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Electrochemistry applied to biomass. Progress report, October 1980-September 1981

Description: The electrochemical conversion of biomass-derived compounds, obtained through thermochemical pretreatments, into valuable organic chemicals, petrochemical substitutes, and energy-intensive chemicals is investigated. A hardwood-derived lignin obtained from ethanol extraction of the explosively depressurized aspen has been investigated. We have partially characterized this lignin material, and have also submitted it to electrolyses under controlled potential. The electrolytic conditions employed … more
Date: April 1, 1982
Creator: Chum, H. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recovery of anaerobic digestion after exposure to toxicants. Final report

Description: The concept that methane fermentation cannot tolerate chronic or slug doses of toxicants has almost totally precluded methane fermentation as a viable contender for the treatment of industrial wastewaters. This study assayed a wide variety of toxicants, heavy metals, inorganic salts, organic chemicals, solvents, and antibiotics which are used in industrial processes and, therefore, appear in the industrial wastewaters therefrom. Toxicity was related to the reduction in methane production of a c… more
Date: December 1, 1979
Creator: Yang, J.; Parkin, G. F. & Speece, R. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Heteronuclear dipolar couplings, total spin coherence, and bilinear rotations in NMR spectroscopy

Description: In Chapter 1 a variety of different introductory topics are presented. The potential complexity of the nuclear magnetic resonsnace (NMR) spectra of molecules dissolved in liquid crystal solvents serves to motivate the development of multiple quantum (MQ) spectroscopy. The basics of MQ NMR are reviewed in Chapter 2. An experimental search procedure for the optimization of MQ pulse sequences is introduced. Chapter 3 discusses the application of MQ NMR techniques to the measurement of dipolar coup… more
Date: July 1, 1983
Creator: Garbow, J.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanism and Kinetics of Fischer-Tropsch Synthesis Over Supported Ruthenium Catalysts

Description: A detailed study of the kinetics of the Fischer-Tropsch synthesis of hydrocarbons, methanol, and acetaldehyde, over alumina- and silica-supported ruthenium catalysts has been carried out over a broad range of reaction conditions. Based on these results and information taken from the literature, mechanisms for the formation of normal paraffins, ..cap alpha..-olefins, methanol, and acetaldehyde have been proposed. Rate data were obtained between 448 and 548K, 1 and 10 atm, and H/sub 2//CO ratios … more
Date: June 1, 1981
Creator: Kellner, C. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sulfided heterogeneous, bimetallic RuMo catalysts derived from mixtures of Ru sub 3 (CO) sub 12 (or RuCl sub 3 ) and a molybdenum heteropolyanion. The reactions of ethanol with tetrahydroquinoline

Description: Efforts have been made to develop Ru/Mo bimetallic catalyst systems for hydrodenitrogenation (HDN) of tetrahydroquinoline (THQ)- In the course of these studies, it was discovered that in ethanol, under H{sub 2} and in the presence Of CS2, Precatalyst solutions containing Ru (as Ru{sub 3} (CO){sub 12} or RuCl{sub 3}) and Mo (as the H{sub 3}PMO{sub 12}0{sub 40} heteropolyanion (HPA)) decompose to form bimetallic, sulfided particles. Particle diameters run from 0.1 to 5 {mu}m depending on the rate… more
Date: January 1, 1992
Creator: Koo, Sang-Man; Ryan, D. & Laine, R. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Products of the Thermal Decomposition of CH3CHO

Description: We have used a heated 2 cm x 1 mm SiC microtubular (mu tubular) reactor to decompose acetaldehyde: CH3CHO + DELTA --> products. Thermal decomposition is followed at pressures of 75 - 150 Torr and at temperatures up to 1700 K, conditions that correspond to residence times of roughly 50 - 100 mu sec in the mu tubular reactor. The acetaldehyde decomposition products are identified by two independent techniques: VUV photoionization mass spectroscopy (PIMS) and infrared (IR) absorption spectrosco… more
Date: April 6, 2011
Creator: Vasiliou, AnGayle; Piech, Krzysztof M.; Zhang, Xu; Nimlos, Mark R.; Ahmed, Musahid; Golan, Amir et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Secondary Pollutants from Ozone Reaction with Ventilation Filters and Degradation of Filter Media Additives

Description: Prior research suggests that chemical processes taking place on the surface of particle filters employed in buildings may lead to the formation of harmful secondary byproducts. We investigated ozone reactions with fiberglass, polyester, cotton/polyester and polyolefin filter media, as well as hydrolysis of filter media additives. Studies were carried out on unused media, and on filters that were installed for 3 months in buildings at two different locations in the San Francisco Bay Area. Specim… more
Date: May 1, 2011
Creator: Destaillats, Hugo; Chen, Wenhao; Apte, Michael; Li, Nuan; Spears, Michael; Almosni, Jérémie et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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NMOG Emissions Characterizations and Estimation for Vehicles Using Ethanol-Blended Fuels

Description: Ethanol is a biofuel commonly used in gasoline blends to displace petroleum consumption; its utilization is on the rise in the United States, spurred by the biofuel utilization mandates put in place by the Energy Independence and Security Act of 2007 (EISA). The United States Environmental Protection Agency (EPA) has the statutory responsibility to implement the EISA mandates through the promulgation of the Renewable Fuel Standard. EPA has historically mandated an emissions certification fuel s… more
Date: October 1, 2011
Creator: Sluder, Scott & West, Brian H
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Final Technical Report: Effects of Impurities on Fuel Cell Performance and Durability

Description: The main objectives of this project were to investigate the effect of a series of potential impurities on fuel cell operation and on the particular components of the fuel cell MEA, to propose (where possible) mechanism(s) by which these impurities affected fuel cell performance, and to suggest strategies for minimizing these impurity effects. The negative effect on Pt/C was to decrease hydrogen surface coverage and hydrogen activation at fuel cell conditions. The negative effect on Nafion compo… more
Date: November 11, 2011
Creator: Goodwin, James G., Jr.; Colon-Mercado, Hector; Hongsirikarn, Kitiya & Zhang, Jack Z.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of a Combined Ultraviolet Photocatalytic Oxidation(UVPCO)/Chemisorbent Air Cleaner for Indoor Air Applications

Description: We previously reported that gas-phase byproducts of incomplete oxidation were generated when a prototype ultraviolet photocatalytic oxidation (UVPCO) air cleaner was operated in the laboratory with indoor-relevant mixtures of VOCs at realistic concentrations. Under these conditions, there was net production of formaldehyde and acetaldehyde, two important indoor air toxicants. Here, we further explore the issue of byproduct generation. Using the same UVPCO air cleaner, we conducted experiments t… more
Date: February 1, 2007
Creator: Hodgson, Alfred T.; Destaillats, Hugo; Hotchi, Toshifumi & Fisk,William J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Final Report, "Molecular Design of Hydrocarbon Oxidation Catalytic Processes"

Description: The main goal of this project had been to use model systems to correlate selectivities in partial oxidation catalysis with the presence of specific sites on the surface of the catalyst. Extensive work was performed this year on characterizing oxygen-treated nickel surfaces by chemical means. Specifically, the surface chemistry of ammonia coadsorbed with atomic oxygen on Ni(110) single-crystal surfaces was studied by temperature-programmed desorption (TPD) and X-ray photoelectron spectroscopy (X… more
Date: August 9, 2007
Creator: Zaera, Francisco
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Indoor Secondary Pollutants from Household Product Emissions inthe Presence of Ozone: A Bench-Scale Chamber Study

Description: Ozone-driven chemistry is a major source of indoor secondary pollutants of health concern. This study investigates secondary air pollutants formed from reactions between constituents of household products and ozone. Gas-phase product emissions were introduced along with ozone at constant rates into a 198-L Teflon-lined reaction chamber. Gas-phase concentrations of reactive terpenoids and oxidation products were measured. Formaldehyde was a predominant oxidation byproduct for the three studied p… more
Date: October 1, 2005
Creator: Destaillats, Hugo; Lunden, Melissa M.; Singer, Brett C.; Coleman,Beverly K.; Hodgson, Alfred T.; Weschler, Charles J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation of IAQ-Relevant Surface Chemistry and Emissions on HVAC Filter Materials

Description: Chemical reactions involving ozone of outdoor origin and indoor materials are known to be significant sources of formaldehyde and other irritant gas-phase oxidation products in the indoor environment. HVAC filters are exposed to particularly high ozone concentrations--close to outdoor levels. In this study, we investigated chemical processes taking place on the surface of filters that included fiberglass, polyester, cotton/polyester blend and synthetic (e.g., polyolefin) filter media. Ozone rea… more
Date: February 1, 2010
Creator: Destaillats, Hugo & Fisk, William J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hazard Assessment of Chemical Air Contaminants Measured in Residences

Description: Identifying air pollutants that pose a potential hazard indoors can facilitate exposure mitigation. In this study, we compiled summary results from 77 published studies reporting measurements of chemical pollutants in residences in the United States and in countries with similar lifestyles. These data were used to calculate representative mid-range and upper bound concentrations relevant to chronic exposures for 267 pollutants and representative peak concentrations relevant to acute exposures f… more
Date: May 10, 2010
Creator: Logue, J.M.; McKone, T.E.; Sherman, M. H. & Singer, B.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Parametric Evaluation of an Innovative Ultra-Violet PhotocatalyticOxidation (UVPCO) Air Cleaning Technology for Indoor Applications

Description: An innovative Ultra-Violet Photocatalytic Oxidation (UVPCO) air cleaning technology employing a semitransparent catalyst coated on a semitransparent polymer substrate was evaluated to determine its effectiveness for treating mixtures of volatile organic compounds (VOCs) representative of indoor environments at low, indoor-relevant concentration levels. The experimental UVPCO contained four 30 by 30-cm honeycomb monoliths irradiated with nine UVA lamps arranged in three banks. A parametric evalu… more
Date: October 31, 2005
Creator: Hodgson, Alfred T.; Sullivan, Douglas P. & Fisk, William J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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SELECTIVE REDUCTION OF NOX IN OXYGEN RICH ENVIRONMENTS WITH PLASMA-ASSISTED CATALYSIS: CATALYST DEVELOPMENT AND MECHANISTIC STUDIES

Description: The control of NOx (NO and NO2) emissions from so-called ''lean-burn'' vehicle engines remains a challenge. In recent years, there have been a number of reports that show that a plasma device combined with a catalyst can reduce as high as 90% or more of NOx in simulated diesel and other ''lean-burn'' exhaust. In the case of propylene containing simulated diesel exhaust, the beneficial role of a plasma treatment is now thought to be due to oxidation of NO to NO2, and the formation of partially o… more
Date: August 24, 2003
Creator: Peden, C.; Barlow, S.; Hoard, J.; Kwak, J.; Balmer-Millar, M.; Panov, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Multiresonant Spectroscopy and the High-Resolution Threshold Photoionization of Combustion Free Radicals

Description: This report describes the results of a program of research on the thermochemistry, spectroscopy and intramolecular relaxation dynamics of the combustion intermediate, HCO. We prepare this radical from acetaldehyde as a photo-precursor in a differentially pumped laser-ionization source quadrupole mass spectrometer. Using a multiresonant spectroscopic technique established in our laboratory, we select individual rotational states and overcome Franck-Condon barriers associated with neutral-to-cati… more
Date: September 7, 2005
Creator: Grant, Edward R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Infrared Absorption Spectroscopy and Chemical Kinetics of Free Radicals

Description: This research was directed at the detection, monitoring, and study of the chemical kinetic behavior by infrared absorption spectroscopy of small free radical species thought to be important intermediates in combustion. Work on the reaction of OH with acetaldehyde has been completed and published and work on the reaction of O({sup 1}D) with CH{sub 4} has been completed and submitted for publication. In the course of our investigation of branching ratios of the reactions of O({sup 1}D) with aceta… more
Date: November 1, 2004
Creator: Curl, Robert F & Glass, Graham
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Selective oxidation of methanol and ethanol on supported ruthenium oxide clusters at low temperatures

Description: RuO2 domains supported on SnO2, ZrO2, TiO2, Al2O3, and SiO2 catalyze the oxidative conversion of methanol to formaldehyde, methylformate, and dimethoxymethane with unprecedented rates and high combined selectivity (>99 percent) and yield at low temperatures (300-400 K). Supports influence turnover rates and the ability of RuO2 domains to undergo redox cycles required for oxidation turnovers. Oxidative dehydrogenation turnover rates and rates of stoichiometric reduction of RuO2 in H2 increase… more
Date: March 4, 2004
Creator: Liu, Haichao & Iglesia, Enrique
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Selective Catalytic Reduction of Diesel Engine Nox Emissions Using Ethanol as a Reductant

Description: NOx emissions from a heavy-duty diesel engine were reduced by more than 90% and 80% utilizing a full-scale ethanol-SCR system for space velocities of 21000/h and 57000/h respectively. These results were achieved for catalyst temperatures between 360 and 400 C and for C1:NOx ratios of 4-6. The SCR process appears to rapidly convert ethanol to acetaldehyde, which subsequently slipped past the catalyst at appreciable levels at a space velocity of 57000/h. Ammonia and N2O were produced during conve… more
Date: August 24, 2003
Creator: Kass, M. D.; Thomas, J. F.; Lewis, S. A., Sr.; Storey, J. M.; Domingo, N. & Graves, R. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Regulated and Unregulated Exhaust Emissions Comparison for Three Tier II Non-Road Diesel Engines Operating on Ethanol-Diesel Blends

Description: Regulated and unregulated emissions (individual hydrocarbons, ethanol, aldehydes and ketones, polynuclear aromatic hydrocarbons (PAH), nitro-PAH, and soluble organic fraction of particulate matter) were characterized in engines utilizing duplicate ISO 8178-C1 eight-mode tests and FTP smoke tests. Certification No. 2 diesel (400 ppm sulfur) and three ethanol/diesel blends, containing 7.7 percent, 10 percent, and 15 percent ethanol, respectively, were used. The three, Tier II, off-road engines we… more
Date: November 1, 2005
Creator: Merritt, P. M.; Ulmet, V.; McCormick, R. L.; Mitchell, W. E. & Baumgard, K. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Volatile Organic Compound Concentrations and Emission Rates Measured Over One Year in a New Manufactured House

Description: A study to measure indoor concentrations and emission rates of volatile organic compounds (VOCs), including formaldehyde, was conducted in a new, unoccupied manufactured house installed at the National Institute of Standards and Technology (NIST) campus. The house was instrumented to continuously monitor indoor temperature and relative humidity, heating and air conditioning system operation, and outdoor weather. It also was equipped with an automated tracer gas injection and detection system to… more
Date: September 1, 2004
Creator: Hodgson, Alfred T.; Nabinger, Steven J. & Persily, Andrew K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Volatile organic chemical emissions from structural insulated panel (SIP) materials and implications for indoor air quality

Description: The emissions of volatile organic compounds (VOCs) from structural insulated panel (SIP) materials were investigated. Specimens of newly produced SIPs and associated panel adhesives were obtained from two relatively large manufacturers. Additionally, specimens of the oriented strand board (OSB) used as the inner and outer sheathing and the extruded polystyrene core for the SIP were obtained from one manufacturer. Using small-scale chambers, emissions of formaldehyde, acetaldehyde, acetic acid a… more
Date: September 1, 2003
Creator: Hodgson, Alfred T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Correlations of physical and chemical properties of lanthanide oxides with catalytic behaviors. Progress report, September 1, 1980-August 31, 1981

Description: Using the batch reaction/analysis system that has been described in a previous Progress Report, separate characterization of the behaviors of both La/sub 2/O/sub 3/ and Nd/sub 2/O/sub 3/ for ethanol decomposition have been completed. Investigation of the corresponding properties of Pr/sub 2/O/sub 3/ for this reaction is in progress. In spite of their dissimilar cationic electronic/magnetic properties and differing surface basicities, the catalytic behaviors of La/sub 2/O/sub 3/ and Nd/sub 2/O/s… more
Date: April 1981
Creator: Rosynek, Michael P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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