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Dependence of secondary ion emission from organic material on the energy loss of the impacting heavy ion

Description: Samples of the amino acid valine were irradiated by 2.5 MeV-Ar, 0.8 MeV-Kr and 1.0 MeV Xe beams from the Argonne Dynamitron accelerator in order to study the energy distributions of ejected secondary ions. For Kr and Xe the nuclear stopping power exceeded the electronic stopping power by a factor 2 or 3, respectively, but the functional shape of the energy distributions and the mean ejection energies (0.9--1.4 eV) indicated that the molecular ions (M{plus minus}H){sup {plus minus}} are desorbed… more
Date: January 1, 1991
Creator: Hunt, J.E. (Argonne National Lab., IL (United States)) & Wien, K. (Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Anaerobic fermentation of simulated in-situ oil shale retort water

Description: The feasibility of removing soluble organics from oil shale retort water by anaerobic digestion with methane production was experimentally investigated. The following conclusions were made. The retort water studied had to be pretreated to remove toxic and add deficient constituents before it could be successfully treated with the anaerobic fermentation process. Pretreatment included pH adjustment to 7, ammonia reduction, and nutrient addition. A digested sludge from a conventional municipal sew… more
Date: November 1, 1977
Creator: Ossio, E. A.; Fox, J. P.; Thomas, J. F. & Poulson, R. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Short-lived positron emitter labeled radiotracers - present status

Description: The preparation of labelled compounds is important for the application of positron emission transaxial tomography (PETT) in biomedical sciences. This paper describes problems and progress in the synthesis of short-lived positron emitter (/sup 11/C, /sup 18/F, /sup 13/N) labelled tracers for PETT. Synthesis of labelled sugars, amino acids, and neurotransmitter receptors (pimozide and spiroperidol tagged with /sup 11/C) is discussed in particular. (DLC)
Date: January 1, 1982
Creator: Fowler, J. S. & Wolf, A. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mineralogy in the Waste Isolation Pilot Plant (WIPP) facility stratigraphic horizon

Description: Forty-six samples were selected for this study from two cores, one extending 50 ft up through the roof of the WIPP facility and the other penetrating 50 ft below the facility floor. These samples, selected from approximately every other foot of core length, represent the major lithologies present in the immediate vicinity of the WIPP facility horizon: ''clean'' halite, polyhalitic halite, argillaceous halite, and mixed polyhalitic-argillaceous halite. Samples were analyzed for non-NaCl mineralo… more
Date: September 1, 1985
Creator: Stein, C. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Steroselective synthesis and application of L-( sup 15 N) amino acids

Description: We have developed two general approaches to the stereoselective synthesis of {sup 15}N- and {sup 13}C-labeled amino acids. First, labeled serine, biosynthesized using the methylotrophic bacterium M. extorquens AM1, serves as a chiral precursor for the synthesis of other amino acids. For example, pyridoxal phosphate enzymes can be used for the conversion of L-({alpha}-{sup 15}N)serine to L-({alpha}-{sup 15}N)tyrosine, L-({alpha}-{sup 15}N)tryptophan, and L-({alpha}-{sup 15}N)cysteine. In the sec… more
Date: January 1, 1991
Creator: Unkefer, C.J. (Los Alamos National Lab., NM (United States)) & Lodwig, S.N. (Centralia Coll., WA (United States). Div. of Science)
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Partner: UNT Libraries Government Documents Department
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Radiation effects and metalloproteins studied by x-ray photoelectron spectroscopy

Description: X-ray photoelectron spectroscopy (XPS) is used to study the bonding structure at the iron site of cytochrome c and the bonding of rare earth ions to the phosphate oxygens of ATP. Radiation effects are studied on several amino acid and simple peptide model systems. The emission spectrum of the x-ray source is calculated from literature references. The distributions of photon energy as a function of photon frequency and as a function of take-off angle are obtained. From these distributions, the r… more
Date: July 1, 1975
Creator: Wurzbach, J.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, March 1, 1977--May 31, 1977

Description: The degradation of cellulosic biomass continues to focus on the anaerobic thermophile Clostridium thermocellum. When grown on crystalline cellulose (MN300) in batch culture, there is an initial rapid accumulation of reducing sugars but the sugars are rapidly metabolized in later times during the fermentation. When grown on Solka floc with periodic addition of the substrate, there is a continual accumulation of reducing sugars (xylose, glucose, and cellobiose) as well as ethanol and acetic acid … more
Date: June 1, 1977
Creator: Wang, D. I. C.; Cooney, C. L.; Demain, A. L.; Gomez, R. F. & Sinskey, A. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The magnesium chelation step in chlorophyll biosynthesis

Description: The biogenesis of energy transducing membranes requires the coordinate synthesis of prosthetic groups, proteins and lipids. Two of the major prosthetic groups, chlorophyll and heme, share a common biosynthetic pathway that diverges at the point of metal insertion into protoporphyrin IX. Insertion of iron leads to heme, while insertion of magnesium leads to chlorophyll. The Mg-chelatase from intact cucumber chloroplasts has been characterized with regard to substrate specificity, regulation, ATP… more
Date: January 1, 1991
Creator: Weinstein, J.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On-line analysis of chemical composition using an FT-Raman spectrometer in the near-ir

Description: Newly commercialized Fourier transform Raman spectroscopic instrumentation provides a simpler alternative for vibrational spectroscopic analysis. Instrument vendors currently design for laboratory use, but there are many potential process applications of these stable, easy to use instruments. Raman spectroscopy is highly suited to analysis of aqueous samples. Near infrared excitation minimized fluorescence interference and allows for remote operation via fiber optic probes. The Department of En… more
Date: January 1, 1992
Creator: Garrison, A.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Volatilities of ruthenium, iodine, and technetium on calcining fission product nitrate wastes

Description: Various high-level nitrate wastes were subjected to formic acid denitration. Formic acid reacts with the nitrate anion to yield noncondensable, inert gases according to the following equation: 4 HCOOH + 2 HNO/sub 3/ ..-->.. N/sub 2/O + 4 CO/sub 2/ + 5 H/sub 2/O. These gases can be scrubbed free of /sup 106/Ru, /sup 131/I, and /sup 99/Tc radioactivities prior to elimination from the plant by passage through HEPA filters. The formation of deleterious NO/sub x/ is avoided. Moreover, formic acid re… more
Date: January 1, 1980
Creator: Rimshaw, S. J. & Case, F. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of Prudhoe Bay crude oil in sediment on Abarenicola pacifica in laboratory and field experiments

Description: Behavioral responses of organisms are often sensitive indicators of changes in the environment over short time frames. The rate of burrowing of Abarenicola pacifica, a lugworm typical of muddy tidal flats, was studied to determine its response to the presence of hydrocarbons in the environment. If a reduction in burrowing rates is reflected in reduced food intake, a decline in nutritional status might be expected. The level of free amino acids in the tissues was examined as a possible indicator… more
Date: February 1, 1980
Creator: Augenfeld, J.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gene-enzyme telationships in somatic cells and their organismal derivatives in higher plants. Progress report

Description: Progress is reported in the following subject areas: (1) chemistry of the arogenate molecule; (2) plant enzymology at the organismal level; (3) isolation of regulatory mutants in tobacco; and (4) stability of the haploid state in Nicotiana sylvestris.
Date: April 21, 1980
Creator: Jensen, R. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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New chromatographic materials for the separation and concentration of uranium from environmental matrices

Description: Extraction chromatography, in which an inert support is impregnated with an extractant solution to form a chromatographic resin, combines the specificity of extraction with the ease of operation of an ion exchange column, thereby overcoming the principal drawbacks of the two methods when used alone. Previous work in this laboratory on the design of selective extractants for use in nuclear fuel reprocessing and in nuclear waste treatment has led to the development of several new phosphorus-based… more
Date: January 1, 1991
Creator: Horwitz, E.P.; Dietz, M.L.; Chiarizia, R. & Diamond, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation on the occurrence and significance of cyclic adenosine 3':5'-monophosphate in phytoplankton and natural aquatic communities

Description: This study is an investigation into the occurrence and potential functions of cyclic adenosine 3':5'-monophosphate (cAMP), a potent and ubiquitous metabolic regulatory molecule in heterotrophic organisms, in phytoplankton and in natural aquatic communities. Laboratory-cultured phytoplankton were grown under both optimal and suboptimal nutrient regimes under constant temperature and illumination regimes. Cellular and extracellular cAMP production, characterized by a number of biochemical techniq… more
Date: January 1, 1980
Creator: Francko, D.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of the mechanism of carcinogenesis by carcinogens which are negative in the Ames test. Progress report. [ICE; TUMOR PROMOTERS; PROGESTERONE; QUANTITY RATIO; RATS]

Description: Research progress for 1980 is reported. The role of tRNA methyltransferases in two-1 stage carcinogenesis of mice by phorbol esters has been investigated. The mechanisms of elevation of progesterone levels in the rat by ethionine have also beed studied. (ACR)
Date: unknown
Creator: Borek, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Interdisciplinary research and training program in the plant sciences

Description: This document is the compiled progress reports from the Interdisciplinary Research and Training Program in the Plant Sciences funded through the MSU-DOE Plant Research Laboratory. Fourteen reports are included, covering topics such as the molecular basis of plant/microbe symbiosis, cell wall proteins and assembly, gene expression, stress responses, growth regulator biosynthesis, interaction between nuclear and organelle genomes, sensory transduction and tropisms, intracellular sorting and membr… more
Date: January 1, 1991
Creator: Wolk, C.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spectrophotometric determination of uranium(IV) with Arsenazo III

Description: A spectrophotometric procedure was developed for determining U(IV) in the presence of U(VI) by forming a colored complex with Arsenazo III in 4M HCl. The results compare satisfactorily with U(IV) determinations by ceric titration. Total uranium can be determined after reduction of U(VI) with metallic zinc. The concentration range for the absorbance cell solution is 0 to 2 ..mu..g U(IV)/mL. Other tetravalent ions, such as thorium, zirconium, hafnium, plutonium, and neptunium, will interfere.
Date: July 1, 1980
Creator: Baumann, E. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radionuclide distributions and migration mechanisms at shallow land burial sites. Annual report of research investigations on the distribution, migration and containment of radionuclides at Maxey Flats, Kentucky. [Maxey Flats]

Description: Subsurface waters at Maxey Flats are anoxic systems with high alkalinity and high concentrations of dissolved ferrous ion. Americium and cobalt in these trench waters are made more soluble by the presence of EDTA, while strontium and cesium are unaffected under the same conditions. EDTA is the major organic complexing component in waste trench 27 leachate, but other polar, water-soluble organics are also present. Evidence points to the migration of plutonium between waste trench 27 and inert at… more
Date: July 1, 1982
Creator: Kirby, L. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vectorially photoinduced electron-transfer processes across water-in-oil interfaces of microemulsions

Description: Artificial photosynthetic devices are potential fuel sources. The basic idea in the design of such devices is a photosensitized electron-transfer that yields chemical species capable of reducing and oxidizing water to hydrogen and oxygen. A fundamental difficulty in effecting this transfer is the thermodynamically favored back reactions of the intermediary redox species. An interfacial model composed of a water-in-oil microemulsion is suggested to provide the separation of these redox species, … more
Date: July 1, 1980
Creator: Willner, I.; Otvos, J. W. & Calvin, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evaluation of Wastewater Treatment Requirements for Thermochemical Biomass Liquefaction

Description: Biomass can provide a substantial energy source. Liquids are preferred for use as transportation fuels because of their high energy density and handling ease and safety. Liquid fuel production from biomass can be accomplished by any of several different processes including hydrolysis and fermentation of the carbohydrates to alcohol fuels, thermal gasification and synthesis of alcohol or hydrocarbon fuels, direct extraction of biologically produced hydrocarbons such as seed oils or algae lipids,… more
Date: April 1, 1992
Creator: Elliott, D. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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