan technique were noted.
Date: March 29, 1986
Creator: Fleissner, J.G. & Hume, M.W.
Object Type: Report
System: The UNT Digital Library
Assessment of value-impact associated with the elimination of postulated pipe ruptures from the design basis for nuclear power plants (open access)

Assessment of value-impact associated with the elimination of postulated pipe ruptures from the design basis for nuclear power plants

The US Nuclear Regulatory Commission is proposing to amend the regulations that currently require that the design basis for nuclear power plants include the postulation of dynamic effects from loss of coolant accidents up to and including the double-ended rupture of the largest pipe in the reactor coolant system. Proposed modifications would allow analyses to serve as a sufficient basis for excluding dynamic effects, including but not necessarily limited to pipe whip and jet impingement, associated with specific pipe ruptures. Only dynamic effects would be impacted; current design requirements for containment sizing and discharge capacity of emergency core cooling systems would remain unchanged. This report presents a detailed analysis of value-impact associated with the proposed amendment for PWR reactor coolant loop piping and for BWR recirculation loop piping. The effect of extending application of the proposed rule change to other piping systems is also assessed in a less quantitative manner.
Date: March 29, 1985
Creator: Holman, G.S. & Chou, C.K.
Object Type: Report
System: The UNT Digital Library
Layered granule chute flow near the angle of repose (open access)

Layered granule chute flow near the angle of repose

A natural, two-layered gravity flow of sand can be obtained on chutes inclined at angles slightly above the angle of repose of the sand. The top-surface layer is free-flowing, is thin, and moves rapidly at supercritical velocity. The velocity depends mainly on the character of the sand and the chute inclination angle. The bottom layer is thick and moves more slowly, with the flow controlled by adjustable weirs at the chute exit. The velocity profile in the thick bottom layer is curved; as much as an order of magnitude higher velocity occurs in the upper portion of the layer than occurs along the bottom wall of the chute. This study has applications to the cascade inertial fusion concept.
Date: March 29, 1985
Creator: Pitts, J.H. & Walton, O.R.
Object Type: Article
System: The UNT Digital Library
Savannah River Site computing architecture (open access)

Savannah River Site computing architecture

A computing architecture is a framework for making decisions about the implementation of computer technology and the supporting infrastructure. Because of the size, diversity, and amount of resources dedicated to computing at the Savannah River Site (SRS), there must be an overall strategic plan that can be followed by the thousands of site personnel who make decisions daily that directly affect the SRS computing environment and impact the site's production and business systems. This plan must address the following requirements: There must be SRS-wide standards for procurement or development of computing systems (hardware and software). The site computing organizations must develop systems that end users find easy to use. Systems must be put in place to support the primary function of site information workers. The developers of computer systems must be given tools that automate and speed up the development of information systems and applications based on computer technology. This document describes a proposal for a site-wide computing architecture that addresses the above requirements. In summary, this architecture is standards-based data-driven, and workstation-oriented with larger systems being utilized for the delivery of needed information to users in a client-server relationship.
Date: March 29, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Design of aggressive superconducting TFCX magnet systems (open access)

Design of aggressive superconducting TFCX magnet systems

An investigation of several fundamental limits of machine design indicate that a machine fitting the specifications of the Tokamak Fusion Core Experiment (TFCX) can be built with both a superconducting toroidal field (TF) coil set and a plasma major radius of less than 3.2 m. This small size is achieved by accepting a peak nuclear heat load of 50 (kW)(m/sup -3/) in the TF coin inner leg while operating at a 10-T maximum field with a current density of 35 (A)(mm/sup -2/) in the winding pack. This performance, high by traditional standards, is justified based on developments in forced flow conductor technology using Nb/sub 3/Sn composite superconductors.
Date: March 29, 1985
Creator: Miller, J. R.
Object Type: Article
System: The UNT Digital Library
Composition dependence of fluid thermophysical properties: Theory and modeling (open access)

Composition dependence of fluid thermophysical properties: Theory and modeling

Objectives are studies of equilibrium/nonequilibrium properties of asymmetric fluid mixtures through computer simulation (CS), development of predictive theories of mixture equilibrium properties, development and application of selection algorithm methodology for mixture equations of state, and use of theory to develop new engineering design models for fluid mixtures. Kirwood charging method CS of Lennard-Jones mixtures with large size ratios verified the Kirkwood-Buff/Baxter method of calculating chemical potentials. CS of n-butane showed that the rheology is not a function of system size. A modified stepwise regression algorithm was developed and applied to HFC R134a. An analytical expression was developed for conformal solution size correction for mixtures. The extended corresponding states theory (ECST) can be applied to systems having large polarity differences; an accurate representation was developed of bulk phase properties of water-hydrocarbon systems. It was found how to force ECST to reach the correct virial limit.
Date: March 29, 1993
Creator: Ely, J.F.
Object Type: Report
System: The UNT Digital Library
Nova laser alignment control system (open access)

Nova laser alignment control system

Alignment of the Nova laser requires control of hundreds of optical components in the ten beam paths. Extensive application of computer technology makes daily alignment practical. The control system is designed in a manner which provides both centralized and local manual operator controls integrated with automatic closed loop alignment. Menudriven operator consoles using high resolution color graphics displays overlaid with transport touch panels allow laser personnel to interact efficiently with the computer system. Automatic alignment is accomplished by using image analysis techniques to determine beam references points from video images acquired along the laser chain. A major goal of the design is to contribute substantially to rapid experimental turnaround and consistent alignment results. This paper describes the computer-based control structure and the software methods developed for aligning this large laser system.
Date: March 29, 1984
Creator: Van Arsdall, P.J.; Holloway, F.W.; McGuigan, D.L. & Shelton, R.T.
Object Type: Article
System: The UNT Digital Library
Computer applications and hybrid microcircuits (open access)

Computer applications and hybrid microcircuits

The Kansas City Division of the Bendix Corp. is a manufacturing facility. It uses computer graphics to prepare formal drawings in a specified drawing system. Introduction of a system worked out with Sandia Laboratories resulted in reduced time for through-put, faster processing of changes, and steady (rather than increased) employment figures. The system has been in operation for 27 months. It cost about $300,000, and has been used on printed wiring boards, hybrid microcircuits, and test equipment schematics. This report consists primarily of slides, with little text as such. (RWR)
Date: March 29, 1978
Creator: Sheets, L.
Object Type: Article
System: The UNT Digital Library
Electromagnetic direct implicit PIC simulation (open access)

Electromagnetic direct implicit PIC simulation

Interesting modelling of intense electron flow has been done with implicit particle-in-cell simulation codes. In this report, the direct implicit PIC simulation approach is applied to simulations that include full electromagnetic fields. The resulting algorithm offers advantages relative to moment implicit electromagnetic algorithms and may help in our quest for robust and simpler implicit codes.
Date: March 29, 1983
Creator: Langdon, A. Bruce
Object Type: Article
System: The UNT Digital Library
Fusion-power demonstration. [Next step beyond MFTF-B] (open access)

Fusion-power demonstration. [Next step beyond MFTF-B]

As a satellite to the MARS (Mirror Advanced Reactor Study) a smaller, near-term device has been scoped, called the FPD (Fusion Power Demonstration). Envisioned as the next logical step toward a power reactor, it would advance the mirror fusion program beyond MFTF-B and provide an intermediate step toward commercial fusion power. Breakeven net electric power capability would be the goal such that no net utility power would be required to sustain the operation. A phased implementation is envisioned, with a deuterium checkout first to verify the plasma systems before significant neutron activation has occurred. Major tritium-related facilities would be installed with the second phase to produce sufficient fusion power to supply the recirculating power to maintain the neutral beams, ECRH, magnets and other auxiliary equipment.
Date: March 29, 1983
Creator: Henning, C. D.; Logan, B. G.; Carlson, G. A.; Neef, W. S.; Moir, R. W.; Campbell, R. B. et al.
Object Type: Article
System: The UNT Digital Library
Evaluation of the techniques for end-of-life shutdown of orbiting SNAP reactors (open access)

Evaluation of the techniques for end-of-life shutdown of orbiting SNAP reactors

Two techniques for the end-of-life shutdown of orbiting SNAP reactors are presented. One technique consists of two alternative methods for the destruction of the reactor core. This technique (and others) have been investigated during the past year. A second technique, uses a naturally occurring phenomena, which works on the principle of a low neutron absorbing nuclide decaying to a high neutron absorbing daughter (poison). The present design criteria for the latter technique is that only a small reduction in reactivity should occur during the mission lifetime with the slow build-up of poison eventually shutting down the reactor at some later date. Tritium, an isotope of hydrogen is presented as a parent that appears to meet all of the requirements for such an end-of-life shutdown device. The daughter, He/sup 3/ has a high neutron absorption cross section. The results of a preliminary study of the tritium device are presented.
Date: March 29, 1963
Creator: Jamison, N.K.; Lampl, J. & Oliver, D.G.
Object Type: Report
System: The UNT Digital Library