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A 2-D Self-Consistent DSMC Model for Chemically Reacting Low Pressure Plasma Reactors
This paper will focus on the methodology of using a 2D plasma Direct Simulation Monte Carlo technique to simulate the species transport in an inductively coupled, low pressure, chemically reacting plasma system. The pressure in these systems is typically less than 20 mtorr with plasma densities of approximately 10{sup 17} {number_sign}/m{sup 3} and an ionization level of only 0.1%. This low ionization level tightly couples the neutral, ion, and electron chemistries and interactions in a system where the flow is subsonic. We present our strategy and compare simulation results to experimental data for Cl{sub 2} in a Gaseous Electronics Conference (GEC) reference cell modified with an inductive coil.
Date:
June 17, 1999
Creator:
Bartel, Timothy J.; Economou, Demetre & Johannes, Justine E.
Object Type:
Article
System:
The UNT Digital Library
2 MV Injector as the Elise Front-End and as an Experimental Facility
We report on progress in the preparation of the 2 MV Injector at LBNL as the front-end of Elise, and as a multi-purpose experimental facility for Heavy Ion Fusion beam dynamics studies. Recent advances on the performance and understanding of the injector are described, and some of the on-going experimental activities are summarized.
Date:
December 7, 1999
Creator:
Yu, S. S.; Eylon, S.; Henestroza, E.; Peters, C.; Reginato, L.; Tauschwitz, A. et al.
Object Type:
Report
System:
The UNT Digital Library
3-D Finite Element Analyses of the Egan Cavern Field
Three-dimensional finite element analyses were performed for the two gas-filled storage caverns at the Egan field, Jennings dome, Louisiana. The effects of cavern enlargement on surface subsidence, storage loss, and cavern stability were investigated. The finite element model simulated the leaching of caverns to 6 and 8 billion cubic feet (BCF) and examined their performance at various operating conditions. Operating pressures varied from 0.15 psi/ft to 0.9 psi/ft at the bottom of the lowest cemented casing. The analysis also examined the stability of the web or pillar of salt between the caverns under differential pressure loadings. The 50-year simulations were performed using JAC3D, a three dimensional finite element analysis code for nonlinear quasistatic solids. A damage criterion based on onset of dilatancy was used to evaluate cavern instability. Dilation results from the development of microfractures in salt and, hence, potential increases in permeability onset occurs well before large scale failure. The analyses predicted stable caverns throughout the 50-year period for the range of pressures investigated. Some localized salt damage was predicted near the bottom walls of the caverns if the caverns are operated at minimum pressure for long periods of time. Volumetric cavern closures over time due to creep were …
Date:
February 1, 1999
Creator:
Klamerus, E.W. & Ehgartner, B.L.
Object Type:
Report
System:
The UNT Digital Library
3-D Measurement of Deformation Microstructure of Al(0.2%)Mg Using Submicron Resolution White X-Ray Microbeams
We have used submicron-resolution white x-ray microbeams on the MHATT-CAT beamline 7-ID at the Advanced Photon Source to develop techniques for three-dimensional investigation of the deformation microstructure in a 20% plane strain compressed Al(0.2%)Mg tri-crystal. Kirkpatrick-Baez mirrors were used to focus white radiation from an undulator to a 0.7 x 0.7 {micro}m{sup 2} beam that was scanned over bi- and tri-crystal regions near the triple-junction of the tri-crystal. Depth resolution along the x-ray microbeam of less than 5 microns was achieved by triangulation to the diffractibn source point using images taken at a series of CCD distances from the microbeam. Computer indexing of the deformation cell structure in the bi-crystal region provided orientations of individual subgrains to {approximately}0.01 degrees, making possible detailed measurements of the rotation axes between individual cells.
Date:
November 29, 1999
Creator:
Larson, B. C.; tamura, N.; Chung, J.-S.; Ice, G. E.; Budai, J. D.; Tischler, J. Z. et al.
Object Type:
Article
System:
The UNT Digital Library
3-D Ray-tracing and 2-D Fokker-Planck Simulations of Radiofrequency Application to Tokamak Plasmas
A state of the art numerical tool has been developed to simulate the propagation and the absorption of coexisting different types of waves in a tokamak geometry. The code includes a numerical solution of the three-dimensional (R, Z, {Phi}) toroidal wave equation for the electric field of the different waves in the WKBJ approximation. At each step of integration, the two-dimensional (v{sub {parallel}}, v{sub {perpendicular}}) Fokker-Planck equation is solved in the presence of quasilinear diffusion coefficients. The electron Landau damping of the waves is modeled taking into account the interaction of the wave electric fields with the quasilinearly modified distribution function. Consistently, the code calculates the radial profiles of non-inductively generated current densities, the transmitted power traces and the total power damping curves. Synergistic effects among the different type of waves (e.g., lower hybrid and ion Bernstein waves) are studied through the separation of the contributions of the single wave from the effects due to their coexistence.
Date:
May 1, 1999
Creator:
Cardinali, A.; Paoletti, F. & Bernabei, S.
Object Type:
Report
System:
The UNT Digital Library
3-D Silicon Photonic Lattices- Cornerstone of an Emerging Photonics Revolution
Three-dimensional photonic lattices are engineered materials which are the photonic analogues of semiconductors. These structures were first proposed and demonstrated in the mid-to-late 1980's. However, due to fabrication difficulties, lattices active in the infrared are only just emerging. Wide ranges of structures and fabrication approaches have been investigated. The most promising approach for many potential applications is a diamond-like structure fabricated using silicon microprocessing techniques. This approach has enabled the fabrication of 3-D silicon photonic lattices active in the infrared. The structures display band gaps centered from 12{micro} down to 1.55{micro}.
Date:
July 8, 1999
Creator:
Fleming, J.G. & Lin, Shawn-Yu
Object Type:
Article
System:
The UNT Digital Library
3-D Target Location from Stereoscopic SAR Images
SAR range-Doppler images are inherently 2-dimensional. Targets with a height offset lay over onto offset range and azimuth locations. Just which image locations are laid upon depends on the imaging geometry, including depression angle, squint angle, and target bearing. This is the well known layover phenomenon. Images formed with different aperture geometries will exhibit different layover characteristics. These differences can be exploited to ascertain target height information, in a stereoscopic manner. Depending on the imaging geometries, height accuracy can be on the order of horizontal position accuracies, thereby rivaling the best IFSAR capabilities in fine resolution SAR images. All that is required for this to work are two distinct passes with suitably different geometries from any plain old SAR.
Date:
October 1, 1999
Creator:
Doerry, Armin W.
Object Type:
Report
System:
The UNT Digital Library
The 4-8 GHz Stochastic Cooling Upgrade for the Fermilab Debuncher
During the Fermilab Collider Run II, the Main Injector is expected to provided a three-fold increase in flux of the proton beam sent to the antiproton production target as compared to the previous Collider Run Ib. This increase in antiproton production rate to 20 x 10{sup 10} antiprotons/hour will be handled by upgrading the stochastic cooling systems in both the Debuncher and Accumulator rings of the Fermilab Antiproton Source. In the Debuncher ring, the upgrade calls for increasing the stochastic cooling system bandwidth from 2-4 to 4-8 GHz. The effective front-end noise temperature of the cooling systems will also be lowered from 125K to 35K. This paper will discuss some details of the system design of the new 4-8 GHz cooling systems in the Debuncher Ring.
Date:
January 1, 1999
Creator:
McGinnis, D.
Object Type:
Report
System:
The UNT Digital Library
5/10-MVA high temperature superconducting power transformer. Progress report for the period May 1998 - June 1999
None
Date:
July 28, 1999
Creator:
Intermagnetics General Corporation
Object Type:
Report
System:
The UNT Digital Library
(6)Li, (7)Li Nuclear Magnetic Resonance Investigation of Lithium Coordination in Binary Phosphate Glasses
{sup 6}Li and {sup 7}Li solid state magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy has been used to investigate the local coordination environment of lithium in a series of xLi{sub 2}O {center_dot} (1-x)P{sub 2}O{sub 5} glasses, where 0.05 {le} x {le} 0.55. Both the {sup 6}Li and {sup 7}Li show chemical shift variations with changes in the Li{sub 2}O concentration, but the observed {sup 6}Li NMR chemical shifts closely approximate the true isotropic chemical shift and can provide a measure of the lithium bonding environment. The {sup 6}Li NMR results indicate that in this series of lithium phosphate glasses the Li atoms have an average coordination between four and five. The results for the metaphosphate glass agree with the coordination number and range of chemical shifts observed for crystalline LiPO{sub 3}. An increase in the {sup 6}Li NMR chemical shift with increasing Li{sub 2}O content was observed for the entire concentration range investigated, correlating with increased cross-linking of the phosphate tetrahedral network by O-Li-O bridges. The {sup 6}Li chemical shifts were also observed to vary monotonically through the anomalous glass transition temperature (T{sub g}) minimum. This continuous chemical shift variation shows that abrupt changes in the Li coordination …
Date:
February 8, 1999
Creator:
Alam, T.M.; Boyle, T.J.; Brow, R.K. & Conzone, S.
Object Type:
Article
System:
The UNT Digital Library
The 8.4 MW Modulator/Regulator Power Systems for the Electron Cyclotron Heating Facility Upgrade at DIII-D
Over the next three years the DIII-D National Fusion Facility at General Atomics will upgrade its electron cyclotron heating (ECH) capability from the present 3 MW at 110 GHz to 10 MW of injected microwave power. There will be ten gyrotron tubes supplied by five 8.4 MW modulator/regulator (M/R) power systems. The project has gained considerable leverage from the acquisition of surplus hardware from the MFTF program that was conducted at LLNL in the early 1980s. One of these systems had been refurbished and converted for use as an ECH power supply earlier. The experience gained and the lessons learned from operating that system have proved valuable in guiding the engineering of the new systems. This paper provides an overview of the power system design and a report on the present status of the project.
Date:
December 1999
Creator:
Pronko, S. G. E. & Baggest, D. S.
Object Type:
Article
System:
The UNT Digital Library
15.4% CuIn1-XGaXSe2-Based Photovoltaic Cells from Solution-Based Precursor Films
We have fabricated 15.4%- and 12.4%-efficient CuIn1-XGaXSe2 (CIGS)-based photovoltaic devices from solution-based electrodeposition (ED) and electroless-deposition (EL) precursors. As-deposited precursors are Cu-rich CIGS. Additional In, Ga, and Se are added to the ED and EL precursor films by physical vapor deposition (PVD) to adjust the final film composition to CuIn1-XGaXSe2. The ED and EL device parameters are compared with those of a recent world record, an 18.8%-efficient PVD device. The tools used for comparison are current voltage, capacitance voltage, and spectral response characteristics.
Date:
May 25, 1999
Creator:
Bhattacharya, R. N.; Batchelor, W.; Contreras, M. A.; Noufi, R. N. (National Renewable Energy Laboratory); Hiltner, J. F. & Sites, J. R. (Department of Physics, Colorado State University)
Object Type:
Article
System:
The UNT Digital Library
94-A13 Native American Initiative Short Course Management Plan
A training program conducted in Bartlesville by BDM-Oklahoma technical staff, which included geologists, geophysicists, exploration and drilling specialists, and environmental policy experts. The proposed training schedule offered four courses per year and included those coursed identified by the tribes in the survey. The training program was outlined for members of Native American Tribes whose lands have oil and gas resources. The proposed program contributed to meeting the goals of the U.S. Department of Energy's (DOE) Domestic Oil and Gas Initiative to help Native American tribes become more self-sufficient in developing and managing their resources through training in cost-effective, improved technologies for hydrocarbon production that will meet environmental regulations. The training program outlined was for adult tribal representatives who are responsible for managing tribal mineral holdings or setting policy, or who work in the oil and gas industry. The course content is in response to a survey that was developed by BDM-Oklahoma and sent in the Spring of 1995 to 26 tribal agencies identified through previous contact with DOE. Tribes were asked to indicate course content needs, levels, preferred time of year, and location. Six tribes responded with specific recommendations and needs. These tribes, were the Creek, Pueblo, Cherokee, St. Regis …
Date:
April 27, 1999
Creator:
Carroll, Herbert B.; Johnson, William I. & Kokesh, Judith H.
Object Type:
Report
System:
The UNT Digital Library
97-ERD-022 final report: Supernova on Nova
This is the final year of the 3-year LDRD-ERD involving Lasers, D&NT, Physics, and ILSA to develope astrophysics experiments on intense lasers such as the Nova and Gekko lasers. During this 3 year period, we have developed a highly successful experiment probing the hydrodynamics of the explosion phase of core-collapse supernovae, which occurs during the first ~3 hours after core collapse. This was in collaboration with the Univ. of Arizona and CEA/Saclay. We also developed a very successful experiment to probe the hydrodynamics of the later time, young remnant phase, meaning the first ~10-20 years after core collapse. This was in collaboration with the Univ. of Michigan and Univ. of Colorado. Finally, we developed during the final year an exquisite experiment to probe the dynamics of radiative, high Mach number astrophysical jets, in collaboration with the Univ. of Maryland and Osaka Univ. Each experiment has received very high visibility, with a multitude of publications, both in the technical journals (most importantly, the astrophysical journals) and in the popular press. The attached publication list shows 25 papers published or submitted to technical journals, 5 articles appearing in the popular press (including a cover story of Sky and Telescope), and 65 conference …
Date:
March 11, 1999
Creator:
Remington, B. A.
Object Type:
Report
System:
The UNT Digital Library
100-D Area In Situ Redox Treatability Test for Chromate-Contaminated Groundwater: FY 1998 Year-End Report
A treatability test was conducted for the In Situ Redox Manipulation (ISRM) technology at the US Department of Energy's Hanford, Washington 100D Area. The target contaminant was dissolved chromate [Cr(VI)] in groundwater. The ISRM technology involves creating a permeable subsurface treatment zone to reduce mobile chromate in groundwater to an insoluble form. The ISRM permeable treatment zone is created by reducing ferric iron [Fe(III)] to ferrous iron [Fe(II)] within the aquifer sediments. This is accomplished by injecting aqueous sodium dithionite into the aquifer and withdrawing the reaction products. The goal of the treatability test was to create a linear ISRM barrier by injecting sodium dithionite into five wells. Well installation and site characterization activities began in the spring of 1997. The first dithionite injection took place in September 1997. The results of this first injection were monitored through the spring of 1998; the remaining four dithionite injections were carried out in May through July of 1998. These five injections created a reduced zone in the Hanford unconfined aquifer 150 feet in length (perpendicular to groundwater flow) by 50 feet wide. The reduced zone extended over the thickness of the unconfined zone, which is approximately 15 feet. Analysis of recent groundwater …
Date:
April 15, 1999
Creator:
Williams, M. D.; Vermeul, V. R.; Szecsody, J. E.; Fruchter, J. S. & Cole, C. R.
Object Type:
Report
System:
The UNT Digital Library
A 100-kV, 2-kA, 2.5-{micro}S Pulser for Developing and Calibrating Long-Pulse Diagnostics
The development of voltage and current probes for measuring an electron beam's current and position associated with several microsecond-long pulses from advanced Linear Induction Accelerators requires a precision pulser that can deliver both high voltages and high currents to a diagnostics Test Line. Seven-stage, type-E PFNs have been utilized in both a transformer and 4-stage Marx (plus/minus) configuration. The resulting 50-ohm pulser delivers to the Test Line a repeatable 100 kV, ca. 2 {micro}s flat-top ({+-} 1%), 2.5 {micro}s FWHM pulse with a rise time of 175 ns and 500 ns for the transformer and Marx options, respectively. Methods of reducing the rise time for both options are discussed and modeled. The coaxial Test Line is insulated at up to two atmospheres with SF{sub 6} and includes two transition regions to hold and test different diameter beam current and position monitors (BPMs). The center conductor incorporates both translation and tip/tilt with an accuracy of 100 {micro}m. Finally, the line is terminated in a matched radial resistor that provides a planar region at fields up to 40 kV/cm for the testing of voltage probes. Both the transformer and Marx options are modeled and compared to experimental results.
Date:
June 27, 1999
Creator:
Carlson, R.L.
Object Type:
Article
System:
The UNT Digital Library
AZ-101 Mixer Pump Demonstration Data Acquisition System and Gamma Cart Data Acquisition Control System Software Configuration Management Plan
This Software Configuration Management Plan (SCMP) provides the instructions for change control of the AZ1101 Mixer Pump Demonstration Data Acquisition System (DAS) and the Sludge Mobilization Cart (Gamma Cart) Data Acquisition and Control System (DACS).
Date:
December 29, 1999
Creator:
White, D. A.
Object Type:
Report
System:
The UNT Digital Library
105-K Basin Material Design Basis Feed Description for Spent Nuclear Fuel (SNF) Project Facilities VOL 1 Fuel
Metallic uranium Spent Nuclear Fuel (SNF) is currently stored within two water filled pools, 105-KE Basin (KE Basin) and 105-KW Basin (KW Basin), at the United States Department of Energy (U.S. DOE) Hanford Site, in southeastern Washington State. The Spent Nuclear Fuel Project (SNF Project) is responsible to DOE for operation of these fuel storage pools and for the 2100 metric tons of SNF materials that they contain. The SNF Project mission includes safe removal and transportation of all SNF from these storage basins to a new storage facility in the 200 East Area. To accomplish this mission, the SNF Project modifies the existing KE Basin and KW Basin facilities and constructs two new facilities: the 100 K Area Cold Vacuum Drying Facility (CVDF), which drains and dries the SNF; and the 200 East Area Canister Storage Building (CSB), which stores the SNF. The purpose of this document is to describe the design basis feed compositions for materials stored or processed by SNF Project facilities and activities. This document is not intended to replace the Hanford Spent Fuel Inventory Baseline (WHC 1994b), but only to supplement it by providing more detail on the chemical and radiological inventories in the fuel …
Date:
November 4, 1999
Creator:
Packer, M. J.
Object Type:
Report
System:
The UNT Digital Library
The 110 GHz Gyrotron System on DIII-D: Gyrotron Tests and Physics Results
The DIII-D tokamak has installed a system with three gyrotrons at the 1 MW level operating at 110 GHz. Physics experiments on electron cyclotron current drive, heating, and transport have been performed. Good efficiency has been achieved both for on-axis and off-axis current drive with relevance for control of the current density profile leading to advanced regimes of tokamak operation, although there is a difference between off-axis ECCD efficiency inside and outside the magnetic axis. Heating efficiency is excellent and electron temperatures up to 10 keV have been achieved. The gyrotron system is versatile, with poloidal scan and control of the polarization of the injected rf beam. Phase correcting mirrors form a Gaussian beam and focus it into the waveguide. Both perpendicular and oblique launch into the tokamak have been used. Three different gyrotron designs are installed and therefore unique problems specific to each have been encountered, including parasitic oscillations, mode hops during modulation and polarization control problems. Two of the gyrotrons suffered damage during operations, one due to filament failure and one due to a vacuum leak. The repairs and subsequent testing will be described. The transmission system uses evacuated, windowless waveguide and the three gyrotrons have output windows …
Date:
December 1, 1999
Creator:
Lohr, J.; Calahan, P.; Callis, R. W.; Chu, T. S.; deGrassie, J. S.; Gorelov, I. et al.
Object Type:
Article
System:
The UNT Digital Library
(129)Xe NMR of Mesoporous Silicas
The porosities of three mesoporous silica materials were characterized with {sup 129}Xe NMR spectroscopy. The materials were synthesized by a sol-gel process with r = 0, 25, and 70% methanol by weight in an aqueous cetyltrimethylammonium bromide solution. Temperature dependent chemical shifts and spin lattice relaxation times reveal that xenon does not penetrate the pores of the largely disordered (r= 70%) silica. For both r = 0 and 25%, temperature dependent resonances corresponding to physisorbed xenon were observed. An additional resonance for the r = 25% sample was attributed to xenon between the disordered cylindrical pores. 2D NMR exchange experiments corroborate the spin lattice relaxation data which show that xenon is in rapid exchange between the adsorbed and the gas phase.
Date:
April 23, 1999
Creator:
Anderson, M.T.; Asink, R.A.; Kneller, J.M. & Pietrass, T.
Object Type:
Article
System:
The UNT Digital Library
219-S chemical compatibility
This document consists of tables of the materials that make up the ''wetted'' parts of the 219-S waste handling facility and a combination of manufacturer lists of chemicals that are not recommended.
Date:
August 31, 1999
Creator:
Goodwin, L. D.
Object Type:
Report
System:
The UNT Digital Library
The 239 Pu(n,2n)238Pu cross section: preliminary calculations
The primary motivation for the present work is to provide theoretical values for the ratio of the partial <sup>239</sup>Pu(n,2nx{gamma})<sup>238</sup>Pu to total <sup>239</sup> Pu(n,2n)<sup>238</sup>Pu cross section for several discrete gamma transitions. Results and conclusions of preliminary calculations from threshold to 20 MeV are presented. Calculations are based on theoretical models with parameters obtained from the literature or from our ad hoc systematics. Optical model cross sections and transmission coefficients were determined using the coupled-channels method. The calculations included a preequilibrium component followed by multiple particle and gamma-ray emissions. Fission competition was included at all stages of de-excitation. Suggestions for further verifications and possible improvements are provided.
Date:
March 12, 1999
Creator:
Chen, H.; Reffo, G.; Ross, M. A. & White, R. M.
Object Type:
Report
System:
The UNT Digital Library
241-AN-A pit leak detection ANA-WT-LDSTA-331 acceptance test procedure
This document describes the method used to test design criteria for Safety Class, Intrinsically Safe leak detector system installed in 241-AN-A Valve Pit located at 200E Tank Farms. The purpose of this Procedure is to demonstrate that the pit leak detection relay cabinet and intrinsically safe probe circuit is fully operable.
Date:
August 25, 1999
Creator:
VANDYKE, D.W.
Object Type:
Report
System:
The UNT Digital Library
241-AN-A valve pit manifold valves and position indication acceptance test procedure
This document describes the method used to test design criteria for gear actuated ball valves installed in 241-AN-A Valve Pit located at 200E Tank Farms. The purpose of this procedure is to demonstrate the following: Equipment is properly installed, labeled, and documented on As-Built drawings; New Manifold Valves in the 241-AN-A Valve Pit are fully operable using the handwheel of the valve operators; New valve position indicators on the valve operators will show correct valve positions; New valve position switches will function properly; and New valve locking devices function properly.
Date:
August 25, 1999
Creator:
VANDYKE, D.W.
Object Type:
Report
System:
The UNT Digital Library