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Application of the FORSS sensitivity code system to fast reactor analysis (open access)

Application of the FORSS sensitivity code system to fast reactor analysis

The FORSS Sensitivity Analysis Code System is described in terms of its objectives and present capabilities. An example is made of a problem specified by the Processing Methods Testing Subcommittee of the Code Evaluation Working Group, i.e., the determination of integral parameters, sensitivities to cross- section data, methods and data uncertainties, and required cross-section accuracies for an infinite media of ZPR 6/7 core composition. (auth)
Date: October 22, 1975
Creator: Weisbin, C. R.; Oblow, E. M. & Mynatt, F. R.
System: The UNT Digital Library
Helium generation in copper by 14.8-MeV neutrons (open access)

Helium generation in copper by 14.8-MeV neutrons

High purity copper foils were irradiated with 14.8-MeV neutrons from the rotating target neutron source facility at LLL. The average energy of the neutrons was 14.75 +- 0.1 MeV, and the average fluence was 7.0 x 10$sup 16$ n/ cm$sup 2$. After irradiation each foil was heated to the melting point and the released helium was measured by a mass spectrometer of special design. Isochronal heating was carried out on several samples to establish the type and temperature of maximum release. Calculated cross sections from the literature for the (eta,$alpha$) and (eta,eta'$alpha$) nuclear reactions were used, and the predicted amount of helium was consistently about 0.5 of that actually measured. Because there is very little data on helium generation in metals irradiated with high energy neutrons, these results are important and will be related to potential CTR materials. (auth)
Date: September 22, 1975
Creator: Holt, J.B.; Hosmer, D.W. & Van Konynenburg, R.A.
System: The UNT Digital Library
Electromagnetic pulse source characteristics experiment on an underground nuclear event (open access)

Electromagnetic pulse source characteristics experiment on an underground nuclear event

From EMP technical meeting; Kirtland AFB, New Mexico, USA (25 Sep 1973). Under sponsorship of the Advanced Research Projects Agency, the Lawrence Livermore Laboratory conducted an EMP experiment in conjunction with an underground nuclear event. The purpose of the overall study of which this experiment was a part was to document the characteristics of EMP signals generated by various underground nuclear events to provide checks for theoretical models under development. A major goal was to establish how a specific event configuration affects the signals generated. For this experiment, two separate EMP source mechanisms were considered: that due to an asymmetric gamma ray distribution resulting from shielding and configuration constraints in the vicinity of the device and that due to current induced on the line-of-sight pipe. The instrumentation was not ideally located to sort out the two mechanisms because of significant differences between the planned and as-fired configuration. Nevertheless, signals characteristic of the two mechanisms seem to be apparent in the data. An impulsive (10 MHz) component of the signal is probably a result of the asymmetric gamma distribution. A ringing component (1 MHz) has been attributed to currents on the line-of- sight pipe. (auth)
Date: October 22, 1973
Creator: Knapp, M. W. & Bailey, N. D.
System: The UNT Digital Library
Modularized mirror fusion reactor concept with emphasis on fabricability, assembly, and disassembly (open access)

Modularized mirror fusion reactor concept with emphasis on fabricability, assembly, and disassembly

None
Date: October 22, 1974
Creator: Peterson, M.A.; Werner, R.W.; Hoffman, M.A. & Carlson, G.A.
System: The UNT Digital Library
Neutron logging in partially saturated media (open access)

Neutron logging in partially saturated media

None
Date: April 22, 1974
Creator: Hearst, J. R.
System: The UNT Digital Library
Helium release from various metals (open access)

Helium release from various metals

None
Date: July 22, 1974
Creator: Cost, J. R. & Hickman, R. G.
System: The UNT Digital Library
Fusion reactor first-wall cooling for very high energy fluxes (open access)

Fusion reactor first-wall cooling for very high energy fluxes

None
Date: October 22, 1974
Creator: Hoffman, M. A.; Werner, R. W.; Roose, T. R. & Carlson, G. A.
System: The UNT Digital Library
Influence of the surface boundary layer on evolutionary models of Jupiter (open access)

Influence of the surface boundary layer on evolutionary models of Jupiter

None
Date: August 22, 1973
Creator: unknown
System: The UNT Digital Library
Future trends in computer hardware (open access)

Future trends in computer hardware

None
Date: May 22, 1973
Creator: Feustel, E.A.; Jensen, C.A. & McMahon, F.H.
System: The UNT Digital Library
Palladium--$sup 252$Cf oxide cermet, an improved form for $sup 252$Cf neutron sources (open access)

Palladium--$sup 252$Cf oxide cermet, an improved form for $sup 252$Cf neutron sources

None
Date: June 22, 1972
Creator: Mosley, W. C.; Smith, P. K. & McBeath, P. E.
System: The UNT Digital Library
Effects of a hypothetical loss-of-coolant accident on a Mark I Boiling Water Reactor pressure-suppression system (open access)

Effects of a hypothetical loss-of-coolant accident on a Mark I Boiling Water Reactor pressure-suppression system

A loss-of-coolant accident (LOCA) in a boiling-water-reactor (BWR) power plant has never occurred. However, because this type of accident could be particularly severe, it is used as a principal theoretical basis for design. A series of consistent, versatile, and accurate air-water tests that simulate LOCA conditions has been completed on a /sup 1///sub 5/-scale Mark I BWR pressure-suppression system. Results from these tests are used to quantify the vertical-loading function and to study the associated fluid dynamics phenomena. Detailed histories of vertical loads on the wetwell are shown. In particular, variation of hydrodynamic-generated vertical loads with changes in drywell-pressurization rate, downcomer submergence, and the vent-line loss coefficient are established. Initial drywell overpressure, which partially preclears the downcomers of water, substantially reduces the peak vertical loads. Scaling relationships, developed from dimensional analysis and verified by bench-top experiments, allow the /sup 1///sub 5/-scale results to be applied to a full-scale BWR power plant. This analysis leads to dimensionless groupings that are invariant. These groupings show that, if water is used as the working fluid, the magnitude of the forces in a scaled facility is reduced by the cube of the scale factor and occurs in a time reduced by the square root …
Date: December 22, 1977
Creator: Pitts, J.H. & McCauley, E.W.
System: The UNT Digital Library
Prompt leptons and hadronic jets from W mesons. [SU(2) x U(1) quark model] (open access)

Prompt leptons and hadronic jets from W mesons. [SU(2) x U(1) quark model]

The signal/background ratio for the decay of the W into hadronic jets, it is affirmed, should be improved by a factor of about 15 if a prompt lepton is required. For definiteness the hadronic decays of the W/sup +/ in an SU(2) x U(1) model with six quarks is considered. (JFP)
Date: August 22, 1977
Creator: Paige, F. E. & Palmer, R. B.
System: The UNT Digital Library
Review of issues relevant to acceptable risk criteria for nuclear waste management (open access)

Review of issues relevant to acceptable risk criteria for nuclear waste management

Development of acceptable risk criteria for nuclear waste management requires the translation of publicly determined goals and objectives into definitive issues which, in turn, require resolution. Since these issues are largely of a subjective nature, they cannot be resolved by technological methods. Development of acceptable risk criteria might best be accomplished by application of a systematic methodology for the optimal implementation of subjective values. Multi-attribute decision analysis is well suited for this purpose.
Date: February 22, 1978
Creator: Cohen, J.J.
System: The UNT Digital Library
Scaling of exploding pusher targets (open access)

Scaling of exploding pusher targets

A theory of exploding pusher laser pusher targets is compared to results of LASNEX calculations and to Livermore experiments. A scaling relationship is described which predicts the optimum target/pulse combinations as a function of the laser power.
Date: August 22, 1977
Creator: Nuckolls, J.H.
System: The UNT Digital Library
Stability of space-charge neutralized beams (open access)

Stability of space-charge neutralized beams

Consideration is given to the stability of negative ion beams which are neutralized through ionization of a background gas. Two types of instabilities are examined. First, beam-plasma instabilities are analyzed with the dispersion relation showing that they are unimportant if the beam velocity is less than the electron thermal velocity. Second, results of a computer simulation on the flow of a cylindrical beam and the resulting background plasma show that when the background neutral gas density is less than or approximately equal to a critical density as instability occurs. This critical density is the density that would be needed to space-charge neutralize the beam if the positive ions were not retarded by the beam. An approximate dispersion relation indicates that the nature of the instability is a transverse positive-ion acoustic wave which couples to the beam.
Date: September 22, 1977
Creator: Turnbull, R. J. & Hooper, E. B. Jr.
System: The UNT Digital Library
Cold-pressure-welded joints in large multifilamentary Nb--Ti superconductors (open access)

Cold-pressure-welded joints in large multifilamentary Nb--Ti superconductors

A number of mechanical and electrical measurements were made on joints in typical conductors for the proposed mirror fusion test facility (MFTF) and high field test facility (HFTF). For such measurements, a commercially available cold-pressure-welding machine was used. For joints in the MFTF conductor, which has a large proportion of superconductor, joint strength approached conductor strength. For the HFTF conductor, where the Cu-to-superconductor ratio is 4.33/1, the joint is stronger than the conductor. Electrically, the joints were not superconducting.. While the resistance is higher than might be achieved by other forms of joining, we feel that the cold-weld joint has the advantages of simplicity, speed, reliability, and reproducibility. This makes the method attractive for MFTF, where resistance losses will be small compared with the total 4 K refrigeration requirements.
Date: September 22, 1977
Creator: Cornish, D.N.; Deis, D.W. & Zbasnik, J.P.
System: The UNT Digital Library
Transport of intense particle beams with application to heavy ion fusion (open access)

Transport of intense particle beams with application to heavy ion fusion

An attractive feature of the high energy (> GeV) heavy ion beam approach to inertial fusion, as compared with other particle beam systems, is the relative simplicity involved in the transport and focusing of energy on the target inside a reactor chamber. While this focusing could be done in vacuum by conventional methods with multiple beams, there are significant advantages in reactor design if one can operate at gas pressures around one torr. In this paper we summarize the results of our studies of heavy ion beam transport in gases. With good enough charge and current neutralization, one could get a ballistically-converging beam envelope down to a few millimeters over a 10 meter path inside the chamber. Problems of beam filamentation place important restrictions on this approach. We also discuss transport in a self-focused mode, where a relatively stable pressure window is predicted similar to the observed window for electron beam transport.
Date: June 22, 1979
Creator: Buchanan, H. L.; Chambers, F. W.; Lee, E. P.; Yu, S. S.; Briggs, R. J. & Rosenbluth, M. N.
System: The UNT Digital Library
Subsystem response determination for the US NRC Seismic Safety Margins Research Program (open access)

Subsystem response determination for the US NRC Seismic Safety Margins Research Program

The initial portion of the task described deals with a definition of the state-of-the-art of seismic qualification methods for subsystems. Too facilitate treatment of this broad class of subsystems, three classifications have been identified: multiply supported subsystems (e.g., piping systems); mechanical components (e.g., valves, pumps, control rod drives, hydraulic systems, etc.); and electrical components (e.g., electrical control panels). Descriptions of the available analysis and/or testing techniques for the above classifications are sought. The results of this assessment will be applied to the development of structural subsystem transfer functions.
Date: February 22, 1979
Creator: Johnson, J. J.
System: The UNT Digital Library
Multidisciplinary training program to create new breed of radiation monitor: the health and safety technician (open access)

Multidisciplinary training program to create new breed of radiation monitor: the health and safety technician

A multidiscipline training program established to create a new monitor, theHealth and Safety Technician, is described. The training program includes instruction in fire safety, explosives safety, industrial hygiene, industrial safety, health physics, and general safety practices.
Date: October 22, 1979
Creator: Vance, W.F.
System: The UNT Digital Library
LIEPROC: a MACSYMA program for finding adiabatic invariants of simple Hamiltonian systems via the Lie transform. [In LISP for Decsystem-10] (open access)

LIEPROC: a MACSYMA program for finding adiabatic invariants of simple Hamiltonian systems via the Lie transform. [In LISP for Decsystem-10]

The usage and performance of a program in a symbolic manipulation language that computes adiabatic invariants of certain Hamiltonian systems via the Lie transform are discussed. 1 table.
Date: November 22, 1978
Creator: Char, B. & McNamara, B.
System: The UNT Digital Library
Status of the LLL tandem-shaped charge designs (open access)

Status of the LLL tandem-shaped charge designs

Lawrence Livermore Laboratory has been engaged in the design of tandem or multistage shaped charges for several years. Analytical and experimental work that focuses on how several aspects of tandem designs affect the jet characteristics is described. The work demonstrates the effectiveness of analytical methodology to specify liner geometries to achieve jets with controlled velocity gradients and high overall efficiency. It also shows that jet clippers and other ancillary components, along with controlled liner thickness, help make clean breaks between the jet and the slug and facilitate insertion of a second jet. Second-stage initiation and interjet time delays are discussed.
Date: February 22, 1979
Creator: Godfrey, C.S. & Jandrisevits, R.A.
System: The UNT Digital Library
Effect of transport in distribution of radioions and radiolabeled metabolites (open access)

Effect of transport in distribution of radioions and radiolabeled metabolites

The following topics are discussed: route of administration; carrier effects and complexed or ionic tracers; membrane permeability, extracellular and intracellular concentrations; enzyme and hormonal stimulation or depression and the metabolic state; neoplasia and transport; and carrier for radiopharmaceutical binding to membrane or protein sites. Some radioisotopes considered are /sup 99m/Tc, /sup 65/Zn, /sup 62/Zn, /sup 14/C and /sup 111/In. (HLW)
Date: December 22, 1977
Creator: Yano, Y.
System: The UNT Digital Library
Quality assurance in environmental monitoring at the Lawrence Livermore Laboratory (open access)

Quality assurance in environmental monitoring at the Lawrence Livermore Laboratory

The quality assurance program for environmental monitoring that has been developed at the Lawrence Livermore Laboratory (LLL) consists of procedure documentation, replicate field-sample analysis, and participation in intercomparison measurements. Sampling, analytical, data processing, and record keeping procedures are described. A replicate-sample collection schedule has been established for all media sampled at LLL. At present, blind-spiked samples are not utilized. Flow rates of air samplers are verified at monthly intervals using a portable, field calibration unit. Intercomparison measurements are made on samples supplied by the Quality Assurance Branch of the Environmental Protection Agency-Environmental Monitoring and Support Laboratory and the Department of Energy-Environmental Measurements Laboratory. Replicate sampling currently accounts for approximately 8% of both the total samples collected and the analyses performed. Including standard, in-house, quality-control checks, and the intercomparison measurements, it is estimated that during 1978 quality assurance will represent about 15% of the total environmental-monitoring effort at LLL.
Date: May 22, 1978
Creator: Lindeken, C. L.; White, J. H. & Silver, W. J.
System: The UNT Digital Library
Optical components for the SHIVA laser (open access)

Optical components for the SHIVA laser

SHIVA, the 10-kilojule Neodymium-glass laser for the High Energy Laser Facility at Lawrence Livermore Laboratory has been built, exceeded minimum energy predictions, and is currently being applied to laser fusion experiments. The twenty, 20-cm aperture arms contain a total of about 1500 optical components for beam propagation, and another 1000 elements are used for control systems and diagnostics. In order to focus the energy on targets smaller than 1 mm in diameter, it has been necessary to maintain very high optical quality throughout the system. The manufacturing and testing technologies involved in meeting this challenge have been noteworthy and have encompassed glass manufacturing, optical finishing, and coating, for elements as diverse as Faraday rotators, laser rods and disks and aspheric lenses.
Date: December 22, 1977
Creator: Wallerstein, E. P.; Marchi, F. T.; Whistler, W. T. & Bissinger, H. D.
System: The UNT Digital Library