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Solubility of 2-Hydroxybenzoic Acid in Water, 1-Propanol, 2-Propanol, and 2-Propanone at (298.2 to 338.2) K and Their Aqueous Binary Mixtures at 298.2 K

Description: Article discussing the solubility of 2-hydroxybenzoic acid in water, 1-propanol, 2-propanol, and 2-propanone at (298.2 to 338.2) K and their aqueous binary mixtures at 298.2 K.
Date: October 25, 2012
Creator: Fakhree, Mohammad Amin Abolghassemi; Ahmadian, Somaieh; Panahi-Azar, Vahid; Jouyban, Abolghasem & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences

CARBON DIOXIDE AS A FEEDSTOCK.

Description: This report is an overview on the subject of carbon dioxide as a starting material for organic syntheses of potential commercial interest and the utilization of carbon dioxide as a substrate for fuel production. It draws extensively on literature sources, particularly on the report of a 1999 Workshop on the subject of catalysis in carbon dioxide utilization, but with emphasis on systems of most interest to us. Atmospheric carbon dioxide is an abundant (750 billion tons in atmosphere), but dilute source of carbon (only 0.036 % by volume), so technologies for utilization at the production source are crucial for both sequestration and utilization. Sequestration--such as pumping CO{sub 2} into sea or the earth--is beyond the scope of this report, except where it overlaps utilization, for example in converting CO{sub 2} to polymers. But sequestration dominates current thinking on short term solutions to global warming, as should be clear from reports from this and other workshops. The 3500 million tons estimated to be added to the atmosphere annually at present can be compared to the 110 million tons used to produce chemicals, chiefly urea (75 million tons), salicylic acid, cyclic carbonates and polycarbonates. Increased utilization of CO{sub 2} as a starting material is, however, highly desirable, because it is an inexpensive, non-toxic starting material. There are ongoing efforts to replace phosgene as a starting material. Creation of new materials and markets for them will increase this utilization, producing an increasingly positive, albeit small impact on global CO{sub 2} levels. The other uses of interest are utilization as a solvent and for fuel production and these will be discussed in turn.
Date: December 9, 2000
Creator: CREUTZ,C. & FUJITA,E.
Partner: UNT Libraries Government Documents Department

CARBON DIOXIDE AS A FEEDSTOCK.

Description: This report is an overview on the subject of carbon dioxide as a starting material for organic syntheses of potential commercial interest and the utilization of carbon dioxide as a substrate for fuel production. It draws extensively on literature sources, particularly on the report of a 1999 Workshop on the subject of catalysis in carbon dioxide utilization, but with emphasis on systems of most interest to us. Atmospheric carbon dioxide is an abundant (750 billion tons in atmosphere), but dilute source of carbon (only 0.036 % by volume), so technologies for utilization at the production source are crucial for both sequestration and utilization. Sequestration--such as pumping CO{sub 2} into sea or the earth--is beyond the scope of this report, except where it overlaps utilization, for example in converting CO{sub 2} to polymers. But sequestration dominates current thinking on short term solutions to global warming, as should be clear from reports from this and other workshops. The 3500 million tons estimated to be added to the atmosphere annually at present can be compared to the 110 million tons used to produce chemicals, chiefly urea (75 million tons), salicylic acid, cyclic carbonates and polycarbonates. Increased utilization of CO{sub 2} as a starting material is, however, highly desirable, because it is an inexpensive, non-toxic starting material. There are ongoing efforts to replace phosgene as a starting material. Creation of new materials and markets for them will increase this utilization, producing an increasingly positive, albeit small impact on global CO{sub 2} levels. The other uses of interest are utilization as a solvent and for fuel production and these will be discussed in turn.
Date: December 9, 2000
Creator: CREUTZ,C. & FUJITA,E.
Partner: UNT Libraries Government Documents Department

The Syntheses of Amino Substituted Salicylic Acids and Related Compounds

Description: The introduction of the ether linkage into various compounds imparts physiological activity, hence the synthesis of various ether derivatives involving the phenol group seemed to be a possible route to tuberculostatic substances. The compounds reported in this work are to be tested for tuberculostatic properties by Parke, Davis and Company.
Date: 1949
Creator: Gerber, Martin
Partner: UNT Libraries

A study of competitive adsorption of organic molecules onto mineral oxides using DRIFTS

Description: Analysis of DRIFTS spectra was used for a quantitative study of competitive adsorption of myristic and salicylic acids onto kaolinite or {gamma}-alumina. Peaks unique to the ring or the chain were selected and single molecule studies used as calibration. Samples were exposed to hexane solution containing equal molecular quantities of each acid. The surface loading of salicylic acid was not influenced by the presence of myristic acid on either mineral but the maximum loading of myristic acid was decreased (46-50%) by salicylic acid. Displacement of myristic acid from {gamma}-alumina, but not kaolinite, was observed when excess salicylic acid remained in solution. A 25% increase in the maximum loading was observed for kaolinite, but not for{gamma}-alumina. On {gamma}-alumina, after a loading of 1 molecule per nm{sup 2}, increased exposure resulted in salicylic acid adsorption only, this value is approximately the same for salicylic acid adsorption from aqueous solution or for water washed hexane treated samples. Thus a set of sites for adsorption of either acid is indicated together with other energetically less favorable sites, which can be occupied by salicylic, but not by myristic, acid.
Date: February 1, 2010
Creator: Joan E. Thomas, Michael J. Kelley
Partner: UNT Libraries Government Documents Department

Phenylpropanoid compounds and disease resistance in transgenic tobacco with altered expression of L-phenylalanine ammonia-lyase

Description: Article on phenylpropanoid compounds and disease resistance in transgenic tobacco with altered expression of L-phenylalanine ammonia-lyase.
Date: November 22, 2002
Creator: Shadle, Gail L.; Wesley, S. Varsha; Korth, Kenneth L.; Chen, Fang; Lamb, Christopher J. & Dixon, R. A.
Partner: UNT College of Arts and Sciences

15. international conference on plant growth substances: Program -- Abstracts

Description: Since the 14th Conference in Amsterdam in 1991, progress in plant hormone research and developmental plant biology has been truly astonishing. The five ``classical`` plant hormones, auxin, gibberellin, cytokinin, ethylene, and abscisic acid, have been joined by a number of new signal molecules, e.g., systemin, jasmonic acid, salicylic acid, whose biosynthesis and functions are being understood in ever greater detail. Molecular genetics has opened new vistas in an understanding of transduction pathways that regulate developmental processes in response to hormonal and environmental signals. The program of the 15th Conference includes accounts of this progress and brings together scientists whose work focuses on physiological, biochemical, and chemical aspects of plant growth regulation. This volume contains the abstracts of papers presented at this conference.
Date: December 31, 1995
Partner: UNT Libraries Government Documents Department

Synthesis of new high performance lubricants and solid lubricants

Description: In our second year of funding we began the testing phase of a number of new classes of lubricants. Three different testing collaborations have already begun and a fourth one is In the works with Dr. Stephen Hsu of the National Institute of Standards and Technology. Dr. Hsu also plans to test some of the same materials for us that Shell Development is studying. With Dr. Bill Jones of NASA, we are studying the effects of branching an high temperature lubricant properties in perfluoropolyethers, Initially Bill Jones is comparing the lubrication and physical properties of perfluorotetraglyme and the following two spherical perfluoropolyethers, Note that one contains a fluorocarbon chain and the other one contains a fluorocarbon ether chain. The synthesis of these was reported in the last progress report. With Professor Patricia Thiel of Iowa State University, we are working on studies of perfluoromethylene oxide ethers and have prepared a series of four of these polyethers to study in collaboration with her research group. These perfluoromethylene oxide ethers have the best low temperature properties of any known lubricants. Thiel's group is studying their interactions with metals under extreme conditions. Thirdly, we have also begun an Interaction with W. August Birke of Shell Development Company in Houston for whom we have already prepared samples of the chlorine-substituted fluorocarbon polyether lubricants whose structures appear on page 54 of our research proposal. Each of these four structures is thought to have potential as lubricant additives to motor oils. We also have underway syntheses of other fluorine-containing branched ether lubricants. These new materials which are also promising as antifriction additives for motor oils appear ahead of the perfluoro additives as Appendix I to the progress report. Additionally for Birke and Shell Development we have at their request prepared the novel compound perfluoro salicylic acid. ...
Date: April 8, 1993
Creator: Lagow, Richard J.
Partner: UNT Libraries Government Documents Department

Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain Site Characterization Study; Progress report, July 1, 1991--December 31, 1991

Description: Studies continued on organic tracers for use as hydrologic tracers as part of the Yucca Mountain Site Characterization project. Tracers studied include benzoic acids, cinnamic acids, and salicylic acids. The main focus of the work performed during the time period from 07/01/91 to 12/31/91 has been the continuation of (1) LC-MS optimization for tracer identification, (2) batch sorption and degradation studies, (3) neoprene tubing evaluation studies, and (4) soil column evaluation of tracer compounds. All of these areas of research (except perhaps the neoprene tubing evaluation) are ongoing and will continue throughout the coming year.
Date: December 31, 1991
Creator: Dombrowski, T. & Stetzenbach, K.
Partner: UNT Libraries Government Documents Department

Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain Site Characterization Study; Progress report, June 1--December 31, 1990

Description: Ground water tracers are solutes dissolved in or carried by ground water to delineate flow pathways. Tracers provide information on direction and speed of water movement and that of contaminants that might be conveyed by the water. Tracers can also be used to measure effective porosity, hydraulic conductivity, dispersivity and solute distribution coefficients. For most applications tracers should be conservative, that is, move at the same rate as the water and not sorb to aquifer materials. Tracers must have a number of properties to be functional. Regardless of the desired properties, the chemical and physical behavior of a tracer in ground water and the porous medium under study must be understood. Good estimates of tracer behavior can be obtained from laboratory studies. Studies in this proposal will address tracer properties with analytical method development, static sorption and degradation studies and column transport studies, Mutagenicity tests will be performed on promising candidates. The tracers that will be used for these experiments are fluorinated organic acids and other organic compounds that have the chemical and biological stability necessary to be effective in the Yucca Mountain environment. Special emphasis will be placed on compounds that fluoresce or have very large ultraviolet absorption coefficients for very high analytical sensitivity.
Date: December 1990
Creator: Stetzenbach, K. J.
Partner: UNT Libraries Government Documents Department

Enhancing solar photocatalytic detoxification by adsorption of porphyrins onto TiO sub 2

Description: Titanium dioxide (TiO{sub 2}) is a known photocatalyst for solar detoxification of water containing organic contaminants including PCB's and dioxins. Unfortunately, the UV light used by the photocatalyst only comprises about 4% of the strong spectrum. Metalloporphyrins strongly absorb in the visible and near infrared region. Using visible light, we have investigated Ni(II) uroporphyrin (NiUroP), Sn(IV)Cl{sub 2} uroporphyrin (SnUroP) and Sn(IV)Cl{sub 2} tetrakis(p-carboxyphenyl) porphyrin (SnTCPP) as possible enhancers of destruction of a model organic compound, salicylic acid (SA), by means of photosensitization of colloidal TiO{sub 2} particles. All three porphyrins are found to adsorb reversibly onto the colloidal TiO{sub 2} upon variation of pH. Adsorption of porphyrins results in the increased colloidal stability of fine TiO{sub 2} particles in the pH range 5--8. While NiUroP on TiO{sub 2} does not show any enhancement of photodestruction, the adsorption of SnUroP increases the destruction rate compared to that of the bare TiO{sub 2} surface. The effect of ambient oxygen on the observed photolability of the Sn porphyrins and enhancement of photodestruction of SA was also investigated. SnTCPP does not photodecompose upon illumination either in the presence or absence of TiO{sub 2}, but neither does it bind to the photocatalyst at pH 6. At pH 4.5 it adsorbs onto TiO{sub 2} but it also photodecompose at this pH. We are attempting to stabilize the adsorbed porphyrins by adding suitable peripheral substituents onto the porphyrin macrocycle. 27 refs., 6 figs.
Date: January 1, 1991
Creator: Majumder, S. A.; Ondrias, M. R.; Prairie, M. R. & Shelnutt, J. A.
Partner: UNT Libraries Government Documents Department

Bioluminescent reporters for catabolic gene expression and pollutant bioavailability

Description: The application of visualized catabolic nah-gene expression using a luxCDABE gene fusion provides a valuable method to measure quantitatively and specifically naphthalene and salicylate bioavailability. It has been demonstrated that the physiological state of the test culture together with the intrinsic regulation mechanisms of the naphthalene degradation pathway as well as the physiological aspects of the lux gene fusion have to be taken into account. The method presented provides a high potential for in situ bioprocess monitoring. In addition, the results obtained with immobilized cells provide a basis for the development of biosensors for environmental applications in specific pollutant monitoring in waste streams and soil slurry systems but, as a general method, also for more conventional biotechnological process control. 8 refs., 2 figs., 1 tab.
Date: January 1, 1991
Creator: Heitzer, A.; DiGrazia, P.M.; Sayler, G.S. (Tennessee Univ., Knoxville, TN (United States). Center for Environmental Biotechnology) & Burlage, R.S. (Oak Ridge National Lab., TN (United States))
Partner: UNT Libraries Government Documents Department

Enhancement of solar photocatalytic detoxification by adsorption of porphyrins onto TiO sub 2

Description: Titanium dioxide (TiO{sub 2}) is a photocatalyst for solar detoxification of water containing organic contaminants such as solvents, PCB's, dioxins, pesticides, and dyes. Unfortunately, the ultraviolet (UV) energy used by TiO{sub 2} ({lambda}<400 nm) only comprises about 4% of the solar spectrum. One way of enhancing the efficiency of solar detoxification technologies is to utilize a larger portion of the solar spectrum to initiate the Tio{sub 2}- catalyzed detoxification chemistry. Metalloporphyrins strongly absorb visible and near infrared radiation. By utilization of a process called photosensitization, adsorption of these dyes onto TiO{sub 2} can enable a much broader portion of the solar spectrum to be used. Photosensitization relies upon the ability of the dye molecule to absorb more of the solar energy than bare TiO{sub 2} and to interact electronically with the TiO{sub 2} surface in such a way as to initiate TiO{sub 2}-based redox photochemistry using the dye-absorbed energy. 16 refs., 7 figs.
Date: January 1, 1991
Creator: Majumder, S.A.; Ondrias, M.R. (New Mexico Univ., Albuquerque, NM (United States). Dept. of Chemistry); Prairie, M.R. (Sandia National Labs., Albuquerque, NM (United States)) & Shelnutt, J.A. (New Mexico Univ., Albuquerque, NM (United States). Dept. of Chemistry Sandia National Labs., Albuquerque, NM (United States))
Partner: UNT Libraries Government Documents Department

Research in radiobiology. Annual report of work in progress in the internal irradiation program

Description: The toxicity, retention, biological effects, distribution, decorporation and measuring techniques of radionuclides are discussed. Calculations of trabecular bone formation rates from tetracycline labeling is included. The characteristics of trabecular bone in the Rhesus monkey are discussed. Studies on the early retention and distribution of radium 224 in beagles are included. Studies on the decorporation of plutonium and americium in dogs by DTPA and salicylic acid are presented.
Date: March 31, 1979
Partner: UNT Libraries Government Documents Department

Mixed ligand chelate therapy for plutonium and toxic metals from energy power production. Progress report, October 15, 1978-October 14, 1979

Description: It is shown that a mixed ligand chelate (MLC) is superior to that of the primary chelate alone for the decorporation of monomeric plutonium. Thus, EDTA plus Tiron reduces the level of Pu in the skeleton to about 40% less than that of EDTA alone when treatment was begun two hrs post /sup 239/Pu. However, DTPA alone was still superior to EDTA/Tiron under the given experimental conditions. However, this appears to be due to the rapid metabolic destruction of secondary chelants such as Tiron and similar bi-dentate derivatives of catechol and salicylates. Investigations are under way to improve such MLC's by the use of metabolic inhibitors to increase the plasma concentrations and residence times of the secondary chelants. In addition, MLC's consisting of metabolically stable chelants are undergoing testing. Therapy of cadmium poisoned mice by single and mixed chelants is also under study. A molar ratio of EDTA to Cd of 1.6 reduces the mortality by half of female mice given 5 min (i.p.) post supralethal doses of CdCl/sub 2/, while a molar ratio of 4.7 for 2, 3-dimercaptopropanol-1-sulfonate (DMPS) is required. No protection is observed with penicillamine (PA) or salicylates (SA) alone. However, combinations of EDTA with both PA and DMPS or SA and DMPS afford protection under conditions (30 min post Cd) where the individual chelants are ineffective. Automated potentiometric titrations are utilized to detect MLC formation and to evaluate their stability. The titration data are used as a screening procedure to ascertain whether a given chelant combination is worth testing in vivo.
Date: July 12, 1979
Creator: Schubert, J.
Partner: UNT Libraries Government Documents Department