Resource Type

78 Matching Results

Results open in a new window/tab.

Noncontact material testing using laser energy deposition and interferometry (open access)

Noncontact material testing using laser energy deposition and interferometry

A technique is described for the noncontact testing of materials using laser deposition to generate a stress pulse and interferometry to record the transient surface displacement. The dilatational wave speed can be measured and, in the particular case of rod or plate specimens, sufficient information can be obtained to evaluate the two elastic constants of an isotropic material. Several applications illustrating the advantages of the approach are summarized.
Date: February 6, 1978
Creator: Calder, C.A. & Wilcox, W.W.
System: The UNT Digital Library
Conference on decontamination and decommissioning of nuclear facilities (open access)

Conference on decontamination and decommissioning of nuclear facilities

A brief history of Decontamination and Decommissioning (D and D) experience at the Idaho National Engineering Laboratory is presented as an introduction to the status of current projects. Details are then presented as an introduction to the status of current projects. Details are then presented on a project to remove sodium from some major components of the Hallam reactor and on the Organic Moderated Reactor Experiment (OMRE) decommissioning project. Cost, schedule, waste volume, and other technical data from these projects are presented. In addition, a brief summary of the future INEL D and D program is presented.
Date: February 6, 1979
Creator: Meservey, R.H.
System: The UNT Digital Library
Effect of propagation of coherent pulses on multiple-photon excitation (open access)

Effect of propagation of coherent pulses on multiple-photon excitation

The influence of laser pulse propagation on multiple-photon excitation of many-level absorbers, and the significance of SIRF for SF/sub 6/ dissociation are discussed.
Date: February 6, 1980
Creator: Shore, B. W.; Eberly, J. H. & Konopnicki, M. J.
System: The UNT Digital Library
Electroforming copper targets for RTNS-II (open access)

Electroforming copper targets for RTNS-II

Copper targets used in RTNS II, which is the world's most intense 14-MeV neutron source, contain water cooling channels for temperature control. There are two methods for fabricating these targets: (1) diffusion bonding a copper panel containing photoetched channels to another copper panel, and (2) an electroforming technique which involves filling the photoetched channels with wax, plating thick copper to seal over the channels and then removing the wax. Development of this latter process and results obtained with it are described.
Date: February 6, 1981
Creator: Kelley, W. K.; Dini, J. W. & Logan, C. M.
System: The UNT Digital Library
Structural and thermal requirements for the tandem-mirror fusion-test-facility magnet system (open access)

Structural and thermal requirements for the tandem-mirror fusion-test-facility magnet system

Structural requirements for the magnet system include unique spatial constraints and materials restrictions to meet the operational needs of the unusual configuration. All of the magnets are liquid helium cooled which represents about 1500 tonnes of 4.5 K structure in the vacuum environment of the large vessel. Magnet support structures must satisfy complex load conditions, including electromagnetic (both normal-operating and fault conditions) and seismically induced. Improved plasma confinement, characterized by long particle lifetimes, requires attention to coil alignment and field errors. Continued monitoring of field accuracy and possible adjustment during operation are contemplated. Operating conditions for the magnet system include rapid cooldown and warm-up to minimize down time for maintenance.
Date: February 6, 1981
Creator: VanSant, J. H. & Bulmer, R. H.
System: The UNT Digital Library
Techniques for the generation and monitoring of vapors (open access)

Techniques for the generation and monitoring of vapors

Controlled test atmospheres can be produced using a variety of techniques. Gases are usually generated by using flow dilution methods while vapors are produced by using solvent injection and vaporization, saturation, permeation and diffusion techniques. The resulting gas mixtures can be monitored and measured using flame ionization, photoionization, electrochemical and infrared analytical systems. An ideal system for the production of controlled test atmospheres would not only be able to generate controlled test atmospheres, but also monitor all pertinent environmental parameters, such as temperature, humidity, and air flow.
Date: February 6, 1981
Creator: Nelson, G.O.
System: The UNT Digital Library
Pulse shaping on the Nova laser system (open access)

Pulse shaping on the Nova laser system

Inertial confinement fusion requires temporally shaped pulses to achieve high gain efficiency. Recently, we demonstrated the ability to produce complex temporal pulse shapes at high power at 0.35 microns on the Nova laser system. 2 refs., 2 figs.
Date: February 6, 1989
Creator: Lawson, J. K.; Speck, D. R.; Bibeau, C.; Weiland, T. L. & Chaffee, P. H.
System: The UNT Digital Library
Microseismic monitoring of the Chaveroo oil field, New Mexico (open access)

Microseismic monitoring of the Chaveroo oil field, New Mexico

Microseismicity was monitored in the Chaveroo oil field in southeastern New Mexico during, and for 5 weeks following, a pressurized stimulation of a well being prepared as an injector for a water flood operation. Three-thousand barrels of water were injected into the reservoir over a 5.5-hour period. Little seismicity was detected during the stimulation. Intermittent monitoring over a 5-week period following the injection indicated detectable seismicity occurring with activity levels varying in time. The most active period recorded occurred just after production resumed in the immediate area of the monitor well. Mapping the microearthquakes using the hodogram technique indicates the events occur along linear trends which corroborate known structural trends of the field. Seismicity trends were defined both parallel and perpendicular to the regionally defined maximum horizontal stress direction. Seventy-three good quality events were recorded, in a cumulative 24 hour period, from which structures were mapped up to 3000 ft from the monitor well. 13 refs., 9 figs.
Date: February 6, 1990
Creator: Rutledge, J. T. & Albright, J. N.
System: The UNT Digital Library
Capturing asteroids into bound orbits around the earth: Massive early return on an asteroid terminal defense system (open access)

Capturing asteroids into bound orbits around the earth: Massive early return on an asteroid terminal defense system

Nuclear explosives may be used to capture small asteroids (e.g., 20--50 meters in diameter) into bound orbits around the earth. The captured objects could be used for construction material for manned and unmanned activity in Earth orbit. Asteroids with small approach velocities, which are the ones most likely to have close approaches to the Earth, require the least energy for capture. They are particularly easy to capture if they pass within one Earth radius of the surface of the Earth. They could be intercepted with intercontinental missiles if the latter were retrofit with a more flexible guiding and homing capability. This asteroid capture-defense system could be implemented in a few years at low cost by using decommissioned ICMs. The economic value of even one captured asteroid is many times the initial investment. The asteroid capture system would be an essential part of the learning curve for dealing with larger asteroids that can hit the earth.
Date: February 6, 1992
Creator: Hills, J.G.
System: The UNT Digital Library
Capturing asteroids into bound orbits around the earth: Massive early return on an asteroid terminal defense system (open access)

Capturing asteroids into bound orbits around the earth: Massive early return on an asteroid terminal defense system

Nuclear explosives may be used to capture small asteroids (e.g., 20--50 meters in diameter) into bound orbits around the earth. The captured objects could be used for construction material for manned and unmanned activity in Earth orbit. Asteroids with small approach velocities, which are the ones most likely to have close approaches to the Earth, require the least energy for capture. They are particularly easy to capture if they pass within one Earth radius of the surface of the Earth. They could be intercepted with intercontinental missiles if the latter were retrofit with a more flexible guiding and homing capability. This asteroid capture-defense system could be implemented in a few years at low cost by using decommissioned ICMs. The economic value of even one captured asteroid is many times the initial investment. The asteroid capture system would be an essential part of the learning curve for dealing with larger asteroids that can hit the earth.
Date: February 6, 1992
Creator: Hills, J. G.
System: The UNT Digital Library
Effects of high beam rates on TPC's (open access)

Effects of high beam rates on TPC's

The TPC's (Time Projection Chamber) used in E-810 at the AGS (Alternating Gradient Synchroton) were exposed to silicon ion fluxes equivalent to more than 10{sup 7} minimum ionizing particles per second to measure the distortion of the electric field caused by positive ions in the drift region. Results of these tests are presented and the consequences for the TPC based experiment at RHIC (Relativistic Heavy Ion Collider) are discussed.
Date: February 6, 1992
Creator: Etkin, A.; Eiseman, S. E.; Foley, K. J.; Hackenburg, R. W.; Longacre, R. S.; Love, W. A. et al.
System: The UNT Digital Library
Development of a guidance document for lightning protection of DOE facilities (open access)

Development of a guidance document for lightning protection of DOE facilities

The purpose of this guidance document is to introduce Lighting Hazard Management, a unified approach that combines hazard identification and facility categorization (not discussed in this paper) with a new concept -- the Lighting Safety System. We do not intend to develop a brand new lightning code or standard, but rather reference other codes, standards and guides that we determine to be applicable. Using the graded approach to systematic risk management allows for in-depth protection and aids in ensuring personnel safety and optimizing resource protection.
Date: February 6, 1995
Creator: Hasbrouck, R.T. & Majumdar, K.C.
System: The UNT Digital Library
Process simulator for time-dependent material and energy flow in a continuous casting system (open access)

Process simulator for time-dependent material and energy flow in a continuous casting system

A process simulator is developed for the material and energy flow in a continuous casting system which utilizes an electron-beam energy source. A time-dependent, one-dimensional model is used which accounts for energy transport within the ingot and transport to the surroundings by conduction, thermal radiation, and the formation of secondary electrons. Also included are the mass and energy additions associated with the poured metal. A modified finite element method is used to solve the energy equation while tracking boundaries at the pool surface and solidification zone. Model parameters are determined using results from a steady-state experiment and a more detailed two-dimensional model for fluid flow and energy transport. For a transient experiment with pouring, a comparison is made between predicted and measured heat flows.
Date: February 6, 1995
Creator: Westerberg, K.W. & McClelland, M.A.
System: The UNT Digital Library
Heavy ion fusion experiments at LLNL (open access)

Heavy ion fusion experiments at LLNL

We review the status of the experimental campaign being carried out at Lawrence Livermore National Laboratory, involving scaled investigations of the acceleration and transport of space-charge dominated heavy ion beams. The ultimate goal of these experiments is to help lay the groundwork for a larger scale ion driven inertial fusion reactor, the purpose of which is to produce inexpensive and clean electric power.
Date: February 6, 1996
Creator: Barnard, J. J.; Cable, M. D. & Callahan, D. A.
System: The UNT Digital Library
Physics design and scaling of recirculating induction accelerators: from benchtop prototypes to drivers (open access)

Physics design and scaling of recirculating induction accelerators: from benchtop prototypes to drivers

Recirculating induction accelerators (recirculators) have been investigated as possible drivers for inertial fusion energy production because of their potential cost advantage over linear induction accelerators. Point designs were obtained and many of the critical physics and technology issues that would need to be addressed were detailed. A collaboration involving Lawrence Livermore National Laboratory and Lawrence Berkeley National Laboratory researchers is now developing a small prototype recirculator in order to demonstrate an understanding of nearly all of the critical beam dynamics issues that have been raised. We review the design equations for recirculators and demonstrate how, by keeping crucial dimensionless quantities constant, a small prototype recirculator was designed which will simulate the essential beam physics of a driver. We further show how important physical quantities such as the sensitivity to errors of optical elements (in both field strength and placement), insertion/extraction, vacuum requirements, and emittance growth, scale from small-prototype to driver-size accelerator.
Date: February 6, 1996
Creator: Barnard, J. J.; Cable, M. D. & Callahan, D. A.
System: The UNT Digital Library
Void growth and softening of a single crystal with strain gradient effects (open access)

Void growth and softening of a single crystal with strain gradient effects

The strain gradient crystal plasticity theory is applied to study the deformation of planar single crystal with a void under a nominally uniaxial tension. The crystal theory assumes elevated strain hardening due to slip gradients and has a constitutive length scale. The effects of the void size with respect to the constitutive length scale on the single crystal deformation are investigated.
Date: February 6, 1997
Creator: Shu, John Y.
System: The UNT Digital Library
Gauge theories with tensors from branes and orientifolds (open access)

Gauge theories with tensors from branes and orientifolds

None
Date: February 6, 1998
Creator: Csaki, Csaba; Schmaltz, Martin; Skiba, Witold & Terning, John
System: The UNT Digital Library
Indexing contamination surveys (open access)

Indexing contamination surveys

The responsibility for safely managing the Tank Farms at Hanford belongs to Lockheed Martin Hanford Corporation which is part of the six company Project Hanford Management Team led by Fluor Daniel Hanford, Inc.. These Tank Farm Facilities contain numerous outdoor contamination areas which are surveyed at a periodicity consistent with the potential radiological conditions, occupancy, and risk of changes in radiological conditions. This document describes the survey documentation and data tracking method devised to track the results of contamination surveys this process is referred to as indexing. The indexing process takes a representative data set as an indicator for the contamination status of the facility. The data are further manipulated into a single value that can be tracked and trended using standard statistical methodology. To report meaningful data, the routine contamination surveys must be performed in a manner that allows the survey method and the data collection process to be recreated. Three key criteria are necessary to accomplish this goal: Accurate maps, consistent documentation, and consistent consolidation of data meeting these criteria provides data of sufficient quality to be tracked. Tracking of survey data is accomplished by converting the individual survey results into a weighted value, corrected for the actual …
Date: February 6, 1998
Creator: Brown, R.L.
System: The UNT Digital Library
Fabrication and Test Results of a Nb3Sn Superconducting Racetrack Dipole Magnet (open access)

Fabrication and Test Results of a Nb3Sn Superconducting Racetrack Dipole Magnet

A 'proof-of-principle' Nb{sub 3}Sn superconducting dual-bore dipole magnet was built from racetrack coils, as a first step in a program to develop an economical, 15 Tesla, accelerator-quality magnet. The mechanical design and magnet fabrication procedures are discussed. No training was required to achieve temperature-dependent plateau currents, despite several thermal cycles that involved partial magnet disassembly and substantial pre-load variations. Subsequent magnets are expected to approach 15 Tesla with substantially improved conductor.
Date: February 6, 2000
Creator: Chow, K.; Dietderich, D. R.; Gourlay, S. A.; Gupta, R.; Harnden, W.; Lietzke, A. F. et al.
System: The UNT Digital Library
MSW Effects in Vacuum Oscillations (open access)

MSW Effects in Vacuum Oscillations

We point out that for solar neutrino oscillations with the mass-squared difference of Delta m^2 ~;; 10^-10 - 10^-9 eV^2, traditionally known as"vacuum oscillation'' range, the solar matter effects are non-negligible, particularly for the low energy pp neutrinos. One consequence of this is that the values of the mixing angle theta and pi/2-theta are not equivalent, leading to the need to consider the entire physical range of the mixing angle 0<=theta<=pi/2 when determining the allowed values of the neutrino oscillation parameters.
Date: February 6, 2000
Creator: Friedland, Alexander
System: The UNT Digital Library
Explosion-induced combustion of hydrocarbon clouds in a chamber (open access)

Explosion-induced combustion of hydrocarbon clouds in a chamber

The interaction of the detonation of a solid HE-charge with a non-premixed cloud of hydro-carbon fuel in a chamber was studied in laboratory experiments. Soap bubbles filled with a flammable gas were subjected to the blast wave created by the detonation of PETN-charges (0.2 g < mass < 0.5 g). The dynamics of the combustion system were investigated by means of high-speed photography and measurement of the quasi-static chamber pressure.
Date: February 6, 2001
Creator: Neuwald, P; Reichenbach, H & Kuhl, A L
System: The UNT Digital Library
Metastable metallic hydrogen glass (open access)

Metastable metallic hydrogen glass

The quest for metallic hydrogen has been going on for over one hundred years. Before hydrogen was first condensed into a liquid in 1898, it was commonly thought that condensed hydrogen would be a metal, like the monatomic alkali metals below hydrogen in the first column of the Periodic Table. Instead, condensed hydrogen turned out to be transparent, like the diatomic insulating halogens in the seventh column of the Periodic Table. Wigner and Huntington predicted in 1935 that solid hydrogen at 0 K would undergo a first-order phase transition from a diatomic to a monatomic crystallographically ordered solid at {approx}25 GPa. This first-order transition would be accompanied by an insulator-metal transition. Though searched for extensively, a first-order transition from an ordered diatomic insulator to a monatomic metal is yet to be observed at pressures up to 120 and 340 GPa using x-ray diffraction and visual inspection, respectively. On the other hand, hydrogen reaches the minimum electrical conductivity of a metal at 140 GPa, 0.6 g/cm{sup 3}, and 3000 K. These conditions were achieved using a shock wave reverberating between two stiff sapphire anvils. The shock wave was generated with a two-stage light-gas gun. This temperature exceeds the calculated melting temperature …
Date: February 6, 2001
Creator: Nellis, W J
System: The UNT Digital Library
Mixing-controlled exothermic fields in explosions (open access)

Mixing-controlled exothermic fields in explosions

A theoretical model of combustion in explosions at large Reynolds, Peclet and Damkoehler numbers is described. A key feature of the model is that combustion is treated as material transformations in the Le Chatelier state plane, rather than ''heat release''. In the limit considered here, combustion is concentrated on thin exothermic sheets (boundaries between fuel and oxidizer). The products seem to expand along the sheet, thereby inducing vorticity on either side of the sheet that continues to feed the process. The results illustrate the linking between turbulence (vorticity) and exothermicity (dilatation) in the limit of fast chemistry--thereby demonstrating the controlling role that fluid dynamics plays in such problems.
Date: February 6, 2001
Creator: Kuhl, A L; Oppenheim, A K & Ferguson, R E
System: The UNT Digital Library
Simulations of shock-induced mixing& combustion of an acetylene cloud in a chamber (open access)

Simulations of shock-induced mixing& combustion of an acetylene cloud in a chamber

In this paper we present numerical simulations of the interaction of a blast wave with an acetylene bubble in a closed chamber. We model the system using the inviscid Euler equations for a mixture of ideal gases. The formulation specifies the thermodynamic behavior of the system using a Chemkin interface and includes the capability to model combustion as the ambient air mixes with the acetylene. The simulations are performed using a three-dimensional adaptive mesh refinement algorithm based on a second-order Godunov integration scheme. Simulations are compared with experimental measurements for the same configuration.
Date: February 6, 2001
Creator: Bell, J B; Day, M S; Beckner, V E; Kuhl, A L; Neuwald, P & Reichenbach, H
System: The UNT Digital Library