Relative x-ray backlighter intensity comparison of ti and ti/sc combination foils driven in double-sided and single-sided laser configuration (open access)

Relative x-ray backlighter intensity comparison of ti and ti/sc combination foils driven in double-sided and single-sided laser configuration

Use of multiple backlighter foils and/or double-sided laser interaction geometry with backlit imaging can result in improved backlighter efficiency. An experimental comparison of backlighter intensity for Ti foils and Ti/Sc combination foils in both the one-sided and double-sided laser-interaction configuration is presented. Spectrally-integrated framing camera images show intensity contributions of front and rear backlighter surfaces for both foil types. Analysis of time-resolved x-ray spectra collected from foil targets show the relative contribution of Ti and Sc 2-1 He-like resonance lines to the total backlighter intensity.
Date: June 5, 2000
Creator: Bullock, A. B.; Landen, O. L. & Bradley, D. K.
Object Type: Article
System: The UNT Digital Library
Final Focus Shielding Designs for Modern Heavy-Ion Fusion Power Plant Designs (open access)

Final Focus Shielding Designs for Modern Heavy-Ion Fusion Power Plant Designs

Recent work in heavy-ion fusion accelerators and final focusing systems shows a trend towards less current per beam, and thus, a greater number of beams. Final focusing magnets are susceptible to nuclear heating, radiation damage, and neutron activation. The trend towards more beams, however, means that there can be less shielding for each magnet, Excessive levels of nuclear heating may lead to magnet quench or an intolerable recirculating power for magnet cooling. High levels of radiation damage may result in short magnet lifetimes and low reliability. Finally, neutron activation of the magnet components may lead to difficulties in maintenance, recycling, and waste disposal. The present work expands upon previous, three-dimensional magnet shielding calculations for a modified version of the HYLIFE-I1 IFE power plant design. We present key magnet results as a function of the number of beams.
Date: July 5, 2000
Creator: Latkowski, J. F. & Meier, W. R.
Object Type: Article
System: The UNT Digital Library
Search for simultaneous optical counterparts of gamma-ray bursts (open access)

Search for simultaneous optical counterparts of gamma-ray bursts

Gamma Ray Bursts (GRBs) are brief, randomly located, releases of gamma-ray energy from unknown celestial sources that occur almost daily. The study of GRBs has undergone a revolution in the past three years due to an international effort of follow-up observations made possible by the instantaneous distribution of reliable GRB coordinate information over the internet provided by NASA's GCN (GRB Coordinates Network). The 3-year LDRD project described here, done in collaboration with the workers responsible for the GCN, was the very first serious system to actively utilize the GCN and thus played a major role in the development of the GCN and the dramatic increase in our understanding of GRBs. The scientific objective of this project was to measure the intensity of any prompt visible radiation accompanying the gamma-ray emission utilizing a small but sensitive robotic telescope that responded to GCN triggers by rapidly taking images of the GCN error box. The instrument developed for this project, LOTIS, was the first of its kind, and the longest running, collecting data on over 75 GRBs during its 3 year running period. The results of LOTIS and the other follow-up programs have now shown that GRBs are at cosmological distances and interact …
Date: September 5, 2000
Creator: Park, H. S.; Porrata, R. A.; Bionta, R. M. & Williams, G. G.
Object Type: Report
System: The UNT Digital Library
Management Prestart Review Phase 1 for the NIF Optics Assembly Building (OAB) (open access)

Management Prestart Review Phase 1 for the NIF Optics Assembly Building (OAB)

A Management Prestart Review (MPR) for the National Ignition Facility (NIF) Optics Assembly Building (OAB) was conducted from June, 2000, through October, 2000. This review was performed to determine readiness of the facility and management to transfer the facility from the construction to the commissioning and operations phase. This review process provides assurance that the appropriate line management is in place to effect the turnover. Completion and acceptance of this report constitutes a turnover of facility and equipment operational responsibility from the Beampath Infrastructure System Construction organization to the Assembly Installation and Refurbishment Operations (assembly equipment installation/activation and mechanical cleaning operations) and the Beampath Infrastructure System (BIS) Commissioning and Operations Organizations (conventional facility operations). The OAB MPR provides to the NIF Project Manager an independent, systematic assessment of: (1) Readiness of line management for the turnover to take place, (2) Completeness of the equipment and facility installation of the OAB, (3) Readiness of personnel to operate within the facility, and (4) Implementation and efficacy of key management control processes and procedures. The MPR process assures that the technical, cost, and schedule risk associated with the installation/activation of OAB special equipment, mechanical cleaning, and conventional facility operations within the OAB are …
Date: October 5, 2000
Creator: Dragoo, V.
Object Type: Report
System: The UNT Digital Library
Plan of Action: JASPER Management Prestart Review (Surrogate Material Experiment) (open access)

Plan of Action: JASPER Management Prestart Review (Surrogate Material Experiment)

The Lawrence Livermore National Laboratory (LLNL) Joint Actinide Shock Physics Experimental Research (JASPER) Facility is being developed at the Nevada Test Site (NTS) to conduct shock physics experiments on special nuclear material and other actinide materials. JASPER will use a two-stage, light-gas gun to shoot projectiles at actinide targets. Projectile velocities will range from 1 to 8 km/s, inducing pressures in the target material up to 6 Mbar. The JASPER gas gun has been designed to match the critical dimensions of the two-stage, light-gas gun in Building 341 of LLNL. The goal in copying the LLNL gun design is to take advantage of the extensive ballistics database that exists and to minimize the effort spent on gun characterization in the initial facility start-up. A siting study conducted by an inter-Laboratory team identified Able Site in Area 27 of the NTS as the best location for the JASPER gas gun. Able Site consists of three major buildings that had previously been used to support the nuclear test program. In April 1999, Able Site was decommissioned as a Nuclear Explosive Assembly Facility and turned back to the DOE for other uses. Construction and facility modifications at Able Site to support the JASPER …
Date: December 5, 2000
Creator: Cooper, W E
Object Type: Report
System: The UNT Digital Library
National Ignition Facility Target Chamber (open access)

National Ignition Facility Target Chamber

On June 11, 1999 the Department of Energy dedicated the single largest piece of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) in Livermore, California. The ten (10) meter diameter aluminum target high vacuum chamber will serve as the working end of the largest laser in the world. The output of 192 laser beams will converge at the precise center of the chamber. The laser beams will enter the chamber in two by two arrays to illuminate 10 millimeter long gold cylinders called hohlraums enclosing 2 millimeter capsule containing deuterium, tritium and isotopes of hydrogen. The two isotopes will fuse, thereby creating temperatures and pressures resembling those found only inside stars and in detonated nuclear weapons, but on a minute scale. The NIF Project will serve as an essential facility to insure safety and reliability of our nation's nuclear arsenal as well as demonstrating inertial fusion's contribution to creating electrical power. The paper will discuss the requirements that had to be addressed during the design, fabrication and testing of the target chamber. A team from Sandia National Laboratories (SNL) and LLNL with input from industry performed the configuration and basic design of the target chamber. The method …
Date: October 5, 2000
Creator: Wavrik, R W; Cox, J R & Fleming, P J
Object Type: Article
System: The UNT Digital Library
Minimum probe length for unique identification of all open reading frames in a microbial genome (open access)

Minimum probe length for unique identification of all open reading frames in a microbial genome

In this paper, we determine the minimum hybridization probe length to uniquely identify at least 95% of the open reading frame (ORF) in an organism. We analyze the whole genome sequences of 17 species, 11 bacteria, 4 archaea, and 2 eukaryotes. We also present a mathematical model for minimum probe length based on assuming that all ORFs are random, of constant length, and contain an equal distribution of bases. The model accurately predicts the minimum probe length for all species, but it incorrectly predicts that all ORFs may be uniquely identified. However, a probe length of just 9 bases is adequate to identify over 95% of the ORFs for all 15 prokaryotic species we studied. Using a minimum probe length, while accepting that some ORFs may not be identified and that data will be lost due to hybridization error, may result in significant savings in microarray and oligonucleotide probe design.
Date: March 5, 2000
Creator: Sokhansanj, B. A.; Ng, J. & Fitch, J. P.
Object Type: Article
System: The UNT Digital Library
Diagnostic X-Multi-Axis Beamline (open access)

Diagnostic X-Multi-Axis Beamline

Tomographic reconstruction of explosive events require time resolved multipal lines of sight. Considered here is a four (or eight) line of sight beam layout for a nominal 20 MeV 2000 Ampere 2 microsecond electron beam for generation of x-rays 0.9 to 5 meters from a given point, the ''firing point''. The requirement of a millimeter spatial x-ray source requires that the electron beam be delivered to the converter targets with sub-millimeter precision independent of small variations in beam energy and initial conditions. The 2 usec electron beam pulse allows for four bursts in each line, separated in time by about 500 microseconds. Each burst is divided by a electro-magnetic kicker into four (or eight) pulses, one for each beamline. The arrival time of the four (or eight) beam pulses at the x-ray target can be adjusted by the kicker timing and the sequence that the beams of each burst are switched into the different beamlines. There exists a simple conceptual path from a four beamline to a eight beamline upgrade. The eight line beamline is built up from seven unique types of sub-systems or ''blocks''. The beamline consists of 22 of these functional blocks and contains a total of 455 …
Date: April 5, 2000
Creator: Paul, A C
Object Type: Report
System: The UNT Digital Library
Study of Spatially Resolved Temperature Diagnostics for High Explosives (open access)

Study of Spatially Resolved Temperature Diagnostics for High Explosives

The next generation of 2-D and 3-D weapon-simulation codes will require marked advances in the spatial and temporal resolution of the various diagnostics to verify the complex physics predicted from these calculations. This is particularly true for the complicated physics of high-explosive (HE) detonation and burn, of which a detailed understanding is crucial to nuclear weapons performance and integrity. The processes involved in the detonation of HEs occur very rapidly and lead to extremely high pressures (several GPa) and temperatures (several thousand Kelvin). A key diagnostic that has so far eluded experimentalists is a temperature diagnostic for burning HE. Temperature is a basic thermodynamic property that enables a fundamental understanding of important HE physics such as the chemical processes involved in the shock-to-detonation transition, and to assess the thermal part of the equation-of-state of the detonation products. Accurate, spatially localized temperature measurements with high temporal resolution are thus crucial, but are unfortunately lacking. Our work address this important problem.
Date: April 5, 2000
Creator: Lee, H
Object Type: Report
System: The UNT Digital Library
Measurement of Tritium in Gas Phase Soil Moisture and Helium-3 in Soil Gas at the Hanford Townsite and 100 K Area (open access)

Measurement of Tritium in Gas Phase Soil Moisture and Helium-3 in Soil Gas at the Hanford Townsite and 100 K Area

In 1999, eight soil gas sampling points ranging in depth from 4.9 ft to 32 ft below ground surface (bgs) in two clusters were installed adjacent to well 699-41-1, south of the Hanford Townsite. Fifteen soil gas sampling points, ranging in depth from 7.0 ft to 10.4 ft bgs, were installed to the north and east of the 100-K East Reactor facility. Gas phase soil moisture samples were collected using silica gel traps from all eight sampling locations adjacent to well 699-41-1 and eight locations at the 100-K Area. Soil gas samples for helium-3 measurements were collected at all sampling points. No detectable tritium (<240 pCi/L) was found in the soil moisture samples from either the Hanford Townsite or 100-K Area sampling points. This behavior suggests that tritiated moisture from groundwater is not migrating upward to the sampling points and there are no large vadose zone sources of tritium at either location. Helium-3 analyses of the soil gas samples showed significant enrichments relative to ambient air helium-3 concentrations with a depth dependence consistent with a groundwater source from decay of tritium. Helium-3/helium-4 ratios (normalized to the abundances in ambient air) at the Hanford Townsite ranged from 1.012 at 5 feet …
Date: July 5, 2000
Creator: Olsen, Khris B.; Patton, Gregory W.; Poreda, R.; Dresel, P Evan & Evans, John C.
Object Type: Report
System: The UNT Digital Library
Post-Remediation Biomonitoring of Pesticides in Marine Waters Near the United Heckathorn Site, Richmond, California (open access)

Post-Remediation Biomonitoring of Pesticides in Marine Waters Near the United Heckathorn Site, Richmond, California

Marine sediment remediation at the United Heckathorn Superfund Site was completed in April 1997. Water and mussel tissues were sampled in January 1998 from four stations near Lauritzen Canal in Richmond, California, for the first post-remediation monitoring of marine areas near the United Heckathorn Site. Dieldrin and DDT were analyzed in water samples, tissue samples from resident mussels, and tissue samples from transplanted mussels deployed for 4 months. Concentrations of dieldrin and total DDT in water and total DDT in tissue were compared to pre-remediation data available from the California State Mussel Watch program (tissues) and the Ecological Risk Assessment for the United Heckathorn Superfund Site (tissues and water). Biomonitoring results indicated that pesticides were still bioavailable in the water column, and have not been reduced from pre-remediation levels. Annual biomonitoring will continue to assess the effectiveness of remedial actions at the United Heckathorn Site.
Date: September 5, 2000
Creator: Antrim, Liam D. & Kohn, Nancy P.
Object Type: Report
System: The UNT Digital Library
Fracture Geometry Analysis for the Stratigraphic Units of the Repository Host Horizon (open access)

Fracture Geometry Analysis for the Stratigraphic Units of the Repository Host Horizon

None
Date: September 5, 2000
Creator: Hardin, E.
Object Type: Report
System: The UNT Digital Library
THERMAL EVALUATION OF THE 2-MCO/2-DHLW WASTE PACKAGE (open access)

THERMAL EVALUATION OF THE 2-MCO/2-DHLW WASTE PACKAGE

The objective of this calculation was to determine the structural response of multi-canister overpacks (MCO) and the 2-MCO/2-Defense High-Level Waste (DHLW) Waste Package (WP) subjected to tip-over onto an unyielding surface (US). The scope of this calculation was limited to reporting the calculation results in terms of maximum stress intensities. This calculation is associated with the waste package design and was performed by the Waste Package Design Section in accordance with the DOE SNF Analysis Plan for FY 2000.
Date: July 5, 2000
Creator: Schmitt, T.
Object Type: Report
System: The UNT Digital Library
D0 General Support: The Use of Programmable Logic Controllers (PLCS) at D0 (open access)

D0 General Support: The Use of Programmable Logic Controllers (PLCS) at D0

With the exception of control of heating, ventilation, and air conditioning (HVAC) ventilation fans, and their shutdown in the case of smoke in the ducts, all implementations of Programmable Logic Controllers (PLCs) in Dzero have been made within the fundamental premise that no uncertified PLC apparatus shall be entrusted with the safety of equipment or personnel. Thus although PLCs are used to control and monitor all manner of intricate equipment, simple hardware interlocks and relief devices provide basic protection against component failure, control failure, or inappropriate control operation. Nevertheless, this report includes two observations as follows: (1) It may be prudent to reconfigure the link between the Pyrotronics system and the HVAC system such that the Pyrotronics system provides interlocks to the ventilation fans instead of control inputs to the uncertified HVAC PLCs. Although the Pyrotronics system is certified and maintained to life safety standards, the HVAC system is not. A hardware or software failure of the HVAC system probably should not be allowed to result in the situation where the ventilation fans in a smoke filled duct continue to operate. Dan Markley is investigating this matter. (2) It may also be prudent to examine the network security of those …
Date: May 5, 2000
Creator: Hance, R.
Object Type: Report
System: The UNT Digital Library
The structure of the alpha-Al2O3(0001) surface from low-energyelectron diffraction: Al termination and evidence for large thermalvibrations (open access)

The structure of the alpha-Al2O3(0001) surface from low-energyelectron diffraction: Al termination and evidence for large thermalvibrations

We have determined the surface structure of alpha-Al2O3(0001) using dynamical low-energy electron diffraction (LEED). Sapphire surfaces were prepared in three different ways, and the diffraction results were analyzed using an exhaustive search of possible models. For all sample processing conditions, the clearly favored structure has a single Al layer termination and a large first interlayer contraction. In addition, we find that the surface atoms have unusually large vibrational amplitudes at room temperature, suggestive of an anharmonic vibrational mode.
Date: May 5, 2000
Creator: Soares, E. A.; Van Hove, M. A.; Walters, C. F. & McCarty, K. F.
Object Type: Article
System: The UNT Digital Library
Shallow Cavity Flow Tone Experiments: Onset of Locked-On States (open access)

Shallow Cavity Flow Tone Experiments: Onset of Locked-On States

Fully turbulent inflow past a shallow cavity is investigated for the configuration of an axisymmetric cavity mounted in a pipe. Emphasis is on conditions giving rise to coherent oscillations, which can lead to locked-on states of flow tones in the pipe-cavity system. Unsteady surface pressure measurements are interpreted using three-dimensional representations of amplitude-frequency-inflow velocity; these representations are constructed for a range of cavity depth. Assessment of these data involves a variety of approaches. Evaluation of pressure gradients on plan views of the three-dimensional representations allows extraction of the frequencies of the instability (Strouhal) modes of the cavity oscillation. These frequency components are correlated with traditional models originally formulated for cavities in a free-stream. In addition, they are normalized using two length scales; inflow boundary-layer thickness and pipe diameter. These scales are consistent with those employed for the hydrodynamic instability of the separated shear layer, and are linked to the large-scale mode of the shear layer oscillation, which occurs at relatively long cavity length. In fact, a simple scaling based on pipe diameter can correlate the frequencies of the dominant peaks over a range of cavity depth. The foregoing considerations provide evidence that pronounced flow tones can be generated from a …
Date: September 5, 2000
Creator: Rockwell, D.; Lin, J. C.; Oshkai, P.; Reiss, M. & Pollack, M.
Object Type: Report
System: The UNT Digital Library
METHANE de-NOX FOR UTILITY PC BOILERS (open access)

METHANE de-NOX FOR UTILITY PC BOILERS

The overall project objective is the development and validation of an innovative combustion system, based on a novel coal preheating concept prior to combustion, that can reduce NO{sub x} emissions to 0.15 lb/million Btu or less on utility pulverized coal (PC) boilers. This NO{sub x} reduction should be achieved without loss of boiler efficiency or operating stability, and at more than 25% lower levelized cost than state-of-the-art SCR technology. A further objective is to make this technology ready for full-scale commercial deployment by 2002-2003 in order to meet an anticipated market demand for NO{sub x} reduction technologies resulting from the EPA's NO{sub x} SIP call.
Date: July 5, 2000
Creator: Rabovitser, Joseph
Object Type: Report
System: The UNT Digital Library
The KM phase in semi-realistic heterotic orbifold models (open access)

The KM phase in semi-realistic heterotic orbifold models

In string-inspired semi-realistic heterotic orbifolds models with an anomalous U(1){sub X},a nonzero Kobayashi-Masakawa (KM) phase is shown to arise generically from the expectation values of complex scalar fields, which appear in nonrenormalizable quark mass couplings. Modular covariant nonrenormalizable superpotential couplings are constructed. A toy Z{sub 3} orbifold model is analyzed in some detail. Modular symmetries and orbifold selection rules are taken into account and do not lead to a cancellation of the KM phase. We also discuss attempts to obtain the KM phase solely from renormalizable interactions.
Date: July 5, 2000
Creator: Giedt, Joel
Object Type: Article
System: The UNT Digital Library
Emplacement Ventilation System (open access)

Emplacement Ventilation System

The purpose of this analysis is to identify conceptual design options for the emplacement ventilation system, specifically within the emplacement drifts. The designs are based on the Enhanced Design Alternative (EDA) II concept developed during the license application design selection exercise as described in the ''License Application Design Selection Report'' (CRWMS M&amp;O 1999a) and in the emplacement drift ''Ventilation Model'' (CRWMS M&amp;O 2000c). The scope of this analysis, as outlined in the development plan (CRWMS M&amp;O 2000a), includes the following tasks: (1) Description of the air flow path in the emplacement drifts. (2) Examination of the exhaust options for air exiting the emplacement drifts. (3) Examination of the air control options in the emplacement drifts. (4) Discussion of following system components and structures: emplacement isolation doors, portable shadow shield and exhaust main partition. The objective of this analysis is to support site recommendation through input to the system description documents. Off-normal conditions are not discussed in this analysis.
Date: April 5, 2000
Creator: Vance, R.
Object Type: Report
System: The UNT Digital Library
Waste Feed Delivery Transfer System Analysis (open access)

Waste Feed Delivery Transfer System Analysis

This document provides a documented basis for the required design pressure rating and pump pressure capacity of the Hanford Site waste-transfer system in support of the waste feed delivery to the privatization contractor for vitrification. The scope of the analysis includes the 200 East Area double-shell tank waste transfer pipeline system and the associated transfer system pumps for a11 Phase 1B and Phase 2 waste transfers from AN, AP, AW, AY, and A2 Tank Farms.
Date: May 5, 2000
Creator: Julyk, L. J.
Object Type: Report
System: The UNT Digital Library
Availability Analysis of the Ventilation Stack CAM Interlock System (open access)

Availability Analysis of the Ventilation Stack CAM Interlock System

Ventilation Stack Continuous Air Monitor (CAM) Interlock System failure modes, failure frequencies and system availability have been evaluated for the RPP. The evaluation concludes that CAM availability is as high as assumed in the safety analysis and that the current routine system surveillance is adequate to maintain this availability. Further, requiring an alarm to actuate upon CAM failure is not necessary to maintain the availability credited in the safety analysis, nor is such an arrangement predicted to significantly improve system availability. However, if CAM failures were only detected by the 92-day functional tests required in the Authorization Basis (AB), CAM availability would be much less than that credited in the safety analysis. Therefore it is recommended that the current surveillance practice of daily simple system checks, 30-day source checks and 92-day functional tests be continued in order to maintain CAM availability.
Date: January 5, 2000
Creator: YOUNG, J.
Object Type: Report
System: The UNT Digital Library
Cold Vacuum Drying Instrument Air System Design Description (SYS 12) (open access)

Cold Vacuum Drying Instrument Air System Design Description (SYS 12)

This system design description (SDD) addresses the instrument air (IA) system of the spent nuclear fuel (SNF). This IA system provides instrument quality air to the Cold Vacuum Drying (CVD) Facility. The IA system is a general service system that supports the operation of the heating, ventilation, and air conditioning (HVAC) system, the process equipment skids, and process instruments in the CVD Facility. The following discussion is limited to the compressor, dryer, piping, and valving that provide the IA as shown in Drawings H-1-82222, Cold Vacuum Drying Facility Mechanical Utilities Compressed & Instrument Air P&amp;ID, and H-1.82161, Cold Vacuum Drying Facility Process Equipment Skid P&amp;ID MCO/Cusk Interface. Figure 1-1 shows the physical location of the 1A system in the CVD Facility.
Date: June 5, 2000
Creator: Shapley, B. J. & Tran, Y. S.
Object Type: Report
System: The UNT Digital Library
105-K Basin Material Design Basis Feed Description for Spent Nuclear Fuel (SNF) Project Facilities VOL 2 Sludge (open access)

105-K Basin Material Design Basis Feed Description for Spent Nuclear Fuel (SNF) Project Facilities VOL 2 Sludge

Volume 2 provides estimated chemical and radionuclide inventories of sludge currently stored within the Hanford Site's 105-K Basin This volume also provides estimated chemical and radionuclide inventories for the sludge streams expected to be generated during Spent Nuclear Fuel (SNF) Project activities.
Date: April 5, 2000
Creator: PEARCE, K.L.
Object Type: Report
System: The UNT Digital Library
Parametric Analyses of Heat Removal from High Level Waste Tanks (open access)

Parametric Analyses of Heat Removal from High Level Waste Tanks

The general thermal hydraulics program GOTH-SNF was used to predict the thermal response of the waste in tanks 241-AY-102 and 241-AZ-102 when mixed by two 300 horsepower mixer pumps. This mixing was defined in terms of a specific waste retrieval scenario. Both dome and annulus ventilation system flow are necessary to maintain the waste within temperature control limits during the mixing operation and later during the sludge-settling portion of the scenario are defined.
Date: June 5, 2000
Creator: Truitt, J. B.
Object Type: Report
System: The UNT Digital Library