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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

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

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

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

NUCLEAR MAGNETIC RESONANCE SPECTRA OF TRIALKYL PHOSPHATES AND RELATED COMPOUNDS. I. PROTON MAGNETIC RESONANCE SPECTRA

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

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

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

SEPARATION OF TRITIATED WATER FROM WATER USING COMPOSITE MEMBRANES

Description: The work in this task involves the use of composite membranes to remove tritium from contaminated water at DOE sites. Experience with membrane systems in industry indicates that they are inherently energy efficient. Furthermore, membrane technologies such as reverse-osmosis have been well developed for desalination and other industrial/municipal applications. Aromatic polyphosphazenes were chosen as the polymeric material for the membranes being investigated because they have excellent radiological, thermal, and chemical stability. The FY-96 effort is directed toward empirical delineation of a potential mechanism, providing a statistical approach to data acquisition, further mass balance determination, and a preliminary design for the module staged array.
Date: December 18, 1995
Creator: JB, DUNCAN & DA, NELSON
Partner: UNT Libraries Government Documents Department

ORGANOPHOSPHORUS COMPOUNDS, OTHER THAN TBP, FOR PROCESSING OF IRRADIATED FUELS AND BY-PRODUCTS

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

Spectrophotometric Determination of Cerium With Tiron

Description: A spectrophotometric method for the determination of cerium and Tiron (disodium-1,2-dihydroxybenzene-3,5disulfonate) was applied to the determination of cerium in samples which contain uranium and zirconium. The ceriumTiron complex in solutions of pH 8 or greater exhibits an absorption maximum of 500 m mu . This reagent does not react with any other lanthanive element. The interference of iron, uranium, and zirconium was eliminated by extracting these interfering elements with a solution of trioctylphosphine oxide in cyclohexane. (auth)
Date: June 14, 1957
Creator: McDowell, B. L.; Meyer, A. S., Jr. & White, J. C.
Partner: UNT Libraries Government Documents Department

LDRD final report on polyphosphaacetylenes, new hybrid conducting organic-inorganic materials

Description: Thermal, electrochemical and transition metal mediated reactions of phosphaacetylene monomers were conducted in attempts to form novel polyphosphaacetylenes as a new class of potentially electrically conducting polymers. Molecular modeling was used to simulate the molecular conformations of optimized, isolated oligomers to identify the proper monomeric repeat units for highly conjugated molecules. Electrodeposition of suitable monomers led to low molecular weight oligomers. Thermal polymerization of phosphaacetylene monomers bearing aromatic substituents ed to the formation of polyhedral cage oligomers. Under metathesis polymerization conditions the phosphaacetylene monomers form unique complexes via an unprecedented sequence of intermediates which suggest that metathesis to linear oligomers is achievable. Conductivity measurements on electrodeposited oligomers indicate modest electrical conductivity.
Date: June 1, 1996
Creator: Jamison, G.M.; Loy, D.A.; Saunders, R.S. & Alam, T.M.
Partner: UNT Libraries Government Documents Department

Evaporation of Enriched Uranium Solutions Containing Organophosphates

Description: The Savannah River Site has enriched uranium (EU) solution which has been stored for almost 10 years since being purified in the second uranium cycle of the H area solvent extraction process. The preliminary SRTC data, in conjunction with information in the literature, is promising. However, very few experiments have been run, and none of the results have been confirmed with repeat tests. As a result, it is believed that insufficient data exists at this time to warrant Separations making any process or program changes based on the information contained in this report. When this data is confirmed in future testing, recommendations will be presented.
Date: March 18, 1999
Creator: Pierce, R.A.
Partner: UNT Libraries Government Documents Department

Synthesis and characterization of polyphosphazene copolymers using phosphorus-31 NMR spectroscopy

Description: It was observed that competitive nucleophilic addition processes may be observed by {sup 31}P NMR spectroscopy. Methoxyethoxyethanol (MEE) and p-methoxyphenol readily substitute for chlorineonto phosphorus and the relative rates are generally comparable to each other. Sterically, the phenol presents is slightly larger than MEE but this does not appear to effect substitution judging by the observed PN(OAr){sub 2} NMR signal. These processes are still being studied.
Date: January 1, 1997
Creator: Stewart, F.F.; Peterson, E.S.; Stone, M.L. & Singler, R.E.
Partner: UNT Libraries Government Documents Department

Results of RCRA groundwater quality assessment at the 216-B-3 Pond Facility

Description: This document describes a groundwater quality assessment of the 216-B-3 pond system, a Resources Conservation and Recovery act of 1976 (RCRA) waste facility. In 1990, sampling and chemical analysis of groundwater underlying the facility indicated that the contamination indicator parameters, total organic halogens (TOX), and total organic carbon (TOC) had exceeded established limits in two wells. This discovery placed the facility into RCRA groundwater assessment status and subsequently led to a more detailed hydrochemical analysis of groundwater underlying the facility. Comprehensive chemical analyses of groundwater samples from 1994 through 1996 revealed one compound, tris (2-chloroethyl) phosphate (TRIS2CH), that may have contributed to elevated TOX concentrations. No compound was identified as a contributor to TOC. Detailed evaluations of TOX, TOC, and TRIS2CH and comparison of occurrences of these parameters led to conclusions that (1) with few exceptions, these constituents occur at low concentrations below or near limits of quantitation; (2) it is problematic whether the low concentrations of TRIS2CH represent a contaminant originating from the facility or if it is a product of well construction; and (3) given the low and diminishing concentration of TOX, TOC, and TRIS2CH, no further investigation into the occurrent of these constituents is justified. Continued groundwater monitoring should include an immediate recalculation of background critical means of upgradient/downgradient comparisons and a return to seminannual groundwater monitoring under a RCRA indicator parameter evaluation program.
Date: June 1, 1997
Creator: Barnett, D.B. & Teel, S.S.
Partner: UNT Libraries Government Documents Department

Develop safe, low-cost method of manufacturing rechargeable, high conductivity lithium batteries. Final report

Description: The focus of much of this work is the rechargeable lithium battery, because of its high energy density, and the use of solid polymer electrolytes (SPE`s) for ease of fabrication and lightness of weight. The classical solid polymer electrolyte is based on the use of salts such as lithium triflate dissolved in poly(ethylene oxide) (PEO) or poly(propylene oxide). This specific polymer electrolyte has severe limitations. Poly(ethylene oxide) is a microcrystalline polymer at 25 C, and ion migration occurs only in the 20--30% of the material that is amorphous. Useable conductivities (10{sup {minus}5} S/cm) can be achieved only when the material is heated above 80 C. Two approaches to generate higher electrolyte conductivities at ambient temperatures are being developed. In the first, organic solvents are added to the polymer to plasticize it and dissolve the microcrystallites. This increases the conductivity but raises the possibility of fires if the battery casing ruptures during high charge or discharge conditions or when the device is punctured by impact. The alternative is to design new polymers that are good solid electrolyte media but which are completely amorphous and have low glass transition temperatures. Such a polymer is MEEP (poly[bis(methoxyethoxy)phosphazene]), first synthesized in the author`s laboratories. The main objective was to develop crosslinking methods for MEEP which could be used on a mass production scale to produce thin film rechargeable lithium batteries. A further objective was to assemble working energy storage devices to investigate the feasibility that this system could be developed commercially.
Date: December 1, 1997
Creator: Allcock, H. R.
Partner: UNT Libraries Government Documents Department