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Photophoresis and the scattering of electromagnetic radiation

Description: Electron-microscope photographs of soot lend support to the picture in which a soot particle is modeled as a collection of chains of small carbon spheres. The soot particle itself is typically considerably larger than the small carbon spheres making up the chains. Thus the soot particles might have a size approx.0.1 - 1 ..mu..m while the small carbon spheres might have a size approx.0.03 ..mu..m in typical situations. Further, measurements of the density of soot yield values much less than that… more
Date: September 1, 1985
Creator: Ipser, J.R.
Partner: UNT Libraries Government Documents Department
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Extraction and identification of organic materials present in soot from a natural gas flame

Description: Aliphatic and polynuclear aromatic hydrocarbons are readily extracted from soot formed from a natural gas flame using methylene chloride and ultrasonic agitation. Identification of 24 organic compounds via capillary column GC retention times and GC-MS data is reported along with details of experimental procedures.
Date: January 1, 1978
Creator: Vick, R.D. & Avery, M.J.
Partner: UNT Libraries Government Documents Department
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Aromatics oxidation and soot formation in flames

Description: Work during this contract period has been concerned with the mechanisms through which aromatics are formed and destroyed in flames, and the processes responsible for soot formation. Recent progress has been primarily in two areas: experiments and modeling of the soot nucleation process in low pressure benzene flames and preparation for experiments on the destruction mechanisms of benzene. In addition, we have incorporated weak collision'' formalisms into a fall-off computer code.
Date: January 1, 1989
Creator: Howard, J. B.
Partner: UNT Libraries Government Documents Department
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Soot in the stratosphere: The impact of current and HSCT aircraft emissions

Description: One of the trace components of emissions from aircraft engines and other combustion sources are soot particles. These particles are strongly absorbing in the visible and IR spectra, may act as condensation nuclei, and may provide a large surface area for the catalytic promotion of gas-phase chemical reactions. Soot if found throughout the troposphere, even at remote locations, and also in the stratosphere. Present techniques do not allow an unambiguous identification of the sources. This paper … more
Date: August 1, 1991
Creator: Hansen, A.D.A. (Lawrence Berkeley Lab., CA (United States)); Pueschel, R.F. & Snetsinger, K.G. (National Aeronautics and Space Administration, Moffett Field, CA (United States). Ames Research Center)
Partner: UNT Libraries Government Documents Department
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Combustion of ultrafine coal/water mixtures and their application in gas turbines: Final report

Description: The feasibility of using coal-water fuels (CWF) in gas turbine combustors has been demonstrated in recent pilot plant experiments. The demands of burning coal-water fuels with high flame stability, complete combustion, low NO/sub x/ emission and a resulting fly ash particle size that will not erode turbine blades represent a significant challenge to combustion scientists and engineers. The satisfactory solution of these problems requires that the variation of the structure of CWF flames, i.e., … more
Date: October 1, 1987
Creator: Toqan, M.A.; Srinivasachar, S.; Staudt, J.; Varela, F. & Beer, J.M.
Partner: UNT Libraries Government Documents Department
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Health effects of combustion-generated soot and polycyclic aromatic hydrocarbons. Progress report, May 1, 1979-April 30, 1980. [Lead abstract]

Description: Mutagen studies on soot and soot components are reported in aspects dealing from quantitative chemical analyses of samples and mutagenesis of cells and microorganisms exposed to mutagens, to bioassay developments and techniques. Several polycyclic aromatic hydrocarbons are characterized and discussed.
Date: May 1, 1980
Creator: Thilly, W. G.
Partner: UNT Libraries Government Documents Department
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Photoassisted electrolysis applied to coal gasification. Third quarterly report, 1 January 1982-31 Mar 1982

Description: The literature search on electrochemical studies of various carbons has been completed. Two conclusions were reached: (1) The surfaces of various carbons are covered by oxide films to different extents and the oxides resemble either the quinone-like structure in their oxidized form or the hydroquinone-like structure in the reduced form. (2) When carbonaceous materials are oxidized chemically, electrochemically, or thermally, the first stage involves formation of the oxide film and the later sta… more
Date: January 1, 1982
Partner: UNT Libraries Government Documents Department
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Synthetic fuel utilization. Final report. Task 330

Description: The presence of large coal resources in this country provided the spur for consideration of liquids derived from hydrogenation of coal in the search for alternate liquid fuels to replace petroleum. Previous developments particularly in German industry beginning in 1910 and reaching a capacity of approximately four million tons of products a year by 1944 and more recently a series of plants in South Africa have shown the practicability of coal liquefaction. A few more advanced processes have bee… more
Date: January 1, 1983
Creator: Singer, S.
Partner: UNT Libraries Government Documents Department
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Fundamental combustion and diagnostics research at Sandia. Progress report, April-June 1980

Description: The combustion research emphasizes basic research into fundamental problems associated with combustion. The overall program addresses detailed chemistry of combustion, fundamental processes associated with laminar and turbulent flames, development of research techniques specifically applicable to combustion environments, and operation of the user-oriented Combustion Research Facility. The first section of this report contains activities in Combustion Research, the second section contains activi… more
Date: September 1, 1980
Creator: Gusinow, M.A. (ed.)
Partner: UNT Libraries Government Documents Department
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Synthetic fuel aromaticity and staged combustion

Description: Samples of middle and heavy SRC-II distillates were distilled into 50 C boiling point range fractions. These were characterized by measurements of their molecular weight, elemental analysis and basic nitrogen content and calculation of average molecular structures. The structures typically consisted of 1 to 3 aromatic rings fused to alicyclic rings with short, 1 to 3 carbon aliphatic side chains. The lower boiling fractions contained significant amounts (1 atom/molecule) of oxygen while the hea… more
Date: November 15, 1982
Creator: Longanbach, J. R.; Chan, L. K. & Levy, A.
Partner: UNT Libraries Government Documents Department
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Microphysical/mesoscale aspects of nuclear winter and new directions in assessments

Description: Recent results of model studies and sensitivity tests have shown the degree to which the intensity and duration of ''nuclear winter'' depends on the mass of soot and dust suspended, its optical properties, its vertical distribution in the atmosphere, and the residence time. The soot from urban fires is viewed as evolving during its dispersion from the early fire induced plumes, to cloud scale systems, to the mesoscale and larger systems. Micro-physical processes are perceived as operating withi… more
Date: June 1, 1985
Creator: Knox, J.B.
Partner: UNT Libraries Government Documents Department
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Hydrocarbon autothermal reforming program. Final technical report, 28 September 1979-31 October 1981

Description: The goal of the PSI program was to understand the mechanisms of the formation of carbon deposits under conditions relevant to authothermal reformers (ATR). The first year of this two year program was dedicated almost entirely to investigations of gas phase soot formation. It was speculated that soot could form in the gas phase and deposit downstream in the catalyst bed. A high temperature experimental test rig was constructed and comptuer models developed to aid in understanding this process. T… more
Date: February 1, 1982
Creator: Ham, D.O.; Lewis, P.F.; Lord, G.W.; Yarrington, R.M. & Hwang, H.S.
Partner: UNT Libraries Government Documents Department
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Application of the optical absorption technique to the characterization of the carbonaceous component of ambient and source particulate samples

Description: The optical absorption properties of some ambient and source particulate samples have been measured. These results suggest that the absorptivity is due to graphitic soot and that a major fraction of the ambient carbonaceous aerosol in the winter and summer episodes investigated is primary in origin.
Date: October 1, 1977
Creator: Rosen, H.; Hansen, A.D.A.; Dod, R.L. & Novakov, T.
Partner: UNT Libraries Government Documents Department
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A Chemical Kinetic Modeling Study of the Effects of Oxygenated Hydrocarbons on Soot Emissions from Diesel Engines

Description: A detailed chemical kinetic modeling approach is used to examine the phenomenon of suppression of sooting in diesel engines by addition of oxygenated hydrocarbon species to the fuel. This suppression, which has been observed experimentally for a few years, is explained kinetically as a reduction in concentrations of soot precursors present in the hot products of a fuel-rich diesel ignition zone when oxygenates are included. Oxygenates decrease the overall equivalence ratio of the igniting mixtu… more
Date: November 14, 2005
Creator: Westbrook, C K; Pitz, W J & Curran, H J
Partner: UNT Libraries Government Documents Department
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Characterization of soot properties in two-meter JP-8 pool fires.

Description: The thermal hazard posed by large hydrocarbon fires is dominated by the radiative emission from high temperature soot. Since the optical properties of soot, especially in the infrared region of the electromagnetic spectrum, as well as its morphological properties, are not well known, efforts are underway to characterize these properties. Measurements of these soot properties in large fires are important for heat transfer calculations, for interpretation of laser-based diagnostics, and for devel… more
Date: February 1, 2005
Creator: Suo-Anttila, Jill Marie; Jensen, Kirk A. & Blevins, Linda Gail (Sandia National Laboratories, Livermore, CA)
Partner: UNT Libraries Government Documents Department
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Revolutionary systems for catalytic combustion and diesel catalytic particulate traps.

Description: This report is a summary of an LDRD project completed for the development of materials and structures conducive to advancing the state of the art for catalyst supports and diesel particulate traps. An ancillary development for bio-medical bone scaffolding was also realized. Traditionally, a low-pressure drop catalyst support, such as a ceramic honeycomb monolith, is used for catalytic reactions that require high flow rates of gases at high-temperatures. A drawback to the traditional honeycomb m… more
Date: December 1, 2004
Creator: Stuecker, John Nicholas; Witze, Peter O.; Ferrizz, Robert Matthew; Cesarano, Joseph, III & Miller, James Edward
Partner: UNT Libraries Government Documents Department
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Uncertainty analysis of heat flux measurements estimated using a one-dimensional, inverse heat-conduction program.

Description: The measurement of heat flux in hydrocarbon fuel fires (e.g., diesel or JP-8) is difficult due to high temperatures and the sooty environment. Un-cooled commercially available heat flux gages do not survive in long duration fires, and cooled gages often become covered with soot, thus changing the gage calibration. An alternate method that is rugged and relatively inexpensive is based on inverse heat conduction methods. Inverse heat-conduction methods estimate absorbed heat flux at specific mate… more
Date: February 1, 2005
Creator: Nakos, James Thomas; Figueroa, Victor G. & Murphy, Jill E. (Worcester Polytechnic Institute, Worcester, MA)
Partner: UNT Libraries Government Documents Department
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Soot formation, transport, and radiation in unsteady diffusion flames : LDRD final report.

Description: Fires pose the dominant risk to the safety and security of nuclear weapons, nuclear transport containers, and DOE and DoD facilities. The thermal hazard from these fires primarily results from radiant emission from high-temperature flame soot. Therefore, it is necessary to understand the local transport and chemical phenomena that determine the distributions of soot concentration, optical properties, and temperature in order to develop and validate constitutive models for large-scale, high-fide… more
Date: October 1, 2004
Creator: Suo-Anttila, Jill Marie (Sandia National Laboratories, Albuquerque, NM); Williams, Timothy C.; Shaddix, Christopher R.; Jensen, Kirk A. (Sandia National Laboratories, Albuquerque, NM); Blevins, Linda Gail; Kearney, Sean Patrick (Sandia National Laboratories, Albuquerque, NM) et al.
Partner: UNT Libraries Government Documents Department
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A joint computational and experimental study to evaluate Inconel-sheathed thermocouple performance in flames.

Description: A joint experimental and computational study was performed to evaluate the capability of the Sandia Fire Code VULCAN to predict thermocouple response temperature. Thermocouple temperatures recorded by an Inconel-sheathed thermocouple inserted into a near-adiabatic flat flame were predicted by companion VULCAN simulations. The predicted thermocouple temperatures were within 6% of the measured values, with the error primarily attributable to uncertainty in Inconel 600 emissivity and axial conduct… more
Date: September 1, 2005
Creator: Brundage, Aaron L.; Nicolette, Vernon F.; Donaldson, A. Burl; Kearney, Sean Patrick & Gill, Walter
Partner: UNT Libraries Government Documents Department
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Correlations between Optical, Chemical and Physical Properties of Biomass Burn Aerosols

Description: Aerosols generated from burning different plant fuels were characterized to determine relationships between chemical, optical and physical properties. Single scattering albedo ({omega}) and Angstrom absorption coefficients ({alpha}{sub ap}) were measured using a photoacoustic technique combined with a reciprocal nephelometer. Carbon-to-oxygen atomic ratios, sp{sup 2} hybridization, elemental composition and morphology of individual particles were measured using scanning transmission X-ray micro… more
Date: January 29, 2008
Creator: Hopkins, Rebecca J.; Lewis, K.; Desyaterik, Yury; Wang, Z.; Tivanski, Alexei V.; Arnott, W. P. et al.
Partner: UNT Libraries Government Documents Department
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Weathering of Roofing Materials-An Overview

Description: An overview of several aspects of the weathering of roofing materials is presented. Degradation of materials initiated by ultraviolet radiation is discussed for plastics used in roofing, as well as wood and asphalt. Elevated temperatures accelerate many deleterious chemical reactions and hasten diffusion of material components. Effects of moisture include decay of wood, acceleration of corrosion of metals, staining of clay, and freeze-thaw damage. Soiling of roofing materials causes objectionab… more
Date: March 30, 2006
Creator: Berdahl, Paul; Akbari, Hashem; Levinson, Ronnen & Miller, William A.
Partner: UNT Libraries Government Documents Department
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NOx Control Options and Integration for US Coal Fired Boilers: Final Report

Description: This is the Final Report for DOE Cooperative Agreement No: DE-FC26-00NT40753. The goal of the project was to develop cost-effective analysis tools and techniques for demonstrating and evaluating low-NOx control strategies and their possible impact on boiler performance for boilers firing US coals. The Electric Power Research Institute (EPRI) provided co-funding for this program. This project included research on: (1) In furnace NOx control; (2) Impacts of combustion modifications on boiler oper… more
Date: June 30, 2006
Creator: Bockelie, Mike; Cremer, Marc; Davis, Kevin; Denison, Martin; Sarofim, Adel; Senior, Connie et al.
Partner: UNT Libraries Government Documents Department
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Soot properties and species measurements in a two-meter diameter JP-8 pool fire : 2003 test series.

Description: A tunable diode laser absorption spectroscopy probe was used to measure in situ soot properties and species concentrations in a two-meter diameter JP-8 pool fire. Thirty-five tests were performed at the Lurance Canyon Burn Site operated by Sandia in Albuquerque, New Mexico. The axial profile of the fire was characterized with a series of tests with the probe located on the centerline at heights ranging from 0.5 m to 2.0 m in 0.25 m increments. The radial profile of the fire was characterized wi… more
Date: March 1, 2004
Creator: Shaddix, Christopher R. & Murphy, Jeffrey J.
Partner: UNT Libraries Government Documents Department
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Effects of components of synfuels on soot formation. Quarterly technical progress report Number 3, April 1-June 30, 1981

Description: The objective of this project is to obtain information about the relationships between the rate and amount of soot formation in the combustion of coal-derived synfuels and the chemical composition and molecular constituents of those fuels. Simple bench-scale premixed and diffusion burners will be used at pressures between one and ten atmospheres to observe soot formation from fuel samples varying in their boiling range and contents of aromatic and heteroaromatic compounds. During this reporting… more
Date: August 1, 1981
Creator: Haebig, J. E. & Goldberg, P. M.
Partner: UNT Libraries Government Documents Department
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