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Determination of Abraham model solute descriptors for the monomeric and dimeric forms of trans-cinnamic acid using measured solubilities from the Open Notebook Science Challenge

Description: Article on the determination of Abraham model solute descriptors for the monomeric and dimeric forms of trans-cinnamic acid using measured solubilities from the Open Notebook Science Challenge.
Date: September 25, 2014
Creator: Bradley, Jean-Claude; Abraham, M. H. (Michael H.); Acree, William E. (William Eugene); Lang, Andrew S. I. D.; Beck, Samantha N.; Bulger, David A. et al.
Partner: UNT College of Arts and Sciences

Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain Site characterization study. Progress report, January 1, 1995--March 31, 1995

Description: Fluorinated organic acids were utilized in a test study as hydrologic tracers for the Yucca Mountain Project. Fluorinated acids included cinnamic acid; benzoic acid, and toluic acid. Results are discussed pertaining to retention time, elution time, and stability.
Date: May 1, 1995
Creator: Stetzenbach, K. & Farnham, I.
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

Coalification by clay-catalyzed oligomerization of plant monomers

Description: The next step in our systematic examination of the radical cationinitiated dimerization of plant monomers from the D{sub 6}-C{sub 3} pool of shikimic acid metabolites was to study the dimerization of cinnamic acid and its derivatives. In order to do this we needed a radical cation initiator that has a reduction potential greater than that of BAHA (E{sub red} = 1.30 volts), since the electron-withdrawing carboxylate functional group of cinnamates renders them inert to oxidation with BAHA. This problem was solved with the observation that DBAHA tris-(2,4-dibromophenyl)aminium hexachloroantimonate, E{sub red} = 1.74 volts, intiated the radical cation dimerization of methyl 3,4-dimethoxycinnamate.
Date: January 1, 1990
Creator: Orchin, M. & Wilson, R.M.
Partner: UNT Libraries Government Documents Department

Coalification by clay-catalyzed oligomerization of plant monomers

Description: One of the main objectives is to explore the possibility that radical cation Diels-Alder reactions are involved in the biosynthesis of lignans in plants. Two of the most highly sought after classes of lignans are the dibenzocyclooctadienes represented by stegnol and the aryltetralins represented by podophyllotoxin. Both are powerful anticancer agents and have structures that might be assembled from C{sub 6}-C{sub 3} units via radical cation processes. A common feature of both of these molecules is the benzyllic hydroxyl group. The hydroxyl group is cis to the lactone carbonyl carbon. The hypothetical mechanism by which this hydroxyl group might be introduced into the aryltetralins is outlined. We have also begun to study the radical cation Diels-Alder chemistry of cinnamate salts. The preliminary results are described. In an extension of our previous work with tethered cinnamates, we have returned to the tethered molecule and are in the process of reexamining its radical cation Diels-Alder chemistry in the presence of Na{sub 2}CO{sub 3}. We have begun to investigate the radical cation chemistry of polycyclic aromatic hydrocarbons in an effort to find chemistry that will produce the coupling of these aromatic molecules. Our first effort has been to look at naphthalene treated with DBAHA. 2 refs.
Date: January 1, 1990
Creator: Orchin, M. & Wilson, R.M.
Partner: UNT Libraries Government Documents Department