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Sample records for kontrolya nakoplenij pu

  1. Anaerobic Biotransformation and Mobility of Pu and Pu-EDTA

    International Nuclear Information System (INIS)

    Bolton, H. Jr.; Rai, D.; Xun, L.

    2005-01-01

    The complexation of radionuclides (e.g., plutonium (Pu) and 60 Co) by codisposed ethylenediaminetetraacetate (EDTA) has enhanced their transport in sediments at DOE sites. Our previous NABIR research investigated the aerobic biodegradation and biogeochemistry of Pu(IV)-EDTA. Plutonium(IV) forms stable complexes with EDTA under aerobic conditions and an aerobic EDTA degrading bacterium can degrade EDTA in the presence of Pu and decrease Pu mobility. However, our recent studies indicate that while Pu(IV)-EDTA is stable in simple aqueous systems, it is not stable in the presence of relatively soluble Fe(III) compounds (i.e., Fe(OH) 3 (s)--2-line ferrihydrite). Since most DOE sites have Fe(III) containing sediments, Pu(IV) in likely not the mobile form of Pu-EDTA in groundwater. The only other Pu-EDTA complex stable in groundwater relevant to DOE sites would be Pu(III)-EDTA, which only forms under anaerobic conditions. Research is therefore needed in this brand new project to investigate the biotransformation of Pu and Pu-EDTA under anaerobic conditions. The biotransformation of Pu and Pu-EDTA under various anaerobic regimes is poorly understood including the reduction kinetics of Pu(IV) to Pu(III) from soluble (Pu(IV)-EDTA) and insoluble Pu(IV) as PuO2(am) by metal reducing bacteria, the redox conditions required for this reduction, the strength of the Pu(III)-EDTA complex, how the Pu(III)-EDTA complex competes with other dominant anoxic soluble metals (e.g., Fe(II)), and the oxidation kinetics of Pu(III)-EDTA. Finally, the formation of a stable soluble Pu(III)-EDTA complex under anaerobic conditions would require degradation of the EDTA complex to limit Pu(III) transport in geologic environments. Anaerobic EDTA degrading microorganisms have not been isolated. These knowledge gaps preclude the development of a mechanistic understanding of how anaerobic conditions will influence Pu and Pu-EDTA fate and transport to assess, model, and design approaches to stop Pu

  2. Pu-239 and Pu-240 inventories and Pu-240/ Pu-239 atom ratios in the water column off Sanriku, Japan.

    Science.gov (United States)

    Yamada, Masatoshi; Zheng, Jian; Aono, Tatsuo

    2013-04-01

    A magnitude 9.0 earthquake and subsequent tsunami occurred in the Pacific Ocean off northern Honshu, Japan, on 11 March 2011 which caused severe damage to the Fukushima Dai-ichi Nuclear Power Plant. This accident has resulted in a substantial release of radioactive materials to the atmosphere and ocean, and has caused extensive contamination of the environment. However, no information is available on the amounts of radionuclides such as Pu isotopes released into the ocean at this time. Investigating the background baseline concentration and atom ratio of Pu isotopes in seawater is important for assessment of the possible contamination in the marine environment. Pu-239 (half-life: 24,100 years), Pu-240 (half-life: 6,560 years) and Pu-241 (half-life: 14.325 years) mainly have been released into the environment as the result of atmospheric nuclear weapons testing. The atom ratio of Pu-240/Pu-239 is a powerful fingerprint to identify the sources of Pu in the ocean. The Pu-239 and Pu-240 inventories and Pu-240/Pu-239 atom ratios in seawater samples collected in the western North Pacific off Sanriku before the accident at Fukushima Dai-ichi Nuclear Power Plant will provide useful background baseline data for understanding the process controlling Pu transport and for distinguishing additional Pu sources. Seawater samples were collected with acoustically triggered quadruple PVC sampling bottles during the KH-98-3 cruise of the R/V Hakuho-Maru. The Pu-240/Pu-239 atom ratios were measured with a double-focusing SF-ICP-MS, which was equipped with a guard electrode to eliminate secondary discharge in the plasma and to enhance overall sensitivity. The Pu-239 and Pu-240 concentrations were 2.07 and 1.67 mBq/m3 in the surface water, respectively, and increased with depth; a subsurface maximum was identified at 750 m depth, and the concentrations decreased with depth, then increased at the bottom layer. The total Pu-239+240 inventory in the entire water column (depth interval 0

  3. Comparison of U-Pu-Mo, U-Pu-Nb, U-Pu-Ti and U-Pu-Zr alloys; Comparaison des alliages U-Pu-Mo, U-Pu-Nb, U-Pu-Ti, U-Pu-Zr

    Energy Technology Data Exchange (ETDEWEB)

    Boucher, R; Barthelemy, P [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-07-01

    The data concerning the U-Pu, U-Pu-Mo and U-Pu-Nb are recalled. The results obtained with U-Pu-Ti and U-Pu-Zr alloys containing 15-20 per cent Pu and 10 wt. per cent ternary element are reported. The transformation temperatures, the expansion coefficients, the nature of phases, the thermal cycling behaviour have been determined. A list of the principal properties of these different alloys is presented and the possibilities of their use as fast reactor's fuel element are considered. The U-Pu-Ti alloys seem to be quite promising: easiness of fabrication, large thermal stability, excellent behaviour in air, small quantity of zeta phase, temperature of solidus superior to 1100 deg. C. (authors) [French] On rappelle brievement les connaissances acquises sur les alliages U-Pu, U-Pu-Mo et U-Pu-Nb. On presente les resultats obtenus avec les alliages U-Pu-Ti et U-Pu-Zr pour des teneurs de 15 a 20 pour cent de plutonium et 10 pour cent en poids d'element ternaire. On a determine les temperatures de transformation, les coefficients de dilatation, la nature des phases, la conductibilite thermique a 20 deg. C, la tenue au cyclage thermique et diverses autres proprietes. Un tableau resume les principales proprietes des divers alliages. On considere les possibilites d'emploi de ces alliages comme combustibles de reacteur rapide. Les alliages U-Pu-Ti paraissent particulierement interessants: facilite d'elaboration, stabilite thermique etendue, tenue dans l'air excellente, faible quantite de la phase U-Pu zeta, temperature de fusion commencante superieure a 1100 deg. C. (auteurs)

  4. Comparison of U-Pu-Mo, U-Pu-Nb, U-Pu-Ti and U-Pu-Zr alloys

    International Nuclear Information System (INIS)

    Boucher, R.; Barthelemy, P.

    1964-01-01

    The data concerning the U-Pu, U-Pu-Mo and U-Pu-Nb are recalled. The results obtained with U-Pu-Ti and U-Pu-Zr alloys containing 15-20 per cent Pu and 10 wt. per cent ternary element are reported. The transformation temperatures, the expansion coefficients, the nature of phases, the thermal cycling behaviour have been determined. A list of the principal properties of these different alloys is presented and the possibilities of their use as fast reactor's fuel element are considered. The U-Pu-Ti alloys seem to be quite promising: easiness of fabrication, large thermal stability, excellent behaviour in air, small quantity of zeta phase, temperature of solidus superior to 1100 deg. C. (authors) [fr

  5. Two 238Pu inhalation incidents

    International Nuclear Information System (INIS)

    Fleming, R.R.; Hall, R.M.

    1978-06-01

    Two employees inhaled significant amounts of 238 Pu in separate unrelated contamination incidents in 1977. Both acute exposure incidents are described and the urine, feces, and in-vivo chest count data for each employee. Case B ( 238 PuNO 3 ) received 24 DTPA treatments beginning the day of the incident while, for medical reasons, Case A ( 238 PuO 2 ) received no therapy

  6. Biodegradation of PuEDTA and Impacts on Pu Mobility

    International Nuclear Information System (INIS)

    Bolton, H. Jr.; Rai, D.; Xun, L.

    2004-01-01

    The contamination of many DOE sites by Pu presents a long-term problem because of its long half-life (240,000 yrs) and the low drinking water standard ( -12 M). EDTA was co-disposed with radionuclides (e.g., Pu, 60 Co), formed strong complexes, and enhanced radionuclide transport at several DOE sites. Biodegradation of EDTA should decrease Pu mobility. One objective of this project was to determine the biodegradation of EDTA in the presence of PuEDTA complexes. The aqueous system investigated at pH 7 (10 -4 M EDTA and 10 -6 M Pu) contained predominantly Pu(OH) 2 EDTA 2- . The EDTA was degraded at a faster rate in the presence of Pu. As the total concentration of both EDTA and PuEDTA decreased (i.e., 10 -5 M EDTA and 10 -7 M PuEDTA), the presence of Pu decreased the biodegradation rate of the EDTA. It is currently unclear why the concentration of Pu directly affects the increase/decrease in rate of EDTA biodegradation. The soluble Pu concentration decreased, in agreement with thermodynamic predictions, as the EDTA was biodegraded, indicating that biodegradation of EDTA will decrease Pu mobility when the Pu is initially present as Pu(IV)EDTA. A second objective was to investigate how the presence of competing metals, commonly encountered in geologic media, will influence the speciation and biodegradation of Pu(IV)-EDTA. Studies on the solubilities of Fe(OH) 3 (s) and of Fe(OH) 3 (s) plus PuO 2 (am) in the presence of EDTA and as a function of pH showed that Fe(III) out competes the Pu(IV) for the EDTA complex, thereby showing that Pu(IV) will not form stable complexes with EDTA for enhanced transport of Pu in Fe(III) dominated subsurface systems. A third objective is to investigate the genes and enzymes involved in EDTA biodegradation. BNC1 can use EDTA and another synthetic chelating agent nitrilotriacetate (NTA) as sole carbon and nitrogen sources. The same catabolic enzymes are responsible for both EDTA and NTA degradation except that additional enzymes are

  7. Designing Pu600 for Authentication

    International Nuclear Information System (INIS)

    White, G.

    2008-01-01

    Many recent Non-proliferation and Arms Control software projects include an authentication component. Demonstrating assurance that software and hardware performs as expected without hidden 'back-doors' is crucial to a project's success. In this context, 'authentication' is defined as determining that the system performs only its intended purpose and performs that purpose correctly and reliably over many years. Pu600 is a mature software solution for determining the presence of Pu and the ratio of Pu240 to Pu239 by analyzing the gamma ray spectra in the 600 KeV region. The project's goals are to explore hardware and software technologies which can by applied to Pu600 which ease the authentication of a complete, end-to-end solution. We will discuss alternatives and give the current status of our work

  8. Designing Pu600 for Authentication

    Energy Technology Data Exchange (ETDEWEB)

    White, G

    2008-07-10

    Many recent Non-proliferation and Arms Control software projects include an authentication component. Demonstrating assurance that software and hardware performs as expected without hidden 'back-doors' is crucial to a project's success. In this context, 'authentication' is defined as determining that the system performs only its intended purpose and performs that purpose correctly and reliably over many years. Pu600 is a mature software solution for determining the presence of Pu and the ratio of Pu240 to Pu239 by analyzing the gamma ray spectra in the 600 KeV region. The project's goals are to explore hardware and software technologies which can by applied to Pu600 which ease the authentication of a complete, end-to-end solution. We will discuss alternatives and give the current status of our work.

  9. Evaluation of nuclear data of 244Pu and 237Pu

    International Nuclear Information System (INIS)

    Nakagawa, Tsuneo; Konshin, V.A.

    1995-10-01

    The evaluation of nuclear data for 244 Pu and 237 Pu was made in the neutron energy region from 10 -5 eV to 20 MeV. For the both nuclides, the total, elastic and inelastic scattering, fission, capture, (n,2n) and (n,3n) reaction cross sections were evaluated on the basis of theoretical calculation. The resonance parameters were given for 244 Pu. The angular and energy distributions of secondary neutrons were also estimated for the both nuclides. The results were compiled in the ENDF-5 format and will be adopted in JENDL Actinoid File. (author)

  10. Status of 239Pu evaluations

    International Nuclear Information System (INIS)

    Kawano, Toshihiko; Talou, Patrick; Chadwick, Mark B.

    2014-01-01

    This paper summarises the current status of nuclear data evaluations for n+ 239 Pu. The nuclear data we address include fission, capture, scattering cross-sections, as well as the prompt fission neutron energy spectrum, which has large sensitivities to the criticality benchmark testing. The evaluated nuclear data files currently available for 239 Pu are compared, and the source of differences in the cross-sections are discussed. Some open questions on the statistical model calculations for deformed systems are also given. (authors)

  11. PU-ICE Summary Information.

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-05-01

    The Generator Knowledge Report for the Plutonium Isentropic Compression Experiment Containment Systems (GK Report) provides information for the Plutonium Isentropic Compression Experiment (Pu- ICE) program to support waste management and characterization efforts. Attachment 3-18 presents generator knowledge (GK) information specific to the eighteenth Pu-ICE conducted in August 2015, also known as ‘Shot 18 (Aug 2015) and Pu-ICE Z-2841 (1).’ Shot 18 (Aug 2015) was generated on August 28, 2015 (1). Calculations based on the isotopic content of Shot 18 (Aug 2015) and the measured mass of the containment system demonstrate the post-shot containment system is low-level waste (LLW). Therefore, this containment system will be managed at Sandia National Laboratory/New Mexico (SNL/NM) as LLW. Attachment 3-18 provides documentation of the TRU concentration and documents the concentration of any hazardous constituents.

  12. 11-year field study of Pu migration from Pu III, IV, and VI sources

    International Nuclear Information System (INIS)

    Kaplan, D.I.; Serkiz, S.M.; Demirkanli, D.I.; Gumapas, L.; Fjeld, R.A.; Molz, F.J.; Powell, B.A.

    2005-01-01

    Full text of publication follows: Understanding the processes controlling Pu mobility in the subsurface environment is important for estimating the amount of Pu waste that can be safely disposed in vadose zone burial sites. To study long-term Pu mobility, four 52-L lysimeters filled with sediment collected from the Savannah River Site near Aiken South Carolina were amended with well characterized solid Pu sources (Pu III Cl 3 , Pu IV (NO 3 ) 4 , Pu IV (C 2 O 4 ) 2 , and Pu VI O 2 (NO 3 ) 2 ) and left exposed to natural precipitation for 2 to 11 years. Pu oxidation state distribution in the Pu(III) and Pu(IV) lysimeters sediments (a red clayey sediment, pH = 6.3) were similar, consisting of 0% Pu(III), >92% Pu(IV), 1% Pu(V), 1% Pu(VI), and the remainder was a Pu polymer. These three lysimeters also had near identical sediment Pu concentration profiles, where >95% of the Pu remained within 1.25 cm of the source after 11 years; moving at an overall rate of 0.9 cm yr -1 . As expected, Pu moved more rapidly through the Pu(VI) lysimeter, at an overall rate of 12.5 cm yr -1 . Solute transport modeling of the sediment Pu concentration profile data in the Pu(VI) lysimeter indicated that some transformation of Pu into a much less mobile form, presumably Pu(IV), had occurred during the course of the two year study. This modeling also supported previous laboratory measurements showing that Pu(V) or Pu(VI) reduction was five orders of magnitude faster than corresponding Pu(III) or Pu(IV) oxidation. The slow oxidation rate (1 x 10-8 hr -1 ; t 1/2 = 8,000 yr) was not discernable from the Pu(VI) lysimeter data that reflected only two years of transport but was readily discernable from the Pu(III) and Pu(IV) lysimeter data that reflected 11 yr of transport. (authors)

  13. Determination of plutonium isotopes (238Pu, 239Pu, 240Pu, 241Pu) in environmental samples using radiochemical separation combined with radiometric and mass spectrometric measurements.

    Science.gov (United States)

    Xu, Yihong; Qiao, Jixin; Hou, Xiaolin; Pan, Shaoming; Roos, Per

    2014-02-01

    This paper reports an analytical method for the determination of plutonium isotopes ((238)Pu, (239)Pu, (240)Pu, (241)Pu) in environmental samples using anion exchange chromatography in combination with extraction chromatography for chemical separation of Pu. Both radiometric methods (liquid scintillation counting and alpha spectrometry) and inductively coupled plasma mass spectrometry (ICP-MS) were applied for the measurement of plutonium isotopes. The decontamination factors for uranium were significantly improved up to 7.5 × 10(5) for 20 g soil compared to the level reported in the literature, this is critical for the measurement of plutonium isotopes using mass spectrometric technique. Although the chemical yield of Pu in the entire procedure is about 55%, the analytical results of IAEA soil 6 and IAEA-367 in this work are in a good agreement with the values reported in the literature or reference values, revealing that the developed method for plutonium determination in environmental samples is reliable. The measurement results of (239+240)Pu by alpha spectrometry agreed very well with the sum of (239)Pu and (240)Pu measured by ICP-MS. ICP-MS can not only measure (239)Pu and (240)Pu separately but also (241)Pu. However, it is impossible to measure (238)Pu using ICP-MS in environmental samples even a decontamination factor as high as 10(6) for uranium was obtained by chemical separation. © 2013 Elsevier B.V. All rights reserved.

  14. Early retention of 237Pu + 239Pu in mature beagles

    International Nuclear Information System (INIS)

    Lloyd, R.D.; McFarland, S.S.; Atherton, D.R.; Bruenger, F.W.; Taylor, G.N.; Mays, C.W.

    1978-01-01

    Five mature beagles, ranging in age from 57 to 84 months, were injected intravenously with about 0.05-0.1 μCi/kg of 239 Pu(IV) citrate to which tracer amounts of the photon-emitter 237 Pu had been added. Plutonium retention in liver and in non-liver tissue (mainly skeleton) was measured periodically in the living dogs for nearly 4 months after injection by a combination of total-body and partial-body counting. All excreta were collected during the first 21 days and analysed for their Pu content. One dog was sacrificed at 14 days and another at 118 days for distribution studies. About 17% (14-20%) of the injected Pu was excreted in the urine and feces in the first 3 weeks, about the same as that excreted in a corresponding time by beagles injected as young adults (14%), but substantially more than beagles injected as juveniles (11%). In contrasts to juvenile beagles injected at 3 months of age, in which early retention was about 12% in liver and 68% in the skeleton, mature beagles retained about 30% in liver and 50% in the skeleton. Retention in young adult beagles injected at 17 months of age was similar to that of mature dogs. Relative distribution of skeletal plutonium among various bones was similar in the mature animals to that seen previously in young adults, but quite different from that of juveniles. A notable exception was the humerus for which there was no significant difference (P>0.2) in the % of retained skeletal Pu represented by the humerus among the juvenile, young adult and mature dogs. (author)

  15. Direct spectrophotometric analysis of low level Pu (III) in Pu(IV) nitrate solution

    International Nuclear Information System (INIS)

    Mageswaran, P.; Suresh Kumar, K.; Kumar, T.; Gayen, J.K.; Shreekumar, B.; Dey, P.K.

    2010-01-01

    Among the various methods demonstrated for the conversion of plutonium nitrate to its oxide, the oxalate precipitation process either as Pu (III) or Pu (IV) oxalate gained wide acceptance. Since uranous nitrate is the most successful partitioning agent used in the PUREX process for the separation of Pu from the bulk amount of U, the Pu (III) oxalate precipitation of the purified nitrate solution will not give required decontamination from U. Hence Pu IV oxalate precipitation process is a better option to achieve the end user's specified PuO 2 product. Prior to the precipitation process, ensuring of the Pu (IV) oxidation state is essential. Hence monitoring of the level of Pu oxidation state either Pu (III) or Pu (IV) in the feed solution plays a significant role to establish complete conversion of Pu (III). The method in vogue to estimate Pu(lV) content is extractive radiometry using Theonyl Trifluoro Acetone (TTA). As the the method warrants a sample preparation with respect to acidity, a precise measurement of Pu (IV) without affecting the Pu(III) level in the feed sample is difficult. Present study is focused on the exploration of direct spectrophotometry using an optic fiber probe of path length of 40mm to monitor the low level of Pu(III) after removing the bulk Pu(lV) which interfere in the Pu(III) absorption spectrum, using TTA-TBP synergistic mixture without changing the sample acidity

  16. Use of 236Pu and 242Pu as a radiochemical tracer for estimation of Pu in bioassay samples by fission track analysis

    International Nuclear Information System (INIS)

    Sawant, Pramilla D.; Prabhu, Supreetha P.; Kalsi, P.C.

    2008-01-01

    236 Pu and 242 Pu are routinely used as radiochemical yield monitors in India for bioassay monitoring of occupational workers by alpha spectrometry. Fission Track Analysis (FTA) is also being standardized for trace level determination of Pu in bioassay samples. The present study, reports the utility of 236 Pu and 242 Pu as radiochemical tracers in estimation of Pu in bioassay samples by FTA technique. The advantages of using 236 Pu tracer in FTA over 242 Pu as well as the interference caused due to presence of 241 Pu in the bioassay samples of occupational workers handling power reactor grade Pu is discussed. (author)

  17. Economical Production of Pu-238

    Energy Technology Data Exchange (ETDEWEB)

    Steven D. Howe; Douglas Crawford; Jorge Navarro; Terry Ring

    2013-02-01

    All space exploration missions traveling beyond Jupiter must use radioisotopic power sources for electrical power. The best isotope to power these sources is plutonium-238. The US supply of Pu-238 is almost exhausted and will be gone within the next decade. The Department of Energy has initiated a production program with a $10M allocation from NASA but the cost is estimated at over $100 M to get to production levels. The Center for Space Nuclear Research has conceived of a potentially better process to produce Pu-238 earlier and for significantly less cost. The new process will also produce dramatically less waste. Potentially, the front end costs could be provided by private industry such that the government only had to pay for the product produced. Under a NASA Phase I NIAC grant, the CSNR has evaluated the feasibility of using a low power, commercially available nuclear reactor to produce at least 1.5 kg of Pu-238 per year. The impact on the neutronics of the reactor have been assessed, the amount of Neptunium target material estimated, and the production rates calculated. In addition, the size of the post-irradiation processing facility has been established. In addition, a new method for fabricating the Pu-238 product into the form used for power sources has been identified to reduce the cost of the final product. In short, the concept appears to be viable, can produce the amount of Pu-238 needed to support the NASA missions, can be available within a few years, and will cost significantly less than the current DOE program.

  18. Migration of plutonium from freshwater ecosystem at Hanford. [/sup 238/Pu, /sup 239/Pu, /sup 240/Pu

    Energy Technology Data Exchange (ETDEWEB)

    Emery, R. M.; Klopfer, D. C.; McShane, M. C.

    1977-09-01

    A reprocessing waste pond at Hanford has been inventoried to determine quantities of plutonium (Pu) that have been accumulated since its formation in 1944. Expressions of export were developed from these inventory data and from informed assumptions about the vectors which act to mobilize material containing Pu. This 14-acre pond provides a realistic illustration of the mobility of Pu in a lentic ecosystem. The ecological behavior of Pu in this pond is similar to that in other contaminated aquatic systems having widely differing limnological characteristics. Since its creation, this pond has received about one Ci of /sup 239/,/sup 240/Pu and /sup 238/Pu, most of which has been retained by its sediments. Submerged plants, mainly diatoms and Potamogeton, accumulate >95% of the Pu contained in biota. Emergent insects are the only direct biological route of export, mobilizing about 5 x 10/sup 3/ nCi of Pu annually, which is also the estimated maximum quantity of the Pu exported by waterfowl, birds and mammals collectively. There is no apparent significant export by wind, and it is not likely that Pu has migrated to the ground water below U-Pond via percolation. Although this pond has a rapid flushing rate, a eutrophic nutrient supply with a diverse biotic profile, and interacts with an active terrestrial environment, it appears to effectively bind Pu and prevent it from entering pathways to man and other life.

  19. Multi-isotopic determination of plutonium (239Pu, 240Pu, 241Pu and 242Pu) in marine sediments using sector-field inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Donard, O F X; Bruneau, F; Moldovan, M; Garraud, H; Epov, V N; Boust, D

    2007-03-28

    Among the transuranic elements present in the environment, plutonium isotopes are mainly attached to particles, and therefore they present a great interest for the study and modelling of particle transport in the marine environment. Except in the close vicinity of industrial sources, plutonium concentration in marine sediments is very low (from 10(-4) ng kg(-1) for (241)Pu to 10 ng kg(-1) for (239)Pu), and therefore the measurement of (238)Pu, (239)Pu, (240)Pu, (241)Pu and (242)Pu in sediments at such concentration level requires the use of very sensitive techniques. Moreover, sediment matrix contains huge amounts of mineral species, uranium and organic substances that must be removed before the determination of plutonium isotopes. Hence, an efficient sample preparation step is necessary prior to analysis. Within this work, a chemical procedure for the extraction, purification and pre-concentration of plutonium from marine sediments prior to sector-field inductively coupled plasma mass spectrometry (SF-ICP-MS) analysis has been optimized. The analytical method developed yields a pre-concentrated solution of plutonium from which (238)U and (241)Am have been removed, and which is suitable for the direct and simultaneous measurement of (239)Pu, (240)Pu, (241)Pu and (242)Pu by SF-ICP-MS.

  20. The radiolysis of solutions containing Pu(6)

    International Nuclear Information System (INIS)

    Rance, P.J.W.; Zilberman, B.Y.

    2000-01-01

    The reduction of Pu(VI) in nitric acid solutions containing uranium and various fission product elements as a result of both its inherent alpha radiation and also external gamma irradiation at dose rates similar to those experienced by dissolved fuel solutions has been investigated. The presence of the additional metals has been shown to eliminate the induction periods required prior to the reduction of Pu(VI) in nitric acid. G values for the auto-radiolytic reduction of Pu(VI) have been found to be between 0.6 and 1.1 for 3 g/1 Pu solutions containing between 0.12 and 9.2 % 238 Pu (balance 239 Pu). Uranium and palladium have been found to accelerate the reduction of Pu(VI) during gamma irradiation at dose rates of between 0.41 and 1.64 kGy/hour. (authors)

  1. The radiolysis of solutions containing Pu(6)

    Energy Technology Data Exchange (ETDEWEB)

    Rance, P.J.W. [BNFL British Nuclear Fuels, Sellafield, Seascale, Cumbria, Research and Technology (United Kingdom); Zilberman, B.Y. [V.G. Khlopin Radium Institute, St. Petersburg (Russian Federation)

    2000-07-01

    The reduction of Pu(VI) in nitric acid solutions containing uranium and various fission product elements as a result of both its inherent alpha radiation and also external gamma irradiation at dose rates similar to those experienced by dissolved fuel solutions has been investigated. The presence of the additional metals has been shown to eliminate the induction periods required prior to the reduction of Pu(VI) in nitric acid. G values for the auto-radiolytic reduction of Pu(VI) have been found to be between 0.6 and 1.1 for 3 g/1 Pu solutions containing between 0.12 and 9.2 % {sup 238}Pu (balance {sup 239}Pu). Uranium and palladium have been found to accelerate the reduction of Pu(VI) during gamma irradiation at dose rates of between 0.41 and 1.64 kGy/hour. (authors)

  2. Electronic Correlation Strength of Pu

    DEFF Research Database (Denmark)

    Svane, A.; C. Albers, R.; E. Christensen, N.

    2013-01-01

    A new electronic quantity, the correlation strength, is defined as a necessary step for understanding the properties and trends in strongly correlated electronic materials. As a test case, this is applied to the different phases of elemental Pu. Within the GW approximation we have surprisingly...... found a "universal" scaling relationship, where the f-electron bandwidth reduction due to correlation effects is shown to depend only upon the local density approximation (LDA) bandwidth and is otherwise independent of crystal structure and lattice constant....

  3. {sup 239}Pu and {sup 240}Pu inventories and {sup 240}Pu/{sup 239}Pu atom ratios in the equatorial Pacific Ocean water column

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Masatoshi, E-mail: myamada@cc.hirosaki-u.ac.jp [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan); Zheng, Jian [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan)

    2012-07-15

    The {sup 239+240}Pu concentrations and {sup 240}Pu/{sup 239}Pu atom ratios were determined by alpha spectrometry and inductively coupled plasma mass spectrometry for seawater samples from two stations, one at the equator and the other in the equatorial South Pacific. To better understand the fate of Pu isotopes, this study dealt with the contribution of the close-in fallout Pu from the Pacific Proving Grounds (PPG) in water columns of the Pacific Ocean. The {sup 239}Pu, {sup 240}Pu and {sup 239+240}Pu inventories over the depth interval 0-3000 m at the equator station were 10.4, 8.9 and 19.3 Bq m{sup -2}, respectively. Further, no noticeable difference was observed in {sup 239}Pu, {sup 240}Pu and {sup 239+240}Pu inventories over the depth interval 0-3000 m between the two stations. The total {sup 239+240}Pu inventories were significantly higher than the expected cumulative deposition density of global fallout. Water column {sup 239+240}Pu inventories measured in this study were lower than those reported for comparable stations in the Geochemical Ocean Sections Study, indicating that these inventories have been decreasing at average rates of 0.89 {+-} 0.07 and 0.16 {+-} 0.07 Bq m{sup -2} yr{sup -1} at the equator and equatorial South Pacific stations, respectively, from 1973 to 1990. The obtained {sup 240}Pu/{sup 239}Pu atom ratios were higher than the mean global fallout ratio of 0.18. These high atom ratios proved the existence of close-in tropospheric fallout Pu from the PPG in the Marshall Islands. The {sup 239+240}Pu inventories originating from the close-in fallout in the entire water column were estimated to be 11.1 Bq m{sup -2} at the equator station and 7.1 Bq m{sup -2} at the equatorial South Pacific Ocean station, and the relative percentages of close-in fallout Pu were 40% at the former and 34% at the latter. A significant amount of close-in fallout Pu originating from the PPG has been transported to deep layers below the 1000 m depth in the equatorial

  4. Computing and physical methods to calculate Pu

    International Nuclear Information System (INIS)

    Mohamed, Ashraf Elsayed Mohamed

    2013-01-01

    Main limitations due to the enhancement of the plutonium content are related to the coolant void effect as the spectrum becomes faster, the neutron flux in the thermal region tends towards zero and is concentrated in the region from 10 Ke to 1 MeV. Thus, all captures by 240 Pu and 242 Pu in the thermal and epithermal resonance disappear and the 240 Pu and 242 Pu contributions to the void effect became positive. The higher the Pu content and the poorer the Pu quality, the larger the void effect. The core control in nominal or transient conditions Pu enrichment leads to a decrease in (B eff.), the efficiency of soluble boron and control rods. Also, the Doppler effect tends to decrease when Pu replaces U, so, that in case of transients the core could diverge again if the control is not effective enough. As for the voiding effect, the plutonium degradation and the 240 Pu and 242 Pu accumulation after multiple recycling lead to spectrum hardening and to a decrease in control. One solution would be to use enriched boron in soluble boron and shutdown rods. In this paper, I discuss and show the advanced computing and physical methods to calculate Pu inside the nuclear reactors and glovebox and the different solutions to be used to overcome the difficulties that effect, on safety parameters and on reactor performance, and analysis the consequences of plutonium management on the whole fuel cycle like Raw materials savings, fraction of nuclear electric power involved in the Pu management. All through two types of scenario, one involving a low fraction of the nuclear park dedicated to plutonium management, the other involving a dilution of the plutonium in all the nuclear park. (author)

  5. Anthropogenic Pu distribution in Tropical East Pacific

    International Nuclear Information System (INIS)

    Kinoshita, Norikazu; Sumi, Takahiro; Takimoto, Kiyotaka; Nagaoka, Mika; Yokoyama, Akihiko; Nakanishi, Takashi

    2011-01-01

    The geographical distribution of the anthropogenic radionuclides 238 Pu and 239+240 Pu in the Tropical East Pacific in 2003 was studied from the viewpoint of material migration. We measured the contents of Pu isotopes in seawater and in sediment from the sea bottom. The distributions of Pu isotopes, together with those of coexisting nitrate and phosphate species and dissolved oxygen, are discussed in relation to the potential temperature and potential density (sigma-θ). The Pu contents in sediment samples were compared with those in the seawater. Horizontal migration across the Equator from north to south was investigated at depths down to ∼ 800 m in the eastern Pacific. The Pu distribution at 0-400 m correlated well with the distribution of potential temperature. Maximum Pu levels were observed in the subsurface layer at 600-800 m, corresponding to the depth where sigma-θ ∼ 27.0. It is suggested that the Pu distribution depends on the structure of the water mass and the particular temperature and salinity. The water column/sediment column inventory ratio and the vertical distribution of Pu may reflect the efficiency of scavenging in the relevant water areas. Research Highlights: → Geographical distributions of Pu isotopes were investigated from viewpoint of material migration. → Horizontal migration from north to south was found at depths down to ∼800 m in the eastern Pacific. → Pu distribution at 0-400 m was correlated with water temperature. → The distribution at 600-800 m correlated with water mass structure. → Pu in seawater and sediment gave information about efficiency of scavenging.

  6. Migration behaviour of Pu released from Pu-doped glass in compacted bentonite

    International Nuclear Information System (INIS)

    Ashida, T.; Kohara, Y.; Yui, M.

    1994-01-01

    In order to investigate the coupled behavior of Pu release from the waste glass and transport in bentonite, a migration experiment with compacted sodium-type bentonite saturated with distilled water was carried out at room temperature, in which Pu-doped borosilicate glass was sandwiched. Under these conditions, leaching of Pu from the glass, diffusion and sorption of Pu in the compacted bentonite occur simultaneously. (orig.)

  7. Pu Anion Exchange Process Intensification

    International Nuclear Information System (INIS)

    Taylor-Pashow, Kathryn M. L.

    2017-01-01

    This research is focused on improving the efficiency of the anion exchange process for purifying plutonium. While initially focused on plutonium, the technology could also be applied to other ion-exchange processes. Work in FY17 focused on the improvement and optimization of porous foam columns that were initially developed in FY16. These foam columns were surface functionalized with poly(4-vinylpyridine) (PVP) to provide the Pu specific anion-exchange sites. Two different polymerization methods were explored for maximizing the surface functionalization with the PVP. The open-celled polymeric foams have large open pores and large surface areas available for sorption. The fluid passes through the large open pores of this material, allowing convection to be the dominant mechanism by which mass transport takes place. These materials generally have very low densities, open-celled structures with high cell interconnectivity, small cell sizes, uniform cell size distributions, and high structural integrity. These porous foam columns provide advantages over the typical porous resin beads by eliminating the slow diffusion through resin beads, making the anion-exchange sites easily accessible on the foam surfaces. The best performing samples exceeded the Pu capacity of the commercially available resin, and also offered the advantage of sharper elution profiles, resulting in a more concentrated product, with less loss of material to the dilute heads and tails cuts. An alternate approach to improving the efficiency of this process was also explored through the development of a microchannel array system for performing the anion exchange.

  8. Pu Anion Exchange Process Intensification

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, Kathryn M. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-10-06

    This research is focused on improving the efficiency of the anion exchange process for purifying plutonium. While initially focused on plutonium, the technology could also be applied to other ion-exchange processes. Work in FY17 focused on the improvement and optimization of porous foam columns that were initially developed in FY16. These foam columns were surface functionalized with poly(4-vinylpyridine) (PVP) to provide the Pu specific anion-exchange sites. Two different polymerization methods were explored for maximizing the surface functionalization with the PVP. The open-celled polymeric foams have large open pores and large surface areas available for sorption. The fluid passes through the large open pores of this material, allowing convection to be the dominant mechanism by which mass transport takes place. These materials generally have very low densities, open-celled structures with high cell interconnectivity, small cell sizes, uniform cell size distributions, and high structural integrity. These porous foam columns provide advantages over the typical porous resin beads by eliminating the slow diffusion through resin beads, making the anion-exchange sites easily accessible on the foam surfaces. The best performing samples exceeded the Pu capacity of the commercially available resin, and also offered the advantage of sharper elution profiles, resulting in a more concentrated product, with less loss of material to the dilute heads and tails cuts. An alternate approach to improving the efficiency of this process was also explored through the development of a microchannel array system for performing the anion exchange.

  9. Biodegradation of PuEDTA and Impacts on Pu Mobility

    International Nuclear Information System (INIS)

    Xun, Luying; Bolton, Jr. Harvey

    2001-01-01

    Ethylenediaminetetraacetate (EDTA) and nitrilotriacetate (NTA) are synthetic chelating agents, which can form strong water-soluble complexes with radionuclides and metals and has been used to decontaminate and process nuclear materials. Synthetic chelating agents were co-disposed with radionuclides (e.g., 60Co, Pu) and heavy metals enhancing their transport in the subsurface. An understanding of EDTA biodegradation is essential to help mitigate enhanced radionuclide transport by EDTA. The objective of this research is to develop fundamental data on factors that govern the biodegradation of radionuclide-EDTA. These factors include the dominant EDTA aqueous species, the biodegradation of various metal-EDTA complexes, the uptake of various metal-EDTA complexes into the cell, the distribution and mobility of the radionuclide during and after EDTA biodegradation, and the enzymology and genetics of EDTA biodegradation

  10. Analysis of plutonium isotope ratios including 238Pu/239Pu in individual U-Pu mixed oxide particles by means of a combination of alpha spectrometry and ICP-MS.

    Science.gov (United States)

    Esaka, Fumitaka; Yasuda, Kenichiro; Suzuki, Daisuke; Miyamoto, Yutaka; Magara, Masaaki

    2017-04-01

    Isotope ratio analysis of individual uranium-plutonium (U-Pu) mixed oxide particles contained within environmental samples taken from nuclear facilities is proving to be increasingly important in the field of nuclear safeguards. However, isobaric interferences, such as 238 U with 238 Pu and 241 Am with 241 Pu, make it difficult to determine plutonium isotope ratios in mass spectrometric measurements. In the present study, the isotope ratios of 238 Pu/ 239 Pu, 240 Pu/ 239 Pu, 241 Pu/ 239 Pu, and 242 Pu/ 239 Pu were measured for individual Pu and U-Pu mixed oxide particles by a combination of alpha spectrometry and inductively coupled plasma mass spectrometry (ICP-MS). As a consequence, we were able to determine the 240 Pu/ 239 Pu, 241 Pu/ 239 Pu, and 242 Pu/ 239 Pu isotope ratios with ICP-MS after particle dissolution and chemical separation of plutonium with UTEVA resins. Furthermore, 238 Pu/ 239 Pu isotope ratios were able to be calculated by using both the 238 Pu/( 239 Pu+ 240 Pu) activity ratios that had been measured through alpha spectrometry and the 240 Pu/ 239 Pu isotope ratios determined through ICP-MS. Therefore, the combined use of alpha spectrometry and ICP-MS is useful in determining plutonium isotope ratios, including 238 Pu/ 239 Pu, in individual U-Pu mixed oxide particles. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Safety requirements for the Pu carriers

    International Nuclear Information System (INIS)

    Mishima, H.

    1993-01-01

    Ministry of Transport of Japan has now set about studying requirements for Pu carriers to ensure safety. It was first studied what the basic concept of safe carriage of Pu should be, and the basic ideas have been worked out. Next the requirements for the Pu carriers were studied based on the above. There are at present no international requirements of construction and equipment for the nuclear-material carriers, but MOT of Japan has so far required special construction and equipment for the nuclear-material carriers which carry a large amount of radioactive material, such as spent fuel or low level radioactive waste, corresponding to the level of the respective potential hazard. The requirements of construction and equipment of the Pu carriers have been established considering the difference in heat generation between Pu and spent fuel, physical protection, and so forth, in addition to the above basic concept. (J.P.N.)

  12. Simultaneous measurement of 239Pu, 240Pu, 241Pu, and 242Pu by high resolution inductively coupled plasma mass spectrometer (HR ICP-MS) in marine sediments

    International Nuclear Information System (INIS)

    Bruneau, F.

    1999-01-01

    Transuranics elements are of particular interest in radioecological studies because of their radiotoxicity and their potential use to decipher source fingerprints and transport processes. The simultaneous measurement of 239 Pu, 240 Pu, 241 Pu, and 242 Pu in environmental samples requires a specific chemical procedure. This work deals with an analytical procedure which yields a very high grade of purification of Pu suitable for ultra low level detection by HR ICP-MS, from marine sediments. After the elimination of major elements (Fe, Al, Mg...) by a first chromatographic separation, a new device of purification by solvent extraction and concentration by a second chromatographic separation is used to obtain a concentrated and high purified solution of plutonium. The chemical procedure have been validated on IAEA certified sediment samples and on sediment samples collected in the roads of Cherbourg which had been previously analysed by other techniques (a spectrometry and thermo-ionisation mass spectrometer). (author)

  13. Determination of {sup 240}Pu/{sup 239}Pu ratio and its significance in environmental studies

    Energy Technology Data Exchange (ETDEWEB)

    Muramatsu, Yasuyuki [National Inst. of Radiological Sciences, Chiba (Japan)

    1999-03-01

    Analytical procedures for the determination of Pu concentrations and its isotopic ratios in environmental samples were developed by using ICP-MS. Detection limit of Pu by ICP-MS was about 0.02 pg ml{sup -1} (0.05 mBq ml{sup -1} for {sup 239}Pu; 0.17 mBq ml{sup -1} for {sup 240}Pu) in the sample solution. Analytical results of {sup 239+240}Pu in IAEA standard reference materials indicated that the accuracy of this method was satisfactory. Data on the {sup 240}Pu/{sup 239}Pu atom ratios, which are rare in the literature, were also obtained for soil and sediment samples (including IAEA standard reference materials) from different areas such as Irish Sea, Mururoa Atoll, Marshall Islands, Chernobyl, Kyshtym, Nagasaki and some other places in Japan. The range of the {sup 240}Pu/{sup 239}Pu ratios was about 0.04-0.4, and the ratios are depending on the origin of the materials. Analytical results for the {sup 240}Pu/{sup 239}Pu atom ratios provide information about the source of the contamination and the transfer of plutonium in the environment. (author)

  14. Deposition of Pu-239 in human bodies

    International Nuclear Information System (INIS)

    Okabayashi, Hiroyuki

    1976-01-01

    It is known that plutonium produced by nuclear explosion tests has been widely dispersed on all over the earth and Pu-238 generated by the ''Accident of SNAP-9A'' in 1964 has been disposed into the atmosphere. These Pu are gradually falling down on the earth and taken into the human body through inhalation and ingestion. The measurements on the concentrations of Pu in bones and other various organs of Japanese population have been carried out. The results reveal that the concentrations of Pu in bones has a trend to be gradually increasing since 1962 and seems to be saturated at about 1970. The concentrations of Pu in bones sampled in 1971 are, in average, in the level of 4fCi per gram of wet samples and those in other organs (lung, liver, spleen, kidney, reproductive organs, etc.) sampled from 1963 to 1973 are in the level of 0.5-3.4 fCi per gram of wet tissues. Pu has been identified in the bones of fetus and infants and the averaged concentrations of placenta was 42.5 fCi. These may indicate that Pu would be transferred to the fetus through the placenta of mother. Some calculation has been attempted on the ratio of contributions through inhalation and ingestion to the body content of Pu, by using the formula for the scheme of metabolism of Pu compound in the body recommended by I.C.R.P. and this revealed that the contribution through inhalation route seemed to be greater than the other for the accumulation of Pu in the body. (auth.)

  15. Local atomic structure of α-Pu

    International Nuclear Information System (INIS)

    Espinosa, F. J.; Villella, P.; Lashley, J. C.; Conradson, S. D.; Cox, L. E.; Martinez, R.; Martinez, B.; Morales, L.; Terry, J.; Pereyra, R. A.

    2001-01-01

    The local atomic structure of α-Pu was investigated using x-ray absorption fine structure (XAFS) spectroscopy. XAFS spectra were obtained for a zone-refined α-Pu and the results were compared to 32-year-old and Ce-doped (0.34 at.%) samples. X-ray diffraction (XRD) patterns were also measured for the zone-refined and 32-year-old materials. The extent of the Bragg peaks showed that amorphization of the 32-year-old sample had not occurred despite the prolonged exposure to self-radiation. Analogous to metastable δ-Pu alloys, the local atomic structure around Pu for the zone-refined material shows the possible presence of noncrystallographic Pu-Pu distances. Conversely, the Ce and the 32-year-old sample show no evidence for such noncrystallographic distances. Disorder in the Pu local environment was found to be impurity dependent. The Ce-doped sample presented a larger Pu-Pu nearest neighbor disorder than the aged sample, although the total amount of Am, U, and He impurities was actually higher in the aged sample. The local environment around U and Ce impurities is consistent with these elements being in substitutional lattice sites. In addition, U and Ce do not introduce significant lattice distortion to their nearest neighbors. This is consistent with disorder being more related to the perturbation of the coupling between the electronic and crystal structure, or the Peierls--Jahn-Teller distortion that generates the monoclinic α-Pu structure, and less to strain fields produced in the vicinity of the impurities

  16. Transuranic and tracer simulant resuspension. [/sup 238/Pu, /sup 239/Pu, /sup 240/Pu

    Energy Technology Data Exchange (ETDEWEB)

    Sehmel, G. A.

    1977-07-01

    Plutonium resuspension results are summarized for experiments conducted at Rocky Flats, onsite on the Hanford reservation, and for winds blowing from offsite onto the Hanford reservation near the Prosser barricade boundary. In each case, plutonium resuspension was shown by increased airborne plutonium concentrations as a function of either wind speed or as compared to fallout levels. All measured airborne concentrations were below maximum permissible concentrations (MPC). Both plutonium and cesium concentrations on airborne soil were normalized by the quantity of airborne soil sampled. Airborne radionuclide concentrations in ..mu..Ci/g were related to published values for radionuclide concentrations on surface soils. For this ratio of radionuclide concentration per gram on airborne soil divided by that for ground surface soil, there are eight orders of magnitude uncertainty from 10/sup -4/ to 10/sup 4/. Horizontal plutonium fluxes on airborne nonrespirable soils at all three sites were bracketed within the same three to four orders of magnitude from 10/sup -7/ to 10/sup -3/ ..mu..Ci/(m/sup 2/ day) for plutonium-239 and 10/sup -8/ to 10/sup -5/ ..mu..Ci/(m/sup 2/ day) for plutonium-238. These are the entire experimental base for nonrespirable airborne plutonium transport. Airborne respirable plutonium-239 concentrations increased with wind speed for a southeast wind direction coming from offsite near the Hanford reservation Prosser barricade. Airborne plutonium fluxes on nonrespirable particles had isotopic ratios, /sup 240/Pu//sup 239 +240/Pu, similar to weapons grade plutonium rather than fallout plutonium. Resuspension rates were summarized for controlled inert particle tracer simulant experiments. Wind resuspension rates for tracers increased with wind speed to about the fifth power.

  17. Chemical speciation of Pu in natural waters

    International Nuclear Information System (INIS)

    Nelson, D.M.; Larsen, R.P.; Penrose, W.R.

    1983-01-01

    The behavior of plutonium in natural waters is determined to a major degree by the chemical forms which are present. We have characterized the ambient Pu in a number of surface waters with regard to its oxidation state and association with natural colloidal organic carbon compounds using a combination of field measurements and laboratory experiments. Both of these factors are shown to have a profound effect on the adsorption of Pu to natural sediments, since both complexation with organic matter and oxidation compete with adsorption. The concentration of organic carbon in the water is the key variable influencing both oxidation state and organic binding. The adsorption process conforms to the laws applicable to a reversible equilibrium with values of the distribution coefficient, K/sub D/, measured in laboratory experiments being similar to those observed for ambient Pu. Experiments using natural waters and sediments in which the Pu concentration was varied show the forms present at typical ambient concentrations (10 -17 - 10 -14 M) are the same as those found at concentrations up to 10 -7 M. Moreover, the affinity for sediments did not change with concentration indicating the binding sites for Pu had not become saturated. Thus, the behavior observed for Pu at ultratrace concentrations should remain unchanged throughout this concentration range. The studies in this report all deal with Pu in exchangeable (and hence source independent) forms and should therefore reflect the behavior toward which the plutonium from any source will tend with time. 13 references, 7 figures, 10 tables

  18. Pu(IV) reduction with hydroxyurea and its application in U/Pu separation

    International Nuclear Information System (INIS)

    Zhu Zhaowu; He Jianyu; Zhang Zefu; Song Tianbao; Zhang Yu; Zheng Weifang

    2004-01-01

    The reduction of Pu(IV) with hydroxyurea (HU) in the mixed phase of 30% TBP/OK-HNO 3 system was studied. The study results show that HU can reduce Pu(IV) to Pu(III) and the reduction rate can be expressed as -dc(Pu(IV))/dt=kc(HU)c -3.2 (HNO 3 )c mix 2 (Pu(IV))c mix -1 (Pu(III)), where k is the rate constant, and k=(896 ± 59) mol 2.3 ·L -2.3 ·min -1 at 15 degree C. With HU serves as a reductant, 16 stages count-current cascade experiment was performed using centrifugal tube to simulate U/Pu separation in the 1B contactor of Purex process. The separation factor of Pu from U and the separation factor of U from Pu reach to 5.4 x 10 4 and 1.8 x 10 5 , respectively. The amount of Pu is about 11 μg in per kg U product. (authors)

  19. Reversed phase chromatographic behaviour of Pu (III), Pu (IV) and Pu (VI) in presence of α-hydroxyisobutyric acid

    International Nuclear Information System (INIS)

    Jaison, P.G.; Telmore, V.M.; Kumar, Pranaw

    2016-01-01

    Understanding the aqueous chemistry of plutonium is important in process conditions as well as in environmental conditions. Since plutonium possesses multiple oxidation states which can coexist in solution, a reliable method for the identification of these oxidation states is essential to understand its physical and chemical processes. The identification of plutonium oxidation states is conventionally determined through a series of liquid-liquid extraction procedures using selective extractants. Spectroscopic and laser based techniques also have been used for the identification of its oxidation state in solutions. Liquid chromatographic behavior of different oxidation states of Pu and other actinide ions is reported to correlate their retention behaviour with stability constants. Objective of the present work is to study the reversed phase chromatography behavior of the three oxidation states of plutonium viz. Pu(III), Pu(IV) and Pu(VI) in presence of á-hydroxyisobutyric acid (HIBA) as an eluent

  20. Raman spectrometric determination of Pu(VI) and Pu(V) in nitric acid solutions

    International Nuclear Information System (INIS)

    Gantner, E.; Freudenberger, M.; Steinert, D.; Ache, H.J.

    1987-03-01

    The determination of Pu(VI) in nitric acid solutions by spontaneous Laser Raman Spectrometry (LRS) was investigated and a calibration curve was established using U(VI) as internal standard. In addition, the concentrations of Pu(VI) and Pu(V) as a function of time were measured by this method in Pu(VI) solutions of different acidity containing H 2 O 2 as the reducing agent. In solutions which are intensely coloured by the presence of Ru(NO) complexes Pu(VI) can also be determined by LRS using a Kr + laser as excitation source. In future experiments, the study of the Pu(IV)-interaction with Ru using LRS and spectrophotometry as analytical techniques is therefore intended. (orig.) [de

  1. Isotope ratios of 240Pu/239Pu in soil samples from different areas

    International Nuclear Information System (INIS)

    Muramatsu, Yasuyuki; Yoshida, Satoshi; Yamazaki, Shinnosuke

    2003-01-01

    Plutonium concentrations and 240 Pu/ 239 Pu atom ratios in soil samples from Japan and other areas in the world (including IAEA standard reference materials) were determined by ICP-MS. The range of 240 Pu/ 239 Pu atom ratios observed in 21 Japanese soil samples was 0.155 - 0.194 and the average was 0.180 ± 0.011, which is comparable to the global fallout value. A low ratio of about 0.05, which is derived from Pu-bomb, was found in samples from Nishiyama (Nagasaki) and Mururoa Atoll (IAEA-368), while a high ratio of about 0.31 was found in a sample from Bikini Atoll (Marshall Islands). The ratio for Irish Sea sediment (IAEA-135) was 0.21, which was higher than the global fallout value, suggesting the influence by the contamination from the Sellafield facility. The 240 Pu/ 239 Pu atom ratios in soils from the Chernobyl area were determined, and the ratio was found to be very high (about 0.4), indicating the high burn-up grade of the reactor fuel. These results show that the 240 Pu/ 239 Pu ratio can be used as a finger print to identify the source of the contamination. (author)

  2. Solution species of 239Pu [V] in the environment

    International Nuclear Information System (INIS)

    Rai, D.; Serne, R.J.; Swanson, J.L.

    1978-01-01

    Information regarding the oxidation states of Pu in environmental samples is needed for estimating its migration through the geologic media. Thermodynamic data were used to develop stability fields for different Pu species. The data indicate that in the Eh-pH range of natural aqueous environments, the dominant species of Pu is likely to be Pu[V] in relatively oxidizing environments and Pu[III] in reducing environments. Because of the lack of methods of determining Pu[V] in environmental samples containing trace concentrations of Pu, Pu[V] has not been previously identified in these samples. Plutonium [VI] is generally assumed to be the dominant species in relatively oxidizing environments. However, a combination of solvent extraction and spectrophotometric techniques used in this study show that solutions (> 10 -5 4 M Pu) in equilibrium with 239 Pu[IV] hydroxide contain Pu[V], which is in agreement with the thermodynamic predictions. Although this method could not be used conclusively with the remaining solutions ( -5 4 M Pu) contacting 239 Pu[IV] hydroxide and 239 PuO 2 , the solvent extraction and Eh-pH results are similar for all the samples suggesting the strong possibility that all samples contain Pu[V]. Thus the possibility, ignored in the past, that Pu[V] may be the dominant species in relatively oxidizing environments should be considered

  3. Determination of Pu in soil samples

    International Nuclear Information System (INIS)

    Torres C, C. O.; Hernandez M, H.; Romero G, E. T.; Vega C, H. R.

    2016-10-01

    The irreversible consequences of accidents occurring in nuclear plants and in nuclear fuel reprocessing sites are mainly the distribution of different radionuclides in different matrices such as the soil. The distribution in the superficial soil is related to the internal and external exposure to the radiation of the affected population. The internal contamination with radionuclides such as Pu is of great relevance to the nuclear forensic science, where is important to know the chemical and isotopic compositions of nuclear materials. The objective of this work is to optimize the radiochemical separation of plutonium (Pu) from soil samples and to determine their concentration. The soil samples were prepared using acid digestion assisted by microwave; purification of Pu was carried out with AG1X8 resin using ion exchange chromatography. Pu isotopes were measured using ICP-SFMS. In order to reduce the interference due to the presence of "2"3"8UH "+ in the samples, a solvent removal system (Apex) was used. In addition, the limit of detection and quantification of Pu was determined. It was found that the recovery efficiency of Pu in soil samples ranges from 70 to 93%. (Author)

  4. Determination of 238Pu, 239+240Pu, 241Pu and 241Am in radioactive waste from IPEN reactor

    International Nuclear Information System (INIS)

    Geraldo, Bianca; Taddei, Maria Helena T.; Cheberle, Sandra M.; Ferreira, Marcelo T.

    2011-01-01

    Ion exchange resin is a common type of radioactive waste arising from treatment of coolant water of the main circuit of research and nuclear power reactors. This waste contains high concentrations of fission and activation products. The management of this waste includes its characterization in order to determine and quantify specific radionuclides including those known as difficult-to-measure radionuclides (RDM). The analysis of RDMs generally involves expensive and time-consuming complex radiochemical analysis for purification and separation of the radionuclides. The objective of this work is to show an easy methodology for quantifying plutonium and americium isotopes in spent ion exchange resin, used for purification of the cooling water of the IEA-R1 reactor located at the Nuclear and Energy Research Institute, IPEN-CNEN/SP. The resins were destroyed by acid digestion, followed by purification and separation of the Pu and Am isotopes with anionic and chromatographic resins. 238 Pu, 239 + 24 '0Pu, and 24 '1Am isotopes were analyzed in an alpha spectrometer equipped with surface barrier detectors. 241 Pu isotope was analyzed by liquid scintillation counting. Chemical recovery yield ranged from 73 to 98% for Pu and 77 to 98% for Am, demonstrating that the methodology is suitable for identification and quantification of the isotopes studied in spent resins. (author)

  5. Evaluating 239Pu levels using field detectors

    International Nuclear Information System (INIS)

    Wahl, L.E.; Smith, W.J. II; Martin, B.

    1996-01-01

    At Los Alamos National Laboratory, cleanup was planned at three septic tanks where surface soil in the outfall drainage areas was found to be contaminated with 239 Pu. To meet budget and deadline constraints, a technique was developed that used field instruments to verify 239 Pu soil contamination at levels less than 2.8 Bq g -1 , the established cleanup level. The drainage areas were surveyed using a low-energy gamma probe to identify likely areas of 239 Pu contamination. Between 40 and 135 0.1-min gamma radiation measurements were obtained from each drainage area. From these data, locations were identified for subsequent screening for alpha radioactivity. Soil samples from between 11 and 18 locations at each drainage area were placed in petri dishes, dried, and counted for 10 minutes using an alpha probe. Alpha counts were then related to 239 Pu concentrations using a curve developed from local soils containing known concentrations of 239 Pu. Up to six soil samples from each drainage area, representing a range of alpha radioactivity levels, were sent for laboratory analysis of isotopic plutonium to confirm field measurement results. Analytical and field results correlated well at all but one outfall area. At this area, field measurements predicted more 239 Pu than was measured in the laboratory, indicating the presence of another alpha-emitting radionuclide that might have been missed if only laboratory analyses for plutonium had been used. This technique, which combined a large number of gamma radioactivity measurements, a moderate number of alpha radioactivity measurements, and a few isotopic plutonium measurements, allowed quick and inexpensive comparison of 239 Pu with the cleanup level

  6. Determination of 239Pu/240Pu isotopic ratio by high resolution alpha-particle spectrometry

    International Nuclear Information System (INIS)

    Amoudry, F.; Burger, P.

    1983-05-01

    The development of passivated ion-implanted silicon detectors and of very thin alpha-particle sources improves the resolution of alpha-particle spectra and allows to separate energy pics up to now unseparate. The 239 Pu/ 240 Pu isotopic ratio of a mixture has been measured using the alpha spectrometry deconvolution code DEMO [fr

  7. Transmutation of 129I, 237Np, 238Pu, 239Pu, and 241Am using ...

    Indian Academy of Sciences (India)

    Results of transmutation studies of 129I, 237Np, 238Pu, 239Pu and 241Am are presented. Keywords. ... J Adam et al. Table 1. Samples properties for 0.7 and 1 GeV experiments. ..... If we suppose that this conclusion is true also for ratios in ...

  8. Improved MOX fuel calculations using new Pu-239, Am-241 and Pu-240 evaluations

    International Nuclear Information System (INIS)

    Noguere, G.; Bouland, O.; Bernard, D.; Leconte, P.; Blaise, P.; Peneliau, Y.; Vidal, J.F.; Saint Jean, C. de; Leal, L.; Schilleebeeckx, P.; Kopecky, S.; Lampoudis, C.

    2013-01-01

    Several studies based on the JEFF-3.1.1 nuclear data library show a systematic over-estimation of the critical keff for core configurations of MOX fuel assemblies. The present work investigates possible improvements of the C/E results by using new evaluations for Am-241, Pu-239 and Pu-240. The work reported in this paper demonstrates the performances of the new Am-241 evaluation based on capture and transmission data measured at the IRMM. For Pu-239, the new evaluation, established in the frame of the WPEC/SG-34, is able to explain a systematic discrepancy observed between different EOLE experiments. The combination of the Am-241 and Pu-239 evaluations demonstrates the necessity to improve the radiation width of the first resonance of Pu-240

  9. Worldwide data on fluxes of 239,240Pu, 238Pu to the oceans

    International Nuclear Information System (INIS)

    Aarkrog, A.

    1987-04-01

    According to measurements (GEOSECS) the world's oceans contain approximately 16 PBq 239,240 Pu, of which one-fourth is in the Atlantic and three-fourths in the Pacific Ocean. The expected inventory (from nuclear weapons testing) in the world's oceans is 12 PBq 239,240 Pu including local fallout at the test sites. In the Irish Sea a local contamination of 0.3 PBq 239,240 Pu from the Sellafield reprocessing plant resides in the sediments. No other sources than fallout and reprocessing add significantly to the 239,240 Pu inventories in the oceans. The discrepancy between measurements and expectations are assumed to be due to an underestimate of the rainfall and dry fallout (seaspray) and thus of the Pu-deposition over the oceans, but may also to some degree be due to inadequate sampling

  10. Fermiology of PuCoGa{sub 5} and of related Pu-115 compounds

    Energy Technology Data Exchange (ETDEWEB)

    Oppeneer, P.M. [Department of Physics, Box 530, Uppsala University, S-751 21 Uppsala (Sweden)], E-mail: peter.oppeneer@fysik.uu.se; Shick, A.B. [Institute of Physics, Academy of Sciences of the Czech Republic, CZ-18221 Prague (Czech Republic); Rusz, J. [Department of Electronic Structures, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, CZ-121 16 Prague 2 (Czech Republic); Lebegue, S. [Laboratoire de Cristallographie et de Modelisation des Materiaux Mineraux et Biologiques, CNRS-Universite Henri Poincare, B.P. 239, F-54506 Vandoeuvre-les-Nancy (France); Eriksson, O. [Department of Physics, Box 530, Uppsala University, S-751 21 Uppsala (Sweden)

    2007-10-11

    We report computational investigations of the electronic structures of the superconducting Pu-compounds PuCoGa{sub 5} as well as of the non-superconducting compounds PuFeGa{sub 5} and PuNiGa{sub 5}. To capture the localization behavior of the Pu 5f electrons, we apply two computational approaches, which are both rooted in the density-functional theory: the local spin-density approximation (LSDA) and the around mean field (AMF) LSDA+U approach. The latter is applicable to moderately localized 5f electrons while the former is applicable to delocalized 5f electrons. Our LSDA calculations show that the Fermi surfaces of the three Pu-115 compounds are sensitive to the amount of band filling, i.e., the number of electrons of the 3d element. Precisely at the electron filling corresponding to PuCoGa{sub 5} the Fermi surface has a particularly two-dimensional shape. AMF-LSDA+U calculations (with a Coulomb U of about 3 eV and exchange J of 0.6 eV) lead to a non-magnetic ground state for PuCoGa{sub 5}, in which the 5f states are shifted to a higher binding energy, in better agreement with photoemission data. The Fermi surface of PuCoGa{sub 5} computed with the AMF-LSDA+U approach is nonetheless rather two-dimensional and similar to the LSDA Fermi surface. The AMF-LSDA+U approach with a Coulomb U of {approx}3 eV would thus predict an electronic structure for PuCoGa{sub 5} in accord with several experimental data.

  11. Redefining design criteria for Pu-238 gloveboxes

    International Nuclear Information System (INIS)

    Acosta, S.V.

    1998-01-01

    Enclosures for confinement of special nuclear materials (SNM) have evolved into the design of gloveboxes. During the early stages of glovebox technology, established practices and process operation requirements defined design criteria. Proven boxes that performed and met or exceeded process requirements in one group or area, often could not be duplicated in other areas or processes, and till achieve the same success. Changes in materials, fabrication and installation methods often only met immediate design criteria. Standardization of design criteria took a big step during creation of ''Special-Nuclear Materials R and D Laboratory Project, Glovebox standards''. The standards defined design criteria for every type of process equipment in its most general form. Los Alamos National Laboratory (LANL) then and now has had great success with Pu-238 processing. However with ever changing Environment Safety and Health (ES and H) requirements and Ta-55 Facility Configuration Management, current design criteria are forced to explore alternative methods of glovebox design fabrication and installation. Pu-238 fuel processing operations in the Power Source Technologies Group have pushed the limitations of current design criteria. More than half of Pu-238 gloveboxes are being retrofitted or replaced to perform the specific fuel process operations. Pu-238 glovebox design criteria are headed toward process designed single use glovebox and supporting line gloveboxes. Gloveboxes that will house equipment and processes will support TA-55 Pu-238 fuel processing needs into the next century and extend glovebox expected design life

  12. Localized 5f electrons in superconducting PuCoIn5: consequences for superconductivity in PuCoGa5

    International Nuclear Information System (INIS)

    Bauer, E D; Altarawneh, M M; Tobash, P H; Gofryk, K; Ayala-Valenzuela, O E; Mitchell, J N; McDonald, R D; Mielke, C H; Ronning, F; Scott, B L; Thompson, J D; Griveau, J-C; Colineau, E; Eloirdi, R; Caciuffo, R; Janka, O; Kauzlarich, S M

    2012-01-01

    The physical properties of the first In analog of the PuMGa 5 (M = Co, Rh) family of superconductors, PuCoIn 5 , are reported. With its unit cell volume being 28% larger than that of PuCoGa 5 , the characteristic spin-fluctuation energy scale of PuCoIn 5 is three to four times smaller than that of PuCoGa 5 , which suggests that the Pu 5f electrons are in a more localized state relative to PuCoGa 5 . This raises the possibility that the high superconducting transition temperature T c = 18.5 K of PuCoGa 5 stems from the proximity to a valence instability, while the superconductivity at T c = 2.5 K of PuCoIn 5 is mediated by antiferromagnetic spin fluctuations associated with a quantum critical point. (fast track communication)

  13. Suggestions for future Pu fuel cycle designs

    International Nuclear Information System (INIS)

    Serfontein, Dawid E.; Mulder, Eben J.; Reitsma, Frederik

    2013-01-01

    Recommended follow-up Pu Studies: • Verification of VSOP-A vs. VSOP 99/05, by comparison with MCNP. • DLOFC temperatures with Multi-group Tinte. • Redesign of the reactor: - Replace small concentrated Pu fuel kernels with large (500 μm diameter) diluted kernels to reduce burn-up. - Switch from the direct Brayton cycle to the indirect Rankine steam cycle to reduce fuel temperatures. - Add neutron poisons to the reflectors to suppress power and temperature peaks and to produce negative uniform temperature reactivity coefficients

  14. Fabrication of 12% 240Pu calorimetry standards

    International Nuclear Information System (INIS)

    Long, S.M.; Hildner, S.; Gutierrez, D.; Mills, C.; Garcia, W.; Gurule, C.

    1995-01-01

    Throughout the DOE complex, laboratories are performing calorimetric assays on items containing high burnup plutonium. These materials contain higher isotopic range and higher wattages than materials previously encountered in vault holdings. Currently, measurement control standards have been limited to utilizing 6% 240 Pu standards. The lower isotopic and wattage value standards do not complement the measurement of the higher burnup material. Participants of the Calorimetry Exchange (CALEX) Program have identified the need for new calorimetric assay standards with a higher wattage and isotopic range. This paper describes the fabrication and verification measurements of the new CALEX standard containing 12% 240 Pu oxide with a wattage of about 6 to 8 watts

  15. [Acupuncture messenger--Pu Xiang-cheng].

    Science.gov (United States)

    Du, Huai-bin; Liang, Fan-rong

    2011-06-01

    PU Xiang-cheng is the eminent acupuncture master in modern history of China. He studied diligently in early years and devoted his life to the cause of acupuncture practice and education in Chinese medicine. Combination of acupuncture and herbal medicine, coordination of acupuncture and moxibustion, unique application of acupoints, flexible combination of acupoints and focusing on needling techniques are the essence of his academic thoughts. The life of PU Xiang-cheng, the acupuncture master, and his major academic thoughts are described in this paper, so as to commemorate his contributions to acupuncture theory, practice and promotions.

  16. Multilevel resonance parameters of 241Pu

    International Nuclear Information System (INIS)

    Weston, L.W.; Todd, J.H.

    1978-01-01

    The data previously reported by the authors on the neutron fission and capture cross sections of 241 Pu were simultaneously fit with the Adler formalism to obtain multilevel resonance parameters. The neutron energy range of the fit was 0.01 to 100 eV. The 241 Pu cross sections in the resonance region of neutron energies are complex, and the Adler parameters present an efficient method of representing these cross sections, which are important for plutonium-fueled reactors. The parameters represent the data to an accuracy within the quoted experimental errors. 5 figures, 2 tables

  17. Pu sorption to activated conglomerate anaerobic bacteria

    International Nuclear Information System (INIS)

    Sasaki, Takayuki; Kudo, Akira

    2001-01-01

    The sorption of Pu to the anaerobic bacteria activated under specific conditions of temperature, pH and depleted nutrients after long dormant period was investigated. After 4 h at neutral pH, the distribution coefficient (K d ) between bacteria and aqueous phase at 308 and 278 K had around 10 3 to 10 4 . After over 5 days, however, the K d at only 308 K had increased to over 10 5 . Sterilized (dead) and dormant anaerobic bacteria adsorbed Pu to the same extent. (author)

  18. Oxidation behaviour of plutonium rich (U, Pu)C and (U, Pu)O{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Sali, S.K., E-mail: sksali@barc.gov.in [Fuel Chemistry Division (India); Kulkarni, N.K.; Phatak, Rohan [Fuel Chemistry Division (India); Agarwal, Renu [Product Development Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2016-10-15

    Oxidation behaviour of (U{sub 0.3}Pu{sub 0.7})C{sub 1.06} was investigated in air by heating samples up to 1073 K and 1273 K. Thermogravimetry (TG) of the samples and X-ray powder diffraction (XRD) of the intermediate products were used to understand the phenomenon taking place during this process. Theoretical calculations were carried out to understand the multiple phase changes taking place during oxidation of carbide. Theoretical results were validated by XRD analysis of the products obtained at different stages of oxidation. The final oxidized products were found to be a single FCC phase with O/M = 2.15 (M = U + Pu). Oxidation kinetic studies of (U{sub 0.3}Pu{sub 0.7})O{sub 2} and (U{sub 0.47}Pu{sub 0.53})O{sub 2} were carried out in dry air, using thermogravimetry, under non-isothermal conditions. The activation energy of oxidation was found to be 49 and 70 kJ/mol, respectively. Lattice parameter dependence on Pu/M and O/M of plutonium rich mixed oxide (MOX) was established using combined results of XRD and TG analysis of (U{sub 0.3}Pu{sub 0.7})O{sub 2+x} and (U{sub 0.47}Pu{sub 0.53})O{sub 2+x}.

  19. Presence of plutonium isotopes, {sup 239}Pu and {sup 240}Pu, in soils from Chile

    Energy Technology Data Exchange (ETDEWEB)

    Chamizo, E., E-mail: echamizo@us.es [Centro Nacional de Aceleradores, Avda. Thomas Alba Edison, 7, 41092 Sevilla (Spain); Garcia-Leon, M., E-mail: manugar@us.es [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, Avda. Reina Mercedes sn, 41012 Seville (Spain); Peruchena, J.I., E-mail: jiperuchena@gmail.com [Centro Nacional de Aceleradores, Avda. Thomas Alba Edison, 7, 41092 Sevilla (Spain); Cereceda, F., E-mail: francisco.cereceda@usm.cl [Laboratorio de Quimica Ambiental, Centro de Tecnologias Ambientales (CETAM), Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile); Vidal, V., E-mail: victor.vidal@usm.cl [Laboratorio de Quimica Ambiental, Centro de Tecnologias Ambientales (CETAM), Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile); Pinilla, E., E-mail: epinilla@unex.es [Departamento de Quimica Analitica, Facultad de Ciencias, Universidad de Extremadura, Avda. de Elvas sn, 06071 Badajoz (Spain); Miro, C., E-mail: cmiro@unex.es [Departamento de Fisica Aplicada, Universidad de Extremadura, Avda. de la Universidad sn, 10071 Caceres (Spain)

    2011-12-15

    Plutonium is present in every environmental compartment, due to a variety of nuclear activities. The Southern Hemisphere has received about 20% of the global {sup 239}Pu and {sup 240}Pu environmental inventory, with an important contribution of the so-called tropospheric fallout from both the atmospheric nuclear tests performed in the French Polynesia and in Australia by France and United Kingdom, respectively. In this work we provide new data on the impact of these tests to South America through the study of {sup 239}Pu and {sup 240}Pu in soils from different areas of Northern, Central and Southern Chile. The obtained results point out to the presence of debris from the French tests in the 20-40 Degree-Sign Southern latitude range, with {sup 240}Pu/{sup 239}Pu atomic ratios quite heterogeneous and ranging from 0.02 to 0.23. They are significantly different from the expected one for the global fallout in the Southern Hemisphere for the 30-53 Degree-Sign S latitude range (0.185 {+-} 0.047), but they follow the same trend as the reported values by the Department of Energy of United States for other points with similar latitudes. The {sup 239+240}Pu activity inventories show as well a wider variability range in that latitude range, in agreement with the expected heterogeneity of the contamination.

  20. Presence of plutonium isotopes, 239Pu and 240Pu, in soils from Chile

    International Nuclear Information System (INIS)

    Chamizo, E.; García-León, M.; Peruchena, J.I.; Cereceda, F.; Vidal, V.; Pinilla, E.; Miró, C.

    2011-01-01

    Plutonium is present in every environmental compartment, due to a variety of nuclear activities. The Southern Hemisphere has received about 20% of the global 239 Pu and 240 Pu environmental inventory, with an important contribution of the so-called tropospheric fallout from both the atmospheric nuclear tests performed in the French Polynesia and in Australia by France and United Kingdom, respectively. In this work we provide new data on the impact of these tests to South America through the study of 239 Pu and 240 Pu in soils from different areas of Northern, Central and Southern Chile. The obtained results point out to the presence of debris from the French tests in the 20–40° Southern latitude range, with 240 Pu/ 239 Pu atomic ratios quite heterogeneous and ranging from 0.02 to 0.23. They are significantly different from the expected one for the global fallout in the Southern Hemisphere for the 30–53°S latitude range (0.185 ± 0.047), but they follow the same trend as the reported values by the Department of Energy of United States for other points with similar latitudes. The 239+240 Pu activity inventories show as well a wider variability range in that latitude range, in agreement with the expected heterogeneity of the contamination.

  1. Quantitative Assay of Pu-239 and Pu-240 by Neutron Transmission Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, E

    1971-04-15

    A method for quantitative assay of 239Pu and 240Pu has been tested at the reactor R1 in Stockholm. The method makes use of a fast chopper to measure the neutron transmission through a sample around the main resonances of these two isotopes - at 0.296 eV in 239Pu and at 1.056 eV in 240Pu. The transmission data measured are then combined with the known resonance cross sections to give the content of the isotopes. The method is nondestructive, i.e., one can use fuel pins as samples, even highly irradiated ones. A time-of-flight spectrometer of moderate capacity, like our fast chopper, is sufficient as the resonances are located at low energy. Altogether five samples have been used in the tests of the method. The results have been compared with mass spectrometer values. This comparison came out quite well for 239Pu whereas the chopper results for 240Pu were more than 10 per cent higher than the mass spectrometer results. This large deviation might be due to errors in the resonance cross section for 240Pu used in the analysis of the transmission data from the chopper. The best possible accuracy for a 15-hour run with our equipment is +- 1 per cent for 239Pu and +- 2 per cent for 240Pu, obtained for thick samples - about 3 x 1020 atoms per cm2 for each isotope. The accuracy corresponds to 68 per cent confidence level and does not include any contribution from the uncertainty in the resonance cross section

  2. Evaluation of nuclear data of {sup 244}Pu and {sup 237}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Tsuneo; Konshin, V.A. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1995-10-01

    The evaluation of nuclear data for {sup 244}Pu and {sup 237}Pu was made in the neutron energy region from 10{sup -5} eV to 20 MeV. For the both nuclides, the total, elastic and inelastic scattering, fission, capture, (n,2n) and (n,3n) reaction cross sections were evaluated on the basis of theoretical calculation. The resonance parameters were given for {sup 244}Pu. The angular and energy distributions of secondary neutrons were also estimated for the both nuclides. The results were compiled in the ENDF-5 format and will be adopted in JENDL Actinoid File. (author).

  3. Distribution of 238Pu and 239240Pu in aquatic macrophytes from a midwestern watershed

    International Nuclear Information System (INIS)

    Wayman, C.W.; Bartelt, G.E.; Alberts, J.J.

    1977-01-01

    Aquatic macrophytes were collected in the Great Miami River, Ohio, above and below Miamisburg and in the canal and ponds, near the Mound Laboratory, which contain sediments of a high activity (approximately 10 3 to 10 6 times) relative to the river sediments. Macrophytes collected in the river below Miamisburg have higher activities of 238 Pu than those collected from above the city. Macrophytes from the canal and ponds contain high specific activities of 238 Pu and 239 , 240 Pu with the exception of cattails grown in the ponds. Concentration factors are reported and discussed with reference to possible modes of plutonium accumulation and distribution within the plants

  4. Plutonium diffusion in advanced fuels (U,Pu)(C,O) and (U,Pu)(C,N)

    International Nuclear Information System (INIS)

    Bradbury, M.H.; Matzke, H.

    1983-01-01

    The self-diffusion of 238 Pu was measured in an oxicarbide (U,Pu)(C,O) and a carbonitride (U,Pu) (C,N). The activation enthalpies were 447 and 347 kJ mol -1 , respectively. The carbonitrides were confirmed to fall into three classes: carbide-like compositions with less than 30% nitrogen in the metalloid lattice, nitride-like composition with more than 70% nitrogen and with reduced atomic mobilities, and carbonitrides with about 50% nitrogen showing an intermediate behavior. The oxicarbide showed diffusion coefficients slightly larger than those of pure carbides

  5. Experimental Benchmarking of Pu Electronic Structure

    International Nuclear Information System (INIS)

    Tobin, J.G.; Moore, K.T.; Chung, B.W.; Wall, M.A.; Schwartz, A.J.; Ebbinghaus, B.B.; Butterfield, M.T.; Teslich, N.E. Jr.; Bliss, R.A.; Morton, S.A.; Yu, S.W.; Komesu, T.; Waddill, G.D.; van der Laan, G.; Kutepov, A.L.

    2008-01-01

    The standard method to determine the band structure of a condensed phase material is to (1) obtain a single crystal with a well defined surface and (2) map the bands with angle resolved photoelectron spectroscopy (occupied or valence bands) and inverse photoelectron spectroscopy (unoccupied or conduction bands). Unfortunately, in the case of Pu, the single crystals of Pu are either nonexistent, very small and/or having poorly defined surfaces. Furthermore, effects such as electron correlation and a large spin-orbit splitting in the 5f states have further complicated the situation. Thus, we have embarked upon the utilization of unorthodox electron spectroscopies, to circumvent the problems caused by the absence of large single crystals of Pu with well-defined surfaces. Our approach includes the techniques of resonant photoelectron spectroscopy, x-ray absorption spectroscopy, electron energy loss spectroscopy, Fano Effect measurements, and Bremstrahlung Isochromat Spectroscopy, including the utilization of micro-focused beams to probe single-crystallite regions of polycrystalline Pu samples.

  6. Recycling U and Pu in LWR

    International Nuclear Information System (INIS)

    Zheng Hualing.

    1986-01-01

    This article, from viewpoints of technical feasibility, safety evaluation and socioeconomic benefit-risk analysis, introduces and comments on history and status of recycling U and Pu in LWR, dealing with reactor, reprocessing, conversion and fuel element fabrication et al. Author has analysed LWR fuel cycle strategies in China and made a proposal

  7. The unrivalled expertise for Pu recycling

    International Nuclear Information System (INIS)

    Fournier, W.; Pouilloux, M.

    1997-01-01

    Relying on the outstanding performances of the reprocessing facilities and the growing fabrication facilities, the in-reactor Pu recycling program in France and in other European countries is steadily implemented and has reached full-scale industrial operation. The RCR strategy -Reprocessing, Conditioning and Recycling- developed by COGEMA is now a well proven industrial reality. In 1997, plutonium recycling through MOX fuel is a mature industry, with successful operational experience and large-scale fabrication plants. In this field, COGEMA is the main actor, on operating simultaneously three complete multidesign fuel production plants: MELOX plant (in Marcoule), CADARACHE plant and DESSEL plant (in Belgium). Present MOX production capacity available to COGEMA fits 175 tHM per year and will be extended to reach about 325 tHM in the year 2000, that will represent 75% of the total MOX fabrication capacity in Europe. The industrial mastery and the high production level in MOX production assured by high technology processes confers COGEMA an unrivalled expertise for Pu recycling. This allows COGEMA to be a major actor in Pu-based fuels in the coming second nuclear era with advanced fuel cycles. The paper depicts the steps of the progressive advance of COGEMA to reach the Pu recycling expertise. (author)

  8. Review of 241 Pu resonance parameters

    International Nuclear Information System (INIS)

    Derrien, H.

    1981-10-01

    The status of 241 Pu resonance parameters is reviewed. The most important recent results are compared in some energy ranges, both from single level and multilevel point of view. It appears that an accurate set of resonance parameters is not still obtained for a general description of the cross-sections in the resonance region. Some recommendations are given for further experiments or evaluations

  9. Nitrate Anion Exchange in Pu-238 Aqueous Scrap Recovery Operations

    International Nuclear Information System (INIS)

    Pansoy-Hjelvik, M.E.; Silver, G.L.; Reimus, M.A.H.; Ramsey, K.B.

    1999-01-01

    Strong base, nitrate anion exchange (IX) is crucial to the purification of 238 Pu solution feedstocks with gross levels of impurities. This paper discusses the work involved in bench scale experiments to optimize the nitrate anion exchange process. In particular, results are presented of experiments conducted to (a) demonstrate that high levels of impurities can be separated from 238 Pu solutions via nitrate anion exchange and, (b) work out chemical pretreatment methodology to adjust and maintain 238 Pu in the IV oxidation state to optimize the Pu(IV)-hexanitrato anionic complex sorption to Reillex-HPQ resin. Additional experiments performed to determine the best chemical treatment methodology to enhance recovery of sorbed Pu from the resin, and VIS-NIR absorption studies to determine the steady state equilibrium of Pu(IV), Pu(III), and Pu(VI) in nitric acid are discussed

  10. Structures and potential energy functions of Pu3 molecule

    International Nuclear Information System (INIS)

    Meng Daqiao; Jiang Gang; Liu Xiaoya; Luo Deli; Zhu Zhenghe

    2001-01-01

    Density functional (B3LYP) method with relativistic effective core potential (RECP) has been used to optimize the structures of Pu 2 and Pu 3 molecules. The results show that the ground states of Pu 2 and Pu 3 molecules are of D ∞h and D 3h symmetry, and of 13 and 19 fold, respectively. The spectral constants of Pu 2 , ω e = 52.3845 cm -1 and ω e x e = 0.0201 cm -1 , and the harmonic frequencies of Pu 3 , ν 1 = 56.9007 cm -1 , ν 2 = 57.1816 cm - '1 and ν 3 = 64.0785 cm -1 , have also been obtained on the B3LYP/RECP level. The potential energy functions of Pu 2 and Pu 3 have been derived, for the first time so far as known, from normal equation fitting and the many-body expansion theory

  11. Radiation protection problems with sealed Pu radiation sources

    International Nuclear Information System (INIS)

    Naumann, M.; Wels, C.

    1982-01-01

    A brief outline of the production methods and most important properties of Pu-238 and Pu-239 is given, followed by an overview of possibilities for utilizing the different types of radiation emitted, a description of problems involved in the safe handling of Pu radiation sources, and an assessment of the design principles for Pu-containing alpha, photon, neutron and energy sources from the radiation protection point of view. (author)

  12. Transplacental absorption of 238Pu in rats and guinea pigs

    International Nuclear Information System (INIS)

    Sullivan, M.F.

    1980-01-01

    Pregnant rats and guinea pigs were injected intravenously with 238 Pu citrate to determine if the potential for in utero accumulation of 238 Pu by these two species is related to the stage of development at which immunity is gained. Although guinea pigs retained more 238 Pu after birth than rats, the difference was not significant

  13. Determination of Pu in soil samples; Determinacion de Pu en muestras de suelo

    Energy Technology Data Exchange (ETDEWEB)

    Torres C, C. O.; Hernandez M, H.; Romero G, E. T. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Vega C, H. R., E-mail: carioli_32907@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

    2016-10-15

    The irreversible consequences of accidents occurring in nuclear plants and in nuclear fuel reprocessing sites are mainly the distribution of different radionuclides in different matrices such as the soil. The distribution in the superficial soil is related to the internal and external exposure to the radiation of the affected population. The internal contamination with radionuclides such as Pu is of great relevance to the nuclear forensic science, where is important to know the chemical and isotopic compositions of nuclear materials. The objective of this work is to optimize the radiochemical separation of plutonium (Pu) from soil samples and to determine their concentration. The soil samples were prepared using acid digestion assisted by microwave; purification of Pu was carried out with AG1X8 resin using ion exchange chromatography. Pu isotopes were measured using ICP-SFMS. In order to reduce the interference due to the presence of {sup 238}UH {sup +} in the samples, a solvent removal system (Apex) was used. In addition, the limit of detection and quantification of Pu was determined. It was found that the recovery efficiency of Pu in soil samples ranges from 70 to 93%. (Author)

  14. Neutron inelastic-scattering cross sections of 232Th, 233U, 235U, 238U, 239Pu and 240Pu

    International Nuclear Information System (INIS)

    Smith, A.B.; Guenther, P.T.

    1982-01-01

    Differential-neutron-emission cross sections of 232 Th, 233 U, 235 U, 238 U, 239 Pu and 240 Pu are measured between approx. = 1.0 and 3.5 MeV with the angle and magnitude detail needed to provide angle-integrated emission cross sections to approx. 232 Th, 233 U, 235 U and 238 U inelastic-scattering values, poor agreement is observed for 240 Pu, and a serious discrepancy exists in the case of 239 Pu

  15. Contribution to the study of the upper valence states of Pu

    International Nuclear Information System (INIS)

    Musante, Yves.

    1975-01-01

    The properties of the Pu(VI) and Pu(VII) ions in aqueous solutions were investigated: spectrophotometric study of the formation of PuO 2 2+ complexes with hydroxyl ions; electrochemical study of PuO 2 2+ ; preparation, determination and coprecipitation of Pu(VII); electrochemical study of Pu(VII). A preliminary research was made on the chemistry of Pu in non-aqueous solutions especially the dissolution and the determination of Pu in propylene carbonate [fr

  16. Pu speciation in actual and simulated aged wastes

    Energy Technology Data Exchange (ETDEWEB)

    Lezama-pacheco, Juan S [Los Alamos National Laboratory; Conradson, Steven D [Los Alamos National Laboratory

    2008-01-01

    X-ray Absorption Fine Structure Spectroscopy (XAFS) at the Pu L{sub II/III} edge was used to determine the speciation of this element in (1) Hanford Z-9 Pu crib samples, (2) deteriorated waste resins from a chloride process ion-exchange purification line, and (3) the sediments from two Waste Isolation Pilot Plant Liter Scale simulant brine systems. The Pu speciation in all of these samples except one is within the range previously displayed by PuO{sub 2+x-2y}(OH){sub y}{center_dot}zH{sub 2}O compounds, which is expected based on the putative thermodynamic stability of this system for Pu equilibrated with excess H{sub 2}O and O{sub 2} under environmental conditions. The primary exception was a near neutral brine experiment that displayed evidence for partial substitution of the normal O-based ligands with Cl{sup -} and a concomitant expansion of the Pu-Pu distance relative to the much more highly ordered Pu near neighbor shell in PuO{sub 2}. However, although the Pu speciation was not necessarily unusual, the Pu chemistry identified via the history of these samples did exhibit unexpected patterns, the most significant of which may be that the presence of the Pu(V)-oxo species may decrease rather than increase the overall solubility of these compounds. Several additional aspects of the Pu speciation have also not been previously observed in laboratory-based samples. The molecular environmental chemistry of Pu is therefore likely to be more complicated than would be predicted based solely on the behavior of PuO{sub 2} under laboratory conditions.

  17. Redox reactions of Pu(IV) and Pu(III) in the presence of acetohydroxamic acid in HNO(3) solutions.

    Science.gov (United States)

    Tkac, Peter; Precek, Martin; Paulenova, Alena

    2009-12-21

    The reduction of Pu(IV) in the presence of acetohydroxamic acid (HAHA) was monitored by vis-NIR spectroscopy. All experiments were performed under low HAHA/Pu(IV) ratios, where only the Pu(IV)-monoacetohydroxamate complex and Pu uncomplexed with HAHA were present in relevant concentrations. Time dependent concentrations of all absorbing species were resolved using molar extinction coefficients for Pu(IV), Pu(III), and the Pu(AHA)(3+) complex by deconvolution of spectra. From fitting of the experimental data by rate equations integrated by a numeric method three reactions were proposed to describe a mechanism responsible for the reduction and oxidation of plutonium in the presence of HAHA and HNO(3). Decomposition of Pu(AHA)(3+) follows a second order reaction mechanism with respect to its own concentration and leads to the formation of Pu(III). At low HAHA concentrations, a two-electron reduction of uncomplexed Pu(IV) with HAHA also occurs. Formed Pu(III) is unstable and slowly reoxidizes back to Pu(IV), which, at the point when all HAHA is decomposed, can be catalyzed by the presence of nitrous acid.

  18. Determination of 240Pu/239Pu isotope ratios in Kara Sea and Novaya Zemlya sediments using accelerator mass spectrometry

    International Nuclear Information System (INIS)

    Oughton, D.H.; Skipperud, L.; Salbu, B.; Fifield, L.K.; Cresswell, R.C.; Day, J.P.

    1999-01-01

    Accelerator mass spectrometry (AMS) has been used to determine Pu activity concentrations and 240 Pu/ 239 Pu isotope ratios in sediments from the Kara Sea and radioactive waste dumping sites at Novaya Zemlya. Measured 239,240 Pu activities ranged from 0.06 - 9.8 Bq/kg dry weight, 240 Pu/ 239 Pu atom ratios ranged from 0.13 to 0.28, and 238 Pu/ 239,240 Pu activity ratios from 0.02 to 0.6. Perturbations from global fallout isotope ratios were evident at three sites: the Yenisey Estuary and Abrosimov Fjords where 240 Pu/ 239 Pu ratios were lower (0.13-0.14); and Stepovogo Fjord sediments where ratios were higher (up to 0.28) than fallout ratios. Based on procedural blanks, detection limits for AMS were below 1 fg Pu and the method showed good precision for isotope ratio measurements, minimal matrix, interference and memory effects. For high level samples, comparison between alpha spectrometry and AMS gave good agreement for measurement of 239,240 Pu activity concentrations. (author)

  19. 238Pu fuel form activities, March 1-September 30, 1985

    International Nuclear Information System (INIS)

    1986-01-01

    The SRP portion of this report summarizes production 238 PuO 2 fuel forms for use in radioisotopic thermoelectric generators (RTG's) in the Plutonium Fuel Form (PuFF) Facility at the Savannah River Plant. The PuFF Facility began producing iridium-encapsulated, 62.5-watt 238 PuO 2 right circular cylinders for GPHS (General Purpose Heat Source) RTG's in June 1980; this program was completed in December 1983. The PuFF Facility has been placed in a production readiness mode of operation pending funding of additional heat source programs

  20. Comparison of the ENDF/B-V and SOKRATOR evaluations of 235U, 239Pu, 240Pu and 241Pu at low neutron energies

    International Nuclear Information System (INIS)

    de Saussure, G.; Wright, R.Q.

    1981-01-01

    The US and USSR's most recent evaluationsof 235 U, 239 Pu, 240 Pu and 241 Pu are compared over the thermal region and over the first few resonances. The two evaluations rest on essentially the same experimental data base and the differences reflect different approaches to the representation of the cross sections or different weightings of the experimental results. It is found that over the thermal and resolved ranges the two evaluations are very similar. Some differences in approaches are briefly discussed

  1. Thermodynamic evaluation of liquid Cd cathode containing U and Pu

    International Nuclear Information System (INIS)

    Kurata, Masaki; Uozumi, Koichi; Kato, Tetsuya; Iizuka, Masatoshi

    2009-01-01

    In our previous study, a mixture of U and Pu was recovered in liquid Cd cathode from molten salt under various conditions of the U:Pu ratio. Two important things were observed. The first was that three kinds of precipitated phase had been detected in the saturated liquid Cd cathode, such as a U metal and two kinds of U-Pu-Cd compound. The compositions of the compounds were roughly (U+Pu):Cd=1:11 and (U+Pu):Cd=1:6. The second was that the U metal had selectively precipitated in the saturated liquid Cd cathode under the condition that the U:Pu ratio is higher than about 0.8 in the liquid Cd phase. In the present study, phase diagrams were evaluated by the CALPHAD method on the liquid Cd cathode containing U and Pu. The U-Pu-Cd compounds were modeled as MCd 11 -type and MCd 6 -type, respectively, based on the reported binary phase diagrams of U-Cd and Pu-Cd. The calculated result reasonably agreed with the experimental observations. The variations in the U and Pu activities were estimated along with the U:Pu ratio, which is related to the precipitation of various phases in the liquid Cd cathode. (author)

  2. Low level scintillation counting of 239Pu

    International Nuclear Information System (INIS)

    Fueloep, M.; Minarik, F.; Cierna, V.

    1984-01-01

    For measuring the content of 239 Pu in samples taken from the working or living environment, methods should be used which are sufficiently sensitive for determining activities of the order of 10 -3 Bq. It is useful to use liquid scintillators for reasons of their 4π geometry and the exclusion of kinetic energy losses of particles detected in the sample and on the path between the sample and the detector. The method of background discrimination according to pulse shape may be used to suppress gamma background in the area of alpha particle peaks to the level 2.5x10 -4 s -1 . The diagram is given of electronic circuits for shape discrimination. The scintillator used was a SLS-31 with a PBD activator, a POPOP spectrum shifter and a mixture of solvents: toluene, dioxane and methanol. The efficiency of 239 Pu alpha particle detection is estimated at 78% and may further be improved by improving shape discrimination. (M.D.)

  3. Carbothermic synthesis of (Cm,Pu)N

    International Nuclear Information System (INIS)

    Takano, Masahide; Itoh, Akinori; Akabori, Mitsuo; Ogawa, Toru; Numata, Masami; Okamoto, Hisato

    2001-01-01

    Nitrides are being considered as fuel candidates for the transmutation of minor actinides. Carbothermic reduction of oxides is an effective method to fabricate nitride fuels. In this study, (Cm 0.40 ,Pu 0.60 )N was synthesized by the carbothermic reduction of the mixed oxide in N 2 . By applying excess carbon, an oxide-free nitride was obtained at 1773 K. The lattice parameter of the oxide-free sample was 0.4948 nm, and that of the nitride with oxides was 0.4974 nm. The former value agreed well with that estimated from the literature values for CmN and PuN. The larger lattice parameter of the latter sample is considered to be due to the oxygen dissolved in the nitride. (authors)

  4. Artificial radioactivity and marine environment. Study of 238Pu, 239Pu+240Pu, 241Pu and 241Am in the Mediterranean sea

    International Nuclear Information System (INIS)

    Ballestra, Serge.

    1980-10-01

    This paper is in two parts. Part one is about the methods for analyzing transuranium elements particularly the development of an analytical process for plutonium and for perfecting an Americium analyzing method, capable of treating samples of 200 litres of sea water, 100 grams of sediment and 100 grams of biological matter. Part two concerns the in situ determinations carried out within the scope of the study on the distribution and behaviour of transuranium elements in the Mediterranean sea. The high sea studies concerned the effects of atmospheric fall out and the vertical distribution of Pu and Am. Studies along the coasts enabled a quantitative study to be made of the contribution of rivers to the Mediterranean and to study the distribution of Pu along the French Mediterranean coast line [fr

  5. Age and carcinogenesis of 239Pu

    International Nuclear Information System (INIS)

    Mahlum, D.D.; Sikov, M.R.; Hess, J.O.; Zwicker, G.M.; Carr, D.B.

    1979-01-01

    The late effects of 239 Pu have been studied after its administration to perinatal, juvenile and adult rats. Adults and weanlings were injected intravenously, newborns intracardially and 19-day foetuses by intravenous injection of the dam. Dose levels were selected to deliver radiation doses of approximately 7, 23, or 70 rads to the femur of all ages during the first 10 days post injection; in general these values were achieved as shown by tissue analysis. Dose rates subsequently diverged, resulting in widely varying cumulative radiation doses for the four age groups. Survival times of rats exposed post-natally were progressively decreased by increasing dose. No decrement in survival was found for those exposed prenatally. Bone tumour incidence was increased by exposure to Pu in all age groups. The younger rats were less sensitive on an administered dose basis, but perhaps more sensitive on the basis of cumulative radiation dose. Prenatally exposed animals, which were cross-fostered to control females, showed a higher incidence of bone tumours than did those that remained with their mother. In the adult the predominant fraction of the bone tumours was found in the extremities with a lesser fraction in the vertebrae, pelvis and other sites. In the two younger age groups the majority of the tumours were in the head with few in the extremities or vertebrae. The incidence of mammary tumours was also elevated in the adult, weanling and prenatal groups by the administration of 239 Pu. (author)

  6. Preparation of additional supplies of 244Pu

    International Nuclear Information System (INIS)

    Bigelow, J.E.; Newman, E.; Alexander, C.W.

    1985-01-01

    In the mid-1970s, gram quantities of the man-made isotope 244 Pu were produced in high purity for basic research as a by-product of a program to prepare gram quantities of 252 Cf. Because 244 Pu is not produced in appreciable quantities in standard power reactor fuel, this nuclide has become extremely useful in the application of isotope dilution mass spectrometry (IDMS), a high-precision analytical technique, to problems of plutonium accountability in support of international safeguards agreements. Although only a small amount (a fraction of a microgram) is needed for each analysis, the present supply of certified nuclear reference standard SRM-996 is expected to last only an additional 3 to 5 years. Three options for producing additional supplies of this rare and valuable material were examined. The options encompassed the production of from 1 to 8.5 g during time spans of from 3 to 10 years. Unit costs ranged from $2300 to $7200 per mg of plutonium of >97% 244 Pu. While the paper concludes that the short-term option can be pursued along with further study of the longer-term options, this should not be regarded as an offer or a commitment on the part of the US Department of Energy (USDOE) to furnish the described material

  7. Preparation of additional supplies of 244Pu

    International Nuclear Information System (INIS)

    Bigelow, J.E.; Newman, E.; Alexander, C.W.

    1985-01-01

    In the mid-1970s, gram quantities of the man-made isotope 244 Pu were produced in high purity for basic research as a by-product of a program to prepare gram quantities of 252 Cf. Because 244 Pu is not produced in appreciable quantities in standard power reactor fuel, this nuclide has become extremely useful in the application of isotope dilution mass spectrometry (IDMS), a high-precision analytical technique, to problems of plutonium accountability in support of international safeguards agreements. Although only a small amount (a fraction of a microgram) is needed for each analysis, the present supply of certified nuclear reference standard SRM-996 is expected to last only an additional 3 to 5 years. Three options for producing additional supplies of this rare and valuable material were examined. The options encompassed the production of from 1 to 8.5 g during time spans of from 3 to 10 years. Unit costs ranged from $2300 to $7200 per mg of plutonium of >97% 244 Pu. While the paper concludes that the short-term option can be pursued along with further study of the longer-term options, this should not be regarded as an offer or a commitment on the part of the U.S. Department of Energy (USDOE) to furnish the described material. (author)

  8. ²³⁹Pu and ²⁴⁰Pu inventories and ²⁴⁰Pu/²³⁹Pu atom ratios in the equatorial Pacific Ocean water column.

    Science.gov (United States)

    Yamada, Masatoshi; Zheng, Jian

    2012-07-15

    The (239+240)Pu concentrations and (240)Pu/(239)Pu atom ratios were determined by alpha spectrometry and inductively coupled plasma mass spectrometry for seawater samples from two stations, one at the equator and the other in the equatorial South Pacific. To better understand the fate of Pu isotopes, this study dealt with the contribution of the close-in fallout Pu from the Pacific Proving Grounds (PPG) in water columns of the Pacific Ocean. The (239)Pu, (240)Pu and (239+240)Pu inventories over the depth interval 0-3000 m at the equator station were 10.4, 8.9 and 19.3 Bq m(-2), respectively. Further, no noticeable difference was observed in (239)Pu, (240)Pu and (239+240)Pu inventories over the depth interval 0-3000 m between the two stations. The total (239+240)Pu inventories were significantly higher than the expected cumulative deposition density of global fallout. Water column (239+240)Pu inventories measured in this study were lower than those reported for comparable stations in the Geochemical Ocean Sections Study, indicating that these inventories have been decreasing at average rates of 0.89 ± 0.07 and 0.16 ± 0.07 Bq m(-2)yr(-1) at the equator and equatorial South Pacific stations, respectively, from 1973 to 1990. The obtained (240)Pu/(239)Pu atom ratios were higher than the mean global fallout ratio of 0.18. These high atom ratios proved the existence of close-in tropospheric fallout Pu from the PPG in the Marshall Islands. The (239+240)Pu inventories originating from the close-in fallout in the entire water column were estimated to be 11.1 Bq m(-2) at the equator station and 7.1 Bq m(-2) at the equatorial South Pacific Ocean station, and the relative percentages of close-in fallout Pu were 40% at the former and 34% at the latter. A significant amount of close-in fallout Pu originating from the PPG has been transported to deep layers below the 1000 m depth in the equatorial Pacific Ocean. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Dosimetry of 239Pu in dogs that inhaled monodisperse aerosols of 239PuO2

    International Nuclear Information System (INIS)

    Guilmette, R.A.; Muggenburg, B.A.; Hahn, F.F.; Mewhinney, J.A.; Seiler, F.A.; Boecker, B.B.; McClellan, R.O.

    1987-01-01

    Existing data from human exposure cases and experimental animal studies on the fate and dosimetry of inhaled insoluble Pu particles are inadequate to provide a comprehensive description and evaluation of the tissues at risk from the alpha radiations of Pu. To improve our knowledge of the dosimetry of inhaled insoluble 239 PuO 2 , this paper describes the uptake and retention of 239 Pu in the tissues of dogs that received single inhalation exposures to monodisperse aerosols of 239 PuO 2 . These data include times through 3 years after exposure. Using analytical functions fitted to each tissue data set, 1100-day radiation doses were calculated for lung, liver, skeleton, kidney, spleen, and tracheobronchial, mediastinal, sternal, hepatic, mandibular, and retropharyngeal lymph nodes. The dosimetry results suggest that the lung and lymph nodes associated with lymphatic drainage of the respiratory tract are the principal sites of alpha irradiation. However, the doses for the different respiratory tract lymph nodes vary by a factor of 2000, suggesting that assuming equivalent doses to respiratory tract lymph nodes is not appropriate. Other tissues receive radiation doses also but at levels one to three orders of magnitude less than the lung. Particle size dependence on uptake and retention was noted for the skeleton, mediastinal lymph nodes, hepatic lymph nodes, retropharyngeal lymph nodes, and mandibular lymph nodes

  10. 242Pu: Preliminary evaluation with consideration of 240Pu, and some sensitivity results

    International Nuclear Information System (INIS)

    Jary, J.; Lagrange, C.; Philis, C.

    1978-01-01

    A preliminary evaluation of 242 Pu nuclear data is presented for the neutron energy range from 10 keV to 20 MeV. The fission cross section is based upon recent experimental measurements on 242 Pu. The remaining cross sections have been calculated using various nuclear models with parameters obtained mainly by both fits on 240 Pu experimental data and general reflexions on the actinides. Particular care has been taken of the direct interactions. The laws of secondary neutron energy spectra and the average number of neutrons produced per fission have been evaluated. The results have been placed in ENDF/BIV format and combined with the low energy region of ENDF/BIV MAT = 1161 data to make complete the evaluation over the whole energy range 10 -5 eV - 20 MeV. Finally, the sensitivities of some of these nuclear data available for reactor calculations are given in terms of the variation of the calculated critical masses

  11. Natural Pu-traces within the continental crust

    International Nuclear Information System (INIS)

    Ganz, M.; Barth, H.; Fuest, M.; Molzahn, D.; Brandt, R.

    1991-01-01

    Pu-traces are observed in the environmental all over the world, 'man made'-Pu as well as 'natural' Pu ( 239 Pu). 239 Pu occurs within a range of about 10 -12 g Pu/g sample in pitchblende. In the FRG, the deep-drilling project 'KTB, Kontinentales Tiefbohrprogramm', was started with the aim to obtain a very deep hole (14 km). We wanted to establish upper concentration limits for plutonium in samples from KTB. For a first investigation, we obtained a 400 g sample of granite from a pre-drill of KTB. Its Pu-concentration was ≤ (4.5 ± 2.5)x10 -16 g 239 Pu/g sample. To compare this result to the Pu-content in geological brines, we obtained a sample from a borehole at the Salton Sea Geothermal field (Southeastern California). In this sample we found an upper concentration limit of (2.1 ± 1.0)x10 -16 g 239 Pu/g sample. (orig.)

  12. Studies of U-Pu-C-Ti compounds

    International Nuclear Information System (INIS)

    Milet, C.

    1967-01-01

    The U-Pu-C-Ti compounds (5 to 20 atoms per cent Ti) have been studied in order to improve some properties of U-Pu-C carbides and to extend the existence field of the (U, Pu) C phase. The Pu/(U+Pu) ratio has been fixed to 15 per cent. All the alloys were elaborated and cast in an arc furnace. A two-phases field (U, Pu) C + Ti C exists which permits to avoid di- and sesqui-carbides and the (U, Pu) phase. An eutectic between (U, Pu) C and Ti C was found around 15 atoms per cent Ti. Practically the whole of the titanium is in Ti C form, titanium solubility in (U, Pu) C being inferior to 1 atom per cent. The most promising alloy are those containing two phases: (U, Pu) C+ Ti C. In comparison with the (U, Pu) C phase, titanium addition does not change very much the thermal expansion coefficients nor the thermal cycling behaviour between 160 and 1000 Celsius degrees which is excellent. On the other hand atmospheric corrosion behaviour is improved; compatibility with stainless steel is better; thermal conductivity, calculated from electrical resistivity K is enhanced: for U(0.85)-Pu(0.15)-C alloy we have K 0.179 W/cm.C at 1000 C and K = 0.187 W/cm.C at 1500 C, for U-Pu-C-Ti (10 atoms % Ti) alloy we have K = 0.193 W/cm.C at 1000 C and K = 0.205 W/cm.C at 1500 C. (author) [fr

  13. Direct reduction of 238PuO2 and 239PuO2 to metal

    International Nuclear Information System (INIS)

    Mullins, L.J.; Foxx, C.L.

    1982-02-01

    The process for reducing 700 g 239 PuO 2 to metal is a standard procedure at Los Alamos National Laboratory. This process is based on research for reducing 200 g 238 PuO 2 to metal. This report describes in detail the experiments and development of the 200-g process. The procedure uses calcium metal as the reducing agent in a molten CaCl 2 solvent system. The process to convert impure plutonia to high-purity metal by oxide reduction followed by electrorefining is also described

  14. Investigation on U - O - Na, Pu - O - Na and U,Pu - O - Na phase diagrams

    International Nuclear Information System (INIS)

    Pillon, S.

    1989-03-01

    The thermochemical interaction between the nuclear fuel (uranium and plutonium mixed oxides) and the sodium has been investigated and particularly the three phase diagrams: U - O - Na; Pu - O - Na; U,Pu - O - Na. High temperature neutron diffraction, microcalorimetry and powder X-ray diffraction were used for the characterization of the compounds synthetized. This study allowed to complete the knowledge about each of these diagrams and to measure some physical and thermal properties on the compounds. The limits on the modelization of the fuel-sodium interaction are discussed from the results of the UO 2 - Na reaction [fr

  15. On the fission probability for 235U, 239Pu and 241Pu

    International Nuclear Information System (INIS)

    Benzi, V.; Maino, G.; Menapace, E.

    1978-01-01

    An evaluation of the GAMMAsub(n)/GAMMAsub(f) ratio for the 236 U, 240 Pu and 242 Pu compound nuclei is carried out. First chance and second chance fission cross sections are estimated from the ''evaporation'' model; particularly, a largely increasing trend was found for the first chance fission cross section above the (n,n'f) process threshold. The GAMMAsub(n)/GAMMAsub(f) ratios for the analyzed nuclei show a bump-like structure, that seems to be in agreement with the theoretical predictions reported in literature

  16. Electrocatalytic performance of Pu(IV)/Pu(III) redox reaction at graphene modified glassy carbon electrode

    International Nuclear Information System (INIS)

    Gupta, Ruma; Gamare, J.S.; Kamat, J.V.; Aggarwal, S.K.

    2014-01-01

    In this paper we explore the analytical perspectives of graphene modified electrode utilising commercially available graphene, which is well characterised, completely free from surfactants and has not been purposely oxidised or treated. We compare and critically contrast the electro-analytical performance of graphene modified glassy carbon electrodes (Gr/GC) with that of unmodified GC electrode towards Pu(IV)/Pu(III) redox reaction, monitoring of which has considerable importance in a plethora of areas where electrochemistry is conveniently and beneficially utilised for determination of nuclear fuels

  17. Liquid chromatographic studies on the behaviour of Pu(III), Pu(IV) and Pu(VI) on a RP stationary phase in presence of α-hydroxyisobutyric acid as a chelating agent

    Energy Technology Data Exchange (ETDEWEB)

    Jaison, P.G.; Kumar, Pranaw; Telmore, Vijay M. [Bhabha Atomic Research Centre, Mumbai (India). Fuel Chemistry Division

    2017-06-01

    Since plutonium possesses multiple oxidation states which can coexist in solution, a method for the identification of these oxidation states is important to understand its chemical processes. Liquid chromatographic studies were carried out to compare the chromatographic behaviour of different oxidation states of Pu in presence of the eluent, α-hydroxyisobutyric acid (HIBA). The three oxidation states of Pu viz. Pu(III), Pu(IV) and Pu(VI) were separated under optimised conditions. It was seen that the presence of the complexing agent influences the equilibrium of Pu(III)/(IV) as well as Pu(IV)/(VI) systems. Pu(III) to Pu(IV) conversion was found to be enhanced by high pH and concentration of HIBA whereas a relatively low pH and high concentration of HIBA promotes the conversion of Pu(VI) to Pu(IV).

  18. Development of an U and Pu recovery process by molten salt electrorefining. Behavior of U and Pu at simultaneous recoveries into liquid cadmium cathodes

    International Nuclear Information System (INIS)

    Uozumi, Koichi; Kato, Tetsuya; Iizuka, Masatoshi; Inoue, Tadashi; Iwai, Takashi; Shirai, Osamu; Arai, Yasuo

    2003-01-01

    In order to study behaviors of U and Pu at simultaneous recoveries into liquid cadmium cathodes (LCCs) in the electrorefining of pyrometallurgical reprocessing, several experiments were conducted to recover U and Pu into LCCs at different U/Pu ratios in the salt phase. The major results were as follows: (1) The weight ratios of U and Pu in 120 g LCCs reached 10 wt.% (the tentative target), with current efficiencies higher than 80 %. (2) Under the conditions of U/Pu ratios in the initial salt phase less than 1/4.3, the amounts of recovered U and Pu were proportional to the passed electric charges, with the separation factors of U to Pu (= (U/Pu ration in the recovered product)/(U/Pu ratio in the salt)) between 1.2 and 2.0. (3) On the other hand, under the condition of U/Pu ratio in the initial salt phase at 1/1.73, only U was recovered into the LCC after the saturation of LCC with U and Pu. Accordingly, there will be a threshold in the U/Pu ratio of the salt phase for the simultaneous recovery of U and Pu. (4) Am showed a similar behavior to Pu. The separation factors of Am to Pu (=(AM/Pu ratio in the recovered product)/(Am/Pu ratio in the salt)) was 0.78, which means that Am is co-recovered with Pu into LCC. (author)

  19. Characterization of a Pu-bearing zirconolite-rich synroc

    International Nuclear Information System (INIS)

    Buck, E.C.; Ebbinghaus, B.; Bakel, A.J.; Bates, J.K.

    1996-01-01

    A titanate-based ceramic waste form, rich in phases structurally related to zirconolite (CaZrTi 2 O 7 ), is being developed as a possible method for immobilizing excess plutonium from dismantled nuclear weapons. As part of this program, Lawrence Livermore National Laboratory (LLNL) produced several ceramics that were then characterized at Argonne National Laboratory (ANL). The plutonium- loaded ceramic was found to contain a Pu-Gd zirconolite phase but also contained plutonium titanates, Gd-polymignyte, and a series of other phases. In addition, much of the Pu was remained as PuO 2- x . The Pu oxidation state in the zirconolite was determined to be mainly Pu 4+ , although some Pu 3+ was believed to be present

  20. Studies in the solubility of Pu(III) oxalate

    Energy Technology Data Exchange (ETDEWEB)

    Hasilkar, S P; Khedekar, N B; Chander, K; Jadhav, V; Jain, H C [Bhabha Atomic Research Centre, Bombay (India). Fuel Reprocessing Div.

    1994-11-01

    Studies have been carried out on the solubility of Pu(III) oxalate by precipitation of Pu(III) oxalate from varying concentrations of HNO[sub 3]/HCl (0.5-2.0M) solutions and also by equilibrating freshly prepared Pu(III) oxalate with solutions containing varying concentrations of HNO[sub 3]/HCl, oxalic acid and ascorbic acid. Pu(III) solutions in HNO[sub 3] and HCl media were prepared by reduction of Pu(IV) with ascorbic acid. 0.01-0.10M ascorbic acid concentration in the aqueous solution was maintained as holding reductant. The solubility of Pu(III) oxalate was found to be a minimum in 0.5M-1M HNO[sub 3]/HCl solutions containing 0.05M ascorbic acid and 0.2M excess oxalic acid in the supernatant. (author) 6 refs.; 6 tabs.

  1. A 244Pu spike reference material CBNM IRM-042A

    International Nuclear Information System (INIS)

    Verbruggen, A.; Gallet, M.; Hendrickx, F.; Bievre, P. de

    1991-01-01

    An highly enriched 244 Pu isotopic reference material (CBNM IRM-042a) has been prepared and certified for 244 Pu isotope concentration. The certified value of (2.257 7 ± 0.004 4).10 18 atoms 242 Pu.kg -1 of solution has been established by isotope dilution mass spectrometry. The plutonium isotopic composition has been determined by thermal ionization mass spectrometry and calibration of these measurements by means of synthetic 242 Pu/ 239 Pu mixtures. The isotopic reference material is supplied in a sealed glass ampoule containing approximately 10 g of a 5M nitric acid solution at an approximate concentration of 1 μg Pu per g solution. This isotopic reference material is part of a systematic CBNM programme to supply spike isotopic reference materials of various isotopes at different concentrations

  2. Unsafe Coulomb excitation of $^{240-244}Pu$

    CERN Document Server

    Wiedenhöver, I; Hackman, L; Ahmad, I; Greene, J P; Amro, H; Carpenter, M P; Nisius, D T; Reiter, P; Lauritsen, T; Lister, C J; Khoo, T L; Siem, S; Cizewski, J A; Seweryniak, D; Uusitalo, J; Macchiavelli, A O; Chowdhury, P; Seabury, E H; Cline, D; Wu, C Y

    1999-01-01

    The high spin states of /sup 240/Pu and /sup 244/Pu have been investigated with GAMMASPHERE at ATLAS, using Coulomb excitation with a /sup 208/Pb beam at energies above the Coulomb barrier. Data on a transfer channel leading to /sup 242/Pu were obtained as well. In the case of /sup 244/Pu, the yrast band was extended to 34h(cross), revealing the completed pi i/sub 13/2/ alignment, a "first" for actinide nuclei. The yrast sequence of /sup 242/Pu was also extended to higher spin and a similar backbend was delineated. In contrast, while the ground state band of /sup 240/Pu was measured up to the highest rotational frequencies ever reported in the actinide region (~300 keV), no sign of particle alignment was observed. (11 refs).

  3. Anomalous atomic volume of alpha-Pu

    DEFF Research Database (Denmark)

    Kollar, J.; Vitos, Levente; Skriver, Hans Lomholt

    1997-01-01

    We have performed full charge-density calculations for the equilibrium atomic volumes of the alpha-phase light actinide metals using the local density approximation (LDA) and the generalized gradient approximation (GGA). The average deviation between the experimental and the GGA atomic radii is 1.......3%. The comparison between the LDA and GGA results show that the anomalously large atomic volume of alpha-Pu relative to alpha-Np can be ascribed to exchange-correlation effects connected with the presence of low coordinated sites in the structure where the f electrons are close to the onset of localization...

  4. Study of U - Pu - Fe alloys (Masurca critical experiment)

    International Nuclear Information System (INIS)

    Barthelemy, P.; Boucher, R.

    1965-01-01

    Three compositions have been studied: 73.5 U - 25 Pu - 1.5 Fe (weight %) 74 U - 25 Pu - 1 Fe 74.5 U - 25 Pu - 0.5 Fe Elaboration and Casting are easy. After two weeks in air 74.5 U - 25 Pu - 0.5 Fe alloys are reduced in powder. As-cast alloys containing 1 and 1,5% Fe are kept undamaged during several months. A rapid oxidisation of the alloys is however observed when the samples undergo the phase transformation (at 595 deg. C and 590 deg. C respectively). Ignition tests in the presence of air show that the oxidisation starts at about 250 deg. C and that the reaction does not spread. Ignition is not observed during heating from 20 to 660 deg. C. The transformation temperature, the melting temperature and the thermal expansion coefficients have been determined by dilatometry. Below the transformation temperature, the principal phases are U-Pu zeta and (U, Pu) 6 Fe. Thermal conductibility, Young modulus, density and heat of fusion have been measured. Compatibility tests show that between U-Pu-Fe and stainless steel a phase of (U, Pu) 6 Fe type is formed. The 74 U - 25 Pu - 1% Fe alloy seems to behave better than 73.5 U - 25 Pu - 1.5% Fe alloy because the (U, Pu) 6 Fe layer is two or three times smaller. Finally, the thermal stability has been studied with the 74 U - 25 Pu - 1% Fe alloy. A dilatometric anomaly (very weak expansion) occurs when the sample is heated above transformation temperature and cooled. But there is no anomaly by thermal cycling from 50 deg. C to 400 deg. C and there is no deterioration of alloys by heat treatments at 100 deg. C, 200 deg. C, 300 deg. C during 5 months under vacuum. (authors) [fr

  5. Metal-carbide multilayers for molten Pu containment

    International Nuclear Information System (INIS)

    Summers, T.S.E.; Curtis, P.G.; Juntz, R.S.; Krueger, R.L.

    1991-12-01

    Multilayers composed of nine or ten alternating layers of Ta or W and TaC were studied for the feasibility of their use in containing molten plutonium (Pu) at 1200 degrees C. Single layers of W and TaC were also investigated. A two-source electron beam evaporation process was developed to deposit these coatings onto the inside surface of hemispherical Ta cups about 38 mm in diameter. Pu testing was done by melting Pu in the coated hemispherical cups and holding them under vacuum at 1200 degrees C for two hours. Metallographic examination and microprobe analysis of cross sections showed that Pu had penetrated to the Ta substrate in all cases to some extent. Full penetration to the outer surface of the Ta substrate, however, occurred in only a few of the samples. The fact that full penetration occurred in any of the samples suggests that it would have occurred in uncoated Ta under these testing conditions which in turn suggests that the multilayer coatings do afford some protection against Pu attack. The TaC used for these specimens was wet by Pu under these testing conditions, and following testing, Pu was found uniformly distributed throughout the carbide layers which appeared to be rather porous. Pu was seen in the W and Ta layers only when exposed directly to molten Pu during testing or near defects suggesting that Pu penetrated the multilayers at defects in the coating and traveled parallel to the layers along the carbide layers. These results indicate that the use of alternating metal and ceramic layers for Pu containment should be possible through the use of nonporous ceramic that is not wet by molten Pu and defect-free films

  6. Calculation on maximum accumulation of Pu-239 and Pu-241 from aqueous homogeneous reactor

    International Nuclear Information System (INIS)

    Ikhlas H Siregar; Frida Agung R; Suharyana; Azizul Khakim; Dahman Siregar

    2016-01-01

    Calculations on maximum accumulation of Pu-239 and Pu-241 using MCNPX computer code with UO_2(NO_3)_2 fuel solution enriched by 19.75% operating at temperature 80°C have been conducted. AHR design was simulated with cylindrical core having diameter of 63.4 cm and 122 cm high. From this geometry we found the reactor was critical with density 108 gr U/L of UO_2(NO_3)_2 solution. The result showed that multiplication factor (k_e_f_f) of AHR was 1.05284. Then the burn up calculations were done for various time intervals from 5 days until 285 years to analyze the result. From calculation, it was found out that the saturated concentration of Pu-239 was reached after 40-50 years of operation, producing 1.23 x 102 gr and the activity 7.645 Ci. While for operate time of AHR to produce Pu-241 should under 80 years with mass 21.7 gr and the activity 2.247 x 103 Ci. The accumulations of both isotopes are considered to be small, having low potential for misusing them for producing nuclear weapon. (author)

  7. PuLP/XtraPuLP : Partitioning Tools for Extreme-Scale Graphs

    Energy Technology Data Exchange (ETDEWEB)

    2017-09-21

    PuLP/XtraPulp is software for partitioning graphs from several real-world problems. Graphs occur in several places in real world from road networks, social networks and scientific simulations. For efficient parallel processing these graphs have to be partitioned (split) with respect to metrics such as computation and communication costs. Our software allows such partitioning for massive graphs.

  8. Pu and Am determination in the environment method development

    International Nuclear Information System (INIS)

    Afonin, M.; Simonoff, M.; Donard, O.; Michel, H.; Ardisson, G.

    2002-01-01

    A few articles were published in the recent years regarding the application of ICP MS HR to the determination of ultratrace Pu in the environment. Si removal was not applied in recent publications. It is well known from marine biology that some microorganisms use Si derivatives in their metabolism. This implies that important amounts of Pu will not be dissolved and instead will rest in the solid residue. In our work we chose a combination of methods from EML-300 Handbook: Pu-02-RC Plutonium in Soil Samples, Pu-03-RC Plutonium in Soil Residue - Total Dissolution Method, Pu-11-RC Plutonium Purification - Ion Exchange Technique, Pu-12-RC Plutonium and/or Americium in Soil or Sediments. A high resolution inductively coupled plasma mass spectrometric method was developed for the determination of Am and the 240 Pu/ 239 Pu isotope ratio. The total plutonium concentrations ( 239+240 Pu) measured in environmental samples by this method were in good agreement with recommended data obtained from alpha-spectrometry. A reduction in the time of analysis over 33% was achieved

  9. Analytical description of transfer of Pu-239 in undisturbed soil

    Energy Technology Data Exchange (ETDEWEB)

    Tianshan, Ren; Linsalata, P; Cohen, N

    1986-04-01

    The paper reports on an analytical model for describing the horizontal and down-ward transfer of /sup 239/Pu in undisturbed soil based on observed data. The model has been developed to predict how the depth distribution of /sup 239/Pu in soil would change with time. This information is essential for estimation of the quantities of /sup 239/Pu that have entered surface water body via erosion and runoff processes and for estimation of the long-term impact of /sup 239/Pu isice the commencement of nuclear fallout deposition.

  10. Effect of equilibration time on Pu desorption from goethite

    International Nuclear Information System (INIS)

    Wong, Jennifer C.; Powell, Brian A.; Zavarin, Mavrik; Begg, James D.; Kersting, Annie B.

    2015-01-01

    It has been suggested that strongly sorbing ions such as plutonium may become irreversibly bound to mineral surfaces over time which has implications for near- and far-field transport of Pu. Batch adsorption-desorption data were collected as a function of time and pH to study the surface stability of Pu on goethite. Pu(IV) was adsorbed to goethite over the pH range 4.2 to 6.6 for different periods of time (1, 6, 15, 34 and 116 d). Following adsorption, Pu was leached from the mineral surface with desferrioxamine B (DFOB), a complexant capable of effectively competing with the goethite surface for Pu. The amount of Pu desorbed from the goethite was found to vary as a function of the adsorption equilibration time, with less Pu removed from the goethite following longer adsorption periods. This effect was most pronounced at low pH. Logarithmic desorption distribution ratios for each adsorption equilibration time were fit to a pH-dependent model. Model slopes decreased between 1 and 116 d adsorption time, indicating that overall Pu(IV) surface stability on goethite surfaces becomes less dependent on pH with greater adsorption equilibration time. The combination of adsorption and desorption kinetic data suggest that non-redox aging processes affect Pu sorption behavior on goethite.

  11. HANFORD Pu-238 DRUM INTEGRITY ASSESSMENT

    International Nuclear Information System (INIS)

    CANNELL, G.R.

    2004-01-01

    Hanford is presently retrieving contact-handled, transuranic (CH-TRU) waste drums from the site's Low-Level Burial Grounds (LLBG) for processing and disposition. A subgroup of these drums (12 total), referred to as Pu-238 drums, has some unique characteristics that may impact the current drum handling and processing activities. These characteristics include content, shielding, thermal, pressurization and criticality issues. An effort to evaluate these characteristics, for the purpose of developing a specific plan for safe retrieval of the Pu-238 drums, is underway. In addition to the above evaluation, the following integrity assessment of the inner container material and/or confinement properties, with primary emphasis on the Source Capsule (primary confinement barrier) and Shipping Container has been performed. Assessment included review of the inner container materials and the potential impact the service history may have had on material and/or confinement properties. Several environmental degradation mechanisms were considered with the objective of answering the following question: Is it likely the container material and/or confinement properties have been significantly altered as a result of service history?

  12. U, Pu, and Am nuclear signatures of the Thule hydrogen bomb debris

    DEFF Research Database (Denmark)

    Eriksson, Mats; Lindahl, Patric; Roos, Per

    2008-01-01

    ). In the five hot particles examined, the measured uranium atomic ratio was U-235/U-238 = 1.02 +/- 0.16 and the Pu-isotopic ratios were as follows: Pu-240/Pu-239 0.0551 +/- 0.0008 (atom ratio), Pu-238/Pu239+240 = 0.0161 +/- 0.0005 (activity ratio), Pu-241/Pu239+240 = 0.87 +/- 0.12 (activity ratio), and Am-241...... than one Pu source involved in the accident, confirming earlier studies. The Pu-238/Pu239+240 activity ratio and the Pu-240/Pu-239 atomic ratio were divided into at least two Pu-isotopic ratio groups. For both Pu-isotopic ratios, one ratio group had identical ratios as the five hot particles described...... above and for the other groups the Pu isotopic ratios were lower (Pu-238/Pu239+240 activity ratio similar to 0.01 and the Pu-240/Pu-239 atomic ratio 0.03). On the studied particles we observed that the U/Pu ratio decreased as a function of the time these particles were present in the sediment. We...

  13. Solubility of reactor fuels in the mouse lung with respect to their U/Pu and 238Pu/239Pu ratios

    International Nuclear Information System (INIS)

    Talbot, R.J.; Baker, S.T.

    1989-01-01

    The studies reported were designed to assess the comparative in vivo solubilities of a range of plutonium containing reactor fuels. To simulate these fuels, mixed U/Pu oxides were prepared and calcined at 1600 0 C. A plutonium content of 3% w/w was chosen as typical of water-cooled reactor fuel. Higher concentrations of plutonium (10, 20 and 30%) were included to simulate fast reactor fuel. As it is known that 238 PuO 2 , with high specific activity, is translocated more rapidly from lung than 239 PuO 2 , the effect of isotopic composition of plutonium in simulated reactor fuels was also investigated. For this purpose, both the water-cooled and fast-reactor fuels were prepared with plutonium containing 2% of 238 Pu by weight. The resulting oxides had about 6 times the specific activity of those prepared with 239 Pu. Groups of mice were killed at 1, 3, 6, 12 and 18 months after inhaling aerosols of the simulated reactor fuels. After 3 months, measurements of Pu retention in the lung showed no marked differences between materials. After 6 months, measurements of plutonium deposited in the liver and skeleton showed that mixed U/Pu oxides were more soluble in vivo than 239 PuO 2 . Their solubility was inversely related to their plutonium content. The addition of 238 Pu to the plutonium resulted in enhanced translocation of plutonium from the lung, in the cases of water-cooled reactor fuel by a factor of two. (author)

  14. 242Pu as tracer for simultaneous determination of 237Np and 239,240Pu in environmental samples

    DEFF Research Database (Denmark)

    Chen, Q.J.; Dahlgaard, H.; Nielsen, S.P.

    2002-01-01

    A procedure has been developed using Pu-242 as tracer for simultaneous determination of Np-237 and Pu-239,Pu-240 in environmental samples. The validity of the method has been demonstrated by ICPMS and alpha-spectroscopy for up to 10 gram soil and sediment, seawater up to 200 litres. The paper...... from Np and Pu) R-before/R-after = 1.004 +/- 3.3% (S.D n = 20) and 1 litre seawater R-before/R-after = 1.019+/-1.9% (S.D., n = 12). Results from the intercomparison samples LAEA-135, LAEA-381 and from environmental samples are presented....... describes a suitable chemical procedure for Np and Pu including a quantitative pre-concentration of neptunium and plutonium, preparation of Np4+ and Pu4+, NP(NO3)(6)(2-) and Pu(NO3)(6)(2-), The ratio of Np-237/Pu-242 (or Np-237/Pu-239) before and after the procedure has been determined using 10 g soil (free...

  15. Review of the thermodynamics of the U--C, Pu--C, and U--Pu--C systems

    International Nuclear Information System (INIS)

    Tetenbaum, M.; Sheth, A.; Olson, W.

    1975-06-01

    Thermodynamic properties such as enthalpy, heat capacity, entropy, heat and free energy of formation, and vaporization behavior are presented for the U--C, Pu--C, and U--Pu--C systems. These properties are of interest to scientists and engineers involved in the expanding field of advanced fuel LMFBR systems. The information on these systems has been derived largely from the discussions of the IAEA Panel on the assessment of thermodynamic properties of the U--C, Pu--C, and U--Pu--C systems. (U.S.)

  16. Evaluation of fission cross sections and covariances for {sup 233}U, {sup 235}U, {sup 238}U, {sup 239}Pu, {sup 240}Pu, and {sup 241}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Toshihiko [Kyushu Univ., Fukuoka (Japan); Matsunobu, Hiroyuki [Data Engineering, Inc. (Japan); Murata, Toru [AITEL Corporation, Tokyo (JP)] [and others

    2000-02-01

    A simultaneous evaluation code SOK (Simultaneous evaluation on KALMAN) has been developed, which is a least-squares fitting program to absolute and relative measurements. The SOK code was employed to evaluate the fission cross sections of {sup 233}U, {sup 235}U, {sup 238}U, {sup 239}Pu, {sup 240}Pu, and {sup 241}Pu for the evaluated nuclear data library JENDL-3.3. Procedures of the simultaneous evaluation and the experimental database of the fission cross sections are described. The fission cross sections obtained were compared with evaluated values given in JENDL-3.2 and ENDF/B-VI. (author)

  17. Evaluation of fission cross sections and covariances for 233U, 235U, 238U, 239Pu, 240Pu, and 241Pu

    International Nuclear Information System (INIS)

    Kawano, Toshihiko; Matsunobu, Hiroyuki; Murata, Toru

    2000-02-01

    A simultaneous evaluation code SOK (Simultaneous evaluation on KALMAN) has been developed, which is a least-squares fitting program to absolute and relative measurements. The SOK code was employed to evaluate the fission cross sections of 233 U, 235 U, 238 U, 239 Pu, 240 Pu, and 241 Pu for the evaluated nuclear data library JENDL-3.3. Procedures of the simultaneous evaluation and the experimental database of the fission cross sections are described. The fission cross sections obtained were compared with evaluated values given in JENDL-3.2 and ENDF/B-VI. (author)

  18. Data Evaluation of Actinide Cross Sections: 238Pu, 237Pu, and 236Pu

    Energy Technology Data Exchange (ETDEWEB)

    Guaglioni, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Jurgenson, E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Descalle, M. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Thompson, I. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ormand, E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Escher, J. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Younes, W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mattoon, C. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Beck, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Burke, J. T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bailey, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-10-04

    This report documents the recent evaluation of the 236Pu, 237Pu, and 238Pu cross section sets. Nuclear data evaluation is the fundamental interface that takes measured nuclear cross section data and turns them into a continuous curve that 1) is consistent with other measurements and nuclear reaction theory/models, and 2) is required by down-stream users. All experiments that generate nuclear data need to include an evaluation step for their data to be broadly useful to the end users.

  19. α spectrometry on thick sources. Application to Pu dosing in U-Pu alloys with a low Pu content

    International Nuclear Information System (INIS)

    Guery, Marcel

    1969-06-01

    After having noticed that alpha spectrometry of thick sources has been not much studied, the author reports the application of this type of alpha spectrometry to a problem of plutonium dosing in uranium-plutonium alloys with low plutonium content. Four measurement and test campaigns, each being few month long, have been performed. During the first three ones, the best measurement conditions have been determined, the necessary apparatus has been acquired, and data compilation has been elaborated. This report addresses the last campaign during which exploitable results have been obtained. After some generalities about alpha rays from thick sources, the author reports a detailed examination of measurements made on U-Pu alloys, and of corrections to be made, notably those due to the Am-241 content, to stacking and to oxidation. The method appears to be very sensitive, with a precision better than 1 per cent. Improvements seem possible [fr

  20. PU.1 silencing leads to terminal differentiation of erythroleukemia cells

    International Nuclear Information System (INIS)

    Atar, Orna; Levi, Ben-Zion

    2005-01-01

    The transcription factor PU.1 plays a central role in development and differentiation of hematopoietic cells. Evidence from PU.1 knockout mice indicates a pivotal role for PU.1 in myeloid lineage and B-lymphocyte development. In addition, PU.1 is a key player in the development of Friend erythroleukemia disease, which is characterized by proliferation and differentiation arrest of proerythrocytes. To study the role of PU.1 in erythroleukemia, we have used murine erythroleukemia cells, isolated from Friend virus-infected mice. Expression of PU.1 small interfering RNA in these cells led to significant inhibition of PU.1 levels. This was accompanied by inhibition of proliferation and restoration in the ability of the proerythroblastic cells to produce hemoglobin, i.e., reversion of the leukemic phenotype. The data suggest that overexpression of PU.1 gene is the immediate cause for maintaining the leukemic phenotype of the disease by retaining the self-renewal capacity of transformed erythroblastic cells and by blocking the terminal differentiation program towards erythrocytes

  1. Procedure for plutonium determination using Pu(VI) spectra

    International Nuclear Information System (INIS)

    Walker, L.F.; Temer, D.J.; Jackson, D.D.

    1996-01-01

    This document describes a simple spectrophotometric method for determining total plutonium in nitric acid solutions based on the spectrum of Pu(VI). Plutonium samples in nitric acid are oxidized to Pu(VI) with Ce(IV) and the net absorbance at the 830 nm peak is measured

  2. Ceramic grade (U,Pu)O2 powder fabrication

    International Nuclear Information System (INIS)

    Cristallini, O.A.; Villegas de Maroto, Marina; De Pino, J.I.; Osuna, H.A.

    1980-01-01

    Ceramic grade UO 2 powder was obtained by the homogeneous precipitation method. This procedure was afterwards applied to the fabrication of ceramic grade (U,Pu)O 2 powders, and mixed oxide powders with Pu content ranging from 0.7 to 16% were obtained. The obtainment of mixed ceramic oxides as well as the recuperation of fabrication scraps were developed in three steps: 1)study of the process of homogeneous precipitation of ammonium diuranate (ADU); 2) co-precipitation of ADU/PuO 2 .H 2 O for Pu concentrations of 0.6 and 6.8; 3) the thermal conditioning to mixed oxide (U,Pu)O 2 powders. The experimental procedure involves the following steps: preparation of the PuO 2 (NO 3 ) 4 solution; co-precipitation of the PuO 2 (NO 3 ) 2 solution with an UO 2 (NO 3 ) 2 solution; filtration and drying of the precipitate, thermal treatment and finally, mixing, pressing and sintering of the (U,Pu)O 2 and Nukem UO 2 powder with a 0. of zinc stearate. Different controls were made by means of physical, chemical and ceramographic tests. This method can be used for the fabrication of fast reactor fuels or, previous mechanical dispersion in UO 2 powder, for the fabrication of thermal reactors fuels. (M.E.L.) [es

  3. Structure and potential energy function for Pu22+ ion

    International Nuclear Information System (INIS)

    Li Quan; Huang Hui; Li Daohua

    2003-01-01

    The theoretical study on Pu 2 2+ using density functional method shows that the molecular ion is metastable. Ground electronic state is 13 Σ g for Pu 2 2+ , the analytic potential energy function is in well agreement with the Z-W function, and the force constants and spectroscopic data have been worked out for the first time

  4. Np Analysis in IAT-Samples Containing <10 Microgram Pu

    International Nuclear Information System (INIS)

    Ludwig, R.; Raab, W.; Dashdondog, J.; Balsley, S.

    2008-01-01

    A method for the determination of neptunium to plutonium in safeguards samples containing less than 10 microgram Pu is presented. The chemical treatment and the optimized measurement conditions for gamma spectrometry are reported. This method is based on thermal ionization mass spectrometry (TIMS) after chemical treatment and separation and was validated with mixtures of U, Pu and Np certified reference materials and using the 237 Np standard addition method, followed by separation of the waste fraction and gamma spectrometric analysis. The highest sensitivity, precision and accuracy in the determination of the Np:Pu ratio at microgram levels of Pu is achieved by evaluating 241 Pu and 233 Pa after measuring the adsorbent with a well-type gamma detector 3 weeks after chemical treatment. The repeatability of determining the Np:Pu ratio is estimated to be 5%, the maximum uncertainty as determined from comparing the 4 measurement modes is within ± 10% for samples containing 3 μg Pu, while being within ± 20% for 0.4 μg Pu. (authors)

  5. Savannah River Laboratory monthly report: 238Pu fuel form processes

    International Nuclear Information System (INIS)

    1976-01-01

    Progress in the Savannah River 238 Pu Fuel Form Program is discussed. Goals of the Savannah River Laboratory (SRL) program are to provide technical support for the transfer of the 238 Pu fuel form fabrication operations from Mound Laboratory to new facilities being built at the Savannah River Plant (SRP), to provide the technical basis for 238 Pu scrap recovery at SRP, and to assist in sustaining plant operations. During the period it was found that the density of hot-pressed 238 PuO 2 pellets decreased as the particle size of ball-milled powder decreased;the surface area of calcined 238 PuO 2 powder increased with increasing precipitation temperature and may be related to the variation in ball-milling response observed among different H Area B-Line batches; calcined PuO 2 produced by Pu(III) reverse-strike precipitation was directly fabricated into a pellet without ball milling, slugging, or sharding. The pellet had good appearance with acceptable density and dimensional stability, and heat transfer measurements and calculations showed that the use of hollow aluminum sleeves in the plutonium fuel fabrication (PuFF) storage vault reduced the temperature of shipping cans to 170 0 C and will reduce the temperature at the center of pure plutonium oxide (PPO) spheres to 580 0 C

  6. Np Analysis in IAT-Samples Containing <10 Microgram Pu

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, R.; Raab, W.; Dashdondog, J.; Balsley, S. [IAEA, Safeguards Analytical Laboratory, Wagramer Str. 5, P.O. Box 100, A-1400 Vienna (Austria)

    2008-07-01

    A method for the determination of neptunium to plutonium in safeguards samples containing less than 10 microgram Pu is presented. The chemical treatment and the optimized measurement conditions for gamma spectrometry are reported. This method is based on thermal ionization mass spectrometry (TIMS) after chemical treatment and separation and was validated with mixtures of U, Pu and Np certified reference materials and using the {sup 237}Np standard addition method, followed by separation of the waste fraction and gamma spectrometric analysis. The highest sensitivity, precision and accuracy in the determination of the Np:Pu ratio at microgram levels of Pu is achieved by evaluating {sup 241}Pu and {sup 233}Pa after measuring the adsorbent with a well-type gamma detector 3 weeks after chemical treatment. The repeatability of determining the Np:Pu ratio is estimated to be 5%, the maximum uncertainty as determined from comparing the 4 measurement modes is within {+-} 10% for samples containing 3 {mu}g Pu, while being within {+-} 20% for 0.4 {mu}g Pu. (authors)

  7. Preparation, microstructures, and properties of PuO2

    International Nuclear Information System (INIS)

    Bickford, D.F.; Rankin, D.T.; Smith, P.K.

    1976-01-01

    PuO 2 pellets with controlled microstructures were fabricated to meet operational requirements for packaged heat sources. Size distributions, morphologies (forms and structures), and packing densities were measured on calcined and milled powders, slugged compacts, and presintered granules. These variables influence microstructure, porosity distribution, and fracture behavior of hot-pressed and sintered PuO 2

  8. Nuclear characteristics of Pu fueled LWR and cross section sensitivities

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Toshikazu [Osaka Univ., Suita (Japan). Faculty of Engineering

    1998-03-01

    The present status of Pu utilization to thermal reactors in Japan, nuclear characteristics and topics and cross section sensitivities for analysis of Pu fueled thermal reactors are described. As topics we will discuss the spatial self-shielding effect on the Doppler reactivity effect and the cross section sensitivities with the JENDL-3.1 and 3.2 libraries. (author)

  9. Modification of analytical method for measurement of 239Pu, 240Pu and 241Am in sediment and sea water

    International Nuclear Information System (INIS)

    Syarbaini; Tarigan, C.; Rustam, M.F.

    1997-01-01

    Modification of analytical method for measurement of 239 Pu, 240 Pu and 241 Am in sediment and sea water have been conducted. This study is to develop a method for separation of 239 Pu, 240 Pu and 241 Am from 100-300 g of sediment and 100-200 l of sea water samples. Most of the methods described in the literature are to separation of '2 39 Pu, '2 40 Pu and 241 Am from 20-50 g of sediment and 30-100 l of sea water samples. By this method, 239,240 Pu and 241 Am were concentrated using the coprecipitation of CaC 2 O 4 and Fe (OH) 3 . Plutonium-242 and Curium-244 were used as tracer to determine chemical recovery. The result of analysis of some sediment samples showed that the chemical recoveries were respectively obtained in the range of 59.7 to 72.6% with average of 66.2 % for 242 Pu and 72.0 % to 85.5 % with average 78.8 % for 244 Cm. Analysis of some sea water samples were obtained in the range of 67 % to 78 % with average 73.9 % for 242 Pu and 74.0 % to 90.0 % with average 84.2 % for '2 42 Cm. This method was tested by the IAEA marine sediment, the result was excellent agreement with the IAEA certified sediment. It could be suggested that the developed analytical method is suitable to analyze the low level 239 Pu, 240 Pu and 241 Am in sediment and sea water samples (author)

  10. Sorption of Pu onto some kinds of clay

    International Nuclear Information System (INIS)

    Jia Haihong; Si Gaohua; Liu Wei; Yu Jing

    2010-01-01

    There are rich clay mines holding in one area, so it's necessary to know about these clays' sorption capacity to Pu, for building radioactive waste repository in the area. Distribution coefficients of Pu onto different clays were acquired in static method, with the result about 104. The size of clay is different, but the result of Kds is near. In addition, it's estimated how far Pu moves in the most rapid speed in the clay based on these Kids', disregarding the influence of Pu-colloid. In a word, as a kind of backfilling material clays in the area can effectively prevent Pu from moving to environment, and when designing the backfilling layer, it's not necessary to catch clays through NO.200 sieve, if only considering the influence of Kd. (authors)

  11. 239Pu standards for quantitative neutron-induced autoradiography

    International Nuclear Information System (INIS)

    Smith, J.M.; Atherton, D.R.; Wronski, T.J.; Jee, W.S.S.

    1977-01-01

    The present study deals with the preparation of 239 Pu standards for neutron bone tissue autoradiography and the calibration of these standards with respect to uranium reference standards. Known concentrations of 239 Pu were prepared in methyl methacrylate and Bioplastic casting resin bars. Wafers sawed from these bars served as standards. Solid state nuclear tract detectors (Lexan polycarbonate) were used to record fission fragment tracks after the standards were exposed to a thermal neutron flux. The original bars were found to contain a uniform distribution of 239 Pu. To confirm the concentration of 239 Pu in the wafers, the induced track density from the 239 Pu standards was compared with that from uranium reference standards. The average fission fragment detection efficiency for all of the standards was 0.51

  12. The Kuwano peculiar object (PU Vulpeculae)

    International Nuclear Information System (INIS)

    Belyakina, T.S.; Gershberg, R.E.; Efimov, Yu.S.; Krasnobabtsev, V.I.; Pavlenko, E.P.; Petrov, P.P.; Chuvaev, K.K.; Shenavrin, V.I.

    1982-01-01

    U, B, V, J, H, K photometry, polarimetry and spectroscopy of this peculiar object was made from August 1979 to December 1980 and the observations are briefly discussed. The authors consider PU Vul to be binary with a late M giant and a component of probably low luminosity. The latter flared in 1979, and the former also changed a little. From the photometric, spectroscopic and polarimetric data they estimate E(B-V) <= 0.4 and locate the star at 5-7 kpc from the sun and 0.7-1.0 kpc from the galactic plane. The photometric behaviour, duplicity, and nature of the components are similar to those of novae and symbiotic stars, but no evidence for an ejected envelope is seen. (Auth.)

  13. Photonuclear data evaluation of 239Pu

    International Nuclear Information System (INIS)

    Raskinyte, I.; Dupont, E.; Ridikas, D.

    2006-01-01

    This document presents cross-section calculations up to 130 MeV for Pu 239 using the Talys-0.64 code. The photoabsorption process is described by the giant dipole resonance and quasi-deuteron mechanisms. Preequilibrium particle emission is treated with the classical exciton model. At equilibrium, the compound nucleus decay channels are handled within the Hauser-Feshbach statistical model. Neutron transmission coefficients are calculated with a double humped parabolic model. A few sensitive nuclear parameters were fine-tuned to better reproduce the experimental data available for (γ,n), (γ,2n) and (γ,f) partial cross-sections. In addition, the nuclear models provide predictions of the emitted neutron energy and angular distributions. (A.C.)

  14. The evaluation of the mass distribution data for 238U, 239Pu and 242Pu fission

    International Nuclear Information System (INIS)

    Liu Tingjin

    2002-01-01

    The mass distribution data for 238 U at E n =1.5, 5.5, 8.3, 11.3, 14.9, 22.0, 27.5, 50.0, 99.5, 160.0 MeV, E p =20.0, 60.0 MeV 239 Pu at E n =0.17, 7.9, 14.5 MeV and 242 Pu at E n =15.1 MeV were evaluated and recommended based on the main available experimental data up to now. The experimental data were make necessary corrections and their errors were also made necessary adjustments. The problems concerned were discussed

  15. Distinguishing Pu Metal from Pu Oxide and Determining alpha-ratio using Fast Neutron Counting

    Energy Technology Data Exchange (ETDEWEB)

    Verbeke, J. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chapline, G. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Nakae, L. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Prasad, M. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sheets, S. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Snyderman, N. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-01-07

    We describe a new method for determining the ratio of the rate of (α, n) source neutrons to the rate of spontaneous fission neutrons, the so called α-ratio. This method is made possible by fast neutron counting with liquid scintillator detectors, which can determine the shape of the fast neutron spectrum. The method utilizes the spectral difference between fission spectrum neutrons from Pu metal and the spectrum of (α, n) neutrons from PuO2. Our method is a generalization of the Cifarelli-Hage method for determining keff for fissile assemblies, and also simultaneously determines keff along with the α-ratio.

  16. Pu-238 Supply Program Project Execution Plan

    International Nuclear Information System (INIS)

    Wham, Robert M.; Martin, Sherman

    2012-01-01

    This Pu-238 Supply Program Project Execution Plan (PEP) summarizes critical information and processes necessary to manage the program. The PEP is the primary agreement regarding planning and objectives between The Department of Energy Office of Nuclear Energy (DOE NE-75), Oak Ridge National Laboratory Site Office (OSO) and the Oak Ridge National Laboratory (ORNL). The acquisition executive (AE) will approve the PEP. The PEP is a living document that will be reviewed and revised periodically until the project is complete. The purpose of the project is to reestablish the capability to produce plutonium-238 (Pu-238) domestically. This capability consists primarily of procedures, processes, and design information, not capital assets. As such, the project is not subject to the requirements of DOE O 413.3B, but it will be managed using the project management principles and best practices defined there. It is likely that some capital asset will need to be acquired to complete tasks within the project. As these are identified, project controls and related processes will be updated as necessary. Because the project at its initiation was envisioned to require significant capital assets, Critical Decision 0 (CD-0) was conducted in accordance with DOE O 413.3B, and the mission need was approved on December 9, 2003, by William Magwood IV, director of the Office of Nuclear Energy (NE), Science and Technology, DOE. No date was provided for project start-up at that time. This PEP is consistent with the strategy described in the June 2010 report to Congress, Start-up Plan for Plutonium-238 Production for Radioisotope Power Systems.

  17. Base case Pu-nitrate to Pu-oxide conversion plant

    International Nuclear Information System (INIS)

    1978-10-01

    This paper explains that the plutonium recovered in the course of reprocessing spent fuel is obtained in the form of plutonium nitrate, whereas PuO 2 is required for the fabrication of fuel rods. The reference conversion plant described in the paper converts plutonium nitrate into plutonium dioxide powder by precipitation with oxalic acid followed by calcination. The paper also describes the main features of the safety, maintenance and safeguards philosophy used in its design

  18. Internal Corrosion Analysis of Model 9975 Packaging Containing Pu or PuO2 During Shipping and Storage

    International Nuclear Information System (INIS)

    Vormelker, P.

    1999-01-01

    The Materials Consultation Group of SRTC has completed an internal corrosion analysis of the Model 9975 packaging assembly containing either Pu or PuO2 for storage in K Reactor under ambient conditions for a period of 12 years. The 12-year storage period includes two years for shipping and up to ten years for storage

  19. Determination of isotope fractionation effect using a double spike (242Pu+240Pu) during the mass spectrometric analysis of plutonium

    International Nuclear Information System (INIS)

    Chitambar, S.A.; Parab, A.R.; Khodade, P.S.; Jain, H.C.

    1986-01-01

    Isotope fractionation effect during the mass spectrometric analysis of plutonium has been investigated using a double spike ( 242 Pu+ 240 Pu) and the determination of concentration of plutonium in dissolver solution of irradiated fuel is reported. (author). 6 refs., 2 tables

  20. Pu(V) as the stable form of oxidized plutonium in natural waters

    International Nuclear Information System (INIS)

    Orlandini, K.A.; Penrose, W.R.; Nelson, D.M.

    1986-01-01

    This work presents analytical evidence supporting the proposition that Pu(V) is the sole or predominant form of oxidized plutonium in natural waters. Two independent methods, the selective adsorption of Pu(VI) by silica gel, and the somewhat less selective coprecipitation of Pu(V) with calcium carbonate, were developed to separate Pu(V) from Pu(VI). Measurements of ambient plutonium in several natural waters by these methods found only Pu(V). In laboratory tracer studies, Pu(VI) was shown to be highly unstable in dilute bicarbonate solution and in Lake Michigan water, reducing in first-order fashion to Pu(V). (orig.)

  1. Interception and retention of 238Pu deposition by orange trees

    International Nuclear Information System (INIS)

    Pinder, J.E. III; Adriano, D.C.; Ciravolo, T.G.; Doswell, A.C.; Yehling, D.M.

    1987-01-01

    Radioisotope thermoelectric generators (RTG) transform the heat produced during the alpha decay of 238 Pu into electrical energy for use by deep-space probes, such as the Voyager spacecraft, which have returned images and other data from Jupiter, Saturn and Uranus. Future missions involving RTGs may be launched aboard the space shuttle, and there is a remote possibility that an explosion of liquid-hydrogen and liquid-oxygen fuel could rupture the RTGs and disperse 238 Pu into the atmosphere over central Florida. Research was performed to determine the potential transport to man of atmospherically dispersed Pu via contaminated orange fruits. The results indicate that the major contamination of oranges would result from the interception and retention of 238 Pu deposition by fruits. The resulting surface contamination could enter human food chains through transfer to internal tissues during peeling or in the reconstituted juices and flavorings made from orange skins. The interception of 238 Pu deposition by fruits is especially important because the results indicate no measurable loss of Pu from fruit surfaces through time or with washing. Approximately 1% of the 238 Pu deposited onto an orange grove would be harvested in the year following deposition

  2. Elastic properties of gamma-Pu by resonant ultrasound spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Migliori, Albert [Los Alamos National Laboratory; Betts, J [Los Alamos National Laboratory; Trugman, A [Los Alamos National Laboratory; Mielke, C H [Los Alamos National Laboratory; Mitchell, J N [Los Alamos National Laboratory; Ramos, M [Los Alamos National Laboratory; Stroe, I [WORXESTER, MA

    2009-01-01

    Despite intense experimental and theoretical work on Pu, there is still little understanding of the strange properties of this metal. We used resonant ultrasound spectroscopy method to investigate the elastic properties of pure polycrystalline Pu at high temperatures. Shear and longitudinal elastic moduli of the {gamma}-phase of Pu were determined simultaneously and the bulk modulus was computed from them. A smooth linear and large decrease of all elastic moduli with increasing temperature was observed. We calculated the Poisson ratio and found that it increases from 0.242 at 519K to 0.252 at 571K.

  3. Risk estimates for lung tumours from inhaled 239PuO2, 238PuO2, and 239Pu(NO3)4 in beagle dogs

    International Nuclear Information System (INIS)

    Dagle, G.E.; Park, J.F.; Gilbert, E.S.; Weller, R.E.

    1989-01-01

    Lung cancer risks are being studied in beagle dogs given single exposures to aerosols of 239 PuO 2 , 238 PuO 2 , or 239 Pu(NO 3 ) 4 . A major objective of these studies is to examine the risk of lung cancer relative to the specific activity of the radionuclide, rate of dose accumulation due to differences in solubilities of the radionuclides, and the presence of competing risk from extrapulmonary lesions. Dose-response relationships were studied for the three groups of dogs, with analyses specifically designed to evaluate differences in response. Based on estimated cumulative dose to the lung, risks were found to differ significantly among the radionuclides; they were highest for 239 Pu(NO 3 ) 4 and lowest for 238 PuO 2 . A model in which the risk was assumed to be a pure quadratic function of dose fitted the data much better than a pure linear model. Currently, all three groups of dogs can be compared only to 10 years after exposure. However, it is apparent that the average cumulative dose to the lung may not be an adequate predictor of lung cancer risk for different isotopic and physicochemical forms of plutonium. (author)

  4. A COMPARISON OF (PuU)C AND (PuU)O$sub 2$ FUELED FAST BREEDER REACTORS

    Energy Technology Data Exchange (ETDEWEB)

    Kazi, A. Halim; Rosen, Stanley

    1963-11-15

    BS>A conceptual evaluation is presented of a (PuU)C 500Mw(e) reactor which uses a moderate power generation of 40 kw/ft and a maximum fuel temperature of 2900 deg F, well below the 4500 deg F melting point of Pu/sub 0.2/U/sub 0.8/C. The principal design characteristics and fuel cycle costs are tabulated together with those of a (PuU)O/sub 2/ design of equal power. The comparison shows that the carbide core has significant economic and safety advantages over the oxide core. (D.L.C.)

  5. Biosorption of 239Pu by immobilized sargassum fusiforme

    International Nuclear Information System (INIS)

    Liang Zhirong; Chen Qi; Wu Yusheng

    2009-01-01

    Sargassum fusiforme was immobilized with calcium alginates and its biosorption property to 239 Pu was studied by batch and column methods. Biosorption equilibrium time of immobilized Sargassum fusiforme biosorbent to 239 Pu is 120 min and biosorption efficiency is over 99.2% when the initial concentration of 239 Pu is 21.5 kBq/L and pH is 2.5-5.0. After five times repetition biosorption-desorption cycles biosorption efficiency is still over 98.0% when the velocity of flow is 2 ml/min in column experiment. Immobilized Sargassum fusiforme biosorbent is better to 239 Pu due to its better chemical stability, mechanical strength, lower cost, high biosorption efficiency and repeated biosorption-desorption cycles. (authors)

  6. Relative 238Pu content of bone and bone marrow

    International Nuclear Information System (INIS)

    McClanahan, B.J.

    1979-01-01

    Selected bones from a dog that inhaled 238 PuO 2 were subjected to ultrasonic cell disruption to separate the marrow elements from bone, in order to determine the plutonium content of the two components of the skeleton

  7. Irradiation of blood by 238Pu alpha particles

    International Nuclear Information System (INIS)

    Hungate, F.P.; Riemath, W.F.; Culver, G.G.; Gillis, M.F.; Ragan, H.A.

    1976-01-01

    A developmental 238 Pu blood irradiator produced no evidence of lymphopenia in a dog. Irradiation continued for a year at an estimated rate of about 100 rads/day, but this dosimetry is highly uncertain

  8. Determination of Pu and U by ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Muramatsu, Y.; Yoshida, S. [National Inst. of Radiological Sciences, Chiba (Japan)

    2002-06-01

    In order to understand the distribution and behaviour of long-lived radionuclides in the terrestrial environment, we have developed analytical methods for {sup 238}U, {sup 232}Th and {sup 239},{sup 240}Pu and determined them in several environmental samples. ICP-MS was applied to the analyses. Concentrations of {sup 238}U and {sup 232}Th were determined in variety of soils, plants and environmental waters. The mean concentration of U and Th in 77 soils, collected several parts of Japan, were 2.3 and 7.0 ppm (dry wt). Red and yellow soils, which are mainly found in western Japan, have high concentrations of Th, suggesting the contribution from granitic rocks. Higher concentration of U in agricultural soils than forest soils suggested the possible accumulation of this element from phosphate fertilizer. The soil-to-plant transfer factors (concentration ratios between plants and soils) of U and Th were estimated from the analytical results of these nuclides in soils and in several crops. The factors for U were about 0.0005 in leaf vegetables, 0.0002 in root vegetables, 0.0001 in potatoes and 0.00001 in rice (polished). For Th, the factors were about 0.0005 in leaf vegetables, 0.0008 in root vegetables, 0.0005 in potatoes and 0.00003 in rice (polished). For the analysis of plutonium, chromatographic resin, Dowex 1x8, was examined for their applicability in the separation of Pu from the matrix elements. Sufficient decontamination factors (10{sup 4}-10{sup 5}) for many matrix elements including U, which interferes in the detection of mass 239, were obtained in both resins. Analytical results of {sup 239+240}Pu in standard reference materials (IAEA-135, -SOIL-6, -368 and -134) indicated that the accuracy of this method was satisfactory. Data on the {sup 240}Pu/{sup 239}Pu atom ratios in these reference materials, which are rare in the literature, were also obtained. Soil samples from the Marshall Islands showed a large variation of the {sup 240}Pu/{sup 239}Pu atom ratios

  9. Spatial and temporal distribution of Pu in the Northwest Pacific Ocean using modern coral archives.

    Science.gov (United States)

    Lindahl, Patric; Andersen, Morten B; Keith-Roach, Miranda; Worsfold, Paul; Hyeong, Kiseong; Choi, Min-Seok; Lee, Sang-Hoon

    2012-04-01

    Historical (239)Pu activity concentrations and (240)Pu/(239)Pu atom ratios were determined in skeletons of dated modern corals collected from three locations (Chuuk Lagoon, Ishigaki Island and Iki Island) to identify spatial and temporal variations in Pu inputs to the Northwest Pacific Ocean. The main Pu source in the Northwest Pacific is fallout from atmospheric nuclear weapons testing which consists of global fallout and close-in fallout from the former US Pacific Proving Grounds (PPG) in the Marshall Islands. PPG close-in fallout dominated the Pu input in the 1950s, as was observed with higher (240)Pu/(239)Pu atom ratios (>0.30) at the Ishigaki site. Specific fallout Pu contamination from the Nagasaki atomic bomb and the Ivy Mike thermonuclear detonation at the PPG were identified at Ishigaki Island from the (240)Pu/(239)Pu atom ratios of 0.07 and 0.46, respectively. During the 1960s and 1970s, global fallout was the major Pu source to the Northwest Pacific with over 60% contribution to the total Pu. After the cessation of the atmospheric nuclear tests, the PPG again dominated the Pu input due to the continuous transport of remobilised Pu from the Marshall Islands along the North Equatorial Current and the subsequent Kuroshio Current. The Pu contributions from the PPG in recent coral bands (1984 onwards) varied over time with average estimated PPG contributions between 54% and 72% depending on location. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Transfer of 239Pu to mouse fetoplacental tissues

    International Nuclear Information System (INIS)

    Kubota, Yoshihisa; Sato, Hiroshi; Koshimoto, Chihiro; Takahashi, Sentaro

    1993-01-01

    Cross-placental transfer of 239 Pu from the mother to fetus was studied in C3H mice. The activity of 239 Pu in the conceptus was measured 24 hrs after the intravenous injection of 239 Pu citrate on days 10.5 to 16.5 of gestation. More 239 Pu was transferred to the conceptus when the plutonium was administered in the later stages of gestation; 0.12% of the injected dose per conceptus on day 10.5 and 1.3% on day 16.5. In all the gestational stages examined, the yolk sac and decidua contained more than 89% of the total activity distributed in the conceptus. The concentration of 239 Pu in the yolk sac was about two orders of magnitude greater than that in the fetus. The 239 Pu concentration in the maternal liver decreased with the gestational stage. In the early gestational stages the concentration in the maternal liver was greater than that in the yolk sac; but, this relationship was reversed in the later stages. (author)

  11. Radiative capture on $^{242}$Pu for MOX fuel reactors

    CERN Multimedia

    The use of MOX fuel (mixed-oxide fuel made of UO$_{2}$ and PuO$_{2}$) in nuclear reactors allows substituting a large fraction of the enriched Uranium by Plutonium reprocessed from spent fuel. Indeed around 66% of the plutonium from spent fuel is made of $^{239}$Pu and $^{241}$Pu, which are fissile in thermal reactors. A typical reactor of this type uses a fuel with 7% reprocessed Pu and 93% depleted U, thus profiting from both the spent fuel and the remaining $^{238}$U following the $^{235}$U enrichment. With the use of such new fuel compositions rich in Pu the better knowledge of the capture and fission cross sections of the Pu isotopes becomes very important. This is clearly stated in the recent OECD NEA’s “High Priority Request List” and in the WPEC-26 “Uncertainty and target accuracy assessment for innovative systems using recent covariance data evaluations” report. In particular, a new series of cross section evaluations have been recently carried out jointly by the European (JEFF) and United ...

  12. Unsafe Coulomb excitation of 240-244Pu

    International Nuclear Information System (INIS)

    Ahmad, I.; Amro, H.; Carpenter, M. P.; Chowdhury, P.; Cizewski, J.; Cline, D.; Greene, J. P.; Hackman, G.; Janssens, R. V. F.; Khoo, T. L.; Lauritsen, T.; Lister, C. J.; Macchiavelli, A. O.; Nisius, D. T.; Reiter, P.; Seabury, E. H.; Seweryniak, D.; Siem, S.; Uusitalo, J.; Wiedenhoever, I.; Wu, C. Y.

    1999-01-01

    The high spin states of 240 Pu and 244 Pu have been investigated with GAMMASPHERE at ATLAS, using Coulomb excitation with a 208 Pb beam at energies above the Coulomb barrier. Data on a transfer channel leading to 242 Pu were obtained as well. In the case of 244 Pu, the yrast band was extended to 34h b ar revealing the completed πi 13/2 alignment, a ''first'' for actinide nuclei. The yrast sequence of 242 Pu was also extended to higher spin and a similar backbend was delineated. In contrast, while the ground state band of 240 Pu was measured up to the highest rotational frequencies ever reported in the actinide region (approximately300 keV), no sign of particle alignment was observed. In this case, several observable such as the large B(E1)/B(E2) branching ratios in the negative parity band, and the vanishing energy staggering between the negative and positive parity bands suggest that the strength of octupole correlations increases with rotational frequency. These stronger correlations may well be responsible for delaying or suppressing the πi 13/2 particle alignment

  13. Performance of cladding on MOX fuel with low 240Pu/239Pu ratio

    International Nuclear Information System (INIS)

    McCoy, K.; Blanpain, P.; Morris, R.

    2015-01-01

    The U.S. Department of Energy has decided to dispose of a portion of its surplus plutonium by reconstituting it into mixed oxide (MOX) fuel and irradiating it in commercial power reactors. As part of fuel qualification, four lead assemblies were manufactured and irradiated to a maximum fuel rod average burnup of 47.3 MWd/kg heavy metal. This was the world's first commercial irradiation of MOX fuel with a 240 Pu/ 239 Pu ratio less than 0.10. Five fuel rods with varying burnups and plutonium contents were selected from one of the assemblies and shipped to Oak Ridge National Laboratory for hot cell examination. This paper discusses the results of those examinations with emphasis on cladding performance. Exams relevant to the cladding included visual and eddy current exams, profilometry, microscopy, hydrogen analysis, gallium analysis, and mechanical testing. There was no discernible effect of the type of MOX fuel on the performance of the cladding. (authors)

  14. Assessment of 238Pu and 239+240Pu, in marine sediments of the oceans Atlantic and Pacific of Guatemala

    International Nuclear Information System (INIS)

    Mendez Ochaita, L.

    2000-01-01

    In this investigation samples of marine sediments were taken from 14 places representatives of the oceans coast of Guatemala. For the assesment of 238 Pu and 239+240 Pu in sediments a radiochemical method was used to mineralize sediments and by ionic interchange it was separated from other elements, after that an electrodeposition of plutonium was made in metallic discs. The radioactivity of plutonium was measured by alpha spectrometry system and the alpha spectrums were obtained. The levels of plutonium are not higher than other countries that shown contamination. The contamination of isotope of 239+240 Pu is higher than 238 Pu and the contamination by two isotopes of plutonium is higher in the Atlantic than the Pacific ocean

  15. Aspects of 238Pu production in the experimental fast reactor JOYO

    International Nuclear Information System (INIS)

    Osaka, Masahiko; Koyama, Shin-ichi; Tanaka, Kenya; Itoh, Masahiko; Saito, Masaki

    2005-01-01

    Experimental determination of 238 Pu in 237 Np samples irradiated in the experimental fast reactor JOYO was done as part of the demonstration of 238 Pu production from 237 Np in fast reactors within the framework of the protected Pu production project, which aims at reinforcement of proliferation resistance of Pu by increasing the 238 Pu isotopic ratio. 238 Pu production amount in the irradiated 237 Np samples was determined by a radioanalytical technique. Aspects of 238 Pu production were examined on the basis of the present radioanalysis. The 238 Pu production amount depends on the neutron spectrum which can range from that of a typical fast reactor to a nearly epi-thermal spectrum. It is concluded that the fast reactor has not only high potential for use in protected Pu production, but also as an incinerator for excess Pu

  16. Estimation of uncertainties in resonance parameters of {sup 56}Fe, {sup 239}Pu, {sup 240}Pu and {sup 238}U

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Tsuneo; Shibata, Keiichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-05-01

    Uncertainties have been estimated for the resonance parameters of {sup 56}Fe, {sup 239}Pu, {sup 240}Pu and {sup 238}U contained in JENDL-3.2. Errors of the parameters were determined from the measurements which the evaluation was based on. The estimated errors have been compiled in the MF32 of the ENDF format. The numerical results are given in tables. (author)

  17. Cation interdiffusion in the UO2 - (U, Pu)O2 and UO2 - PuO2 systems

    International Nuclear Information System (INIS)

    Leme, D.G.

    1985-01-01

    The interdiffusion of U and Pu ions in UO sub(2 +- x) - (U sub(0,83) Pu sub(0,17))O sub(2 + - x) and UO sub(2 + - x) -PuO sub(2 - x) sintered pellets and UO sub(2 +- x) -(U sub(0,82) Pu sub(0,18))O sub(2 + - x) single crystals has been studied as a function of the oxygen potential ΔG sup(-) (O 2 ) or the stoichiometric ratio O/M. The diffusion profiles of UO 2 /(U,Pu)O 2 and UO 2 /PuO 2 couples of different O/M ratios have been measured using high resolution α-spectrometer and microprobe. Thermal annealing of the specimens was performed in controlled atmospheres using either CO-CO 2 gas mixtures for constant O/M ratios or purified argon. The interdiffusion profiles have been analysed by means of the Boltzmann-Matano and Hall methods. The interdiffusion coefficient D sus(approx.) increases with increasing Pu content in sintered pellets (up to 17 wt. %PuO 2 ) showing a strong dependence of D sup(approx.) on the O/M ratio. The micropobe results show that the interdiffusion along grain boundaries is the main diffusion mechanism in the pellets. Experiments have also been carried out in single cristals to measure just the bulk-interdiffusion and avoiding effects due to grain boundaries. A marked dependence of D sup(approx.) on O/M ratio or on oxygen potential ΔG sup(-) (O 2 ), similar to the dependence already reported for self diffusion by means of radioactive tracers, has also been observed. (Author) [pt

  18. Chemical properties of the predicted 32-electron systems PuSn{sub 12} and PuPb{sub 12}

    Energy Technology Data Exchange (ETDEWEB)

    Dognon, J.P. [CEA Saclay, UMR 3299 CEA/CNRS SIS2M, laboratoire de chimie de coordination des elements f, 91 - Gif-sur-Yvette (France); Clavaguera, C. [Laboratoire des mecanismes reactionnels, departement de chimie, Ecole polytechnique, CNRS, 91 - Palaiseau (France); Pyykko, P. [Department of Chemistry, University of Helsinki (Finland)

    2010-06-15

    The electronic structures, as well as spectroscopic and thermodynamic properties of the title PuM{sub 12} clusters, are considered at the density functional theory level. In both cases, a Pu{sup 2+} ion is encapsulated in an icosahedral, stanna- or plumbaspherene M{sub 12}{sup 2-} cage. As suggested before for M=Pb, both systems are reported to follow a 32-electron principle for the central atom. (authors)

  19. Vertical profiles of 239(240)Pu, 238Pu and 241Am in some peculiar Italian mosses

    International Nuclear Information System (INIS)

    Testa, C.; Desideri, D.; Guerra, F.; Meli, M.A.; Roselli, C.; Jia, G.; Degetto, S.

    2000-01-01

    During the last two years the Urbino University and the Padua ICTIMA CNR were working on a special radioecological program having the aim to study the Pu and Am retention behaviour in different species of mosses growing in two Italian regions (Urbino, Central Italy, 450 m a.s.l. and Alps region, Northern Italy, 1500 m a.s.l.). 239,240 Pu, 238 Pu and 241 Am were separated and determined by extraction chromatography, electroplating and alpha spectrometry; 242 Pu and 243 Am were used as the yield tracers. The paper summarizes the results dealing with the vertical profiles of the radionuclides in three different species of mosses. Several 1-2 cm high sections were obtained and dated by 210 Pb determination. Typical concentration peaks for Pu and Am were found for very old moss species ('Sphagnum Compactum' and 'Sphagnum Nemoreum') at a depth corresponding to the early 1960's which is the period characterized by the maximum nuclear weapon tests. In more recent moss species ('Neckeria Crispa') no peak was observed and the regression curves showed that Am is more mobile than Pu. (author)

  20. Use of combined alpha-spectrometry and fission track analysis for the determination of 240Pu/239Pu ratios in human tissue

    International Nuclear Information System (INIS)

    Love, S.F.; Filby, R.H.; Glover, S.E.; Stuit, D.B.; Kathren, R.L.

    1998-01-01

    Plutonium and other actinides were determined in human autopsy tissues of occupationally exposed workers who were registrants of the United States Transuranium and Uranium Registries (USTUR). In this study, Pu was purified and isolated from Am, U and Th, after drying and wet-ashing of the tissues, and the addition of 238 Pu as a radiotracer. After electrodeposition onto vanadium planchets, the 239+240 Pu activity was determined by alpha-spectrometry. A fission track method was developed to determine 239 Pu in the presence of 238 Pu and 240 Pu, using Lexan TM polycarbonate detectors. Combining the two techniques allowed the determination of the 240 Pu/ 239 Pu activity and atom ratios. Data from selected USTUR cases are presented. (author)

  1. Reaction of plutonium with water kinetic and equilibrium behavior of binary and ternary phases in the Pu + O + H system

    International Nuclear Information System (INIS)

    Haschke, J.M.; Hodges, A.E. III; Bixby, G.E.; Lucas, R.L.

    1983-01-01

    The kinetic and equilibrium behavior of the Pu + O + H system has been studied by measuring the production of hydrogen gas formed by a sequence of hydrolysis reactions. The kinetic dependence of the Pu + H 2 O reaction on salt concentration and temperature has been defined. The metal is quantitatively converted to a fine black powder which has been identified as plutonium monoxide monohydride, PuOH. Other hydrolysis products formed in aqueous media include a second oxide hydride, Pu 7 O 9 H 3 , and the oxides Pu 2 O 3 , Pu 7 O 12 , Pu 9 O 16 , Pu 10 O 18 , Pu 12 O 22 , and PuO 2 . Thermal decomposition products of PuOH include Pu 2 O 2 H and PuO. A tentative phase diagram for Pu + O + H is presented and structural relationships of the oxide hydrides and oxides are discussed. 10 figures, 5 tables

  2. Investigation of the oxidation states of Pu isotopes in a hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M.H. [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, P. O. Box 105, Yuseong, Daejeon 305-353 (Korea, Republic of)], E-mail: mhlee@kaeri.re.kr; Kim, J.Y.; Kim, W.H.; Jung, E.C.; Jee, K.Y. [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, P. O. Box 105, Yuseong, Daejeon 305-353 (Korea, Republic of)

    2008-12-15

    The characteristics of the oxidation states of Pu in a hydrochloric acid solution were investigated and the results were applied to a separating of Pu isotopes from IAEA reference soils. The oxidation states of Pu(III) and Pu(IV) were prepared by adding hydroxylamine hydrochloride and sodium nitrite to a Pu stock solution, respectively. Also, the oxidation state of Pu(VI) was adjusted with concentrated HNO{sub 3} and HClO{sub 4}. The stability of the various oxidation states of plutonium in a HCl solution with elapsed time after preparation were found to be in the following order: Pu(III){approx}Pu(VI)>Pu(IV)>Pu(V). The chemical recoveries of Pu(IV) in a 9 M HCl solution with an anion exchange resin were similar to those of Pu(VI). This method for the determination of Pu isotopes with an anion exchange resin in a 9 M HCl medium was applied to IAEA reference soils where the activity concentrations of {sup 239,240}Pu and {sup 238}Pu in IAEA-375 and IAEA-326 were consistent with the reference values reported by the IAEA.

  3. The Transport of Close-In Fallout Plutonium in the Northwest Pacific Ocean: Tracing the Water Mass Movement Using {sup 240}Pu/{sup 239}Pu Atom Ratio

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang-Han [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Hong, Gi-Hoon; Suk, Moon-Sik [Korea Ocean Research and Development Institute, Seoul (Korea, Republic of); Gastaud, J. [International Atomic Energy Agency, Marine Environment Laboratory (Monaco); La Rosa, J. [National Institute of Standards and Technology, Ionizing Radiation Division, Gaithersburg, Maryland (United States); Kim, Chul-Soo [Environmental Laboratories, International Atomic Energy Agency, Seibersdorf (Austria); Wyse, E. [New Brunswick Laboratory Argonne, IL (United States); Povinec, P. P. [Comenius University, Faculty of Mathematics and Physics, Bratislava (Slovakia)

    2013-07-15

    {sup 240}Pu/{sup 239}Pu atom ratios in seawater and surface sediment collected from the northwest (NW) Pacific Ocean from 1992 to 1997 were determined using ICP-sector field mass spectrometry (ICP-MS). In whole water columns, the atom ratios of {sup 240}Pu/{sup 239}Pu were higher than the global fallout ratio (0.18). It is noted that the atom ratios of {sup 240}Pu/2{sup 39}Pu in the seawater increase with depth. Such elevated {sup 240}Pu/{sup 239}Pu atom ratios indicate that the close-in fallout plutonium isotopes originating from the Pacific Proving Grounds (PPGs) due to the U.S. tests are prevailing in the seawater in the NW Pacific Ocean. However, the {sup 240}Pu/{sup 239}Pu atom ratios in the surface sediment from the NW Pacific Ocean varied with the sampling locations. As a consequence, this study will provide the information that the water mass along with the current plays a key role in driving the distribution of Pu and in transporting Pu from the PPGs to the far eastern marginal sea in the NW Pacific Ocean. (author)

  4. Archiver ce qui aurait pu avoir lieu

    Directory of Open Access Journals (Sweden)

    Stefanie Baumann

    2009-12-01

    Full Text Available L’Atlas Group, un projet de l’artiste libanais Walid Raad, est « dédié à la recherche et la compilation de documents sur l’histoire contemporaine libanaise. L’Atlas Group produit, localise, conserve et étudie des documents visuels, sonores, textuels et autres, qui mettent en lumière l’histoire actuelle du Liban. »Ce projet est ainsi présenté comme une fondation qui génère des archives historiques et qui collecte des traces relevant de la guerre au Liban afin de les mettre à disposition aux chercheurs. Mais, les matériaux sont produits par l’artiste : l’archive est imaginaire, les documents et récits sont inventés, ainsi que le Docteur Fakhouhi, le personnage principal, présenté comme étant « le plus renommé des historiens au Liban ». Le spectateur se trouve alors devant un scénario très étrange dans lequel sont détournées les notions de document (qui peut désormais être aussi bien trouvé que produit et d’histoire (car les situations décrites sont considérées comme « ayant très bien pu avoir eu lieu », l’Atlas Group  les traite comme de véritables événement historiques et qui déplace, mine de rien, tout un dispositif. Au sein de ce projet, la frontière entre fiction et documentaire est complètement estompée : le geste de l’artiste (qui, lui, se présente comme une institution, un « Groupe », interroge ainsi le statut même d’auteur vise à la déplacer pour poser des questions relatives aux représentations possibles de l’histoire, aux personnes aptes à se charger de son écriture et à l’opération historiographique.

  5. Estimation of Ni63, Pu241, Pu242 and Am243 from Co60, Pu239, and Cm244 activities in groundwater samples

    International Nuclear Information System (INIS)

    Holcomb, H.P.

    1993-01-01

    The Part B Permit for F ampersand H Seepage Basins calls for analysis of several constituents of concern in groundwater monitoring wells. Four of these analytes are the radionuclides Ni 63 , Pu 241 , Pu 242 , and Am 243 . These are currently not being analyzed due to their very difficult, tedious analytical schemes coupled with their relatively low activity values. This report demonstrates how the activity value for Ni 63 , a week beta emitter, can be estimated from that of Co 60 , an easily detectable, high-energy gamma emitter. Similarly, estimates of Pu 241 , a beta emitter, and the alpha-emitting Pu 242 can be made from the activity value of the more easily detected Pu 239 . Am 243 can be estimated from the activity of Cm 244 , which is easier to detect because of a shorter half-life (higher specific activity) and the emission of higher energy alpha particles. These correlations are made under very specific parameters in order to ensure the validity of this approach. Therefore, assumptions must be established setting ground rules for establishing these activity relationships. Bases for these assumptions are explained and/or referenced. Their degree of uncertainty limits the accuracy of the data so that the term ''estimate'' is used. Such soundly-based, conservative estimates for these four rads can provide a tool for evaluating any hazards from their presence over the next several years. Hopefully, during this time, sufficient advances will be made in their radiochemical analyses and in counting techniques so that in the future, their activities may be quantitatively determined more easily and also more cost effectively

  6. Fractionation of 137Cs and Pu in natural peatland

    International Nuclear Information System (INIS)

    Mihalík, Ján; Bartusková, Miluše; Hölgye, Zoltán; Ježková, Tereza; Henych, Ondřej

    2014-01-01

    High Cs-137 concentrations in plants growing on peatland inspired us to investigate the quantity of its bioavailable fraction in natural peat. Our investigation aims to: a) estimate the quantity of bioavailable Cs-137 and Pu present in peat, b) verify the similarity of Cs-137 and K-40 behaviours, and c) perform a quantification of Cs-137 and Pu transfer from peat to plants. We analysed the vertical distribution of Cs-137 and Pu isotopes in the peat and their concentrations in plants growing on these places. Bioavailability of radionuclides was investigated by sequential extraction. Sequential analyses revealed that it was the upper layer which contained the majority of Cs-137 in an available form while deeper layers retained Cs-137 in immobile fractions. We can conclude that 18% of all Cs-137 in the peat is still bioavailable. Despite of the low quantity of bioavailable fraction of Cs-137 its transfer factor reached extremely high values. In the case of Pu, 64% of its total amount was associated with fulvic/humic acids which resulted in the high transfer factor from peat to plants. 27 years after the Chernobyl nuclear accident, the significant part of radionuclides deposited in peatland is still bioavailable. - Highlights: • Decrease of exchangeable 137 Cs and its increase in residual fraction with depth. • High 137 Cs transfer factor contrary to its low quantity in bioavailable fractions. • Fulvic/humic acids are a more effective carrier for Pu than for Cs

  7. LEAD SLOWING DOWN SPECTROSCOPY FOR DIRECT Pu MASS MEASUREMENTS

    International Nuclear Information System (INIS)

    Ressler, Jennifer J.; Smith, Leon E.; Anderson, Kevin K.

    2008-01-01

    The direct measurement of Pu in previously irradiated fuel assemblies is a recognized need in the international safeguards community. A suitable technology could support more timely and independent material control and accounting (MC and A) measurements at nuclear fuel storage areas, the head-end of reprocessing facilities, and at the product-end of recycled fuel fabrication. Lead slowing down spectroscopy (LSDS) may be a viable solution for directly measuring not only the mass of 239Pu in fuel assemblies, but also the masses of other fissile isotopes such as 235U and 241Pu. To assess the potential viability of LSDS, an LSDS spectrometer was modeled in MCNP5 and 'virtual assays' of nominal PWR assemblies ranging from 0 to 60 GWd/MTU burnup were completed. Signal extraction methods, including the incorporation of nonlinear fitting to account for self-shielding effects in strong resonance regions, are described. Quantitative estimates of Pu uncertainty are given for simplistic and more realistic fuel isotopic inventories calculated using ORIGEN. A discussion of additional signal-perturbing effects that will be addressed in future work, and potential signal extraction approaches that could improve Pu mass uncertainties, are also discussed

  8. Measurements Conducted on an Unknown Object Labeled Pu-239

    International Nuclear Information System (INIS)

    Hoteling, Nathan

    2013-01-01

    Measurements were carried out on 12 November 2013 to determine whether Pu-239 was present on an object discovered in a plastic bag with label ''Pu-239 6 uCi''. Following initial survey measurements to verify that the object was not leaking or contaminated, spectra were collected with a High Purity Germanium (HPGe) detector with object positioned in two different configurations. Analysis of the spectra did not yield any direct evidence of Pu-239. From the measured spectra, minimum detectable activity (MDA) was determined to be approximately 2 uCi for the gamma ray measurements. Although there was no direct evidence of Pu-239, a peak at 60 keV characteristic of Am-241 decay was observed. Since it is very likely that Am-241 would be present in aged plutonium samples, this was interpreted as indirect evidence for the presence of plutonium on the object. Analysis of this peak led to an estimated Pu-239 activity of 0.02-0.04 uCi, or <1x10 -6 grams.

  9. Vertical distribution of 241Pu in the southern Baltic Sea sediments

    International Nuclear Information System (INIS)

    Strumińska-Parulska, Dagmara I.

    2014-01-01

    Highlights: • The unique study on 241 Pu in sediments from the southern Baltic Sea was presented. • 241 Pu was determined using alpha spectrometry by indirect method. • The biggest amount of 241 Pu existed in the surface layers of all analyzed sediments. • The highest 241 Pu amount comes from the Chernobyl accident. - Abstract: The vertical distribution of plutonium 241 Pu in marine sediments can assist in determining the deposition history and sedimentation process of analyzed regions. In addition, 241 Pu/ 239+240 Pu activity ratio could be used as a sensitive fingerprint for radioactive source identification. The present preliminary studies on vertical distribution of 241 Pu in sediments from four regions of the southern Baltic Sea are presented. The distribution of 241 Pu was not uniform and depended on sediment geomorphology and depth as well as location. The highest concentrations of plutonium were found in the surface layers of all analyzed sediments and originated from the Chernobyl accident

  10. ZZ WPPR-FR-MOX/BNCMK, Benchmark on Pu Burner Fast Reactor

    International Nuclear Information System (INIS)

    Garnier, J.C.; Ikegami, T.

    1993-01-01

    Description of program or function: In order to intercompare the characteristics of the different reactors considered for Pu recycling, in terms of neutron economy, minor actinide production, uranium content versus Pu burning, the NSC Working Party on Physics of Plutonium Recycling (WPPR) is setting up several benchmark studies. They cover in particular the case of the evolution of the Pu quality and Pu fissile content for Pu recycling in PWRs; the void coefficient in PWRs partly fuelled with MOX versus Pu content; the physics characteristics of non-standard fast reactors with breeding ratios around 0.5. The following benchmarks are considered here: - Fast reactors: Pu Burner MOX fuel, Pu Burner metal fuel; - PWRs: MOX recycling (bad quality Pu), Multiple MOX recycling

  11. Pu Denaturing by Transmutation of MA in FBR Multi-cycle

    Energy Technology Data Exchange (ETDEWEB)

    Meiliza, Yoshitalia; Saito, Masaki; Sagara, Hiroshi [Tokyo Institute of Technology, 2-12-1-N1-1 Ookayama, Meguro-ku, Tokyo, 1528550 (Japan)

    2009-06-15

    Pu accumulation and its recycling is important in the term of energy resources, however one of the most sensitive issues is non-proliferation in the future fuel cycle based on fast breeder reactor (FBR). The present paper utilizes Protected Pu Production (P{sup 3}) concept for the production of {sup 238}Pu and {sup 242}Pu by Minor Actinides (MA) transmutation to enhance the proliferation resistance of Pu in the fuel. Increase in the {sup 238}Pu and {sup 242}Pu isotopic fraction creates a high rate of internal heat generation by alpha decay (DH) and/or a high neutron source of spontaneous fission (SFN) in Pu that would be encountered during manufacturing and maintaining of nuclear explosive device. The feasibility of denaturing of Pu by MA transmutation in medium size FBR has been studied from the viewpoint of even-mass number Pu accumulation during multi-cycle of Pu and MA. The proliferation resistance property of Pu is also evaluated based on the specific decay heat and spontaneous fission neutron, compared with the reference criteria. In present paper, the P{sup 3} technology based on multi-recycled Pu and MA is compared with the conventional technology based on multi-recycled Pu only. The detail of mass balance behavior is, however, beyond the scope of the present paper. (authors)

  12. Pu and 137Cs in the Yangtze River estuary sediments: distribution and source identification.

    Science.gov (United States)

    Liu, Zhiyong; Zheng, Jian; Pan, Shaoming; Dong, Wei; Yamada, Masatoshi; Aono, Tatsuo; Guo, Qiuju

    2011-03-01

    Pu isotopes and (137)Cs were analyzed using sector field ICP-MS and γ spectrometry, respectively, in surface sediment and core sediment samples from the Yangtze River estuary. (239+240)Pu activity and (240)Pu/(239)Pu atom ratios (>0.18) shows a generally increasing trend from land to sea and from north to south in the estuary. This spatial distribution pattern indicates that the Pacific Proving Grounds (PPG) source Pu transported by ocean currents was intensively scavenged into the suspended sediment under favorable conditions, and mixed with riverine sediment as the water circulated in the estuary. This process is the main control for the distribution of Pu in the estuary. Moreover, Pu is also an important indicator for monitoring the changes of environmental radioactivity in the estuary as the river basin is currently the site of extensive human activities and the sea level is rising because of global climate changes. For core sediment samples the maximum peak of (239+240)Pu activity was observed at a depth of 172 cm. The sedimentation rate was estimated on the basis of the Pu maximum deposition peak in 1963-1964 to be 4.1 cm/a. The contributions of the PPG close-in fallout Pu (44%) and the riverine Pu (45%) in Yangtze River estuary sediments are equally important for the total Pu deposition in the estuary, which challenges the current hypothesis that the riverine Pu input was the major source of Pu budget in this area.

  13. Reaction of alkali nitrates with PuO2

    International Nuclear Information System (INIS)

    Yamashita, T.; Ohuchi, K.; Takahashi, K.; Fujino, T.

    1990-01-01

    Improvement of solubility of plutonium dioxide (PuO 2 ) in acid solution is important to establish the nuclear fuel reprocessing technique for uranium-plutonium mixed oxide fuels. If insoluble PuO 2 can be converted into any soluble plutonium compounds, problems arising from the fuel dissolution process will be reduced to a great extent. Alkali metal plutonates and alkaline-earth plutonates are known to have enhanced solubility in mineral acids. However, the reaction conditions to form such plutonates and characterization thereof are not well elucidated. Then the reactivity and reaction conditions to form lithium and sodium plutonates from their nitrates and PuO 2 were studied at temperatures between 500 and 900 degree C and alkali metal to plutonium atom ratios between 0.5 and 6 by means of thermogravimetry as well as X-ray diffraction technique. The reaction behavior of alkali plutonates will be discussed in comparison with corresponding alkali uranates

  14. Determination of plutonium isotopes (238Pu, 239Pu, 240Pu, 241Pu) in environmental samples using radiochemical separation combined with radiometric and mass spectrometric measurements

    DEFF Research Database (Denmark)

    Xu, Yihong; Qiao, Jixin; Hou, Xiaolin

    2014-01-01

    counting and alpha spectrometry) and inductively coupled plasma mass spectrometry (ICP-MS) were applied for the measurement of plutonium isotopes. The decontamination factors for uranium were significantly improved up to 7.5×105 for 20 g soil compared to the level reported in the literature......, this is critical for the measurement of plutonium isotopes using mass spectrometric technique. Although the chemical yield of Pu in the entire procedure is about 55%, the analytical results of IAEA soil 6 and IAEA-367 in this work are in a good agreement with the values reported in the literature or reference......Pu. However, it is impossible to measure 238Pu using ICP-MS in environmental samples even a decontamination factor as high as 106 for uranium was obtained by chemical separation....

  15. First principles study of α and δ-Pu

    International Nuclear Information System (INIS)

    Chattaraj, Debabrata; Dash, Smruti

    2017-01-01

    The structural and electronic properties of α-and δ-Pu has been investigated using state of the art first principles method. All the calculations have been performed using a plane wave based pseudopotential method under the framework of spin polarized density functional theory. The effect of relativistic spin-orbit interactions on these properties has been investigated. The calculated lattice parameters are found to be within ±1% of the experimental data. The cohesive energy of α-and δ-Pu are calculated to be -3.125 and -3.126 eV/atom. The nature of chemical bonding present in those phases of Pu is depicted by calculated density of states spectra. (author)

  16. Critical mass variation of 239Pu with water dilution

    International Nuclear Information System (INIS)

    Pearlstein, S.

    1996-01-01

    The critical mass of an unreflected solid sphere of 239 Pu is ∼ 10 kg. The increase in critical mass observed for small water dilutions of unreflected 239 Pu spheres is paradoxical. Introducing small amounts of water uniformly throughout the sphere increases the spherical volume containing the same amount of 239 Pu as the critical solid sphere. The increase in radius decreases the surface-to-volume ratio of the sphere, which has the effect to first order of decreasing the neutron leakage, which is proportional to the surface, relative to the fissions, which are proportional to the volume. The reduction in neutron leakage is expected to reduce the critical mass, but instead, the critical mass is observed to increase. It is discussed how changes in the fast neutron spectrum with corresponding changes in the nuclear parameters result in an increase in critical mass for small water dilutions

  17. PU Vulpeculae at the time of spectral change in 1987

    Science.gov (United States)

    Gochermann, J.

    1991-10-01

    A flux-calibrated, low-resolution spectrum of the symbiotic variable PU Vul was obtained when it was changing from an absorption to an emission spectrum in August 1987. The spectral type of the hot component was derived from the Balmer discontinuity, the temperature derived by a Planck curve and by synthetic photometry deduced from the spectrum. A B6 Ia-Iab shell star with a temperature of 13,500 +/-300 K and reddened by interstellar extinction E(B-V) = 0.50 m was found, which harmonizes well with the expectations of Kenyon (1986) about the evolution of PU Vul. An upper limit for the distance of PU Vul was estimated as r = 5.6 +1.5/-1.1 kpc.

  18. Study of U - Pu - Fe alloys (Masurca critical experiment); Etudes d'alliages U-Pu-Fe (experience critique MASURCA)

    Energy Technology Data Exchange (ETDEWEB)

    Barthelemy, P; Boucher, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1965-07-01

    Three compositions have been studied: 73.5 U - 25 Pu - 1.5 Fe (weight %) 74 U - 25 Pu - 1 Fe 74.5 U - 25 Pu - 0.5 Fe Elaboration and Casting are easy. After two weeks in air 74.5 U - 25 Pu - 0.5 Fe alloys are reduced in powder. As-cast alloys containing 1 and 1,5% Fe are kept undamaged during several months. A rapid oxidisation of the alloys is however observed when the samples undergo the phase transformation (at 595 deg. C and 590 deg. C respectively). Ignition tests in the presence of air show that the oxidisation starts at about 250 deg. C and that the reaction does not spread. Ignition is not observed during heating from 20 to 660 deg. C. The transformation temperature, the melting temperature and the thermal expansion coefficients have been determined by dilatometry. Below the transformation temperature, the principal phases are U-Pu zeta and (U, Pu){sub 6}Fe. Thermal conductibility, Young modulus, density and heat of fusion have been measured. Compatibility tests show that between U-Pu-Fe and stainless steel a phase of (U, Pu){sub 6}Fe type is formed. The 74 U - 25 Pu - 1% Fe alloy seems to behave better than 73.5 U - 25 Pu - 1.5% Fe alloy because the (U, Pu){sub 6}Fe layer is two or three times smaller. Finally, the thermal stability has been studied with the 74 U - 25 Pu - 1% Fe alloy. A dilatometric anomaly (very weak expansion) occurs when the sample is heated above transformation temperature and cooled. But there is no anomaly by thermal cycling from 50 deg. C to 400 deg. C and there is no deterioration of alloys by heat treatments at 100 deg. C, 200 deg. C, 300 deg. C during 5 months under vacuum. (authors) [French] Trois compositions ont ete etudiees: 73,5 U - 25 Pu - 1,5 Fe (% ponderaux) 74 U - 25 Pu - 1 Fe 74,5 U - 25 Pu - 0,5 Fe Les elaborations et mises en forme sont-faciles. Les alliages a 0,5% de fer tombent en poudre apres 15 jours d'exposition a l'air. Les alliages a 1 et 1,5% de fer, bruts de coulee, se conservent plusieurs mois. Cependant

  19. Transuranic concentrations in reef and pelagic fish from the Marshall Islands. [/sup 239/Pu, /sup 240/Pu

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.; Eagle, R.J.; Wong, K.M.; Jokela, T.A.

    1980-09-01

    Concentrations of /sup 239 + 240/Pu are reported in tissues of several species of reef and pelagic fish caught at 14 different atolls in the northern Marshall Islands. Several regularities that are species dependent are evident in the distribution of /sup 239 + 240/Pu among different body tissues. Concentrations in liver always exceeded those in bone and concentrations were lowest in the muscle of all fish analyzed. A progressive discrimination against /sup 239 + 240/Pu was observed at successive trophic levels at all atolls except Bikini and Enewetak, where it was difficult to conclude if any real difference exists between the average concentration factor for /sup 239 + 240/Pu among all fish, which include bottom feeding and grazing herbivores, bottom feeding carnivores, and pelagic carnivores from different atoll locations. The average concentration of /sup 239 + 240/Pu in the muscle of surgeonfish from Bikini and Enewetak was not significantly different from the average concentrations determined in these fish at the other, lesser contaminated atolls. Concentrations among all 3rd, 4th, and 5th trophic level species are highest at Bikini where higher environmental concentrations are found. The reasons for the anomalously low concentrations in herbivores from Bikini and Enewetak are not known.

  20. HPLC method for determination of Th, U and Pu in irradiated (Th,Pu)O{sub 2} using mandelic acid as an eluent

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Pranaw; Paul, Sumana; Jaison, Perumpillil George; Telmore, Vijay Madhukar; Alamelu, Devanathan; Aggarwal, Suresh Kumar [Bhabha Atomic Research Centre, Mumbai (India). Fuel Chemistry Div.

    2014-07-01

    Studies for chromatographic separation of Th, U(VI) and Pu(IV) were carried out using mandelic acid as an eluent. The different chromatographic conditions like concentration of mandelic acid, pH of the mobile phase, presence of MeOH and effect of ion interaction reagent (IIR) were studied. The method was optimized for the separation of Th, U(VI) and Pu(IV). At pH<3.5 of mobile phase, Pu(IV) was more retained compared to U(VI) whereas at pH>3.5, reverse trend was observed. The optimized parameters were employed for the separation and determination of Th, U(VI) and Pu(IV) in a dissolved solution of irradiated (Th,Pu)O{sub 2}. Sample treatment was optimized to minimize loss of Pu and Th during chromatographic determination. Studies were carried out using two IIRs to understand the anomalous chromatographic behavior of Pu(IV). Retention behavior of different oxidation states of Pu viz. Pu(III), Pu(IV) and Pu(VI) was also studied in mandelic acid.

  1. Toxicity of inhaled 238PuO2 II

    International Nuclear Information System (INIS)

    Muggenburg, B.A.; Mewhinney, J.A.; Merickel, B.S.; Boecker, B.B.; Hahn, F.F.; Guilmette, R.A.; Mauderly, J.L.; McClellan, R.O.

    1980-01-01

    Studies are in progress to determine dose-response relationships for inhaled 238 PuO 2 . Beagle dogs were given a single, brief, nose-only inhalation exposure to aerosols of monodisperse particles of 238 PuO 2 . Aerosols of two sizes were used, 1.5 μm aerodynamic diameter (AD) and 3.0 μm AD. Dogs were exposed to achieve initial lung burdens of 0.56, 0.28, 0.14, 0.07, 0.03 or 0.01 μCi 238 PuO 2 /kg body weight. Twelve dogs were exposed at each activity level to each aerosol particle size. The local dose around each 3.0 μm AD particle was 10 times higher than the local dose around 1.5 μm AD particles, but the dose averaged over the whole lung was the same at each activity level for both particle sizes. The lung retention of 238 Pu was divided into two phases of clearance. During the first 100 days after exposure, the average retention half-time for 238 Pu in the lung was 310 days. When the solubility changed due to particle breakup, the retention half-time decreased to 180 days during the period from 1OO to 1,500 days after exposure. The first biological effects observed were lymphopenia and neutropenia in peripheral blood. To date, 28 Beagle dogs have died at times from 536 to 1683 days after exposure. Initial lung burdens for the dead dogs ranged from 0.18 to 2.2 μCi 238 Pu/kg body weight. Nine died with radiation pneumonitis and pulmonary fibrosis, 10 died with lung tumors and 19 dogs died with bone tumors. There are 116 exposed and 22 control dogs surviving and under observation. Current patterns of dose versus response are discussed. (author)

  2. Electronic structure of Pu-Ce(-Ga) and Pu-Am(-Ga) alloys, stabilized in the {delta} phase; Structure electronique d'alliages Pu-Ce(-Ga) et Pu-Am(-Ga) stabilises en phase {delta}

    Energy Technology Data Exchange (ETDEWEB)

    Dormeval, M

    2001-09-01

    The behaviour of {delta}-plutonium, stable between 319 and 451 deg C, exhibits numerous singularities which are still a mystery for both physicists and metallurgists. This is due to its complex electronic structure, and in particular to the 5f electrons, which are at the edge between localization and delocalization. The stability domain of the {delta} phase can be extended down to room temperature by alloying with so called 'deltagen atoms' such as gallium (Ga), aluminum (A1), cerium (Ce) or americium (Am). The present work deals, one the one hand, with the influence of cerium and americium solutes regarding the localization of the 5f electrons of {delta}-plutonium, in binary Pu-Ce and Pu-Am alloys. On the other hand, the effect of two different deltagen solutes, simultaneously present, on the stability of the {delta} phase has been studied in ternary Pu-Am-Ga and Pu-Ce-Ga alloys. The electronic structure being strongly related to the crystalline organization, characterization methods such as X-Ray diffraction and EXAFS measurements were used together with electrical resistivity and magnetic susceptibility experiments. These showed that the roles of cerium and americium, supposed to be similar at the beginning of this investigation, are actually very different. Moreover, the additive effect of cerium and gallium, and, americium and gallium, has been demonstrated. Studying plutonium alloys, which are radioactive, also means following their evolution in time. The characteristics of the alloys have then been followed which allowed to detect, in Pu-Ce(-Ga) alloys, a destabilization of the {delta} phase and, to observe, in Pu-Am(-Ga) alloys, the influence of self-irradiation defects on the magnetic response. (author)

  3. Electronic structure of Pu-Ce(-Ga) and Pu-Am(-Ga) alloys, stabilized in the {delta} phase; Structure electronique d'alliages Pu-Ce(-Ga) et Pu-Am(-Ga) stabilises en phase {delta}

    Energy Technology Data Exchange (ETDEWEB)

    Dormeval, M

    2001-09-01

    The behaviour of {delta}-plutonium, stable between 319 and 451 deg C, exhibits numerous singularities which are still a mystery for both physicists and metallurgists. This is due to its complex electronic structure, and in particular to the 5f electrons, which are at the edge between localization and delocalization. The stability domain of the {delta} phase can be extended down to room temperature by alloying with so called 'deltagen atoms' such as gallium (Ga), aluminum (A1), cerium (Ce) or americium (Am). The present work deals, one the one hand, with the influence of cerium and americium solutes regarding the localization of the 5f electrons of {delta}-plutonium, in binary Pu-Ce and Pu-Am alloys. On the other hand, the effect of two different deltagen solutes, simultaneously present, on the stability of the {delta} phase has been studied in ternary Pu-Am-Ga and Pu-Ce-Ga alloys. The electronic structure being strongly related to the crystalline organization, characterization methods such as X-Ray diffraction and EXAFS measurements were used together with electrical resistivity and magnetic susceptibility experiments. These showed that the roles of cerium and americium, supposed to be similar at the beginning of this investigation, are actually very different. Moreover, the additive effect of cerium and gallium, and, americium and gallium, has been demonstrated. Studying plutonium alloys, which are radioactive, also means following their evolution in time. The characteristics of the alloys have then been followed which allowed to detect, in Pu-Ce(-Ga) alloys, a destabilization of the {delta} phase and, to observe, in Pu-Am(-Ga) alloys, the influence of self-irradiation defects on the magnetic response. (author)

  4. Distribution of 238Pu in tissues of fish from the canal in Miamisburg, Oho

    International Nuclear Information System (INIS)

    Kennedy, C.W.; Bartelt, G.E.

    1978-01-01

    The 238 Pu concentrations of varous tissues were measured for seven species of freshwater fish from an ecosystem containing elevated levels of 238 Pu. The highest levels of 238 Pu were found in the gastrointestinal tracts and gills, while the lowest levels were found in muscle tissue. A rapid uptake of 238 Pu was observed for hatchery bluegills introduced into this system. High plutonium concentrations in the gastrointestinal tracts and gills suggest that these organs are potential uptake sites. The presence of 238 Pu in certain tissues (liver, gonads, bone, and muscle) indicates that there is a translocation of 238 Pu from the uptake sites

  5. pH-dependent Pu interaction of one bacterial isolate from Mont Terri Opalinus Clay

    Energy Technology Data Exchange (ETDEWEB)

    Moll, Henry; Cherkouk, Andrea [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Div. Biogeochemistry

    2016-07-01

    Sporomusa sp. MT-2.99 cells displayed a strong pH dependent affinity for Pu. Relatively high maximal Pu loadings as for instance 230 mgPu/g{sub dry} {sub biomass} for Sporomusa sp. at pH 6.1 were achieved. A much slower abiotic reduction of Pu(VI) was observed at pH 4 compared to pH 6.1. Independent on pH an enrichment of Pu(V) in the supernatant and of Pu(IV)- polymers on the biomass was discovered.

  6. Selection of bone samples for 239Pu analyses in man

    International Nuclear Information System (INIS)

    Jee, W.S.S.; Wronski, T.J.; Smith, J.M.; Kimmel, D.B.; Miller, S.C.; Stover, B.J.

    1981-01-01

    Studies on the skeletal macrodistribution, microdistribution, and toxicity of 239 Pu and studies on bone turnover rates show that trabecular bone sites with high turnover rates have the greatest affinity for 239 Pu. In the adult beagle, these high-turnover, trabecular bone sites also show a higher occurrence of osteosarcomas. Correspondingly, high-turnover bone sites in the human would include the ilium (pelvis) and lumbar vertebrae (LVB), sites that are readily obtainable at autopsy. We recommend that the trabecular bone of the ilium and of the LVB be sampled to determine the skeletal radionuclide content of humans

  7. Estimation of 239Pu in urine, influence of Sulkowich reagent

    International Nuclear Information System (INIS)

    Kalaiselvan, S.; Prasad, M.V.R.; Jeevanram, R.K.

    1988-01-01

    Plutonium is known to be co-precipitated with Sulkowich reagent as calcium ammonium oxalate. In adopting this technique for bio-assay of plutonium, its accuracy depends on the self-absorption of the resulting precipitate in each urine sample. Pu recovery experiments were carried out with varying concentration of Ca and Mg, using different volumes of Sulkowich reagent. When the sample volume is 500 ml, Pu in urine can be estimated with an accuracy and precision of 74.38%+-7.4%, with a detection limit of 0.06 Bq (1.6 pCi) per dm 3 . (author) 3 refs.; 2 figs.; 2 tabs

  8. Pu241 cross-sections below 1 keV

    International Nuclear Information System (INIS)

    Doherty, G.

    1966-12-01

    Early in 1965 a new data file (DFN 40) for Pu241 covering the energy range 10 - 4 eV to 15 MeV was prepared for the UKAEA Nuclear Data Library. The data above 1 keV are described by Douglas (AWRE 0-101/64) and the data below 1 keV are set out in this report. During the past year a number of additional measurements have been reported for Pu241 and a brief summary of these measurements and their implications for the data on the file are given. (author)

  9. Determination of Plutonium Activity Concentrations and 240Pu/239Pu Atom Ratios in Brown Algae (Fucus distichus) Collected from Amchitka Island, Alaska

    International Nuclear Information System (INIS)

    Hamilton, T F; Brown, T A; Marchetti, A A; Martinelli, R E; Kehl, S R

    2005-01-01

    Plutonium-239 ( 239 Pu) and plutonium-240 ( 240 Pu) activity concentrations and 240 Pu/ 239 Pu atom ratios are reported for Brown Algae (Fucus distichus) collected from the littoral zone of Amchitka Island (Alaska) and at a control site on the Alaskan peninsula. Plutonium isotope measurements were performed in replicate using Accelerator Mass Spectrometry (AMS). The average 240 Pu/ 239 Pu atom ratio observed in dried Fucus d. collected from Amchitka Island was 0.227 ± 0.007 (n=5) and compares with the expected 240 Pu/ 239 Pu atom ratio in integrated worldwide fallout deposition in the Northern Hemisphere of 0.1805 ± 0.0057 (Cooper et al., 2000). In general, the characteristically high 240 Pu/ 239 Pu content of Fucus d. analyzed in this study appear to indicate the presence of a discernible basin-wide secondary source of plutonium entering the marine environment. Of interest to the study of plutonium source terms within the Pacific basin are reports of elevated 240 Pu/ 239 Pu atom ratios in fallout debris from high-yield atmospheric nuclear tests conducted in the Marshall Islands during the 1950s (Diamond et al., 1960), the wide range of 240 Pu/ 239 Pu atom ratio values (0.19 to 0.34) observed in sea water, sediments, coral and other environmental media from the North Pacific Ocean (Hirose et al., 1992; Buesseler, 1997) and updated estimates of the relative contributions of close-in and intermediate fallout deposition on oceanic inventories of radionuclidies, especially in the Northern Pacific Ocean (Hamilton, 2004)

  10. Measurement of the fission cross-section of $^{240}$Pu and $^{242}$Pu at CERN's n_TOF Facility

    CERN Multimedia

    Pavlik, A F; Gonzalez romero, E M

    The n_TOF Collaboration proposes to continue the fission program, already started in 2002-2004, taking advantage of the newly constructed Work Sector Type A, with the measurement of the two isotopes : $^{240}$ Pu and $^{242}$ Pu. They are both of major importance for reactor physics applications and are included in the Nuclear Energy Agency (NEA) High Priority List [1], in the NEA WPEC Subgroup 26 Report on the accuracy of nuclear data for advanced reactor designe [2] and in the EU 6$^{th}$ Framework Programme IP-EUROTRANS/NUDATRA reports [3]. Based on those requests, the measurement of the fission cross-section of the two Pu isotopes is one of the objectives of the project ANDES of the FP7 EURATOM program [4].

  11. Nitridation of U and Pu recovered in liquid Cd cathode by molten salt electrorefining of (U,Pu)N

    Energy Technology Data Exchange (ETDEWEB)

    Satoh, Takumi; Iwai, Takashi; Arai, Yasuo [Japan Atomic Energy Agency (Japan)

    2009-06-15

    Solid solutions of actinide mono-nitrides have been proposed as a candidate fuel of the accelerator-driven system (ADS) and Gen.IV-type fast reactors because the thermal conductivity and metal density are higher than those of actinide oxides and also they have high melting temperature. Pyrochemical process has several advantages over conventional wet process in treating of spent nitride fuel. One of the key technologies of the pyrochemical reprocessing of nitride fuel is the formation of the nitrides from actinides in the liquid Cd cathode. The nitridation-distillation combined method was developed and has been adopted to convert the actinides to the nitrides. In this method, the nitridation of actinides and the distillation of Cd occurred simultaneously by heating the actinide-Cd alloys in N{sub 2} gas stream. In the present study, the nitride formation behavior of U and Pu recovered in Cd cathode by molten salt electrorefining of (U,Pu)N was experimentally investigated. In addition, the nitride pellet was prepared form the powder obtained by the nitridation of U and Pu recovered in Cd cathode. (U,Pu)N (PuN = 80 mol %) was used as the starting material in the experiment. Molten salt electrorefining of (U,Pu)N pellet was carried out in the LiCl-KCl eutectic salt with 1.2 wt% PuCl{sub 3} and 0.3 wt% UCl{sub 3} of about 110 g at the constant anodic potential of -0.60 to -0.55 V vs. Ag/AgCl for about 9 hours at 773 K. After the electrorefining, about 42 % of U and Pu in the starting (U,Pu)N pellet was dissolved at the anode and recovered into the liquid Cd cathode. The recovered U-Pu-Cd alloy was heated in an alumina crucible at 973 K for 10 hours under N{sub 2} gas (99.999 %) stream (0.015 L/min). Fine black powder was recovered after heating the U-Pu-Cd alloy. The powder was identified as the single phase solid solution of (U,Pu)N by the XRD analysis. After milling in the agate mortar for 1 hour, the powder was compacted into green pellet under a pressure of about

  12. Redox thermodynamic data of plutonium in acidic and carbonate media. Pu(V) stability

    International Nuclear Information System (INIS)

    Capdevila, H.

    1992-01-01

    Pu redox equilibria are studied in acidic and carbonate media in this thesis, to build a thermodynamic data bank consistent with the TDB (NEA-OECD) one and in connection with radioactive waste disposal programs. Literature is discussed and reinterpreted. The experimental method is tested with Uranium preliminary measurements. The reversible redox potentials (PuO 2 + and Pu 4+ /Pu 3+ ) are measured using the cyclic voltametric technique in perchloric media at several ionic strengths (from 0.5 to 3M) and temperatures (from 0 to 70 deg C). The Specific Interaction Theory (SIT) is used to measured activity coefficients and to extrapolate data to the standard conditions. The potentials variations versus temperature are linear in first approximation: the entropy changes are found constant from 0 to 70 deg C and the heat capacity changes are within uncertainties. The standard constant of PuO 2 + disproportionation into PuO 2 2+ and Pu 3+ is deduced from spectrophotometric measurements performed in perchloric media around pH=1 where Pu 4+ hydrolysis is discussed. The Pu non-reversible standard potentials (PuO 2 2+ /Pu 4+ for instance) are then calculated and validated with a spectrophotometric study of Pu 4+ formation from PuO 2 2+ and Pu 3+ in a 1M perchloric acidic solution. The Pu(VI/V) redox potential, activity coefficients and entropies are measured using the same technique in concentrated carbonate media. The limiting complex standard formation constants and the redox potential shifts (between acidic and carbonate media) are then discussed among the U, Np, Pu and Am actinides. A spectrophotometric study of the equilibrium between the complexes with 5 and 4 carbonate ligands allowed to measure Pu(IV) limiting complex stability at several ionic strengths. (author). 26 tabs., 46 figs., 95 refs

  13. Surrogate 239Pu(n, fxn) and 241Pu(n, fxn) average fission-neutron-multiplicity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Burke, J. T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Alan, B. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Akindele, O. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Casperson, R. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hughes, R. O. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Fisher, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-26

    We have constructed a new neutron-charged-particle detector array called NeutronSTARS. It has been described extensively in LLNL-TR-703909 [1] and Akindele et al [2]. We have used this new neutron-charged-particle array to measure the 241Pu and 239Pu fissionneutron multiplicity as a function of equivalent incident-neutron energy from 100 keV to 20 MeV. The experimental approach, detector array, data analysis, and results are summarized in the following sections.

  14. Measurements of the neutron-induced fission cross sections of 240Pu and 242Pu relative to 235U

    International Nuclear Information System (INIS)

    Behrens, J.W.; Browne, J.C.; Carlson, G.W.

    1976-01-01

    A continuation is given of the fission-cross-section ratio measurements in progress at the Lawrence Livermore Laboratory. Preliminary results are provided for the 240 Pu/ 235 U and 242 Pu/ 235 U ratios from 0.02 to 30 MeV and 0.1 to 30 MeV, respectively. Using the threshold-cross-section method, the ratios were normalized to the values 1.368 +- 0.030 and 1.116 +- 0.025, respectively, from 1.75 to 4.00 MeV

  15. Monte Carlo simulations of the stability of delta-Pu

    DEFF Research Database (Denmark)

    Landa, A.; Soderlind, P.; Ruban, Andrei

    2003-01-01

    The transition temperature (T-c) for delta-Pu has been calculated for the first time. A Monte Carlo method is employed for this purpose and the effective cluster interactions are obtained from first-principles calculations incorporated with the Connolly-Williams and generalized perturbation methods...

  16. Fractionation of (137)Cs and Pu in natural peatland.

    Science.gov (United States)

    Mihalík, Ján; Bartusková, Miluše; Hölgye, Zoltán; Ježková, Tereza; Henych, Ondřej

    2014-08-01

    High Cs-137 concentrations in plants growing on peatland inspired us to investigate the quantity of its bioavailable fraction in natural peat. Our investigation aims to: a) estimate the quantity of bioavailable Cs-137 and Pu present in peat, b) verify the similarity of Cs-137 and K-40 behaviours, and c) perform a quantification of Cs-137 and Pu transfer from peat to plants. We analysed the vertical distribution of Cs-137 and Pu isotopes in the peat and their concentrations in plants growing on these places. Bioavailability of radionuclides was investigated by sequential extraction. Sequential analyses revealed that it was the upper layer which contained the majority of Cs-137 in an available form while deeper layers retained Cs-137 in immobile fractions. We can conclude that 18% of all Cs-137 in the peat is still bioavailable. Despite of the low quantity of bioavailable fraction of Cs-137 its transfer factor reached extremely high values. In the case of Pu, 64% of its total amount was associated with fulvic/humic acids which resulted in the high transfer factor from peat to plants. 27 years after the Chernobyl nuclear accident, the significant part of radionuclides deposited in peatland is still bioavailable. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. 239,240Pu distribution in the Japanese

    International Nuclear Information System (INIS)

    Hisamatsu, Shun-ichi

    1996-01-01

    Distribution of 239,240 Pu and 241 Am in the Japanese were reviewed, and compared with those estimated with ICRP metabolic models. Inhalation and ingestion amount of these nuclides were calculated from simple models, and used as input to the ICRP metabolic models. ICRP-30 model or the combination of ICRP-66 lung model and ICRP-67 metabolic model were used for the calculation. The estimated 239,240 Pu concentrations in lung, liver, skeleton, kidney and muscle by using of the combination of ICRP-66 and 67 models agreed well with the measured data in most cases. The contribution of ingestion intake to body burden of 239,240 Pu was estimated to be 12% with 5 x 10 -4 as f 1 value. The combination of ICRP-66 and 67 model could described fairly well the organ burden of 241 Am measured in Akita and Niigata district. The 241 Am grown from 241 Pu in the human body was calculated to contribute 90% of the burden. (author)

  18. Analysis of safety margins for PuO2 containers

    International Nuclear Information System (INIS)

    Hubert, P.; Tomachevsky, E.

    1987-11-01

    In the regular manner the containers for PuO 2 transport are type B(U) and give satisfaction to the AIEA proofs. However the vigour of this conception's containers and the analysis of other radioactive containers permit to think that large safety margins exist. In this paper, the importance and the kind of these margins are studied [fr

  19. Wood fibre density measurement with 238 Pu radiation

    International Nuclear Information System (INIS)

    Barry, B.J.; Baker, D.B.

    1996-01-01

    The form of the curve of attenuation by wood fibre of the X radiation from 238 Pu has been determined. An exponential function containing a term second order in the areal density of the fibre described the curve accurately. The effect of scatter is negligible, even with an uncollimated radiation beam. (author). 18 refs., 1 tab., 6 figs

  20. Evaluation of the neutron cross sections for Pu-240

    International Nuclear Information System (INIS)

    Weston, L.W.; Arthur, E.D.

    1987-04-01

    The present evaluation is proposed to supersede the ENDF/B-V, Revision 2 file for 240 Pu. In this work, resonance parameters, cross sections, energy distributions, and angular distributions have been modified. These changes are outlined in detail and appropriate references included. 37 refs., 21 figs., 2 tabs

  1. Mechanical properties of 238PuO2

    International Nuclear Information System (INIS)

    Petrovic, J.J.; Hecker, S.S.; Land, C.C.; Rohr, D.L.

    1977-04-01

    The mechanical properties of 238 PuO 2 have been examined in the Los Alamos Scientific Laboratory mechanical test facility built to handle α-radioactive materials. Compression tests were conducted as a function of temperature, strain rate, grain size, density, and storage time. At temperatures less than or equal to 1400 0 C, test specimens of 238 PuO 2 exhibit pseudobrittle behavior due to internal cracks. Plastic deformation is ''localized'' at the crack tips. Generalized plastic deformation is observed at 1500 0 C. Ultimate stress values decrease markedly with increasing temperature and decreasing strain rate, and decrease less with decreasing density, increasing storage time, and increasing grain size. Room temperature fracture is transgranular, whereas intergranular fracture predominates at elevated temperatures. Crack-free specimens of 239 PuO 2 exhibit extensive plastic deformation at 1000 0 C and above. The relationship of these test results to the impact properties of 238 PuO 2 fuel in radioisotope thermoelectric generators is discussed

  2. PuMA: the Porous Microstructure Analysis software

    Science.gov (United States)

    Ferguson, Joseph C.; Panerai, Francesco; Borner, Arnaud; Mansour, Nagi N.

    2018-01-01

    The Porous Microstructure Analysis (PuMA) software has been developed in order to compute effective material properties and perform material response simulations on digitized microstructures of porous media. PuMA is able to import digital three-dimensional images obtained from X-ray microtomography or to generate artificial microstructures. PuMA also provides a module for interactive 3D visualizations. Version 2.1 includes modules to compute porosity, volume fractions, and surface area. Two finite difference Laplace solvers have been implemented to compute the continuum tortuosity factor, effective thermal conductivity, and effective electrical conductivity. A random method has been developed to compute tortuosity factors from the continuum to rarefied regimes. Representative elementary volume analysis can be performed on each property. The software also includes a time-dependent, particle-based model for the oxidation of fibrous materials. PuMA was developed for Linux operating systems and is available as a NASA software under a US & Foreign release.

  3. PDF analysis of PuAl alloys local structure

    Energy Technology Data Exchange (ETDEWEB)

    Platteau, C. [CEA Valduc, 21120 Is-sur-Tille (France)], E-mail: platteau.cyril@yahoo.fr; Bruckel, P.; Ravat, B.; Delaunay, F. [CEA Valduc, 21120 Is-sur-Tille (France)

    2009-03-15

    For understanding singular properties of plutonium, there is a need in studying the average and local atomic structure in Pu alloys. To study the local structure of the {delta} phase, a pair distribution function (PDF) analysis was done and has shown some significant differences with the average structure.

  4. Second Generation Dutch Pulsar Machine - PuMa-II

    NARCIS (Netherlands)

    Karuppusamy, Ramesh; Stappers, Ben; Slump, Cornelis H.; van der Klis, Michiel

    2004-01-01

    The Second Generation Pulsar Machine (PuMa- II) is under development for the Westerbork Synthesis Radio Telescope. This is a summary of th e system design and architecture. We show that state of the art pulsar research is possible with commercially available hardware components. This approach

  5. Stabilizing And Packaging Pu Materials Per 3013 At SRS

    International Nuclear Information System (INIS)

    STEVE, HENSEL

    2005-01-01

    The Savannah River Site (SRS) began packaging Pu metals into 3013 containers in April, 2003 and oxides in October, 2003. A total of 919 outer 3013 containers were made in the FB-Line at SRS when stabilization and packaging was completed in January, 2005. Experiences, lessons learned, and an overview of packaging activities are presented

  6. Biogeochemical Cycling and Environmental Stability of Pu Relevant to Long-Term Stewardship of DOE Sites

    Energy Technology Data Exchange (ETDEWEB)

    Honeyman, Bruce D.

    2006-06-01

    The overall objective of this proposed research is to understand the biogeochemical cycling of Pu in environments of interest to long-term DOE stewardship issues. Central to Pu cycling (transport initiation to immobilization) is the role of microorganisms. The hypothesis underlying this proposal is that microbial activity is the causative agent in initiating the mobilization of Pu in near-surface environments: through the transformation of Pu associated with solid phases, production of extracellular polymeric substances (EPS) carrier phases, and the creation of microenvironments. Also, microbial processes are central to the immobilization of Pu species, through the metabolism of organically complexed Pu species and Pu associated with extracellular carrier phases and the creation of environments favorable for Pu transport retardation.

  7. Biogeochemical Cycling and Environmental Stability of Pu Relevant to Long-Term Stewardship of DOE Sites

    Energy Technology Data Exchange (ETDEWEB)

    Francis, Arokiasamy J.; Santschi, Peter H.; Honeyman, Bruce D.

    2005-06-01

    The overall objective of this proposed research is to understand the biogeochemical cycling of Pu in environments of interest to long-term DOE stewardship issues. Central to Pu cycling (transport initiation to immobilization) is the role of microorganisms. The hypothesis underlying this proposal is that microbial activity is the causative agent in initiating the mobilization of Pu in near-surface environments: through the transformation of Pu associated with solid phases, production of extracellular polymeric substances (EPS) carrier phases, and the creation of microenvironments. Also, microbial processes are central to the immobilization of Pu species, through the metabolism of organically complexed Pu species and Pu associated with extracellular carrier phases and the creation of environments favorable for Pu transport retardation.

  8. Microautoradiography in studies of Pu(V) sorption by trace and fracture minerals in tuff

    International Nuclear Information System (INIS)

    Vaniman, D.; Furlano, A.; Chipera, S.; Thompson, J.; Triay, I.

    1996-01-01

    Microautoradiography was used to evaluate the mineralogic basis of Pu(V) retention by tuffs from Yucca Mountain, Nevada. Altered orthopyroxenes and oxide minerals are associated with high Pu retention but are limited to specific stratigraphic horizons. A weaker but more general association of Pu with smectite occurs in most samples. Thin-sections that cross fractures allow comparative studies of Pu retention by fracture-lining versus matrix minerals. Using Ag metal in emulsions as a measure of underlying Pu concentration, electron-microprobe analysis can quantify Pu retention along fracture walls and provide mineral/mineral Pu retention factors. For smectite-lined microfractures in zeolitized tuff, the smectite/clinoptilolite Pu retention factor is >80

  9. Late effects of 239Pu administered at representative stages of gestation

    International Nuclear Information System (INIS)

    Andrew, F.D.; Sikov, M.R.

    1979-01-01

    Evaluation of effects on postnatal growth and survival times up to about 21 months following 239 Pu administration support our working hypothesis that prenatal 239 Pu exposures may adversely affect the growth and survival of the offspring

  10. 239Pu(n, 2n) and 241Pu(n, 2n) surrogate cross section measurements using NeutronSTARS

    Energy Technology Data Exchange (ETDEWEB)

    Burke, J. T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Alan, B. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Akindele, O. A. [Univ. of California, Berkeley, CA (United States); Casperson, R. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hughes, R. O. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Koglin, J. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Tamashiro, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Oregon State Univ., Corvallis, OR (United States); Kolos, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Norman, E. B. [Univ. of California, Berkeley, CA (United States); Saastamoinen, A. [Univ. of California, Los Angeles, CA (United States); Padilla, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Univ. of California, Los Angeles, CA (United States); Fisher, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-12-08

    The goal of this project was to develop a new approach to measuring (n,2n) reactions for isotopes of interest. We set out to measure the 239Pu(n,2n) and 241Pu(n,2n) cross sections by directly detecting the 2n neutrons that are emitted. With the goal of improving the 239Pu(n,2n) cross section and to measure the 241Pu(n,2n) cross section for the first time. To that end, we have constructed a new neutron-charged-particle detector array called NeutronSTARS. It has been described extensively in Casperson et al. [1] and in Akindele et al. [2]. We have used this new neutron-charged-particle array to measure the 241Pu and 239Pu fission neutron multiplicity as a function of equivalent incident-neutron energy from 100 keV to 20 MeV. We have made a preliminary determination of the 239Pu(n,2n) and 241Pu(n,2n) cross sections from the surrogate 240Pu(α,α’2n) and 242Pu(α,α’2n) reactions respectively. The experimental approach, detector array, data analysis, and results to date are summarized in the following sections.

  11. Towards a spectroscopic standard database for Pu in repository environments

    International Nuclear Information System (INIS)

    Amme, M.

    2005-01-01

    Full text of publication follows: The alteration behaviour of Pu in geological and technical environments is, although of crucial importance for example in final repository assessment procedures for high-level nuclear waste, not sufficiently investigated. Since Pu chemistry differs significantly from U behaviour (mostly due to the different stabilities of the +IV oxidation states of both elements), conclusions based on the uranium analogy cannot be extended to Pu chemistry in many cases. In order to examine precisely the alteration behaviour of Pu under repository storage conditions, customized tools for the spectroscopic identification of the element need to be developed. We are currently constructing systematically a database of Pu compounds and collect their spectra for this purpose. Pu compounds (with the element in the oxidation states +III, +IV, +V, and +VI) are synthesised, mostly by using hydrothermal synthesis techniques [1]. Compounds of high importance for repository studies are: Carbonates, (oxy)hydroxides, silicates, peroxides, and phosphates. The products are characterised by Scanning Electron Microscopy (SEM), X-Ray Photoelectron spectroscopy (XPS), and X-Ray diffraction (XRD). Furthermore, vibrational spectra (Raman and IR) of the substances will be recorded. These will allow the unambiguous identification of chemically similar compounds, once the database is compiled: Although reported for a few cases with nuclear material only, the combined investigation of solids with Raman [2,3] and SEM-EDX [3] in a combined mode, especially when spatially resolving, holds great potential An investigation with accelerator-based XAS techniques is planned within the framework of the Excellence network Actinet 6. [1] Grigorev, M., Bessonov, A., Makarenkov, V., Fedoseev, A., Model of the (PuO 2 ) 2 SiO 4 * 2H 2 O crystal structure, based on powder X-ray diffraction data, Radiochemistry, Vol. 45, No 3 (2003) 257-260. [2] M. Amme, B. Renker, B. Schmid, M. Feth, H

  12. Temporal record of Pu isotopes in inter-tidal sediments from the northeastern Irish Sea

    Energy Technology Data Exchange (ETDEWEB)

    Lindahl, Patric, E-mail: patriclindahl@yahoo.com [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Worsfold, Paul; Keith-Roach, Miranda [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Andersen, Morten B. [Bristol Isotope Group, School of Earth Sciences, University of Bristol, Wills Memorial Building, Bristol BS8 1RJ (United Kingdom); Kershaw, Peter; Leonard, Kins [The Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory, Pakefield Road, Suffolk NR33 0HT (United Kingdom); Choi, Min-Seok [Division of Earth and Environmental Science, Korea Basic Science Institute, 113 Gwahangno, Yusung-gu, Daejon 305-333 (Korea, Republic of); Boust, Dominique [Laboratoire de Radioecologie, Institut de Radioprotection et de Surete Nucleaire, BP 10, 50130 Cherbourg-Octeville (France); Lesueur, Patrick [University of Caen Basse Normandie, M2C UMR CNRS 6143, 14000 Caen (France)

    2011-11-01

    A depth profile of {sup 239}Pu and {sup 240}Pu specific activities and isotope ratios was determined in an inter-tidal sediment core from the Esk Estuary in the northeastern Irish Sea. The study site has been impacted with plutonium through routine radionuclide discharges from the Sellafield nuclear reprocessing plant in Cumbria, NW England. A pronounced sub-surface maximum of {approx} 10 kBq kg{sup -1} was observed for {sup 239+240}Pu, corresponding to the peak in Pu discharge from Sellafield in 1973, with a decreasing trend with depth down to {approx} 0.04 kBq kg{sup -1} in the deeper layers. The depth profile of {sup 239+240}Pu specific activities together with results from gamma-ray spectrometry for {sup 137}Cs and {sup 241}Am was compared with reported releases from the Sellafield plant in order to estimate a reliable sediment chronology. The upper layers (1992 onwards) showed higher {sup 239+240}Pu specific activities than would be expected from the direct input of annual Sellafield discharges, indicating that the main input of Pu is from the time-integrated contaminated mud patch of the northeastern Irish Sea. The {sup 240}Pu/{sup 239}Pu atom ratios ranged from {approx} 0.03 in the deepest layers to > 0.20 in the sub-surface layers with an activity-weighted average of 0.181. The decreasing {sup 240}Pu/{sup 239}Pu atom ratio with depth reflects the changing nature of operations at the Sellafield plant from weapons-grade Pu production to reprocessing spent nuclear fuel with higher burn-up times in the late 1950s. In addition, recent annual {sup 240}Pu/{sup 239}Pu atom ratios in winkles collected during 2003-2008 from three stations along the Cumbrian coastline showed no significant spatial or temporal differences with an overall average of 0.204, which supports the hypothesis of diluted Pu input from the contaminated mud patch. - Highlights: {yields} Depth profiles of {sup 239}Pu and {sup 240}Pu determined in a northeastern Irish Sea sediment. {yields

  13. Determination of Pu Oxidation states in the HCl Media Using with UV-Visible Absorption Spectroscopic Techniques

    International Nuclear Information System (INIS)

    Lee, Myung Ho; Suh, Mu Yeol; Park, Kyoung Kyun; Park, Yeong Jae; Kim, Won Ho

    2006-01-01

    The spectroscopic characteristics of Pu (III, IV, V, VI) in the HCl media were investigated by measuring Pu oxidation states using a UV-Vis-NIR spectrophotometer (400-1200 nm) after adjusting Pu oxidation states with oxidation/reduction reagents. Pu in stock solution was reduced to Pu(III) with NH 2 OH · HCl, and oxidized to Pu(IV) and Pu(VI) with NaNO 2 and HCIO 4 , respectively. Also, Pu(V) was adjusted in the Pu(VI) solution with NH 2 OH · HCl. The major absorption peaks of Pu (IV) and Pu(III) were measured in the 470 nm and 600 nm, respectively. The major absorption peaks of Pu (VI) and Pu(V) were measured in the 830 nm and 1135 nm, respectively. There was not found to be significant changes of UV-V is absorption spectra for Pu(III), Pu(IV) and Pu(VI) with aging time, except that an unstable Pu(V) immediately reduced to Pu(III).

  14. Spatial and temporal variations of plutonium isotopes (238Pu and 239,240Pu) in sediments off the Rhone River mouth (NW Mediterranean)

    International Nuclear Information System (INIS)

    Lansard, B.; Charmasson, S.; Gasco, C.; Anton, M.P.; Grenz, C.; Arnaud, M.

    2007-01-01

    The dispersion and fate of the Rhone River inputs to the Gulf of Lions (Northwestern Mediterranean Sea) have been studied through the spatial and temporal distributions of plutonium isotopes in continental shelf sediments. Plutonium isotopes ( 238 Pu and 239,240 Pu) are appropriate tracers to follow the dispersion of particulate matter due both to their high affinity for particles and their long half-lives. In the Rhone River valley, plutonium isotopes originate from both the weathering of the catchment basin contaminated by global atmospheric fallout, and the liquid effluents released from the Marcoule reprocessing plant since 1961. This work presents a first detailed study on 238 Pu and 239,240 Pu distributions in sediments from the Rhone prodelta to the adjacent continental shelf, since the decommissioning of Marcoule in 1997. The vertical distribution of Pu isotopes has been analysed in a 4.75 m long core sampled in 2001 at the Rhone mouth. Despite this length, plutonium is found at the last 10 cm, manifesting the high sedimentation rate of the prodeltaic area and its ability for trapping fine-grained sediments and associated contaminants. The highest 238 Pu and 239,240 Pu concentrations reached 1.26 and 5.97 Bq kg -1 respectively and were found within the layer 280-290 cm. The 238 Pu/ 239,240 Pu activity ratios (AR) demonstrated an efficient and huge trapping of the Pu isotopes derived from Marcoule. The fresh sediments, located on the top of the core, show lower plutonium activity concentrations and lower 238 Pu/ 239,240 Pu ratios. This decrease is in close relation with the shut down of the Marcoule reprocessing plant in 1997. In 2001, plutonium isotopes were also analysed in 21 surface sediments located offshore and concentrations ranged from 0.03 to 0.17 Bq kg -1 for 238 Pu and from 0.33 to 1.72 Bq kg -1 for 239,240 Pu. The 238 Pu/ 239,240 Pu AR ranged from 0.24 close to the river mouth to 0.06 southwards, indicating the decreasing influence of the

  15. Disposition of 238Pu(NO3)4 following inhalation by beagle dogs

    International Nuclear Information System (INIS)

    Dagle, G.E.; Cannon, W.C.; Schirmer, R.E.; Stevens, D.L. Jr.

    1979-01-01

    Twelve dogs were given a single inhalation exposure to 238 Pu(NO 3 ) 4 to study deposition and translocation up to 1 yr. Preliminary data suggest a greater and more rapid translocation of 238 Pu(NO 3 ) 4 to bone and liver than was observed for 239 Pu(NO 3 ) 4

  16. Subcellular binding of 239Pu in the liver of selected species of rodents

    International Nuclear Information System (INIS)

    Winter, R.

    1980-01-01

    The subcellular distribution of 239 Pu in the liver of selected rodent species was investigated as well as the relation between 239 Pu and the iron metabolism. The goal of the investigation was to find out why the liver discharge of 239 Pu from the liver varies so much between species. (orig.) [de

  17. 238Pu fuel form processes. Final report, January-September 1983

    International Nuclear Information System (INIS)

    Mosley, W.C.; Taylor, D.H.

    1983-01-01

    Progress is reported on the following: analytical studies of weld-quench cracking in DOP-26 iridium alloy, iridium/ 238 PuO 2 compatibility test, surface area measurements of 238 PuO 2 using the Blaine air permeability apparatus, and helium release from 238 PuO 2

  18. Detection of Pu in Pacific Ocean water with AMS related to the Fukushima accident

    Energy Technology Data Exchange (ETDEWEB)

    Hain, Karin; Faestermann, Thomas; Fimiani, Leticia; Guzman, Jose Manuel; Korschinek, Gunther; Kortmann, Florian; Lierse v Gostomski, Christoph; Ludwig, Peter [TUM (Germany); Golser, Robin; Steier, Peter [Universitaet Wien (Austria); Yamada, Masatoshi [Hirosaki University (Japan)

    2016-07-01

    The concentration of plutonium (Pu) and its isotopic ratios were determined by accelerator mass spectrometry (AMS) in Pacific Ocean water samples. The isotopic ratios {sup 240}Pu/{sup 239}Pu and {sup 241}Pu/{sup 239}Pu can be used to identify a possible release of Pu into the ocean by the Fukushima accident. {sup 241}Pu from fallout of nuclear weapon testings has already significantly decayed. {sup 241}Am, the daughter nuclide of {sup 241}Pu, causes isobaric background on {sup 241}Pu in mass-spectrometric measurements. Therefore, Am and Pu had to be separated chemically using extraction chromatography. The method was verified by analyzing certified reference material. 12 sea water samples, collected at different depths, were prepared at the Radiochemie Muenchen. The concentration of Pu was measured with AMS at the Maier-Leibnitz-Laboratory in Munich and the Vienna Environmental Research Laboratory (VERA). After a short motivation related to the Fukushima accident, the chemical separation method will be presented. Preliminary results of the distribution of Pu in ocean water will be discussed.

  19. Historical changes in 239Pu and 240Pu sources in sedimentary records in the East China Sea: Implications for provenance and transportation

    DEFF Research Database (Denmark)

    Wang, Jinlong; Baskaran, Mark; Hou, Xiaolin

    2017-01-01

    from 0.158 to 0.297 and were mostly higher than the mean global fallout value of 0.18. The 239,240Pu inventories in the ECS varied widely, from 2 to 807 Bqm−2, with the highest values commonly found in the coastal areas. In the Yangtze Estuary, the mean 239+240Pu activity concentration is close...... to the estimated value of the suspended material from the Yangtze River catchment (0.18 Bqkg−1), and the 240Pu/239Pu atom ratio was found to be ∼0.18, which indicates that the Yangtze River input is the dominant source of Pu for this area. The total annual Yangtze River input of 239+240Pu was estimated to be 2...

  20. Mathematical modeling of radiation-chemical processes in HNO3 solutions of Pu. 5. Effect of [HNO3] on rate constants of radiation-chemical and chemical reactions of Pu ions

    International Nuclear Information System (INIS)

    Vladimirova, M.V.

    1993-01-01

    Dependences of rate constants on [HNO 3 ] are obtained for the reactions Pu(IV) + OH, Pu(IV) + NO 3 , Pu(V) + NO 2 , Pu(III) + NO 2 , Pu(V) + Pu(III), Pu(IV) + Pu(IV), and Pu(V) + Pu(V). These dependences are obtained for [HNO 3 ] = 0.3-6 M using existing experimental and literature data and the data obtained using mathematical modeling. The correctness of the resulting dependences is checked by comparing the calculated and experimental kinetic laws for the behavior of Pu in 0.3, 0.4, 0.6, and 1.6 M HNO 3 . 17 refs., 15 figs., 2 tabs

  1. Anaerobic Biotransformation and Mobility of Pu and of Pu-EDTA

    Energy Technology Data Exchange (ETDEWEB)

    Xun, Luying

    2009-11-20

    The enhanced mobility of radionuclides by co-disposed chelating agent, ethylenediaminetetraacetate (EDTA), is likely to occur only under anaerobic conditions. Our extensive effort to enrich and isolate anaerobic EDTA-degrading bacteria has failed. Others has tried and also failed. To explain the lack of anaerobic biodegradation of EDTA, we proposed that EDTA has to be transported into the cells for metabolism. A failure of uptake may contribute to the lack of EDTA degradation under anaerobic conditions. We demonstrated that an aerobic EDTA-degrading bacterium strain BNC1 uses an ABC-type transporter system to uptake EDTA. The system has a periplasmic binding protein that bind EDTA and then interacts with membrane proteins to transport EDTA into the cell at the expense of ATP. The bind protein EppA binds only free EDTA with a Kd of 25 nM. The low Kd value indicates high affinity. However, the Kd value of Ni-EDTA is 2.4 x 10^(-10) nM, indicating much stronger stability. Since Ni and other trace metals are essential for anaerobic respiration, we conclude that the added EDTA sequestrates all trace metals and making anaerobic respiration impossible. Thus, the data explain the lack of anaerobic enrichment cultures for EDTA degradation. Although we did not obtain an EDTA degrading culture under anaerobic conditions, our finding may promote the use of certain metals that forms more stable metal-EDTA complexes than Pu(III)-EDTA to prevent the enhanced mobility. Further, our data explain why EDTA is the most dominant organic pollutant in surface waters, due to the lack of degradation of certain metal-EDTA complexes.

  2. Anaerobic Biotransformation and Mobility of Pu and of Pu-EDTA

    International Nuclear Information System (INIS)

    Xun, Luying

    2009-01-01

    The enhanced mobility of radionuclides by co-disposed chelating agent, ethylenediaminetetraacetate (EDTA), is likely to occur only under anaerobic conditions. Our extensive effort to enrich and isolate anaerobic EDTA-degrading bacteria has failed. Others has tried and also failed. To explain the lack of anaerobic biodegradation of EDTA, we proposed that EDTA has to be transported into the cells for metabolism. A failure of uptake may contribute to the lack of EDTA degradation under anaerobic conditions. We demonstrated that an aerobic EDTA-degrading bacterium strain BNC1 uses an ABC-type transporter system to uptake EDTA. The system has a periplasmic binding protein that bind EDTA and then interacts with membrane proteins to transport EDTA into the cell at the expense of ATP. The bind protein EppA binds only free EDTA with a Kd of 25 nM. The low Kd value indicates high affinity. However, the Kd value of Ni-EDTA is 2.4 x 10 -10 nM, indicating much stronger stability. Since Ni and other trace metals are essential for anaerobic respiration, we conclude that the added EDTA sequestrates all trace metals and making anaerobic respiration impossible. Thus, the data explain the lack of anaerobic enrichment cultures for EDTA degradation. Although we did not obtain an EDTA degrading culture under anaerobic conditions, our finding may promote the use of certain metals that forms more stable metal-EDTA complexes than Pu(III)-EDTA to prevent the enhanced mobility. Further, our data explain why EDTA is the most dominant organic pollutant in surface waters, due to the lack of degradation of certain metal-EDTA complexes.

  3. {sup 137}Cs, {sup 239+240}Pu concentrations and the {sup 240}Pu/{sup 239}Pu atom ratio in a sediment core from the sub-aqueous delta of Yangtze River estuary

    Energy Technology Data Exchange (ETDEWEB)

    Pan, S.M., E-mail: span@nju.edu.cn [Key Lab of Ministry of Education of Coast and Island Development, Nanjing University, Nanjing 210093 (China); Tims, S.G. [Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia); Liu, X.Y. [Key Lab of Ministry of Education of Coast and Island Development, Nanjing University, Nanjing 210093 (China); Fifield, L.K. [Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia)

    2011-10-15

    A sediment core collected from the sub-aqueous delta of the Yangtze River estuary was subjected to analyses of {sup 137}Cs and plutonium (Pu) isotopes. The {sup 137}Cs was measured using {gamma}-spectrometry at the laboratories at the Nanjing University and Pu isotopes were determined with Accelerator Mass Spectrometry (AMS), measurements made at the Australian National University. The results show considerable structure in the depth concentration profiles of the {sup 137}Cs and {sup 239+240}Pu. The shape of the vertical {sup 137}Cs distribution in the sediment core was similar to that of the Pu. The maximum {sup 137}Cs and {sup 239+240}Pu concentrations were 16.21 {+-} 0.95 mBq/g and 0.716 {+-} 0.030 mBq/g, respectively, and appear at same depth. The average {sup 240}Pu/{sup 239}Pu atom ratio was 0.238 {+-} 0.007 in the sediment core, slightly higher than the average global fallout value. The changes in the {sup 240}Pu/{sup 239}Pu atom ratios in the sediment core indicate the presence of at least two different Pu sources, i.e., global fallout and another source, most likely close-in fallout from the Pacific Proving Grounds (PPG) in the Marshall Islands, and suggest the possibility that Pu isotopes are useful as a geochronological tool for coastal sediment studies. The {sup 137}Cs and {sup 239+240}Pu inventories were estimated to be 7100 {+-} 1200 Bq/m{sup 2} and 407 {+-} 27 Bq/m{sup 2}, respectively. Approximately 40% of the {sup 239+240}Pu inventory originated from the PPG close-in fallout and about 50% has derived from land-origin global fallout transported to the estuary by the river. This study confirms that AMS is a useful tool to measure {sup 240}Pu/{sup 239}Pu atom ratio and can provide valuable information on sedimentary processes in the coastal environment.

  4. Quantitative dissolution of (U, Pu)O2 MOX (0.4% to 44% PuO2) using microwave heating technique

    International Nuclear Information System (INIS)

    Malav, R.K.; Fulzele, Ajit K.; Prakash, Amrit; Afzal, Md.; Panakkal, J.P.

    2011-01-01

    AFFF has fabricated the (U, Pu)O 2 mixed oxide fuels for PHWRs, BWRs, PFBRs and FBTRs. The quantitative dissolution of the fuel samples are required within time for accurate determination of uranium-plutonium in chemical quality control laboratory. This paper describes the use of microwave heating technique in quantitative dissolution of (U, Pu)O 2 MOX (from 0.4% to 44% PuO 2 ). (author)

  5. Estimation of human gonadal Pu and Ce concentrations from animal data

    International Nuclear Information System (INIS)

    Thomas, R.G.; Durbin, P.W.; McInroy, J.F.; Healy, J.W.

    1989-01-01

    Data were obtained from the literature for gonad and body weights and for the Pu or Ce content of the gonads and body at death for several laboratory animal species, five human Pu injection cases, and 731 human adults exposed environmentally to Pu in fallout. Data for Pu concentration in gonads, liver, and bone samples of 59 male and five female occupational Pu cases (including four completely analyzed whole bodies) were obtained from the U.S. Transuranium Registry. A logarithmic function was used to relate fractional Pu or Ce concentration in testes and ovaries to body weight of the animals and to predict fractional Pu or Ce concentrations in human gonads, [Pu]G . PuB-1 = aBWb, where [Pu]G or [Ce]G is the nuclide concentration in gonads (Bq g-1 of wet weight), PuB or CeB is the nuclide content of the body at death, and BW is body weight (kg). The fractional Pu and Ce concentrations in both the testes and ovaries are inverse and nearly linear functions of body weight. The regression lines of fractional Pu or Ce concentration in testes and ovaries have similar slopes (b = -1.07 +/- 0.14); however, the nuclide concentrations (coefficient a) in ovaries are six times greater than in testes. Extrapolation of the animal data yielded fractional Pu concentrations in human testes and ovaries that agree with those calculated for the occupational cases and those recommended by the International Commission on Radiological Protection. The good agreement between the fractional concentrations of Pu and Ce in the testes and in the ovaries suggests that these data can be substituted in metabolic models of chemically similar elements for which gonadal data are scarce

  6. Structural, magnetic, electronic and optical properties of PuC and PuC{sub 0.75}: A hybrid density functional study

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Rong [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China); College of Materials Science and Engineering, Chongqing Jiaotong University, Chongqing 400074 (China); Tang, Bin [School of Business Administration, Chongqing City Management College, Chongqing 401331 (China); Gao, Tao, E-mail: gaotao@scu.edu.cn [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China); Ao, BingYun, E-mail: aobingyun@caep.cn [Science and Technology on Surface Physics and Chemistry Laboratory, P.O. Box 718-35, Mianyang 621907 (China)

    2016-05-15

    We perform first principles calculations to investigate the structural, magnetic, electronic and optical properties of PuC and PuC{sub 0.75}. Furthermore, we examine the influence of carbon non-stoichiometry on plutonium monocarbide. For the treatment of strongly correlated electrons, the hybrid density functionals like PBE0, Fock-0.25 are used and we compare the results with the generalized gradient approximation (GGA), local density approximation (LDA), LDA + U and experimental ones. The optimized lattice constant a{sub 0} = 4.961 Å for PuC in the Fock-0.25 scheme is the most close to the experimental data. The ground states of PuC and PuC{sub 0.75} are found to be anti-ferromagnetic. Our results indicate that additional removal of a C atom make lattice contract and new DOS peak appear in the near-Fermi region. We also compute and compare the optical properties of PuC and PuC{sub 0.75}. The difference in optical properties between PuC and PuC{sub 0.75} should also be the influence of carbon vacancies.

  7. Transport process of Pu isotope in marginal seas of the western North Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Masatoshi [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, Hirosaki, 036-8564, Aomori (Japan); Zheng, Jian [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, 263-8555, Chiba (Japan)

    2014-07-01

    Significant quantities of Pu isotopes have been released into the marine environment as the result of atmospheric nuclear weapons testing. Most radionuclides globally dispersed in atmospheric nuclear weapons testing were released into the environment during the 1950's and 1960's. In the western North Pacific Ocean, the principal source can be further distinguished as two distinct sources of Pu: close-in tropospheric fallout from nuclear weapons testing at the Pacific Proving Grounds (PPG) in the Marshall Islands and global stratospheric fallout. Since the {sup 240}Pu/{sup 239}Pu atom ratio is characteristic for the Pu emission source, information on Pu isotopic signature is very useful to better understand the transport process in the oceans and to identify the sources of Pu. The mean atom ratio of {sup 240}Pu/{sup 239}Pu from the global stratospheric fallout is 0.180 ±0.014 based on soil sample data, whereas that from close-in tropospheric fallout from the PPG is 0.33 - 0.36. The {sup 240}Pu/{sup 239}Pu atom ratios in seawater samples collected in marginal seas of the western North Pacific Ocean will provide important and useful data for understanding the process controlling Pu transport and for distinguishing future Pu sources. The objectives of this study were to measure the {sup 239+240}Pu concentrations and {sup 240}Pu/{sup 239}Pu atom ratios in seawater from the Sea of Okhotsk, Japan Sea, South China Sea and Sulu Sea and to discuss the transport process of Pu. Large-volume seawater samples (250 L each) were collected from the surface to the bottom in marginal seas of the western North Pacific Ocean with acoustically triggered quadruple PVC sampling bottles during the R/V Hakuho-Maru cruise. The {sup 239}Pu and {sup 240}Pu concentrations and {sup 240}Pu/{sup 239}Pu atom ratios were measured with a double-focusing SF-ICP-MS, which was equipped with a guard electrode to eliminate secondary discharge in the plasma and to enhance overall sensitivity. In

  8. Variations in Pu isotopic composition in soils from the Spitsbergen (Norway): Three potential pollution sources of the Arctic region.

    Science.gov (United States)

    Łokas, E; Anczkiewicz, R; Kierepko, R; Mietelski, J W

    2017-07-01

    Although the polar regions have not been industrialised, numerous contaminants originating from human activity are detectable in the Arctic environment. This study reports evidence of 240 Pu/ 239 Pu atomic ratios in the tundra and initial soils from different parts of west and central Spitsbergen and recognizes possible environmental inputs of non-global fallout Pu. The average atomic ratio of 240 Pu/ 239 Pu equal to 0.179 (ranging between 0.129 and 0.201) in tundra soils are comparable to the characteristic ratio for global fallout (0.180). However, the 240 Pu/ 239 Pu atomic ratios in the initial soils from proglacial zone of glaciers change within wide range between 0.1281 and 0.234 with the mean value of 0.169. By combining alpha and mass spectrometry, the three-sources model was used to identify the Pu sources in initial soils. Our study indicated that the main source of Pu is nuclear tests and that a second source with lower Pu ratio may come from weapons grade Pu (unexploded weapons grade Pu ie. material from bomb which didn't undergo nuclear explosions for example for security tests). Additionally, we found samples with high 238 Pu/ 239+240 Pu activity ratios and with typical global fallout 240 Pu/ 239 Pu atomic ratios, which are associated with separate sources of pure 238 Pu from the SNAP-9A satellite burn up in the atmosphere. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Inhaled 239PuO2 in rats with pulmonary emphysema

    International Nuclear Information System (INIS)

    Lundgren, D.L.; Mauderly, J.L.; Hahn, F.F.

    1984-01-01

    The modifying effects of a pre-existing lung disease (emphysema) on the deposition, distribution, retention, and effects of inhaled 239 PuO 2 in the rat are being investigated. Preliminary observations indicated that the deposition and retention patterns for 239 Pu particles inhaled by rats with emphysema and control rats were similar, but the distribution of inhaled 239 Pu immediately after exposure was different. Respiratory function measured through one year after exposure to 239 Pu was consistent with emphysema and was not altered by the 239 Pu lung burden. Long-term observations are continuing. 4 references, 2 tables

  10. Phytoextraction studies for removal of 239Pu using Vetiveria zizanoides plants

    International Nuclear Information System (INIS)

    Singh, Shraddha; Fulzele, D.P.; Kaushik, C.P.

    2015-01-01

    The potential of Vetiveria zizanoides, a plant used for environmental conservation was tested for remediation of radionuclide plutonium ( 239 Pu). While the plant could remediate high levels of 239 Pu (65%) from solutions, remediation of radionuclides from soil was limited. Addition of chelating agents such as citric acid (CA) and diethylenetriaminepentaacetic acid (DTPA) enhanced phytoremediation of 239 Pu from soil. Translocation of 239 Pu to the shoot biomass showed an enhancement in the presence of chelating agents. The present studies have shown that V. zizanoides is a suitable candidate plant for remediation of 239 Pu and addition of DTPA enhanced translocation of radionuclide to shoot which may further lead to phytoextraction. (author)

  11. Effect of Pu-rich agglomerate in MOX fuel on a lattice calculation

    International Nuclear Information System (INIS)

    Kawashima, Katsuyuki; Yamamoto, Toru; Namekawa, Masakazu

    2007-01-01

    The effect of Pu-rich agglomerates in U-Pu mixed oxide (MOX) fuel on a lattice calculation has been demonstrated. The Pu-rich agglomerate parameters are defined based on the measurement data of MIMAS-MOX and the focus is on the highly enriched MOX fuel in accordance with increased burnup resulting in a higher volume fraction of the Pu-rich agglomerates. The lattice calculations with a heterogeneous fuel model and a homogeneous fuel model are performed simulating the PWR 17x17 fuel assembly. The heterogeneous model individually treats the Pu-rich agglomerate and U-Pu matrix, whereas the homogeneous model homogenizes the compositions within the fuel pellet. A continuous-energy Monte Carlo burnup code, MVP-BURN, is used for burnup calculations up to 70 GWd/t. A statistical geometry model is applied in modeling a large number of Pu-rich agglomerates assuming that they are distributed randomly within the MOX fuel pellet. The calculated nuclear characteristics include k-inf, Pu isotopic compositions, power density and burnup of the Pu-rich agglomerates, as well as the pellet-averaged Pu compositions as a function of burnup. It is shown that the effect of Pu-rich agglomerates on the lattice calculation is negligibly small. (author)

  12. Electronic structure of α- and δ-Pu from photoelectron spectroscopy

    International Nuclear Information System (INIS)

    Arko, A. J.; Joyce, J. J.; Morales, L.; Wills, J.; Lashley, J.; Wastin, F.; Rebizant, J.

    2000-01-01

    We report photoemission results on α- and δ-Pu using a laser plasma light source (LPLS) as well as He light as the exciting radiation. The LPLS is a pseudocontinuum tunable light source with intensities rivaling some second-generation synchrotrons. Both phases of Pu display a narrow, temperature-independent, 5f-related feature at the Fermi energy, which is narrower in δ-Pu than in α-Pu, suggestive of possible heavy-fermion-like behavior. In both α-Pu and δ-Pu the photon-energy dependence of this feature suggests some 6d admixture, albeit somewhat smaller in δ-Pu. In this respect it differs qualitatively from Ce and U heavy fermions. (c) 2000 The American Physical Society

  13. Determination of Pu, Am and Cm in Environmental Samples

    Energy Technology Data Exchange (ETDEWEB)

    Lujaniene, G. [SRI Centre for Physical Sciences and Technology, Vilnius (Lithuania)

    2013-07-15

    The determination of actinides in the environmental samples at a lower detection limit is required for monitoring purposes and for environmental research. The method for Pu, Am and Cm measurements in soil and sediment samples provides high recoveries and good decontamination from interfering radionuclides. The main steps of the method involve digestion of the samples, separation of radionuclides from matrix using the TOPO /cyclohexane extraction and final purification using extraction Eichrom resins (TEVA, TRU). The accuracy and precision of Pu, Am and Cm analyses were tested using IAEA RM No 135, NIST SRM No 4350b, No 4357 and in intercomparison runs organized by the Riso National Laboratory, Denmark, and in the proficiency tests organized by National Physical Laboratory, UK. The method was applied for measurement of radionuclides in aerosol samples (ashes {approx}30 g), bottom sediments (50-80 g dr. wt) and soil (including Chernobyl soil) samples. (author)

  14. 238Pu fuel form processes. Savannah River Laboratory monthly report

    International Nuclear Information System (INIS)

    1976-05-01

    Progress in the Savannah River 238 Pu fuel form program is summarized. Suspended solids observed in the technical-grade oxalic acid solution used in H-Area B-Line had no significant effect on particle size or morphology. A small but significant increase in product purity was noted with the use of reagent-grade oxalic acid. The density of hot-pressed LCHP pellets made from both problem and standardized feed decreased with longer milling times as was observed for multi-hundred watt (MHW) pellets. The LCHP pellets (greater than 90 percent theoretical density) generally cracked following final heat treatment. Cold-pressing studies indicate the anticipated pressure variation during cold pressing in the PuFF facility will have negligible effect on the density of MHW spheres. Construction of the plutonium experimental facility is 72 percent complete

  15. Sorption of 237Pu by the diatom Asterionella formosa

    International Nuclear Information System (INIS)

    Conway, H.L.; Wahlgren, M.A.; Peterson, N.; Nelson, D.M.

    1976-01-01

    Knowledge of the behavior of the man-made radionuclide plutonium within aquatic environments is of fundamental importance in assessing its potential hazards and ecological impact. The sorption of plutonium by phytoplankton and other algae is the dominant factor in the biological transport of plutonium in the aquatic environment, and it has been suggested that sorption by phytoplankton may be responsible for the seasonal loss of plutonium from the epilimnion of Lake Michigan. A unialgal diatom culture was spiked with 237 Pu tracer solution in an attempt to simulate the behavior of fallout plutonium observed in field studies. The results were encouraging in that the 237 Pu in the filtered lake water medium exhibited strongly anionic properties similar to fallout plutonium in Lake Michigan, with limited sorption on container walls. The purpose of the present study was to extend the investigations of the sorption of plutonium by phytoplankton in a controlled environment using continuous culture techniques

  16. Simultaneous determination of U and Pu isotopes by alpha spectrometry

    International Nuclear Information System (INIS)

    Equillor, H.E.; Campos, J.M.

    2011-01-01

    Determination of actinides by alpha spectrometry is usually carried out after full separation of each of the components of the sample. The procedure presented in this paper permits U and Pu isotopes to be measured together allowing faster sample processing and measurement. The method consists in the extraction with tributyl phosphate of U and Pu isotopes from the rest of the matrix, followed by a cathodic electrodeposition to obtain alpha spectrometry suitable pieces. It can be applied to various environmental samples, such as water, filters and soil (about 0.5 g of solid sample for the described conditions). High-quality electroplated discs are essential for simultaneous processing, so a technique to achieve this requirement is also explained. (authors) [es

  17. Antioxidant Phenolic Compounds from Pu-erh Tea

    Directory of Open Access Journals (Sweden)

    Shu Shan Du

    2012-11-01

    Full Text Available Eight compounds were isolated from the water extract of Pu-erh tea and their structures were elucidated by NMR and MS as gallic acid (1, (+-catechin (2, (−-epicatechin (3, (−-epicatechin-3-O-gallate (4, (−-epigallocatechin-3-O-gallate (5, (−-epiafzelechin- 3-O-gallate (6, kaempferol (7, and quercetin (8. Their in vitro antioxidant activities were assessed by the DPPH and ABTS scavenging methods with microplate assays. The relative order of DPPH scavenging capacity for these compounds was compound 8 > compound 7 > compound 1 > compound 6 > compound 4 ≈ compound 5 > compound 2 > VC (reference > compound 3, and that of ABTS scavenging capacity was compound 1 > compound 2 > compound 7 ≈ compound 8 > compound 6 > compound 5 > compound 4 > VC (reference > compound 3. The results showed that these phenolic compounds contributed to the antioxidant activity of Pu-erh tea.

  18. Thermodynamic database development: Al-Am-Ga-Pu-U

    Energy Technology Data Exchange (ETDEWEB)

    Perron, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Physical and Life Sciences; Turchi, P. E. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Physical and Life Sciences; Landa, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Physical and Life Sciences; Soderlind, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Physical and Life Sciences

    2014-03-17

    The goal of this study is about the thermodynamic re-assessment of the Plutonium- Uranium (Pu-U) system as a first step leading to the development of a plutonium-based thermodynamic database (i.e., Pu with Al, Am, Ga, Mo, U…) with resulting phase diagrams and associated thermodynamic data. Indeed, phase stability trends and phase diagrams of multi-component nuclear materials are crucial for predicting properties and performance under normal, hypothetical or even accidental conditions. This work is based on a coupling between ab initio energetics, phenomenological thermodynamics models - based on the CALPHAD (CALculation of PHAse Diagrams) approach - and the use of the Thermo-Calc software, together with experimental data (whenever available). The present report summarizes results obtained (quarter period: 10/07/2013-01/07/2014) under the auspices of an agreement between CEA/DAM and NNSA/DP on cooperation in fundamental science supporting stockpile stewardship (P182).

  19. Design of a Pu-238 waste incineration process

    International Nuclear Information System (INIS)

    Charlesworth, D.L.; McCampbell, R.B.

    1985-01-01

    Combustible 238 Pu waste is generated as a result of normal operation and decommissioning activity at the Savannah River Plant and is being retrievably stored at the Plant. As part of the long-term plan to process the stored waste and current waste in preparation for future disposition, a 238 Pu incinceration process is being cold-tested at SRL. The incineration process consists of a continuous-feed preparation system, a two-stage, electrically fired incinerator, and a filtration off-gas system. Process equipment has been designed, fabricated, and installed for nonradioactive testing and cold run-in. Design features to maximize the ability to remotely maintain the equipment were incorporated into the process. Interlock, alarm, and control functions are provided by a programmable controller. Cold testing is scheduled to be completed in 1986

  20. 238Pu - Comments on Evaluation of Decay Data

    International Nuclear Information System (INIS)

    Chechev, V. P.

    2013-01-01

    This evaluation was done originally in March 2003, corrected in June 2004, and then updated in June 2009 with a literature cut-off by the same date. Decay Scheme: The decay scheme is based on 2007Br04. Some expected weak gamma-ray transitions were not observed directly in 238 Pu α-decay but have been adopted from decay of 234 Pa and 234 Np

  1. Time-sensitive Customer Churn Prediction based on PU Learning

    OpenAIRE

    Wang, Li; Chen, Chaochao; Zhou, Jun; Li, Xiaolong

    2018-01-01

    With the fast development of Internet companies throughout the world, customer churn has become a serious concern. To better help the companies retain their customers, it is important to build a customer churn prediction model to identify the customers who are most likely to churn ahead of time. In this paper, we propose a Time-sensitive Customer Churn Prediction (TCCP) framework based on Positive and Unlabeled (PU) learning technique. Specifically, we obtain the recent data by shortening the...

  2. Process for the production of 238Pu16O2

    International Nuclear Information System (INIS)

    Lins, W.

    1976-01-01

    For use as a power source in heart pacers, plutonium dioxide having a naturally occurring oxygen isotope composition is converted into solid phase PuCl 3 which is subsequently oxidized to form plutonium dioxide of the desired isotope composition by means of water vapor, the oxygen component of which consists essentially of the isotope 16 O. Apparatus suited for this purpose is also described

  3. 239 240Pu in Lake Michigan: 1971 to 1978

    International Nuclear Information System (INIS)

    Wahlgren, M.A.; Nelson, D.M.; Orlandini, K.A.; Kucera, E.T.

    1978-01-01

    The plutonium concentration data presented previously have consisted primarily of results from studies of short-term variations, i.e., the annual plutonium cycle conducted at Lake Michigan station ANL-5, 12 km SW of Grand Haven, Michigan. In this report, mean annual concentrations of total plutonium in unfiltered water from far off-shore (> 30 km) stations for the period 1971 through 1977, and from station ANL-5 (1975 through 1978) are summarized to establish the long-term trend in plutonium concentration in Lake Michigan. The results presented show that the mean annual concentration in the water column is similar at ANL-5 and at offshore stations and has decreased at the rate of only 6% per year during the period 1972 through 1978. The nearly constant concentration indicates that steady-state equilibria exist between plutonium inputs to the lake and the loss of plutonium from the water column. Observations suggest the existence of an active redox cycle for Pu in Lake Michigan. In this cycle, Pu IV atoms in solution are continually taken up by particulate materials but may be oxidized within microzones of the particles such as freshly deposited manganese coatings and also in solution by agents such as dissolved oxygen. In turn, the concentration of Pu VI in solution may be limited by reaction with reducing constituents of the coloidal-sized fraction (or decomposer organisms such as bacteria or fungi, which might have been present after filtration) and with planktonic organisms in the environment to produce Pu IV and thus maintain the cycle

  4. Method of recovery of U, Pu and their compounds

    International Nuclear Information System (INIS)

    Cech, B.; Kaderabek, E.; Hanslik, T.

    1977-01-01

    A method is proposed of removing metal sheaths consisting of either Zr or Nb or Ti or an alloy of at least two of the metals from ceramic nuclear fuel based on U or Pu compounds. The system is exposed to hydrogen, preferably at temperatures of 250 to 460 degC and pressures of 20 to 50 at. The resulting zirconium hydride or hydrides of other metals is separated, eg., mechanically. (M.K.)

  5. Dynamic effect analysis in 240Pu fission at low energy

    International Nuclear Information System (INIS)

    Patin, Y.; Lachkar, J.; Sigaud, J.

    1975-01-01

    The variations of kinetic and excitation energies and fragment masses have been analyzed as a function of the fissioning nucleus excitation energy. Most interest has been taken in the fission of 240 Pu where many experimental data have been reported. The results tend, in the whole, to illustrate the existence of two modes of fission; the first one is superfluid, the other is strongly damped in the last stage of the fission process [fr

  6. Plutonium activities and 240Pu/ 239Pu atom ratios in sediment cores from the east China sea and Okinawa Trough: Sources and inventories

    Science.gov (United States)

    Wang, Zhong-liang; Yamada, Masatoshi

    2005-05-01

    Plutonium concentrations and 240Pu/ 239Pu atom ratios in the East China Sea and Okinawa Trough sediment cores were determined by isotope dilution inductively coupled plasma mass spectrometry after separation using ion-exchange chromatography. The results showed that 240Pu/ 239Pu atom ratios in the East China Sea and Okinawa Trough sediments, ranging from 0.21 to 0.33, were much higher than the reported value of global fallout (0.18). The highest 240Pu/ 239Pu ratios (0.32-0.33) were observed in the deepest Okinawa Trough sediment samples. These ratios suggested the US nuclear weapons tests in the early 1950s at the Pacific Proving Grounds in the Marshall Islands were a major source of plutonium in the East China Sea and Okinawa Trough sediments, in addition to the global fallout source. It was proposed that close-in fallout plutonium was delivered from the Pacific Proving Grounds test sites via early direct tropospheric fallout and transportation by the North Pacific Equatorial Circulation system and Kuroshio Current into the Okinawa Trough and East China Sea. The total 239 + 240 Pu inventories in the cores were about 150-200% of that expected from direct global fallout; about 46-67% of the total inventories were delivered from the Pacific Proving Grounds. Much higher 239 + 240 Pu inventories were observed in the East China Sea sediments than in sediments of the Okinawa Trough, because in the open oceans, part of the 239 + 240 Pu was still retained in the water column, and continued Pu scavenging was higher over the margin than the trough. According to the vertical distributions of 239 + 240 Pu activities and 240Pu/ 239Pu atom ratios in these cores, it was concluded that sediment mixing was the dominant process in controlling profiles of plutonium in this area. Faster mixing in the coastal samples has homogenized the entire 240Pu/ 239Pu ratio record today; slightly slower mixing and less scavenging in the Okinawa Trough have left the surface sediment ratios closer

  7. Study of phase equilibria in function of temperature in UO2-PuO2-Pu2O3 system for nuclear ceramics with high plutonium contents

    International Nuclear Information System (INIS)

    Truphemus, Thibaut

    2013-01-01

    In the UO 2 -PuO 2 -Pu 2 O 3 section, a monophasic (U 1-y ,Pu y )O 2-x domain is stable for y≤0,20 at 25 C and up to solid-liquid equilibrium. At higher Pu content, phase equilibria are more unclear with a phase separation process. The main objective of this work consisted in upgrading the representation of this system for 0,15≤y≤0,65 and 25≤T(C)≤1500. At 25 C, a miscibility gap composed by two different (U 1-y ,Pu y )O 2-x phases has been observed for y≤0,45, with one very closed to stoichiometric state (Oxygen/Metal=2) and one other very reduced. For the first time, a triphasic domain has been characterized at higher Pu contents, with two (U 1-y ,Pu y )O 2-x phases near y=0,45 and one (U 1-y ,Pu y ) 2 O 3 phase with a low U content inside. Concerning the study in function of temperature, we have demonstrated that phase separation temperature increase when Pu content grows. Several representations have been established. At 200 C, the representation is closed to that at 25 C. At 400 C, the phase separation have been specified at a lower Pu content than that of literature: y=0,35. At 600 C, our results have clarified the section, until then very unclear, with a phase separation appearing at y=0,60.The microstructural analysis has clearly demonstrated the significant impact of the phase separation on the material. Indeed many cracks have been observed in our samples, and quantity of these defects increases when Pu content grows. (author) [fr

  8. Pu-238 assay performance with the Canberra IQ3 system

    Energy Technology Data Exchange (ETDEWEB)

    Booth, L.; Gillespie, B.; Seaman, G.

    1997-11-01

    Canberra Industries has recently completed a demonstration project at the Westinghouse Savannah River Site (WSRC) to characterize 55-gallon drums containing Pu-238 contaminated waste. The goal of this project was to detect and quantify Pu-238 contaminated waste. The goal of this project was to detect and quantify Pu-238 waste to detection limits of less than 50 nCi/g using gamma assay techniques. This would permit reclassification of these drums from transuranic (TRU) waste to low-level waste (LLW). The instrument used for this assay was a Canberra IQ3 high sensitivity gamma assay system, mounted in a trailer. The results of the measurements demonstrate achievement of detection levels as low as 1 nCi/g for low density waste drums, and good correlation with known concentrations in several test drums. In addition, the data demonstrates significant advantages for using large area low-energy germanium detectors for achieving the lowest possible MDAs for gamma rays in the 80-250 keV range. 1 fig., 2 tabs.

  9. Uso de contraceptivos por puérperas adolescentes

    Directory of Open Access Journals (Sweden)

    Fernanda Schulz da Rosa

    2014-07-01

    Full Text Available Objetivo: Indagar el uso de métodos contraceptivos por las puérperas adolescentes a fin de relacionar su (desuso con el embarazo en la adolescencia. Método: Estudio transversal, descriptivo, realizado por medio de un instrumento estructurado con 181 puérperas adolescentes que tuvieron sus partos en el hospital participante de la investigación. Los datos fueron recolectados en el período de diciembre de 2008 a diciembre de 2009. Resultados: El 64,1% de las puérperas usaba algún método contraceptivo antes del embarazo; los métodos más utilizados fueron el anticoncepcional oral (51% y el preservativo masculino (29%. Para el 75% de las adolescentes el embarazo fue planeado y justificado por el deseo y la voluntad propia de experimentar la maternidad. Conclusión: Considerando que casi la mitad de las adolescentes entrevistadas deseaba el embarazo, se deduce que investigar y discutir apenas el uso o no de los métodos contraceptivos no es adecuado. Es necesario profundizar las investigaciones acerca de los significados de ser madre en la adolescencia.

  10. Direct fabrication of 238PuO2 fuel forms

    International Nuclear Information System (INIS)

    Burney, G.A.; Congdon, J.W.

    1982-07-01

    The current process for the fabrication of 238 PuO 2 heat sources includes precipitation of small particle plutonium oxalate crystals (4 to 6 μm diameter), a calcination to PuO 2 , ball milling, cold pressing, granulation (60 to 125 μm), and granule sintering prior to hot pressing the fuel pellet. A new two-step direct-strike Pu(III) oxalate precipitation method which yields mainly large well-developed rosettes (50 to 100 μm diameter) has been demonstrated in the laboratory and in the plant. These large rosettes are formed by agglomeration of small (2 to 4 μm) crystals, and after calcining and sintering, were directly hot pressed into fuel forms, thus eliminating several of the powder conditioning steps. Conditions for direct hot pressing of the large heat-treated rosettes were determined and a full-scale General Purpose Heat Source pellet was fabricated. The pellet had the desired granule-type microstructure to provide dimensional stability at high temperature. 27 figures

  11. Soil components that influence the chemical behavior of 239Pu

    International Nuclear Information System (INIS)

    Nishita, H.; Hamilton, M.

    1978-08-01

    Soil components that influence the extractability of 239 Pu from an artificially contaminated kaolinitic soil in relation to pH have been examined. This was done by using an equilibrium batch technique with CH 3 COOH--NH 4 OH and HNO 3 --NaOH extracting systems. Soil organic matter and free iron oxides had an appreciable effect depending on the pH and the extracting system. The free silica and alumina and amorphous alumino-silicates had lesser influence. With the untreated soil (control), the CH 3 COOH--NH 4 OH system generally extracted more 239 Pu than did the HNO 3 --NaOH system in the acidic pH range, whereas the latter system extracted markedly greater amounts of it in the alkaline pH range. With the soil from which the organic matter was removed, the CH 3 COOH--NH 4 OH system extracted appreciably greater amounts of 239 Pu than the HNO 3 --NaOH system in the acidic pH range, but there was only little, if any, difference between the two extracting systems in the alkaline pH range. The causes and the implications of these results are discussed

  12. Corrosion of a Pu-doped zirconolite-rich ceramic

    International Nuclear Information System (INIS)

    Bakel, A.J.; Buck, E.C.; Wolf, S.F.; Chamberlain, D.B.; Bates, J.K.; Ebbinghaus, B.B.

    1997-01-01

    As part of a large Pu disposition program, a zirconolite-rich titanate ceramic is being developed at Lawrence Livermore National Laboratory (LLNL) as a possible immobilization material. This same material is being tested at Argonne National Laboratory (ANL). The goal of this study is to describe the corrosion behavior of this ceramic, particularly the release of Pu and Gd, using results from several static corrosion tests (MCC-1, PCT-A, and PCT-B). The release of relatively large amounts of Al, Ba, and Ca in short-term tests (3 day MCC-1 and 7 day PCT-A) indicates that these elements are released from grain boundaries or from highly soluble phases. Results from long-term (28, 98, and 182 day) PCT-B show that the releases of Al, Ba, and Ca decrease with time, the releases of U and Zr increase with time, and that the releases of Cs, Gd, Mo, and Pu remain fairly constant. Formation of alteration phases may lead to the decrease of Ba and Ca in leachate solutions. Due to the heterogeneous nature of the material, the formation of alteration phases, and the inherently low solubility of several elements, no element(s) could be recommended as good markers for the overall corrosion of this ceramic. Data show that, due to the complex nature of this material, the release of each element should be considered separately

  13. Analysis and composition of the first U-Pu charge (0,043 per cent of Pu); Analyse et constitution du 1. jeu U-Pu (0,043 pour cent de Pu)

    Energy Technology Data Exchange (ETDEWEB)

    Brunet, J P; Lapparent, D de; Lourme, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    Checking the homogeneity in the content of plutonium of 0,043 per cent Pu-natural uranium alloy slugs has been made by Pu 240 and U 238 spontaneous fissions neutrons counting. The purpose of the test was to select groups of slugs to be correctly associated into fuel rods for critical experiments. General technic for spontaneous fissions counting, then elaboration of data in view of ranking the slugs are described. Results are given for this particular case. (authors) [French] On a effectue un controle d'homogeneite de teneur en plutonium sur des billettes d'alliage 0,043 pour cent Pu-uranium naturel, par comptage des fissions spontanees du plutonium 240 et de l'uranium 238. Le but du controle etait de permettre une association correcte de ces billettes a l'interieur des elements combustibles destines a servir dans des experiences critiques. On indique la methode generale de comptage des fissions spontanees, puis le depouillement des donnees en vue du classement des barreaux. Les resultats pour ce cas particulier sont donnes dans le rapport. (auteurs)

  14. The controlled-potential coulometric determination of plutonium based upon cerium oxidation and the Pu022+/Pu4+ valency change

    International Nuclear Information System (INIS)

    Phillips, G.; Crossley, D.; Venkataramana, P.

    1977-09-01

    Conditions have been established enabling plutonium to be oxidised quantitatively to the hexavalent state in the working compartment of a controlled-potential coulometric cell using electrogenerated ceric ion or excess ceric nitrate. The excess ceric ion is reduced in situ electrochemically without reduction of the hexavalent plutonium. The plutonium is then determined controlled-potential coulometrically by reduction to Pu 3+ followed by oxidation to Pu 4+ . The first oxidation step is conducted in molar nitric acid solution containing sulphamic acid but the coulometric determination step is conducted in molar sulphuric acid solution. The results obtained in the coulometric determination step were less satisfactory following oxidation with electrogenerated ceric ion rather than with chemically added ceric nitrate. Using the recommended conditions, 6 mg quantities of plutonium can be determined with an accuracy of 100.06% and a precision of 0.12% (coefficient of variation). The behaviour of chromium, manganese and vanadium impurity is reported. (author)

  15. Measurement of 240Pu/239Pu isotopic ratios in soils from the Marshall Islands using ICP-MS.

    Science.gov (United States)

    Muramatsu, Y; Hamilton, T; Uchida, S; Tagami, K; Yoshida, S; Robison, W

    2001-10-20

    Nuclear weapons tests conducted by the United States in the Marshall Islands produced significant quantities of regional or tropospheric fallout contamination. Here we report on some preliminary inductively coupled plasma-mass spectrometry (ICP-MS) measurements of plutonium isolated from seven composite soil samples collected from Bikini, Enewetak and Rongelap Atolls in the northern Marshall Islands. These data show that 240Pu/239Pu isotopic signatures in surface soils from the Marshall Island vary significantly and could potentially be used to help quantify the range and extent of fallout deposition (and associated impacts) from specific weapons tests. 137Cs and 60Co were also determined on the same set of soil samples for comparative purposes.

  16. Measurement of 240Pu/239Pu isotopic ratios in soils from the Marshall Islands using ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Muramatsu, Y.; Uchida, S.; Tagami, K.; Yoshida, S. [Environmental and Toxicological Researches Group, National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, 263-8555 Chiba (Japan); Hamilton, T.; Robison, W. [Health and Ecological Assessment Division, Lawrence Livermore National Laboratory, P.O. Box 808, L-453, 94551-0808 Livermore, CA (United States)

    2001-10-20

    Nuclear weapons tests conducted by the United States in the Marshall Islands produced significant quantities of regional or tropospheric fallout contamination. Here we report on some preliminary inductively coupled plasma-mass spectrometry (ICP-MS) measurements of plutonium isolated from seven composite soil samples collected from Bikini, Enewetak and Rongelap Atolls in the northern Marshall Islands. These data show that 240Pu/239Pu isotopic signatures in surface soils from the Marshall Island vary significantly and could potentially be used to help quantify the range and extent of fallout deposition (and associated impacts) from specific weapons tests. 137Cs and 60Co were also determined on the same set of soil samples for comparative purposes.

  17. Measurement of 240Pu/239Pu isotopic ratios in soils from the Marshall Islands using ICP-MS

    International Nuclear Information System (INIS)

    Muramatsu, Y.; Uchida, S.; Tagami, K.; Yoshida, S.; Hamilton, T.; Robison, W.

    2001-01-01

    Nuclear weapons tests conducted by the United States in the Marshall Islands produced significant quantities of regional or tropospheric fallout contamination. Here we report on some preliminary inductively coupled plasma-mass spectrometry (ICP-MS) measurements of plutonium isolated from seven composite soil samples collected from Bikini, Enewetak and Rongelap Atolls in the northern Marshall Islands. These data show that 240Pu/239Pu isotopic signatures in surface soils from the Marshall Island vary significantly and could potentially be used to help quantify the range and extent of fallout deposition (and associated impacts) from specific weapons tests. 137Cs and 60Co were also determined on the same set of soil samples for comparative purposes

  18. The removal of inhaled 239Pu and 238Pu from beagle dogs by lung lavage and chelation treatment

    International Nuclear Information System (INIS)

    Muggenburg, B.A.; Mewhinney, J.A.; Miglio, J.J.; Slauson, D.O.; McClellan, R.O.

    1976-01-01

    Studies were conducted in beagle dogs to determine the efficiency of treatment by lung lavage and injections of chelating agents in removing inhaled plutonium of varied chemical forms and particle sizes. Polydisperse aerosols of 239 Pu were produced at different temperatures from 325 0 C to 1150 0 C to evaluate the effect of the chemical form of the particles. Aerosols of 238 Pu were produced at 1150 0 C only but were of different particle size or size distributions. Three dogs that inhaled each different plutonium aerosol were treated by lung lavages starting two days after the exposure. Subsequent lavages were performed on days 7, 10, 14, 21, 28, 35, 42, and 49 after exposure. Intravenous injections of 100 mg of diethylenetriaminepentaacetic acid (DTPA) as the calcium salt were given on days 1, 2, 3 and 4 after exposure and twice weekly thereafter to the time of sacrifice, 56 days after exposure. The 10 lung lavages removed from 18 to 49% of the initial lung burden of plutonium. The recovery of plutonium by lavage was similar irrespective of the temperature at which the aerosol was produced, however, lavage recovery decreased somewhat with increasing particle size. The efficacy of DTPA treatment increased with decreasing production temperature of the 239 Pu. Treatment with DTPA was not affected by particle size of the 0.8- and 1.9-μm monodisperse 239 Pu aerosol. The effectiveness of lung lavage decreased as the solubility of the aerosol particles increased whereas the effectiveness of the DTPA treatment increased as the solubility of the inhaled aerosol increased as shown by the lowest temperature aerosol and the aerosol-containing soluble fraction. These findings correlated qualitatively with a 2-hour in-vitro solubility test on the exposure aerosols. (author)

  19. Influence of the allotropic beta to alpha transformation and of oxygen on the distribution of plutonium in Zr-Pu and Ti-Pu dilute alloys

    CERN Document Server

    Languille, A; Remy, C

    1972-01-01

    Ti-Pu, Zr-Pu and Ti-U alloys, annealed above the transformation point, can show major segregation after cooling. The segregations increase with oxygen content. Annealing at high temperatures followed by severe quenching can cause them to disappear. (7 refs).

  20. Perturbation in the 240Pu/239Pu global fallout ratio in local sediment following the nuclear accidents at Thule (Greenland) and Palomares (Spain)

    International Nuclear Information System (INIS)

    Mitchell, P.I.; Vintro, L.L.; Gasco, C.; Sanchez-Cabeza, J.A.

    1995-01-01

    It is well established that the main source of the plutonium found in marine sediments throughout the Northern Hemisphere is global stratospheric fallout, characterized by a typical 240 Pu/ 239 Pu atom ratio of ∼0.18. Measurements of perturbations in this ratio at various sites which had been subjected to close-in fallout, mainly from surface-based testing, has confirmed the feasibility of using this ratio to distinguish plutonium from different fallout sources. In the present study, the 240 Pu/ 239 Pu ratio has been examined in samples of sediment collected at Thule (Greenland) and Palomares (Spain), where accidents involving the release and dispersion of plutonium from fractured nuclear weapons occurred in 1968 and 1966, respectively. The 240 Pu/ 239 Pu ratio was measured by high-resolution alpha spectrometry and spectral deconvolution. The analytical results showed that at Thule the mean 240 Pu/ 239 Pu atom ratio was 0.033±0.004, while at Palomares the equivalent ratio appeared to be significantly higher at 0.056±0.003. Both ratios are consistent with those reported for soils samples at the Nevada site and Nagasaki, and are clearly indicative of weapons-grade plutonium. 27 refs., 1 fig., 2 tabs

  1. Integral data evaluation of stainless steel, 239Pu, 240Pu, and H2O for homogeneous plutonium systems

    International Nuclear Information System (INIS)

    Jenquin, U.P.; Thompson, J.K.; Trapp, T.J.; Kottwitz, D.A.

    1979-08-01

    Theory-experiment correlations of plutonium-fueled systems using ENDF/B cross-section data have discrepancies which could be due to cross-section data, theoretical methods, and/or interpretation of the experiment. Analyses of homogeneous plutonium critical experiments were performed to determine where cross section deficiencies may exist. New thermal cross-section data (0.3 eV) were generated for 239 Pu and 240 Pu capture, fission, and neutrons per fission. Two scattering kernels for hydrogen bound in water were also generated. Calculated values of k/sub eff/ using these new data were compared with corresponding values using ENDF/B-IV data. The results indicate that the 240 Pu resonance data are sufficiently well known for hydrogen-moderated plutonium systems. In systems using stainless steel as structural and/or neutron control, a large fraction of the neutron absorptions occur in the stainless steel. Analyses of several systems containing stainless steel indicate that the uncertainty in calculated values of k/sub eff/ is small using current estimates of the uncertainties in the cross sections. 20 figures, 30 tables

  2. Comparison of Pu metabolism and pulmonary tumors in dogs and rats exposed to 239PuO2

    International Nuclear Information System (INIS)

    Mahaffey, J.A.; Sanders, C.L.; Dagle, G.E.; Park, J.F.

    The dose-effect relationships of dogs and rats exposed by inhalation to 239 PuO 2 were compared to evaluate parameters that may provide a better understanding for extrapolating these laboratory animal results to humans. Comparisons were made on animals with lifetime lung doses between 1400 and 11,000 rad. Parameters compared included survival; Pu clearance and translocation; and time of occurrence, incidence and histopathology of pulmonary tumors. The group means for lifetime dose to lung were not significantly different between dogs and rats, but when survival time was expressed as the percentage of maximum life expectancy (MLE), the mean survival time of dogs was 40% of MLE and of rats was 56% of MLE. Lung tumors were the causes of death in 84% of the dogs and 54% of the rats; the mean survival time to lung tumor was 44% of MLE for dogs, compared to 57% of MLE for rats. Whole-body clearance of plutonium was slower in dogs. More Pu translocated to the thoracic lymph nodes, liver, and skeleton in the dogs than in rats. Estimates of species differences in lung clearance were dependent on the methods of estimating initial lung burden. There were parameters with qualitative and quantitative similarities in dogs and rats. Quantitative differences between species, generally within a factor of two, suggested that more reliable dosimetry estimates are needed to make quantitative extrapolation between species

  3. Contribution to the study of U-Ti and U-Pu-Ti carbides

    International Nuclear Information System (INIS)

    Milet, C.A.

    1968-01-01

    After having discussed the reasons to use (U,Pu) carbides as fast reactor fuel, we examine the influence of the addition of titanium to these carbides. A preliminary study has been done on the system of U-C-Ti and some properties have been measured such as: density, thermal expansion, electrical resistivity, atmospheric corrosion and compatibility with stainless steel. The systems U-Pu-C-Ti (Pu/U + Pu equal to 15 per cent) and U-C-Ti have been found to be very similar. There exists a two phases region (U,Pu)C + TiC, an eutectic between (U,Pu)C and TiC for approximately 15 at %. The solubilities of U + Pu in TiC and of Ti in (U,Pu)C is less than 1 % at. The addition of titanium does not markedly change thermal expansion coefficients of (U,Pu)C. However the resistance to atmospheric corrosion and compatibility with stainless steel is improved. Thermal conductivity, calculated from electrical resistivity, has increased. On the other side, the density of fissile material is lowered. The combination of (U,Pu)C + TiC seems to be the most promising alloy for application as nuclear fuel. (author) [fr

  4. The hematopoietic transcription factor PU.1 regulates RANK gene expression in myeloid progenitors

    International Nuclear Information System (INIS)

    Kwon, Oh Hyung; Lee, Chong-Kil; Lee, Young Ik; Paik, Sang-Gi; Lee, Hyun-Jun

    2005-01-01

    Osteoclasts are bone resorbing cells of hematopoietic origin. The hematopoietic transcription factor PU.1 is critical for osteoclastogenesis; however, the molecular mechanisms of PU.1-regulated osteoclastogenesis have not been explored. Here, we present evidence that the receptor activator of nuclear factor κB (RANK) gene that has been shown to be crucial for osteoclastogenesis is a transcriptional target of PU.1. The PU.1 -/- progenitor cells failed to express the RANK gene and reconstitution of PU.1 in these cells induced RANK expression. Treatment of the PU.1 reconstituted cells with M-CSF and RANKL further augmented the RANK gene expression. To explore the regulatory mechanism of the RANK gene expression by PU.1, we have cloned the human RANK promoter. Transient transfection assays have revealed that the 2.2-kb RANK promoter was functional in a monocyte line RAW264.7, whereas co-transfection of PU.1 transactivated the RANK promoter in HeLa cells. Taken together, these results suggest that PU.1 regulates the RANK gene transcription and this may represent one of the key roles of PU.1 in osteoclast differentiation

  5. Pu-erh Tea Inhibits Tumor Cell Growth by Down-Regulating Mutant p53

    Science.gov (United States)

    Zhao, Lanjun; Jia, Shuting; Tang, Wenru; Sheng, Jun; Luo, Ying

    2011-01-01

    Pu-erh tea is a kind of fermented tea with the incorporation of microorganisms’ metabolites. Unlike green tea, the chemical characteristics and bioactivities of Pu-erh tea are still not well understood. Using water extracts of Pu-erh tea, we analyzed the tumor cell growth inhibition activities on several genetically engineered mouse tumor cell lines. We found that at the concentration that did not affect wild type mouse embryo fibroblasts (MEFs) growth, Pu-erh tea extracts could inhibit tumor cell growth by down-regulated S phase and cause G1 or G2 arrest. Further study showed that Pu-erh tea extracts down-regulated the expression of mutant p53 in tumor cells at the protein level as well as mRNA level. The same concentration of Pu-erh tea solution did not cause p53 stabilization or activation of its downstream pathways in wild type cells. We also found that Pu-erh tea treatment could slightly down-regulate both HSP70 and HSP90 protein levels in tumor cells. These data revealed the action of Pu-erh tea on tumor cells and provided the possible mechanism for Pu-erh tea action, which explained its selectivity in inhibiting tumor cells without affecting wild type cells. Our data sheds light on the application of Pu-erh tea as an anti-tumor agent with low side effects. PMID:22174618

  6. Pb-210 and Pu-239,240 in nearshore Gulf of Mexico sediments

    International Nuclear Information System (INIS)

    Rotter, R.J.

    1985-05-01

    Pb-210, Ra-226, and Pu-239,240 activities were measured in nearshore Gulf of Mexico sediments. Sediment cores were collected from the Mississippi delta, and the western Gulf of Mexico shelf. Mississippi delta cores which exhibit significantly higher sedimentation rates show larger inventories of Pb-210. The measured Pu levels from the western shelf are lower than from the delta at comparable depths. In three of the western shelf cores, the observed Pu inventory is considerably less than predicted from atmospheric flux. Therefore, Pu is not being removed to the sediment, or is being released following deposition. A key difference between these isotopes is that Pu exists in a less particle-reactive state. The ratio of excess Pb-210 to Pu levels increases with water depth in the delta and the western shelf. Water depth acts as an integrator of depth-sensitive processes. Pu scavenging is more sensitive to these processes. A sub-surface Pu maximum has been observed. Excess Pb-210 and Pu levels correlate well with sedimentation rates. This suggests that particle flux is important in removal of Pb-210 and Pu to the sediment. The flux of Mn out of the sediment is correlated with inventory data, suggesting that redox cycling of Mn may play a role in increasing Pb-210 and Pu sediment inventories. It is unclear whether the effects of increased sedimentation rates and increased Mn fluxes can be evaluated independently. Mixing of surface sediment correlates with inventory data. Increased sediment mixing allows for additional scavenging of Pb-210 and Pu from overlying waters. Mixing of sediment at depths below the mixed surface layer may play a role in increasing sediment inventories of Pb-210 and Pu

  7. Electrochemical investigations of Pu(IV)/Pu(III) redox reaction using graphene modified glassy carbon electrodes and a comparison to the performance of SWCNTs modified glassy carbon electrodes

    International Nuclear Information System (INIS)

    Gupta, Ruma; Gamare, Jayashree; Sharma, Manoj K.; Kamat, J.V.

    2016-01-01

    Highlights: • First report of aqueous electrochemistry of Plutonium on graphene modified electrode. • Graphene is best electrocatalytic material for Pu(IV)/Pu(III) redox couple among the reported modifiers viz. reduced graphene oxide (rGO) and SWCNT’s. • The electrochemical reversibility of Pu(IV)/Pu(III) redox couple improves significantly on graphene modified electrode compared to previously reported rGO & SWCNTs modified electrodes • Donnan interaction between plutonium species and graphene surface offers a possibility for designing a highly sensitive sensor for plutonium • Graphene modified electrode shows higher sensitivity for the determination of plutonium compared to glassy carbon and single walled carbon nanotube modified electrode - Abstract: The work reported in this paper demonstrates for the first time that graphene modified glassy carbon electrode (Gr/GC) show remarkable electrocatalysis towards Pu(IV)/Pu(III) redox reaction and the results were compared with that of single-walled carbon nanotubes modified GC (SWCNTs/GC) and glassy carbon (GC) electrodes. Graphene catalyzes the exchange of current of the Pu(IV)/Pu(III) couple by reducing both the anodic and cathodic overpotentials. The Gr/GC electrode shows higher peak currents (i p ) and smaller peak potential separation (ΔE p ) values than the SWCNTs/GC and GC electrodes. The heterogeneous electron transfer rate constants (k s ), charge transfer coefficients (α) and the diffusion coefficients (D) involved in the electrocatalytic redox reaction were determined. Our observations show that graphene is best electrocatalytic material among both the SWCNTs and GC to study Pu(IV)/Pu(III) redox reaction.

  8. Roles of PU.1 in monocyte- and mast cell-specific gene regulation: PU.1 transactivates CIITA pIV in cooperation with IFN-gamma.

    Science.gov (United States)

    Ito, Tomonobu; Nishiyama, Chiharu; Nakano, Nobuhiro; Nishiyama, Makoto; Usui, Yoshihiko; Takeda, Kazuyoshi; Kanada, Shunsuke; Fukuyama, Kanako; Akiba, Hisaya; Tokura, Tomoko; Hara, Mutsuko; Tsuboi, Ryoji; Ogawa, Hideoki; Okumura, Ko

    2009-07-01

    Over-expression of PU.1, a myeloid- and lymphoid-specific transcription factor belonging to the Ets family, induces monocyte-specific gene expression in mast cells. However, the effects of PU.1 on each target gene and the involvement of cytokine signaling in PU.1-mediated gene expression are largely unknown. In the present study, PU.1 was over-expressed in two different types of bone marrow-derived cultured mast cells (BMMCs): BMMCs cultured with IL-3 plus stem cell factor (SCF) and BMMCs cultured with pokeweed mitogen-stimulated spleen-conditioned medium (PWM-SCM). PU.1 over-expression induced expression of MHC class II, CD11b, CD11c and F4/80 on PWM-SCM-cultured BMMCs, whereas IL-3/SCF-cultured BMMCs expressed CD11b and F4/80, but not MHC class II or CD11c. When IFN-gamma was added to the IL-3/SCF-based medium, PU.1 transfectant acquired MHC class II expression, which was abolished by antibody neutralization or in Ifngr(-/-) BMMCs, through the induction of expression of the MHC class II transactivator, CIITA. Real-time PCR detected CIITA mRNA driven by the fourth promoter, pIV, and chromatin immunoprecipitation indicated direct binding of PU.1 to pIV in PU.1-over-expressing BMMCs. PU.1-over-expressing cells showed a marked increase in IL-6 production in response to LPS stimulation in both IL-3/SCF and PWM-SCM cultures. These results suggest that PU.1 overproduction alone is sufficient for both expression of CD11b and F4/80 and for amplification of LPS-induced IL-6 production. However, IFN-gamma stimulation is essential for PU.1-mediated transactivation of CIITA pIV. Reduced expression of mast cell-related molecules and transcription factors GATA-1/2 and up-regulation of C/EBPalpha in PU.1 transfectants indicate that enforced PU.1 suppresses mast cell-specific gene expression through these transcription factors.

  9. Reaction kinetics of irradiation prepolymerized MMA-PU IPN by 5DXC FTIR

    International Nuclear Information System (INIS)

    Wu Yiming; Zhang Zhiping; Luo Ning

    2000-01-01

    The reaction kinetics of irradiation-prepolymerized MMA-PU (polyether) IPNs have been studied by FTIR. The results indicate that the polymerization of each component in the IPN follows its normal distinct reaction mechanism with no mutual interference. Increasing the concentration of TMPTAM (crosslinking agent of PMMA) increased the formation rate of PMMA, while the formation rate of PU networks remained almost the same. Increasing the concentration of TMP (crosslinking agent of PU) increased the formation rate of PU, while the formation rate of PMMA networks decreased. The formation rate of PU was obviously faster than that of PMMA. A theory for the cage effect of the PU network has been proposed. (author)

  10. Chemical thermodynamic representation of (U, Pu, Am)O2-x

    International Nuclear Information System (INIS)

    Osaka, Masahiko; Namekawa, Takashi; Kurosaki, Ken; Yamanaka, Shinsuke

    2005-01-01

    The oxygen potential isotherms of (U, Pu, Am)O 2-x were represented by a chemical thermodynamic model proposed by Lindemer et al. It was assumed in the present model that (U, Pu, Am)O 2-x consisted of the chemical species [UO 2 ], [PuO 2 ], [Pu 4/3 O 2 ], [AmO 2 ] and [Am 5/4 O 2 ] in a pseudo-quaternary system by treating the reduction rates of Pu and Am as identical; furthermore an interaction between [Am 5/4 O 2 ] and [UO 2 ] was introduced. The agreement between analytical and experimental isotherms was good, but the analytical values slightly overestimated the experimental values especially in the case of lower Am content. Adding an interaction between [Am 5/4 O 2 ] and [PuO 2 ] to the model resulted in a better representation

  11. Interatomic potentials for PuC by Chen–Möbius multiple lattice inversion

    International Nuclear Information System (INIS)

    Huang, H.; Meng, D.Q.; Lai, X.C.; Li, G.; Long, Y.

    2013-01-01

    The atomic interactions of PuC with B1 structure were described by Chen–Möbius lattice inversion combined with first-principle calculations. In order to obtain the inversion potential parameters of PuC, three different structures including two virtual crystals were built and the Morse function plus a modified term was adopted to fit the pair-potential curves. The reliability of the inversion potential was tested by checking the stability of the transition of PuC from disordered to ordered state and comparing the calculated and experimental physical and thermal properties of PuC. All the results show that the inversion potential could give a stable and accurate description of the atomic interactions in PuC and the physical and thermal properties of PuC are well reproduced by the potential

  12. Fabrication of gamma sources using the neutron-gamma reactions of 238Pu13C

    International Nuclear Information System (INIS)

    Solinhac, I.; Maillard, C.; Donnet, L.

    2004-01-01

    A production campaign for 238 Pu 13 C sources with gamma fluence ranging from 2500 to 4500 gamma/s/4π at 6.13 MeV was carried out in 2002 in Atalante. An experimental study was undertaken to prepare the 238 PuC mixture, which is the most delicate step. This procedure is described together with the other steps in the source fabrication process: purification of a plutonium oxide batch, preparation of a nitric solution of 238 Pu, measurement of the gamma fluence of the PuC mixture before and after insertion into each of the two stainless steel capsules that constitute a PuN 2 O package, welding of the second envelope followed by leak testing, final measurement of the gamma fluence of the sealed source. This PuC sources fabrication procedure is effective: all the sources include the required gamma activity with an uncertainty on the gamma fluence of less than 10%. (authors)

  13. Hematological responses after inhaling 238PuO2: An extrapolation from beagle dogs to humans

    International Nuclear Information System (INIS)

    Scott, B.R.; Muggenburg, B.A.; Welsh, C.A.; Angerstein, D.A.

    1994-01-01

    The alpha emitter plutonium-238 ( 238 Pu), which is produced in uranium-fueled, light-water reactors, is used as a thermoelectric power source for space applications. Inhalation of a mixed oxide form of Pu is the most likely mode of exposure of workers and the general public. Occupational exposures to 238 PuO 2 have occurred in association with the fabrication of radioisotope thermoelectric generators. Organs and tissue at risk for deterministic and stochastic effects of 238 Pu-alpha irradiation include the lung, liver, skeleton, and lymphatic tissue. Little has been reported about the effects of inhaled 238 PuO 2 on peripheral blood cell counts in humans. The purpose of this study was to investigate hematological responses after a single inhalation exposure of Beagle dogs to alpha-emitting 238 PuO 2 particles and to extrapolate results to humans

  14. Toxicity of inhaled 238PuO2 I

    International Nuclear Information System (INIS)

    Diel, J.H.; Mewhinney, J.A.

    1980-01-01

    The deposition, retention, translocation and microscopic distribution of inhaled 238 PuO 2 particles were studied to better define the organs at risk and uniformity of dose and cell types or structures at risk in the lung. Beagle dogs were exposed once by inhalation to an aerosol of 238 PuO 2 with particle aerodynamic diameters of 0.7, 1.4, or 2.7 μm (+-10%). Initial burdens averaged about 700 nCi, a level not expected to induce life-shortening effects in Beagle dogs. Animals were sacrificed at times from 4 hours to 2 years after exposure. Whole body retention of plutonium and its distribution among organs in the sacrificed animals was determined by radiochemical analysis for plutonium content of excreta and tissue samples. The distribution of particles in lung was determined using autoradiographs of lung tissue sections and computer-assisted data collection and analysis. Soon after exposure, PuO 2 was relatively insoluble in lung with individual particles being randomly distributed throughout the lung. A distinct change in the rate of dissolution from lung occurred at about 100 days after exposure resulting in decreased pulmonary retention and increased uptake by liver and skeleton. Particle breakup was observed in autoradiographs for time periods in excess of 128 days after exposure. Broken up particles dissolved rapidly leaving little residue in the lung. The remaining particles were randomly distributed in the lung. These results are discussed in relation to current radiation protection guides for plutonium radionuclides. (author)

  15. Sequential determination of {sup 239,240}Pu, {sup 238} Pu, {sup 241} Am and {sup 90}Sr in radioactive wastes using SPE sorbents Analig Pu02, AnaLig Sr01 and TRU Resin; Sekvencne stanovenie {sup 239,240}Pu, {sup 238} Pu, {sup 241} Am a {sup 90}Sr v radioaktivnych odpadoch pouzitim SPE sorbentov Analig Pu02, AnaLig Sr01 a TRU Resin

    Energy Technology Data Exchange (ETDEWEB)

    Durkot, E; Dulanska, S [Univerzita Komenskeho v Bratislave, Prirodovedecka fakulta, Katedra jadrovej chemie, 84215 Bratislava (Slovakia)

    2012-04-25

    A simple and rapid method of the sequential determination of radionuclides {sup 239,240}Pu, {sup 238} Pu, {sup 241} Am and {sup 90}Sr in radioactive sludge from the NPP Bohunice A1 with high radiochemical yields and efficient removal of interfering components from a matrix was developed. Separation method combines SPE sorbents Analig Pu02, AnaLig Sr01 made by IBC Advanced Technologies and TRU Resin (Eichrom Technologies) placed in tandem. Advantage of a single-stage column located on the vacuum box with a rapid flow is an effective pre-concentration and separation of radionuclides and minimization of sample separation time. (authors)

  16. Mechanical behaviour of δ-phase Pu-Ga alloys

    International Nuclear Information System (INIS)

    Kaschner, G.C.; Stout, M.G.; Hecker, S.S.

    2007-01-01

    Paper describes a model to ensure prediction of the mechanical behaviour of gallium stabilized plutonium FCC-alloys representing the mechanical threshold strength (MSS) constitutive model based on the effect of temperature, of strain rate, of grain size and of alloy composition. One performed the comparative analysis of the design data derived by means of the elaborated mathematical techniques and of the published results of the mechanical tests of Pu-Ga system various alloys. The model is shown to be adequate to predict the tensile strength and the yield strength values [ru

  17. Preliminary results for complexation of Pu with humic acid

    Energy Technology Data Exchange (ETDEWEB)

    Guczi, J.; Szabo, G. [National Research Inst. for Radiobiology and Radiohygi ene, Budapest, H-1775 (Hungary)]. e-mail: guczi@hp.osski.hu; Reiller, P. [CEA, CE Sac lay, Nuclear Energy Division/DPC/SERC, Laboratoire de Speciation des Radionuclei des et des Molecules, F-91191 Gif-sue-Yvette (France); Bulman, R.A. [Radiation Protection Division Division, Health Protection Agency, Chilton, Didcot (United Kingdom); Geckeis, H. [FZK - Inst. fuer Nukleare Entsorgung, Karlsruhe (Germany)

    2007-06-15

    Interaction of plutonium with humic substances has been investigated by a batch method use of the surface bound humic acid from perchlorate solutions at pH 4-6. By using these novel solid phases, complexing capacities and interaction constants are obtained. The complexing behavior of plutonium is analyzed. Pu(IV)-humate conditional stability constants have been evaluated from data obtained from these experiments by using non-linear regression of binding isotherms. The results have been interpreted in terms of complexes of 1:1 stoichiometry.

  18. Neutron producing reactions in PuBe neutron sources

    Energy Technology Data Exchange (ETDEWEB)

    Bagi, János [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU) (Germany); Lakosi, László; Nguyen, Cong Tam [Centre for Energy Research, Hungarian Academy of Sciences, Budapest (Hungary)

    2016-01-01

    There are a plenty of out-of-use plutonium–beryllium neutron sources in Eastern Europe presenting both nuclear safeguards and security issues. Typically, their actual Pu content is not known. In the last couple of years different non-destructive methods were developed for their characterization. For such methods detailed knowledge of the nuclear reactions taking place within the source is necessary. In this paper we investigate the role of the neutron producing reactions, their contribution to the neutron yield and their dependence on the properties of the source.

  19. Bulk media assay using backscattered Pu-Be neutrons

    CERN Document Server

    Csikai, J

    1999-01-01

    Spectral yields of elastically backscattered Pu-Be neutrons measured for graphite, water, polyethylene, liquid nitrogen, paraffin oil, SiO sub 2 , Al, Fe, and Pb slabs show a definite correlation with the energy dependence of the elastic scattering cross sections, sigma sub E sub L (E sub n). The C, N and O can be identified by the different structures in their sigma sub E sub L (E sub n) functions. The integrated spectral yields versus thickness exhibit saturation for each sample. The interrogated volume is limited by the presence of hydrogen in the sample. (author)

  20. Preliminary tests on the Pu(IV)-polymers

    International Nuclear Information System (INIS)

    Cauchetier, P.; Guichard, C.

    1983-02-01

    It is possible to obtain polymeric species from acid solutions of plutonium by water dilution or slow neutralization. In those two processes the heating improves the polymerization. We describe the conditions of these compounds formation when steam injected in low-acid nitric solutions. The soluble Pu(IV)-polymers are not absorbed by cation-exchangers. They have a well-characterized absorbance spectrum different from that of ionic species. They are stable even after the dilution in the same medium. Inversely, the change of medium including the acidification is able to induce the hydroxide precipitation [fr

  1. DOE plutonium disposition study: Pu consumption in ALWRs

    International Nuclear Information System (INIS)

    1993-01-01

    The Department of Energy (DOE) has contracted with Asea Brown Boveri-Combustion Engineering (ABB-CE) to provide information on the capability of ABB-CE's System 80 + Advanced Light Water Reactor (ALWR) to transform, through reactor burnup, 100 metric tonnes (MT) of weapons grade plutonium (Pu) into a form which is not readily useable in weapons. This information is being developed as part of DOE's Plutonium Disposition Study, initiated by DOE in response to Congressional action. This document Volume 2, provides a discussion of: Plutonium Fuel Cycle; Technology Needs; Regulatory Considerations; Cost and Schedule Estimates; and Deployment Strategy

  2. Source identification of Pu and 236U deposited on Norwegian territories

    OpenAIRE

    Wendel, Cato Christian

    2013-01-01

    Plutonium (Pu) is a predominately anthropogenic element produced during neutron irradiation of U in reactors and nuclear weapon detonations. Pu has been released to the environment during nuclear weapon detonations, nuclear reactor accidents, and in association with reprocessing of spent nuclear fuel. The most important source of Pu in the environment were the 543 atmospheric nuclear detonations conducted worldwide in the period 1945 – 1980 by the former Soviet Union (FSU), USA, United Kingdo...

  3. The use of ultrafiltration for the clean-up of alkaline Pu containing effluents

    International Nuclear Information System (INIS)

    Biddle, P.; Gutman, R.G.

    1983-07-01

    Ultrafiltration has been used to clean up low level Pu solutions at high pH. The decontamination factors achieved were greater than 1000 and were significantly higher than those attained by sedimentation or centrifugation. The results confirmed the findings of earlier work based on the use of Th as a simulant for Pu. A preliminary flowsheet for the decontamination of Pu oxalate liquors is proposed. (author)

  4. A 233U/236U/242Pu/244Pu spike for isotopic and isotope dilution analysis by mass spectrometry with internal calibration

    International Nuclear Information System (INIS)

    Stepanov, A.; Belyaev, B.; Buljanitsa, L.

    1989-11-01

    The Khlopin Radium Institute prepared on behalf of the IAEA a synthetic mixture of 233 U, 236 U, 242 Pu and 244 Pu isotopes. The isotopic composition and elemental concentration of uranium and plutonium were certified on the basis of analyses done by four laboratories of the IAEA Network, using mass spectrometry with internal standardization. The certified values for 233 U/ 236 U ratio and the 236 U chemical concentration have a coefficient of variation of 0.05%. The latter is fixed by the uncertainty in the 235 U/ 238 U ratio of NBS500 used as internal standard. The coefficients of variation of the 244 Pu/ 242 Pu ratio and the 242 Pu chemical concentration are respectively 0.10% and 0.16% and limited by the uncertainty in the 240 Pu/ 239 Pu ratio of NBS947. This four isotope mixture was used as an internal standard as well as a spike, to analyze 30 batches of LWR spent fuel solutions. The repeatability of the mass spectrometric measurements have a coefficient of variation of 0.025% for the uranium concentration, and of 0.039% for the plutonium concentration. The spiking and treatment errors had a coefficient of variation of 0.048%. (author). Refs, figs and tabs

  5. Association of 239Pu with lysosomes in rat, Syrian hamster, and Chinese hamster liver as studied by carrier-free electrophoresis and electron microscopic autoradiography with 241Pu

    International Nuclear Information System (INIS)

    Seidel, A.; Krueger, E.W.; Wiener, M.; Hotz, G.; Balani, M.; Thies, W.G.

    1985-01-01

    The binding of injected monomeric plutonium in the liver of rats, Syrian hamsters, and Chinese hamsters (species which show profound differences in their ability to eliminate 239 Pu from the liver) was investigated by carrier-free electrophoresis using 239 Pu and electron microscopic autoradiography with 241 Pu. These studies are part of a program designed to obtain a better understanding of the mechanisms of the clearance of transuranium elements from liver of different mammals and man. Between 4 and 9 days after nuclide injection, a clear correlation between the majority of the 239 Pu and lysosomal enzymes was observed when the mitochondrial-lysosomal (ML) fraction of the livers was analyzed by carrier-free electrophoresis. In the two hamster species, a second 239 Pu peak exists from the beginning and increases with time to comprise 50% of the total radioactivity at later times. During electron microscopic examination 4 days after 241 Pu injection, beta tracks were frequently observed over globular structures resembling dense bodies in Chinese hamster liver. They were also observed frequently over chromatin-rich portions of the cell nuclei. These results, together with those from previous density gradient studies, show that lysosomes are the primary deposition site for 239 Pu in the liver cytoplasm of these three rodent species. The hypothesis of a morphologic transformation of these lysosomes with time in hamster liver and of rapid bulk exocytosis of the lysosomes in rats are still possible explanations for the extreme differences in the elimination among the three species

  6. Simulation of 239Pu location in trabecular bone: a computerized model of adult endosteal bone remodeling and its interaction with injected 239Pu

    International Nuclear Information System (INIS)

    Kimmel, D.B.; Jee, W.S.S.

    1979-01-01

    A computer simulation of the relationship of bone microanatomic metabolic activity to the microscopic location of 239 Pu in bone has been attempted. The model incorporates the rate of bone turnover, cell location and density, bone resorptive activity (as it removes 239 Pu from bone), bone formation activity (as it buries 239 Pu in bone), recycling of 239 Pu, and liver translocation of 239 Pu to bone, such that the skeletal retention curve for 239 Pu injected in monomeric form into the young adult beagle is matched. The eventual aim of this work is to calculate the radiation dose to bone cells, knowing the relative location of 239 Pu deposited in bone and the cells that reside at bone surfaces as it changes throughout the lifespan of an animal. Early results indicate that osteosarcoma incidence may be proportional to the number of alpha hits which occur to osteoprogenitor cells and osteoblasts, the dividing cell population found near surfaces where bone turnover is in progress

  7. Measurement of oxygen chemical diffusion in PuO{sub 2-x} and analysis of oxygen diffusion in PuO{sub 2-x} and (Pu,U)O{sub 2-x}

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Masato; Uchida, Teppei [Advanced Nuclear System Research and Development Directorate, Japan Atomic Energy Agency, 4-33 Muramatsu, Tokai-mura, Ibaraki 319-1194 (Japan); Sunaoshi, Takeo [Inspection Development Company Ltd., 4-33 Muramatsu, Tokai-mura, Ibaraki 319-1194 (Japan)

    2013-02-15

    Oxygen chemical diffusion in PuO{sub 2-x} was investigated in the temperature range of 1473-1873 K by thermogravimetry as functions of oxygen-to-metal (O/M) ratios and temperatures. The oxygen chemical diffusion coefficients, D were determined assuming that the reduction curves were dominated by a diffusion process. The O/M ratio and Pu content dependence on the chemical diffusion coefficients were evaluated. The chemical diffusion coefficient had its minimum value at around O/M=1.98 and decreased with increasing Pu content in (U,Pu)O{sub 2-x}. The self-diffusion coefficients were evaluated. A model for describing the relationship among O/M ratio, oxygen chemical diffusion, and self-diffusion was proposed based on defect chemistry. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. Measurement of oxygen chemical diffusion in PuO2-x and analysis of oxygen diffusion in PuO2-x and (Pu,U)O2-x

    International Nuclear Information System (INIS)

    Kato, Masato; Uchida, Teppei; Sunaoshi, Takeo

    2013-01-01

    Oxygen chemical diffusion in PuO 2-x was investigated in the temperature range of 1473-1873 K by thermogravimetry as functions of oxygen-to-metal (O/M) ratios and temperatures. The oxygen chemical diffusion coefficients, D were determined assuming that the reduction curves were dominated by a diffusion process. The O/M ratio and Pu content dependence on the chemical diffusion coefficients were evaluated. The chemical diffusion coefficient had its minimum value at around O/M=1.98 and decreased with increasing Pu content in (U,Pu)O 2-x . The self-diffusion coefficients were evaluated. A model for describing the relationship among O/M ratio, oxygen chemical diffusion, and self-diffusion was proposed based on defect chemistry. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. Overview of advanced technologies for stabilization of 238Pu-contaminated waste

    International Nuclear Information System (INIS)

    Ramsey, K.B.; Foltyn, E.M.; Heslop, J.M.

    1998-02-01

    This paper presents an overview of potential technologies for stabilization of 238 Pu-contaminated waste. Los Alamos National Laboratory (LANL) has processed 238 PuO 2 fuel into heat sources for space and terrestrial uses for the past several decades. The 88-year half-life of 238 Pu and thermal power of approximately 0.6 watts/gram make this isotope ideal for missions requiring many years of dependable service in inaccessible locations. However, the same characteristic which makes 238 Pu attractive for heat source applications, the high Curie content (17 Ci/gram versus 0.06 Ci/gram for 239 Pu ), makes disposal of 238 Pu-contaminated waste difficult. Specifically, the thermal load limit on drums destined for transport to the Waste Isolation Pilot Plant (WIPP), 0.23 gram per drum for combustible waste, is impossible to meet for nearly all 238 Pu-contaminated glovebox waste. Use of advanced waste treatment technologies including Molten Salt Oxidation (MSO) and aqueous chemical separation will eliminate the combustible matrix from 238 Pu-contaminated waste and recover kilogram quantities of 238 PuO 2 from the waste stream. A conceptual design of these advanced waste treatment technologies will be presented

  10. Determination of radionuclides {sup 90}Sr, {sup 239,240} Pu, {sup 238}Pu and {sup 241}Am in soil using methods of extraction chromatography and coprecipitation; Stanovenie radionuklidov {sup 90}Sr, {sup 239,240}Pu, : 2{sup 38}Pu a {sup 241}Am v pode vyuzivajuce metody extrakcnej chromatografie a spoluzrazania

    Energy Technology Data Exchange (ETDEWEB)

    Gardonova, V.; Dulanska, S.; Bilohuscin, J. [Univerzita Komenskeho, Prirodovedecka fakulta, Katedra jadrovej chemie, 84215 Bratislava (Slovakia)

    2013-04-16

    Ecosystems, which include soil and sediments, contain not only natural radionuclides but also radionuclides from deposits, mainly {sup 137}Cs, {sup 90}Sr and {alpha}-emitting radionuclides such as {sup 239,240}Pu, {sup 238}Pu and {sup 241}Am, that originate from global fallout and nuclear facilities leaks worldwide. The goal of the work was optimization of separation and determination of {sup 90}Sr, {sup 238}Pu, {sup 239,240}Pu and {sup 241}Am in soil from Slovak Republic. The newest methods were applied for separation of selected radionuclides based on coprecipitation with oxalic salts and extraction chromatography using selective commercial sorbents. (authors)

  11. Adsorption of Pu(IV) Polymer onto 304L Stainless Steel

    International Nuclear Information System (INIS)

    Bronikowski, M.G.

    1999-01-01

    'The report, Technical Basis for Safe Operations with Pu-239 Polymer in NMS and S Operating Facilities (F and H Areas), (WSRC-TR-99-00008) was issued in an effort to upgrade the Authorization Basis (AB) for H Area facilities relative to nuclear criticality. At the time, insufficient data were found in the literature to quantify the adsorption of Pu polymer onto the surfaces of stainless steel tanks. Additional experimental or literature information on the adsorption of Pu(IV) polymer and its removal was deemed necessary to support the H Area AB. The results obtained are also applicable to processing in F Area facilities.Additional literature sources suggest that adsorption on the tank walls should not be a safety concern. The sources show that the amount of Pu polymer that adsorbs from a solution comes to a limiting amount in 5 to 7 days after which no additional Pu is adsorbed. Adsorption increases with Pu concentration and decreases with acid concentration. The adsorbed amounts are small varying from 0.5 mg/cm2 for a 0.5 g/l Pu / 0.5M HNO3 solution to 11 mg/cm2 for a 1-3 g/l Pu / 0.1M HNO3 solution. Additionally, acid concentrations greater than 0.1M will remove a percentage of adsorbed Pu.The experimental results have generally confirmed much of what has been reported in the literature. Specifically, adsorption onto stainless steel was found to increase with increased Pu concentration, and decreased acid concentration. The amount adsorbed was found to come to a limiting amount after 5 to 7 days. Pu adsorbed as polymer was found to be harder to remove than if it was adsorbed as Pu(IV). The amount of Pu adsorbed as polymer was found to be almost an order of magnitude more than that from a similar concentration Pu(IV) solution. Unlike the literature, only a slight increase in adsorption values was found when the steel surface was removed, dried, and replaced in the Pu solution. The amount of Pu as polymer which would adsorb onto the surface of a 14,000L tank was

  12. Am-241 as a metabolic tracer for inhaled Pu nitrate in external chest counting

    International Nuclear Information System (INIS)

    Ishigure, Nobuhito; Nakano, Takashi; Enomoto, Hiroko

    2000-01-01

    The most difficult radionuclides to measure by extemal chest counting are the isotopes of plutonium (Pu). They are detected through weak emission of low energy L X-rays. The Pu treated in nuclear fuel cycle is usually accompanied with 241 Am produced from 241 Pu by β disintegration, which emits γ-rays of 60 keV with the emission rate of 0.36, being more penetrable than the L X-rays. The 241 Am could improve the detection limit of chest counting of Pu, if it being used as a metabolic tracer for Pu in lungs. It has already been shown that the 241 Am which would probably be embedded in a matrix of PuO 2 is cleared from the lungs at the same rate as the Pu for long time after intake (N. Ishigure, et al., Radiat, Prot. Dosim., 79, 133, 1998), which supports the validity of 241 Am as a tracer of inhaled Pu in external chest counting. In the present work another possible chemical form present in work places, Pu nitrate, has been investigated. The solution of Pu(NO 3 ) 4 was nebulized using a compressed-air operated nebulizer. The resultant droplets were passed through a tube with fresh air and conduced into a multi-port nose-only exposure chamber, which resulted in polydisperse aerosols of Pu(NO 3 ) 4 with 0.6 μm in AMAD. Young adult male Wistar rats, being 13 weeks old and weighing 230 g at the time of exposure were used. The exposed rats were periodically sacrificed and the radioactivity of 241 Am and 238/239/240 Pu in the autopsied lungs were measured by photon spectrometry with a NaI/CsI phoswich detector system. The activity ratio of 241 Am vs. Pu in lungs, 2.4% at the exposure, slowly decreased to 2.1% at 4 week and 2.0% at 24 weeks. However, from practical point of view, it could be concluded that 241 Am would be a valid metabolic tracer for inhaled Pu nitrate at least for half a year post inhalation, considering the detection limit for Pu in chest counting, which is much greater than the ALI of Pu and the large uncertainties due to the estimation of chest wall

  13. Pu-Th separation studies employing di(2-ethylhexyl)isobutyramide (D2EHIBA) as extractant from nitric acid medium

    International Nuclear Information System (INIS)

    Pathak, P.N.; Prabhu, D.R.; Rizvi, G.H.; Ruikar, P.B.; Kumbhare, L.B.; Mohapatra, P.K.; Manchanda, V.K.

    2003-01-01

    An attempt has been made to explore the use of di(2-ethylhexyl)isobutyramide (D2EHIBA) as an extractant for the recovery of Pu from the (proposed) AHWR fuel fabrication scrap solution. The extraction of Pu in the hexavalent state has been found to be distinctly more efficient than that in the tetravalent state. Distribution studies have been carried out by maintaining Pu as Pu(VI) employing AgO as the oxidant. Scrubbing at 5 M HNO 3 has been proposed to reduce the interference due to the co-extracted Th(IV). Quantitative stripping of the extracted Pu was achieved using hydroxyl ammonium-nitrate (HAN) as reductant. Ion exchange studies have been carried out for the final purification of Pu. It is proposed to employ the cation exchanger, Biorad AG 50X8 for the final purification of Pu from the stripped solution, keeping Pu as Pu(III). (orig.)

  14. The determination of Pu-241 by liquid scintillation counting in liquid effluents of the Karlsruhe Nuclear Research Center

    International Nuclear Information System (INIS)

    Godoy, J.M.; Schuettelkopf, H.; Pimpl, M.

    1983-04-01

    A procedure was developed to measure Pu-241 by liquid scintillation counting. Sample preparation was performed by electroplating of plutonium on stainless steel planchets. To correct the selfabsorption, the linear dependence of counting efficiency in the liquid scintillation counter from the resolution in the alpha spectrometer was used. Pu-238, Pu-239+240 and Pu-241 were measured in the liquid effluents of the Karlsruhe Nuclear Research Center (KfK). The concentrations in monthly mixed samples ranged from 0.07 until 46 nCi Pu-238/m 3 , from 0.13 until 2.1 nCi Pu-239+240/m 3 and from 25 until 190 nCi Pu-241/m 3 . Between 5.4% and 41% of the plutonium content of the KfK waste water are released to the River Old Rhine. The values for the activity ratio Pu-238/Pu-239+240 are between 0.39 and 1.1 and for Pu-241/Pu-239+240 are between 11 and 300. The mean value for Pu-241/Pu-239+240 is 61. The dose exposure of the environmental population of the Karlsruhe Nuclear Research Center caused by released Pu-241 is negligible low. (orig./HP) [de

  15. Plutonium(IV) peroxide formation in nitric medium and kinetics Pu(VI) reduction by hydrogen peroxide

    International Nuclear Information System (INIS)

    Maillard, C.; Adnet, J.M.

    2001-01-01

    Reduction of plutonium (VI) to Pu(IV) with hydrogen peroxide is a step in industrial processes used to purify plutonium nitrate solutions. This operation must be carefully controlled, in order to avoid any formation of the Pu(IV) peroxide green precipitate and to obtain exclusively Pu(IV). This led us to study the acidity and Pu and H 2 O 2 concentrations influences on the precipitate appearance and to perform a Pu(VI) reduction kinetic study on a wide range of acidities ([HNO 3 ]: 0.5 to 8 M), plutonium concentrations ([Pu(VI)]: 0.1 to 0.8 M) and [H 2 O 2 ]/[Pu(VI)] ratio (from 1 to 8). Thus, the domain of Pu(IV) peroxide formation and the reactional paths were established. With the exception of 0.5 M nitric acid medium, the kinetic curves show two distinct regims: the first one corresponds to an induction period where the Pu(VI) concentration doesn't change, the second corresponds to a linear decrease of Pu(VI). An increase of the temperature greatly accelerates the Pu(VI) reduction rate while [H 2 O 2 ]/[Pu(VI)] has almost no influence. The Pu(VI) total reduction time decreases when initial concentration of plutonium increases. By increasing nitric acid concentration from 0.5 M to 6 M, the total Pu(VI) reduction time decreases. This time increases when [HNO 3 ] varies from 6 M to 8 M. (orig.)

  16. Complicaciones en las puérperas laparotomizadas de urgencia

    Directory of Open Access Journals (Sweden)

    Victor Manuel Sierra Alfonso

    2014-11-01

    Full Text Available La presencia de una complicación intrabdominal postoperatoria después de una laparotomía agrava el estado de salud del paciente y ensombrece el pronóstico, a pesar del uso adecuado de antimicrobianos, de la correcta nutrición y de las ventajas de los cuidados intensivos. Se realizó un estudio retrospectivo descriptivo, con el objetivo de caracterizar las complicaciones en las puérperas, a las que se les practicaron laparotomías de urgencia. Se analizaron las referidas pacientes atendidas en el Hospital Ginecoobstétrico “Piti Fajardo” y en el Hospital General Docente “Aleida Fernández Chardiet”, en el periodo comprendido entre enero del 2010 y diciembre del 2012. La muestra quedó conformada por nueve pacientes. Las complicaciones más presentadas fueron los trastornos hidroelectrolíticos y los trastornos del equilibrio ácido básico. No hubo muerte materna ni fetal. Las puérperas que más complicaciones presentaron fueron las de 35 años y más, con diagnóstico de placenta acreta, hematoma de la cúpula vaginal y atonía uterina. El tiempo de evolución hasta el tratamiento definitivo fue menor de 12 horas

  17. Electrodeposition of uranium and transuranic metals (Pu) on solid cathode

    International Nuclear Information System (INIS)

    Laplace, A. F.; Lacquement, J.; Willitt, J. L.; Finch, R. A.; Fletcher, G. A.; Williamson, M. A.

    2008-01-01

    The results from a study of U and Pu metal electrodeposition from molten eutectic LiCl-KCl on a solid inert cathode are presented. This study has been conducted using ∼ to 50 g of U-Pu together with rare earths (mostly Nd) and 1.5 kg of salt. The introduction of a three-electrode probe with an Ag/AgCl reference electrode has allowed voltammetric measurement during electrolysis and control of the cathode potential versus the reference. Cyclic and square-wave voltammetric measurements proved to be very useful tools for monitoring the electrolysis as well as selecting the cathode versus reference potential to maximize the separation between actinides and rare earths. The voltammetric data also highlighted the occurrence of back reactions between the cathode deposit and oxidizing equivalents formed at the anode that remained in the molten salt electrolyte. Any further electrolysis test needs to be conducted continuously and followed by immediate removal of the cathode to minimize those back reactions. (authors)

  18. Neutron spectra of /sup 239/Pu-Be neutron sources

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, A; Nagarajan, P S [Bhabha Atomic Research Centre, Bombay (India). Div. of Radiation Protection

    1977-01-01

    Neutron spectra of /sup 239/Pu-Be(..cap alpha..,n) sources have been calculated by using the most recent data on the differential cross sections and angular distributions. The contribution from the multibody break-up reaction /sup 9/Be(..cap alpha..,..cap alpha..n)/sup 8/Be has also been incorporated. Modifications to the primary spectrum due to the secondary interactions in the source such as elastic scattering with beryllium, oxygen and plutonium and the /sup 9/Be(n,2n) and /sup 239/Pu(n,f) reaction have been calculated for different strengths and geometries. The present calculation has shown that the spectrum changes considerably because of these events within the source by way of smearing of peaks and filling up of valleys and raising the low energy part of the spectrum. Increase in H/D value leads to channeling of extra neutrons into the equatorial plane at the cost of the neutrons along the axial direction. The present calculations show that inclusion of secondary interactions to the extent considered in this work does not account completely for the increased intensity in the lower energy end of the measured spectrum.

  19. Low-level 239PuO2 lifespan studies

    International Nuclear Information System (INIS)

    Sanders, C.L.

    1985-01-01

    This project will produce data to generate a dose-response curve (and to evaluate other statistical methods that also incorporate survival time) for lung-tumor incidence in Wistar rats following inhalation of 239 PuO 2 at levels producing lifetime radiation doses to the lung of 2000 rad. The lung clearance of 239 Pu is best represented by a two-exponential equation, with 78% of the initial alveolar depositions (IAD) cleared with a half-time of 19 days and 22% cleared with a half-time of 180 days. A total of 593 of 2134 exposed and 242 of 1058 sham-exposed rats have died. Among the dead rats, the percent with primary lung tumors was 71% for the 150-nCi group, 70% for the 82-nCi group, and 23% for the 32-nCi group. No lung tumors have been found in controls, and only three have been found at an IAD of < 7.5 nCi. 1 figure, 3 tables

  20. Characterization of a neutron source of 239PuBe

    International Nuclear Information System (INIS)

    Hernandez V, R.; Chacon R, A.; Hernandez D, V. M.; Mercado, G. A.; Vega C, H. R.; Ramirez G, J.

    2009-10-01

    The spectrum equivalent dose and environmental equivalent dose f a 239 PuBe source have been determined. The appropriate handling of a neutron source depends on the knowledge of its characteristics, such as its energy distribution, total rate of flowing and dosimetric magnitudes. In many facilities have not spectrometer that allows to determine the spectrum and then area monitors are used that give a dosimetric magnitude starting from measuring the flowing rate and the use of conversion factors, however this procedure has many limitations and it is preferable to measure the spectra and starting from this information the interest dosimetric magnitudes are calculated. In this work a Bonner sphere spectrometer has been used with a 6 LiI(Eu) scintillator obtaining the count rates that produce, to a distance of 100 cm, a 239 PuBe source of 1.85E(11) Bq. The spectrum was reconstructed starting from the count rates using BUNKIUT code and response matrix UTA4. With the spectrum information was calculated the source intensity, total flow, energy average, equivalent dose rate, environmental equivalent dose rate, equivalent dose coefficient and environmental equivalent dose coefficient. By means of two area monitors for neutrons, Eberline ASP-1 and LB 6411 of Berthold the equivalent dose and environmental equivalent dose were measured. The determinate values were compared with those reported in literature and it found that are coincident inside 17%. (Author)

  1. The absorption spectra of Pu(VI), -(V) and -(IV) produced electrochemically in carbonate-bicarbonate media

    International Nuclear Information System (INIS)

    Wester, D.W.; Sullivan, J.C.

    1983-01-01

    Absorption spectra in carbonate and bicarbonate media have been measured for various oxidation states of plutonium. The oxidation state of plutonium was adjusted electrochemically (Pu(VI)-V), Esub(f)=+0.11 V vs. SCE) to avoid contamination by redox reagents. In carbonate medium the spectra of Pu(VI) and Pu(V) showed marked differences from the spectra of the same oxidation state in acidic solutions. In bicarbonate the spectra of Pu(VI) and Pu(IV) also differed from the corresponding spectra in acidic media. Reduction to Pu(III) resulted in a precipitate in both carbonate and bicarbonate media. (author)

  2. Chronology of Pu isotopes and 236U in an Arctic ice core.

    Science.gov (United States)

    Wendel, C C; Oughton, D H; Lind, O C; Skipperud, L; Fifield, L K; Isaksson, E; Tims, S G; Salbu, B

    2013-09-01

    In the present work, state of the art isotopic fingerprinting techniques are applied to an Arctic ice core in order to quantify deposition of U and Pu, and to identify possible tropospheric transport of debris from former Soviet Union test sites Semipalatinsk (Central Asia) and Novaya Zemlya (Arctic Ocean). An ice core chronology of (236)U, (239)Pu, and (240)Pu concentrations, and atom ratios, measured by accelerator mass spectrometry in a 28.6m deep ice core from the Austfonna glacier at Nordaustlandet, Svalbard is presented. The ice core chronology corresponds to the period 1949 to 1999. The main sources of Pu and (236)U contamination in the Arctic were the atmospheric nuclear detonations in the period 1945 to 1980, as global fallout, and tropospheric fallout from the former Soviet Union test sites Novaya Zemlya and Semipalatinsk. Activity concentrations of (239+240)Pu ranged from 0.008 to 0.254 mBq cm(-2) and (236)U from 0.0039 to 0.053 μBq cm(-2). Concentrations varied in concordance with (137)Cs concentrations in the same ice core. In contrast to previous published results, the concentrations of Pu and (236)U were found to be higher at depths corresponding to the pre-moratorium period (1949 to 1959) than to the post-moratorium period (1961 and 1962). The (240)Pu/(239)Pu ratio ranged from 0.15 to 0.19, and (236)U/(239)Pu ranged from 0.18 to 1.4. The Pu atom ratios ranged within the limits of global fallout in the most intensive period of nuclear atmospheric testing (1952 to 1962). To the best knowledge of the authors the present work is the first publication on biogeochemical cycles with respect to (236)U concentrations and (236)U/(239)Pu atom ratios in the Arctic and in ice cores. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Dose-response study in F344 rats exposed to (U,Pu)O2 or PuO2

    International Nuclear Information System (INIS)

    Mewhinney, J.A.; Eidson, A.F.; Hahn, F.F.; Scott, B.R.; Seiler, F.A.; Boecker, B.B.

    1987-01-01

    The relationship of radiation dose to lung and the biological effect observed was investigated following inhalation of two types of plutonium-containing particulate materials in rats. Bulk powder samples of the two materials were obtained from within gloveboxes used in the routine manufacture of mixed plutonium and uranium oxide nuclear fuel. The materials were a solid solution of uranium and plutonium treated at 1750 0 C and a PuO 2 feedstock. Groups of rats received a single inhalation exposure to a material to achieve one of three levels of initial pulmonary burden. Rats were maintained for their lifespan to observe the biological effects produced. These effects were observed in the lungs of rats exposed to either type of particle. The same types of lung cancer were produced by both particulate materials. The incidences of cancers were also similar at comparable levels of initial pulmonary burden for the two materials. The crude incidence of lung cancers for rats exposed to these materials was not different than those reported for similar studies that used laboratory-produced aerosols of PuO 2 . Using a linear dose-effect model, the relative risk of lung cancer for rats exposed to these industrial materials was 2.3 +- 1.0 (SE) at a lung dose of 100 rad. The doubling dose for lung cancers was 78 +- 63 rad to lung to median life span. 21 refs., 9 figs., 10 tabs

  4. Study of new U(VI) and Pu(VI) coprecipitation methods for the preparation of (U,Pu)O2

    International Nuclear Information System (INIS)

    Sanoit, J. de.

    1990-01-01

    Two U(VI) and Pu(VI) coprecipitation methods have been studied, for the definition of new processes to prepare (U,Pu)O 2 mixed oxides suitable for making MoX fuels or fast breeder reactor fuels. The first system is based on the coprecipitation of a new U(VI), Pu(VI) compound; ammonium uranoplutonate, where as a second system is related to the precipitation of uranyl plutonyl monocarbonate. Experimental conditions to optimize the precipitation and the filtration steps of these two systems have been determined. After calcination under reducing conditions, the mixed oxides obtained are characterized according to different techniques: granulometry, thermogravimetry, solubility in boiling HNO 3 solutions. The properties of such oxides are excellent. The possible processes for preparing (U, Pu)O 2 using these new routes are compared with those actually exploited [fr

  5. The application of data derived from autoradiographic studies with 241Pu in the formulation of a bone dosimetric model for 239Pu

    International Nuclear Information System (INIS)

    Priest, N.D.; Hunt, B.W.

    1979-01-01

    Recently a dosimetric model for 239 Pu in bone has been published which in conjunction with the general ICRP dosimetric model for actinides is used to calculate annual limits of intake for 239 Pu. This model allows for the burial of plutonium in bone, for the recycling of plutonium within the skeleton and for the retention of plutonium in the bone marrow. The model was based upon published descriptions of the distribution and redistribution patterns of plutonium in bone and on evidence obtained from autoradiographic studies of bone from animals injected with 241 Pu. The experiments with 241 Pu demonstrated the initial uptake of plutonium by bone surfaces. As a result of the growth and drift processes much of this plutonium became either buried in the bone or was retained within macrophages in the bone marrow. (author)

  6. DFT and two-dimensional correlation analysis methods for evaluating the Pu3+–Pu4+ electronic transition of plutonium-doped zircon

    International Nuclear Information System (INIS)

    Bian, Liang; Dong, Fa-qin; Song, Mian-xin; Dong, Hai-liang; Li, Wei-Min; Duan, Tao; Xu, Jin-bao; Zhang, Xiao-yan

    2015-01-01

    Highlights: • Effect of Pu f-shell electron on the electronic property of zircon is calculated via DFT and 2D-CA techniques. • Reasons of Pu f-shell electron influencing on electronic properties are systematically discussed. • Phase transitions are found at two point 2.8 mol% and 7.5 mol%. - Abstract: Understanding how plutonium (Pu) doping affects the crystalline zircon structure is very important for risk management. However, so far, there have been only a very limited number of reports of the quantitative simulation of the effects of the Pu charge and concentration on the phase transition. In this study, we used density functional theory (DFT), virtual crystal approximation (VCA), and two-dimensional correlation analysis (2D-CA) techniques to calculate the origins of the structural and electronic transitions of Zr 1−c Pu c SiO 4 over a wide range of Pu doping concentrations (c = 0–10 mol%). The calculations indicated that the low-angular-momentum Pu-f xy -shell electron excites an inner-shell O-2s 2 orbital to create an oxygen defect (V O-s ) below c = 2.8 mol%. This oxygen defect then captures a low-angular-momentum Zr-5p 6 5s 2 electron to form an sp hybrid orbital, which exhibits a stable phase structure. When c > 2.8 mol%, each accumulated V O-p defect captures a high-angular-momentum Zr-4d z electron and two Si-p z electrons to create delocalized Si 4+ → Si 2+ charge disproportionation. Therefore, we suggest that the optimal amount of Pu cannot exceed 7.5 mol% because of the formation of a mixture of ZrO 8 polyhedral and SiO 4 tetrahedral phases with the orientation (10-1). This study offers new perspective on the development of highly stable zircon-based solid solution materials

  7. ZPR-6 assembly 7 high {sup 240}Pu core experiments : a fast reactor core with mixed (Pu,U)-oxide fuel and a centeral high{sup 240}Pu zone.

    Energy Technology Data Exchange (ETDEWEB)

    Lell, R. M.; Morman, J. A.; Schaefer, R.W.; McKnight, R.D.; Nuclear Engineering Division

    2009-02-23

    ZPR-6 Assembly 7 (ZPR-6/7) encompasses a series of experiments performed at the ZPR-6 facility at Argonne National Laboratory in 1970 and 1971 as part of the Demonstration Reactor Benchmark Program (Reference 1). Assembly 7 simulated a large sodium-cooled LMFBR with mixed oxide fuel, depleted uranium radial and axial blankets, and a core H/D near unity. ZPR-6/7 was designed to test fast reactor physics data and methods, so configurations in the Assembly 7 program were as simple as possible in terms of geometry and composition. ZPR-6/7 had a very uniform core assembled from small plates of depleted uranium, sodium, iron oxide, U{sub 3}O{sub 8} and Pu-U-Mo alloy loaded into stainless steel drawers. The steel drawers were placed in square stainless steel tubes in the two halves of a split table machine. ZPR-6/7 had a simple, symmetric core unit cell whose neutronic characteristics were dominated by plutonium and {sup 238}U. The core was surrounded by thick radial and axial regions of depleted uranium to simulate radial and axial blankets and to isolate the core from the surrounding room. The ZPR-6/7 program encompassed 139 separate core loadings which include the initial approach to critical and all subsequent core loading changes required to perform specific experiments and measurements. In this context a loading refers to a particular configuration of fueled drawers, radial blanket drawers and experimental equipment (if present) in the matrix of steel tubes. Two principal core configurations were established. The uniform core (Loadings 1-84) had a relatively uniform core composition. The high {sup 240}Pu core (Loadings 85-139) was a variant on the uniform core. The plutonium in the Pu-U-Mo fuel plates in the uniform core contains 11% {sup 240}Pu. In the high {sup 240}Pu core, all Pu-U-Mo plates in the inner core region (central 61 matrix locations per half of the split table machine) were replaced by Pu-U-Mo plates containing 27% {sup 240}Pu in the plutonium

  8. R-matrix analyses of the 235U and 239Pu neutron cross sections

    International Nuclear Information System (INIS)

    Derrien, H.; de Saussure, G.; Larson, N.M.; Leal, L.C.; Perez, R.B.

    1988-01-01

    The resonance parameter analysis code SAMMY was used to perform consistent resonance analyses of several 235 U and 239 Pu fission and capture cross section and transmission measurements up to 110 eV for 235 U and up to 1 keV for 239 Pu. The method of analysis, the measurement selection and the results are briefly outlined in this paper

  9. High-240Pu fuel worth in the Fast Test Reactor Engineering Mockup

    International Nuclear Information System (INIS)

    Daughtry, J.W.; Dobbin, K.D.

    1975-01-01

    Reactivity effects associated with the replacement of low- 240 Pu fuel with high- 240 Pu fuel were calculated and compared to measurements made in the FTR Engineering Mockup Critical (EMC). When the Pu and U isotopic compositions were changed in a way that increased the amounts of 240 Pu and 241 Pu and reduced the amounts of 239 Pu and 238 U while conserving total fissile mass and total fertile mass, the reactivity effect was positive. Calculation-to-experiment bias factors were obtained for this type of change and for the replacement of Fe 2 O 3 with U 3 O 8 in subassembly-size zones of the EMC. The k/sub e/--k/sub c/ bias decreased when high- 240 Pu fuel was introduced and increased when Fe 2 O 3 was replaced with U 3 O 8 . When the two changes were combined, their effects on the k/sub e/ --k/sub c/ bias tended to cancel out. The work described is related to plans for the utilization of light water reactor discharge Pu in the FTR

  10. Chemical approaches to understanding the environmental behavior of Pu, Np, and Tc

    International Nuclear Information System (INIS)

    Bondietti, E.A.

    1978-01-01

    Some topics discussed are as follows: speciation behavior of Pu, Np, and Tc; thermodynamic and radiochemical behavior; sorption studies with soils; Pu oxidation states in fresh water; Np oxidation states in soils; effect of oxidation state of Tc on environmental transport predictions; and thermodynamic calculations of Tc speciation

  11. Transuranium perrhenates: Np(IV), Pu(IV) and (III), Am (III)

    International Nuclear Information System (INIS)

    Silvestre, Jean-Paul; Freundlich, William; Pages, Monique

    1977-01-01

    Synthesis in aqueous solution and by solid state reactions, crystallographical characterization and study of the stability of some transuranium perrhenates: Asup(n+)(ReO 4 - )sub(n) (A=Np(IV), Pu(IV), Pu(III), Am(III) [fr

  12. {sup 241}Pu concentrations in water, plankton and fish from the southern Baltic Sea

    Energy Technology Data Exchange (ETDEWEB)

    Struminska-Parulska, D.I.; Skwarzec, B. [Gdansk, Univ. (Poland). Facuty of Chemistry

    2013-08-01

    The aim of the work was to determine {sup 241}Pu activities in different components (water, plankton and fish) of the southern Baltic Sea ecosystem. Measurement of {sup 241}Pu in the samples was done indirectly by determining the increment in {sup 241}Am from the decay of the {beta}-emitting {sup 241}Pu in samples collected 10-15 years after the Chernobyl accident. Enhanced levels of {sup 241}Pu were observed in all analyzed Baltic samples. The highest {sup 241}Pu concentrations in fish were found in Perciformes: benthic round goby (0.863 {+-} 0.066 mBq/g ww) and pelagic perch (0.666 {+-} 0.001 mBq/g ww). Plutonium is also non-uniformly distributed in the organs and tissues of the analyzed fish; especially pelagic herring and cod as well as benthic flounder. Most of {sup 241}Pu in flounder, herring and cod is located in soft tissues, especially digestive organs (stomach, intestine, liver). The annual individual effective doses calculated on the basis of {sup 241}Pu concentrations in fish indicated that the impact of the consumption of {sup 241}Pu containing Baltic fish on the annual effective dose for a statistical inhabitant of Poland was very small. (orig.)

  13. PU.1 cooperates with IRF4 and IRF8 to suppress pre-B cell leukemia

    Science.gov (United States)

    Pang, Swee Heng Milon; Minnich, Martina; Gangatirkar, Pradnya; Zheng, Zhiqiang; Ebert, Anja; Song, Guangchun; Dickins, Ross A; Corcoran, Lynn M; Mullighan, Charles G.; Busslinger, Meinrad; Huntington, Nicholas D; Nutt, Stephen L; Carotta, Sebastian

    2016-01-01

    The Ets family transcription factor PU.1 and the interferon regulatory factor (IRF)4 and IRF8 regulate gene expression by binding to composite DNA sequences known as Ets/interferon consensus elements (EICE). Although all three factors are expressed from the onset of B cell development, single deficiency of these factors in B cell progenitors only mildly impacts on bone marrow B-lymphopoiesis. Here we tested whether PU.1 cooperates with IRF factors in regulating early B cell development. Lack of PU.1 and IRF4 resulted in a partial block in development the pre-B cell stage. The combined deletion of PU.1 and IRF8 reduced recirculating B cell numbers. Strikingly, all PU.1/IRF4 and approximately 50% of PU.1/IRF8 double deficient mice developed pre-B cell acute lymphoblastic leukemia (B-ALL) associated with reduced expression of the established B-lineage tumor suppressor genes, Ikaros and Spi-B. These genes are directly regulated by PU.1/IRF4/IRF8, and restoration of Ikaros or Spi-B expression inhibited leukemic cell growth. In summary, we demonstrate that PU.1, IRF4 and IRF8 cooperate to regulate early B cell development and to prevent pre-B-ALL formation. PMID:26932576

  14. Observations of surface-mediated reduction of Pu(VI) to Pu(IV) on hematite nanoparticles by ATR FT-IR

    Energy Technology Data Exchange (ETDEWEB)

    Emerson, Hilary P. [Florida International Univ., Applied Research Center, Miami, FL (United States); Powell, Brian A. [Clemson Univ., Dept. of Enviromental Engineering and Earth Sciences, Anderson, SC (United States)

    2015-07-01

    Previous studies have shown that mineral surfaces may facilitate the reduction of plutonium though the mechanisms of the reduction are still unknown. The objective of this study is to use batch sorption and attenuated total reflectance Fourier transform infrared spectroscopy experiments to observe the surface-mediated reduction of plutonium on hematite nanoparticles. These techniques allow for in situ measurement of reduction of plutonium with time and may lead to a better understanding of the mechanisms of surface mediated reduction of plutonium. For the first time, ATR FT-IR peaks for Pu(VI) sorbed to hematite are measured at ∝ 916 cm{sup -1}, respectively. The decrease in peak intensity with time provides a real-time, direct measurement of Pu(VI) reduction on the hematite surface. In this work pseudo first order rate constants estimated at the high loadings (22 mg{sub Pu}/g{sub hematite}, 1.34 x 10{sup -6} M{sub Pu}/m{sup 2}) for ATR FT-IR are approximately 10 x slower than at trace concentrations based on previous work. It is proposed that the reduced rate constant at higher Pu loadings occurs after the reduction capacity due to trace Fe(II) has been exhausted and is dependent on the oxidation of water and possibly electron shuttling based on the semiconducting nature of hematite. Therefore, the reduction rate at higher loadings is possibly due to the thermodynamic favorability of Pu(IV)-hydroxide complexes.

  15. The production of {sup 238-242}Pu(n,γ){sup 239-243}Pu fissionable fluids in a fusion-fission hybrid reactor

    Energy Technology Data Exchange (ETDEWEB)

    Guenay, Mehtap [Inoenue Univ., Malatya (Turkey). Physics Dept.

    2014-03-15

    In this study, the effect of spent fuel grade plutonium content on {sup 239-243}Pu was investigated in a designed hybrid reactor system. In this system, the fluids were composed of a molten salt, heavy metal mixture with increased mole fractions 99-95 % Li{sub 20}Sn{sub 80}-1-5 % SFG-Pu, 99-95 % Li{sub 20}Sn{sub 80}-1-5 % SFG-PuF{sub 4}, 99-95 % Li{sub 20}Sn{sub 80}-1-5 % SFG-PuO{sub 2}. Beryllium (Be) is a neutron multiplier by (n,2n) reactions. Thence, a Be zone of 3 cm thickness was used in order to contribute to fissile fuel breeding between the liquid first wall and a 9Cr2WVTa ferritic steel blanket which is used as structural material. The production of {sup 238-242}Pu(n,γ){sup 239-243}Pu was calculated in liquid first wall, blanket and shielding zones. Three-dimensional nucleonic calculations were performed by using the most recent version MCNPX-2.7.0 Monte Carlo code and nuclear data library ENDF/B-VII.0. (orig.)

  16. Structural studies of the phase separation in the UO2–PuO2–Pu2O3 ternary system

    International Nuclear Information System (INIS)

    Truphémus, Thibaut; Belin, Renaud C.; Richaud, Jean-Christophe; Reynaud, Muriel; Martinez, Marie-Annick; Félines, Isabelle; Arredondo, Antoine; Miard, Audrey; Dubois, Thierry; Adenot, Frédéric; Rogez, Jacques

    2013-01-01

    In the oxygen hypo-stoichiometric range of (U 1−y Pu y )O 2−x mixed oxide MOX fuels, the U–Pu–O phase diagram is known to exhibit a large biphasic domain depending on the Pu content. However, the phase equilibria are still to be fully described as various representations are proposed in the literature. In the present work, we notify new insights into the phase separation occurring in the UO 2 –PuO 2 –Pu 2 O 3 domain at room temperature. Our microstructural and X-ray diffraction results are compared to the different representations reported in the literature. We provide, for the first time in the hypo-stoichiometric domain, an indisputable experimental observation of a triphasic region at high Pu content, composed of two fluorite-type structures and of one α-Pu 2 O 3 sesquioxyde type structure. These results are in contradiction with previous experimental representations of the U–Pu–O ternary system.

  17. Chronology of Pu isotopes and {sup 236}U in an Arctic ice core

    Energy Technology Data Exchange (ETDEWEB)

    Wendel, C.C., E-mail: cato.wendel@umb.no [Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas (Norway); Oughton, D.H., E-mail: deborah.oughton@umb.no [Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas (Norway); Lind, O.C., E-mail: ole-christian.lind@umb.no [Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas (Norway); Skipperud, L., E-mail: lindis.skipperud@umb.no [Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas (Norway); Fifield, L.K., E-mail: keith.fifield@anu.edu.au [Department of Nuclear Physics, Australian National University, Canberra ACT 0200 (Australia); Isaksson, E., E-mail: elisabeth.isaksson@npolar.no [Norwegian Polar Institute, Fram Centre, Hjalmar Johansens Gate 14, N9296 Tromsø (Norway); Tims, S.G., E-mail: steve.tims@anu.edu.au [Department of Nuclear Physics, Australian National University, Canberra ACT 0200 (Australia); Salbu, B., E-mail: brit.salbu@umb.no [Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas (Norway)

    2013-09-01

    In the present work, state of the art isotopic fingerprinting techniques are applied to an Arctic ice core in order to quantify deposition of U and Pu, and to identify possible tropospheric transport of debris from former Soviet Union test sites Semipalatinsk (Central Asia) and Novaya Zemlya (Arctic Ocean). An ice core chronology of {sup 236}U, {sup 239}Pu, and {sup 240}Pu concentrations, and atom ratios, measured by accelerator mass spectrometry in a 28.6 m deep ice core from the Austfonna glacier at Nordaustlandet, Svalbard is presented. The ice core chronology corresponds to the period 1949 to 1999. The main sources of Pu and {sup 236}U contamination in the Arctic were the atmospheric nuclear detonations in the period 1945 to 1980, as global fallout, and tropospheric fallout from the former Soviet Union test sites Novaya Zemlya and Semipalatinsk. Activity concentrations of {sup 239+240}Pu ranged from 0.008 to 0.254 mBq cm{sup −2} and {sup 236}U from 0.0039 to 0.053 μBq cm{sup −2}. Concentrations varied in concordance with {sup 137}Cs concentrations in the same ice core. In contrast to previous published results, the concentrations of Pu and {sup 236}U were found to be higher at depths corresponding to the pre-moratorium period (1949 to 1959) than to the post-moratorium period (1961 and 1962). The {sup 240}Pu/{sup 239}Pu ratio ranged from 0.15 to 0.19, and {sup 236}U/{sup 239}Pu ranged from 0.18 to 1.4. The Pu atom ratios ranged within the limits of global fallout in the most intensive period of nuclear atmospheric testing (1952 to 1962). To the best knowledge of the authors the present work is the first publication on biogeochemical cycles with respect to {sup 236}U concentrations and {sup 236}U/{sup 239}Pu atom ratios in the Arctic and in ice cores. - Highlights: • Concentrations and atom ratios of Pu and {sup 236}U determined in an Arctic ice core. • Concentrations of U and Pu found to be higher pre- than post-moratorium. • U and Pu concentrations

  18. Assembly-level analysis of heterogeneous Th–Pu PWR fuel

    International Nuclear Information System (INIS)

    Zainuddin, Nurjuanis Zara; Parks, Geoffrey T.; Shwageraus, Eugene

    2017-01-01

    Highlights: • We directly compare homogeneous and heterogeneous Th–Pu fuel. • Examine whether there is an increase in Pu incineration in the latter. • Homogeneous fuel was able to achieve much higher Pu incineration. • In the heterogeneous case, U-233 breeding is faster (larger power fraction), thus decreasing incineration of Pu. - Abstract: This study compares homogeneous and heterogeneous thorium–plutonium (Th–Pu) fuel assemblies (with high Pu content – 20 wt%), and examines whether there is an increase in Pu incineration in the latter. A seed-blanket configuration based on the Radkowsky thorium reactor concept is used for the heterogeneous assembly. This separates the thorium blanket from the uranium seed, or in this case a plutonium seed. The seed supplies neutrons to the subcritical thorium blanket which encourages the in situ breeding and burning of "2"3"3U, allowing the fuel to stay critical for longer, extending burnup of the fuel. While past work on Th–Pu seed-blanket units shows superior Pu incineration compared to conventional U–Pu mixed oxide fuel, there is no literature to date that directly compares the performance of homogeneous and heterogeneous Th–Pu assembly configurations. Use of exactly the same fuel loading for both configurations allows the effects of spatial separation to be fully understood. It was found that the homogeneous fuel with and without burnable poisons was able to achieve much higher Pu incinerations than the heterogeneous fuel configurations, while still attaining a reasonably high discharge burnup. This is because in the heterogeneous cases, "2"3"3U breeding is faster, thereby contributing to a much larger fraction of total power produced by the assembly. In contrast, "2"3"3U build-up is slower in the homogeneous case and therefore Pu burning is greater. This "2"3"3U begins to contribute a significant fraction of power produced only towards the end of life, thus extending criticality, allowing more Pu to

  19. Inhaled 239PuO2 in rats with pulmonary emphysema. II

    International Nuclear Information System (INIS)

    Lundgren, D.L.; Mauderly, J.L.; Carlton, W.W.; Hahn, F.F.

    1988-01-01

    The modifying effects of pre-existing pulmonary emphysema on deposition, distribution, retention, and effects of inhaled 239 PuO 2 in the rat were investigated. The presence of emphysema in the rats tested was indicated by respiratory function measurements and confirmed microscopically. Initial lung burdens of 239 Pu per kg body weight were less in rats with emphysema than in control rats; however, the retention of 239 Pu was similar in emphysematous and control rats. Survival and lung tumor occurrence were similar in emphysematous and control rats exposed to 239 PuO 2 . We concluded that rats with pre-existing pulmonary emphysema were not more sensitive to the effects of inhaled 239 PuO 2 than control rats. (author)

  20. Vertical distribution of (241)Pu in the southern Baltic Sea sediments.

    Science.gov (United States)

    Strumińska-Parulska, Dagmara I

    2014-12-15

    The vertical distribution of plutonium (241)Pu in marine sediments can assist in determining the deposition history and sedimentation process of analyzed regions. In addition, (241)Pu/(239+240)Pu activity ratio could be used as a sensitive fingerprint for radioactive source identification. The present preliminary studies on vertical distribution of (241)Pu in sediments from four regions of the southern Baltic Sea are presented. The distribution of (241)Pu was not uniform and depended on sediment geomorphology and depth as well as location. The highest concentrations of plutonium were found in the surface layers of all analyzed sediments and originated from the Chernobyl accident. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Sorption of Pu(IV) from nitric acid by bifunctional anion-exchange resins

    International Nuclear Information System (INIS)

    Bartsch, R.A.; Zhang, Z.Y.; Elshani, S.; Zhao, W.; Jarvinen, G.D.; Barr, M.E.; Marsh, S.F.; Chamberlin, R.M.

    1999-01-01

    Anion exchange is attractive for separating plutonium because the Pu(IV) nitrate complex is very strongly sorbed and few other metal ions form competing anionic nitrate complexes. The major disadvantage of this process has been the unusually slow rate at which the Pu(IV) nitrate complex is sorbed by the resin. The paper summarizes the concept of bifunctional anion-exchange resins, proposed mechanism for Pu(IV) sorption, synthesis of the alkylating agent, calculation of K d values from Pu(IV) sorption results, and conclusions from the study of Pu(IV) sorption from 7M nitric acid by macroporous anion-exchange resins including level of crosslinking, level of alkylation, length of spacer, and bifunctional vs. monofunctional anion-exchange resins

  2. Current technics and management strategy for Pu-contaminated wastes at PNC

    International Nuclear Information System (INIS)

    1981-02-01

    Power Reactor and Nuclear Fuel Development Corporation (PNC) was designated as a leading organization for the Pu-contaminated waste technology program in Japan. For this purpose, number of efforts in the research and development are proceeding. That is, Pu-contaminated waste technology including volume reduction system and the immobilization of wastes is being developed. The design of a Pu-contaminated waste treatment facility (PWTF) is being made for the demonstration of the technology developed. Studies are in progress to find the criteria for waste products in disposal. The current procedures and strategy for the management of Pu-contaminated wastes at PNC are described as follows: current and future management; technology development including controlled air incineration, acid digestion, immobilization melting, dismantling, and liquid waste treatment; the Pu-contaminated waste treatment facility. (J.P.N.)

  3. Inhaled {sup 239}PuO{sub 2} in rats with pulmonary emphysema. II

    Energy Technology Data Exchange (ETDEWEB)

    Lundgren, D L; Mauderly, J L; Carlton, W W; Hahn, F F

    1988-12-01

    The modifying effects of pre-existing pulmonary emphysema on deposition, distribution, retention, and effects of inhaled {sup 239}PuO{sub 2} in the rat were investigated. The presence of emphysema in the rats tested was indicated by respiratory function measurements and confirmed microscopically. Initial lung burdens of {sup 239}Pu per kg body weight were less in rats with emphysema than in control rats; however, the retention of {sup 239}Pu was similar in emphysematous and control rats. Survival and lung tumor occurrence were similar in emphysematous and control rats exposed to {sup 239}PuO{sub 2}. We concluded that rats with pre-existing pulmonary emphysema were not more sensitive to the effects of inhaled {sup 239}PuO{sub 2} than control rats. (author)

  4. Molecular analysis of the interaction between the hematopoietic master transcription factors GATA-1 and PU.1

    DEFF Research Database (Denmark)

    Liew, Chu Wai; Rand, Kasper Dyrberg; Simpson, Raina J Y

    2006-01-01

    GATA-1 and PU.1 are transcription factors that control erythroid and myeloid development, respectively. The two proteins have been shown to function in an antagonistic fashion, with GATA-1 repressing PU.1 activity during erythropoiesis and PU.1 repressing GATA-1 function during myelopoiesis. It has...... also become clear that this functional antagonism involves direct interactions between the two proteins. However, the molecular basis for these interactions is not known, and a number of inconsistencies exist in the literature. We have used a range of biophysical methods to define the molecular details...... of the GATA-1-PU.1 interaction. A combination of NMR titration data and extensive mutagenesis revealed that the PU.1-Ets domain and the GATA-1 C-terminal zinc finger (CF) form a low affinity interaction in which specific regions of each protein are implicated. Surprisingly, the interaction cannot be disrupted...

  5. Plutonium-239, 240Pu and 210Po contents of tobacco and cigarette smoke

    International Nuclear Information System (INIS)

    Mussalo-Rauhamaa, H.; Jaakkola, T.

    1985-01-01

    The 239 Pu and 240 Pu found in the environment has mainly been produced by atmospheric nuclear tests. The accumulation of fallout Pu in man from inhalation and ingestion and its distribution in the body has previously been studied. Information about the accumulation is needed because of the expanding production of this highly radiotoxic substance. In the present work the Pu content of tobacco and cigarette smoke was determined to evaluate the contribution of smoking to total Pu intake by man. For comparison the 210 Po content of tobacco and smoke were analyzed. The release of 210 Po in tobacco smoke and the radiation dose for man have been widely studied because of the high incidence of lung cancer among smokers

  6. Behaviour of Pu-IV with various ion exchangers in solutions containing nitric acid and oxalates

    International Nuclear Information System (INIS)

    Walter, E.; Ali, S.A.

    1982-02-01

    The distribution of Pu-IV on the ion exchangers Dowex 50W-X8, Dowex 1-X8 und Dowex Chelating Resin Al-X8 in the presence of various concentrations of nitric acid and oxalate were investigated. The results indicate that nitric acid and oxalic acid influence each other during complexation of Pu-IV with oxalate ions solutions containing nitric acid it is not possible to neglect the formation of Pu-IV nitrate complexes. The complex Pu(IV) (C 2 O 4 ) 3 2 - only is formed in solutions containing low nitric acid and high oxalic acid concentrations. The separation of Pu-IV in Dowex Chelating Resin from nitric acid solution in the presence of higher oxalate concentrations is possible, provided that the nitric acid concentration is lower than 0.25 molar [fr

  7. Simultaneous measurement of {sup 239}Pu, {sup 240}Pu, {sup 241}Pu, and {sup 242}Pu by high resolution inductively coupled plasma mass spectrometer (HR ICP-MS) in marine sediments; Mesure des isotopes du plutonium des sediments marins par spectrometrie de masse a plasma couple inductivement haute resolution (HR ICP-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Bruneau, F

    1999-07-01

    Transuranics elements are of particular interest in radioecological studies because of their radiotoxicity and their potential use to decipher source fingerprints and transport processes. The simultaneous measurement of {sup 239}Pu, {sup 240}Pu, {sup 241}Pu, and {sup 242}Pu in environmental samples requires a specific chemical procedure. This work deals with an analytical procedure which yields a very high grade of purification of Pu suitable for ultra low level detection by HR ICP-MS, from marine sediments. After the elimination of major elements (Fe, Al, Mg...) by a first chromatographic separation, a new device of purification by solvent extraction and concentration by a second chromatographic separation is used to obtain a concentrated and high purified solution of plutonium. The chemical procedure have been validated on IAEA certified sediment samples and on sediment samples collected in the roads of Cherbourg which had been previously analysed by other techniques (a spectrometry and thermo-ionisation mass spectrometer). (author)

  8. Gamma-ray Output Spectra from 239 Pu Fission

    International Nuclear Information System (INIS)

    Ullmann, John

    2015-01-01

    Gamma-ray multiplicities, individual gamma-ray energy spectra, and total gamma energy spectra following neutron-induced fission of 239 Pu were measured using the DANCE detector at Los Alamos. Corrections for detector response were made using a forward-modeling technique based on propagating sets of gamma rays generated from a paramaterized model through a GEANT model of the DANCE array and adjusting the parameters for best fit to the measured spectra. The results for the gamma-ray spectrum and multiplicity are in general agreement with previous results, but the measured total gamma-ray energy is about 10% higher. A dependence of the gamma-ray spectrum on the gamma-ray multplicity was also observed. Global model calculations of the multiplicity and gamma energy distributions are in good agreement with the data, but predict a slightly softer total-energy distribution

  9. Hydroxyurea reaction with HNO2 and Pu(III) stabilization

    International Nuclear Information System (INIS)

    Zhu Zhaowu; He Jianyu; Zhang Zefu; Zheng Weifang; Song Tianbao; Lin Min

    2004-01-01

    Reaction kinetics of hydroxyurea (HU) with HNO 2 in nitric acid solution is studied. The results show that the reaction rate follows the equation as: -dc(HNO 2 )/dt=k 0 c(HNO 2 )c 1.1 (HNO 3 ) c 0 (HU), where k 0 =(0.18±0.01)L 1.1 ·mol -1.1 ·s -1 at 10 degree C and c(HNO 2 )=5 mmol/L; the activation energy is deduced to be about 63 kJ/mol. The reaction appears zero order relative to HU. Kinetic study performed at various NaNO 3 solutions shows that salt ions have little effect on the reaction rate. Excess HU can stabilize Pu(III) well in nitric solutions

  10. DOE Plutonium Disposition Study: Pu consumption in ALWRs

    International Nuclear Information System (INIS)

    1993-01-01

    The Department of Energy (DOE) has contracted with Asea Brown Boveri-Combustion Engineering (ABB-CE) to provide information on the capability of ABB-CE's System 80 + Advanced Light Water Reactor (ALWR) to transform, through reactor burnup, 100 metric tonnes (MT) of weapons grade plutonium (Pu) into a form which is not readily useable in weapons. This information is being developed as part of DOE's Plutonium Disposition Study, initiated by DOE in response to Congressional action. This document, Volume 1, presents a technical description of the various elements of the System 80 + Standard Plant Design upon which the Plutonium Disposition Study was based. The System 80 + Standard Design is fully developed and directly suited to meeting the mission objectives for plutonium disposal. The bass U0 2 plant design is discussed here

  11. The disproportionation of Pu4+ in nitric acid solutions

    International Nuclear Information System (INIS)

    Toth, L.M.; Bell, J.T.; Friedman, H.A.

    1990-01-01

    The Pu 4+ disproportionation equilibrium in nitric acid has been examined at ≤25deg C to extend our understanding and predictive ability with regard to species distribution under these conditions. Vis/UV absorption spectrophotometry has been used in a conventional manner to determine the concentrations of the various plutonium species. Values for the overall equilibrium quotient at 5, 15, and 25deg C were determined to be 0.098, 3.46, and 58.8, respectively, at zero ionic strength. From these values, the enthalpy of the reaction was found to be +52.7 kcal (220 kJ)/mol. The excellent reproducibility of the equilibrium quotients, even while parameters such as acid, nitrate ion and plutonium concentrations were changed, lend confidence to future predictive calculations regarding this reaction. (orig.)

  12. Fast reactor calculational route for Pu burning core design

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, S. [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1998-01-01

    This document provides a description of a calculational route, used in the Reactor Physics Research Section for sensitivity studies and initial design optimization calculations for fast reactor cores. The main purpose in producing this document was to provide a description of and user guides to the calculational methods, in English, as an aid to any future user of the calculational route who is (like the author) handicapped by a lack of literacy in Japanese. The document also provides for all users a compilation of information on the various parts of the calculational route, all in a single reference. In using the calculational route (to model Pu burning reactors) the author identified a number of areas where an improvement in the modelling of the standard calculational route was warranted. The document includes comments on and explanations of the modelling assumptions in the various calculations. Practical information on the use of the calculational route and the computer systems is also given. (J.P.N.)

  13. Interaction of Np(4) and Pu(4) with diisoamylphosphoric acid

    International Nuclear Information System (INIS)

    Sokhina, L.P.; Rovnyj, S.I.; Goncharuk, L.V.; Sladkova, M.V.; Tyumentseva, L.M.

    1988-01-01

    Interaction of neptunium (4) and plutonium (4) with diisoamylphosphoric acid (HD) in nitric acid solutions is investigated. It is ascertained that depending on mole ratio of HD and Np(Pu) in solution three types of compounds: Me (NO 3 ) 2 D 2 , Me(NO 3 ) 2 D 2 ·2HD and Me(NO 3 ) 2 D 2 ·4HD, are formed. The solubility of neptunium (plutonium) diisoamylphosphates in nitric acid, oxalate, carbonate and organic solutions, is determined. The possibility of the compound depositions in the extraction equipment should be taken into account in the process of spent fuel regeneration, when 30% HD solutions in n-paraffins are used as extractants

  14. Electronic structure of nitrides PuN and UN

    Science.gov (United States)

    Lukoyanov, A. V.; Anisimov, V. I.

    2016-11-01

    The electronic structure of uranium and plutonium nitrides in ambient conditions and under pressure is investigated using the LDA + U + SO band method taking into account the spin-orbit coupling and the strong correlations of 5 f electrons of actinoid ions. The parameters of these interactions for the equilibrium cubic structure are calculated additionally. The application of pressure reduces the magnetic moment in PuN due to predominance of the f 6 configuration and the jj-type coupling. An increase in the occupancy of the 5 f state in UN leads to a decrease in the magnetic moment, which is also detected in the trigonal structure of the UN x β phase (La2O3-type structure). The theoretical results are in good agreement with the available experimental data.

  15. Energy balance and deformation at scission in 240Pu fission

    Directory of Open Access Journals (Sweden)

    Manuel Caamaño

    2017-07-01

    Full Text Available The experimental determination of the total excitation energy, the total kinetic energy, and the evaporation neutron multiplicity of fully identified fragments produced in transfer-induced fission of 240Pu, combined with reasonable assumptions, permits to extract the intrinsic and collective excitation energy of the fragments as a function of their atomic number, along with their quadrupole deformation and their distance at scission. The results show that the deformation increases with the atomic number, Z, except for a local maximum around Z=44 and a minimum around Z=50, associated with the effect of deformed shells at Z∼44, N∼64, and spherical shells in 132Sn, respectively. The distance between the fragments also shows a minimum around Z1=44, Z2=50, suggesting a mechanism that links the effect of structure with the length of the neck at scission.

  16. Preparation and characterization of 238Pu-ceramics for radiation damage experiments

    International Nuclear Information System (INIS)

    DM Strachan; RD Scheele; WC Buchmiller; JD Vienna; RL Sell; RJ Elovich

    2000-01-01

    As a result of treaty agreements between Russia and the US, portions of their respective plutonium and nuclear weapons stockpiles have been declared excess. In support of the US Department of Energy's 1998 decision to pursue immobilization of a portion of the remaining Pu in a titanate-based ceramic, the authors prepared nearly 200 radiation-damage test specimens of five Pu- and 238 Pu-ceramics containing 10 mass% Pu to determine the effects of irradiation from the contained Pu and U on the ceramic. The five Pu-ceramics were (1) phase-pure pyrochlore [ideally, Ca(U, Pu)Ti 2 O 7 ], (2) pyrochlore-rich baseline, (3) pyrochlore-rich baseline with impurities, (4) phase-pure zirconolite [ideally Ca(U, Pu)Ti 2 O 7 ], and (5) a zirconolite-rich baseline. These ceramics were prepared with either normal weapons-grade Pu, which is predominantly 239 Pu, or 238 Pu. The 238 Pu accelerates the radiation damage relative to the 239 Pu because of its much higher specific activity. The authors were unsuccessful in preparing phase-pure (Pu, U) brannerite, which is the third crystalline phase present in the baseline immobilization form. Since these materials will contain ∼10 mass% Pu and about 20 mass% U, radiation damage to the crystalline structure of these materials will occur overtime. As the material becomes damaged from the decay of the Pu and U, it is possible for the material to swell as both the alpha particles and recoiling atoms rupture chemical bonds within the solid. As the material changes density, cracking, perhaps in the form of microcracks, may occur. If cracking occurs in ceramic that has been placed in a repository, the calculated rate of radionuclide release if the can has corroded would increase proportionately to the increase in surface area. To investigate the effects of radiation damage on the five ceramics prepared, the authors are storing the specimens at 20, 125, and 250 C until the 238 Pu specimens become metamict and the damage saturates. They will

  17. MSR (Pu converters) and MSBRs in commercial nuclear power stations

    International Nuclear Information System (INIS)

    Reichle, L.F.C.

    1977-01-01

    Molten Salt Reactors are likely to be the best way to achieve lowest-cost, safe, reliable and environmentally compatible commercial nuclear power in the early 1990's. This conclusion is based on work performed by the industrial members of the U.S. Molten Salt Group and by the Oak Ridge National Laboratory - both of whom are in general agreement on the status and prospects of Molten Salt Reactor technology. The MSBR Development Program is a 14-year program comprised of a 250 MWe MSTR (Molten Salt Test Reactor), a 1,000 MWe MSBR (Molten Salt Breeder Reactor) Demonstration Plant, and related development work. Plutonium from LWRs will fuel MSR (Pu Converters) which, in turn, will produce U-233 to fuel MSBRs. Because of the low inventory of fissile material in MSRs, a given amount of Pu will start-up many more MSRs than LMFBRs or GCFRs. MSRs can be expected to produce energy at a cost that will be competitive with LWRs before LMFBRs or GCFRs. They will use less uranium and require less enrichment. They will have a much lower development cost. They have the potential of producing high-temperature process heat. MSRs use a fluid fuel, and therefore eliminate the high cost of fuel fabrication. They have on-stream refueling and high thermal efficiency. They will have construction costs comparable to LWRs. MSRs have relative safety and environmental advantages, such as no possibility of a LOCA, low inventory of fissile material, continuous removal of fission products and on-site storage of spent fuel wastes

  18. Detailed spectroscopy in the superdeformed second minimum of 240Pu

    International Nuclear Information System (INIS)

    Thirolf, P.G.; Gassmann, D.; Habs, D.; Chromik, M.J.; Eisermann, Y.; Graw, G.; Hertenberger, R.; Maier, H.J.; Metz, A.; Reiter, P.

    2000-01-01

    Complete text of publication follows. Superdeformed prolate nuclei, having an axis ratio of about 2:1, have first been discovered in fission isomers in the actinide region almost 40 years ago by Polikanov et al.. Their interpretation of being the result of microscopic shell corrections on top of the macroscopic liquid drop potential leading to a second minimum in the nuclear potential energy surface is well established. 240 Pu with its 3.7 ns fission isomer may be regarded as the prototype nucleus for spectroscopic studies of superdeformed actinide nuclei since the identification of the ground state rotational band in conversion electron measurements [1]. Though from the knowledge on excited states in the first minimum and previous measurements in the second minimum low-lying collective excitations in the second minimum low-lying collective excitations in the second well of 240 Pu can be expected, none of them has been experimentally identified so far. Quite surprisingly, no low-lying collective quadrupole excitations could be observed in a recent detailed high-resolution and high-efficiency γ-spectroscopy experiment [2]. Complementary information could be obtained in conversion electron measurements in coincidence with isomeric fission performed at the Garching Accelerator Laboratory, resulting in the first identification of the lowest β-vibrational band [3]. In a combined analysis of the γ-spectroscopic and conversion electron data conversion coefficients α K or limits on α K could be deduced, thus allowing to determine the multipolarities of the transitions. A predominant population of negative parity states in the second well could be observed that can be explained by the filtering function of the inner and outer fission barrier. Complementary transmission resonance measurements have been performed, yielding new information on the fine structure of (β-)vibrational multi-phonon states. A new method could be established to determine the excitation energy of

  19. Mechanical resuspension of 239Pu from unpaved roads

    International Nuclear Information System (INIS)

    Hodgin, C.R.

    1982-01-01

    The impacts of resuspended plutonium from two unpaved roads at the Rocky Flats Plant on nearby air samplers were investigated. Because the sources were complex fugitive dust emitters and because of the small source-receptor distances, traditional dispersion modeling techniques could not be employed. Thus two specialized techniques, one for fugitive dust emissions and one for near distance dispersion, were developed and used to calculate atmospheric dust concentrations at the subject air samplers. Atmospheric 239 Pu impacts were then determined from measurements of plutonium concentrations in the resuspendible dust on the road surfaces. As a final step in the process the calculated plutonium impacts were compared to the 1980 annual average 239 Pu concentration at four samplers. The impact calculated for the Gunnery Range Road represented 2.1 percent of the observed annual concentration, with a 95 percent confidence interval of 1.1 to 7.9 percent. The Southeast Perimeter Road produced a more substantial effect with a point estimate of 3.8 percent. The 95 percent confidence interval for this source was 2.0 to 9.1 percent. The combined impact of the two roads on the subject samplers was 5.9 percent of the observed plutonium concentration, with a 95 percent confidence interval of 3.2 to 17.0 percent. Thus it was shown that fugitive plutonium emissions from the Gunnery Range Road and Southeast Perimeter Road are not substantial contributors to the plutonium concentrations observed at the subject samplers. Even an increase in dust control efficiency to 90 percent (as with paving) would result in only a four percent decrease in the overall atmosperic plutonium concentration at the site

  20. U.S.-Russian experts NATO collaborative research grant exchange visit meeting on excess Pu ceramics formulations and characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Jardine, L.J., LLNL

    1998-11-24

    This document contains the agenda and meeting notes. Topics of discussion included US Pu disposition ceramics activities, Russian experience and proposals in Pu ceramics, and development of possible Russian ceramic proposals or collaborations.

  1. 137Cs, 239+24Pu and 24Pu/239Pu atom ratios in the surface waters of the western North Pacific Ocean, eastern Indian Ocean and their adjacent seas

    International Nuclear Information System (INIS)

    Yamada, Masatoshi; Zheng Jian; Wang Zhongliang

    2006-01-01

    Surface seawater samples were collected along the track of the R/V Hakuho-Maru cruise (KH-96-5) from Tokyo to the Southern Ocean. The 137 Cs activities were determined for the surface waters in the western North Pacific Ocean, the Sulu and Indonesian Seas, the eastern Indian Ocean, the Bay of Bengal, the Andaman Sea, and the South China Sea. The 137 Cs activities showed a wide variation with values ranging from 1.1 Bq m -3 in the Antarctic Circumpolar Region of the Southern Ocean to 3 Bq m -3 in the western North Pacific Ocean and the South China Sea. The latitudinal distributions of 137 Cs activity were not reflective of that of the integrated deposition density of atmospheric global fallout. The removal rates of 137 Cs from the surface waters were roughly estimated from the two data sets of Miyake et al. [Miyake Y, Saruhashi K, Sugimura Y, Kanazawa T, Hirose K. Contents of 137 Cs, plutonium and americium isotopes in the Southern Ocean waters. Pap Meteorol Geophys 1988;39:95-113] and this study to be 0.016 yr -1 in the Sulu and Indonesian Seas, 0.033 yr -1 in the Bay of Bengal and Andaman Sea, and 0.029 yr -1 in the South China Sea. These values were much lower than that in the coastal surface water of the western Northwest Pacific Ocean. This was likely due to less horizontal and vertical mixing of water masses and less scavenging. 239+24 Pu activities and 24 Pu/ 239 Pu atom ratios were also determined for the surface waters in the western North Pacific Ocean, the Sulu and Indonesian Seas and the South China Sea. The 24 Pu / 239 Pu atom ratios ranged from 0.199 ± 0.026 to 0.248 ± 0.027 on average, and were significantly higher than the global stratospheric fallout ratio of 0.18. The contributions of the North Pacific Proving Grounds close-in fallout Pu were estimated to be 20% for the western North Pacific Ocean, 39% for the Sulu and Indonesian Seas and 42% for the South China Sea by using the two end-member mixing model. The higher 24 Pu / 239 Pu atom ratios

  2. Chronic cigarette smoke exposure increases the pulmonary retention and radiation dose of 239Pu inhaled as 239PuO2 by F344 rats

    International Nuclear Information System (INIS)

    Finch, G.L.; Lundgren, D.L.; Barr, E.B.; Chen, B.T.; Griffith, W.C.; Hobbs, C.H.; Hoover, M.D.; Nikula, K.J.; Mauderly, J.L.

    1998-01-01

    As a portion of a study to examine how chronic cigarette smoke exposure might alter the risk of lung tumors from inhaled 239 PuO 2 in rats, the effects of smoke exposure on alpha-particle lung dosimetry over the life-span of exposed rats were determined. Male and female rats were exposed to inhaled 239 PuO 2 alone or in combination with cigarette smoke. Animals exposed to filtered air along served as controls for the smoke exposure. Whole-body exposure to mainstream smoke diluted to concentrations of either 100 or 250 mg total particulate matter m -3 began at 6 wk of age and continued for 6 h d -1 , 5 d wk -1 , for 30 mo. A single, pernasal, acute exposure to 239 PuO 2 was given to all rats at 12 wk of age. Exposure to cigarette smoke caused decreased body weight gains in a concentration dependent manner. Lung-to-body weight ratios were increased in smoke-exposed rats. Rats exposed to cigarette smoke before the 239 PuO 2 exposure deposited less 239 Pu in the lung than did controls. Except for male rats exposed to LCS, exposure to smoke retarded the clearance of 239 Pu from the lung compared to control rats through study termination at 870 d after 239 PuO 2 exposure. Radiation doses to lungs were calculated by sex and by exposure group for rats on study for at least 360 d using modeled body weight changes, lung-to-body weight ratios, and standard dosimetric calculations. For both sexes, estimated lifetime radiation doses from the time of 239 PuO 2 exposure to death were 3.8 Gy, 4.4 Gy, or 6.7 Gy for the control, LCS, or HCS exposure groups, respectively. Assuming an approximately linear dose-response relationship between radiation dose and lung neoplasm incidence, approximate increases of 20% or 80% in tumor incidence over controls would be expected in rats exposed to 239 PuO 2 and LCS or 239 PuO 2 and HCS, respectively

  3. Risk estimates for lung tumors from inhaled 239PuO2, 238PuO2, and /sup 239Pu/(NO3)4 in beagle dogs

    International Nuclear Information System (INIS)

    Dagle, G.E.; Park, J.F.; Gilbert, E.S.; Weller, R.E.

    1988-06-01

    Lung-cancer risks are being studied in beagle dogs given single exposures to aerosols of 239 PuO 2 , 238 PuO 2 , or 239 Pu(NO 3 ) 4 . A major objective of these studies is to examine the risk of lung cancer relative to the specific activity of the radionuclide, rate of dose accumulation due to differences in solubilities of the radionuclides, and the presence of competing risk from extrapulmonary lesions. Dose-response relationships were studied for the three groups of dogs, with analyses specifically designed to evaluate differences in response. Based on estimated cumulative dose to the lung, risks were found to differ significantly among the radionuclides; they were highest for 239 Pu(NO 3 ) 4 and lowest for 238 PuO 2 . A model in which the risk was assumed to be a pure quadratic function of dose fit the data much better than a pure linear model. Currently, all three groups of dogs can be compared only to 10 years after exposure. However, it is apparent that the average cumulative dose to the lung may not be an adequate predictor of lung-cancer risk for different isotopic and physicochemical forms of plutonium. 13 refs., 2 tabs

  4. Thermodynamic assessment of the LiF–ThF4–PuF3–UF4 system

    NARCIS (Netherlands)

    Capelli, E.; Benes, O.; Konings, R.J.M.

    2015-01-01

    The LiF–ThF4–PuF3–UF4 system is the reference salt mixture considered for the Molten Salt Fast Reactor (MSFR) concept started with PuF3. In order to obtain the complete thermodynamic description of this quaternary system, two binary systems (ThF4–PuF3 and UF4–PuF3) and two ternary systems

  5. The AS-76 interlaboratory experiment on the alpha spectrometric determinaion of Pu-238. Part 3: Preparation and characterization of samples

    International Nuclear Information System (INIS)

    Bortels, G.; Broothaerts, J.; Bievre, P. de

    1980-01-01

    Four plutonium samples containing 0.2, 0.8, 1.6 and 0.9 atom % of 238 Pu have been prepared for the Interlaboratory Experiment AS-76. Of these three were input solutions from a reprocessing plant. The fourth sample was from a plutonium product solution. These samples have been characterized by two alpha spectrometry laboratories and two mass spectrometry laboratories to certify the ratio of alpha activities 238 Pu/( 239 Pu + 240 Pu) and the isotopic composition, respectively

  6. Effect of microdose distribution on chromosome aberration frequency in liver cells of the Chinese hamster following exposure to 239PuO2 or 238PuO2 particles

    International Nuclear Information System (INIS)

    Brooks, A.L.; Peters, R.F.; Retherford, J.C.

    1974-01-01

    Chinese hamsters were injected intravenously with 239 PuO 2 or 238 PuO 2 particles of known size or with 238 Pu citrate to determine the effect of particle size and specific activity on the frequency and distribution of chromosome damage in the liver. Three particle sizes were used in the 239 PuO 2 experiment: 0.15, 0.44, and 0.89 μm, and all animals were injected with a constant activity, 5 x 10 -4 muCi 239 Pu/gm body weight. The 238 PuO 2 was injected in three particle sizes, 0.17, 0.41, and 1.1 μm and at three activity levels. The 238 Pu citrate was injected at 5 x 10 -3 muCi 238 Pu/gm body weight. Hamsters injected with 239 PuO 2 were sacrificed at 15, 42, and 122 days after injection and those injected with either 238 PuO 2 or 238 Pu citrate were sacrificed 12 days after injection. The number of alpha tracks/star increased as a function of the particle size injected. A change in particle size with time was noted as smaller particles were aggregated into larger ones by the phagocytic action of Kupffer cells. Injection of 239 PuO 2 and 238 PuO 2 produced a distribution of chromosome damage which was non-poison in nature. 239 PuO 2 produced increased damage with increasing average dose with some cells containing a large number of aberrations, but there was relatively little particle size effect. Conversely, aberration frequencies after 238 PuO 2 injection were inversely related to particle size and no cells were seen with large amounts of damage. The 238 Pu citrate produced 6 x 10 -3 aberrations/cell/rad which was a higher rate than observed for 238 Pu particles. Risk for the production of cellular damage in the liver was greater per μCi following injection of either 238 Pu or 239 Pu citrate than it was following deposition of the same amount of 239 PuO 2 or 238 PuO 2 particles. (U.S.)

  7. Pu oxidation state distributions in suspensions of the Mont Terri Opalinus Clay isolate Sporomusa sp. MT-2.99

    Energy Technology Data Exchange (ETDEWEB)

    Moll, Henry [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biogeochemistry; Cherkouk, Andrea [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). HZDR Young Investigator Group; Bok, Frank [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes

    2017-06-01

    The time-dependent {sup 242}Pu oxidation state distribution in the presence of Sporomusa sp. cells as a function of pH with or without Na-pyruvate was analyzed. In all cases, the presence of bacterial cells enhanced removal of Pu from solution and accelerated Pu interaction reactions, e.g. biosorption and bioreduction.

  8. Pu oxidation state distributions in suspensions of the Mont Terri Opalinus Clay isolate Sporomusa sp. MT-2.99

    International Nuclear Information System (INIS)

    Moll, Henry; Cherkouk, Andrea; Bok, Frank

    2017-01-01

    The time-dependent "2"4"2Pu oxidation state distribution in the presence of Sporomusa sp. cells as a function of pH with or without Na-pyruvate was analyzed. In all cases, the presence of bacterial cells enhanced removal of Pu from solution and accelerated Pu interaction reactions, e.g. biosorption and bioreduction.

  9. Influence of initial lung deposit on absorption parameters of Pu and am: application to (U, Pu)O2 powder after inhalation in the baboon

    International Nuclear Information System (INIS)

    Rateau-matton, S.R.M.; Abram, M.C.; Rouit, E.; Grillon, G.; Legall, B.L.G.; Van Der Meeren, A.V.D.

    2006-01-01

    Full text of publication follows: In cases of contamination by inhalation, risk assessment would be performed taking into account recommendations of the International Commission of Radiological Protection (ICRP) Human Respiratory Tract Model (H.R.T.M.) described in Publication 66 (ICRP 66, 1994). The use of absorption parameter values specific to each component is recommended when available for dose calculation in order to provide a more realistic assessment of risk. The solubility of Pu and Am deposited in the respiratory tract after inhalation is a relevant parameter that can aid the identification of target organs. The aim of this study is to show the influence of the initial lung deposit (I.L.D.) on absorption parameters after inhalation of Mixed oxides (Mox) powder (7.14 % Pu w/w) in baboons. Daily urinary excretion of Pu/Am was measured for 3 months which allowed the estimation of the removal of the soluble fraction from lungs to blood and in particular a proportion of absorption parameters. Urinary excretion on 3 -month period were represented by biphasic curves which were directly reliable to physicochemical properties of compounds. Males baboon were exposed to I.L.D.: 40 to 860 kBq. Results obtained show that urinary excretions progress in the reverse order of I.L.D. Moreover, significant differences in the behaviour of Pu and Am were also observed in the target organs (liver and skeleton) and especially Am was more soluble than Pu for the compound studied. So, hypothesis of a more important dissolution of Am compare to Pu combines to a special affinity of Am for target organs seem to be involve. This result was very important in case of dismantling operation mainly in the usury of fuel since 241 Am is a filiation product of 241 Pu. In conclusion, this work contributes to support the usefulness of experimental data in radioprotection to estimate level of radiological exposition of worker. (authors)

  10. The impact of Pu speciation on distribution coefficients in Mayak soil.

    Science.gov (United States)

    Skipperud, L; Oughton, D; Salbu, B

    2000-08-10

    To assess the long-term consequences when radionuclides are released into the environment, information on the source term, transport and transformation processes, interaction with soils (KD) and biological uptake (CF) is needed. Among the artificial radionuclides released to the environment by nuclear activities, the transuranium elements are a major concern, due to very long half-lives and their accumulation in bone as well as high radiotoxicity. Plutonium has been produced in greater quantity than other transuranic elements, however, environmental assessments are complicated by the complex environmental behaviour. Physico-chemical forms of Pu will determine the interactions with soils and, thus, the degree to which soils can act as a sink or a potential diffuse source of contaminants. In the present work, dynamic tracer experiments have been performed where different Pu-species are added to a 'Mayak soil-rainwater system' to obtain information on KD values. After a defined contact time, the samples where then sequentially extracted and results are used in a dynamic box model to estimate interaction and fixation rates. The interaction of all Pu-species with soils seems to be rapid and follows a two-step reaction. Up to contact times of a few weeks, the KD for Pu(III,IV) (730 +/- 240 l/kg) is approximately one order of magnitude higher than for Pu(V,VI) (90 +/- 20 l/kg) and Pu(III,IV)-organic (40-60 l/kg). After 3 months contact time, the KD in only the two organic-bound Pu-species were significantly lower. This shows that the initial association with the soil is dependent on the Pu-species in the rainwater. After only 1 h of contact, between 33 and 40% of the plutonium was strongly bound to the soil components, i.e. only extractable with strong HNO3. The extraction of soil-bound Pu followed a similar pattern for all the original species, suggesting that the next step of Pu interaction mechanism with soil was rather independent of the original species. For both the

  11. Modeling of Pu(IV) extraction and HNO3 speciation in nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    De-Sio, S.

    2012-01-01

    The PUREX process is a solvent extraction method dedicated to the reprocessing of irradiated nuclear fuel in order to recover pure uranium and plutonium from aqueous solutions of concentrated nitric acid. The tri-n-butylphosphate (TBP) is used as the extractant in the organic phase. The aim of this thesis work was to improve the modeling of liquid-liquid extraction media in nuclear fuel reprocessing. First, Raman and 14 N NMR measurements, coupled with theoretical calculations based on simple solutions theory and BIMSA modeling, were performed in order to get a better understanding of nitric acid dissociation in binary and ternary solutions. Then, Pu(IV) speciation in TBP after extraction from low nitric acid concentrations was investigated by EXAFS and vis-NIR spectroscopies. We were able to show evidence of the extraction of Pu(IV) hydrolyzed species into the organic phase. A new structural study was conducted on An(VI)/TBP and An(IV)/TBP complexes by coupling EXAFS measurements with DFT calculations. Finally, extraction isotherms modeling was performed on the Pu(IV)/HNO 3 /H 2 O/TBP 30%/dodecane system (with Pu at tracer scale) by taking into account deviation from ideal behaviour in both organic and aqueous phases. The best modeling was obtained when considering three plutonium (IV) complexes in the organic phase: Pu(OH) 2 (NO 3 ) 2 (TBP) 2 , Pu(NO 3 ) 4 (TBP) 2 and Pu(NO 3 ) 4 (TBP) 3 . (author) [fr

  12. Measurement of PuO2 spot in the mixed-oxide fuels

    International Nuclear Information System (INIS)

    Yokosuka, Yoshifumi; Kaneda, Kenichiro; Ishikawa, Eiji; Nakajima, Katsuaki; Kashima, Sadamitsu

    1974-01-01

    The homogeneity of mixed-oxide fuel is evaluated with the maximum diameter of PuO 2 spots. PuO 2 spot distribution is influenced by fuel production process and raw materials used. Analytical measurement of the PuO 2 spot distribution was carried out. α-autoradiograph was taken with nitrocellulose film as a detector. The film was exposed for 15 and 30 minutes to the sample pellets, and etched in 10% NaOH for 2 minutes at 60 0 C. Measurement of PuO 2 spots was performed manually with a projector. PuO 2 spot distribution was measured. There is no difference of spot distribution owing to the location in a pellet. However some discrepancy exists in spot number and maximum diameter between surface and inner part. This phenomenon is explained by considering that the diffusion on surface is more effective than in inner part in sintering process. Three pellets were taken out from a lot at random, and α-autoradiograph was taken longitudinally with a pellet and transversely with the others. PuO 2 spot number counted from three autoradiographs was about 150/cm 2 , and the standard deviation was about 1.5. No difference was observed among them. Concerning the influence of mixing method on PuO 2 spot formation, three methods were examined; ball mill mixing (with and without lining) and Kneader mixing. Kneader mixing gave the worst results in maximum spot diameter and spot distribution range. (Tai, I.)

  13. Change Spectroscopic, thermal and mechanical studies of PU/PVC blends

    Energy Technology Data Exchange (ETDEWEB)

    Hezma, A.M. [Spectroscopy Department, Physics Division, National Research Center, Giza (Egypt); Elashmawi, I.S. [Spectroscopy Department, Physics Division, National Research Center, Giza (Egypt); Physic Department, Faculty of Science, Taibah University, Al-Ula (Saudi Arabia); Rajeh, A., E-mail: a.rajeh88@yahoo.com [Physic Department, Faculty of Science, Amran University, Sa' dah (Yemen); Physics Department, Faculty of science, Mansoura University, Mansoura (Egypt); Kamal, Mustafa [Physics Department, Faculty of science, Mansoura University, Mansoura (Egypt)

    2016-08-15

    Blends of polyurethane (PU) and polyvinyl chloride (PVC) with different concentrations were prepared by casting method. The effects of PU on PVC blends was examined by Fourier transform-infrared (FTIR), Ultra-violet visible studies (UV/VIS.), X-ray diffraction (XRD), Thermogravimetric (TGA), Differential scanning calorimetry (DSC), and mechanical properties (stress–strain curve). The interaction between PU and PVC was examined by FT-IR through the absorbance of the N–H groups and was correlated to mechanical/thermal properties. Ultra-violet visible said that optical energy gap decrease with increasing concentration of PU. Differential scanning calorimetry results was observed a single glass transition temperature (T{sub g}) for blends this confirming existence miscibility within the blends. The causes for best thermal stability of some blends may be described by measurements of interactions between C=O groups of PU and the α-hydrogen of PVC or a dipole–dipole –C=O..Cl–C– interactions. Significant alterations in FTIR, X-ray and DSC examination shows an interactions between blends had good miscibility. X-ray shows some alterations in the intensity with additional PU. PU change the mechanical behavior of PVC through of the blends. When polyurethane content increase causes polyvinyl chloride tensile strength decreases and elongation at break increase.

  14. Thermodynamic assessments and inter-relationships between systems involving Al, Am, Ga, Pu, and U

    Energy Technology Data Exchange (ETDEWEB)

    Perron, A., E-mail: perron1@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Turchi, P.E.A.; Landa, A. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Oudot, B.; Ravat, B.; Delaunay, F. [CEA-Centre de Valduc, 21120, Is sur Tille (France)

    2016-12-15

    A newly developed self-consistent CALPHAD thermodynamic database involving Al, Am, Ga, Pu, and U is presented. A first optimization of the slightly characterized Am-Al and completely unknown Am-Ga phase diagrams is proposed. To this end, phase diagram features as crystal structures, stoichiometric compounds, solubility limits, and melting temperatures have been studied along the U-Al → Pu-Al → Am-Al, and U-Ga → Pu-Ga → Am-Ga series, and the thermodynamic assessments involving Al and Ga alloying are compared. In addition, two distinct optimizations of the Pu-Al phase diagram are proposed to account for the low temperature and Pu-rich region controversy. The previously assessed thermodynamics of the other binary systems (Am-Pu, Am-U, Pu-U, and Al-Ga) is also included in the database and is briefly described in the present work. Finally, predictions on phase stability of ternary and quaternary systems of interest are reported to check the consistency of the database.

  15. Biokinetics aand dosimetry of inhaled 238PuO2 in the beagle dog: An update

    International Nuclear Information System (INIS)

    Guilmette, R.A.; Griffith, W.C.; Diel, J.H.

    1994-01-01

    The temporal and spatial distributions of 238 Pu have been measured during the course of a dose-response study of the biological effects of inhaled 238 PuO 2 in Beagle dogs. These measurements were done on the dose-response study animals, as well as a separate group of dogs exposed to similar aerosols and killed serially out to 4 y after exposure. The data from this latter group provided the basis for the development of a biokinetic/dosimetric model for 238 PuO 2 in dogs. Since the publication of this model, several important findings have been made that affected the dosimetric evaluations. The first involved the discovery of significant quantities of natural uranium (U) in the feces samples. The U was measured with the plutonium (Pu), which inflated the values for purported Pu in feces. The second finding involved the addition of Pu biokinetics data from the dose-response dogs, which increased the period of observation from 4 y to 15 y; these later data were not consistent with the earlier model predictions. The purpose of this investigation was (1) to remove the analytical bias in the 238 Pu radiochemical data due to the U and (2) to modify the original model of Mewhinney and Diel, taking into account all data from both studies

  16. The concentrations of sup(239.240)Pu in foods of the Japanese

    International Nuclear Information System (INIS)

    Okabayashi, Hiroyuki; Watanabe, Mineo; Takizawa, Yukio.

    1981-01-01

    Measurements of the amounts of sup(239.240)Pu in total daily diet and in marine foods were conducted to estimate the dietary intake of sup(239.240)Pu in the Japanese. The average concentrations of sup(239.240)Pu in total diet of various places in Japan were 96 fCi/day/person in 1968 and 50 fCi/day/person in 1969. It was found that the concentration of sup(239.240)Pu in total diet decreased with the decrease of radioactive fallout. The concentrations of sup(239.240)Pu in viscera and bone of marinefishes and in seaweeds were high. The average amount of dietary intake of sup(239.240)Pu from marine foods by the Japanese at present was about 9 fCi/day/person. It was estimated that the greater part of sup(239.240)Pu in total diet of the Japanese was due to the marine foods. (author)

  17. The removal of inhaled 239Pu from beagle dogs by bronchopulmonary lavage and chelation therapy

    International Nuclear Information System (INIS)

    Muggenburg, B.A.; Mewhinney, J.A.; Slauson, D.O.; Miglio, J.J.; Ruoff, L.; Mersch, S.; McClellan, R.O.

    1976-01-01

    The efficacy of bronchopulmonary lavage and chelatan therapy for removing 239 Pu from beagle dogs after inhalation of 239 Pu aerosols having different solubilities has been investigated. The four aerosols used were nebulized from a solution of 239 PuCl 4 and heat treated at temperatures of 325, 600, 900 and 1150 0 C. Groups of six beagle dogs were exposed to each of the aerosols. Subsequently, three dogs in each group were treated by lavage and intravenous injections of DTPA. The remaining three dogs in each group served as untreated controls. It was found that bronchopulmonary lavage treatment was effective in removing nearly half of the 239 Pu activity from the lung regardless of the aerosol production temperature. This early removal of 239 Pu activity resulted in a significant reduction in daily dose rate and therefore cumulative α dose to lung. The effectiveness of DTPA treatment depended on aerosol production temperature, and was effective in reducing accumulation of 239 Pu in liver and skeleton of the dogs that inhaled aerosols produced at 325 0 and 600 0 C by enhancing urinary excretion of 239 Pu. (U.K.)

  18. Contribution to the study of U-Ti and U-Pu-Ti carbides; Contribution a l'etude des carbures U-C-Ti et (U, Pu) - C-Ti

    Energy Technology Data Exchange (ETDEWEB)

    Milet, C A [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    After having discussed the reasons to use (U,Pu) carbides as fast reactor fuel, we examine the influence of the addition of titanium to these carbides. A preliminary study has been done on the system of U-C-Ti and some properties have been measured such as: density, thermal expansion, electrical resistivity, atmospheric corrosion and compatibility with stainless steel. The systems U-Pu-C-Ti (Pu/U + Pu equal to 15 per cent) and U-C-Ti have been found to be very similar. There exists a two phases region (U,Pu)C + TiC, an eutectic between (U,Pu)C and TiC for approximately 15 at %. The solubilities of U + Pu in TiC and of Ti in (U,Pu)C is less than 1 % at. The addition of titanium does not markedly change thermal expansion coefficients of (U,Pu)C. However the resistance to atmospheric corrosion and compatibility with stainless steel is improved. Thermal conductivity, calculated from electrical resistivity, has increased. On the other side, the density of fissile material is lowered. The combination of (U,Pu)C + TiC seems to be the most promising alloy for application as nuclear fuel. (author) [French] Apres avoir rappele les problemes poses par un combustible pour les reacteurs a neutrons rapides et l'interet des carbures U-Pu-C comme combustible, on examine l'influence de l'addition de titane dans ces carbures. Une etude preliminaire sur le systeme U-C-Ti a ete effectuee et quelques proprietes sont indiquees: densite, coefficients de dilatation, resistivite electrique, tenue a la corrosion atmospherique, compatibilite avec l'acier inoxydable. Le systeme U-Pu-C-Ti (Pu/U + Pu egal a 15 pour cent) presente de grandes analogies avec le systeme U-C-Ti. Il existe un domaine biphase (U,Pu)C + TiC, un eutectique entre (U,Pu)C et TiC pour environ 15 at % Ti; les solubilites de U + Pu clans TiC et de Ti dans (U,Pu)C sont inferieures a 1 at %. Par rapport a la phase (U,Pu)C, l'addition de titane est sans effets importants sur les coefficients de dilatation. Par contre la tenue a

  19. Application of a canine 238Pu dosimetry model to human bioassay data

    Energy Technology Data Exchange (ETDEWEB)

    Hickman, Jr., A. W. [Florida Univ., Gainesville, FL (United States)

    1991-08-01

    Associated with the use of 2238Pu in thermoelectric power sources for space probes and power supplies for cardiac devices is the potential for human exposure to 238Pu, primarily by inhalation. In the event of human internal exposure, a means is needed for assessing the level of intake and calculating radiation doses. Several bioassay/dosimetry models have been developed for 239Pu. However, results from studies with laboratory animals have indicated that the biokinetics, and therefore the descriptive models, of 238Pu are significantly different from those for 239Pu. A canine model accounting for these differences has been applied in this work to urinary excretion data from seven humans occupationally exposed to low levels of an insoluble 238Pu compound. The modified model provides a good description of the urinary excretion kinetics observed in the exposed humans. The modified model was also used to provide estimates of the initial intakes of 238Pu for the seven individuals; these estimates ranged from 4.5 nCi (170 Bq) to 87 nCi (3200 Bq). Autopsy data on the amount and distribution of 238Pu retained in the organs may be used in the future to validate or refute both these estimates and the assumptions used to formulate the human model. Modification of the human model to simulate an injection exposure to 239Pu gave patterns of retention in the organs and urinary excretion comparable to those seen previously in humans; further modification of the model using fecal data (unavailable for the subjects of this study) is indicated.

  20. Monte Carlo analysis of Pu-H2O and UO2-PuO2-H2O critical assemblies with ENDF/B-IV data

    International Nuclear Information System (INIS)

    Hardy, J. Jr.; Ullo, J.J.

    1981-04-01

    A set of critical experiments, comprising thirteen homogeneous Pu-H 2 O assemblies and twelve UO 2 -PuO 2 lattices, was analyzed with ENDF/B-IV data and the RCPO1 Monte Carlo program, which modeled the experiments explicitly. Some major data sensitivities were also evaluated. For the Pu-H 2 O assemblies, calculated K/sub eff/ averaged 1.011. The large (2.7%) scatter of K/sub eff/ values for these assemblies was attributed mostly to uncertainties in physical specifications since no clear trends of K/sub eff/ were evident and data sensitivities were insignificant. The UO 2 -PuO 2 lattices showed just one trend of K/sub eff/, which indicated an overprediction of U238 capture consistent with that observed for uranium-H 2 O experiments. There was however a approx. 1% discrepancy in calculated K/sub eff/ between the two sets of UO 2 -PuO 2 lattices studied

  1. Study of the number of neutrons produced by fission of {sup 239}Pu; Etude du nombre de neutrons produits par la fission de {sup 239}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Study of the number of neutrons produced by fission of {sup 239}Pu. The counting by coincidence of fissions and neutrons produced by these fissions allows the study of the variation of the mean number of neutrons emitted by {nu} fission. In the first chapter, it studied the variation of the mean number of neutrons emitted by {sup 239}Pu fission with the energy of the incident neutron. A description of the experiment is given: a spectrometer with a crystal of sodium chloride or beryllium (mounted on a goniometer) is used, a fission chamber containing 10 mg of {sup 239}Pu and the neutron detection system constituted of BF{sub 3} counters which are enriched in {sup 10}B. In the second part, the counting by coincidence of fissions and neutrons produced by the same fission and received by two different groups of counters allow the determination of a relationship between the root mean square and the average of neutron number produced by fission. The variation of the mean number of neutrons emitted by fission of {sup 239}Pu is studied when we change from a thermal spectra of neutrons to a fission spectra of incident neutrons. Finally, when separating in two different part the fission chamber, it is possible to measure the mean number of neutrons emitted from fission of two different sources. It compared the mean number of neutrons emitted by fission of {sup 239}Pu and {sup 233}U. (M.P.)

  2. Distribution and flux of 238Pu, 239,240Pu, 241Am, 137Cs and 210Pb to high arctic lakes in the Thule district (Greenland).

    Science.gov (United States)

    Eriksson, M; Holm, E; Roos, P; Dahlgaard, H

    2004-01-01

    Environmental samples (soil, sediment and lake water) in the Thule area (NW Greenland) have been studied to assess the contamination of radionuclides originating from a nuclear weapons accident (the Thule accident in 1968). Four lakes were chosen at different distances from the point of impact with the Thule air base community situated in between. The sedimentation rates in the lakes varied from 0.4 mm a(-1) (5 mg cm(-2) a(-1)) to 1.6 mm a(-1) (82 mg cm(-2) a(-1)). With these sedimentation rates, it is not possible to resolve the (239,240)Pu global fallout peak from a possible (239,240)Pu "accident" peak in the sediment depth profiles. However, the (239,240)Pu/(137)Cs and the (238)Pu/(239,240)Pu ratios agreed well with global fallout ratios, indicating that plutonium originating from the accident had not reached these lakes. This also indicates that the Thule air base community has probably only been exposed to radionuclides from the accident to a very limited extent. A limited study showed that (210)Pb could not be used as a normalizing nuclide to explain the transport of transuranic elements from the catchment area to the lake, i.e. (210)Pb has a different transport mechanism from that of the transuranic elements studied in this investigation.

  3. Determination of the neutron-induced fission cross section of {sup 242}Pu; Bestimmung des neutroneninduzierten Spaltquerschnitts von {sup 242}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Koegler, Toni Joerg

    2016-04-26

    Neutron induced fission cross sections of actinides like the Pu-isotopes are of relevance for the development of nuclear transmutation technologies. For {sup 242}Pu, current uncertainties are of around 21%. Sensitivity studies show that the total uncertainty has to be reduced to below 5% to allow for reliable neutron physics simulations. This challenging task was performed at the neutron time-of-flight facility of the new German National Center for High Power Radiation Sources at HZDR, Dresden. Within the TRAKULA project, thin, large and homogeneous deposits of {sup 235}U and {sup 242}Pu have been produced successfully. Using two consecutively placed fission chambers allowed the determination of the neutron induced fission cross section of {sup 242}Pu relative to {sup 235}U. The areal density of the Plutonium targets was calculated using the measured spontaneous fission rate. Experimental results of the fast neutron induced fission of {sup 242}Pu acquired at nELBE will be presented and compared to recent experiments and evaluated data. Corrections addressing the neutron scattering are discussed by using results of different neutron transport simulations (Geant 4, MCNP 6 and FLUKA).

  4. Routine radiochemical method for the determination of 90Sr, 238Pu, 239+240Pu, 241Am and 244Cm in environmental samples

    International Nuclear Information System (INIS)

    Ageyev, V.A.; Sajeniouk, A.D.

    2005-01-01

    Routine analytical procedures have been developed for the reliable simultaneous determination of 90 Sr, 238 Pu, 239+240 Pu, 241 Am and 242-244 Cm, Chernobyl derived radioisotopes and fallout after nuclear weapon tests in a wide range of environmental samples: soil (100-200 g), sediments, aerosols, water and vegetation. This procedure has been applied to thousands of soil and sediment samples and hundreds of biological and water samples taken in the exclusive zone of Chernobyl NPP and different regions of Ukraine from 1989 to the present. After the sample has been properly prepared and isotopic tracers added, plutonium, americium and curium are precipitated with calcium oxalate and then lanthanum fluoride. Plutonium is separated from americium and curium by anion-exchange. Americium and curium are separated from rare earths by cation-exchange with gradient elute α-hydroxy-iso-butyric acid. During projects by AQCS IAEA 'Evaluation of Methods for 90 Sr in a Mineral Matrix' and 'Proficiency Test for 239 Pu, 241 Pu and 241 Am Measurement in a Mineral Matrix' accuracy and precision for 90 Sr, 239 Pu and 241 Am by present procedure was evaluated. Advantages, difficulties and limitations of the method are discussed. (author)

  5. Phase equilibrium of PuO2-x - Pu2O3 based on first-principles calculations and configurational entropy change

    International Nuclear Information System (INIS)

    Minamoto, Satoshi; Kato, Masato; Konashi, Kenji

    2011-01-01

    Combination of an oxygen vacancy formation energy calculated using first-principles approach and the configurational entropy change treated within the framework of statistical mechanics gives an expression of the Gibbs free energy at large deviation from stoichiometry of plutonium oxide PuO 2 . An oxygen vacancy formation energy 4.20 eV derived from our previously first-principles calculation was used to evaluate the Gibbs free energy change due to oxygen vacancies in the crystal. The oxygen partial pressures then can be evaluated from the change of the free energy with two fitting parameters (a vacancy-vacancy interaction energy and vibration entropy change due to induced vacancies). Derived thermodynamic expression for the free energy based on the SGTE thermodynamic data for the stoichiometric PuO 2 and the Pu 2 O 3 compounds was further incorporated into the CALPHAD modeling, then phase equilibrium between the stoichiometric Pu 2 O 3 and non-stoichiometric PuO 2-x were reproduced.

  6. Study of phase equilibrium of Pu2O3-PuO2 system by the first-principles calculation and CALPHAD approach

    International Nuclear Information System (INIS)

    Minamoto, Satoshi; Kato, Masato; Konashi, Kenji

    2010-01-01

    A combination of a first-principles calculation, lattice dynamics and CALPHAD (CALculation of PHAse Diagrams) modeling is proven as a powerful tool so as to evaluate the Gibbs free energy and a phase equilibrium between compounds including large amount of vacancies. In this work, non-stoichiometric PuO 2-x (dioxide) and Pu 2 O 3 (sesquioxide) has been studied. An electron cohesive energy was evaluated from a first-principles calculations to estimate total energy of the compounds and a vacancy formation energy, and the theory of statistical mechanics was applied to evaluate enthalpy/entropy change due to oxygen vacancies for the non-stoichiometry of the PuO 2 (i.e. PuO 2-x ). Then a vacancy-vacancy interaction energy was determined by fitting to the experimental data of a quantity of non-stoichiometry of the PuO 2 compounds as a function of oxygen potentials at large deviation from stoichiometry. The resulting Gibbs free energy yields phase boundary between the phases with good agreement with to the experimental data.

  7. Phase equilibrium of PuO{sub 2-x} - Pu{sub 2}O{sub 3} based on first-principles calculations and configurational entropy change

    Energy Technology Data Exchange (ETDEWEB)

    Minamoto, Satoshi, E-mail: satoshi.minamoto@ctc-g.co.jp [ITOCHU Techno-Solutions Corporation, Kasumigaseki, 2-5, Kasumigaseki 3-chome, Chiyoda-ku, Tokyo 100-6080 (Japan); Kato, Masato [Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki (Japan); Konashi, Kenji [Institute for Materials Research, Tohoku University, Oarai-chou, Ibaraki (Japan)

    2011-05-31

    Combination of an oxygen vacancy formation energy calculated using first-principles approach and the configurational entropy change treated within the framework of statistical mechanics gives an expression of the Gibbs free energy at large deviation from stoichiometry of plutonium oxide PuO{sub 2}. An oxygen vacancy formation energy 4.20 eV derived from our previously first-principles calculation was used to evaluate the Gibbs free energy change due to oxygen vacancies in the crystal. The oxygen partial pressures then can be evaluated from the change of the free energy with two fitting parameters (a vacancy-vacancy interaction energy and vibration entropy change due to induced vacancies). Derived thermodynamic expression for the free energy based on the SGTE thermodynamic data for the stoichiometric PuO{sub 2} and the Pu{sub 2}O{sub 3} compounds was further incorporated into the CALPHAD modeling, then phase equilibrium between the stoichiometric Pu{sub 2}O{sub 3} and non-stoichiometric PuO{sub 2-x} were reproduced.

  8. Study of phase equilibrium of Pu{sub 2}O{sub 3}-PuO{sub 2} system by the first-principles calculation and CALPHAD approach

    Energy Technology Data Exchange (ETDEWEB)

    Minamoto, Satoshi [ITOCHU Techno-Solutions Corporation, Kasumigaseki 3, Chiyoda-ku, Tokyo, Energy and Industrial Systems Department (Japan); Kato, Masato [Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki (Japan); Konashi, Kenji, E-mail: satoshi.minamoto@ctc-g.co.jp, E-mail: masato.kato@jaea.go.jp, E-mail: konashi@imr.tohoku-u.ac.jp [Institute for Materials Research, Tohoku University, Oarai-chou, Ibaraki (Japan)

    2010-03-15

    A combination of a first-principles calculation, lattice dynamics and CALPHAD (CALculation of PHAse Diagrams) modeling is proven as a powerful tool so as to evaluate the Gibbs free energy and a phase equilibrium between compounds including large amount of vacancies. In this work, non-stoichiometric PuO{sub 2-x} (dioxide) and Pu{sub 2}O{sub 3} (sesquioxide) has been studied. An electron cohesive energy was evaluated from a first-principles calculations to estimate total energy of the compounds and a vacancy formation energy, and the theory of statistical mechanics was applied to evaluate enthalpy/entropy change due to oxygen vacancies for the non-stoichiometry of the PuO{sub 2} (i.e. PuO{sub 2-x}). Then a vacancy-vacancy interaction energy was determined by fitting to the experimental data of a quantity of non-stoichiometry of the PuO{sub 2} compounds as a function of oxygen potentials at large deviation from stoichiometry. The resulting Gibbs free energy yields phase boundary between the phases with good agreement with to the experimental data.

  9. Z dependence of the N=152 deformed shell gap: In-beam γ-ray spectroscopy of neutron-rich 245,246Pu

    International Nuclear Information System (INIS)

    Makii, H.; Ishii, T.; Asai, M.; Tsukada, K.; Toyoshima, A.; Ichikawa, S.; Matsuda, M.; Makishima, A.; Kaneko, J.; Toume, H.; Shigematsu, S.; Kohno, T.; Ogawa, M.

    2007-01-01

    We have measured in-beam γ rays in the neutron-rich 246 Pu 152 and 245 Pu 151 nuclei by means of 244 Pu( 18 O, 16 O) 246 Pu and 244 Pu( 18 O, 17 O) 245 Pu neutron transfer reactions, respectively. The γ rays emitted from 246 Pu ( 245 Pu) were identified by selecting the kinetic energy of scattered 16 O ( 17 O) detected by Si ΔE-E detectors. The ground-state band of 246 Pu was established up to the 12 + state. We have found that the shell gap of N=152 is reduced in energy with decreasing atomic number by extending the systematics of the one-quasiparticle energies in N=151 nuclei into those in 245 Pu. This reduction of the shell gap clearly affects the 2 + energy of the ground-state band of 246 Pu

  10. Pu recycling in a full Th-MOX PWR core. Part I: Steady state analysis

    International Nuclear Information System (INIS)

    Fridman, E.; Kliem, S.

    2011-01-01

    Research highlights: → Detailed 3D 100% Th-MOX PWR core design is developed. → Pu incineration increased by a factor of 2 as compared to a full MOX PWR core. → The core controllability under steady state conditions is demonstrated. - Abstract: Current practice of Pu recycling in existing Light Water Reactors (LWRs) in the form of U-Pu mixed oxide fuel (MOX) is not efficient due to continuous Pu production from U-238. The use of Th-Pu mixed oxide (TOX) fuel will considerably improve Pu consumption rates because virtually no new Pu is generated from thorium. In this study, the feasibility of Pu recycling in a typical pressurized water reactor (PWR) fully loaded with TOX fuel is investigated. Detailed 3-dimensional 100% TOX and 100% MOX PWR core designs are developed. The full MOX core is considered for comparison purposes. The design stages included determination of Pu loading required to achieve 18-month fuel cycle assuming three-batch fuel management scheme, selection of poison materials, development of the core loading pattern, optimization of burnable poison loadings, evaluation of critical boron concentration requirements, estimation of reactivity coefficients, core kinetic parameters, and shutdown margin. The performance of the MOX and TOX cores under steady-state condition and during selected reactivity initiated accidents (RIAs) is compared with that of the actual uranium oxide (UOX) PWR core. Part I of this paper describes the full TOX and MOX PWR core designs and reports the results of steady state analysis. The TOX core requires a slightly higher initial Pu loading than the MOX core to achieve the target fuel cycle length. However, the TOX core exhibits superior Pu incineration capabilities. The significantly degraded worth of control materials in Pu cores is partially addressed by the use of enriched soluble boron and B 4 C as a control rod absorbing material. Wet annular burnable absorber (WABA) rods are used to flatten radial power distribution

  11. Effect of pH to adsorption behavior of Pu on bentonite in aqueous environment

    International Nuclear Information System (INIS)

    Wang Xiaoqiang; Tuo Xianguo; Li Pingchuan; Leng Yangchun; Su Jilong; Yueping

    2013-01-01

    The effects of pH to the adsorption behavior of Pu in GMZ-bentonite, Lingshou Ca-bentonite, Na-bentonite and bleaching earth were tested by static adsorption experiments in aqueous environment. The results show that the adsorption equilibrium time of Pu is four days in GMZ-bentonite and 5-6 days in bleaching earth, Ca-bentonite and Na-bentonite. In aqueous environment, the adsorption capacity of bentonite to Pu increases with pH in water phase, and it is weak in acidic aqueous environment and strong in alkaline aqueous environment extremely. (authors)

  12. Solvent extraction of Pu(IV) with TODGA in C6mimTf2N

    International Nuclear Information System (INIS)

    Xiaohong Huang; Qiuyue Zhang; Jinping Liu; Hui He; Wenbin Zhu; Xiaorong Wang

    2013-01-01

    Studies on the solvent extraction of Plutonium(Pu(IV)) from aqueous nitric acid by N,N,N'N'tetraoctyl-diglycolamide (TODGA) in 1-hexyl-3-methylimidazolium-bis(trifluoromethylsulfonyl) imide (C 6 mimTf 2 N) room temperature ionic liquid (RTIL) were carried out. It was found that Pu(IV) is extracted into RTIL phase as [Pu(NO 3 )(TODGA)] 3+ through cation exchange mechanism. Extraction reaction equation is obtained by the influence of acidity and extractant concentration, and the parameters of thermodynamic equilibrium constant was calculated. (author)

  13. Independent fission yields of Rb and Cs from thermal-neutron-induced fission of 239Pu

    International Nuclear Information System (INIS)

    Balestrini, S.J.; Forman, L.

    1975-01-01

    The relative independent fission yields of Rb and Cs from thermal-neutron-induced fission of 239 Pu have been measured on line using a mass spectrograph and thermalized neutrons from a burst reactor. Independent yields were derived by normalizing the measurements to products of chain yields and fractional independent yields, estimating the latter from measured cumulative yields of Kr and Xe. Comparing the independent yields with those from 238 U fission, the 239 Pu results show shifts in isotopic yield distribution toward lower mass for both Rb and Cs and also toward the production of more Cs and less Rb when 239 Pu is fissioned

  14. 239PU sorption by suspended matter from Hueznar reservoir (Southern Spain): experimental and modelling study

    International Nuclear Information System (INIS)

    El Mrabet, R.; Abril, J.M.; Barros, H.; Manjon, G.

    2004-01-01

    Kinetic transfer coefficients are important parameters to understand and reliably model the behaviour of non-conservative radionuclides in aquatic environments. This report pertains to a series of radiotracer experiments on 239 Pu uptake in natural unfiltered waters from the Hueznar reservoir (southern Spain). The experimental procedure ensures the preservation of environmental conditions and the dissolved Pu activity was measured by liquid scintillation technique. The data suggest that the main pathways for Pu uptake consist of two parallel and reversible reactions followed by a consecutive reversible reaction. We studied the effects of suspended matter concentrations and the specific surface area on the kinetic transfer coefficients. (author)

  15. Numerical prediction of 239Pu migration in unsaturated porous media under infiltration scenario

    International Nuclear Information System (INIS)

    Liu Dongxu; Si Gaohua; Wang Qinghai; Yu Jing

    2011-01-01

    In terms of the study on site selection of a radioactive waste disposal repository in northwest China, a numerical prediction of 239 Pu migration for potential groundwater pollution in the unsaturated zone was conducted with the HYDRUS-1D model. The results showed that the groundwater will not be contaminated by the migration of soluble 239 Pu. And there is little possibility that 239 Pu migration through groundwater path might have an unacceptable impact on exosphere. Measurements of the distribution coefficient, K d , are critical in the determination of sorption-induced retardation of radionuclide transport. (authors)

  16. Numerical prediction of 239Pu migration for groundwater pollution in the infiltration case

    International Nuclear Information System (INIS)

    Liu Dongxu; Si Gaohua; Wang Qinghai; Yu Jing

    2010-01-01

    In terms of the study on site selection of geological disposal of LIL radioactive waste in north-west China, a numerical prediction of 239 Pu migration for potential groundwater pollution in the unsaturated zone was conducted with the HYDRUS-ID model. The results showed that the groundwater will not be contaminated by the migration of soluble 239 Pu. And there is a faint possibility that 239 Pu migration through groundwater path might have an unacceptable impact on ecosphere. Measurements of the distribution coefficient, K d , are critical in the determination of sorption-induced retardation of radionuclide transport. (authors)

  17. Initial synthesis of area 13 239Pu data and other statistical analyses

    International Nuclear Information System (INIS)

    Gilbert, R.O.; Eberhardt, L.L.

    1976-02-01

    An initial effort is made here to synthesize the 239-240 Pu data currently available from Area 13 (Project 57). Plutonium concentrations for soil, vegetation, small vertebrates, and various tissues in beef cattle (grazed on the Pu contaminated vegetation) are plotted on a single graph for visual comparison. Hypothetical 239-240 Pu concentrations for lungs, skeletal bone, and kidney of a Standard Man assumed to live in and obtain most of his food from the area are also plotted. These hypothetical values were obtained using results from the plutonium transport and dose estimation model of Martin and Bloom (1975)

  18. Characterization of (241)Pu occurrence, distribution, and bioaccumulation in seabirds from northern Eurasia.

    Science.gov (United States)

    Strumińska-Parulska, Dagmara I; Skwarzec, Bogdan

    2015-05-01

    The paper presents unique data of plutonium (241)Pu study in seabirds from northern Eurasia, permanently or temporally living at the southern Baltic Sea coast. Together, ten marine birds species were examined, as follows: three species that permanently reside at the southern Baltic, four species of wintering birds, and three species of migrating birds; 366 samples were analyzed. The obtained results indicated plutonium was non-uniformly distributed in organs and tissues of analyzed seabirds. The highest (241)Pu content was found in the digestion organs and feathers, the lowest in muscles. Also, the internal radiation doses from (241)Pu were evaluated.

  19. Progress in the study on Pu chemical behavior under the geological environment

    International Nuclear Information System (INIS)

    Zhang Yingjie; Fan Xianhua

    2006-01-01

    The generation, characteristic, and disposal technology of the high level radioactive waste were discussed, and a progress in the study on the chemical behavior of Pu, a transuranic element possessing the long-term potential risk for the environment, under the geological repository was reviewed. Release behavior of Pu from the high level radioactive glass waste form, the basic chemical reactions of Pu possibly happening in groundwater, including solubility, complexation, redox reaction, and colloidal formation. Some proposals for the further work in China are also suggested. (authors)

  20. Effects of pregnancy and lactation on the toxicity of 239Pu

    International Nuclear Information System (INIS)

    Mahlum, D.D.; Hess, J.O.; Sikov, M.R.

    1980-01-01

    Nulliparous, pregnant, or lactating Wistar rats were injected intravenously with 0, 0.5 or 2.0 μCi of 239 Pu per kilogram of body weight. Half of each group were repeatedly bred while the others were held for observation without further treatment. Treatment with either dose of 239 Pu decreased the median time to appearance of mammary tumors. Repeated breeding tended to increase the mean time to appearance. Longevity was decreased in a dose-related fashion by Pu administration. Repeated breeding did not influence survival in a major way

  1. ZPR-6 assembly 7 high {sup 240} PU core : a cylindrical assemby with mixed (PU, U)-oxide fuel and a central high {sup 240} PU zone.

    Energy Technology Data Exchange (ETDEWEB)

    Lell, R. M.; Schaefer, R. W.; McKnight, R. D.; Tsiboulia, A.; Rozhikhin, Y.; Nuclear Engineering Division; Inst. of Physics and Power Engineering

    2007-10-01

    Over a period of 30 years more than a hundred Zero Power Reactor (ZPR) critical assemblies were constructed at Argonne National Laboratory. The ZPR facilities, ZPR-3, ZPR-6, ZPR-9 and ZPPR, were all fast critical assembly facilities. The ZPR critical assemblies were constructed to support fast reactor development, but data from some of these assemblies are also well suited to form the basis for criticality safety benchmarks. Of the three classes of ZPR assemblies, engineering mockups, engineering benchmarks and physics benchmarks, the last group tends to be most useful for criticality safety. Because physics benchmarks were designed to test fast reactor physics data and methods, they were as simple as possible in geometry and composition. The principal fissile species was {sup 235}U or {sup 239}Pu. Fuel enrichments ranged from 9% to 95%. Often there were only one or two main core diluent materials, such as aluminum, graphite, iron, sodium or stainless steel. The cores were reflected (and insulated from room return effects) by one or two layers of materials such as depleted uranium, lead or stainless steel. Despite their more complex nature, a small number of assemblies from the other two classes would make useful criticality safety benchmarks because they have features related to criticality safety issues, such as reflection by soil-like material. The term 'benchmark' in a ZPR program connotes a particularly simple loading aimed at gaining basic reactor physics insight, as opposed to studying a reactor design. In fact, the ZPR-6/7 Benchmark Assembly (Reference 1) had a very simple core unit cell assembled from plates of depleted uranium, sodium, iron oxide, U3O8, and plutonium. The ZPR-6/7 core cell-average composition is typical of the interior region of liquid-metal fast breeder reactors (LMFBRs) of the era. It was one part of the Demonstration Reactor Benchmark Program,a which provided integral experiments characterizing the important features of

  2. Electrochemistry and Spectroelectrochemistry of the Pu (III/IV) and (IV/VI) Couples in Nitric Acid Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lines, Amanda M. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352; Adami, Susan R. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352; Casella, Amanda J. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352; Sinkov, Sergey I. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352; Lumetta, Gregg J. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352; Bryan, Samuel A. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352

    2017-09-20

    The solution chemistry of Pu in nitric acid is explored via electrochemistry and spectroelectrochemistry. By utilizing and comparing these techniques, an improved understanding of Pu behavior and its dependence on nitric acid concentration can be achieved. Here the Pu (III/IV) couple is characterized using cyclic voltammetry, square wave voltammetry, and a spectroelectrochemical Nernst step. Results indicate the formal reduction potential of the couple shifts negative with increasing acid concentration and reversible electrochemistry is no longer attainable above 6 M HNO3. Spectroelectrochemistry is also used to explore the irreversible oxidation of Pu(IV) to Pu(VI) and shine light on the mechanism and acid dependence of the redox reaction.

  3. In vivo canine studies of a Sinkhole valve and vascular graft coated with biocompatible PU-PEO-SO3.

    Science.gov (United States)

    Han, D K; Lee, K B; Park, K D; Kim, C S; Jeong, S Y; Kim, Y H; Kim, H M; Min, B G

    1993-01-01

    PU-PEO-SO3 was applied as a coating material over a newly designed Sinkhole bileaflet PU heart valve and a porous PU vascular graft. Performance and biocompatibility were evaluated using an in vivo canine shunt system between the right ventricle and pulmonary artery. The survival periods in three implantations were 14, 24, and 39 days, during which no mechanical failure occurred in any Sinkhole valve or vascular graft. Scanning electron microscopy (SEM) studies demonstrated much less platelet adhesion and thrombus formation on PU-PEO-SO3 grafts than on PU vascular grafts. Cracks in the valve leaflet were occasionally observed on PU surfaces, but not on PU-PEO-SO3. After a 39 day implantation, calcium deposition on vascular grafts was decreased as compared with valve leaflets, and calcification on PU-PEO-SO3 was much lower than on PU. These results suggest that Sinkhole valves and vascular grafts are promising, and PU-PEO-SO3 as a coating material is more blood compatible, biostable, and calcification resistant in vivo than in untreated PU.

  4. Analytical method for the determination of Np and Pu in sea water by AMS with respect to the Fukushima accident

    Energy Technology Data Exchange (ETDEWEB)

    Hain, K., E-mail: karin.hain@mytum.de [Physics Department, Technische Universität München, James-Franck-Str.1, 85748 Garching (Germany); Faestermann, T.; Famulok, N.; Fimiani, L.; Gómez-Guzmán, J.M.; Korschinek, G. [Physics Department, Technische Universität München, James-Franck-Str.1, 85748 Garching (Germany); Kortmann, F.; Lierse von Gostomski, Ch. [Radiochemie München, Technische Universität München, Walther-Meißner-Str.3, 85748 Garching (Germany); Ludwig, P. [Physics Department, Technische Universität München, James-Franck-Str.1, 85748 Garching (Germany); Shinonaga, T. [Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Radiation Protection, Ingolstädter Landstrasse 1, 855764 Neuherberg (Germany)

    2015-10-15

    A chemical separation procedure for plutonium (Pu) and neptunium (Np) was developed using extraction chromatography, mass spectrometry and radiometric analysis to determine their concentrations and isotopic ratios in sea water. {sup 241}Am, which causes isobaric background to {sup 241}Pu in mass spectrometric measurements, was successfully separated from the Pu fraction by this method. Water samples which were spiked with {sup 242}Pu and {sup 237}Np or {sup 239}Np, respectively, were used for chemical yield determination. The chemical yields of Pu and Np, which were determined by alpha and gamma spectrometry at the Radiochemie München (RCM), of more than 85% were obtained. The developed method was applied to analyze the concentration of Pu and Np in the certified reference material, IAEA-443, by Accelerator Mass Spectrometry (AMS) at the Maier–Leibnitz-Laboratory (MLL) to check the applicability of the method to sea water samples. The concentrations of {sup 240}Pu, {sup 241}Pu and {sup 237}Np obtained in this study are in agreement with the certified and literature values within the uncertainties. Due to strong isotopic interference of {sup 239}Pu with {sup 238}U, it was not possible to analyze the concentration of {sup 239}Pu. Some modifications of the chemical separation method to suppress the uranium (U) fraction are under consideration. This method can be used for the analysis of Pu and Np in Pacific Ocean water samples collected after the Fukushima accident.

  5. Feasibility studies to assess the use of 236Pu as a radiochemical yield monitor in bioassay samples

    International Nuclear Information System (INIS)

    Sawant, P.D.; Kalsi, P.C.

    2007-01-01

    Various plutonium compounds are handled in nuclear facilities of BARC. Hence, there is a possibility of occupational workers getting exposed to Pu. In vitro bioassay monitoring in which Pu is separated by chemical procedures from excreta samples and estimated by alpha-spectrometry, is the method of choice for the evaluation of internal dose to the occupational workers handling Pu. However, this method requires a suitable Pu tracer for reducing the uncertainties due to chemical yield in the separation, electro-deposition and counting efficiency. 242 Pu is commonly used as a tracer but due to its non-availability, efforts were made earlier to indigenously synthesis 236 Pu by proton irradiation of 237 Np in BARC-TIFR pelletron facility. The present study, reports the feasibility of using 236 Pu as a radiochemical yield monitor (tracer) in bioassay samples. (author)

  6. The effects of preparation, shipment and ageing on the Pu elemental assay results of milligram-sized samples

    International Nuclear Information System (INIS)

    Berger, J.; Doubek, N.; Jammet, G.; Aigner, H.; Bagliano, G.; Donohue, D.; Kuhn, E.

    1994-02-01

    Specialized procedures have been implemented for the sampling of Pu-containing materials such as Pu nitrate, oxide or mixed oxide in States which have not yet approved type B(U) shipment containers for the air-shipment of gram-sized quantities of Pu. In such cases, it it necessary to prepare samples for shipment which contain only milligram quantities of Pu dried from solution in penicillin vials. Potential problems due to flaking-off during shipment could affect the recovery of Pu at the analytical laboratory. Therefore, a series of tests was performed with synthetic Pu nitrated, and mixed U, Pu nitrated samples to test the effectiveness of the evaporation and recovery procedures. Results of these tests as well as experience with actual inspection samples are presented, showing conclusively that the existing procedures are satisfactory. (author). 11 refs, 6 figs, 8 tabs

  7. Oxidation and reduction behaviors of a prototypic MgO-PuO{sub 2-x} inert matrix fuel

    Energy Technology Data Exchange (ETDEWEB)

    Miwa, Shuhei, E-mail: miwa.shuhei@jaea.go.jp; Osaka, Masahiko

    2017-04-15

    Oxidation and reduction behaviors of prototypic MgO-based inert matrix fuels (IMFs) containing PuO{sub 2-x} were experimentally investigated by means of thermogravimetry. The oxidation and reduction kinetics of the MgO-PuO{sub 2-x} specimen were determined. The oxidation and reduction rates of the MgO-PuO{sub 2-x} were found to be low compared with those of PuO{sub 2-x}. It is note that the changes in O/Pu ratios of MgO-PuO{sub 2-x} from stoichiometry were smaller than those of PuO{sub 2-x} at high oxygen partial pressure.

  8. Contribution to the study of the (U,Pu)C,N system; Contribution a l'etude du systeme (U,Pu)C,N

    Energy Technology Data Exchange (ETDEWEB)

    Lorenzelli, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    The reactions of UC, PuC, (U,Pu)C, UC{sub 2} and U(C{sub 1-x}O{sub x}) with nitrogen at moderate temperatures (room temperature to 400 C) are described. The influence of the uptake of nitrogen by the powders necessary to sinter the carbides upon the nature of the final product has been investigated; it has been shown that the sintered carbides are hyper-stoichiometric. The reactions of carbon with UN, PuN and (U,Pu)N has also been studied. Under vacuum, carbon reacts on the nitrides at temperatures as low as 1100 C; nitrogen is replaced by carbon and the final product is a carbonitride. The reaction is: MN + x C {yields} MN{sub 1-x}C{sub x} + x/2N{sub 2}. The reaction is limited and the carbonitrides have a fixed composition in presence of M{sub 2}C{sub 3} or MC{sub 2}; hence it is impossible to produce pure MC using the reaction. The ternary diagram U-C-N, Pu-C-N and (U,Pu)C-N have been drawn. They show clearly that it is possible to obtain single phase carbonitrides in a wide domain of compositions. (author) [French] On decrit les reactions avec l'azote de UC, PuC,(U,Pu)C,UC{sub 2} et U(C{sub 1-x}O{sub x}), par action directe de l'azote a temperature moderee (de l'ambiante a 450 C). On a etudie l'influence de la contamination par l'azote des poudres de carbures necessaires au frittage sur la nature des produits frittes; on a montre que les carbures frittes obtenus sont hyperstoechiometriques. On a etudie parallelement les reactions du carbone avec UN, PuN et (U,Pu)N. Sous vide le carbone reagit sur les nitrures des 1100 C: le carbone se substitue a l'azote; l'azote libere est elimine et le produit final est un carbonitrure. La reaction s'ecrit: MN + x C {yields} MN{sub 1-x}C{sub x} + x/2N{sub 2}. La reaction est limitee et les carbonitrures obtenus ont une composition limite fixe en presence des carbures superieurs M{sub 2}C{sub 3} et MC{sub 2}; il est donc impossible d'obtenir MC pur par cette reaction. Les diagrammes d'equilibre U-C-N, Pu-C-N et (U,Pu) C-N, ont

  9. Contribution to the study of the (U,Pu)C,N system; Contribution a l'etude du systeme (U,Pu)C,N

    Energy Technology Data Exchange (ETDEWEB)

    Lorenzelli, R. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    The reactions of UC, PuC, (U,Pu)C, UC{sub 2} and U(C{sub 1-x}O{sub x}) with nitrogen at moderate temperatures (room temperature to 400 C) are described. The influence of the uptake of nitrogen by the powders necessary to sinter the carbides upon the nature of the final product has been investigated; it has been shown that the sintered carbides are hyper-stoichiometric. The reactions of carbon with UN, PuN and (U,Pu)N has also been studied. Under vacuum, carbon reacts on the nitrides at temperatures as low as 1100 C; nitrogen is replaced by carbon and the final product is a carbonitride. The reaction is: MN + x C {yields} MN{sub 1-x}C{sub x} + x/2N{sub 2}. The reaction is limited and the carbonitrides have a fixed composition in presence of M{sub 2}C{sub 3} or MC{sub 2}; hence it is impossible to produce pure MC using the reaction. The ternary diagram U-C-N, Pu-C-N and (U,Pu)C-N have been drawn. They show clearly that it is possible to obtain single phase carbonitrides in a wide domain of compositions. (author) [French] On decrit les reactions avec l'azote de UC, PuC,(U,Pu)C,UC{sub 2} et U(C{sub 1-x}O{sub x}), par action directe de l'azote a temperature moderee (de l'ambiante a 450 C). On a etudie l'influence de la contamination par l'azote des poudres de carbures necessaires au frittage sur la nature des produits frittes; on a montre que les carbures frittes obtenus sont hyperstoechiometriques. On a etudie parallelement les reactions du carbone avec UN, PuN et (U,Pu)N. Sous vide le carbone reagit sur les nitrures des 1100 C: le carbone se substitue a l'azote; l'azote libere est elimine et le produit final est un carbonitrure. La reaction s'ecrit: MN + x C {yields} MN{sub 1-x}C{sub x} + x/2N{sub 2}. La reaction est limitee et les carbonitrures obtenus ont une composition limite fixe en presence des carbures superieurs M{sub 2}C{sub 3} et MC{sub 2}; il est donc impossible d'obtenir MC pur par cette reaction. Les diagrammes

  10. Vertical distribution of 239+240Pu-concentration and 240Pu/239Pu isotope ratio in sediment cores. Implications for the sources of plutonium in the Japan Sea

    International Nuclear Information System (INIS)

    Yamada, Masatoshi; Jian, Zheng

    2005-01-01

    The main sources in the environmental plutonium is due to nuclear explosions held during 1945 - 1980. The global fallout of plutonium is estimated to amount to 10.9 PBq, of which 6.6 PBq entering into the ocean. The Japan Sea is reported to be concentrated in plutonium in excess according to previous measurements. The present report aims to clarify the origin and transport path of plutonium in Japan Sea by measuring 240 Pu/ 239 Pu ratio in sedimenta cores with ICP-MS (Inductively Coupled Plasma Mass Spectrometry) which depends on the types of the nuclear reactor, nuclear fuels, reacting time, or the types of nuclear weapons concerned. As an example the 240 Pu/ 239 Pu ratio from the nuclear explosions in early 1960's is known to be 0.18, while that of 0.34-0.36 Bikini experiments in the Marshall Islands in early 1950's. After a detailed examination, the present authors propose that the plutonium from the explosion sites around the Marshall Islands was carried with an oceanic current to be deposited in the bed of the East-China Sea, from which a part of the plutonium was transported with the Black Stream to enter Japan Sea. (S. Ohno)

  11. Annual and life-time doses from acute and chronic intakes of 239Pu

    International Nuclear Information System (INIS)

    Bhati, Sharda; Rudran, Kamala

    1994-01-01

    A procedure to estimate annual, committed and life time doses from acute and chronic intakes of a long-lived radionuclide 239 Pu, is described. Annual dose computations, presented for 239 Pu of 5μm activity median aerodynamic diameter (AMAD), takes into account contribution from previous years intakes. Annual limits on intakes (ALI) for W and Y class of 239 Pu are computed as per the new internal dose limitation system of ICRP-61. Life time doses, corresponding to chronic intakes of 1 ALI/y for working periods of 40 and 50 years are presented for life span of 70 years of a radiation worker. These results are useful in assigning annual doses for occupational workers handling 239 Pu. (author). 5 refs., 2 tabs

  12. Late effects of 239Pu administered at representative stages of gestation

    International Nuclear Information System (INIS)

    Andrew, F.D.; Sikov, M.R.; Dagle, G.E.; Carr, D.B.

    1980-01-01

    Prenatal exposure to 239 Pu depressed offspring growth and survival rates in a relatively dose-related fashion. Histopathological evaluations of the tumors and other lesions removed at necropsy are currently underway

  13. /sup 239/Pu contamination in snakes inhabiting the Rocky Flats Plant site

    Energy Technology Data Exchange (ETDEWEB)

    Geiger, R.A.; Winsor, T.F.

    1975-01-01

    For approximately four years studies have been under way at the Rocky Flats plant to determine contamination patterns and concentrations of Pu in the biota. Contamination of the Rocky Flats environs has resulted from at least three incidents, a September 1957 fire, a May 1969 fire, and leaking barrels containing plutonium-laden cutting oil. The latter incident was considered by far the major source of the plutonium contamination. Results are reported from a study conducted to determine whether snake tissues of the area contained detectable amounts of /sup 239/Pu and, if so, at what concentrations. Eastern yellow-bellied racers (Coluber constrictor flaviventris, bullsnakes (Pituophis melanoleucus sayi, and prairie rattlesnakes (Crotalus viridis viridis, were collected for /sup 239/Pu bioassay of lung, liver, and bone tissues. Snakes were captured using drift fences terminating in funnel traps and by opportunistic sampling. Results led to the conclusion that snakes are not an important organism in the redistribution of /sup 239/Pu. (CH)

  14. Subcritical measurements with a cylindrical tank of Pu-U nitrate

    International Nuclear Information System (INIS)

    Mihalczo, J.T.; Valentine, T.E.; King, W.T.

    1997-01-01

    This series of measurements with a mixed Pu-U nitrate solution (280 g Pu/liter, 180 g U/liter) in a 35.54-cm-diam cylindrical tank provides a wide variety of experimental data for subcritical configurations that can be used to verify calculational methods and nuclear data. The Pu contained 7.85 wt% 240 Pu and the uranium was natural uranium. The measurements performed were: inverse count rate, prompt neutron decay constants, inverse kinetics, and frequency analysis by the 252 Cf source driven method. These data are presented in sufficient detail that the results of the experiments can be calculated directly. For purposes of extrapolating to the delayed critical height the ratio of spectral densities was linear with height and thus provided the best estimate of critical height

  15. Distribution of global fallout 237Np, Pu isotopes, and 241Am in lake and sea sediments

    International Nuclear Information System (INIS)

    Yamamoto, Masayoshi; Yamauchi, Y.; Chatani, K.; Komura, K.; Ueno, Kaoru; Sakanoue, Masanobu

    1991-01-01

    In order to investigate the sedimentary behaviour of neptunium, 237 Np together with Pu isotopes and 241 Am were measured for the sediment cores collected from Lake Mikata (freshwater), from Lake Kugushi (brakish water) and from Nyu Bay (sea water). In all sediment core samples 237 Np was detected, and its concentrations were far below those of 239,240 Pu and 241 Am measured for the same samples. Inventories of 237 Np in the lakes were estimated to be 0.53, 0.29 and 0.34 MBq/km 2 , respectively. The activity ratios of 237 Np/ 239,240 Pu, except for Lake Mikata, are two or three times lower than the value of 0.3-0.4% observed for surface soils of 0-20 cm depth, suggesting that Np is more soluble compared with Pu. (author) 21 refs.; 6 figs.; 3 tabs

  16. Toxicity of 239PuO2 inhaled by aged Beagle dogs. X

    International Nuclear Information System (INIS)

    Muggenburg, B.A.; Hahn, F.F.; Gillett, N.A.; Guilmette, R.A.; Boecker, B.B.; McClellan, R.O.

    1988-01-01

    The influence of age at exposure on the metabolism, dosimetry, and biological effects of inhaled 239 PuO 2 particles is being studied in aged Beagle dogs (8.0-10.5 yr of age at exposure). Forty-eight dogs inhaled 239 PuO 2 particles with an activity median aerodynamic diameter of 1.5 mm to achieve graded levels of initial pulmonary burdens (IPB) ranging from 0.02-0.66 μCi 239 Pu/kg body weight (0.75-24 kBq/kg). Twelve other dogs were exposed to the aerosol diluent only. All forty-eight exposed dogs have died, including two in the past year. The twelve control dogs have also died, including one in the past year. Radiation pneumonitis and pulmonary fibrosis have been the primary causes of death in these aged dogs exposed to 239 PuO 2 . (author)

  17. Complexation of Pu and Am with fulvic acid under saline condition

    International Nuclear Information System (INIS)

    Nagao, Seiya; Tanaka, Tadao; Ogawa, Hiromichi; Nakaguchi, Yuzuru; Suzuki, Yasuhiro; Hiraki, Keizo

    1999-01-01

    Molecular size distribution of Pu and Am in the presence of groundwater fulvic acid was studied in an ionic medium of artificial seawater by ultrafiltration technique. The 80% of Pu was mainly associated with the fulvic acid having molecular size fraction less than 5,000 daltons. The molecular size distribution of Pu was almost similar with that of fulvic acid. The results indicate that the complexation of Pu depends on the percentage of each molecular size of fulvic acid. On the other hand, 34% and 54% of Am were found in molecular size of more than 0.45 μm and less than 30,000 daltons, respectively. Am was selectively complexed with fulvic acid having molecular size of 30,000-10,000 daltons at seawater condition. (author)

  18. Magnetic susceptibility of sodium disilicate glasses containing PuO2

    International Nuclear Information System (INIS)

    Aldred, A.T.

    1979-01-01

    A solubility limit of approx. 6 mol % PuO 2 in sodium disilicate (Na 2 O.2SiO 2 ) glass has been determined. Magnetic susceptibility measurements on these glasses yield approximate Curie-Weiss behavior, in contrast to the temperature-independent susceptibility of crystalline PuO 2 . This result is interpreted to indicate that the local site symmetry around the Pu ion in the sodium disilicate glass is much different than in crystalline PuO 2 . The effective paramagnetic moments determined from the temperature dependence of the susceptibility are found to be consistent with calculated free-ion values based on the most likely 5f electron configurations

  19. First-principles elastic constants and phonons of delta-Pu

    DEFF Research Database (Denmark)

    Söderlind, P.; Landa, A.; Sadigh, B.

    2004-01-01

    Elastic constants and zone-boundary phonons of delta-plutonium have been calculated within the density-functional theory. The paramagnetic state of delta-Pu is modeled by disordered magnetism utilizing either the disordered local moment or the special quasirandom structure techniques. The anomalo......Elastic constants and zone-boundary phonons of delta-plutonium have been calculated within the density-functional theory. The paramagnetic state of delta-Pu is modeled by disordered magnetism utilizing either the disordered local moment or the special quasirandom structure techniques....... The anomalously soft C-' as well as a large anisotropy ratio (C-44/C-') of delta-Pu is reproduced by this theoretical model. Also the recently measured phonons for delta-Pu compare relatively well with their theoretical counterpart at the zone boundaries....

  20. 239Pu contamination in snakes inhabiting the Rocky Flats Plant site

    International Nuclear Information System (INIS)

    Geiger, R.A.; Winsor, T.F.

    1975-01-01

    For approximately four years studies have been under way at the Rocky Flats plant to determine contamination patterns and concentrations of Pu in the biota. Contamination of the Rocky Flats environs has resulted from at least three incidents, a September 1957 fire, a May 1969 fire, and leaking barrels containing plutonium-laden cutting oil. The latter incident was considered by far the major source of the plutonium contamination. Results are reported from a study conducted to determine whether snake tissues of the area contained detectable amounts of 239 Pu and, if so, at what concentrations. Eastern yellow-bellied racers (Coluber constrictor flaviventris, bullsnakes (Pituophis melanoleucus sayi, and prairie rattlesnakes (Crotalus viridis viridis, were collected for 239 Pu bioassay of lung, liver, and bone tissues. Snakes were captured using drift fences terminating in funnel traps and by opportunistic sampling. Results led to the conclusion that snakes are not an important organism in the redistribution of 239 Pu

  1. Combined exposure of F344 rats to beryllium metal and 239PuO2 aerosols

    International Nuclear Information System (INIS)

    Finch, G.L.; Carlton, W.W.; Rebar, A.H.; Hahn, F.F.; Hoover, M.D.; Griffith, W.C.; Mewhinney, J.A.; Cuddihy, R.G.

    1994-01-01

    Nuclear weapons industry workers have the potential for inhalation exposures to plutonium (Pu) and other agents, such as beryllium (Be) metal. Inhaled Pu deposited in the lung delivers high linear energy transfer alpha particle radiation and is known to induce pulmonary cancer in laboratory animals. Although the epidemiological evidence implicating Be in the induction of human lung cancer is weak and controversial, various studies in laboratory animals have demonstrated the pulmonary carcinogenicity of Be; Be is currently classified as a suspect human carcinogen in the United States and as a demonstrated human carcinogen by the International Agency for Research on Cancer. The purpose of this study is to investigate the potential interactions between Pu and Be in the production of lung tumors in rats exposed by inhalation to particles of plutonium dioxide ( 239 PuO 2 ), Be metal, or these agents in combination

  2. Standardization of method to determine 241Pu in urine samples by liquid scintillation analyzer

    International Nuclear Information System (INIS)

    Raveendran, Nanda; Rao, D.D.; Yadav, J.R.; Baburajan, A.

    2015-01-01

    As a part of radiation protection programme, occupational workers of fuel reprocessing plant are checked for internal contamination by analyzing urine samples periodically. Urine samples are analyzed to determine 239+240 Pu and 238 Pu by using standard conventional method and are counted by alpha spectrometry. 241 Pu is also one of the contaminant present in the urine sample of radiation workers. It is a low beta emitter with E max 21 keV. A methodology for the determination of this nuclide was standardized by using radiochemical analysis followed by Liquid Scintillation Counting. The method was tested and found suitable for the determination of 241 Pu in urine sample for the assessment of Committed Effective Dose (CED). (author)

  3. Thermal and Mechanical Properties of UO2 and PuO2

    International Nuclear Information System (INIS)

    Kato, M.; Matsumoto, T.

    2015-01-01

    It is important to evaluate basic properties of UO 2 and PuO 2 as fundamental aspects of MA-bearing MOX fuel development. In this work, mechanical properties of UO 2 and PuO 2 were investigated by an ultrasound pulse-echo method. Longitudinal and transversal wave velocities were measured in UO 2 and PuO 2 pellets, and Young's modulus and shear modulus were evaluated, which were 219 MPa and 89 MPa for PuO 2 , and 249 MPa and 95 MPa for UO 2 , respectively. Poisson's ratio was 0.32 in both materials. The relationship between mechanical and thermal properties was described by using thermal expansion data which had been reported previously, and the heat capacity and thermal conductivity were analysed. (authors)

  4. Changes in plant availability of Pu-238 during a nine year experimental period

    International Nuclear Information System (INIS)

    Eriksson, Aa.

    1985-01-01

    A short description is given of the changes observed in the plant availability of Pu-238 in eight soils during a nine year experimental period. It was found that during the first four-year period with clover as test crop, the plant uptake of Pu-238 was reduced with availability half lives ranging from 0.8 to 2.0 years. The reduction rate seemed proportional to the initial uptake levels, except for lime rich clay soils, where the reduction rate was high regardless of the uptake level. In 1980 when the test crop clover was replaced by spring wheat, the necessary soil management operations caused intenser aeration and drying in one block of the replicates. As a consequence, the Pu-uptake in that block became considerably higher than in the others. This event can be interpreted as an indirect evidence for the reversibility of that process in soil, which has caused the reduced plant availability of Pu-238

  5. Characterization and property evaluation of U–15 wt%Pu alloy for fast reactor

    International Nuclear Information System (INIS)

    Kaity, Santu; Banerjee, Joydipta; Ravi, K.; Keswani, R.; Kutty, T.R.G.; Kumar, Arun; Prasad, G.J.

    2013-01-01

    The characterization and high temperature behaviour of U–15 wt%Pu alloy has been investigated in this study for the first time. U–15 wt%Pu alloy sample for this study was prepared by following melting and casting route. Microstructural characterization of the alloy was carried out by XRD and optical microscopy. The thermophysical properties like phase transition temperatures, coefficient of thermal expansion and hot hardness of the above alloy were determined. Eutectic temperature between T91 and U–15 wt%Pu was established. Apart from that, the fuel–cladding chemical compatibility of U–15 wt%Pu alloy with T91 grade steel was studied by diffusion couple experiment

  6. Spacer for enhancing selectivity of functionalized polymer towards Pu(IV)

    International Nuclear Information System (INIS)

    Chavan, Vivek; Pandey, A.K.; Goswami, A.

    2012-01-01

    To address problems in selective and fast preconcentration of Pu(IV) at ultratrace concentration from the multicomponents aqueous media and low level nuclear waste, a new functionalized polymer sorbent was developed

  7. Differences in the initial deposition of Pu and Ra in the skeleton

    International Nuclear Information System (INIS)

    Atherton, D.R.; Bruenger, F.W.; Stevens, W.

    1978-01-01

    The ratio (still unknown) relating the experimentally determined effects of Pu and Ra in some animal species to observed effects of various isotopes of Ra in man presently provides the most reasonable basis for an assessment of the risk resulting to man from Pu. Extensive studies with the beagle have shown that an evaluation of this ratio on the basis of average skeletal radiation dose is complicated by several factors, one of which is the difference in the initial (gross) distribution of Pu and Ra between the various skeletal parts. Studies on the initial deposition of Pu and Ra in the whole skeleton and in individual parts of the skeleton after injection of the two nuclides as citrates demonstrated that significant differences in the distribution within the various skeletal parts exist, although the total deposition of the two nuclides in the whole skeleton is practically the same

  8. DFT and two-dimensional correlation analysis methods for evaluating the Pu{sup 3+}–Pu{sup 4+} electronic transition of plutonium-doped zircon

    Energy Technology Data Exchange (ETDEWEB)

    Bian, Liang, E-mail: bianliang@ms.xjb.ac.cn [Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011, Xinjiang (China); Laboratory for Extreme Conditions Matter Properties, South West University of Science and Technology, Mianyang 621010, Sichuan (China); Dong, Fa-qin; Song, Mian-xin [Laboratory for Extreme Conditions Matter Properties, South West University of Science and Technology, Mianyang 621010, Sichuan (China); Dong, Hai-liang [Department of Geology and Environmental Earth Science, Miami University, Oxford, OH 45056 (United States); Li, Wei-Min [Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011, Xinjiang (China); Duan, Tao; Xu, Jin-bao [Laboratory for Extreme Conditions Matter Properties, South West University of Science and Technology, Mianyang 621010, Sichuan (China); Zhang, Xiao-yan [Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011, Xinjiang (China); Laboratory for Extreme Conditions Matter Properties, South West University of Science and Technology, Mianyang 621010, Sichuan (China)

    2015-08-30

    Highlights: • Effect of Pu f-shell electron on the electronic property of zircon is calculated via DFT and 2D-CA techniques. • Reasons of Pu f-shell electron influencing on electronic properties are systematically discussed. • Phase transitions are found at two point 2.8 mol% and 7.5 mol%. - Abstract: Understanding how plutonium (Pu) doping affects the crystalline zircon structure is very important for risk management. However, so far, there have been only a very limited number of reports of the quantitative simulation of the effects of the Pu charge and concentration on the phase transition. In this study, we used density functional theory (DFT), virtual crystal approximation (VCA), and two-dimensional correlation analysis (2D-CA) techniques to calculate the origins of the structural and electronic transitions of Zr{sub 1−c}Pu{sub c}SiO{sub 4} over a wide range of Pu doping concentrations (c = 0–10 mol%). The calculations indicated that the low-angular-momentum Pu-f{sub xy}-shell electron excites an inner-shell O-2s{sup 2} orbital to create an oxygen defect (V{sub O-s}) below c = 2.8 mol%. This oxygen defect then captures a low-angular-momentum Zr-5p{sup 6}5s{sup 2} electron to form an sp hybrid orbital, which exhibits a stable phase structure. When c > 2.8 mol%, each accumulated V{sub O-p} defect captures a high-angular-momentum Zr-4d{sub z} electron and two Si-p{sub z} electrons to create delocalized Si{sup 4+} → Si{sup 2+} charge disproportionation. Therefore, we suggest that the optimal amount of Pu cannot exceed 7.5 mol% because of the formation of a mixture of ZrO{sub 8} polyhedral and SiO{sub 4} tetrahedral phases with the orientation (10-1). This study offers new perspective on the development of highly stable zircon-based solid solution materials.

  9. Determination of /sup 240/Pu//sup 239/Pu ratio in the environmental samples based on the measurement of Lx/. cap alpha. -ray activity ratio

    Energy Technology Data Exchange (ETDEWEB)

    Komura, K.; Sakanoue, M.; Yamamoto, M.

    1984-06-01

    The determination of the /sup 240/Pu//sup 239/Pu isotopic ratio in environmental samples has been attempted by the measurement of the Lx/..cap alpha..-ray activity ratio using a Ge-LEPS (low-energy photon spectrometer) and a surface-barrier Si detector. By this method, interesting data were obtained for various samples collected from Thule, Greenland, Bikini Atoll and Nagasaki, as well as for some soils collected from near and off-site locations of atomic power stations.

  10. Speciation analysis of 129I, 137Cs, 232Th, 238U, 239Pu and 240Pu in environmental soil and sediment

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hansen, Violeta; Hou, Xiaolin

    2012-01-01

    The environmental mobility and bioavailability of radionuclides are related to their physicochemical forms, namely species. We here present a speciation analysis of important radionuclides including 129I (also 127I), 137Cs, 232Th, 238U and plutonium isotopes (239Pu and 240Pu) in soil (IAEA-375......) and sediment (NIST-4354) standard reference materials and two fresh sediment samples from Øvre Heimdalsvatnet Lake, Norway. A modified sequential extraction protocol was used for the speciation analysis of these samples to obtain fractionation information of target radionuclides. Analytical results reveal...

  11. Fission and explosive energy releases of PuO2, PuO2--UO2, UO2, and UO3 assemblies

    International Nuclear Information System (INIS)

    Koelling, J.J.; Hansen, G.E.; Byers, C.C.

    1977-01-01

    The critical masses and fission and explosive energy releases of PuO 2 , PuO 2 --UO 2 , UO 2 , and UO 3 assemblies have been calculated. The parameters selected for the model are conservative. They were chosen after review of appropriate plants that have been and are proposed for construction in the future. The resulting data envelopes are intended to include any conceivable set of circumstances that could ultimately lead to a nuclear incident. All energy release analysis was performed for initial fission spikes only: recriticality mechanisms were not considered

  12. A study of accelerated radiation damage effects in PuO{sub 2} and gadolinia-stabilized cubic zirconia, Zr{sub 0.79}Gd{sub 0.14}Pu{sub 0.07}O{sub 1.93}, doped with {sup 238}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Burakov, B.E., E-mail: burakov@peterlink.ru [V.G. Khlopin Radium Institute, 28, 2-nd Murinskiy Ave., St. Petersburg, 194021 (Russian Federation); Yagovkina, M.A. [A.F. Ioffe Physical-Technical Institute, 26, Politekhnicheskaya, St. Petersburg, 194021 (Russian Federation)

    2015-12-15

    Polycrystalline samples of cubic zirconia, Zr{sub 0.79}Gd{sub 0.14}Pu{sub 0.07}O{sub 1.93}, doped with approximately 9.9 wt.% {sup 238}Pu, and PuO{sub 2} containing 11.0 wt. % {sup 238}Pu (and main isotope is {sup 239}Pu) have been repeatedly studied during many years by X-ray diffraction analysis. At a temperature of 25 °C the unit-cell parameter of PuO{sub 2} increases depending on accumulated dose, and is accompanied by decrease of coherent scattering region (CSR). Self-irradiation of Zr{sub 0.79}Gd{sub 0.14}Pu{sub 0.07}O{sub 1.93} is accompanied with repeated change of unit-cell parameter and CSR.

  13. Purex Process Improvements for Pu and NP Control in Total Actinide Recycle Flowsheets

    International Nuclear Information System (INIS)

    Birkett, J.E.; Carrott, M.J.; Crooks, G.; Fox, O.D.; Maher, C.J.; Taylor, R.J.; Woodhead, D.A.

    2006-01-01

    Significant improvements are required in the Purex process to optimise it for Advanced Fuel Cycles. Two key challenges we have identified are, firstly, developing more efficient methods for U/Pu separations especially at elevated Pu concentrations and, secondly, improving recovery, control and routing of Np in a modified Purex process. A series of Purex-like flowsheets for improved Pu separations based on hydroxamic acids and are reported. Purex-like flowsheets have been tested on a glovebox-housed 30-stage miniature centrifugal contactor train. A series of trials have been performed to demonstrate the processing of feeds with varying Pu contents ranging from 7 - 40% by weight. These flowsheets have demonstrated hydroxamic acids are excellent reagents for complexant stripping of Pu being able to achieve high decontamination factors (DF) on both the U and Pu product streams and co - recover Np with Pu. The advantages of a complexant-based approach are shown to be especially relevant when AFC scenarios are considered, where the Pu content of the fuel is expected to b e significantly higher. Recent results towards modifying the Purex process to improve recovery and control of Np in short residence time contactors are reported. Work on the development of chemical and process models to describe the complicated behaviour of Np under primary separation conditions (i.e. the HA extraction contactor) is described. To test the performance of the model a series of experiments were performed including testing of flowsheets on a fume-hood housed miniature centrifugal contactor train. The flowsheet was designed to emulate the conditions of a primar y separations contactor with the Np split between the U-solvent product and aqueous raffinate. In terms of Np routing the process model showed good agreement with flowsheet trial however much further work is required to fully understand this complex system. (authors)

  14. Determination of fissile fraction in MOX (mixed U + Pu oxides) fuels for different burnup values

    International Nuclear Information System (INIS)

    Ozdemir, Levent; Acar, Banu Bulut; Zabunoglu, Okan H.

    2011-01-01

    When spent Light Water Reactor fuels are processed by the standard Purex method of reprocessing, plutonium (Pu) and uranium (U) in spent fuel are obtained as pure and separate streams. The recovered Pu has a fissile content (consisting of 239 Pu and 241 Pu) greater than 60% typically (although it mainly depends on discharge burnup of spent fuel). The recovered Pu can be recycled as mixed-oxide (MOX) fuel after being blended with a fertile U makeup in a MOX fabrication plant. The burnup that can be obtained from MOX fuel depends on: (1) isotopic composition of Pu, which is closely related to the discharge burnup of spent fuel from which Pu is recovered; (2) the type of fertile U makeup material used (depleted U, natural U, or recovered U); and (3) fraction of makeup material in the mix (blending ratio), which in turn determines the total fissile fraction of MOX. Using the Non-linear Reactivity Model and the code MONTEBURNS, a step-by-step procedure for computing the total fissile content of MOX is introduced. As was intended, the resulting expression is simple enough for quick/hand calculations of total fissile content of MOX required to reach a desired burnup for a given discharge burnup of spent fuel and for a specified fertile U makeup. In any case, due to non-fissile (parasitic) content of recovered Pu, a greater fissile fraction in MOX than that in fresh U is required to obtain the same burnup as can be obtained by the fresh U fuel.

  15. European roe deer antlers as an environmental archive for fallout 236U and 239Pu

    International Nuclear Information System (INIS)

    Froehlich, M.B.; Steier, P.; Wallner, G.; Fifield, L.K.

    2016-01-01

    Anthropogenic 236 U and 239 Pu were measured in European roe deer antlers hunted between 1955 and 1977 which covers and extends beyond the period of intensive nuclear weapons testing (1954–1962). The antlers were hunting trophies, and hence the hunting area, the year of shooting and the approximate age of each animal is given. Uranium and plutonium are known to deposit in skeletal tissue. Since antler histology is similar to bone, both elements were expected in antlers. Furthermore, roe deer shed their antlers annually, and hence antlers may provide a time-resolved environmental archive for fallout radionuclides. The radiochemical procedure is based on a Pu separation step by anion exchange (Dowex 1 × 8) and a subsequent U purification by extraction chromatography using UTEVA ® . The samples were measured by Accelerator Mass Spectrometry at the VERA facility (University of Vienna). In addition to the 236 U and 239 Pu concentrations, the 240 Pu/ 239 Pu isotopic ratios were determined with a mean value of 0.172 ± 0.023 which is in agreement with the ratio of global fallout (∼0.18). Rather high 236 U/ 238 U ratios of the order of 10 −6 were observed. These measured ratios, where the 236 U arises only from global fallout, have implications for the use of the 236 U/ 238 U ratio as a fingerprint for nuclear accidents or releases from nuclear facilities. Our investigations have shown the potential to use antlers as a temporally resolved archive for the uptake of actinides from the environment. - Highlights: • Roe deer antlers were studied as an environmental archive for the retrospective study of fallout isotopes 236 U and 239 Pu. • The rather high 236 U/ 238 U ratios of about 10 −6 suggest 236 U as a fingerprint tool for nuclear material releases. • The 240 Pu/ 239 Pu atom ratio underpins global fallout as the main anthropogenic contributor in antlers.

  16. Pu Sorption, Desorption and Intrinsic Colloid Stability under Granitic Chemical Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Pihong [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zavarin, Mavrik [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dai, Zurong [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kersting, Annie B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-09-04

    This progress report (M4FT-14LL0807031) describes research conducted at LLNL as part of the Crystalline Repository effort within the UFD program. Part I describes the dissolution kinetics of intrinsic Pu colloids synthesized in an alkaline solution. Part II describes the morphology and dissolution characteristics of various forms of Pu oxides prepared over a range of solution and temperature conditions. Proposed FY15 activities are identified.

  17. Fully automated system for Pu measurement by gamma spectrometry of alpha contaminated solid wastes

    International Nuclear Information System (INIS)

    Cresti, P.

    1986-01-01

    A description is given of a fully automated system developed at Comb/Mepis Laboratories which is based on the detection of specific gamma signatures of Pu isotopes for monitoring Pu content in 15-25 l containers of low density (0.1 g/cm 3 ) wastes. The methodological approach is discussed; based on experimental data, an evaluation of the achievable performances (detection limit, precision, accuracy, etc.) is also given

  18. Transcriptional factor PU.1 regulates decidual C1q expression in early pregnancy in human

    Directory of Open Access Journals (Sweden)

    Priyaa Madhukaran Raj

    2015-02-01

    Full Text Available C1q is the first recognition subcomponent of the complement classical pathway, which in addition to being synthesized in the liver, is also expressed by macrophages and dendritic cells. Trophoblast invasion during early placentation results in accumulation of debris that triggers the complement system. Hence, both early and late components of the classical pathway are widely distributed in the placenta and decidua. In addition, C1q has recently been shown to significantly contribute to feto-maternal tolerance, trophoblast migration, and spiral artery remodeling, although the exact mechanism remains unknown. Pregnancy in mice, genetically deficient in C1q, mirrors symptoms similar to that of human preeclampsia. Thus, regulated complement activation has been proposed as an essential requirement for normal successful pregnancy. Little is known about the molecular pathways that regulate C1q expression in pregnancy. PU.1, an Ets-family transcription factor, is required for the development of hematopoietic myeloid lineage immune cells, and its expression is tissue- specific. Recently, PU.1 has been shown to regulate C1q gene expression in dendritic cells and macrophages. Here, we have examined if PU.1 transcription factor regulates decidual C1q expression. We used immune-histochemical analysis, PCR and immunostaining to localize and study the gene expression of PU.1 transcription factor in early human decidua. PU.1 was highly expressed at gene and protein level in early human decidual cells including trophoblast and stromal cells. Surprisingly, nuclear as well as cytoplasmic PU.1 expression was observed. Decidual cells with predominantly nuclear PU.1 expression had higher C1q expression. It is likely that nuclear and cytoplasmic PU.1 localization has a role to play in early pregnancy via regulating C1q expression in the decidua during implantation.

  19. Ecological studies of small vertebrates in Pu-contaminated study areas of NTS and TTR

    International Nuclear Information System (INIS)

    Bradley, W.G.; Moor, K.S.

    1975-01-01

    Ecological studies of vertebrates in plutonium-contaminated areas of the Nevada Test Site (NTS) were initiated in March 1972, and have continued to date. In September 1973, standard census methods were also employed to derive a qualitative and quantitative inventory of vertebrate biota of four Nevada Applied Ecology Group (NAEG) study areas of the Tonopah Test Range (TTR). A checklist of vertebrates of NAEG study areas of NTS and TTR is presented. Data are presented on vertebrate composition, relative abundance, and seasonal status in the study areas. Concentrations of 239 Pu and 241 Am were determined in pelt or skin, GI tract, and carcass of 13 lizards and 16 mammals resident on Clean Slate 2, TTR, and Area 11, NTS. A total of 71 animals were collected for radioanalysis. However, the data were not available at the time this report was written. Pu tissue burdens were highest in lizards from Area 11 GZ. Maximum values obtained in nCi/g ash were 30.9, 42.2, and 0.43 for the pelt, GI tract, and carcass, respectively. Maximum 239 Pu values in tissues of small rodents from Area 11 (not from GZ) were 11.4, 6.49, and 0.20 nCi/g ash for pelt, GI tract, and carcass, respectively. Pu/Am ratios were relatively consistent in tissue samples of lizards and small mammals from Area 11 (approximately 6:1, Pu/Am). Pu/Am ratios were not consistent in vertebrates of Clean Slate 2, TTR, and appeared to be lower in carcass (28:1, Pu/Am in mammals) than GI tract (9:1, Pu/Am in mammals). Although this trend was more conspicuous in mammals, it was also evident in reptiles. (auth)

  20. Thermal conductivities of (ZrxPu(1-x)/2Am(1-x)/2)N solid solutions

    International Nuclear Information System (INIS)

    Nishi, Tsuyoshi; Takano, Masahide; Akabori, Mitsuo; Arai, Yasuo

    2011-01-01

    The thermal conductivity of Zr-based transuranium (TRU) nitride solid solutions is important for designing subcritical cores in nitride-fueled ADS. Some results have been reported concerning the thermal conductivities of (Zr,Pu)N. However, there have been no experimental data on the thermal conductivities of Zr-based nitride solid solutions containing MA. In this study, the authors prepared sintered samples of (Zr x Pu (1-x)/2 Am (1-x)/2) N (x=0.0, 0.58, 0.80) solid solutions. The thermal diffusivity and heat capacity of (Zr x Pu (1-x)/2 Am (1-x)/2) N solid solutions were measured using a laser flash method and drop calorimetry, respectively. Thermal conductivities were determined from the measured thermal diffusivities, heat capacities and bulk densities over a temperature range of 473 to 1473 K. The thermal conductivities of (Zr 0.58 Pu 0.21 Am 0.21 )N and (Zr 0.80 Pu 0.10 Am 0.10 )N solid solutions were found to be higher than that of (Pu 0.5 Am 0.5 )N due to the high thermal conductivity of ZrN as the principal component, although they were lower than that of ZrN due to the impurifying effect of the transuranium elements. Thus, the thermal conductivities of (Zr x Pu (1-x)/2 Am (1-x)/2) N solid solutions increased with increasing ZrN concentration. Moreover, in order to help to promote the design study of nitride-fueled ADS, the thermal conductivity of the (Zr x Pu (1-x)/2 Am (1-x)/2) N solid solutions were fitted to an equation using the least squares method. (author)

  1. Structure and phase stability of a Pu-0.32 wt% Ga alloy

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, D.W., E-mail: David.Wheeler@awe.co.uk; Ennaceur, S.M.; Matthews, M.B.; Roussel, P.; Bayer, P.D.

    2016-08-01

    In plutonium-gallium (Pu-Ga) alloys that have a Ga content of 0.3–0.4 wt%, their readiness to transform to α′ renders them of particular interest in efforts to understand the tenuous nature of δ phase stability. The present study is a comprehensive examination of the structure and phase stability of a cast Pu-0.32 wt% Ga alloy, the Ga content being close to the minimum amount needed to retain the δ phase to ambient temperature. The alloy was characterised in both the as-cast condition as well as following a homogenising heat treatment. The 250-h heat treatment at 450 °C was shown to achieve an apparently stable δ-Pu phase. However, the stability of the δ-Pu phase was shown to be marginal: partial transformation to α′-Pu was observed when the alloy was subjected to hydrostatic compression. Similar transformation was also apparent during metallographic preparation as well as during hardness indentation. The results provide new understanding of the nature of δ phase stability. - Highlights: • New insights into the delta phase stability of a Pu-0.32 wt% Ga alloy. • Density and DSC of as-cast alloy both show α-Pu contents of approximately 30%. • The heat-treated alloy has a largely δ-Pu structure at ambient temperature. • Heat-treated alloy susceptible to δ → α transformation during hardness indentation.

  2. Migration of 90Sr, 137Cs and Pu in soils. Verification of a computer model on the behaviour of these radiocontaminants in soils of Western Europe

    International Nuclear Information System (INIS)

    Frissel, M.J.; Poelstra, P.; Klugt, N. van der.

    1980-01-01

    The main emphasis in 1979 was on the 239 240 Pu model for simulating translocations in soil. The verification was hampered because data for 239 Pu were available from only two locations. A comparison between the observed and predicted Pu distribution however indicated the possibility of using the available simulation approach for 239 240 Pu. (Auth.)

  3. Determination of Pu isotopic composition and 241Am by high resolution gamma spectrometry on solid samples

    International Nuclear Information System (INIS)

    Sarkar, Arnab; Paul, Sumana; Aggarwal, Suresh K.; Tomar, Bhupendra S.

    2011-08-01

    The present report gives a detailed account of the development of non-destructive assay technique using high resolution gamma-ray spectrometry (HRGS) for determination of plutonium (Pu) isotopic composition and the 241 Am content in solid Pu samples. Energy range 120-420 keV was used in this study. The methodology involves in situ relative efficiency calibration during the measurement process itself, to reduce the errors and increase the reliability of the method. Twenty solid Pu samples of power reactor and research reactor grade were analyzed by this method and the results were compared with those obtained by thermal ionization mass spectrometry. The accuracy of the final results depends strongly upon the accuracy of the available nuclear data (decay constant, gamma abundance etc.). MATLAB based programme was written to perform the analysis. A counting time of 4 hour was chosen for achieving good statistics on the results for samples having 100-200 mg of Pu. The attainable accuracy is found to be 0.5-1% for the fissile isotopes ( 239 Pu + 241 Pu) and 5-10% for 241 Am content. (author)

  4. Characterization and testing of a 238Pu loaded ceramic waste form

    International Nuclear Information System (INIS)

    Johnson, S. G.

    1998-01-01

    This paper will describe the preparation and progress of the effort at Argonne National Laboratory-West to produce ceramic waste forms loaded with 238 Pu. The purpose of this study is to determine the extent of damage, if any, that alpha decay events will play over time to the ceramic waste form under development at Argonne. The ceramic waste form is glass-bonded sodalite. The sodalite is utilized to encapsulate the fission products and transuranics which are present in a chloride salt matrix which results from a spent fuel conditioning process. 238 Pu possesses approximately 250 times the specific activity of 239 Pu and thus allows for a much shorter time frame to address the issue. In preparation for production of 238 Pu loaded waste forms 239 Pu loaded samples were produced. Data is presented for samples produced with typical reactor grade plutonium. X-ray diffraction, scanning electron micrographs and durability test results will be presented. The ramifications for the production of the 238 Pu loaded samples will be discussed

  5. 238Pu concentrations in the marine environment at San Clemente Island

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Brunk, J.L.; Jokela, T.A.; Wong, K.M.

    1981-01-01

    The concentration of plutonium and other radionuclides measured in samples of surface sediments, seawater and brown algae collected offshore from North Light Harbor Pier at San Clemente Island, CA, are presented. From 1967 to 1978, different forms of nuclear fuels used in operational or proposed SNAP (Systems for Nuclear Auxillary Power) devices were tested at this site to evaluate the effects of seawater on the heat sources. The principle radionuclide in the heat sources tested was 238 Pu. During these tests, small amounts of 238 Pu dissolved and migrated from the test chambers to the local marine environment. Currents dispersed this released 238 Pu so that at present a small increase in concentration above that of fallout background is evident in the surface 3.0-cm layer of near shore sediment that extends over a 3.0-km 2 area surrounding the pier. The 238 Pu associated with this sediment is slowly redissolving and can be taken up by marine algae. Except for a 0.025-km 2 region around the pier, the total plutonium ( 238 Pu + 239+240 Pu) in the surface 3.0-cm layer of sediment is within the range of total fallout plutonium reported in Atlantic and Pacific surface deposits from water depths less than 100 m. (author)

  6. A rapid method for estimation of Pu-isotopes in urine samples using high volume centrifuge.

    Science.gov (United States)

    Kumar, Ranjeet; Rao, D D; Dubla, Rupali; Yadav, J R

    2017-07-01

    The conventional radio-analytical technique used for estimation of Pu-isotopes in urine samples involves anion exchange/TEVA column separation followed by alpha spectrometry. This sequence of analysis consumes nearly 3-4 days for completion. Many a times excreta analysis results are required urgently, particularly under repeat and incidental/emergency situations. Therefore, there is need to reduce the analysis time for the estimation of Pu-isotopes in bioassay samples. This paper gives the details of standardization of a rapid method for estimation of Pu-isotopes in urine samples using multi-purpose centrifuge, TEVA resin followed by alpha spectrometry. The rapid method involves oxidation of urine samples, co-precipitation of plutonium along with calcium phosphate followed by sample preparation using high volume centrifuge and separation of Pu using TEVA resin. Pu-fraction was electrodeposited and activity estimated using 236 Pu tracer recovery by alpha spectrometry. Ten routine urine samples of radiation workers were analyzed and consistent radiochemical tracer recovery was obtained in the range 47-88% with a mean and standard deviation of 64.4% and 11.3% respectively. With this newly standardized technique, the whole analytical procedure is completed within 9h (one working day hour). Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Non-destructive assay of 242Pu by resonance neutron capture

    International Nuclear Information System (INIS)

    Kane, W.R.; Lu, Ming-Shih; Aronson, A.; Forman, L.; Vanier, P.E.

    1995-01-01

    For the accurate assay of plutonium by neutron correlation measurements, especially for material derived from high-burnup reactor fuel, the content of 242 Pu in a sample must be determined. Since 242 Pu has a long half-life (387,000 yr) and decays to 238 U by alpha particle emission with the accompanying emission of only weak, low-energy gamma rays, gamma-ray spectrometry methods which are ordinarily employed to determine the isotopic composition of a plutonium sample are not feasible for 242 Pu. The existence of a resonance in the neutron capture cross section of 242 Pu at an energy of 2.67 electron volts (eV) with a large (72, 000 barn) cross section affords the possibility for the quantitative assay of this isotope by epithermal neutron capture. Essential for this purpose is an appropriately designed geometry of neutron moderators and absorbers which will provide maximum flux in the eV region while suppressing thermal neutron capture by the fissile plutonium isotopes. Signatures for neutron capture in 242 Pu include the decay of 243 Pu (4.9 hr), prompt capture gamma rays (total energy 5.034 MeV), and the decay of an isomeric state (330 nanosecond). Experiments to determine the feasibility of this approach are currently in progress

  8. Contribution to the study of the (U,Pu)C,N system

    International Nuclear Information System (INIS)

    Lorenzelli, R.

    1968-01-01

    The reactions of UC, PuC, (U,Pu)C, UC 2 and U(C 1-x O x ) with nitrogen at moderate temperatures (room temperature to 400 C) are described. The influence of the uptake of nitrogen by the powders necessary to sinter the carbides upon the nature of the final product has been investigated; it has been shown that the sintered carbides are hyper-stoichiometric. The reactions of carbon with UN, PuN and (U,Pu)N has also been studied. Under vacuum, carbon reacts on the nitrides at temperatures as low as 1100 C; nitrogen is replaced by carbon and the final product is a carbonitride. The reaction is: MN + x C → MN 1-x C x + x/2N 2 . The reaction is limited and the carbonitrides have a fixed composition in presence of M 2 C 3 or MC 2 ; hence it is impossible to produce pure MC using the reaction. The ternary diagram U-C-N, Pu-C-N and (U,Pu)C-N have been drawn. They show clearly that it is possible to obtain single phase carbonitrides in a wide domain of compositions. (author) [fr

  9. Magnetic order in Pu2M3Si5 (M = Co, Ni)

    International Nuclear Information System (INIS)

    Bauer, E D; Tobash, P H; Mitchell, J N; Kennison, J A; Ronning, F; Scott, B L; Thompson, J D

    2011-01-01

    The physical properties including magnetic susceptibility, specific heat, and electrical resistivity of two new plutonium compounds Pu 2 M 3 Si 5 (M = Co, Ni) are reported. Pu 2 Ni 3 Si 5 crystallizes in the orthorhombic U 2 Co 3 Si 5 structure type, which can be considered a variant of the BaAl 4 tetragonal structure, while Pu 2 Co 3 Si 5 adopts the closely related monoclinic Lu 2 Co 3 Si 5 type. Magnetic order is observed in both compounds, with Pu 2 Ni 3 Si 5 ordering ferromagnetically at T C = 65 K then undergoing a transition into an antiferromagnetic state below T N = 35 K. Two successive magnetic transitions are also observed at T mag1 = 38 K and T mag2 = 5 K in Pu 2 Co 3 Si 5 . Specific heat measurements reveal that these two materials have a moderately enhanced Sommerfeld coefficient γ ∼ 100 mJ/mol Pu K 2 in the magnetic state with comparable RKKY and Kondo energy scales.

  10. A proposed new mission for producing 238Pu at the Hanford site

    International Nuclear Information System (INIS)

    Cash, R.J.

    1989-01-01

    A new mission for producing 238 Pu has been proposed at the Hanford site. If approved, the program would produce 238 Pu for National Aeronautics and Space Administration (NASA) space missions and possibly other speciality isotopes for medical and industrial applications. The 238 Pu isotope is an excellent heat source and is currently used in generating electricity for deep-space applications. To produce 238 Pu, special neptunium target assemblies would be irradiated for ∼2 yr in the Fast Flux Test Facility (FFTF) operated by Westinghouse Handford Company. After ∼1 yr of cooling, the neptunium pins would be reprocessed in special hot cells in the Fuel and Materials Examination Facility (FMEF) at the Hanford site to recover the 238 Pu and convert it into the oxide form. The oxide could then be encapsulated in the FMEF using special materials and procedures to meet rigid NASA requirements. The plutonium oxide capsules would later become part of the radioisotope thermoelectric generators used by NASA to power equipment launched into space. To meet projected NASA mission requirements, the program would provide the capability to recover up to 30 kg/yr of 238 Pu from 237 Np targets by late 1993. The conceptual design for the program was completed by Westinghouse Hanford in September 1989 for validation and approval by the U.S. Department of Energy

  11. Could weapon-grade plutonium be an asset for managing Pu inventories?

    International Nuclear Information System (INIS)

    Bairiot, H.; Bemden, E. van den

    1997-01-01

    Due to the temporary shortage of MOX fuel fabrication facilities, the stockpile of separated civilian grade Pu (CPu) is predicted to increase up to the turn of the century. An additional quantity of weapon grade Pu (WPu) will be progressively isolated at the same period. Both CPu and WPu surpluses require disposition as soon as feasible. Although non-proliferation concerns, established national policies, public acceptance problems and other considerations largely complicate the aspect of the use of WPu, it is worth examining the advantages which could result from a synergetic management of: LWR grade Pu to which AGR grade Pu might be associated; WPu; GCR grade Pu which should be considered as a Pu variety situated between the two first ones as far as their physical and neutronic characteristics are concerned. Two scenarios of integrated managements of the CPu varieties and WPu are being considered. They indicate several technical and economical advantages but also important problems to be resolved, mainly from the non-proliferation point of view. In that respect, it is concluded that, although no reasonable perspective exists to resolve these problems easily (or at all), the advantages justify an effort of the international community to consider how it could be implemented. (author). 24 refs, 2 figs, 5 tabs

  12. Conversion electron spectrometry of Pu isotopes with a silicon drift detector.

    Science.gov (United States)

    Pommé, S; Paepen, J; Peräjärvi, K; Turunen, J; Pöllänen, R

    2016-03-01

    An electron spectrometry set-up was built at IRMM consisting of a vacuum chamber with a moveable source holder and windowless Peltier-cooled silicon drift detector (SDD). The SDD is well suited for measuring low-energy x rays and electrons emitted from thin radioactive sources with low self-absorption. The attainable energy resolution is better than 0.5keV for electrons of 30keV. It has been used to measure the conversion electron spectra of three plutonium isotopes, i.e. (238)Pu, (239)Pu, (240)Pu, as well as (241)Am (being a decay product of (241)Pu). The obtained mixed x-ray and electron spectra are compared with spectra obtained with a close-geometry set-up using another SDD in STUK and spectra measured with a Si(Li) detector at IRMM. The potential of conversion electron spectrometry for isotopic analysis of mixed plutonium samples is investigated. With respect to the (240)Pu/(239)Pu isotopic ratio, the conversion electron peaks of both isotopes are more clearly separated than their largely overlapping peaks in alpha spectra. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Measurement of the ${240}$Pu(n,f) reaction cross-section

    CERN Multimedia

    Following proposal CERN-INTC-2010-042 / INTC-P-280 (“Measurement of the fission cross-section of $^{240}$Pu and $^{242}$Pu at CERN’s n_TOF Facility”), the parallel measurement of the $^{240}$Pu(n,f) and $^{242}$Pu(n,f) reaction cross-sections was carried out at n_TOF EAR-1. While the $^{242}$Pu measurement was successful, unexpected sample-induced damage to the detectors caused by the high α-activity of the 240Pu samples resulted in a deterioration of the detector performance over the data taking period of several months, which compromised the measurement. This obstacle can be eliminated by performing the measurement in EAR-2, where the higher neutron flux will allow collecting data in a much shorter time, thus preventing the degradation of the detectors. In addition to this obvious advantage, the measurement would also benefit from the stronger suppression of the sample-induced α-background, due to the shorter times-of-flight involved.

  14. Chromosome aberration frequency in blood lymphocytes of animals with 239Pu lung burdens

    International Nuclear Information System (INIS)

    Brooks, A.L.; LaBauve, R.J.; McClellan, R.O.; Jensen, D.A.

    1976-01-01

    Other investigators have suggested a causal relationship between accidental 239 Pu exposures in man and the presence of chromosome aberrations in blood lymphocytes. For experimental assessment of this relationship, 16 rhesus monkeys and 171 Chinese hamsters were exposed to 239 PuO 2 aerosols and an additional five hamsters were injected with 239 Pu citrate, and the frequency of aberrations in blood lymphocyte was determined. Hamsters with the highest lung burden had a median survival time of about 80 days. No deaths occurred in any of the other treated hamsters or monkeys by 250 days after 239 Pu inhalation. Hamsters sacrificed at 30 days showed an increase in chromosome aberration frequency with increasing dose to lungs. By 120 days after inhalation, the aberration frequency in the controls was 0.012. The frequency in animals with doses that produced significant life shortening had decreased to 0.018 and to 0.032 aberration/cell in animals with lower doses. At 380 days after injection of 2 nCi of 239 Pu citrate per gram of body weight, hamster lymphocytes had an aberration frequency of 0.048 aberration/cell. The level of chromosome damage in the 239 PuO 2 -exposed monkeys at 30 and 90 days after inhalation was not different from that observed in controls. Possible reasons for differences between the experimental animal observations and findings in man are discussed

  15. A theoretical study of hydrogen atoms adsorption and diffusion on PuO_2 (110) surface

    International Nuclear Information System (INIS)

    Yu, H.L.; Tang, T.; Zheng, S.T.; Shi, Y.; Qiu, R.Z.; Luo, W.H.; Meng, D.Q.

    2016-01-01

    The mechanisms of adsorption and diffusion of hydrogen atoms on the PuO_2 (110) surface are investigated by density functional theory corrected for onsite Coulombic interactions (GGA + U). In order to find out the energetically more favorable adsorption site and optimum diffusion path, adsorption energy of atomic H on various sites and the diffusion energy barrier are derived and compared. Our results show that both chemisorption and physisorption exist for H atoms adsorption configurations on PuO_2 (110) surface. Two processes for H diffusion are investigated using the climbing nudged-elastic-band (cNEB) approach. We have identified two diffusion mechanisms, leading to migration of atomic H on the surface and diffusion from surface to subsurface. The energy barriers indicate that it is energetically more favorable for H atom to be on the surface. Hydrogen permeation through purity PuO_2 surface is mainly inhibited from hydrogen atom diffusion from surface to subsurface. - Highlights: • H atoms adsorption on PuO_2 (110) surface are investigated by GGA + U. • Both chemisorption and physisorption exist for H atoms adsorption configurations. • H atoms migration into PuO_2 (100) surface are inhibited with the barrier of 2.15 eV. • H atoms diffusion on PuO_2 (110) surface are difficult at room temperature.

  16. Effects of Pu-erh ripened tea on hyperuricemic mice studied by serum metabolomics.

    Science.gov (United States)

    Zhao, Ran; Chen, Dong; Wu, Hualing

    2017-11-15

    To evaluate effects of Pu-erh ripened tea in hyperuricemic mice, a mouse hyperuricemia model was developed by oral administration of potassium oxonate for 7 d. Serum metabolomics, based on gas chromatography-mass spectrometry, was used to generate metabolic profiles from normal control, hyperuricemic and allopurinol-treated hyperuricemic mice, as well as hyperuricemic mice given Pu-erh ripened tea at three doses. Pu-erh ripened tea significantly lowered serum uric acid levels. Twelve potential biomarkers associated with hyperuricemia were identified. Pu-erh ripened tea and allopurinol differed in their metabolic effects in the hyperuricemic mice. Levels of glutamic acid, indolelactate, L-allothreonine, nicotinoylglycine, isoleucine, l-cysteine and glycocyamine, all involved in amino acid metabolism, were significantly changed in hyperuricemic mice treated Pu-erh ripened tea. Thus, modulating amino acid metabolism might be the primary mechanism of anti-hyperuricemia by Pu-erh ripened tea. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Determination of 240Pu/239Pu isotopic ratios in human tissues collected from areas around the Semipalatinsk Nuclear Test Site by sector-field high resolution ICP-MS.

    Science.gov (United States)

    Yamamoto, M; Oikawa, S; Sakaguchi, A; Tomita, J; Hoshi, M; Apsalikov, K N

    2008-09-01

    Information on the 240Pu/239Pu isotope ratios in human tissues for people living around the Semipalatinsk Nuclear Test Site (SNTS) was deduced from 9 sets of soft tissues and bones, and 23 other bone samples obtained by autopsy. Plutonium was radiochemically separated and purified, and plutonium isotopes (239Pu and 240Pu) were determined by sector-field high resolution inductively coupled plasma-mass spectrometry. For most of the tissue samples from the former nine subjects, low 240Pu/239Pu isotope ratios were determined: bone, 0.125 +/- 0.018 (0.113-0.145, n = 4); lungs, 0.063 +/- 0.010 (0.051-0.078, n = 5); and liver, 0.148 +/- 0.026 (0.104-0.189, n = 9). Only 239Pu was detected in the kidney samples; the amount of 240Pu was too small to be measured, probably due to the small size of samples analyzed. The mean 240Pu/239Pu isotope ratio for bone samples from the latter 23 subjects was 0.152 +/- 0.034, ranging from 0.088 to 0.207. A significant difference (a two-tailed Student's t test; 95% significant level, alpha = 0.05) between mean 240Pu/239Pu isotope ratios for the tissue samples and for the global fallout value (0.178 +/- 0.014) indicated that weapons-grade plutonium from the atomic bombs has been incorporated into the human tissues, especially lungs, in the residents living around the SNTS. The present 239,240Pu concentrations in bone, lung, and liver samples were, however, not much different from ranges found for human tissues from other countries that were due solely to global fallout during the 1970's-1980's.

  18. Comparative analysis of Pu spread resistance of chemico-technological (out of pile) complexes of electronuclear molten salt and heavy water blanket facilities for transmutation

    International Nuclear Information System (INIS)

    Volk, V.I.; Vakhrushin, A.Yu.; Gorbunov, V.F.; Kushnikov, V.V.

    1997-01-01

    Technological processes used for radiochemical reprocessing of molten salt and heavy water blankets of an electronuclear facility for Pu transmutation and Pu distribution in those processes are characterized. Below the major parameters are given that affect the resistance of the technological to Pu proliferation. Types of Pu migration: process losses, accident related losses, theft. Factors affecting migration are total inventory of Pu in a reprocessing complex, purity of Pu and its compounds, chemical condition of Pu, the feasibility of equipping technological processes with instruments of control. The comparative analysis carried out taking into account the above parameters established that the technological processes related to heavy water blanket reprocessing, specifically a homogeneous (solution) option, are much more resistant to Pu proliferation, including both Pu migration to the environment and the unsanctioned withdrawal of Pu from the technological process. 5 refs., 4 figs

  19. Pu isotopes in the western North Pacific Ocean before the accident at Fukushima Dai-ichi Nuclear Power Station

    Science.gov (United States)

    Yamada, M.; Zheng, J.; Aono, T.

    2011-12-01

    Anthropogenic radionuclides such as Pu-239 (half-life: 24100 yr), Pu-240 (half-life: 6560 yr) and Pu-241 (half-life: 14.325 yr) mainly have been released into the environment as the result of atmospheric nuclear weapons testing. In the North Pacific Ocean, two distinct sources of Pu isotopes can be identified; i.e., the global stratospheric fallout and close-in tropospheric fallout from nuclear weapons testing at the Pacific Proving Grounds in the Marshall Islands. The atom ratio of Pu-240/Pu-239 is a powerful fingerprint to identify the sources of Pu in the ocean. The Pu-240/Pu-239 atom ratios in seawater and marine sediment samples collected in the western North Pacific before the accident at Fukushima Dai-ichi Nuclear Power Station will provide useful background data for understanding the process controlling Pu transport and for distinguishing future Pu sources. The atom ratios of Pu-240/Pu-239 in water columns from the Yamato and Tsushima Basins in the Japan Sea were significantly higher than the mean global fallout ratio of 0.18; however, there were no temporal variation of atom ratios during the period from 1984 to 1993 in the Japan Sea. The total Pu-239+240 inventories in the whole water columns were approximately doubled during the period from 1984 to 1993 in the two basins. The atom ratio of Pu-240/Pu-239 in surface water from Sagami Bay, western North Pacific Ocean, was 0.224 and showed no notable variation from the surface to the bottom with the mean atom ratio being 0.234. The atom ratios for the Pacific coast, near the Rokkasho nuclear fuel reprocessing plant, were approximately the same as the 0.224 ratio obtained from Sagami Bay, western North Pacific margin. The atom ratios in the surficial sediments from Sagami Bay ranged from 0.229 to 0.247. The mean atom ratio in the sediment columns in the East China Sea ranged from 0.248 for the Changjiang estuary to 0.268 for the shelf edge. The observed atom ratios were significantly higher than the mean

  20. Gamma densitometer for measuring Pu density in fuel tubes

    International Nuclear Information System (INIS)

    Winn, W.G.

    1982-01-01

    A fuel-gamma-densitometer (FGD) has been developed to examine nondestructively the uniformity of plutonium in aluminum-clad fuel tubes at the Savannah River Plant (SRP). The monitoring technique is γ-ray spectroscopy with a lead-collimated Ge(Li) detector. Plutonium density is correlated with the measured intensity of the 208 keV γ-ray from 237 U (7d) of the 241 Pu (15y) decay chain. The FGD measures the plutonium density within 0.125- or 0.25-inch-diameter areas of the 0.133- to 0.183-inch-thick tube walls. Each measurement yields a density ratio that relates the plutonium density of the measured area to the plutonium density in normal regions of the tube. The technique was used to appraise a series of fuel tubes to be irradated in an SRP reactor. High-density plutonium areas were initially identified by x-ray methods and then examined quantitatively with the FGD. The FGD reliably tested fuel tubes and yielded density ratios over a range of 0.0 to 2.5. FGD measurements examined (1) nonuniform plutonium densities or hot spots, (2) uniform high-density patches, and (3) plutonium density distribution in thin cladding regions. Measurements for tubes with known plutonium density agreed with predictions to within 2%. Attenuation measurements of the 208-keV γ-ray passage through the tube walls agreed to within 2 to 3% of calculated predictions. Collimator leakage measurements agreed with model calculations that predicted less than a 1.5% effect on plutonium density ratios. Finally, FGD measurements correlated well with x-ray transmission and fluoroscopic measurements. The data analysis for density ratios involved a small correction of about 10% for γ-shielding within the fuel tube. For hot spot examinations, limited information for this correction dictated a density ratio uncertainty of 3 to 5%

  1. Pu distribution in seawater in the near coastal area off Fukushima after the Fukushima Daiichi Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    Bu, W.T.; Zheng, J.; Aono, T.; Wu, J.W.; Tagami, K.; Uchida, S.; Guo, Q.J.; Yamada, M.

    2015-01-01

    The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident released large amount of radionuclides into the marine environment. Compared with the fission products, data on the distributions of Pu in the marine environment of the western North Pacific after the accident is limited. To better understand the Pu contamination in the marine environment after the accident, for the first time, we determined Pu isotope ratio ( 240 Pu/ 239 Pu) in addition to 239+240 Pu activity in seawater collected in the near coastal area (mostly within the 30 km zone) off the FDNPP site. The 239+240P u activities were 4.16-5.52 mBq/m 3 and the 240 Pu/ 239 Pu atom ratios varied from 0.221 to 0.295. These values were compared with the baseline data for Pu distribution in the near coast seawaters before the FDNPP accident (2008-2010). The results suggested that there is no significant Pu contamination in seawater in the near coastal area off the FDNPP site from the accident two years after the accident. (author)

  2. Report on the effectiveness of flocculation for removal of 239Pu at concentrations of 1 pCi/L and 0.1 pCi/L

    International Nuclear Information System (INIS)

    Triay, I.R.; Bayhurst, G.K.; Mitchell, A.J.; Cisneros, M.R.; Efurd, D.W.; Roensch, F.R.; Rokop, D.J.; Aguilar, R.D.; Attrep, M.; Nuttall, H.E.

    1993-01-01

    The objective of this work is to assess the effectiveness of flocculation for the removal of Pu from Rocky Flats Plant (RFP) pond waters spiked with 239 Pu at the 1.0 and 0.1 pCi/L level. The flocculation treatment procedure is described in detail. Results are presented for treatment studies for the removal of Pu from C-2 pond water spiked with 239 Pu and from distilled water spiked with 239 Pu

  3. Recovery of 238PuO2 by Molten Salt Oxidation Processing of 238PuO2 Contaminated Combustibles (Part II)

    Science.gov (United States)

    Remerowski, Mary Lynn; Dozhier, C.; Krenek, K.; VanPelt, C. E.; Reimus, M. A.; Spengler, D.; Matonic, J.; Garcia, L.; Rios, E.; Sandoval, F.; Herman, D.; Hart, R.; Ewing, B.; Lovato, M.; Romero, J. P.

    2005-02-01

    Pu-238 heat sources are used to fuel radioisotope thermoelectric generators (RTG) used in space missions. The demand for this fuel is increasing, yet there are currently no domestic sources of this material. Much of the fuel is material reprocessed from other sources. One rich source of Pu-238 residual material is that from contaminated combustible materials, such as cheesecloth, ion exchange resins and plastics. From both waste minimization and production efficiency standpoints, the best solution is to recover this material. One way to accomplish separation of the organic component from these residues is a flameless oxidation process using molten salt as the matrix for the breakdown of the organic to carbon dioxide and water. The plutonium is retained in the salt, and can be recovered by dissolution of the carbonate salt in an aqueous solution, leaving the insoluble oxide behind. Further aqueous scrap recovery processing is used to purify the plutonium oxide. Recovery of the plutonium from contaminated combustibles achieves two important goals. First, it increases the inventory of Pu-238 available for heat source fabrication. Second, it is a significant waste minimization process. Because of its thermal activity (0.567 W per gram), combustibles must be packaged for disposition with much lower amounts of Pu-238 per drum than other waste types. Specifically, cheesecloth residues in the form of pyrolyzed ash (for stabilization) are being stored for eventual recovery of the plutonium.

  4. Recovery of 238PuO2 by Molten Salt Oxidation Processing of 238PuO2 Contaminated Combustibles (Part II)

    International Nuclear Information System (INIS)

    Remerowski, Mary Lynn; Dozhier, C.; Krenek, K.; VanPelt, C. E.; Reimus, M. A.; Spengler, D.; Matonic, J.; Garcia, L.; Rios, E.; Sandoval, F.; Herman, D.; Hart, R.; Ewing, B.; Lovato, M.; Romero, J. P.

    2005-01-01

    Pu-238 heat sources are used to fuel radioisotope thermoelectric generators (RTG) used in space missions. The demand for this fuel is increasing, yet there are currently no domestic sources of this material. Much of the fuel is material reprocessed from other sources. One rich source of Pu-238 residual material is that from contaminated combustible materials, such as cheesecloth, ion exchange resins and plastics. From both waste minimization and production efficiency standpoints, the best solution is to recover this material. One way to accomplish separation of the organic component from these residues is a flameless oxidation process using molten salt as the matrix for the breakdown of the organic to carbon dioxide and water. The plutonium is retained in the salt, and can be recovered by dissolution of the carbonate salt in an aqueous solution, leaving the insoluble oxide behind. Further aqueous scrap recovery processing is used to purify the plutonium oxide. Recovery of the plutonium from contaminated combustibles achieves two important goals. First, it increases the inventory of Pu-238 available for heat source fabrication. Second, it is a significant waste minimization process. Because of its thermal activity (0.567 W per gram), combustibles must be packaged for disposition with much lower amounts of Pu-238 per drum than other waste types. Specifically, cheesecloth residues in the form of pyrolyzed ash (for stabilization) are being stored for eventual recovery of the plutonium

  5. Influence of the goethite (α-FeOOH) surface on the stability of distorted PuO{sub 2} and PuO{sub 2-x} phases

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Sandra D.; Becker, Udo [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Earth and Environmental Sciences; Powell, Brian A. [Clemson Univ., Anderson, SC (United States). Environmental Engineering and Earth Science Dept.

    2016-07-01

    Experiments by [Powell, B. A., Dai, Z. R., Zavarin, M., Zhao, P. H., Kersting, A. B.: Stabilization of plutonium nano-colloids by epitaxial distortion on mineral surfaces. Environ. Sci. Technol. 45, 2698 (2011).] deduced the heteroepitaxial growth of a bcc Pu{sub 4}O{sub 7} phase when sorbed onto goethite from d-spacing measurements obtained from selected-area electron diffraction (SAED) patterns. The structural and/or chemical modification of Pu(IV) oxide (PO) nanocolloids upon sorption to goethite, in turn, affects colloidal-transport of Pu in the subsurface. In this study, molecular simulations were applied to investigate mechanisms affecting the formation of non-fcc PO phases and to understand the influence of goethite in stabilizing the non-fcc PO phase. Analyses of the structure, chemistry, and formation energetics for several bulk PuO{sub 2} and PuO{sub 2-x} phases, using ab initio methods, show that the formation of a non-fcc PO can occur from the lattice distortion (LD) of fcc PuO{sub 2} upon sorption and formation of a PO-goethite interface. To strain and non-uniformly distort the PuO{sub 2} lattice to match that of the goethite substrate at ambient conditions would require 88 kJ/mol Pu{sub 4}O{sub 8}. The formation of a hypostoichiometric PuO{sub 2-x} phase, such as the experimentally-deduced bcc, Ia anti 3 Pu{sub 4}O{sub 7} phase, requires more O-poor conditions and/or high energetic inputs (> +365 kJ/mol Pu{sub 4}O{sub 7} at O-rich conditions). Empirical methods were also applied to study the effect of lattice distortion on sorption energetics and adsorbate particle growth using simple heterointerfaces between cubic salts, where KCl clusters (notated as KCl{sub LD}) of varying size and lattice mismatch (LM) were sorbed to a NaCl cluster. When the lattice of a KCl{sub LD} cluster has <15% LM with that of a NaCl substrate, the sorption of KCl{sub LD} onto NaCl is exothermic (<-80 kJ/mol) and the KCl{sub LD} cluster can reach sizes of ∝2-5 nm on the Na

  6. Disagregation of (U, Pu)O2 fuels in molten sodium nitrate and oxides system

    International Nuclear Information System (INIS)

    Chou, T.S.

    1976-01-01

    An oxidation process based on the use of an alkali-nitrate melt has been considered as a possible head end step for the reprocessing of FBR spent fuels. The total alkali solubility in the nitrate melt was examined. It is influenced by the temperature. At 500 degC the alkali solubility in the sodium nitrate melt is about 17 mol %. Examining solidified mixture of sodium and nitrate or sodium oxides and nitrite by X-ray diffraction has revealed five unknown lattices. NaNO 3 .xNa 2 O 2 is cubic (a=8.71A), NaNO 2 .xNa 2 O 2 is tetragonal (a=5.939A, c=9.997A), NaNO 2 .xNa 2 O is cubic (a=10.586A). The structure of NaNO 3 .xNa 2 O and NaNO 3 .xNaO 2 could not be determined. The solubility of barium and ruthenium was briefly investigated. The reaction (U,Pu)O 2 with the alkaline sodium nitrate melt proceeds along the grain boundaries of the solid solution. Two steps have been recognized. First (U,Pu)O 2 is oxidized to (U,Pu)Osub(2+x) and in a subsequent step (U,Pu)Osub(2+x) reacts with sodium peroxide to form (U,Pu) 2 O 5 .xNa 2 O 2 . Disaggregation efficiency is a function of temperature, alkali concentration and physical properties of the pellets. High temperature and low alkali concentration lead to high efficiency. The structure of the reaction products (U,Pu)O 2 with alkaline NaNO 3 melt was shown to depend mainly on the alkali concentration. As the alkali concentration is lower than 2 mole % (U,Pu) 2 O 5 . Na 2 O 2 is the dominate phase. (U,Pu) 2 O 5 .3Na 2 O 2 corresponds to 6 mole % and over 11 mole % alkali, (U,Pu) 2 O 5 .xNa 2 O 2 becomes the main product. The solubility of the fuel (U,Pu) in the alkali sodium nitrate melt increases with the alkali concentration up to 6000-8000 ppm for uranium and 1200-1700 ppm for plutonium at 500 degC with only 5 mole % alkali. As a result of high losses of fissile material in the salt bath molten salt process must regarded as uneligible for a general head end step in fuel reprocessing. Nevertheless its application can still be

  7. {sup 238}Pu, {sup 239+240}Pu and {sup 241}Am levels in the terrestrial and aquatic environment of the Loire and Garonne rivers basins (France)

    Energy Technology Data Exchange (ETDEWEB)

    Rousseau, G.; Mokili, M.B.; Le Roy, C.; Pagano, V. [SUBATECH/IN2P3 (France); Gontier, G.; Boyer, C. [EDF-DPI-DIN-CIDEN (France); Chardon, P. [CNRS/IN2P3 (France); Hemidy, P.Y. [EDF-DPN-UNIE-GPRE-IEV (France)

    2014-07-01

    Plutonium and americium long-lived alpha emitter isotopes can be found in the environment because of atmospheric global fallout due to thermonuclear tests performed between 1945 and 1980, to the American SNAP 9A satellite explosion in 1964, to the Chernobyl nuclear power plant accident,... In France, the nuclear safety authority does not allow the release of artificial alpha emitters from nuclear power plants. Thus, monitoring is performed to verify the absence of these alpha emitters in liquid discharges to respect the limits set by the regulations. These thresholds ensure a very low dosimetric impact to the population compared to other radionuclides. With the objective of environmental monitoring around nuclear facilities, activity measurements of long-lived alpha emitters are carried out to detect the traces of these radionuclides. Analysis of low activity by alpha spectrometry after chemical steps were performed and used to determine the {sup 238}Pu, {sup 239+240}Pu and {sup 241}Am activities on a large set of environmental solid samples likely to be encountered in environmental monitoring as soils, sediments, terrestrial and aquatic bio-indicators. The samples collected in the terrestrial and aquatic environment of the Loire and Garonne rivers basins (France) was investigated for the 2009-2014 period. It was found that the mean activity concentration of the most frequently detected was for the radionuclide {sup 238}Pu: from <0.00031 to 0.0061 Bq/kg dry in terrestrial samples and from <0.00086 to 0.011 Bq/kg dry in aquatic samples; for the radionuclide {sup 239+240}Pu: from 0.00041 to 0.150 Bq/kg dry in terrestrial samples and from 0.0023 to 0.240 Bq/kg dry in aquatic samples and for the radionuclide {sup 241}Am: from <0.00086 to 0.087 Bq/kg dry in terrestrial samples and from 0.0022 to 0.120 Bq/kg dry in aquatic samples. {sup 238}Pu/{sup 239+240}Pu and {sup 241}Am/{sup 239+240}Pu ratios determined are in accordance with an environmental contamination due to

  8. Determination of 239Pu and 240Pu isotope ratio for a nuclear bomb particle using X-ray spectrometry in conjunction with γ-ray spectrometry and non-destructive α-particle spectrometry

    International Nuclear Information System (INIS)

    Poellaenen, R.; Ruotsalainen, K.; Toivonen, H.

    2009-01-01

    A nuclear bomb particle from Thule containing Pu and U was analyzed using X-ray spectrometry in combination with γ-ray spectrometry and non-destructive α-spectrometry. The main objective was to investigate the possibility to determine the 239 Pu and 240 Pu isotope ratios. Previously, X-ray spectrometry together with the above-mentioned methods has been successfully applied for radiochemically processed samples, but not for individual particles. In the present paper we demonstrate the power of non-destructive analysis. The 239 Pu/( 239 Pu+ 240 Pu) atom ratio for the Thule particle was determined, using two different approaches, to be 0.93±0.07 and 0.91±0.05. These results are consistent with weapons-grade material and the results obtained by other investigators.

  9. Redox potentials of PuO{sub 2}{sup 2+}/PuO{sub 2}{sup +} and Pu{sup 4+}/Pu{sup 3+} at different ionic strengths and temperatures; entropy and heat capacity; Potentiels Redox des couples PuO{sub 2}{sup 2+}/PuO{sub 2}{sup +} et Pu{sup 4+}/Pu{sup 3+} a force ionique et temperature variables. Entropie et capacite calorifique

    Energy Technology Data Exchange (ETDEWEB)

    Capdevila, H.; Vitorge, P.

    1994-05-01

    The reversible redox potentials of the Plutonium couples are measured by using cyclic voltammetry, in perchloric media at ionic strength, I from 0,5 M to 3M, and temperature, T, from 5 deg C to 65 deg C. At each T, experimental results, E(T,I), are extrapolated to I = O by applying the Specific Interaction Theory (S.I.T.) to get interaction coefficients, {Delta} is element of (T), and E(T,O) (e.g. standard potentials when T = 25 deg C). At T = 25 deg C the numerical values of the potentials of all the Pu couples are nearly the same. It is then not easy to detect a systematic error due to disproportionation or redox impurity. This can explain some discrepancy on numerical values already published. We finally propose ``recommended values`` of the reversible redox potentials. As a first approximation, the variations of these potentials seem to be quite linear versus temperature: entropy variation versus T is small. But taking into account heat capacity that is involved in the E(T,I) second order derivative, usually improves the fitting. A second order expansion of {epsilon}(T) and of the Debye Huckel term, D(T) are used to propose equations that account for simultaneous ionic strength and temperature influences on G, S, Cp, H, and lg K. These equations, in particular those modelling the ionic strength influence on {Delta}S, {Delta}Cp, and {Delta}H are first checked for published mean activity coefficients of HCI and NaCI. Small discrepancy between the numerical values of entropy changes of actinides redox couples, deduced from electrochemical and calorimetric techniques are discussed. (authors). 27 refs., 6 tabs., 10 figs.

  10. A multi-radionuclide approach to evaluate the suitability of 239+240Pu as soil erosion tracer

    International Nuclear Information System (INIS)

    Meusburger, Katrin; Mabit, Lionel; Ketterer, Michael; Park, Ji-Hyung; Sandor, Tarjan; Porto, Paolo; Alewell, Christine

    2016-01-01

    Fallout radionuclides have been used successfully worldwide as tracers for soil erosion, but relatively few studies exploit the full potential of plutonium (Pu) isotopes. Hence, this study aims to explore the suitability of the plutonium isotopes 239 Pu and 240 Pu as a method to assess soil erosion magnitude by comparison to more established fallout radionuclides such as 137 Cs and 210 Pb ex . As test area an erosion affected headwater catchment of the Lake Soyang (South Korea) was selected. All three fallout radionuclides confirmed high erosion rates for agricultural sites (> 25 t ha −1 yr −1 ). Pu isotopes further allowed determining the origin of the fallout. Both 240 Pu/ 239 Pu atomic ratios and 239+240 Pu/ 137 Cs activity ratios were close to the global fallout ratio. However, the depth profile of the 239+240 Pu/ 137 Cs activity ratios in undisturbed sites showed lower ratios in the top soil increments, which might be due to higher migration rates of 239+240 Pu. The activity ratios further indicated preferential transport of 137 Cs from eroded sites (higher ratio compared to the global fallout) to the depositional sites (smaller ratio). As such the 239+240 Pu/ 137 Cs activity ratio offered a new approach to parameterize a particle size correction factor that can be applied when both 137 Cs and 239+240 Pu have the same fallout source. Implementing this particle size correction factor in the conversion of 137 Cs inventories resulted in comparable estimates of soil loss for 137 Cs and 239+240 Pu. The comparison among the different fallout radionuclides highlights the suitability of 239+240 Pu through less preferential transport compared to 137 Cs and the possibility to gain information regarding the origin of the fallout. In conclusion, 239+240 Pu is a promising soil erosion tracer, however, since the behaviour i.e. vertical migration in the soil and lateral transport during water erosion was shown to differ from that of 137 Cs, there is a clear need for a

  11. Criticality safety study of Pu contaminated carbon waste stored in 100 L steel drums

    International Nuclear Information System (INIS)

    Anno, J.; Simonneau, M.

    1995-01-01

    The notion of the minimum critical areal density (D minca ) used to ensure the Criticality-Safety of poor solid waste is recalled with its deficiencies. D minca is assumed constant, independent of the fissile material concentration. This assumption is only true for unreflected mediums. Corrective factors are established. Furthermore, the usual norm of the Pu-H 2 O, which is 0.20 g/cm 2 , (concrete reflected) is greater than that for other mediums, such as Pu contaminated graphite waste (Pu-C), which is 0.036 g/cm 2 . D minca calculated on infinite slabs is confirmed by calculations on infinite planar multilayers arrays of 100 l cubical waste drums. Moreover, d minca increases linearly with the steel thickness of the drums' walls and goes up to 0.17 g/cm 2 for 0.105 cm of steel. The safety analysis on a real storage case takes into account the limited amount of Pu (100 g) and C (100 kg), the minimum thickness of 0.07 cm of drums' steel, their geometrical arrangement, the heterogeneity and size of contamination and the occurrence of neutronic poison (N and Cl) in the waste. Because of these parameters, the Keff are very less than 0.95 and the taken norm of 0.1 g/cm 2 for the Pu-C waste is fulfilled. Finally, it is demonstrated that the mixing of Pu-C waste drums and Pu-H 2 O wastes drums is allowed. (authors). 14 refs., 5 figs., 6 tabs

  12. Low-level inhaled-239PuO2 life-span studies in rats

    International Nuclear Information System (INIS)

    Sanders, C.L.; McDonald, K.E.; Killand, B.W.; Mahaffey, J.A.; Cannon, W.C.

    1986-01-01

    This study determined the dose-response curve for lung tumor incidence in rats after inhalation of high-fired 239 PuO 2 , which gave radiation doses to the lung of from ∼5 to >1000 rads. Exposed rats were given a single, nose-only, inhalation exposure to 169 Yb- 239 PuO 2 aerosol (AMAD, 1.6 +- 0.11 μm). The effective half-time for 169 Yb in the lung was 14 days, whereas ∼76% of 239 Pu was cleared with a half-time of 20 days and 24%, with a half-time of 180 days. Whole-body counting for 169 Yb at 14 days after exposure was an accurate method for determining 239 Pu IAD in individual rats, even at IAD's as low as 0.60 nCi of 239 Pu. The 239 Pu lung-clearance curve and an equation describing changes in lung weight with body weight and age were used to determine lung radiation doses. The IAD's of exposure groups were 0.60 +- 0.15 nCi of 239 Pu (1000 rats), 0.98 +- 0.25 (531 rats), 2.4 +- 0.69 (209 rats), 5.7 +- 1.2 (98 rats), and 7.5 +- 2.0 to 150 +- 37 nCi (300 rats); corresponding radiation doses to the lung estimated at 3 years after exposure were 8.3, 14, 33, 79, and 100 to 2100 rads, respectively. 71 refs., 5 figs., 4 tabs

  13. Peculiarities of 239,240Pu behaviour in flood-plain soils of the Techa river

    International Nuclear Information System (INIS)

    Mikhailovskaya, L.N.; Molchanova, I.V.; Karavaeva, E.N.

    2004-01-01

    The Techa river was contaminated with the liquid nuclear waste discharged from the nuclear plant 'Mayak' within 1949-1956 years. In 1999-2002 flood-plain soils of the Techa river were investigated and the levels of content, a migration and a vertical distribution of 239,240 Pu in the flood-plain soils were studied. Reference plots were located in the pre-bed and in central flood plain at different distances from the source of contamination (78-240 km). It was shown that in the soils of the pre-bed the content of Pu isotopes was decreasing from 10.5 to 2.8 kBq/m 2 with the distance from the plant 'Mayak'. Besides, a non-uniform spatial distribution of 239,240 Pu was found in those plots, which were at the same distance from the source of the contamination. As a rule, the central flood plain (25-100 m from the river-bed) was contaminated with 239,240 Pu less than the area in the pre-bed (5-20 m from the the river-bed). Thus, in the area of the middle length of the river the density of the soil contamination with 239,240 Pu of the central flood plain is 0.3 to 0.8 kBq/m 2 and that of the pre-bed is 1.0 to 4.7 kBq/m 2 at a maximum migration depth being 25 to 30 cm and 40 to 50 cm, respectively. The determined value of the 239,240 Pu/ 137 Cs ratio proves that rates of the vertical migration of the Pu isotopes in the flood plain soils of the Techa river are comparable and higher (in some cases) than those of 137 Cs. (author)

  14. Removal of 238Pu(IV) from mice by poly-catechoylate, -hydroxamate or -hydroxypyridinonate ligands

    International Nuclear Information System (INIS)

    Durbin, P.W.; Jeung, N.; Rodgers, S.J.; Turowski, P.N.; Weitl, F.L.; White, D.L.; Raymond, K.N.; California Univ., Berkeley, CA

    1989-01-01

    Binding of actinide (IV) by plasma proteins impedes excretion. Facilitation of elimination with chelating agents is the only known way to reduce carcinogenic risk. Iron-sequestering agents produced by micro-organisms contain metal-binding groups that bind Pu(IV) at pH 7.4 (catechol, CAM, in enterobactin; hydroxamate, X, in the ferrioaxamines; hydroxypyridinone, HOPO). Our synthetic ligands contain up to four such groups linked by alkyl chains or attached to desferrioxamine (DFO) or diethylene-triamine-pentaacetic acid (DPTA). 238 Pu excretion was tested in mice given 30 μmol.kg -1 of a ligand. Ligands that removed as much or more Pu than CaNa 3 -DTPA(≥70% of injected Pu(% ID)) are, in decreasing order of effectiveness: (1) Fe(III)-3,4,3-LIHOPO, (2) DFO-HOPO, (3) 3,4,3-LIHOPO, (4) 3,4,3-LICAM(C). Orally administered ligands 1-4, (5) 3,4,3-LICAM(S) and (6) ZnNa-DTPA-DX removed as much or more Pu than CaNa 3 -DTPA (≥ 15% ID). Ligands 1-4 and 6 injected 24 h after the Pu removed ≥ 5% ID more than control excretion (equivalent to or better than CaNa 3 -DTPA). All the new ligands at a dosage of 0.3 μmol.kg -1 removed a significant amount of Pu compared with controls: CaNa 3 -DTPA was ineffective. Ligand 3 is acutely toxic at high dosage, but the others appear to be of low toxicity. The HOPO ligands and ZnNa-DTPA-DX are recommended for further study. (author)

  15. Development of prototype induced-fission-based Pu accountancy instrument for safeguards applications.

    Science.gov (United States)

    Seo, Hee; Lee, Seung Kyu; An, Su Jung; Park, Se-Hwan; Ku, Jeong-Hoe; Menlove, Howard O; Rael, Carlos D; LaFleur, Adrienne M; Browne, Michael C

    2016-09-01

    Prototype safeguards instrument for nuclear material accountancy (NMA) of uranium/transuranic (U/TRU) products that could be produced in a future advanced PWR fuel processing facility has been developed and characterized. This is a new, hybrid neutron measurement system based on fast neutron energy multiplication (FNEM) and passive neutron albedo reactivity (PNAR) methods. The FNEM method is sensitive to the induced fission rate by fast neutrons, while the PNAR method is sensitive to the induced fission rate by thermal neutrons in the sample to be measured. The induced fission rate is proportional to the total amount of fissile material, especially plutonium (Pu), in the U/TRU product; hence, the Pu amount can be calibrated as a function of the induced fission rate, which can be measured using either the FNEM or PNAR method. In the present study, the prototype system was built using six (3)He tubes, and its performance was evaluated for various detector parameters including high-voltage (HV) plateau, efficiency profiles, dead time, and stability. The system's capability to measure the difference in the average neutron energy for the FNEM signature also was evaluated, using AmLi, PuBe, (252)Cf, as well as four Pu-oxide sources each with a different impurity (Al, F, Mg, and B) and producing (α,n) neutrons with different average energies. Future work will measure the hybrid signature (i.e., FNEM×PNAR) for a Pu source with an external interrogating neutron source after enlarging the cavity size of the prototype system to accommodate a large-size Pu source (~600g Pu). Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Dosimetry and response in rat pulmonary epithelium following inhalation of 239PuO2

    International Nuclear Information System (INIS)

    Rhoads, K.; Mahaffey, J.A.; Sanders, C.L.

    1983-01-01

    The distribution of inhaled 239 PuO 2 and pathologic changes have been studied in the lung of rats. The clearance of inhaled 237 239 PuO 2 from the lung is a function of the amount of deposited Pu with a decrease in early alveolar clearance with increasing lung burden. With increasing time post-exposure there is a greater concentration of PuO 2 and an increased aggregation of PuO 2 particles in subpleural regions of the lung. Fibrotic and metaplastic lesions in the lung were usually focal, being found in subpleural regions associated with aggregates of PuO 2 . An average of 12 +- 6 percent of the lung volume was fibrotic at 530 days after an initial alveolar deposition of 180 nCi 239 Pu. Lung tumors occupied 4 +- 6 percent and epithelial metaplasias less than 1 percent of the lung volume at this time. Cell proliferation as assayed by tritiated thymidine autoradiography was greater in fibrotic, metaplastic and neoplastic regions than in areas of normal alveolar-bronchiolar epithelium. Turnover times ranged from about 6 days for fibrotic lesions to 1 to 3 days for metaplastic and neoplastic lesions. The lung tumor doubling times were 57 to 116 days due to tumor cell necrosis and other factors that limit tumor cell survival. Cell proliferation rates for adenomatous metaplasia were similar to those for adenocarcinoma while those for squamous cell metaplasia were similar to those for squamous cell carcinoma. Squamous lesions exhibited a more rapid growth than did adenomatous lesions

  17. Minimum pickup velocity (U{sub pu}) of nanoparticles in gas–solid pneumatic conveying

    Energy Technology Data Exchange (ETDEWEB)

    Anantharaman, Aditya [Nanyang Technological University, School of Chemical and Biomedical Engineering (Singapore); Ommen, J. Ruud van [Delft University of Technology, Department of Chemical Engineering (Netherlands); Chew, Jia Wei, E-mail: JChew@ntu.edu.sg [Nanyang Technological University, School of Chemical and Biomedical Engineering (Singapore)

    2015-12-15

    This paper is the first systematic study of the pneumatic conveying of nanoparticles. The minimum pickup velocity, U{sub pu}, of six nanoparticle species of different materials [i.e., silicon dioxide (SiO{sub 2}), aluminum oxide (Al{sub 2}O{sub 3}), and titanium dioxide (TiO{sub 2})] and surfaces (i.e., apolar and polar) was determined by the weight loss method. Results show that (1) due to relative lack of hydrogen bonding, apolar nanoparticles had higher mass loss values at the same velocities, mass loss curves with accentuated S-shaped profiles, and lower U{sub pu} values, (2) among the three species, SiO{sub 2}, which has the lowest Hamaker coefficient, exhibited the greatest discrepancy between apolar and polar surfaces with respect to both mass loss curves and U{sub pu} values, (3) U{sub mf,polar}/U{sub mf,apolar} was between 1 and 3.5 times that of U{sub pu,polar}/U{sub pu,apolar} due to greater extents of hydrogen bonding associated with U{sub mf}, (4) U{sub pu} values were at least an order-of-magnitude lower than that expected from the well-acknowledged U{sub pu} correlation (Kalman et al., Powder Technol 160:103–113, 2005) due to agglomeration, (5) although nanoparticles should be categorized as Zone III (Kalman et al. 2005) (or Geldart group C, Powder Technol 7:285–292, 1973), the nanoparticles, and primary and complex agglomerates agreed more with the Zone I (or Geldart group B) correlation.

  18. Studies on extraction behaviour of U (VI) and Pu (IV) by Aliquat-336 encapsulated in microporous polymer beads

    International Nuclear Information System (INIS)

    Parikh, K.J.; Kedari, C.S.; Pandit, S.S.; Tripathi, S.C.; Dwivedi, C.; Singh, K.K.; Kumar, M.; Bajaj, P.N.

    2009-01-01

    Aliquat-336 encapsulated microporous polymeric beads (AEPB) were prepared to investigate their applicability for the solid-liquid extraction Pu (IV) from nitric acid solutions. Batch equilibration studies on the extractions of U (VI) and Pu (IV) from aqueous solutions using AEPB have been carried out at different concentrations of nitric acid and sodium nitrate. Extraction of Pu (IV) increases with increasing concentration of nitrate ions in the aqueous phase where as extraction of U (VI) remains less than 5% for all the aqueous conditions studied. Polymeric beads appeared to be less stable at higher nitric acid concentrations as the extraction of Pu (IV) was found to be lowered above 4 M HNO 3 concentration. The maximum Pu (IV) uptake by AEPB was 0.84 μg per mg of beads. Pu (IV)from loaded polymer can be back extracted using dilute nitric acid or ascorbic acid solution. (author)

  19. Studies on Pu(IV)/(III)-oxalate precipitation from nitric acid containing high concentration of calcium and fluoride ions

    International Nuclear Information System (INIS)

    Kalsi, P.K.; Pawar, S.M.; Ghadse, D.R.; Joshi, A.R.; Ramakrishna, V.V.; Vaidya, V.N.; Venugopal, V.

    2003-01-01

    Plutonium (IV)/(III) oxalate precipitation from nitric acid solution, containing large amount of calcium and fluoride ions was investigated. It was observed that direct precipitation of Pu (IV) oxalate from nitric acid containing large amount of calcium and fluoride ions did not give good decontamination of Pu from calcium and fluoride impurities. However, incorporation of hydroxide precipitation using ammonium hydroxide prior to Pu (IV) oxalate precipitation results into PuO 2 with much less calcium and fluoride impurities. Whereas, good decontamination from calcium and fluoride impurities could be obtained by employing Pu (III) oxalate precipitation directly from nitric acid containing large amount of calcium and fluoride ions. A method was also developed to recover Pu from the oxalate waste containing calcium and fluoride ions. (author)

  20. Stability constants important to the understanding of plutonium in environmental waters, hydroxy and carbonate complexation of PuO2+

    International Nuclear Information System (INIS)

    Bennett, D.A.; Lawrence Berkeley Lab., CA

    1990-01-01

    The formation constants for the reactions PuO 2 + + H 2 O = PuO 2 (OH) + H + and PuO 2 + + CO 3 2 = PuO 2 (CO 3 ) - were determined in aqueous sodium perchlorate solutions by laser-induced photoacoustic spectroscopy. The molar absorptivity of the PuO 2 + band at 569 nm decreased with increasing hydroxide concentration. Similarly, spectral changes occurred between 540 and 580 nm as the carbonate concentration was increased. The absorption data were analyzed by the non-linear least-squares program SQUAD to yield complexation constants. Using the specific ion interaction theory, both complexation constants were extrapolated to zero ionic strength. These thermodynamic complexation constants were combined with the oxidation-reduction potentials of Pu to obtain Eh versus pH diagrams. 120 refs., 35 figs., 12 tabs

  1. Variation of 137Cs and 239,240Pu concentrations in shellfishes on the coast of Ibaraki prefecture

    International Nuclear Information System (INIS)

    Fujita, Hiroki; Nakano, Masanao

    2007-01-01

    The concentrations of 137 Cs and 239,240 Pu in shellfishes collected from the coast around the Tokai Reprocessing Plant (TRP) from 1975 to 2005 were analyzed for environmental radiological monitoring. The measured concentrations of 238 Pu were under the detection limits and these concentrations of 137 Cs and 239,240 Pu showed no significant short-term increase tendency. It was confirmed that 137 Cs and 239,240 Pu in shellfishes around the TRP were derived from the past atmospheric nuclear weapons tests. Also the probability plot of 239,240 Pu concentration was dependent on the shellfish species (bivalve and abalone). It was presumed that the different of feeding behavior of bivalve and abalone caused the difference of the probability plot of 239,240 Pu concentration. (author)

  2. Hematological responses after inhaling {sup 238}PuO{sub 2}: An extrapolation from beagle dogs to humans

    Energy Technology Data Exchange (ETDEWEB)

    Scott, B.R.; Muggenburg, B.A.; Welsh, C.A.; Angerstein, D.A.

    1994-11-01

    The alpha emitter plutonium-238 ({sup 238}Pu), which is produced in uranium-fueled, light-water reactors, is used as a thermoelectric power source for space applications. Inhalation of a mixed oxide form of Pu is the most likely mode of exposure of workers and the general public. Occupational exposures to {sup 238}PuO{sub 2} have occurred in association with the fabrication of radioisotope thermoelectric generators. Organs and tissue at risk for deterministic and stochastic effects of {sup 238}Pu-alpha irradiation include the lung, liver, skeleton, and lymphatic tissue. Little has been reported about the effects of inhaled {sup 238}PuO{sub 2} on peripheral blood cell counts in humans. The purpose of this study was to investigate hematological responses after a single inhalation exposure of Beagle dogs to alpha-emitting {sup 238}PuO{sub 2} particles and to extrapolate results to humans.

  3. Sup(239,240)Pu in estuarine and shelf waters of the north-eastern United States

    International Nuclear Information System (INIS)

    Sholkovitz, E.R.; Mann, D.R.

    1987-01-01

    The distribution of sup(239,240)Pu between dissolved and particulate forms has been measured in four estuaries on the north-east coast of the United States (Connecticut River, Delaware Bay, Chesapeake Bay, and Mullica River). The data cover the whole salinity range from freshwater input to shelf waters at 3.5% and includes one profile from a nearly anoxic basin in the Chesapeake Bay. In the organic-rich Mullica River estuary, large-scale removal of riverine dissolved sup(239,240)Pu occurs at low salinities due to salt-induced coagulation, a mechanism analogous to that for iron and humic acids. Within the 0 to 2.5-3.5% zone in the other three estuaries, the activity of dissolved sup(239,240)Pu increases almost conservatively. The activities of particulate sup(239,240)Pu are highest in the more turbid waters of low salinity regime (0-1.5%), but become increasingly insignificant with respect to dissolved sup(239,240)Pu as salinities increase. At higher salinities corresponding to shelf water, there is a sharp increase in dissolved sup(239,240)Pu activity. The dissolved sup(239,240)Pu activity within each estuary appears to be inversely related to the flushing time of water. The sharp decrease in dissolved sup(239,240)Pu activities between shelf and estuarine waters appears to be driven by removal within the estuaries themselves rather than on the shelf. Dissolved sup(239,240)Pu activities are lower in the nearly-anoxic bottom waters of Chesapeake Bay indicating enhanced removal by redox transformation of Pu [i.e., Pu(V) to Pu(IV)]. (author)

  4. Plutonium concentrations and Pu/Am ratios in small vertebrates from NAEG Intensive Study Areas of NTS

    International Nuclear Information System (INIS)

    Bradley, W.G.; Moor, K.S.; Naegle, S.R.

    1977-01-01

    Radioecological studies of small vertebrates in Pu-contaminated areas of NTS began in spring 1972 and have continued to date. Species conposition, relative abundance, and other pertinent ecological data have been presented in previous reports. In addition, data analysis of Pu and Am concentrations in selected rodent and lizard species has been presented for all NAEG Intensive Study Areas. This report provides further analysis of Pu concentration in small vertebrates of Areas 5 and 11, NTS

  5. Evaluation of the U-Pu residual mass from spent fuel assemblies with passive and active neutronic methods

    International Nuclear Information System (INIS)

    Bignan, G.; Martin-Deidier, L.

    1991-01-01

    The interpretation of passive and active neutronic measurements to evaluate the U-Pu residual mass in spent fuel assemblies is presented as follows: passive neutron measurements are well correlated to the plutonium mass, active neutron measurements give information linked to the fissile mass content of the assembly ( 235 U + 239 Pu + 241 Pu) and, using the passive neutron measurement, lead to the 235 U mass content of the assemblies

  6. Separation of Pu from soil prior to determination by ICP-MS

    International Nuclear Information System (INIS)

    Nygren, U.; Baxter, D.C.

    2002-01-01

    In the determination of plutonium in environmental materials by ICP-MS, chemical separation is often needed to remove, e.g., heavy sample matrices and interference from UH + on m/z 239. This separation can be, and often is, performed in the same way as for alpha-spectrometric analysis. There are, however, somewhat different demands on separation for ICP-MS compared to alpha-spectrometry, but so far little has been published on the optimisation of separation procedures for plutonium determination by ICP-MS. This paper describes the development of a separation procedure especially suited for the determination of Pu by ICP-MS. Focus has been on parameters such as chemical yield of plutonium and decontamination from uranium, as well as time requirements and ease of performance. The separation of plutonium was performed using various resins, such as anion exchange resin and extraction chromatographic materials. The procedures were carried out on water spiked with 238 U and 240 Pu to concentrations of approximately 300 ppb and 50 ppt, respectively. The basic separation procedure was: 1. Adjustment of oxidation state for Pu 2. Loading on column 3. Rinsing using 4*5 free column volumes (FCVs) of load solution - if needed in combination with 1*5 FCVs of an other rinsing agent 4. Elution of Pu - if needed followed by evaporation and dissolution in a solution suitable for ICP-MS determination 5. Determination by high resolution ICP-MS The elution of plutonium was performed using various media, based on either reduction of Pu(IV) to Pu(III) or complex formation. The chemical yield of plutonium and the decontamination from uranium for various resin/elution combinations can be seen in Figs. 1 and 2. It was found that the most efficient separation procedure in terms of yield and uranium decontamination was the combination of two extraction chromatographic materials, UTEVA followed by TRU, and elution of Pu by 0.1 % 1-hydroxyethane-1,1-diphosphonic acid (HEDPA). In this procedure

  7. Uptake and distribution of Pu, Am, Cm and Np in four plant species

    Energy Technology Data Exchange (ETDEWEB)

    Schreckhise, R G; Cline, J F [Battelle, Pacific Northwest Laboratories, Richland, WA (United States)

    1978-12-01

    The relative uptake of the nitrate forms of {sup 238}Pu, {sup 239}Pu, {sup 241}Sm, {sup 244}Cm and {sup 237}Np from soil into selectee parts of four different plant species grown under field conditions were observed. Cheatgrass (Bromus tectorum L.), peas (Pisum sativum, var. Blue Bonnet), barley (Hordeum vulgare, var. U. Cal. Briggs), and alfalfa (Medicago sativa, var. Ranger) were grown outdoors in contaminated soil contained in small weighing lysimeters constructed from 13.2 cm diameter by 1-meter-long polyvinyl chloride pipe. The amended soil, containing 0.1 to 1.0 mCi of each isotope individually per 3.4 kg soil, was situated in a 20 cm band and covered by 10 cm of uncontaminated soil to eliminate chances of windblown contamination to the surrounding environs. The plants were harvested at maturity, divided into selected components and radiochemically analyzed by alpha-energy analysis. There did not appear to be any effect of soil concentration on the plant uptake of {sup 238}Pu, {sup 239}Pu, {sup 241}Am or {sup 244}Cm for the two levels utilized (approximately 0.03 and 0.3 {mu}Ci/g soil). The relative uptake of {sup 238}Pu and {sup 239}Pu were not significantly different. Likewise, {sup 241} Am uptake values were not significantly different from the {sup 244}Cm values. The relative plant uptake of the four different transuranium element was: Np > Cm {approx} Am > Pu. The relative uptake values of Np were 2,200 to 45,000 times greater than for Pu, while Am and Cm values were 10 to 20 times greater. The seeds were significantly lower than the rest of the above ground plant parts for all four transuranics. The legumes accumulated approximately ten times more than the grasses. A hypothetical comparison of the radionuclide content of plants grown in soil contaminated with LMFBR fuels indicate that Am, Cm and Np concentrations would exceed Pu values. (author)

  8. Behavior and biological action of 239Pu while getting into skin abrasions

    International Nuclear Information System (INIS)

    Bazhin, A.G.; Lyubchanskij, Eh.R.; Nifatov, A.N.; Sinyakov, E.G.

    1983-01-01

    The levels of the radionuclide resorption are given through abrasions in applying 224-906 kBk of 239 Pu on them (0.6=1.5 % for 600 days), the nature of distribution and parameters of its exchange in the test skin area, skeleton and liver. Data of morphological studies are presented. The influence of prolonged complexon therapy on 239 Pu content in organs and tissues, mean life span, the frequency of appearance of morphological changes in test skin areas with the contamination density of 40; 184 and 722 kBk of 239 Pu/cm 2 and the frequency of tumor development including malignancy in case of applying 224 and 906 kBk of 239 Pu to abrasions is evaluated. It has been established that as a result of complexon therapy dosage exposure of the skeleton lessened by 4-5 times, the mean life span of rats with tumors increased, the development of osteosarcomas caused by Pu reduced from 23.6-36.2 to 4.4-6.2 % but the therapy did not influence the frequency of pathological changes in the test skin area

  9. Influence of inhaled Ca-DTPA on the long-term effects of inhaled Pu nitrate

    International Nuclear Information System (INIS)

    Ballou, J.E.; Dagle, G.E.; McDonald, K.E.; Buschbom, R.L.

    1975-01-01

    Inhaled Ca-DTPA administered to rats in 6 weekly, one-hour treatments of 3 mg/rat did not affect weight gain or life-span compared to Pu burdened animals (78 nCi ILB) or nontreated controls. In addition, the drug did not appear to promote the development of malignant lung tumors and bone tumors in Pu burdened rats although one rat exposed only to Ca-DTPA aerosols did develop a malignant lung tumor. This single lung tumor can not be considered significant although the normal incidence of this lesion is quite low. Inhaled Ca-DTPA therapy administered 20 days after Pu inhalation showed little effect in reducing the lung burden of plutonium. Skeletal deposition was decreased possibly because Ca-DTPA was administered during a time of active translocation of the inhaled Pu when Pu may have been available for chelation in the blood. Inhaled Ca-DTPA therapy did not appear to be beneficial in reducing the number of malignant lung tumors or bone tumors in plutonium burdened rats but on the other hand the chelate did not appear to promote these lesions. (U.S.)

  10. Present status and future plans of the study for preparation of Pu reference materials

    International Nuclear Information System (INIS)

    Sumi, Mika; Kageyama, Tomio; Suzuki, Toru

    2007-01-01

    All accountancy analysis at the Plutonium Fuel Development Center of JAEA is performed by isotope dilution mass spectrometry with well-characterized standard materials. Though Pu reference materials has been supplied from foreign country, importing those Pu materials is gradually becoming more difficult and may be almost impossible to import them in future. Thus, in order to establish the capability and expertise for the preparation of Pu reference materials, JAEA has started collaborative work with NBL who has high skills for preparing and supplying nuclear reference materials for long periods. One of the targets of this collaboration is preparation of standard material for IDMS (LSD spike). MOX powder which has been stored in JAEA was dissolved and Purified to obtain Pu solution. A small portion of the Purified solution was transported to NBL for analysis. LSD spike will be prepared from this Pu solution and then validation analysis and performance test including stability test will be performed with NBL and JAEA. This report presents status and future plans for the collaboration work. (author)

  11. Determination of the neutron-induced fission cross section of 242Pu

    International Nuclear Information System (INIS)

    Koegler, Toni Joerg

    2016-01-01

    Neutron induced fission cross sections of actinides like the Pu-isotopes are of relevance for the development of nuclear transmutation technologies. For 242 Pu, current uncertainties are of around 21%. Sensitivity studies show that the total uncertainty has to be reduced to below 5% to allow for reliable neutron physics simulations. This challenging task was performed at the neutron time-of-flight facility of the new German National Center for High Power Radiation Sources at HZDR, Dresden. Within the TRAKULA project, thin, large and homogeneous deposits of 235 U and 242 Pu have been produced successfully. Using two consecutively placed fission chambers allowed the determination of the neutron induced fission cross section of 242 Pu relative to 235 U. The areal density of the Plutonium targets was calculated using the measured spontaneous fission rate. Experimental results of the fast neutron induced fission of 242 Pu acquired at nELBE will be presented and compared to recent experiments and evaluated data. Corrections addressing the neutron scattering are discussed by using results of different neutron transport simulations (Geant 4, MCNP 6 and FLUKA).

  12. Background distributions of 239+240Pu and 137Cs of upland soil in Rokkasho, Japan

    International Nuclear Information System (INIS)

    Ohtsuka, Yoshihito; Iyogi, Takashi; Kakiuchi, Hideki; Hisamatsu, Shunichi; Inaba, Jiro

    2003-01-01

    The background distributions of Pu and 137 Cs in soil were investigated in Rokkasho, Aomori Prefecture, where the first commercial nuclear fuel reprocessing plant in Japan is now being constructed. Soil core samples to 1 m depth were collected at 13 upland fields in Rokkasho and control sites in Hachinohe and Hirosaki. Since fields under yam (Dioscorea babatus) cultivation, which is a common crop in Rokkasho, were dug to approximately 1 m depth at harvesting, depth profiles of fallout radionuclides are heavily disturbed for most fields in Rokkasho. The mean inventories of 239+240 Pu and 137 Cs in three fields with no yam cultivation history were 116 Bq m -2 and 3.4 kBq m -2 , respectively and similar to values in Hachinohe. However, the inventories were approximately a half of those in Hirosaki. The mean ratio of 239P u/ 240 Pu for all studied fields was 0.18±0.04, and similar to that of global fallout. The Pu concentrations correlate very well with 137 Cs (r=0.97) in spite of heavy disturbance of soil, and the ratio of 239+240 Pu/ 137 Cs was 0.037±0.007, which is a typical value for global fallout. (author)

  13. Respiratory tract tumors in Syrian hamsters following inhalation of Pu--ZrO2 particles

    International Nuclear Information System (INIS)

    Thomas, R.G.; Smith, D.M.

    1979-01-01

    Inhalation of radionuclide-bearing particles remains one of the most intensely pursued problems concerning the nuclear industry. This route of entry is generally accepted as the most probable, in case of human exposure, with ingestion being the other prominent source of concern. Many laboratory investigations, such as those reported here, continue to evaluate the possible consequences that may present health problems to the public domain. Syrian hamsters of both sexes received either inhaled (INH) PuO 2 /ZrO 2 particles, intravenous (IV) PuO 2 /ZrO 2 microspheres, a combination of INH PuO 2 /ZrO 2 particles and injected PuO 2 /ZrO 2 microspheres, or no radionuclides (controls). The INH particles and IV microspheres were tagged with γ-emitting 57 Co to facilitate whole body counting and establishment of retention curves. Total lung burdens ranged from 8 nCi to 143 nCi. Significant numbers of primary lung tumors (5 to 50% per group) were induced in those animals that received INH exposures. Additional α radiation administered via Pu-laden IV microspheres had little or no effect on tumor production or nonneoplastic, degenerative changes in the respiratory tract

  14. Crystallography and magnetic properties of transuranium element oxygen compounds (Np, Pu and Am)

    International Nuclear Information System (INIS)

    Tabuteau, Alain.

    1981-05-01

    This paper includes: 1) The brief description of the experimental techniques used for analyzing very small quantities of solid radioactive compounds (differential thermal micro-analyses, diffraction of X rays, magnetic susceptibility and Moessbauer resonance). 2) The methods of synthesis of the ternary oxides of transuranic elements at oxidation degrees III (Pu 2 MoO 6 , Pu 2 WO 6 , Pu 2 (WO 4 ) 3 , Am 2 MoO 6 , Am 2 WO 6 , Am 2 (MoO 4 ) 3 and Am 2 (WO 4 ) 3 ) and at degree IV (Np(VO 3 ) 4 , Np(MoO 4 ) 2 , Np(WO 4 ) 2 and Pu(MoO 4 ) 2 ). The drawing up of liquid-solid balance diagrams enabled the field of stability of molybdate (or tungstate) systems of alkaline transuranic - mobybdates (or tungstates) to be clarified. 3) The study of the structural properties of the identified phases. These results taken as a whole made it possible to establish a ''comparative crystal - chemistry'' of the oxigenated phases of Np, Pu and Am with those of the thorium and uranium actinide elements and with the rare earths of adjacent ionic radius. 4) The Moessbauer resonance study of 237 Np in the solid solution Usub(1-x)Npsub(x)O 2 (0 [fr

  15. Study of the number of neutrons produced by fission of 239Pu

    International Nuclear Information System (INIS)

    Jacob, M.

    1958-01-01

    Study of the number of neutrons produced by fission of 239 Pu. The counting by coincidence of fissions and neutrons produced by these fissions allows the study of the variation of the mean number of neutrons emitted by ν fission. In the first chapter, it studied the variation of the mean number of neutrons emitted by 239 Pu fission with the energy of the incident neutron. A description of the experiment is given: a spectrometer with a crystal of sodium chloride or beryllium (mounted on a goniometer) is used, a fission chamber containing 10 mg of 239 Pu and the neutron detection system constituted of BF 3 counters which are enriched in 10 B. In the second part, the counting by coincidence of fissions and neutrons produced by the same fission and received by two different groups of counters allow the determination of a relationship between the root mean square and the average of neutron number produced by fission. The variation of the mean number of neutrons emitted by fission of 239 Pu is studied when we change from a thermal spectra of neutrons to a fission spectra of incident neutrons. Finally, when separating in two different part the fission chamber, it is possible to measure the mean number of neutrons emitted from fission of two different sources. It compared the mean number of neutrons emitted by fission of 239 Pu and 233 U. (M.P.)

  16. Comparison of Pu isotopic composition between gamma and mass spectrometry: Experience from IAEA-SAL

    International Nuclear Information System (INIS)

    Parus, J.L.; Raab, W.

    1998-01-01

    About 2000 Pu containing samples have been analysed during the last 8 years at SAL using gamma spectrometry (GS) in parallel with mass spectrometry (MS). Four different detectors have been used for the measurement of gamma-ray spectra and several versions of the MGA program have been used for spectra evaluation. The results of Pu isotopic composition obtained by both methods have neem systematically compared. Attempts to improve the agreement between GS and MS are described. This was done by adjustment of the emission probabilities for some gamma energies and the development of a new correlation equation for 242 Pu. These improvements have been applied for evaluation of two sets containing 320 and 404 samples, respectively analysed in 1991 and in 1992-93. The mean differences and their standard deviations between MS and GS were calculated, showing mean relative differences for 238-241 Pu isotopes in the range from 0.1 to 0.5% with standard deviations within ± 0.4 to ±1%. For 242 Pu these values are about 0.5% and ± 5%, respectively. (author)

  17. Insights into reactive scattering of Pu + H2 at low energies

    Science.gov (United States)

    Gao, Cong-Zhang; Wu, Yong; Liu, Ling; Wang, Pei; Wang, Jian-Guo

    2017-08-01

    The corrosion of metal interfaces, due to continuous exposure to gaseous hydrogen atmosphere, significantly limits the applications of plutonium-based nuclear materials in the related fields. In this work, we simplify the situations by considering the fundamental reactions of Pu atom with a single H2 molecule, and investigate from a theoretical perspective collision dynamics of Pu + H2 at low energies (0.2 \\text{eV}\\text{--}13 \\text{eV}) based on ab initio potential energy surfaces. Trajectory calculation analysis shows that three main channels, the formation of the PuH2, the PuH fragment, and the fragmentation, exhibit different energy-dependent cross sections, from which we observed that the PuH2 formation is non-threshold reaction, whereas the other two channels are featured by pronounced threshold effects, which is in consistent with experimental observations. In addition, we find that three-body effects can play a decisive role in the reactions since the simplified Morse potential energy surfaces can even yield spurious results in some situations.

  18. The Distribution of 239Pu in the Surface Soils at the Ujung Lemahabang Area

    International Nuclear Information System (INIS)

    Tarigan, Cerdas

    2000-01-01

    The study distribution of 239 Pu in the surface soil at the Ujung Lemahabang Area has been carried out. The aim of study to get information about 239 Pu activity in the depth of soil at 0 - 5 cm. 5 - 10 cm, 10 - 15 cm, 15 - 20 cm and 20 - 25 cm respectively. Sampling was done at random from 3 stations amount 1 kg respectively. The analytical method used was decomposition and leaching process using acid, chemical purification with anion exchange resin and measurement of activity with a spectrometry Result of the measurement showed that the average 239 Pu activity was 10.16 mBq/kg and this method was very good because its have high recovery of separation about 80 %. The activity of 239 Pu was lower than the result of measurement in another location in the world. The result of the study showed that the possibility of 239 Pu came from natural and fallout from atmospheric nuclear tests in the last period 1950 - 1960. (author)

  19. PuReMD-GPU: A reactive molecular dynamics simulation package for GPUs

    International Nuclear Information System (INIS)

    Kylasa, S.B.; Aktulga, H.M.; Grama, A.Y.

    2014-01-01

    We present an efficient and highly accurate GP-GPU implementation of our community code, PuReMD, for reactive molecular dynamics simulations using the ReaxFF force field. PuReMD and its incorporation into LAMMPS (Reax/C) is used by a large number of research groups worldwide for simulating diverse systems ranging from biomembranes to explosives (RDX) at atomistic level of detail. The sub-femtosecond time-steps associated with ReaxFF strongly motivate significant improvements to per-timestep simulation time through effective use of GPUs. This paper presents, in detail, the design and implementation of PuReMD-GPU, which enables ReaxFF simulations on GPUs, as well as various performance optimization techniques we developed to obtain high performance on state-of-the-art hardware. Comprehensive experiments on model systems (bulk water and amorphous silica) are presented to quantify the performance improvements achieved by PuReMD-GPU and to verify its accuracy. In particular, our experiments show up to 16× improvement in runtime compared to our highly optimized CPU-only single-core ReaxFF implementation. PuReMD-GPU is a unique production code, and is currently available on request from the authors

  20. PuReMD-GPU: A reactive molecular dynamics simulation package for GPUs

    Energy Technology Data Exchange (ETDEWEB)

    Kylasa, S.B., E-mail: skylasa@purdue.edu [Department of Elec. and Comp. Eng., Purdue University, West Lafayette, IN 47907 (United States); Aktulga, H.M., E-mail: hmaktulga@lbl.gov [Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, MS 50F-1650, Berkeley, CA 94720 (United States); Grama, A.Y., E-mail: ayg@cs.purdue.edu [Department of Computer Science, Purdue University, West Lafayette, IN 47907 (United States)

    2014-09-01

    We present an efficient and highly accurate GP-GPU implementation of our community code, PuReMD, for reactive molecular dynamics simulations using the ReaxFF force field. PuReMD and its incorporation into LAMMPS (Reax/C) is used by a large number of research groups worldwide for simulating diverse systems ranging from biomembranes to explosives (RDX) at atomistic level of detail. The sub-femtosecond time-steps associated with ReaxFF strongly motivate significant improvements to per-timestep simulation time through effective use of GPUs. This paper presents, in detail, the design and implementation of PuReMD-GPU, which enables ReaxFF simulations on GPUs, as well as various performance optimization techniques we developed to obtain high performance on state-of-the-art hardware. Comprehensive experiments on model systems (bulk water and amorphous silica) are presented to quantify the performance improvements achieved by PuReMD-GPU and to verify its accuracy. In particular, our experiments show up to 16× improvement in runtime compared to our highly optimized CPU-only single-core ReaxFF implementation. PuReMD-GPU is a unique production code, and is currently available on request from the authors.

  1. Identifying and localizing network problems using the PuNDIT project

    International Nuclear Information System (INIS)

    Batista, Jorge; McKee, Shawn; Dovrolis, Constantine; Lee, Danny

    2015-01-01

    In today's world of distributed collaborations of scientists, there are many challenges to providing effective infrastructures to couple these groups of scientists with their shared computing and storage resources. The Pythia Network Diagnostic InfrasTructure (PuNDIT[1]) project is integrating and scaling research tools and creating robust code suitable for operational needs addressing the difficult challenge of automating the detection and location of network problems.PuNDIT is building upon the de-facto standard perfSONAR[2] network measurement infrastructure deployed in Open Science Grid(OSG)[3] and the Worldwide LHC Computing Grid(WLCG)[4]to gather and analyze complex real-world network topologies coupled with their corresponding network metrics to identify possible signatures of network problems from a set of symptoms. The PuNDIT Team is working closely with the perfSONAR developers from ESnet and Internet2 to integrate PuNDIT components as part of the perfSONAR Toolkit. A primary goal for PuNDIT is to convert complex network metrics into easily understood diagnoses in an automated way. We will report on the project progress to-date in working with the OSG and WLCG communities, describe the current implementation including some initial results and discuss future plans and the project timeline. (paper)

  2. Extension of 239+240Pu sediment geochronology to coarse-grained marine sediments

    Science.gov (United States)

    Kuehl, Steven A.; Ketterer, Michael E.; Miselis, Jennifer L.

    2012-01-01

    Sediment geochronology of coastal sedimentary environments dominated by sand has been extremely limited because concentrations of natural and bomb-fallout radionuclides are often below the limit of measurement using standard techniques. ICP-MS analyses of 239+240Pu from two sites representative of traditionally challenging (i.e., low concentration) environments provide a "proof of concept" and demonstrate a new application for bomb-fallout radiotracers in the study of sandy shelf-seabed dynamics. A kasten core from the New Zealand shelf in the Southern Hemisphere (low fallout), and a vibracore from the sandy nearshore of North Carolina (low particle surface area) both reveal measurable 239+240Pu activities at depth. In the case of the New Zealand site, independently verified steady-state sedimentation results in a 239+240Pu profile that mimics the expected atmospheric fallout. The depth profile of 239+240Pu in the North Carolina core is more uniform, indicating significant sediment resuspension, which would be expected in this energetic nearshore environment. This study, for the first time, demonstrates the utility of 239+240Pu in the study of sandy environments, significantly extending the application of bomb-fallout isotopes to coarse-grained sediments, which compose the majority of nearshore regions.

  3. Calorimetric study of the intermetallic compounds UAl2 and PuAl2

    International Nuclear Information System (INIS)

    Trainor, R.J.; Brodsky, M.B.; Knapp, G.S.

    1975-01-01

    Results of low temperature specific heat measurements are presented on the strongly paramagnetic intermetallic compounds UAl 2 and PuAl 2 in the temperature intervals 0.9 to 20 0 K, respectively. These compounds are characterized by very narrow 5f bands near the Fermi energy. The low-temperature properties of UAl 2 and PuAl 2 are dominated by long lived spin fluctuations within these narrow bands. In UAl 2 a nearly field-independent T 3 logT contribution dominates the specific heat below 10 0 K, consistent with the predictions of ferromagnetic spin-fluctuation theory. The specific heat, static susceptibility, and electrical resistivity are mutually consistent with T/sub sf/ = 25 +- 10 0 K, where T/sub sf/ is the characteristic spin-fluctuation temperature of the system. Below 20 0 K, the specific heat of PuAl 2 contains a very large linear term, C greater than or approximately equal to 260T (mJ/mole- 0 K), which is approximately four times the magnitude of the measured susceptibility, when both quantities are expressed in the same units. The specific heat of PuAl 2 exhibits no anomalous behavior below 10 0 K, where a resistivity anomaly has been previously obser []ed. The properties of PuAl 2 are qualitatively discussed in terms of antiferromagnetic spin fluctuations. (auth)

  4. Kinetics of the high temperature oxygen exchange reaction on 238PuO2 powder

    International Nuclear Information System (INIS)

    Whiting, Christofer E.; Du, Miting; Felker, L. Kevin; Wham, Robert M.; Barklay, Chadwick D.; Kramer, Daniel P.

    2015-01-01

    Oxygen exchange reactions performed on PuO 2 suggest the reaction is influenced by at least three mechanisms: an internal chemical reaction, surface mobility of active species/defects, and surface exchange of gaseous oxygen with lattice oxygen. Activation energies for the surface mobility and internal chemical reaction are presented. Determining which mechanism is dominant appears to be a complex function including at least specific surface area and temperature. Thermal exposure may also impact the oxygen exchange reaction by causing reductions in the specific surface area of PuO 2 . Previous CeO 2 surrogate studies exhibit similar behavior, confirming that CeO 2 is a good qualitative surrogate for PuO 2 , in regards to the oxygen exchange reaction. Comparison of results presented here with previous work on the PuO 2 oxygen exchange reaction allows complexities in the previous work to be explained. These explanations allowed new conclusions to be drawn, many of which confirm the conclusions presented here. - Highlights: • PuO 2 Oxygen exchange kinetics can be influenced by at least 3 different mechanisms. • An internal chemical reaction controls the rate at high temperature and large SSA. • Surface mobility and surface exchange influence rate at lower temperatures and SSA. • Exchange temperatures may alter SSA and make data difficult to interpret.

  5. Thermophysical properties of solid and liquid pure and alloyed Pu: A review

    Energy Technology Data Exchange (ETDEWEB)

    Boivineau, M., E-mail: michel.boivineau@cea.f [CEA, Centre de Valduc, Departement de Recherches sur les Materiaux Nucleaires, F-21120 Is-sur-Tille (France)

    2009-08-01

    The thermophysical properties of both solid and liquid pure and alloyed plutonium have been investigated up to 4000 K by use of a resistive pulse heating technique, the so-called isobaric expansion experiment (IEX). Electrical resistivity, specific volume (density), latent heats of transformations, heat of fusion have been measured and extended in the whole liquid region. Additional static measurements have been also performed in order to determine the heat transport properties such as heat capacity, thermal diffusivity and thermal conductivity of plutonium alloys. After a first part devoted to additional results on pure Pu under rapid heating, this paper mostly deals with studies on different delta-stabilized Pu alloys in the high temperature range, particularly in the liquid state which is the principal originality of this work. In addition to the thermophysical data mentioned above, an attention is also paid onto sound velocity measurements on these alloys in the solid and liquid states. Hence, an anomalous behavior such as elastic softening is confirmed in the delta phase as already reported previously. Moreover, sound velocity and equation of state parameters (adiabatic and thermal bulk moduli, Grueneisen parameter, and specific heats ratio) have been investigated on liquid alloyed Pu. Such results confirm previous works on liquid pure Pu by presenting an atypical dual behavior of sound velocity, and are discussed in terms of delocalization process of the 5f electrons of both liquid pure and alloyed Pu.

  6. Incidence of brain tumours in rats exposed to an aerosol of 239PuO2

    International Nuclear Information System (INIS)

    Sanders, C.L.; Dagle, G.E.; Mahaffey, J.A.

    1992-01-01

    Incidence of brain tumours was investigated in 3390 female and male Wistar rats exposed to an aerosol of 239 PuO 2 , or as sham-exposed controls. Lung doses ranged from 0.05 to 22 Gy. In females, six brain tumours were found in 1058 control rats (incidence, 0.6%) and 24 brain tumours in 2134 rats exposed to Pu (incidence, 1.1%); the survival-adjusted level of significance was p = 0.29 for comparing control with exposed females. In males, two brain tumours were found in 60 control rats (incidence, 3.3%) and seven brain tumours in 138 rats exposed to Pu (incidence, 5.1%); the survival-adjusted level of significance was p = 0.33. Brain tumour incidence was about five times greater in male than in female rats (p = 0.0001), a highly significant sex difference in brain tumour incidence. Tumour types were distributed similarly among control and Pu-exposed groups of both sexes; most were astrocytomas. Mean lifespans for rats with brain tumours were not significantly different between control and Pu-exposed rats. (author)

  7. Designing of Multiphase Fly Ash/MWCNT/PU Composite Sheet Against Electromagnetic Environmental Pollution

    Science.gov (United States)

    Gujral, Parth; Varshney, Swati; Dhawan, S. K.

    2016-06-01

    Fly ash and multiwalled carbon nanotubes (MWCNT) reinforced multiphase polyurethane (PU) composite sheets have been fabricated by using a solution casting technique. Utilization of fly ash was the prime objective in order to reduce environmental pollution and to enhance the shielding properties of PU polymer. Our study proves that fly ash particles with MWCNTs in a PU matrix leads to novel hybrid high performance electromagnetic shielding interference material. Scanning electron microscopy confirms the existence of fly ash particles along with MWCNTs in a PU matrix. This multiphase composite shows total shielding effectiveness of 35.8 dB (>99.99% attenuation) in the Ku-band (12.4-18 GHz) frequency range. This is attributed to high dielectric losses of reinforcement present in the polymers matrix. The Nicolson-Ross-Weir algorithm has been applied to calculate the electromagnetic attributes and dielectric parameters of the PU samples by using scattering parameters ( S 11, S 22, S 12, S 21). The synthesized multiphase composites were further characterized by using x-ray diffraction, Fourier transform infrared spectroscopy, and thermo gravimetric analysis.

  8. Importance of resonance parameters of fertile nuclei and of 239Pu isotope for fast power reactors

    International Nuclear Information System (INIS)

    Barre, J.Y.; Khairallah, A.

    1975-01-01

    The importance of resonance parameters of fertile nuclei and of 239 Pu isotope for fast power reactors will be restricted, in this presentation, to mixed oxide-uranium-plutonium fuelled sodium-cooled and uranium-oxide-sodium reflected fast reactors. The power range lies between 200 and 2000 MWe. Among the topics of this specialist meeting, the isotopes to be considered are, primarly 239 Pu then 238 U and 240 Pu. Resonance parameters are mainly used in fast power reactor calculations through the well-known concept of self shielding factors. After a short description of the determination and the use of these self-shielding factors, their sensitivities to resonance parameters are characterized from some specific examples: those sensitivities are small. Then, the main design parameters sensitive to the amplitude of self-shielding factors are considered: critical enrichment, global breeding gain. The relative importance of isotope, reaction rate and energy range are mentionned. In a third part, the Doppler effect, sensitive to the temperature variation of self-shielding factors, is considered in the same way. Finally, it is concluded that the present knowledge of resonance parameters for 238 U, 239 Pu and 240 Pu is sufficient for fast power reactors from a designer point of view [fr

  9. Thermophysical properties and oxygen transport in (Thx,Pu1−x)O2

    Science.gov (United States)

    Galvin, C. O. T.; Cooper, M. W. D.; Rushton, M. J. D.; Grimes, R. W.

    2016-01-01

    Using Molecular Dynamics, this paper investigates the thermophysical properties and oxygen transport of (Thx,Pu1−x)O2 (0 ≤ x ≤ 1) between 300–3500 K. In particular, the superionic transition is investigated and viewed via the thermal dependence of lattice parameter, linear thermal expansion coefficient, enthalpy and specific heat at constant pressure. Oxygen diffusivity and activation enthalpy are also investigated. Below the superionic temperature an increase of oxygen diffusivity for certain compositions of (Thx,Pu1−x)O2 compared to the pure end members is predicted. Oxygen defect formation enthalpies are also examined, as they underpin the superionic transition temperature and the increase in oxygen diffusivity. The increase in oxygen diffusivity for (Thx,Pu1−x)O2 is explained in terms of lower oxygen defect formation enthalpies for (Thx,Pu1−x)O2 than PuO2 and ThO2, while links are drawn between the superionic transition temperature and oxygen Frenkel disorder. PMID:27796314

  10. Thermophysical properties and oxygen transport in (Thx,Pu1-x)O2.

    Science.gov (United States)

    Galvin, C O T; Cooper, M W D; Rushton, M J D; Grimes, R W

    2016-10-31

    Using Molecular Dynamics, this paper investigates the thermophysical properties and oxygen transport of (Th x ,Pu 1-x )O 2 (0 ≤ x ≤ 1) between 300-3500 K. In particular, the superionic transition is investigated and viewed via the thermal dependence of lattice parameter, linear thermal expansion coefficient, enthalpy and specific heat at constant pressure. Oxygen diffusivity and activation enthalpy are also investigated. Below the superionic temperature an increase of oxygen diffusivity for certain compositions of (Th x ,Pu 1-x )O 2 compared to the pure end members is predicted. Oxygen defect formation enthalpies are also examined, as they underpin the superionic transition temperature and the increase in oxygen diffusivity. The increase in oxygen diffusivity for (Th x ,Pu 1-x )O 2 is explained in terms of lower oxygen defect formation enthalpies for (Th x ,Pu 1-x )O 2 than PuO 2 and ThO 2 , while links are drawn between the superionic transition temperature and oxygen Frenkel disorder.

  11. Mechanism of the rapid dissolution of Pu02 under oxidizing conditions and applications

    International Nuclear Information System (INIS)

    Madic, C.; Lecomte, M.; Bourges, J.; Koehly, G.

    1991-01-01

    Until the recent years, plutonium dioxide was known to be among the metallic oxides the most difficult to dissolve. From thermodynamic calculations it can be predicted that PuO 2 will dissolve under oxidizing conditions. This can be achieved using Ag(II) species possibly regenerated by electrochemical means. The mechanism of such a process has been elucidated using carbon paste electrochemistry and 18 O labelling. These studies demonstrate that the chemical reaction limiting the overall proces is located on the surface of the solid PuO 2 , and that the first step consists in the oxidation of the plutonium into Pu(V) species. Applications of the dissolution process of PuO 2 by electrogenerated Ag(II) were growing in the recent years in FRANCE. These applications developed often in collaboration with SGN and COGEMA, concern the treatment of: out of specifications PuO 2 , incineration ashes, wastes produced during MOX fuel fabrication, and during the dismantling of old nuclear facilities. A general overview of these different applications is given

  12. Comparison and modification of Pu-239 kinetics in young and adult rats

    International Nuclear Information System (INIS)

    Volf, V.; Gamer, A.; Laengle, U.

    1987-01-01

    It is obvious that the biokinetics of bone-seeking radionuclides are influenced by skeletal growth and remodelling, the rate of which in general decreases with increasing age. For plutonium, Mahlum and Sikov (1974) observed that rats injected with Pu-239 as weanlings retained a lower percentage in the liver and more in the bones than the animals injected as adults. However, skeletal Pu-239 was diluted more rapidly in the young rats because of intensive new bone formation and this led to a more pronounced reduction in the accumulation of radiation dose than was the case in adult animals. The aim of the present experiments was to study: a) The age effect on Pu-239 biokinetics in adult rates as influenced by the sex of the animals. b) Early retention and distribution of Pu-239 in the bones of young and adult rats injected with an optimal osteosarcomogenic dose. c) The effectiveness of a delayed prolonged administration of Zn-DTPA in drinking water for the mobilization of injected Pu-239 in rats of various age. 3 refs.; 5 figs.; 1 table

  13. Application of extraction paper chromatography in the analysis of Pu in aqueous samples containing 241Am

    International Nuclear Information System (INIS)

    Jagasia, Poonam; Dhami, P.S.; Tripathi, S.C.; Gandhi, P.M.

    2015-01-01

    Closing the fuel cycle is an inevitable option for sustained growth and is hallmark of Indian Atomic Energy Programme. Analysis of fissile component especially plutonium is very important for almost all the process streams at the back end of the fuel cycle. Among the various Isotopes of plutonium, 241 Pu is β emitter and decays to 241 Am (T 1/2 of ∼432 y) which is an α emitter and having γ energy of ∼60 keV. Its specific activity is about 56 times higher than that Pu. Therefore, Pu stream is always associated with 241 Am and its activity increases with time needing its separation prior to radiometric assay. Among the various separation techniques, solvent extraction method employing thenoytrifluoroacetone (TTA) is commonly employed for its selective separation under particular experimental conditions. In an alternate approach, 2-ethyl hexyl 2-ethyl hexyl phosphonic acid (KSM-17) based extraction paper chromatography (EPC) was attempted for separation of 241 Am from plutonium prior to radiometry. Pu 4+ forms strong complex with KSM-17 and is held at the point of application whereas 241 Am migrates towards the solvent front under the experimental conditions. During migration clear separation is observed in ∼15 minutes using 0.5 M HNO 3 as developing reagent. After separation is achieved, 1 cm 2 spot area containing Pu is desorbed in 1 mL xylene phase and used for radiometric counting

  14. Fuel-pellet-fabrication experience using direct-denitration-recycle-PuO2-coprecipitated mixed oxide

    International Nuclear Information System (INIS)

    Rasmussen, D.E.; Schaus, P.S.

    1980-01-01

    The fuel pellet fabrication experience described in this paper involved three different feed powders: coprecipitated PuO 2 -UO 2 which was flash calcined in a fluidized bed; co-direct denitrated PuO 2 -UO 2 ; and direct denitrated LWR recycle PuO 2 which was mechanically blended with natural UO 2 . The objectives of this paper are twofold; first, to demonstrate that acceptable quality fuel pellets were fabricated using feed powders manufactured by processes other than the conventional oxalate process; and second, to highlight some pellet fabrication difficulties experienced with the direct denitration LWR recycle PuO 2 feed material, which did not produce acceptable pellets. The direct denitration LWR recycle PuO 2 was available as a by-product and was not specifically produced for use in fuel pellet fabrication. Nevertheless, its characteristics and pellet fabrication behavior serve to re-emphasize the importance of continued process development involving both powder suppliers and fuel fabricators to close the fuel cycle in the future

  15. The toxicity of inhaled particles of 238PuO2 in dogs

    International Nuclear Information System (INIS)

    Muggenburg, B.A.; Guilmette, R.A.; Griffith, W.C. Jr.; Hahn, F.F.; Boecker, B.B.

    1991-01-01

    This study was conducted to determine the toxicity of inhaled 238 PuO 2 in the dog. Inhalation was selected because it is the mostly likely route of human exposure in the event of an accidental airborne release. Of 166 dog in the study, 72 inhaled 1.5μm and 72 inhaled 3.0 μm activity median aerodynamic diameter particles of 238 PuO 2 . Another 24 dogs inhaled the aerosol vector without plutonium. The aerosol exposures resulted in initial pulmonary burdens ranging from 37 to 0.11 and 55.5 to 0.37 kBq of 238 Pu/kg body mass, of 1.5 μm and 3.0 μ, particles, respectively. The particles dissolved slowly resulting in translocation of the Pu to liver, bone and other sites. The dogs were observed for biological effects over their life span. Necropsies were performed at death, and tissues were examined microscopically. The principal late-occurring effects were tumors of the lung, skeleton, and liver. Risk factors estimated for these cancers were 2800 lung cancers/10 4 Gy, 800 liver cancers/10 4 Gy, and 6200 bone cancers/10 4 Gy for dogs. The potential hazard from 238 Pu to humans may include tumors of the lung, bone and liver because of the likelihood of similarity of the dose patterns for the two species. 10 refs., 1 fig., 3 tabs

  16. Rapid determination of 239Pu in urine samples using molecular recognition technology product AnaLigRPu-02 gel

    International Nuclear Information System (INIS)

    Silvia Dulanska; Boris Remenec; Jan Bilohuscin; Miroslav Labaska; Bianka Horvathova; Andrej Matel

    2013-01-01

    This paper describes the use of IBC's AnaLig R Pu-02 molecular recognition technology product to effectively and selectively pre-concentrate, separate and recover plutonium from urine samples. This method uses two-stage column separations consisting of two different commercial products, Eichrom's Pre-filter Material and AnaLig R Pu-02 resin from IBC Advanced Technologies. By eliminating the co-precipitation techniques and the ashing steps to remove residual organics, the analysis time was reduced significantly. The method was successfully tested by adding known activities of reference solutions of 242 Pu and 239 Pu to urine samples. (author)

  17. Investigation on the formation of a third phase in the extraction of Pu(IV) nitrate with tributyl phosphate

    International Nuclear Information System (INIS)

    Yu Enjiang; Liu Liming; Huang Huaian

    1986-01-01

    The formation of a third phase is studied in the system Pu(IV) nitratenitric acid-TBP-alkane diluent (or kerosine). The maximum concentration (solubility, S Pu ) of Pu(IV) in the equilibrium organic phase at which still no third phase is formed is measured as a function of the nitric acid concentration in the equilibrium aqueous phase C H , the temperature, and the molecular size of n-alkane duluent. Results show that maxima of S Pu at 6 to 7 M nitric acid are observed at 17 deg C, 26 deg C and 35 deg C while not at 40 deg C. Minima on the S Pu vs. C H curves at 0.5 to 2 M mitric acid have been observed at 17 deg C and 26 deg C. It is found that the molecular size of n-alkane diluents has a very pronounced effect on S Pu . The effect of aqueous equilibrium Pu(IV) concentration on the formation of a third phase is investigated, when the equilibrium HNO 3 concentration is 3.5 M. It is shown that the plutonium concentration of the third phase is increased with increasing aqueous equilibrium Pu(IV) concentration. The effect of the addition of lauryl alcohol on the S Pu is preliminarily studied

  18. Activity ratios of {sup 137}Cs, {sup 90}Sr and {sup 239+240}Pu in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Bossew, P. [European Commission - DG Joint Research Centre, Institute for Environment and Sustainability (IES), I-21020 Ispra (Vatican City State, Holy See,) (Italy)], E-mail: peter.bossew@jrc.it; Lettner, H. [Institute of Physics and Biophysics, University of Salzburg, Hellbrunner Strasse 34, A-5020 Salzburg (Austria)], E-mail: herbert.lettner@sbg.ac.at; Hubmer, A.; Erlinger, C.; Gastberger, M. [Institute of Physics and Biophysics, University of Salzburg, Hellbrunner Strasse 34, A-5020 Salzburg (Austria)

    2007-09-15

    Both global and Chernobyl fallout have resulted in environmental contamination with radionuclides such as {sup 137}Cs, {sup 90}Sr and {sup 239+240}Pu. In environmental samples, {sup 137}Cs and {sup 239+240}Pu can be divided into the contributions of either source, if also the isotopes {sup 134}Cs and {sup 238}Pu are measurable, based on the known isotopic ratios in global and Chernobyl fallout. No analogous method is available for {sup 90}Sr. The activity ratios of Sr to Cs and Pu, respectively, are known for the actual fallout mainly from air filter measurements; but due to the high mobility of Sr in the environment, compared to Cs and Pu, these ratios generally do not hold for the inventory many years after deposition. In this paper we suggest a method to identify the mean contributions of global and Chernobyl fallout to total Sr in soil, sediment and cryoconite samples from Alpine and pre-Alpine regions of Austria, based on a statistical evaluation of Sr/Cs/Pu radionuclide activity ratios. Results are given for Sr:Cs, Sr:Pu and Cs:Pu ratios. Comparison with fallout data shows a strong depletion of Sr against Cs and Pu.

  19. Determination of 241Pu in nuclear waste slurries: a comparative study using LSC and ICP-MS.

    Science.gov (United States)

    Jäggi, M; Röllin, S; Alvarado, J A Corcho; Eikenberg, J

    2012-02-01

    (241)Pu was determined in slurry samples from a nuclear reactor decommissioning project at the Paul Scherrer Institute (Switzerland). To validate the results, the (241)Pu activities of five samples were determined by LSC (TriCarb and Quantulus) and ICP-MS, with each instrument at a different laboratory. In lack of certified reference materials for (241)Pu, the methods were further validated using the (241)Pu information values of two reference sediments (IAEA-300 and IAEA-384). Excellent agreement with the results was found between LSC and ICP-MS in the nuclear waste slurries and the reference sediments. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Calculations of thermodynamic properties of PuO{sub 2} by the first-principles and lattice vibration

    Energy Technology Data Exchange (ETDEWEB)

    Minamoto, Satoshi [Energy and Industrial Systems Department, ITOCHU Techno-Solutions Corporation, Kasumigaseki 3-chome, Chiyoda-ku, Tokyo 100-6080 (Japan)], E-mail: satoshi.minamoto@ctc-g.co.jp; Kato, Masato [Japan Atomic Energy Agency, 4-33 Muramatsu, Tokai-mura, Naka-gun, Ibaraki 319-1194 (Japan); Konashi, Kenji [Institute for Materials Research, Tohoku University, 2145-2 Narita-chou, Oarai-chou, Ibaraki 311-1313 (Japan); Kawazoe, Yoshiyuki [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

    2009-03-15

    Plutonium dioxide (PuO{sub 2}) is a key compound of mixed oxide fuel (MOX fuel). To predict the thermal properties of PuO{sub 2} at high temperature, it is important to understand the properties of MOX fuel. In this study, thermodynamic properties of PuO{sub 2} were evaluated by coupling of first-principles and lattice dynamics calculation. Cohesive energy was estimated from first-principles calculations, and the contribution of lattice vibration to total energy was evaluated by phonon calculations. Thermodynamic properties such as volume thermal expansion, bulk modulus and specific heat of PuO{sub 2} were investigated up to 1500 K.