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Trace metal transformation in gasification

Description: The Energy & Environmental Research Center (EERC) is carrying out an investigation that will provide methods to predict the fate of selected trace elements in integrated gasification combined cycle (IGCC) and integrated gasification fuel cell (IGFC) systems to aid in the development of methods to control the emission of trace elements determined to be air toxics. The goal of this project is to identify the effects of critical chemical and physical transformations associated with trace element b… more
Date: December 31, 1996
Creator: Benson, Steven A.; Erickson, Thomas A.; Zygarlicke, Christopher J.; O'Keefe, Cathy A.; Katrinak, Karen A.; Allen, Sean E. et al.
Partner: UNT Libraries Government Documents Department
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Arsenic speciation in soil using high performance liquid chromatography/inductively coupled plasma/mass spectrometry

Description: A method has been developed to identify and quantify As(III), As(V), and organoarsenic compounds in soil samples from the Rocky Mountain Arsenal (RMA) by high performance liquid chromatography/inductively coupled plasma/mass spectrometry (HPLC/ICP/MS). The soils were extracted using tetrabutylammonium hydroxide (TBAH) and sonication. The percentages of As(III), As(V), and organoarsenic species extracted from soil samples were 30, 50, and 100 respectively. The arsenic species were not altered du… more
Date: August 1, 1996
Creator: Bass, D. A.; Yaeger, J. S.; Parish, K. J.; Crain, J. S.; Kiely, J. T.; Gowdy, M. J. et al.
Partner: UNT Libraries Government Documents Department
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First on-line results for As and F beams from HRIBF target/ion sources

Description: The first on-line tests of the ion sources to provide radioactive ion beams of {sup 69,70}As and {sup 17,18}F for the Holifield Radioactive Ion Beam Facility (HRIBF) have been performed using the UNISOR facility at HRIBF. The target/ion source is an electron beam plasma (EBP) source similar to the ISOLDE design. The measured efficiencies for {sup 69}As and {sup 70}AS were 0.5 {+-} 0.2% and 0.8 {+-} 0.3%, respectively. The arsenic hold-up time in the tested target ion source was 3.6 {+-} 0.3 hou… more
Date: December 31, 1996
Creator: Stracener, D.W.; Carter, H.K.; Kormicki, J.; Breitenbach, J.B.; Blackmon, J.C.; Smith, M.S. et al.
Partner: UNT Libraries Government Documents Department
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Portable sensor for hazardous waste

Description: We are part-way through the second phase of a 4-year program designed to develop a portable monitor for sensitive hazardous waste detection. The ultimate goal of the program is to develop our concept to the prototype instrument level. Our monitor will be a compact, portable instrument that will allow real-time, in situ, monitoring of hazardous wastes. This instrument will be able to provide the means for rapid field screening of hazardous waste sites to map the areas of greatest contamination. … more
Date: December 31, 1996
Creator: Piper, L. G.; Hunter, A. J. R.; Fraser, M. E. & Davis, S. J.
Partner: UNT Libraries Government Documents Department
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Novel materials and device design by metal-organic chemical vapor deposition for use in infrared emitters

Description: The authors have grown AlSb and AlAs{sub x}Sb{sub 1{minus}x} epitaxial layers by metal-organic chemical vapor deposition(MOCVD) using trimethylamine or ethyldimethylamine alane, triethylantimony and arsine. These layers were successfully doped p- or n-type using diethylzinc or tetraethyltin, respectively. They examined the growth of AlAs{sub x}Sb{sub 1{minus}x} using temperatures of 500 to 600 C, pressures of 65 to 630 torr, V/III ratios of 1--17, and growth rates of 0.3 to 2.7 {micro}m/hour in… more
Date: December 1, 1996
Creator: Biefeld, R. M.; Kurtz, S. R. & Allerman, A. A.
Partner: UNT Libraries Government Documents Department
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Increased emphasis on toxics control in oil and gas industry NPDES permits

Description: The 1987 amendments to the Clean Water Act emphasized stricter control of toxics in wastewater discharges. Although state and U.S. Environmental Protection Agency permit writers have had the authority to incorporate strict water quality-based controls in permits, they did not widely use this authority in the past. However, general permits proposed in the past year by Region VI for discharges into the territorial seas of Louisiana and by Region X for coastal and offshore discharges in Alaska are… more
Date: October 1, 1996
Creator: Veil, J.A.
Partner: UNT Libraries Government Documents Department
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1993 to 1995 environmental surveillance data collected at or near Area G

Description: This report summarizes Environmental Surveillance data collected by the Water Quality and Hydrology Group during 1993, 1994, and 1995 at or in the vicinity of TA-54, Area-G of the Los Alamos National Laboratory, New Mexico. The summary includes radiochemical, metals, general inorganic, and organic analytical results. The tables list measured concentrations (or detection limits for results below detection limits), analytical uncertainties for radiochemical data, sample locations, and sample date… more
Date: September 1, 1996
Creator: Mullen, K.; Collins, S. & Rogers, D.
Partner: UNT Libraries Government Documents Department
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Statement of basis/proposed plan for the Central Shops Burning/Rubble Pit (631-6G). Revision 1, Final

Description: The purpose of this plan is to describe the preferred alternative for addressing the Central Shops Burning/Rubble Pit 631-6G (BRP6G) located at SRS, in northwestern Barnwell County, South Carolina and to provide an opportunity for public input into the remedial action selection process. Arsenic, beryllium, iron, and octachloro-dibenzo-p-dioxin isomers (OCDD) concentrations in the pit soil are at levels consistent with those found in the background. Therefore, the only contamination attributable… more
Date: October 24, 1996
Creator: Palmer, E.
Partner: UNT Libraries Government Documents Department
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Trace elements in coal: Modes of occurrence analysis. Technical progress report, October 5, 1995--March 31, 1996

Description: CQ, Inc. proposed to quantify the relationship between the modes of occurrence of twelve trace hazardous air pollutants (HAP`s) elements in coal and the degree that each element can be removed by existing and advanced physical and chemical coal cleaning processes. They also proposed to investigate new chemical and biological trace element removal processes, and estimate the concentration and stability of trace elements in coal preparation plant tailings. The ultimate goal of this effort is to p… more
Date: October 1, 1996
Creator: Palmer, C.A.; Findelman, R.B.; Belkin, H.E. & Crowley, S.S.
Partner: UNT Libraries Government Documents Department
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First on-line results for As and F beams from HRIBF target/ion sources

Description: The first on-line tests of the ion sources to provide radioactive ion beams of {sup 69,70}As and {sup 17,18}F for the Holifield Radioactive Ion Beam Facility have been performed using the UNISOR facility at HRIBF. For {sup 70}As the measured efficiency is 0.8 {+-} 0.3% with a hold-up time of 3.6 {+-} 0.3 hours as measured with {sup 72}As at a target temperature of 1,270 C. For {sup 17}F the efficiency for Al{sup 17}F is 0.0024 {+-} 0.0008% with a hold-up time of 16.4 {+-} 0.8 m as measured with… more
Date: December 31, 1996
Creator: Carter, H.K.; Kormicki, J.; Stracener, D.W.; Breitenbach, J.B.; Blackmon, J.C.; Smith, M.S. et al.
Partner: UNT Libraries Government Documents Department
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Toxic substances from coal combustion - forms of occurrence analyses. Progress report, April 30, 1996 - November 1, 1996

Description: The Pittsburgh, Elkhorn/Hazard, and Illinois No. 6 program coals have been examined to determine the mode of occurrence of selected trace elements using scanning electron microscopy, microprobe analysis, and experimental leaching procedures. Preliminary microprobe data indicates that the arsenic content of pyrite grains in the Illinois No. 6 and Pittsburgh coals is similar. Pyrite grains observed in the Elkhorn/Hazard coal generally have arsenic concentrations that are slightly higher than thos… more
Date: December 1, 1996
Creator: Crowley, Sharon S.; Palmer, Curtis A.; Kolker, Allan; Finkelman, Robert B.; Kolb, Kathleen C. & Belkin, Harvey E.
Partner: UNT Libraries Government Documents Department
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Thermodynamic stability of complexes of BF{sub 3}, PF{sub 5} and AsF{sub 5} with chlorine fluorides, oxyfluorides, and related compounds

Description: The recent discovery of solid, water sensitive, arsenic-containing deposits in auxiliary process piping in the PGDP led to a search for explanations that could account for such accumulated material. A plausible explanation for the deposits is the formation of complexes of AsF{sub 5} with one or more gases that may have been present as a result of cascade equipment cleanup activities. A literature search was performed. The target of the search was literature that would provide information on the… more
Date: July 1, 1996
Creator: Trowbridge, L.D.
Partner: UNT Libraries Government Documents Department
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Molecular dynamics simulation of low energy boron and arsenic implant into silicon

Description: We have studied the implantation of boron and arsenic ions into silicon by classical molecular dynamics simulation. Single ion implant into the dimer reconstructed Si{l_brace}100{r_brace}(2x1) surface has been examined at energies between 0.25 keV and 5.0 keV, at both normal incidence and at non-channeling incidence. By using a new model for electronic stopping, developed for semiconductors and containing only one fitted parameter, we have been able to accurately calculate the depth profile of … more
Date: July 1, 1996
Creator: Beardmore, K.; Cai, D. & Gronbech-Jensen, N.
Partner: UNT Libraries Government Documents Department
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Detection of arsenic by resonance ionization mass spectrometry

Description: This is the final report of a two-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The development of sensitive analytical techniques for environmental analysis is a problem of immediate interest. Waste residues containing heavy metals such as chromium, lead and arsenic are particular problems due to their widespread usage and sometime incomplete recovery or inadequate storage. The objective of this project was to apply resonance io… more
Date: March 1, 1996
Creator: Nogar, N.; Anderson, J.; Allen, T. & Smith, C.
Partner: UNT Libraries Government Documents Department
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Interfacial arsenic from wet oxidation of Al{sub x}Ga{sub 1-X}As/GaAs: Its effects on electronic properties and new approaches to MIS device fabrication

Description: Three important oxidation regimes have been identified in the temporal evolution of the wet thermal oxidation of Al{sub x}Ga{sub 1-x}As (1 {ge} x {ge} 0.90) on GaAs: (1) oxidation of Al and Ga in the Al{sub x}Ga{sub 1-x}As alloy to form an amorphous oxide layer, (2) oxidative formation and elimination of elemental As (both crystalline and amorphous) and of amorphous As{sub 2}O{sub 3}, and (3) crystallization of the oxide film. Residual As can result in up to a 100-fold increase in leakage curre… more
Date: December 31, 1996
Creator: Ashby, C.I.H.; Sullivan, J.P. & Newcomer, P.P.
Partner: UNT Libraries Government Documents Department
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Assessment of HAPs emissions from advanced power systems

Description: The 1990 Clean Air Act Amendments (CAAA) identified 189 substances as air toxics or hazardous air pollutants (HAPs). Under the CAAA, the U. S. Environmental Protection Agency (EPA) must regulate emissions of these HAPs at their sources, including advanced power systems used for the production of electricity. Eleven trace elements are included in the CAAA list of HAPS, as shown in Table 1. The EPA will define those sources that require regulation and limit their emissions according to regulatory… more
Date: December 31, 1996
Creator: Erickson, T. A.; Brekke, D. W. & Botros, P. E.
Partner: UNT Libraries Government Documents Department
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Cooperative chemical rebonding in the segregation of impurities in silicon grain boundaries

Description: With ab initio calculations the authors show that the experimentally observed large segregation energies of As at Si grain boundaries can be explained by the formation of isolated dimers or ordered chains of dimers of threefold-coordinated As along the cores of grain boundary dislocations. They also find the intriguing possibility that As segregation may drive structural transformation of certain grain boundaries. Recently, they have obtained the first atomic-resolution STEM images of As in a S… more
Date: December 1996
Creator: Maiti, A.; Chisholm, M. F.; Pennycook, S. J. & Pantelides, S. T.
Partner: UNT Libraries Government Documents Department
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Toxic Substances from Coal Combustion: A Comprehensive Assessment: Quarterly report, 1 July 1996-30 September 1996

Description: The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPS) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the Pittsburgh Energy Technology Center (PETC), the Electric Power Research Institute (EPRI), and VTT (Finland), Physical Sciences In… more
Date: October 1, 1996
Creator: Bool, L. E.; Senior, C. L.; Huggins, F.; Huffman, G. P.; Shah, N.; Wendt, J. O. L. et al.
Partner: UNT Libraries Government Documents Department
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Toxic substances from coal combustion -- Forms of occurrence analyses. Technical progress report, April 30--November 1, 1996

Description: The overall objective of this project is to provide analytical support for the Physical Sciences, Inc. (PSI) effort being performed under a DOE Contract. The Pittsburgh, Elkhorn/Hazard, and Illinois No. 6 program coals have been examined to determine the mode of occurrence of selected trace elements using scanning electron microscopy, microprobe analysis, and experimental leaching procedures. Preliminary microprobe data indicates that the arsenic content of pyrite grains in the Illinois No. 6 (… more
Date: December 6, 1996
Creator: Crowley, Sharon S.; Palmer, Curtis A.; Kolker, Allan; Finkelman, Robert B.; Kolb, Kathleen C. & Belkin, Harvey E.
Partner: UNT Libraries Government Documents Department
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Toxicological benchmarks for wildlife: 1996 Revision

Description: The purpose of this report is to present toxicological benchmarks for assessment of effects of certain chemicals on mammalian and avian wildlife species. Publication of this document meets a milestone for the Environmental Restoration (ER) Risk Assessment Program. This document provides the ER Program with toxicological benchmarks that may be used as comparative tools in screening assessments as well as lines of evidence to support or refute the presence of ecological effects in ecological risk… more
Date: June 1, 1996
Creator: Sample, B. E.; Opresko, D. M. & Suter, G. W. II
Partner: UNT Libraries Government Documents Department
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Development of a field-portable air monitor for Lewisite

Description: The focus of this research is the development of a prototype field-portable ambient-air monitor for measuring trace levels of volatile organoarsenicals. Lewisite (dichloro[2-chlorovinyl]arsine) is a chemical warfare agent developed during World War I and stockpiled on a large scale by the former Soviet Union. A continuous air monitor for Lewisite at the eight-hour time-weighted-average concentration (3 {mu}g/m{sup 3}) is necessary to protect the safety and health of arms control treaty inspecto… more
Date: March 1, 1996
Creator: Aldstadt, J. H.; Martin, A. F. & Olson, D. C.
Partner: UNT Libraries Government Documents Department
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Interactions between trace metals, sodium and sorbents in combustion. Quarterly report No. 5, October 1, 1995--December 30, 1995

Description: The proposed research is directed at an understanding of how to exploit interactions between sodium, toxic metals and sorbents, in order to optimize sorbents injection procedures,which can be used to capture and transform these metals into environmentally benign forms. The research will use a 17kW downflow, laboratory combustor, to yield data that can be interpreted in terms of fundamental kinetic mechanisms. Metals to be considered are lead, cadmium, and arsenic. Sorbents will be kaolinite, ba… more
Date: June 1, 1996
Creator: Wendt, J.O.L. & Davis, S.
Partner: UNT Libraries Government Documents Department
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Separations chemistry of toxic metals

Description: Sequestering and removing toxic metal ions from their surroundings is an increasingly active area of research and is gaining importance in light of current environmental contamination problems both within the DOE complex and externally. One method of separating metal ions is to complex them to a molecule (a ligand or chelator) which exhibits specific binding affinity for a toxic metal, even in the presence of other more benign metals. This approach makes use of the sometimes subtle differences … more
Date: April 1, 1996
Creator: Smith, P.; Barr, M. & Barrans, R.
Partner: UNT Libraries Government Documents Department
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The Growth of Mid-Infrared Lasers and AIAs{sub x}Sb{sub 1-x} by MOCVD

Description: We have grown AlSb and AlAs{sub x}Sb{sub 1-x} epitaxial layers by metal-organic chemical vapor deposition (MOCVD) using trimethylamine or ethyldimethylamine alane, triethylantimony and arsine. These layers were successfully doped p- or n-type using diethylzinc or tetraethyltin, respectively. We examined the growth of AlAs{sub x}Sb{sub 1-x} using temperatures of 500 to 600{degrees}C, pressures of 65 to 630 torr, V/III ratios of 1-17, and growth rates of 0.3 to 3.7 {mu}m/hour in a horizontal quar… more
Date: July 1, 1996
Creator: Biefeld, R. M.; Allerman, A. A. & Kurtz, S. R.
Partner: UNT Libraries Government Documents Department
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