Resource Type

National Radiobiology Archives Distributed Access User's Manual, Version 1. 1 (open access)

National Radiobiology Archives Distributed Access User's Manual, Version 1. 1

This supplement to the NRA Distributed Access User's manual (PNL-7877), November 1991, describes installation and use of Version 1.1 of the software package; this is not a replacement of the previous manual. Version 1.1 of the NRA Distributed Access Package is a maintenance release. It eliminates several bugs, and includes a few new features which are described in this manual. Although the appearance of some menu screens has changed, we are confident that the Version 1.0 User's Manual will provide an adequate introduction to the system. Users who are unfamiliar with Version 1.0 may wish to experiment with that version before moving on to Version 1.1.
Date: June 1, 1992
Creator: Smith, S. K.; Prather, J. C.; Ligotke, E. K. & Watson, C. R.
System: The UNT Digital Library
National Radiobiology Archives Distributed Access User`s Manual, Version 1.1. Revision 1 (open access)

National Radiobiology Archives Distributed Access User`s Manual, Version 1.1. Revision 1

This supplement to the NRA Distributed Access User`s manual (PNL-7877), November 1991, describes installation and use of Version 1.1 of the software package; this is not a replacement of the previous manual. Version 1.1 of the NRA Distributed Access Package is a maintenance release. It eliminates several bugs, and includes a few new features which are described in this manual. Although the appearance of some menu screens has changed, we are confident that the Version 1.0 User`s Manual will provide an adequate introduction to the system. Users who are unfamiliar with Version 1.0 may wish to experiment with that version before moving on to Version 1.1.
Date: June 1, 1992
Creator: Smith, S. K.; Prather, J. C.; Ligotke, E. K. & Watson, C. R.
System: The UNT Digital Library
Quantifying Silica Reactivity in Subsurface Environments: An Integrated Experimental Study of Quartz and Amorphous Silica to Establish a Baseline for Glass Durability (open access)

Quantifying Silica Reactivity in Subsurface Environments: An Integrated Experimental Study of Quartz and Amorphous Silica to Establish a Baseline for Glass Durability

An immediate EM science need is a reliable kinetic model that predicts long-term waste glass performance. A framework for which the kinetics of mineral-solution reactions can be used to interpret complex silicate glass properties is required to accurately describe the current and future behavior of glasses as synthetic monoliths or natural analogs. Reaction rates and mechanisms are essential elements in deciphering mineral/material reactivity trends within a compositional series or across a matrix of complex solution compositions. An essential place to start, and the goal of this research, is to quantify the reactivity of crystalline and amorphous SiO2 phases in the complex fluids of natural systems.
Date: June 10, 2003
Creator: Dove, Patricia
System: The UNT Digital Library
Quantifying Silica Reactivity in Subsurface Environments: An Integrated Experimental Study of Quartz and Amorphous Silica to Establish a Baseline for Glass Durability (open access)

Quantifying Silica Reactivity in Subsurface Environments: An Integrated Experimental Study of Quartz and Amorphous Silica to Establish a Baseline for Glass Durability

An immediate EM science need is a reliable kinetic model that predicts long-term waste glass performance. A framework for which the kinetics of mineral-solution reactions can be used to interpret complex silicate glass properties is required to accurately describe the current and future behavior of glasses as synthetic monoliths or natural analogs. Reaction rates and mechanisms are essential elements in deciphering mineral/material reactivity trends within a compositional series or across a matrix of complex solution compositions. An essential place to start, and the goal of this research, is to quantify the reactivity of crystalline and amorphous SiO2 phases in the complex fluids of natural systems.
Date: June 15, 2001
Creator: Dove, Patricia M.
System: The UNT Digital Library
24-Channel Geophone Array for Horizontal or Vertical Boreholes Quarterly Technical Report: January-March 2003 (open access)

24-Channel Geophone Array for Horizontal or Vertical Boreholes Quarterly Technical Report: January-March 2003

This report describes the technical progress on a project to design and construct a multichannel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the method for clamping the sensor once it is emplaced in the borehole. If the sensors (geophones) are not adequately coupled to the surrounding rock mass, the resulting data will be of very poor quality. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date: June 1, 2003
Creator: Westman, Erik C.
System: The UNT Digital Library
Control of pyrite surface chemistry in physical coal cleaning. Second quarterly progress report, December 1, 1989--February 28, 1990 (open access)

Control of pyrite surface chemistry in physical coal cleaning. Second quarterly progress report, December 1, 1989--February 28, 1990

To better understand the surface chemical properties of coal and mineral pyrite, studies on the effect of flotation surfactants (frother and kerosene) on the degree of hydrophobicity have been conducted. The presence of either frother or kerosene enhanced the flotability of coal and mineral pyrite with a corresponding decrease in induction time over the pH range examined. Scanning electron microscopy (SEM) results indicate a correlation exists between the sample surface morphology and crystal structure and the observed hydrophobicity. As a result of the data obtained from the surface characterization studies, controlled surface oxidation was investigated as a possible pyrite rejection scheme in microbubble column flotation.
Date: June 24, 1992
Creator: Luttrell, G. H.; Yoon, R. H.; Zachwieja, J. & Lagno, M.
System: The UNT Digital Library
Control of pyrite surface chemistry in physical coal cleaning. Seventh quarterly progress report, March 1, 1991--May 31, 1991 (open access)

Control of pyrite surface chemistry in physical coal cleaning. Seventh quarterly progress report, March 1, 1991--May 31, 1991

The removal of pyrite from coal by flotation or any other surface chemistry based separation process is often hampered by the apparent hydrophobicity of the mineral. Results obtained in this project suggest that corrosion processes are responsible for the apparent hydrophobicity of pyrite in aqueous environments. Characterization of the corrosion products of pyrite in acidic and alkaline solution has been performed using electrochemical (cyclic voltammetry and single-potential-step chronoamperometry) and spectroscopic techniques (X-ray photoelectron spectroscopy -- XPS). The nature of the surface products have been correlated with hydrophobicity determined from in-situ contact angle measurements. The results show that pyrite hydrophobicity is influenced by either the oxidation or reduction conditions of the system.
Date: June 24, 1992
Creator: Luttrell, G. H.; Yoon, R. H. & Zachwieja, J. B.
System: The UNT Digital Library
Control of pyrite surface chemistry in physical coal cleaning (open access)

Control of pyrite surface chemistry in physical coal cleaning

The removal of pyrite from coal by flotation or any other surface chemistry based separation process is often hampered by the apparent hydrophobicity of the mineral. Results obtained in this project suggest that corrosion processes are responsible for the apparent hydrophobicity of pyrite in aqueous environments. Characterization of the corrosion products of pyrite in acidic and alkaline solution has been performed using electrochemical (cyclic voltammetry and single-potential-step chronoamperometry) and spectroscopic techniques (X-ray photoelectron spectroscopy -- XPS). The nature of the surface products have been correlated with hydrophobicity determined from in-situ contact angle measurements. The results show that pyrite hydrophobicity is influenced by either the oxidation or reduction conditions of the system.
Date: June 24, 1992
Creator: Luttrell, G. H.; Yoon, R. H. & Zachwieja, J. B.
System: The UNT Digital Library
Control of pyrite surface chemistry in physical coal cleaning (open access)

Control of pyrite surface chemistry in physical coal cleaning

The successful separation of pyrite from coal by flotation is dependent to a large extent upon the selectivity of the process, and the use of a pyrite depressant is one of the most important and cost-effective techniques for achieving this. This report evaluates the effects of three factors on the floatability of pyrite. These are (1) the superficial oxidation of pyrite, (2) the contamination of pyrite surfaces by carbonaceous matter, and (3) pulp redox potentials. XPS (x-ray photoelectron spectroscopy) and IR spectrometry have been used to identify surface reaction products. Microflotation, laboratory-scale conventional flotation and microbubble column flotation were used to quantify the effects of these factors. It was found that low (reducing) pulp potentials are effective depressants of pyrite (more so for fresh, unoxidized samples than for oxidized samples), whilst at the same time do not materially affect coal flotation.
Date: June 24, 1992
Creator: Luttrell, G. H.; Yoon, R. H. & Ou, Z. S.
System: The UNT Digital Library
Control of pyrite surface chemistry in physical coal cleaning (open access)

Control of pyrite surface chemistry in physical coal cleaning

To better understand the surface chemical properties of coal and mineral pyrite, studies on the effect of flotation surfactants (frother and kerosene) on the degree of hydrophobicity have been conducted. The presence of either frother or kerosene enhanced the flotability of coal and mineral pyrite with a corresponding decrease in induction time over the pH range examined. Scanning electron microscopy (SEM) results indicate a correlation exists between the sample surface morphology and crystal structure and the observed hydrophobicity. As a result of the data obtained from the surface characterization studies, controlled surface oxidation was investigated as a possible pyrite rejection scheme in microbubble column flotation.
Date: June 24, 1992
Creator: Luttrell, G. H.; Yoon, R. H.; Zachwieja, J. & Lagno, M.
System: The UNT Digital Library
Control of pyrite surface chemistry in physical coal cleaning (open access)

Control of pyrite surface chemistry in physical coal cleaning

One of the most difficult separations in minerals processing involves the differential flotation of pyrite and coal. Under practical flotation conditions, they are both hydrophobic and no cost-effective method has been developed to efficiently reject the pyrite. The problem arises from inherent floatability of coal and pyrite. Coal is naturally hydrophobic and remains so under practical flotation. Although pyrite is believed to be naturally hydrophilic under practical flotation conditions it undergoes a relatively rapid incipient oxidation reaction that causes self-induced'' flotation. The oxidation product responsible for self-induced'' flotation is believed to be a metal polysulfide, excess sulfur in the lattice, or in some cases elemental sulfur. It is believed that if incipient oxidation of pyrite could be prevented, good pyrite rejection could be obtained. In order to gain a better understanding of how pyrite oxidizes, a new method of preparing fresh, unoxidized pyrite surfaces and a new method of studying pyrite oxidation have been developed this reporting period.
Date: June 24, 1992
Creator: Yoon, R. H. & Richardson, P. R.
System: The UNT Digital Library
Control of pyrite surface chemistry in physical coal cleaning. Tenth quarterly progress report, December 1, 1991--February 29, 1992 (open access)

Control of pyrite surface chemistry in physical coal cleaning. Tenth quarterly progress report, December 1, 1991--February 29, 1992

One of the most difficult separations in minerals processing involves the differential flotation of pyrite and coal. Under practical flotation conditions, they are both hydrophobic and no cost-effective method has been developed to efficiently reject the pyrite. The problem arises from inherent floatability of coal and pyrite. Coal is naturally hydrophobic and remains so under practical flotation. Although pyrite is believed to be naturally hydrophilic under practical flotation conditions it undergoes a relatively rapid incipient oxidation reaction that causes ``self-induced`` flotation. The oxidation product responsible for ``self-induced`` flotation is believed to be a metal polysulfide, excess sulfur in the lattice, or in some cases elemental sulfur. It is believed that if incipient oxidation of pyrite could be prevented, good pyrite rejection could be obtained. In order to gain a better understanding of how pyrite oxidizes, a new method of preparing fresh, unoxidized pyrite surfaces and a new method of studying pyrite oxidation have been developed this reporting period.
Date: June 24, 1992
Creator: Yoon, R. H. & Richardson, P. R.
System: The UNT Digital Library
Control of pyrite surface chemistry in physical coal cleaning. Fifth quarterly progress report, September 1, 1990--November 30, 1990 (open access)

Control of pyrite surface chemistry in physical coal cleaning. Fifth quarterly progress report, September 1, 1990--November 30, 1990

The successful separation of pyrite from coal by flotation is dependent to a large extent upon the selectivity of the process, and the use of a pyrite depressant is one of the most important and cost-effective techniques for achieving this. This report evaluates the effects of three factors on the floatability of pyrite. These are (1) the superficial oxidation of pyrite, (2) the contamination of pyrite surfaces by carbonaceous matter, and (3) pulp redox potentials. XPS (x-ray photoelectron spectroscopy) and IR spectrometry have been used to identify surface reaction products. Microflotation, laboratory-scale conventional flotation and microbubble column flotation were used to quantify the effects of these factors. It was found that low (reducing) pulp potentials are effective depressants of pyrite (more so for fresh, unoxidized samples than for oxidized samples), whilst at the same time do not materially affect coal flotation.
Date: June 24, 1992
Creator: Luttrell, G. H.; Yoon, R. H. & Ou, Z. S.
System: The UNT Digital Library
Control of pyrite surface chemistry in physical coal cleaning. Third quarterly progress report, March 1, 1990--May 31, 1990 (open access)

Control of pyrite surface chemistry in physical coal cleaning. Third quarterly progress report, March 1, 1990--May 31, 1990

Correlation of the hydrophobicity measurements of coal and mineral pyrite with changes in the surface composition of the samples as determined by x-ray photoelectron spectroscopy (XPS) reveals that similar surface oxidation products are found on both mineral and coal pyrite samples. The surface oxidation layer of these samples is comprised of different amounts of hydrophilic species (iron hydroxy-oxides and/or iron oxides) and hydrophobic species (polysulfide or elemental sulfur). The resulting hydrophobicity of these samples may be attributed to the ratio of hydrophilic (surface oxides) to hydrophobic (sulfur-containing) species in the surface oxidation layer. Also, coal pyrite samples were found to exhibit a greater degree of superficial oxidation and a less hydrophobic character as compared to the mineral pyrite samples.
Date: June 24, 1992
Creator: Luttrell, G. H.; Yoon, R. H.; Zachwieja, J. B. & Lagno, M. L.
System: The UNT Digital Library
Control of pyrite surface chemistry in physical coal cleaning (open access)

Control of pyrite surface chemistry in physical coal cleaning

Correlation of the hydrophobicity measurements of coal and mineral pyrite with changes in the surface composition of the samples as determined by x-ray photoelectron spectroscopy (XPS) reveals that similar surface oxidation products are found on both mineral and coal pyrite samples. The surface oxidation layer of these samples is comprised of different amounts of hydrophilic species (iron hydroxy-oxides and/or iron oxides) and hydrophobic species (polysulfide or elemental sulfur). The resulting hydrophobicity of these samples may be attributed to the ratio of hydrophilic (surface oxides) to hydrophobic (sulfur-containing) species in the surface oxidation layer. Also, coal pyrite samples were found to exhibit a greater degree of superficial oxidation and a less hydrophobic character as compared to the mineral pyrite samples.
Date: June 24, 1992
Creator: Luttrell, G. H.; Yoon, R. H.; Zachwieja, J. B. & Lagno, M. L.
System: The UNT Digital Library
UMTRA Project Office Records Management Plan (open access)

UMTRA Project Office Records Management Plan

The Uranium Mill Tailings Remedial Action (UMTRA) Project Office maintains two distinct records handling areas. One of the areas is maintained by a Technical Assistance Contractor (TAC), and is referred to as the UMTRA Project Document Control Center (UPDCC). The UPDCC manages all UMTRA records except those dealing with contracts, personnel, budgeting, finance, and any other documents which are of a purely administrative nature. The second area, the UMTRA Project Administrative Files Collection (UPAFC), contains all those records listed above that are not managed by the UPDCC. This Records Management Plan (RMP) for the UPAFC will be the framework for identifying the elements and activities that relate to the management and operational aspects involved in the handling of UPAFC. Guidelines for the program will be obtained from US Department of Energy (DOE) Orders. DOE Orders implement the guidelines issued by the National Archives and Records Administration (NARA), the final authority for records management. The RMP will address the life cycle of records, including their creation, maintenance, use, and disposition.
Date: June 1, 1993
Creator: unknown
System: The UNT Digital Library
Mine-to-Mill Optimization of Aggregate Production (open access)

Mine-to-Mill Optimization of Aggregate Production

Mine-to-Mill optimization is a total systems approach to the reduction of energy and cost in mining and mineral processing operations. Developed at the Julius Krutschnitt Mineral Research Centre (JKMRC) in Queensland, Australia, the Mine-to-Mill approach attempts to minimize energy consumption through the optimization of all steps in the size reduction process. The approach involves sampling and modeling of blasting and processing, followed by computer simulation to optimize the operation and develop alternatives. The most promising alternatives are implemented, and sampling is conducted to quantify energy savings. In the current project, the primary objective is to adapt the JKMRC Mine-to-Mill technology to the aggregates industry. The second phase of this project is being carried out at the Pittsboro Quarry located south of Chapel Hill, North Carolina. This quarry is owned by 3M Corporation and operated by Luck Stone. Based on lessons learned from the first phase work, long-term monitoring ({approx} three months) of all quarry operations is being carried out to minimize the impact of geological changes during the mining process. To date, the blasting and processing operations have been audited and modeled, the long-term monitoring of current Luck Stone practice has been completed, and a modified blasting approach has been …
Date: June 1, 2006
Creator: Adel, Greg; Kojovic, Toni & Thornton, Darren
System: The UNT Digital Library
Next Generation Extractants for Cesium Separation from High-Level Waste: From Fundamental Concepts to Site Implementation (open access)

Next Generation Extractants for Cesium Separation from High-Level Waste: From Fundamental Concepts to Site Implementation

This project seeks a fundamental understanding and major improvement in cesium separation from high-level waste by cesium-selective calixcrown extractants. Systems of particular interest involve novel solvent-extraction systems containing specific members of the calix[4]arene-crown-6 family, alcohol solvating agents, and alkylamines. Questions being addressed bear upon cesium binding strength, extraction selectivity, cesium stripping, and extractant solubility. Enhanced properties in this regard will specifically benefit applied projects funded by the USDOE Office of Environmental Management to clean up sites such as the Savannah River Site (SRS), Hanford, and the Idaho National Environmental and Engineering Laboratory. The most direct beneficiary will be the SRS Salt Processing Project, which has recently identified the Caustic-Side Solvent Extraction (CSSX) process employing a calixcrown as its preferred technology for cesium removal from SRS high-level tank waste.
Date: June 1, 2002
Creator: Moyer, Bruce A.; Bonnesen, Peter V.; Bryan, Jeffrey C.; Engle, Nancy L.; Keever, Tamara J.; Levitskaia, Tatiana G. et al.
System: The UNT Digital Library
OPTICAL FIBER SENSOR TECHNOLOGIES FOR EFFICIENT AND ECONOMICAL OIL RECOVERY (open access)

OPTICAL FIBER SENSOR TECHNOLOGIES FOR EFFICIENT AND ECONOMICAL OIL RECOVERY

Efficient recovery of petroleum reserves from existing oil wells has been proven to be difficult due to the lack of robust instrumentation that can accurately and reliably monitor processes in the downhole environment. Commercially available sensors for measurement of pressure, temperature, and fluid flow exhibit shortened lifetimes in the harsh downhole conditions, which are characterized by high pressures (up to 20 kpsi), temperatures up to 250 C, and exposure to chemically reactive fluids. Development of robust sensors that deliver continuous, real-time data on reservoir performance and petroleum flow pathways will facilitate application of advanced recovery technologies, including horizontal and multilateral wells. This is the final report for the four-year program ''Optical Fiber Sensor Technologies for Efficient and Economical Oil Recovery'', funded by the National Petroleum Technology Office of the U.S. Department of Energy, and performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech from October 1, 1999 to March 31, 2003. The main objective of this research program was to develop cost-effective, reliable optical fiber sensor instrumentation for real-time monitoring of various key parameters crucial to efficient and economical oil production. During the program, optical fiber sensors were demonstrated for …
Date: June 1, 2003
Creator: Wang, Anbo; Cooper, Kristie L. & Pickrell, Gary R.
System: The UNT Digital Library
Restoring Sustainable Forests on Appalachian Mined Lands for Wood Products, Renewable Energy, Carbon Sequestration, and Other Ecosystems Services Quarterly Report (open access)

Restoring Sustainable Forests on Appalachian Mined Lands for Wood Products, Renewable Energy, Carbon Sequestration, and Other Ecosystems Services Quarterly Report

The overall purpose of this project is to evaluate the biological and economic feasibility of restoring high-quality forests on mined land, and to measure carbon sequestration and wood production benefits that would be achieved from forest restoration procedures. In this quarterly report, we present a preliminary comparison of the carbon sequestration potential of forests growing on 14 mined sites in a seven-state region in the Midwestern and Eastern Coalfields. Carbon contents of these forests were compared to adjacent forests on non-mined land. The study was installed as a 3 x 3 factorial in a random complete block design with three replications at each location. The treatments include three forest types (white pine, hybrid poplar, mixed hardwood) and three silvicultural regimes (competition control, competition control plus tillage, competition control plus tillage plus fertilization). Each individual treatment plot is 0.5 acres. Each block of nine plots requires 4.5 acres, and the complete installation at each site requires 13.5 acres. The plots at all three locations have been installed and the plot corners marked with PVC stakes. GPS coordinates of each plot have been collected. Soil samples were collected from each plot to characterize the sites prior to treatment. Analysis of soil samples …
Date: June 4, 2004
Creator: Burger, J.; Galbraith, J.; Fox, T.; Amacher, G.; Sullivan, J. & Zipper, C.
System: The UNT Digital Library
Final Report for National Transport Code Collaboration PTRANSP (open access)

Final Report for National Transport Code Collaboration PTRANSP

PTRANSP, which is the predictive version of the TRANSP code, was developed in a collaborative effort involving the Princeton Plasma Physics Laboratory, General Atomics Corporation, Lawrence Livermore National Laboratory, and Lehigh University. The PTRANSP/TRANSP suite of codes is the premier integrated tokamak modeling software in the United States. A production service for PTRANSP/TRANSP simulations is maintained at the Princeton Plasma Physics Laboratory; the server has a simple command line client interface and is subscribed to by about 100 researchers from tokamak projects in the US, Europe, and Asia. This service produced nearly 13000 PTRANSP/TRANSP simulations in the four year period FY 2005 through FY 2008. Major archives of TRANSP results are maintained at PPPL, MIT, General Atomics, and JET. Recent utilization, counting experimental analysis simulations as well as predictive simulations, more than doubled from slightly over 2000 simulations per year in FY 2005 and FY 2006 to over 4300 simulations per year in FY 2007 and FY 2008. PTRANSP predictive simulations applied to ITER increased eight fold from 30 simulations per year in FY 2005 and FY 2006 to 240 simulations per year in FY 2007 and FY 2008, accounting for more than half of combined PTRANSP/TRANSP service CPU resource …
Date: June 14, 2012
Creator: Kritz, Arnold H.
System: The UNT Digital Library
Restoring Sustainable Forests on Appalachian Mined Lands for Wood Products, Renewable Energy, Carbon Sequestration, and Other Ecosystems Services Quarterly Report (open access)

Restoring Sustainable Forests on Appalachian Mined Lands for Wood Products, Renewable Energy, Carbon Sequestration, and Other Ecosystems Services Quarterly Report

The overall purpose of this project is to evaluate the biological and economic feasibility of restoring high-quality forests on mined land, and to measure carbon sequestration and wood production benefits that would be achieved from forest restoration procedures. We are currently estimating the acreage of lands in VA, WV, KY, OH, and PA mined under SMCRA and reclaimed to non-forested post-mining land uses that are not currently under active management, and therefore can be considered as available for carbon sequestration. To determine actual sequestration under different forest management scenarios, a field study was installed as a 3 x 3 factorial in a random complete block design with three replications at each of three locations, Ohio, West Virginia, and Virginia. The treatments included three forest types (white pine, hybrid poplar, mixed hardwood) and three silvicultural regimes (competition control, competition control plus tillage, competition control plus tillage plus fertilization). Each individual treatment plot is 0.5 acres. Each block of nine plots is 4.5 acres, and the complete installation at each site is 13.5 acres. During the reporting period we compiled and evaluated all soil properties measured on the study sites. Statistical analysis of the properties was conducted, and first year survival and …
Date: June 8, 2005
Creator: Burger, James A.; Galbraith, J.; Fox, T.; Amacher, G.; Sullivan, J. & Zipper, C.
System: The UNT Digital Library
CdSiAs/sub 2/ thin films for solar cell applications. Final report, April 9, 1979-April 8, 1980 (open access)

CdSiAs/sub 2/ thin films for solar cell applications. Final report, April 9, 1979-April 8, 1980

Compounds of Cd-Si-As required for sputtering targets and evaporation charges were synthesized by direct fusion. These include CdSiAs/sub 2/, Cd/sub 3/As/sub 2/, CdAs/sub 2/ and SiAs. Polycrystalline ingots of CdSiAs/sub 2/ were found to be porous, with the chalcopyrite structure, and with minor amounts of other phases such as CdAs/sub 2/, SiAs,As and Cd/sub 3/As/sub 2/. Sputtered films were formed in a single target RF system. A homogeneous CdSiAs/sub 2/ target was initially used, followed by composite targets consisting of CdAs/sub 2/ + Si. Films from the latter targets were superior to the others and were more extensively studied. As deposited films were amorphous, off stoichiometry, with resistivities over 10/sup 8/..cap omega..-cm and band gaps of approx. 1.4 eV. Subsequent reactive heat treatments in the 515/sup 0/ to 615/sup 0/C range resulted in crystalline films, resistivities of 1 to 10 ..cap omega.. cm, CdSiAs/sub 2/ compositions within 1% of stoichiometry, energy gap of approx. 1.55 eV, absorption coefficient of 2 x 10/sup 4/cm/sup -1/ at 0.6 ..mu..m, but with poor mechanical properties (mainly cracking). A Ta/Si0/sub 2/ substrate proved to be the best for these films. Thermal evaporation studies of CdSiAs/sub 2/ established that effusion is preferential toward Cd between …
Date: June 1, 1980
Creator: Burton, L.C. & Slack, L.H.
System: The UNT Digital Library
THREE DIMENSIONAL INTEGRATED CHARACTERIZATION AND ARCHIVING SYSTEM (3D-ICAS) (open access)

THREE DIMENSIONAL INTEGRATED CHARACTERIZATION AND ARCHIVING SYSTEM (3D-ICAS)

The overall objective of this project is to develop an integrated system that remotely characterizes, maps, and archives measurement data of hazardous decontamination and decommissioning (D&D) areas. The system will generate a detailed 3-dimensional topography of the area as well as real-time quantitative measurements of volatile organics and radionuclides. The system will analyze substrate materials consisting of concrete, asbestos, and transite. The system will permanently archive the data measurements for regulatory and data integrity documentation. Exposure limits, rest breaks, and donning and removal of protective garments generate waste in the form of contaminated protective garments and equipment. Survey times are increased and handling and transporting potentially hazardous materials incur additional costs. Off-site laboratory analysis is expensive and time-consuming, often necessitating delay of further activities until results are received. The Three Dimensional Integrated Characterization and Archiving System (3D-ICAS) has been developed to alleviate some of these problems. 3D-ICAS provides a flexible system for physical, chemical and nuclear measurements reduces costs and improves data quality. Operationally, 3D-ICAS performs real-time determinations of hazardous and toxic contamination. A prototype demonstration unit is available for use in early 2000. The tasks in this Phase included: (1) Mobility Platforms: Integrate hardware onto mobility platforms, upgrade surface …
Date: June 18, 2001
Creator: Jarvis, George
System: The UNT Digital Library