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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

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

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

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

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

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: 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


Description: Batch processes on a scale of 250 to 300 g of uranium were developed for the production of uranyl oxinate (8quinolinate) and uranyl malonate. Both compounds are insoluble in water and were found to be suitably soluble in pitch. Uranyl oxinate was prepared by the reaction of an aqueous uranyl nitrate solution with an acetic acid solution of oxine (8-quinolirol) at about 80 deg C. Complete precipitation was accomplished by the addition of ammonium hydroxide. Yields of better than 99.5% were obtained. Uranyl malonate was prepared by the reaction of aqueous solutions of sodium malonate and uranyl nitrate at about 80 deg C in 97 to 98% yield. Uranyl 2-ethylhexanoate was prepared by a transesterification reaction from uranyl acetate and 2-ethylhexanoic acid. Yields of 90% were obtained but the process was quite laborious ard time consuming. A metathesis method of preparation was not successful. (auth)
Date: May 1, 1959
Creator: Baxman, H.R.; Jackson, D.D.; Williams, D.L. & Bard, R.J.
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


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

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

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

The Effect of Ring Substitution Position on the Structural Conformation of Mercaptobenzoic Acid Self-Assembled Monolayers on Au(111)

Description: Near edge X-ray absorption fine structure (NEX-AFS) spectroscopy, photoemission spectroscopy (PES) and contact angle measurements have been used to examine the structure and bonding of self-assembled monolayers (SAMs) prepared on Au(111) from the positional isomers of mercaptobenzoic acid (MBA). The isomer of MBA and solvent chosen in SAM preparation has considerable bearing upon film morphology. Carbon K-edge NEXAFS measurements indicate that the monomers of 2-, 3- and 4-MBA have well-defined orientations within their respective SAMs. Monomers of 3- and 4-MBA assume an upright orientation on the Au substrates in monolayers prepared using an acetic acid in ethanol solvent. The aryl ring and carboxyl group of these molecules are tilted from the surface normal by a colatitudal angle of {approx} 30{sup o}. Preparation of 4-MBA SAMs using pure ethanol solvent, a more traditional means of synthesis, had no appreciable effect upon the monomer orientation. Nonetheless, S(2p) PES measurements illustrate that it results in extensive bilayer formation via carboxyl group hydrogen-bonding between 4-MBA monomers. In 2-MBA monolayers prepared using acetic acid/ethanol solvent, the monomers adopt a more prostrate orientation on the Au substrates, in which the aryl ring and carboxyl group of the molecules are tilted {approx} 50{sup o} from the surface normal. This configuration is consistent with an interaction between both the mercaptan sulfur and carboxyl group of 2-MBA with the underlying substrate. S(2p) and C(1s) PES experiments provide supporting evidence for a bidentate interaction between 2-MBA and Au(111).
Date: April 12, 2006
Creator: Lee, J; Willey, T; Nilsson, J; Terminello, L; De Yoreo, J & van Buuren, T
Partner: UNT Libraries Government Documents Department