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Effect of Indole-3-Acetic Acid on the Nucleic Acids of Synchronous Cultures of Chlorella Pyrenoidosa

Description: It was the purpose of this study to investigate the effect of various concentrations of IAA on the nucleic acids of Chlorella pyrenoidosa TX 7-11-05. The time during the life cycle when the greatest effect occurred was investigated by the use of synchronous cultures.
Date: May 1972
Creator: Peterson, James Arthur
Partner: UNT Libraries

A PreliminaryReport on the Mechanism of the Decomposition ofDiacetyl Peroxide in Acetic Acid

Description: The decomposition of diacetyl peroxide in acetic acid-2-C{sup 14} has been studied, The activity of the products in general confirmed the mechanism of the reaction as proposed by Kharasch and Gladstone, The presence and distribution of activity in the methyl acetate produced in this reaction is not explained by the previously proposed mechanism. There was no appreciable exchange of acetic acid and diacetyl peroxide under the conditions of the reaction. Essentially no exchange of methyl acetate and acetic acid was observed when those reagents mere heated at 100 for five hours.
Date: December 29, 1949
Creator: Fry, A.J.; Tolbert, B.M. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department


Description: The flowsheet visualized from development work thus far for final plutonium recovery and purification will accept as feed a Purex partition stream without feed adjustment beyond the usual reoxidation. Extraction with trilaurylamine at approximately 0.3M appears suitable for 20 to 60 g Pu/liter product from 0.5 to 2 g Pu/liter feed. Scrubbing with either ((2 M or))2 M HNO/ sub 3/ is possible. Acetic acid is at present the first choice for stripping agent, with oil-soluble and aqueous-soluble organic reductants as alternates. (auth)
Date: May 24, 1961
Creator: Coleman, C.F.
Partner: UNT Libraries Government Documents Department

The Partitioning of Acetic, Formic, and Phosphoric Acids Between Liquid Water and Steam

Description: The chemical carryover of impurities and treatment chemicals from the boiler to the steam phase, and ultimately to the low-pressure turbine and condenser, can be quantified based on laboratory experiments preformed over ranges of temperature, pH, and composition. The two major assumptions are that thermodynamic equilibrium is maintained and no deposition, adsorption or decomposition occurs. The most recent results on acetic, formic and phosphoric acids are presented with consideration of the effects of hydrolysis and dimerization reactions. Complications arising from thermal decomposition of the organic acids are discussed. The partitioning constants for these acids and other solutes measured in this program have been incorporated into a simple thermodynamic computer code that calculates the effect of chemical and mechanical carryover on the composition of the condensate formed to varying extents in the water/steam cycle.
Date: June 22, 1999
Creator: Gruszkiewicz, M. S.; Marshall, S. L.; Palmer, D. A. & Simonson, J. M.
Partner: UNT Libraries Government Documents Department

Abraham Model Correlations for Estimating Solute Transfer of Neutral Molecules into Anhydrous Acetic Acid from Water and from the Gas Phase

Description: Article on Abraham model correlations for estimating solute transfer of neutral molecules into anhydrous acetic acid from water and from the gas phase.
Date: September 1, 2015
Creator: Stovall, Dawn M.; Schmidt, Amber; Dai, Colleen; Zhang, Shoshana; Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
Partner: UNT College of Arts and Sciences

Degradation of Isotopic Lactate and Acetate

Description: A scheme of glucose degradation has been validated by the use of intermediates of known isotopic composition. In this scheme: glucose {yields} lactic acid {yields} CO{sub 2} (C-3,4) + acetic acid {yields} CO{sub 2} (C-2,5) + acetone {yields} iodoform (C-1,6) + acetate (C-1,6; 2,5), it was found that (a) in the oxidation of lactic acid, approximately 4.7% of the acetic acid was oxidized to CO{sub 2}; and (b) under the conditions prescribed, BaCO{sub 3} from the degradation of Ba acetate contained approximately 1.5% of the activity of the methyl group.
Date: February 24, 1948
Creator: Aronoff, S.; Haas, V.A. & Fries, B.A.
Partner: UNT Libraries Government Documents Department

PhyloChip microarray analysis reveals altered gastrointestinal microbial communities in a rat model of colonic hypersensitivity

Description: Irritable bowel syndrome (IBS) is a chronic, episodic gastrointestinal disorder that is prevalent in a significant fraction of western human populations; and changes in the microbiota of the large bowel have been implicated in the pathology of the disease. Using a novel comprehensive, high-density DNA microarray (PhyloChip) we performed a phylogenetic analysis of the microbial community of the large bowel in a rat model in which intracolonic acetic acid in neonates was used to induce long lasting colonic hypersensitivity and decreased stool water content and frequency, representing the equivalent of human constipation-predominant IBS. Our results revealed a significantly increased compositional difference in the microbial communities in rats with neonatal irritation as compared with controls. Even more striking was the dramatic change in the ratio of Firmicutes relative to Bacteroidetes, where neonatally irritated rats were enriched more with Bacteroidetes and also contained a different composition of species within this phylum. Our study also revealed differences at the level of bacterial families and species. The PhyloChip is a useful and convenient method to study enteric microflora. Further, this rat model system may be a useful experimental platform to study the causes and consequences of changes in microbial community composition associated with IBS.
Date: December 1, 2010
Creator: Nelson, T.A.; Holmes, S.; Alekseyenko, A.V.; Shenoy, M.; DeSantis, T.; Wu, C.H. et al.
Partner: UNT Libraries Government Documents Department


Description: Ruthenium in uranyl nitrate solutions from the Purex Process was adsorbed by the solid residue that remains when the solutions are concentrated by evaporation after treatment with thiocarbanilide and thioacetarnide. Other chemicals were tested and the results are summarized. (auth)
Date: June 1, 1958
Creator: Prohaska, C.A.
Partner: UNT Libraries Government Documents Department

An Isotope Effect in a Simple Chemical Reaction

Description: It has been found that the carbon dioxide obtained from the decarboxylation of singly-carboxyl labeled malonic acid is impoverished in the C{sup 14} label and that the acetic acid formed is correspondingly enriched.
Date: July 13, 1948
Creator: Yankwich, Peter E. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department

Characterization of the Sources and Concentrations of Formaldehyde and other volatile organic compounds in four new manufactured houses

Description: The concentrations of formaldehyde, 52 individual volatile organic compounds (VOCs) and total VOCs (TVOC) were measured in four new manufactured houses on three occasions over a period of approximately nine months following completion of their construction. The houses were furnished, but unoccupied, model homes produced by a single U.S. manufacturer. Several of the houses incorporated interior finish materials with lower VOC emissions than standard materials. One house had a modified ventilation system. Ventilation rates were measured concurrently with the collection of air samples. A steady-state mass-balance model was used to calculate the area-specific emission rates of the target compounds and TVOC. The emissions of formaldehyde and VOCs from a specimen of plywood used as the floor sheeting were additionally quantified. The median formaldehyde concentration in the four houses was 37 parts-per-billion ( ppb). The formaldehyde concentrations were all less than the most restrictive guideline for this compound of 50 ppb. The concentrations of many of the target VOCs were low. Thirty-one of the VOCs had median concentrations that were at or below 1 ppb. Seven of the compounds were among the most abundant VOCs in all four houses. These compounds were alpha-pinene, beta-pinene, 3-carene, ethylene glycol, hexanal, 2-butanone, and acetic acid. The concentrations of the aldehydes, hexanal, octanal and nonanal, in the four houses were either near or exceeded their respective odor thresholds. The concentrations of acetic acid increased with time. In the final sampling period, the odor threshold for acetic acid was exceeded in all of the houses. The range of TVOC concentrations in the four houses was 0.8 to 3 mg m{sup -3}, with a median value of 1.6 mg m{sup -3}. These concentrations were somewhat lower than TVOC concentrations previously measured in several new site-built houses, and the median concentration was only about twice the typical value ...
Date: September 1, 1998
Creator: Hodgson, A.T.; Beal, D. & Chandra, S.
Partner: UNT Libraries Government Documents Department

Microbial ecology of thermophilic anaerobic digestion. Final report

Description: This grant supported research on methanogenic archaea. The two major areas that were supported were conversion of acetic acid to methane and nitrogen fixation by Methanosarcina. Among the achievements of this research were the isolation of novel methanogenic cultures, elucidation of the pathways from acetate to methane, description of a specific DNA-binding complex in nitrogen fixing methanogens, and demonstration of an alternative nitrogenase in Methanosarcina.
Date: April 15, 2000
Creator: Zinder, Stephen H.
Partner: UNT Libraries Government Documents Department

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 products, with yields under most conditions of 20-30% with respect to ozone consumed. Acetaldehyde, acetone, glycolaldehyde, formic acid and acetic acid were each also detected for two or three of the products. Immediately upon mixing of reactants, a scanning mobility particle sizer detected particle nucleation events that were followed by a significant degree of ultrafine particle growth. The production of secondary gaseous pollutants and particles depended primarily on the ozone level and was influenced by other parameters such as the air-exchange rate. Hydroxyl radical concentrations in the range 0.04-200 x 10{sup 5} molecules cm{sup -3} were measured. OH concentrations were observed to vary strongly with residual ozone level in the chamber, which was in the range 1-25 ppb, as is consistent with expectations from a simplified kinetic model. In a separate test, we exposed the dry residue of two products to ozone in the chamber and observed the formation of gas-phase and particle-phase secondary oxidation products.
Date: October 1, 2005
Creator: Destaillats, Hugo; Lunden, Melissa M.; Singer, Brett C.; Coleman,Beverly K.; Hodgson, Alfred T.; Weschler, Charles J. et al.
Partner: UNT Libraries Government Documents Department


Description: This project, which was sponsored by the U.S. Department of Energy (DOE) under the Clean Coal Technology Program to demonstrate the production of methanol from coal-derived synthesis gas (syngas), has completed the 69-month operating phase of the program. The purpose of this Final Report for the ''Commercial-Scale Demonstration of the Liquid Phase Methanol (LPMEOH{trademark}) Process'' is to provide the public with details on the performance and economics of the technology. The LPMEOH{trademark} Demonstration Project was a $213.7 million cooperative agreement between the DOE and Air Products Liquid Phase Conversion Company, L.P. (the Partnership). The DOE's cost share was $92,708,370 with the remaining funds coming from the Partnership. The LPMEOH{trademark} demonstration unit is located at the Eastman Chemical Company (Eastman) chemicals-from-coal complex in Kingsport, Tennessee. The technology was the product of a cooperative development effort by Air Products and Chemicals, Inc. (Air Products) and DOE in a program that started in 1981. Developed to enhance electric power generation using integrated gasification combined cycle (IGCC) technology, the LPMEOH{trademark} Process is ideally suited for directly processing gases produced by modern coal gasifiers. Originally tested at the Alternative Fuels Development Unit (AFDU), a small, DOE-owned process development facility in LaPorte, Texas, the technology provides several improvements essential for the economic coproduction of methanol and electricity directly from gasified coal. This liquid phase process suspends fine catalyst particles in an inert liquid, forming a slurry. The slurry dissipates the heat of the chemical reaction away from the catalyst surface, protecting the catalyst, and allowing the methanol synthesis reaction to proceed at higher rates. The LPMEOH{trademark} Demonstration Project accomplished the objectives set out in the Cooperative Agreement with DOE for this Clean Coal Technology project. Overall plant availability (defined as the percentage of time that the LPMEOH{trademark} demonstration unit was able to operate, with the exclusion ...
Date: June 1, 2003
Creator: Heydorn, E.C.; Diamond, B.W. & Lilly, R.D.
Partner: UNT Libraries Government Documents Department

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 and other VOCs from SIPs, OSB and polystyrene were measured over a period of four months and from the adhesives over two months. SIP specimens overlaid by gypsum board panels were also tested over four months. The predominant VOCs emitted by the SIPs included acetic acid, pentanal, hexanal and styrene. The emissions of formaldehyde and acetaldehyde were relatively low. Acetic acid and the aldehydes derived from the OSB, while styrene derived from the polystyrene. One of the SIPs emitted toluene and methyl acetate. The adhesives primarily emitted a mixture of hydrocarbons. The emission rates of most VOCs from the SIP/gypsum board assemblies were approximately the same or higher than their respective emission rates from the unfinished SIPs. Modeling using VOC emission factors obtained for the SIP/gypsum board assemblies demonstrated the potential for SIP materials to degrade indoor air quality in houses. A field study to investigate VOC concentrations and emission rates in SIP houses relative to closely matched conventionally constructed houses is necessary to determine the actual impacts of SIPs. If significant impacts are observed, to it may be desirable to develop control measures to reduce the emissions of VOCs from SIPs, such as the substitution of lower emitting materials or the use of vapor diffusion barriers.
Date: September 1, 2003
Creator: Hodgson, Alfred T.
Partner: UNT Libraries Government Documents Department

T2LBM Version 1.0: Landfill bioreactor model for TOUGH2

Description: The need to control gas and leachate production and minimize refuse volume in landfills has motivated the development of landfill simulation models that can be used by operators to predict and design optimal treatment processes. T2LBM is a module for the TOUGH2 simulator that implements a Landfill Bioreactor Model to provide simulation capability for the processes of aerobic or anaerobic biodegradation of municipal solid waste and the associated flow and transport of gas and liquid through the refuse mass. T2LBM incorporates a Monod kinetic rate law for the biodegradation of acetic acid in the aqueous phase by either aerobic or anaerobic microbes as controlled by the local oxygen concentration. Acetic acid is considered a proxy for all biodegradable substrates in the refuse. Aerobic and anaerobic microbes are assumed to be immobile and not limited by nutrients in their growth. Methane and carbon dioxide generation due to biodegradation with corresponding thermal effects are modeled. The numerous parameters needed to specify biodegradation are input by the user in the SELEC block of the TOUGH2 input file. Test problems show that good matches to laboratory experiments of biodegradation can be obtained. A landfill test problem demonstrates the capabilities of T2LBM for a hypothetical two-dimensional landfill scenario with permeability heterogeneity and compaction.
Date: May 22, 2001
Creator: Oldenburg, Curtis M.
Partner: UNT Libraries Government Documents Department

Continuous countercurrent chromatographic separator for the purification of sugars from biomass hydrolyzate. Final project report, July 1, 1996--September 30, 1997

Description: Production of pure sugars is required to enable production of fuels and chemicals from biomass feedstocks. Hydrolysis of cellulose and hemicellulose (principal constituents of biomass) produces sugars that can be utilized in various fermentation process to produce valuable chemicals. Unfortunately, the hydrolysis process also liberates chemicals from the biomass that can be toxic to the fermenting organisms. The two primary toxic components of biomass hydrolyzate are sulfuric acid (catalyst used in the hydrolysis) and acetic acid (a component of the feed biomass). In the standard batch chromatographic separation of these three components, sugar elutes in the middle. Batch chromatographic separations are not practical on a commercial scale, because of excess dilution and high capital costs. Because sugar is the {open_quotes}center product,{close_quotes} a continuous separation would require two costly binary separators. However, a single, slightly larger separator, configured to produce three products, would be more economical. This FIRST project develops a cost-effective method for purifying biomass hydrolyzate into fermentable sugars using a single continuous countercurrent separator to separate this ternary mixture.
Date: December 1, 1997
Creator: Wooley, R. J.
Partner: UNT Libraries Government Documents Department

Reaction mechanism studies of unsaturated molecules using photofragment translational spectroscopy

Description: A number of molecules have been studied using the technique of photofragment translational spectroscopy. In Chapter One a brief introduction to the experimental technique is given. In Chapter Two the infrared multiphoton dissociation (IRMPD) of acetic acid is discussed. Carbon dioxide and methane were observed for the first time as products from dissociation under collisionless conditions. Chapter Three relates an IRMPD experiment of hexafluoropropene. The predominant channel produces CFCF{sub 3} or C{sub 2}F{sub 4} and CF{sub 2}, with the heavier species undergoing further dissociation to two CF{sub 2} fragments. In Chapter Four the ultraviolet (UV) dissociation of hexafluoropropene is investigated. Chapter Five explores the IRMPD of octafluoro-1-butene and octafluoro-2-butene.
Date: May 1, 1996
Creator: Longfellow, C.A.
Partner: UNT Libraries Government Documents Department

BNL Building 650 lead decontamination and treatment feasibility study. Final report

Description: Lead has been used extensively at Brookhaven National Laboratory (BNL) for radiation shielding in numerous reactor, accelerator and other research programs. A large inventory of excess lead (estimated at 410,000 kg) in many shapes and sizes is currently being stored. Due to it`s toxicity, lead and soluble lead compounds are considered hazardous waste by the Environmental Protection Agency. Through use at BNL, some of the lead has become radioactive, either by contamination of the surface or through activation by neutrons or deuterons. This study was conducted at BNL`s Environmental and Waste Technology Center for the BNL Safety and Environmental Protection Division to evaluate feasibility of various treatment options for excess lead currently being stored. The objectives of this effort included investigating potential treatment methods by conducting a review of the literature, developing a means of screening lead waste to determine the radioactive characteristics, examining the feasibility of chemical and physical decontamination technologies, and demonstrating BNL polyethylene macro-encapsulation as a means of treating hazardous or mixed waste lead for disposal. A review and evaluation of the literature indicated that a number of physical and chemical methods are available for decontamination of lead. Many of these techniques have been applied for this purpose with varying degrees of success. Methods that apply mechanical techniques are more appropriate for lead bricks and sheet which contain large smooth surfaces amenable to physical abrasion. Lead wool, turnings, and small irregularly shaped pieces would be treated more effectively by chemical decontamination techniques. Either dry abrasion or wet chemical methods result in production of a secondary mixed waste stream that requires treatment prior to disposal.
Date: October 1, 1995
Creator: Kalb, P.D.; Cowgill, M.G. & Milian, L.W.
Partner: UNT Libraries Government Documents Department

Influence of surface defects and local structure on acid/base properties and oxidation pathways over metal oxide surfaces. Final report, June 1990--January 1997

Description: This final report covers work done during project period one and project period two. All the work in project period one was focused on the selective oxidation of oxygenated hydrocarbons over the SnO{sub 2}(110) single crystal surface. In project period two, the emphasis was on the acid/base properties of SnO{sub 2}(110) as well as two different Cu{sub 2}O single crystal surfaces. Prior to the summary of results, a description of these different surfaces is given as background information. Results are described for the dissociation and reaction of Bronsted acids (methanol, formic acid, water, formaldehyde, acetone, propene, acetic acid, and carbon monoxide). Results from project period two include: ammonia adsorption, CO{sub 2} adsorption, propene adsorption and oxidation, with tin oxides; complimentary work with copper oxides; and STM investigations.
Date: December 31, 1997
Creator: Cox, D.F.
Partner: UNT Libraries Government Documents Department

Refining of fossil resin flotation concentrate from western coal. Final report

Description: During the past several years, significant research efforts have been made to develop process technology for the selective flotation of fossil resin from western coals. As a result of these efforts, several new flotation technologies have been developed. Operation of a proof-of-concept continuous flotation circuit showed the selective flotation process to be sufficiently profitable to justify the development of a fossil resin industry. However, little attention has been given to the refining of the fossil resin flotation concentrate although solvent refining is a critical step for the fossil resin to become a marketable product. In view of this situation, DOE funded this two-year project to evaluate the following aspects of the fossil resin refining technology: 1) Characterization of the fossil resin flotation concentrate and its refined products; 2) Kinetics of fossil resin extraction; 3) Effects of operating variables on solvent extraction; 4) Extraction solvents; 5) Proof-of-concept continuous refining tests; and 6) Technical and economic analysis. The results from this research effort have led to the following conclusions: Hexane- or heptane-refined fossil resin has a light-yellow color, a melting point of 140 - 142{degrees}C, a density of 1.034 gram/cm, and good solubility in nonpolar solvents. Among the four solvents evaluated (hexane, heptane, toluene and ethyl acetate), hexane is the most appropriate solvent based on overall technical and economic considerations. Batch extraction tests and kinetic studies suggest that the main interaction between the resin and the solvent is expected to be the forces associated with solvation phenomena. Temperature has the most significant effect on extraction rate. With hexane as the solvent, a recovery of 90% cam be achieved at 50{degrees}C and 10% solids concentration with moderate agitation for 1 hour.
Date: February 16, 1995
Creator: Jensen, G.F. & Miller, J.D.
Partner: UNT Libraries Government Documents Department

Effect of Organic Acid Additions on the General and Localized Corrosion Susceptibility of Alloy 22 in Chloride Solutions

Description: Electrochemical studies such as cyclic potentiodynamic polarization (CPP) and electrochemical impedance spectroscopy (EIS) were performed to determine the corrosion behavior of Alloy 22 (N06022) in 1M NaCl solutions at various pH values from acidic to neutral at 90 C. All the tested material was wrought Mill Annealed (MA). Tests were also performed in NaCl solutions containing weak organic acids such as oxalic, acetic, citric and picric. Results show that the corrosion rate of Alloy 22 was significantly higher in solutions containing oxalic acid than in solutions of pure NaCl at the same pH. Citric and picric acids showed a slightly higher corrosion rate, and acetic acid maintained the corrosion rate of pure chloride solutions at the same pH. Organic acids revealed to be weak inhibitors for crevice corrosion. Higher concentration ratios, compared to nitrate ions, were needed to completely inhibit crevice corrosion in chloride solutions. Results are discussed considering acid dissociation constants, buffer capacity and complex formation constants of the different weak acids.
Date: August 28, 2007
Creator: Carranza, R M; Giordano, C M; Rodr?guez, M A; Ilevbare, G O & Rebak, R B
Partner: UNT Libraries Government Documents Department


Description: Most of the tasks on the project have successfully been completed and reported. A 12 month no-cost extension has been requested to complete the remaining tasks. This report summarizes the accomplishments of the first six months of the no-cost extensions period. The acetic acid extraction showed that acetic acid has more effect on the extraction of the ternary catalyst (LNK) ions than water. Based on the extraction results, the order of the recovery capability of Na{sub 2}CO{sub 3} using acetic acid, sulfuric acid and water extractions is sulfuric acid {ge} acetic acid > water; the order for K{sub 2}CO{sub 3} is sulfuric acid > water >acetic acid; and the order for Li{sub 2}CO{sub 3} is acetic acid > sulfuric acid >water. A process flowsheet for the catalyst recovery process was proposed based on the results. Scanning electron microscopy (SEM) studies showed most of the particles (coal) appear amorphous. Some coal particles are as large as 50-60 {micro}m, but most are smaller. One can also easily see a few crystalline particles (10-20 {micro}m) with sharp facets and corners. The electron micrographs of gasified char samples (reactor-aged) of the LNKcoal mixture showed that a dramatic change is obvious in the morphology and crystallinity of the sample and is consistent with the results obtained from the x-ray diffraction studies. XRD studies of reactor-aged samples showed a substantial increase in the sample crystallinity (due to the gasification of amorphous carbon). The eutectic salt presumably mostly converted to sulfates.
Date: March 31, 2001
Creator: Sheth, Atul & Sastry, Chandramouli
Partner: UNT Libraries Government Documents Department