Measurement of energy deposited by charged-particle beams in composite targets (open access)

Measurement of energy deposited by charged-particle beams in composite targets

We have measured the energy deposited in two types of composite targets by a number of charged-particle beams: targets made of /sup 238/U, Lucite, and polyethylene were exposed to 0.26-GeV protons and 0.33-GeV deuterons, and aluminum-Lucite composites were exposed to 0.5-GeV electrons. In addition, we measured neutrons and gamma rays emitted from solid targets of various materials (including /sup 238/U and iron) exposed to 0.26-GeV protons and 0.33-GeV deuterons. We used passive detectors (thermoluminescence dosimeters, Lexan fission track recorders, and photographic emulsions) to measure the nonfission dose and the fission-fragment dose from the primary beam and its shower of products. Measurements were made at various depths and radial positions in the targets. Plots and numerical values of the measured doses are presented. The emission of neutrons and gamma rays was measured with a liquid-deuterated-benzene detector. In general, the dose profile with depth is similar for 0.26-GeV protons and 0.33-GeV deuterons. The ratio of return neutrons to gamma rays increases with increasing target mass number. Deuterons, however, produce from 1.7 to 5.8 times as many neutrons and gamma rays per particle as do protons.
Date: July 2, 1980
Creator: Farley, E.; Becker, J.; Crase, K.; Howe, R. & Selway, D.
Object Type: Report
System: The UNT Digital Library
Analysis of oxygen on and in beryllium using 2 MeV helium ions (open access)

Analysis of oxygen on and in beryllium using 2 MeV helium ions

Analysis of oxygen on beryllium can be routinely performed using helium-ion backscattering (RBS). However, determination of the bulk oxygen concentration by this technique is limited to about 350 atomic parts per million (appM). We have performed simultaneous RBS and particle-induced x-ray emission (PIXE) measurements to improve the detection limit for bulk oxygen. The RBS measurements allowed determination of the surface oxygen before and after in-situ sputter cleaning by argon ions in an ultra-high-vacuum system. PIXE measurements of specimens with surfaces maintained clean by sputtering permitted assessment of the concentration of oxygen in the bulk. For our geometry and detector sensitivities, 90% of the oxygen x-ray signal originated in the first 2.1 ..mu..m of the beryllium and a detection limit of 10 appM was found. 12 refs., 3 figs.
Date: October 2, 1986
Creator: Musket, R.G.
Object Type: Article
System: The UNT Digital Library
Piqua Nuclear Power Facility Radiological Surveillance Program (open access)

Piqua Nuclear Power Facility Radiological Surveillance Program

Results of the annual radiological survey of the retired Piqua Nuclear Facility in Piqua, Ohio are presented in this report. The overall survey did not reveal the existence of any significant changes within the facility. This survey marked the inception of a surface soil sampling program. Analysis of the soil revealed that concentrations of radioactivity are comparable to those found at other locations in Ohio. (DMC)
Date: March 2, 1982
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Enhanced durability and reactivity for zinc ferrite desulfurization sorbent (open access)

Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.
Date: May 2, 1989
Creator: Jha, M. C. & Berggren, M. H.
Object Type: Report
System: The UNT Digital Library
Enhanced Durability and Reactivity for Zinc Ferrite Desulfurization Sorbent (open access)

Enhanced Durability and Reactivity for Zinc Ferrite Desulfurization Sorbent

AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.
Date: May 2, 1989
Creator: Silaban, A. & Harrison, D.P.
Object Type: Report
System: The UNT Digital Library
Recovery and reuse of asphalt roofing waste. Final report (open access)

Recovery and reuse of asphalt roofing waste. Final report

Burning of asphalt roofing waste as a fuel and incorporating asphalt roofing waste in bituminous paving were identified as the two outstanding resource recovery concepts out of ten studied. Four additional concepts might be worth considering under different market or technical circumstances. Another four concepts were rated as worth no further consideration at this time. This study of the recovery of the resource represented in asphalt roofing waste has identified the sources and quantities of roofing waste. About six million cubic yards of scrap roofing are generated annually in the United States, about 94% from removal of old roofing at the job site and the remainder from roofing material production at factories. Waste disposal is a growing problem for manufacturers and contractors. Nearly all roofing waste is hauled to landfills at a considerable expense to roofing contractors and manufacturers. Recovery of the roofing waste resource should require only a modest economic incentive. The asphalt contained in roofing waste represents an energy resource of more than 7 x 10/sup 13/ Btu/year. Another 1 x 10/sup 13/ Btu/year may be contained in field-applied asphalt on commercial building roofs. The two concepts recommended by this study appear to offer the broadest applicability, the …
Date: February 2, 1984
Creator: Desai, S.; Graziano, G. & Shepherd, P.
Object Type: Report
System: The UNT Digital Library
Fusion power demonstration - a baseline for the mirror engineering test reactor (open access)

Fusion power demonstration - a baseline for the mirror engineering test reactor

Developing a definition of an engineering test reactor (ETR) is a current goal of the Office of Fusion Energy (OFE). As a baseline for the mirror ETR, the Fusion Power Demonstration (FPD) concept has been pursued at Lawrence Livermore National Laboratory (LLNL) in cooperation with Grumman Aerospace, TRW, and the Idaho National Engineering Laboratory. Envisioned as an intermediate step to fusion power applications, the FPD would achieve DT ignition in the central cell, after which blankets and power conversion would be added to produce net power. To achieve ignition, a minimum central cell length of 67.5 m is needed to supply the ion and alpha particles radial drift pumping losses in the transition region. The resulting fusion power is 360 MW. Low electron-cyclotron heating power of 12 MW, ion-cyclotron heating of 2.5 MW, and a sloshing ion beam power of 1.0 MW result in a net plasma Q of 22. A primary technological challenge is the 24-T, 45-cm bore choke coil, comprising a copper hybrid insert within a 15 to 18 T superconducting coil.
Date: December 2, 1983
Creator: Henning, C. D.; Logan, B. G.; Neef, W. S.; Dorn, D.; Clarkson, I. R.; Carpenter, T. et al.
Object Type: Article
System: The UNT Digital Library
Transducer characterization (open access)

Transducer characterization

This report has been prepared specifically for ultrasonic transducer users within the Nondestructive Testing Evaluation (NDE) community of the weapons complex. The purpose of the report is to establish an initial set of uniform procedures for measuring and recording transducer performance data, and to establish a common foundation on which more comprehensive transducer performance evaluations may be added as future transducer performance criteria expands. Transducer parameters and the problems with measuring them are discussed and procedures for measuring transducer performance are recommended with special precautionary notes regarding critical aspects of each measurement. An important consideration regarding the recommended procedures is the cost of implementation. There are two distinct needs for transducer performance characterization in the complex. Production oriented users need a quick, reliable means to check a transducer to ascertain its suitability for continued service. Development groups and the Transducer Center need a comprehensive characterization means to collect adequate data to evaluate theoretical concepts or to build exact replacement transducers. The instrumentation, equipment, and procedures recommended for monitoring production transducers are utilitarian and provide only that information needed to determine transducer condition.
Date: July 2, 1980
Creator: Cross, B. T.; Eoff, J. M.; Schuetz, L. J. & Cunningham, K. R.
Object Type: Report
System: The UNT Digital Library
Radiation-induced electrical breakdown of helium in fusion reactor superconducting magnet systems (open access)

Radiation-induced electrical breakdown of helium in fusion reactor superconducting magnet systems

A comprehensive theoretical study has been performed on the reduction of the electrical breakdown potential of liquid and gaseous helium under neutron and gamma radiation. Extension of the conventional Townsend breakdown theory indicates that radiation fields at the superconducting magnets of a typical fusion reactor are potentially capable of significantly reducing currently established (i.e., unirradiated) helium breakdown voltages. Emphasis is given to the implications of these results including future deployment choices of magnet cryogenic methods (e.g., pool-boiling versus forced-flow), the possible impact on magnet shielding requirements and the analogous situation for radiation-induced electrical breakdown in fusion RF transmission systems.
Date: December 2, 1983
Creator: Perkins, L.J.
Object Type: Article
System: The UNT Digital Library
Calculation of density profiles in tandem mirrors fueled by pellets (open access)

Calculation of density profiles in tandem mirrors fueled by pellets

We have modified the LLNL radial transport code TMT to model reactor regime plasmas, fueled by pellets. The source profiles arising from pellet fueling are obtained from existing pellet ablation models. Because inward radial diffusion due to inverted profiles must compete with trapping of central cell ions in the transition region for tandem mirrors, pellets must penetrate fairly far into the plasma. In fact, based on our radial calculations, a pellet with a velocity of 10 km/sec cannot sustain the central flux tubes; a velocity more like 100 km/sec will be necessary. We also find that the central cell radial diffusion must exceed classical by about a factor of 100.
Date: December 2, 1983
Creator: Campbell, R. B. & Gilmore, J. M.
Object Type: Article
System: The UNT Digital Library
Milliwatt generator heat source. Progress report, July-December 1983 (open access)

Milliwatt generator heat source. Progress report, July-December 1983

All LANL hardware requirements were met during the reporting period as scheduled. Lot 12 of T-111 alloy sheet and Lot 8 of yttrium platelets were procured to meet future WR production needs. The GEND IP schedule requirements for 49 fueled MC2893 heat sources were met. Pressure burst surveillance activities continued to be conducted in accordance with SNLA document BB328965. Final results of evaluations of two pressure-burst capsules were normal, suggesting that the corresponding heat sources should be in good condition. The hardware production period ended with an overall hardware process yield of 98.4%.
Date: March 2, 1984
Creator: Mershad, E.A.
Object Type: Report
System: The UNT Digital Library
Seismic Safety Margins Research Program: Phase II program plan (FY 83-FY 84) (open access)

Seismic Safety Margins Research Program: Phase II program plan (FY 83-FY 84)

The Seismic Safety Margins Research Program (SSMRP) is an NRC-funded, multiyear program conducted by Lawrence Livermore National Laboratory (LLNL). Its goal is to develop a complete, fully coupled analysis procedure (including methods and computer codes) for estimating the risk of an earthquake-caused radioactive release from a commercial nuclear power plant. The analysis procedure is based upon a state-of-the-art evaluation of the current seismic analysis and design process and explicitly includes the uncertainties inherent in such a process. The results will be used to improve seismic licensing requirements for nuclear power plants. As currently planned, the SSMRP will be completed in September, 1984. This document presents the program plan for work to be done during the remainder of the program. In Phase I of the SSMRP, the necessary tools (both computer codes and data bases) for performing a detailed seismic risk analysis were identified and developed. Demonstration calculations were performed on the Zion Nuclear Power Plant. In the remainder of the program (Phase II) work will be concentrated on developing a simplified SSMRP methodology for routine probabilistic risk assessments, quantitative validation of the tools developed and application of the simplified methodology to a Boiling Water Reactor. (The Zion plant is a …
Date: August 2, 1982
Creator: Bohn, M. P.; Bernreuter, D. L.; Cover, L. E.; Johnson, J. J.; Shieh, L. C.; Shukla, S. N. et al.
Object Type: Report
System: The UNT Digital Library
Recent results of studies of acceleration of compact toroids (open access)

Recent results of studies of acceleration of compact toroids

The observed gross stability and self-contained structure of compact toroids (CT's) give rise to the possibility, unique among magnetically confined plasmas, of translating CT's from their point of origin over distances many times their own length. This feature has led us to consider magnetic acceleration of CT's to directed kinetic energies much greater than their stored magnetic and thermal energies. A CT accelerator falls in the very broad gap between traditional particle accelerators at one extreme, which are limited in the number of particles per bunch by electrostatic repulsive forces, and mass accelerators such as rail guns at the other extreme, which accelerate many particles but are forced by the stress limitations of solids to far smaller accelerations. A typical CT has about a Coulomb of particles, weighs 10 micrograms and can be accelerated by magnetic forces of several tons, leading to an acceleration on the order of 10/sup 11/ gravities.
Date: March 2, 1984
Creator: Hammer, J. H.; Hartman, C. W. & Eddleman, J.
Object Type: Article
System: The UNT Digital Library
High-power pulsed lasers (open access)

High-power pulsed lasers

The ideas that led to the successful construction and operation of large multibeam fusion lasers at the Lawrence Livermore Laboratory are reviewed. These lasers are based on the use of Nd:glass laser materials. However, most of the concepts are applicable to any laser being designed for fusion experimentation. This report is a summary of lectures given by the author at the 20th Scottish University Summer School in Physics, on Laser Plasma Interaction. This report includes basic concepts of the laser plasma system, a discussion of lasers that are useful for short-pulse, high-power operation, laser design constraints, optical diagnostics, and system organization.
Date: April 2, 1980
Creator: Holzrichter, J.F.
Object Type: Report
System: The UNT Digital Library
Dissociative recombination of interstellar ions: electronic structure calculations for HCO/sup +/ (open access)

Dissociative recombination of interstellar ions: electronic structure calculations for HCO/sup +/

The present study of the interstellar formyl ion HCO/sup +/ is the first attempt to investigate dissociative recombination for a triatomic molecular ion using an entirely theoretical approach. We describe a number of fairly extensive electronic structure calculations that were performed to determine the reaction mechanism of the e-HCO/sup +/ process. Similar calculations for the isoelectronic ions HOC/sup +/ and HN/sub 2//sup +/ are in progress. 60 refs.
Date: July 2, 1985
Creator: Kraemer, W.P. & Hazi, A.U.
Object Type: Article
System: The UNT Digital Library
Recent upgrading of the modelling program COMFORT (open access)

Recent upgrading of the modelling program COMFORT

The computer code COMFORT, developed for the online control of machine functions at the SLC, has recently undergone several modifications to overcome some of its limitations. This note describes the reasons for these changes, the methods employed, some test results and the applications of the new version of the program.
Date: September 2, 1986
Creator: Hawkes, C. & Lee, M.
Object Type: Report
System: The UNT Digital Library
Thermal Regimes of Major Volcanic Centers: Magnetotelluric Constraints (open access)

Thermal Regimes of Major Volcanic Centers: Magnetotelluric Constraints

The interpretation of geophysical/electromagnetic field data has been used to study dynamical processes in the crust beneath three of the major tectono-volcanic features in North America: the Long Valley/Mono Craters Volcanic Complex in eastern California, the Cascades Volcanic Belt in Oregon, and the Rio Grande Rift in the area of Socorro, New Mexico. Primary accomplishments have been in the area of creating and implementing a variety of 2-D generalized inverse computer codes, and the application of these codes to fields studies on the basin structures and he deep thermal regimes of the above areas. In order to more fully explore the space of allowable models (i.e. those inverse solutions that fit the data equally well), several distinctly different approaches to the 2-D inverse problem have been developed: (1) an overdetermined block inversion; (2) an overdetermined spline inverstion; (3) a generalized underdetermined total inverse which allows one to tradeoff certain attributes of their model, such as minimum structure (flat models), roughness (smooth models), or length (small models). Moreover, we are exploring various approaches for evaluating the resolution model parameters for the above algorithms. 33 refs.
Date: October 2, 1989
Creator: Hermance, J. F.
Object Type: Report
System: The UNT Digital Library
Solution of the Field Equations for 2-D Electromagnetic Direct Implicit Plasma Simulation (open access)

Solution of the Field Equations for 2-D Electromagnetic Direct Implicit Plasma Simulation

A direct implicit particle-in-cell (PIC) simulation model with full electromagnetic (EM) effects has been implemented in 2-D Cartesian geometry. The model, implemented with the D/sub 1/ time differencing scheme, was first implemented in a 1-D electrostatic (ES) version to gain some experience with spatial differencing in forms suitable for extension to the full EM field in two dimensions. The implicit EM field solve is considerably different from the implicit ES code. The EM field calculation requires an inductive part as well as the electrostatic and the B field must be self-consistently advanced.
Date: January 2, 1985
Creator: Hewett, D. W. & Langdon, A. B.
Object Type: Article
System: The UNT Digital Library
Seismic hazard analysis for the NTS spent reactor fuel test site (open access)

Seismic hazard analysis for the NTS spent reactor fuel test site

An experiment is being directed at the Nevada Test Site to test the feasibility for storage of spent fuel from nuclear reactors in geologic media. As part of this project, an analysis of the earthquake hazard was prepared. This report presents the results of this seismic hazard assessment. Two distinct components of the seismic hazard were addressed: vibratory ground motion and surface displacement. (ACR)
Date: May 2, 1980
Creator: Campbell, K.W.
Object Type: Report
System: The UNT Digital Library
Materials selection of surface coatings in an advanced size reduction facility. [For decommissioned stainless steel equipment] (open access)

Materials selection of surface coatings in an advanced size reduction facility. [For decommissioned stainless steel equipment]

A materials selection test program was conducted to characterize optimum interior surface coatings for an advanced size reduction facility. The equipment to be processed by this facility consists of stainless steel apparatus (e.g., glove boxes, piping, and tanks) used for the chemical recovery of plutonium. Test results showed that a primary requirement for a satisfactory coating is ease of decontamination. A closely related concern is the resistance of paint films to nitric acid - plutonium environments. A vinyl copolymer base paint was the only coating, of eight paints tested, with properties that permitted satisfactory decontamination of plutonium and also performed equal to or better than the other paints in the chemical resistance, radiation stability, and impact tests.
Date: June 2, 1980
Creator: Briggs, J. L. & Younger, A. F.
Object Type: Report
System: The UNT Digital Library
RTNS-II targets: cooling channel collapse under simulated bonding conditions (open access)

RTNS-II targets: cooling channel collapse under simulated bonding conditions

We experimentally determined the pressure limits that can be used to autoclave-bond RTNS-II targets without crushing the internal cooling channels. The maximum pressures are 40 to 55 MPa (6 to 8 ksi) in the 300-to-450/sup 0/C temperature regime.
Date: April 2, 1981
Creator: Ludemann, W.D.; Brady, R.L. & Schumacher, B.J.
Object Type: Report
System: The UNT Digital Library
Incorporation of a circular boundary condition into the program POISSON (open access)

Incorporation of a circular boundary condition into the program POISSON

Two-dimensional problems in electrostatics or magnetostatics frequently are solved numerically by means of relaxation techniques. In many such problems the ''sources'' (charges or currents, and regions of permeable material) lie exclusively within a finite closed boundary curve and the relaxation process in principle then could be confined to the region interior to such a boundary - provided a suitable boundary condition is imposed onto the solution at that boundary. The present notes discuss and illustrate the use of a boundary condition of such a nature as to imply the absence of external sources, in order thereby to avoid the inaccuracies and more extensive meshes present when alternatively a simple Dirichlet or Neumann boundary condition is specified on a somewhat more remote outer boundary.
Date: March 2, 1984
Creator: Caspi, S.; Helm, M. & Laslett, L.J.
Object Type: Report
System: The UNT Digital Library
Investigations of glass structure using fluorescence line narrowing and moleuclar dynamics simulations (open access)

Investigations of glass structure using fluorescence line narrowing and moleuclar dynamics simulations

The local structure at individual ion sites in simple and multicomponent glasses is simulated using methods of molecular dynamics. Computer simulations of fluoroberyllate glasses predict a range of ion separations and coordination numbers that increases with increasing complexity of the glass composition. This occurs at both glass forming and glass modifying cation sites. Laser-induced fluorescence line-narrowing techniques provide a unique probe of the local environments of selected subsets of ions and are used to measure site to site variations in the electronic energy levels and transition probabilities of rare earth ions. These and additional results from EXAFS, neutron and x-ray diffraction, and NMR experiments are compared with simulated glass structures.
Date: July 2, 1982
Creator: Weber, M. J. & Brawer, S. A.
Object Type: Article
System: The UNT Digital Library
Interim report on concreted uranium fines and chips billet curing tests: a basis for resuming shipment of concreted uranium scrap billets (open access)

Interim report on concreted uranium fines and chips billet curing tests: a basis for resuming shipment of concreted uranium scrap billets

Through extensive testing and analyses of the concretion process, billets and shipping conditions, it has been determined that properly cured concreted billets can be safely shipped to National Lead Company of Ohio (NLO), Fernald. During curing, billets will be dried for 26 days prior to shipment with the last 10 days between 54 to 66/sup 0/C (130 to 150/sup 0/F). Such dried billets can withstand temperatures up to 85/sup 0/C (185/sup 0/F). The maximum billet temperature that can be expected to occur in shipment is 50/sup 0/C (123/sup 0/F). Thus, the drying cycle becomes a burning test at temperatures which the billets will not reach during shipment to NLO.
Date: May 2, 1980
Creator: Weakley, E.A.
Object Type: Report
System: The UNT Digital Library