10-GW CO₂ laser system at the Brookhaven Accelerator Test Facility (open access)

10-GW CO₂ laser system at the Brookhaven Accelerator Test Facility

Design and performance of a high peak-power CO{sub 2} laser system to produce subnanosecond IR pulses for electron acceleration experiment are presented. We discuss theoretical aspects of the picosecond laser pulse propagation in a molecular amplifier and a design approach towards compact Terawatt CO{sub 2} laser systems.
Date: December 31, 1993
Creator: Pogorelsky, I.; Fischer, J. & Fisher, A. S.
System: The UNT Digital Library
A 50-MeV mm-wave electron linear accelerator system for production of tunable short wavelength synchrotron radiation (open access)

A 50-MeV mm-wave electron linear accelerator system for production of tunable short wavelength synchrotron radiation

The Advanced Photon Source (APS) at Argonne in collaboration with the University of Illinois at Chicago and the University of Wisconsin at Madison is developing a new millimeter wavelength, 50-MeV electron linear accelerator system for production of coherent tunable wavelength synchrotron radiation. Modern micromachining techniques based on deep etch x-ray lithography, LIGA (Lithografie, Galvanoformung, Abformung), capable of producing high-aspect ratio structures are being considered for the fabrication of the accelerating components.
Date: December 31, 1993
Creator: Nassiri, A.; Kustom, R. L.; Mills, F. E.; Kang, Y. W.; Matthews, P. J.; Grudzien, D. et al.
System: The UNT Digital Library
1993 Department of Energy Records Management Conference (open access)

1993 Department of Energy Records Management Conference

This document consists of viewgraphs from the presentations at the conference. Topics included are: DOE records management overview, NIRMA and ARMA resources, NARA records management training, potential quality assurance records, filing systems, organizing and indexing technical records, DOE-HQ initiatives, IRM reviews, status of epidemiologic inventory, disposition of records and personal papers, inactive records storage, establishing administrative records, managing records at Hanford, electronic mail -- legal and records issues, NARA-GAO reports status, consultive selling, automated indexing, decentralized approach to scheduling at a DOE office, developing specific records management programs, storage and retrieval at Savannah River Plant, an optical disk case study, and special interest group reports.
Date: December 31, 1993
Creator: unknown
System: The UNT Digital Library
1993 Radiation Protection Workshop: Proceedings (open access)

1993 Radiation Protection Workshop: Proceedings

The 1993 DOE Radiation Protection Workshop was conducted from April 13 through 15, 1993 in Las Vegas, Nevada. Over 400 Department of Energy Headquarters and Field personnel and contractors from the DOE radiological protection community attended the Workshop. Forty-nine papers were presented in eleven separate sessions: Radiological Control Manual Implementation, New Approaches to Instrumentation and Calibration, Radiological Training Programs and Initiatives, External Dosimetry, Internal Dosimetry, Radiation Exposure Reporting and Recordkeeping, Air Sampling and Monitoring Issues, Decontamination and Decommissioning of Sites, Contamination Monitoring and Control, ALARA/Radiological Engineering, and Current and Future Health Physics Research. Individual papers are indexed separately on the database.
Date: December 31, 1993
Creator: unknown
System: The UNT Digital Library
3000 vs. 3600 psig NGV on-board storage pressure evaluation (open access)

3000 vs. 3600 psig NGV on-board storage pressure evaluation

The objective of this evaluation is to perform a comprehensive analysis of two on-board storage pressures or natural gas vehicles. The choice of operating pressure is a fairly complicated one, with implications for a variety of refueling station and vehicle cost issues. Furthermore, the benefit of higher storage pressure operation (increased vehicle driving distance) has been poorly understood, both in precision as well as in value. This study will attempt to combine the relevant factors to aid the industry in developing a framework for deciding the merits of higher operating pressure. This study will not attempt to issue a recommendation on whether the additional cost of 3600 psig storage is justifiable, but will establish a model for decision making.
Date: December 31, 1993
Creator: Biederman, R.; Blazek, C.; Freeman, P. & Gauthier, S.
System: The UNT Digital Library
Abstracts of papers presented at the LVIII Cold Spring Harbor Symposium on quantitative Biology: DNA and chromosomes (open access)

Abstracts of papers presented at the LVIII Cold Spring Harbor Symposium on quantitative Biology: DNA and chromosomes

This volume contains the abstracts of oral and poster presentations made at the LVIII Cold Spring Harbor Symposium on Quantitative Biology entitles DNA & Chromosomes. The meeting was held June 2--June 9, 1993 at Cold Spring Harbor, New York.
Date: December 31, 1993
Creator: unknown
System: The UNT Digital Library
The accelerated testing of cements in brines (open access)

The accelerated testing of cements in brines

Cementitious materials may be employed in settings where they face prolonged exposure to Mg-rich brines. This study evaluated the possibility of using high temperatures to accelerate brine-cement reaction rates. Class-H cement coupons were tested in Mg-K-Na-C1- SO{sub 4} brines to 100{degrees}C. MgC1{sub 2}-NaC1 solutions were also employed in a test sequence that extended to 200{degrees}C. It was found that accelerated testing could be used successfully to evaluate the compatability of cementitious materials with such brines.
Date: December 31, 1993
Creator: Krumhansl, J. L.
System: The UNT Digital Library
Acceleration in astrophysics (open access)

Acceleration in astrophysics

The origin of cosmic rays and applicable laboratory experiments are discussed. Some of the problems of shock acceleration for the production of cosmic rays are discussed in the context of astrophysical conditions. These are: The presumed unique explanation of the power law spectrum is shown instead to be a universal property of all lossy accelerators; the extraordinary isotropy of cosmic rays and the limited diffusion distances implied by supernova induced shock acceleration requires a more frequent and space-filling source than supernovae; the near perfect adiabaticity of strong hydromagnetic turbulence necessary for reflecting the accelerated particles each doubling in energy roughly 10{sup 5} to {sup 6} scatterings with negligible energy loss seems most unlikely; the evidence for acceleration due to quasi-parallel heliosphere shocks is weak. There is small evidence for the expected strong hydromagnetic turbulence, and instead, only a small number of particles accelerate after only a few shock traversals; the acceleration of electrons in the same collisionless shock that accelerates ions is difficult to reconcile with the theoretical picture of strong hydromagnetic turbulence that reflects the ions. The hydromagnetic turbulence will appear adiabatic to the electrons at their much higher Larmor frequency and so the electrons should not be scattered …
Date: December 31, 1993
Creator: Colgate, S. A.
System: The UNT Digital Library
Accident simulation in a chemical process facility at the Savannah River Site. Revision 1 (open access)

Accident simulation in a chemical process facility at the Savannah River Site. Revision 1

The US Department of Energy requires Westinghouse Savannah River Company to safely operate the chemical separations facilities at the Savannah River Site (SRS). As part of the safety analysis program, simulation of a proposed frame waste recovery (FWR) system is needed to determine the possible accident consequences that may affect public safety. This paper details the simulation process for the proposed frame waste recovery process and describes the analytical tools used in order to make estimates of accident consequences. Since the process in question has been operated, historical data and statistics about its operation are available. Software tools have been developed to allow analysis of the frame waste recovery system, including the generation of system specific dose conversion factors for a number of unique situations. Accident scenarios involving spilled liquid material are analyzed and account for the specific floor geometry of the facility. Confinement and filtration systems are considered. Analysis of source terms is a limiting factor which affects the entire evaluation process. In the past, facility source terms were generally constant with occasional variations from established patterns. As new site missions unfold, significant variations in source terms can be expected. The impact of these variations on the safety analysis …
Date: December 31, 1993
Creator: Hope, E. P.
System: The UNT Digital Library
Adsorption of water to the metal/polymer interface studied by neutron and X-ray reflectivity (open access)

Adsorption of water to the metal/polymer interface studied by neutron and X-ray reflectivity

Neutron reflectivity is among the few techniques able to probe a buried interface. Through the use of isotopic labeling, complicated interface structures may be determined with a resolution on the order of 5 {angstrom}. However, for highly complex thin film and interface structures, it is often necessary to perform complementary experiments to reduce the number of unknown variables, and thus enable an unambiguous interpretation of the neutron reflectivity. To this end, the authors have combined X-ray and neutron reflectivity to study changes in a metal/polymer interface (molybdenum/polyurethane, hereafter Mo/PU) upon exposure to a humid environment. In particular, the authors have tracked the adsorption of moisture to the interface and variations in the density of the interphase. This information was obtained as a function of the concentration of a silane coupling agent added to the bulk of the PU. Adhesion of the Mo/PU interface is important to programs in the DOE complex. This paper reports the first results of this study.
Date: December 31, 1993
Creator: Kent, M. S.; McIntyre, D. C.; Smith, G. S.; Baker, S.; Wages, S.; Nyitray, A. et al.
System: The UNT Digital Library
Advanced staged combustion system for power generation (open access)

Advanced staged combustion system for power generation

To respond to the increasing market need for a new generation of plants with a substantial improvement in efficiency and a reduction in capital cost, the Institute of Gas Technology has developed an advanced staged, fluidized-bed combustion system concept. The staged fluidized-bed partial combustor produces the fuel gas at about 1500 F. The fuel gas, after particulate removal, is directed to a gas turbine followed by a steam cycle. Adequate sulfur capture and solids waste stabilization are attained by separating calcination, carbonization, and gasification/combustion steps in the staged fluidized beds. Intermediate gas cooling is avoided during the process to maximize the power production. The coal-to-electricity conversion efficiency of the system approaches 49 percent, which exceeds the efficiencies of the other emerging technologies.
Date: December 31, 1993
Creator: Rehmat, A. & Goyal, A.
System: The UNT Digital Library
Advances in rapid prototyping (open access)

Advances in rapid prototyping

Recent advances in stereolithography and selective laser sintering have had a significant impact on the overall quality of parts produced using these rapid prototyping processes. The development and implementation of 3D System`s QuickCast{trademark} resin and software for building investment casting patterns have proven to be major steps toward fabricating highly accurate patterns with very good surface finishes. Sandia uses patterns generated from rapid prototyping processes to reduce the cycle time and cost of fabricating prototype parts in support of a Sandia National Laboratories managed program called FASTCAST. As participants in the Beta test program for QuickCast{trademark} resin and software, they experienced a steep learning curve and were able to build accurate parts in a short period of time. It is now possible, using this technology, to produce highly accurate prototype parts as well as acceptable firs article and small lots size production parts. They use the Selective Laser Sintering (SLS) process to fabricate prototype wax patterns for investment casting. DTM Corporation recently introduced the use of their polycarbonate material for fabricating investment casting patterns. The polycarbonate material is processed significantly faster, with improved strength, dimensional stability, and without a support structure during the build process. Sandia is currently changing from …
Date: December 31, 1993
Creator: Atwood, C. L.; McCarty, G. D.; Pardo, B. T. & Bryce, E. A.
System: The UNT Digital Library
Advances in tunable powerful lasers: The advanced free-electron laser (open access)

Advances in tunable powerful lasers: The advanced free-electron laser

In the past several decades, remarkable progress in laser science and technology has made it possible to obtain laser light from the ultra-violet to the far infra-red from a variety of laser types, and at power levels from milliwatts to kilowatts (and, some day, megawatts). However, the availability of tunable lasers at ``high`` power (above a few tens of watts) is more limited. Figure 1, an assessment of the availability of tunable lasers, shows the covered range to be about 400 to 2000 nanometers. A variety of dye lasers cover the visible and near infra red, each one of which is tunable over approximately a 10% range. In the same region, the TI:saphire laser is adjustable over a 20 to 25% range. And finally, optical parametric oscillators can cover the range from about 400 nanometers out to about 2000 nm (even farther at reduced energy output). The typical output energy per pulse may vary from a few to one hundred millijoules, and since repetition rates of 10 to 100 Hertz are generally attainable, average output powers of tens of watts are possible. In recent years, a new approach to powerful tunable lasers -- the Free-Electron Laser (FEL) -- has emerged. …
Date: December 31, 1993
Creator: Singer, S. & Sheffield, R.
System: The UNT Digital Library
Aerial robotic data acquisition system (open access)

Aerial robotic data acquisition system

A small, unmanned aerial vehicle (UAV), equipped with sensors for physical and chemical measurements of remote environments, is described. A miniature helicopter airframe is used as a platform for sensor testing and development. The sensor output is integrated with the flight control system for real-time, interactive, data acquisition and analysis. Pre-programmed flight missions will be flown with several sensors to demonstrate the cost-effective surveillance capabilities of this new technology.
Date: December 31, 1993
Creator: Hofstetter, K. J.; Hayes, D. W.; Pendergast, M. M. & Corban, J. E.
System: The UNT Digital Library
AIAA 94-1214: Using generic tool kits to build intelligent systems (open access)

AIAA 94-1214: Using generic tool kits to build intelligent systems

The Intelligent Systems and Robotics Center at Sandia National Laboratories is developing technologies for the automation of processes associated with environmental remediation and information-driven manufacturing. These technologies, which focus on automated planning and programming and sensor-based and model-based control, are used to build intelligent systems which are able to generate plans of action, program the necessary devices, and use sensors to react to changes in the environment. By automating tasks through the use of programmable devices tied to computer models which are augmented by sensing, requirements for faster, safer, and cheaper systems are being satisfied. However, because of the need for rapid cost-effective prototyping and multi-laboratory teaming, it is also necessary to define a consistent approach to the construction of controllers for such systems. As a result, the Generic Intelligent System Controller (GISC) concept has been developed. This concept promotes the philosophy of producing generic tool kits which can be used and reused to build intelligent control systems.
Date: December 31, 1993
Creator: Miller, D. J.
System: The UNT Digital Library
Algorithmic significance, mutual information, and DNA sequence comparisons (open access)

Algorithmic significance, mutual information, and DNA sequence comparisons

The newly proposed algorithmic significance method [6] enables recognition of patterns in DNA sequences at prespecified significance levels via minimal length encoding. We extend the method to provide a formal framework for DNA sequence comparisons via mutual information. While in this paper we restrict our discussion to DNA sequence analysis, the methods that are presented are potentially applicable in many other domains. Under a few simplifying assumptions, we show that significance of sequence similarity depends exponentially on mutual information. In addition to this estimate of significance, the concept of mutual information provides solutions to the following two problems in DNA sequence comparisons: Factoring out contribution of shared repetitive patterns and factoring out bias due to partial sequencing.
Date: December 31, 1993
Creator: Milosavljevic, A.
System: The UNT Digital Library
Alkylene-bridged polygerm- and polygermsilsesqui-oxanes: New hybrid organic-inorganic materials (open access)

Alkylene-bridged polygerm- and polygermsilsesqui-oxanes: New hybrid organic-inorganic materials

Alkylene-bridge polygerm- and polygermsilsequioxanes have been formed by hydrolysis-condensation of their corresponding (EtO){sub 3}M(CH{sub 2}){sub n}Ge(OEt){sub 3} monomers under HCl- and NEt{sub 3}-catalyzed conditions in ethanol. Solid state {sup 13}C and {sup 29}Si NMR indicate the retention of the alkylene bridging moiety during polymerization. The resulting aerogels are mesoporous materials with high surface areas. Incorporation of the short ethylene bridging unit results in higher surface areas than when heylene bridges are present. The porous nature of hexylene-bridged hybrid network [Si(CH{sub 2}){sub 6}GeO{sub 3}]{sub n} appears insensitive to the acidic or basic nature of the catalyst employed in it formation, in contrast to its polysilsesquioxane counterpart. Work is underway to determine the origin of porosity in these materials, and to characterize xerogel materials generated from these monomers.
Date: December 31, 1993
Creator: Jamison, G. M.; Loy, D. A.; Zender, G. & Shea, K. J.
System: The UNT Digital Library
Analyses of a steel containment vessel with an outer contact structure under severe internal overpressurization conditions (open access)

Analyses of a steel containment vessel with an outer contact structure under severe internal overpressurization conditions

Many Mark-I and Mark-II BWR plants are designed with a steel vessel as the primary containment. Typically, the steel containment vessel (SCV) is enclosed within a reinforced concrete shield building with only a small gap (50--90mm) separating the two structures. This paper describes finite element analyses performed to evaluate the effects of contact and friction between a steel containment vessel and an outer contact structure when the containment vessel is subjected to large internal pressures. These computations were motivated by a joint program on containment integrity involving the Nuclear Power Engineering Corporation (NUPEC) of Japan, the US Nuclear Regulatory Commission (NRC), and Sandia National Laboratories for testing model containments.
Date: December 31, 1993
Creator: Porter, V. L.
System: The UNT Digital Library
Analyses of Greek Research Reactor with mixed HEU-LEU Be reflected core (open access)

Analyses of Greek Research Reactor with mixed HEU-LEU Be reflected core

The fuel-cycle analyses presented in this paper provide specific steps to be taken in the transition from a 36-element water-reflected HEU core to a 33-element LEU equilibrium core with a Be reflector on two faces. The first step will be to install the Be reflector and remove the highest burnup HEU fuel. The smaller Be-reflected core will be refueled with LEU fuel. All analyses were performed using a planar 5-group REBUS3 model benchmarked to VIM Monte Carlo. In addition to fuel cycle results, the control rod worth, reactivity response to increased fuel and water temperature and decreased water density were compared for the transition core and the reference HEU core.
Date: December 31, 1993
Creator: Deen, J. R.; Snelgrove, J. L. & Papastergiou, K.
System: The UNT Digital Library
Analysis of a High Velocity Oxygen-Fuel (HVOF) thermal spray torch. Part 2, Computational results (open access)

Analysis of a High Velocity Oxygen-Fuel (HVOF) thermal spray torch. Part 2, Computational results

The fluid dynamics inside and outside a High Velocity Oxygen-Fuel (HVOF) torch are analyzed using computational fluid dynamic (CFD) techniques. The thermal spray device analyzed is similar to a Metco Diamond Jet torch with powder injection. The spray nozzle is axisymmetric with powder injected on the centerline, premixed fuel and oxygen fed from an annulus, and air cooling injected along the interior surface of the aircap choked flow conditions occur at the exit of the aircap and a supersonic, under-expanded jet develops externally. The details of the CFD simulation are given in a companion paper. This paper describes the general gas dynamic features of HVOF spraying and then gives a detailed discussion of the computational predictions of the present analysis. The gas velocity, temperature, pressure and Mach number distributions are presented for various locations inside and outside the torch. Characteristics of the metal spray particle velocity, temperature, Mach number, trajectory, and phase state (solid or liquid) are also presented and discussed. Extensive numerical flow visualization is provided to show flow features such as mixing layers, shock waves, and expansion waves.
Date: December 31, 1993
Creator: Oberkampf, W. L. & Talpallikar, M.
System: The UNT Digital Library
Analysis of concrete containment structures under severe accident loading conditions (open access)

Analysis of concrete containment structures under severe accident loading conditions

One of the areas of current interest in the nuclear power industry is the response of containment buildings to internal pressures that may exceed design pressure levels. Evaluating the response of structures under these conditions requires computing beyond design load to the ultimate load of the containment. For concrete containments, this requirement means computing through severe concrete cracking and into the regime of wide-spread plastic rebar and/or tendon response. In this regime of material response, an implicit code can have trouble converging. This paper describes some of the author`s experiences with Version 5.2 of ABAQUS Standard and the ABAQUS concrete model in computing the axisymmetric response of a prestressed concrete containment to ultimate global structural failure under high internal pressures. The effects of varying the tension stiffening parameter in the concrete material model and variations of the parameters for the CONTROLS option are discussed.
Date: December 31, 1993
Creator: Porter, V. L.
System: The UNT Digital Library
Analysis of deep seismic reflection and other data from the southern Washington Cascades (open access)

Analysis of deep seismic reflection and other data from the southern Washington Cascades

Limited possibilities exist for new hydrocarbon exploration regimes in the Pacific Northwest. Extensive geophysical studies have been used to outline a proposed sedimentary basin hidden beneath volcanic rocks of the Cascades region of southwestern Washington (Stanley et. al, 1992, AAPG Bull. 76, 1569--1585). Electrical geophysical imaging using the magnetotelluric (MT) method first detected thick, electrically conductive sequences believed to represent late Cretaceous to Oligocene marine sedimentary rocks. The conductive section occurs at depths from about 1 km to 10 km in the area west of a line between Mt. Rainier and Mt. Adams, extending westward to a line between Mt. St. Helens and just west of Morton, WA. The conductive rocks reaches thicknesses as great as 10 km. The anomalous rocks appear to be very near the surface in the axis of anticanes that bring Eocene marine shales to shallow depths. Careful consideration of physical properties and the correspondence of the morphology of the units to known fold sets suggests that the high conductivities are related to lithologic/stratigraphic units rather than to variations in physical properties. Our preference for the lithology of the anomalous section, based upon a study of regional geology and structure, is one dominated by marine shales …
Date: December 31, 1993
Creator: Stanley, W. D. & Johnson, S. Y.
System: The UNT Digital Library
Analysis of the high energy behavior of the forward scattering parameters -- {sigma}{sub tot}, {rho}, and B (open access)

Analysis of the high energy behavior of the forward scattering parameters -- {sigma}{sub tot}, {rho}, and B

Recent experimental results, namely, the remeasurement of the {rho} value by UA4/2 at {radical}s = 546 GeV, together with a new analysis by the E710 group of {sigma}{sub tot}, {rho} and B at {radical}s = 1800 GeV, as well as their measurement of {sigma}{sub tot} and B at {radical}s = 1020 GeV, have provided important anchor points for the high energy behavior of {anti p}p scattering. The authors analyze high energy {anti p}p and pp data, using two distinct (and dissimilar) analysis techniques: (1) asymptotic amplitude analysis, under the assumption that they have reached {open_quotes}asymptopia{close_quotes}, and (2) an eikonal model whose amplitudes are designed to mimic real QCD amplitudes. The former gives strong evidence for a log (s/s{sub 0}) dependence at current energies and not log{sup 2}(s/s{sub 0}), and demonstrates that odderons are not necessary to explain the experimental data. The latter gives a unitary model for extrapolation into true {open_quote}asymptopia{close_quote} from current energies, allowing them to predict the values of the total cross section at future supercolliders. Using their QCD-model, the authors obtain {sigma}{sub tot}(16 TeV)= 106 {+-} 4 mb and {sigma}{sub tot}(40 TeV) = 120 {+-} 5 mb.
Date: December 31, 1993
Creator: Block, M. M.; Halzen, F.; Margolis, B. & White, A. R.
System: The UNT Digital Library
Analysis of transposon-insertion mutants of Clostridium acetobutylicum ATCC 824 (open access)

Analysis of transposon-insertion mutants of Clostridium acetobutylicum ATCC 824

None
Date: December 31, 1993
Creator: Mattsson, D. M. & Rogers, P.
System: The UNT Digital Library