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Radiation-driven evolution of low-mass x-ray binaries and the formation of millisecond pulsars

Description: Recent data on low-mass X-ray binaries (LMXBs) and millisecond pulsars (MSPs) pose a challenge to evolutionary theories which neglect the effects of disk and comparison irradiation. Here we discuss the main features of a radiation-driven (RD) evolutionary model that may be applicable to several LMXBs. According to this model, radiation from the accreting compact star in LMXBs vaporizes'' the accretion disk and the companion star by driving a self-sustained mass loss until a sudden accretion-tur… more
Date: August 8, 1991
Creator: Tavani, M. (Lawrence Livermore National Lab., CA (United States) California Univ., Berkeley, CA (United States). Dept. of Astronomy)
Partner: UNT Libraries Government Documents Department
open access

Application of telerobotic control to remote processing of nuclear material

Description: In processing radioactive material there are certain steps which have customarily required operators working at glove box enclosures. This can subject the operators to low level radiation dosages and the risk of accidental contamination, as well as generate significant radioactive waste to accommodate the human interaction. An automated system is being developed to replace the operator at the glove box and thus remove the human from these risks, and minimize waste. Although most of the processi… more
Date: July 8, 1991
Creator: Merrill, R. D.; Grasz, E. L.; Herget, C. J.; Gavel, D. T.; Addis, R. B. & DeMinico, G. A.
Partner: UNT Libraries Government Documents Department
open access

[Magazine Article: Hypocritical Oath]

Description: A copy of a newspaper article pertaining to Califonia's Proposition 186 and the reaction of the gay and lesbian community.
Date: November 8, 1994
Partner: UNT Libraries Special Collections
open access

Considerations for an active and passive scanner to assay nuclear waste drums

Description: Radioactive wastes are generated at many DOE laboratories, military facilities, fuel fabrication and enrichment plants, reactors, hospitals, and university research facilities. At all of these sites, wastes must be separated, packaged, categorized, and packed into some sort of container--usually 208-L (55-gal) drums--for shipment to waste-storage sites. Prior to shipment, the containers must be labeled, assayed, and certified; the assay value determines the ultimate disposition of the waste con… more
Date: June 8, 1990
Creator: Martz, H. E.; Azevedo, S. G.; Roberson, G. P.; Schneberk, D. J.; Koenig, Z. M. & Camp, D.C. (Lawrence Livermore National Lab., CA (USA))
Partner: UNT Libraries Government Documents Department
open access

Editing graphs for maximum effect

Description: The paper contains over eighty rules for editing graphs, arranged under nine major headings in a logical sequence for editing all the graphs in a manuscript. It is excerpted from a monograph used at the Lawrence Livermore National Laboratory to train beginning technical editors in editing graphs; a corresponding Hypercard stack is also used in this training. 6 refs., 4 figs.
Date: January 8, 1991
Creator: Murphy, P. W. & Rhiner, R. W.
Partner: UNT Libraries Government Documents Department
open access

Competing electron-electron/electron-phonon interactions and polyacetylene

Description: Using Lanczos exact diagonalization, we investigate the effects of the competition between the electro-electron and electron-phonon interactions in the context of the 1-D tight-binding Peierls-Hubbard Hamiltonian, studying various structural, optical, and vibrational properties of strongly correlated systems. We use polyacetylene as our experimental guide, and perform a parameter space search to determine the level at which a unique set of parameters can model this prototypical conducting polym… more
Date: April 8, 1991
Creator: Gammel, J.T. (Los Alamos National Lab., NM (USA) Bayreuth Univ. (Germany, F.R.). Physics Inst.); Campbell, D.K. (Los Alamos National Lab., NM (USA)) & Loh, E.Y. Jr. (Thinking Machines Corp., Cambridge, MA (USA))
Partner: UNT Libraries Government Documents Department
open access

A 3D Particle Simulation Code for Heavy Ion Fusion Accelerator Studies

Description: We describe WARP, a new particle-in-cell code being developed and optimized for ion beam studies in true geometry. We seek to model transport around bends, axial compression with strong focusing, multiple beamlet interaction, and other inherently 3d processes that affect emittance growth. Constraints imposed by memory and running time are severe. Thus, we employ only two 3d field arrays ({rho} and {phi}), and difference {phi} directly on each particle to get E, rather than interpolating E from … more
Date: June 8, 1990
Creator: Friedman, A.; Bangerter, R. O.; Callahan, D. A.; Grote, D. P.; Langdon, A. B. & Haber, I.
Partner: UNT Libraries Government Documents Department
open access

Development of deep drawn aluminum piston tanks

Description: An aluminum piston tank has been developed for applications requiring lightweight, low cost, low pressure, positive-expulsion liquid storage. The 3 liter (183 in{sup 3}) vessel is made primarily from aluminum sheet, using production forming and joining operations. The development process relied mainly on pressurizing prototype parts and assemblies to failure, as the primary source of decision making information for driving the tank design toward its optimum minimum-mass configuration. Critical … more
Date: June 8, 1990
Creator: Whitehead, J. C.; Bronder, R. L.; Kilgard, L. W.; Evans, M. C.; Ormsby, A. E.; Spears, H. R. et al.
Partner: UNT Libraries Government Documents Department
open access

The records management challenge

Description: No Description Available.
Date: August 8, 1990
Creator: Zeile, H. J.
Partner: UNT Libraries Government Documents Department
open access

Implementing the theories: A fully integrated project control system that`s implemented and works

Description: Using the theories presented in DOE Orders 4700.1, 1332.1A, and Notice 4700.5 as the basis for system design, the Fernald Environmental Restoration Management Corporation (FERMCO) has developed and implemented a Project Control System (PCS) that complies with requirements and provides DOE and FERMCO management with timely performance measurement information. To this extent, the FERMCO PCS probably is similar to the systems of the majority of the contractors in the DOE complex. In fact. this fac… more
Date: December 8, 1994
Creator: Harris, R. E.
Partner: UNT Libraries Government Documents Department
open access

Defining the role of risk assessment in the comprehensive environmental response compensation and liability act remedial investigation process at the DOE-OR

Description: Cleanup of hazardous waste sites under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) is a complicated and painstaking process, particularly at facilities with a multitude of individual hazardous waste sites, each having a multitude of chemicals and radonuclides. The US Department of Energy-Oak Ridge, Environmental Restoration Division (DOE-OR/ERD) administers five such facilities which are undergoing environmental cleanup under the CERCLA Remedial Investigat… more
Date: March 8, 1994
Creator: Miller, P. D.; McGinn, C. W.; White, R. K.; Purucker, S. T. & Redfearn, A.
Partner: UNT Libraries Government Documents Department
open access

Occupied and unoccupied orbitals of C{sub 60} and C{sub 70}

Description: The full spectrum of occupied and unoccupied {sigma} and {pi} orbitals is presented for solid C{sub 60}, C{sub 70}, and graphite, using Cls emission and absorption spectroscopy. There are significant differences between C{sub 60} and C{sub 70}, and even larger changes relative to their infinite analog graphite C{sub {infinity}}. A comparison is made with photoemission and inverse photoemission results, along with first principles quasiparticle calculations.
Date: March 8, 1994
Creator: Carlisle, J. A.; Terminello, L. J. & Hudson, E. S.
Partner: UNT Libraries Government Documents Department
open access

The superconducting solenoid magnet system for the GEM detector at the SSC

Description: The design of the magnet for the GEM detector at the SSC is described. It is an 18m inner diameter, 30m long superconducting solenoid, with a magnetic field of 0.8T. The basic solenoidal field is shaped by large ferromagnetic cones, to improve detector performance in the ends of the solenoid. Because of the system`s large size and mass, field-fabrication on-site at SSC is required. The challenges in this process, together with the large stored energy of the system, 2.5 GJ, have lead to novel de… more
Date: September 8, 1993
Creator: Deis, G.; Bowers, J. & Chargin, A.
Partner: UNT Libraries Government Documents Department
open access

Supernova explosions and hydrodynamical instabilities: From core bounce to 90 days

Description: Since the advent of SN 1987A considerable progress has been made in our understanding of supernova explosions. It is now realized that they are intrinsically multidimensional in nature due to the various hydrodynamical instabilities which take place at almost all stages of the explosion. These instabilities not only modify the observables from the supernova, but are also thought to be at the heart of the supernova mechanism itself, in a way which guarantees robust and self-regulated explosions.… more
Date: January 8, 1993
Creator: Benz, W.; Colgate, S. A. & Herant, M.
Partner: UNT Libraries Government Documents Department
open access

Tests of a New Cloud Treatment in an Atmospheric General Circulation Model

Description: In this study we present a new cloud treatment in an atmospheric climate model. The water (or ice) content of clouds is a introduced as a prognostic variable, subject to both advective and diffusive transport. In the first phase of the study, the cloud water does not affect the radiative properties of clouds. We then find differences in precipitation and cloud fields, but little effect on the overall climate. In the second phase the cloud water determines the reflectivity of the clouds. This ca… more
Date: December 8, 1993
Creator: Kristjansson, J. E.
Partner: UNT Libraries Government Documents Department
open access

Tip-tilt compensation: Resolution limits for ground-based telescopes using laser guide star adaptive optics. Revision 2

Description: The angular resolution of long-exposure images from ground-based telescopes equipped with laser guide star adaptive optics systems is fundamentally limited by the the accuracy with which the tip-tilt aberrations introduced by the atmosphere can be corrected. Assuming that a natural star is used as the tilt reference, the residual error due to tilt anisoplanatism can significantly degrade the long-exposure resolution even if the tilt reference star is separated from the object being imaged by a … more
Date: October 8, 1992
Creator: Olivier, S. S.; Max, C. E.; Gavel, D. T. & Brase, J. M.
Partner: UNT Libraries Government Documents Department
open access

Realizing parallel reduction operation in Sisal 1.2. Revision 1

Description: Often the tasks of a parallel job compute sets of values that are reduced to a single value or gathered to build an aggregate structure. Since reductions may introduce dependencies, most languages separate computation and reduction. For example, Fortran 90 and HPF provide a rich set of predefined reduction functions but only for extant arrays. Sisal 1.2 is unique in that it supports seven reduction operations as a natural consequence of loop expressions. These reductions are limited and cannot … more
Date: August 8, 1994
Creator: Denton, S. M.; Feo, J. T. & Miller, P. J.
Partner: UNT Libraries Government Documents Department
open access

Demonstration of zinc/air fuel battery to enhance the range and mission of fleet electric vehicles: Preliminary results in the refueling of a multicell module

Description: We report progress in an effort to develop and demonstrate a refuelable zinc/air battery for fleet electric vehicle applications. A refuelable module consisting of twelve bipolar cells with internal flow system has been refueled at rates of nearly 4 cells per minute refueling time of 10 minutes for a 15 kW, 55 kWh battery. The module is refueled by entrainment of 0.5-mm particles in rapidly flowing electrolyte, which delivers the particles into hoppers above each cell in a parallel-flow hydraul… more
Date: August 8, 1994
Creator: Cooper, J. F.; Fleming, D.; Keene, L.; Maimoni, A.; Peterman, K. & Koopman, R.
Partner: UNT Libraries Government Documents Department
open access

High field solenoids for muon cooling

Description: The proposed cooling system for the muon collider will consist of a 200 meter long line of alternating field straight solenoids interspersed with bent solenoids. The muons are cooled in all directions using a 400 mm long section liquid hydrogen at high field. The muons are accelerated in the forward direction by about 900 mm long, 805 MHz RF cavities in a gradient field that goes from 6 T to -6 T in about 300 mm. The high field section in the channel starts out at an induction of about 2 T in t… more
Date: September 8, 1999
Creator: Green, M. A.; Eyssa, Y.; Kenny, S.; Miller, J. R. & Prestemon, S.
Partner: UNT Libraries Government Documents Department
open access

RHIC IR Quadrupoles and Field Quality State of the Art in Super Conducting Accelerator Magnets

Description: The interaction region (IR) quadrupoles [1] for the Relativistic Heavy Ion Collider (RHIC)[2]are the best field quality superconducting magnets ever built for any major accelerator. This field quality is primarily achieved with the help of eight tuning shims [3] that remove the residual errors from a magnet after it is built and tested. These shims overcome the limitations from the typical tolerances in parts and manufacturing. This paper describes the tuning shims and discusses the evolution o… more
Date: March 8, 1999
Creator: Gupta, R.; Anerella, M.; Cozzolino, J.; Ghosh, A.; Jain, A.; Kahn, S. et al.
Partner: UNT Libraries Government Documents Department
open access

Recent studies of short-range order in alloys: The Cowley theory revisited

Description: We present comparisons of various statistical theories for effective pair interactions (EPI) in alloys. We then evaluate these EPI`s using the Cowley theory, the Krivoglaz-Clapp-Moss (KCM) approximation, the {gamma}-expansion method (GEM) of Tokar, Masanskii and coworkers, and the exact inverse Monte Carlo (IMC) method, introduced by Gerold and Kern. Via a series of model calculations on a hypothetical bcc alloy with a single nearest-neighbor interaction we show that the Cowley theory is succes… more
Date: February 8, 1993
Creator: Reinhard, L. & Moss, S. C.
Partner: UNT Libraries Government Documents Department
open access

An MPI implementation of the SPAI preconditioner on the T3E

Description: The authors describe and test spai_1.1, a parallel MPIimplementation of the sparse approximate inverse (SPAI) preconditioner.They show that SPAI can be very effective for solving a set of very largeand difficult problems on a Cray T3E. The results clearly show the valueof SPAI (and approximate inverse methods in general) as the viablealternative to ILU-type methods when facing very large and difficultproblems. The authorsstrengthen this conclusion by showing that spai_1.1also has very good scal… more
Date: September 8, 1997
Creator: Barnard, Stephen T.; Bernardo, Luis M. & Simon, Horst D.
Partner: UNT Libraries Government Documents Department
open access

Rare K Decays.

Description: In the rush to explore the B system, one should not ignore the potential of rare K decays. The charged and neutral FCNC K {yields} {pi}{nu}{bar {mu}} decays are theoretically very clean, on a par with B {yields} {psi}K{sub S}, which measures {beta}, and much less problematic than B {yields} {pi}{pi} and B{sub s} {yields} K{sup +}K{sup -} or B{sub s} {yields} K*{sup +}K*{sup -} which have been proposed to measure {alpha} and {gamma} respectively. B(K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}}), w… more
Date: July 8, 1997
Creator: Littenberg, L.
Partner: UNT Libraries Government Documents Department
open access

Installation of line replaceable units into the National Ignition Facility

Description: In the National Ignition Facility (NIF), currently under design and construction at Lawrence Livermore National Laboratory (LLNL), 192 high-power laser beamlines incorporating over 8,000 large optics, are focused onto a target smaller than a dime. The actual laser path will be contained within the Laser Target Area Building (LTAB), but the smaller adjacent building, the Optics Assembly Building, is where the optic modules are assembled and aligned. After the optics are finished in the OAB they … more
Date: March 8, 1999
Creator: Bahowick, S; Mcmahon, D; Rowe, A; Tiszauer, D & Yakuma, S
Partner: UNT Libraries Government Documents Department
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