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COG validation: SINBAD Benchmark Problems
We validated COG, a 3D Monte Carlo radiation transport code, against experimental data and MNCP4C simulations from the Shielding Integral Benchmark Archive Database (SINBAD) compiled by RSICC. We modeled three experiments: the Osaka Nickel and Aluminum sphere experiments conducted at the OKTAVIAN facility, and the liquid oxygen experiment conducted at the FNS facility. COG results are in good agreement with experimental data and generally within a few % of MCNP results. There are several possible sources of discrepancy between MCNP and COG results: (1) the cross-section database versions are different, MCNP uses ENDFB VI 1.1 while COG uses ENDFB VIR7, (2) the code implementations are different, and (3) the models may differ slightly. We also limited the use of variance reduction methods when running the COG version of the problems.
Date:
February 23, 2004
Creator:
Lent, E M; Sale, K E; Buck, R M & Descalle, M
Object Type:
Report
System:
The UNT Digital Library
Gas Pressure Forming of Titanium Alloys and Composites by Transformation Superplasticity
By thermally cycling through their transformation temperature range, coarse-grained, polymorphic materials can be deformed superplastically, owing to the emergence of transformation mismatch plasticity (or transformation superplasticity) as a deformation mechanism. This mechanism is investigated under biaxial stress conditions during thermal cycling of unalloyed titanium, Ti-6Al-4V, and their composites (Ti/10 vol.% TiC{sub p}, Ti-6Al-4V/10 vol% TiC{sub p} and Ti-6Al-4V/5 vol.% TiB{sub w}). During gas-pressure dome bulging experiments, the dome height was measured as a function of forming time. Adapting existing models of biaxial doming to the case of transformation superplasticity where the strain-rate sensitivity is unity, we verify the operation of this deformation mechanism in all experimental materials, and compare the biaxial results to uniaxial thermal cycling results on the same materials. Finally, existing thickness distribution models are compared with experimentally measured profiles.
Date:
October 23, 2001
Creator:
Frary, M; Schuh, C & Dunand, D C
Object Type:
Article
System:
The UNT Digital Library
Diagnostic Systems Approach to Watershed Management
The water quality of discharge from the surface water system is ultimately dictated by land use and climate within the watershed. Water quality has vastly improved from point source reduction measures, yet, non-point source pollutants continue to rise. 30 to 40% of rivers still do not meet water quality standards for reasons that include impact from urban storm water runoff, agricultural and livestock runoff, and loss of wetlands. Regulating non-point source pollutants proves to be difficult since specific dischargers are difficult to identify. However, parameters such as dissolved organic carbon (DOC) limit the amounts of chlorination due to simultaneous disinfection by-product formation. The concept of watershed management has gained much ground over the years as a means to resolve non-point source problems. Under this management scheme stakeholders in a watershed collectively agree to the nature and extent of non-point sources, determine water quality causes using sound scientific approaches, and together develop and implement a corrective plan. However, the ''science'' of watershed management currently has several shortcomings according to a recent National Research Council report. The scientific component of watershed management depends on acquiring knowledge that links water quality sources with geographic regions. However, there is an observational gap in this …
Date:
February 23, 2001
Creator:
Davisson, M L
Object Type:
Report
System:
The UNT Digital Library
Shock-Dispersed-Fuel Charges: Combustion in Chambers and Tunnels
None
Date:
April 23, 2003
Creator:
Neuwald, P; Reichenbach, H & Kuhl, A L
Object Type:
Article
System:
The UNT Digital Library
Astronomy Applications of Adaptive Optics at Lawrence Livermore National Laboratory
Astronomical applications of adaptive optics at Lawrence Livermore National Laboratory (LLNL) has a history that extends from 1984. The program started with the Lick Observatory Adaptive Optics system and has progressed through the years to lever-larger telescopes: Keck, and now the proposed CELT (California Extremely Large Telescope) 30m telescope. LLNL AO continues to be at the forefront of AO development and science.
Date:
April 23, 2003
Creator:
Bauman, B J & Gavel, D T
Object Type:
Article
System:
The UNT Digital Library
Comparison Between Keyhole Weld Model and Laser Welding Experiments
A series of laser welds were performed using a high-power diode-pumped continuous-wave Nd:YAG laser welder. In a previous study, the experimental results of those welds were examined, and the effects that changes in incident power and various welding parameters had on weld geometry were investigated. In this report, the fusion zones of the laser welds are compared with those predicted from a laser keyhole weld simulation model for stainless steels (304L and 21-6-9), vanadium, and tantalum. The calculated keyhole depths for the vanadium and 304L stainless steel samples fit the experimental data to within acceptable error, demonstrating the predictive power of numerical simulation for welds in these two materials. Calculations for the tantalum and 21-6-9 stainless steel were a poorer match to the experimental values. Accuracy in materials properties proved extremely important in predicting weld behavior, as minor changes in certain properties had a significant effect on calculated keyhole depth. For each of the materials tested, the correlation between simulated and experimental keyhole depths deviated as the laser power was increased. Using the model as a simulation tool, we conclude that the optical absorptivity of the material is the most influential factor in determining the keyhole depth. Future work will …
Date:
September 23, 2002
Creator:
Wood, B C; Palmer, T A & Elmer, J W
Object Type:
Report
System:
The UNT Digital Library
BROOKHAVEN NATIONAL LABORATORY DRAFT INSTITUTIONAL PLAN, FY2004 -- FY2008.
None
Date:
September 23, 2003
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Synthesis of Amino- and Nitro-Substituted Heterocycles as Insensitive Energetic Materials
In this paper we will describe the synthesis of several amino- and nitro-substituted heterocycles, examples from a continuing research project targeted at the synthesis of new, insensitive energetic materials that possess at least 80% the power of HMX (28% more power than TATB). Recently we reported the synthesis and scale-up of the insensitive energetic material, 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105). The energy content (81% the power of HMX) and thermal stability of LLM-105 make it a viable candidate material for insensitive boosters and deep oil perforation. We will report on recent synthetic improvements and several performance and safety tests performed on LLM-105, including a 1 in. cylinder shot and plate dent. We will also report on the synthesis and characterization of 4-amino-3,5-dinitropyrazole (LLM-116), an interesting new insensitive energetic material with a measured crystal density of 1.90 g/cc, to our knowledge the highest density yet measured for a five-membered heterocycle containing amino- and nitro-substituents. LLM-116 was synthesized by reacting 3,5-dinitropyrazole with 1,1,1-trimethylhydrazinium iodide (TMHI) in DMSO in the presence of base. The synthesis and characterization of 4-amino-5-nitro-1,2,3-triazole (ANTZ) and 43-dinitro-1,2,3-triazole (DNTZ), first described by Baryshnikov and coworkers, will also be presented along with the synthesis of several new energetic materials derived from ANTZ and …
Date:
August 23, 2001
Creator:
Pagoria, P. F.; Lee, G. S.; Mitchell, A. R. & Schmidt, R. D.
Object Type:
Article
System:
The UNT Digital Library
SEA - A Simplified Employee Assessment
This paper presents a proposal for modifying the current employee annual evaluation process in SCAD. It purports to simplify that process, primarily by breaking up the resultant document into a set of more or less independent components. It claims to reduce the overall time and effort required from each actor.
Date:
April 23, 2001
Creator:
Busby, L
Object Type:
Report
System:
The UNT Digital Library
National Atmospheric Release Advisory Center Internet Client (NARAC I Client) On-Line Help System Documentation
None
Date:
July 23, 2001
Creator:
Belles, R.; Fischer, K.; Foster, K.; Foster, C.; Gash, J. & Stewart, J.
Object Type:
Text
System:
The UNT Digital Library
Lawrence Livermore National Laboratory Measurements of Plutonium-bearing Oxide in DOE-STD-3013-2000 Containers Using Calorimetry and Gamma Isotopic Analyses
Lawrence Livermore National Laboratory (LLNL) routinely uses calorimetry and gamma isotopic analyses (Cal/Iso) for the accountability measurement of plutonium (Pu) bearing items. In the past 15 years, the vast majority of those items measured by Cal/Iso were contained in a thin-walled convenience can enclosed in another thin-walled outer container. However, LLNL has recently begun to use DOE-STD-3013-2000 containers as well. These DOE-STD-3013-2000 containers are comprised of a stainless steel convenience can enclosed in welded stainless steel primary and secondary containers. In addition to the fact that the wall thickness of the DOE-STD-3013-2000 containers is much greater than that of other containers in our experience, the DOE-STD-3013-2000 containers appear to have larger thermal insulation characteristics. To date, we have derived Pu-mass values from Cal/Iso measurements of 74 different DOE-STD-3013-2000 containers filled with Pu-bearing oxide or mixed uranium-plutonium (U-Pu) oxide material. Both water-bath and air-bath calorimeters were used for these measurements and both use software to predict when thermal equilibrium is attained. Our experience has shown that after apparent equilibrium has been attained, at least one more complete cycle, and sometimes two or three more complete cycles, is required to gain a measure of true thermal equilibrium. Otherwise, the derived Pu-mass values …
Date:
June 23, 2004
Creator:
Dearborn, D M & Keeton, S C
Object Type:
Article
System:
The UNT Digital Library
Comparison of Three Afterglow Morphologies
Herein we compare three functional families for afterglow morphologies: the homogeneous afterglow with constant shock surface energy density, the structured afterglow for which the energy density decays as a power-law as a function of viewer angle, and the gaussian afterglow which has an exponential decay of energy density with viewer angle. We simulate observed lightcurves and polarization curves for each as seen from a variety of observer vantage points. We find that the homogeneous jet is likely inconsistent with observations and suggest that the future debate on the structure of afterglow jets will be between the other two candidates.
Date:
December 23, 2003
Creator:
Salmonson, J D; Rossi, E & Lazzati, D
Object Type:
Article
System:
The UNT Digital Library
LDRD Final Report - 01-FS-004
This report describes the results from an experimental program to investigate the feasibility of laser produced MeV protons as a diagnostic of electric fields or shock compressed materials. The experimental campaign was very successful, and has led to substantial advances in the characterization and optimization of proton sources from ultra-intense laser-solid interaction. This is a subject of the highest scientific interest [1] and is highly relevant to developing its use as a possible NIF implosion diagnostic and other applications relevant to stockpile stewardship.
Date:
January 23, 2002
Creator:
Mackinnon, A. J.
Object Type:
Report
System:
The UNT Digital Library
POPULATION KINETICS MODELING FOR NON-LTE AND NON-MAXWELLIAN PLASMAS GENERATED IN FINITE TEMPERATURE DENSE MATTER EXPERIMENTS ARISING FROM SHORT PULSE X-RAY SOURCE
The short pulse x-ray sources will provide a major advance in dense matter studies important to understand implosion physics for ICF as a generator of warm dense matter or a probe of finite temperature dense matter. The interaction of such a high-energy photon pulse with the initially solid matter creates highly transient states of plasmas initially whose relaxation processes are of interest to the equation of states or spectral properties of these matter. For these plasmas, assumptions such as LTE population distributions or Maxwellian electron energy distributions should be tested by employing a method that does not make these assumption a priori. Our goal is to present a model that can be used to simulate the electron distributions, the ionization balance and the spectral output of transient systems generated in the future ICF experiments. We report on the progress in developing a non-LTE atomic population kinetics code integrated with Boltzmann equation solver to provide a self-consistent time-dependent solution of the level populations and the particle energy distributions.
Date:
December 23, 2003
Creator:
Chung, H; Lee, R W & Morgan, W L
Object Type:
Article
System:
The UNT Digital Library
Functional One-Dimensional Lipid Bilayers on Carbon Nanotube Templates
We present one-dimensional (1-D) lipid bilayer structures that integrate carbon nanotubes with a key biological environment-phospholipid membrane. Our structures consist of lipid bilayers wrapped around carbon nanotubes modified with a hydrophilic polymer cushion layer. Despite high bilayer curvature, the lipid membrane maintains its fluidity and can sustain repeated damage-recovery cycles. We also present the first evidence of spontaneous insertion of pore-forming proteins into 1-D lipid bilayers. These structures could lead to the development of new classes of biosensors and bioelectronic devices.
Date:
July 23, 2004
Creator:
Artyukhin, Alexander; Shestakov, Alexei; Harper, Jennifer; Bakajin, Olgica; Stroeve, Pieter & Noy, Aleksandr
Object Type:
Article
System:
The UNT Digital Library
Multiple Oscillation Stabilizing Control
This paper presents a strategy that may be used to guide stabilizing control design for multiple oscillations, which are difficult to control using conventional control design procedures. A multiple oscillation phenomena is observed in an example power system. A local bifurcation and an interarea bifurcation develop in an example power system due to multiple bifurcation parameter variations. The dynamic behaviors of the bifurcating system are complex due to the overlapping of the two different bifurcation subsystems and are shown to be difficult to control. The double bifurcations are studied in this paper and in order to stabilize them, three kind of {mu}-synthesis robust controls are designed, (a) {mu}-synthesis power system stabilizer (MPSS); (b) {mu}-synthesis SVC control (MSVC); and (c) a mixed MPSS/MSVC control. Based on the bifurcation subsystem analysis, the measurement signals and locations of the controls are selected. The control performances of three kind of controls are evaluated and compared. The conclusions are given according to the analysis and time simulation results.
Date:
July 23, 2004
Creator:
Yue, M.; Schlueter, R.; Azarm, M. & Bari, R.
Object Type:
Article
System:
The UNT Digital Library
Nonlinear optical absorption in laser modified regions of fused silica substrates
The presence of strong nonlinear absorption has been observed in laser modified fused silica. Intensity-dependent transmission measurements using 355-nm, 532-nm and 1,064-nm laser pulses were performed in pristine polished regions in fused silica substrates and in locations that were exposed to dielectric breakdown. The experimental results suggest that multi-photon absorption is considerably stronger in the modified regions compared to pristine sites and is strongly dependent on the excitation wavelength.
Date:
March 23, 2004
Creator:
Walser, A D; Demos, S; Etienne, M & Dorsinville, R
Object Type:
Article
System:
The UNT Digital Library
A Database of LLNL Sensor Technologies
None
Date:
July 23, 2003
Creator:
Twogood, R E & O'Brien, K
Object Type:
Report
System:
The UNT Digital Library
FROM THE ISR TO RHIC - MEASUREMENTS OF HARD-SCATTERING AND JETS USING INCLUSIVE SINGLE PARTICLE PRODUCTION AND 2-PARTICLE CORRELATIONS.
Hard scattering in p-p collisions, discovered at the CERN ISR in 1972 by the method of leading particles, proved that the partons of Deeply Inelastic Scattering strongly interacted with each other. Further ISR measurements utilizing inclusive single or pairs of hadrons established that high p{sub T} particles are produced from states with two roughly back-to-back jets which are the result of scattering of constituents of the nucleons as described by Quantum Chromodynamics (QCD), which was developed during the course of these measurements. These techniques, which are the only practical method to study hard-scattering and jet phenomena in Au+Au central collisions at RHIC energies, are reviewed, as an introduction to present RHIC measurements.
Date:
April 23, 2005
Creator:
Tannenbaum, M. J.
Object Type:
Article
System:
The UNT Digital Library
RCRA Assessment Plan for Single-Shell Tank Waste Management Area T at the Hanford Site
A groundwater quality assessment plan was prepared to investigate the rate and extent of aquifer contamination beneath Waste Management Area T at the Hanford Site in Washington State. This plan is an update of a draft plan issued in January 1999, which guided work performed in fiscal year 2000.
Date:
February 23, 2001
Creator:
Hodges, Floyd N. & Chou, Charissa J.
Object Type:
Report
System:
The UNT Digital Library
Molten Salt Oxidation: A Thermal Technology for Waste Treatment and Demilitarization
MSO is a good alternative to incineration for the treatment of a variety of organic wastes including obsolete explosives, low-level mixed waste streams, PCB contaminated oils, spent resins and carbon. The Lawrence Livermore National Laboratory (LLNL) has demonstrated the MSO process for the effective destruction of explosives, explosives-contaminated materials, and other wastes on a 1.5 kg/hr bench-scale unit and in an integrated MSO facility capable of treating 8 kg/hr of low-level radioactive mixed wastes. LLNL, under the direction and support of the Joint Demilitarization Technology (JDT) program, is currently building an integrated MSO plant for destroying explosives, explosives-contaminated sludge and explosives-contaminated activated charcoal. In a parallel effort, LLNL also provides technical support to DOE for the implementation of the MSO technology at industrial scale at Richland, Washington. Over 30 waste streams have been demonstrated with LLNL-built MSO systems. In this paper we will present our latest experimental data, our operational experience with MSO and also discuss its process capabilities.
Date:
August 23, 2001
Creator:
Hsu, P C; Watkins, B; Pruneda, C & Kwak, S
Object Type:
Article
System:
The UNT Digital Library
Thermodynamic Model of Afterburning in Explosions
Thermodynamic states encountered during afterburning of explosion products gases in air were analyzed with the Cheetah code. Results are displayed in the form of Le Chatelier diagrams: the locus of states of specific internal energy versus temperature, for six different condensed explosives charges. Accuracy of the results was confirmed by comparing the fuel and products curves with the heats of detonation and combustion, and species composition as measured in bomb calorimeter experiments. Results were fit with analytic functions u = f ( T ) suitable for specifying the thermodynamic properties required for gas-dynamic models of afterburning in explosions.
Date:
April 23, 2003
Creator:
Kuhl, A L; Howard, M & Fried, L
Object Type:
Article
System:
The UNT Digital Library
Charge-state distribution and Doppler effect in an expanding photoionized plasma
None
Date:
February 23, 2004
Creator:
Foord, M E; Heeter, R F; Thoe, R S; Chung, H; Liedahl, D A; Goldstein, W H et al.
Object Type:
Article
System:
The UNT Digital Library
Thermal Decomposition of Trinitrotoluene (TNT) with a New One-Dimensional Time to Explosion (ODTX) Apparatus
The thermal explosion of trinitrotoluene (TNT) is used as a basis for evaluating the performance of a new One-Dimensional-Time-to-Explosion (ODTX) apparatus. The ODTX experiment involves holding a 12.7 mm-diameter spherical explosive sample under confinement (150 MPa) at a constant elevated temperature until the confining pressure is exceeded by the evolution of gases during chemical decomposition. The resulting time to explosion as a function of temperature provides valuable decomposition kinetic information. A comparative analysis of the measurements obtained from the new unit and an older system is presented. Discussion on selected performance aspects of the new unit will also be presented. The thermal explosion of TNT is highly dependent on the material. Analysis of the time to explosion is complicated by historical and experimental factors such as material variability, sample preparation, temperature measurement and system errors. Many of these factors will be addressed. Finally, a kinetic model using a coupled thermal and heat transport code (chemical TOPAZ) was used to match the experimental data.
Date:
March 23, 2001
Creator:
Tran, T. D.; Simpson, R. L.; Maienschein, J. & Tarver, Craig M.
Object Type:
Article
System:
The UNT Digital Library