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Project "A" Final Summary Report

Description: Report discussing the results of Project "A," which had three main components: "Effect of P2O3 Concentration on the Distribution Coefficient for Uranium Between Crude Phosphoric Acid and O.P.P.A.," "Effect of Chloride Concentration in Phosphoric Acid on the Distribution Coefficient for Uranium Between O.P.P.A. and Phosphoric Acid," and "The Use of Di-Isobutyl Carbinol in the Preparation of a Solvent to Extract Uranium from Phosphoric Acid (N.P.P.A.)."
Date: January 4, 1954
Creator: Wilkinson, G. E.
Partner: UNT Libraries Government Documents Department


Description: High resolution proton magnetic resonance spectra are presented for 48 trial phosphates and related phosphorus compouds. Chemical shifts, spin-spin coupling Constants, and spectral analyses are reported for compounds of interest in solvent extraction technology. (auth)
Date: June 1, 1960
Creator: Shuler, W.E. & Axtmann, R.C.
Partner: UNT Libraries Government Documents Department

The Neutral Organophorus Compounds as Extractants

Description: The properties of neutral organophosphorus compounds as solvents, in particular, solvents which form solvation complexes with inorganic molecules, were considered. Physical properties of the compounds are described. Phospnines, phosphine oxides, phosphinates, phosphonates, and phosphates were studied with respect to complex formation with inorganic compounds. The extraction of mineral acids by these compounds is discussed. (M.C.G.)
Date: October 15, 1962
Creator: Burger, L. L.
Partner: UNT Libraries Government Documents Department


Description: A brief general discussion is given of the nomenclature and types of organophosphorus compounds that could be useful for aqueous processing of irradiated fuels and byproduct isotopes. Comments are made on the use of compounds that might give substantial process gains even though the compounds may not be readily available. Application of alternative extractant-diluent systems is examined for simultaneous recovery of U and Pu (Purex), simuitaneous recovery of U/sup 233/ and Th (Thorex), and recovery of U alone (enriched uranium or 25''). Recovery of by-product elements such as Pm, Am, and Cm is discussed with particular emphasis on the possible use of bifunctional organophosphorus extractants. A discussion is given of a number of speciflc types of compounds that are of interest to future investigations. These compounds are chosen on the basis of unusual structure, possible effects on synergistic relationships, interesting theoretical possibilities, and practical potential. A brief discussion is given of the powerful synthetic techniques developed over the last few years that make such a wide range of compounds potentially available for study. (auth)
Date: March 1, 1963
Creator: Siddall, III, T H
Partner: UNT Libraries Government Documents Department

The Path of Carbon in Photosynthesis. XVII. Phosphorus Compoundsas Intermediates in Photosynthesis

Description: Studies of carbon dioxide fixation in green plants using the C{sup 14} isotope have shown that in very short times phosphoglyceric acid contains most of the radioactivity. The tracer is present almost entirely in the carboxyl group. The importance of organic phosphates in the subsequent metabolism of phosphoglyceric acid can be seen from the accompanying photographs.
Date: July 8, 1952
Creator: Buchanan, J.G.; Bassham, J.A.; Benson, A.A.; Bradley, D.F.; Calvin, M.; Daus, L.L. et al.
Partner: UNT Libraries Government Documents Department

Physical properties of Li ion conducting polyphosphazene based polymer electrolytes

Description: We report a systematic study of the transport properties and the underlying physical chemistry of some polyphosphazene (PPhz)-based polymer electrolytes. We synthesized MEEP and variants which employed mixed combinations of different length oxyethylene side-chains. We compare the conductivity and ion-ion interactions in polymer electrolytes obtained with lithium triflate and lithium bis(trifluoromethanesulfonyl)imide (TFSI) salts added to the polymer. The combination of the lithium imide salt and MEEP yields a maximum conductivity of 8 x 10{sup -5} {Omega}{sup -1} cm{sup -1} at room temperature at a salt loading of 8 monomers per lithium. In one of the mixed side-chain variations, a maximum conductivity of 2 x 10{sup -4} {Omega}{sup -1} cm{sup -1} was measured at the same molar ratio. Raman spectral analysis shows some ion aggregation and some polymer - ion interactions in the PPhz-LiTFSI case but much less than observed with Li CF{sub 3}SO{sub 3}. A sharp increase in the Tg as salt is added corresponds to concentrations above which the conductivity significantly decreases and ion associations appear.
Date: December 31, 1996
Creator: Sanderson, S.; Zawodzinski, T.; Hermes, R.; Davey, J. & Dai, Hongli
Partner: UNT Libraries Government Documents Department

Excitations and possible bound states in the S = {1/2} alternating chain compound (VO){sub 2}P{sub 2}O{sub 7}

Description: Magnetic excitations in an array of (VO){sub 2}P{sub 2}O{sub 7} single crystals have been measured using inelastic neutron scattering. Until now, (VO){sub 2}P{sub 2}O{sub 7} has been thought of as a two-leg antiferromagnetic Heisenberg spin ladder with chains running in the a-direction. The present results show unequivocally that (VO){sub 2}P{sub 2}O{sub 7} is best described as an alternating spin-chain directed along the crystallographic b-direction. In addition to the expected magnon with magnetic zone-center energy gap {Delta} = 3.1 meV, a second excitation is observed at an energy just below 2{Delta}. The higher mode may be a triplet two-magnon bound state. Numerical results in support of bound modes are presented.
Date: July 30, 1997
Creator: Tennant, D.A.; Nagler, S.E. & Sales, B.C.
Partner: UNT Libraries Government Documents Department

Redox behavior of europium in the Preyssler heteropolyanion [EuP{sub 5}W{sub 30}O{sub 110}]{sup 12-}

Description: In aqueous, mineral-acid electrolytes, the cyclic voltammetry of the europium- exchanged Preyssler heteropolyanion, [Eu{sup III}P{sub 5}W{sub 30}O{sub 110}]{sup 12-}, is unique among all the other trivalent-lanthanide-exchanged anions, [Ln{sup III}P{sub 5}W{sub 30}O{sub 110}]{sup 12-} for Ln {triple_bond} Ce-Lu. All [LnP{sub 5}W{sub 30}O{sub 110}]{sup 12-}, including Eu, form heteropoly blues upon reduction. In order to obtain insights about this issue, we conducted in situ Eu L{sub 3}-edge XANES (X-ray absorption near edge structure) spectroelectrochemical experiments on an aqueous solution of [EuP{sub 5}W{sub 30}O{sub 110}]{sup 12-} (5.5 mM) in a supporting electrolyte of 1 M H{sub 2}SO{sub 4} at two extreme potentials. The results demonstrate that the Eu{sup III} ion in the colorless Preyssler anion solution at open circuit potential (+0.21 V vs Ag/AgCl) is electroactive and is reduced to Eu{sup II} in the resulting dark blue solution from constant-potential bulk electrolysis at -0.55 V vs Ag/AgCl. This unusual redox behavior of [EuP{sub 5}W{sub 30}O{sub 110}]{sup 12-} may be of technological importance in the area of oxidation catalysis.
Date: August 1, 1997
Creator: Antonio, M.R. & Soderholm, L.
Partner: UNT Libraries Government Documents Department

The Metabolism of 2-Caroboxy-4-Ketopentitol Diphosphate

Description: 2-Carboxy-4-ketopentitol is converted enzymatically by a cell-free preparation from spinach leaves into a substance undergoing acid-lactone interconversion. This substance has no phosphate or letone group and is probably a dicarboxylic, six-carbon sugar acid or the saccharic or saccharinic acid type. The significance of these findings with regard to the metabolic role of 2-carboxy-4-ketopentitol diphosphate is discussed.
Date: July 15, 1958
Creator: Moses, V. & Calvin, M.
Partner: UNT Libraries Government Documents Department

Intelligent Signal Processing for Detection System Optimization

Description: A wavelet-neural network signal processing method has demonstrated approximately tenfold improvement over traditional signal-processing methods for the detection limit of various nitrogen and phosphorus compounds from the output of a thermionic detector attached to a gas chromatograph. A blind test was conducted to validate the lower detection limit. All fourteen of the compound spikes were detected when above the estimated threshold, including all three within a factor of two above the threshold. In addition, two of six spikes were detected at levels of 1/2 the concentration of the nominal threshold. Another two of the six would have been detected correctly if we had allowed human intervention to examine the processed data. One apparent false positive in five nulls was traced to a solvent impurity, whose presence was subsequently identified by analyzing a solvent aliquot evaporated to 1% residual volume, while the other four nulls were properly classified. We view this signal processing method as broadly applicable in analytical chemistry, and we advocate that advanced signal processing methods should be applied as directly as possible to the raw detector output so that less discriminating preprocessing and post-processing does not throw away valuable signal.
Date: December 5, 2004
Creator: Fu, C. Y.; Petrich, L. I.; Daley, P. F. & Burnham, A. K.
Partner: UNT Libraries Government Documents Department

Phosphorus Turnover and Photosynthesis

Description: The participation of phosphorus in biological oxidation-reduction reactions of the type found in glycolysis ADP + PO{sub 4}H{sup -} + 3-phosphoglyceraldehyde + DPN{sup +} = 3-phosphoglycerate{sup -} + 2H{sup +} + DPNH + ATP has suggested theories in which similar reactions are proposed for photosynthesis. In these theories the reducing power of photosynthesis is utilized not only for reduction of carbon dioxide but also, by means of coupled oxidations, for the generation of high-energy phosphate bonds, or in the last reference directly for the generation of high-energy phosphate. Since in these theories acyl phosphate is formed from inorganic phosphate, they are amenable to proof without isolation of particular intermediates, by means of radioactive phosphorus. It would be expected that the rate of conversion of inorganic phosphate to organic phosphate would be greater in light than in the dark. They have investigated this possibility under a variety of conditions and are unable to substantiate the theories.
Date: November 1, 1947
Creator: Aronoff, Sam & Calvin, Melvin
Partner: UNT Libraries Government Documents Department

Interfacial ionic and electronic conductivity in polymers. Progress report, June 1, 1988--December 31, 1988

Description: New phosphazen-based ([NP(OR){sub x}(OC{sub 2}H{sub 4}SO{sub 3}Na){sub 2-x}]{sub n}) single ion conductors were synthesized based on a polyphosphazene backbone and short-chain polyether sidechains, some of which are terminated with tetraalkylammonium groups. These materials are good anion conductors at room temperature. Related cation conductors were also prepared and characterized. Effects of interionic attractive interactions on the diffusion of a tracer were investigated theoretically. The results are relevant to ion pairing and trapping in polymer electrolytes.
Date: June 1, 1989
Creator: Shriver, D. F.
Partner: UNT Libraries Government Documents Department


Description: >Brief summaries are presented on isotopic dilution studies on salts dissolved in JCH/sub 3/OH, studies on metal and metal salts in solvents of the amine type, and studies on phosphato complexes of the pentammine Co(III) series. A list of papers published on reactions of solvated ions is included. (N.W.R.)
Date: September 24, 1962
Creator: Taube, H.
Partner: UNT Libraries Government Documents Department

New prodrugs based on phospholipid-nucleoside conjugates

Description: A method is described for the preparation of defined, isomerically pure phospholipid-nucleoside conjugates as a prodrug in which the drug (araC) is attached to the phospholipid by a monophosphate linkage. Key intermediates in the process involve selective blocking and deblocking of the nucleoside derivative. These particular monophosphate-linked derivatives represent a new class of prodrug, which are useful by themselves or in combination with diphosphate linked derivatives. Several new compositions involving diphosphate linked derivatives are described in which the products are isomerically pure and having defined fatty acid chain lengths.
Date: February 3, 1982
Creator: MacCoss, M.
Partner: UNT Libraries Government Documents Department

Chemical synthesis, characterization and separation studies of functionalized polymeric supports. Final report

Description: Polymer resins with immobilized phosphorus acid ligands have been used to remove metal ions from solutions over wide pH range. These resins offer selective removal of metal ions under acidic conditions through coordination with the phosphoryl oxygen. Use of poly(vinylbenzyl chloride) foams as supports for phosphorus-based ligands is examined in this report. Foams with large pore volumes as supports offer an advantage over gel and macroporous beads in that the increased porosity could lead to increased rates of metal ion complexation, and the larger pore size allows the use of more hydrophobic ligands such as phosphonate esters in metal ion complexations from aqueous solutions. Effects of crosslinking and sulfonation on metal ion complexation are also studied.
Date: October 27, 1994
Creator: Alexandratos, S.D. & Beauvais, R.
Partner: UNT Libraries Government Documents Department

TRI-2 Propyl Phosphate-Lanthanide Nitrate Complexes

Description: Tri-2-propyl phosphase (T2PP) reacts with lanthanide nitrates to form two series of solid complexes. These complexes were characterized by elemental analyses. X-ray diffraction patterns showed a single structure for each series, and infrared spectra showed that both nitrate and T2PP ligand were coordinated with lanthanide ions. The relative stabilities of the different species are discussed.
Date: August 29, 2001
Creator: McRae, J.R.
Partner: UNT Libraries Government Documents Department

Organophosphorus reagents in actinide separations: Unique tools for production, cleanup and disposal

Description: Interactions of actinide ions with phosphate and organophosphorus reagents have figured prominently in nuclear science and technology, particularly in the hydrometallurgical processing of irradiated nuclear fuel. Actinide interactions with phosphorus-containing species impact all aspects from the stability of naturally occurring actinides in phosphate mineral phases through the application of the bismuth phosphate and PUREX processes for large-scale production of transuranic elements to the development of analytical separation and environment restoration processes based on new organophosphorus reagents. In this report, an overview of the unique role of organophosphorus compounds in actinide production, disposal, and environment restoration is presented. The broad utility of these reagents and their unique chemical properties is emphasized.
Date: January 12, 2000
Creator: Nash, K. L.
Partner: UNT Libraries Government Documents Department

A novel synthesis of polyesters containing hexa-(tert-butylhydroquinone)cyclotriphosphazene

Description: The majority of polyphosphazene material research has concentrated on the linear polymer configuration. However, this represents only one of three potential backbone configurations for phosphazenes. Linear polymers are formed either directly from phosphorus and nitrogen containing precursors or from the ring opening polymerization of hexachlorocyclotriphosphazene. Two other backbone structures can be formed from hexachlorocyclotriphosphazene cyclolinear and cyclomatrix. Cyclolinear are the least studied due to synthetic difficulty. Cyclomatrix polymers represent a more facile method for forming non-linear phosphazenes.
Date: March 26, 2000
Creator: Stewart, F. F.; Luther, T. A.; Harrup, M. K. & Lash, R. P.
Partner: UNT Libraries Government Documents Department


Description: The pairing of a Lindqvist or Keggin polyoxometalate (POM) anion with an appropriate tetraalkylphosphonium cation, [R{sub 3}R{prime}P]{sup +}, has been shown to yield an original family of ionic liquids (POM-ILs), among them salts liquid at or near ambient temperature. The physicochemical properties of several such 'inorganic liquids', in particular their thermal properties, suggests the possible application of these compounds as robust, thermally-stable solvents for liquid-liquid extraction. A preliminary evaluation of the potential of POM-ILs in this application is presented.
Date: November 30, 2007
Partner: UNT Libraries Government Documents Department

The Path of Carbon in Photosynthesis. XX. The Steady State

Description: The separation of the phenomenon of photosynthesis in green plants into a photochemical reaction and into the light-dependent reduction of carbon dioxide is discussed, The reduction of carbon dioxide and the fate of the assimilated carbon were investigated with the help of the tracer technique (exposure of the planks to the radioactive C{sup 14}O{sub 2}) and of paper chromatography. A reaction cycle is proposed in which phosphoglyceric acid is the first isolable assimilations product. Analyses of the algal extracts which had assimilated radioactive carbon dioxide in a stationary condition ('steady-state' photosynthesis) for a long time provided further information concerning the proposed cycle and permitted the approximate estimation, for a number of compounds of what fraction of each compound was taking part in the cycle. The earlier supposition that light influences the respiration cycle was confirmed. The possibility of the assistance of {alpha}-lipoic acid, or of a related substance, in this influence and in the photosynthesis cycle, is discussed.
Date: September 1, 1952
Creator: Calvin, M. & Massini, Peter
Partner: UNT Libraries Government Documents Department

Flame Inhibition by Phosphorus-Containing Compounds over a Range of Equivalence Ratios

Description: There is much interest in the combustion mechanism of organophosphorus compounds (OPCs) due to their role as potential halon replacements in fire suppression. A continuing investigation of the inhibition activity of organophosphorus compounds under a range of equivalence ratios was performed experimentally and computationally, as measured by the burning velocity. Updates to a previous mechanism were made by the addition and modification of reactions in the mechanism for a more complete description of the recombination reactions. In this work, the laminar flame speed is measured experimentally and calculated numerically for a premixed propane/air flame, under a range of equivalence ratios, undoped and doped with dimethyl methylphosphonate (DMMP). A detailed investigation of the catalytic cycles involved in the recombination of key flame radicals is made for two equivalence ratios, lean and rich. From this, the importance of different catalytic cycles involved in the lean versus rich case is discussed. Although the importance of certain cycles is different under different stoichiometries, the OPCs are similarly effective across the range, demonstrating the robustness of OPCs as flame suppressants. In addition, it is shown that the phosphorus compounds are most active in the high temperature region of the flame. This may, in part, explain their high level of inhibition effectiveness.
Date: March 17, 2004
Creator: Jayaweera, T M; Melius, C F; Pitz, W J; Westbrook, C K; Korobeinichev, O P; Shvartsberg, V M et al.
Partner: UNT Libraries Government Documents Department