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Sample records for real uranium plant

  1. Solubility characterization of airborne uranium from a uranium recycling plant.

    PubMed

    Metzger, Robert; Cole, Leslie

    2004-07-01

    Solubility profiles of uranium dusts in a uranium recycling plant were determined by performing in vitro solubility tests on breathing zone air samples conducted in all process areas of the processing plant. The recycling plant produces high density shields, closed end tubes that are punched and formed from uranium sheet metal, and high-fired uranium oxide, which is used as a catalyst. The recycled uranium is cut and melted in a vacuum furnace, and part of the molten uranium is poured into molds for further processing. Air samples were taken in process areas under normal working conditions. The dissolution rate of the uranium in a simulant solution of extracellular airway lining fluid (Gamble's solution) was then determined over the next 28 d. Airborne uranium in the oxide section of the plant was found to be highly insoluble with 99% of the uranium having a dissolution half time in excess of 100 d. The solubility of the airborne uranium in other areas of the facility was only slightly more soluble with over 90% of the airborne uranium having dissolution half times in excess of 90 d.

  2. Uranium uptake by hydroponically cultivated crop plants.

    PubMed

    Soudek, Petr; Petrová, Sárka; Benešová, Dagmar; Dvořáková, Marcela; Vaněk, Tomáš

    2011-06-01

    Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC(50) value about 0.1mM. Cucumis sativa represented the most resistant plant to uranium (EC(50)=0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1mM. Twenty different plant species were tested in hydroponic solution supplemented by 0.1mM or 0.5mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Plant-uptake of uranium: Hydroponic and soil system studies

    USGS Publications Warehouse

    Ramaswami, A.; Carr, P.; Burkhardt, M.

    2001-01-01

    Limited information is available on screening and selection of terrestrial plants for uptake and translocation of uranium from soil. This article evaluates the removal of uranium from water and soil by selected plants, comparing plant performance in hydroponic systems with that in two soil systems (a sandy-loam soil and an organic-rich soil). Plants selected for this study were Sunflower (Helianthus giganteus), Spring Vetch (Vicia sativa), Hairy Vetch (Vicia villosa), Juniper (Juniperus monosperma), Indian Mustard (Brassica juncea), and Bush Bean (Phaseolus nanus). Plant performance was evaluated both in terms of the percent uranium extracted from the three systems, as well as the biological absorption coefficient (BAC) that normalized uranium uptake to plant biomass. Study results indicate that uranium extraction efficiency decreased sharply across hydroponic, sandy and organic soil systems, indicating that soil organic matter sequestered uranium, rendering it largely unavailable for plant uptake. These results indicate that site-specific soils must be used to screen plants for uranium extraction capability; plant behavior in hydroponic systems does not correlate well with that in soil systems. One plant species, Juniper, exhibited consistent uranium extraction efficiencies and BACs in both sandy and organic soils, suggesting unique uranium extraction capabilities.

  4. Uranium mill tailings remedial action project real estate management plan

    SciTech Connect

    Not Available

    1994-09-01

    This plan summarizes the real estate requirements of the US Department of Energy`s (DOE) Uranium Mill Tailings Action (UMTRA) Project, identifies the roles and responsibilities of project participants involved in real estate activities, and describes the approaches used for completing these requirements. This document is intended to serve as a practical guide for all project participants. It is intended to be consistent with all formal agreements, but if a conflict is identified, the formal agreements will take precedence.

  5. The uranium cylinder assay system for enrichment plant safeguards

    SciTech Connect

    Miller, Karen A; Swinhoe, Martyn T; Marlow, Johnna B; Menlove, Howard O; Rael, Carlos D; Iwamoto, Tomonori; Tamura, Takayuki; Aiuchi, Syun

    2010-01-01

    Safeguarding sensitive fuel cycle technology such as uranium enrichment is a critical component in preventing the spread of nuclear weapons. A useful tool for the nuclear materials accountancy of such a plant would be an instrument that measured the uranium content of UF{sub 6} cylinders. The Uranium Cylinder Assay System (UCAS) was designed for Japan Nuclear Fuel Limited (JNFL) for use in the Rokkasho Enrichment Plant in Japan for this purpose. It uses total neutron counting to determine uranium mass in UF{sub 6} cylinders given a known enrichment. This paper describes the design of UCAS, which includes features to allow for unattended operation. It can be used on 30B and 48Y cylinders to measure depleted, natural, and enriched uranium. It can also be used to assess the amount of uranium in decommissioned equipment and waste containers. Experimental measurements have been carried out in the laboratory and these are in good agreement with the Monte Carlo modeling results.

  6. Laser fluorometric analysis of plants for uranium exploration

    USGS Publications Warehouse

    Harms, T.F.; Ward, F.N.; Erdman, J.A.

    1981-01-01

    A preliminary test of biogeochemical exploration for locating uranium occurrences in the Marfa Basin, Texas, was conducted in 1978. Only 6 of 74 plant samples (mostly catclaw mimosa, Mimosa biuncifera) contained uranium in amounts above the detection limit (0.4 ppm in the ash) of the conventional fluorometric method. The samples were then analyzed using a Scintrex UA-3 uranium analyzer* * Use of trade names in this paper is for descriptive purposes only and does not constitute endorsement by the U.S. Geological Survey. - an instrument designed for direct analysis of uranium in water, and which can be conveniently used in a mobile field laboratory. The detection limit for uranium in plant ash (0.05 ppm) by this method is almost an order of magnitude lower than with the fluorometric conventional method. Only 1 of the 74 samples contained uranium below the detection limit of the new method. Accuracy and precision were determined to be satisfactory. Samples of plants growing on mineralized soils and nonmineralized soils show a 15-fold difference in uranium content; whereas the soils themselves (analyzed by delayed neutron activation analysis) show only a 4-fold difference. The method involves acid digestion of ashed tissue, extraction of uranium into ethyl acetate, destruction of the ethyl acetate, dissolution of the residue in 0.005% nitric acid, and measurement. ?? 1981.

  7. Uptake of uranium by aquatic plants growing in fresh water ecosystem around uranium mill tailings pond at Jaduguda, India.

    PubMed

    Jha, V N; Tripathi, R M; Sethy, N K; Sahoo, S K

    2016-01-01

    Concentration of uranium was determined in aquatic plants and substrate (sediment or water) of fresh water ecosystem on and around uranium mill tailings pond at Jaduguda, India. Aquatic plant/substrate concentration ratios (CRs) of uranium were estimated for different sites on and around the uranium mill tailings disposal area. These sites include upstream and downstream side of surface water sources carrying the treated tailings effluent, a small pond inside tailings disposal area and residual water of this area. Three types of plant groups were investigated namely algae (filamentous and non-filamentous), other free floating & water submerged and sediment rooted plants. Wide variability in concentration ratio was observed for different groups of plants studied. The filamentous algae uranium concentration was significantly correlated with that of water (r=0.86, p<0.003). For sediment rooted plants significant correlation was found between uranium concentration in plant and the substrate (r=0.88, p<0.001). Both for other free floating species and sediment rooted plants, uranium concentration was significantly correlated with Mn, Fe, and Ni concentration of plants (p<0.01). Filamentous algae, Jussiaea and Pistia owing to their high bioproductivity, biomass, uranium accumulation and concentration ratio can be useful for prospecting phytoremediation of stream carrying treated or untreated uranium mill tailings effluent. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Environmental consequences of uranium atmospheric releases from fuel cycle facility: II. The atmospheric deposition of uranium and thorium on plants.

    PubMed

    Pourcelot, L; Masson, O; Renaud, P; Cagnat, X; Boulet, B; Cariou, N; De Vismes-Ott, A

    2015-03-01

    Uranium and thorium isotopes were measured in cypress leaves, wheat grains and lettuce taken in the surroundings of the uranium conversion facility of Malvési (South of France). The comparison of activity levels and activity ratios (namely (238)U/(232)Th and (230)Th/(232)Th) in plants with those in aerosols taken at this site and plants taken far from it shows that aerosols emitted by the nuclear site (uranium releases in the atmosphere by stacks and (230)Th-rich particles emitted from artificial ponds collecting radioactive waste mud) accounts for the high activities recorded in the plant samples close to the site. The atmospheric deposition process onto the plants appears to be the dominant process in plant contamination. Dry deposition velocities of airborne uranium and thorium were measured as 4.6 × 10(-3) and 5.0 × 10(-3) m s(-1), respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. U-Pb geochronology of the Lagoa Real uranium district, Brazil: Implications for the age of the uranium mineralization

    NASA Astrophysics Data System (ADS)

    Lobato, Lydia Maria; Pimentel, Márcio Martins; Cruz, Simone C. P.; Machado, Nuno; Noce, Carlos Maurício; Alkmim, Fernando Flecha

    2015-03-01

    The Lagoa Real uranium district in Bahia, northeastern Brazil, is the most important uranium province in the country and presently produces this metal in an open-pit mine operated by Indústrias Nucleares do Brasil. Uranium-rich zones are associated with plagioclase (dominantly albite ± oligoclase) -rich rocks, albitites and metasomatized granitic-gneisses, distributed along NNW/SSE striking shear zones. We have used the ID-TIMS U-Pb method to date zircon and titanite grains from the São Timóteo granitoid, and albite-rich rocks from the Lagoa Real district in order to assess the age of granite emplacement, deformation/metamorphism and uranium mineralization. The isotopic data support the following sequence of events (i) 1746 ± 5 Ma - emplacement of the São Timóteo granitoid (U-Pb zircon age) in an extensional setting, coeval with the beginning of the sedimentation of the Espinhaço Supergroup; (ii) 956 ± 59 Ma hydrothermal alteration of the São Timóteo granitoid and emplacement of the uranium mineralization (U-Pb titanite age on an albite-rich sample); (iii) 480 Ma metamorphism, remobilization and Pb loss (U-Pb titanite age for the gneiss sample), during the nucleation of shear zones related to the collision between the São Francisco-Congo and Amazonia paleoplates. The 956 ± 59-Ma mineralization age is apparently associated with the evolution of the Macaúbas-Santo Onofre rift. This age bracket may bear an important exploration implication, and should be included in the diverse age scenario of uranium deposits worldwide.

  10. Uptake of uranium and thorium by native and cultivated plants.

    PubMed

    Shtangeeva, I

    2010-06-01

    Large part of available literature on biogeochemistry of uranium and thorium refers to the studies performed either in highly contaminated areas or in nutrient solutions that have been artificially 'spiked' with radionuclides. Effects of background levels of natural radioactivity on soil-grown plants have not been studied to the same extent. In this paper, we summarised results of greenhouse and field experiments performed by the author from 2000 to 2006. We examined some of the factors affecting transfer of U and Th from soil to plants, differences in uptake of these radionuclides by different plants, relationships between U and Th in soil and in plants, and temporal variations of U and Th in different plant species. Concentrations of radionuclides (critical point for experimental studies on biogeochemistry of U and Th--rare trace elements in non-contaminated regions) and essential plant nutrients and trace elements were determined by instrumental neutron activation analysis. Copyright (c) 2008 Elsevier Ltd. All rights reserved.

  11. Uranium accumulation by aquatic plants from uranium-contaminated water in Central Portugal.

    PubMed

    Pratas, João; Favas, Paulo J C; Paulo, Carlos; Rodrigues, Nelson; Prasad, M N V

    2012-03-01

    Several species of plants have developed a tolerance to metal that enables them to survive in metal contaminated and polluted sites. Some of these aquatic plants have been reported to accumulate significant amounts of specific trace elements and are, therefore, useful for phytofiltration. This work focuses the potential of aquatic plants for the phytofiltration of uranium (U) from contaminated water. We observed that Callitriche stagnalis, Lemna minor, and Fontinalis antipyretica, which grow in the uraniferous geochemical province of Central Portugal, have been able to accumulate significant amounts of U. The highest concentration of U was found in Callitriche stagnalis (1948.41 mg/kg DW), Fontinalis antipyretica (234.79 mg/kg DW), and Lemna minor (52.98 mg/kg DW). These results indicate their potential for the phytofiltration of U through constructed treatment wetlands or by introducing these plants into natural water bodies in the uraniferous province of Central Portugal.

  12. Pilot plant operation of the Uranium Chip Oxidation Facility at the Y-12 Plant

    SciTech Connect

    Childs, Y.C.

    1987-01-16

    Due to changing environmental regulations, the current practice of depleted uranium chip (machine turning) disposal via shallow land burial has become environmentally objectionable. The chips are pyrophoric and oxidize rapidly when exposed to air; therefore, long-term storage of the uranium chips presents a major fire hazard. The Oak Ridge Y-12 Plant Development Division was contacted to devise a disposal method that would eliminate chip burial and minimize storage space requirements. The proposed method of accomplishing this task was oxidizing the uranium chips to uranium oxide (U/sub 3/O/sub 8/) under controlled conditions. Pilot plant operation of the Uranium Chip Oxidation Facility (UCOF) was initiated on May 20, 1985, by the Y-12 Development Division. The purpose of this initial development testing was to evaluate the equipment, determine operating parameters, and provide on-the-job training for Waste Treatment Operations (WTO) personnel. Startup of the UCOF began with the check-out of the equipment using only the No. 1 oxidizer. Following the verification stage, the oxidizer was loaded with an initial charge of cold uranium oxide (U/sub 3/O/sub 8/) in preparation for test burning. Results of the test are given.

  13. Uranium fate in wetland mesocosms: Effects of plants at two ...

    EPA Pesticide Factsheets

    Small-scale continuous flow wetland mesocosms (~0.8 L) were used to evaluate how plant roots under different iron loadings affect uranium (U) mobility. When significant concentrations of ferrous iron (Fe) were present at circumneutral pH values, U concentrations in root exposed sediments were an order of magnitude greater than concentrations in root excluded sediments. Micro X-ray absorption near-edge structure (µ-XANES) spectroscopy indicated that U was associated with the plant roots primarily as U(VI) or U(V), with limited evidence of U(IV). Micro X-ray fluorescence (µ-XRF) of plant roots suggested that for high iron loading at circumneutral pH, U was co-located with Fe, perhaps co-precipitated with root Fe plaques, while for low iron loading at a pH of ~4 the correlation between U and Fe was not significant, consistent with previous observations of U associated with organic matter. Quantitative PCR analyses indicated that the root exposed sediments also contained elevated numbers of Geobacter spp., which are likely associated with enhanced iron cycling, but may also reduce mobile U(VI) to less mobile U(IV) species. There are significant uncertainties regarding the environmental fate of uranium (U) and efforts to minimize U exposures require understanding of its mobility in environmental systems. Much research has focused on sequestering U as solids within groundwater aquifers, where localized risks can be controlled.1 Subsurface sequestration limits t

  14. Uranium fate in wetland mesocosms: Effects of plants at two ...

    EPA Pesticide Factsheets

    Small-scale continuous flow wetland mesocosms (~0.8 L) were used to evaluate how plant roots under different iron loadings affect uranium (U) mobility. When significant concentrations of ferrous iron (Fe) were present at circumneutral pH values, U concentrations in root exposed sediments were an order of magnitude greater than concentrations in root excluded sediments. Micro X-ray absorption near-edge structure (µ-XANES) spectroscopy indicated that U was associated with the plant roots primarily as U(VI) or U(V), with limited evidence of U(IV). Micro X-ray fluorescence (µ-XRF) of plant roots suggested that for high iron loading at circumneutral pH, U was co-located with Fe, perhaps co-precipitated with root Fe plaques, while for low iron loading at a pH of ~4 the correlation between U and Fe was not significant, consistent with previous observations of U associated with organic matter. Quantitative PCR analyses indicated that the root exposed sediments also contained elevated numbers of Geobacter spp., which are likely associated with enhanced iron cycling, but may also reduce mobile U(VI) to less mobile U(IV) species. There are significant uncertainties regarding the environmental fate of uranium (U) and efforts to minimize U exposures require understanding of its mobility in environmental systems. Much research has focused on sequestering U as solids within groundwater aquifers, where localized risks can be controlled.1 Subsurface sequestration limits t

  15. Phytoremediation of uranium-contaminated soils: Role of organic acids in triggering uranium hyperaccumulation in plants

    SciTech Connect

    Huang, J.W.; Blaylock, M.J.; Kapulnik, Y.; Ensley, B.D.

    1998-07-01

    Uranium phytoextraction, the use of plants to extract U from contaminated soils, is an emerging technology. The authors report on the development of this technology for the cleanup of U-contaminated soils. In this research, they investigated the effects of various soil amendments on U desorption from soil to soil solution, studied the physiological characteristics of U uptake and accumulation in plants, and developed techniques to trigger U hyperaccumulation in plants. A key to the success of U phytoextraction is to increase soil U availability to plants. The authors have found that some organic acids can be added to soils to increase U desorption from soil to soil solution and to trigger a rapid U accumulation in plants. Of the organic acids (acetic acid, citric acid, and malic acid) tested, citric acid was the most effective in enhancing U accumulation in plants. Shoot U concentrations of Brassica juncea and Brassica chinensis grown in a U-contaminated soil increased from less than 5 mg kg{sup {minus}1} to more than 5,000 mg kg{sup {minus}1} in citric acid-treated soils. To their knowledge, this is the highest shoot U concentration reported for plants grown on U-contaminated soils. Using this U hyperaccumulation technique, they are now able to increase U accumulation in shoots of selected plant species grown in two U-contaminated soils by more than 1,000-fold within a few days. The results suggest that U phytoextraction may provide an environmentally friendly alternative for the cleanup of U-contaminated soils.

  16. CRITICALITY CONTROL DURING THE DISMANTLING OF A URANIUM CONVERSION PLANT

    SciTech Connect

    LADURELLE, Laurent; LISBONNE, Pierre

    2003-02-27

    Within the Commissariat a l'Energie Atomique, in the Cadarache Research Center in southern France, the production at the Enriched Uranium Treatment Workshops started in 1965 and ended in 1995. The dismantling is in progress and will last until 2006. The decommissioning is planned in 2007. Since the authorized enrichment in 235U was 10% in some parts of the plant, and unlimited in others, the equipment and procedures were designed for criticality control during the operating period. Despite the best previous removing of the uranium in the inner parts of the equipment, evaluation of the mass of remaining fissile material by in site gamma spectrometry measurement shows that the safety of the ''clean up'' operations requires specific criticality control procedures, this mass being higher than the safe mass. The chosen method is therefore based on the mapping of fissile material in the contaminated parts of the equipment and on the respect of particular rules set for meeting the criticality control standards through mass control. The process equipment is partitioned in separated campaign, and for each campaign the equipment dismantling is conducted with a precise traceability of the pieces, from the equipment to the drum of waste, and the best final evaluation of the mass of fissile material in the drum. The first results show that the mass of uranium found in the dismantled equipment is less than the previous evaluation, and they enable us to confirm that the criticality was safely controlled during the operations. The mass of fissile material remaining in the equipment can be then carefully calculated, when it is lower than the minimal critical mass, and on the basis of a safety analysis, we will be free of any constraints regarding criticality control, this allowing to make procedures easier, and to speed up the operations.

  17. Idaho Chemical Processing Plant and Plutonium-Uranium Extraction Plant phaseout/deactivation study

    SciTech Connect

    Patterson, M.W.; Thompson, R.J.

    1994-01-01

    The decision to cease all US Department of Energy (DOE) reprocessing of nuclear fuels was made on April 28, 1992. This study provides insight into and a comparison of the management, technical, compliance, and safety strategies for deactivating the Idaho Chemical Processing Plant (ICPP) at Westinghouse Idaho Nuclear Company (WINCO) and the Westinghouse Hanford Company (WHC) Plutonium-Uranium Extraction (PUREX) Plant. The purpose of this study is to ensure that lessons-learned and future plans are coordinated between the two facilities.

  18. Uranium*

    NASA Astrophysics Data System (ADS)

    Grenthe, Ingmar; Drożdżyński, Janusz; Fujino, Takeo; Buck, Edgar C.; Albrecht-Schmitt, Thomas E.; Wolf, Stephen F.

    Uranium compounds have been used as colorants since Roman times (Caley, 1948). Uranium was discovered as a chemical element in a pitchblende specimen by Martin Heinrich Klaproth, who published the results of his work in 1789. Pitchblende is an impure uranium oxide, consisting partly of the most reduced oxide uraninite (UO2) and partly of U3O8. Earlier mineralogists had considered this mineral to be a complex oxide of iron and tungsten or of iron and zinc, but Klaproth showed by dissolving it partially in strong acid that the solutions yielded precipitates that were different from those of known elements. Therefore he concluded that it contained a new element (Mellor, 1932); he named it after the planet Uranus, which had been discovered in 1781 by William Herschel, who named it after the ancient Greek deity of the Heavens.

  19. Biogeochemistry of uranium in the soil-plant and water-plant systems in an old uranium mine.

    PubMed

    Favas, Paulo J C; Pratas, João; Mitra, Soumita; Sarkar, Santosh Kumar; Venkatachalam, Perumal

    2016-10-15

    The present study highlights the uranium (U) concentrations in water-soil-plant matrices and the efficiency considering a heterogeneous assemblage of terrestrial and aquatic native plant species to act as the biomonitor and phytoremediator for environmental U-contamination in the Sevilha mine (uraniferous region of Beiras, Central Portugal). A total of 53 plant species belonging to 22 families was collected from 24 study sites along with ambient soil and/or water samples. The concentration of U showed wide range of variations in the ambient medium: 7.5 to 557mgkg(-1) for soil and 0.4 to 113μgL(-1) for water. The maximum potential of U accumulation was recorded in roots of the following terrestrial plants: Juncus squarrosus (450mgkg(-1) DW), Carlina corymbosa (181mgkg(-1) DW) and Juncus bufonius (39.9mgkg(-1) DW), followed by the aquatic macrophytes, namely Callitriche stagnalis (55.6mgkg(-1) DW) Lemna minor (53.0mgkg(-1) DW) and Riccia fluitans (50.6mgkg(-1) DW). Accumulation of U in plant tissues exhibited the following decreasing trend: root>leaves>stem>flowers/fruits and this confirms the unique efficiency of roots in accumulating this radionuclide from host soil/sediment (phytostabilization). Overall, the accumulation pattern in the studied aquatic plants (L. minor, R. fluitans, C. stagnalis and Lythrum portula) dominated over most of the terrestrial counterpart. Among terrestrial plants, the higher mean bioconcentration factor (≈1 in roots/rhizomes of C. corymbosa and J. squarrosus) and translocation factor (31 in Andryala integrifolia) were encountered in the representing families Asteraceae and Juncaceae. Hence, these terrestrial plants can be treated as the promising candidates for the development of the phytostabilization or phytoextraction methodologies based on the accumulation, abundance and biomass production.

  20. 10 CFR Appendix J to Part 110 - Illustrative List of Uranium Conversion Plant Equipment and Plutonium Conversion Plant Equipment...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... conversion of uranium fluorides to UO2. Many key equipment items for uranium conversion plants are common to... the hot effluent gases by passing the effluent stream through a cold trap cooled to -10°C. The process... common to several segments of the chemical process industry. For example, the types of equipment employed...

  1. 10 CFR Appendix J to Part 110 - Illustrative List of Uranium Conversion Plant Equipment and Plutonium Conversion Plant Equipment...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... conversion of uranium fluorides to UO2. Many key equipment items for uranium conversion plants are common to... the hot effluent gases by passing the effluent stream through a cold trap cooled to -10°C. The process... common to several segments of the chemical process industry. For example, the types of equipment employed...

  2. Uranium and radium concentrations in plants growing on uranium mill tailings in South Dakota

    Treesearch

    Mark A. Rumble; Ardell J. Bjugstad

    1986-01-01

    Vegetation and soil samples were collected from a uranium mill tailings site and control sites in South Dakota. Uranium concentrations in soils from the mill tailings averaged 13.3 [micro]g g-1 compared to 5.1 [micro]g g-1 in soils from control sites. 226Ra concentrations in soils averaged 111.0 pCi g...

  3. 10 CFR Appendix J to Part 110 - Illustrative List of Uranium Conversion Plant Equipment and Plutonium Conversion Plant Equipment...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... and Plutonium Conversion Plant Equipment Under NRC Export Licensing Authority J Appendix J to Part 110... Plutonium Conversion Plant Equipment Under NRC Export Licensing Authority Note: Uranium conversion plants... feed for electromagnetic enrichment. Note: Plutonium conversion plants and systems may perform one...

  4. 10 CFR Appendix J to Part 110 - Illustrative List of Uranium Conversion Plant Equipment and Plutonium Conversion Plant Equipment...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... and Plutonium Conversion Plant Equipment Under NRC Export Licensing Authority J Appendix J to Part 110... Plutonium Conversion Plant Equipment Under NRC Export Licensing Authority Note—Uranium conversion plants and... feed for electromagnetic enrichment. Note: Plutonium conversion plants and systems may perform one...

  5. Operating limit evaluation for disposal of uranium enrichment plant wastes

    SciTech Connect

    Lee, D.W.; Kocher, D.C.; Wang, J.C.

    1996-02-01

    A proposed solid waste landfill at Paducah Gaseous Diffusion Plant (PGDP) will accept wastes generated during normal plant operations that are considered to be non-radioactive. However, nearly all solid waste from any source or facility contains small amounts of radioactive material, due to the presence in most materials of trace quantities of such naturally occurring radionuclides as uranium and thorium. This paper describes an evaluation of operating limits, which are protective of public health and the environment, that would allow waste materials containing small amounts of radioactive material to be sent to a new solid waste landfill at PGDP. The operating limits are expressed as limits on concentrations of radionuclides in waste materials that could be sent to the landfill based on a site-specific analysis of the performance of the facility. These limits are advantageous to PGDP and DOE for several reasons. Most importantly, substantial cost savings in the management of waste is achieved. In addition, certain liabilities that could result from shipment of wastes to a commercial off-site solid waste landfill are avoided. Finally, assurance that disposal operations at the PGDP landfill are protective of public health and the environment is provided by establishing verifiable operating limits for small amounts of radioactive material; rather than relying solely on administrative controls. The operating limit determined in this study has been presented to the Commonwealth of Kentucky and accepted as a condition to be attached to the operating permit for the solid waste landfill.

  6. Uptake of Uranium and Other Elements of Concern by Plants Growing on Uranium Mill Tailings Disposal Cells

    NASA Astrophysics Data System (ADS)

    Joseph, C. N.; Waugh, W.; Glenn, E.

    2015-12-01

    The U.S. Department of Energy (DOE) is responsible for long-term stewardship of disposal cells for uranium mill tailings throughout the United States. Rock-armored disposal cell covers create favorable habitat for deep-rooted plants by reducing soil evaporation, increasing soil water storage, and trapping windblown dust, thereby providing water and nutrients for plant germination and establishment. DOE is studying the tradeoffs of potential detrimental and beneficial effects of plants growing on disposal cell covers to develop a rational and consistent vegetation management policy. Plant roots often extend vertically through disposal cell covers into underlying tailings, therefore, uptake of tailings contaminants and dissemination through animals foraging on stems and leaves is a possible exposure pathway. The literature shows that plant uptake of contaminants in uranium mill tailings occurs, but levels can vary widely depending on plant species, tailings and soil chemistry, and cover soil hydrology. Our empirical field study measured concentrations of uranium, radium, thorium, molybdenum, selenium, manganese, lead, and arsenic in above ground tissues harvested from plants growing on disposal cells near Native American communities in western states that represent a range of climates, cover designs, cover soil types, and vegetation types. For risk screening, contaminant levels in above ground tissues harvested from plants on disposal cells were compared to Maximum Tolerance Levels (MTLs) set for livestock by the National Research Council, and to tissue levels in the same plant species growing in reference areas near disposal cells. Although tailings were covered with uncontaminated soils, for 14 of 46 comparisons, levels of uranium and other contaminants were higher in plants growing on disposal cells compared to reference area plants, indicating possible mobilization of these elements from the tailing into plant tissues. However, with one exception, all plant

  7. Solubility Classification of Airborne Uranium Products from LWR-Fuel Plants

    SciTech Connect

    kalkwarf, D. R.

    1980-08-01

    Airborne dust samples were obtained from various locations within plants manufacturing fuel elements for light-water reactors, and the dissolution rates of uranium from these samples into simulated lung fluid at 37°C were measured. These measurements were used to classify the solubilities of the samples in terms of the lung clearance model proposed by the International Commission on Radiological Protection. Similar evaluations were performed for samples of pure uranium compounds expected as components in plant dust. The variation in solubility classifications of dust encountered along the fuel production lines is described and correlated with the process chemistry and the solubility classifications of the pure uranium compounds.

  8. The strategy on rehabilitation of the former uranium facilities at the 'Pridneprovsky chemical plant' in Ukraine

    SciTech Connect

    Voitsekhovich, O.; Lavrova, T.; Skalskiy, A.S.; Ryazantsev, V.F.

    2007-07-01

    This paper describes current status of the former Uranium Facilities at the Pridneprovsky Chemical Plant in Ukraine, which are currently under development of action plan for its territory rehabilitation. The monitoring data carried out during recent several years show its impact to the Environment and gives a basis for justification of the number of measures aiming to reduce radiological and ecological risks of the Uranium tailings situated at the territory of PChP. The monitoring data and strategy for its remediation are considered in the presentation. Uranium mining has been intensively conducted in Ukraine since the end of the 40-s. Most of the uranium deposits have been explored in the Dnieper river basin, while some smaller deposits can be found within the basins of the Southern Bug and Severskiy Donets rivers. There also several large Uranium Milling facilities were in operation since the end of the 40-s till 1991, when due to disintegration of the former Soviet Union system the own uranium production has been significantly declined. The Milling Plant and Uranium extraction Facilities in ZhevtiVody is still in operation with UkrAtomprom Industrial Consortium. Therefore rehabilitation programme for all Uranium facilities in this site are in duty of the East Mining Combine and the Consortium. The most difficult case is to provide rehabilitation Action Plan for Uranium tailings and number of other facilities situated in Dnieprodzerzhinsk town and which were in operation by the former State Industrial Enterprise Pridneprovskiy Chemical Plant (PChP). In past PChP was one of the largest Uranium Milling facilities of the Former Soviet Union and has been in operation since 1948 till 1991. During Soviet time the Uranium extraction at this legacy site has been carried out using the ore raw products delivered also from Central Asia, Germany and Checz Republic. After extraction the uranium residue has been putting to the nearest landscape depressions at the vicinity of

  9. Containment and storage of uranium hexafluoride at US Department of Energy uranium enrichment plants

    SciTech Connect

    Barlow, C.R.; Alderson, J.H.; Blue, S.C.; Boelens, R.A.; Conkel, M.E.; Dorning, R.E.; Ecklund, C.D.; Halicks, W.G.; Henson, H.M.; Newman, V.S.; Philpot, H.E.; Taylor, M.S.; Vournazos, J.P.; Russell, J.R.; Pryor, W.A.; Ziehlke, K.T.

    1992-07-01

    Isotopically depleted UF{sub 6} (uranium hexafluoride) accumulates at a rate five to ten times greater than the enriched product and is stored in steel vessels at the enrichment plant sites. There are approximately 55,000 large cylinders now in storage at Paducah, Kentucky; Portsmouth, Ohio; and Oak Ridge, Tennessee. Most of them contain a nominal 14 tons of depleted UF{sub 6}. Some of these cylinders have been in the unprotected outdoor storage environment for periods approaching 40 years. Storage experience, supplemented by limited corrosion data, suggests a service life of about 70 years under optimum conditions for the 48-in. diameter, 5/16-in.-wall pressure vessels (100 psi working pressure), using a conservative industry-established 1/4-in.-wall thickness as the service limit. In the past few years, however, factors other than atmospheric corrosion have become apparent that adversely affect the serviceability of small numbers of the storage containers and that indicate the need for a managed program to ensure maintenance ofcontainment integrity for all the cylinders in storage. The program includes periodic visual inspections of cylinders and storage yards with documentation for comparison with other inspections, a group of corrosion test programs to permit cylinder life forecasts, and identification of (and scheduling for remedial action) situations in which defects, due to handling damage or accelerated corrosion, can seriously shorten the storage life or compromise the containment integrity of individual cylinders. The program also includes rupture testing to assess the effects of certain classes of damage on overall cylinder strength, aswell as ongoing reviews of specifications, procedures, practices, and inspection results to effect improvements in handling safety, containment integrity, and storage life.

  10. Criteria for the safe storage of enriched uranium at the Y-12 Plant

    SciTech Connect

    Cox, S.O.

    1995-07-01

    Uranium storage practices at US Department of Energy (DOE) facilities have evolved over a period spanning five decades of programmatic work in support of the nuclear deterrent mission. During this period, the Y-12 Plant in Oak Ridge, Tennessee has served as the principal enriched uranium facility for fabrication, chemical processing, metallurgical processing and storage. Recent curtailment of new nuclear weapons production and stockpile reduction has created significant amounts of enriched uranium available as a strategic resource which must be properly and safely stored. This standard specifies criteria associated with the safe storage of enriched uranium at the Y-12 Plant. Because programmatic needs, compliance regulations and desirable materials of construction change with time, it is recommended that these standards be reviewed and amended periodically to ensure that they continue to serve their intended purpose.

  11. Position paper Oak Ridge Y-12 Plant storage of uranium in plastics

    SciTech Connect

    Duerksen, W.K.

    1995-07-01

    As a result of the end of the Cold War, the United States nuclear weapon stockpile is being reduced from approximately 20,000 warheads to fewer than 10,000 by the end of the century. The Oak Ridge Y-12 Plant is the Department of Energy (DOE) site charged with the responsibility of providing safe, secure storage for the uranium recovered from these weapons. In addition to weapons material, Y-12 has traditionally processed and stored uranium from nonweapon programs and presumably will continue to do so. The purpose of this document is to evaluate the suitability of plastics for use in the containment of uranium.

  12. Real-time monitoring of plutonium content in uranium-plutonium alloys

    DOEpatents

    Li, Shelly Xiaowei; Westphal, Brian Robert; Herrmann, Steven Douglas

    2015-09-01

    A method and device for the real-time, in-situ monitoring of Plutonium content in U--Pu Alloys comprising providing a crucible. The crucible has an interior non-reactive to a metallic U--Pu alloy within said interior of said crucible. The U--Pu alloy comprises metallic uranium and plutonium. The U--Pu alloy is heated to a liquid in an inert or reducing atmosphere. The heated U--Pu alloy is then cooled to a solid in an inert or reducing atmosphere. As the U--Pu alloy is cooled, the temperature of the U--Pu alloy is monitored. A solidification temperature signature is determined from the monitored temperature of the U--Pu alloy during the step of cooling. The amount of Uranium and the amount of Plutonium in the U--Pu alloy is then determined from the determined solidification temperature signature.

  13. Decontamination and decommissioning of the uranium mill and processing plant at Seelingstaedt, Germany

    SciTech Connect

    Barnekow, Ulf; Bauroth, Matthias; Paul, Michael

    2007-07-01

    In Eastern Germany uranium mining lasted from 1946 till 1990 including a production of in total 220,000 t of uranium. The Seelingstaedt Uranium Mill and Processing Plant, located in Thuringia, Germany, was one of two large uranium mills owned by Wismut. The mill was erected by 1960 and covered an area of 93 ha. From 1961 till 1991 a total of about 110 million t of different types of uranium ores were milled and processed at the Seelingstaedt mill. The mill produced ca. 110,000 t of uranium (in yellow cake). Demolition of the buildings and industrial facilities of the Seelingstaedt mill and processing plant site are nearly completed. The site is being decommissioned with respect to after-use aiming at afforestation and grasslands allowing for a stable plant succession. Decommissioning includes excavation and relocation of contaminated materials, reshaping of the site and construction of ditches for granting a stable surface runoff as well construction of access and maintenance roads. About 85% of the demolition and relocation works have been completed till to date. Last decommissioning works shall be completed by 2015. The present paper presents experiences made and progress achieved till to date. (authors)

  14. INTERNAL EXPOSURE TO URANIUM IN A POOLED COHORT OF GASEOUS DIFFUSION PLANT WORKERS

    PubMed Central

    Anderson, Jeri L.; Apostoaei, A. Iulian; Yiin, James H.; Fleming, Donald A.; Tseng, Chih-Yu; Chen, Pi-Hsueh

    2015-01-01

    Intakes and absorbed organ doses were estimated for 29 303 workers employed at three former US gaseous diffusion plants as part of a study of cause-specific mortality and cancer incidence in uranium enrichment workers. Uranium urinalysis data (>600 000 urine samples) were available for 58 % of the pooled cohort. Facility records provided uranium gravimetric and radioactivity concentration data and allowed estimation of enrichment levels of uranium to which workers may have been exposed. Urine data were generally recorded with facility department numbers, which were also available in study subjects’ work histories. Bioassay data were imputed for study subjects with no recorded sample results (33 % of pooled cohort) by assigning department average urine uranium concentration. Gravimetric data were converted to 24-h uranium activity excretion using department average specific activities. Intakes and organ doses were calculated assuming chronic exposure by inhalation to a 5-µm activity median aerodynamic diameter aerosol of soluble uranium. Median intakes varied between 0.31 and 0.74 Bq d−1 for the three facilities. Median organ doses for the three facilities varied between 0.019 and 0.051, 0.68 and 1.8, 0.078 and 0.22, 0.28 and 0.74, and 0.094 and 0.25 mGy for lung, bone surface, red bone marrow, kidneys, and liver, respectively. Estimated intakes and organ doses for study subjects with imputed bioassay data were similar in magnitude. PMID:26113578

  15. Linearity assumption in soil-to-plant transfer factors of natural uranium and radium in Helianthus annuus L.

    PubMed

    Rodríguez, P Blanco; Tomé, F Vera; Fernández, M Pérez; Lozano, J C

    2006-05-15

    The linearity assumption of the validation of soil-to-plant transfer factors of natural uranium and (226)Ra was tested using Helianthus annuus L. (sunflower) grown in a hydroponic medium. Transfer of natural uranium and (226)Ra was tested in both the aerial fraction of plants and in the overall seedlings (roots and shoots). The results show that the linearity assumption can be considered valid in the hydroponic growth of sunflowers for the radionuclides studied. The ability of sunflowers to translocate uranium and (226)Ra was also investigated, as well as the feasibility of using sunflower plants to remove uranium and radium from contaminated water, and by extension, their potential for phytoextraction. In this sense, the removal percentages obtained for natural uranium and (226)Ra were 24% and 42%, respectively. Practically all the uranium is accumulated in the roots. However, 86% of the (226)Ra activity concentration in roots was translocated to the aerial part.

  16. Systemic Lupus Erythematosus is Associated with Uranium Exposure in a Community Living Near a Uranium Processing Plant: A Nested Case-Control Study

    PubMed Central

    Lu-Fritts, Pai-Yue; Kottyan, Leah C.; James, Judith A.; Xie, Changchung; Buckholz, Jeanette M.; Pinney, Susan M.; Harley, John B.

    2014-01-01

    Objective Explore the hypothesis that cases of SLE will be found more frequently in community members with high prior uranium exposure in the Fernald Community Cohort (FCC). Methods A nested case control study was performed. The FCC is a volunteer population that lived near a uranium ore processing plant in Fernald, Ohio, USA during plant operation and members were monitored for 18 years. Uranium plant workers were excluded. SLE cases were identified using American College of Rheumatology classification criteria, laboratory testing, and medical record review. Each case was matched to four age-, race-, and sex-matched controls. Sera from potential cases and controls were screened for autoantibodies. Cumulative uranium particulate exposure was calculated using a dosimetry model. Logistic regression with covariates was used to calculate odds ratios (OR) with 95% confidence intervals (CI). Results The FCC includes 4,187 individuals with background uranium exposure, 1,273 with moderate exposure, and 2,756 with higher exposure. SLE was confirmed in 23 of 31 individuals with a lupus ICD9 code, and in 2 of 43 other individuals prescribed hydroxychloroquine. The female:male ratio was 5.25:1. Of the 25 SLE cases, 12 were in the higher exposure group. SLE was associated with higher uranium exposure (OR 3.92, 95% CI 1.131-13.588, p = 0.031). Conclusion High uranium exposure is associated with SLE relative to matched controls in this sample of uranium exposed individuals. Potential explanations for this relationship include possible autoimmune or estrogen effects of uranium, somatic mutation, epigenetic effects, or effects of some other unidentified accompanying exposure. PMID:25103365

  17. Real-time measurement of electron beam weld penetration in uranium by acoustic emission monitoring

    SciTech Connect

    Whittaker, J.W.; Murphy, J.L.

    1991-07-01

    High quality electron beam (EB) welds are required in uranium test articles. Acoustic emission (AE) techniques are under development with the goal of measuring weld penetration in real-time. One technique, based on Average Signal Level (ASL) measurement was used to record weld AE signatures. Characteristic AE signatures were recorded for bead-on-plate (BOP) and butt joint (BJ) welds made under varied welding conditions. AE waveforms were sampled to determine what microscopic AE behavior led to the observed macroscopic signature features. Deformation twinning and weld expulsion are two of the main sources of emission. AE behavior was correlated with weld penetration as measured by standard metallographic techniques. The ASL value was found to increase approximately linearly with weld penetration in BJ welds. These results form the basis for a real-time monitoring technique for weld penetration. 5 refs.

  18. Surface Decontamination of System Components in Uranium Conversion Plant at KAERI

    SciTech Connect

    Choi, W. K.; Kim, K. N.; Won, H. J.; Jung, C. H.; Oh, W. Z.

    2003-02-25

    A chemical decontamination process using nitric acid solution was selected as in-situ technology for recycle or release with authorization of a large amount of metallic waste including process system components such as tanks, piping, etc., which is generated by dismantling a retired uranium conversion plant at Korea Atomic Energy Research Institute (KAERI). The applicability of nitric acid solution for surface decontamination of metallic wastes contaminated with uranium compounds was evaluated through the basic research on the dissolution of UO2 and ammonium uranyl carbonate (AUC) powder. Decontamination performance was verified by using the specimens contaminated with such uranium compounds as UO2 and AUC taken from the uranium conversion plant. Dissolution rate of UO2 powder is notably enhanced by the addition of H2O2 as an oxidant even in the condition of a low concentration of nitric acid and low temperature compared with those in a nitric acid solution without H2O2. AUC powders dissolve easily in nitric acid solutions until the solution pH attains about 2.5 {approx} 3. Above that solution pH, however, the uranium concentration in the solution is lowered drastically by precipitation as a form of U3(NH3)4O9 . 5H2O. Decontamination performance tests for the specimens contaminated with UO2 and AUC were quite successful with the application of decontamination conditions obtained through the basic studies on the dissolution of UO2 and AUC powders.

  19. Uranium deposit removal from the Oak Ridge Gaseous Diffusion Plant K-25 Building

    SciTech Connect

    Ladd, L.D.; Stinnett, E.C. Jr.; Hale, J.R. ); Haire, M.J. )

    1993-01-01

    The Oak Ridge Gaseous Diffusion Plant went into operation as the first plant to separate uranium by the gaseous diffusion process. It was built during World War II as part of the U.S. Army Corps of Engineers' Manhattan Project. Its war-time code name was K-25, which was also the name of the first uranium separation building constructed at the installation. The K-25 building was considered an engineering miracle at the time of its construction. Built in a U shape [approximately]1 mile long and 400 ft wide, it housed complex and unique separation equipment. Despite its size and complexity, it was made fully operational within <2 yr after construction began. The facility operated successfully for more than 20 yr until it was placed in a standby mode in 1964. It is now clear the K-25 gaseous diffusion plant will never again be used to enrich uranium. The U.S. Department of Energy, therefore, has initiated a decontamination and decommission program. This paper discusses various procedures and techniques for addressing critical mass, uranium deposits, and safeguards issues.

  20. Internal exposure to uranium in a pooled cohort of gaseous diffusion plant workers.

    PubMed

    Anderson, Jeri L; Apostoaei, A Iulian; Yiin, James H; Fleming, Donald A; Tseng, Chih-Yu; Chen, Pi-Hsueh

    2016-03-01

    Intakes and absorbed organ doses were estimated for 29 303 workers employed at three former US gaseous diffusion plants as part of a study of cause-specific mortality and cancer incidence in uranium enrichment workers. Uranium urinalysis data (>600 000 urine samples) were available for 58 % of the pooled cohort. Facility records provided uranium gravimetric and radioactivity concentration data and allowed estimation of enrichment levels of uranium to which workers may have been exposed. Urine data were generally recorded with facility department numbers, which were also available in study subjects' work histories. Bioassay data were imputed for study subjects with no recorded sample results (33 % of pooled cohort) by assigning department average urine uranium concentration. Gravimetric data were converted to 24-h uranium activity excretion using department average specific activities. Intakes and organ doses were calculated assuming chronic exposure by inhalation to a 5-µm activity median aerodynamic diameter aerosol of soluble uranium. Median intakes varied between 0.31 and 0.74 Bq d(-1) for the three facilities. Median organ doses for the three facilities varied between 0.019 and 0.051, 0.68 and 1.8, 0.078 and 0.22, 0.28 and 0.74, and 0.094 and 0.25 mGy for lung, bone surface, red bone marrow, kidneys, and liver, respectively. Estimated intakes and organ doses for study subjects with imputed bioassay data were similar in magnitude. Published by Oxford University Press 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  1. Environmental impact of uranium mining and ore processing in the Lagoa Real District, Bahia, Brazil.

    PubMed

    Carvalho, Ilson G; Cidu, Rosa; Fanfani, Luca; Pitsch, Helmut; Beaucaire, Catherine; Zuddas, Pierpaolo

    2005-11-15

    Uranium mining and processing at Lagoa Real (Bahia, Brazil) started in 2000. Hydrogeochemical monitoring carried out from 1999 to 2001 revealed generally good quality of the water resources outside and inside the mineralized area. No chemical contamination in waters for domestic uses was observed. Hydrochemical characteristics did not vary significantly after 1 year of U exploitation, as compared to premining conditions. Due to the short time of mining, the results cannot exclude future variations in water quality. Leaching experiments helped to describe processes of ore and waste degradation. Sulfate was identified as an indicator for different types of contamination. Potential hazards related to local climate (hot rainy season) were identified. They indicate that tailings derived from the ore processing, destabilized by sulfuric acid attack, may induce acidification and salinization in the surrounding environment. Another potential source of environmental impact could be linked to local radium-rich mineralization, originating radon emission.

  2. A study on possible use of Urtica dioica (common nettle) plants as uranium ((234)U, (238)U) contamination bioindicator near phosphogypsum stockpile.

    PubMed

    Olszewski, Grzegorz; Boryło, Alicja; Skwarzec, Bogdan

    The aim of this study was to determine uranium concentrations in common nettle (Urtica dioica) plants and corresponding soils samples which were collected from the area of phosphogypsum stockpile in Wiślinka (northern Poland). The uranium concentrations in roots depended on its concentrations in soils. Calculated BCF and TF values showed that soils characteristics and air deposition affect uranium absorption and that different uranium species have different affinities to U. dioica plants. The values of (234)U/(238)U activity ratio indicate natural origin of these radioisotopes in analyzed plants. Uranium concentration in plants roots is negatively weakly correlated with distance from phosphogypsum stockpile.

  3. Screening of plant species for phytoremediation of uranium, thorium, barium, nickel, strontium and lead contaminated soils from a uranium mill tailings repository in South China.

    PubMed

    Li, Guang-yue; Hu, Nan; Ding, De-xin; Zheng, Ji-fang; Liu, Yu-long; Wang, Yong-dong; Nie, Xiao-qin

    2011-06-01

    The concentrations of uranium, thorium, barium, nickel, strontium and lead in the samples of the tailings and plant species collected from a uranium mill tailings repository in South China were analyzed. Then, the removal capability of a plant for a target element was assessed. It was found that Phragmites australis had the greatest removal capabilities for uranium (820 μg), thorium (103 μg) and lead (1,870 μg). Miscanthus floridulus had the greatest removal capabilities for barium (3,730 μg) and nickel (667 μg), and Parthenocissus quinquefolia had the greatest removal capability for strontium (3,920 μg). In this study, a novel coefficient, termed as phytoremediation factor (PF), was proposed, for the first time, to assess the potential of a plant to be used in phytoremediation of a target element contaminated soil. Phragmites australis has the highest PFs for uranium (16.6), thorium (8.68), barium (10.0) and lead (10.5). Miscanthus floridulus has the highest PF for Ni (25.0). Broussonetia papyrifera and Parthenocissus quinquefolia have the relatively high PFs for strontium (28.1 and 25.4, respectively). On the basis of the definition for a hyperaccumulator, only Cyperus iria and Parthenocissus quinquefolia satisfied the criteria for hyperaccumulator of uranium (36.4 μg/g) and strontium (190 μg/g), and could be the candidates for phytoremediation of uranium and strontium contaminated soils. The results show that the PF has advantage over the hyperaccumulator in reflecting the removal capabilities of a plant for a target element, and is more adequate for assessing the potential of a plant to be used in phytoremediation than conventional method.

  4. Characterization of past and present solid waste streams from the Plutonium-Uranium Extraction Plant

    SciTech Connect

    Pottmeyer, J.A.; Weyns, M.I.; Lorenzo, D.S.; Vejvoda, E.J.; Duncan, D.R.

    1993-04-01

    During the next two decades the transuranic wastes, now stored in the burial trenches and storage facilities at the Hanford Site, are to be retrieved, processed at the Waste Receiving and Processing Facility, and shipped to the Waste Isolation Pilot Plant near Carlsbad, New Mexico for final disposal. Over 7% of the transuranic waste to be retrieved for shipment to the Waste Isolation Pilot Plant has been generated at the Plutonium-Uranium Extraction (PUREX) Plant. The purpose of this report is to characterize the radioactive solid wastes generated by PUREX using process knowledge, existing records, and oral history interviews. The PUREX Plant is currently operated by the Westinghouse Hanford Company for the US Department of Energy and is now in standby status while being prepared for permanent shutdown. The PUREX Plant is a collection of facilities that has been used primarily to separate plutonium for nuclear weapons from spent fuel that had been irradiated in the Hanford Site`s defense reactors. Originally designed to reprocess aluminum-clad uranium fuel, the plant was modified to reprocess zirconium alloy clad fuel elements from the Hanford Site`s N Reactor. PUREX has provided plutonium for research reactor development, safety programs, and defense. In addition, the PUREX was used to recover slightly enriched uranium for recycling into fuel for use in reactors that generate electricity and plutonium. Section 2.0 provides further details of the PUREX`s physical plant and its operations. The PUREX Plant functions that generate solid waste are as follows: processing operations, laboratory analyses and supporting activities. The types and estimated quantities of waste resulting from these activities are discussed in detail.

  5. Cost update technology, safety, and costs of decommissioning a reference uranium hexafluoride conversion plant

    SciTech Connect

    Miles, T.L.; Liu, Y.

    1995-08-01

    The purpose of this study is to update the cost estimates developed in a previous report, NUREG/CR-1757 (Elder 1980) for decommissioning a reference uranium hexafluoride conversion plant from the original mid-1981 dollars to values representative of January 1993. The cost updates were performed by using escalation factors derived from cost index trends over the past 11.5 years. Contemporary price quotes wee used for costs that have increased drastically or for which is is difficult to find a cost trend. No changes were made in the decommissioning procedures or cost element requirements assumed in NUREG/CR-1757. This report includes only information that was changed from NUREG/CR-1757. Thus, for those interested in detailed descriptions and associated information for the reference uranium hexafluoride conversion plant, a copy of NUREG/CR-1757 will be needed.

  6. Evaluation of a RF-Based Approach for Tracking UF6 Cylinders at a Uranium Enrichment Plant

    SciTech Connect

    Pickett, Chris A; Younkin, James R; Kovacic, Donald N; Laughter, Mark D; Hines, Jairus B; Boyer, Brian; Martinez, B.

    2008-01-01

    Approved industry-standard cylinders are used globally to handle and store uranium hexafluoride (UF{sub 6}) feed, product, tails, and samples at uranium enrichment plants. The International Atomic Energy Agency (IAEA) relies on time-consuming physical inspections to verify operator declarations and detect possible diversion of UF{sub 6}. Development of a reliable, automated, and tamper-resistant system for near real-time tracking and monitoring UF{sub 6} cylinders (as they move within an enrichment facility) would greatly improve the inspector function. This type of system can reduce the risk of false or misreported cylinder tare weights, diversion of nuclear material, concealment of excess production, utilization of undeclared cylinders, and misrepresentation of the cylinders contents. This paper will describe a proof-of-concept approach that was designed to evaluate the feasibility of using radio frequency (RF)-based technologies to track individual UF{sub 6} cylinders throughout a portion of their life cycle, and thus demonstrate the potential for improved domestic accountability of materials, and a more effective and efficient method for application of site-level IAEA safeguards. The evaluation system incorporates RF-based identification devices (RFID) which provide a foundation for establishing a reliable, automated, and near real-time tracking system that can be set up to utilize site-specific, rules-based detection algorithms. This paper will report results from a proof-of-concept demonstration at a real enrichment facility that is specifically designed to evaluate both the feasibility of using RF to track cylinders and the durability of the RF equipment to survive the rigors of operational processing and handling. The paper also discusses methods for securely attaching RF devices and describes how the technology can effectively be layered with other safeguard systems and approaches to build a robust system for detecting cylinder diversion. Additionally

  7. Radon transport from uranium mill tailings via plant transpiration. Final report

    SciTech Connect

    Lewis, B.A.G.

    1985-01-01

    Radon exhalation by vegetation planted on bare or soil-covered uranium mill wastes was studied based on an assumption that radon transport from soil to atmosphere via plants takes place in the transpiration stream. Results show that radon exhalation by plants is inversely related to water transpired, primarily a dilution effect. Radon released appeared directly related to leaf area, suggesting that radon is carried into the plant by mass flow in water; however, once within the plant, radon very likely diffuses through the entire leaf cuticle, while water vapor diffuses primarily through open stomates. Application of a computerized model for water transpiration to radon exhalation is not immediately useful until the role of water in radon transport is defined throughout the continuum from rooting medium to the atmosphere. Until then, a simple calculation based on leaf area index and Ra-226 concentration in the rooting medium can provide an estimate of radon release from revegetated wastes containing radium.

  8. Model of a Generic Natural Uranium Conversion Plant ? Suggested Measures to Strengthen International Safeguards

    SciTech Connect

    Raffo-Caiado, Ana Claudia; Begovich, John M; Ferrada, Juan J

    2009-11-01

    This is the final report that closed a joint collaboration effort between DOE and the National Nuclear Energy Commission of Brazil (CNEN). In 2005, DOE and CNEN started a collaborative effort to evaluate measures that can strengthen the effectiveness of international safeguards at a natural uranium conversion plant (NUCP). The work was performed by DOE s Oak Ridge National Laboratory and CNEN. A generic model of a NUCP was developed and typical processing steps were defined. Advanced instrumentation and techniques for verification purposes were identified and investigated. The scope of the work was triggered by the International Atomic Energy Agency s 2003 revised policy concerning the starting point of safeguards at uranium conversion facilities. Prior to this policy only the final products of the uranium conversion plant were considered to be of composition and purity suitable for use in the nuclear fuel cycle and therefore, subject to the IAEA safeguards control. DOE and CNEN have explored options for implementing the IAEA policy, although Brazil understands that the new policy established by the IAEA is beyond the framework of the Quadripartite Agreement of which it is one of the parties, together with Argentina, the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) and the IAEA. Two technical papers on this subject were published at the 2005 and 2008 INMM Annual Meetings.

  9. Accumulation of uranium by aquatic plants in field conditions: prospects for phytoremediation.

    PubMed

    Favas, Paulo J C; Pratas, João; Varun, Mayank; D'Souza, Rohan; Paul, Manoj S

    2014-02-01

    A study was undertaken to determine Uranium concentrations in water and aquatic plants in the uraniferous region of Beiras, Central Portugal. Samples were collected from running water (n=200) at places where aquatic species were observed. Plant samples were collected from 28 species of submerged, free-floating and rooted emergent plants including 2 bryophytes and 1 pteridophyte. Uranium concentrations in surface waters ranged from 0.23 to 1,217 μg L(-1). The aquatic plant species studied, including several previously untested species, exhibited the ability to accumulate U in concentrations many times that of the ambient water. In general submerged plants exhibited higher U content followed by rooted emergent and free floating species. The highest U concentrations were observed in the bryophyte Fontinalis antipyretica (up to 4,979 mg kg(-1)) followed by Callitriche stagnalis (1963mgkg(-1)), Callitriche hamulata (379 mg kg(-1)), Ranunculus peltatus subsp. saniculifolius (243 mg kg(-1)), Callitriche lusitanica (218 mg kg(-1)), and Ranunculus trichophyllus (65.8 mg kg(-1)). In two out of three rooted emergent species U seemed to be preferentially partitioned in rhizome/roots with highest rhizome U content recorded in Typha latifolia (380 mg kg(-1)). Among the free-floating species, the highest U content (42.5 mg kg(-1)) was seen in Lemna minor. The bryophyte F. antipyretica and Callitrichaceae members seem to be promising candidates for the development of phytofiltration methodologies based on U accumulation, abundance and biomass production.

  10. Decontamination and Decommissioning Experience at a Sellafield Uranium Purification Plant

    SciTech Connect

    Prosser, J.L.

    2006-07-01

    Built in the 1950's, this plant was originally designed to purify depleted uranyl nitrate solution arising from reprocessing operations at the Primary Separation and Head End Plant (Fig. 1). The facility was used for various purposes throughout its life cycle such as research, development and trial based processes. Test rigs were operated in the building from the 1970's until 1984 to support development of the process and equipment now used at Sellafield's Thermal Oxide Reprocessing Plant (THORP). The extensive decommissioning program for this facility began over 15 years ago. Many challenges have been overcome throughout this program such as decommissioning the four main process cells, which were very highly alpha contaminated. The cells contained vessels and pipeline systems that were contaminated to such levels that workers had to use pressurized suits to enter the cells. Since decommissioning at Sellafield was in its infancy, this project has trialed various decontamination/decommissioning methods and techniques in order to progress the project, and this has provided valuable learning for other decommissioning projects. The project has included characterization, decontamination, dismantling, waste handling, and is now ready for demolition during late 2005, early 2006. This will be the first major facility within the historic Separation Area at Sellafield to be demolished down to base slab level. The lessons learnt from this project will directly benefit numerous decommissioning projects as the cleanup at Sellafield continues. (authors)

  11. The New Generation of Uranium In Situ Recovery Facilities: Design Improvements Should Reduce Radiological Impacts Relative to First Generation Uranium Solution Mining Plants

    SciTech Connect

    Brown, S.H.

    2008-07-01

    In the last few years, there has been a significant increase in the demand for Uranium as historical inventories have been consumed and new reactor orders are being placed. Numerous mineralized properties around the world are being evaluated for Uranium recovery and new mining / milling projects are being evaluated and developed. Ore bodies which are considered uneconomical to mine by conventional methods such as tunneling or open pits, can be candidates for non-conventional recovery techniques, involving considerably less capital expenditure. Technologies such as Uranium In Situ Leaching / In Situ Recovery (ISL / ISR - also referred to as 'solution mining'), have enabled commercial scale mining and milling of relatively small ore pockets of lower grade, and are expected to make a significant contribution to overall world wide uranium supplies over the next ten years. Commercial size solution mining production facilities have operated in the US since the mid 1970's. However, current designs are expected to result in less radiological wastes and emissions relative to these 'first' generation plants (which were designed, constructed and operated through the 1980's). These early designs typically used alkaline leach chemistries in situ including use of ammonium carbonate which resulted in groundwater restoration challenges, open to air recovery vessels and high temperature calcining systems for final product drying vs the 'zero emissions' vacuum dryers as typically used today. Improved containment, automation and instrumentation control and use of vacuum dryers in the design of current generation plants are expected to reduce production of secondary waste byproduct material, reduce Radon emissions and reduce potential for employee exposure to uranium concentrate aerosols at the back end of the milling process. In Situ Recovery in the U.S. typically involves the circulation of groundwater, fortified with oxidizing (gaseous oxygen e.g) and complexing agents (carbon

  12. Assessing depleted uranium (DU) contamination of soil, plants and earthworms at UK weapons testing sites.

    PubMed

    Oliver, Ian W; Graham, Margaret C; MacKenzie, Angus B; Ellam, Robert M; Farmer, John G

    2007-07-01

    Depleted uranium (DU) weapons testing programmes have been conducted at two locations within the UK. An investigation was therefore carried out to assess the extent of any environmental contamination arising from these test programmes using both alpha spectrometry and mass spectrometry techniques. Uranium isotopic signatures indicative of DU contamination were observed in soil, plant and earthworm samples collected in the immediate vicinity of test firing points and targets, but contamination was found to be localised to these areas. This paper demonstrates the superiority of the (235)U : (238)U ratio over the (234)U : (238)U ratio for identifying and quantifying DU contamination in environmental samples, and also describes the respective circumstances under which alpha spectrometry or mass spectrometry may be the more appropriate analytical tool.

  13. Performance acceptance test of a portable instrument to detect uranium in water at the DOE Advanced Waste Water Treatment Plant, Fernald, Ohio

    SciTech Connect

    Anderson, M.S.; Weeks, S.J.

    1997-03-28

    The Eppendorf-Biotronik Model IC 2001-2, a portable field ruggedized ion chromatography instrument, was rigorously tested at the DOE Advanced Waste Water Treatment Plant, Fernald, Ohio. This instrument rapidly detected the uranium concentration in water, and has a detection limit in the low ppb range without using the sample concentrating feature. The test set of samples analyzed included: ``Real World`` water samples from the AWWT containing uranium concentrations in the 9--110 ppb range, a sample blank, and a performance evaluation sample. The AWWT samples contained sets of both raw water and acid-preserved water samples. Selected samples were analyzed in quadruplicate to asses the instrument`s precision, and these results were compared with the results from an off-site confirmatory laboratory to assess the instrument`s accuracy. Additional comparisons with on-site laboratory instruments, Chemcheck KPA-11 and Scintrex UA-3 are reported. Overall, the Eppendorf-Biotronik IC 2001-2 performed exceptionally well providing a detection limit in the low ppb region (< 10 ppb) and giving rapid (< 5 minutes) accurate and reproducible analytical results for the AWWT, ``real world``, water samples with uranium concentrations in the region of interest (10--40 ppb). The per sample operating cost for this instrument is equivalent to the per sample cost for the currently used KPA. The time required to analyze a sample and provide a result is approximately the same for the CI 2001-2, KPA, and Scintrex instruments.

  14. Case-control study of lung cancer among workers at a uranium processing plant

    SciTech Connect

    Cookfair, D.L.

    1982-01-01

    The purpose of this case-control study was to investigate the relationship between exposure to radiation resulting from the inhalation of uranium dust and the dust of uranium-bearing compounds and death due to lung cancer. Cases and controls were chosen from a cohort of white male workers employed at one uranium processing plant during World War II. The 330 cases consisted of all lung cancer deaths occurring in the cohort between 1943 and 1973. Level of exposure to radiation and other potential workplace carcinogens was determined for each worker using process manuals, industrial hygiene reports, air monitoring data and individual work histories. Smoking status and information regarding medical variables was determined from employee medical records. Cumulative radiation lung dose among study population members ranged from 0 to 75 rads. Data were analyzed using Mantel-Haenszel stratified analysis and logistic regression. Relative risk was found to increase with increasing level of lung dose exposure even after controlling for age, smoking status and other workplace exposures, but only for those who were over the age of 44 when first exposed. A statistically significant excess in risk was found for men in this hire age group with a cumulative lung dose of 20 rads or more. The risk associated with the overall work environment was also investigated using a summary measure of total workplace exposure called chemical rank. A similar relationship existed between chemical rank and lung cancer to that found for cumulative lung dose and lung cancer.

  15. Spectroscopic evidence of uranium immobilization in acidic wetlands by natural organic matter and plant roots

    DOE PAGES

    Li, Dien; Kaplan, Daniel I.; Chang, Hyun-Shik; ...

    2015-03-03

    Biogeochemistry of uranium in wetlands plays important roles in U immobilization in storage ponds of U mining and processing facilities but has not been well understood. The objective of this work was to study molecular mechanisms responsible for high U retention by Savannah River Site (SRS) wetland sediments under varying redox and acidic (pH = 2.6–5.8) conditions using U L₃-edge X-ray absorption spectroscopy. Uranium in the SRS wetland sediments existed primarily as U(VI) bonded as a bidentate to carboxylic sites (U–C bond distance at ~2.88 Å), rather than phenolic or other sites of natural organic matter (NOM). In microcosms simulatingmore » the SRS wetland processes, U immobilization on roots was two orders of magnitude higher than on the adjacent brown or more distant white sands in which U was U(VI). Uranium on the roots were both U(IV) and U(VI), which were bonded as a bidentate to carbon, but the U(VI) may also form a U phosphate mineral. After 140 days of air exposure, all U(IV) was re-oxidized to U(VI) but remained as a bidentate bonding to carbon. This study demonstrated NOM and plant roots can highly immobilize U(VI) in the SRS acidic sediments, which has significant implication for the long-term stewardship of U-contaminated wetlands.« less

  16. Spectroscopic evidence of uranium immobilization in acidic wetlands by natural organic matter and plant roots

    SciTech Connect

    Li, Dien; Kaplan, Daniel I.; Chang, Hyun-Shik; Seaman, John C.; Jaffé, Peter R.; Koster van Groos, Paul; Scheckel, Kirk G.; Segre, Carlo U.; Chen, Ning; Jiang, De-Tong; Newville, Matthew; Lanzirotti, Antonio

    2015-03-03

    Biogeochemistry of uranium in wetlands plays important roles in U immobilization in storage ponds of U mining and processing facilities but has not been well understood. The objective of this work was to study molecular mechanisms responsible for high U retention by Savannah River Site (SRS) wetland sediments under varying redox and acidic (pH = 2.6–5.8) conditions using U L₃-edge X-ray absorption spectroscopy. Uranium in the SRS wetland sediments existed primarily as U(VI) bonded as a bidentate to carboxylic sites (U–C bond distance at ~2.88 Å), rather than phenolic or other sites of natural organic matter (NOM). In microcosms simulating the SRS wetland processes, U immobilization on roots was two orders of magnitude higher than on the adjacent brown or more distant white sands in which U was U(VI). Uranium on the roots were both U(IV) and U(VI), which were bonded as a bidentate to carbon, but the U(VI) may also form a U phosphate mineral. After 140 days of air exposure, all U(IV) was re-oxidized to U(VI) but remained as a bidentate bonding to carbon. This study demonstrated NOM and plant roots can highly immobilize U(VI) in the SRS acidic sediments, which has significant implication for the long-term stewardship of U-contaminated wetlands.

  17. Spectroscopic evidence of uranium immobilization in acidic wetlands by natural organic matter and plant roots.

    PubMed

    Li, Dien; Kaplan, Daniel I; Chang, Hyun-Shik; Seaman, John C; Jaffé, Peter R; Koster van Groos, Paul; Scheckel, Kirk G; Segre, Carlo U; Chen, Ning; Jiang, De-Tong; Newville, Matthew; Lanzirotti, Antonio

    2015-03-03

    Biogeochemistry of uranium in wetlands plays important roles in U immobilization in storage ponds of U mining and processing facilities but has not been well understood. The objective of this work was to study molecular mechanisms responsible for high U retention by Savannah River Site (SRS) wetland sediments under varying redox and acidic (pH = 2.6-5.8) conditions using U L3-edge X-ray absorption spectroscopy. Uranium in the SRS wetland sediments existed primarily as U(VI) bonded as a bidentate to carboxylic sites (U-C bond distance at ∼2.88 Å), rather than phenolic or other sites of natural organic matter (NOM). In microcosms simulating the SRS wetland processes, U immobilization on roots was 2 orders of magnitude higher than on the adjacent brown or more distant white sands in which U was U(VI). Uranium on the roots were both U(IV) and U(VI), which were bonded as a bidentate to carbon, but the U(VI) may also form a U phosphate mineral. After 140 days of air exposure, all U(IV) was reoxidized to U(VI) but remained as a bidentate bonding to carbon. This study demonstrated NOM and plant roots can highly immobilize U(VI) in the SRS acidic sediments, which has significant implication for the long-term stewardship of U-contaminated wetlands.

  18. Preconceptual design studies and cost data of depleted uranium hexafluoride conversion plants

    SciTech Connect

    Jones, E

    1999-07-26

    One of the more important legacies left with the Department of Energy (DOE) after the privatization of the United States Enrichment Corporation is the large inventory of depleted uranium hexafluoride (DUF6). The DOE Office of Nuclear Energy, Science and Technology (NE) is responsible for the long-term management of some 700,000 metric tons of DUF6 stored at the sites of the two gaseous diffusion plants located at Paducah, Kentucky and Portsmouth, Ohio, and at the East Tennessee Technology Park in Oak Ridge, Tennessee. The DUF6 management program resides in NE's Office of Depleted Uranium Hexafluoride Management. The current DUF6 program has largely focused on the ongoing maintenance of the cylinders containing DUF6. However, the long-term management and eventual disposition of DUF6 is the subject of a Programmatic Environmental Impact Statement (PEIS) and Public Law 105-204. The first step for future use or disposition is to convert the material, which requires construction and long-term operation of one or more conversion plants. To help inform the DUF6 program's planning activities, it was necessary to perform design and cost studies of likely DUF6 conversion plants at the preconceptual level, beyond the PEIS considerations but not as detailed as required for conceptual designs of actual plants. This report contains the final results from such a preconceptual design study project. In this fast track, three month effort, Lawrence Livermore National Laboratory and Bechtel National Incorporated developed and evaluated seven different preconceptual design cases for a single plant. The preconceptual design, schedules, costs, and issues associated with specific DUF6 conversion approaches, operating periods, and ownership options were evaluated based on criteria established by DOE. The single-plant conversion options studied were similar to the dry-conversion process alternatives from the PEIS. For each of the seven cases considered, this report contains information on

  19. Measurements of uranium holdup in an operating gaseous diffusion enrichment plant

    SciTech Connect

    Augustson, R.H.; Walton, R.B.; Harris, R.; Harbarger, W.; Hicks, J.; Timmons, G.; Shissler, D.; Tayloe, R.; Jones, S.; Fields, L.

    1983-01-01

    Holdup of nuclear material in process equipment is one of the major sources of uncertainty in materials balances, particularly for high-throughput facilities with large equipment and extensive piping, such as gaseous diffusion uranium-enrichment plants. Locating and measuring the holdup while the plant is operating is a challenging problem because of background from the process material and the neighboring equipment. This paper reports NDA measurements performed at the Goodyear Atomic Gaseous Diffusion Plant, Portsmouth, Ohio, on enrichment equipment at the higher enrichment and (>10% /sup 235/U isotopic abundance) of the cascade. Both neutron and gamma-ray measurements were made to locate anomalously large deposits in converters and compressors and, within the limitations of the techniques, to quantify the amount of the deposit.

  20. 226Ra bioavailability to plants at the Urgeiriça uranium mill tailings site.

    PubMed

    Madruga, M J; Brogueira, A; Alberto, G; Cardoso, F

    2001-01-01

    Large amounts of solid wastes (tailings) resulting from the exploitation and treatment of uranium ore at the Urgeiriça mine (north of Portugal) have been accumulated in dams (tailing ponds). To reduce the dispersion of natural radionuclides into the environment, some dams were revegetated with eucalyptus (Eucalyptus globolus) and pines (Pinus pinea). Besides these plants, some shrubs (Cytisus spp.) are growing in some of the dams. The objective of this study is to determine the 226Ra bioavailability from uranium mill tailings by quantifying the total and available fraction of radium in the tailings and to estimate its transfer to plants growing on the tailing piles. Plant and tailing samples were randomly collected and the activity concentration of 226Ra in plants (aerial part and roots) and tailings was measured by gamma-spectrometry. The exchangeable fraction of radium in tailings was quantified using one single step extraction with 1 mol dm-3 ammonium acetate (pH = 7) or 1 mol dm-3 calcium chloride solutions. The results obtained for 226Ra uptake by plants show that 226Ra concentration ratios for eucalyptus and pines decrease at low 226Ra concentrations in the tailings and appear relatively constant at higher radium concentrations. For shrubs, the concentration ratios increase at higher 226Ra solid waste concentrations approaching a saturation value. Percentage values of 16.0 +/- 8.3 and 12.9 +/- 8.9, for the fraction of radium extracted from the tailings, using 1 mol dm-3 ammonium acetate or calcium chloride solutions, respectively, were obtained. The 226Ra concentration ratios determined on the basis of exchangeable radium are one order of magnitude higher than those based on total radium. It can be concluded that, at a 95% confidence level, more consistent 226Ra concentration ratios were obtained when calculated on the basis of available radium than when total radium was considered, for all the dams.

  1. History of Uranium-233(sup233U)Processing at the Rocky Flats Plant. In support of the RFETS Acceptable Knowledge Program

    SciTech Connect

    Moment, R.L.; Gibbs, F.E.; Freiboth, C.J.

    1999-04-01

    This report documents the processing of Uranium-233 at the Rocky Flats Plant (Rocky Flats Environmental Technology Site). The information may be used to meet Waste Isolation Pilot Plant (WIPP) Waste Acceptance Criteria (WAC)and for determining potential Uranium-233 content in applicable residue waste streams.

  2. BIO-MONITORING FOR URANIUM USING STREAM-SIDE TERRESTRIAL PLANTS AND MACROPHYTES

    SciTech Connect

    Caldwell, E.; Duff, M.; Hicks, T.; Coughlin, D.; Hicks, R.; Dixon, E.

    2012-01-12

    This study evaluated the abilities of various plant species to act as bio-monitors for environmental uranium (U) contamination. Vegetation and soil samples were collected from a U processing facility. The water-way fed from facility storm and processing effluents was the focal sample site as it represented a primary U transport mechanism. Soils and sediments from areas exposed to contamination possessed U concentrations that averaged 630 mg U kg{sup -1}. Aquatic mosses proved to be exceptional accumulators of U with dry weight (dw) concentrations measuring as high as 12500 mg U kg{sup -1} (approximately 1% of the dw mass was attributable to U). The macrophytes (Phragmites communis, Scripus fontinalis and Sagittaria latifolia) were also effective accumulators of U. In general, plant roots possessed higher concentrations of U than associated upper portions of plants. For terrestrial plants, the roots of Impatiens capensis had the highest observed levels of U accumulation (1030 mg kg{sup -1}), followed by the roots of Cyperus esculentus and Solidago speciosa. The concentration ratio (CR) characterized dry weight (dw) vegetative U levels relative to that in associated dw soil. The plant species that accumulated U at levels in excess of that found in the soil were: P. communis root (CR, 17.4), I. capensis root (CR, 3.1) and S. fontinalis whole plant (CR, 1.4). Seven of the highest ten CR values were found in the roots. Correlations with concentrations of other metals with U were performed, which revealed that U concentrations in the plant were strongly correlated with nickel (Ni) concentrations (correlation: 0.992; r-squared: 0.984). Uranium in plant tissue was also strongly correlated with strontium (Sr) (correlation: 0.948; r-squared: 0.899). Strontium is chemically and physically similar to calcium (Ca) and magnesium (Mg), which were also positively-correlated with U. The correlation with U and these plant nutrient minerals, including iron (Fe), suggests that active

  3. Functional design criteria for the 242-A evaporator and PUREX (Plutonium-Uranium Extraction) Plant condensate interim retention basin

    SciTech Connect

    Cejka, C.C.

    1990-01-01

    This document contains the functional design criteria for a 26- million-gallon retention basin and 10 million gallons of temporary storage tanks. The basin and tanks will be used to store 242-A Evaporator process condensate, the Plutonium-Uranium Extraction (PUREX) Plant process distillate discharge stream, and the PUREX Plant ammonia scrubber distillate stream. Completion of the project will allow both the 242-A Evaporator and the PUREX Plant to restart. 4 refs.

  4. Natural phenomena hazards evaluation of equipment and piping of Gaseous Diffusion Plant Uranium Enrichment Facility

    SciTech Connect

    Singhal, M.K.; Kincaid, J.H.; Hammond, C.R.; Stockdale, B.I.; Walls, J.C.; Brock, W.R.; Denton, D.R.

    1995-12-31

    In support of the Gaseous Diffusion Plant Safety Analysis Report Upgrade program (GDP SARUP), a natural phenomena hazards evaluation was performed for the main process equipment and piping in the uranium enrichment buildings at Paducah and Portsmouth gaseous diffusion plants. In order to reduce the cost of rigorous analyses, the evaluation methodology utilized a graded approach based on an experience data base collected by SQUG/EPRI that contains information on the performance of industrial equipment and piping during past earthquakes. This method consisted of a screening walkthrough of the facility in combination with the use of engineering judgment and simple calculations. By using these screenings combined with evaluations that contain decreasing conservatism, reductions in the time and cost of the analyses were significant. A team of experienced seismic engineers who were trained in the use of the DOE SQUG/EPRI Walkdown Screening Material was essential to the success of this natural phenomena hazards evaluation.

  5. 16. VIEW OF THE ENRICHED URANIUM RECOVERY SYSTEM. ENRICHED URANIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. VIEW OF THE ENRICHED URANIUM RECOVERY SYSTEM. ENRICHED URANIUM RECOVERY PROCESSED RELATIVELY PURE MATERIALS AND SOLUTIONS AND SOLID RESIDUES WITH RELATIVELY LOW URANIUM CONTENT. URANIUM RECOVERY INVOLVED BOTH SLOW AND FAST PROCESSES. (4/4/66) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

  6. Literature review: Phytoaccumulation of chromium, uranium, and plutonium in plant systems

    SciTech Connect

    Hossner, L.R.; Loeppert, R.H.; Newton, R.J.; Szaniszlo, P.J.

    1998-05-01

    Phytoremediation is an integrated multidisciplinary approach to the cleanup of contaminated soils, which combines the disciplines of plant physiology, soil chemistry, and soil microbiology. Metal hyperaccumulator plants are attracting increasing attention because of their potential application in decontamination of metal-polluted soils. Traditional engineering technologies may be too expensive for the remediation of most sites. Removal of metals from these soils using accumulator plants is the goal of phytoremediation. The emphasis of this review has been placed on chromium (Cr), plutonium (Pu), and uranium (U). With the exception of Cr, these metals and their decay products exhibit two problems, specifically, radiation dose hazards and their chemical toxicity. The radiation hazard introduces the need for special precautions in reclamation beyond that associated with non-radioactive metals. The uptake of beneficial metals by plants occurs predominantly by way of channels, pores, and transporters in the root plasma membrane. Plants characteristically exhibit a remarkable capacity to absorb what they need and exclude what they don`t need. But most vascular plants absorb toxic and heavy metals through their roots to some extent, though to varying degrees, from negligible to substantial. Sometimes absorption occurs because of the chemical similarity between beneficial and toxic metals. Some plants utilize exclusion mechanisms, where there is a reduced uptake by the roots or a restricted transport of the metal from root to shoot. At the other extreme, hyperaccumulator plants absorb and concentrate metals in both roots and shoots. Some plant species endemic to metalliferous soils accumulate metals in percent concentrations in the leaf dry matter.

  7. Uranium hexafluoride packaging tiedown systems overview at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio. Revision 1

    SciTech Connect

    Becker, D.L.; Green, D.J.; Lindquist, M.R.

    1993-07-01

    The Portsmouth Gaseous Diffusion Plant (PORTS) in Piketon, Ohio, is operated by Martin Marietta Energy Systems, Inc., through the US Department of Energy-Oak Ridge Operations Office (DOE-ORO) for the US Department of Energy-Headquarters, Office of Nuclear Energy. The PORTS conducts those operations that are necessary for the production, packaging, and shipment of uranium hexafluoride (UF{sub 6}). Uranium hexafluoride enriched uranium than 1.0 wt percent {sup 235}U shall be packaged in accordance with the US Department of Transportation (DOT) regulations of Title 49 CFR Parts 173 (Reference 1) and 178 (Reference 2), or in US Nuclear Regulatory Commission (NRC) or US Department of Energy (DOE) certified package designs. Concerns have been expressed regarding the various tiedown methods and condition of the trailers being used by some shippers/carriers for international transport of the UF{sub 6} cylinders/overpacks. Because of the concerns about international shipments, the US Department of Energy-Headquarters (DOE-HQ) Office of Nuclear Energy, through DOE-HQ Transportation Management Division, requested Westinghouse Hanford Company (Westinghouse Hanford) to review UF{sub 6} packaging tiedown and shipping practices used by PORTS, and where possible and appropriate, provide recommendations for enhancing these practices. Consequently, a team of two individuals from Westinghouse Hanford visited PORTS on March 5 and 6, 1990, for the purpose of conducting this review. The paper provides a brief discussion of the review activities and a summary of the resulting findings and recommendations. A detailed reporting of the is documented in Reference 4.

  8. Assessment of enriched uranium storage safety issues at the Oak Ridge Y-12 Plant

    SciTech Connect

    1996-08-01

    This document is an assessment of the technical safety issues pertaining to the storage of EU at the Oak Ridge Y-12 Plant. The purpose of the assessment is to serve as the basis for defining the technical standards for storage of EU at Y-12. A formal assessment of the Y-12 materials acceptance criteria for EU is currently being conducted by a task force cochaired by B. G. Eddy of DOE Oak Ridge Operations and S. 0. Cox of Y-12 Defense Programs. The mission of this technical assessment for storage is obviously dependent on results of the acceptance assessment. Clearly, the two efforts require coordination to avoid inconsistencies. In addition, both these Assessments must be consistent with the Environmental Assessment for EU storage at Y-12.1 Both the Storage Assessment and the Criteria for Acceptance must take cognizance of the fact that a portion of the EU to be submitted for storage in the future is expected to be derived from foreign sources and to include previously irradiated uranium containing significant levels of transuranics, radioactive daughter products, and unstable uranium isotopes that do not occur in the EU stream of the DOE weapons complex. National security considerations may dictate that these materials be accepted despite the fact that they fail to conform to the Acceptance Criteria. This document will attempt to address the complexities inherent in this situation.

  9. Pilot uranium lysimeter studies at the Oak Ridge Y-12 plant

    SciTech Connect

    Francis, C.W.; Hyder, L.K.; Howard, S.C.; Cline, J.E.; Clapp, R.B.

    1993-08-01

    A field lysimeter test facility has been constructed at the Oak Ridge Y-12 plant to evaluate land burial of wastes containing depleted uranium. The principal objective in the construction of such a facility is to provide a means for monitoring waste leachate characteristics over time, in particular uranium concentrations in leachate. The design of the field lysimeter test facility allows, via the portals along the side walls of the lysimeter, the collection of leachate as a function of depth in the lysimeter. The methodology to collect leachate from within the field lysimeter has not been clearly defined. Thus, before wastes were loaded into the field lysimeter facility, a pilot lysimeter study was initiated to test several design concepts for the collection of in situ leachate. The primary objective of this pilot study was to demonstrate the feasibility and quality assurance of proposed instrumentation used to monitor leachate generation and characteristics in the full-scale field lysimeter. Secondary objectives included gaining experience in the handling/packing of wastes, installation/operation of the leachate collection devices, and waste leachate characterization

  10. Uranium fate in wetland mesocosms: Effects of plants at two iron loadings with different pH values

    EPA Science Inventory

    Small-scale continuous flow wetland mesocosms (~0.8 L) were used to evaluate how plant roots under different iron loadings affect uranium (U) mobility. When significant concentrations of ferrous iron (Fe) were present at circumneutral pH values, U concentrations in root exposed ...

  11. Uranium fate in wetland mesocosms: Effects of plants at two iron loadings with different pH values

    EPA Science Inventory

    Small-scale continuous flow wetland mesocosms (~0.8 L) were used to evaluate how plant roots under different iron loadings affect uranium (U) mobility. When significant concentrations of ferrous iron (Fe) were present at circumneutral pH values, U concentrations in root exposed ...

  12. Forage and rangeland plants from uranium mine soils: long-term hazard to herbivores and livestock?

    PubMed

    Gramss, Gerhard; Voigt, Klaus-Dieter

    2014-06-01

    Metalliferous uranium mine overburden soils integrated into arable land or stabilized by perennial rangeland plants evoke concern about the quality of crops and the exposure of grazing and thereby soil-ingesting (wildlife) herbivores to heavy metals (HM) and radionuclides. In a 2-year trial, thirteen annual and perennial forage and rangeland plants were thus potted on, or taken from, cultivated field soil of a metalliferous hot spot near Ronneburg (Germany). The content of soil and shoot tissues in 20 minerals was determined by ICP-MS to estimate HM (and uranium) toxicities to grazing animals and the plants themselves, and to calculate the long-term persistence of the metal toxicants (soil clean-up times) from the annual uptake rates of the plants. On Ronneburg soil elevated in As, Cd, Cu, Mn, Pb, U, and Zn, the shoot mineral content of all test plants remained preferentially in the range of "normal plant concentrations" but reached up to the fourfold to sixfold in Mn, Ni, and Zn, the 1.45- to 21.5-fold of the forage legislative limit in Cd, and the 10- to 180-fold of common herb concentrations in U. Shoot and the calculated root concentrations in Cd, Cu, Ni, and Zn accounted for phytotoxic effects at least to grasses and cereals. Based on WHO PTWI values for the tolerable weekly human Cd and Pb intake, the expanded Cd and Pb limits for forage, and reported rates of hay, roots, and adhering-soil ingestion, the tolerable daily intake rates of 0.65/11.6 mg in Cd/Pb by a 65 kg herbivore would be surpassed by the 11- to 27/0.7- to 4.7-fold across the year, with drastic consequences for winter-grazing and thereby high rates of roots and soil-ingesting animals. The daily intake of 5.3-31.5 mg of the alpha radiation emitter, U, may be less disastrous to short-lived herbivores. The annual phytoextraction rates of critical HM by the tested excluder crops indicate that hundreds to thousands of years are necessary to halve the HM and (long-lived) radionuclide load of

  13. Evaluation of terrestrial plants extracts for uranium sorption and characterization of potent phytoconstituents.

    PubMed

    Sharma, Sunita; Singh, Bikram; Thulasidas, S K; Kulkarni, Madhuri J; Natarajan, V; Manchanda, Vijay K

    2016-01-01

    Sorption capacity of four plants (Funaria hygrometrica, Musa acuminata, Brassica juncea and Helianthus annuus) extracts/fractions for uranium, a radionuclide was investigated by EDXRF and tracer studies. The maximum sorption capacity, i.e., 100% (complete sorption) was observed in case of Musa acuminata extract and fractions. Carbohydrate, proteins, phenolics and flavonoids contents in the active fraction (having maximum sorption capacity) were also determined. Further purification of the most active fraction provided three pure molecules, mannitol, sorbitol and oxo-linked potassium oxalate. The characterization of isolated molecules was achieved by using FTIR, NMR, GC-MS, MS-MS, and by single crystal-XRD analysis. Of three molecules, oxo-linked potassium oxalate was observed to have 100% sorption activity. Possible binding mechanism of active molecule with the uranyl cation has been purposed.

  14. Solubility classification of airborne uranium products collected at the perimeter of the Allied Chemical Plant, Metropolis, Illinois

    SciTech Connect

    Kalkwarf, D.R.

    1980-05-01

    Airborne uranium products were collected at the perimeter of the uranium-conversion plant operated by the Allied Chemical Corporation at Metropolis, Illinois, and the dissolution rates of these products were classified in terms of the ICRP Task Group Lung Model. Assignments were based on measurements of the dissolution half-times exhibited by uranium components of the dust samples as they dissolved in simulated lung fluid at 37/sup 0/C. Based on three trials, the dissolution behavior of dust with aerodynamic equivalent diameter (AED) less than 5.5 ..mu..m and collected nearest the closest residence to the plant was classified 0.40 D, 0.60 Y. Based on two trials, the dissolution behavior of dust with AED greater than 5.5 ..mu..m and collected at this location was classified 0.37 D, 0.63 Y. Based on one trial, the dissolution behavior of dust with AED less than 5.5 ..mu..m and collected at a location on the opposite side of the plant was classified 0.68 D, 0.32 Y. There was some evidence for adsorption of dissolved uranium onto other dust components during dissolution, and preliminary dissolution trials are recommended for future samples in order to optimize the fluid replacement schedule.

  15. Uranium aerosols at a nuclear fuel fabrication plant: Characterization using scanning electron microscopy and energy dispersive X-ray spectroscopy

    NASA Astrophysics Data System (ADS)

    Hansson, E.; Pettersson, H. B. L.; Fortin, C.; Eriksson, M.

    2017-05-01

    Detailed aerosol knowledge is essential in numerous applications, including risk assessment in nuclear industry. Cascade impactor sampling of uranium aerosols in the breathing zone of nuclear operators was carried out at a nuclear fuel fabrication plant. Collected aerosols were evaluated using scanning electron microscopy and energy dispersive X-ray spectroscopy. Imaging revealed remarkable variations in aerosol morphology at the different workshops, and a presence of very large particles (up to ≅ 100 × 50 μm2) in the operator breathing zone. Characteristic X-ray analysis showed varying uranium weight percentages of aerosols and, frequently, traces of nitrogen, fluorine and iron. The analysis method, in combination with cascade impactor sampling, can be a powerful tool for characterization of aerosols. The uranium aerosol source term for risk assessment in nuclear fuel fabrication appears to be highly complex.

  16. Mobile water treatment plant special study. Uranium Mill Tailings Remedial Action Project

    SciTech Connect

    Not Available

    1992-12-01

    Characterization of the level and extent of groundwater contamination in the vicinity of Title I mill sites began during the surface remedial action stage (Phase 1) of the Uranium Mill Tailings Remedial Action (UMTRA) Project. Some of the contamination in the aquifer(s) at the abandoned sites is attributable to milling activities during the years the mills were in operation. To begin implementation of Phase 11 groundwater remediation, the US Department of Energy (DOE) requested that (1) the Technical Assistance Contractor (TAC) conduct a study to provide for the design of a mobile water treatment plant to treat groundwater extracted during site characterization studies at completed Phase I UMTRA sites, and (2) the results of the TAC investigations be documented in a special study report. This special study develops the design criteria for a water treatment plant that can be readily transported from one UMTRA site to another and operated as a complete treatment system. The 1991 study provides the basis for selecting a mobile water treatment system to meet the operating requirements recommended in this special study. The scope of work includes the following: Determining contaminants, flows, and loadings. Setting effluent quality criteria. Sizing water treatment unit(s). Evaluating non-monetary aspects of alternate treatment processes. Comparing costs of alternate treatment processes. Recommending the mobile water treatment plant design criteria.

  17. Ecotoxicity evaluation of an amended soil contaminated with uranium and radium using sensitive plants

    NASA Astrophysics Data System (ADS)

    Abreu, M. M.; Lopes, J.; Magalhães, M. C. F.; Santos, E.

    2012-04-01

    In the centre-north granitic regions of Portugal, during the twenty century radium and uranium were exploited from approximately 60 mines. The closure of all uranium mines, in 2001, raised concerns regarding the possible chemical and radiological effects on the inhabitants health around the mine areas. The main objective of this work was to evaluate the effect of organic amendments and organic hydroxiapatite in the ecotoxicity reduction of agricultural soils contaminated with uranium and radium, by germination and growth tests of two sensitive plants (Lactuca sativa L. and Zea mays L.). Pot experiments, under controlled conditions, were undertaken during two months of incubation at 70% of the soil water-holding capacity. Fluvisol from Urgeiriça region containing large concentration of Utotal (635 mg/kg) and 226Ra (2310 Bq/kg) was used. The soil available fraction, extracted with ammonium acetate, corresponds to 90% and 25% of total concentration of Utotal and 226Ra, respectively. Fine ground bone (FB) and sheep manure (OM) single or mixtures were used as amendments. Four treatments, plus control were carried out in triplicate: (A) soil+40 Mg/ha of FB; (B) soil+70 Mg/ha of OM; (C) soil+70 Mg/ha of OM+40 Mg/ha of FB; (D) soil+70 Mg/ha of OM+20 Mg/ha of FB. After the incubation moist soils were kept at 4-5 °C and subsamples were used for leachates extraction following DIN 38414-S4 method. Maize and lettuce seeds were sown in filter paper moistened with the leachates aqueous solutions and in the moist soil for germination and growth tests. Seedlings after three days of germination were used for growth tests in hydroponic, during seven days, using the leachates. Five seeds per replicate were used. Soil presented: pH(H2O)=5.15, EC=7.3 µS/cm; and Corgnic=12.5 g/kg. After two months of incubation soil pH increased to a maximum of 6.53 in amended samples, and EC showed a dramatic increase when compared to the control (0.398 dS/m), from 1.5 dS/m (treatment-A) to 4.7 d

  18. Uranium hexafluoride packaging tiedown systems overview at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    SciTech Connect

    Becker, D.L.; Lindquist, M.R.

    1993-03-01

    The Portsmouth Gaseous Diffusion Plant (PORTS) in Piketon, Ohio operated by Martin Marietta Energy Systems, Inc., through the US Department of Energy-Oak Ridge Operations Office (DOE-ORO) for the US Department of Energy Headquarters, Office of Nuclear Energy. The PORTS conducts those operations that are necessary for the production, packaging, and shipment of enriched uranium hexafluoride (UF{sub 6}). Uranium hexafluoride enriched greater than 1.0 wt percent {sup 235}U shall be packaged in accordance with the US Department of Transportation (DOT) regulations of Title 49 CFR Parts 173 (Reference 1) and 178 (Reference 2), or in US Nuclear Regulatory Commission (NRC) or US Department of Energy (DOE) certified package designs. Concerns have been expressed regarding the various tiedown methods and condition of the trailers being used by some shippers/carriers for international transport of the UF{sub 6} cylinders/overpacks (Reference 3). Because of the concerns about international shipments, the US Department of Energy-Headquarters (DOE-HQ) Office of Nuclear Energy, through DOE-HQ Transportation Management Division, requested Westinghouse Hanford Company (Westinghouse Hanford) to review UF{sub 6} packaging tiedown and shipping practices used by PORTS, and where possible and appropriate, provide recommendations for enhancing these practices. Consequently, a tram of two individuals from Westinghouse Hanford visited PORTS on March 5 and 6, 1990, for the purpose of conducting this review. The paper provides a brief discussion of the review activities and a summary of the resulting findings and recommendations. A detailed reporting of the review is documented in Reference 4.

  19. RADIO FREQUENCY IDENTIFICATION DEVICES: EFFECTIVENESS IN IMPROVING SAFEGUARDS AT GAS-CENTRIFUGE URANIUM-ENRICHMENT PLANTS.

    SciTech Connect

    JOE,J.

    2007-07-08

    Recent advances in radio frequency identification devices (RFIDs) have engendered a growing interest among international safeguards experts. Potentially, RFIDs could reduce inspection work, viz. the number of inspections, number of samples, and duration of the visits, and thus improve the efficiency and effectiveness of international safeguards. This study systematically examined the applications of RFIDs for IAEA safeguards at large gas-centrifuge enrichment plants (GCEPs). These analyses are expected to help identify the requirements and desirable properties for RFIDs, to provide insights into which vulnerabilities matter most, and help formulate the required assurance tests. This work, specifically assesses the application of RFIDs for the ''Option 4'' safeguards approach, proposed by Bruce Moran, U. S. Nuclear Regulatory Commission (NRC), for large gas-centrifuge uranium-enrichment plants. The features of ''Option 4'' safeguards include placing RFIDs on all feed, product and tails (F/P/T) cylinders, along with WID readers in all FP/T stations and accountability scales. Other features of Moran's ''Option 4'' are Mailbox declarations, monitoring of load-cell-based weighing systems at the F/P/T stations and accountability scales, and continuous enrichment monitors. Relevant diversion paths were explored to evaluate how RFIDs improve the efficiency and effectiveness of safeguards. Additionally, the analysis addresses the use of RFIDs in conjunction with video monitoring and neutron detectors in a perimeter-monitoring approach to show that RFIDs can help to detect unidentified cylinders.

  20. Realities of verifying the absence of highly enriched uranium (HEU) in gas centrifuge enrichment plants

    SciTech Connect

    Swindle, D.W.

    1990-03-01

    Over a two and one-half year period beginning in 1981, representatives of six countries (United States, United Kingdom, Federal Republic of Germany, Australia, The Netherlands, and Japan) and the inspectorate organizations of the International Atomic Energy Agency and EURATOM developed and agreed to a technically sound approach for verifying the absence of highly enriched uranium (HEU) in gas centrifuge enrichment plants. This effort, known as the Hexapartite Safeguards Project (HSP), led to the first international concensus on techniques and requirements for effective verification of the absence of weapons-grade nuclear materials production. Since that agreement, research and development has continued on the radiation detection technology-based technique that technically confirms the HSP goal is achievable. However, the realities of achieving the HSP goal of effective technical verification have not yet been fully attained. Issues such as design and operating conditions unique to each gas centrifuge plant, concern about the potential for sensitive technology disclosures, and on-site support requirements have hindered full implementation and operator support of the HSP agreement. In future arms control treaties that may limit or monitor fissile material production, the negotiators must recognize and account for the realities and practicalities in verifying the absence of HEU production. This paper will describe the experiences and realities of trying to achieve the goal of developing and implementing an effective approach for verifying the absence of HEU production. 3 figs.

  1. About the assumption of linearity in soil-to-plant transfer factors for uranium and thorium isotopes and 226Ra.

    PubMed

    Blanco, Rodríguez P; Vera, Tomé F; Lozano, J C

    2002-02-04

    The linearity assumption for soil and plant concentrations of radionuclides is usually a good approximation for use in food-chain models. To verify this assumption, different samples of plant and substrate were collected from a granitic zone located near a disused uranium mine in order to cover a large range of concentrations. In all of the samples, the activity concentration of 226Ra and of different isotopes of uranium (238U and 234U) and thorium (232Th, 230Th and 228Th) were determined. The results indicate that the linearity assumption can be considered valid when the range of concentrations taken into account is large (approx. two orders of magnitude). Otherwise, there is a clear deviation from linearity. Also, the influence of different stable elements on the soil-plant transfer factors was studied by using multivariate regression methods. The uptake of uranium, thorium and radium was found to be mainly associated with the concentration of iron in the plant and the phosphorus and alkaline earths in the substrate.

  2. Technology, Safety and Costs of Decommissioning a Reference Uranium Hexafluoride Conversion Plant

    SciTech Connect

    Elder, H. K.

    1981-10-01

    Safety and cost information is developed for the conceptual decommissioning of a commercial uranium hexafluoride conversion (UF{sub 6}) plant. Two basic decommissioning alternatives are studied to obtain comparisons between cost and safety impacts: DECON, and passive SAFSTOR. A third alternative, DECON of the plant and equipment with stabilization and long-term care of lagoon wastes. is also examined. DECON includes the immediate removal (following plant shutdown) of all radioactivity in excess of unrestricted release levels, with subsequent release of the site for public use. Passive SAFSTOR requires decontamination, preparation, maintenance, and surveillance for a period of time after shutdown, followed by deferred decontamination and unrestricted release. DECON with stabilization and long-term care of lagoon wastes (process wastes generated at the reference plant and stored onsite during plant operation} is also considered as a decommissioning method, although its acceptability has not yet been determined by the NRC. The decommissioning methods assumed for use in each decommissioning alternative are based on state-of-the-art technology. The elapsed time following plant shutdown required to perform the decommissioning work in each alternative is estimated to be: for DECON, 8 months; for passive SAFSTOR, 3 months to prepare the plant for safe storage and 8 months to accomplish deferred decontamination. Planning and preparation for decommissioning prior to plant shutdown is estimated to require about 6 months for either DECON or passive SAFSTOR. Planning and preparation prior to starting deferred decontamination is estimated to require an additional 6 months. OECON with lagoon waste stabilization is estimated to take 6 months for planning and about 8 months to perform the decommissioning work. Decommissioning cost, in 1981 dollars, is estimated to be $5.91 million for OECON. For passive SAFSTOR, preparing the facility for safe storage is estimated to cost $0

  3. Derivation of residual radioactive material guidelines for uranium in soil at the Middlesex Sampling Plant Site, Middlesex, New Jersey

    SciTech Connect

    Dunning, D.E.

    1995-02-01

    Residual radioactive material guidelines for uranium in soil were derived for the Middlesex Sampling Plant (MSP) site in Middlesex, New Jersey. This site has been designated for remedial action under the Formerly Utilized Sites Remedial Action Program (FUSRAP) of the US Department of Energy. The site became contaminated from operations conducted in support of the Manhattan Engineer District (MED) and the Atomic Energy Commission (AEC) between 1943 and 1967. Activities conducted at the site included sampling, storage, and shipment of uranium, thorium, and beryllium ores and residues. Uranium guidelines for single radioisotopes and total uranium were derived on the basis of the requirement that the 50-year committed effective dose equivalent to a hypothetical individual living or working in the immediate vicinity of the MSP site should not exceed a dose of 30 mrem/yr following remedial action for the current-use and likely future-use scenarios or a dose of 100 mrem/yr for less likely future-use scenarios. The RESRAD computer code, which implements the methodology described in the DOE manual for establishing residual radioactive material guidelines, was used in this evaluation. Four scenarios were considered for the site. These scenarios vary regarding future land use at the site, sources of water used, and sources of food consumed.

  4. Recycling Of Uranium- And Plutonium-Contaminated Metals From Decommissioning Of The Hanau Fuel Fabrication Plant

    SciTech Connect

    Kluth, T.; Quade, U.; Lederbrink, F. W.

    2003-02-26

    Decommissioning of a nuclear facility comprises not only actual dismantling but also, above all, management of the resulting residual materials and waste. Siemens Decommissioning Projects (DP) in Hanau has been involved in this task since 1995 when the decision was taken to decommission and dismantle the Hanau Fuel Fabrication Plant. Due to the decommissioning, large amounts of contaminated steel scrap have to be managed. The contamination of this metal scrap can be found almost exclusively in the form of surface contamination. Various decontamination technologies are involved, as there are blasting and wiping. Often these methods are not sufficient to meet the free release limits. In these cases, SIEMENS has decided to melt the scrap at Siempelkamp's melting plant. The plant is licensed according to the German Radiation Protection Ordinance Section 7 (issue of 20.07.2001). The furnace is a medium frequency induction type with a load capacity of 3.2 t and a throughput of 2 t/h for steel melting. For safety reasons, the furnace is widely operated by remote handling. A highly efficient filter system of cyclone, bag filter and HEPA-filter in two lines retains the dust and aerosol activity from the off-gas system. The slag is solidified at the surface of the melt and gripped before pouring the liquid iron into a chill. Since 1989, in total 15,000 t have been molten in the plant, 2,000 t of them having been contaminated steel scrap from the decommissioning of fuel fabrication plants. Decontamination factors could be achieved between 80 and 100 by the high affinity of the uranium to the slag former. The activity is transferred to the slag up to nearly 100 %. Samples taken from metal, slag and dust are analyzed by gamma measurements of the 186 keV line of U235 and the 1001 keV line of Pa234m for U238. All produced ingots showed a remaining activity less than 1 Bq/g and could be released for industrial reuse.

  5. Atmospheric dispersion of radon around uranium mill tailings of the former Pridneprovsky Chemical Plant in Ukraine.

    PubMed

    Kovalets, Ivan V; Asker, Christian; Khalchenkov, Alexander V; Persson, Christer; Lavrova, Tatyana V

    2017-06-01

    Simulations of atmospheric dispersion of radon around the uranium mill tailings of the former Pridneprovsky Chemical Plant (PChP) in Ukraine were carried out with the aid of two atmospheric dispersion models: the Airviro Grid Model and the CALMET/CALPUFF model chain. The available measurement data of radon emission rates taken in the territories and the close vicinity of tailings were used in simulations. The results of simulations were compared to the yearly averaged measurements of concentration data. Both models were able to reasonably reproduce average radon concentration at the Sukhachivske site using averaged measured emission rates as input together with the measured meteorological data. At the same time, both models significantly underestimated concentrations as compared to measurements collected at the PChP industrial site. According to the results of both dispersion models, it was shown that only addition of significant radon emission rate from the whole territory of PChP in addition to emission rates from the tailings could explain the observed concentration measurements. With the aid of the uncertainty analysis, the radon emission rate from the whole territory of PChP was estimated to be between 1.5 and 3.5 Bq·m(-2)s(-1). Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Safeguards Guidance for Designers of Commercial Nuclear Facilities – International Safeguards Requirements for Uranium Enrichment Plants

    SciTech Connect

    Philip Casey Durst; Scott DeMuth; Brent McGinnis; Michael Whitaker; James Morgan

    2010-04-01

    For the past two years, the United States National Nuclear Security Administration, Office of International Regimes and Agreements (NA-243), has sponsored the Safeguards-by-Design Project, through which it is hoped new nuclear facilities will be designed and constructed worldwide more amenable to nuclear safeguards. In the course of this project it was recognized that commercial designer/builders of nuclear facilities are not always aware of, or understand, the relevant domestic and international safeguards requirements, especially the latter as implemented by the International Atomic Energy Agency (IAEA). To help commercial designer/builders better understand these requirements, a report was prepared by the Safeguards-by-Design Project Team that articulated and interpreted the international nuclear safeguards requirements for the initial case of uranium enrichment plants. The following paper summarizes the subject report, the specific requirements, where they originate, and the implications for design and construction. It also briefly summarizes the established best design and operating practices that designer/builder/operators have implemented for currently meeting these requirements. In preparing the subject report, it is recognized that the best practices are continually evolving as the designer/builder/operators and IAEA consider even more effective and efficient means for meeting the safeguards requirements and objectives.

  7. Laboratory demonstration of a multi-sensor unattended cylinder verification station for uranium enrichment plant safeguards

    SciTech Connect

    Goodman, David I; Rowland, Kelly L; Smith, Sheriden; Miller, Karen A.; Flynn, Eric B.

    2014-01-10

    The objective of safeguards is the timely detection of the diversion of a significant quantity of nuclear materials, and safeguarding uranium enrichment plants is especially important in preventing the spread of nuclear weapons. The IAEA’s proposed Unattended Cylinder Verification Station (UCVS) for UF6 cylinder verification would combine the operator’s accountancy scale with a nondestructive assay system such as the Passive Neutron Enrichment Meter (PNEM) and cylinder identification and surveillance systems. In this project, we built a laboratory-scale UCVS and demonstrated its capabilities using mock UF6 cylinders. We developed a signal processing algorithm to automate the data collection and processing from four continuous, unattended sensors. The laboratory demonstration of the system showed that the software could successfully identify cylinders, snip sensor data at the appropriate points in time, determine the relevant characteristics of the cylinder contents, check for consistency among sensors, and output the cylinder data to a file. This paper describes the equipment, algorithm and software development, laboratory demonstration, and recommendations for a full-scale UCVS.

  8. Gamma-ray imaging as a tool for uranium processing plants

    SciTech Connect

    Ziock, K.P.; Madison, L.; McGinnis, B.R.

    1995-08-03

    Gamma-radiation is frequently used as an analysis and characterization signal to monitor material in the nuclear fuel processing cycle. The selection as a diagnostic is self-evident since the radiation is ubiquitous, characteristic of the isotopes present, and sufficiently penetrating so that measurements may be made remotely. However, save through detector proximity or minimal collimation, the directional nature of the radiation is generally not used in traditional nondestructive assay (NDA) measurements. To demonstrate the additional information available, we used GRIS, the Gamma-Ray Imaging Spectrometer, at the K-25 and Portsmouth gaseous diffusion plants. In this facility, UF{sub 6} gas is enriched in heated equipment and piping which run inside an insulated housing. Occasionally, the process develops uranium deposits due to leakage of wet air or environmental changes within the housing that cause solidification of the process gas. When such deposits occur, traditional NDA techniques frequently require costly and time-consuming entry within the heat shielding to obtain precise information on the deposit unavailable from outside the shielding. In this paper we discuss GRIS, the gamma-ray imaging technique it uses, and present the results of measurements obtained on fuel processing equipment.

  9. US-Russian collaboration in MPC & A enhancements at the Elektrostal Uranium Fuel-Fabrication Plant

    SciTech Connect

    Smith, H.; Murray, W.; Whiteson, R.

    1997-11-01

    Enhancement of the nuclear materials protection, control, and accounting of (MPC&A) at the Elektrostal Machine-Building Plant (ELEMASH) has proceeded in two phases. Initially, Elektrostal served as the model facility at which to test US/Russian collaboration and to demonstrate MPC&A technologies available for safeguards enhancements at Russian facilities. This phase addressed material control and accounting (MC&A) in the low-enriched uranium (LEU) fuel-fabrication processes and the physical protection (PP) of part of the (higher-enrichment) breeder-fuel process. The second phase, identified later in the broader US/Russian agreement for expanded MPC&A cooperation. includes implementation of appropriate MC&A and PP systems in the breeder-fuel fabrication processes. Within the past year, an automated physical protection system has been installed and demonstrated in building 274, and an automated MC&A system has been designed and is being installed and will be tested in the LEU process. Attention has now turned to assuring longterm sustainability for the first phase and beginning MPC&A upgrades for the second phase. Sustainability measures establish the infrastructure for operation, maintenance, and repair of the installed systems-with US support for the lifetime of the US/Russian Agreement, but evolving toward full Russian operation of the system over the long term. For phase 2, which will address higher enrichments, projects have been identified to characterize the facilities, design MPC&A systems, procure appropriate equipment, and install and test final systems. One goal in phase 2 will be to build on initial work to create shared, plant-wide MPC&A assets for operation, maintenance, and evaluation of all safeguards systems.

  10. Nuclear criticality safety controls for uranium deposits during D and D at the Oak Ridge Gaseous Diffusion Plant

    SciTech Connect

    Haire, M.J.; Jordan, W.C.; Jollay, L.J. III; Dahl, T.L.

    1997-02-01

    The US Department of Energy (DOE) Deputy Assistant Secretary of Energy for Environmental Management has issued a challenge to complete DOE environmental cleanup within a decade. The response for Oak Ridge facilities is in accordance with the DOE ten-year plan which calls for completion of > 95% of environmental management work by the year 2006. This will result in a 99% risk reduction and in a significant savings in base line costs in waste management (legacy waste); remedial action (groundwater, soil, etc.); and decontamination and decommissioning (D and D). It is assumed that there will be long-term institutional control of cascade equipment, i.e., there will be no walk away from sites, and that there will be firm radioactivity release limits by 1999 for recycle metals. An integral part of these plants is the removal of uranium deposits which pose nuclear criticality safety concerns in the shut down of the Oak Ridge Gaseous Diffusion Plant. DOE has initiated the Nuclear Criticality Stabilization Program to improve nuclear criticality safety by removing the larger uranium deposits from unfavorable geometry equipment. Nondestructive assay (NDA) measurements have identified the location of these deposits. The objective of the K-25 Site Nuclear Criticality Stabilization Program is to remove and place uranium deposits into safe geometry storage containers to meet the double contingency principle. Each step of the removal process results in safer conditions where multiple controls are present. Upon completion of the Program, nuclear criticality risks will be greatly reduced.

  11. Genus identification of toxic plant by real-time PCR.

    PubMed

    Matsuyama, Shuji; Nishi, Katsuji

    2011-03-01

    Some plants have toxicities that are dangerous for humans. In the case of poisoning by toxic plants, a rapid and easy screening test is required for accurate medical treatment or forensic investigation. In this study, we designed specific primer pairs for identification of toxic plants, such as subgenus Aconitum, genus Ricinus, genus Illicium, and genus Scopolia, by internal transcribed spacer sequences of nuclear ribosomal DNA. Allied species of target plants, foods, and human DNA were not detected, but each primer pair provided a specific PCR product from the target plant using real-time PCR. This method can detect the subgenus Aconitum, genus Ricinus, and genus Scopolia with template DNA of 10 pg, respectively, and genus Illicium with 1 pg. Furthermore, each primer pair provided the exact PCR product from digested target plants in artificial gastric fluid. When a trace unknown plant sample in forensic investigation is collected from stomach contents, this PCR assay may be useful for screening toxic plants.

  12. [The assessment of no adverse effect doses for plant populations chronically exposed to radionuclides of uranium and thorium decay series].

    PubMed

    Evseeva, T I; Maĭstrenko, T A; Belykh, E S; Geras'kin, S A

    2010-01-01

    Dose rates cause no adverse effects on natural populations of Pinus sylvestris L. and Vicia cracca L. inhabiting territories contaminated by uranium mill tailings and radium production wastes (Vodny settlement, Komi Republic) were determined. A significant increase in embryonic lethal mutation frequency in V. cracca legumes and decrease in seedlings survival rate as compared with control values were registered at dose rate equal to 1.67 mGy/day, that is 280 times higher than the one calculated for the reference site. The adverse effects in P. sylvestris expressed in increased frequency of chromosome aberrations in meristematic root tips and decreased reproductive capacity of seeds were determined at absorbed dose rate equal to 0.083 mGy/day. Data obtained show that the decrease in plant reproductive capacity in case of chronic exposure of radionuclides of uranium and thorium decay series can observe at lower weighted absorbed dose rates than in case of environmental contamination by artificial radionuclides.

  13. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Paducah Gaseous Diffusion Plant site

    SciTech Connect

    Marmer, G.J.; Dunn, C.P.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Yuen, C.R.; Cleland, J.H.

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. The U-235 atoms are ionized when precisely tuned laser light -- of appropriate power, spectral, and temporal characteristics -- illuminates the uranium vapor and selectively photoionizes the U-235 isotope. A programmatic document for use in screening DOE site to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the PGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. 65 refs., 15 tabs.

  14. Real-time X-ray absorption spectroscopy of uranium, iron, and manganese in contaminated sediments during bioreduction.

    PubMed

    Tokunag, Tetsu K; Wan, Jiamin; Kim, Yongman; Sutton, Steve R; Newville, Matthew; Lanzirotti, Antonio; Rao, William

    2008-04-15

    The oxidation status of uranium in sediments is important because the solubility of this toxic and radioactive element is much greater for U(VI) than for U(IV) species. Thus, redox manipulation to promote precipitation of UO2 is receiving interest as a method to remediate U-contaminated sediments. Presence of Fe and Mn oxides in sediments at much higher concentrations than U requires an understanding of their redox status as well. This study was conducted to determine changes in oxidation states of U, Fe, and Mn in U-contaminated sediments from Oak Ridge National Laboratory. Oxidation states of these elements were measured in real-time and nondestructively using X-ray absorption spectroscopy on sediment columns supplied with synthetic groundwater containing organic carbon (OC, 0, 3, 10, 30, and 100 mM OC as lactate) for over 400 days. In sediments supplied with OC > or = 30 mM, 80% of the U was reduced to U(IV), with transient reoxidation at about 150 days. Mn(III,IV) oxides were completely reduced to Mn(II) in sediments infused with OC > or = 3 mM. However, Fe remained largely unreduced in all sediment columns, showing that Fe(III) can persist as an electron acceptor in reducing sediments over long times. This result in combination with the complete reduction of all other potential electron acceptors supports the hypothesis that the reactive Fe(III) fraction was responsible for reoxidizing U(IV).

  15. Real-time x-ray absorption spectroscopy of uranium, iron, and manganese in contaminated sediments during bioreduction

    SciTech Connect

    Tokunaga, Tetsu; Tokunaga, T.K.; Wan, J.; Kim, Y.; Sutton, S.R.; Newville, M.; Lanzirotti, A.; Rao, W.

    2008-01-15

    The oxidation status of uranium in sediments is important because the solubility of this toxic and radioactive element is much greater for U(VI) than for U(IV) species. Thus, redox manipulation to promote precipitation of UO{sub 2} is receiving interest as a method to remediate U-contaminated sediments. Presence of Fe and Mn oxides in sediments at much higher concentrations than U requires understanding of their redox status as well. This study was conducted to determine changes in oxidation states of U, Fe, and Mn in U-contaminated sediments from Oak Ridge National Laboratory. Oxidation states of these elements were measured in real-time and nondestructively using X-ray absorption spectroscopy, on sediment columns supplied with synthetic groundwater containing organic carbon (OC, 0, 3, 10, 30 and 100 mM OC as lactate) for over 400 days. In sediments supplied with OC {ge} 30 mM, 80% of the U was reduced to U(IV), with transient reoxidation at about 150 days. Mn(III,IV) oxides were completely reduced to Mn(II) in sediments infused with OC {ge} 3 mM. However, Fe remained largely unreduced in all sediment columns, showing that Fe(III) can persist as an electron acceptor in reducing sediments over long times. This result in combination with the complete reduction of all other potential electron acceptors supports the hypothesis that the reactive Fe(III) fraction was responsible for reoxidizing U(IV).

  16. Feasibility Study on the Use of On-line Multivariate Statistical Process Control for Safeguards Applications in Natural Uranium Conversion Plants

    SciTech Connect

    Ladd-Lively, Jennifer L

    2014-01-01

    The objective of this work was to determine the feasibility of using on-line multivariate statistical process control (MSPC) for safeguards applications in natural uranium conversion plants. Multivariate statistical process control is commonly used throughout industry for the detection of faults. For safeguards applications in uranium conversion plants, faults could include the diversion of intermediate products such as uranium dioxide, uranium tetrafluoride, and uranium hexafluoride. This study was limited to a 100 metric ton of uranium (MTU) per year natural uranium conversion plant (NUCP) using the wet solvent extraction method for the purification of uranium ore concentrate. A key component in the multivariate statistical methodology is the Principal Component Analysis (PCA) approach for the analysis of data, development of the base case model, and evaluation of future operations. The PCA approach was implemented through the use of singular value decomposition of the data matrix where the data matrix represents normal operation of the plant. Component mole balances were used to model each of the process units in the NUCP. However, this approach could be applied to any data set. The monitoring framework developed in this research could be used to determine whether or not a diversion of material has occurred at an NUCP as part of an International Atomic Energy Agency (IAEA) safeguards system. This approach can be used to identify the key monitoring locations, as well as locations where monitoring is unimportant. Detection limits at the key monitoring locations can also be established using this technique. Several faulty scenarios were developed to test the monitoring framework after the base case or normal operating conditions of the PCA model were established. In all of the scenarios, the monitoring framework was able to detect the fault. Overall this study was successful at meeting the stated objective.

  17. Assessment of magnetic field exposures for a mortality study at a uranium enrichment plant.

    PubMed

    Wenzl, T B

    1999-01-01

    A survey of workplace exposures to 60-Hz magnetic fields was carried out at a large uranium enrichment facility to assign exposures for an updated mortality study. Stratified random selection was used to choose workers for measurement in all jobs and areas, to determine whether consistent distinctions could be made between job groups based on average magnetic field exposures. A total of 252 workdays was measured with a personal monitor, and individual average magnetic field exposures ranged from 0.20 to 82.6 mG. A priori job groups showed significant differences between geometric mean exposures, which ranged from 0.80 to 3.51 mG. Most of these groups showed widely ranging exposures, so they were subdivided based on location and job title to improve the precision of the exposure assignments for the mortality study. These final assignments were made up of 26 groups having arithmetic means ranging from 0.43 to 24.9 mG, with most groups defined by location in addition to job title. In general, electrical maintenance workers did not have elevated magnetic field exposures (> 3 mG), but the exposures of the electricians in switchyard (substation) jobs were elevated. Available employment records did not allow most electricians to be distinguished based on location, so they were assigned exposures based on their plantwide average (above 7 mG). An estimated 9% of the work time of this cohort was spent at daily average exposures above 3 mG, despite the very large electric power consumption at this plant.

  18. Signatures and Methods for the Automated Nondestructive Assay of UF6 Cylinders at Uranium Enrichment Plants

    SciTech Connect

    Smith, Leon E.; Mace, Emily K.; Misner, Alex C.; Shaver, Mark W.

    2010-08-08

    International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders taken to be representative of the facility’s entire cylinder inventory. These measurements are time-consuming, expensive, and assay only a small fraction of the total cylinder volume. An automated nondestructive assay system capable of providing enrichment measurements over the full volume of the cylinder could improve upon current verification practices in terms of manpower and assay accuracy. Such a station would use sensors that can be operated in an unattended mode at an industrial facility: medium-resolution scintillators for gamma-ray spectroscopy (e.g., NaI(Tl)) and moderated He-3 neutron detectors. This sensor combination allows the exploitation of additional, more-penetrating signatures beyond the traditional 185-keV emission from U-235: neutrons produced from F-19(α,n) reactions (spawned primarily from U 234 alpha emission) and high-energy gamma rays (extending up to 8 MeV) induced by neutrons interacting in the steel cylinder. This paper describes a study of these non-traditional signatures for the purposes of cylinder enrichment verification. The signatures and the radiation sensors designed to collect them are described, as are proof-of-principle cylinder measurements and analyses. Key sources of systematic uncertainty in the non-traditional signatures are discussed, and the potential benefits of utilizing these non-traditional signatures, in concert with an automated form of the traditional 185-keV-based assay, are discussed.

  19. Evaluation of Foreign Investment in Power Plants using Real Options

    NASA Astrophysics Data System (ADS)

    Kato, Moritoshi; Zhou, Yicheng

    This paper proposes new methods for evaluating foreign investment in power plants under market uncertainty using a real options approach. We suppose a thermal power plant project in a deregulated electricity market. One of our proposed methods is that we calculate the cash flow generated by the project in a reference year using actual market data to incorporate periodic characteristics of energy prices into a yearly cash flow model. We make the stochastic yearly cash flow model with the initial value which is the cash flow in the reference year, and certain trend and volatility. Then we calculate the real options value (ROV) of the project which has abandonment options using the yearly cash flow model. Another our proposed method is that we evaluate foreign currency/domestic currency exchange rate risk by representing ROV in foreign currency as yearly pay off and exchanging it to ROV in domestic currency using a stochastic exchange rate model. We analyze the effect of the heat rate and operation and maintenance costs of the power plant on ROV, and evaluate exchange rate risk through numerical examples. Our proposed method will be useful for the risk management of foreign investment in power plants.

  20. Solubility classification of airborne uranium products collected at the perimeter of the Allied Chemical Plant, Metropolis, Illinois

    SciTech Connect

    Kalkwarf, D.R.

    1980-06-01

    The purpose of this study was to collect airborne uranium products at the perimeter of the uranium-conversion plant operated by the Allied Chemical Corporation at Metropolis, Illinois, and to classify the dissolution rates of these products in terms of the ICRP Task Group Lung Model. The International Commission on Radiological Protection developed this model for use in computing the radiation dose from radionuclides deposited in the lung. A key parameter is the classification of the deposited material according to the rate at which it leaves the lung. Three classes were established: D, W, and Y, corresponding to half-times in the lung of 0 to 10 days, 11 to 100 days, and > 100 days, respectively. If clearance of the material from the lung is not strictly exponential with time, it is approximated by a sum of exponentials; and the material is classified according to the fractions of D, W, and Y components. Assignments were based on measurements of the dissolution half-times exhibited by uranium components of the dust samples as they dissolved in simulated lung fluid at 37C. Although endocytosis and ciliary-mucus transport are known to contribute to lung clearance, experiments have indicated that a few days after dust deposition, dissolution determines the clearance rate for the lower respiratory tract.

  1. Nondestructive and Real-time Measurement of Moisture in Plant

    NASA Astrophysics Data System (ADS)

    Ogawa, Yuichi; Kawase, Kodo; Mizuno, Maya; Yamashita, Masatsugu; Otani, Chiko

    We constructed a THz transillumination system for water content monitoring, and we succeeded in measuring the moisture level in plants. Our measurement system uses a widely tunable coherent THz parametric oscillator source. As target we chose for this experiment a leaf of Japanese basil. The time variation of the water content in the leaf was monitored in two situations: a leaf freshly cut which is left to dry out, and the leaf of a water stressed plant. We found by real-time measurements that the water content of a cut leaf does not decrease uniformly in time. Also, the response to water stress is delayed by about 5-10 minutes. Furthermore, we demonstrated a moisture measurement using a transillumination THz imaging system. As target we chose for this experiment a leaf of Hedera helix held between two thin plastic sheets. The change of the moisture distribution is clearly visible. These results show that the method described here can be applied to nondestructive and real-time monitoring of water content in plants.

  2. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Portsmouth Gaseous Diffusion Plant site

    SciTech Connect

    Marmer, G.J.; Dunn, C.P.; Filley, T.H.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Cleland, J.H.

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. In the 1970s, the US Department of Energy (DOE) began investigating more efficient and cost-effective enrichment technologies. In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser isotope Separation (U-AVLIS) technology with the near-term goal to provide the necessary information to make a deployment decision by November 1992. Initial facility operation is anticipated for 1999. A programmatic document for use in screening DOE sites to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. The final evaluation, which included sensitivity studies, identified the Oak Ridge Gaseous Diffusion Plant (ORGDP) site, the Paducah Gaseous Diffusion Plant (PGDP) site, and the Portsmouth Gaseous Diffusion Plant (PORTS) site as having significant advantages over the other sites considered. This environmental site description (ESD) provides a detailed description of the PORTS site and vicinity suitable for use in an environmental impact statement (EIS). This report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during site visits. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use. Socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3.

  3. Bioaccumulation of 226Ra by plants growing in fresh water ecosystem around the uranium industry at Jaduguda, India.

    PubMed

    Jha, V N; Tripathi, R M; Sethy, N K; Sahoo, S K; Shukla, A K; Puranik, V D

    2010-09-01

    A field study has been conducted to evaluate the (226)Ra bioaccumulation among aquatic plants growing in the stream/river adjoining the uranium mining and ore-processing complex at Jaduguda, India. Two types of plant group have been investigated namely free floating algal species submerged into water and plants rooted in stream & riverbed. The highest (226)Ra activity concentration (9850 Bq kg(-1)) was found in filamentous algae growing in the residual water of tailings pond. The concentration ratios of (226)Ra in filamentous algae (activity concentration of (226)Ra in plant Bq kg(-1) fresh weight/activity concentration of (226)Ra in water Bq l(-1)) widely varied i.e. from 1.1 x 10(3) to 8.6 x 10(4). Other aquatic plants were also showing wide variability in the (226)Ra activity concentration. The ln-transformed filamentous algae (226)Ra activity concentration was significantly correlated with that of ln-transformed water concentration (r = 0.89, p < 0.001). There was no correlation between the activity concentrations of (226)Ra in stream/riverbed rooted plants and the substrate. For this group, correlation between (226)Ra activity concentration and Mn, Fe, Cu concentration in plants were statistically significant.

  4. An assessment of plant biointrusion at the Uranium Mill Tailings Remedial Action Project rock-covered disposal cells

    SciTech Connect

    Not Available

    1990-10-01

    This study is one of a number of special studies that have been conducted regarding various aspects of the Uranium Mill Tailings Remedial Action (UMTRA) Project. This special study was proposed following routine surveillance and maintenance surveys and observations reported in a special study of vegetative covers (DOE, 1988), in which plants were observed growing up through the rock erosion layer at recently completed disposal cells. Some of the plants observed were deep-rooted woody species, and questions concerning root intrusion into disposal cells and the need to control plant growth were raised. The special study discussed in this report was designed to address some of the ramifications of plant growth on disposal cells that have rock covers. The NRC has chosen rock covers over vegetative covers in the arid western United States because licenses cannot substantiate that the vegetative covers will be significantly greater than 30 percent and preferably 70 percent,'' which is the amount of vegetation required to reduce flow to a point of stability.'' The potential impacts of vegetation growing in rock covers are not addressed by the NRC (1990). The objectives, then, of this study were to determine the species of plants growing on two rock-covered disposal cells, study the rooting pattern of plants on these cells, and identify possible impacts of plant root penetration on these and other UMTRA Project rock-covered cells.

  5. Spectroscopic Evidence of Uranium Immobilization in Acidic Wetlands by Natural Organic Matter and Plant Roots

    EPA Science Inventory

    Biogeochemistry of uranium in wetlands plays important roles in U immobilization in storage ponds of U mining and processing facilities but has not been well understood. The objective of this work was to study molecular mechanisms responsible for high U retention by Savannah Ri...

  6. Spectroscopic Evidence of Uranium Immobilization in Acidic Wetlands by Natural Organic Matter and Plant Roots

    EPA Science Inventory

    Biogeochemistry of uranium in wetlands plays important roles in U immobilization in storage ponds of U mining and processing facilities but has not been well understood. The objective of this work was to study molecular mechanisms responsible for high U retention by Savannah Ri...

  7. Results from a "Proof-of-Concept" Demonstration of RF-Based Tracking of UF6 Cylinders during a Processing Operation at a Uranium Enrichment Plant

    SciTech Connect

    Pickett, Chris A; Kovacic, Donald N; Whitaker, J Michael; Younkin, James R; Hines, Jairus B; Laughter, Mark D; Morgan, Jim; Carrick, Bernie; Boyer, Brian; Whittle, K.

    2008-01-01

    Approved industry-standard cylinders are used globally for processing, storing, and transporting uranium hexafluoride (UF{sub 6}) at uranium enrichment plants. To ensure that cylinder movements at enrichment facilities occur as declared, the International Atomic Energy Agency (IAEA) must conduct time-consuming periodic physical inspections to validate facility records, cylinder identity, and containment. By using a robust system design that includes the capability for real-time unattended monitoring (of cylinder movements), site-specific rules-based event detection algorithms, and the capability to integrate with other types of monitoring technologies, one can build a system that will improve overall inspector effectiveness. This type of monitoring system can provide timely detection of safeguard events that could be used to ensure more timely and appropriate responses by the IAEA. It also could reduce reliance on facility records and have the additional benefit of enhancing domestic safeguards at the installed facilities. This paper will discuss the installation and evaluation of a radio-frequency- (RF-) based cylinder tracking system that was installed at a United States Enrichment Corporation Centrifuge Facility. This system was installed primarily to evaluate the feasibility of using RF technology at a site and the operational durability of the components under harsh processing conditions. The installation included a basic system that is designed to support layering with other safeguard system technologies and that applies fundamental rules-based event processing methodologies. This paper will discuss the fundamental elements of the system design, the results from this site installation, and future efforts needed to make this technology ready for IAEA consideration.

  8. Study on Evaluation of Project Management Data for Decommissioning of Uranium Refining and Conversion Plant - 12234

    SciTech Connect

    Usui, Hideo; Izumo, Sari; Tachibana, Mitsuo; Shibahara, Yuji; Morimoto, Yasuyuki; Tokuyasu, Takashi; Takahashi, Nobuo; Tanaka, Yoshio; Sugitsue, Noritake

    2012-07-01

    Some of nuclear facilities that would no longer be required have been decommissioned in JAEA (Japan Atomic Energy Agency). A lot of nuclear facilities have to be decommissioned in JAEA in near future. To implement decommissioning of nuclear facilities, it was important to make a rational decommissioning plan. Therefore, project management data evaluation system for dismantling activities (PRODIA code) has been developed, and will be useful for making a detailed decommissioning plan for an object facility. Dismantling of dry conversion facility in the uranium refining and conversion plant (URCP) at Ningyo-toge began in 2008. During dismantling activities, project management data such as manpower and amount of waste generation have been collected. Such collected project management data has been evaluated and used to establish a calculation formula to calculate manpower for dismantling equipment of chemical process and calculate manpower for using a green house (GH) which was a temporary structure for preventing the spread of contaminants during dismantling. In the calculation formula to calculate project management data related to dismantling of equipment, the relation of dismantling manpower to each piece of equipment was evaluated. Furthermore, the relation of dismantling manpower to each chemical process was evaluated. The results showed promise for evaluating dismantling manpower with respect to each chemical process. In the calculation formula to calculate project management data related to use of the GH, relations of GH installation manpower and removal manpower to GH footprint were evaluated. Furthermore, the calculation formula for secondary waste generation was established. In this study, project management data related to dismantling of equipment and use of the GH were evaluated and analyzed. The project management data, manpower for dismantling of equipment, manpower for installation and removal of GH, and secondary waste generation from GH were considered

  9. Chemical Interactions of Uranium in Water, Sediments, and Plants Along a Watershed Adjacent to the Abandoned Jackpile Mine

    NASA Astrophysics Data System (ADS)

    Blake, J.; De Vore, C. L.; Avasarala, S.; Ali, A.; Roldan, C.; Bowers, F.; Spilde, M.; Artyushkova, K.; Cerrato, J.

    2015-12-01

    The chemical interactions, mobility, and plant uptake of uranium (U) near abandoned mine wastes was investigated along the Rio Paguate, adjacent to the Jackpile Mine, located in Laguna Pueblo, New Mexico. Elevated U concentrations in surface water adjacent to mine waste range from 30 to 710 μg/L seasonally and decrease to 5.77 to 10.0 μg/L at a wetland 4.5 kilometers downstream of the mine. Although U concentrations in stream water are elevated, aqua regia acid digestions performed on co-located stream bed and stream bank sediments reveal that there is limited U accumulation on sediments along the reach between the mine and wetland, with most sediment concentrations being near the 3 mg/kg crustal average. However, U concentrations in sediments in the wetland are 4 times the background concentrations in the area. Individual results from salt cedar roots, stems, and leaves collected along the river transect show higher U concentrations in the roots adjacent to the mine waste (20 and 55 mg/kg) and lower in the stems and leaves. Translocation values calculated below 1 are evident in many of the plant samples, suggesting that U root to shoot translocation is minimal and U is accumulating in the roots. Concentrations of U in salt cedar roots from downstream of the mine waste decrease to 15 mg/kg. X-ray photoelectron spectroscopy analysis on sediment samples adjacent to the mine waste show a 75:25% ratio of Fe(III) to Fe(II), which can have an effect on adsorption properties. Electron microprobe results suggest that the ore in this area is present as a uranium-phosphate phase. Our results suggest that dilution, uptake by plants, and U sorption to wetland sediments are the dominant factors that help to decrease the U concentrations downstream of the mine.

  10. Uranium Immobilization in an Iron-Rich Rhizosphere of a Native Wetland Plant from the Savannah River Site under Reducing Conditions

    EPA Science Inventory

    The hypothesis of this study was that iron plaque formed on the roots of wetland plants and their rhizospheres create environmental conditions favorable for iron reducing bacteria that promote the in situ immobilization of uranium. Greenhouse microcosm studies were conducted usin...

  11. Uranium Immobilization in an Iron-Rich Rhizosphere of a Native Wetland Plant from the Savannah River Site under Reducing Conditions

    EPA Science Inventory

    The hypothesis of this study was that iron plaque formed on the roots of wetland plants and their rhizospheres create environmental conditions favorable for iron reducing bacteria that promote the in situ immobilization of uranium. Greenhouse microcosm studies were conducted usin...

  12. Uranium fate in wetland mesocosms: Effects of plants at two iron loadings with different pH values.

    PubMed

    Koster van Groos, Paul G; Kaplan, Daniel I; Chang, Hyun-Shik; Seaman, John C; Li, Dien; Peacock, Aaron D; Scheckel, Kirk G; Jaffé, Peter R

    2016-11-01

    Small-scale continuous flow wetland mesocosms (∼0.8 L) were used to evaluate how plant roots under different iron loadings affect uranium (U) mobility. When significant concentrations of ferrous iron (Fe) were present at circumneutral pH values, U concentrations in root exposed sediments were an order of magnitude greater than concentrations in root excluded sediments. Micro X-ray absorption near-edge structure (μ-XANES) spectroscopy indicated that U was associated with the plant roots primarily as U(VI) or U(V), with limited evidence of U(IV). Micro X-ray fluorescence (μ-XRF) of plant roots suggested that for high iron loading at circumneutral pH, U was co-located with Fe, perhaps co-precipitated with root Fe plaques, while for low iron loading at a pH of ∼4 the correlation between U and Fe was not significant, consistent with previous observations of U associated with organic matter. Quantitative PCR analyses indicated that the root exposed sediments also contained elevated numbers of Geobacter spp., which are likely associated with enhanced iron cycling, but may also reduce mobile U(VI) to less mobile U(IV) species.

  13. Solid-tumor mortality in the vicinity of uranium cycle facilities and nuclear power plants in Spain.

    PubMed Central

    López-Abente, G; Aragonés, N; Pollán, M

    2001-01-01

    To ascertain solid tumor mortality in towns near Spain's four nuclear power plants and four nuclear fuel facilities from 1975 to 1993, we conducted a mortality study based on 12,245 cancer deaths in 283 towns situated within a 30-km radius of the above installations. As nonexposed areas, we used 275 towns lying within a 50- to 100-km radius of each installation, matched by population size and sociodemographic characteristics (income level, proportion of active population engaged in farming, proportion of unemployed, percentage of illiteracy, and province). Using log-linear models, we examined relative risk for each area and trends in risk with increasing proximity to an installation. The results reveal a pattern of solid-tumor mortality in the vicinity of uranium cycle facilities, basically characterized by excess lung [relative risk (RR) 1.12, 95% confidence interval (CI), 1.02-1.25] and renal cancer mortality (RR 1.37, 95% CI, 1.07-1.76). Besides the effects of natural radiation, these results could well be evincing the influence on public health exerted by the environmental impact of mining. No such well-defined pattern appeared in the vicinity of nuclear power plants. Monitoring of cancer incidence and mortality is recommended in areas surrounding nuclear fuel facilities and nuclear power plants, and more specific studies are called for in areas adjacent to installations that have been fully operational for longer periods. In this regard, it is important to use dosimetric information in all future studies. PMID:11485872

  14. Near-Real-Time Geophysical and Biological Monitoring of Bioremediation Methods at a Uranium Mill Tailings Site in Rifle, Colorado

    NASA Astrophysics Data System (ADS)

    Tarrell, A. N.; Haas, A.; Revil, A.; Figueroa, L. A.; Rodriguez, D.; Smartgeo

    2010-12-01

    Bioremediation has been utilized on subsurface uranium contamination at the Rifle IRFC site in Colorado by injecting acetate as an electron donor. However, successfully monitoring the progress of subsurface bioremediation over time is difficult and requires long-term stewardship considerations to ensure cost effective treatment due to biological, chemical, and hydrological heterogeneity. In order to better understand the complex heterogeneities of the subsurface and the resultant effect on microbial activity, innovative subsurface monitoring techniques must be investigated. The key hypothesis of this work is that a combination of data from electrode-based microbial monitoring, self potential monitoring, oxidation reduction potential, and water level sensors will provide sufficient information for identifying and localizing bioremediation activity and will provide better predictions of deleterious biogeochemical change. In order to test the proof-of-concept of these sensing techniques and to deconvolve the redox activity from other electric potential changing events involved in bioremediation, a 2D tank (2.4m x 1.2m x 0.6m) experiment has been developed. Field material obtained from the Rifle IRFC site will be packed in the tank and an artificial groundwater will flow across the tank through constant-head boundaries. The experiment will utilize sensors for electrode-based microbial monitoring, self potential monitoring, oxidation-reduction potential, and water level monitoring. Electrode-based microbial monitoring will be used to estimate microbial activity by measuring how much electrical current indigenous bacteria are producing. Self potential monitoring will be used to measure the natural electrical voltage potential between sampled points, providing indications of when and where electrical activity is occurring; such as reduction of radionuclides. In addition to the application of sensing technologies, this work will explore the application of a wireless sensor

  15. Direct measurement of strontium-90 and uranium-238 in soils on a real-time basis: 1994 summary report

    SciTech Connect

    Schilk, A.J.; Hubbard, C.W.; Knopf, M.A.; Thompson, R.C.

    1995-04-01

    Traditional methodologies for quantitative characterization of radionuclide-contaminated soils over extended areas are often tedious, costly, and non-representative. A rapid characterization methodology was designed that provides reliable output with spatial resolution on the order of a few meters or less. It incorporates an innovative sensor of square plastic scintillating fibers that has been designed to be placed directly on or above a contaminated soil to detect and quantify high-energy beta particles associated with the decay chains of uranium and/or strontium. Under the direction and auspices of the DOE`s Characterization, Monitoring, and Sensor Technology Integrated Program, Pacific Northwest Laboratory (PNL) constructed a high-energy beta scintillation sensor that was optimized for the detection and quantification of uranium and strontium contamination in surface soils (in the presence of potentially interfering natural and anthropogenic radionuclides), demonstrated and evaluated this detector in various field and laboratory scenarios, and provides this document in completion of the aforementioned requirements.

  16. Comparison of measured and calculated uranium isotopic concentrations in cascade streams at the Paducah Gaseous Diffusion Plant

    SciTech Connect

    Blumkin, S.

    1982-06-16

    A test has been performed at the Paducah Gaseous Diffusion Plant (PGDP) in connection with studies for the US Arms Control and Disarmament Agency on the possibility of utilizing measurements of the concentrations of the minor uranium isotopes in /sup 235/U enrichment cascade external streams as a safeguards technique (MIST). This is the fourth plant test that has been performed in connection with the MIST studies, the first three having been done at the Oak Ridge Gaseous Diffusion Plant (ORGDP). The main objectives of the test were to measure the isotopic composition and flow rates of the plant external streams over a period of time; to design an appropriate plant model in the manner an IAEA safeguards team might do it and calculate the isotopic compositions of the plant streams; and to compare the calculated isotopic values with the measured ones. The calculated /sup 235/U to /sup 234/U concentration ratios in the product and tails streams did not match the average measured values in the high-power period as well as they did for the low-power period, when the same isotopic composition for natural U was assumed at both power levels - the actual composition of the natural U fed to the plant during the test not having been measured. Recalculation of the /sup 235/U to /sup 234/U concentrations with another assumed value for the /sup 234/U concentration in natural U, that is still within the range of reported observed values for it, resulted in better agreement with the measured plant stream values: + 0.7% for the product stream and + 0.2% in the tails stream for the single-cascade model and + 0.8% and - 0.7% respectively for a two-cascade plant model. The record on sources of the natural U that was fed during the test supports the assumption that the average /sup 234/U concentration in the natural U fed was probably different during the two operating periods.

  17. Investigation of the Uranium Solubility and Absorption

    NASA Astrophysics Data System (ADS)

    Anicin, I.; Banjanac, R.; Dragic, A.; Jokovic, D.; Udovicic, V.

    2005-01-01

    Particles of uranium oxides were produced by combustion of depleted uranium (isotopic contents: 99.8% 238U, 0.2% 235U). Solubility of uranium oxides as well as solubility of metallic uranium in water of various pH values was investigated by x-ray spectroscopy. Also, eventual absorption of dissolved uranium oxides by plants from uranium contaminated ground was investigated. A thin uranium-oxide layer was spread on the soil planted with various vegetables. After a two-month vegetation period the uranium originated radioactivity in the vegetable samples were measured by x-ray spectroscopy and compared with the measurements of samples treated likewise, but in soil without addition of uranium. Due to low radioactivity of the vegetable samples, the spectra were analyzed using Bayesian inference, too.

  18. Diffusive gradient in thin FILMS (DGT) compared with soil solution and labile uranium fraction for predicting uranium bioavailability to ryegrass.

    PubMed

    Duquène, L; Vandenhove, H; Tack, F; Van Hees, M; Wannijn, J

    2010-02-01

    The usefulness of uranium concentration in soil solution or recovered by selective extraction as unequivocal bioavailability indices for uranium uptake by plants is still unclear. The aim of the present study was to test if the uranium concentration measured by the diffusive gradient in thin films (DGT) technique is a relevant substitute for plant uranium availability in comparison to uranium concentration in the soil solution or uranium recovered by ammonium acetate. Ryegrass (Lolium perenne L. var. Melvina) is grown in greenhouse on a range of uranium spiked soils. The DGT-recovered uranium concentration (C(DGT)) was correlated with uranium concentration in the soil solution or with uranium recovered by ammonium acetate extraction. Plant uptake was better predicted by the summed soil solution concentrations of UO(2)(2+), uranyl carbonate complexes and UO(2)PO(4)(-). The DGT technique did not provide significant advantages over conventional methods to predict uranium uptake by plants. Copyright 2009 Elsevier Ltd. All rights reserved.

  19. Refurbishment of uranium hexafluoride cylinder storage yards C-745-K, L, M, N, and P and construction of a new uranium hexafluoride cylinder storage yard (C-745-T) at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    SciTech Connect

    1996-07-01

    The Paducah Gaseous Diffusion Plant (PGDP) is a uranium enrichment facility owned by the US Department of Energy (DOE). A residual of the uranium enrichment process is depleted uranium hexafluoride (UF6). Depleted UF6, a solid at ambient temperature, is stored in 32,200 steel cylinders that hold a maximum of 14 tons each. Storage conditions are suboptimal and have resulted in accelerated corrosion of cylinders, increasing the potential for a release of hazardous substances. Consequently, the DOE is proposing refurbishment of certain existing yards and construction of a new storage yard. This environmental assessment (EA) evaluates the impacts of the proposed action and no action and considers alternate sites for the proposed new storage yard. The proposed action includes (1) renovating five existing cylinder yards; (2) constructing a new UF6 storage yard; handling and onsite transport of cylinders among existing yards to accommodate construction; and (4) after refurbishment and construction, restacking of cylinders to meet spacing and inspection requirements. Based on the results of the analysis reported in the EA, DOE has determined that the proposed action is not a major Federal action that would significantly affect the quality of the human environment within the context of the National Environmental Policy Act of 1969. Therefore, DOE is issuing a Finding of No Significant Impact. Additionally, it is reported in this EA that the loss of less than one acre of wetlands at the proposed project site would not be a significant adverse impact.

  20. India's Worsening Uranium Shortage

    SciTech Connect

    Curtis, Michael M.

    2007-01-15

    As a result of NSG restrictions, India cannot import the natural uranium required to fuel its Pressurized Heavy Water Reactors (PHWRs); consequently, it is forced to rely on the expediency of domestic uranium production. However, domestic production from mines and byproduct sources has not kept pace with demand from commercial reactors. This shortage has been officially confirmed by the Indian Planning Commission’s Mid-Term Appraisal of the country’s current Five Year Plan. The report stresses that as a result of the uranium shortage, Indian PHWR load factors have been continually decreasing. The Uranium Corporation of India Ltd (UCIL) operates a number of underground mines in the Singhbhum Shear Zone of Jharkhand, and it is all processed at a single mill in Jaduguda. UCIL is attempting to aggrandize operations by establishing new mines and mills in other states, but the requisite permit-gathering and development time will defer production until at least 2009. A significant portion of India’s uranium comes from byproduct sources, but a number of these are derived from accumulated stores that are nearing exhaustion. A current maximum estimate of indigenous uranium production is 430t/yr (230t from mines and 200t from byproduct sources); whereas, the current uranium requirement for Indian PHWRs is 455t/yr (depending on plant capacity factor). This deficit is exacerbated by the additional requirements of the Indian weapons program. Present power generation capacity of Indian nuclear plants is 4350 MWe. The power generation target set by the Indian Department of Atomic Energy (DAE) is 20,000 MWe by the year 2020. It is expected that around half of this total will be provided by PHWRs using indigenously supplied uranium with the bulk of the remainder provided by breeder reactors or pressurized water reactors using imported low-enriched uranium.

  1. Real-time divergent evolution in plants driven by pollinators.

    PubMed

    Gervasi, Daniel D L; Schiestl, Florian P

    2017-03-14

    Pollinator-driven diversification is thought to be a major source of floral variation in plants. Our knowledge of this process is, however, limited to indirect assessments of evolutionary changes. Here, we employ experimental evolution with fast cycling Brassica rapa plants to demonstrate adaptive evolution driven by different pollinators. Our study shows pollinator-driven divergent selection as well as divergent evolution in plant traits. Plants pollinated by bumblebees evolved taller size and more fragrant flowers with increased ultraviolet reflection. Bumblebees preferred bumblebee-pollinated plants over hoverfly-pollinated plants at the end of the experiment, showing that plants had adapted to the bumblebees' preferences. Plants with hoverfly pollination became shorter, had reduced emission of some floral volatiles, but increased fitness through augmented autonomous self-pollination. Our study demonstrates that changes in pollinator communities can have rapid consequences on the evolution of plant traits and mating system.

  2. Real-time divergent evolution in plants driven by pollinators

    PubMed Central

    Gervasi, Daniel D. L.; Schiestl, Florian P

    2017-01-01

    Pollinator-driven diversification is thought to be a major source of floral variation in plants. Our knowledge of this process is, however, limited to indirect assessments of evolutionary changes. Here, we employ experimental evolution with fast cycling Brassica rapa plants to demonstrate adaptive evolution driven by different pollinators. Our study shows pollinator-driven divergent selection as well as divergent evolution in plant traits. Plants pollinated by bumblebees evolved taller size and more fragrant flowers with increased ultraviolet reflection. Bumblebees preferred bumblebee-pollinated plants over hoverfly-pollinated plants at the end of the experiment, showing that plants had adapted to the bumblebees' preferences. Plants with hoverfly pollination became shorter, had reduced emission of some floral volatiles, but increased fitness through augmented autonomous self-pollination. Our study demonstrates that changes in pollinator communities can have rapid consequences on the evolution of plant traits and mating system. PMID:28291771

  3. A review of the Y-12 Plant discharge of enriched uranium to the sanitary sewer (DEUSS)

    SciTech Connect

    Not Available

    1991-09-01

    The Oak Ridge Y-12 Plant is situated adjacent to the Oak Ridge city limits and is operated by the United States Department of Energy (DOE). The Y-12 Plant is located on 4,860 acres, which is collectively referred to as the Y-12 Plant site. Among the missions for which the facility is in existence are producing nuclear weapons components, supporting weapon design laboratories, and processing special nuclear materials (SNM). The Y-12 Plant is under the regulatory guidance of DOE Order 5400.5 and has complied with the technical requirements governing SNM since its issue. However, an in-depth review with appropriate documentation had not been performed, prior to the effect presented herein, to substantiate this claim. As a result of the solid waste issue, it was determined that other types of waste should be formally reviewed for content with respect to SNM. Therefore, a project was formed to investigate the conveyance of SNM through the sanitary sewer system. It is emphasized that this project addresses only effluent from the sanitary sewer system and not the storm sewer system. The project reviewed sanitary sewer data both for the Y-12 Plant and the Y-12 Plant site.

  4. Development of evaluation models of manpower needs for dismantling the dry conversion process-related equipment in uranium refining and conversion plant (URCP)

    SciTech Connect

    Sari Izumo; Hideo Usui; Mitsuo Tachibana; Yasuyuki Morimoto; Nobuo Takahashi; Takashi Tokuyasu; Yoshio Tanaka; Noritake Sugitsue

    2013-07-01

    Evaluation models for determining the manpower needs for dismantling various types of equipment in uranium refining and conversion plant (URCP) have been developed. The models are widely applicable to other uranium handling facilities. Additionally, a simplified model was developed for easily and accurately calculating the manpower needs for dismantling dry conversion process-related equipment (DP equipment). It is important to evaluate beforehand project management data such as manpower needs to prepare an optimized decommissioning plan and implement effective dismantling activity. The Japan Atomic Energy Agency (JAEA) has developed the project management data evaluation system for dismantling activities (PRODIA code), which can generate project management data using evaluation models. For preparing an optimized decommissioning plan, these evaluation models should be established based on the type of nuclear facility and actual dismantling data. In URCP, the dry conversion process of reprocessed uranium and others was operated until 1999, and the equipment related to the main process was dismantled from 2008 to 2011. Actual data such as manpower for dismantling were collected during the dismantling activities, and evaluation models were developed using the collected actual data on the basis of equipment classification considering the characteristics of uranium handling facility. (authors)

  5. Feasibility studies to establish at the Kazakhstan Ulba metallurgical plant the manufacturing capability to produce low-enriched uranium certified reference materials

    SciTech Connect

    Kuzminski, Jozef; Nesuhoff, J; Cratto, P; Pfennigwerth, G; Mikhailenko, A; Maliutina, I; Nations, J

    2009-01-01

    One of the salient features of the transition plan that the United States Department of Energy/National Nuclear Security Administration (DOE/NNSA) is presently implementing in the Former Soviet Union countries is the availability of uranium certified reference materials for calibration of nondestructive assay (NDA) measurement equipment. To address this challenge, DOE/NNSA and U.S. national laboratories have focused their cooperative efforts on establishing a reliable source for manufacturing, certifying, and supplying of such standards. The Ulba Metallurgical Plant (UMP), Kazakhstan, which processes large quantities of low-enriched uranium to produce ceramic fuel pellets for nuclear-powered reactors, is well situated to become a key supplier of low-enriched uranium certified reference materials for the country and Central Asia region. We have recently completed Phase I of a feasibility study to establish at UMP capabilities of manufacturing these standards. In this paper we will discuss details of a proposed methodology for uranium down-blending, material selection and characterization, and a proposed methodology of measurement by destructive (DA) and non-destructive (NDA) analysis to form a database for material certification by the competent State authorities in the Republic of Kazakhstan. In addition, we will discuss the prospect for manufacturing of such standards at UMP.

  6. Distribution of uranium-bearing phases in soils from Fernald

    SciTech Connect

    Buck, E.C.; Brown, N.R.; Dietz, N.L.

    1993-12-31

    Electron beam techniques have been used to characterize uranium-contaminated soils and the Fernald Site, Ohio. Uranium particulates have been deposited on the soil through chemical spills and from the operation of an incinerator plant on the site. The major uranium phases have been identified by electron microscopy as uraninite, autunite, and uranium phosphite [U(PO{sub 3}){sub 4}]. Some of the uranium has undergone weathering resulting in the redistribution of uranium within the soil.

  7. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Oak Ridge Gaseous Diffusion Plant Site

    SciTech Connect

    Not Available

    1991-09-01

    In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) technology, with the near-term goal to provide the necessary information to make a deployment decision by November 1992. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. A programmatic document for use in screening DOE sites to locate the U-AVLIS production plant was developed and implemented in two parts (Wolsko et al. 1991). The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were then subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the ORGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use, socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3. Following the site description and additional data requirements, Sec. 4 provides a short, qualitative assessment of potential environmental issues. 37 refs., 20 figs., 18 tabs.

  8. URANIUM RECOVERY

    DOEpatents

    Fitch, F.T.; Cruikshank, A.J.

    1958-10-28

    A process for recovering uranium from a solution of a diethyl dithiocarbaruate of uranium in an orgakic solvent substantially immiscible with water is presented. The process comprises brlnging the organic solutlon into intimate contact wlth an aqueous solution of ammonium carbonate, whereby the uranium passes to the aqueous carbonate solution as a soluble uranyl carbonate.

  9. Glaciimonas singularis sp. nov., isolated from a uranium mine wastewater treatment plant.

    PubMed

    Chung, Ana Paula; Tiago, Igor; Nobre, M Fernanda; Veríssimo, António; Morais, Paula V

    2013-06-01

    A bacterial strain, A2-57(T), recovered from a water sample collected in a uranium mine was taxonomically studied in detail. This strain was a Gram-reaction-negative, rod-shaped bacterium that grew optimally at 25 °C and at pH 6.0-7.0 and had a DNA G+C content of 55.0 mol%. Ubiquinone 8 (UQ-8) was the predominant respiratory quinone and the major fatty acids were C16:0, C17:0 cyclo, summed feature 3 (C16:1ω6c and/or ω7c and/or C15:0 iso 2-OH) and C18:1ω7c. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain A2-57(T) belonged to the family Oxalobacteraceae and formed a distinct branch with Glaciimonas immobilis Cr9-30(T). Strain A2-57(T) shared approximately 97.3% 16S rRNA sequence similarity with G. immobilis Cr9-30(T) and also showed high sequence similarity with members of the genera Herbaspirillum (96.3-97.0%) and Collimonas (96.2-97.0%). Although phylogenetically closely related to the type strain of G. immobilis, the low level of DNA-DNA hybridization between the two strains (21.6%) and several physiological and biochemical properties indicated that the novel strain could be clearly distinguished from G. immobilis LMG 25547(T). Therefore, it is concluded that strain A2-57(T) represents a novel species of the genus Glaciimonas, for which the name Glaciimonas singularis sp. nov. is proposed. The type strain is A2-57(T) (=CIP 110539(T)=LMG 27070(T)).

  10. In-situ removal and characterisation of uranium-containing particles from sediments surrounding the Fukushima Daiichi Nuclear Power Plant

    NASA Astrophysics Data System (ADS)

    Martin, P. G.; Griffiths, I.; Jones, C. P.; Stitt, C. A.; Davies-Milner, M.; Mosselmans, J. F. W.; Yamashiki, Y.; Richards, D. A.; Scott, T. B.

    2016-03-01

    Traditional methods to locate and subsequently study radioactive fallout particles have focused heavily on autoradiography coupled with in-situ analytical techniques. Presented here is the application of a Variable Pressure Scanning Electron Microscope with both backscattered electron and energy dispersive spectroscopy detectors, along with a micromanipulator setup and electron-hardening adhesive to isolate and remove individual particles before synchrotron radiation analysis. This system allows for a greater range of new and existing analytical techniques, at increased detail and speed, to be applied to the material. Using this method, it was possible to erform detailed energy dispersive spectroscopy and synchrotron radiation characterisation of material likely ejected from the Fukushima Daiichi Nuclear Power Plant found within a sediment sample collected from the edge of the 30 km exclusion zone. Particulate material sub-micron in maximum dimension examined during this work via energy dispersive spectroscopy was observed to contain uranium at levels between 19.68 and 28.35 weight percent, with the application of synchrotron radiation spectroscopy confirming its presence as a major constituent. With great effort and cost being devoted to the remediation of significant areas of eastern Japan affected by the incident, it is crucial to gain the greatest possible understanding of the nature of this contamination in order to inform the most appropriate clean-up response.

  11. 12. VIEW OF DEPLETED URANIUM INGOT AND MOLDS. DEPLETED URANIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW OF DEPLETED URANIUM INGOT AND MOLDS. DEPLETED URANIUM CASTING OPERATIONS CEASED IN 1988. (11/14/57) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  12. Vegetation composition and ²²⁶Ra uptake by native plant species at a uranium mill tailings impoundment in South China.

    PubMed

    Hu, Nan; Ding, Dexin; Li, Guangyue; Zheng, Jifang; Li, Le; Zhao, Weichao; Wang, Yongdong

    2014-03-01

    A field investigation was conducted for the vegetation composition and (226)Ra uptake by native plant species at a uranium mill tailings impoundment in South China. 80 species belonging to 67 genera in 32 families were recorded in the sampling sites. The Poaceae and Asteraceae were the dominant families colonizing the impoundment. The number of the plant species and vegetation community composition in the sampling sites seemed most closely related to the activities of (226)Ra and the pH value of the uranium tailings. The plant species in the sampling sites with relatively low activities of (226)Ra and relatively high pH value formed a relatively stable vegetation community. The plant species in the sampling sites with medium activities of (226)Ra and medium pH value formed the transitional vegetation community. The plant species in the sampling sites with relatively high activities of (226)Ra and relatively low pH value formed a simple unstable vegetation community that was similar to that on the unused grassland. The activities of (226)Ra and transfer factors (TFs) varied greatly with the plant species. The high activities of (226)Ra and TFs were found in the leaves of Pteris multifida (150.6 Bq/g of AW; 9.131), Pteridium aquilinum (122.2 Bq/g of AW; 7.409), and Dryopteris scottii (105.7 Bq/g of AW; 6.408). They satisfied the criteria for a hyperaccumulator for (226)Ra. They may be the candidates for phytoremediation of (226)Ra in the uranium mill tailings impoundment areas and the contaminated soils around. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Oxidative stress responses induced by uranium exposure at low pH in leaves of Arabidopsis thaliana plants.

    PubMed

    Saenen, Eline; Horemans, Nele; Vanhoudt, Nathalie; Vandenhove, Hildegarde; Biermans, Geert; van Hees, May; Wannijn, Jean; Vangronsveld, Jaco; Cuypers, Ann

    2015-12-01

    Anthropogenic activities have led to a widespread uranium (U) contamination in many countries. The toxic effects of U at the cellular level have mainly been investigated at a pH around 5.5, the optimal pH for hydroponically grown plants. However, since the speciation of U, and hence its toxicity, is strongly dependent on environmental factors such as the pH, it is important to investigate the effects of U at different environmentally relevant pH levels. Although U is poorly translocated from the roots to the shoots, resulting in a low U concentration in the leaves, it has been demonstrated that toxic effects in the leaves were already visible after 1 day exposure at pH 5.5, although only when exposed to relatively high U concentrations (100 μM). Therefore, the present study aimed to analyse the effects of different U concentrations (ranging from 0 to 100 μM) at pH 4.5 in leaves of Arabidopsis thaliana plants. Results indicate that U induces early senescence in A. thaliana leaves as was suggested by a decreased expression of CAT2 accompanied by an induction of CAT3 expression, a decreased CAT capacity and an increased lipid peroxidation. In addition, miRNA398b/c is involved in the regulation of the SOD response in the leaves. As such, an increased MIR398b/c expression was observed leading to a decreased transcript level of CSD1/2. Finally, the biosynthesis of ascorbate was induced after U exposure. This can point towards an important role for this metabolite in the scavenging of reactive oxygen species under U stress.

  14. 10 CFR Appendix J to Part 110 - Illustrative List of Uranium Conversion Plant Equipment and Plutonium Conversion Plant Equipment...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... feed for electromagnetic enrichment. Note: Plutonium conversion plants and systems may perform one or... systems are particularly adapted so as to avoid criticality and radiation effects and to minimize toxicity... radiation effects and to minimize toxicity hazards. Other processes include the fluorination of plutonium...

  15. A nested case-control study of multiple myeloma risk and uranium exposure among workers at the Oak Ridge Gaseous Diffusion Plant.

    PubMed

    Yiin, James H; Anderson, Jeri L; Daniels, Robert D; Seel, Evelyn A; Fleming, Donald A; Waters, Kathleen M; Chen, Pi-Hsueh

    2009-06-01

    The primary risk factors of multiple myeloma are age, race and sex, but several studies have found an association between radiological hazards and multiple myeloma. The purpose of this nested case-control study was to investigate whether workers with chronic low-level exposure to internally deposited uranium at the Oak Ridge Gaseous Diffusion Plant in eastern Tennessee were at higher risk of dying of multiple myeloma than those without occupational exposure to uranium, with the consideration of potential confounders of external ionizing radiation and occupational chemical hazards such as mercury, nickel and trichloroethylene. The main analyses were carried out using conditional logistic regression on 98 cases and 490 controls (five controls matched to each case on gender, race and age at risk). Our study showed a weak association between internal uranium dose estimated from urinalysis results and multiple myeloma risk: OR = 1.04 (95% CI 1.00-1.09) at 10 microGy with the inclusion of other risk factors. The parameter estimates and the corresponding odds ratios were very similar when internal doses were imputed for subjects without urine samples. Further studies that include updating this cohort and combining with workers from other gaseous diffusion plants are needed to investigate the relationship between multiple myeloma risk and radiation or other chemical exposures.

  16. Measurement of the enrichment of uranium in the pipework of a gas centrifuge enrichment plant

    SciTech Connect

    Packer, T.W.; Lees, E.W.; Close, D.; Nixon, K.V.; Pratt, J.C.; Strittmatter, R.

    1985-01-01

    The US and UK have been separately working on the development of a NDA instrument to determine the enrichment of gaseous UF/sub 6/ at low pressures in cascade header pipework in line with the conclusions of the Hexapartite Safeguards Project viz. the instrument is capable of making a ''go/no go'' decision of whether the enrichment is less than/greater than 20%. Recently, there has been a series of very useful technical exchanges of ideas and information between the two countries. This has led to a technical formulation for such an instrumentation based on ..gamma..-ray spectrometry which, although plant-specific in certain features, nevertheless is based on the same physical principles. Experimental results from commercially operating enrichment plants are very encouraging and indicate that a complete measurement including set up time on the pipe should be attainable in about 30 minutes when measuring pipes of diameter around 110 mm.

  17. Measurement of the enrichment of uranium in the pipework of a gas centrifuge enrichment plant

    SciTech Connect

    Packer, T W; Lees, E W; Close, D; Nixon, K V; Pratt, J C; Strittmatter, R

    1985-01-01

    The US and UK have been separately working on the development of a NDA instrument to determine the enrichment of gaseous UF/sub 6/ at low pressures in cascade header pipework in line with the conclusions of the Hexapartite Safeguards Project viz. the instrument is capable of making a ''go/no go'' decision of whether the enrichment is less than/greater than 20%. Recently, there has been a series of very useful technical exchanges of ideas and information between the two countries. This has led to a technical formulation for such an instrumentation based on ..gamma..-ray spectrometry which, although plant-specific in certain features, nevertheless is based on the same physical principles. Experimental results from commercially operating enrichment plants are very encouraging and indicate that a complete measurement including set up time on the pipe should be attainable in about 30 minutes when measuring pipes of diameter around 110 mm. 5 refs., 4 figs.

  18. Uranium deposits of Brazil

    SciTech Connect

    1991-09-01

    Brazil is a country of vast natural resources, including numerous uranium deposits. In support of the country`s nuclear power program, Brazil has developed the most active uranium industry in South America. Brazil has one operating reactor (Angra 1, a 626-MWe PWR), and two under construction. The country`s economic challenges have slowed the progress of its nuclear program. At present, the Pocos de Caldas district is the only active uranium production. In 1990, the Cercado open-pit mine produced approximately 45 metric tons (MT) U{sub 3}O{sub 8} (100 thousand pounds). Brazil`s state-owned uranium production and processing company, Uranio do Brasil, announced it has decided to begin shifting its production from the high-cost and nearly depleted deposits at Pocos de Caldas, to lower-cost reserves at Lagoa Real. Production at Lagoa Real is schedules to begin by 1993. In addition to these two districts, Brazil has many other known uranium deposits, and as a whole, it is estimated that Brazil has over 275,000 MT U{sub 3}O{sub 8} (600 million pounds U{sub 3}O{sub 8}) in reserves.

  19. Plant-pathogenic bacteria as biological weapons - real threats?

    PubMed

    Young, J M; Allen, C; Coutinho, T; Denny, T; Elphinstone, J; Fegan, M; Gillings, M; Gottwald, T R; Graham, J H; Iacobellis, N S; Janse, J D; Jacques, M-A; Lopez, M M; Morris, C E; Parkinson, N; Prior, P; Pruvost, O; Neto, J Rodrigues; Scortichini, M; Takikawa, Y; Upper, C D

    2008-10-01

    At present, much attention is being given to the potential of plant pathogens, including plant-pathogenic bacteria, as biological weapons/bioterror weapons. These two terms are sometimes used interchangeably and there is need for care in their application. It has been claimed that clandestine introduction of certain plant-pathogenic bacteria could cause such crop losses as to impact so significantly on a national economy and thus constitute a threat to national security. As a separate outcome, it is suggested that they could cause serious public alarm, perhaps constituting a source of terror. Legislation is now in place to regulate selected plant-pathogenic bacteria as potential weapons. However, we consider it highly doubtful that any plant-pathogenic bacterium has the requisite capabilities to justify such a classification. Even if they were so capable, the differentiation of pathogens into a special category with regulations that are even more restrictive than those currently applied in quarantine legislation of most jurisdictions offers no obvious benefit. Moreover, we believe that such regulations are disadvantageous insofar as they limit research on precisely those pathogens most in need of study. Whereas some human and animal pathogens may have potential as biological or bioterror weapons, we conclude that it is unlikely that any plant-pathogenic bacterium realistically falls into this category.

  20. Compton DIV: Using a Compton-Based Gamma-Ray Imager for Design Information Verification of Uranium Enrichment Plants

    SciTech Connect

    Burks, M; Verbeke, J; Dougan, A; Wang, T; Decman, D

    2009-07-04

    A feasibility study has been performed to determine the potential usefulness of Compton imaging as a tool for design information verification (DIV) of uranium enrichment plants. Compton imaging is a method of gamma-ray imaging capable of imaging with a 360-degree field of view over a broad range of energies. These systems can image a room (with a time span on the order of one hour) and return a picture of the distribution and composition of radioactive material in that room. The effectiveness of Compton imaging depends on the sensitivity and resolution of the instrument as well the strength and energy of the radioactive material to be imaged. This study combined measurements and simulations to examine the specific issue of UF{sub 6} gas flow in pipes, at various enrichment levels, as well as hold-up resulting from the accumulation of enriched material in those pipes. It was found that current generation imagers could image pipes carrying UF{sub 6} in less than one hour at moderate to high enrichment. Pipes with low enriched gas would require more time. It was also found that hold-up was more amenable to this technique and could be imaged in gram quantities in a fraction of an hour. another questions arises regarding the ability to separately image two pipes spaced closely together. This depends on the capabilities of the instrument in question. These results are described in detail. In addition, suggestions are given as to how to develop Compton imaging as a tool for DIV.

  1. Long-term biobarriers to plant and animal intrusions of uranium tailings. [24% trifluralin, 18% carbon black, and 58% polymer

    SciTech Connect

    Cline, J.F.; Burton, F.G.; Cataldo, D.A.; Skiens, W.E.; Gano, K.A.

    1982-09-01

    The objective of this project was to develop and evaluate the effectiveness of physical and chemical barriers designed to prevent plant and animal breachment of uranium mill tailings containment systems for an extended period of time. A polymeric carrier/biocide delivery system was developed and tested in the laboratory, greenhouse and field. A continuous flow technique was established to determine the release rates of the biocides from the PCD systems; polymeric carrier specifications were established. Studies were conducted to determine effective biocide concentrations required to produce a phytotoxic response and the relative rates of phytotoxin degradation resulting from chemical and biological breakdown in soils. The final PCD system developed was a pelletized system containing 24% trifluralin, 18% carbon black and 58% polymer. Pellets were placed in the soil at the Grand Junction U-tailings site at one in. and two in. intervals. Data obtained in the field determined that the pellets released enough herbicide to the soil layer to stop root elongation past the barrier. Physical barriers to subsurface movement of burrowing animals were investigated. Small crushed stone (1 to 1 1/2 in. diameter) placed over asphalt emulsion and multilayer soil seals proved effective as barriers to a small mammal (ground squirrels) but were not of sufficient size to stop a larger animal (the prairie dog). No penetrations were made through the asphalt emulsion or the clay layer of the multilayer soil seals by either of the two mammals tested. A literature survey was prepared and published on the burrowing habits of the animals that may be found at U-tailings sites.

  2. Uranium concentration monitor manual: 2300 system

    SciTech Connect

    Russo, P.A.; Sprinkle, J.K. Jr.; Stephens, M.M.

    1985-04-01

    This manual describes the design, operation, and procedures for measurement control for the automated uranium concentration monitor on the 2300 solvent extraction system at the Oak Ridge Y-12 Plant. The nonintrusive monitor provides a near-real time readout of uranium concentration at two locations simultaneously in the solvent extraction system for process monitoring and control. Detectors installed at the top of the extraction column and at the bottom of the backwash column acquire spectra of gamma rays from the solvent extraction solutions in the columns. Pulse-height analysis of these spectra gives the concentration of uranium in the organic product of the extraction column and in the aqueous product of the solvent extraction system. The visual readouts of concentrations for process monitoring are updated every 2 min for both detection systems. Simultaneously, the concentration results are shipped to a remote computer that has been installed by Y-12 to demonstrate automatic control of the solvent extraction system based on input of near-real time process operation information. 8 refs., 13 figs., 4 tabs.

  3. Smart Sensor for Real-Time Quantification of Common Symptoms Present in Unhealthy Plants

    PubMed Central

    Contreras-Medina, Luis M.; Osornio-Rios, Roque A.; Torres-Pacheco, Irineo; Romero-Troncoso, Rene de J.; Guevara-González, Ramon G.; Millan-Almaraz, Jesus R.

    2012-01-01

    Plant responses to physiological function disorders are called symptoms and they are caused principally by pathogens and nutritional deficiencies. Plant symptoms are commonly used as indicators of the health and nutrition status of plants. Nowadays, the most popular method to quantify plant symptoms is based on visual estimations, consisting on evaluations that raters give based on their observation of plant symptoms; however, this method is inaccurate and imprecise because of its obvious subjectivity. Computational Vision has been employed in plant symptom quantification because of its accuracy and precision. Nevertheless, the systems developed so far lack in-situ, real-time and multi-symptom analysis. There exist methods to obtain information about the health and nutritional status of plants based on reflectance and chlorophyll fluorescence, but they use expensive equipment and are frequently destructive. Therefore, systems able of quantifying plant symptoms overcoming the aforementioned disadvantages that can serve as indicators of health and nutrition in plants are desirable. This paper reports an FPGA-based smart sensor able to perform non-destructive, real-time and in-situ analysis of leaf images to quantify multiple symptoms presented by diseased and malnourished plants; this system can serve as indicator of the health and nutrition in plants. The effectiveness of the proposed smart-sensor was successfully tested by analyzing diseased and malnourished plants. PMID:22368496

  4. Smart sensor for real-time quantification of common symptoms present in unhealthy plants.

    PubMed

    Contreras-Medina, Luis M; Osornio-Rios, Roque A; Torres-Pacheco, Irineo; Romero-Troncoso, Rene de J; Guevara-González, Ramon G; Millan-Almaraz, Jesus R

    2012-01-01

    Plant responses to physiological function disorders are called symptoms and they are caused principally by pathogens and nutritional deficiencies. Plant symptoms are commonly used as indicators of the health and nutrition status of plants. Nowadays, the most popular method to quantify plant symptoms is based on visual estimations, consisting on evaluations that raters give based on their observation of plant symptoms; however, this method is inaccurate and imprecise because of its obvious subjectivity. Computational Vision has been employed in plant symptom quantification because of its accuracy and precision. Nevertheless, the systems developed so far lack in-situ, real-time and multi-symptom analysis. There exist methods to obtain information about the health and nutritional status of plants based on reflectance and chlorophyll fluorescence, but they use expensive equipment and are frequently destructive. Therefore, systems able of quantifying plant symptoms overcoming the aforementioned disadvantages that can serve as indicators of health and nutrition in plants are desirable. This paper reports an FPGA-based smart sensor able to perform non-destructive, real-time and in-situ analysis of leaf images to quantify multiple symptoms presented by diseased and malnourished plants; this system can serve as indicator of the health and nutrition in plants. The effectiveness of the proposed smart-sensor was successfully tested by analyzing diseased and malnourished plants.

  5. Application of the HGSYSTEM/UF{sub 6} model to simulate atmospheric dispersion of UF{sub 6} releases from uranium enrichment plants

    SciTech Connect

    Goode, W.D. Jr.; Bloom, S.G.; Keith, K.D. Jr.

    1995-03-01

    Uranium hexafluoride is a dense, reactive gas used in Gaseous Diffusion Plants (GDPs) to make uranium enriched in the {sup 235}U isotope. Large quantities of UF{sub 6} exist at the GDPs in the form of in-process gas and as a solid in storage cylinders; smaller amounts exist as hot liquid during transfer operations. If liquid UF{sub 6} is released to the environment, it immediately flashes to a solid and a dense gas that reacts rapidly with water vapor in the air to form solid particles of uranyl fluoride and hydrogen fluoride gas. Preliminary analyses were done on various accidental release scenarios to determine which scenarios must be considered in the safety analyses for the GDPS. These scenarios included gas releases due to failure of process equipment and liquid/gas releases resulting from a breach of transfer piping from a cylinder. A major goal of the calculations was to estimate the response time for mitigating actions in order to limit potential off-site consequences of these postulated releases. The HGSYSTEM/UF{sub 6} code was used to assess the consequences of these release scenarios. Inputs were developed from release calculations which included two-phase, choked flow followed by expansion to atmospheric pressure. Adjustments were made to account for variable release rates and multiple release points. Superpositioning of outputs and adjustments for exposure time were required to evaluate consequences based on health effects due to exposures to uranium and HF at a specific location.

  6. An investigation into the upward transport of uranium-series radionuclides in soils and uptake by plants.

    PubMed

    Pérez-Sánchez, D; Thorne, M C

    2014-09-01

    The upward migration of radionuclides in the (238)U decay series in soils and their uptake by plants is of interest in various contexts, including the geological disposal of radioactive waste and the remediation of former sites of uranium mining and milling. In order to investigate the likely patterns of behaviour of (238)U-series radionuclides being transported upward through the soil column, a detailed soil-plant model originally developed for studying the behaviour of (79)Se in soil-plant systems has been adapted to make it applicable to the (238)U series. By undertaking a reference case simulation and a series of sensitivity studies, it has been found that a wide variety of behaviour can be exhibited by radionuclides in the (238)U decay chain in soils, even when the source term is limited to being a constant flux of either (238)U or (226)Ra. Hydrological conditions are a primary factor, both in respect of the overall advective flow deeper in the soil, which controls the rate of upward migration, and in the influence of seasonally changing flow directions closer to the soil surface, which can result in the accumulation of radionuclides at specific depths irrespective of changes in sorption between the oxic and anoxic regions of the soil. However, such changes in sorption can also be significant in controlling the degree of accumulation that occurs. This importance of seasonally varying factors in controlling radionuclide transport in soils even in very long-term simulations is a strong argument against the use of annually averaged parameters in long-term assessment models. With a water table that was simulated to fluctuate seasonally from a substantial depth in soil to the surface soil layer, the timing of such variations in relation to the period of plant growth was found to have a major impact on the degree of uptake of radionuclides by plant roots. In long-term safety assessment studies it has sometimes been the practice to model the transport of (226)Ra in

  7. Field test of short-notice random inspections for inventory-change verification at a low-enriched-uranium fuel-fabrication plant

    SciTech Connect

    Fishbone, L.G. |; Moussalli, G.; Naegele, G.

    1995-05-01

    An approach of short-notice random inspections (SNRIs) for inventory-change verification can enhance the effectiveness and efficiency of international safeguards at natural or low-enriched uranium (LEU) fuel fabrication plants. According to this approach, the plant operator declares the contents of nuclear material items before knowing if an inspection will occur to verify them. Additionally, items about which declarations are newly made should remain available for verification for an agreed time. Then a statistical inference can be made from verification results for items verified during SNRIs to the entire populations, i.e. the entire strata, even if inspectors were not present when many items were received or produced. A six-month field test of the feasibility of such SNRIs took place at the Westinghouse Electric Corporation Commercial Nuclear Fuel Division during 1993. Westinghouse personnel made daily declarations about both feed and product items, uranium hexafluoride cylinders and finished fuel assemblies, using a custom-designed computer ``mailbox``. Safeguards inspectors from the IAEA conducted eight SNRIs to verify these declarations. They arrived unannounced at the plant, in most cases immediately after travel from Canada, where the IAEA maintains a regional office. Items from both strata were verified during the SNRIs by meant of nondestructive assay equipment.

  8. Field test of short-notice random inspections for inventory-change verification at a low-enriched-uranium fuel-fabrication plant: Preliminary summary

    SciTech Connect

    Fishbone, L.G. |; Moussalli, G.; Naegele, G.; Ikonomou, P.; Hosoya, M.; Scott, P.; Fager, J.; Sanders, C.; Colwell, D.; Joyner, C.J.

    1994-04-01

    An approach of short-notice random inspections (SNRIs) for inventory-change verification can enhance the effectiveness and efficiency of international safeguards at natural or low-enriched uranium (LEU) fuel fabrication plants. According to this approach, the plant operator declares the contents of nuclear material items before knowing if an inspection will occur to verify them. Additionally, items about which declarations are newly made should remain available for verification for an agreed time. This report details a six-month field test of the feasibility of such SNRIs which took place at the Westinghouse Electric Corporation Commercial Nuclear Fuel Division. Westinghouse personnel made daily declarations about both feed and product items, uranium hexafluoride cylinders and finished fuel assemblies, using a custom-designed computer ``mailbox``. Safeguards inspectors from the IAEA conducted eight SNRIs to verify these declarations. Items from both strata were verified during the SNRIs by means of nondestructive assay equipment. The field test demonstrated the feasibility and practicality of key elements of the SNRI approach for a large LEU fuel fabrication plant.

  9. In Plant Measurement and Analysis of Mixtures of Uranium and Plutonium TRU-Waste Using a {sup 252}Cf Shuffler Instrument

    SciTech Connect

    Hurd, J.R.

    1998-11-02

    The active-passive {sup 252}Cf shuffler instrument, installed and certified several years ago in Los Alamos National Laboratory's plutonium facility, has now been calibrated for different matrices to measure Waste Isolation Pilot Plant (WIPP)-destined transuranic (TRU)-waste. Little or no data currently exist for these types of measurements in plant environments where sudden large changes in the neutron background radiation can significantly distort the results. Measurements and analyses of twenty-two 55-gallon drums, consisting of mixtures of varying quantities of uranium and plutonium in mostly noncombustible matrices, have been recently completed at the plutonium facility. The calibration and measurement techniques, including the method used to separate out the plutonium component, will be presented and discussed. Calculations used to adjust for differences in uranium enrichment from that of the calibration standards will be shown. Methods used to determine various sources of both random and systematic error will be indicated. Particular attention will be directed to those problems identified as arising from the plant environment. The results of studies to quantify the aforementioned distortion effects in the data will be presented. Various solution scenarios will be outlined, along with those adopted here.

  10. Challenges using a {sup 252}Cf shuffler instrument in a plant environment to measure mixtures of uranium and plutonium transuranic waste

    SciTech Connect

    Hurd, J.R.

    1999-08-29

    An active-passive {sup 252}Cf shuffler instrument, installed and certified several years ago at Los Alamos National Laboratory's plutonium facility, has now been calibrated for different matrices to measure Waste Isolation Pilot Plant (WIPP)-destined transuranic (TRU) waste. Little or no data currently exist for these types of measurements in plant environments where sudden large changes in the neutron background radiation can significantly distort the results. Measurements and analyses of twenty-two 55-gallon drums, consisting of mixtures of varying quantities of uranium and plutonium in mostly noncombustible matrices, have been recently completed at the plutonium facility. The calibration and measurement techniques, including the method used to separate out the plutonium component, will be presented and discussed. Calculations used to adjust for differences in uranium enrichment from that of the calibration standards will be shown. Methods used to determine various sources of both random and systematic error will be indicated. Particular attention will be directed to those problems identified as arising from the plant environment. The results of studies to quantify the aforementioned distortion effects in the data will be presented. Various solution scenarios will be outlined, along with those adopted here.

  11. Uptake of 210Po by aquatic plants of a fresh water ecosystem around the uranium mill tailings management facility of Jaduguda, India.

    PubMed

    Jha, V N; Tripathi, R M; Sethy, N K; Sahoo, S K; Puranik, V D

    2013-10-01

    The present study was designed to investigate the uptake of Polonium-210 ((210)Po) by aquatic plants growing in a fresh water ecosystem around the tailings management facility of the uranium industry of Jaduguda, India. Evaluation of the activity concentration of (210)Po in aquatic plants, the concentration ratio of (210)Po from substrate to plants and the relationship of (210)Po with other stable elements were major objectives of the investigation. Based on the habitat, three types of plant were collected and analyzed for (210)Po activity estimation. Along with aquatic plants, effluent, surface water and bottom sediment were also collected and analyzed for (210)Po activity content. From the acid solution (210)Po was electrodeposited on brightly polished silver discs and counted for alpha activity in an alpha counter. The highest (210)Po activity concentration (4884 Bq kg(-1) fresh weight) was found in filamentous algae from residual water of the tailings pond. For sediment-rooted plants, a significant positive correlation (r = 0.91, p < 0.0001) was observed between plant and sediment activity concentration of (210)Po. For all of the three different groups of plants studied, highly significant correlations were observed between activity concentration of (210)Po and Cu with the significance level variation between 0.00-0.05 (both for linear and log transformed data).

  12. URANIUM COMPOSITIONS

    DOEpatents

    Allen, N.P.; Grogan, J.D.

    1959-05-12

    This patent relates to high purity uranium alloys characterized by improved stability to thermal cycling and low thermal neutron absorption. The high purity uranium alloy contains less than 0.1 per cent by weight in total amount of any ore or more of the elements such as aluminum, silicon, phosphorous, tin, lead, bismuth, niobium, and zinc.

  13. Isotopic ratio method for determining uranium contamination

    SciTech Connect

    Miles, R.E.; Sieben, A.K.

    1994-02-03

    The presence of high concentrations of uranium in the subsurface can be attributed either to contamination from uranium processing activities or to naturally occurring uranium. A mathematical method has been employed to evaluate the isotope ratios from subsurface soils at the Rocky Flats Nuclear Weapons Plant (RFP) and demonstrates conclusively that the soil contains uranium from a natural source and has not been contaminated with enriched uranium resulting from RFP releases. This paper describes the method used in this determination which has widespread application in site characterizations and can be adapted to other radioisotopes used in manufacturing industries. The determination of radioisotope source can lead to a reduction of the remediation effort.

  14. Uranium hexafluoride handling. Proceedings

    SciTech Connect

    Not Available

    1991-12-31

    The United States Department of Energy, Oak Ridge Field Office, and Martin Marietta Energy Systems, Inc., are co-sponsoring this Second International Conference on Uranium Hexafluoride Handling. The conference is offered as a forum for the exchange of information and concepts regarding the technical and regulatory issues and the safety aspects which relate to the handling of uranium hexafluoride. Through the papers presented here, we attempt not only to share technological advances and lessons learned, but also to demonstrate that we are concerned about the health and safety of our workers and the public, and are good stewards of the environment in which we all work and live. These proceedings are a compilation of the work of many experts in that phase of world-wide industry which comprises the nuclear fuel cycle. Their experience spans the entire range over which uranium hexafluoride is involved in the fuel cycle, from the production of UF{sub 6} from the naturally-occurring oxide to its re-conversion to oxide for reactor fuels. The papers furnish insights into the chemical, physical, and nuclear properties of uranium hexafluoride as they influence its transport, storage, and the design and operation of plant-scale facilities for production, processing, and conversion to oxide. The papers demonstrate, in an industry often cited for its excellent safety record, continuing efforts to further improve safety in all areas of handling uranium hexafluoride. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

  15. JACKETING URANIUM

    DOEpatents

    Saller, H.A.; Keeler, J.R.

    1959-07-14

    The bonding to uranium of sheathing of iron or cobalt, or nickel, or alloys thereof is described. The bonding is accomplished by electro-depositing both surfaces to be joined with a coating of silver and amalgamating or alloying the silver layer with mercury or indium. Then the silver alloy is homogenized by exerting pressure on an assembly of the uranium core and the metal jacket, reducing the area of assembly and heating the assembly to homogenize by diffusion.

  16. Isotopic evidence of natural uranium and spent fuel uranium releases into the environment.

    PubMed

    Pourcelot, L; Boulet, B; Le Corre, C; Loyen, J; Fayolle, C; Tournieux, D; Van Hecke, W; Martinez, B; Petit, J

    2011-02-01

    Uranium and plutonium isotopes were measured in soils, sediments and waters in an area subject to the past and present discharges from the uranium conversion plant of Malvési (France). The isotopes (236)U and (239)Pu are well known activation products of uranium and they prove to be powerful tracers of spent fuel releases in soils and sediments. On the other hand (234)U and (238)U activities measured in waters can be used to distinguish between releases and background uranium sources. Such findings contribute to improve the monitoring of the actinides releases by nuclear fuel facilities (mining sites, conversion, enrichment and fuel plants, reprocessing plants).

  17. Wetland Plant Guide for Assessing Habitat Impacts of Real-Time Salinity Management

    SciTech Connect

    Quinn, Nigel W.T.; Feldmann, Sara A.

    2004-10-15

    This wetland plant guide was developed to aid moist soil plant identification and to assist in the mapping of waterfowl and shorebird habitat in the Grassland Water District and surrounding wetland areas. The motivation for this habitat mapping project was a concern that real-time salinity management of wetland drainage might have long-term consequences for wildfowl habitat health--changes in wetland drawdown schedules might, over the long term, lead to increased soil salinity and other conditions unfavorable to propagation of the most desirable moist soil plants. Hence, the implementation of a program to monitor annual changes in the most common moist soil plants might serve as an index of habitat health and sustainability. Our review of the current scientific and popular literature failed to identify a good, comprehensive field guide that could be used to calibrate and verify high resolution remote sensing imagery, that we had started to use to develop maps of wetland moist soil plants in the Grassland Water District. Since completing the guide it has been used to conduct ground truthing field surveys using the California Native Plant Society methodology in 2004. Results of this survey and a previous wetland plant survey in 2003 are published in a companion LBNL publication summarizing 4 years of fieldwork to advance the science of real-time wetland salinity management.

  18. Roessing Uranium Limited

    SciTech Connect

    1991-04-01

    The government of Namibia, celebrating the first anniversary (Marsh 21) of the country`s independence from South African rule, is looking to Roessing Uranium Limited (RUL) to improve the economic health of the country. RUL is Namibia`s largest employer, producer of one third of the country`s exports and 13 percent of its domestic product. The Roessing mine is the second largest uranium mine in the world, producing over 108 million pounds U{sub 3}O{sub 8} from 1976 through 1989, and still holding an estimated 322 million pounds in reserves. Yet Roessing is one of the lowest grade uranium deposits ever commercially exploited, with an average grade of only 0.035 w/o U{sub 3}O{sub 8}. To efficiently develop such a low-grade deposit, RUL uses extensive real-time cost analysis systems and has the highest rock production rate (ore plus waste) of any uranium mine in the world, over 300 thousand tons per day.

  19. Uranium comparison by means of AMS and ICP-MS and Pu and 137Cs results around an Italian Nuclear Power Plant

    NASA Astrophysics Data System (ADS)

    De Cesare, M.; Tims, S. G.; Fifield, L. K.

    2015-04-01

    Italy built and commissioned 4 nuclear power plants between 1958-1978, which delivered a total of 1500 MW. All four were closed down after the Chernobyl accident following a referendum in 1987. One of the plants was Garigliano, commissioned in 1959. This plant used a 160 MW BWR1 (SEU of 2.3 %) and was operational from 1964 to 1979, when it was switched off for maintenance. It was definitively stopped in 1982, and is presently being decommissioned. We report here details on the chemistry procedure and on the measurements for soil samples, collected up to 4.5 km from the Nuclear Plant. A comparison between uranium (238U) concentration as determined by means of AMS (Accelerator Mass Spectrometry) and by ICP-MS (Inductively Coupled Plasma-Mass Spectrometry) techniques respectively at the ANU (Australian National University) and at the Ecowise company in Canberra, Australia, is reported, as well as 236U and 239;240Pu concentration results detected by AMS. 236U/238U and 240Pu/239Pu isotopic ratios by means of AMS are also provided. A contamination from Chernobyl is visible in the 137Cs/239+240Pu activity ratio measurements.

  20. REE, Uranium (U) and Thorium (Th) contents in Betula pendula leaf growing around Komsomolsk gold concentration plant tailing (Kemerovo region, Western Siberia, Russia)

    NASA Astrophysics Data System (ADS)

    Yusupov, D. V.; Karpenko, Yu A.

    2016-09-01

    The article deals with the research findings of peculiarities of REE, Uranium and Thorium distribution in the territory surrounding the tailing of former Komsomolsk gold concentration plant according to the data from Betula pendula leaf testing. In the leaf element composition the slight deficiency of MREE and substantial excess of HREE are presented. In the nearest impacted area around the tailing, La, Yb, U and Th content, and Th/U ratio are lower than in the distant buffer area. It is shown, that value of Th/U ratio and REE can be an indicator for geochemical transformations of technogenic landscapes in mining districts. The results of the research can be used for biomonitoring of the territory around the tailing.

  1. Uranium bombs

    NASA Astrophysics Data System (ADS)

    DeGroot, Gerard

    2009-11-01

    Enrico Fermi was a brilliant physicist, but he did occasionally get things wrong. In 1934 he famously bombarded a sample of uranium with neutrons. The result was astounding: the experiment had, Fermi concluded, produced element 93, later called neptunium. The German physicist Ida Noddack, however, came to an even more spectacular conclusion, namely that Fermi had split the uranium nucleus to produce lighter elements. Noddack's friend Otto Hahn judged that idea preposterous and advised her to keep quiet, since ridicule could ruin a female physicist. She ignored that advice, and was, indeed, scorned.

  2. Quantitation of transgenic plant DNA in leachate water: real-time polymerase chain reaction analysis.

    PubMed

    Gulden, Robert H; Lerat, Sylvain; Hart, Miranda M; Powell, Jeff R; Trevors, Jack T; Pauls, K Peter; Klironomos, John N; Swanton, Clarence J

    2005-07-27

    Roundup Ready (RR) genetically modified (GM) corn and soybean comprise a large portion of the annual planted acreage of GM crops. Plant growth and subsequent plant decomposition introduce the recombinant DNA (rDNA) into the soil environment, where its fate has not been completely researched. Little is known of the temporal and spatial distribution of plant-derived rDNA in the soil environment and in situ transport of plant DNA by leachate water has not been studied before. The objectives of this study were to determine whether sufficient quantities of plant rDNA were released by roots during growth and early decomposition to be detected in water collected after percolating through a soil profile and to determine the influence of temperature on DNA persistence in the leachate water. Individual plants of RR corn and RR soybean were grown in modified cylinders in a growth room, and the cylinders were flushed with rain water weekly. Immediately after collection, the leachate was subjected to DNA purification followed by rDNA quantification using real-time Polymerase Chain Reaction (PCR) analysis. To test the effects of temperature on plant DNA persistence in leachate water, water samples were spiked with known quantities of RR soybean or RR corn genomic DNA and DNA persistence was examined at 5, 15, and 25 degrees C. Differences in the amounts and temporal distributions of root-derived rDNA were observed between corn and soybean plants. The results suggest that rainfall events may distribute plant DNA throughout the soil and into leachate water. Half-lives of plant DNA in leachate water ranged from 1.2 to 26.7 h, and persistence was greater at colder temperatures (5 and 15 degrees C).

  3. US-Russian collaboration for enhancing nuclear materials protection, control, and accounting at the Elektrostal uranium fuel-fabrication plant

    SciTech Connect

    Smith, H.; Allentuck, J.; Barham, M.; Bishop, M.; Wentz, D.; Steele, B.; Bricker, K.; Cherry, R.; Snegosky, T.

    1996-09-01

    In September 1993, an implementing agreement was signed that authorized collaborative projects to enhance Russian national materials control and accounting, physical protection, and regulatory activities, with US assistance funded by the Nunn-Lugar Act. At the first US-Russian technical working group meeting in Moscow in February 1994, it was decided to identify a model facility where materials protection, control, and accounting (MPC and A) and regulatory projects could be carried out using proven technologies and approaches. The low-enriched uranium (LEU or RBMK and VVER) fuel-fabrication process at Elektrostal was selected, and collaborative work began in June 1994. Based on many factors, including initial successes at Elektrostal, the Russians expanded the cooperation by proposing five additional sites for MPC and A development: the Elektrostal medium-enriched uranium (MEU or BN) fuel-fabrication process and additional facilities at Podolsk, Dmitrovgrad, Obninsk, and Mayak. Since that time, multilaboratory teams have been formed to develop and implement MPC and A upgrades at the additional sites, and much new work is underway. This paper summarizes the current status of MPC and A enhancement projects in the LEU fuel-fabrication process and discusses the status of work that addresses similar enhancements in the MEU (BN) fuel processes at Elektrostal, under the recently expanded US-Russian MPC and A cooperation.

  4. An Economic Evaluation on Replacement Plan for Aged Thermal Power Plants through a Real Option Approach

    NASA Astrophysics Data System (ADS)

    Kato, Moritoshi; Zhou, Yicheng

    This paper presents a novel method to evaluate replacement plan for aged thermal power plants under uncertain circumstances through a real option approach. The most economical plan is selected among the three options: an option to operate an existing oil-fired thermal plant, an option to mothball it, and an option to abandon it and to construct an advanced gas combined cycle power plant (ACC) at the same time. Basic ideas of our model are: we use quadranomial approach in order to evaluate an option value consisted by two different uncertain assets; we consider cash flow with a dividend in order to reflect conditions of an aged oil-fired thermal plant and use the sequential compound option approach; we evaluate replacement time using quadranomial decision tree taking into account the options. We also analyze value and time of replacement using numerical examples. Our proposed method will be practically used for generation planning. For example it is possible to make priority quantitatively in replacements of aged thermal power plants by real option values. The target year of replacement may be set as a year when cumulative probability of replacement becomes over certain level.

  5. Real-Time Monitoring System for a Utility-Scale Photovoltaic Power Plant.

    PubMed

    Moreno-Garcia, Isabel M; Palacios-Garcia, Emilio J; Pallares-Lopez, Victor; Santiago, Isabel; Gonzalez-Redondo, Miguel J; Varo-Martinez, Marta; Real-Calvo, Rafael J

    2016-05-26

    There is, at present, considerable interest in the storage and dispatchability of photovoltaic (PV) energy, together with the need to manage power flows in real-time. This paper presents a new system, PV-on time, which has been developed to supervise the operating mode of a Grid-Connected Utility-Scale PV Power Plant in order to ensure the reliability and continuity of its supply. This system presents an architecture of acquisition devices, including wireless sensors distributed around the plant, which measure the required information. It is also equipped with a high-precision protocol for synchronizing all data acquisition equipment, something that is necessary for correctly establishing relationships among events in the plant. Moreover, a system for monitoring and supervising all of the distributed devices, as well as for the real-time treatment of all the registered information, is presented. Performances were analyzed in a 400 kW transformation center belonging to a 6.1 MW Utility-Scale PV Power Plant. In addition to monitoring the performance of all of the PV plant's components and detecting any failures or deviations in production, this system enables users to control the power quality of the signal injected and the influence of the installation on the distribution grid.

  6. Machining of uranium and uranium alloys

    SciTech Connect

    Morris, T.O.

    1981-12-14

    Uranium and uranium alloys can be readily machined by conventional methods in the standard machine shop when proper safety and operating techniques are used. Material properties that affect machining processes and recommended machining parameters are discussed. Safety procedures and precautions necessary in machining uranium and uranium alloys are also covered. 30 figures.

  7. Uranium hexaflouride freezer/sublimer process simulator/trainer

    SciTech Connect

    Carnal, C.L. ); Belcher, J.D.; Tapp, P.A.; Ruppel, F.R.; Wells, J.C. )

    1991-01-01

    This paper describes a software and hardware simulation of a freezer/sublimer unit used in gaseous diffusion processing of uranium hexafluoride (UF{sub 6}). The objective of the project was to build a plant simulator that reads control signals and produces plant signals to mimic the behavior of an actual plant. The model is based on physical principles and process data. Advanced Continuous Simulation Language (ACSL) was used to develop the model. Once the simulation was validated with actual plant process data, the ACSL model was translated into Advanced Communication and Control Oriented Language (ACCOL). A Bristol Babcock Distributed Process Controller (DPC) Model 3330 was the hardware platform used to host the ACCOL model and process the real world signals. The DPC will be used as a surrogate plant to debug control system hardware/software and to train operators to use the new distributed control system without disturbing the process. 2 refs., 4 figs.

  8. Application Research of Two Real-Time Fault Diagnostic Methods in the Nuclear Power Plants

    SciTech Connect

    Chun-Li Xie; Yong-Kuo Liu; Hong Xia

    2006-07-01

    In order to guarantee the safety of nuclear power plants (NPP), we built two real-time fault diagnosis systems adopting VISUAL BAS6.0 programming language, which apply neural network technology and data fusion technology respectively. The fault diagnosis systems interchange data with the simulator timely utilizing communication interface. We insert faults on simulator to test the two systems on line. The advantages and disadvantages are illuminated and contrasted through analyzing the faults diagnostic results off- line, which establish the foundation for the further research and application to the fault diagnosis system of the nuclear power plants. (authors)

  9. Application of linear programming techniques for controlling linear dynamic plants in real time

    NASA Astrophysics Data System (ADS)

    Gabasov, R.; Kirillova, F. M.; Ha, Vo Thi Thanh

    2016-03-01

    The problem of controlling a linear dynamic plant in real time given its nondeterministic model and imperfect measurements of the inputs and outputs is considered. The concepts of current distributions of the initial state and disturbance parameters are introduced. The method for the implementation of disclosable loop using the separation principle is described. The optimal control problem under uncertainty conditions is reduced to the problems of optimal observation, optimal identification, and optimal control of the deterministic system. To extend the domain where a solution to the optimal control problem under uncertainty exists, a two-stage optimal control method is proposed. Results are illustrated using a dynamic plant of the fourth order.

  10. Uranium immobilization in an iron-rich rhizosphere of a native wetland plant from the Savannah River Site under reducing conditions.

    PubMed

    Chang, Hyun-shik; Buettner, Shea W; Seaman, John C; Jaffé, Peter R; van Groos, Paul G Koster; Li, Dien; Peacock, Aaron D; Scheckel, Kirk G; Kaplan, Daniel I

    2014-08-19

    The hypothesis of this study was that iron plaques formed on the roots of wetland plants and their rhizospheres create environmental conditions favorable for iron reducing bacteria that promote the in situ immobilization of uranium. Greenhouse microcosm studies were conducted using native plants (Sparganium americanum) from a wetland located on the Savannah River Site, Aiken, SC. After iron plaques were established during a 73-day period by using an anoxic Fe(II)-rich nutrient solution, a U(VI) amended nutrient solution was added to the system for an additional two months. Compared to plant-free control microcosms, microcosms containing iron plaques successfully stimulated the growth of targeted iron reducing bacteria, Geobacter spp. Their population continuously increased after the introduction of the U(VI) nutrient solution. The reduction of some of the U(VI) to U(IV) by iron reducing bacteria was deduced based on the observations that the aqueous Fe(II) concentrations increased while the U(VI) concentrations decreased. The Fe(II) produced by the iron reducing bacteria was assumed to be reoxidized by the oxygen released from the roots. Advanced spectroscopic analyses revealed that a significant fraction of the U(VI) had been reduced to U(IV) and they were commonly deposited in association with phosphorus on the iron plaque.

  11. Flavonoids: a metabolic network mediating plants adaptation to their real estate.

    PubMed

    Mouradov, Aidyn; Spangenberg, German

    2014-01-01

    From an evolutionary perspective, the emergence of the sophisticated chemical scaffolds of flavonoid molecules represents a key step in the colonization of Earth's terrestrial environment by vascular plants nearly 500 million years ago. The subsequent evolution of flavonoids through recruitment and modification of ancestors involved in primary metabolism has allowed vascular plants to cope with pathogen invasion and damaging UV light. The functional properties of flavonoids as a unique combination of different classes of compounds vary significantly depending on the demands of their local real estate. Apart from geographical location, the composition of flavonoids is largely dependent on the plant species, their developmental stage, tissue type, subcellular localization, and key ecological influences of both biotic and abiotic origin. Molecular and metabolic cross-talk between flavonoid and other pathways as a result of the re-direction of intermediate molecules have been well investigated. This metabolic plasticity is a key factor in plant adaptive strength and is of paramount importance for early land plants adaptation to their local ecosystems. In human and animal health the biological and pharmacological activities of flavonoids have been investigated in great depth and have shown a wide range of anti-inflammatory, anti-oxidant, anti-microbial, and anti-cancer properties. In this paper we review the application of advanced gene technologies for targeted reprogramming of the flavonoid pathway in plants to understand its molecular functions and explore opportunities for major improvements in forage plants enhancing animal health and production.

  12. Flavonoids: a metabolic network mediating plants adaptation to their real estate

    PubMed Central

    Mouradov, Aidyn; Spangenberg, German

    2014-01-01

    From an evolutionary perspective, the emergence of the sophisticated chemical scaffolds of flavonoid molecules represents a key step in the colonization of Earth’s terrestrial environment by vascular plants nearly 500 million years ago. The subsequent evolution of flavonoids through recruitment and modification of ancestors involved in primary metabolism has allowed vascular plants to cope with pathogen invasion and damaging UV light. The functional properties of flavonoids as a unique combination of different classes of compounds vary significantly depending on the demands of their local real estate. Apart from geographical location, the composition of flavonoids is largely dependent on the plant species, their developmental stage, tissue type, subcellular localization, and key ecological influences of both biotic and abiotic origin. Molecular and metabolic cross-talk between flavonoid and other pathways as a result of the re-direction of intermediate molecules have been well investigated. This metabolic plasticity is a key factor in plant adaptive strength and is of paramount importance for early land plants adaptation to their local ecosystems. In human and animal health the biological and pharmacological activities of flavonoids have been investigated in great depth and have shown a wide range of anti-inflammatory, anti-oxidant, anti-microbial, and anti-cancer properties. In this paper we review the application of advanced gene technologies for targeted reprogramming of the flavonoid pathway in plants to understand its molecular functions and explore opportunities for major improvements in forage plants enhancing animal health and production. PMID:25426130

  13. Microscopy, culture, and quantitative real-time PCR examination confirm internalization of mycobacteria in plants.

    PubMed

    Kaevska, M; Lvoncik, S; Slana, I; Kulich, P; Kralik, P

    2014-07-01

    The environment is a reservoir of nontuberculous mycobacteria and is considered a source of infection for animals and humans. Mycobacteria can persist in different types of environments for a relatively long time. We have studied their possible internalization into plant tissue through intact, as well as damaged, root systems of different types of plants grown in vitro and under field conditions. The substrate into which plants were seeded was previously contaminated with different strains of Mycobacterium avium (10(8) to 10(10) cells/g of soil) and feces from animals with paratuberculosis. We detected M. avium subsp. avium, hominissuis, and paratuberculosis in the stems and leaves of the plants by both culture and real-time quantitative PCR. The presence of mycobacteria in the plant tissues was confirmed by microscopy. The concentration of mycobacteria found inside plant tissue was several orders of magnitude lower (up to 10(4) cells/g of tissue) than the initial concentration of mycobacteria present in the culture medium or substrate. These findings led us to the hypothesis that plants may play a role in the spread and transmission of mycobacteria to other organisms in the environment.

  14. Uranium from seawater

    SciTech Connect

    Gregg, D.; Folkendt, M.

    1982-09-21

    A novel process for recovering uranium from seawater is proposed and some of the critical technical parameters are evaluated. The process, in summary, consists of two different options for contacting adsorbant pellets with seawater without pumping the seawater. It is expected that this will reduce the mass handling requirements, compared to pumped seawater systems, by a factor of approximately 10/sup 5/, which should also result in a large reduction in initial capital investment. Activated carbon, possibly in combination with a small amount of dissolved titanium hydroxide, is expected to be the preferred adsorbant material instead of the commonly assumed titanium hydroxide alone. The activated carbon, after exposure to seawater, can be stripped of uranium with an appropriate eluant (probably an acid) or can be burned for its heating value (possible in a power plant) leaving the uranium further enriched in its ash. The uranium, representing about 1% of the ash, is then a rich ore and would be recovered in a conventional manner. Experimental results have indicated that activated carbon, acting alone, is not adequately effective in adsorbing the uranium from seawater. We measured partition coefficients (concentration ratios) of approximately 10/sup 3/ in seawater instead of the reported values of 10/sup 5/. However, preliminary tests carried out in fresh water show considerable promise for an extraction system that uses a combination of dissolved titanium hydroxide (in minute amounts) which forms an insoluble compound with the uranyl ion, and the insoluble compound then being sorbed out on activated carbon. Such a system showed partition coefficients in excess of 10/sup 5/ in fresh water. However, the system was not tested in seawater.

  15. Development of a Real-Time Microchip PCR System for Portable Plant Disease Diagnosis

    PubMed Central

    Kim, Hyun Soo; Cifci, Osman S.; Vaughn-Diaz, Vanessa L.; Ma, Bo; Kim, Sungman; Abdel-Raziq, Haron; Ong, Kevin; Jo, Young-Ki; Gross, Dennis C.; Shim, Won-Bo; Han, Arum

    2013-01-01

    Rapid and accurate detection of plant pathogens in the field is crucial to prevent the proliferation of infected crops. Polymerase chain reaction (PCR) process is the most reliable and accepted method for plant pathogen diagnosis, however current conventional PCR machines are not portable and require additional post-processing steps to detect the amplified DNA (amplicon) of pathogens. Real-time PCR can directly quantify the amplicon during the DNA amplification without the need for post processing, thus more suitable for field operations, however still takes time and require large instruments that are costly and not portable. Microchip PCR systems have emerged in the past decade to miniaturize conventional PCR systems and to reduce operation time and cost. Real-time microchip PCR systems have also emerged, but unfortunately all reported portable real-time microchip PCR systems require various auxiliary instruments. Here we present a stand-alone real-time microchip PCR system composed of a PCR reaction chamber microchip with integrated thin-film heater, a compact fluorescence detector to detect amplified DNA, a microcontroller to control the entire thermocycling operation with data acquisition capability, and a battery. The entire system is 25×16×8 cm3 in size and 843 g in weight. The disposable microchip requires only 8-µl sample volume and a single PCR run consumes 110 mAh of power. A DNA extraction protocol, notably without the use of liquid nitrogen, chemicals, and other large lab equipment, was developed for field operations. The developed real-time microchip PCR system and the DNA extraction protocol were used to successfully detect six different fungal and bacterial plant pathogens with 100% success rate to a detection limit of 5 ng/8 µl sample. PMID:24349341

  16. Development of a real-time microchip PCR system for portable plant disease diagnosis.

    PubMed

    Koo, Chiwan; Malapi-Wight, Martha; Kim, Hyun Soo; Cifci, Osman S; Vaughn-Diaz, Vanessa L; Ma, Bo; Kim, Sungman; Abdel-Raziq, Haron; Ong, Kevin; Jo, Young-Ki; Gross, Dennis C; Shim, Won-Bo; Han, Arum

    2013-01-01

    Rapid and accurate detection of plant pathogens in the field is crucial to prevent the proliferation of infected crops. Polymerase chain reaction (PCR) process is the most reliable and accepted method for plant pathogen diagnosis, however current conventional PCR machines are not portable and require additional post-processing steps to detect the amplified DNA (amplicon) of pathogens. Real-time PCR can directly quantify the amplicon during the DNA amplification without the need for post processing, thus more suitable for field operations, however still takes time and require large instruments that are costly and not portable. Microchip PCR systems have emerged in the past decade to miniaturize conventional PCR systems and to reduce operation time and cost. Real-time microchip PCR systems have also emerged, but unfortunately all reported portable real-time microchip PCR systems require various auxiliary instruments. Here we present a stand-alone real-time microchip PCR system composed of a PCR reaction chamber microchip with integrated thin-film heater, a compact fluorescence detector to detect amplified DNA, a microcontroller to control the entire thermocycling operation with data acquisition capability, and a battery. The entire system is 25 × 16 × 8 cm(3) in size and 843 g in weight. The disposable microchip requires only 8-µl sample volume and a single PCR run consumes 110 mAh of power. A DNA extraction protocol, notably without the use of liquid nitrogen, chemicals, and other large lab equipment, was developed for field operations. The developed real-time microchip PCR system and the DNA extraction protocol were used to successfully detect six different fungal and bacterial plant pathogens with 100% success rate to a detection limit of 5 ng/8 µl sample.

  17. Uranium, natural

    Integrated Risk Information System (IRIS)

    Uranium , natural ; CASRN 7440 - 61 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogeni

  18. URANIUM ALLOYS

    DOEpatents

    Seybolt, A.U.

    1958-04-15

    Uranium alloys containing from 0.1 to 10% by weight, but preferably at least 5%, of either zirconium, niobium, or molybdenum exhibit highly desirable nuclear and structural properties which may be improved by heating the alloy to about 900 d C for an extended period of time and then rapidly quenching it.

  19. A review of the environmental behavior of uranium derived from depleted uranium alloy penetrators

    SciTech Connect

    Erikson, R.L.; Hostetler, C.J.; Divine, J.R.; Price, K.R.

    1990-01-01

    The use of depleted uranium (DU) penetrators as armor-piercing projectiles in the field results in the release of uranium into the environment. Elevated levels of uranium in the environment are of concern because of radioactivity and chemical toxicity. In addition to the direct contamination of the soil with uranium, the penetrators will also chemically react with rainwater and surface water. Uranium may be oxidized and leached into surface water or groundwater and may subsequently be transported. In this report, we review some of the factors affecting the oxidation of the DU metal and the factors influencing the leaching and mobility of uranium through surface water and groundwater pathways, and the uptake of uranium by plants growing in contaminated soils. 29 refs., 10 figs., 3 tabs.

  20. Uranium industry annual 1996

    SciTech Connect

    1997-04-01

    The Uranium Industry Annual 1996 (UIA 1996) provides current statistical data on the US uranium industry`s activities relating to uranium raw materials and uranium marketing. The UIA 1996 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. Data on uranium raw materials activities for 1987 through 1996 including exploration activities and expenditures, EIA-estimated reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities for 1994 through 2006, including purchases of uranium and enrichment services, enrichment feed deliveries, uranium fuel assemblies, filled and unfilled market requirements, uranium imports and exports, and uranium inventories are shown in Chapter 2. A feature article, The Role of Thorium in Nuclear Energy, is included. 24 figs., 56 tabs.

  1. Uranium and thorium leached from uranium mill tailing of Guangdong Province, China and its implication for radiological risk.

    PubMed

    Wang, J; Liu, J; Zhu, L; Qi, J Y; Chen, Y H; Xiao, T F; Fu, S M; Wang, C L; Li, J W

    2012-11-01

    The paper focused on the leaching behaviour of uranium (U) and thorium (Th) from uranium mill tailing collected from the Uranium Mill Plant in Northern Guangdong Province, China. Distilled water (pH 6) and sulphuric acid solution (pH 4 and 3) were used as solvent for the leaching over 22 weeks. It was found that the cumulative leach fraction from the mill tailing was 0.1, 0.1 and 0.7 % for U release, and overall 0.01 % for Th release, using distilled water, sulphuric acid solution of pH 4 and pH 3 as leaching agents, respectively. The results indicate that (1) the release of U and Th in uranium mill tailing is a slow and long-term process; (2) surface dissolution is the main mechanism for the release of U and Th when sulphuric acid solution of pH 3 is employed as the leaching agent; (3) both U and Th are released by diffusion when using sulphuric acid solution of pH 4 as the leaching agent and (4) U is released by surface dissolution, while Th is released by diffusion when using distilled water as the leaching agent. The implication for radiological risk in the real environment was also discussed.

  2. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Uranium feed; natural uranium feed...) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The term uranium feed or natural uranium feed means natural uranium in the form of UF6 suitable for uranium...

  3. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Uranium feed; natural uranium feed...) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The term uranium feed or natural uranium feed means natural uranium in the form of UF6 suitable for uranium...

  4. Automated instruments for in-line accounting of highly enriched uranium at the Oak Ridge Y-12 Plant

    SciTech Connect

    Russo, P.A.; Strittmatter, R.B.; Sandford, E.L.; Stephens, M.M.; Brumfield, T.L.; Smith, S.E.; McCullough, E.E.; Jeter, I.W.; Bowers, G.L.

    1985-02-01

    Two automated nondestructive assay instruments developed at Los Alamos in support of nuclear materials accounting needs are currently operating in-line at the Oak Ridge Y-12 facility for recovery of highly enriched uranium (HEU). One instrument provides the HEU inventory in the secondary solvent extraction system, and the other monitors HEU concentration in the secondary intermediate evaporator. Both instruments were installed in December 1982. Operational evaluation of these instruments was a joint effort of Y-12 and Los Alamos personnel. This evaluation included comparison of the solvent extraction system inventories with direct measurements performed on the dumped solution components of the solvent extraction system and comparison of concentration assay results with the external assays of samples withdrawn from the process. The function and design of the instruments and detailed results of the operational evaluation are reported.

  5. Development of an Alternative Release Limit for a Former Uranium and Thorium Processing Plant in Cushing Oklahoma

    SciTech Connect

    Thatcher, A.H.

    2007-07-01

    The purpose of this presentation will be to describe how, through dose modeling and analysis, a complex site was able to obtain an Alternative Release Limit (ARL) that adequately protected the environment, met regulatory approval, and saved money in the process. The Kerr-McGee Refinery Site in Cushing, OK supported an experimental facility that processed nuclear fuel materials from 1963 to 1966. Radiological contaminants at the site as a result of operations consist of natural thorium and isotopes of uranium (Th-228, Th-232, U-234, U-235 and U-238). Site contamination existed in both surface and sub-surface soils and within a shallow aquifer. After the soil was remediated to acceptable regulatory limits, however, the potential existed for residual groundwater contamination to result in exposure to individuals following site closure. Traditional exposure pathway analysis for the resident farmer seemed to indicate that this exposure was excessive. A closer look at the exposure pathways present in this rural location showed that groundwater contamination existed in a shallow aquifer insufficient to support significant irrigation activities and was of sufficiently poor water quality that it could not be used for drinking water. Through the determination of aquifer yield pumping tests, agreement from the Oklahoma Department of Environmental Quality, and sensitivity and uncertainty analysis using Monte Carlo techniques, it was shown that the average member of the critical population was adequately protected in the current site configuration without further remediation. This paper describes the analytical methods and models used to apply the general dose limit of 0.25 mSv yr{sup -1} (25 mrem yr{sup -1}) to the particulars of the Cushing Site, and demonstrates how these methods achieved a much higher ARL for total uranium in groundwater that was accepted by the regulators and achieved significant savings for the Licensee. (authors)

  6. Real-Time Monitoring System for a Utility-Scale Photovoltaic Power Plant

    PubMed Central

    Moreno-Garcia, Isabel M.; Palacios-Garcia, Emilio J.; Pallares-Lopez, Victor; Santiago, Isabel; Gonzalez-Redondo, Miguel J.; Varo-Martinez, Marta; Real-Calvo, Rafael J.

    2016-01-01

    There is, at present, considerable interest in the storage and dispatchability of photovoltaic (PV) energy, together with the need to manage power flows in real-time. This paper presents a new system, PV-on time, which has been developed to supervise the operating mode of a Grid-Connected Utility-Scale PV Power Plant in order to ensure the reliability and continuity of its supply. This system presents an architecture of acquisition devices, including wireless sensors distributed around the plant, which measure the required information. It is also equipped with a high-precision protocol for synchronizing all data acquisition equipment, something that is necessary for correctly establishing relationships among events in the plant. Moreover, a system for monitoring and supervising all of the distributed devices, as well as for the real-time treatment of all the registered information, is presented. Performances were analyzed in a 400 kW transformation center belonging to a 6.1 MW Utility-Scale PV Power Plant. In addition to monitoring the performance of all of the PV plant’s components and detecting any failures or deviations in production, this system enables users to control the power quality of the signal injected and the influence of the installation on the distribution grid. PMID:27240365

  7. FPGA-based fused smart sensor for real-time plant-transpiration dynamic estimation.

    PubMed

    Millan-Almaraz, Jesus Roberto; de Jesus Romero-Troncoso, Rene; Guevara-Gonzalez, Ramon Gerardo; Contreras-Medina, Luis Miguel; Carrillo-Serrano, Roberto Valentin; Osornio-Rios, Roque Alfredo; Duarte-Galvan, Carlos; Rios-Alcaraz, Miguel Angel; Torres-Pacheco, Irineo

    2010-01-01

    Plant transpiration is considered one of the most important physiological functions because it constitutes the plants evolving adaptation to exchange moisture with a dry atmosphere which can dehydrate or eventually kill the plant. Due to the importance of transpiration, accurate measurement methods are required; therefore, a smart sensor that fuses five primary sensors is proposed which can measure air temperature, leaf temperature, air relative humidity, plant out relative humidity and ambient light. A field programmable gate array based unit is used to perform signal processing algorithms as average decimation and infinite impulse response filters to the primary sensor readings in order to reduce the signal noise and improve its quality. Once the primary sensor readings are filtered, transpiration dynamics such as: transpiration, stomatal conductance, leaf-air-temperature-difference and vapor pressure deficit are calculated in real time by the smart sensor. This permits the user to observe different primary and calculated measurements at the same time and the relationship between these which is very useful in precision agriculture in the detection of abnormal conditions. Finally, transpiration related stress conditions can be detected in real time because of the use of online processing and embedded communications capabilities.

  8. FPGA-based Fused Smart Sensor for Real-Time Plant-Transpiration Dynamic Estimation

    PubMed Central

    Millan-Almaraz, Jesus Roberto; de Jesus Romero-Troncoso, Rene; Guevara-Gonzalez, Ramon Gerardo; Contreras-Medina, Luis Miguel; Carrillo-Serrano, Roberto Valentin; Osornio-Rios, Roque Alfredo; Duarte-Galvan, Carlos; Rios-Alcaraz, Miguel Angel; Torres-Pacheco, Irineo

    2010-01-01

    Plant transpiration is considered one of the most important physiological functions because it constitutes the plants evolving adaptation to exchange moisture with a dry atmosphere which can dehydrate or eventually kill the plant. Due to the importance of transpiration, accurate measurement methods are required; therefore, a smart sensor that fuses five primary sensors is proposed which can measure air temperature, leaf temperature, air relative humidity, plant out relative humidity and ambient light. A field programmable gate array based unit is used to perform signal processing algorithms as average decimation and infinite impulse response filters to the primary sensor readings in order to reduce the signal noise and improve its quality. Once the primary sensor readings are filtered, transpiration dynamics such as: transpiration, stomatal conductance, leaf-air-temperature-difference and vapor pressure deficit are calculated in real time by the smart sensor. This permits the user to observe different primary and calculated measurements at the same time and the relationship between these which is very useful in precision agriculture in the detection of abnormal conditions. Finally, transpiration related stress conditions can be detected in real time because of the use of online processing and embedded communications capabilities. PMID:22163656

  9. Validation of real-time PCR assays for bioforensic detection of model plant pathogens.

    PubMed

    James, Mindy; Blagden, Trenna; Moncrief, Ian; Burans, James P; Schneider, Katherine; Fletcher, Jacqueline

    2014-03-01

    The U.S. agricultural sector is vulnerable to intentionally introduced microbial threats because of its wide and open distribution and economic importance. To investigate such events, forensically valid assays for plant pathogen detection are needed. In this work, real-time PCR assays were developed for three model plant pathogens: Pseudomonas syringae pathovar tomato, Xylella fastidiosa, and Wheat streak mosaic virus. Validation included determination of the linearity and range, limit of detection, sensitivity, specificity, and exclusivity of each assay. Additionally, positive control plasmids, distinguishable from native signature by restriction enzyme digestion, were developed to support forensic application of the assays. Each assay displayed linear amplification of target nucleic acid, detected 100 fg or less of target nucleic acid, and was specific to its target pathogen. Results obtained with these model pathogens provide the framework for development and validation of similar assays for other plant pathogens of high consequence.

  10. Test Cases for Wind Power Plant Dynamic Models on Real-Time Digital Simulator: Preprint

    SciTech Connect

    Singh, M.; Muljadi, E.; Gevorgian, V.

    2012-06-01

    The objective of this paper is to present test cases for wind turbine generator and wind power plant models commonly used during commissioning of wind power plants to ensure grid integration compatibility. In this paper, different types of wind power plant models based on the Western Electricity Coordinating Council Wind Generator Modeling Group's standardization efforts are implemented on a real-time digital simulator, and different test cases are used to gauge their grid integration capability. The low-voltage ride through and reactive power support capability and limitations of wind turbine generators under different grid conditions are explored. Several types of transient events (e.g., symmetrical and unsymmetrical faults, frequency dips) are included in the test cases. The differences in responses from different types of wind turbine are discussed in detail.

  11. Degradation problems with the solvent extraction organic at Roessing uranium

    SciTech Connect

    Munyungano, Brodrick; Feather, Angus; Virnig, Michael

    2008-07-01

    Roessing Uranium Ltd recovers uranium from a low-grade ore in Namibia. Uranium is recovered and purified from an ion-exchange eluate in a solvent-extraction plant. The solvent-extraction plant uses Alamine 336 as the extractant for uranium, with isodecanol used as a phase modifier in Sasol SSX 210, an aliphatic hydrocarbon diluent. Since the plant started in the mid 1970's, there have been a few episodes where the tertiary amine has been quickly and severely degraded when the plant was operated outside certain operating parameters. The Rossing experience is discussed in more detail in this paper. (authors)

  12. Derived enriched uranium market

    SciTech Connect

    Rutkowski, E.

    1996-12-01

    The potential impact on the uranium market of highly enriched uranium from nuclear weapons dismantling in the Russian Federation and the USA is analyzed. Uranium supply, conversion, and enrichment factors are outlined for each country; inventories are also listed. The enrichment component and conversion components are expected to cause little disruption to uranium markets. The uranium component of Russian derived enriched uranium hexafluoride is unresolved; US legislation places constraints on its introduction into the US market.

  13. Estimation of transgene copy number in transformed citrus plants by quantitative multiplex real-time PCR.

    PubMed

    Omar, Ahmad A; Dekkers, Marty G H; Graham, James H; Grosser, Jude W

    2008-01-01

    Quantitative real-time PCR (qRT-PCR) was adapted to estimate transgene copy number of the rice Xa21 gene in transgenic citrus plants. This system used TaqMan qRT-PCR and the endogenous citrus gene encoding for lipid transfer protein (LTP). Transgenic "Hamlin" sweet orange plants were generated using two different protoplast-GFP transformation systems: cotransformation and single plasmid transformation. A dilution series of genomic DNA from one of the transgenic lines was used to generate a standard curve for the endogenous LTP and the transgene Xa21. This standard curve was used for relative quantification of the endogenous gene and the transgene. Copy numbers of the transgene Xa21 detected from qRT-PCR analysis correlated with that from Southern blot analysis (r = 0.834). Thus, qRT-PCR is an efficient means of estimating copy number in transgenic citrus plants. This analysis can be performed at much earlier stages of transgenic plant development than southern blot analysis, which expedites investigation of transgenes in slow-growing woody plants.

  14. Toxicological Investigation of Radioactive Uranium in Seawater

    PubMed Central

    Bae, Jeong Mi; Kim, Jin

    2012-01-01

    Trace uranium detection measurement was performed using DNA immobilized on a graphite pencil electrode (DGE). The developed probe was connected to the portable handheld voltammetric systems used for seawater analysis. The sensitive voltammogram was obtained within only 30 s accumulation time, and the anodic stripping working range was attained at 100~800 μg/l U and 10~50 μg/l. The statistic relative standard deviation of 30.0 mg/l with the 15th stripping was 0.2115. Here, toxicological and analytical application was performed in the seawater survey in a contaminated power plant controlling water. The results were found to be applicable for real-time toxicological assay for trace control. PMID:24278591

  15. Uranium Industry Annual, 1992

    SciTech Connect

    Not Available

    1993-10-28

    The Uranium Industry Annual provides current statistical data on the US uranium industry for the Congress, Federal and State agencies, the uranium and electric utility industries, and the public. The feature article, ``Decommissioning of US Conventional Uranium Production Centers,`` is included. Data on uranium raw materials activities including exploration activities and expenditures, resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities including domestic uranium purchases, commitments by utilities, procurement arrangements, uranium imports under purchase contracts and exports, deliveries to enrichment suppliers, inventories, secondary market activities, utility market requirements, and uranium for sale by domestic suppliers are presented in Chapter 2.

  16. The quantitative real-time polymerase chain reaction for the analysis of plant gene expression.

    PubMed

    Fitzgerald, Timothy L; McQualter, Richard B

    2014-01-01

    The quantitative real-time polymerase chain reaction is used to simultaneously amplify and quantify a targeted DNA molecule. It can be used to determine exact copy number of a molecule within a sample and/or to compare the quantity of a molecule between samples. When combined with reverse transcription, it is a powerful tool for the analysis of gene expression, and it is widely used for this purpose in plant species. Here we provide an introduction to fundamental concepts relevant for the analysis of gene expression in plants using this technique and a protocol for quantification of the relative expression of a sucrose phosphate synthase gene along the maturation gradient of a sugarcane leaf.

  17. A real-time phenotyping framework using machine learning for plant stress severity rating in soybean.

    PubMed

    Naik, Hsiang Sing; Zhang, Jiaoping; Lofquist, Alec; Assefa, Teshale; Sarkar, Soumik; Ackerman, David; Singh, Arti; Singh, Asheesh K; Ganapathysubramanian, Baskar

    2017-01-01

    Phenotyping is a critical component of plant research. Accurate and precise trait collection, when integrated with genetic tools, can greatly accelerate the rate of genetic gain in crop improvement. However, efficient and automatic phenotyping of traits across large populations is a challenge; which is further exacerbated by the necessity of sampling multiple environments and growing replicated trials. A promising approach is to leverage current advances in imaging technology, data analytics and machine learning to enable automated and fast phenotyping and subsequent decision support. In this context, the workflow for phenotyping (image capture → data storage and curation → trait extraction → machine learning/classification → models/apps for decision support) has to be carefully designed and efficiently executed to minimize resource usage and maximize utility. We illustrate such an end-to-end phenotyping workflow for the case of plant stress severity phenotyping in soybean, with a specific focus on the rapid and automatic assessment of iron deficiency chlorosis (IDC) severity on thousands of field plots. We showcase this analytics framework by extracting IDC features from a set of ~4500 unique canopies representing a diverse germplasm base that have different levels of IDC, and subsequently training a variety of classification models to predict plant stress severity. The best classifier is then deployed as a smartphone app for rapid and real time severity rating in the field. We investigated 10 different classification approaches, with the best classifier being a hierarchical classifier with a mean per-class accuracy of ~96%. We construct a phenotypically meaningful 'population canopy graph', connecting the automatically extracted canopy trait features with plant stress severity rating. We incorporated this image capture → image processing → classification workflow into a smartphone app that enables automated real-time evaluation of IDC

  18. Behavior and distribution of heavy metals including rare Earth elements, thorium, and uranium in sludge from industry water treatment plant and recovery method of metals by biosurfactants application.

    PubMed

    Gao, Lidi; Kano, Naoki; Sato, Yuichi; Li, Chong; Zhang, Shuang; Imaizumi, Hiroshi

    2012-01-01

    In order to investigate the behavior, distribution, and characteristics of heavy metals including rare earth elements (REEs), thorium (Th), and uranium (U) in sludge, the total and fractional concentrations of these elements in sludge collected from an industry water treatment plant were determined and compared with those in natural soil. In addition, the removal/recovery process of heavy metals (Pb, Cr, and Ni) from the polluted sludge was studied with biosurfactant (saponin and sophorolipid) elution by batch and column experiments to evaluate the efficiency of biosurfactant for the removal of heavy metals. Consequently, the following matters have been largely clarified. (1) Heavy metallic elements in sludge have generally larger concentrations and exist as more unstable fraction than those in natural soil. (2) Nonionic saponin including carboxyl group is more efficient than sophorolipid for the removal of heavy metals in polluted sludge. Saponin has selectivity for the mobilization of heavy metals and mainly reacts with heavy metals in F3 (the fraction bound to carbonates) and F5 (the fraction bound to Fe-Mn oxides). (3) The recovery efficiency of heavy metals (Pb, Ni, and Cr) reached about 90-100% using a precipitation method with alkaline solution.

  19. Behavior and Distribution of Heavy Metals Including Rare Earth Elements, Thorium, and Uranium in Sludge from Industry Water Treatment Plant and Recovery Method of Metals by Biosurfactants Application

    PubMed Central

    Gao, Lidi; Kano, Naoki; Sato, Yuichi; Li, Chong; Zhang, Shuang; Imaizumi, Hiroshi

    2012-01-01

    In order to investigate the behavior, distribution, and characteristics of heavy metals including rare earth elements (REEs), thorium (Th), and uranium (U) in sludge, the total and fractional concentrations of these elements in sludge collected from an industry water treatment plant were determined and compared with those in natural soil. In addition, the removal/recovery process of heavy metals (Pb, Cr, and Ni) from the polluted sludge was studied with biosurfactant (saponin and sophorolipid) elution by batch and column experiments to evaluate the efficiency of biosurfactant for the removal of heavy metals. Consequently, the following matters have been largely clarified. (1) Heavy metallic elements in sludge have generally larger concentrations and exist as more unstable fraction than those in natural soil. (2) Nonionic saponin including carboxyl group is more efficient than sophorolipid for the removal of heavy metals in polluted sludge. Saponin has selectivity for the mobilization of heavy metals and mainly reacts with heavy metals in F3 (the fraction bound to carbonates) and F5 (the fraction bound to Fe-Mn oxides). (3) The recovery efficiency of heavy metals (Pb, Ni, and Cr) reached about 90–100% using a precipitation method with alkaline solution. PMID:22693485

  20. The 3D reconstruction of greenhouse tomato plant based on real organ samples and parametric L-system

    NASA Astrophysics Data System (ADS)

    Xin, Longjiao; Xu, Lihong; Li, Dawei; Fu, Daichang

    2014-04-01

    In this paper, a fast and effective 3D reconstruction method for the growth of greenhouse tomato plant is proposed by using real organ samples and a parametric L-system. By analyzing the stereo structure of tomato plant, we extracts rules and parameters to assemble an L-system that is able to simulate the plant growth, and then the components of the L-system are translated into plant organ entities via image processing and computer graphics techniques. This method can efficiently and faithfully simulate the growing process of the greenhouse tomato plant.

  1. Biofouling inhibition in MBR by Rhodococcus sp. BH4 isolated from real MBR plant.

    PubMed

    Oh, Hyun-Suk; Kim, Sang-Ryoung; Cheong, Won-Suk; Lee, Chung-Hak; Lee, Jung-Kee

    2013-12-01

    It has been reported that an indigenous quorum quenching bacterium, Rhodococcus sp. BH4, which was isolated from a real plant of membrane bioreactor (MBR) has promising potential to control biofouling in MBR. However, little is known about quorum quenching mechanisms by the strain BH4. In this study, various characteristics of strain BH4 were investigated to elucidate its behavior in more detail in the mixed liquor of MBR. The N-acyl homoserine lactone hydrolase (AHL-lactonase) gene of strain BH4 showed a high degree of identity to qsdA in Rhodococcus erythropolis W2. The LC-ESI-MS analysis of the degradation product by strain BH4 confirmed that it inactivated AHL activity by hydrolyzing the lactone bond of AHL. It degraded a wide range of N-acyl homoserine lactones (AHLs), but there was a large difference in the degradation rate of each AHL compared to other reported AHL-lactonase-producing strains belonging to Rhodococcus genus. Its quorum quenching activity was confirmed not only in the Luria-Bertani medium, but also in the synthetic wastewater. Furthermore, the amount of strain BH4 encapsulated in the vessel as well as the material of the vessel substantially affected the quorum quenching activity of strain BH4, which provides useful information, particularly for the biofouling control in a real MBR plant from an engineering point of view.

  2. The end of cheap uranium.

    PubMed

    Dittmar, Michael

    2013-09-01

    Historic data from many countries demonstrate that on average no more than 50-70% of the uranium in a deposit could be mined. An analysis of more recent data from Canada and Australia leads to a mining model with an average deposit extraction lifetime of 10±2 years. This simple model provides an accurate description of the extractable amount of uranium for the recent mining operations. Using this model for all larger existing and planned uranium mines up to 2030, a global uranium mining peak of at most 58±4 ktons around the year 2015 is obtained. Thereafter we predict that uranium mine production will decline to at most 54±5 ktons by 2025 and, with the decline steepening, to at most 41±5 ktons around 2030. This amount will not be sufficient to fuel the existing and planned nuclear power plants during the next 10-20 years. In fact, we find that it will be difficult to avoid supply shortages even under a slow 1%/year worldwide nuclear energy phase-out scenario up to 2025. We thus suggest that a worldwide nuclear energy phase-out is in order. If such a slow global phase-out is not voluntarily effected, the end of the present cheap uranium supply situation will be unavoidable. The result will be that some countries will simply be unable to afford sufficient uranium fuel at that point, which implies involuntary and perhaps chaotic nuclear phase-outs in those countries involving brownouts, blackouts, and worse.

  3. PRODUCTION OF URANIUM MONOCARBIDE

    DOEpatents

    Powers, R.M.

    1962-07-24

    A method of making essentially stoichiometric uranium monocarbide by pelletizing a mixture of uranium tetrafluoride, silicon, and carbon and reacting the mixture at a temperature of approximately 1500 to 1700 deg C until the reaction goes to completion, forming uranium monocarbide powder and volatile silicon tetrafluoride, is described. The powder is then melted to produce uranium monocarbide in massive form. (AEC)

  4. PRODUCTION OF URANIUM TETRACHLORIDE

    DOEpatents

    Calkins, V.P.

    1958-12-16

    A process is descrlbed for the production of uranium tetrachloride by contacting uranlum values such as uranium hexafluoride, uranlum tetrafluoride, or uranium oxides with either aluminum chloride, boron chloride, or sodium alumlnum chloride under substantially anhydrous condltlons at such a temperature and pressure that the chlorldes are maintained in the molten form and until the uranium values are completely converted to uranlum tetrachloride.

  5. Y-12 Uranium Exposure Study

    SciTech Connect

    Eckerman, K.F.; Kerr, G.D.

    1999-08-05

    Following the recent restart of operations at the Y-12 Plant, the Radiological Control Organization (RCO) observed that the enriched uranium exposures appeared to involve insoluble rather than soluble uranium that presumably characterized most earlier Y-12 operations. These observations necessitated changes in the bioassay program, particularly the need for routine fecal sampling. In addition, it was not reasonable to interpret the bioassay data using metabolic parameter values established during earlier Y-12 operations. Thus, the recent urinary and fecal bioassay data were interpreted using the default guidance in Publication 54 of the International Commission on Radiological Protection (ICRP); that is, inhalation of Class Y uranium with an activity median aerodynamic diameter (AMAD) of 1 {micro}m. Faced with apparently new workplace conditions, these actions were appropriate and ensured a cautionary approach to worker protection. As additional bioassay data were accumulated, it became apparent that the data were not consistent with Publication 54. Therefore, this study was undertaken to examine the situation.

  6. URANIUM EXTRACTION

    DOEpatents

    Harrington, C.D.; Opie, J.V.

    1958-07-01

    The recovery of uranium values from uranium ore such as pitchblende is described. The ore is first dissolved in nitric acid, and a water soluble nitrate is added as a salting out agent. The resulting feed solution is then contacted with diethyl ether, whereby the bulk of the uranyl nitrate and a portion of the impurities are taken up by the ether. This acid ether extract is then separated from the aqueous raffinate, and contacted with water causing back extractioa of the uranyl nitrate and impurities into the water to form a crude liquor. After separation from the ether extract, this crude liquor is heated to about 118 deg C to obtain molten uranyl nitrate hexahydratc. After being slightly cooled the uranyl nitrate hexahydrate is contacted with acid free diethyl ether whereby the bulk of the uranyl nitrate is dissolved into the ethcr to form a neutral ether solution while most of the impurities remain in the aqueous waste. After separation from the aqueous waste, the resultant ether solution is washed with about l0% of its volume of water to free it of any dissolved impurities and is then contacted with at least one half its volume of water whereby the uranyl nitrate is extracted into the water to form an aqueous product solution.

  7. Modelling the behaviour of uranium-series radionuclides in soils and plants taking into account seasonal variations in soil hydrology.

    PubMed

    Pérez-Sánchez, D; Thorne, M C

    2014-05-01

    In a previous paper, a mathematical model for the behaviour of (79)Se in soils and plants was described. Subsequently, a review has been published relating to the behaviour of (238)U-series radionuclides in soils and plants. Here, we bring together those two strands of work to describe a new mathematical model of the behaviour of (238)U-series radionuclides entering soils in solution and their uptake by plants. Initial studies with the model that are reported here demonstrate that it is a powerful tool for exploring the behaviour of this decay chain or subcomponents of it in soil-plant systems under different hydrological regimes. In particular, it permits studies of the degree to which secular equilibrium assumptions are appropriate when modelling this decay chain. Further studies will be undertaken and reported separately examining sensitivities of model results to input parameter values and also applying the model to sites contaminated with (238)U-series radionuclides. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. [Determination of uranium in spinach].

    PubMed

    Kishi, Eri; Yutani, Aiko; Ozaki, Asako; Shinya, Masanao; Katahira, Kenshi; Ooshima, Tomoko; Shimizu, Mitsuru

    2013-01-01

    After the severe accident at the Fukushima-1 Nuclear Power Plant in March 2011, radioactive contamination of food has become a matter of serious concern in Japan. There is considerable information about radioactive iodine and cesium, but little is known about uranium contamination. We determined uranium content in spinach by the Japanese official method (Manual on Radiation Measurement of Food in Emergency Situations). In the preliminary study, we confirmed that the use of a microwave digestion system for preparing the test solution of spinach could shorten the testing time and give acceptable results. The manual recommends the use of two elements (Tl and Bi) as internal standards for measurement of uranium by ICP-MS. We found that Tl was more suitable than Bi to quantify trace amounts of uranium in spinach. However, it was necessary to determine Tl or Bi concentrations in the sample before analysis, since some samples of spinach contained significant amounts of these elements. The uranium contents of 9 spinach samples bought in April and May 2011 were less than 10 μg/kg, which are very low compared to the provisional regulatory limit in Japan.

  9. 15. DETAILED VIEW OF ENRICHED URANIUM STORAGE TANK. THE ADDITION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. DETAILED VIEW OF ENRICHED URANIUM STORAGE TANK. THE ADDITION OF THE GLASS RINGS SHOWN AT THE TOP OF THE TANK HELPS PREVENT THE URANIUM FROM REACHING CRITICALITY LIMITS. (4/12/62) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

  10. DECONTAMINATION OF URANIUM

    DOEpatents

    Feder, H.M.; Chellew, N.R.

    1958-02-01

    This patent deals with the separation of rare earth and other fission products from neutron bombarded uranium. This is accomplished by melting the uranium in contact with either thorium oxide, maguesium oxide, alumnum oxide, beryllium oxide, or uranium dioxide. The melting is preferably carried out at from 1150 deg to 1400 deg C in an inert atmosphere, such as argon or helium. During this treatment a scale of uranium dioxide forms on the uranium whtch contains most of the fission products.

  11. Real-Time PCR Quantification of Chloroplast DNA Supports DNA Barcoding of Plant Species.

    PubMed

    Kikkawa, Hitomi S; Tsuge, Kouichiro; Sugita, Ritsuko

    2016-03-01

    Species identification from extracted DNA is sometimes needed for botanical samples. DNA quantification is required for an accurate and effective examination. If a quantitative assay provides unreliable estimates, a higher quantity of DNA than the estimated amount may be used in additional analyses to avoid failure to analyze samples from which extracting DNA is difficult. Compared with conventional methods, real-time quantitative PCR (qPCR) requires a low amount of DNA and enables quantification of dilute DNA solutions accurately. The aim of this study was to develop a qPCR assay for quantification of chloroplast DNA from taxonomically diverse plant species. An absolute quantification method was developed using primers targeting the ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) gene using SYBR Green I-based qPCR. The calibration curve was generated using the PCR amplicon as the template. DNA extracts from representatives of 13 plant families common in Japan. This demonstrates that qPCR analysis is an effective method for quantification of DNA from plant samples. The results of qPCR assist in the decision-making will determine the success or failure of DNA analysis, indicating the possibility of optimization of the procedure for downstream reactions.

  12. Uzbekistan unveiled. [Uranium production to commence

    SciTech Connect

    Mazurkevich, A.P.

    1993-05-01

    Through centuries of revolution, war and strife, the people of Uzbekistan have built a reputation as skilled and tenacious merchants. Since antiquity, when the Silk Road from China turned toward Europe at Smarakand, they have been master traders of such valuable commodities as cotton, fruits, vegetables, spices and gold. Now, they're about to introduce another of their specialties to the world: Uranium. Uranium mining in the country is controlled by a new, independent company, the Kizilkumredmetzoloto, parent of the Navoi Mining Metallurgy Combine [NMMC]. Established in 1958 at the height of the Cold War, when uranium mining for military stockpiles got started in earnest, Navoi was wholly owned by the USSR's Ministry of Medium Machine Building. Up until 1991, virtually all of Navoi's uranium production, strictly in the form of uranium concentrates, was used for either military purposes or for nuclear power plants within the former Soviet Union. The republic exerted no control over the final destination of its uranium. All production and operating decisions for Navoi's mines were dictated by the Soviet Union's Ministry of Atomic Power Industry [MAPI], which developed annual quotas for uranium production in each republic of the country. Uranium from the republics was sold to Techsnabexport [Tenex], the distribution and marketing arm of MAPI. Exports to other countries were handled strictly by Tenex.

  13. URANIUM DECONTAMINATION

    DOEpatents

    Buckingham, J.S.; Carroll, J.L.

    1959-12-22

    A process is described for reducing the extractability of ruthenium, zirconium, and niobium values into hexone contained in an aqueous nitric acid uranium-containing solution. The solution is made acid-deficient, heated to between 55 and 70 deg C, and at that temperature a water-soluble inorganic thiosulfate is added. By this, a precipitate is formed which carries the bulk of the ruthenium, and the remainder of the ruthenium as well as the zirconium and niobium are converted to a hexone-nonextractable form. The rutheniumcontaining precipitate can either be removed from the solu tion or it can be dissolved as a hexone-non-extractable compound by the addition of sodium dichromate prior to hexone extraction.

  14. Transfer of Plutonium-Uranium Extraction Plant and N Reactor irradiated fuel for storage at the 105-KE and 105-KW fuel storage basins, Hanford Site, Richland Washington

    SciTech Connect

    1995-07-01

    The U.S. Department of Energy (DOE) needs to remove irradiated fuel from the Plutonium-Uranium Extraction (PUREX) Plant and N Reactor at the Hanford Site, Richland, Washington, to stabilize the facilities in preparation for decontamination and decommissioning (D&D) and to reduce the cost of maintaining the facilities prior to D&D. DOE is proposing to transfer approximately 3.9 metric tons (4.3 short tons) of unprocessed irradiated fuel, by rail, from the PUREX Plant in the 200 East Area and the 105 N Reactor (N Reactor) fuel storage basin in the 100 N Area, to the 105-KE and 105-KW fuel storage basins (K Basins) in the 100 K Area. The fuel would be placed in storage at the K Basins, along with fuel presently stored, and would be dispositioned in the same manner as the other existing irradiated fuel inventory stored in the K Basins. The fuel transfer to the K Basins would consolidate storage of fuels irradiated at N Reactor and the Single Pass Reactors. Approximately 2.9 metric tons (3.2 short tons) of single-pass production reactor, aluminum clad (AC) irradiated fuel in four fuel baskets have been placed into four overpack buckets and stored in the PUREX Plant canyon storage basin to await shipment. In addition, about 0.5 metric tons (0.6 short tons) of zircaloy clad (ZC) and a few AC irradiated fuel elements have been recovered from the PUREX dissolver cell floors, placed in wet fuel canisters, and stored on the canyon deck. A small quantity of ZC fuel, in the form of fuel fragments and chips, is suspected to be in the sludge at the bottom of N Reactor`s fuel storage basin. As part of the required stabilization activities at N Reactor, this sludge would be removed from the basin and any identifiable pieces of fuel elements would be recovered, placed in open canisters, and stored in lead lined casks in the storage basin to await shipment. A maximum of 0.5 metric tons (0.6 short tons) of fuel pieces is expected to be recovered.

  15. Uranium industry annual 1994

    SciTech Connect

    1995-07-05

    The Uranium Industry Annual 1994 (UIA 1994) provides current statistical data on the US uranium industry`s activities relating to uranium raw materials and uranium marketing during that survey year. The UIA 1994 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. It contains data for the 10-year period 1985 through 1994 as collected on the Form EIA-858, ``Uranium Industry Annual Survey.`` Data collected on the ``Uranium Industry Annual Survey`` (UIAS) provide a comprehensive statistical characterization of the industry`s activities for the survey year and also include some information about industry`s plans and commitments for the near-term future. Where aggregate data are presented in the UIA 1994, care has been taken to protect the confidentiality of company-specific information while still conveying accurate and complete statistical data. A feature article, ``Comparison of Uranium Mill Tailings Reclamation in the United States and Canada,`` is included in the UIA 1994. Data on uranium raw materials activities including exploration activities and expenditures, EIA-estimated resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities, including purchases of uranium and enrichment services, and uranium inventories, enrichment feed deliveries (actual and projected), and unfilled market requirements are shown in Chapter 2.

  16. Uranium industry annual 1998

    SciTech Connect

    1999-04-22

    The Uranium Industry Annual 1998 (UIA 1998) provides current statistical data on the US uranium industry`s activities relating to uranium raw materials and uranium marketing. It contains data for the period 1989 through 2008 as collected on the Form EIA-858, ``Uranium Industry Annual Survey.`` Data provides a comprehensive statistical characterization of the industry`s activities for the survey year and also include some information about industry`s plans and commitments for the near-term future. Data on uranium raw materials activities for 1989 through 1998, including exploration activities and expenditures, EIA-estimated reserves, mine production of uranium, production of uranium concentrate, and industry employment, are presented in Chapter 1. Data on uranium marketing activities for 1994 through 2008, including purchases of uranium and enrichment services, enrichment feed deliveries, uranium fuel assemblies, filled and unfilled market requirements, and uranium inventories, are shown in Chapter 2. The methodology used in the 1998 survey, including data edit and analysis, is described in Appendix A. The methodologies for estimation of resources and reserves are described in Appendix B. A list of respondents to the ``Uranium Industry Annual Survey`` is provided in Appendix C. The Form EIA-858 ``Uranium Industry Annual Survey`` is shown in Appendix D. For the readers convenience, metric versions of selected tables from Chapters 1 and 2 are presented in Appendix E along with the standard conversion factors used. A glossary of technical terms is at the end of the report. 24 figs., 56 tabs.

  17. Uranium Exposures in a Community near a Uranium Processing Facility: Relationship with Hypertension and Hematologic Markers

    PubMed Central

    Wagner, Sara E.; Burch, James B.; Bottai, Matteo; Pinney, Susan M.; Puett, Robin; Porter, Dwayne; Vena, John E.; Hébert, James R.

    2010-01-01

    Background Environmental uranium exposure originating as a byproduct of uranium processing can impact human health. The Fernald Feed Materials Production Center functioned as a uranium processing facility from 1951 to 1989, and potential health effects among residents living near this plant were investigated via the Fernald Medical Monitoring Program (FMMP). Methods Data from 8,216 adult FMMP participants were used to test the hypothesis that elevated uranium exposure was associated with indicators of hypertension or changes in hematologic parameters at entry into the program. A cumulative uranium exposure estimate, developed by FMMP investigators, was used to classify exposure. Systolic and diastolic blood pressure and physician diagnoses were used to assess hypertension; and red blood cells, platelets, and white blood cell differential counts were used to characterize hematology. The relationship between uranium exposure and hypertension or hematologic parameters was evaluated using generalized linear models and quantile regression for continuous outcomes, and logistic regression or ordinal logistic regression for categorical outcomes, after adjustment for potential confounding factors. Results Of 8,216 adult FMMP participants 4,187 (51%) had low cumulative uranium exposure, 1,273 (15%) had moderate exposure, and 2,756 (34%) were in the high (>0.50 Sievert) cumulative lifetime uranium exposure category. Participants with elevated uranium exposure had decreased white blood cell and lymphocyte counts and increased eosinophil counts. Female participants with higher uranium exposures had elevated systolic blood pressure compared to women with lower exposures. However, no exposure-related changes were observed in diastolic blood pressure or hypertension diagnoses among female or male participants. Conclusions Results from this investigation suggest that residents in the vicinity of the Fernald plant with elevated exposure to uranium primarily via inhalation exhibited

  18. The International Science and Politics of Depleted Uranium (Briefing charts)

    DTIC Science & Technology

    2010-11-01

    Cabrera 3 mrem/y These results for non- carcinogenic risks indicate that there are no adverse impacts expected due to chemical exposure to DU. Iraq...on the health effects of uranium (to include depleted uranium) • The dose makes the poison • Uranium is a weak carcinogen • There are safe levels of...blatant lies”* “ Tobacco industry hired- gun”* * Haleakala Times – December 4th, 2007 What I Actually Do … Science Real The Press • Rediscovers the issue

  19. Process for electroslag refining of uranium and uranium alloys

    DOEpatents

    Lewis, P.S. Jr.; Agee, W.A.; Bullock, J.S. IV; Condon, J.B.

    1975-07-22

    A process is described for electroslag refining of uranium and uranium alloys wherein molten uranium and uranium alloys are melted in a molten layer of a fluoride slag containing up to about 8 weight percent calcium metal. The calcium metal reduces oxides in the uranium and uranium alloys to provide them with an oxygen content of less than 100 parts per million. (auth)

  20. Field-based species identification of closely-related plants using real-time nanopore sequencing.

    PubMed

    Parker, Joe; Helmstetter, Andrew J; Devey, Dion; Wilkinson, Tim; Papadopulos, Alexander S T

    2017-08-21

    Advances in DNA sequencing and informatics have revolutionised biology over the past four decades, but technological limitations have left many applications unexplored. Recently, portable, real-time, nanopore sequencing (RTnS) has become available. This offers opportunities to rapidly collect and analyse genomic data anywhere. However, generation of datasets from large, complex genomes has been constrained to laboratories. The portability and long DNA sequences of RTnS offer great potential for field-based species identification, but the feasibility and accuracy of these technologies for this purpose have not been assessed. Here, we show that a field-based RTnS analysis of closely-related plant species (Arabidopsis spp.) has many advantages over laboratory-based high-throughput sequencing (HTS) methods for species level identification and phylogenomics. Samples were collected and sequenced in a single day by RTnS using a portable, "al fresco" laboratory. Our analyses demonstrate that correctly identifying unknown reads from matches to a reference database with RTnS reads enables rapid and confident species identification. Individually annotated RTnS reads can be used to infer the evolutionary relationships of A. thaliana. Furthermore, hybrid genome assembly with RTnS and HTS reads substantially improved upon a genome assembled from HTS reads alone. Field-based RTnS makes real-time, rapid specimen identification and genome wide analyses possible.

  1. The ultimate disposition of depleted uranium

    SciTech Connect

    Lemons, T.R.

    1991-12-31

    Depleted uranium (DU) is produced as a by-product of the uranium enrichment process. Over 340,000 MTU of DU in the form of UF{sub 6} have been accumulated at the US government gaseous diffusion plants and the stockpile continues to grow. An overview of issues and objectives associated with the inventory management and the ultimate disposition of this material is presented.

  2. PRODUCTION OF PURIFIED URANIUM

    DOEpatents

    Burris, L. Jr.; Knighton, J.B.; Feder, H.M.

    1960-01-26

    A pyrometallurgical method for processing nuclear reactor fuel elements containing uranium and fission products and for reducing uranium compound; to metallic uranium is reported. If the material proccssed is essentially metallic uranium, it is dissolved in zinc, the sulution is cooled to crystallize UZn/sub 9/ , and the UZn/sub 9/ is distilled to obtain uranium free of fission products. If the material processed is a uranium compound, the sollvent is an alloy of zinc and magnesium and the remaining steps are the same.

  3. URANIUM RECOVERY PROCESS

    DOEpatents

    Bailes, R.H.; Long, R.S.; Olson, R.S.; Kerlinger, H.O.

    1959-02-10

    A method is described for recovering uranium values from uranium bearing phosphate solutions such as are encountered in the manufacture of phosphate fertilizers. The solution is first treated with a reducing agent to obtain all the uranium in the tetravalent state. Following this reduction, the solution is treated to co-precipitate the rcduced uranium as a fluoride, together with other insoluble fluorides, thereby accomplishing a substantially complete recovery of even trace amounts of uranium from the phosphate solution. This precipitate usually takes the form of a complex fluoride precipitate, and after appropriate pre-treatment, the uranium fluorides are leached from this precipitate and rccovered from the leach solution.

  4. Experimental verification of a real-time power curve for downregulated offshore wind power plants

    NASA Astrophysics Data System (ADS)

    Giebel, Gregor; Göcmen Bozkurt, Tuhfe; Sørensen, Poul; Rajczyk Skjelmose, Mads; Runge Kristoffersen, Jesper

    2015-04-01

    Wind farm scale experiments with wakes under downregulation have been initiated in Horns Rev wind farm in the frame of the PossPOW project (see posspow.dtu.dk). The experiments will be compared with the results of the calibrated GCLarsen wake model for real-time which is used not only to obtain real-time power curve but also to estimate the available power in wind farm level. Available (or Possible) Power is the power that a down-regulated (or curtailed) turbine or a wind power plant would produce if it were to operate in normal operational conditions and it is becoming more of particular interest due to increasing number of curtailment periods. Currently, the Transmission System Operators (TSOs) have no real way to determine exactly the available power of a down-regulated wind farm and the PossPOW project is addressing that need. What makes available power calculation interesting at the wind farm level is the change in the wake characteristics for different operational states. Even though the single turbine level available power is easily estimated, the sum of those signals from all turbines in a wind farm overestimates the power since the wake losses significantly decrease during curtailment. In order to calculate that effect, the turbine wind speed is estimated real-time from the produced power, the pitch angle and the rotor speed using a proximate Cp curve. A real-time wake estimation of normal operation is then performed and advected to the next downstream turbine, and so on until the entire wind farm is calculated. The estimation of the rotor effective wind speed, the parameterization of the GCLarsen wake model for real-time use (i.e., 1-sec data from Horns Rev and Thanet) and the details of the advection are the topic can be found in Göcmen et al. [1] Here we plan to describe the experiments using the Horns Rev wind farm and hopefully present the first validation results. Assuming similarity of the wind speeds between neighbouring rows of turbines, the

  5. Safeguards Guidance Document for Designers of Commercial Nuclear Facilities: International Nuclear Safeguards Requirements and Practices For Uranium Enrichment Plants

    SciTech Connect

    Robert Bean; Casey Durst

    2009-10-01

    This report is the second in a series of guidelines on international safeguards requirements and practices, prepared expressly for the designers of nuclear facilities. The first document in this series is the description of generic international nuclear safeguards requirements pertaining to all types of facilities. These requirements should be understood and considered at the earliest stages of facility design as part of a new process called “Safeguards-by-Design.” This will help eliminate the costly retrofit of facilities that has occurred in the past to accommodate nuclear safeguards verification activities. The following summarizes the requirements for international nuclear safeguards implementation at enrichment plants, prepared under the Safeguards by Design project, and funded by the U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA), Office of NA-243. The purpose of this is to provide designers of nuclear facilities around the world with a simplified set of design requirements and the most common practices for meeting them. The foundation for these requirements is the international safeguards agreement between the country and the International Atomic Energy Agency (IAEA), pursuant to the Treaty on the Non-proliferation of Nuclear Weapons (NPT). Relevant safeguards requirements are also cited from the Safeguards Criteria for inspecting enrichment plants, found in the IAEA Safeguards Manual, Part SMC-8. IAEA definitions and terms are based on the IAEA Safeguards Glossary, published in 2002. The most current specification for safeguards measurement accuracy is found in the IAEA document STR-327, “International Target Values 2000 for Measurement Uncertainties in Safeguarding Nuclear Materials,” published in 2001. For this guide to be easier for the designer to use, the requirements have been restated in plainer language per expert interpretation using the source documents noted. The safeguards agreement is fundamentally a

  6. Uptake of radium-226 from uranium mill tailing by C-3 and C-4 plants and implications for transport of radium-226 and radon-222 into the disposal-site environment

    SciTech Connect

    MacDonell, M.M.

    1986-01-01

    Radium-226 entry into plants grown on uranium mill tailings at pH 6.5 appears to be governed primarily by movement of tailings solution into the plant. The lower transpiration ratios of C-4 photosynthetic plants as compared to C-3 plants result in lower tissue concentrations of radium-225. In each case, the distribution of radium-226 within the plants studied: corn (C-4), dwarf sunflower (C-3), tall fescue grass (C-3), and four species of Panicum (two C-3 and two C-4) exhibited an acropetal gradient, decreasing from the roots where the concentrations are relatively high to the apex of the plant. Tissue concentrations of Ra-226 decreased over time, attributable to increases in biomass while total Ra-226 levels remain constant. Release of radon from vegetated tailings was found to be directly related to the total leaf area of the plant following introduction into the plant of tailings solution. Thus, the plant pathway is shown to be an important mechanism for the transport of radium-226 and radon-222 from mill tailings into the environment. Current tailings disposal site reclamation efforts should consider the effects of the photosynthetic nature of the vegetation species and its total leaf area to reduce the potential for introduction of these elements into the site environment.

  7. Ecotechnological approach for consolidation of uranium tailings.

    PubMed

    Soni, Prafulla; Singh, Lal

    2011-07-01

    Present study has been undertaken to consolidate radioactivity in uranium mill tailings at Jaduguda, Jharkhand, India.Tailings that remain after processing of ore are released in tailing ponds specially designed for the purpose. The degraded tailing ponds have been capped with 30 cm. thick soil cover. For cosolidation of radioactivity in the tailings firstly the selected plant species should not have any socioeconomic relevance in that area and secondly, uptake of uranium by selected plants has to be low to avoid its dissemination in any form in environment. Seven native plant species of forestry origin were used for experimental trials. Above ground growth has been measured for two years under ex- situ and in- situ conditions. Distribution and concentration of uranium have been evaluated in tailing pond soil as well as tailings. Uranium uptake by plants has been evaluated and discussed in this paper. The highest concentration of uranium has been found in the order as: in tailings > soil cover on tailings > roots of selected plant species > shoots of all the selected species. These results show that among seven species tried Jatropha gossypifolia and Furcraea foetida have lowest uptake (below detectable limit), while Saccharum spontaneum and Pogostemon benghalense have comparatively higher uptake among the studied species.

  8. Removal of uranium from uranium-contaminated soils -- Phase 1: Bench-scale testing. Uranium in Soils Integrated Demonstration

    SciTech Connect

    Francis, C. W.

    1993-09-01

    To address the management of uranium-contaminated soils at Fernald and other DOE sites, the DOE Office of Technology Development formed the Uranium in Soils Integrated Demonstration (USID) program. The USID has five major tasks. These include the development and demonstration of technologies that are able to (1) characterize the uranium in soil, (2) decontaminate or remove uranium from the soil, (3) treat the soil and dispose of any waste, (4) establish performance assessments, and (5) meet necessary state and federal regulations. This report deals with soil decontamination or removal of uranium from contaminated soils. The report was compiled by the USID task group that addresses soil decontamination; includes data from projects under the management of four DOE facilities [Argonne National Laboratory (ANL), Los Alamos National Laboratory (LANL), Oak Ridge National Laboratory (ORNL), and the Savannah River Plant (SRP)]; and consists of four separate reports written by staff at these facilities. The fundamental goal of the soil decontamination task group has been the selective extraction/leaching or removal of uranium from soil faster, cheaper, and safer than current conventional technologies. The objective is to selectively remove uranium from soil without seriously degrading the soil`s physicochemical characteristics or generating waste forms that are difficult to manage and/or dispose of. Emphasis in research was placed more strongly on chemical extraction techniques than physical extraction techniques.

  9. METHOD FOR PURIFYING URANIUM

    DOEpatents

    Knighton, J.B.; Feder, H.M.

    1960-04-26

    A process is given for purifying a uranium-base nuclear material. The nuclear material is dissolved in zinc or a zinc-magnesium alloy and the concentration of magnesium is increased until uranium precipitates.

  10. NICKEL COATED URANIUM ARTICLE

    DOEpatents

    Gray, A.G.

    1958-10-01

    Nickel coatings on uranium and various methods of obtaining such coatings are described. Specifically disclosed are such nickel or nickel alloy layers as barriers between uranium and aluminum- silicon, chromium, or copper coatings.

  11. PROCESS OF PURIFYING URANIUM

    DOEpatents

    Seaborg, G.T.; Orlemann, E.F.; Jensen, L.H.

    1958-12-23

    A method of obtaining substantially pure uranium from a uranium composition contaminated with light element impurities such as sodium, magnesium, beryllium, and the like is described. An acidic aqueous solution containing tetravalent uranium is treated with a soluble molybdate to form insoluble uranous molybdate which is removed. This material after washing is dissolved in concentrated nitric acid to obtaln a uranyl nitrate solution from which highly purified uranium is obtained by extraction with ether.

  12. Uranium industry annual 1995

    SciTech Connect

    1996-05-01

    The Uranium Industry Annual 1995 (UIA 1995) provides current statistical data on the U.S. uranium industry`s activities relating to uranium raw materials and uranium marketing. The UIA 1995 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. It contains data for the period 1986 through 2005 as collected on the Form EIA-858, ``Uranium Industry Annual Survey``. Data collected on the ``Uranium Industry Annual Survey`` provide a comprehensive statistical characterization of the industry`s plans and commitments for the near-term future. Where aggregate data are presented in the UIA 1995, care has been taken to protect the confidentiality of company-specific information while still conveying accurate and complete statistical data. Data on uranium raw materials activities for 1986 through 1995 including exploration activities and expenditures, EIA-estimated reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities for 1994 through 2005, including purchases of uranium and enrichment services, enrichment feed deliveries, uranium fuel assemblies, filled and unfilled market requirements, uranium imports and exports, and uranium inventories are shown in Chapter 2. The methodology used in the 1995 survey, including data edit and analysis, is described in Appendix A. The methodologies for estimation of resources and reserves are described in Appendix B. A list of respondents to the ``Uranium Industry Annual Survey`` is provided in Appendix C. For the reader`s convenience, metric versions of selected tables from Chapters 1 and 2 are presented in Appendix D along with the standard conversion factors used. A glossary of technical terms is at the end of the report. 14 figs., 56 tabs.

  13. PREPARATION OF URANIUM HEXAFLUORIDE

    DOEpatents

    Lawroski, S.; Jonke, A.A.; Steunenberg, R.K.

    1959-10-01

    A process is described for preparing uranium hexafluoride from carbonate- leach uranium ore concentrate. The briquetted, crushed, and screened concentrate is reacted with hydrogen fluoride in a fluidized bed, and the uranium tetrafluoride formed is mixed with a solid diluent, such as calcium fluoride. This mixture is fluorinated with fluorine and an inert diluent gas, also in a fluidized bed, and the uranium hexafluoride obtained is finally purified by fractional distillation.

  14. Uranium Immobilization in Wetland Soils

    NASA Astrophysics Data System (ADS)

    Jaffe, Peter R.; Koster van Groos, Paul G.; Li, Dien; Chang, Hyun-Shik; Seaman, John C.; Kaplan, Daniel I.; Peacock, Aaron D.; Scheckel, Kirk

    2014-05-01

    In wetlands, which are a major feature at the groundwater-surface water interface, plants deliver oxygen to the subsurface to keep root tissue aerobic. Some of this oxygen leaches into the rhizosphere where it will oxidize iron that typically precipitates on or near roots. Furthermore, plans provide carbon via root exudates and turnover, which in the presence of the iron oxides drives the activity of heterotrophic iron reducers in wetland soils. Oxidized iron is an important electron acceptor for many microbially-driven transformations, which can affect the fate and transport of several pollutants. It has been shown that heterotrophic iron reducing organisms, such as Geobacter sp., can reduce water soluble U(VI) to insoluble U(IV). The goal of this study was to determine if and how iron cycling in the wetland rhizosphere affects uranium dynamics. For this purpose, we operated a series of small-scale wetland mesocosms in a greenhouse to simulate the discharge of uranium-contaminated groundwater to surface waters. The mesocosms were operated with two different Fe(II) loading rates, two plant types, and unplanted controls. The mesocosms contained zones of root exclusion to differentiate between the direct presence and absence of roots in the planted mesocosms. The mesocosms were operated for several month to get fully established, after which a U(VI) solution was fed for 80 days. The mesocosms were then sacrificed and analyzed for solid-associated chemical species, microbiological characterization, micro-X-ray florescence (µ-XRF) mapping of Fe and U on the root surface, and U speciation via X-ray Absorption Near Edge Structure (XANES). Results showed that bacterial numbers including Geobacter sp., Fe(III), as well as total uranium, were highest on roots, followed by sediments near roots, and lowest in zones without much root influence. Results from the µ-XRF mapping on root surfaces indicated a strong spatial correlation between Fe and U. This correlation was

  15. PRODUCTION OF URANIUM TETRAFLUORIDE

    DOEpatents

    Shaw, W.E.; Spenceley, R.M.; Teetzel, F.M.

    1959-08-01

    A method is presented for producing uranium tetrafluoride from the gaseous hexafluoride by feeding the hexafluoride into a high temperature zone obtained by the recombination of molecularly dissociated hydrogen. The molal ratio of hydrogen to uranium hexnfluoride is preferably about 3 to 1. Uranium tetrafluoride is obtained in a finely divided, anhydrous state.

  16. A Robust Plant RNA Isolation Method for Affymetrix Genechip® Analysis and Quantitative Real-Time RT-PCR

    USDA-ARS?s Scientific Manuscript database

    Microarray analysis and quantitative real-time RT-PCR are the major high-throughput techniques that are used to study transcript profiles. One of the major limitations in these technologies is the isolation maximum yield of highly-pure RNA from plant tissues rich in complex polysaccharides, polyphen...

  17. The chemical composition of nanoparticles formed from the oxidation of real plant emissions

    NASA Astrophysics Data System (ADS)

    Winkler, P. M.; Ortega, J.; Barsanti, K. C.; Friedli, H. R.; Smith, J. N.

    2010-12-01

    Organic vapors from biosphere emissions clearly participate in the formation of secondary organic aerosol (SOA). Thereby volatile organic compounds (VOCs) are transformed by photolytic reactions to low volatility organic compounds capable of condensing onto particles even in a size range where the strong curvature typically prevents vapor condensation by most other condensable vapors (Kelvin effect). However, the exact compounds responsible for nanoparticle formation and growth largely remain unknown. In this study we conducted chamber experiments under well-defined conditions to investigate chemical and physical properties of aerosol particles formed from oxidation products of real plant emissions. The chamber used comprises of a 10 m^3 Teflon FEP bag, operated at room temperature. Emissions from specific plants, e.g., a pine tree, can be added to the chamber and may produce aerosol particles after oxidation with ozone and/or OH. Gas chromatographs, trace gas analyzers, and aerosol sizing instruments provide a comprehensive set of instruments to analyze gas phase composition and aerosol size distribution. The chemical composition of nanoparticles at a pre-selected size is analyzed with the thermal desorption chemical ionization mass spectrometer (TDCIMS) (Smith & Rathbone, Int. J. Mass Spectrom. 274, 8 (2008)) providing positive and negative ion mass spectra with a time resolution of about 10 minutes. Here we present results from the emissions of ponderosa pine, the dominant tree species in the Rocky Mountains. These data are directly compared to measurements obtained by the TDCIMS during the BEACHON-SRM08 field campaign, which took place from 15 July - 15 August 2008 at the NCAR Manitou Forest Observatory near Woodland Park, CO. This comparison also gives insight into the ability of these chambers to simulate biogenic SOA formation.

  18. Optimization of a biotechnological multiproduct batch plant design for the manufacture of four different products: A real case scenario.

    PubMed

    Sandoval, Gabriela; Espinoza, Daniel; Figueroa, Nicolas; Asenjo, Juan A

    2017-06-01

    In this work a biotechnological multiproduct batch plant that manufactures four different recombinant proteins for human application is described in some detail. This batch plant design is then optimized with regards to the size of equipment using a mixed-integer linear programming (MILP) formulation recently developed by us in order to find a hypothetical new biotechnological batch plant based on the information of real known processes for the production of the four recombinant protein products. The real plant was divided for practical purposes into two sub-processes or facilities: a fermentation facility and a purification facility. Knowing the specific steps conforming the downstream processing of each product, size, and time factors were computed and used as parameters to solve the aforementioned MILP reformulation. New constraints were included to permit the selection of some equipment-such as centrifuges and membrane filters-in a discrete set of sizes. For equipment that can be built according to customer needs-such as reactors-the original formulation was retained. Computational results show the ability of this optimization methodology to deal with real data giving reliable solutions for a multi-product batch plant composed of 44 unit operations in a relatively small amount of time showing that in the case studied it is possible to save up to a 66% of the capital investment in equipment given the cost data used. Biotechnol. Bioeng. 2017;114: 1252-1263. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. PROCESS OF RECOVERING URANIUM

    DOEpatents

    Carter, J.M.; Larson, C.E.

    1958-10-01

    A process is presented for recovering uranium values from calutron deposits. The process consists in treating such deposits to produce an oxidlzed acidic solution containing uranium together with the following imparities: Cu, Fe, Cr, Ni, Mn, Zn. The uranium is recovered from such an impurity-bearing solution by adjusting the pH of the solution to the range 1.5 to 3.0 and then treating the solution with hydrogen peroxide. This results in the precipitation of uranium peroxide which is substantially free of the metal impurities in the solution. The peroxide precipitate is then separated from the solution, washed, and calcined to produce uranium trioxide.

  20. URANIUM SEPARATION PROCESS

    DOEpatents

    Hyde, E.K.; Katzin, L.I.; Wolf, M.J.

    1959-07-14

    The separation of uranium from a mixture of uranium and thorium by organic solvent extraction from an aqueous solution is described. The uranium is separrted from an aqueous mixture of uranium and thorium nitrates 3 N in nitric acid and containing salting out agents such as ammonium nitrate, so as to bring ihe total nitrate ion concentration to a maximum of about 8 N by contacting the mixture with an immiscible aliphatic oxygen containing organic solvent such as diethyl carbinol, hexone, n-amyl acetate and the like. The uranium values may be recovered from the organic phase by back extraction with water.

  1. URANIUM RECOVERY PROCESS

    DOEpatents

    Yeager, J.H.

    1958-08-12

    In the prior art processing of uranium ores, the ore is flrst digested with nitric acid and filtered, and the uranium values are then extracted tom the filtrate by contacting with an organic solvent. The insoluble residue has been processed separately in order to recover any uranium which it might contain. The improvement consists in contacting a slurry, composed of both solution and residue, with the organic solvent prior to filtration. Tbe result is that uranium values contained in the residue are extracted along with the uranium values contained th the solution in one step.

  2. PRODUCTION OF URANIUM

    DOEpatents

    Spedding, F.H.; Wilhelm, H.A.; Keller, W.H.

    1958-04-15

    The production of uranium metal by the reduction of uranium tetrafluoride is described. Massive uranium metal of high purily is produced by reacting uranium tetrafluoride with 2 to 20% stoichiometric excess of magnesium at a temperature sufficient to promote the reaction and then mantaining the reaction mass in a sealed vessel at temperature in the range of 1150 to 2000 d C, under a superatomospheric pressure of magnesium for a period of time sufficient 10 allow separation of liquid uranium and liquid magnesium fluoride into separate layers.

  3. Method for converting uranium oxides to uranium metal

    DOEpatents

    Duerksen, Walter K.

    1988-01-01

    A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixture is then cooled to a temperature less than -100.degree. C. in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.

  4. Biota of uranium mill tailings near the Black Hills

    Treesearch

    Mark A. Rumble

    1982-01-01

    Reclamation" often implies the enhancement of the land as wildlife habitat or for other productive uses. However, there are situations where revegetation to stabilize erosion is the only desired goal. Uranium mining and mill sites may fall into this later category. Data pertaining to plant and animal components on revegetated uranium mill tailings was collected....

  5. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...

  6. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...

  7. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...

  8. Integrating uranium from weapons into the civil fuel cycle

    SciTech Connect

    Neff, T.L. )

    1993-01-01

    Under a recently-approved agreement, Russia will sell perhaps 500 tonnes of highly enriched uranium (HEU) recovered from its dismantled nuclear weapons to the US Department of Energy over the next twenty years. Blended with natural or depleted uranium to produce low-enriched uranium for reactor fuel, this HEU could displace power consumption in the electricity-intensive gaseous diffusion plants of the US. The sale of the HEU could be done in a way that minimizes uranium market disruptions and benefits both the US and Russia. 4 figs., 1 tab.

  9. Assessing the environmental availability of uranium in soils and sediments

    SciTech Connect

    Amonette, J.E.; Holdren, G.R. Jr.; Krupa, K.M.; Lindenmeier, C.W.

    1994-06-01

    Soils and sediments contaminated with uranium pose certain environmental and ecological risks. At low to moderate levels of contamination, the magnitude of these risks depends not only on the absolute concentrations of uranium in the material but also on the availability of the uranium to drinking water supplies, plants, or higher organisms. Rational approaches for regulating the clean-up of sites contaminated with uranium, therefore, should consider the value of assessing the environmental availability of uranium at the site before making decisions regarding remediation. The purpose of this work is to review existing approaches and procedures to determine their potential applicability for assessing the environmental availability of uranium in bulk soils or sediments. In addition to making the recommendations regarding methodology, the authors have tabulated data from the literature on the aqueous complexes of uranium and major uranium minerals, examined the possibility of predicting environmental availability of uranium based on thermodynamic solubility data, and compiled a representative list of analytical laboratories capable of performing environmental analyses of uranium in soils and sediments.

  10. Speciation of uranium in compartments of living cells.

    PubMed

    Geipel, Gerhard; Viehweger, Katrin

    2015-06-01

    Depleted uranium used as ammunition corrodes in the environment forming mineral phases and then dissolved uranium species like uranium carbonates (Schimmack et al., in Radiat Environ Biophys 46:221-227, 2007) and hydroxides. These hydroxide species were contacted with plant cells (canola). After 24 h contact time the cells were fractionated and the uranium speciation in the fraction was determined by time resolved laser-induced fluorescence spectroscopy at room temperature as well at 150 K. It could be shown that the uranium speciation in the fractions is different to that in the nutrient solution. Comparison of the emission bands with literature data allows assignment of the uranium binding forms.

  11. Welding of uranium and uranium alloys

    SciTech Connect

    Mara, G.L.; Murphy, J.L.

    1982-03-26

    The major reported work on joining uranium comes from the USA, Great Britain, France and the USSR. The driving force for producing this technology base stems from the uses of uranium as a nuclear fuel for energy production, compact structures requiring high density, projectiles, radiation shielding, and nuclear weapons. This review examines the state-of-the-art of this technology and presents current welding process and parameter information. The welding metallurgy of uranium and the influence of microstructure on mechanical properties is developed for a number of the more commonly used welding processes.

  12. Effects of real or simulated microgravity on plant cell growth and proliferation

    NASA Astrophysics Data System (ADS)

    Medina, Francisco Javier; Manzano, Ana Isabel; Herranz, Raul; Dijkstra, Camelia; Larkin, Oliver; Hill, Richard; Carnero-Díaz, Eugénie; van Loon, Jack J. W. A.; Anthony, Paul; Davey, Michael R.; Eaves, Laurence

    Experiments on seed germination and seedling growth performed in real microgravity on the International Space Station and in different facilities for simulating microgravity in Earth-based laboratories (Random Positioning Machine and Magnetic Levitation), have provided evidence that the absence of gravity (or the artificial compensation of the gravity vector) results in the uncoupling of cell growth and proliferation in root meristematic cells. These are two essential cellular functions that support plant growth and development, which are strictly coordinated under normal ground gravity conditions. Under conditions of altered gravity, we observe that cell proliferation is enhanced, whereas cell growth is reduced, according to different morphometric, cytological and immunocytochemical parameters. Since coordination of cell growth and proliferation are major features of meristematic cells, this observed uncoupling represents a major stress condition for these cells, inducing major alterations in the pattern of plant development. Moreover, the expression of the cyclin B1 gene, a regulator of the entry into mitosis and normally used as an indicator of cell proliferation, appears reduced in the smaller and more actively proliferating cells of samples grown under the conditions of our experiments. These results are compatible with an alteration of the regulation of the cell cycle, producing a shorter G2 period. Interestingly, while cyclin B1 expression is depleted in these conditions in root meristematic cells, it is enhanced in cotyledons of the same seedlings, as shown by qPCR and by the expression of the gus reporter gene. It is known that regulation of root growth (including regulation of root meristematic activity) is driven mainly by auxin, whereas cytokinin is the key hormone regulating cotyledon growth. Therefore, our results indicate a major role of auxin in the sensitivity to altered gravity of root meristematic cells. Auxin is crucial in maintaining the

  13. Uranium hexafluoride public risk

    SciTech Connect

    Fisher, D.R.; Hui, T.E.; Yurconic, M.; Johnson, J.R.

    1994-08-01

    The limiting value for uranium toxicity in a human being should be based on the concentration of uranium (U) in the kidneys. The threshold for nephrotoxicity appears to lie very near 3 {mu}g U per gram kidney tissue. There does not appear to be strong scientific support for any other improved estimate, either higher or lower than this, of the threshold for uranium nephrotoxicity in a human being. The value 3 {mu}g U per gram kidney is the concentration that results from a single intake of about 30 mg soluble uranium by inhalation (assuming the metabolism of a standard person). The concentration of uranium continues to increase in the kidneys after long-term, continuous (or chronic) exposure. After chronic intakes of soluble uranium by workers at the rate of 10 mg U per week, the concentration of uranium in the kidneys approaches and may even exceed the nephrotoxic limit of 3 {mu}g U per gram kidney tissue. Precise values of the kidney concentration depend on the biokinetic model and model parameters assumed for such a calculation. Since it is possible for the concentration of uranium in the kidneys to exceed 3 {mu}g per gram tissue at an intake rate of 10 mg U per week over long periods of time, we believe that the kidneys are protected from injury when intakes of soluble uranium at the rate of 10 mg U per week do not continue for more than two consecutive weeks. For long-term, continuous occupational exposure to low-level, soluble uranium, we recommend a reduced weekly intake limit of 5 mg uranium to prevent nephrotoxicity in workers. Our analysis shows that the nephrotoxic limit of 3 {mu}g U per gram kidney tissues is not exceeded after long-term, continuous uranium intake at the intake rate of 5 mg soluble uranium per week.

  14. Bioremediation of uranium contamination with enzymatic uranium reduction

    USGS Publications Warehouse

    Lovley, D.R.; Phillips, E.J.P.

    1992-01-01

    Enzymatic uranium reduction by Desulfovibrio desulfuricans readily removed uranium from solution in a batch system or when D. desulfuricans was separated from the bulk of the uranium-containing water by a semipermeable membrane. Uranium reduction continued at concentrations as high as 24 mM. Of a variety of potentially inhibiting anions and metals evaluated, only high concentrations of copper inhibited uranium reduction. Freeze-dried cells, stored aerobically, reduced uranium as fast as fresh cells. D. desulfuricans reduced uranium in pH 4 and pH 7.4 mine drainage waters and in uraniumcontaining groundwaters from a contaminated Department of Energy site. Enzymatic uranium reduction has several potential advantages over other bioprocessing techniques for uranium removal, the most important of which are as follows: the ability to precipitate uranium that is in the form of a uranyl carbonate complex; high capacity for uranium removal per cell; the formation of a compact, relatively pure, uranium precipitate.

  15. Estimate of the dose-increment due to outdoor exposure to gamma rays from uranium progeny deposited on the soil around a coal-fired power plant in Ajka Town, Hungary.

    PubMed

    Papp, Z; Dezsö, Z

    2003-06-01

    Brown coal unusually rich in uranium is burnt in a coal-fired power plant that lies inside the confines of a small industrial town named Ajka, Hungary, and has been operational since 1943. The 238U (226Ra) activity discharged to the atmosphere per unit electrical energy produced was about 330-400 GBq (GW y)(-1), which is 66-80 times more than that was estimated by UNSCEAR (1988) as a characteristic value for old type coal-fired power plants [5 GBq (GW y)(-1)]. The objective of this study was the experimentally established assessment of the artificial increment in the dose from external exposure to gamma rays of terrestrial radionuclides outdoors. Soil samples were collected in and near Ajka from 81 locations. The samples were investigated by Ge(Li) gamma spectrometry. Considerably elevated concentrations of uranium and its progeny have been measured in most of the samples that were collected near to the plant. Concentrations of 238U and 226Ra in the top (0-5 cm depth) layer of undisturbed soil at public areas inside town were 4.7 times higher, on average, than those in the uncontaminated deeper layers. Dose rate in air (air kerma) from external exposure to terrestrial gamma rays outdoors at a height of 1 m and effective doses were estimated from the measured activity concentrations using some relevant literature data. The estimated artificial increment in the dose rate in air was, on average, 32.8, 10.3, and 102.1 nGy h(-1) at public areas, vegetable gardens, and backyards, respectively. The mean artificial increment in the annual per caput effective dose from external exposure to terrestrial radionuclides outdoors is 21.8 microSv y(-1). The collective dose commitment per unit energy generated from outdoor exposure to the deposited uranium progeny is about 8.0-9.1 person Sv (GW y)(-1), which is 67-76 times more than that evaluated by UNSCEAR (1988) for a typical "old" coal-fired power plant [0.12 person Sv (GW y)(-1)]. Ajka is a suitable place for studying the

  16. Microbial transformation of uranium in wastes

    SciTech Connect

    Francis, A.J.; Dodge, C.J.; Gillow, J.B.; Cline, J.E.; Oak Ridge Y-12 Plant, TN )

    1989-01-01

    Contamination of soils, water, and sediments by radionuclides and toxic metals from the disposal of uranium processing wastes is a major national concern. Although much is known about the physico- chemical aspects of U, we have little information on the effects of aerobic and anaerobic microbial activities on the mobilization or immobilization of U and other toxic metals in mixed wastes. In order to understand the mechanisms of microbial transformations of uranium, we examined a contaminated pond sediment and a sludge sample from the uranium processing facility at Y-12 Plant, Oak Ridge, TN. The uranium concentration in the sediment and sludge samples was 923 and 3080 ug/g dry wt, respectively. In addition to U, the sediment and sludge samples contained high levels of toxic metals such as Cd, Cr, Cu, Hg, Pb, Ni, and Zn. The association of uranium with the various mineral fractions of the sediment and sludge was determined by selective chemical extraction techniques. Uranium was associated to varying degrees with the exchangeable carbonate, iron oxide, organic, and inert fractions in both samples. Initial results in samples amended with carbon and nitrogen indicate immobilization of U due to enhanced indigenous microbial activity under anaerobic conditions. 23 refs., 4 figs., 5 tabs.

  17. Uranium purchases report 1992

    SciTech Connect

    Not Available

    1993-08-19

    Data reported by domestic nuclear utility companies in their responses to the 1991 and 1992 ``Uranium Industry Annual Survey,`` Form EIA-858, Schedule B ``Uranium Marketing Activities,are provided in response to the requirements in the Energy Policy Act 1992. Data on utility uranium purchases and imports are shown on Table 1. Utility enrichment feed deliveries and secondary market acquisitions of uranium equivalent of US DOE separative work units are shown on Table 2. Appendix A contains a listing of firms that sold uranium to US utilities during 1992 under new domestic purchase contracts. Appendix B contains a similar listing of firms that sold uranium to US utilities during 1992 under new import purchase contracts. Appendix C contains an explanation of Form EIA-858 survey methodologies with emphasis on the processing of Schedule B data.

  18. Process for continuous production of metallic uranium and uranium alloys

    DOEpatents

    Hayden, H.W. Jr.; Horton, J.A.; Elliott, G.R.B.

    1995-06-06

    A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO{sub 3}), or any other substantially stable uranium oxide, to form the uranium dioxide (UO{sub 2}). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl{sub 4}), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation. 4 figs.

  19. Process for continuous production of metallic uranium and uranium alloys

    DOEpatents

    Hayden, Jr., Howard W.; Horton, James A.; Elliott, Guy R. B.

    1995-01-01

    A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO.sub.3), or any other substantially stable uranium oxide, to form the uranium dioxide (UO.sub.2). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl.sub.4), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation.

  20. Depleted uranium: A DOE management guide

    SciTech Connect

    1995-10-01

    The U.S. Department of Energy (DOE) has a management challenge and financial liability in the form of 50,000 cylinders containing 555,000 metric tons of depleted uranium hexafluoride (UF{sub 6}) that are stored at the gaseous diffusion plants. The annual storage and maintenance cost is approximately $10 million. This report summarizes several studies undertaken by the DOE Office of Technology Development (OTD) to evaluate options for long-term depleted uranium management. Based on studies conducted to date, the most likely use of the depleted uranium is for shielding of spent nuclear fuel (SNF) or vitrified high-level waste (HLW) containers. The alternative to finding a use for the depleted uranium is disposal as a radioactive waste. Estimated disposal costs, utilizing existing technologies, range between $3.8 and $11.3 billion, depending on factors such as applicability of the Resource Conservation and Recovery Act (RCRA) and the location of the disposal site. The cost of recycling the depleted uranium in a concrete based shielding in SNF/HLW containers, although substantial, is comparable to or less than the cost of disposal. Consequently, the case can be made that if DOE invests in developing depleted uranium shielded containers instead of disposal, a long-term solution to the UF{sub 6} problem is attained at comparable or lower cost than disposal as a waste. Two concepts for depleted uranium storage casks were considered in these studies. The first is based on standard fabrication concepts previously developed for depleted uranium metal. The second converts the UF{sub 6} to an oxide aggregate that is used in concrete to make dry storage casks.

  1. Preparation of uranium compounds

    DOEpatents

    Kiplinger, Jaqueline L; Montreal, Marisa J; Thomson, Robert K; Cantat, Thibault; Travia, Nicholas E

    2013-02-19

    UI.sub.3(1,4-dioxane).sub.1.5 and UI.sub.4(1,4-dioxane).sub.2, were synthesized in high yield by reacting turnings of elemental uranium with iodine dissolved in 1,4-dioxane under mild conditions. These molecular compounds of uranium are thermally stable and excellent precursor materials for synthesizing other molecular compounds of uranium including alkoxide, amide, organometallic, and halide compounds.

  2. Metals fact sheet - uranium

    SciTech Connect

    1996-04-01

    About 147 million pounds of this radioactive element are consumed annually by the worldwide nuclear power and weapons industries, as well as in the manufacture of ceramics and metal products. The heaviest naturally occurring element, uranium is typically found in intrusive granites, igneous and metamorphic veins, tabular sedimentary deposits, and unconformity-related structures. This article discusses the geology, exploitation, market, and applications of uranium and uranium ores.

  3. Nonmilitary applications of uranium

    SciTech Connect

    Polson, C.E.; Blasch, E.B.

    1981-01-01

    Uranium and its alloys should be considered for any application where weight and/or strength is required, or where weight to volume is important. There is considerable literature on uranium and its alloys. The fear of handling metallic uranium should not be a factor. It is the least hazardous of all long-lived isotopes. Sound industrial hygiene practices will provide adequate protection. In general, safety controls are similar to those required for other heavy metals.

  4. 10. VIEW OF DEPLETED URANIUM INGOT AND MOLD IN FOUNDRY. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW OF DEPLETED URANIUM INGOT AND MOLD IN FOUNDRY. (11/11/56) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  5. Biomonitoring of environmental pollution by thorium and uranium in selected regions of the Republic of Kazakhstan.

    PubMed

    Zoriy, P; Ostapczuk, P; Dederichs, H; Höbig, J; Lennartz, R; Zoriy, M

    2010-05-01

    Two former uranium mines and a uranium reprocessing factory in the city of Aktau, Kazakhstan, may represent a risk of contaminating the surrounding areas by uranium and its daughter elements. One of the possible fingerprinting tools for studying the environmental contamination is using plant samples, collected in the surroundings of this city in 2007 and 2008. The distribution pattern of environmental pollution by uranium and thorium was evaluated by determining the thorium and uranium concentrations in plant samples (Artemisia austriaca) from the city of Aktau and comparing these results with those obtained for the same species of plants from an unpolluted area (town of Kurchatov). The determination of the uranium and thorium concentrations in different parts of A. austriaca plants collected from the analyzed areas demonstrated that the main contamination of the flora in areas surrounding the city of Aktau was due to dust transported by the wind from the uranium mines. The results obtained demonstrate that all the areas surrounding Aktau have a higher pollution level due to thorium and uranium than the control area (Kurchatov). A few "hot points" with high concentrations of uranium and thorium were found near the uranium reprocessing factory and the uranium mines.

  6. Forensic analysis of uranium

    SciTech Connect

    Stoyer, N.J.; Moody, K.J.

    1996-10-01

    As more and more offers for illicit {open_quotes}Black Market{close_quotes} radioactive materials are found, the forensic information contained within the radioactive material itself becomes more important. Many {open_quotes}Black Market{close_quotes} offers are for uranium in various forms and enrichments. Although most are scams, some countries have actually interdicted enriched uranium. We will discuss the forensic information that can be obtained from materials containing uranium along with examples of data that has been determined from analysis of uranium samples obtained from legitimate sources.

  7. URANIUM RECOVERY PROCESS

    DOEpatents

    Kaufman, D.

    1958-04-15

    A process of recovering uranium from very low-grade ore residues is described. These low-grade uraniumcontaining hydroxide precipitates, which also contain hydrated silica and iron and aluminum hydroxides, are subjected to multiple leachings with aqueous solutions of sodium carbonate at a pH of at least 9. This leaching serves to selectively extract the uranium from the precipitate, but to leave the greater part of the silica, iron, and aluminum with the residue. The uranium is then separated from the leach liquor by the addition of an acid in sufficient amount to destroy the carbonate followed by the addition of ammonia to precipitate uranium as ammonium diuranate.

  8. PRODUCTION OF URANIUM

    DOEpatents

    Ruehle, A.E.; Stevenson, J.W.

    1957-11-12

    An improved process is described for the magnesium reduction of UF/sub 4/ to produce uranium metal. In the past, there have been undesirable premature reactions between the Mg and the bomb liner or the UF/sub 4/ before the actual ignition of the bomb reaction. Since these premature reactions impair the yield of uranium metal, they have been inhibited by forming a protective film upon the particles of Mg by reacting it with hydrated uranium tetrafluoride, sodium bifluoride, uranyl fluoride, or uranium trioxide. This may be accomplished by adding about 0.5 to 2% of the additive to the bomb charge.

  9. Uranium Dispersion & Dosimetry Model.

    SciTech Connect

    MICHAEL,; MOMENI, H.

    2002-03-22

    The Uranium Dispersion and Dosimetry (UDAD) program provides estimates of potential radiation exposure to individuals and to the general population in the vicinity of a uranium processing facility such as a uranium mine or mill. Only transport through the air is considered. Exposure results from inhalation, external irradiation from airborne and ground-deposited activity, and ingestion of foodstuffs. Individual dose commitments, population dose commitments, and environmental dose commitments are computed. The program was developed for application to uranium mining and milling; however, it may be applied to dispersion of any other pollutant.

  10. COATING URANIUM FROM CARBONYLS

    DOEpatents

    Gurinsky, D.H.; Storrs, S.S.

    1959-07-14

    Methods are described for making adherent corrosion resistant coatings on uranium metal. According to the invention, the uranium metal is heated in the presence of an organometallic compound such as the carbonyls of nickel, molybdenum, chromium, niobium, and tungsten at a temperature sufficient to decompose the metal carbonyl and dry plate the resultant free metal on the surface of the uranium metal body. The metal coated body is then further heated at a higher temperature to thermally diffuse the coating metal within the uranium bcdy.

  11. METHOD OF ROLLING URANIUM

    DOEpatents

    Smith, C.S.

    1959-08-01

    A method is described for rolling uranium metal at relatively low temperatures and under non-oxidizing conditions. The method involves the steps of heating the uranium to 200 deg C in an oil bath, withdrawing the uranium and permitting the oil to drain so that only a thin protective coating remains and rolling the oil coated uranium at a temperature of 200 deg C to give about a 15% reduction in thickness at each pass. The operation may be repeated to accomplish about a 90% reduction without edge cracking, checking or any appreciable increase in brittleness.

  12. URANIUM LEACHING AND RECOVERY PROCESS

    DOEpatents

    McClaine, L.A.

    1959-08-18

    A process is described for recovering uranium from carbonate leach solutions by precipitating uranium as a mixed oxidation state compound. Uranium is recovered by adding a quadrivalent uranium carbon;te solution to the carbonate solution, adjusting the pH to 13 or greater, and precipitating the uranium as a filterable mixed oxidation state compound. In the event vanadium occurs with the uranium, the vanadium is unaffected by the uranium precipitation step and remains in the carbonate solution. The uranium-free solution is electrolyzed in the cathode compartment of a mercury cathode diaphragm cell to reduce and precipitate the vanadium.

  13. Uranium industry annual 1993

    SciTech Connect

    Not Available

    1994-09-01

    Uranium production in the United States has declined dramatically from a peak of 43.7 million pounds U{sub 3}O{sub 8} (16.8 thousand metric tons uranium (U)) in 1980 to 3.1 million pounds U{sub 3}O{sub 8} (1.2 thousand metric tons U) in 1993. This decline is attributed to the world uranium market experiencing oversupply and intense competition. Large inventories of uranium accumulated when optimistic forecasts for growth in nuclear power generation were not realized. The other factor which is affecting U.S. uranium production is that some other countries, notably Australia and Canada, possess higher quality uranium reserves that can be mined at lower costs than those of the United States. Realizing its competitive advantage, Canada was the world`s largest producer in 1993 with an output of 23.9 million pounds U{sub 3}O{sub 8} (9.2 thousand metric tons U). The U.S. uranium industry, responding to over a decade of declining market prices, has downsized and adopted less costly and more efficient production methods. The main result has been a suspension of production from conventional mines and mills. Since mid-1992, only nonconventional production facilities, chiefly in situ leach (ISL) mining and byproduct recovery, have operated in the United States. In contrast, nonconventional sources provided only 13 percent of the uranium produced in 1980. ISL mining has developed into the most cost efficient and environmentally acceptable method for producing uranium in the United States. The process, also known as solution mining, differs from conventional mining in that solutions are used to recover uranium from the ground without excavating the ore and generating associated solid waste. This article describes the current ISL Yang technology and its regulatory approval process, and provides an analysis of the factors favoring ISL mining over conventional methods in a declining uranium market.

  14. Does uranium induce circulatory diseases? First results from a French cohort of uranium workers.

    PubMed

    Guseva Canu, Irina; Garsi, Jerome-Philippe; Caër-Lorho, Sylvaine; Jacob, Sophie; Collomb, Philippe; Acker, Alain; Laurier, Dominique

    2012-06-01

    Increased risk of circulatory system diseases (CSDs) was observed in nuclear workers handling uranium and plutonium in Russia and the UK. This work examines the CSD mortality after chronic intake of uranium among 2897 workers (79,892 person-years) at a uranium processing plant (1960-2006) in France. Cumulative exposure to different uranium compounds, classified by their isotopic composition and solubility type, was quantified on the basis of a plant-specific job-exposure matrix and individual job histories. HRs and associated 95% CI for CSD (n = 111) and specific CSD categories were estimated using Cox regression models, stratified on sex and birth cohort and adjusted for potential confounders. The effect of smoking was analysed among 260 smokers (42 CSD deaths). Compared to unexposed workers, CSD mortality was increased among workers exposed to slowly soluble reprocessed uranium (RPU) (HR = 2.13, 95% CI = 0.96 to 4.70) and natural uranium (HR = 1.73, 95% CI = 1.11 to 2.69). The risk increased with cumulative exposure and exposure duration. In the subgroup of smokers, the risk estimates were higher but with larger CIs: HR=1.91 (95% CI = 0.92 to 3.98) for natural uranium and HR = 4.78 (95% CI = 1.38 to 16.50) for RPU. The authors observed that exposure to slowly soluble uranium, namely RPU, may increase the risk of CSD mortality. However, these results are preliminary since the study is lacking statistical power and many other biological and lifestyle-related factors may cause CSD. More detailed investigations are necessary to confirm these findings and analyse in depth the effects of internal radiation exposure on the circulatory system.

  15. Uranium and cesium diffusion in fuel cladding of electrogenerating channel

    SciTech Connect

    Vasil’ev, I. V. Ivanov, A. S.; Churin, V. A.

    2014-12-15

    The results of reactor tests of a carbonitride fuel in a single-crystal cladding from a molybdenum-based alloy can be used in substantiating the operational reliability of fuels in developing a project of a megawatt space nuclear power plant. The results of experimental studies of uranium and cesium penetration into the single-crystal cladding of fuel elements with a carbonitride fuel are interpreted. Those fuel elements passed nuclear power tests in the Ya-82 pilot plant for 8300 h at a temperature of about 1500°C. It is shown that the diffusion coefficients for uranium diffusion into the cladding are virtually coincident with the diffusion coefficients measured earlier for uranium diffusion into polycrystalline molybdenum. It is found that the penetration of uranium into the cladding is likely to occur only in the case of a direct contact between the cladding and fuel. The experimentally observed nonmonotonic uranium-concentration profiles are explained in terms of predominant uranium diffusion along grain boundaries. It is shown that a substantially nonmonotonic behavior observed in our experiment for the uranium-concentration profile may be explained by the presence of a polycrystalline structure of the cladding in the surface region from its inner side. The diffusion coefficient is estimated for the grain-boundary diffusion of uranium. The diffusion coefficients for cesium are estimated on the basis of experimental data obtained in the present study.

  16. Bicarbonate Elution of Uranium from Amidoxime-Based Polymer Adsorbents for Sequestering Uranium from Seawater

    DOE PAGES

    Pan, Horng-Bin; Wai, Chien M.; Kuo, Li-Jung; ...

    2017-05-02

    Uranium adsorbed on amidoxime-based polyethylene fibers in simulated seawater can be quantitatively eluted using 3 M KHCO3 at 40°C. Thermodynamic calculations are in agreement with the experimental observation that at high bicarbonate concentrations (3 M) uranyl ions bound to amidoxime molecules are converted to uranyl tris-carbonato complex in the aqueous solution. The elution process is basically the reverse reaction of the uranium adsorption process which occurs at a very low bicarbonate concentration (~10-3 M) in seawater. The bicarbonate elution is followed by a NaOH treatment to remove natural organic matter adsorbed on the polymer adsorbent, in real seawater experiments. Furthermore,more » by using the sequential bicarbonate and NaOH elution, the adsorbent is reusable after rinsing with deionized water and the recycled adsorbent shows no loss of uranium loading capacity based on real seawater experiments.« less

  17. Uranium and Thorium

    ERIC Educational Resources Information Center

    Finch, Warren I.

    1978-01-01

    The results of President Carter's policy on non-proliferation of nuclear weapons are expected to slow the growth rate in energy consumption, put the development of the breeder reactor in question, halt plans to reprocess and recycle uranium and plutonium, and expand facilities to supply enriched uranium. (Author/MA)

  18. URANIUM SEPARATION PROCESS

    DOEpatents

    McVey, W.H.; Reas, W.H.

    1959-03-10

    The separation of uranium from an aqueous solution containing a water soluble uranyl salt is described. The process involves adding an alkali thiocyanate to the aqueous solution, contacting the resulting solution with methyl isobutyl ketons and separating the resulting aqueous and organic phase. The uranium is extracted in the organic phase as UO/sub 2/(SCN)/sub/.

  19. Uranium: A Dentist's perspective

    PubMed Central

    Toor, R. S. S.; Brar, G. S.

    2012-01-01

    Uranium is a naturally occurring radionuclide found in granite and other mineral deposits. In its natural state, it consists of three isotopes (U-234, U-235 and U-238). On an average, 1% – 2% of ingested uranium is absorbed in the gastrointestinal tract in adults. The absorbed uranium rapidly enters the bloodstream and forms a diffusible ionic uranyl hydrogen carbonate complex (UO2HCO3+) which is in equilibrium with a nondiffusible uranyl albumin complex. In the skeleton, the uranyl ion replaces calcium in the hydroxyapatite complex of the bone crystal. Although in North India, there is a risk of radiological toxicity from orally ingested natural uranium, the principal health effects are chemical toxicity. The skeleton and kidney are the primary sites of uranium accumulation. Acute high dose of uranyl nitrate delays tooth eruption, and mandibular growth and development, probably due to its effect on target cells. Based on all previous research and recommendations, the role of a dentist is to educate the masses about the adverse effects of uranium on the overall as well as the dental health. The authors recommended that apart from the discontinuation of the addition of uranium to porcelain, the Public community water supplies must also comply with the Environmental Protection Agency (EPA) standards of uranium levels being not more than 30 ppb (parts per billion). PMID:24478959

  20. International uranium market

    SciTech Connect

    Neff, T.L.; Jacoby, H.D.

    1980-12-01

    The international uranium market is affected by many of the same concerns that now attend all trade in energy: the adequacy of the resource base, price uncertainty, and worries about security of access. Uranium, like energy generally, is now a strategic commodity for reasons of economic security. Uranium is also the subject of international security concerns because of its association with the proliferation of nuclear weapons. Proliferation is a subject of disagreement among nations - with some arguing that access to uranium or enriched fuel should be coupled to restraint in technological decisions and acceptance of wide-ranging safeguards; the net result is yet another dimension of uncertainty about an energy commodity that many nations feel is vital to their future. These security concerns are related to the nature and behavior of the international market for nuclear fuels. Without adequate information, the worst is usually assumed. Thus, a clearer view of the nature of supply and demand, of government policy formulation, and of market functioning can help relieve at least some of the security worries felt by those in charge of national energy policies. It is the purpose of this paper to improve this understanding. The following topics are discussed: Uranium Demand; Uranium Supply; Major Uranium Producers - Australia, Canada, South Africa, Namibia, Niger; Major Consumers - Japan, France, West Germany; The Uranium Market; and Issues and Implications.

  1. Uranium and Thorium

    ERIC Educational Resources Information Center

    Finch, Warren I.

    1978-01-01

    The results of President Carter's policy on non-proliferation of nuclear weapons are expected to slow the growth rate in energy consumption, put the development of the breeder reactor in question, halt plans to reprocess and recycle uranium and plutonium, and expand facilities to supply enriched uranium. (Author/MA)

  2. DECONTAMINATION OF URANIUM

    DOEpatents

    Spedding, F.H.; Butler, T.A.

    1962-05-15

    A process is given for separating fission products from uranium by extracting the former into molten aluminum. Phase isolation can be accomplished by selectively hydriding the uranium at between 200 and 300 deg C and separating the hydride powder from coarse particles of fissionproduct-containing aluminum. (AEC)

  3. Impact of a Real Microgravity on the Productivity of Tomato Plants and Resistance to Viruses

    NASA Astrophysics Data System (ADS)

    Mishchenko, L. T.; Dunich, A. A.; Danilova, O. I.

    2013-02-01

    It was detected that space flight factors increased tomato productivity that is important for using such plants as cosmonauts nutrition in long-term space missions. It was revealed that tomato plants, whose seeds were exposed to long space flight conditions, are more resistant to viruses and have higher polyphenols concentration than in the stationary control.

  4. METHOD FOR PURIFYING URANIUM

    DOEpatents

    Kennedy, J.W.; Segre, E.G.

    1958-08-26

    A method is presented for obtaining a compound of uranium in an extremely pure state and in such a condition that it can be used in determinations of the isotopic composition of uranium. Uranium deposited in calutron receivers is removed therefrom by washing with cold nitric acid and the resulting solution, coataining uranium and trace amounts of various impurities, such as Fe, Ag, Zn, Pb, and Ni, is then subjected to various analytical manipulations to obtain an impurity-free uranium containing solution. This solution is then evaporated on a platinum disk and the residue is ignited converting it to U2/sub 3//sub 8/. The platinum disk having such a thin film of pure U/sub 2/O/sub 8/ is suitable for use with isotopic determination techaiques.

  5. Uranium dioxide electrolysis

    DOEpatents

    Willit, James L [Batavia, IL; Ackerman, John P [Prescott, AZ; Williamson, Mark A [Naperville, IL

    2009-12-29

    This is a single stage process for treating spent nuclear fuel from light water reactors. The spent nuclear fuel, uranium oxide, UO.sub.2, is added to a solution of UCl.sub.4 dissolved in molten LiCl. A carbon anode and a metallic cathode is positioned in the molten salt bath. A power source is connected to the electrodes and a voltage greater than or equal to 1.3 volts is applied to the bath. At the anode, the carbon is oxidized to form carbon dioxide and uranium chloride. At the cathode, uranium is electroplated. The uranium chloride at the cathode reacts with more uranium oxide to continue the reaction. The process may also be used with other transuranic oxides and rare earth metal oxides.

  6. Uranium triamidoamine chemistry.

    PubMed

    Gardner, Benedict M; Liddle, Stephen T

    2015-07-07

    Triamidoamine (Tren) complexes of the p- and d-block elements have been well-studied, and they display a diverse array of chemistry of academic, industrial and biological significance. Such in-depth investigations are not as widespread for Tren complexes of uranium, despite the general drive to better understand the chemical behaviour of uranium by virtue of its fundamental position within the nuclear sector. However, the chemistry of Tren-uranium complexes is characterised by the ability to stabilise otherwise reactive, multiply bonded main group donor atom ligands, construct uranium-metal bonds, promote small molecule activation, and support single molecule magnetism, all of which exploit the steric, electronic, thermodynamic and kinetic features of the Tren ligand system. This Feature Article presents a current account of the chemistry of Tren-uranium complexes.

  7. URANIUM PRECIPITATION PROCESS

    DOEpatents

    Thunaes, A.; Brown, E.A.; Smith, H.W.; Simard, R.

    1957-12-01

    A method for the recovery of uranium from sulfuric acid solutions is described. In the present process, sulfuric acid is added to the uranium bearing solution to bring the pH to between 1 and 1.8, preferably to about 1.4, and aluminum metal is then used as a reducing agent to convert hexavalent uranium to the tetravalent state. As the reaction proceeds, the pH rises amd a selective precipitation of uranium occurs resulting in a high grade precipitate. This process is an improvement over the process using metallic iron, in that metallic aluminum reacts less readily than metallic iron with sulfuric acid, thus avoiding consumption of the reducing agent and a raising of the pH without accomplishing the desired reduction of the hexavalent uranium in the solution. Another disadvantage to the use of iron is that positive ferric ions will precipitate with negative phosphate and arsenate ions at the pH range employed.

  8. Mixtures in the real world: The importance of plant self-defense toxicants, mycotoxins, and the human diet

    SciTech Connect

    Mattsson, Joel L.

    2007-09-01

    A perusal of research presented at the Annual Society of Toxicology Meetings, or in nearly any toxicology journal, will show that the overwhelming emphasis of toxicology research is on synthetic chemistries. Because of substantial potency and exposure to natural chemicals, the overwhelming focus on synthetic chemistries cannot lead to a realistic understanding of chemical risk to the general population. Natural chemicals, simply because of their abundance and potency, may be as likely to be a public health concern and to be involved in chemical interactions (natural:natural, natural:pharmaceutical; or natural:synthetic) as are environmental levels of synthetic chemicals. All plants have a mix of natural self-defense chemistries and mycotoxins that, when tested in a manner comparable to synthetic pesticides, cause the entire spectrum of toxic effects. As a further complication, plants also escalate much of their self-defense chemistry when attacked by insects and fungi, and damaged crops often have higher mycotoxins levels. Effective crop protection will typically reduce the plant's levels of self-defense toxicants and mycotoxins, but may add residues of synthetic pesticides or add some other risk variable. In addition, cooking may also alter the food chemistry (e.g., acrylamide). The mixtures toxicologist needs to address the real world mixture of natural and synthetic chemicals. Public policy on crop-food safety cannot be sensibly guided without these data and large voids in our understanding of risks from real-world mixtures cannot be in the public interest.

  9. Uranium recovery from wet process phosphoric acid

    SciTech Connect

    Carrington, O.F.; Pyrih, R.Z.; Rickard, R.S.

    1981-03-24

    Improvement in the process for recovering uranium from wetprocess phosphoric acid solution derived from the acidulation of uraniferous phosphate ores by the use of two ion exchange liquidliquid solvent extraction circuits in which in the first circuit (A) the uranium is reduced to the uranous form; (B) the uranous uranium is recovered by liquid-liquid solvent extraction using a mixture of mono- and di-(Alkyl-phenyl) esters of orthophosphoric acid as the ion exchange agent; and (C) the uranium oxidatively stripped from the agent with phosphoric acid containing an oxidizing agent to convert uranous to uranyl ions, and in the second circuit (D) recovering the uranyl uranium from the strip solution by liquid-liquid solvent extraction using di(2ethylhexyl)phosphoric acid in the presence of trioctylphosphine oxide as a synergist; (E) scrubbing the uranium loaded agent with water; (F) stripping the loaded agent with ammonium carbonate, and (G) calcining the formed ammonium uranyl carbonate to uranium oxide, the improvement comprising: (1) removing the organics from the raffinate of step (B) before recycling the raffinate to the wet-process plant, and returning the recovered organics to the circuit to substantially maintain the required balance between the mono and disubstituted esters; (2) using hydogren peroxide as the oxidizing agent in step (C); (3) using an alkali metal carbonate as the stripping agent in step (F) following by acidification of the strip solution with sulfuric acid; (4) using some of the acidified strip solution as the scrubbing agent in step (E) to remove phosphorus and other impurities; and (5) regenerating the alkali metal loaded agent from step (F) before recycling it to the second circuit.

  10. Toxic influence of silver and uranium salts on activated sludge of wastewater treatment plants and synthetic activated sludge associates modeled on its pure cultures.

    PubMed

    Tyupa, Dmitry V; Kalenov, Sergei V; Skladnev, Dmitry A; Khokhlachev, Nikolay S; Baurina, Marina M; Kuznetsov, Alexander Ye

    2015-01-01

    Toxic impact of silver and uranium salts on activated sludge of wastewater treatment facilities has been studied. Some dominating cultures (an active nitrogen fixer Agrobacterium tumifaciens (A.t) and micromyces such as Fusarium nivale, Fusarium oxysporum, and Penicillium glabrum) have been isolated and identified as a result of selection of the activated sludge microorganisms being steadiest under stressful conditions. For these cultures, the lethal doses of silver amounted 1, 600, 50, and 300 µg/l and the lethal doses of uranium were 120, 1,500, 1,000, and 1,000 mg/l, respectively. A.tumifaciens is shown to be more sensitive to heavy metals than micromyces. Synthetic granular activated sludge was formed on the basis of three cultures of the isolated micromyces steadiest against stress. Its granules were much more resistant to silver than the whole native activated sludge was. The concentration of silver causing 50 % inhibition of synthetic granular activated sludge growth reached 160-170 μg/l as far as for the native activated sludge it came only to 100-110 μg/l.

  11. Issues and recommendations related to replacement of CFC-114 at the uranium enrichment gaseous diffusion plant. Task title: Chlorofluorocarbon (CFC) Program Review, Final report, August 1, 1991--October 1, 1992

    SciTech Connect

    Anderson, B.L.; Banaghan, E.

    1993-03-31

    The operating uranium enrichment gaseous diffusion plants (GDPs) in Portsmouth, Ohio and Paducah, Kentucky, which are operated for the United States Department for Energy by Martin Marietta Energy Systems (MMES), currently use a chlorofluorocarbon (CFC-114) as the primary process stream coolant. Due to recent legislation embodied in the Clean Air Act, the production of this and other related chlorofluorocarbons (CFCS) are to be phased out with no production occurring after 1995. Since the plants lose approximately 500,000 pounds per year of this process stream coolant through various leaks, the GDPs are faced with the challenge of identifying a replacement coolant that will allow continued operation of the plants. MMES formed the CFC Task Team to identify and solve the various problems associated with identifying and implementing a replacement coolant. This report includes a review of the work performed by the CFC Task Team, and recommendations that were formulated based on this review and upon original work. The topics covered include; identifying a replacement coolant, coolant leak detection and repair efforts, coolant safety concerns, coolant level sensors, regulatory issues, and an analytical decision analysis.

  12. Demonstration of jackhammer incorporating depleted uranium

    SciTech Connect

    Fischer, L E; Hoard, R W; Carter, D L; Saculla, M D; Wilson, G V

    2000-04-01

    The United States Government currently has an abundance of depleted uranium (DU). This surplus of about 1 billion pounds is the result of an enrichment process using gaseous diffusion to produce enriched and depleted uranium. The enriched uranium has been used primarily for either nuclear weapons for the military or nuclear fuel for the commercial power industry. Most of the depleted uranium remains at the enrichment process plants in the form of depleted uranium hexafluoride (DUF{sub 6}). The Department of Energy (DOE) recently began a study to identify possible commercial applications for the surplus material. One of these potential applications is to use the DU in high-density strikers/hammers in pneumatically driven tools, such as jack hammers and piledrivers to improve their impulse performance. The use of DU could potentially increase tunneling velocity and excavation into target materials with improved efficiency. This report describes the efforts undertaken to analyze the particulars of using DU in two specific striking applications: the jackhammer and chipper tool.

  13. PROCESS OF RECOVERING URANIUM

    DOEpatents

    Kilner, S.B.

    1959-12-29

    A method is presented for separating and recovering uranium from a complex mixure of impurities. The uranium is dissolved to produce an aqueous acidic solution including various impurities. In accordance with one method, with the uranium in the uranyl state, hydrogen cyanide is introduced into the solution to complex the impurities. Subsequently, ammonia is added to the solution to precipitate the uraniunn as ammonium diuranate away from the impurities in the solution. Alternatively, the uranium is precipitated by adding an alkaline metal hydroxide. In accordance with the second method, the uranium is reduced to the uranous state in the solution. The reduced solution is then treated with solid alkali metal cyanide sufficient to render the solution about 0.1 to 1.0 N in cyanide ions whereat cyanide complex ions of the metal impurities are produced and the uranium is simultaneously precipituted as uranous hydroxide. Alternatively, hydrogen cyanide may be added to the reduced solution and the uranium precipitated subsequently by adding ammonium hydroxide or an alkali metal hydroxide. Other refinements of the method are also disclosed.

  14. Application of phytoextraction for uranium contaminated soil in korea

    NASA Astrophysics Data System (ADS)

    Ryu, Y.; Han, Y.; Lee, M.

    2013-12-01

    The soils having high concentration of uranium, sampled from Goesan Deokpyungri area in Korea, were identified with the uranium removal efficiency of phytoextraction by using several plants. According to the results of physicochemical properties, uranium concentration from soil was 28.85mg/kg, pH 5.43 and soil texture was "Sand". Results of SEP(Sequential Extraction Procedure) test, uranium concentrations ratio of soil in the status of exchangeable/carbonate was 13.4%. Five plants such as Lettuce (Lactuca sativa L.), Chinese cabbage (Brassica campestris L.), Sweet potato (Ipomoea batatas (L.) Lam), Radish (Raphanus sativus), Sesame (Perilla frutescens var. japonica) were cultivated during 56 days in phytotron. All the cultivation processes were conducted in a growth chamber at 25 degrees celsius, 70% relative humidity, 4000 Lux illumination (16 hours/day) and CO2 concentration of 600 ppm. Four times at intervals of 2 weeks leaves and roots collected were analyzed for uranium concentration. Ranges of uranium concentration of the roots and leaves from the five plants were measured to 206.81-721.22μg/kg and 3.45-10.21μg/kg respectively. The majority of uranium was found to accumulate in the roots. Uranium concentration in the leaves, regardless of the type of plants were presented below standard of drinking water(30μg/l) by U.S EPA. Phytoextraction pot experiments with citric acid were conducted. Citric acid as chelating agent was applied to soil to enhance uranium accumulation in five crop plants. 6 days before harvest crops, Each citric acid 25mM and 50mM was injected into the soil by 300ml. After injecting citric acid 25mM , pH of the soil was reduced to 4.95. Uranium concentration of leaves and roots collected from five plants was increased to 2-4times and 7-30times compared to control soil. Injected with citric acid 50mM , pH of the soil was reduced to 4.79. Uranium concentration of leaves and roots collected from five plants was increased to 3-10times and 10

  15. Depleted uranium management alternatives

    SciTech Connect

    Hertzler, T.J.; Nishimoto, D.D.

    1994-08-01

    This report evaluates two management alternatives for Department of Energy depleted uranium: continued storage as uranium hexafluoride, and conversion to uranium metal and fabrication to shielding for spent nuclear fuel containers. The results will be used to compare the costs with other alternatives, such as disposal. Cost estimates for the continued storage alternative are based on a life-cycle of 27 years through the year 2020. Cost estimates for the recycle alternative are based on existing conversion process costs and Capital costs for fabricating the containers. Additionally, the recycle alternative accounts for costs associated with intermediate product resale and secondary waste disposal for materials generated during the conversion process.

  16. Recovery of uranium values

    DOEpatents

    Brown, K. B.; Crouse, Jr., D. J.; Moore, J. G.

    1959-03-10

    A liquid-liquid extraction method is presented for recovering uranium values from an aqueous acidic solution by means of certain high molecular weight amine fn the amine classes of primary, secondary, heterocyclic secondary, tertiary, or heterocyclic tertiary. The uranium bearing aqueous acidic solution is contacted with the selected anine dissolved in a nonpolar waterimmiscible organfc solvent such as kerosene. The uranium which is substantially completely extracted by the organic phase may be stripped therefrom by water, and recovered from the aqueous phase by treatment into ammonia to precipitate ammonium diuranate.

  17. RECOVERY OF URANIUM VALUES

    DOEpatents

    Brown, K.B.; Crouse, D.J. Jr.; Moore, J.G.

    1959-03-10

    A liquid-liquid extraction method is presented for recovering uranium values from an aqueous acidic solution by means of certain high molecular weight amine in the amine classes of primary, secondary, heterocyclic secondary, tertiary, or heterocyclic tertiary. The uranium bearing aqueous acidic solution is contacted with the selected amine dissolved in a nonpolar water-immiscible organic solvent such as kerosene. The uranium which is substantially completely exiracted by the organic phase may be stripped therefrom by waters and recovered from the aqueous phase by treatment into ammonia to precipitate ammonium diuranate.

  18. Multiplex real-time PCR for detection, identification and quantification of 'Candidatus Liberibacter solanacearum' in potato plants with zebra chip.

    PubMed

    Li, Wenbin; Abad, Jorge A; French-Monar, Ronald D; Rascoe, John; Wen, Aimin; Gudmestad, Neil C; Secor, Gary A; Lee, Ing-Ming; Duan, Yongping; Levy, Laurene

    2009-07-01

    The new Liberibacter species, 'Candidatus Liberibacter solanacearum' (Lso) recently associated with potato/tomato psyllid-transmitted diseases in tomato and capsicum in New Zealand, was found to be consistently associated with a newly emerging potato zebra chip (ZC) disease in Texas and other southwestern states in the USA. A species-specific primer LsoF was developed for both quantitative real-time PCR (qPCR) and conventional PCR (cPCR) to detect and quantify Lso in infected samples. In multiplex qPCR, a plant cytochrome oxidase (COX)-based probe-primer set was used as a positive internal control for host plants, which could be used to reliably access the DNA extraction quality and to normalize qPCR data for accurate quantification of the bacterial populations in environment samples. Neither the qPCR nor the cPCR using the primer and/or probe sets with LsoF reacted with other Liberibacter species infecting citrus or other potato pathogens. The low detection limit of the multiplex qPCR was about 20 copies of the target 16S rDNA templates per reaction for field samples. Lso was readily detected and quantified in various tissues of ZC-affected potato plants collected from fields in Texas. A thorough but uneven colonization of Lso was revealed in various tissues of potato plants. The highest Lso populations were about 3x10(8) genomes/g tissue in the root, which were 3-order higher than those in the above-ground tissues of potato plants. The Lso bacterial populations were normally distributed across the ZC-affected potato plants collected from fields in Texas, with 60% of ZC-affected potato plants harboring an average Lso population from 10(5) to 10(6) genomes/g tissue, 4% of plants hosting above 10(7) Lso genomes/g tissue, and 8% of plants holding below 10(3) Lso genomes/g tissue. The rapid, sensitive, specific and reliable multiplex qPCR showed its potential to become a powerful tool for early detection and quantification of the new Liberibacter species associated

  19. A generic task approach to a real time nuclear power plant fault diagnosis and advisory system

    SciTech Connect

    Hajek, B.K.; Miller, D.W.; Bhatnagar, R.; Stasenko, J.E.; Punch, W.F. III; Yamada, N.

    1988-01-01

    A generic task toolkit developed at The Ohio State University Laboratory for Artificial Intelligence Research (LAIR) has been used in the development of an aid for operators of nuclear power plants. The toolkit consists of high level programming tools that enable knowledge to be used in accordance with its need. That is, if diagnosis is the need, a framework for performing diagnosis is provided. The operator aid provides for monitoring the conditions in the plant, detecting abnormal events, and providing the operator with guidance and advice through procedures on what path should be followed to mitigate the consequences. 8 refs., 5 figs.

  20. Real Time Demonstration Project XRF Performance Evaluation Report for Paducah Gaseous Diffusion Plant AOC 492

    SciTech Connect

    Johnson, Robert L

    2008-04-03

    This activity was undertaken to demonstrate the applicability of market-available XRF instruments to quantify metal concentrations relative to background and risk-based action and no action levels in Paducah Gaseous Diffusion Plant (PGDP) soils. As such, the analysis below demonstrates the capabilities of the instruments relative to soil characterization applications at the PGDP.

  1. On developing and enhancing plant-level disease rating systems in real fields

    USDA-ARS?s Scientific Manuscript database

    Cercospora leaf spot (CLS) is one of the most serious diseases in sugar beet plants causing an enormous decrease in the sugar production throughout the world. Agricultural researchers are continuously seeking CLS-resistant sugar beet cultivars. Normally human experts manually observe and rate the re...

  2. Depleted Uranium: Technical Brief

    EPA Pesticide Factsheets

    This technical brief provides accepted data and references to additional sources for radiological and chemical characteristics, health risks and references for both the monitoring and measurement, and applicable treatment techniques for depleted uranium.

  3. Uranium Location Database Compilation

    EPA Pesticide Factsheets

    EPA has compiled mine location information from federal, state, and Tribal agencies into a single database as part of its investigation into the potential environmental hazards of wastes from abandoned uranium mines in the western United States.

  4. PURIFICATION OF URANIUM FUELS

    DOEpatents

    Niedrach, L.W.; Glamm, A.C.

    1959-09-01

    An electrolytic process of refining or decontaminating uranium is presented. The impure uranium is made the anode of an electrolytic cell. The molten salt electrolyte of this cell comprises a uranium halide such as UF/sub 4/ or UCl/sub 3/ and an alkaline earth metal halide such as CaCl/sub 2/, BaF/sub 2/, or BaCl/sub 2/. The cathode of the cell is a metal such as Mn, Cr, Co, Fe, or Ni which forms a low melting eutectic with U. The cell is operated at a temperature below the melting point of U. In operation the electrodeposited uranium becomes alloyed with the metal of the cathode, and the low melting alloy thus formed drips from the cathode.

  5. URANIUM RECOVERY PROCESS

    DOEpatents

    Stevenson, J.W.; Werkema, R.G.

    1959-07-28

    The recovery of uranium from magnesium fluoride slag obtained as a by- product in the production of uranium metal by the bomb reduction prccess is presented. Generally the recovery is accomplished by finely grinding the slag, roasting ihe ground slag air, and leaching the roasted slag with a hot, aqueous solution containing an excess of the sodium bicarbonate stoichiometrically required to form soluble uranium carbonate complex. The roasting is preferably carried out at between 425 and 485 deg C for about three hours. The leaching is preferably done at 70 to 90 deg C and under pressure. After leaching and filtration the uranium may be recovered from the clear leach liquor by any desired method.

  6. 300 AREA URANIUM CONTAMINATION

    SciTech Connect

    BORGHESE JV

    2009-07-02

    {sm_bullet} Uranium fuel production {sm_bullet} Test reactor and separations experiments {sm_bullet} Animal and radiobiology experiments conducted at the. 331 Laboratory Complex {sm_bullet} .Deactivation, decontamination, decommissioning,. and demolition of 300 Area facilities

  7. Uranium purchases report 1993

    SciTech Connect

    Not Available

    1994-08-10

    Data reported by domestic nuclear utility companies in their responses to the 1991 through 1993 ``Uranium Industry Annual Survey,`` Form EIA-858, Schedule B,`` Uranium Marketing Activities,`` are provided in response to the requirements in the Energy Policy Act 1992. Appendix A contains an explanation of Form EIA-858 survey methodologies with emphasis on the processing of Schedule B data. Additional information published in this report not included in Uranium Purchases Report 1992, includes a new data table. Presented in Table 1 are US utility purchases of uranium and enrichment services by origin country. Also, this report contains additional purchase information covering average price and contract duration. Table 2 is an update of Table 1 and Table 3 is an update of Table 2 from the previous year`s report. The report contains a glossary of terms.

  8. Uranium concentrations in asparagus

    SciTech Connect

    Tiller, B.L.; Poston, T.M.

    1992-05-01

    Concentrations of uranium were determined in asparagus collected from eight locations near and ten locations on the Hanford Site southcentral Washington State. Only one location (Sagemoor) had samples with elevated concentrations. The presence of elevated uranium in asparagus at Sagemoor may be explained by the elevated levels in irrigation water. These levels of uranium are comparable to levels previously reported upstream and downstream of the 300-FF-1 Operable Unit on the Hanford Site (0.0008 {mu}g/g), but were below the 0.020-{mu}g/g level reported for brush collected at Sagemoor in a 1982 study. Concentrations at all other onsite and offsite sample locations were considerably lower than concentrations reported immediately upstream and downstream of the 300-FF-1 Operable Unit. Using an earlier analysis of the uranium concentrations in asparagus collected from the Hanford Site constitutes a very small fraction of the US Department of Energy effective dose equivalent limit of 100 mrem.

  9. Method for the recovery of uranium values from uranium tetrafluoride

    DOEpatents

    Kreuzmann, Alvin B.

    1983-01-01

    The invention is a novel method for the recovery of uranium from dry, particulate uranium tetrafluoride. In one aspect, the invention comprises reacting particulate uranium tetrafluoride and calcium oxide in the presence of gaseous oxygen to effect formation of the corresponding alkaline earth metal uranate and alkaline earth metal fluoride. The product uranate is highly soluble in various acidic solutions wherein the product fluoride is virtually insoluble therein. The product mixture of uranate and alkaline earth metal fluoride is contacted with a suitable acid to provide a uranium-containing solution, from which the uranium is recovered. The invention can achieve quantitative recovery of uranium in highly pure form.

  10. Method for the recovery of uranium values from uranium tetrafluoride

    DOEpatents

    Kreuzmann, A.B.

    1982-10-27

    The invention is a novel method for the recovery of uranium from dry, particulate uranium tetrafluoride. In one aspect, the invention comprises reacting particulate uranium tetrafluoride and calcium oxide in the presence of gaseous oxygen to effect formation of the corresponding alkaline earth metal uranate and alkaline earth metal fluoride. The product uranate is highly soluble in various acidic solutions whereas the product fluoride is virtually insoluble therein. The product mixture of uranate and alkaline earth metal fluoride is contacted with a suitable acid to provide a uranium-containing solution, from which the uranium is recovered. The invention can achieve quantitative recovery of uranium in highly pure form.

  11. ANODIC TREATMENT OF URANIUM

    DOEpatents

    Kolodney, M.

    1959-02-01

    A method is presented for effecting eloctrolytic dissolution of a metallic uranium article at a uniform rate. The uranium is made the anode in an aqueous phosphoric acid solution containing nitrate ions furnished by either ammonium nitrate, lithium nitrate, sodium nitrate, or potassium nitrate. A stainless steel cathode is employed and electrolysls carried out at a current density of about 0.1 to 1 ampere per square inch.

  12. URANIUM SEPARATION PROCESS

    DOEpatents

    Lyon, W.L.

    1962-04-17

    A method of separating uranium oxides from PuO/sub 2/, ThO/sub 2/, and other actinide oxides is described. The oxide mixture is suspended in a fused salt melt and a chlorinating agent such as chlorine gas or phosgene is sparged through the suspension. Uranium oxides are selectively chlorinated and dissolve in the melt, which may then be filtered to remove the unchlorinated oxides of the other actinides. (AEC)

  13. Uranium purchases report 1994

    SciTech Connect

    1995-07-01

    US utilities are required to report to the Secretary of Energy annually the country of origin and the seller of any uranium or enriched uranium purchased or imported into the US, as well as the country of origin and seller of any enrichment services purchased by the utility. This report compiles these data and also contains a glossary of terms and additional purchase information covering average price and contract duration. 3 tabs.

  14. Worldwide developments in uranium

    SciTech Connect

    Hoellen, E.E.

    1987-05-01

    World uranium production will continue to change in most major producing nations. Canadian production will increase and will be increasingly dominated by western producers as eastern Canadian high-cost production declines. Australian production will increase as major projects come into operation before 2000. US production will stabilize through the end of the century. South African production will be dependent upon the worldwide support for economic sanctions. China's entry into the world market injects yet another variable into the already cloudy supply picture. Many risks and uncertainties will face uranium producers through the 1980s. Recognizing that the uranium industry is not a fast-growing market, many existing and potential producers are seeking alternate investment courses, causing a restructuring of the world uranium production industry in ways not anticipated even a few years ago. During the restructuring process, world uranium production will most likely continue to exceed uranium consumption, resulting in a further buildup of world uranium inventories. Inventory sales will continue to redistribute this material. As inventory selling runs its course, users will turn to normal sources of supply, stimulating additional production to meet needs. Stimulation in the form of higher prices will be determined by how fast producers are willing and able to return to the market. Production costs are expected to have an increasing impact as it has become apparent that uranium resources are large in comparison to projected consumption. Conversely, security-of-supply issues have seemed to be of decreasing magnitude as Canada, Australia, and other non-US producers continue to meet delivery commitments.

  15. URANIUM EXTRACTION PROCESS

    DOEpatents

    Baldwin, W.H.; Higgins, C.E.

    1958-12-16

    A process is described for recovering uranium values from acidic aqueous solutions containing hexavalent uranium by contacting the solution with an organic solution comprised of a substantially water-immiscible organlc diluent and an organic phosphate to extract the uranlum values into the organic phase. Carbon tetrachloride and a petroleum hydrocarbon fraction, such as kerosene, are sultable diluents to be used in combination with organlc phosphates such as dibutyl butylphosphonate, trlbutyl phosphine oxide, and tributyl phosphate.

  16. Toxicity of Depleted Uranium

    DTIC Science & Technology

    1997-02-01

    Exposure to Uranium Hexafluoride NUREG /CR- 5566, PNL-7328, Prepared for US Nuclear Regulatory Commission, Washington, DC, 1990. 27. Thun MJ, Baker DB... NUREG /CR-495 1, Prepared for US Nuclear Regulatory Commission, Washington, DC, 1987. 31. Morrow PE, Leach LJ, Smith FA, Goloin RM, Scott JB, Belter HD...of Uranium Hexafluoride, NUREG /CR- 2268, RH, Prepared for Division of Health Siting and Waste Management, Washington, DC, 1982. 32. Eidson AF, Damon

  17. Soviet uranium supply capability

    SciTech Connect

    1990-02-01

    For many years, only limited information concerning uranium deposits in the USSR has been available from Soviet sources. The Soviet Union has, however, cooperated in some past efforts to promote interaction with the international scientific community. For example, in 1984 the Soviet Union hosted the 27th International Geological Congress (IGC). The uranium portion included 50 papers, primarily on uranium deposits in sandstone and metamorphic rocks, presented to about 300 members. The IGC sponsored almost 400 geology field trips, the most noteworthy of which was a five-day trip to the Krivoi Rog iron and uranium district in the south-central Ukraine, including visits to two open-pit iron mines and the underground Novaya uranium mine in Zholtye Vody. That conference was reported in detail on the October 1984 NUEXCO Monthly Report. Some other information that has been made available over the years is contained in the April 1985 Report discussion of uranium deposit classifications. Advanced processing technology, low-cost labor, by-product and co-product recovery, and the large existing production capacity enable MAEI to produce nuclear fuel at low cost. The Soviet Union`s reserve base, technological development, and production experience make it one of the world`s leading producers of nuclear fuel. As additional information is made available for publication, NUEXCO will present updated reports on the nuclear fuel cycle facilities in the Soviet Union.

  18. Selective Extraction of Uranium from Liquid or Supercritical Carbon Dioxide

    SciTech Connect

    Farawila, Anne F.; O'Hara, Matthew J.; Wai, Chien M.; Taylor, Harry Z.; Liao, Yu-Jung

    2012-07-31

    Current liquid-liquid extraction processes used in recycling irradiated nuclear fuel rely on (1) strong nitric acid to dissolve uranium oxide fuel, and (2) the use of aliphatic hydrocarbons as a diluent in formulating the solvent used to extract uranium. The nitric acid dissolution process is not selective. It dissolves virtually the entire fuel meat which complicates the uranium extraction process. In addition, a solvent washing process is used to remove TBP degradation products, which adds complexity to the recycling plant and increases the overall plant footprint and cost. A liquid or supercritical carbon dioxide (l/sc -CO2) system was designed to mitigate these problems. Indeed, TBP nitric acid complexes are highly soluble in l/sc -CO2 and are capable of extracting uranium directly from UO2, UO3 and U3O8 powders. This eliminates the need for total acid dissolution of the irradiated fuel. Furthermore, since CO2 is easily recycled by evaporation at room temperature and pressure, it eliminates the complex solvent washing process. In this report, we demonstrate: (1) A reprocessing scheme starting with the selective extraction of uranium from solid uranium oxides into a TBP-HNO3 loaded Sc-CO2 phase, (2) Back extraction of uranium into an aqueous phase, and (3) Conversion of recovered purified uranium into uranium oxide. The purified uranium product from step 3 can be disposed of as low level waste, or mixed with enriched uranium for use in a reactor for another fuel cycle. After an introduction on the concept and properties of supercritical fluids, we first report the characterization of the different oxides used for this project. Our extraction system and our online monitoring capability using UV-Vis absorbance spectroscopy directly in sc-CO2 is then presented. Next, the uranium extraction efficiencies and kinetics is demonstrated for different oxides and under different physical and chemical conditions: l/sc -CO2 pressure and temperature, TBP/HNO3 complex used

  19. Online, real-time detection of volatile emissions from plant tissue

    PubMed Central

    Harren, Frans J. M.; Cristescu, Simona M.

    2013-01-01

    Trace gas monitoring plays an important role in many areas of life sciences ranging from agrotechnology, microbiology, molecular biology, physiology, and phytopathology. In plants, many processes can be followed by their low-concentration gas emission, for compounds such as ethylene, nitric oxide, ethanol or other volatile organic compounds (VOCs). For this, numerous gas-sensing devices are currently available based on various methods. Among them are the online trace gas detection methods; these have attracted much interest in recent years. Laser-based infrared spectroscopy and proton transfer reaction mass spectrometry are the two most widely used methods, thanks to their high sensitivity at the single part per billion level and their response time of seconds. This paper starts with a short description of each method and presents performances within a wide variety of biological applications. Using these methods, the dynamics of trace gases for ethylene, nitric oxide and other VOCs released by plants under different conditions are recorded and analysed under natural conditions. In this way many hypotheses can be tested, revealing the role of the key elements in signalling and action mechanisms in plants. PMID:23429357

  20. Real Time Live Imaging of Phytopathogenic Bacteria Xanthomonas campestris pv. campestris MAFF106712 in ‘Plant Sweet Home’

    PubMed Central

    Akimoto-Tomiyama, Chiharu; Furutani, Ayako; Ochiai, Hirokazu

    2014-01-01

    Xanthomonas is one of the most widespread phytobacteria, causing diseases on a variety of agricultural plants. To develop novel control techniques, knowledge of bacterial behavior inside plant cells is essential. Xanthomonas campestris pv. campestris, a vascular pathogen, is the causal agent of black rot on leaves of Brassicaceae, including Arabidopsis thaliana. Among the X. campestris pv. campestris stocks in the MAFF collection, we selected XccMAFF106712 as a model compatible pathogen for the A. thaliana reference ecotype Columbia (Col-0). Using modified green fluorescent protein (AcGFP) as a reporter, we observed real time XccMAFF106712 colonization in planta with confocal microscopy. AcGFP-expressing bacteria colonized the inside of epidermal cells and the apoplast, as well as the xylem vessels of the vasculature. In the case of the type III mutant, bacteria colonization was never detected in the xylem vessel or apoplast, though they freely enter the xylem vessel through the wound. After 9 days post inoculation with XccMAFF106712, the xylem vessel became filled with bacterial aggregates. This suggests that Xcc colonization can be divided into main four steps, (1) movement in the xylem vessel, (2) movement to the next cell, (3) adhesion to the host plant cells, and (4) formation of bacterial aggregates. The type III mutant abolished at least steps (1) and (2). Better understanding of Xcc colonization is essential for development of novel control techniques for black rot. PMID:24736478

  1. Real time live imaging of phytopathogenic bacteria Xanthomonas campestris pv. campestris MAFF106712 in 'plant sweet home'.

    PubMed

    Akimoto-Tomiyama, Chiharu; Furutani, Ayako; Ochiai, Hirokazu

    2014-01-01

    Xanthomonas is one of the most widespread phytobacteria, causing diseases on a variety of agricultural plants. To develop novel control techniques, knowledge of bacterial behavior inside plant cells is essential. Xanthomonas campestris pv. campestris, a vascular pathogen, is the causal agent of black rot on leaves of Brassicaceae, including Arabidopsis thaliana. Among the X. campestris pv. campestris stocks in the MAFF collection, we selected XccMAFF106712 as a model compatible pathogen for the A. thaliana reference ecotype Columbia (Col-0). Using modified green fluorescent protein (AcGFP) as a reporter, we observed real time XccMAFF106712 colonization in planta with confocal microscopy. AcGFP-expressing bacteria colonized the inside of epidermal cells and the apoplast, as well as the xylem vessels of the vasculature. In the case of the type III mutant, bacteria colonization was never detected in the xylem vessel or apoplast, though they freely enter the xylem vessel through the wound. After 9 days post inoculation with XccMAFF106712, the xylem vessel became filled with bacterial aggregates. This suggests that Xcc colonization can be divided into main four steps, (1) movement in the xylem vessel, (2) movement to the next cell, (3) adhesion to the host plant cells, and (4) formation of bacterial aggregates. The type III mutant abolished at least steps (1) and (2). Better understanding of Xcc colonization is essential for development of novel control techniques for black rot.

  2. Decommissioning of U.S. uranium production facilities

    SciTech Connect

    Not Available

    1995-02-01

    From 1980 to 1993, the domestic production of uranium declined from almost 44 million pounds U{sub 3}O{sub 8} to about 3 million pounds. This retrenchment of the U.S. uranium industry resulted in the permanent closing of many uranium-producing facilities. Current low uranium prices, excess world supply, and low expectations for future uranium demand indicate that it is unlikely existing plants will be reopened. Because of this situation, these facilities eventually will have to be decommissioned. The Uranium Mill Tailings and Radiation Control Act of 1978 (UMTRCA) vests the U.S. Environmental Protection Agency (EPA) with overall responsibility for establishing environmental standards for decommissioning of uranium production facilities. UMTRCA also gave the U.S. Nuclear Regulatory Commission (NRC) the responsibility for licensing and regulating uranium production and related activities, including decommissioning. Because there are many issues associated with decommissioning-environmental, political, and financial-this report will concentrate on the answers to three questions: (1) What is required? (2) How is the process implemented? (3) What are the costs? Regulatory control is exercised principally through the NRC licensing process. Before receiving a license to construct and operate an uranium producing facility, the applicant is required to present a decommissioning plan to the NRC. Once the plan is approved, the licensee must post a surety to guarantee that funds will be available to execute the plan and reclaim the site. This report by the Energy Information Administration (EIA) represents the most comprehensive study on this topic by analyzing data on 33 (out of 43) uranium production facilities located in Colorado, Nebraska, New Mexico, South Dakota, Texas, Utah, and Washington.

  3. Process for electrolytically preparing uranium metal

    DOEpatents

    Haas, Paul A.

    1989-08-01

    A process for making uranium metal from uranium oxide by first fluorinating uranium oxide to form uranium tetrafluoride and next electrolytically reducing the uranium tetrafluoride with a carbon anode to form uranium metal and CF.sub.4. The CF.sub.4 is reused in the fluorination reaction rather than being disposed of as a hazardous waste.

  4. Process for electrolytically preparing uranium metal

    DOEpatents

    Haas, Paul A.

    1989-01-01

    A process for making uranium metal from uranium oxide by first fluorinating uranium oxide to form uranium tetrafluoride and next electrolytically reducing the uranium tetrafluoride with a carbon anode to form uranium metal and CF.sub.4. The CF.sub.4 is reused in the fluorination reaction rather than being disposed of as a hazardous waste.

  5. Influence of uranium hydride oxidation on uranium metal behaviour

    SciTech Connect

    Patel, N.; Hambley, D.; Clarke, S.A.; Simpson, K.

    2013-07-01

    This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)

  6. Plant seed species identification from chemical fingerprints: a high-throughput application of direct analysis in real time mass spectrometry.

    PubMed

    Lesiak, Ashton D; Cody, Robert B; Dane, A John; Musah, Rabi A

    2015-09-01

    Plant species identification based on the morphological features of plant parts is a well-established science in botany. However, species identification from seeds has largely been unexplored, despite the fact that the seeds contain all of the genetic information that distinguishes one plant from another. Using seeds of genus Datura plants, we show here that the mass spectrum-derived chemical fingerprints for seeds of the same species are similar. On the other hand, seeds from different species within the same genus display distinct chemical signatures, even though they may contain similar characteristic biomarkers. The intraspecies chemical signature similarities on the one hand, and interspecies fingerprint differences on the other, can be processed by multivariate statistical analysis methods to enable rapid species-level identification and differentiation. The chemical fingerprints can be acquired rapidly and in a high-throughput manner by direct analysis in real time mass spectrometry (DART-MS) analysis of the seeds in their native form, without use of a solvent extract. Importantly, knowledge of the identity of the detected molecules is not required for species level identification. However, confirmation of the presence within the seeds of various characteristic tropane and other alkaloids, including atropine, scopolamine, scopoline, tropine, tropinone, and tyramine, was accomplished by comparison of the in-source collision-induced dissociation (CID) fragmentation patterns of authentic standards, to the fragmentation patterns observed in the seeds when analyzed under similar in-source CID conditions. The advantages, applications, and implications of the chemometric processing of DART-MS derived seed chemical signatures for species level identification and differentiation are discussed.

  7. US Transuranium and Uranium Registries case study on accidental exposure to uranium hexafluoride.

    PubMed

    Avtandilashvili, Maia; Puncher, Matthew; McComish, Stacey L; Tolmachev, Sergei Y

    2015-03-01

    The United States Transuranium and Uranium Registries' (USTUR) whole-body donor (Case 1031) was exposed to an acute inhalation of uranium hexafluoride (UF6) produced from an explosion at a uranium processing plant 65 years prior to his death. The USTUR measurements of tissue samples collected at the autopsy indicated long-term retention of inhaled slightly enriched uranium material (0.85% (235)U) in the deep lungs and thoracic lymph nodes. In the present study, the authors combined the tissue measurement results with historical bioassay data, and analysed them with International Commission on Radiological Protection (ICRP) respiratory tract models and the ICRP Publication 69 systemic model for uranium using maximum likelihood and Bayesian statistical methods. The purpose of the analysis was to estimate intakes and model parameter values that best describe the data, and evaluate their effect on dose assessment. The maximum likelihood analysis, which used the ICRP Publication 66 human respiratory tract model, resulted in a point estimate of 79 mg of uranium for the occupational intake composed of 86% soluble, type F material and 14% insoluble, type S material. For the Bayesian approach, the authors applied the Markov Chain Monte Carlo method, but this time used the revised human respiratory tract model, which is currently being used by ICRP to calculate new dose coefficients for workers. The Bayesian analysis estimated that the mean uranium intake was 160 mg, and calculated the case-specific lung dissolution parameters with their associated uncertainties. The parameters were consistent with the inhaled uranium material being predominantly soluble with a small but significant insoluble component. The 95% posterior range of the rapid dissolution fraction (the fraction of deposited material that is absorbed to blood rapidly) was 0.12 to 0.91 with a median of 0.37. The remaining fraction was absorbed slowly, with a 95% range of 0.000 22 d(-1) to 0.000 36

  8. Neural-net based real-time economic dispatch for thermal power plants

    SciTech Connect

    Djukanovic, M.; Milosevic, B.; Calovic, M.; Sobajic, D.J.

    1996-12-01

    This paper proposes the application of artificial neural networks to real-time optimal generation dispatch of thermal units. The approach can take into account the operational requirements and network losses. The proposed economic dispatch uses an artificial neural network (ANN) for generation of penalty factors, depending on the input generator powers and identified system load change. Then, a few additional iterations are performed within an iterative computation procedure for the solution of coordination equations, by using reference-bus penalty-factors derived from the Newton-Raphson load flow. A coordination technique for environmental and economic dispatch of pure thermal systems, based on the neural-net theory for simplified solution algorithms and improved man-machine interface is introduced. Numerical results on two test examples show that the proposed algorithm can efficiently and accurately develop optimal and feasible generator output trajectories, by applying neural-net forecasts of system load patterns.

  9. Accumulation of Metals and Boron in Phragmites australis Planted in Constructed Wetlands Polishing Real Electroplating Wastewater.

    PubMed

    Sochacki, Adam; Guy, Bernard; Faure, Olivier; Surmacz-Górska, Joanna

    2015-01-01

    The concentration of metals (Al, Cu, Fe, Mn, Ni, Zn) and B were determined in the above- and belowground biomass of Phragmites australis collected from the microcosm constructed wetland system used for the polishing of real electroplating wastewater. Translocation factor and bioconcentration factor were determined. Pearson correlation test was used to determine correlation between metal concentration in substrate and above- and belowground parts of Phragmites australis. The obtained results suggested that Phragmites australis did not play a major role as an accumulator of metals. It was observed also that the substrate could have exerted an effect on the translocation of Ni, Cu, Zn and Mn. The analysed concentrations of metals and B in biomass were in the range or even below the concentrations reported in the literature with the exception of Ni. The aboveground biomass was found suitable as a composting input in terms of metals concentrations.

  10. [Contrast study on natural radioactive nuclides contents of rice between Xiangshan uranium deposit area, Jiangxi and non-uranium depsoit area].

    PubMed

    Liu, Ping-Hui; Ye, Chang-Sheng; Xie, Shu-Rong; Rui, Yu-Kui

    2009-07-01

    The contents of natural radioactive nuclides such as uranium and thorium in paddies were analyzed and compared by means of ICP-MS. Totally 14 paddy samples were distinguished into two groups and collected from two rice planting area. One group (12 paddy samples) was collected from the Xiangshan uranium deposit area, Jiangxi province; while the other group (2 samples) collected from non-uranium deposit suburban area of Fuzhou city, Jiangxi, as comparison samples. The distance between the two sampling areas is about 80 kilometers. Before analysis, those paddy samples were continuously carbonized by two hours first, then continuously incinerated for 8 hours at the temperature of 600 degrees centigrade. The results show that the uranium contents in the paddy ash of samples gotten from Xiangshan uranium deposit area range from 0.053 to 1.482 microg x g(-1). The uranium contents of two comparison paddy samples ash are 0.059 and 0.061 microg x g(-1), respectiovely. The average uranium content of paddy ash of uranium deposit area is 0.323 microg x g(-1). Compared with the comparison samples, the uranium contents of paddy ash of uranium deposit area are considerably high, 5.30 times that of non-uranium deposit area. The thorium contents in paddy ash of the uranium deposit area, however, are relatively low and less than that of samples collected from non-uranium deposit area, which range from 0.029 to 0.311 microg x g(-1); The average level is 0.104 microg x g(-1), only about 50% of that of paddy ash sampled from non-urnaium deposit area. Moreover, there is significant linearity correlation between uranium and thorium contents of paddy sampled from Xiangshan uranium deposit area. The positive effects show that the thorium contents of paddy increase as uranium contents of paddy in uranium deposit area increase. The causes for the remarkable difference in uranium contents in paddy between urianium deposit area and non-uranium deposit area are not clear yet. The research on

  11. Laser melting of uranium carbides

    NASA Astrophysics Data System (ADS)

    Utton, C. A.; De Bruycker, F.; Boboridis, K.; Jardin, R.; Noel, H.; Guéneau, C.; Manara, D.

    2009-03-01

    In the context of the material research aimed at supporting the development of nuclear plants of the fourth Generation, renewed interest has recently arisen in carbide fuels. A profound understanding of the behaviour of nuclear materials in extreme conditions is of prime importance for the analysis of the operation limits of nuclear fuels, and prediction of possible nuclear reactor accidents. In this context, the main goal of the present paper is to demonstrate the feasibility of laser induced melting experiments on stoichiometric uranium carbides; UC, UC1.5 and UC2. Measurements were performed, at temperatures around 3000 K, under a few bars of inert gas in order to minimise vaporisation and oxidation effects, which may occur at these temperatures. Moreover, a recently developed investigation method has been employed, based on in situ analysis of the sample surface reflectivity evolution during melting. Current results, 2781 K for the melting point of UC, 2665 K for the solidus and 2681 K for the liquidus of U2C3, 2754 K for the solidus and 2770 K for the liquidus of UC2, are in fair agreement with early publications where the melting behaviour of uranium carbides was investigated by traditional furnace melting methods. Further information has been obtained in the current research about the non-congruent (solidus-liquidus) melting of certain carbides, which suggest that a solidus-liquidus scheme is followed by higher ratio carbides, possibly even for UC2.

  12. Mortality (1968-2008) in a French cohort of uranium enrichment workers potentially exposed to rapidly soluble uranium compounds.

    PubMed

    Zhivin, Sergey; Guseva Canu, Irina; Samson, Eric; Laurent, Olivier; Grellier, James; Collomb, Philippe; Zablotska, Lydia B; Laurier, Dominique

    2016-03-01

    Until recently, enrichment of uranium for civil and military purposes in France was carried out by gaseous diffusion using rapidly soluble uranium compounds. We analysed the relationship between exposure to soluble uranium compounds and exposure to external γ-radiation and mortality in a cohort of 4688 French uranium enrichment workers who were employed between 1964 and 2006. Data on individual annual exposure to radiological and non-radiological hazards were collected for workers of the AREVA NC, CEA and Eurodif uranium enrichment plants from job-exposure matrixes and external dosimetry records, differentiating between natural, enriched and depleted uranium. Cause-specific mortality was compared with the French general population via standardised mortality ratios (SMR), and was analysed via Poisson regression using log-linear and linear excess relative risk models. Over the period of follow-up, 131 161 person-years at risk were accrued and 21% of the subjects had died. A strong healthy worker effect was observed: all causes SMR=0.69, 95% CI 0.65 to 0.74. SMR for pleural cancer was significantly increased (2.3, 95% CI 1.06 to 4.4), but was only based on nine cases. Internal uranium and external γ-radiation exposures were not significantly associated with any cause of mortality. This is the first study of French uranium enrichment workers. Although limited in statistical power, further follow-up of this cohort, estimation of internal uranium doses and pooling with similar cohorts should elucidate potential risks associated with exposure to soluble uranium compounds. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  13. 5. VIEW OF THE FOUNDRY. IN THE FOUNDRY, ENRICHED URANIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. VIEW OF THE FOUNDRY. IN THE FOUNDRY, ENRICHED URANIUM WAS CAST INTO SLABS OR INGOTS FROM WHICH WEAPONS COMPONENTS WERE FABRICATED. (4/4/66) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

  14. 4. VIEW OF THE FOUNDRY. IN THE FOUNDRY, ENRICHED URANIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. VIEW OF THE FOUNDRY. IN THE FOUNDRY, ENRICHED URANIUM WAS CAST INTO SLABS OR INGOTS FROM WHICH WEAPONS COMPONENTS WERE FABRICATED. (5/17/62). - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

  15. METHOD OF RECOVERING URANIUM COMPOUNDS

    DOEpatents

    Poirier, R.H.

    1957-10-29

    S>The recovery of uranium compounds which have been adsorbed on anion exchange resins is discussed. The uranium and thorium-containing residues from monazite processed by alkali hydroxide are separated from solution, and leached with an alkali metal carbonate solution, whereby the uranium and thorium hydrorides are dissolved. The carbonate solution is then passed over an anion exchange resin causing the uranium to be adsorbed while the thorium remains in solution. The uranium may be recovered by contacting the uranium-holding resin with an aqueous ammonium carbonate solution whereby the uranium values are eluted from the resin and then heating the eluate whereby carbon dioxide and ammonia are given off, the pH value of the solution is lowered, and the uranium is precipitated.

  16. Microbial reduction of uranium

    USGS Publications Warehouse

    Lovley, D.R.; Phillips, E.J.P.; Gorby, Y.A.; Landa, E.R.

    1991-01-01

    REDUCTION of the soluble, oxidized form of uranium, U(VI), to insoluble U(IV) is an important mechanism for the immobilization of uranium in aquatic sediments and for the formation of some uranium ores1-10. U(VI) reduction has generally been regarded as an abiological reaction in which sulphide, molecular hydrogen or organic compounds function as the reductant1,2,5,11. Microbial involvement in U(VI) reduction has been considered to be limited to indirect effects, such as microbial metabolism providing the reduced compounds for abiological U(VI) reduction and microbial cell walls providing a surface to stimulate abiological U(VI) reduction1,12,13. We report here, however, that dissimilatory Fe(III)-reducing microorganisms can obtain energy for growth by electron transport to U(VI). This novel form of microbial metabolism can be much faster than commonly cited abiological mechanisms for U(VI) reduction. Not only do these findings expand the known potential terminal electron acceptors for microbial energy transduction, they offer a likely explanation for the deposition of uranium in aquatic sediments and aquifers, and suggest a method for biological remediation of environments contaminated with uranium.

  17. PRODUCTION OF URANIUM HEXAFLUORIDE

    DOEpatents

    Fowler, R.D.

    1957-08-27

    A process for the production of uranium hexafluoride from the oxides of uranium is reported. In accordance with the method, the higher oxides of uranium may be reduced to uranium dioxide (UO/sub 2/), the latter converted into uranium tetrafluoride by reaction with hydrogen fluoride, and the UF/sub 4/ converted to UF/sub 6/ by reaction with a fluorinating agent, such as CoF/sub 3/. The UO/sub 3/ or U/sub 3/O/sub 8/ is placed in a reac tion chamber in a copper boat or tray enclosed in a copper oven, and heated to 500 to 650 deg C while hydrogen gas is passed through the oven. After nitrogen gas is used to sweep out the hydrogen and the water vapor formed, and while continuing to inaintain the temperature between 400 deg C and 600 deg C, anhydrous hydrogen fluoride is passed through. After completion of the conversion of UO/sub 2/ to UF/sub 4/ the temperature of the reaction chamber is lowered to about 400 deg C or less, the UF/sub 4/ is mixed with the requisite quantity of CoF/sub 3/, and after evacuating the chamber, the mixture is heated to 300 to 400 deg C, and the resulting UF/sub 6/ is led off and delivered to a condenser.

  18. Uranium (VI) solubility in carbonate-free ERDA-6 brine

    SciTech Connect

    Lucchini, Jean-francois; Khaing, Hnin; Reed, Donald T

    2010-01-01

    When present, uranium is usually an element of importance in a nuclear waste repository. In the Waste Isolation Pilot Plant (WIPP), uranium is the most prevalent actinide component by mass, with about 647 metric tons to be placed in the repository. Therefore, the chemistry of uranium, and especially its solubility in the WIPP conditions, needs to be well determined. Long-term experiments were performed to measure the solubility of uranium (VI) in carbonate-free ERDA-6 brine, a simulated WIPP brine, at pC{sub H+} values between 8 and 12.5. These data, obtained from the over-saturation approach, were the first repository-relevant data for the VI actinide oxidation state. The solubility trends observed pointed towards low uranium solubility in WIPP brines and a lack of amphotericity. At the expected pC{sub H+} in the WIPP ({approx} 9.5), measured uranium solubility approached 10{sup -7} M. The objective of these experiments was to establish a baseline solubility to further investigate the effects of carbonate complexation on uranium solubility in WIPP brines.

  19. Real-time Assay of Toxic Lead in In Vivo Living Plant Tissue

    PubMed Central

    Kim, Nack Joo; Youn, Minsang; Kim, Yongwook; Sung, Yeolmin; Kim, Dohoon

    2013-01-01

    A method of detecting lead was developed using square wave anodic stripping voltammetry (SWASV) with DNA-carbon nanotube paste electrode (CNTPE). The results indicated a sensitive oxidation peak current of lead on the DNA-CNTPE. The curves were obtained within a concentration range of 50 ngL−1-20 mgL−1 with preconcentration time of 100, 200, and 400 sec at the concentration of mgL−1, μgL−1, and ngL−1, respectively. The observed relative standard deviation was 0.101% (n = 12) in the lead concentration of 30.0 μgL−1 under optimum conditions. The low detection limit (S/N) was pegged at 8 ngL−1 (2.6 × 10−8 M). Results showed that the developed method can be used in real-time assay in vivo without requiring any pretreatment and pharmaceutical samples, and food samples, as well as other materials requiring water source contamination analyses. PMID:24578800

  20. Magnesium reduction of uranium oxide

    SciTech Connect

    Elliott, G.R.B.

    1985-08-13

    A method and apparatus are provided for reducing uranium oxide with magnesium to form uranium metal. The reduction is carried out in a molten-salt solution of density greater than 3.4 grams per cubic centimeter, thereby allowing the uranium product to sink and the magnesium oxide byproduct to float, consequently allowing separation of product and byproduct.

  1. Uranium immobilization and nuclear waste

    SciTech Connect

    Duffy, C.J.; Ogard, A.E.

    1982-02-01

    Considerable information useful in nuclear waste storage can be gained by studying the conditions of uranium ore deposit formation. Further information can be gained by comparing the chemistry of uranium to nuclear fission products and other radionuclides of concern to nuclear waste disposal. Redox state appears to be the most important variable in controlling uranium solubility, especially at near neutral pH, which is characteristic of most ground water. This is probably also true of neptunium, plutonium, and technetium. Further, redox conditions that immobilize uranium should immobilize these elements. The mechanisms that have produced uranium ore bodies in the Earth's crust are somewhat less clear. At the temperatures of hydrothermal uranium deposits, equilibrium models are probably adequate, aqueous uranium (VI) being reduced and precipitated by interaction with ferrous-iron-bearing oxides and silicates. In lower temperature roll-type uranium deposits, overall equilibrium may not have been achieved. The involvement of sulfate-reducing bacteria in ore-body formation has been postulated, but is uncertain. Reduced sulfur species do, however, appear to be involved in much of the low temperature uranium precipitation. Assessment of the possibility of uranium transport in natural ground water is complicated because the system is generally not in overall equilibrium. For this reason, Eh measurements are of limited value. If a ground water is to be capable of reducing uranium, it must contain ions capable of reducing uranium both thermodynamically and kinetically. At present, the best candidates are reduced sulfur species.

  2. PROCESS OF PREPARING URANIUM CARBIDE

    DOEpatents

    Miller, W.E.; Stethers, H.L.; Johnson, T.R.

    1964-03-24

    A process of preparing uranium monocarbide is de scribed. Uranium metal is dissolved in cadmium, zinc, cadmium-- zinc, or magnesium-- zinc alloy and a small quantity of alkali metal is added. Addition of stoichiometric amounts of carbon at 500 to 820 deg C then precipitates uranium monocarbide. (AEC)

  3. Reference genes for quantitative real-time polymerase chain reaction studies in soybean plants under hypoxic conditions.

    PubMed

    Nakayama, T J; Rodrigues, F A; Neumaier, N; Marcelino-Guimarães, F C; Farias, J R B; de Oliveira, M C N; Borém, A; de Oliveira, A C B; Emygdio, B M; Nepomuceno, A L

    2014-02-13

    Quantitative real-time polymerase chain reaction (RT-qPCR) is a powerful tool used to measure gene expression. However, because of its high sensitivity, the method is strongly influenced by the quality and concentration of the template cDNA and by the amplification efficiency. Relative quantification is an effective strategy for correcting random and systematic errors by using the expression level of reference gene(s) to normalize the expression level of the genes of interest. To identify soybean reference genes for use in studies of flooding stress, we compared 5 candidate reference genes (CRGs) with the NormFinder and GeNorm programs to select the best internal control. The expression stability of the CRGs was evaluated in root tissues from soybean plants subjected to hypoxic conditions. Elongation factor 1-beta and actin-11 were identified as the most appropriate genes for RT-qPCR normalization by both the NormFinder and GeNorm analyses. The expression profiles of the genes for alcohol dehydrogenase 1, sucrose synthase 4, and ascorbate peroxidase 2 were analyzed by comparing different normalizing combinations (including no normalization) of the selected reference genes. Here, we have identified potential genes for use as references for RT-qPCR normalization in experiments with soybean roots growing in O2-depleted environments, such as flooding-stressed plants.

  4. PROCESS FOR RECOVERING URANIUM

    DOEpatents

    MacWood, G.E.; Wilder, C.D.; Altman, D.

    1959-03-24

    A process is described for recovering uranium from deposits on stainless steel liner surfaces of calutrons. The deposit is removed from the stainless steel surface by washing with aqueous nitric acid. The solution obtained containing uranium, chromium, nickels copper, and iron is treated with excess of ammonium hydroxide to precipitatc the uranium, irons and chromium and convert thc nickel and copper to soluble ammonia complexions. The precipitated material is removed, dried, and treated with carbon tetrachloride at an elevated temperature of about 500 to 600 deg C to form a vapor mixture of UCl/sub 4/, UCl/sub 5/, FeCl/ sub 3/, and CrCl/sub 4/. The UCl/sub 4/ is separated from this vapor mixture by selective fractional condensation at a temprrature of about 300 to400 deg C.

  5. Process for recovering uranium

    DOEpatents

    MacWood, G. E.; Wilder, C. D.; Altman, D.

    1959-03-24

    A process useful in recovering uranium from deposits on stainless steel liner surfaces of calutrons is presented. The deposit is removed from the stainless steel surface by washing with aqueous nitric acid. The solution obtained containing uranium, chromium, nickel, copper, and iron is treated with an excess of ammonium hydroxide to precipitnte the uranium, iron, and chromium and convert the nickel and copper to soluble ammonio complexions. The precipitated material is removed, dried and treated with carbon tetrachloride at an elevated temperature of about 500 to 600 deg C to form a vapor mixture of UCl/ sub 4/, UCl/sub 5/, FeCl/sub 3/, and CrCl/sub 4/. The UCl/sub 4/ is separated from this vapor mixture by selective fractional condensation at a temperature of about 500 to 400 deg C.

  6. EXTRACTION OF URANIUM

    DOEpatents

    Kesler, R.D.; Rabb, D.D.

    1959-07-28

    An improved process is presented for recovering uranium from a carnotite ore. In the improved process U/sub 2/O/sub 5/ is added to the comminuted ore along with the usual amount of NaCl prior to roasting. The amount of U/sub 2/O/ sub 5/ is dependent on the amount of free calcium oxide and the uranium in the ore. Specifically, the desirable amount of U/sub 2/O/sub 5/ is 3.2% for each 1% of CaO, and 5 to 6% for each 1% of uranium. The mixture is roasted at about 1560 deg C for about 30 min and then leached with a 3 to 9% aqueous solution of sodium carbonate.

  7. PROCESS FOR PRODUCING URANIUM HALIDES

    DOEpatents

    Murphree, E.V.

    1957-10-29

    A process amd associated apparatus for producing UF/sub 4/ from U/sub 3/ O/sub 8/ by a fluidized'' technique are reported. The U/sub 3/O/sub 8/ is first reduced to UO/sub 2/ by reaction with hydrogen, and the lower oxide of uranium is then reacted with gaseous HF to produce UF/sub 4/. In each case the reactant gas is used, alone or in combination with inert gases, to fluidize'' the finely divided reactant solid. The complete setup of the plant equipment including bins, reactor and the associated piping and valving, is described. An auxiliary fluorination reactor allows for the direct production of UF/sub 6/ from UF/sub 4/ and fluorine gas, or if desired, UF/sub 4/ may be collected as the product.

  8. The utilization of uranium industry technology and relevant chemistry to leach uranium from mixed-waste solids

    SciTech Connect

    Mattus, A.J.; Farr, L.L.

    1991-01-01

    Methods for the chemical extraction of uranium from a number of refractory uranium-containing minerals found in nature have been in place and employed by the uranium mining and milling industry for nearly half a century. These same methods, in conjunction with the principles of relevant uranium chemistry, have been employed at the Oak Ridge National Laboratory (ORNL) to chemically leach depleted uranium from mixed-waste sludge and soil. The removal of uranium from what is now classified as mixed waste may result in the reclassification of the waste as hazardous, which may then be delisted. The delisted waste might eventually be disposed of in commercial landfill sites. This paper generally discusses the application of chemical extractive methods to remove depleted uranium from a biodenitrification sludge and a storm sewer soil sediment from the Y-12 weapons plant in Oak Ridge. Some select data obtained from scoping leach tests on these materials are presented along with associated limitations and observations which might be useful to others performing such test work. 6 refs., 2 tabs.

  9. Agriculture in an area impacted by past uranium mining activities

    SciTech Connect

    Carvalho, F. P.; Oliveira, J. M.; Neves, O.; Vicente, E. M.; Abreu, M. M.

    2007-07-01

    The shallow aquifer near the old Cunha Baixa uranium mine (Viseu, Portugal) was contaminated by acid mine drainage. Concentration of radionuclides in water from irrigation wells and in the topsoil layer of the agriculture fields nearby display enhanced concentrations of uranium, radium and polonium. Two types of agriculture land in this area were selected, one with enhanced and another with low uranium concentrations, for controlled growth of lettuce and potatoes. Plants were grown in replicate portions of land (two plots) in each soil type and were periodically irrigated with water from wells. In each soil, one plot was irrigated with water containing low concentration of dissolved uranium and the other plot with water containing enhanced concentration of dissolved uranium. At the end of the growth season, plants were harvested and analysed, along with soil and irrigation water samples. Results show the accumulation of radionuclides in edible parts of plants, specially in the field plots with higher radionuclide concentrations in soil. Radionuclides in irrigation water contributed less to the radioactivity accumulated in plants than radionuclides from soils. (authors)

  10. PROCESS OF RECOVERING URANIUM

    DOEpatents

    Price, T.D.; Jeung, N.M.

    1958-06-17

    An improved precipitation method is described for the recovery of uranium from aqueous solutions. After removal of all but small amounts of Ni or Cu, and after complexing any iron present, the uranium is separated as the peroxide by adding H/sub 2/O/sub 2/. The improvement lies in the fact that the addition of H/sub 2/O/sub 2/ and consequent precipitation are carried out at a temperature below the freezing; point of the solution, so that minute crystals of solvent are present as seed crystals for the precipitation.

  11. PRODUCTION OF URANIUM TUBING

    DOEpatents

    Creutz, E.C.

    1958-04-15

    The manufacture of thin-walled uranium tubing by the hot-piercing techique is described. Uranium billets are preheated to a temperature above 780 d C. The heated billet is fed to a station where it is engaged on its external surface by three convex-surfaced rotating rollers which are set at an angle to the axis of the billet to produce a surface friction force in one direction to force the billet over a piercing mandrel. While being formed around the mandrel and before losing the desired shape, the tube thus formed is cooled by a water spray.

  12. Corrosion-resistant uranium

    DOEpatents

    Hovis, Jr., Victor M.; Pullen, William C.; Kollie, Thomas G.; Bell, Richard T.

    1983-01-01

    The present invention is directed to the protecting of uranium and uranium alloy articles from corrosion by providing the surfaces of the articles with a layer of an ion-plated metal selected from aluminum and zinc to a thickness of at least 60 microinches and then converting at least the outer surface of the ion-plated layer of aluminum or zinc to aluminum chromate or zinc chromate. This conversion of the aluminum or zinc to the chromate form considerably enhances the corrosion resistance of the ion plating so as to effectively protect the coated article from corrosion.

  13. TREATMENT OF URANIUM SURFACES

    DOEpatents

    Slunder, C.J.

    1959-02-01

    An improved process is presented for prcparation of uranium surfaces prior to electroplating. The surfacc of the uranium to be electroplated is anodized in a bath comprising a solution of approximately 20 to 602 by weight of phosphoric acid which contains about 20 cc per liter of concentrated hydrochloric acid. Anodization is carried out for approximately 20 minutes at a current density of about 0.5 amperes per square inch at a temperature of about 35 to 45 C. The oxidic film produced by anodization is removed by dipping in strong nitric acid, followed by rinsing with water just prior to electroplating.

  14. Recovery of Uranium Fragments

    NASA Astrophysics Data System (ADS)

    James, H. R.; McElrue, D. H.; Winter, R. E.

    2002-07-01

    We describe a theory for calculating the penetration of fragments into foam. Comparisons with regular projectiles show that the drag term is similar in value to the analogous term in aerodynamics. This, plus the simple model used to describe porosity, enables the theory to be used in predicting the levels of stress present when uranium fragments are arrested in foam catchers. Consequently the theory can be used to assist in the design of catchers which will not distort uranium fragments travelling at 1-3 km/s. The theory is tested against experiments using some current designs.

  15. Corrosion-resistant uranium

    DOEpatents

    Hovis, V.M. Jr.; Pullen, W.C.; Kollie, T.G.; Bell, R.T.

    1981-10-21

    The present invention is directed to the protecting of uranium and uranium alloy articles from corrosion by providing the surfaces of the articles with a layer of an ion-plated metal selected from aluminum and zinc to a thickness of at least 60 microinches and then converting at least the outer surface of the ion-plated layer of aluminum or zinc to aluminum chromate or zinc chromate. This conversion of the aluminum or zinc to the chromate form considerably enhances the corrosion resistance of the ion plating so as to effectively protect the coated article from corrosion.

  16. PREPARATION OF URANIUM TRIOXIDE

    DOEpatents

    Buckingham, J.S.

    1959-09-01

    The production of uranium trioxide from aqueous solutions of uranyl nitrate is discussed. The uranium trioxide is produced by adding sulfur or a sulfur-containing compound, such as thiourea, sulfamic acid, sulfuric acid, and ammonium sulfate, to the uranyl solution in an amount of about 0.5% by weight of the uranyl nitrate hexahydrate, evaporating the solution to dryness, and calcining the dry residue. The trioxide obtained by this method furnished a dioxide with a considerably higher reactivity with hydrogen fluoride than a trioxide prepared without the sulfur additive.

  17. Germylmercury complex of uranium

    SciTech Connect

    Bochkarev, M.N.; Bochkarev, L.N.; Kalinina, G.S.; Razuvaev, G.A.; Sevast'yanov, V.G.

    1983-09-01

    The authors have established that metallic uranium reacts with ((C/sub 6/F/sub 5/)/sub 3/Ge)/sub 3/Hg at about 20/sup 0/C in a medium of 1,2-dimethoxyethane (DME). The reaction was complete after 3 h by the separation of metallic mercury (100 %) and by the formation of the heptakis (tris(pentafluoro-phenyl)germyl) dimercurate of uranium (((C/sub 6/F/sub 5/)/sub 3/Ge)/sub 7/Hg/sub 2/)U3DME (i), 81%. 1 reference.

  18. METHOD OF ELECTROPOLISHING URANIUM

    DOEpatents

    Walker, D.E.; Noland, R.A.

    1959-07-14

    A method of electropolishing the surface of uranium articles is presented. The process of this invention is carried out by immersing the uranium anticle into an electrolyte which contains from 35 to 65% by volume sulfuric acid, 1 to 20% by volume glycerine and 25 to 50% by volume of water. The article is made the anode in the cell and polished by electrolyzing at a voltage of from 10 to 15 volts. Discontinuing the electrolysis by intermittently withdrawing the anode from the electrolyte and removing any polarized film formed therein results in an especially bright surface.

  19. RECOVERY OF URANIUM FROM PITCHBLENDE

    DOEpatents

    Ruehle, A.E.

    1958-06-24

    The decontamination of uranium from molybdenum is described. When acid solutions containing uranyl nitrate are contacted with ether for the purpose of extracting the uranium values, complex molybdenum compounds are coextracted with the uranium and also again back-extracted from the ether with the uranium. This invention provides a process for extracting uranium in which coextraction of molybdenum is avoided. It has been found that polyhydric alcohols form complexes with molybdenum which are preferentially water-soluble are taken up by the ether extractant to only a very minor degree. The preferred embodiment of the process uses mannitol, sorbitol or a mixture of the two as the complexing agent.

  20. High loading uranium fuel plate

    DOEpatents

    Wiencek, Thomas C.; Domagala, Robert F.; Thresh, Henry R.

    1990-01-01

    Two embodiments of a high uranium fuel plate are disclosed which contain a meat comprising structured uranium compound confined between a pair of diffusion bonded ductile metal cladding plates uniformly covering the meat, the meat having a uniform high fuel loading comprising a content of uranium compound greater than about 45 Vol. % at a porosity not greater than about 10 Vol. %. In a first embodiment, the meat is a plurality of parallel wires of uranium compound. In a second embodiment, the meat is a dispersion compact containing uranium compound. The fuel plates are fabricated by a hot isostatic pressing process.

  1. STRIPPING OF URANIUM FROM ORGANIC EXTRACTANTS

    DOEpatents

    Crouse, D.J. Jr.

    1962-09-01

    A liquid-liquid extraction method is given for recovering uranium values from uranium-containing solutions. Uranium is removed from a uranium-containing organic solution by contacting said organic solution with an aqueous ammonium carbonate solution substantially saturated in uranium values. A uranium- containing precipitate is thereby formed which is separated from the organic and aqueous phases. Uranium values are recovered from this separated precipitate. (AE C)

  2. Rhizofiltration using sunflower (Helianthus annuus L.) and bean (Phaseolus vulgaris L. var. vulgaris) to remediate uranium contaminated groundwater.

    PubMed

    Lee, Minhee; Yang, Minjune

    2010-01-15

    The uranium removal efficiencies of rhizofiltration in the remediation of groundwater were investigated in lab-scale experiments. Sunflower (Helianthus annuus L.) and bean (Phaseolus vulgaris L. var. vulgaris) were cultivated and an artificially uranium contaminated solution and three genuine groundwater samples were used in the experiments. More than 80% of the initial uranium in solution and genuine groundwater, respectively, was removed within 24h by using sunflower and the residual uranium concentration of the treated water was lower than 30 microg/L (USEPA drinking water limit). For bean, the uranium removal efficiency of the rhizofiltration was roughly 60-80%. The maximum uranium removal via rhizofiltration for the two plant cultivars occurred at pH 3-5 of solution and their uranium removal efficiencies exceeded 90%. The lab-scale continuous rhizofiltration clean-up system delivered over 99% uranium removal efficiency, and the results of SEM and EDS analyses indicated that most uranium accumulated in the roots of plants. The present results suggested that the uranium removal capacity of two plants evaluated in the clean-up system was about 25mg/kg of wet plant mass. Notably, the removal capacity of the root parts only was more than 500 mg/kg.

  3. Transfer of U, Al and Mn in the water-soil-plant (Solanum tuberosum L.) system near a former uranium mining area (Cunha Baixa, Portugal) and implications to human health.

    PubMed

    Neves, M O; Figueiredo, V R; Abreu, M M

    2012-02-01

    Knowledge about metals in crops, grown in contaminated soils around mine sites, is limited and concerns about exposure to hazardous elements through the consumption of contaminated foodstuff, are high. In this study a field experiment was carried out in two agricultural soils located near a former uranium mine area (Cunha Baixa, Portugal). The purpose of the study was to assess the effect of irrigation water quality on soil-potato (Solanum tuberosum L.) crop system and to evaluate if the consumption of the crop represents health risk to the local villagers. The soils were divided in two plots: one irrigated with contaminated water (U: 1.03-1.04mg/L; Al: 7.5-8.00mg/L; Mn: 4.52mg/L) and the other with uncontaminated water (U: 14-10μg/L; Al: 17-23μg/L; Mn: 2.4-5.7μg/L). After irrigation and potato growth, only soil characteristics, as salinity and total U and Mn concentrations were significantly different from those measured at the beginning of the experiment. Within the potato plants, elements were mostly translocated and concentrated in the aerial part: stems and leaves (U: 73-87%; Al: 85-96%; Mn: 85-94%), which minimize the risk of contamination of the edible tissue. In potato tubers, the highest average concentrations (121-590μg U/kg; 25-64mg Al/kg; 12-13mg Mn/kg dry weight) were registered at soil plots irrigated with contaminated water. Uranium and Al were mostly concentrated in the potato peel (88-96 and 76-85%, respectively), and Mn (67-78%) in the pulp, which reinforces the importance of removing peel to minimize human exposure. The risk analysis calculated for non-cancer health effects (hazard quotient), related only to the exposure through the consumption of this basic foodstuff, revealed safety for Cunha Baixa village residents (adults and children) even when potato crop was grown on U enriched soils and irrigated with contaminated water. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. 76 FR 60941 - Policy Regarding Submittal of Amendments for Processing of Equivalent Feed at Licensed Uranium...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-30

    ... holders of NRC operating licenses for water treatment; all companies that have submitted applications to... the intent of this RIS to change the policy expressed in RIS 00-23 or redefine the definition of... uranium at a facility other than a licensed uranium recovery facility, such as water treatment plants or...

  5. Fluid-bed fluoride volatility process recovers uranium from spent uranium alloy fuels

    NASA Technical Reports Server (NTRS)

    Barghusen, J. J.; Chilenskas, A. A.; Gunderson, G. E.; Holmes, J. T.; Jonke, A. A.; Kincinas, J. E.; Levitz, N. M.; Potts, G. L.; Ramaswami, D.; Stethers, H.; hide

    1967-01-01

    Fluid-bed fluoride volatility process recovers uranium from uranium fuels containing either zirconium or aluminum. The uranium is recovered as uranium hexafluoride. The process requires few operations in simple, compact equipment, and eliminates aqueous radioactive wastes.

  6. Uranium, soluble salts

    Integrated Risk Information System (IRIS)

    Uranium , soluble salts ; no CASRN Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  7. Uranium Reduction by Clostridia

    SciTech Connect

    Francis, A.J.; Dodge, Cleveland J.; Gillow, Jeffrey B.

    2006-04-05

    The FRC groundwater and sediment contain significant concentrations of U and Tc and are dominated by low pH, and high nitrate and Al concentrations where dissimilatory metal reducing bacterial activity may be limited. The presence of Clostridia in Area 3 at the FRC site has been confirmed and their ability to reduce uranium under site conditions will be determined. Although the phenomenon of uranium reduction by Clostridia has been firmly established, the molecular mechanisms underlying such a reaction are not very clear. The authors are exploring the hypothesis that U(VI) reduction occurs through hydrogenases and other enzymes (Matin and Francis). Fundamental knowledge of metal reduction using Clostridia will allow us to exploit naturally occurring processes to attenuate radionuclide and metal contaminants in situ in the subsurface. The outline for this report are as follows: (1) Growth of Clostridium sp. under normal culture conditions; (2) Fate of metals and radionuclides in the presence of Clostridia; (3) Bioreduction of uranium associated with nitrate, citrate, and lepidocrocite; and (4) Utilization of Clostridium sp. for immobilization of uranium at the FRC Area 3 site.

  8. URANIUM RECOVERY PROCESS

    DOEpatents

    Hyman, H.H.; Dreher, J.L.

    1959-07-01

    The recovery of uranium from the acidic aqueous metal waste solutions resulting from the bismuth phosphate carrier precipitation of plutonium from solutions of neutron irradiated uranium is described. The waste solutions consist of phosphoric acid, sulfuric acid, and uranium as a uranyl salt, together with salts of the fission products normally associated with neutron irradiated uranium. Generally, the process of the invention involves the partial neutralization of the waste solution with sodium hydroxide, followed by conversion of the solution to a pH 11 by mixing therewith sufficient sodium carbonate. The resultant carbonate-complexed waste is contacted with a titanated silica gel and the adsorbent separated from the aqueous medium. The aqueous solution is then mixed with sufficient acetic acid to bring the pH of the aqueous medium to between 4 and 5, whereby sodium uranyl acetate is precipitated. The precipitate is dissolved in nitric acid and the resulting solution preferably provided with salting out agents. Uranyl nitrate is recovered from the solution by extraction with an ether such as diethyl ether.

  9. URANIUM SOLVENT EXTRACTION PROCESS

    DOEpatents

    Harrington, C.D.

    1959-09-01

    A method is given for extracting uranium values from ores of high phosphate content consisting of dissolving them in aqueous nitric acid, adjusting the concentration of the aqueous solution to about 2 M with respect to nitric acid, and then contacting it with diethyl ether which has previously been made 1 M with respect to nitric acid.

  10. Uranium Location Database

    EPA Pesticide Factsheets

    A GIS compiled locational database in Microsoft Access of ~15,000 mines with uranium occurrence or production, primarily in the western United States. The metadata was cooperatively compiled from Federal and State agency data sets and enables the user to conduct geographic and analytical studies on mine impacts on the public and environment.

  11. The neurotoxicology of uranium.

    PubMed

    Dinocourt, Céline; Legrand, Marie; Dublineau, Isabelle; Lestaevel, Philippe

    2015-11-04

    The brain is a target of environmental toxic pollutants that impair cerebral functions. Uranium is present in the environment as a result of natural deposits and release by human applications. The first part of this review describes the passage of uranium into the brain, and its effects on neurological functions and cognitive abilities. Very few human studies have looked at its cognitive effects. Experimental studies show that after exposure, uranium can reach the brain and lead to neurobehavioral impairments, including increased locomotor activity, perturbation of the sleep-wake cycle, decreased memory, and increased anxiety. The mechanisms underlying these neurobehavioral disturbances are not clearly understood. It is evident that there must be more than one toxic mechanism and that it might include different targets in the brain. In the second part, we therefore review the principal mechanisms that have been investigated in experimental models: imbalance of the anti/pro-oxidant system and neurochemical and neurophysiological pathways. Uranium effects are clearly specific according to brain area, dose, and time. Nonetheless, this review demonstrates the paucity of data about its effects on developmental processes and the need for more attention to the consequences of exposure during development.

  12. Diffusion of uranium hexafluoride

    NASA Astrophysics Data System (ADS)

    Winkelmann, J.

    This document is part of Subvolume A `Gases in Gases, Liquids and their Mixtures' of Volume 15 `Diffusion in Gases, Liquids and Electrolytes' of Landolt-Börnstein Group IV `Physical Chemistry'. It is part of the chapter of the chapter `Diffusion in Pure Gases' and contains data on diffusion of uranium hexafluoride

  13. Real-Time Imaging of Plant Cell Wall Structure at Nanometer Scale, with Respect to Cellulase Accessibility and Degradation Kinetics (Presentation)

    SciTech Connect

    Ding, S. Y.

    2012-05-01

    Presentation on real-time imaging of plant cell wall structure at nanometer scale. Objectives are to develop tools to measure biomass at the nanometer scale; elucidate the molecular bases of biomass deconstruction; and identify factors that affect the conversion efficiency of biomass-to-biofuels.

  14. PRODUCTION OF URANIUM METAL BY CARBON REDUCTION

    DOEpatents

    Holden, R.B.; Powers, R.M.; Blaber, O.J.

    1959-09-22

    The preparation of uranium metal by the carbon reduction of an oxide of uranium is described. In a preferred embodiment of the invention a charge composed of carbon and uranium oxide is heated to a solid mass after which it is further heated under vacuum to a temperature of about 2000 deg C to produce a fused uranium metal. Slowly ccoling the fused mass produces a dendritic structure of uranium carbide in uranium metal. Reacting the solidified charge with deionized water hydrolyzes the uranium carbide to finely divide uranium dioxide which can be separated from the coarser uranium metal by ordinary filtration methods.

  15. Enrichment of uranium in particulate matter during litter decomposition affected by Gammarus pulex L.

    PubMed

    Schaller, Jörg; Weiske, Arndt; Mkandawire, Martin; Dudel, E Gert

    2008-12-01

    Plant litter and organic matter of aquatic sediments provide a significant sink of soluble inorganic uranium species in contaminated ecosystems. The uranium content in detritus has been observed to increase significantly during decomposition. However, the influence of the decomposer community on uranium fixation remains unclear. In view of this, we investigated the influence of a shredder (the freshwater shrimp Gammarus pulex L) on uranium fixation and mobilization during the degradation of plant litter. Leaf litter from Alnus glutinosa (L.) Gaertn. with 1152 mg kg(-1) U of dry biomass (DM) and without uranium was used in a 14-day laboratory experiment. The uranium concentration in the particulate organic material (POM) at the end of experiment was 1427 mg kg(-1) DM. After 14 days of decay, the residues of the leaves show a uranium concentration of 644 mg kg(-1) DM. Uranium concentrations in the media initially increased reaching up to 63.9 microg L(-1) but finally decreased to an average value of 34.3 microg L(-1). Atthe same time, DOC levels increased from 2.43 mg L(-1) up to 11.4 mg L(-1) in the course of the experiment Hence, inorganic uranium fixation onto particulate organic matter was enhanced by the activity of G. pulex.

  16. Use of tissue culture techniques for producing virus-free plant in garlic and their identification through real-time PCR.

    PubMed

    Taşkın, Hatıra; Baktemur, Gökhan; Kurul, Mehmet; Büyükalaca, Saadet

    2013-01-01

    This study was performed for comparison of meristem culture technique with shoot tip culture technique for obtaining virus-free plant, comparison of micropropagation success of two different nutrient media, and determination of effectiveness of real-time PCR assay for the detection of viruses. Two different garlic species (Allium sativum and Allium tuncelianum) and two different nutrient media were used in this experiment. Results showed that Medium 2 was more successful compared to Medium 1 for both A. tuncelianum and A. sativum (Kastamonu garlic clone). In vitro plants obtained via meristem and shoot tip cultures were tested for determination of onion yellow dwarf virus (OYDV) and leek yellow stripe virus (LYSV) through real-time PCR assay. In garlic plants propagated via meristem culture, we could not detect any virus. OYDV and LYSV viruses were detected in plants obtained via shoot tip culture. OYDV virus was observed in amount of 80% and 73% of tested plants for A. tuncelianum and A. sativum, respectively. LYSV virus was found in amount of 67% of tested plants of A. tuncelianum and in amount of 87% of tested plants of A. sativum in this study.

  17. Use of Tissue Culture Techniques for Producing Virus-Free Plant in Garlic and Their Identification through Real-Time PCR

    PubMed Central

    Taşkın, Hatıra; Baktemur, Gökhan; Kurul, Mehmet; Büyükalaca, Saadet

    2013-01-01

    This study was performed for comparison of meristem culture technique with shoot tip culture technique for obtaining virus-free plant, comparison of micropropagation success of two different nutrient media, and determination of effectiveness of real-time PCR assay for the detection of viruses. Two different garlic species (Allium sativum and Allium tuncelianum) and two different nutrient media were used in this experiment. Results showed that Medium 2 was more successful compared to Medium 1 for both A. tuncelianum and A. sativum (Kastamonu garlic clone). In vitro plants obtained via meristem and shoot tip cultures were tested for determination of onion yellow dwarf virus (OYDV) and leek yellow stripe virus (LYSV) through real-time PCR assay. In garlic plants propagated via meristem culture, we could not detect any virus. OYDV and LYSV viruses were detected in plants obtained via shoot tip culture. OYDV virus was observed in amount of 80% and 73% of tested plants for A. tuncelianum and A. sativum, respectively. LYSV virus was found in amount of 67% of tested plants of A. tuncelianum and in amount of 87% of tested plants of A. sativum in this study. PMID:23935432

  18. Spectroscopic studies of uranium species for environmental decontamination applications

    NASA Astrophysics Data System (ADS)

    Eng, Charlotte

    After the Cold War, Department of Energy began to concentrate its efforts on cleanup of former nuclear material processing facilities, especially uranium-contaminated groundwater and soil. This research aims to study uranium association to both organic and inorganic compounds found in the contaminated environment in the hopes that the information gathered can be applied to the development and optimization of cost-effective remediation techniques. Spectroscopic and electrochemical methods will be employed to examine the behavior of uranium in given conditions to further our understanding of its impact on the environment. Uranium found in groundwater and soil bind with various ligands, especially organic ligands present in the environment due to natural sources (e.g. metabolic by-products or degradation of plants and animals) or man-made sources (e.g. chelating agents used in operating or cleanup of uranium processing facilities). We selected reasonable analogs of naturally occurring matter and studied their structure, chemical and electrochemical behavior and found that the structure of uranyl complexes depends heavily on the nature of the ligand and environmental factors such as pH. Association of uranium-organic complexes with anaerobic bacteria, Clostridium sp. was studied to establish if the bacteria can effectively bioreduce uranium while going through normal bacterial activity. It was found that the nature of the organic ligand affected the bioavailability and toxicity of the uranium on the bacteria. In addition, we have found that the type of iron corrosion products and uranyl species present on the surface of corroded steel depended on various environmental factors, which subsequently affected the removal rate of uranium by a citric acid/hydrogen peroxide/deionized water cleaning process. The method was found to remove uranium from only the topmost corrosion layers and residual uranium could be found (a) deeper in the corrosion layers where it is occluded by

  19. Method of preparation of uranium nitride

    DOEpatents

    Kiplinger, Jaqueline Loetsch; Thomson, Robert Kenneth James

    2013-07-09

    Method for producing terminal uranium nitride complexes comprising providing a suitable starting material comprising uranium; oxidizing the starting material with a suitable oxidant to produce one or more uranium(IV)-azide complexes; and, sufficiently irradiating the uranium(IV)-azide complexes to produce the terminal uranium nitride complexes.

  20. Principal uranium deposits of the world

    USGS Publications Warehouse

    Byers, Virginia P.

    1978-01-01

    The geology of the principal world uranium deposits that have identified uranium reserves and production, as described in published literature, is summarized briefly, including such features as type of deposit, host rock and age of host roc, age of mineralization, depositional environment, and mineralogy. The deposits are located on four maps with the deposit grouped according to age of host rocks?Precambrian, Paleozoic, Mesozoic, and Cenozoic?and further subdivided into types of deposits and size categories. Types of deposits are penecordant sandstone, quartz-pebble conglomerate, vein and vein-type, marine black shale, phosphate deposits, coaly carbonaceous rocks, and pegmatic and alaskitic rocks. The economically most significant deposits of uranium known in 1975 are in quartz-pebble conglomerates and sandstones, which together represented about 75 percent of the world?s total production. The largest deposits occur in quartz-pebble conglomerate at the Elliot Lake-Blind River area, Canada (average grade 0.12 percent U3O8), and at the Witwatersrand basin area in the Republic of South Africa (average grade 0.025 percent U3O8), where uranium is produced principally as a byproduct or coproduct of gold mining; and in medium-grained sandstones in the Colorado Plateau, USA (average grade 0.2 percent U3O8). Other economically significant concentrations are vein, pegmatite or contact metamorphic types, containing smaller but relatively high-grade tonnages and representing about 20 percent of the world?s total production. At Vastergotland (Billingen) and Narke in Sweden, uranium has been recovered on a pilot-plant basis from black shale deposits having an uncommonly high grade for black shale of 0.03 percent U3O8. ?Recoverable reserves? in the near future (40 year period, lifetime of nuclear plants) is on the order of 50,000 metric tons U. Over 50 percent of the world?s total uranium reserves is located on or near the trend of the iron deposits in the Precambrian iron

  1. Profile of World Uranium Enrichment Programs - 2007

    SciTech Connect

    Laughter, Mark D

    2007-11-01

    It is generally agreed that the most difficult step in building a nuclear weapon is acquiring weapons grade fissile material, either plutonium or highly enriched uranium (HEU). Plutonium is produced in a nuclear reactor, while HEU is produced using a uranium enrichment process. Enrichment is also an important step in the civil nuclear fuel cycle, in producing low enriched uranium (LEU) for use in fuel for nuclear reactors. However, the same equipment used to produce LEU for nuclear fuel can also be used to produce HEU for weapons. Safeguards at an enrichment plant are the array of assurances and verification techniques that ensure uranium is only enriched to LEU, no undeclared LEU is produced, and no uranium is enriched to HEU or secretly diverted. There are several techniques for enriching uranium. The two most prevalent are gaseous diffusion, which uses older technology and requires a lot of energy, and gas centrifuge separation, which uses more advanced technology and is more energy efficient. Gaseous diffusion plants (GDPs) provide about 40% of current world enrichment capacity, but are being phased out as newer gas centrifuge enrichment plants (GCEPs) are constructed. Estimates of current and future enrichment capacity are always approximate, due to the constant upgrades, expansions, and shutdowns occurring at enrichment plants, largely determined by economic interests. Currently, the world enrichment capacity is approximately 53 million kg-separative work units (SWU) per year, with 22 million in gaseous diffusion and 31 million in gas centrifuge plants. Another 23 million SWU/year of capacity are under construction or planned for the near future, almost entirely using gas centrifuge separation. Other less-efficient techniques have also been used in the past, including electromagnetic and aerodynamic separations, but these are considered obsolete, at least from a commercial perspective. Laser isotope separation shows promise as a possible enrichment technique

  2. Assessment of nitrous oxide emission from cement plants: real data measured with both Fourier transform infrared and nondispersive infrared techniques.

    PubMed

    Mosca, Silvia; Benedetti, Paolo; Guerriero, Ettore; Rotatori, Mauro

    2014-11-01

    Nitrous oxide (N2O) is the third most important greenhouse gas after carbon dioxide and methane, and contributes about 6% to the greenhouse effect. Nitrous oxide is a minor component of the atmosphere, and it is a thousand times less than carbon dioxide (CO2). Nevertheless, it is much more potent than CO2 and methane, owing to its long stay in the atmosphere of approximately 120 yr and the high global warmingpotential (GWP) of298 times that of CO2. Although greenhouse gases are natural in the atmosphere, human activities have changed the atmospheric concentrations. Most of the values of emission of nitrous oxide are still obtained by means ofemission factors and not actually measured; the lack ofreal data may result in an underestimation ofcurrent emissions. The emission factors used for the calculation of N2O can be obtained from the "Guidelines for the implementation of the national inventory of emissions" of the Intergovernmental Panel on Climate Change, which refer to all nations for the realization of their inventory. This study will present real data, measured in several Italian cement plants with different characteristics. The work also shows a comparison between N2O concentration measured with in situ-Fourier transform IR (FTIR) and the reference method EN ISO 21258 based on nondispersive IR (NDIR), in order to investigate the interfering compounds in the measurement with NDIR.

  3. Method of preparing uranium nitride or uranium carbonitride bodies

    DOEpatents

    Wilhelm, Harley A.; McClusky, James K.

    1976-04-27

    Sintered uranium nitride or uranium carbonitride bodies having a controlled final carbon-to-uranium ratio are prepared, in an essentially continuous process, from U.sub.3 O.sub.8 and carbon by varying the weight ratio of carbon to U.sub.3 O.sub.8 in the feed mixture, which is compressed into a green body and sintered in a continuous heating process under various controlled atmospheric conditions to prepare the sintered bodies.

  4. Final Technical Report - In-line Uranium Immunosensor

    SciTech Connect

    Blake, Diane A.

    2006-07-05

    In this project, personnel at Tulane University and Sapidyne Instruments Inc. developed an in-line uranium immunosensor that could be used to determine the efficacy of specific in situ biostimulation approaches. This sensor was designed to operate autonomously over relatively long periods of time (2-10 days) and was able to provide near real-time data about uranium immobilization in the absence of personnel at the site of the biostimulation experiments. An alpha prototype of the in-line immmunosensor was delivered from Sapidyne Instruments to Tulane University in December of 2002 and a beta prototype was delivered in November of 2003. The beta prototype of this instrument (now available commercially from Sapidyne Instruments) was programmed to autonomously dilute standard uranium to final concentrations of 2.5 to 100 nM (0.6 to 24 ppb) in buffer containing a fluorescently labeled anti-uranium antibody and the uranium chelator, 2,9-dicarboxyl-1,10-phenanthroline. The assay limit of detection for hexavalent uranium was 5.8 nM or 1.38 ppb. This limit of detection is well below the drinking water standard of 30 ppb recently promulgated by the EPA. The assay showed excellent precision; the coefficients of variation (CV’s) in the linear range of the assay were less than 5% and CV’s never rose above 14%. Analytical recovery in the immunosensors-based assay was assessed by adding variable known quantities of uranium to purified water samples. A quantitative recovery (93.75% - 108.17%) was obtained for sample with concentrations from 7.5 to 20 nM (2-4.75 ppb). In August of 2005 the sensor was transported to Oak Ridge National Laboratory, for testing of water samples at the Criddle test site (see Wu et al., Environ. Sci. Technol. 40:3978-3985 2006 for a description of this site). In this first on-site test, the in-line sensor was able to accurately detect changes in the concentrations of uranium in effluent samples from this site. Although the absolute values for the

  5. Method for fabricating uranium foils and uranium alloy foils

    DOEpatents

    Hofman, Gerard L.; Meyer, Mitchell K.; Knighton, Gaven C.; Clark, Curtis R.

    2006-09-05

    A method of producing thin foils of uranium or an alloy. The uranium or alloy is cast as a plate or sheet having a thickness less than about 5 mm and thereafter cold rolled in one or more passes at substantially ambient temperatures until the uranium or alloy thereof is in the shape of a foil having a thickness less than about 1.0 mm. The uranium alloy includes one or more of Zr, Nb, Mo, Cr, Fe, Si, Ni, Cu or Al.

  6. RECOVERY OF URANIUM FROM ZIRCONIUM-URANIUM NUCLEAR FUELS

    DOEpatents

    Gens, T.A.

    1962-07-10

    An improvement was made in a process of recovering uranium from a uranium-zirconium composition which was hydrochlorinated with gsseous hydrogen chloride at a temperature of from 350 to 800 deg C resulting in volatilization of the zirconium, as zirconium tetrachloride, and the formation of a uranium containing nitric acid insoluble residue. The improvement consists of reacting the nitric acid insoluble hydrochlorination residue with gaseous carbon tetrachloride at a temperature in the range 550 to 600 deg C, and thereafter recovering the resulting uranium chloride vapors. (AEC)

  7. PROCESS FOR PRODUCING URANIUM TETRAFLUORIDE

    DOEpatents

    Harvey, B.G.

    1954-09-14

    >This patent relates to improvements in the method for producing uranium tetrafluoride by treating an aqueous solutlon of a uranyl salt at an elevated temperature with a reducing agent effective in acld solutlon in the presence of hydrofluoric acid. Uranium tetrafluoride produced this way frequentiy contains impurities in the raw material serving as the source of uranium. Uranium tetrafluoride much less contaminated with impurities than when prepared by the above method can be prepared from materials containing such impurities by first adding a small proportion of reducing agent so as to cause a small fraction, for example 1 to 5% of the uranium tetrafluoride to be precipitated, rejecting such precipitate, and then precipitating and recovering the remainder of the uranium tetrafluoride.

  8. ELECTROLYSIS OF THORIUM AND URANIUM

    DOEpatents

    Hansen, W.N.

    1960-09-01

    An electrolytic method is given for obtaining pure thorium, uranium, and thorium-uranium alloys. The electrolytic cell comprises a cathode composed of a metal selected from the class consisting of zinc, cadmium, tin, lead, antimony, and bismuth, an anode composed of at least one of the metals selected from the group consisting of thorium and uranium in an impure state, and an electrolyte composed of a fused salt containing at least one of the salts of the metals selected from the class consisting of thorium, uranium. zinc, cadmium, tin, lead, antimony, and bismuth. Electrolysis of the fused salt while the cathode is maintained in the molten condition deposits thorium, uranium, or thorium-uranium alloys in pure form in the molten cathode which thereafter may be separated from the molten cathode product by distillation.

  9. Elution of Uranium and Transition Metals from Amidoxime-Based Polymer Adsorbents for Sequestering Uranium from Seawater

    SciTech Connect

    Pan, Horng-Bin; Kuo, Li-Jung; Wai, Chien M.; Miyamoto, Naomi; Joshi, Ruma; Wood, Jordana R.; Strivens, Jonathan E.; Janke, Christopher J.; Oyola, Yatsandra; Das, Sadananda; Mayes, Richard T.; Gill, Gary A.

    2015-11-30

    High-surface-area amidoxime and carboxylic acid grafted polymer adsorbents developed at Oak Ridge National Laboratory were tested for sequestering uranium in a flowing seawater flume system at the PNNL-Marine Sciences Laboratory. FTIR spectra indicate that a KOH conditioning process is necessary to remove the proton from the carboxylic acid and make the sorbent effective for sequestering uranium from seawater. The alkaline conditioning process also converts the amidoxime groups to carboxylate groups in the adsorbent. Both Na2CO3-H2O2 and hydrochloric acid elution methods can remove ~95% of the uranium sequestered by the adsorbent after 42 days of exposure in real seawater. The Na2CO3-H2O2 elution method is more selective for uranium than conventional acid elution. Iron and vanadium are the two major transition metals competing with uranium for adsorption to the amidoxime-based adsorbents in real seawater.

  10. Elution of uranium and transition metals from amidoxime-based polymer adsorbents for sequestering uranium from seawater

    DOE PAGES

    Pan, Horng-Bin; Kuo, Li-Jung; Miyamoto, Naomi; ...

    2015-11-30

    High-surface-area amidoxime and carboxylic acid grafted polymer adsorbents developed at Oak Ridge National Laboratory were tested for sequestering uranium in a flowing seawater flume system at the PNNL-Marine Sciences Laboratory. FTIR spectra indicate that a KOH conditioning process is necessary to remove the proton from the carboxylic acid and make the sorbent effective for sequestering uranium from seawater. The alkaline conditioning process also converts the amidoxime groups to carboxylate groups in the adsorbent. Both Na2CO3 H2O2 and hydrochloric acid elution methods can remove ~95% of the uranium sequestered by the adsorbent after 42 days of exposure in real seawater. Themore » Na2CO3 H2O2 elution method is more selective for uranium than conventional acid elution. Iron and vanadium are the two major transition metals competing with uranium for adsorption to the amidoxime-based adsorbents in real seawater. Tiron (4,5-Dihydroxy-1,3-benzenedisulfonic acid disodium salt, 1 M) can remove iron from the adsorbent very effectively at pH around 7. The coordination between vanadium (V) and amidoxime is also discussed based on our 51V NMR data.« less

  11. Elution of uranium and transition metals from amidoxime-based polymer adsorbents for sequestering uranium from seawater

    SciTech Connect

    Pan, Horng-Bin; Kuo, Li-Jung; Miyamoto, Naomi; Wood, Jordana; Strivens, Jonathan E.; Gill, Gary; Janke, Christopher James; Wai, Chien

    2015-11-30

    High-surface-area amidoxime and carboxylic acid grafted polymer adsorbents developed at Oak Ridge National Laboratory were tested for sequestering uranium in a flowing seawater flume system at the PNNL-Marine Sciences Laboratory. FTIR spectra indicate that a KOH conditioning process is necessary to remove the proton from the carboxylic acid and make the sorbent effective for sequestering uranium from seawater. The alkaline conditioning process also converts the amidoxime groups to carboxylate groups in the adsorbent. Both Na2CO3 H2O2 and hydrochloric acid elution methods can remove ~95% of the uranium sequestered by the adsorbent after 42 days of exposure in real seawater. The Na2CO3 H2O2 elution method is more selective for uranium than conventional acid elution. Iron and vanadium are the two major transition metals competing with uranium for adsorption to the amidoxime-based adsorbents in real seawater. Tiron (4,5-Dihydroxy-1,3-benzenedisulfonic acid disodium salt, 1 M) can remove iron from the adsorbent very effectively at pH around 7. The coordination between vanadium (V) and amidoxime is also discussed based on our 51V NMR data.

  12. Uranium Mines and Mills Location Database

    EPA Pesticide Factsheets

    The Uranium Mines and Mills location database identifies and shows the location of active and inactive uranium mines and mills, as well as mines which principally produced other minerals, but were known to have uranium in the ore.

  13. PROCESS FOR REMOVING NOBLE METALS FROM URANIUM

    DOEpatents

    Knighton, J.B.

    1961-01-31

    A pyrometallurgical method is given for purifying uranium containing ruthenium and palladium. The uranium is disintegrated and oxidized by exposure to air and then the ruthenium and palladium are extracted from the uranium with molten zinc.

  14. The chemistry of the uranium oxyfluorides

    SciTech Connect

    Manuta, D.M.

    1995-12-31

    Uranuim oxyfluorides result from the hydrolysis of uranium hexafluoride. The ratio of water to uranium hexafluoride determines the uranium oxyfluoride product formed. Uranyl fluoride is the most important of the compounds formed.

  15. FORMATION OF URANIUM PRECIPITATES

    DOEpatents

    Googin, J.M. Jr.

    1959-03-17

    A method is described for precipitation of uranium peroxide from uranium- containing solutions so as to obtain larger aggregates which facilitates washings decantations filtrations centrifugations and the like. The desired larger aggregate form is obtained by maintaining the pH of the solution in the approximate range of 1 to 3 and the temperature at about 25 deg C or below while carrytng out the precipitation. Then prior to removal of the precipitate a surface active sulfonated bicarboxyacids such as di-octyl sodium sulfo-succinates is incorporated in an anount of the order of 0.01 to 0.05 percent by weights and the slurry is allowed to ripen for about one-half hour at a temperatare below 10 deg C.

  16. METHOD OF PRODUCING URANIUM

    DOEpatents

    Foster, L.S.; Magel, T.T.

    1958-05-13

    A modified process is described for the production of uranium metal by means of a bomb reduction of UF/sub 4/. Difficulty is sometimes experienced in obtaining complete separation of the uranium from the slag when the process is carried out on a snnall scale, i.e., for the production of 10 grams of U or less. Complete separation may be obtained by incorporating in the reaction mixture a quantity of MnCl/sub 2/, so that this compound is reduced along with the UF/sub 4/ . As a result a U--Mn alloy is formed which has a melting point lower than that of pure U, and consequently the metal remains molten for a longer period allowing more complete separation from the slag.

  17. Instabilities in uranium plasma.

    NASA Technical Reports Server (NTRS)

    Tidman, D. A.

    1971-01-01

    The nonlinear evolution of unstable sound waves in a uranium plasma has been calculated using a multiple time-scale asymptotic expansion scheme. The fluid equations used include the fission power density, radiation diffusion, and the effects of the changing degree of ionization of the uranium atoms. The nonlinear growth of unstable waves is shown to be limited by mode coupling to shorter wavelength waves which are damped by radiation diffusion. This mechanism limits the wave pressure fluctuations to values of order delta P/P equal to about .00001 in the plasma of a typical gas-core nuclear rocket engine. The instability is thus not expected to present a control problem for this engine.

  18. Instabilities in uranium plasma.

    NASA Technical Reports Server (NTRS)

    Tidman, D. A.

    1971-01-01

    The nonlinear evolution of unstable sound waves in a uranium plasma has been calculated using a multiple time-scale asymptotic expansion scheme. The fluid equations used include the fission power density, radiation diffusion, and the effects of the changing degree of ionization of the uranium atoms. The nonlinear growth of unstable waves is shown to be limited by mode coupling to shorter wavelength waves which are damped by radiation diffusion. This mechanism limits the wave pressure fluctuations to values of order delta P/P equal to about .00001 in the plasma of a typical gas-core nuclear rocket engine. The instability is thus not expected to present a control problem for this engine.

  19. A Real-Time Data Acquisition and Processing Framework Based on FlexRIO FPGA and ITER Fast Plant System Controller

    NASA Astrophysics Data System (ADS)

    Yang, C.; Zheng, W.; Zhang, M.; Yuan, T.; Zhuang, G.; Pan, Y.

    2016-06-01

    Measurement and control of the plasma in real-time are critical for advanced Tokamak operation. It requires high speed real-time data acquisition and processing. ITER has designed the Fast Plant System Controllers (FPSC) for these purposes. At J-TEXT Tokamak, a real-time data acquisition and processing framework has been designed and implemented using standard ITER FPSC technologies. The main hardware components of this framework are an Industrial Personal Computer (IPC) with a real-time system and FlexRIO devices based on FPGA. With FlexRIO devices, data can be processed by FPGA in real-time before they are passed to the CPU. The software elements are based on a real-time framework which runs under Red Hat Enterprise Linux MRG-R and uses Experimental Physics and Industrial Control System (EPICS) for monitoring and configuring. That makes the framework accord with ITER FPSC standard technology. With this framework, any kind of data acquisition and processing FlexRIO FPGA program can be configured with a FPSC. An application using the framework has been implemented for the polarimeter-interferometer diagnostic system on J-TEXT. The application is able to extract phase-shift information from the intermediate frequency signal produced by the polarimeter-interferometer diagnostic system and calculate plasma density profile in real-time. Different algorithms implementations on the FlexRIO FPGA are compared in the paper.

  20. METHOD OF JACKETING URANIUM BODIES

    DOEpatents

    Maloney, J.O.; Haines, E.B.; Tepe, J.B.

    1958-08-26

    An improved process is presented for providing uranium slugs with thin walled aluminum jackets. Since aluminum has a slightiy higher coefficient of thermal expansion than does uraaium, both uranium slugs and aluminum cans are heated to an elevated temperature of about 180 C, and the slug are inserted in the cans at that temperature. During the subsequent cooling of the assembly, the aluminum contracts more than does the uranium and a tight shrink fit is thus assured.

  1. PROCESS FOR PREPARING URANIUM METAL

    DOEpatents

    Prescott, C.H. Jr.; Reynolds, F.L.

    1959-01-13

    A process is presented for producing oxygen-free uranium metal comprising contacting iodine vapor with crude uranium in a reaction zone maintained at 400 to 800 C to produce a vaporous mixture of UI/sub 4/ and iodine. Also disposed within the maction zone is a tungsten filament which is heated to about 1600 C. The UI/sub 4/, upon contacting the hot filament, is decomposed to molten uranium substantially free of oxygen.

  2. METHOD OF DISSOLVING URANIUM METAL

    DOEpatents

    Slotin, L.A.

    1958-02-18

    This patent relates to an economicai means of dissolving metallic uranium. It has been found that the addition of a small amount of perchloric acid to the concentrated nitric acid in which the uranium is being dissolved greatly shortens the time necessary for dissolution of the metal. Thus the use of about 1 or 2 percent of perchioric acid based on the weight of the nitric acid used, reduces the time of dissolution of uranium by a factor of about 100.

  3. WELDED JACKETED URANIUM BODY

    DOEpatents

    Gurinsky, D.H.

    1958-08-26

    A fuel element is presented for a neutronic reactor and is comprised of a uranium body, a non-fissionable jacket surrounding sald body, thu jacket including a portion sealed by a weld, and an inclusion in said sealed jacket at said weld of a fiux having a low neutron capture cross-section. The flux is provided by combining chlorine gas and hydrogen in the intense heat of-the arc, in a "Heliarc" welding muthod, to form dry hydrochloric acid gas.

  4. Uranium price forecasting methods

    SciTech Connect

    Fuller, D.M.

    1994-03-01

    This article reviews a number of forecasting methods that have been applied to uranium prices and compares their relative strengths and weaknesses. The methods reviewed are: (1) judgemental methods, (2) technical analysis, (3) time-series methods, (4) fundamental analysis, and (5) econometric methods. Historically, none of these methods has performed very well, but a well-thought-out model is still useful as a basis from which to adjust to new circumstances and try again.

  5. An analysis of the impact of having uranium dioxide mixed in with plutonium dioxide

    SciTech Connect

    MARUSICH, R.M.

    1998-10-21

    An assessment was performed to show the impact on airborne release fraction, respirable fraction, dose conversion factor and dose consequences of postulated accidents at the Plutonium Finishing Plant involving uranium dioxide rather than plutonium dioxide.

  6. METHOD FOR RECOVERING URANIUM FROM OILS

    DOEpatents

    Gooch, L.H.

    1959-07-14

    A method is presented for recovering uranium from hydrocarbon oils, wherein the uranium is principally present as UF/sub 4/. According to the invention, substantially complete removal of the uranium from the hydrocarbon oil may be effected by intimately mixing one part of acetone to about 2 to 12 parts of the hydrocarbon oil containing uranium and separating the resulting cake of uranium from the resulting mixture. The uranium in the cake may be readily recovered by burning to the oxide.

  7. Depleted Uranium in Repositories

    SciTech Connect

    Haire, M.J.; Croff, A.G.

    1997-12-31

    For uranium to be useful in most fission nuclear reactors, it must be enriched (i.e. the concentration of the fissile isotope 235U must be increased). Therefore, depleted uranium (DU)-uranium which has less than naturally occurring concentrations of 235U-is a co-product of the enrichment process. Four to six tons of DU exist for every ton of fresh light water reactor fuel. There were 407,006 MgU 407,000 metric tons (t) of DU stored on U.S. Department of Energy (DOE) sites as of July 1993. If this DU were to be declared surplus, converted to a stable oxide form, and emplaced in a near surface disposal facility, the costs are estimated to be several billion dollars. However, the U.S. Nuclear Regulatory Commission has stated that near surface disposal of large quantities of DU tails is not appropriate. Thus, there is the possibility that disposition via disposal will be in a deep geological repository. One alternative that may significantly reduce the cost of DU disposition is to use it beneficially. In fact, DOE has begun the Beneficial Uses of DU Project to identify large scale uses of DU and to encourage its reuse. Several beneficial uses, many of which involve applications in the repository per se or in managing the wastes to go into the repository, are discussed in this report.

  8. Sputtering of uranium

    NASA Technical Reports Server (NTRS)

    Gregg, R.; Tombrello, T. A.

    1978-01-01

    Results are presented for an experimental study of the sputtering of U-235 atoms from foil targets by hydrogen, helium, and argon ions, which was performed by observing tracks produced in mica by fission fragments following thermal-neutron-induced fission. The technique used allowed measurements of uranium sputtering yields of less than 0.0001 atom/ion as well as yields involving the removal of less than 0.01 monolayer of the uranium target surface. The results reported include measurements of the sputtering yields for 40-120-keV protons, 40-120-keV He-4(+) ions, and 40- and 80-keV Ar-40(+) ions, the mass distribution of chunks emitted during sputtering by the protons and 80-keV Ar-40(+) ions, the total chunk yield during He-4(+) sputtering, and some limited data on molecular sputtering by H2(+) and H3(+). The angular distribution of the sputtered uranium is discussed, and the yields obtained are compared with the predictions of collision cascade theory.

  9. The Toxicity of Depleted Uranium

    PubMed Central

    Briner, Wayne

    2010-01-01

    Depleted uranium (DU) is an emerging environmental pollutant that is introduced into the environment primarily by military activity. While depleted uranium is less radioactive than natural uranium, it still retains all the chemical toxicity associated with the original element. In large doses the kidney is the target organ for the acute chemical toxicity of this metal, producing potentially lethal tubular necrosis. In contrast, chronic low dose exposure to depleted uranium may not produce a clear and defined set of symptoms. Chronic low-dose, or subacute, exposure to depleted uranium alters the appearance of milestones in developing organisms. Adult animals that were exposed to depleted uranium during development display persistent alterations in behavior, even after cessation of depleted uranium exposure. Adult animals exposed to depleted uranium demonstrate altered behaviors and a variety of alterations to brain chemistry. Despite its reduced level of radioactivity evidence continues to accumulate that depleted uranium, if ingested, may pose a radiologic hazard. The current state of knowledge concerning DU is discussed. PMID:20195447

  10. ELECTROLYTIC PRODUCTION OF URANIUM TETRAFLUORIDE

    DOEpatents

    Lofthouse, E.

    1954-08-31

    This patent relates to electrolytic methods for the production of uranium tetrafluoride. According to the present invention a process for the production of uranium tetrafluoride comprises submitting to electrolysis an aqueous solution of uranyl fluoride containing free hydrofluoric acid. Advantageously the aqueous solution of uranyl fluoride is obtained by dissolving uranium hexafluoride in water. On electrolysis, the uranyl ions are reduced to uranous tons at the cathode and immediately combine with the fluoride ions in solution to form the insoluble uranium tetrafluoride which is precipitated.

  11. THERMAL DECOMPOSITION OF URANIUM COMPOUNDS

    DOEpatents

    Magel, T.T.; Brewer, L.

    1959-02-10

    A method is presented of preparing uranium metal of high purity consisting contacting impure U metal with halogen vapor at between 450 and 550 C to form uranium halide vapor, contacting the uranium halide vapor in the presence of H/sub 2/ with a refractory surface at about 1400 C to thermally decompose the uranium halides and deposit molten U on the refractory surface and collecting the molten U dripping from the surface. The entire operation is carried on at a sub-atmospheric pressure of below 1 mm mercury.

  12. Uranium droplet core nuclear rocket

    NASA Technical Reports Server (NTRS)

    Anghaie, Samim

    1991-01-01

    Uranium droplet nuclear rocket is conceptually designed to utilize the broad temperature range ofthe liquid phase of metallic uranium in droplet configuration which maximizes the energy transfer area per unit fuel volume. In a baseline system dissociated hydrogen at 100 bar is heated to 6000 K, providing 2000 second of Isp. Fission fragments and intense radian field enhance the dissociation of molecular hydrogen beyond the equilibrium thermodynamic level. Uranium droplets in the core are confined and separated by an axisymmetric vortex flow generated by high velocity tangential injection of hydrogen in the mid-core regions. Droplet uranium flow to the core is controlled and adjusted by a twin flow nozzle injection system.

  13. Uranium droplet core nuclear rocket

    NASA Technical Reports Server (NTRS)

    Anghaie, Samim

    1991-01-01

    Uranium droplet nuclear rocket is conceptually designed to utilize the broad temperature range ofthe liquid phase of metallic uranium in droplet configuration which maximizes the energy transfer area per unit fuel volume. In a baseline system dissociated hydrogen at 100 bar is heated to 6000 K, providing 2000 second of Isp. Fission fragments and intense radian field enhance the dissociation of molecular hydrogen beyond the equilibrium thermodynamic level. Uranium droplets in the core are confined and separated by an axisymmetric vortex flow generated by high velocity tangential injection of hydrogen in the mid-core regions. Droplet uranium flow to the core is controlled and adjusted by a twin flow nozzle injection system.

  14. SEPARATION OF THORIUM FROM URANIUM

    DOEpatents

    Bane, R.W.

    1959-09-01

    A description is given for the separation of thorium from uranium by forming an aqueous acidic solution containing ionic species of thorium, uranyl uranium, and hydroxylamine, flowing the solution through a column containing the phenol-formaldehyde type cation exchange resin to selectively adsorb substantially all the thorium values and a portion of the uranium values, flowing a dilute solution of hydrochloric acid through the column to desorb the uranium values, and then flowing a dilute aqueous acidic solution containing an ion, such as bisulfate, which has a complexing effect upon thortum through the column to desorb substantially all of the thorium.

  15. Potential uranium supply from phosphoric acid: A U.S. analysis comparing solvent extraction and Ion exchange recovery

    DOE PAGES

    Kim, Haeyeon; G. Eggert, Roderick; W. Carlsen, Brett; ...

    2016-06-16

    Phosphate rock contains significant amounts of uranium, although in low concentrations. Recovery of uranium as a by-product from phosphoric acid, an intermediate product produced during the recovery of phosphorus from phosphate rock, is not unprecedented. Phosphoric acid plants ceased to produce uranium as a by-product in the early 1990s with the fall of uranium prices. In the last decade, this topic has regained attention due to higher uranium prices and expected increase in demand for uranium. Our study revisits the topic and estimates how much uranium might be recoverable from current phosphoric acid production in the United States and whatmore » the associated costs might be considering two different recovery processes: solvent extraction and ion exchange. Based on U.S. phosphoric acid production in 2014, 5.5 million pounds of U3O8 could have been recovered, more than domestic U.S. mine production of uranium in the same year. Annualized costs for a hypothetical uranium recovery plant are US$48-66 per pound U3O8 for solvent extraction, the process used historically in the United States to recover uranium from phosphoric acid. For ion exchange, not yet proven at a commercial scale for uranium recovery, the estimated costs are US$33-54 per pound U3O8. Our results suggest that it is technically possible for the United States to recover significant quantities of uranium from current phosphoric acid production. And for this type of uranium production to be economically attractive on a large scale, either recovery costs must fall or uranium prices rise.« less

  16. Potential uranium supply from phosphoric acid: A U.S. analysis comparing solvent extraction and Ion exchange recovery

    SciTech Connect

    Kim, Haeyeon; G. Eggert, Roderick; W. Carlsen, Brett; W. Dixon, Brent

    2016-06-16

    Phosphate rock contains significant amounts of uranium, although in low concentrations. Recovery of uranium as a by-product from phosphoric acid, an intermediate product produced during the recovery of phosphorus from phosphate rock, is not unprecedented. Phosphoric acid plants ceased to produce uranium as a by-product in the early 1990s with the fall of uranium prices. In the last decade, this topic has regained attention due to higher uranium prices and expected increase in demand for uranium. Our study revisits the topic and estimates how much uranium might be recoverable from current phosphoric acid production in the United States and what the associated costs might be considering two different recovery processes: solvent extraction and ion exchange. Based on U.S. phosphoric acid production in 2014, 5.5 million pounds of U3O8 could have been recovered, more than domestic U.S. mine production of uranium in the same year. Annualized costs for a hypothetical uranium recovery plant are US$48-66 per pound U3O8 for solvent extraction, the process used historically in the United States to recover uranium from phosphoric acid. For ion exchange, not yet proven at a commercial scale for uranium recovery, the estimated costs are US$33-54 per pound U3O8. Our results suggest that it is technically possible for the United States to recover significant quantities of uranium from current phosphoric acid production. And for this type of uranium production to be economically attractive on a large scale, either recovery costs must fall or uranium prices rise.

  17. Factors influencing real time internal structural visualization and dynamic process monitoring in plants using synchrotron-based phase contrast X-ray imaging.

    PubMed

    Karunakaran, Chithra; Lahlali, Rachid; Zhu, Ning; Webb, Adam M; Schmidt, Marina; Fransishyn, Kyle; Belev, George; Wysokinski, Tomasz; Olson, Jeremy; Cooper, David M L; Hallin, Emil

    2015-07-17

    Minimally invasive investigation of plant parts (root, stem, leaves, and flower) has good potential to elucidate the dynamics of plant growth, morphology, physiology, and root-rhizosphere interactions. Laboratory based absorption X-ray imaging and computed tomography (CT) systems are extensively used for in situ feasibility studies of plants grown in natural and artificial soil. These techniques have challenges such as low contrast between soil pore space and roots, long X-ray imaging time, and low spatial resolution. In this study, the use of synchrotron (SR) based phase contrast X-ray imaging (PCI) has been demonstrated as a minimally invasive technique for imaging plants. Above ground plant parts and roots of 10 day old canola and wheat seedlings grown in sandy clay loam soil were successfully scanned and reconstructed. Results confirmed that SR-PCI can deliver good quality images to study dynamic and real time processes such as cavitation and water-refilling in plants. The advantages of SR-PCI, effect of X-ray energy, and effective pixel size to study plant samples have been demonstrated. The use of contrast agents to monitor physiological processes in plants was also investigated and discussed.

  18. Factors influencing real time internal structural visualization and dynamic process monitoring in plants using synchrotron-based phase contrast X-ray imaging

    NASA Astrophysics Data System (ADS)

    Karunakaran, Chithra; Lahlali, Rachid; Zhu, Ning; Webb, Adam M.; Schmidt, Marina; Fransishyn, Kyle; Belev, George; Wysokinski, Tomasz; Olson, Jeremy; Cooper, David M. L.; Hallin, Emil

    2015-07-01

    Minimally invasive investigation of plant parts (root, stem, leaves, and flower) has good potential to elucidate the dynamics of plant growth, morphology, physiology, and root-rhizosphere interactions. Laboratory based absorption X-ray imaging and computed tomography (CT) systems are extensively used for in situ feasibility studies of plants grown in natural and artificial soil. These techniques have challenges such as low contrast between soil pore space and roots, long X-ray imaging time, and low spatial resolution. In this study, the use of synchrotron (SR) based phase contrast X-ray imaging (PCI) has been demonstrated as a minimally invasive technique for imaging plants. Above ground plant parts and roots of 10 day old canola and wheat seedlings grown in sandy clay loam soil were successfully scanned and reconstructed. Results confirmed that SR-PCI can deliver good quality images to study dynamic and real time processes such as cavitation and water-refilling in plants. The advantages of SR-PCI, effect of X-ray energy, and effective pixel size to study plant samples have been demonstrated. The use of contrast agents to monitor physiological processes in plants was also investigated and discussed.

  19. Factors influencing real time internal structural visualization and dynamic process monitoring in plants using synchrotron-based phase contrast X-ray imaging

    PubMed Central

    Karunakaran, Chithra; Lahlali, Rachid; Zhu, Ning; Webb, Adam M.; Schmidt, Marina; Fransishyn, Kyle; Belev, George; Wysokinski, Tomasz; Olson, Jeremy; Cooper, David M. L.; Hallin, Emil

    2015-01-01

    Minimally invasive investigation of plant parts (root, stem, leaves, and flower) has good potential to elucidate the dynamics of plant growth, morphology, physiology, and root-rhizosphere interactions. Laboratory based absorption X-ray imaging and computed tomography (CT) systems are extensively used for in situ feasibility studies of plants grown in natural and artificial soil. These techniques have challenges such as low contrast between soil pore space and roots, long X-ray imaging time, and low spatial resolution. In this study, the use of synchrotron (SR) based phase contrast X-ray imaging (PCI) has been demonstrated as a minimally invasive technique for imaging plants. Above ground plant parts and roots of 10 day old canola and wheat seedlings grown in sandy clay loam soil were successfully scanned and reconstructed. Results confirmed that SR-PCI can deliver good quality images to study dynamic and real time processes such as cavitation and water-refilling in plants. The advantages of SR-PCI, effect of X-ray energy, and effective pixel size to study plant samples have been demonstrated. The use of contrast agents to monitor physiological processes in plants was also investigated and discussed. PMID:26183486

  20. Development of a system for real-time measurements of metabolite transport in plants using short-lived positron-emitting radiotracers

    NASA Astrophysics Data System (ADS)

    Kiser, Matthew R.

    Over the past 200 years, the Earth's atmospheric carbon dioxide (CO 2) concentration has increased by more than 35%, and climate experts predict that CO2 levels may double by the end of this century. Understanding the mechanisms of resource management in plants is fundamental for predicting how plants will respond to the increase in atmospheric CO 2. Plant productivity sustains life on Earth and is a principal component of the planet's system that regulates atmospheric CO2 concentration. As such, one of the central goals of plant science is to understand the regulatory mechanisms of plant growth in a changing environment. Short-lived positron-emitting radiotracer techniques provide time-dependent data that are critical for developing models of metabolite transport and resource distribution in plants and their microenvironments. To better understand the effects of environmental changes on resource transport and allocation in plants, we have developed a system for real-time measurements of rnetabolite transport in plants using short-lived positron-emitting radio-tracers. This thesis project includes the design, construction, and demonstration of the capabilities of this system for performing real-time measurements of metabolite transport in plants. The short-lived radiotracer system described in this dissertation takes advantage of the combined capabilities and close proximity of two research facilities at. Duke University: the Triangle Universities Nuclear Laboratory (TUNL) and the Duke University Phytotron, which are separated by approximately 100 meters. The short-lived positron-emitting radioisotopes are generated using the 10-MV tandem Van de Graaff accelerator located in the main TUNL building, which provides the capability of producing short-lived positron-emitting isotopes such as carbon-11 (11C: 20 minute half-life), nitrogen-13 (13N; 10 minute half-life), fluorine-18 (18F; 110 minute half-life), and oxygen-15 (15O; 2 minute half-life). The radioisotopes may

  1. PROCESS OF PRODUCING REFRACTORY URANIUM OXIDE ARTICLES

    DOEpatents

    Hamilton, N.E.

    1957-12-01

    A method is presented for fabricating uranium oxide into a shaped refractory article by introducing a uranium halide fluxing reagent into the uranium oxide, and then mixing and compressing the materials into a shaped composite mass. The shaped mass of uranium oxide and uranium halide is then fired at an elevated temperature so as to form a refractory sintered article. It was found in the present invention that the introduction of a uraninm halide fluxing agent afforded a fluxing action with the uranium oxide particles and that excellent cohesion between these oxide particles was obtained. Approximately 90% of uranium dioxide and 10% of uranium tetrafluoride represent a preferred composition.

  2. Real-time PCR protocols for the quantification of the begomovirus tomato yellow leaf curl Sardinia virus in tomato plants and in its insect vector.

    PubMed

    Noris, Emanuela; Miozzi, Laura

    2015-01-01

    Tomato yellow leaf curl Sardinia virus (TYLCSV) (Geminiviridae) is an important pathogen, transmitted by the whitefly Bemisia tabaci, that severely affects the tomato production in the Mediterranean basin. Here, we describe real-time PCR protocols suitable for relative and absolute quantification of TYLCSV in tomato plants and in whitefly extracts. Using primers and probe specifically designed for TYLCSV, the protocols for relative quantification allow to compare the amount of TYLCSV present in different plant or whitefly samples, normalized to the amount of DNA present in each sample using endogenous tomato or Bemisia genes as internal references. The absolute quantification protocol allows to calculate the number of genomic units of TYLCSV over the genomic units of the plant host (tomato), with a sensitivity of as few as ten viral genome copies per sample. The described protocols are potentially suitable for several applications, such as plant breeding for resistance, analysis of virus replication, and virus-vector interaction studies.

  3. Isotopic signature and nano-texture of cesium-rich micro-particles: Release of uranium and fission products from the Fukushima Daiichi Nuclear Power Plant.

    PubMed

    Imoto, Junpei; Ochiai, Asumi; Furuki, Genki; Suetake, Mizuki; Ikehara, Ryohei; Horie, Kenji; Takehara, Mami; Yamasaki, Shinya; Nanba, Kenji; Ohnuki, Toshihiko; Law, Gareth T W; Grambow, Bernd; Ewing, Rodney C; Utsunomiya, Satoshi

    2017-07-14

    Highly radioactive cesium-rich microparticles (CsMPs) released from the Fukushima Daiichi Nuclear Power Plant (FDNPP) provide nano-scale chemical fingerprints of the 2011 tragedy. U, Cs, Ba, Rb, K, and Ca isotopic ratios were determined on three CsMPs (3.79-780 Bq) collected within ~10 km from the FDNPP to determine the CsMPs' origin and mechanism of formation. Apart from crystalline Fe-pollucite, CsFeSi2O6 · nH2O, CsMPs are comprised mainly of Zn-Fe-oxide nanoparticles in a SiO2 glass matrix (up to ~30 wt% of Cs and ~1 wt% of U mainly associated with Zn-Fe-oxide). The (235)U/(238)U values in two CsMPs: 0.030 (±0.005) and 0.029 (±0.003), are consistent with that of enriched nuclear fuel. The values are higher than the average burnup estimated by the ORIGEN code and lower than non-irradiated fuel, suggesting non-uniform volatilization of U from melted fuels with different levels of burnup, followed by sorption onto Zn-Fe-oxides. The nano-scale texture and isotopic analyses provide a partial record of the chemical reactions that occurred in the fuel during meltdown. Also, the CsMPs were an important medium of transport for the released radionuclides in a respirable form.

  4. Exploration for uranium deposits, Grants mineral belt

    SciTech Connect

    Fitch, D.C.

    1980-01-01

    Uranium ore deposits in the Grants mineral belt, New Mexico, occur in fluvial sandstones in the Morrison Formation (Jurassic). Uranium mineralization is concentrated by a dark-gray to black substance that has been identified as humate, which is derived from decaying vegetation. Black ore is truncated by overlying sandstone in at least three ore deposits, documenting an early age for mineralization. Ore deposits in the Grants mineral belt vary greatly in size and shape, tend to occur in clusters, and often present difficult drill targets. Current exploration is largely a matter of drilling in stages to distinguish favorable from unfavorable ground on a wide spacing, to seek mineralization in favorable ground, and to conduct close-spaced drilling in mineralized areas. Criteria for favorability differ among exploration groups but generally include 1) presence of a host sandstone, 2) anomalous mineralization, 3) color of the host rock, 4) presence of carbonaceous matter, and 5) position of the area relative to mineralized trends. A description of the drilling sequence, from ore discovery to the development of a mine at the Johnny M deposit (in the east part of the Ambrosia Lake district), exemplifies the problem of predicting where orebodies may occur. A study of the drill data at the Johnny M indicates the uranium ore is not related to specific geologic features other than humate, which is commonly associated with coalified plant fragments in mudstone-rich parts of the host sandstone.

  5. 11. VIEW OF DEPLETED URANIUM INGOT. THE METALS WERE PLACED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. VIEW OF DEPLETED URANIUM INGOT. THE METALS WERE PLACED IN CRUCIBLES, LOADED INTO ONE OF EIGHT INDUCTION FURNACES AND MELTED IN A VACUUM ATMOSPHERE. (11/11/57) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  6. 9. VIEW OF FOUNDRY FURNACE, DEPLETED URANIUM INGOTS, BERYLLIUM INGOTS, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. VIEW OF FOUNDRY FURNACE, DEPLETED URANIUM INGOTS, BERYLLIUM INGOTS, AND ALUMINUM SHAPES WERE PRODUCED IN THE FOUNDRY. (10/30/56) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  7. Uranium perturbs signaling and iron uptake response in Arabidopsis thaliana roots.

    PubMed

    Doustaly, Fany; Combes, Florence; Fiévet, Julie B; Berthet, Serge; Hugouvieux, Véronique; Bastien, Olivier; Aranjuelo, Iker; Leonhardt, Nathalie; Rivasseau, Corinne; Carrière, Marie; Vavasseur, Alain; Renou, Jean-Pierre; Vandenbrouck, Yves; Bourguignon, Jacques

    2014-04-01

    Uranium is a natural element which is mainly redistributed in the environment due to human activity, including accidents and spillages. Plants may be useful in cleaning up after incidents, although little is yet known about the relationship between metal speciation and plant response. Here, J-Chess modeling was used to predict U speciation and exposure conditions affecting U bioavailability for plants. The model was confirmed by exposing Arabidopsis thaliana plants to U under hydroponic conditions. The early root response was characterized using complete Arabidopsis transcriptome microarrays (CATMA). Expression of 111 genes was modified at the three timepoints studied. The associated biological processes were further examined by real-time quantitative RT-PCR. Annotation revealed that oxidative stress, cell wall and hormone biosynthesis, and signaling pathways (including phosphate signaling) were affected by U exposure. The main actors in iron uptake and signaling (IRT1, FRO2, AHA2, AHA7 and FIT1) were strongly down-regulated upon exposure to uranyl. A network calculated using IRT1, FRO2 and FIT1 as bait revealed a set of genes whose expression levels change under U stress. Hypotheses are presented to explain how U perturbs the iron uptake and signaling response. These results give preliminary insights into the pathways affected by uranyl uptake, which will be of interest for engineering plants to help clean areas contaminated with U.

  8. Kinetics of Uranium Extraction from Uranium Tailings by Oxidative Leaching

    NASA Astrophysics Data System (ADS)

    Zhang, Biao; Li, Mi; Zhang, Xiaowen; Huang, Jing

    2016-07-01

    Extraction of uranium from uranium tailings by oxidative leaching with hydrogen peroxide (H2O2) was studied. The effects of various extraction factors were investigated to optimize the dissolution conditions, as well as to determine the leaching kinetic parameters. The behavior of H2O2 in the leaching process was determined through scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDX) and x-ray diffraction analysis of leaching residues. Results suggest that H2O2 can significantly improve uranium extraction by decomposing the complex gangue structures in uranium tailings and by enhancing the reaction rate between uranium phases and the leaching agent. The extraction kinetics expression was changed from 1 - 3(1 - α)2/3 + 2(1 - α) = K 0(H2SO4)-0.14903(S/L)-1.80435( R o)0.20023 e -1670.93/T t ( t ≥ 5) to 1 - 3(1 - α)2/3 + 2(1 - α) = K 0(H2SO4)0.01382(S/L)-1.83275( R o)0.25763 e -1654.59/T t ( t ≥ 5) by the addition of H2O2 in the leaching process. The use of H2O2 in uranium leaching may help in extracting uranium more efficiently and rapidly from low-uranium-containing ores or tailings.

  9. FLAME DENITRATION AND REDUCTION OF URANIUM NITRATE TO URANIUM DIOXIDE

    DOEpatents

    Hedley, W.H.; Roehrs, R.J.; Henderson, C.M.

    1962-06-26

    A process is given for converting uranyl nitrate solution to uranium dioxide. The process comprises spraying fine droplets of aqueous uranyl nitrate solution into a hightemperature hydrocarbon flame, said flame being deficient in oxygen approximately 30%, retaining the feed in the flame for a sufficient length of time to reduce the nitrate to the dioxide, and recovering uranium dioxide. (AEC)

  10. Conversion of depleted uranium hexafluoride to a solid uranium compound

    DOEpatents

    Rothman, Alan B.; Graczyk, Donald G.; Essling, Alice M.; Horwitz, E. Philip

    2001-01-01

    A process for converting UF.sub.6 to a solid uranium compound such as UO.sub.2 and CaF. The UF.sub.6 vapor form is contacted with an aqueous solution of NH.sub.4 OH at a pH greater than 7 to precipitate at least some solid uranium values as a solid leaving an aqueous solution containing NH.sub.4 OH and NH.sub.4 F and remaining uranium values. The solid uranium values are separated from the aqueous solution of NH.sub.4 OH and NH.sub.4 F and remaining uranium values which is then diluted with additional water precipitating more uranium values as a solid leaving trace quantities of uranium in a dilute aqueous solution. The dilute aqueous solution is contacted with an ion-exchange resin to remove substantially all the uranium values from the dilute aqueous solution. The dilute solution being contacted with Ca(OH).sub.2 to precipitate CaF.sub.2 leaving dilute NH.sub.4 OH.

  11. Determination of irradiated reactor uranium in soil samples in Belarus using 236U as irradiated uranium tracer.

    PubMed

    Mironov, Vladislav P; Matusevich, Janna L; Kudrjashov, Vladimir P; Boulyga, Sergei F; Becker, J Sabine

    2002-12-01

    This work presents experimental results on the distribution of irradiated reactor uranium from fallout after the accident at Chernobyl Nuclear Power Plant (NPP) in comparison to natural uranium distribution in different soil types. Oxidation processes and vertical migration of irradiated uranium in soils typical of the 30 km relocation area around Chernobyl NPP were studied using 236U as the tracer for irradiated reactor uranium and inductively coupled plasma mass spectrometry as the analytical method for uranium isotope ratio measurements. Measurements of natural uranium yielded significant variations of its concentration in upper soil layers from 2 x 10(-7) g g(-1) to 3.4 x 10(-6) g g(-1). Concentrations of irradiated uranium in the upper 0-10 cm soil layers at the investigated sampling sites varied from 5 x 10(-12) g g(-1) to 2 x 10(-6) g g(-1) depending on the distance from Chernobyl NPP. In the majority of investigated soil profiles 78% to 97% of irradiated "Chernobyl" uranium is still contained in the upper 0-10 cm soil layers. The physical and chemical characteristics of the soil do not have any significant influence on processes of fuel particle destruction. Results obtained using carbonate leaching of 236U confirmed that more than 60% of irradiated "Chernobyl" uranium is still in a tetravalent form, ie. it is included in the fuel matrix (non-oxidized fuel UO2). The average value of the destruction rate of fuel particles determined for the Western radioactive trace (k = 0.030 +/- 0.005 yr(-1)) and for the Northern radioactive trace (k = 0.035 + 0.009 yr(-1)) coincide within experimental errors. Use of leaching of fission products in comparison to leaching of uranium for study of the destruction rate of fuel particles yielded poor coincidence due to the fact that use of fission products does not take into account differences in the chemical properties of fission products and fuel matrix (uranium).

  12. The terrestrial uranium isotope cycle.

    PubMed

    Andersen, Morten B; Elliott, Tim; Freymuth, Heye; Sims, Kenneth W W; Niu, Yaoling; Kelley, Katherine A

    2015-01-15

    Changing conditions on the Earth's surface can have a remarkable influence on the composition of its overwhelmingly more massive interior. The global distribution of uranium is a notable example. In early Earth history, the continental crust was enriched in uranium. Yet after the initial rise in atmospheric oxygen, about 2.4 billion years ago, the aqueous mobility of oxidized uranium resulted in its significant transport to the oceans and, ultimately, by means of subduction, back to the mantle. Here we explore the isotopic characteristics of this global uranium cycle. We show that the subducted flux of uranium is isotopically distinct, with high (238)U/(235)U ratios, as a result of alteration processes at the bottom of an oxic ocean. We also find that mid-ocean-ridge basalts (MORBs) have (238)U/(235)U ratios higher than does the bulk Earth, confirming the widespread pollution of the upper mantle with this recycled uranium. Although many ocean island basalts (OIBs) are argued to contain a recycled component, their uranium isotopic compositions do not differ from those of the bulk Earth. Because subducted uranium was probably isotopically unfractionated before full oceanic oxidation, about 600 million years ago, this observation reflects the greater antiquity of OIB sources. Elemental and isotope systematics of uranium in OIBs are strikingly consistent with previous OIB lead model ages, indicating that these mantle reservoirs formed between 2.4 and 1.8 billion years ago. In contrast, the uranium isotopic composition of MORB requires the convective stirring of recycled uranium throughout the upper mantle within the past 600 million years.

  13. The terrestrial uranium isotope cycle

    NASA Astrophysics Data System (ADS)

    Andersen, Morten B.; Elliott, Tim; Freymuth, Heye; Sims, Kenneth W. W.; Niu, Yaoling; Kelley, Katherine A.

    2015-01-01

    Changing conditions on the Earth's surface can have a remarkable influence on the composition of its overwhelmingly more massive interior. The global distribution of uranium is a notable example. In early Earth history, the continental crust was enriched in uranium. Yet after the initial rise in atmospheric oxygen, about 2.4 billion years ago, the aqueous mobility of oxidized uranium resulted in its significant transport to the oceans and, ultimately, by means of subduction, back to the mantle. Here we explore the isotopic characteristics of this global uranium cycle. We show that the subducted flux of uranium is isotopically distinct, with high 238U/235U ratios, as a result of alteration processes at the bottom of an oxic ocean. We also find that mid-ocean-ridge basalts (MORBs) have 238U/235U ratios higher than does the bulk Earth, confirming the widespread pollution of the upper mantle with this recycled uranium. Although many ocean island basalts (OIBs) are argued to contain a recycled component, their uranium isotopic compositions do not differ from those of the bulk Earth. Because subducted uranium was probably isotopically unfractionated before full oceanic oxidation, about 600 million years ago, this observation reflects the greater antiquity of OIB sources. Elemental and isotope systematics of uranium in OIBs are strikingly consistent with previous OIB lead model ages, indicating that these mantle reservoirs formed between 2.4 and 1.8 billion years ago. In contrast, the uranium isotopic composition of MORB requires the convective stirring of recycled uranium throughout the upper mantle within the past 600 million years.

  14. Hypertension and hematologic parameters in a community near a uranium processing facility

    SciTech Connect

    Wagner, Sara E.; Burch, James B.; Bottai, Matteo; Pinney, Susan M.; Puett, Robin; Porter, Dwayne; Vena, John E.; Hebert, James R.

    2010-11-15

    Background: Environmental uranium exposure originating as a byproduct of uranium processing can impact human health. The Fernald Feed Materials Production Center functioned as a uranium processing facility from 1951 to 1989, and potential health effects among residents living near this plant were investigated via the Fernald Medical Monitoring Program (FMMP). Methods: Data from 8216 adult FMMP participants were used to test the hypothesis that elevated uranium exposure was associated with indicators of hypertension or changes in hematologic parameters at entry into the program. A cumulative uranium exposure estimate, developed by FMMP investigators, was used to classify exposure. Systolic and diastolic blood pressure and physician diagnoses were used to assess hypertension; and red blood cells, platelets, and white blood cell differential counts were used to characterize hematology. The relationship between uranium exposure and hypertension or hematologic parameters was evaluated using generalized linear models and quantile regression for continuous outcomes, and logistic regression or ordinal logistic regression for categorical outcomes, after adjustment for potential confounding factors. Results: Of 8216 adult FMMP participants 4187 (51%) had low cumulative uranium exposure, 1273 (15%) had moderate exposure, and 2756 (34%) were in the high (>0.50 Sievert) cumulative lifetime uranium exposure category. Participants with elevated uranium exposure had decreased white blood cell and lymphocyte counts and increased eosinophil counts. Female participants with higher uranium exposures had elevated systolic blood pressure compared to women with lower exposures. However, no exposure-related changes were observed in diastolic blood pressure or hypertension diagnoses among female or male participants. Conclusions: Results from this investigation suggest that residents in the vicinity of the Fernald plant with elevated exposure to uranium primarily via inhalation exhibited

  15. Urinary excretion of uranium in adult inhabitants of the Czech Republic.

    PubMed

    Malátová, Irena; Bečková, Věra; Kotík, Lukáš

    2016-02-01

    The main aim of this study was to determine and evaluate urinary excretion of uranium in the general public of the Czech Republic. This value should serve as a baseline for distinguishing possible increase in uranium content in population living near legacy sites of mining and processing uranium ores and also to help to distinguish the proportion of the uranium content in urine among uranium miners resulting from inhaled dust. The geometric mean of the uranium concentration in urine of 74 inhabitants of the Czech Republic was 0.091 mBq/L (7.4 ng/L) with the 95% confidence interval 0.071-0.12 mBq/L (5.7-9.6 ng/L) respectively. The geometric mean of the daily excretion was 0.15 mBq/d (12.4 ng/d) with the 95% confidence interval 0.12-0.20 mBq/d (9.5-16.1 ng/d) respectively. Despite the legacy of uranium mines and plants processing uranium ore in the Czech Republic, the levels of uranium in urine and therefore, also human body content of uranium, is similar to other countries, esp. Germany, Slovenia and USA. Significant difference in the daily urinary excretion of uranium was found between individuals using public supply and private water wells as a source of drinking water. Age dependence of daily urinary excretion of uranium was not found. Mean values and their range are comparable to other countries, esp. Germany, Slovenia and USA.

  16. The ultimate disposition of depleted uranium

    SciTech Connect

    Not Available

    1990-12-01

    Significant amounts of the depleted uranium (DU) created by past uranium enrichment activities have been sold, disposed of commercially, or utilized by defense programs. In recent years, however, the demand for DU has become quite small compared to quantities available, and within the US Department of Energy (DOE) there is concern for any risks and/or cost liabilities that might be associated with the ever-growing inventory of this material. As a result, Martin Marietta Energy Systems, Inc. (Energy Systems), was asked to review options and to develop a comprehensive plan for inventory management and the ultimate disposition of DU accumulated at the gaseous diffusion plants (GDPs). An Energy Systems task team, under the chairmanship of T. R. Lemons, was formed in late 1989 to provide advice and guidance for this task. This report reviews options and recommends actions and objectives in the management of working inventories of partially depleted feed (PDF) materials and for the ultimate disposition of fully depleted uranium (FDU). Actions that should be considered are as follows. (1) Inspect UF{sub 6} cylinders on a semiannual basis. (2) Upgrade cylinder maintenance and storage yards. (3) Convert FDU to U{sub 3}O{sub 8} for long-term storage or disposal. This will include provisions for partial recovery of costs to offset those associated with DU inventory management and the ultimate disposal of FDU. Another recommendation is to drop the term tails'' in favor of depleted uranium'' or DU'' because the tails'' label implies that it is waste.'' 13 refs.

  17. Spectroscopic Evidence of Uranium Immobilization in Acidic ...

    EPA Pesticide Factsheets

    Biogeochemistry of uranium in wetlands plays important roles in U immobilization in storage ponds of U mining and processing facilities but has not been well understood. The objective of this work was to study molecular mechanisms responsible for high U retention by Savannah River Site (SRS) wetland sediments under varying redox and acidic (pH = 2.6-5.8) conditions using U L3-edge X-ray absorption spectroscopy. Uranium in the SRS wetland sediments existed primarily as U(VI) bonded as a bidentate to carboxylic sites (U-C bond distance at ~2.88 Å), rather than phenolic or other sites of natural organic matter (NOM). In microcosms simulating the SRS wetland process, U immobilization on roots was 2 orders of magnitude higher than on the adjacent brown or more distant white sands in which U was U(VI). Uranium on the roots were both U(IV) and U(VI), which were bonded as a bidentate to carbon, but the U(VI) may also form a U phosphate mineral. After 140 days of air exposure, all U(IV) was reoxidized to U(VI) but remained as a bidentate bonding to carbon. This study demonstrated NOM and plant roots can highly immobilize U(VI) in the SRS acidic sediments, which has significant implication on the long-term stewardship of U-contaminated wetlands. There were several former U processing facilities at the Savannah River Site (SRS), Aiken, SC. As a result of their operations, uranium has entered the surrounding environments. For example, approximately 45,000 kg o

  18. Engineering assessment of inactive uranium mill tailings

    SciTech Connect

    Not Available

    1981-07-01

    The Grand Junction site has been reevaluated in order to revise the October 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Grand Junction, Colorado. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.9 million tons of tailings at the Grand Junction site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation are also factors. The eight alternative actions presented herein range from millsite and off-site decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through VIII). Cost estimates for the eight options range from about $10,200,000 for stabilization in-place to about $39,500,000 for disposal in the DeBeque area, at a distance of about 35 mi, using transportation by rail. If transportation to DeBeque were by truck, the cost estimated to be about $41,900,000. Three principal alternatives for the reprocessing of the Grand Junction tailings were examined: (a) heap leaching; (b) treatment at an existing mill; and (c) reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $200/lb by heap leach and $150/lb by conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery appears not to be economically attractive.

  19. Solubility measurement of uranium in uranium-contaminated soils

    SciTech Connect

    Lee, S.Y.; Elless, M.; Hoffman, F.

    1993-08-01

    A short-term equilibration study involving two uranium-contaminated soils at the Fernald site was conducted as part of the In Situ Remediation Integrated Program. The goal of this study is to predict the behavior of uranium during on-site remediation of these soils. Geochemical modeling was performed on the aqueous species dissolved from these soils following the equilibration study to predict the on-site uranium leaching and transport processes. The soluble levels of total uranium, calcium, magnesium, and carbonate increased continually for the first four weeks. After the first four weeks, these components either reached a steady-state equilibrium or continued linearity throughout the study. Aluminum, potassium, and iron, reached a steady-state concentration within three days. Silica levels approximated the predicted solubility of quartz throughout the study. A much higher level of dissolved uranium was observed in the soil contaminated from spillage of uranium-laden solvents and process effluents than in the soil contaminated from settling of airborne uranium particles ejected from the nearby incinerator. The high levels observed for soluble calcium, magnesium, and bicarbonate are probably the result of magnesium and/or calcium carbonate minerals dissolving in these soils. Geochemical modeling confirms that the uranyl-carbonate complexes are the most stable and dominant in these solutions. The use of carbonate minerals on these soils for erosion control and road construction activities contributes to the leaching of uranium from contaminated soil particles. Dissolved carbonates promote uranium solubility, forming highly mobile anionic species. Mobile uranium species are contaminating the groundwater underlying these soils. The development of a site-specific remediation technology is urgently needed for the FEMP site.

  20. Thorium, uranium and rare earth elements content in lanthanide concentrate (LC) and water leach purification (WLP) residue of Lynas advanced materials plant (LAMP)

    SciTech Connect

    AL-Areqi, Wadeeah M. Majid, Amran Ab. Sarmani, Sukiman

    2014-02-12

    Lynas Advanced Materials Plant (LAMP) has been licensed to produce the rare earths elements since early 2013 in Malaysia. LAMP processes lanthanide concentrate (LC) to extract rare earth elements and subsequently produce large volumes of water leach purification (WLP) residue containing naturally occurring radioactive material (NORM). This residue has been rising up the environmental issue because it was suspected to accumulate thorium with significant activity concentration and has been classified as radioactive residue. The aim of this study is to determine Th-232, U-238 and rare earth elements in lanthanide concentrate (LC) and water leach purification (WLP) residue collected from LAMP and to evaluate the potential radiological impacts of the WLP residue on the environment. Instrumental Neutron Activation Analysis and γ-spectrometry were used for determination of Th, U and rare earth elements concentrations. The results of this study found that the concentration of Th in LC was 1289.7 ± 129 ppm (5274.9 ± 527.6Bq/kg) whereas the Th and U concentrations in WLP were determined to be 1952.9±17.6 ppm (7987.4 ± 71.9 Bq/kg) and 17.2 ± 2.4 ppm respectively. The concentrations of Th and U in LC and WLP samples determined by γ- spectrometry were 1156 ppm (4728 ± 22 Bq/kg) and 18.8 ppm and 1763.2 ppm (7211.4 Bq/kg) and 29.97 ppm respectively. This study showed that thorium concentrations were higher in WLP compare to LC. This study also indicate that WLP residue has high radioactivity of {sup 232}Th compared to Malaysian soil natural background (63 - 110 Bq/kg) and come under preview of Act 304 and regulations. In LC, the Ce and Nd concentrations determined by INAA were 13.2 ± 0.6% and 4.7 ± 0.1% respectively whereas the concentrations of La, Ce, Nd and Sm in WLP were 0.36 ± 0.04%, 1.6%, 0.22% and 0.06% respectively. This result showed that some amount of rare earth had not been extracted and remained in the WLP and may be considered to be reextracted.

  1. Thorium, uranium and rare earth elements content in lanthanide concentrate (LC) and water leach purification (WLP) residue of Lynas advanced materials plant (LAMP)

    NASA Astrophysics Data System (ADS)

    AL-Areqi, Wadeeah M.; Majid, Amran Ab.; Sarmani, Sukiman

    2014-02-01

    Lynas Advanced Materials Plant (LAMP) has been licensed to produce the rare earths elements since early 2013 in Malaysia. LAMP processes lanthanide concentrate (LC) to extract rare earth elements and subsequently produce large volumes of water leach purification (WLP) residue containing naturally occurring radioactive material (NORM). This residue has been rising up the environmental issue because it was suspected to accumulate thorium with significant activity concentration and has been classified as radioactive residue. The aim of this study is to determine Th-232, U-238 and rare earth elements in lanthanide concentrate (LC) and water leach purification (WLP) residue collected from LAMP and to evaluate the potential radiological impacts of the WLP residue on the environment. Instrumental Neutron Activation Analysis and γ-spectrometry were used for determination of Th, U and rare earth elements concentrations. The results of this study found that the concentration of Th in LC was 1289.7 ± 129 ppm (5274.9 ± 527.6Bq/kg) whereas the Th and U concentrations in WLP were determined to be 1952.9±17.6 ppm (7987.4 ± 71.9 Bq/kg) and 17.2 ± 2.4 ppm respectively. The concentrations of Th and U in LC and WLP samples determined by γ- spectrometry were 1156 ppm (4728 ± 22 Bq/kg) & 18.8 ppm and 1763.2 ppm (7211.4 Bq/kg) &29.97 ppm respectively. This study showed that thorium concentrations were higher in WLP compare to LC. This study also indicate that WLP residue has high radioactivity of 232Th compared to Malaysian soil natural background (63 - 110 Bq/kg) and come under preview of Act 304 and regulations. In LC, the Ce and Nd concentrations determined by INAA were 13.2 ± 0.6% and 4.7 ± 0.1% respectively whereas the concentrations of La, Ce, Nd and Sm in WLP were 0.36 ± 0.04%, 1.6%, 0.22% and 0.06% respectively. This result showed that some amount of rare earth had not been extracted and remained in the WLP and may be considered to be reextracted.

  2. High pressure elasticity and thermal properties of depleted uranium

    DOE PAGES

    Jacobsen, M. K.; Velisavljevic, N.

    2016-04-28

    Studies of the phase diagram of uranium have revealed a wealth of high pressure and temperature phases. Under ambient conditions the crystal structure is well defined up to 100 gigapascals (GPa), but very little information on thermal conduction or elasticity is available over this same range. This work has applied ultrasonic interferometry to determine the elasticity, mechanical, and thermal properties of depleted uranium to 4.5 GPa. Results show general strengthening with applied load, including an overall increase in acoustic thermal conductivity. Further implications are discussed within. Lastly, this work presents the first high pressure studies of the elasticity and thermalmore » properties of depleted uranium metal and the first real-world application of a previously developed containment system for making such measurements.« less

  3. High pressure elasticity and thermal properties of depleted uranium

    SciTech Connect

    Jacobsen, M. K. Velisavljevic, N.

    2016-04-28

    Studies of the phase diagram of uranium have revealed a wealth of high pressure and temperature phases. Under ambient conditions the crystal structure is well defined up to 100 gigapascals (GPa), but very little information on thermal conduction or elasticity is available over this same range. This work has applied ultrasonic interferometry to determine the elasticity, mechanical, and thermal properties of depleted uranium to 4.5 GPa. Results show general strengthening with applied load, including an overall increase in acoustic thermal conductivity. Further implications are discussed within. This work presents the first high pressure studies of the elasticity and thermal properties of depleted uranium metal and the first real-world application of a previously developed containment system for making such measurements.

  4. High pressure elasticity and thermal properties of depleted uranium

    NASA Astrophysics Data System (ADS)

    Jacobsen, M. K.; Velisavljevic, N.

    2016-04-01

    Studies of the phase diagram of uranium have revealed a wealth of high pressure and temperature phases. Under ambient conditions the crystal structure is well defined up to 100 gigapascals (GPa), but very little information on thermal conduction or elasticity is available over this same range. This work has applied ultrasonic interferometry to determine the elasticity, mechanical, and thermal properties of depleted uranium to 4.5 GPa. Results show general strengthening with applied load, including an overall increase in acoustic thermal conductivity. Further implications are discussed within. This work presents the first high pressure studies of the elasticity and thermal properties of depleted uranium metal and the first real-world application of a previously developed containment system for making such measurements.

  5. METHOD OF SEPARATING URANIUM SUSPENSIONS

    DOEpatents

    Wigner, E.P.; McAdams, W.A.

    1958-08-26

    A process is presented for separating colloidally dissed uranium oxides from the heavy water medium in upwhich they are contained. The method consists in treating such dispersions with hydrogen peroxide, thereby converting the uranium to non-colloidal UO/sub 4/, and separating the UO/sub 4/ sfter its rapid settling.

  6. SOLVENT EXTRACTION OF URANIUM VALUES

    DOEpatents

    Feder, H.M.; Ader, M.; Ross, L.E.

    1959-02-01

    A process is presented for extracting uranium salt from aqueous acidic solutions by organic solvent extraction. It consists in contacting the uranium bearing solution with a water immiscible dialkylacetamide having at least 8 carbon atoms in the molecule. Mentioned as a preferred extractant is dibutylacetamide. The organic solvent is usually used with a diluent such as kerosene or CCl/sub 4/.

  7. PLUTONIUM-URANIUM-TITANIUM ALLOYS

    DOEpatents

    Coffinberry, A.S.

    1959-07-28

    A plutonium-uranium alloy suitable for use as the fuel element in a fast breeder reactor is described. The alloy contains from 15 to 60 at.% titanium with the remainder uranium and plutonium in a specific ratio, thereby limiting the undesirable zeta phase and rendering the alloy relatively resistant to corrosion and giving it the essential characteristic of good mechanical workability.

  8. Developments in uranium in 1987

    SciTech Connect

    Chenoweth, W.L.

    1988-10-01

    Legal and political factors, imports, and low prices continued to plague the domestic uranium industry. As a result, the Secretary of Energy in 1987 declared the domestic industry to be nonviable for the third straight year. Uranium exploration expenditures in the US declined for the ninth consecutive year. In 1987, an estimated $18 million was spent on uranium exploration, including 1.9 million ft of surface drilling. This drilling was done mainly in production areas and in areas of recent discoveries. Production of uranium concentrate decreased slightly in 1987, when 12.5 million lb of uranium oxide (U/sub 3/O/sub 8/) were produced, a 7% decrease from 1986. Uranium produced from mine water, solution mining, and as the byproduct of phosphoric acid and copper production accounted for about 38% of the total production in the US. At the end of 1987, only 5 uranium mills were operating in the US. The large, high-grade reserves being discovered and developed in Saskatchewan will enable Canada to dominate the world market for many years. Development of the Olympic Dam deposit continued in Australia and will being production in 1988. US uranium production is expected to increase slightly in 1988, as a new open-pit mine begin production. 3 figs., 2 tabs.

  9. ELECTRODEPOSITION OF NICKEL ON URANIUM

    DOEpatents

    Gray, A.G.

    1958-08-26

    A method is described for preparing uranium objects prior to nickel electroplating. The process consiats in treating the surface of the uranium with molten ferric chloride hexahydrate, at a slightiy elevated temperature. This treatment etches the metal surface providing a structure suitable for the application of adherent electrodeposits and at the same time plates the surface with a thin protective film of iron.

  10. Aluminosilicate Precipitation Impact on Uranium

    SciTech Connect

    WILMARTH, WILLIAM

    2006-03-10

    Experiments have been conducted to examine the fate of uranium during the formation of sodium aluminosilicate (NAS) when wastes containing high aluminate concentrations are mixed with wastes of high silicate concentration. Testing was conducted at varying degrees of uranium saturation. Testing examined typical tank conditions, e.g., stagnant, slightly elevated temperature (50 C). The results showed that under sub-saturated conditions uranium is not removed from solution to any large extent in both simulant testing and actual tank waste testing. This aspect was not thoroughly understood prior to this work and was necessary to avoid criticality issues when actual tank wastes were aggregated. There are data supporting a small removal due to sorption of uranium on sites in the NAS. Above the solubility limit the data are clear that a reduction in uranium concentration occurs concomitant with the formation of aluminosilicate. This uranium precipitation is fairly rapid and ceases when uranium reaches its solubility limit. At the solubility limit, it appears that uranium is not affected, but further testing might be warranted.

  11. Uranium extraction: Fuel from seawater

    DOE PAGES

    Tsouris, Costas; Oak Ridge National Lab.

    2017-02-17

    Over four billion tonnes of uranium are currently in the oceans that could be harvested for nuclear fuel, but current capture methods have limited performance and reusability. Now, an electrochemical method using modified carbon electrodes is shown to be promising for the extraction of uranium from seawater.

  12. METHOD OF ELECTROPLATING ON URANIUM

    DOEpatents

    Rebol, E.W.; Wehrmann, R.F.

    1959-04-28

    This patent relates to a preparation of metallic uranium surfaces for receiving coatings, particularly in order to secure adherent electroplated coatings upon uranium metal. In accordance with the invention the uranium surface is pretreated by degreasing in trichloroethylene, followed by immersion in 25 to 50% nitric acid for several minutes, and then rinsed with running water, prior to pickling in trichloroacetic acid. The last treatment is best accomplished by making the uranium the anode in an aqueous solution of 50 per cent by weight trichloroacetic acid until work-distorted crystals or oxide present on the metal surface have been removed and the basic crystalline structure of the base metal has been exposed. Following these initial steps the metallic uranium is rinsed in dilute nitric acid and then electroplated with nickel. Adnerent firmly-bonded coatings of nickel are obtained.

  13. Superconductivity in uranium materials

    SciTech Connect

    Fish, Z.; Ott, H.R.

    1989-04-01

    Metallic uranium materials occupy an interesting niche that is intermediate between transition and f-electron materials. Uranium in different environments is able to span this entire range, with narrow d-bands replaced by f-bands when the U-U distances are close enough for direct f-orbital overlap (closer than the Hill spacing), and with localized f-electrons forming magnetically ordered materials in the other extreme of large U-U spacing. As the U-U spacing and, in compounds, the ligand atoms, change, an interesting continuum of physics develops connected with the changing f-character of the materials. Corresponding to changing U-U separation are large, but non-monotonic, changes of more than two orders of magnitude in the low-temperature electronic specific heat parameter /gamma/. This parameter is a measure of the electronic density of states at the Fermi level, and in the free-electron theory of metals as well as the Landau Fermi liquid, the magnetic susceptibility chi due to the conduction electrons is also proportional to the density of states at the Fermi level. It is useful to plot for various materials the measured /gamma/ versus the T /yields/ O K limiting chi to see how much the measured chi is present, so to speak, in /gamma/. The authors do this for most of the known uranium superconductors. The solid line plotted there is the free-electron expression relating /gamma/ and chi. For materials with anisotropic susceptibility, the horizontal span of values corresponds to the range of chi values.

  14. 24. VIEW OF THE SECOND FLOOR PLAN. ENRICHED URANIUM AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. VIEW OF THE SECOND FLOOR PLAN. ENRICHED URANIUM AND STAINLESS STEEL WEAPONS COMPONENT PRODUCTION-RELATED ACTIVITIES OCCURRED PRIMARILY ON THE SECOND FLOOR. THE ORIGINAL DRAWING HAS BEEN ARCHIVED ON MICROFILM. THE DRAWING WAS REPRODUCED AT THE BEST QUALITY POSSIBLE. LETTERS AND NUMBERS IN THE CIRCLES INDICATE FOOTER AND/OR COLUMN LOCATIONS. - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

  15. New Prototype Safeguards Technology Offers Improved Confidence and Automation for Uranium Enrichment Facilities

    SciTech Connect

    Brim, Cornelia P.

    2013-04-01

    An important requirement for the international safeguards community is the ability to determine the enrichment level of uranium in gas centrifuge enrichment plants and nuclear fuel fabrication facilities. This is essential to ensure that countries with nuclear nonproliferation commitments, such as States Party to the Nuclear Nonproliferation Treaty, are adhering to their obligations. However, current technologies to verify the uranium enrichment level in gas centrifuge enrichment plants or nuclear fuel fabrication facilities are technically challenging and resource-intensive. NNSA’s Office of Nonproliferation and International Security (NIS) supports the development, testing, and evaluation of future systems that will strengthen and sustain U.S. safeguards and security capabilities—in this case, by automating the monitoring of uranium enrichment in the entire inventory of a fuel fabrication facility. One such system is HEVA—hybrid enrichment verification array. This prototype was developed to provide an automated, nondestructive assay verification technology for uranium hexafluoride (UF6) cylinders at enrichment plants.

  16. Photodegradation of uranium-citrate complex with uranium recovery

    SciTech Connect

    Dodge, C.J.; Francis, A.J. )

    1994-07-01

    Upon exposure to visible light, uranyl citrate complex showed photodegradation of citric acid to acetic acid and carbon dioxide, with the precipitation of uranium as uranium trioxide (UO[sub 3][center dot]2H[sub 2]O). The initial pH and presence of oxygen affected the rate and extent of photochemical degradation of the complex, the formation of intermediate organic degradation products, and uranium speciation. Under aerobic conditions at pH 3.5, acetic, acetoacetic, 3-oxoglutaric, and malonic acids and acetone were detected; at pH 6.0, 3-oxoglutaric and acetic acids were present. The uranyl U(VI) ion was reduced to uranous U(IV) ion and was subsequently reoxidized to the hexavalent form and precipitated out of solution as uranium trioxide. Uranium trioxide precipitate was insoluble at near-neutral pH and was soluble in acidic pH (<4.1). Under anaerobic conditions, the uranyl citrate complex showed only partial (57%) degradation, and uranium was present in the reduced form as U(IV). Excess citric acid retarded the precipitation of uranium. 26 refs., 9 figs., 1 tab.

  17. 31 CFR 540.309 - Natural uranium.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Natural uranium. 540.309 Section 540.309 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF... REGULATIONS General Definitions § 540.309 Natural uranium. The term natural uranium means uranium found in...

  18. 31 CFR 540.309 - Natural uranium.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Natural uranium. 540.309 Section 540.309 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF... REGULATIONS General Definitions § 540.309 Natural uranium. The term natural uranium means uranium found in...

  19. PREPARATION OF URANIUM-ALUMINUM ALLOYS

    DOEpatents

    Moore, R.H.

    1962-09-01

    A process is given for preparing uranium--aluminum alloys from a solution of uranium halide in an about equimolar molten alkali metal halide-- aluminum halide mixture and excess aluminum. The uranium halide is reduced and the uranium is alloyed with the excess aluminum. The alloy and salt are separated from each other. (AEC)

  20. THE RECOVERY OF URANIUM FROM GAS MIXTURE

    DOEpatents

    Jury, S.H.

    1964-03-17

    A method of separating uranium from a mixture of uranium hexafluoride and other gases is described that comprises bringing the mixture into contact with anhydrous calcium sulfate to preferentially absorb the uranium hexafluoride on the sulfate. The calcium sulfate is then leached with a selective solvent for the adsorbed uranium. (AEC)

  1. Process for removing carbon from uranium

    DOEpatents

    Powell, George L.; Holcombe, Jr., Cressie E.

    1976-01-01

    Carbon contamination is removed from uranium and uranium alloys by heating in inert atmosphere to 700.degree.-1900.degree.C in effective contact with yttrium to cause carbon in the uranium to react with the yttrium. The yttrium is either in direct contact with the contaminated uranium or in indirect contact by means of an intermediate transport medium.

  2. 31 CFR 540.316 - Uranium enrichment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Uranium enrichment. 540.316 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of...

  3. 31 CFR 540.316 - Uranium enrichment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Uranium enrichment. 540.316 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of...

  4. 31 CFR 540.316 - Uranium enrichment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Uranium enrichment. 540.316 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of...

  5. 31 CFR 540.316 - Uranium enrichment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Uranium enrichment. 540.316 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of...

  6. 31 CFR 540.316 - Uranium enrichment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Uranium enrichment. 540.316 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of...

  7. Pulsed CO laser for isotope separation of uranium

    SciTech Connect

    Baranov, Igor Y.; Koptev, Andrey V.

    2012-07-30

    This article proposes a technical solution for using a CO laser facility for the industrial separation of uranium used in the production of fuel for nuclear power plants, employing a method of laser isotope separation of uranium with condensation repression in a free jet. The laser operation with nanosecond pulse irradiation can provide an acceptable efficiency in the separating unit and a high efficiency of the laser with the wavelength of 5.3 {mu}m. In the present work we also introduce a calculation model and define the parameters of a mode-locked CO laser with a RF discharge in the supersonic stream. The average pulsed CO laser power of 3 kW is sufficient for efficient industrial isotope separation of uranium in one stage.

  8. Fernald vacuum transfer system for uranium materials repackaging

    SciTech Connect

    Kaushiva, Shirley; Weekley, Clint; Molecke, Martin; Polansky, Gary

    2002-02-24

    The Fernald Environmental Management Project (FEMP) is the site of a former Department of Energy (DOE) uranium processing plant. When production was halted, many materials were left in an intermediate state. Some of this product material included enriched uranium compounds that had to be repackaged for shipment of off-site storage. This paper provides an overview, technical description, and status of a new application of existing technology, a vacuum transfer system, to repackage the uranium bearing compounds for shipment. The vacuum transfer system provides a method of transferring compounds from their current storage configuration into packages that meet the Department of Transportation (DOT) shipping requirements for fissile materials. This is a necessary activity, supporting removal of nuclear materials prior to site decontamination and decommissioning, key to the Fernald site's closure process.

  9. Method for monitoring stack gases for uranium activity

    DOEpatents

    Beverly, C.R.; Ernstberger, E.G.

    1985-07-03

    A method for monitoring the stack gases of a purge cascade of gaseous diffusion plant for uranium activity. A sample stream is taken from the stack gases and contacted with a volume of moisture-laden air for converting trace levels of uranium hexafluoride, if any, in the stack gases into particulate uranyl fluoride. A continuous strip of filter paper from a supply roll is passed through this sampling stream to intercept and gather any uranyl fluoride in the sampling stream. This filter paper is then passed by an alpha scintillation counting device where any radioactivity on the filter paper is sensed so as to provide a continuous monitoring of the gas stream for activity indicative of the uranium content in the stack gases. 1 fig.

  10. Method for monitoring stack gases for uranium activity

    DOEpatents

    Beverly, Claude R.; Ernstberger, Harold G.

    1988-01-01

    A method for monitoring the stack gases of a purge cascade of a gaseous diffusion plant for uranium activity. A sample stream is taken from the stack gases and contacted with a volume of moisture-laden air for converting trace levels of uranium hexafluoride, if any, in the stack gases into particulate uranyl fluoride. A continuous strip of filter paper from a supply roll is passed through this sampling stream to intercept and gather any uranyl fluoride in the sampling stream. This filter paper is then passed by an alpha scintillation counting device where any radioactivity on the filter paper is sensed so as to provide a continuous monitoring of the gas stream for activity indicative of the uranium content in the stack gases.

  11. Uranium mill tailings stabilization

    SciTech Connect

    Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

    1980-02-01

    Uranium mill tailings pose a potential radiation health hazard to the public. Therefore, stabilization or disposal of these tailings in a safe and environmentally sound way is needed to minimize radon exhalation and other environmental hazards. One of the most promising concepts for stabilizing U tailings is the use of asphalt emulsion to contain radon and other hazardous materials within uranium tailings. This approach is being investigated at the Pacific Northwest Laboratory. Results of these studies indicate that a radon flux reduction of greater than 99% can be obtained using either a poured-on/sprayed-on seal (3.0 to 7.0 mm thick) or an admixture seal (2.5 to 12.7 cm thick) containing about 18 wt % residual asphalt. A field test was carried out in June 1979 at the Grand Junction tailings pile in order to demonstrate the sealing process. A reduction in radon flux ranging from 4.5 to greater than 99% (76% average) was achieved using a 15.2-cm (6-in.) admix seal with a sprayed-on top coat. A hydrostatic stabilizer was used to apply the admix. Following compaction, a spray coat seal was applied over the admix as the final step in construction of a radon seal. Overburden was applied to provide a protective soil layer over the seal. Included in part of the overburden was a herbicide to prevent root penetration.

  12. Uranium in river water

    SciTech Connect

    Palmer, M.R. ); Edmond, J.M. )

    1993-10-01

    The concentration of dissolved uranium has been determined in over 250 river waters from the Orinoco, Amazon, and Ganges basins. Uranium concentrations are largely determined by dissolution of limestones, although weathering of black shales represents an important additional source in some basins. In shield terrains the level of dissolved U is transport limited. Data from the Amazon indicate that floodplains do not represent a significant source of U in river waters. In addition, the authors have determined dissolved U levels in forty rivers from around the world and coupled these data with previous measurements to obtain an estimate for the global flux of dissolved U to the oceans. The average concentration of U in river waters is 1.3 nmol/kg, but this value is biased by very high levels observed in the Ganges-Brahmaputra and Yellow rivers. When these river systems are excluded from the budget, the global average falls to 0.78 nmol/kg. The global riverine U flux lies in the range of 3-6 [times] 10[sup 7] mol/yr. The major uncertainty that restricts the accuracy of this estimate (and that of all other dissolved riverine fluxes) is the difficulty in obtaining representative samples from rivers which show large seasonal and annual variations in runoff and dissolved load.

  13. Standoff Detection of Uranium and its Isotopes by Femtosecond Filament Laser Ablation Molecular Isotopic Spectrometry

    DOE PAGES

    Hartig, Kyle C.; Ghebregziabher, Isaac; Jovanovic, Igor

    2017-03-08

    The ability to perform not only elementally but also isotopically sensitive detection and analysis at standoff distances is important for remote sensing applications in diverse ares, such as nuclear nonproliferation, environmental monitoring, geophysics, and planetary science. We demonstrate isotopically sensitive real-time standoff detection of uranium by the use of femtosecond filament-induced laser ablation molecular isotopic spectrometry. A uranium oxide molecular emission isotope shift of 0.05 ± 0.007 nm is reported at 593.6 nm. We implement both spectroscopic and acoustic diagnostics to characterize the properties of uranium plasma generated at different filament- uranium interaction points. The resulting uranium oxide emission exhibitsmore » a nearly constant signal-to-background ratio over the length of the filament, unlike the uranium atomic and ionic emission, for which the signal-to-background ratio varies significantly along the filament propagation. This is explained by the different rates of increase of plasma density and uranium oxide density along the filament length resulting from spectral and temporal evolution of the filament along its propagation. Lastly, the results provide a basis for the optimal use of filaments for standoff detection and analysis of uranium isotopes and indicate the potential of the technique for a wider range of remote sensing applications that require isotopic sensitivity.« less

  14. Standoff Detection of Uranium and its Isotopes by Femtosecond Filament Laser Ablation Molecular Isotopic Spectrometry.

    PubMed

    Hartig, Kyle C; Ghebregziabher, Isaac; Jovanovic, Igor

    2017-03-08

    The ability to perform not only elementally but also isotopically sensitive detection and analysis at standoff distances is impor-tant for remote sensing applications in diverse ares, such as nuclear nonproliferation, environmental monitoring, geophysics, and planetary science. We demonstrate isotopically sensitive real-time standoff detection of uranium by the use of femtosecond filament-induced laser ablation molecular isotopic spectrometry. A uranium oxide molecular emission isotope shift of 0.05 ± 0.007 nm is reported at 593.6 nm. We implement both spectroscopic and acoustic diagnostics to characterize the properties of uranium plasma generated at different filament-uranium interaction points. The resulting uranium oxide emis-sion exhibits a nearly constant signal-to-background ratio over the length of the filament, unlike the uranium atomic and ionic emission, for which the signal-to-background ratio varies significantly along the filament propagation. This is explained by the different rates of increase of plasma density and uranium oxide density along the filament length resulting from spectral and temporal evolution of the filament along its propagation. The results provide a basis for the optimal use of filaments for standoff detection and analysis of uranium isotopes and indicate the potential of the technique for a wider range of remote sensing applications that require isotopic sensitivity.

  15. Standoff Detection of Uranium and its Isotopes by Femtosecond Filament Laser Ablation Molecular Isotopic Spectrometry

    PubMed Central

    Hartig, Kyle C.; Ghebregziabher, Isaac; Jovanovic, Igor

    2017-01-01

    The ability to perform not only elementally but also isotopically sensitive detection and analysis at standoff distances is impor-tant for remote sensing applications in diverse ares, such as nuclear nonproliferation, environmental monitoring, geophysics, and planetary science. We demonstrate isotopically sensitive real-time standoff detection of uranium by the use of femtosecond filament-induced laser ablation molecular isotopic spectrometry. A uranium oxide molecular emission isotope shift of 0.05 ± 0.007 nm is reported at 593.6 nm. We implement both spectroscopic and acoustic diagnostics to characterize the properties of uranium plasma generated at different filament-uranium interaction points. The resulting uranium oxide emis-sion exhibits a nearly constant signal-to-background ratio over the length of the filament, unlike the uranium atomic and ionic emission, for which the signal-to-background ratio varies significantly along the filament propagation. This is explained by the different rates of increase of plasma density and uranium oxide density along the filament length resulting from spectral and temporal evolution of the filament along its propagation. The results provide a basis for the optimal use of filaments for standoff detection and analysis of uranium isotopes and indicate the potential of the technique for a wider range of remote sensing applications that require isotopic sensitivity. PMID:28272450

  16. Standoff Detection of Uranium and its Isotopes by Femtosecond Filament Laser Ablation Molecular Isotopic Spectrometry

    NASA Astrophysics Data System (ADS)

    Hartig, Kyle C.; Ghebregziabher, Isaac; Jovanovic, Igor

    2017-03-01

    The ability to perform not only elementally but also isotopically sensitive detection and analysis at standoff distances is impor-tant for remote sensing applications in diverse ares, such as nuclear nonproliferation, environmental monitoring, geophysics, and planetary science. We demonstrate isotopically sensitive real-time standoff detection of uranium by the use of femtosecond filament-induced laser ablation molecular isotopic spectrometry. A uranium oxide molecular emission isotope shift of 0.05 ± 0.007 nm is reported at 593.6 nm. We implement both spectroscopic and acoustic diagnostics to characterize the properties of uranium plasma generated at different filament-uranium interaction points. The resulting uranium oxide emis-sion exhibits a nearly constant signal-to-background ratio over the length of the filament, unlike the uranium atomic and ionic emission, for which the signal-to-background ratio varies significantly along the filament propagation. This is explained by the different rates of increase of plasma density and uranium oxide density along the filament length resulting from spectral and temporal evolution of the filament along its propagation. The results provide a basis for the optimal use of filaments for standoff detection and analysis of uranium isotopes and indicate the potential of the technique for a wider range of remote sensing applications that require isotopic sensitivity.

  17. 20. AERIAL VIEW OF THE ROCKY FLATS PLANT LOOKING NORTHEAST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. AERIAL VIEW OF THE ROCKY FLATS PLANT LOOKING NORTHEAST. THE PLANT WAS COMPOSED OF FOUR WIDELY SEPARATED AREAS, EACH ONE PERFORMING A DIFFERENT TYPE OF WORK. PLANT A (44), SOUTHWEST, FABRICATED PARTS FROM DEPLETED URANIUM, PLANT B (81), SOUTH, WAS ENRICHED URANIUM OPERATIONS, PLANT C (71), NORTH, PLUTONIUM OPERATIONS, AND PLANT D (91), EAST, WAS FINAL ASSEMBLY, SHIPPING AND RECEIVING (2/6/66). - Rocky Flats Plant, Bounded by Indiana Street & Routes 93, 128 & 72, Golden, Jefferson County, CO

  18. ELUTION OF URANIUM FROM RESIN

    DOEpatents

    McLEan, D.C.

    1959-03-10

    A method is described for eluting uranium from anion exchange resins so as to decrease vanadium and iron contamination and permit recycle of the major portion of the eluats after recovery of the uranium. Diminution of vanadium and iron contamination of the major portion of the uranium is accomplished by treating the anion exchange resin, which is saturated with uranium complex by adsorption from a sulfuric acid leach liquor from an ore bearing uranium, vanadium and iron, with one column volume of eluant prepared by passing chlorine into ammonium hydroxide until the chloride content is about 1 N and the pH is about 1. The resin is then eluted with 8 to 9 column volumes of 0.9 N ammonium chloride--0.1 N hydrochloric acid solution. The eluants are collected separately and treated with ammonia to precipitate ammonium diuranate which is filtered therefrom. The uranium salt from the first eluant is contaminated with the major portion of ths vanadium and iron and is reworked, while the uranium recovered from the second eluant is relatively free of the undesirable vanadium and irons. The filtrate from the first eluant portion is discarded. The filtrate from the second eluant portion may be recycled after adding hydrochloric acid to increase the chloride ion concentration and adjust the pH to about 1.

  19. Separation of Depleted Uranium Fragments from Gun Test Catchment. Volume 3. Economic Comparison of Depleted Uranium Disposal Options for Elgin AFB Gun Test Facility

    DTIC Science & Technology

    1993-12-30

    plant in Jonesborough, Tennessee. The Aerojet plant reduces depleted UF4 (green salt) to metallic uranium . They are also capable of recycling DU and in...material to metallic uranium is probably less at the Aerojet facility. The cost of packaging and transporting DU fragments to a DU manufacturing facility...report. The DOE internal value of depleted UF6 is only $2.50/kg DU. However, at the Oak Ridge Y-12 Plant, it costs $200/kg DU to reduce the UF to metallic

  20. An artificially constructed Syngonium podophyllum-Aspergillus niger combinate system for removal of uranium from wastewater.

    PubMed

    He, Jia-dong; Wang, Yong-dong; Hu, Nan; Ding, Dexin; Sun, Jing; Deng, Qin-wen; Li, Chang-wu; Xu, Fei

    2015-12-01

    Aspergillus niger was inoculated to the roots of five plants, and the Syngonium podophyllum-A. niger combinate system (SPANCS) was found to be the most effective in removing uranium from hydroponic liquid with initial uranium concentration of 5 mg L(-1). Furthermore, the hydroponic experiments on the removal of uranium from the hydroponic liquids with initial uranium concentrations of 0.5, 1.0, and 3.0 mg L(-1) by the SPANCS were conducted, the inhibitory effect of A. niger on the growth of S. podophyllum in the SPANCS was studied, the accumulation characteristics of uranium by S. podophyllum in the SPANCS were analyzed, and the Fourier transform infrared (FT-IR) and extended X-ray absorption fine structure (EXAFS) spectra were measured. The results show that the removal of uranium by the SPANCS from the hydroponic liquids with initial uranium concentrations of 0.5, 1.0, and 3.0 mg L(-1) reached 98.20, 97.90, and 98.50%, respectively, after 37 days of accumulation of uranium; that the uranium concentrations in the hydroponic liquids decreased to 0.009, 0.021, and 0.045 mg L(-1), respectively, which are lower than the stipulated concentration for discharge of 0.050 mg L(-1) by the People's Republic of China; that A. niger helped to generate more groups in the root of S. podophyllum which can improve the complexing capability of S. podophyllum for uranium; and that the uranium accumulated in the root of S. podophyllum was in the form of phosphate uranyl and carboxylic uranyl.

  1. Cola soft drinks for evaluating the bioaccessibility of uranium in contaminated mine soils.

    PubMed

    Lottermoser, Bernd G; Schnug, Ewald; Haneklaus, Silvia

    2011-08-15

    There is a rising need for scientifically sound and quantitative as well as simple, rapid, cheap and readily available soil testing procedures. The purpose of this study was to explore selected soft drinks (Coca-Cola Classic®, Diet Coke®, Coke Zero®) as indicators of bioaccessible uranium and other trace elements (As, Ce, Cu, La, Mn, Ni, Pb, Th, Y, Zn) in contaminated soils of the Mary Kathleen uranium mine site, Australia. Data of single extraction tests using Coca-Cola Classic®, Diet Coke® and Coke Zero® demonstrate that extractable arsenic, copper, lanthanum, manganese, nickel, yttrium and zinc concentrations correlate significantly with DTPA- and CaCl₂-extractable metals. Moreover, the correlation between DTPA-extractable uranium and that extracted using Coca-Cola Classic® is close to unity (+0.98), with reduced correlations for Diet Coke® (+0.66) and Coke Zero® (+0.55). Also, Coca-Cola Classic® extracts uranium concentrations near identical to DTPA, whereas distinctly higher uranium fractions were extracted using Diet Coke® and Coke Zero®. Results of this study demonstrate that the use of Coca-Cola Classic® in single extraction tests provided an excellent indication of bioaccessible uranium in the analysed soils and of uranium uptake into leaves and stems of the Sodom apple (Calotropis procera). Moreover, the unconventional reagent is superior in terms of availability, costs, preparation and disposal compared to traditional chemicals. Contaminated site assessments and rehabilitation of uranium mine sites require a solid understanding of the chemical speciation of environmentally significant elements for estimating their translocation in soils and plant uptake. Therefore, Cola soft drinks have potential applications in single extraction tests of uranium contaminated soils and may be used for environmental impact assessments of uranium mine sites, nuclear fuel processing plants and waste storage and disposal facilities. Copyright © 2011 Elsevier

  2. Technology for increasing the uranium-235 isotopic abundance in natural uranium feed on a productive scale

    SciTech Connect

    Evans, E.C.

    1985-04-19

    First, the uses of enriched uranium are discussed, then the technologies for enriching uranium, how these technologies are developed and applied, and the current and future supplies of enriched uranium compared to forecasts of demand are explained. 29 figs.

  3. Determination of uranium in zircon

    USGS Publications Warehouse

    Cuttitta, F.; Daniels, G.J.

    1959-01-01

    A routine fluorimetric procedure is described for the determination of trace amounts of uranium in zircon. It employs the direct extraction of uranyl nitrate with ethyl acetate using phosphate as a retainer for zirconium. Submicrogram amounts or uranium are separated in the presence of 100,000 times the amount of zirconium. The modified procedure has been worked out using synthetic mixtures of known composition and zircon. Results of analyses have an accuracy of 97-98% of the contained uranium and a standard deviation of less than 2.5%. ?? 1959.

  4. URANIUM RECOVERY FROM NUCLEAR FUEL

    DOEpatents

    Vogel, R.C.; Rodger, W.A.

    1962-04-24

    A process of recovering uranium from a UF/sub 4/-NaFZrF/sub 4/ mixture by spraying the molten mixture at about 200 deg C in nitrogen of super- atmospheric pressure into droplets not larger than 100 microns, and contacting the molten droplets with fluorine at about 200 deg C for 0.01 to 10 seconds in a container the walls of which have a temperature below the melting point of the mixture is described. Uranium hexafluoride is formed and volatilized and the uranium-free salt is solidified. (AEC)

  5. SEPARATION OF URANIUM FROM THORIUM

    DOEpatents

    Hellman, N.N.

    1959-07-01

    A process is presented for separating uranium from thorium wherein the ratio of thorium to uranium is between 100 to 10,000. According to the invention the thoriumuranium mixture is dissolved in nitric acid, and the solution is prepared so as to obtain the desired concentration within a critical range of from 4 to 8 N with regard to the total nitrate due to thorium nitrate, with or without nitric acid or any nitrate salting out agent. The solution is then contacted with an ether, such as diethyl ether, whereby uranium is extracted into ihe organic phase while thorium remains in the aqueous phase.

  6. Profile of World Uranium Enrichment Programs-2009

    SciTech Connect

    Laughter, Mark D

    2009-04-01

    It is generally agreed that the most difficult step in building a nuclear weapon is acquiring fissile material, either plutonium or highly enriched uranium (HEU). Plutonium is produced in a nuclear reactor, whereas HEU is produced using a uranium enrichment process. Enrichment is also an important step in the civil nuclear fuel cycle, in producing low enriched uranium (LEU) for use as fuel for nuclear reactors to generate electricity. However, the same equipment used to produce LEU for nuclear reactor fuel can also be used to produce HEU for weapons. Safeguards at an enrichment plant are the array of assurances and verification techniques that ensure uranium is not diverted or enriched to HEU. There are several techniques for enriching uranium. The two most prevalent are gaseous diffusion, which uses older technology and requires a lot of energy, and gas centrifuge separation, which uses more advanced technology and is more energy efficient. Gaseous diffusion plants (GDPs) provide about 40% of current world enrichment capacity but are being phased out as newer gas centrifuge enrichment plants (GCEPs) are constructed. Estimates of current and future enrichment capacity are always approximate, due to the constant upgrades, expansions, and shutdowns occurring at enrichment plants, largely determined by economic interests. Currently, the world enrichment capacity is approximately 56 million kilogram separative work units (SWU) per year, with 22.5 million in gaseous diffusion and more than 33 million in gas centrifuge plants. Another 34 million SWU/year of capacity is under construction or planned for the near future, almost entirely using gas centrifuge separation. Other less-efficient techniques have also been used in the past, including electromagnetic and aerodynamic separations, but these are considered obsolete, at least from a commercial perspective. Laser isotope separation shows promise as a possible enrichment technique of the future but has yet to be

  7. Effects of uranium mining discharges on water quality in the Puerco River basin, Arizona and New Mexico

    USGS Publications Warehouse

    Van Metre, P.C.; Gray, J.R.

    1992-01-01

    From 1967 until 1986, uranium mine dewatering increased dissolved gross alpha, gross beta, uranium and radium activities and dissolved selenium and molybdenum concentrations in the Puerco River as indicated by time trends, areal patterns involving distance from the mines and stream discharge. Additionally, increased dissolved uranium concentrations were identified in groundwater under the Puerco River from where mine discharges entered the river to approximately the Arizona-New Mexico State line about 65 km downstream. Total mass of uranium and gross alpha activity released to the Puerco River by mine dewatering were estimated as 560 Mg (560 × 106 g) and 260 Ci, respectively. In comparison, a uranium mill tailings pond spill on 16 July 1979, released an estimated 1.5 Mg of uranium and 46 Ci of gross alpha activity. Mass balance calculations for alluvial ground water indicate that most of the uranium released did not remain in solution. Sorption of uranium on sediments and uptake of uranium by plants probably removed the uranium from solution.

  8. Measurement of uranium enrichment for gaseous uranium at low pressure

    NASA Astrophysics Data System (ADS)

    Close, D. A.; Pratt, J. C.; Atwater, H. F.; Malanify, J. J.; Nixon, K. V.; Speir, L. G.

    X-ray fluorescence determines the amount of total uranium present in gaseous UF6 inside cascade header pipes of a uranium centrifuge enrichment facility. A highly collimated source, highly collimated detctor, and a very rigid, reproducible geometry are required. Two measurements of the 185.7 keV gamma ray from U-235 using two collimators determine the amount of U-235 present only in the gas phase. The ratio of the gas only U235 signal to the total uranium gas only signal is directly proportional to the enrichment of the process UF6 gas. This measurement technique is independent of the deposit that forms on a surface in contact with UF6. This measurement technique is independent of the pressure of the gaseous UF6. This technique has the required sensitivity to determine whether the process gas is of uranium enrichment less than or equal to 20% or 20%.

  9. Method of diffusive gradients in thin films (DGT) compared with other soil testing methods to predict uranium phytoavailability.

    PubMed

    Vandenhove, H; Antunes, K; Wannijn, J; Duquène, L; Van Hees, M

    2007-02-15

    The measurement of diffusive gradients in thin films (DGT) has been proposed as a surrogate for metal uptake by plants. A small-scale experiment was performed to test the predictive capacity of the DGT method with respect to uranium availability and uptake by ryegrass. Correlation analyses were performed to compare the results obtained with the DGT device with more conventional bioavailability indices - concentration of uranium in pore water or in selective extracts. Six soils with different uranium contamination history and with distinct soil characteristics were used for the availability tests and the uptake experiment. The four uranium bioavailability indices screened were highly correlated, indicating that at least partially comparable uranium pools were assessed. The uranium concentration in the pore water was a better predictor for uranium uptake by ryegrass than amounts of uranium recovered following extraction with 0.11 M CH3COOH or 0.4 M MgCl2, the fractions considered exchangeable according to, respectively, the BCR or NIST standardized sequential extraction methods. The DGT measured concentration, C(DGT), was also highly correlated with plant uptake but the significance level was sensitive to the value of the diffusion coefficient (pH depend or not) used to calculate C(DGT). From the results obtained it could not be concluded that the DGT method would have an additional value in assessing uranium bioavailability.

  10. Plant diversity moderates drought stress in grasslands: Implications from a large real-world study on (13)C natural abundances.

    PubMed

    Klaus, Valentin H; Hölzel, Norbert; Prati, Daniel; Schmitt, Barbara; Schöning, Ingo; Schrumpf, Marion; Solly, Emily F; Hänsel, Falk; Fischer, Markus; Kleinebecker, Till

    2016-10-01

    Land-use change and intensification play a key role in the current biodiversity crisis. The resulting species loss can have severe effects on ecosystem functions and services, thereby increasing ecosystem vulnerability to climate change. We explored whether land-use intensification (i.e. fertilization intensity), plant diversity and other potentially confounding environmental factors may be significantly related to water use (i.e. drought stress) of grassland plants. Drought stress was assessed using δ(13)C abundances in aboveground plant biomass of 150 grassland plots across a gradient of land-use intensity. Under water shortage, plants are forced to increasingly take up the heavier (13)C due to closing stomata leading to an enrichment of (13)C in biomass. Plants were sampled at the community level and for single species, which belong to three different functional groups (one grass, one herb, two legumes). Results show that plant diversity was significantly related to the δ(13)C signal in community, grass and legume biomass indicating that drought stress was lower under higher diversity, although this relation was not significant for the herb species under study. Fertilization, in turn, mostly increased drought stress as indicated by more positive δ(13)C values. This effect was mostly indirect by decreasing plant diversity. In line with these results, we found similar patterns in the δ(13)C signal of the organic matter in the topsoil, indicating a long history of these processes. Our study provided strong indication for a positive biodiversity-ecosystem functioning relationship with reduced drought stress at higher plant diversity. However, it also underlined a negative reinforcing situation: as land-use intensification decreases plant diversity in grasslands, this might subsequently increases drought sensitivity. Vice-versa, enhancing plant diversity in species-poor agricultural grasslands may moderate negative effects of future climate change.

  11. DUSCOBS - a depleted-uranium silicate backfill for transport, storage, and disposal of spent nuclear fuel

    SciTech Connect

    Forsberg, C.W.; Pope, R.B.; Ashline, R.C.; DeHart, M.D.; Childs, K.W.; Tang, J.S.

    1995-11-30

    A Depleted Uranium Silicate COntainer Backfill System (DUSCOBS) is proposed that would use small, isotopically-depleted uranium silicate glass beads as a backfill material inside storage, transport, and repository waste packages containing spent nuclear fuel (SNF). The uranium silicate glass beads would fill all void space inside the package including the coolant channels inside SNF assemblies. Based on preliminary analysis, the following benefits have been identified. DUSCOBS improves repository waste package performance by three mechanisms. First, it reduces the radionuclide releases from SNF when water enters the waste package by creating a local uranium silicate saturated groundwater environment that suppresses (1) the dissolution and/or transformation of uranium dioxide fuel pellets and, hence, (2) the release of radionuclides incorporated into the SNF pellets. Second, the potential for long-term nuclear criticality is reduced by isotopic exchange of enriched uranium in SNF with the depleted uranium (DU) in the glass. Third, the backfill reduces radiation interactions between SNF and the local environment (package and local geology) and thus reduces generation of hydrogen, acids, and other chemicals that degrade the waste package system. In addition, the DUSCOBS improves the integrity of the package by acting as a packing material and ensures criticality control for the package during SNF storage and transport. Finally, DUSCOBS provides a potential method to dispose of significant quantities of excess DU from uranium enrichment plants at potential economic savings. DUSCOBS is a new concept. Consequently, the concept has not been optimized or demonstrated in laboratory experiments.

  12. Real-time PCR quantification of the plant growth promoting bacteria Herbaspirillum seropedicae strain SmR1 in maize roots.

    PubMed

    Pereira, Tomás Pellizzaro; do Amaral, Fernanda Plucani; Dall'Asta, Pamela; Brod, Fábio Cristiano Angonesi; Arisi, Ana Carolina Maisonnave

    2014-07-01

    The plant growth promoting bacteria Herbaspirillum seropedicae SmR1 is an endophytic diazotroph found in several economically important crops. Considering that methods to monitor the plant-bacteria interaction are required, our objective was to develop a real-time PCR method for quantification of PGPB H. seropedicae in the rhizosphere of maize seedlings. Primer pairs were designed, and their specificity was verified using DNA from 12 different bacterial species. Ten standard curves of qPCR assay using HERBAS1 primers and tenfold serial dilutions of H. seropedicae SmR1 DNA were performed, and PCR efficiency of 91 % and correlation coefficient of 0.99 were obtained. H. seropedicae SmR1 limit of detection was 10(1) copies (corresponding to 60.3 fg of bacterial DNA). qPCR assay using HERBAS1 was used to detect and quantify H. seropedicae strain SmR1 in inoculated maize roots, cultivated in vitro and in pots, harvested 1, 4, 7, and 10 days after inoculation. The estimated bacterial DNA copy number per gram of root was in the range 10(7)-10(9) for plants grown in vitro and it was around 10(6) for plants grown in pots. Primer pair HERBAS1 was able to quantify H. seropedicae SmR1, and this assay can be useful for monitoring plant-bacteria interaction.

  13. On the mechanism of uranium binding to cell wall of Chara fragilis.

    PubMed

    Daković, Marko; Kovacević, Maja; Andjus, Pavle R; Bacić, Goran

    2008-09-01

    Biosorption of uranium from nuclear waste liquids and contaminated surface waters and soils has recently attracted special interest. However, the detailed mechanism of uranium uptake by plants is not well understood. The aim of this work is to investigate the role of cell wall components of the freshwater alga Chara fragilis in uranium sequestration from its solution. Three types of algae preparations: extract of cell wall polysaccharides, dried and live algae were subjected to uranium solutions of different concentration and pH. FTIR and X-ray diffraction were used to assess both potential binding sites and the form of the uranyl sequestered by algae. Sorption of uranium by live and dry algae shows remarkable differences both in terms of overall uptake and mechanisms involved. All experiments are consistent with the conclusion that coprecipitation of uranyl species with CaCO3 is the major binding mechanism in uranium sequestration by Chara fragilis, while the direct exchange of Ca2+ with UO22+ has a minor role. Live algae are twice as efficient in sequestering uranium from solution than dried ones due to the formation of different crystalline forms such as aragonite and rutherfordine forming in live algae in the presence of the uranyl species in solution. It therefore appears that metabolic processes such as photosynthesis, most likely through the regulation of pH, play a key role in the uranium uptake by plants. Further understanding of the complex mechanism of metabolic control of the uranium uptake by plants is needed before the planning of bioremediation of this element.

  14. Idaho National Engineering and Environmental Laboratory Site Report on the Production and Use of Recycled Uranium

    SciTech Connect

    L. C. Lewis; D. C. Barg; C. L. Bendixsen; J. P. Henscheid; D. R. Wenzel; B. L. Denning

    2000-09-01

    Recent allegations regarding radiation exposure to radionuclides present in recycled uranium sent to the gaseous diffusion plants prompted the Department of Energy to undertake a system-wide study of recycled uranium. Of particular interest, were the flowpaths from site to site operations and facilities in which exposure to plutonium, neptunium and technetium could occur, and to the workers that could receive a significant radiation dose from handling recycled uranium. The Idaho National Engineering and Environmental Laboratory site report is primarily concerned with two locations. Recycled uranium was produced at the Idaho Chemical Processing Plant where highly enriched uranium was recovered from spent fuel. The other facility is the Specific Manufacturing Facility (SMC) where recycled, depleted uranium is manufactured into shapes for use by their customer. The SMC is a manufacturing facility that uses depleted uranium metal as a raw material that is then rolled and cut into shapes. There are no chemical processes that might concentrate any of the radioactive contaminant species. Recyclable depleted uranium from the SMC facility is sent to a private metallurgical facility for recasting. Analyses on the recast billets indicate that there is no change in the concentrations of transuranics as a result of the recasting process. The Idaho Chemical Processing Plant was built to recover high-enriched uranium from spent nuclear fuel from test reactors. The facility processed diverse types of fuel which required uniquely different fuel dissolution processes. The dissolved fuel was passed through three cycles of solvent extraction which resulted in a concentrated uranyl nitrate product. For the first half of the operating period, the uranium was shipped as the concentrated solution. For the second half of the operating period the uranium solution was thermally converted to granular, uranium trioxide solids. The dose reconstruction project has evaluated work exposure and

  15. Uranium hexafluoride bibliography

    SciTech Connect

    Burnham, S.L.

    1988-01-01

    This bibliography is a compilation of reports written about the transportation, handling, safety, and processing of uranium hexafluoride. An on-line literature search was executed using the DOE Energy files and the Nuclear Science Abstracts file to identify pertinent reports. The DOE Energy files contain unclassified information that is processed at the Office of Scientific and Technical Information of the US Department of Energy. The reports selected from these files were published between 1974 and 1983. Nuclear Science Abstracts contains unclassified international nuclear science and technology literature published from 1948 to 1976. In addition, scientific and technical reports published by the US Atomic Energy Commission and the US Energy Research and Development Administration, as well as those published by other agencies, universities, and industrial and research organizations, are included in the Nuclear Science Abstracts file. An alphabetical listing of the acronyms used to denote the corporate sponsors follows the bibliography.

  16. URANIUM PURIFICATION PROCESS

    DOEpatents

    Ruhoff, J.R.; Winters, C.E.

    1957-11-12

    A process is described for the purification of uranyl nitrate by an extraction process. A solution is formed consisting of uranyl nitrate, together with the associated impurities arising from the HNO/sub 3/ leaching of the ore, in an organic solvent such as ether. If this were back extracted with water to remove the impurities, large quantities of uranyl nitrate will also be extracted and lost. To prevent this, the impure organic solution is extracted with small amounts of saturated aqueous solutions of uranyl nitrate thereby effectively accomplishing the removal of impurities while not allowing any further extraction of the uranyl nitrate from the organic solvent. After the impurities have been removed, the uranium values are extracted with large quantities of water.

  17. How far are we from closing the loop of sewage resource recovery? A real picture of municipal wastewater treatment plants in Italy.

    PubMed

    Papa, Matteo; Foladori, Paola; Guglielmi, Lorena; Bertanza, Giorgio

    2017-08-01

    This paper presents the results of a broad-scale survey of resource recovery implementation in Italian wastewater treatment plants (WWTPs). To the best of our knowledge, this is the first survey comprising a large number of WWTPs done in Europe: more than 600 plants were investigated, representing a treated load of around 20 million population equivalent (≈25% of the total in Italy). Conventional and innovative options for both material and energy recovery along the water and sludge line were surveyed, in order to i) offer a real and complete picture of the current state of resource recovery in WWTPs, and ii) underline key aspects and potential areas for improvements, as a baseline for future developments in the direction of more sustainable plants. Survey outcomes showed that resource recovery is just in its infancy in sewage treatment: only 40% of plants perform at least one option for material/energy recovery. The action most often implemented is recovery of material from surplus sludge for agricultural purposes and the internal reuse of treated effluent as water for various types of plant maintenance. The production of energy from biogas also occurs frequently but only in large plants. On the other hand, some well-known options, such as external reuse of treated effluent or nutrients recovery, were implemented only in a minority of plants: this is likely due to limitations resulting either from strict regulation or difficulty placing recovered products on the market. In conclusion, an overall explanation of these driving forces within the system is explored. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Arbuscular mycorrhizas contribute to phytostabilization of uranium in uranium mining tailings.

    PubMed

    Chen, Baodong; Roos, Per; Zhu, Yong-Guan; Jakobsen, Iver

    2008-05-01

    Uranium (U) tailings pose environmental risks and call for proper remediation. In this paper medic and ryegrass plants were used as host plants to examine whether inoculation with an AM fungus, Glomus intraradices, would help phytostabilization of U tailings. The need of amending with uncontaminated soil for supporting plant survival was also examined by mixing soil with U tailing at different mixing ratios. Soil amendment increased plant growth and P uptake. Ryegrass produced a more extensive root system and a greater biomass than medic plants at all mixing ratios. Medic roots were extensively colonized by G. intraradices whereas ryegrass were more sparsely colonized. Plant growth was not improved by mycorrhizas, which, however, improved P nutrition of medic plants. Medic plants contained higher U concentrations and showed higher specific U uptake efficiency compared to ryegrass. In the presence of U tailing, most U had been retained in plant roots, and this distribution pattern was further enhanced by mycorrhizal colonization. The results suggest a role for AM fungi in phytostabilization of U tailings.

  19. Evolution of uranium and thorium minerals

    NASA Astrophysics Data System (ADS)

    Hazen, R. M.; Ewing, R. C.; Sverjensky, D. A.

    2009-12-01

    The origins and near-surface distributions of the approximately 250 known uranium and/or thorium minerals elucidate principles of mineral evolution. This history can be divided into four phases. The first, from ~4.5 to 3.5 Ga, involved successive concentrations of uranium and thorium from their initial uniform trace distribution into magmatic-related fluids from which the first U4+ and Th4+ minerals, uraninite (UO2), thorianite (ThO2) and coffinite (USiO4), precipitated in the crust. The second period, from ~3.5 to 2.2 Ga, saw the formation of large low-grade concentrations of detrital uraninite (containing several weight percent Th) in the Witwatersrand-type quartz-pebble conglomerates deposited in a highly anoxic fluvial environment. Abiotic alteration of uraninite and coffinite, including radiolysis and auto-oxidation caused by radioactive decay and the formation of helium from alpha particles, may have resulted in the formation of a limited suite of uranyl oxide-hydroxides. Earth’s third phase of uranium mineral evolution, during which most known U minerals first precipitated from reactions of soluble uranyl (U6+O2)2+ complexes, followed the Great Oxidation Event (GOE) at ~2.2 Ga and thus was mediated indirectly by biologic activity. Most uraninite deposited during this phase was low in Th and precipitated from saline and oxidizing hydrothermal solutions (100 to 300°C) transporting (UO2)2+-chloride complexes. Examples include the unconformity- and vein-type U deposits (Australia and Canada) and the unique Oklo natural nuclear reactors in Gabon. The onset of hydrothermal transport of (UO2)2+ complexes in the upper crust may reflect the availability of CaSO4-bearing evaporites after the GOE. During this phase, most uranyl minerals would have been able to form in the O2-bearing near-surface environment for the first time through weathering processes. The fourth phase of uranium mineralization began approximately 400 million years ago, as the rise of land plants

  20. Retention of uranium in the chest: implications of findings in vivo and postmortem

    SciTech Connect

    Keane, A.T.; Polednak, A.P.

    1981-01-01

    An unusually protracted retention of uranium in the chests of certain workers at a uranium-processing plant has been reported in the literature. This finding has implications for the protection of current uranium workers and for health-effects studies of early workers. It is shown that the limited data obtained postmortem that have been reported do not reveal a significant unusually protracted retention of uranium in the pulmonary region or in the tracheobronchial lymph nodes. Probable explanations of the disparate findings are discussed. Data are presented on mortality from cancers of lymphatic tissues among males who worked in the period from 1943 to 1947 at the Y-12 Plant, Tennessee-Eastman Corp., Oak Ridge. No increased mortality from these cancers was evident.