SINGLE CRYSTAL NEUTRON DIFFRACTION. (open access)

SINGLE CRYSTAL NEUTRON DIFFRACTION.

Single-crystal neutron diffraction measures the elastic Bragg reflection intensities from crystals of a material, the structure of which is the subject of investigation. A single crystal is placed in a beam of neutrons produced at a nuclear reactor or at a proton accelerator-based spallation source. Single-crystal diffraction measurements are commonly made at thermal neutron beam energies, which correspond to neutron wavelengths in the neighborhood of 1 Angstrom. For high-resolution studies requiring shorter wavelengths (ca. 0.3-0.8 Angstroms), a pulsed spallation source or a high-temperature moderator (a ''hot source'') at a reactor may be used. When complex structures with large unit-cell repeats are under investigation, as is the case in structural biology, a cryogenic-temperature moderator (a ''cold source'') may be employed to obtain longer neutron wavelengths (ca. 4-10 Angstroms). A single-crystal neutron diffraction analysis will determine the crystal structure of the material, typically including its unit cell and space group, the positions of the atomic nuclei and their mean-square displacements, and relevant site occupancies. Because the neutron possesses a magnetic moment, the magnetic structure of the material can be determined as well, from the magnetic contribution to the Bragg intensities. This latter aspect falls beyond the scope of the present unit; for …
Date: March 13, 2001
Creator: Koetzle, T. F.
Object Type: Book
System: The UNT Digital Library
Monitoring the Ocean Acoustic Environment: A Model-Based Detection Approach (open access)

Monitoring the Ocean Acoustic Environment: A Model-Based Detection Approach

A model-based approach is applied in the development of a processor designed to passively monitor an ocean acoustic environment along with its associated variations. The technique employs an adaptive, model-based processor embedded in a sequential likelihood detection scheme. The trade-off between state-based and innovations-based monitor designs is discussed, conceptually. The underlying theory for the innovations-based design is briefly developed and applied to a simulated data set.
Date: March 13, 2000
Creator: Candy, J. V. & Sullivan, E. J.
Object Type: Article
System: The UNT Digital Library
Nucleic Acid-Based Detection and Identification of Bacterial and Fungal Plant Pathogens - Final Report (open access)

Nucleic Acid-Based Detection and Identification of Bacterial and Fungal Plant Pathogens - Final Report

The threat to American interests from terrorists is not limited to attacks against humans. Terrorists might seek to inflict damage to the U.S. economy by attacking our agricultural sector. Infection of commodity crops by bacterial or fungal crop pathogens could adversely impact U.S. agriculture, either directly from damage to crops or indirectly from damage to our ability to export crops suspected of contamination. Recognizing a terrorist attack against U.S. agriculture, to be able to prosecute the terrorists, is among the responsibilities of the members of Hazardous Material Response Unit (HMRU) of the Federal Bureau of Investigation (FBI). Nucleic acid analysis of plant pathogen strains by the use of polymerase chain reaction (PCR) amplification techniques is a powerful method for determining the exact identity of pathogens, as well as their possible region of origin. This type of analysis, however, requires that PCR assays be developed specific to each particular pathogen strain, an d analysis protocols developed that are specific to the particular instrument used for detection. The objectives of the work described here were threefold: (1) to assess the potential terrorist threat to U.S. agricultural crops, (2) to determine whether suitable assays exist to monitor that threat, and (3) where assays …
Date: March 13, 2001
Creator: Kingsley, Mark T
Object Type: Report
System: The UNT Digital Library
Silo 3 Waste Treatment Phase I Physical Testing Final Report (open access)

Silo 3 Waste Treatment Phase I Physical Testing Final Report

A characterization study of the Fernald Silo 3 waste was performed at the request of Rocky Mountain Remedial Services, LLC (RMRS) to support treatment of the waste with the Envirobond reagents and Envirobrick process. The Savannah River Technology Center (SRTC) performed the characterization under a Work for Others Agreement WOF-00-007. Physical property testing was subcontracted to the Clemson Environmental Technologies Laboratory (CETL). This report is intended to transmit the results of the physical property testing conducted at the CETL. Results of the physical property testing are summarized in a final report from Steve Hoeffner, CETL.
Date: March 13, 2001
Creator: Langton, C. A.
Object Type: Report
System: The UNT Digital Library
SINGLE CRYSTAL NEUTRON DIFFRACTION. (open access)

SINGLE CRYSTAL NEUTRON DIFFRACTION.

Single-crystal neutron diffraction measures the elastic Bragg reflection intensities from crystals of a material, the structure of which is the subject of investigation. A single crystal is placed in a beam of neutrons produced at a nuclear reactor or at a proton accelerator-based spallation source. Single-crystal diffraction measurements are commonly made at thermal neutron beam energies, which correspond to neutron wavelengths in the neighborhood of 1 Angstrom. For high-resolution studies requiring shorter wavelengths (ca. 0.3-0.8 Angstroms), a pulsed spallation source or a high-temperature moderator (a ''hot source'') at a reactor may be used. When complex structures with large unit-cell repeats are under investigation, as is the case in structural biology, a cryogenic-temperature moderator (a ''cold source'') may be employed to obtain longer neutron wavelengths (ca. 4-10 Angstroms). A single-crystal neutron diffraction analysis will determine the crystal structure of the material, typically including its unit cell and space group, the positions of the atomic nuclei and their mean-square displacements, and relevant site occupancies. Because the neutron possesses a magnetic moment, the magnetic structure of the material can be determined as well, from the magnetic contribution to the Bragg intensities. This latter aspect falls beyond the scope of the present unit; for …
Date: March 13, 2001
Creator: Koetzle, T. F.
Object Type: Book
System: The UNT Digital Library
Introduction to the Theory and Analysis of Resolved (and Unresolved) Neutron Resonances via SAMMY (open access)

Introduction to the Theory and Analysis of Resolved (and Unresolved) Neutron Resonances via SAMMY

Neutron cross-section data are important for two purposes: First, they provide insight into the nature of matter, increasing our understanding of fundamental physics. Second, they are needed for practical applications (e.g., for calculating when and how a reactor will become critical, or how much shielding is needed for storage of nuclear materials, or for medical applications). Neutron cross section data in the resolved-resonance region are generally obtained by time-of-flight experiments, which must be carefully analyzed if they are to be properly understood and utilized. In this report, important features of the analysis process are discussed, with emphasis on the particular techniques used in the analysis code SAMMY. Other features of the code are also described; these include such topics as calculation of group cross sections (including covariance matrices), generation and fitting of integral quantities, and extensions into the unresolved-resonance region and higher-energy regions.
Date: March 13, 2000
Creator: Larson, N.
Object Type: Article
System: The UNT Digital Library
Soil Vapor Extraction Testing of Selected Wells in the Northern Sector of A-Area (open access)

Soil Vapor Extraction Testing of Selected Wells in the Northern Sector of A-Area

The purpose of this testing was to determine if a vadose zone source for the contamination remains and to begin collecting data to assist with determining the location of any significant source.
Date: March 13, 2001
Creator: Dixon, K.L.
Object Type: Report
System: The UNT Digital Library
CHARACTERIZATION OF AIRFLOWS NEAR THE EXIT OF HVAC REGISTERS USING LASER DOPPLER VELOCIMETRY (LDV). (open access)

CHARACTERIZATION OF AIRFLOWS NEAR THE EXIT OF HVAC REGISTERS USING LASER DOPPLER VELOCIMETRY (LDV).

A facility to characterize the airflow at the exit of HVAC registers was designed and fabricated. The objective of this work is to obtain velocity and turbulence data at the exit of registers, which can then be used as an input boundary condition in a modern Computational Fluid Dynamics (CFD) code to predict the velocity and temperature distribution in an enclosure, and also the register performance parameters such as throw. During the course of this work, two commonly used registers were tested. Both registers were 8 inch x 4 inch sidewall registers. Laser Doppler Velocimetry was used to measure the axial and vertical components of the velocity vector at various locations across the face of the registers. For the two cases of registers studied here, the results suggest that the velocity field at the very exit of each of these registers scales with the flow rate through the registers. This means that, in the mode of operation in which the supply fan (of an HVAC system) has a ''High'' and ''Low'' setting, similar velocity scaling would result for the type of registers tested here.
Date: March 13, 2003
Creator: Tutu, N. K.; Krishna, C. R.; Andrews, J. W. & Butcher, T. A.
Object Type: Report
System: The UNT Digital Library
Hybrid electric vehicle technology assessment : methodology, analytical issues, and interim results. (open access)

Hybrid electric vehicle technology assessment : methodology, analytical issues, and interim results.

This report presents the results of the first phase of Argonne National Laboratory's (ANL's) examination of the costs and energy impacts of light-duty hybrid electric vehicles (HEVs). We call this research an HEV Technology Assessment, or HEVTA. HEVs are vehicles with drivetrains that combine electric drive components (electric motor, electricity storage) with a refuelable power plant (e.g., an internal combustion engine). The use of hybrid drivetrains is widely considered a key technology strategy in improving automotive fuel efficiency. Two hybrid vehicles--Toyota's Prius and Honda's Insight--have been introduced into the U.S. market, and all three auto industry participants in the Partnership for a New Generation of Vehicles (PNGV) have selected hybrid drivetrains for their prototype vehicles.
Date: March 13, 2002
Creator: Plotkin, S.; Santini, D.; Vyas, A.; Anderson, J.; Wang, M.; Bharathan, D. et al.
Object Type: Report
System: The UNT Digital Library
Review and Prioritization of Technical Issues Related to Burnup Credit for LWR Fuel (open access)

Review and Prioritization of Technical Issues Related to Burnup Credit for LWR Fuel

This report has been prepared to review relevant background information and provide technical discussion that will help initiate a PIRT (Phenomena Identification and Ranking Tables) process for use of burnup credit in light-water reactor (LWR) spent fuel storage and transport cask applications. The PIRT process will be used by the NRC Office of Nuclear Regulatory Research to help prioritize and guide a coordinated program of research and as a means to obtain input/feedback from industry and other interested parties. The review and discussion in this report are based on knowledge and experience gained from work performed in the United States and other countries. Current regulatory practice and perceived industry needs are also reviewed as a background for prioritizing technical needs that will facilitate safe practice in the use of burnup credit. Relevant physics and analysis phenomenon are identified, and an assessment of their importance to burnup credit implementation is given. Finally, phenomena that need to be better understood for effective licensing, together with technical issues that require resolution, are presented and discussed in the form of a prioritization ranking and initial draft program plan.
Date: March 13, 2000
Creator: Parks, C. V.
Object Type: Report
System: The UNT Digital Library
MOX FUEL PIN MEASURING APPARATUS (open access)

MOX FUEL PIN MEASURING APPARATUS

This report summarizes the design of the ATR MOX Test Fuel Pin Measuring Device. This device makes use of four Magnescale probes and a precision sliding table to make three-dimensional measurements of a short fuel pin (approximately 8 inches) with an accuracy of better than 0.0003 inches. Mathematical fitting is then used to determine the diameter and bowing of the fuel pin as a function of length. This device is currently being applied to fuel pins irradiated in the Advanced Test Reactor (ATR) as part of the Light Water Mixed Oxide Fuel Irradiation Test sponsored by the Department of Energy.
Date: March 13, 2001
Creator: MORRIS, R.N.
Object Type: Report
System: The UNT Digital Library
Study of metal dusting phenomenon and development of materials resistant to metal dusting. (open access)

Study of metal dusting phenomenon and development of materials resistant to metal dusting.

The deposition of carbon from carbonaceous gaseous environments is prevalent in many chemical and petrochemical processes such as reforming systems, syngas production systems, iron reduction plants, and others. One of the major consequences of carbon deposition is the degradation of structural materials by a phenomenon known as metal dusting. There are two major issues of importance in metal dusting. First is formation of carbon and subsequent deposition of carbon on metallic materials. Second is the initiation of metal dusting degradation of the alloy. Details are presented on a research program that is underway at Argonne National Laboratory to study the metal dusting phenomenon from a fundamental scientific base involving laboratory research in simulated process conditions and field testing of materials in actual process environments. The project has participation from the US chemical industry, alloy manufacturers, and the Materials Technology Institute, which serves the chemical process industry.
Date: March 13, 2002
Creator: Natesan, K.
Object Type: Report
System: The UNT Digital Library
Subsurface Conditions Description of the B and BX and BY Waste Management Area (open access)

Subsurface Conditions Description of the B and BX and BY Waste Management Area

This document provides a discussion of the subsurface conditions relevant to the occurrence and migration of contaminants in the vadose zone and groundwater underlying the 241-B, -BX, and -BY tank farms. This document provides a concise summary of existing information in support of characterization planning. This document includes a description of the available environmental contamination data and a limited, qualitative interpretation of these data.
Date: March 13, 2000
Creator: WOOD, M.I.
Object Type: Report
System: The UNT Digital Library
Determination of free hole concentration in ferromagnetic Ga(1-x)MnxAs using electrochemical capacitance-voltage profiling (open access)

Determination of free hole concentration in ferromagnetic Ga(1-x)MnxAs using electrochemical capacitance-voltage profiling

None
Date: March 13, 2002
Creator: Yu, K.M.; Walukiewicz, W.; Wojtowicz, T.; Lim, W.L.; Liu, X.; Sasaki, Y. et al.
Object Type: Article
System: The UNT Digital Library
Magnetic Propulsion of Intense Lithium Streams in a Tokamak Magnetic Field (open access)

Magnetic Propulsion of Intense Lithium Streams in a Tokamak Magnetic Field

The paper gives the theory of magnetic propulsion of liquid lithium streams and their stability in tokamaks. In the approximation of a thin flowing layer the MHD equations are reduced to one integro-differential equation which takes into account the propulsion effect, viscosity and the drag force due to magnetic pumping and other interactions with the magnetic field. A criterion is obtained for the stabilization of the ''sausage'' instability of the streams by centrifugal force.
Date: March 13, 2002
Creator: Zakharov, Leonid E.
Object Type: Report
System: The UNT Digital Library
PUREX Waste Stabilization (open access)

PUREX Waste Stabilization

This report summarizes the results of a feasibility study that evaluated solidification as an alternative treatment for organic waste.
Date: March 13, 2002
Creator: Langston, C.A.
Object Type: Report
System: The UNT Digital Library
Migrating birds : assessment of impact on 915-MHz radar wind profiler performance at the Atmospheric Radiation Measurement Program's southern great plains. (open access)

Migrating birds : assessment of impact on 915-MHz radar wind profiler performance at the Atmospheric Radiation Measurement Program's southern great plains.

The U. S. Department of Energy's Atmospheric Radiation Measurement Program is running a small network of 915-MHz radar wind profilers (RWPs) at its Southern Great Plains Cloud and Radiation Testbed site in northern Oklahoma and southern Kansas. Seasonal migration of passerines may cause significant interference with the operation of 915-MHz RWPs. The extent of this ''bird jamming'' depends on the radar's parameters, the place of deployment, the season, and the time of day. This poster presents a new diagnostic method for detecting possible bird contamination in RWP data, along with an evaluation of the method using a three-year data set for two RWPs.
Date: March 13, 2002
Creator: Pekour, M. S.
Object Type: Article
System: The UNT Digital Library
Using Arrested Solid-Solid Multiphase Reactions in Geological Materials to Deduce the Rate of Crustal Uplift (open access)

Using Arrested Solid-Solid Multiphase Reactions in Geological Materials to Deduce the Rate of Crustal Uplift

The history geological terrains experience can be traced as a series of temperature and pressure changes. Each change drives the system toward a new state of thermodynamic equilibrium. The resultant overprinted rock fabrics, textures and chemical heterogeneities can be difficult to interpret. However, if carefully chosen, features from the scale of kilometers to nanometers can be used to reconstruct the history of mountain systems. Uplift of the Sri Lankan Central Highlands was rapid enough to preserve well-developed symplectite textures, some of which represent arrested solid-state diffusion-controlled reactions of garnet + O{sub 2} to form orthopyroxene + plagioclase + magnetite, as the rocks were exhumed from over 30 km in the earth's crust. Our objective has been to determine the reaction mechanisms responsible for symplectite development, and to establish the time interval over which these reactions occurred, to constrain the rate of mountain uplift. Considering that the most rapid mechanism is solid state grain-boundary diffusion of oxygen, the reaction time can be constrained by bounding the rate of oxygen supply to the reaction site. The solid state grain boundary diffusion rate of oxygen has been inferred to be ca. 10{sup -14}m{sup 2}-sec (Farver and Yund, 1991), but is sensitive to inferred …
Date: March 13, 2000
Creator: Glassley, W.E. & Meike, A.
Object Type: Article
System: The UNT Digital Library
Calibration Report for the WRAP Facility Gamma Energy Analysis System (104-ND-06-102A) (open access)

Calibration Report for the WRAP Facility Gamma Energy Analysis System (104-ND-06-102A)

The Waste Receiving And Processing facility (WRAP) adheres to providing gamma-ray spectroscopy instrument calibrations traceable to the National Institute for Standards and Technology (NIST) standard{sup (4)}. The detectors are used to produce quantitative results for the Waste Isolation Pilot Plant (WIPP) and must meet calibration programmatic calibration goals. Instruments must meet portions of ANSI N42.14, 1978 guide for Germanium detectors. The Non-Destructive Assay (NDA) Gamma Energy Analysis (GEA) utilizes NIST traceable line source standards for the detector system calibrations. The counting configuration is a series of drums containing the line sources and different density filler matrices. The drums are used to develop system efficiencies with respect to density. The efficiency and density correction factors are required for the processing of drummed waste materials of similar densities. The calibration verification is carried out after the calibration is deemed final, by counting a second drum of NIST traceable sources. Three in-depth calibrations have been completed on one of the two systems to date, the first being the system acceptance plan. This report has a secondary function; that being the development of the instrument calibration errors which are to be folded into the Total Instrument Uncertainty document, HNF-4050.
Date: March 13, 2000
Creator: WILLS, C.E.
Object Type: Report
System: The UNT Digital Library
High temperature oxidation of irradiated Limerick BWR cladding. (open access)

High temperature oxidation of irradiated Limerick BWR cladding.

None
Date: March 13, 2002
Creator: Yan, Y.; Strain, R. V.; Bray, T. S. & Billone, M. C.
Object Type: Article
System: The UNT Digital Library
Waste Receiving and Processing (WRAP) Facility Weight Scale Analysis Fairbanks Weight Scale Evaluation Results (open access)

Waste Receiving and Processing (WRAP) Facility Weight Scale Analysis Fairbanks Weight Scale Evaluation Results

Fairbanks Weight Scales are used at the Waste Receiving and Processing (WRAP) facility to determine the weight of waste drums as they are received, processed, and shipped. Due to recent problems, discovered during calibration, the WRAP Engineering Department has completed this document which outlines both the investigation of the infeed conveyor scale failure in September of 1999 and recommendations for calibration procedure modifications designed to correct deficiencies in the current procedures.
Date: March 13, 2000
Creator: Johnson, M. D.
Object Type: Report
System: The UNT Digital Library
Spent Nuclear Fuel (SNF) Process Validation Technical Support Plan (open access)

Spent Nuclear Fuel (SNF) Process Validation Technical Support Plan

The purpose of Process Validation is to confirm that nominal process operations are consistent with the expected process envelope. The Process Validation activities described in this document are not part of the safety basis, but are expected to demonstrate that the process operates well within the safety basis. Some adjustments to the process may be made as a result of information gathered in Process Validation.
Date: March 13, 2000
Creator: SEXTON, R.A.
Object Type: Report
System: The UNT Digital Library
Progress Report: DE-FG03-97ER20274, ''Microbial Production of Isoprene'' (open access)

Progress Report: DE-FG03-97ER20274, ''Microbial Production of Isoprene''

We have discovered that microorganisms produce and emit the hydrocarbon isoprene (2-methyl-1,3-butadiene), and have suggested that if isoprene-producing enzymes and their genes can be harnessed, useful hydrocarbon-producing systems might be constructed. The main goal of the proposed work is to establish the biochemical mechanism and regulation of isoprene formation in the bacterial system, Bacillus subtilis. Specific objectives of the proposed work are the following: (A) to characterize the physiological regulation of isoprene formation in B. subtilis; (B) to characterize mutations in B. subtilis 168 that suppress isoprene formation, clone these genes, and determine how isoprene and isoprenoid carbon flow are regulated; and (C) to test ''overflow'' and ''signaling'' models for Bacillus isoprene formation. We are also pursuing the isolation and cloning of B. subtilis isoprene synthase, which we believe may be a regulatory enzyme.
Date: March 13, 2002
Creator: Fall, Ray
Object Type: Report
System: The UNT Digital Library
Acceptance for Beneficial Use Pumping Instrumentation and Control Skid N (open access)

Acceptance for Beneficial Use Pumping Instrumentation and Control Skid N

This is a final Acceptance for Beneficial Use (ABU) for Pumping and Instrumentation Control (PIC) skid ''N''. PIC skid ''N'' is ready for pumping tank U-109. All the testing and documentation has been completed as required on the AE3U checklist. This AE3U covers only the readiness of the PIC skid ''N''. Other U-farm preparations including dilution tank fabrication, portable exhauster readiness, leak detection, valve pit preparation, and the Operation Control Station readiness are not part of this ABU. PIC skid ''N'' is a new skid fabricated and tested at Site Fabrication Services. The skid controls the jet pump and monitors various instruments associated with the pumping operation. This monitoring includes leak detection along the waste transfer route and flammable gases in the pump pit. This Acceptance for Beneficial Use documents that Pumping Instrumentation and Control (PIC) skid ''N'' is ready for field use. This document does not cover the field installation or operational testing.
Date: March 13, 2000
Creator: Koch, M. R.
Object Type: Report
System: The UNT Digital Library