States

ITER CS Model Coil and CS Insert Test Results (open access)

ITER CS Model Coil and CS Insert Test Results

The Inner and Outer modules of the Central Solenoid Model Coil (CSMC) were built by US and Japanese home teams in collaboration with European and Russian teams to demonstrate the feasibility of a superconducting Central Solenoid for ITER and other large tokamak reactors. The CSMC mass is about 120 t, OD is about 3.6 m and the stored energy is 640 MJ at 46 kA and peak field of 13 T. Testing of the CSMC and the CS Insert took place at Japan Atomic Energy Research Institute (JAERI) from mid March until mid August 2000. This paper presents the main results of the tests performed.
Date: September 7, 2000
Creator: Martovetsky, N.; Michael, P.; Minervini, J.; Radovinsky, A.; Takayasu, M.; Thome, R. et al.
Object Type: Article
System: The UNT Digital Library
Surface chemistry effects in finite element modeling of heat transfer in (micron)-fuel cells (open access)

Surface chemistry effects in finite element modeling of heat transfer in (micron)-fuel cells

Equations for modeling surface chemical kinetics by the interaction of gaseous and surface species are presented. The formulation is embedded in a finite element heat transfer code and an ordinary differential equation package is used to solve the surface system of chemical kinetic equations for each iteration within the heat transfer solver. The method is applied to a flow which includes methane and methanol in a microreactor on a chip. A simpler more conventional method, a plug flow reactor model, is then applied to a similar problem. Initial results for steam reforming of methanol are given.
Date: December 7, 2000
Creator: Havstad, M
Object Type: Article
System: The UNT Digital Library
Nondestructive evaluation and assay for the plutonium ceramification test facility (open access)

Nondestructive evaluation and assay for the plutonium ceramification test facility

Lawrence Livermore National Laboratory (LLNL) has conducted design and testing activities of the Nondestructive Assay/Evaluation (NDA/NDE) system that will be installed to support the Plutonium Ceramification Test Facility (PuCTF). PuCTF immobilizes plutonium using the ceramic can-in-canister technology. The overall function of the NDA/NDE System is to ensure that sintered pucks contain the appropriate materials for ceramification process control, special nuclear materials (SNM) accountability, and repository acceptance. The system accepts sample pucks from the ceramification system, performs measurements, and determines if the product pucks are acceptable. This report details the conceptual system that is being developed.
Date: March 7, 2000
Creator: Mitchell, M.; Pugh, D. & Wang, T. F.
Object Type: Article
System: The UNT Digital Library
Discretization and iterative solution techniques for elliptic problems on non-matching grids (open access)

Discretization and iterative solution techniques for elliptic problems on non-matching grids

Construction, analysis and numerical testing of efficient solution techniques for solving elliptic PDEs that allow for parallel implementation have been the focus of the research. A number of discretization and solution methods for solving second order elliptic problems that include mortar and penalty approximations and domain decomposition methods for finite elements and finite volumes have been investigated and analyzed. Techniques for parallel domain decomposition algorithms in the framework of PETC and HYPRE have been studied and tested. Hierarchical parallel grid refinement and adaptive solution methods have been implemented and tested on various model problems.
Date: November 7, 2000
Creator: Lazarov, R & Pasciak, J
Object Type: Report
System: The UNT Digital Library
National Ignition Facility Project: An Update (open access)

National Ignition Facility Project: An Update

The National Ignition Facility (NIF) consists of 192 forty-centimeter-square laser beams and a 10-m-diameter target chamber. Physical construction began in 1997. The Laser and Target Area Building and the Optics Assembly Building were the first major construction activities, and despite several unforeseen obstacles, the buildings are now 92% complete and have been done on time and within cost. Prototype component development and testing has proceeded in parallel. Optics vendors have installed full-scale production lines and have done prototype production runs. The assembly and integration of the beampath infrastructure has been reconsidered and a new approach has been developed. This paper will discuss the status of the NIF project and the plans for completion. It will also include summary information on Laser MegaJoule (LMJ) provided by M. Andre, LMJ Project Director.
Date: December 7, 2000
Creator: Hogan, W J; Moses, E; Warner, B; Sorem, M; Soures, J & Hands, J
Object Type: Article
System: The UNT Digital Library
AGE AND ORIGIN OF BASE- AND PRECIOUS-METAL VEINS OF THE COEUR D'ALENE MINING DISTRICT, IDAHO (open access)

AGE AND ORIGIN OF BASE- AND PRECIOUS-METAL VEINS OF THE COEUR D'ALENE MINING DISTRICT, IDAHO

Ore-bearing quartz-carbonate veins of the Coeur d'Alene mining district yield {sup 87}Sr/{sup 86}Sr ratios of 0.74 to >1.60 for low-Rb/Sr, carbonate gangue minerals, similar to current ranges measured in Middle Proterozoic, high-Rb/Sr rocks of the Belt Supergroup. Stable-isotope and fluid-inclusion studies establish a genetic relationship between vein formation and metamorphic-hydrothermal systems of the region. These extraordinary {sup 87}Sr/{sup 86}Sr ratios require accumulation of radiogenic {sup 87}Sr in a high Rb/Sr system over an extended period prior to incorporation of Sr into the veins by hydrothermal processes. Evaluation of the age and composition of potential sources of highly radiogenic Sr indicates that the ore-bearing veins of the Coeur d'Alene district formed within the last 200 Ma from components scavenged from sedimentary and metasedimentary rocks of the Belt Supergroup, the primary host-rocks of the district. These results are consistent with a Cretaceous or Early Tertiary age for these veins. Pb-Zn deposits that yield Pb isotope, K-Ar, and Ar-Ar results indicative of a Proterozoic age probably formed during deposition or diagenesis of the Belt Supergroup at 1350-1500 Ma, possibly as Sullivan-type syngenetic deposits. K-Ar and Rb-Sr apparent ages and {delta}{sup 18}O values of Belt Supergroup rocks decrease southward from the Coeur d'Alene district …
Date: November 7, 2000
Creator: Fleck, R J; Criss, R E; Eaton, G F; Cleland, R W; Wavra, C S & Bond, W D
Object Type: Report
System: The UNT Digital Library
Hanford Seismic Annual Report and Fourth Quarter Report for Fiscal Year 1999 (open access)

Hanford Seismic Annual Report and Fourth Quarter Report for Fiscal Year 1999

This report provides the seismic record at Hanford for FY 1998. Hanford Seismic Monitoring provides an uninterrupted collection of high-quality raw and processed seismic data from the Hanford Seismic Network (HSN) for the U.S. Department of Energy and its contractors. Hanford Seismic Monitoring also locates and identifies sources of seismic activity and monitors changes in the historical pattern of seismic activity at the Hanford Site. The data are compiled, archived, and published for use by the Hanford Site for waste management, Natural Phenomena Hazards assessments, and engineering design and construction. In addition, the seismic monitoring organization works with the Hanford Site Emergency Services Organization to provide assistance in the event of a significant earthquake on the Hanford Site. The HSN and the Eastern Washington Regional Network (EWRN) consist of 40 individual sensor sites and 15 radio relay sites maintained by the Hanford Seismic Monitoring staff. A major reconfiguration of the HSN was initiated at the end of this quarter and the results will be reported in the first quarter report for next fiscal year (FY 2000). For the HSN, there were 390 triggers during the fourth quarter of fiscal year (FY) 1999 on the primary recording system. With the implementation …
Date: January 7, 2000
Creator: Hartshorn, Donald C.; Reidel, Steve P. & Rohay, Alan C.
Object Type: Report
System: The UNT Digital Library
Evidence of biogenic corrosion of titanium after exposure to a continuous culture of thiobacillus ferrooxidans grown in thiosulfate medium (open access)

Evidence of biogenic corrosion of titanium after exposure to a continuous culture of thiobacillus ferrooxidans grown in thiosulfate medium

Experiments were undertaken to evaluate extreme conditions under which candidate materials intended for use in a proposed nuclear waste repository might be susceptible to corrosion by endogenous microorganisms. Thiobucillus ferrooxidans, a sulfur-oxidizing bacterium, was grown in continuous culture using thiosulfate as an energy source; thiosulfate is oxidized to sulfate as a metabolic endproduct by this organism. Culture conditions were optimized to produce a high-density, metabolically active culture throughout a period of long term incubation in the presence of Alloy 22 (a high nickel-based alloy) and Titanium grade 7 (Tigr7) material coupons. After seven months incubation under these conditions, material coupons were withdrawn and analyzed by high resolution microscopy and energy dispersive x-ray analyses. Alloy 22 coupons showed no detectable signs of corrosion. Tigr7, however, demonstrated distinct roughening of the coupon surface, and [presumably solubilized and precipitated] titanium was detected on Alloy 22 coupons incubated in the same T. ferrooxiduns culture vessel. Control coupons of these materials incubated in sterile thiosulfate medium did not demonstrate any signs of corrosion, thus showing that observed corrosive effects were due to the T. ferrooxidans metabolic activities. T. ferrooxidans intermediates of thiosulfate oxidation or sulfate may have caused the corrosive effects observed on Tigr7.
Date: December 7, 2000
Creator: Horn, J M; Martin, S I & Masterson, B
Object Type: Article
System: The UNT Digital Library
HADES-CCG, a new tomographic reconstruction tool (open access)

HADES-CCG, a new tomographic reconstruction tool

We have developed a new tomography code, HADES-CCG. This code uses HADES, a radiographic simulation code, to perform forward- and back-projection and is coupled to a Constrained Conjugate Gradient (CCG) optimizer. An iterative solution to the reconstruction problem is found which is optimal, given the detector noise model, a source model and the appropriate attenuation cross-sections. By explicitly including experimental effects in forward- and back-projection, these effects are not folded back into the object model.
Date: September 7, 2000
Creator: Martz, H. E., Jr.; Aufderheide, M. B., III; Hall, J.; Schach von Wittenau, A.; Goodman, D.; Logan, C. et al.
Object Type: Article
System: The UNT Digital Library
Inertial fusion technology spin-offs-history provides a glimpse of the future (open access)

Inertial fusion technology spin-offs-history provides a glimpse of the future

The development and demonstration of inertial fusion is incredibly challenging because it requires simultaneously controlling and precisely measuring parameters at extreme values in energy, space, and time. The challenges range from building megajoule (10{sup 6} J) drivers that perform with percent-level precision to fabricating targets with submicron specifications to measuring target performance at micron scale (10{sup -6} m) with picosecond (10{sup -12} s) time resolution. Over the past 30 years in attempting to meet this challenge, the inertial fusion community around the world has invented new technologies in lasers, particle beams, pulse power drivers, diagnostics, target fabrication, and other areas. These technologies have found applications in diverse fields of industry and science. Moreover, simply assembling the teams with the background, experience, and personal drive to meet the challenging requirements of inertial fusion has led to spin-offs in unexpected directions, for example, in laser isotope separation, extreme ultraviolet (EUV) lithography for microelectronics, compact and inexpensive radars, advanced laser materials processing, and medical technology. It is noteworthy that more than 40 R&D 100 awards, the ''Oscars of applied research'' have been received by members of the inertial fusion community over this period. Not surprisingly, the inertial fusion community has created many new …
Date: March 7, 2000
Creator: Powell, H
Object Type: Thesis or Dissertation
System: The UNT Digital Library
High intensity laser interactions with atomic clusters (open access)

High intensity laser interactions with atomic clusters

The development of ultrashort pulse table top lasers with peak pulse powers in excess of 1 TW has permitted an access to studies of matter subject to unprecedented light intensities. Such interactions have accessed exotic regimes of multiphoton atomic and high energy-density plasma physics. Very recently, the nature of the interactions between these very high intensity laser pulses and atomic clusters of a few hundred to a few thousand atoms has come under study. Such studies have found some rather unexpected results, including the striking finding that these interactions appear to be more energetic than interactions with either single atoms or solid density plasmas. Recent experiments have shown that the explosion of such clusters upon intense irradiation can expel ions from the cluster with energies from a few keV to nearly 1 MeV. This phenomenon has recently been exploited to produce DD fusion neutrons in a gas of exploding deuterium clusters. Under this project, we have undertaken a general study of the intense femtosecond laser cluster interaction. Our goal is to understand the macroscopic and microscopic coupling between the laser and the clusters with the aim of optimizing high flux fusion neutron production from the exploding deuterium clusters or the …
Date: August 7, 2000
Creator: Ditmire, T
Object Type: Report
System: The UNT Digital Library
Extraction from the Accumulator With Rectangular Momentum Distributions (open access)

Extraction from the Accumulator With Rectangular Momentum Distributions

Antiprotons for the Collider will be bunched in the Accumulator using a RF system (ARF4) that operates at a frequency that is four times the revolution frequency of the Accumulator. Four bunches can be extracted from the Accumulator in a single transfer. Since the TEVATRON will operate with 36 antiproton bunches, nine extractions from the Accumulator will be needed. During Run 1, the momentum distribution of the Accumulator core was shaped by the core cooling systems and was approximately gaussian. After an antiproton bunch was extracted from the core, the momentum spread of the beam was increased because of RF displacement. The beam would then be recooled which would delay shot setup (or the phase space density of subsequent extractions would be diluted). Since the number of extractions per shot for Run II is increasing by 50% (from 6 to 9), the extra time due to re-cooling (or the alternative of momentum phase space dilution) might not be acceptable. This note will outline a scheme that will shape the momentum distribution into a rectangle and will extract the beam from the edges of the distribution so that RF displacement is minimized.
Date: May 7, 2000
Creator: McGinnis, Dave
Object Type: Report
System: The UNT Digital Library
Dynamics of Supersymmetric SU(n_c) and USp(2n_c) Gauge Theories (open access)

Dynamics of Supersymmetric SU(n_c) and USp(2n_c) Gauge Theories

We study dynamical flavor symmetry breaking in the context of a class of N=1 supersymmetric SU(n_c) and USp(2 n_c) gauge theories, constructed from the exactly solvable N=2 theories by perturbing them with small adjoint and generic bare hypermultiplet (quark) masses. We find that the flavor U(n_f) symmetry in SU(n_c) theories is dynamically broken to $U(r)\times U(n_f-r)$ groups for $n_f \leq n_c$. In the r=1 case the dynamical symmetry breaking is caused by the condensation of monopoles in the $\underlinen_f$ representation. For general r, however, the monopoles in the $\underline_n_fC_r$ representation, whose condensation could explain the flavor symmetry breaking but would produce too-many Nambu--Goldstone multiplets, actually"break up'' into"magnetic quarks'' which condense and induce confinement and the symmetry breaking. In USp(2n_c) theories with $n_f\leq n_c + 1$, the flavor SO(2n_f) symmetry is dynamically broken to U(n_f), but with no description in terms of a weakly coupled local field theory. In both SU(n_c) and USp(2 n_c) theories, with larger numbers of quark flavors, besides the vacua with these properties, there exist also vacua with no flavor symmetry breaking.
Date: January 7, 2000
Creator: Carlino, Giuseppe; Konishi, Kenichi & Murayama, Hitoshi
Object Type: Article
System: The UNT Digital Library
Maximum Alpha to Minimum Fission Pulse Amplitude for a Parallel-Plate and Hemispherical Cf-252 Ion-Chamber Instrumented Neutron Source (open access)

Maximum Alpha to Minimum Fission Pulse Amplitude for a Parallel-Plate and Hemispherical Cf-252 Ion-Chamber Instrumented Neutron Source

In an instrumented Cf-252 neutron source, it is desirable to distinguish fission events which produce neutrons from alpha decay events. A comparison of the maximum amplitude of a pulse from an alpha decay with the minimum amplitude of a fission pulse shows that the hemispherical configuration of the ion chamber is superior to the parallel-plate ion chamber.
Date: December 7, 2000
Creator: Oberer, R.B.
Object Type: Report
System: The UNT Digital Library
Prototype Tests for the Recovery and Conversion of UF<sub>6</sub>Chemisorbed in NaF Traps for the Molten Salt Reactor Remediation Project (open access)

Prototype Tests for the Recovery and Conversion of UF<sub>6</sub>Chemisorbed in NaF Traps for the Molten Salt Reactor Remediation Project

The remediation of the Molten Salt Reactor Experiment (MSRE) site includes the removal of about 37 kg of uranium. Of that inventory, about 23 kg have already been removed from the piping system and chemisorbed in 25 NaF traps. This material is being stored in Building 3019. The planned recovery of {approx}11 kg of uranium from the fuel salt will generate another 15 to 19 NaF traps. The remaining 2 to 3 kg of uranium are present in activated charcoal beds, which are also scheduled to be removed from the reactor site. Since all of these materials (NaF traps and the uranium-laden charcoal) are not suitable for long-term storage, they will be converted to a chemical form [uranium oxide (U{sub 3}O{sub 8})], which is suitable for long-term storage. This document describes the process that will be used to recover and convert the uranium in the NaF traps into a stable oxide for long-term storage. Included are a description of the process, equipment, test results, and lessons learned. The process was developed for remote operation in a hot cell. Lessons learned from the prototype testing were incorporated into the process design.
Date: June 7, 2000
Creator: Del Cul, G.D.
Object Type: Report
System: The UNT Digital Library
TRIAXIAL AND SHEAR TESTING OF SELECTED BACKFILL MATERIALS (open access)

TRIAXIAL AND SHEAR TESTING OF SELECTED BACKFILL MATERIALS

The Subsurface Performance Testing Section is performing tests in the Department of Energy's Atlas Facility to evaluate the performance of various backfill materials. Triaxial and shear tests were conducted on select backfill materials. The specific materials tested were: crushed tuff, overton sand, 4- 10 silica sand, 1/4'' dolostone/marble, and limestone. The objective of this report is to provide an estimated value for Poisson's ratio, determine internal friction angle, and stress-strain modulus of the backfill materials that were tested. These basic parameters are necessary for the selection of a backfill material to be included in the repository. This report transmits the results in both hardcopy and electronic formats plus describes the methodology and interpretation of the results. No conclusions will be drawn about the test results, as this will be the purview of other reports. The scope of this report is to use the triaxial and shear testing information and calculate, the internal friction angle, stress-strain modulus, and provide an estimate of Poisson's ratio (Sowers 1979, p. 199) of the selected backfill materials. Standard laboratory procedures, mentioned in Section 2 of this report, were used.
Date: August 7, 2000
Creator: Kramer, N. E.
Object Type: Report
System: The UNT Digital Library
Subsurface Transport Over Reactive Multiphases (STORM): A General, Coupled, Nonisothermal Multiphase Flow, Reactive Transport, and Porous Medium Alteration Simulator, Version 2, User's Guide (open access)

Subsurface Transport Over Reactive Multiphases (STORM): A General, Coupled, Nonisothermal Multiphase Flow, Reactive Transport, and Porous Medium Alteration Simulator, Version 2, User's Guide

N/A
Date: March 7, 2000
Creator: Bacon, Diana H.; White, Mark D. & McGrail, B. Peter
Object Type: Report
System: The UNT Digital Library
SUSPENDING THE GAS TAX: ANALYSIS OF S. 2285 (open access)

SUSPENDING THE GAS TAX: ANALYSIS OF S. 2285

None
Date: April 7, 2000
Creator: unknown
Object Type: Report
System: The UNT Digital Library
FOOD STAMPS: BACKGROUND AND FUNDING (open access)

FOOD STAMPS: BACKGROUND AND FUNDING

This report gives an overview of the background and funding of the food stamps program.
Date: November 7, 2000
Creator: Richardson, Joe
Object Type: Report
System: The UNT Digital Library
President Clinton’s Vetoes (open access)

President Clinton’s Vetoes

This report provides a table outlining the bills vetoed by President William Jefferson Clinton's two terms in office. It includes an overview and the bill number, date, title, and override attempts for each veto.
Date: October 7, 2000
Creator: Galemore, Gary L.
Object Type: Report
System: The UNT Digital Library
China's Automobile Industry and WTO Accession (open access)

China's Automobile Industry and WTO Accession

None
Date: July 7, 2000
Creator: Lum, Thomas
Object Type: Report
System: The UNT Digital Library
China-U.S. Trade Agreements: Compliance Issues (open access)

China-U.S. Trade Agreements: Compliance Issues

None
Date: December 7, 2000
Creator: Morrison, Wayne M.
Object Type: Report
System: The UNT Digital Library
Department of Defense Anthrax Vaccination (open access)

Department of Defense Anthrax Vaccination

None
Date: November 7, 2000
Creator: Bowman, Steven R.
Object Type: Report
System: The UNT Digital Library
Presidential Authority to Create a National Monument on the Coastal Plain of the Arctic National Wildlife Refuge, and Possible Effects of Designation (open access)