Certified reference material for radionuclides in fish flesh sample IAEA-414 (mixed fish from the Irish Sea and North Sea)

International Nuclear Information System (INIS)

Pham, M.K.; Sanchez-Cabeza, J.A.; Povinec, P.P.; Arnold, D.; Benmansour, M.; Bojanowski, R.; Carvalho, F.P.; Kim, C.K.; Esposito, M.; Gastaud, J.; Gasco, C.L.; Ham, G.J.; Hegde, A.G.; Holm, E.; Jaskierowicz, D.; Kanisch, G.; Llaurado, M.; La Rosa, J.; Lee, S.-H.; Liong Wee Kwong, L.; Le Petit, G.; Maruo, Y.; Nielsen, S.P.; Oh, J.-S.; Oregioni, B.; Palomares, J.; Pettersson, H.B.L.; Rulik, P.; Ryan, T.P.; Sato, K.; Schikowski, J.; Skwarzec, B.; Smedley, P.A.; Tarjan, S.; Vajda, N.; Wyse, E.

2006-01-01

A certified reference material (CRM) for radionuclides in fish sample IAEA-414 (mixed fish from the Irish Sea and North Seas) is described and the results of the certification process are presented. Nine radionuclides ( 4 K, 137 Cs, 232 Th, 234 U, 235 U, 238 U, 238 Pu, 239+24 Pu and 241 Am) were certified for this material. Information on massic activities with 95% confidence intervals is given for six other radionuclides ( 9 Sr, 21 Pb( 21 Po), 226 Ra, 239 Pu, 24 Pu 241 Pu). Less frequently reported radionuclides ( 99 Tc, 129 I, 228 Th, 23 Th and 237 Np) and information on some activity and mass ratios are also included. The CRM can be used for quality assurance/quality control of the analysis of radionuclides in fish sample, for the development and validation of analytical methods and for training purposes. The material is available from IAEA, Vienna, in 100 g units

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.

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)

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)

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.

Reference material manufacture and certification for the AVNG

Energy Technology Data Exchange (ETDEWEB)

Hauck, Danielle K [Los Alamos National Laboratory; Thron, Jonathan [Los Alamos National Laboratory; MacArthur, Duncan W. [Los Alamos National Laboratory; Livke, Alexander [RFNC - VNIIEF; Bulatov, M [RFNC-VNIIEF; Kondratov, Sergey [RFNC-VNIIEF; Leplyavkina, M [RFNC-VNIIEF; Razinkov, Sergey [RFNC-VNIIEF; Sivachev, D [RFNC-VNIIEF; Tsybryaev, S [RFNC-VNIIEF; V' yushin, A [RFNC-VNIIEF

2010-07-09

Testing and demonstration of any radiation measurement system requires the use of appropriate radioactive sources. An attribute measurement system (A VNG) was developed and fabricated at the Russian Federal Nuclear Center, VNIIEF, Russia, under contract with LANL, USA. The A VNG detects neutron and gamma radiation signatures and compares the data analysis results with the specified threshold values for three unclassified attributes; plutonium is present or absent, plutonium mass is greater than or less than the specified threshold value and plutonium isotopic ratio ²⁴⁰Pu to ²³⁹Pu) is greater than or less then the threshold value. A set of reference materials (RMs) was specially manufactured for the A VNG with masses and isotopic ratios above and below the selected thresholds. The set of RMs was certified in compliance with the Russian metrological requirements. The RMs were used to debug and test the A VNG and to demonstrate the A VNG operation to an American delegation in June 2009. In this presentation, we will describe the various steps in the manufacture and certification of these RM sources.

Reference material manufacture and certification for the AVNG

Energy Technology Data Exchange (ETDEWEB)

Hauck, Danielle K [Los Alamos National Laboratory; Mac Arthur, Duncan [Los Alamos National Laboratory; Thron, Jonathan L [Los Alamos National Laboratory; Livke, Alexander [VNIIEF; Kondratov, Sergey [VNIIEF; Razinkov, Sergey [VNIIEF

2010-01-01

Testing and demonstration of any radiation measurement system requires the use of appropriate radioactive sources. The AVNG implementation that we describe is an attribute measurement system built by RFNC - VNIIEF in Sarov, Russia. The AVNG detects neutron and gamma radiation signatures and displays the three unclassified attributes of 'plutonium presence,' 'plutonium mass > 2 kg,' and 'plutonium isotopic ratio ({sup 240}Pu to {sup 239}Pu) < 0.1.' The AVNG was tested using a number of reference material (RM) sources with masses and isotopic ratios above and below these thresholds. The AVNG was demonstrated in June 2009 using several of these sources in addition to detector calibration sources. Since the AVNG was designed to measure multi-kg plutonium sources, the RM was manufactured specifically for use with this system. In addition, the RM was used to test the thresholds in the AVNG, so the size and composition of each RM was certified prior to use. In this presentation, we will describe the various steps in the manufacture and certification of these RM sources.

Reference material manufacture and certification for the AVNG

International Nuclear Information System (INIS)

2010-01-01

Testing and demonstration of any radiation measurement system requires the use of appropriate radioactive sources. An attribute measurement system (A VNG) was developed and fabricated at the Russian Federal Nuclear Center, VNIIEF, Russia, under contract with LANL, USA. The A VNG detects neutron and gamma radiation signatures and compares the data analysis results with the specified threshold values for three unclassified attributes; plutonium is present or absent, plutonium mass is greater than or less than the specified threshold value and plutonium isotopic ratio 240 Pu to 239 Pu) is greater than or less then the threshold value. A set of reference materials (RMs) was specially manufactured for the A VNG with masses and isotopic ratios above and below the selected thresholds. The set of RMs was certified in compliance with the Russian metrological requirements. The RMs were used to debug and test the A VNG and to demonstrate the A VNG operation to an American delegation in June 2009. In this presentation, we will describe the various steps in the manufacture and certification of these RM sources.

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...

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

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?

Reference materials and interlaboratory comparison for actinide analysis

International Nuclear Information System (INIS)

Hanssens, Alain; Viallesoubranne, Carole; Roche, Claude; Liozon, Gerard

2008-01-01

Measurement quality is crucial for the safety of nuclear facilities and is a primary requirement for fissile material monitoring and accountancy. CETAMA (Cea Committee for the establishment of analysis methods), in collaboration with Cea and AREVA laboratories, fabricates certified reference materials and organizes interlaboratory comparison programs for plutonium and uranium assay in solution. A new plutonium metal measurement standard (MP3) is currently being prepared by Cea and is a subject of cooperative work in view of its certification and use by analysis laboratories. U and Pu interlaboratory comparisons are carried out at regular intervals on benchmark samples in coordination with working groups from French nuclear laboratories. These programs are supported by international cooperation. 'Chemical' methods (potentiometry, gravimetric analysis, etc.) generally provide the best accuracy. Coulometry is the benchmark technique for plutonium assay: its metrological qualities should be an incentive for wider use by laboratories performing precise control assays of plutonium as well as uranium. Gravimetric analysis provides excellent results for analysis of pure uranyl nitrate solutions. In view of its many advantages we encourage laboratories to employ this technique to assay pure U or Pu solutions. 'Physical' or 'physicochemical' methods are increasingly used, and their performance has improved. K-edge absorption spectrometry and isotope dilution mass spectrometry are capable of reaching measurement quality levels comparable to those of the best 'chemical' methods. (authors)

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

Determination of {sup 241}Pu in nuclear waste slurries: A comparative study using LSC and ICP-MS

Energy Technology Data Exchange (ETDEWEB)

Jaeggi, M., E-mail: maya.jaeggi@psi.ch [Department Logistics for Radiation Safety and Security, Radioanalytics, CH-5232 Villligen PSI (Switzerland); Roellin, S., E-mail: Stefan.Roellin@babs.admin.ch [Federal Office for Civil Protection, SPIEZ Laboratory, CH-3700 Spiez (Switzerland); Corcho Alvarado, J.A., E-mail: Corcho-Alvarado@chuv.ch [Institute of Radiation Physics, University Hospital and University of Lausanne, Rue du Grand-Pre 1, 1007 Lausanne (Switzerland); Eikenberg, J., E-mail: jost.eikenberg@psi.ch [Department Logistics for Radiation Safety and Security, Radioanalytics, CH-5232 Villligen PSI (Switzerland)

2012-02-15

{sup 241}Pu was determined in slurry samples from a nuclear reactor decommissioning project at the Paul Scherrer Institute (Switzerland). To validate the results, the {sup 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 {sup 241}Pu, the methods were further validated using the {sup 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. - Highlights: Black-Right-Pointing-Pointer Good agreement between the {sup 241}Pu activity of 5 slurry samples, using 3 measurement techniques. Black-Right-Pointing-Pointer {sup 241}Pu information values of two IAEA samples agreed well for the 3 measurement techniques. Black-Right-Pointing-Pointer Low detection limits were achieved; 1.8 Bq/kg (Quantulus), 2 Bq/kg (ICP-MS) and 3.5 Bq/kg (TriCarb).

High-Quality Medium-Resolution Gamma-Ray Spectra from Certified Reference Uranium and Plutonium Materials

International Nuclear Information System (INIS)

Zsigrai, J.; Muehleisen, A.; ); Weber, A.-L.; Funk, P.; Berlizov, A.; Mintcheva, J.

2015-01-01

The Institute of Transuranium Elements (ITU) has made an effort to record a collection of medium resolution gamma-ray spectra from well-characterized U and Pu certified reference materials CRM-171 (also known as SRM-969), CBNM-271, and Harwell PIDIE standards. The goal of this exercise was twofold: (i) to complement the international database of reference gamma-ray spectra with high-quality data for medium resolution spectrometers, and (ii) to feed Phase I of the U/Pu isotopic inter-comparison exercise that is being jointly organized by the ESARDA NDA Working Group and IAEA. Phase II of the exercise will be fed by similar spectra recorded by Institute for Radiological Protection and Nuclear Safety (IRSN). These activities are supported through a joint Member State Support Programmes (MSSP) task and aimed at delivering reliable methodologies for the determination of U/Pu isotopic composition using medium resolution gamma-spectrometers. The latter have obvious benefits for in-field applications, amongst which are better usability, portability and maintainability. As the spectra will be made available online for software developers and end users, ultimately this will also contribute to sustainability as well as the improved and validated performance of existing U/Pu isotopic codes. The spectra were recorded using the IAEA's standard Lanthanum Bromide (LaBr3(Ce)) (2.0'' x 0.5'') and Cadmium Zink Telluride (CdZnTe) (500 mm''3) detectors and acquisition electronics. Aiming to acquire the highest quality reference data, the spectra were measured for long acquisition times, ensuring very good counting statistics across potentially useful spectral intervals — up to 1 MeV for the CdZnTe and up to 2.6 MeV for the LaBr3(Ce) detectors. Great attention was also paid to ensure that the measurement geometry was stable and reproducible, and the spectra had minimum influence from background radiation and pile-up effects. The paper will briefly

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.

Reference materials and interlaboratory comparison for actinide analysis

Energy Technology Data Exchange (ETDEWEB)

Hanssens, Alain; Viallesoubranne, Carole; Roche, Claude; Liozon, Gerard [Commissariat a l' Energie Atomique, Marcoule: BP 17171, 30207 Bagnols sur Ceze (France)

2008-07-01

Measurement quality is crucial for the safety of nuclear facilities and is a primary requirement for fissile material monitoring and accountancy. CETAMA (Cea Committee for the establishment of analysis methods), in collaboration with Cea and AREVA laboratories, fabricates certified reference materials and organizes interlaboratory comparison programs for plutonium and uranium assay in solution. A new plutonium metal measurement standard (MP3) is currently being prepared by Cea and is a subject of cooperative work in view of its certification and use by analysis laboratories. U and Pu interlaboratory comparisons are carried out at regular intervals on benchmark samples in coordination with working groups from French nuclear laboratories. These programs are supported by international cooperation. 'Chemical' methods (potentiometry, gravimetric analysis, etc.) generally provide the best accuracy. Coulometry is the benchmark technique for plutonium assay: its metrological qualities should be an incentive for wider use by laboratories performing precise control assays of plutonium as well as uranium. Gravimetric analysis provides excellent results for analysis of pure uranyl nitrate solutions. In view of its many advantages we encourage laboratories to employ this technique to assay pure U or Pu solutions. 'Physical' or 'physicochemical' methods are increasingly used, and their performance has improved. K-edge absorption spectrometry and isotope dilution mass spectrometry are capable of reaching measurement quality levels comparable to those of the best 'chemical' methods. (authors)

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.

Safety Analysis Report: Packages, Pu oxide and Am oxide shipping cask: Packaging of fissile and other radioactive materials: Final report

International Nuclear Information System (INIS)

Chalfant, G.G.

1984-12-01

The PuO 2 cask or 5320-3 cask is designed for shipment of americium or plutonium by surface transportation modes. The cask design was physically tested to demonstrate that it met the criteria specified in US ERDA Manual Chapter 0529, dated 12/21/76, which invokes Title 10 Code of Federal Regulations, Part 71 (10 CFR 71) ''Packaging of Radioactive Materials for Transport,'' and Title 49 CFR Parts 171.179 ''Hazardous Materials Regulations.'' (US DOE Order 4580.1A, Chapter III, superseded manual chapter 0529 effective May 1981, but it retained the same 10 CFR 71 and 49 CFR 171-179 references

Certified reference material for radionuclides in fish flesh sample IAEA-414 (mixed fish from the Irish Sea and North Sea)

DEFF Research Database (Denmark)

Pham, M.K.; Sanchez-Cabeza, J.A.; Povinec, P.P.

2006-01-01

A certified reference material (CRM) for radionuclides in fish sample IAEA-414 (mixed fish from the Irish Sea and North Seas) is described and the results of the certification process are presented. Nine radionuclides (K-40, Cs-137, Th-232, U-234, U-235, U-238, Pu-238, Pu239+240 and Am-241) were...... ratios are also included. The CRM can be used for quality assurance/quality control of the analysis of radionuclides in fish sample, for the development and validation of analytical methods and for training purposes. The material is available from IAEA, Vienna, in 100 g units. (c) 2006 Elsevier Ltd. All...

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

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.)

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)

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

Uranium reference materials

International Nuclear Information System (INIS)

Donivan, S.; Chessmore, R.

1987-07-01

The Technical Measurements Center has prepared uranium mill tailings reference materials for use by remedial action contractors and cognizant federal and state agencies. Four materials were prepared with varying concentrations of radionuclides, using three tailings materials and a river-bottom soil diluent. All materials were ground, dried, and blended thoroughly to ensure homogeneity. The analyses on which the recommended values for nuclides in the reference materials are based were performed, using independent methods, by the UNC Geotech (UNC) Chemistry Laboratory, Grand Junction, Colorado, and by C.W. Sill (Sill), Idaho National Engineering Laboratory, Idaho Falls, Idaho. Several statistical tests were performed on the analytical data to characterize the reference materials. Results of these tests reveal that the four reference materials are homogeneous and that no large systematic bias exists between the analytical methods used by Sill and those used by TMC. The average values for radionuclides of the two data sets, representing an unbiased estimate, were used as the recommended values for concentrations of nuclides in the reference materials. The recommended concentrations of radionuclides in the four reference materials are provided. Use of these reference materials will aid in providing uniform standardization among measurements made by remedial action contractors. 11 refs., 9 tabs

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.

Decontamination of soils and materials containing medium-fired PuO{sub 2} using inhibited fluorides with polymer filtration technology

Energy Technology Data Exchange (ETDEWEB)

Temer, D.J.; Villarreal, R.; Smith, B.F. [Los Alamos National Lab., NM (United States)

1997-10-01

The decontamination of soils and/or materials from medium-fired plutonium oxide (PuO{sub 2}) with an effective and efficient decontamination agent that will not significantly dissolve the matrix requires a new and innovative technology. After testing several decontamination agents and solutions for dissolution of medium-fired PuO{sub 2}, the most successful decontamination solutions were fluoride compounds, which were effective in breaking the Pu-oxide bond but would not extensively dissolve soil constituents and other materials. The fluoride compounds, tetra fluoboric acid (HBF{sub 4}) and hydrofluorosilicic acid (H{sub 2}F{sub 6}Si), were effective in dissolving medium-fired PuO{sub 2}, and did not seem to have the potential to dissolve the matrix. In both compounds, the fluoride atom is attached to a boron or silicon atom that inhibits the reactivity of the fluoride towards other compounds or materials containing atoms less attracted to the fluoride atom in an acid solution. Because of this inhibition of the reactivity of the fluoride ion, these compounds are termed inhibited fluoride compounds or agents. Both inhibited fluorides studied effectively dissolved medium-fired PuO{sub 2} but exhibited a tendency to not attack stainless steel or soil. The basis for selecting inhibited fluorides was confirmed during leaching tests of medium-fired PuO{sub 2} spiked into soil taken from the Idaho National Engineering Laboratory (INEL). When dissolved in dilute HNO{sub 3}, HCl, or HBr, both inhibited fluoride compounds were effective at solubilizing the medium-fired PuO{sub 2} from spiked INEL soil.

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)

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)

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

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

IAEA biological reference materials

International Nuclear Information System (INIS)

Parr, R.M.; Schelenz, R.; Ballestra, S.

1988-01-01

The Analytical Quality Control Services programme of the IAEA encompasses a wide variety of intercomparisons and reference materials. This paper reviews only those aspects of the subject having to do with biological reference materials. The 1988 programme foresees 13 new intercomparison exercises, one for major, minor and trace elements, five for radionuclides, and seven for stable isotopes. Twenty-two natural matrix biological reference materials are available: twelve for major, minor and trace elements, six for radionuclides, and four for chlorinated hydrocarbons. Seven new intercomparisons and reference materials are in preparation or under active consideration. Guidelines on the correct use of reference materials are being prepared for publication in 1989 in consultation with other major international producers and users of biological reference materials. The IAEA database on available reference materials is being updated and expanded in scope, and a new publication is planned for 1989. (orig.)

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

The diffusion coefficient for 239Pu, 241Am, 99Tc and 137Cs in highly compacted buffer materials

International Nuclear Information System (INIS)

Zhou Kanghan; Li Guoding

1998-01-01

Based on one-dimension diffusion model, the diffusion coefficients of Pu, Am, Tc and Cs in highly compacted sodium-bentonite generally used as buffer materials in geologic disposal system for high-level radioactive waste have been determined at room temperature in the atmosphere of nitrogen. The results show that the diffusion coefficients of Am, Pu and Tc and about 10 -13 ∼10 -15 m 2 /s, and that of Cs about 10 -12 m 2 /s. The diffusion coefficients of these elements decrease with the increasing of the dry density of buffer materials. From the relationship of diffusion coefficient, retardation coefficient and dry density of bentonite, it has been concluded that Am and Pu transfer predominately by diffusion in solid phase, however, Cs and Tc by diffusion in pore water

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)

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

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.

Quality control provisions applied in the preparation and characterization of Pu-bearing PERLA standards

International Nuclear Information System (INIS)

Guardini, S.; Guzzi, G.; Mousty, F.; Kuhn, E.; Regge, P. de

1990-01-01

This report describes the work carried out at the different laboratories where Pu-bearing samples, intended for use as reference materials for NDA measurements, were prepared and characterized. The standard samples were produced from PuO2 and MOX batches of different nature and are at present stored in the PERLA facility at the Institute for Safety Technology of the JRC Ispra and are available for use. Particular attention is paid to the quality control procedures adopted during the sampling, preparation and analysis of the material, to fulfil the requirements established a priori for NDA standards to be used in Safeguards. The results of the different quality control checks are presented and discussed. The drawings of the containers for the PuO2 and MOX powders and of the special fuel rods for MOX pellets are also presented. This report is intended for use in conjunction with the PERLA STANDARD CERTIFICATES which are issued for each type of material considered, and gives to the user the possibility of tracing all analytical data back to primary standards

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)

NDA PDP Program PuO2 increased particle size specification and design

International Nuclear Information System (INIS)

Marshall, R.S.; Taggart, D.P.; Becker, G.K.; Woon, W.Y.

1996-01-01

Provisions in the National TRU Program Quality Assurance Program Plan require an assessment of performance for nondestructive waste assay (NDA) systems employed in the program. This requirement is in part fulfilled through the use of Performance Demonstration programs. In order to optimize the quality and quantity of information acquired during a given Performance Demonstration Program cycle, the assessment employed is to be carefully specified and designed. The assessment must yield measurement system performance data meaningful with respect to NDA system capability to accommodate attributes of interest known to occur in actual waste forms. The design and specification of the increased particle size PuO 2 PDP working reference materials (WRMs) is directed at providing a straightforward mechanism to assess waste NDA system capability to account for biases introduced by large PuO 2 particles. The increased particle size PuO 2 PDP WRM design addresses actual waste form attributes associated with PuO 2 particle size and distributions thereof, the issue of a known and stable WRM configuration and equally important appropriate certification and tractability considerations

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.

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

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....

Preparation and evaluation of reference materials for accountancy analysis. (2) Evaluation results

International Nuclear Information System (INIS)

Sumi, Mika; Abe, Katsuo; Kageyama, Tomio; Nakazawa, Hiroaki; Takamatsu, Mai; Kacchi, Tomokazu; Murakami, Toshiki; Ai, Hironobu

2009-01-01

Destructive analysis for accountancy at nuclear fuel facilities should attain international target values for measurement uncertainties in safeguarding nuclear materials (ITVs). Since measurement uncertainties of isotope dilution mass spectrometry depend on uncertainties of spikes (standard materials) used, utilizing highly reliable standard material is essential. The LSD spikes prepared under collaboration work with JAEA and JNFL has different Pu/U ratio and smaller nuclear material in a spike compared with the LSD spikes used a safeguard laboratories, and the value of Pu which separated and purified from MOX and used as raw material for one of the LSD spike prepared at JAEA were measured at JAEA. Uncertainties of the prepared LSD spikes and the measurement results of actual samples with these LSD spikes were evaluated based on ISO-GUM and compared with ITVs. (author)

Production of NDA Working Reference Materials for the Capability Evaluation Project

International Nuclear Information System (INIS)

Noll, P.D. Jr.; Marshall, R.S.

1998-01-01

The production of Non Destructive Assay (NDA) Working Reference Materials (WRMs) that are traceable to nationally recognized standards was undertaken to support implementation of the Idaho National Engineering and Environmental Laboratory (INEEL) Nondestructive Waste Assay Capability Evaluation Project (CEP). The WRMs produced for the CEP project consist of Increased Am/Pu mass ration (IAP) and depleted Uranium (DU) WRMs. The CEP IAP/DU WRM set provides radioactive material standards for use in combination with 55 gallon drum waste matrix surrogates for the assessment of waste NDA assay system performance. The Production of WRMs is a meticulous process that is not without certain trials and tribulations. Problems may arise at any of the various stages of WRM production which include, but are not limited to; material characterization (physical, chemical, and isotopic), material blend parameters, personnel radiation exposure, gas generation phenomenon, traceability to national standards, encapsulation, statistical evaluation of the data, and others. Presented here is an overall description of the process by which the CEP WRMs were produced and certified as well as discussions pertaining to some of the problems encountered and how they were solved

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

Proposal for Analysis of the Safeguarded Nuclear Materials 235U and 239Pu by Delayed Neutrons Technique

International Nuclear Information System (INIS)

El-Mongy, S.A.

2000-01-01

This paper introduces, describes and initiates a very sensitive and rapid non-destructive technique to be used for analysis of the safeguarded nuclear materials 235 U and 239 Pu. The technique is based on fission of the nuclear material by neutrons and then measuring the delayed neutrons produced from the neutron rich fission products. By this technique, fissile isotope content ( 235 U) can be determined in the presence of the other fissile (e.g. 239 Pu) or fertile isotopes (e.g. 238 U) in fresh and spent fuel. The time consumed for analysis of bulk materials by this technique is only 4 minutes. The method is also used for analysis of uranium in rock, sediment, soil, meteorites, lunar, biological, urine, archaeological, zircon sand and seawater samples. The method enables uranium in a sample to be measured without respect to its oxidation state, organic and inorganic elements

Surrogate measurement of the 238Pu(n,f) cross section

International Nuclear Information System (INIS)

Ressler, J. J.; Burke, J. T.; Escher, J. E.; Bernstein, L. A.; Bleuel, D. L.; Casperson, R. J.; Gostic, J.; Henderson, R.; Scielzo, N. D.; Thompson, I. J.; Wiedeking, M.; Angell, C. T.; Goldblum, B. L.; Munson, J.; Basunia, M. S.; Phair, L. W.; Beausang, C. W.; Hughes, R. O.; Hatarik, R.; Ross, T. J.

2011-01-01

The neutron-induced fission cross section of 238 Pu was determined using the surrogate ratio method. The (n,f) cross section over an equivalent neutron energy range 5-20 MeV was deduced from inelastic α-induced fission reactions on 239 Pu, with 235 U(α,α ' f) and 236 U(α,α ' f) used as references. These reference reactions reflect 234 U(n,f) and 235 U(n,f) yields, respectively. The deduced 238 Pu(n,f) cross section agrees well with standard data libraries up to ∼10 MeV, although larger values are seen at higher energies. The difference at higher energies is less than 20%.

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

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

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

{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

Production and Evaluation of 236gNp and Reference Materials for Naturally Occurring Radioactive Materials

Science.gov (United States)

Larijani, Cyrus Kouroush

This thesis is based on the development of a radiochemical separation scheme capable of separating both 236gNp and 236Pu from a uranium target of natural isotopic composition ( 1 g uranium) and 200 MBq of fission decay products. The isobaric distribution of fission residues produced following the bombardment of a natural uranium target with a beam of 25 MeV protons has been evaluated. Decay analysis of thirteen isobarically distinct fission residues were carried out using high-resolution gamma-ray spectrometry at the UK National Physical Laboratory. Stoichiometric abundances were calculated via the determination of absolute activity concentrations associated with the longest-lived members of each isobaric chain. This technique was validated by computational modelling of likely sequential decay processes through an isobaric decay chain. The results were largely in agreement with previously published values for neutron bombardments on natural uranium at energies of 14 MeV. Higher relative yields of products with mass numbers A 110-130 were found, consistent with the increasing yield of these radionuclides as the bombarding energy is increased. Using literature values for the production cross-section for fusion of protons with uranium targets, it is estimated that an upper limit of approximately 250 Bq of activity from the 236Np ground state was produced in this experiment. Using a radiochemical separation scheme, Np and Pu fractions were separated from the produced fission decay products, with analyses of the target-based final reaction products made using Inductively Couple Plasma Mass Spectrometry (ICP-MS) and high-resolution alpha and gamma-ray spectrometry. In a separate research theme, reliable measurement of Naturally Occurring Radioactive Materials is of significance in order to comply with environmental regulations and for radiological protection purposes. The thesis describes the standardisation of three reference materials, namely Sand, Tuff and TiO2 which

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)

Preparation and evaluation of reference materials for accountancy analysis. (1) Preparation and evaluation method

International Nuclear Information System (INIS)

Takamatsu, Mai; Kacchi, Tomokazu; Murakami, Toshiki; Ai, Hironobu; Sumi, Mika; Abe, Katsuo; Kageyama, Tomio; Nakazawa, Hiroaki

2009-01-01

Isotope dilution mass spectrometry method used for the accountancy analysis at nuclear fuel facilities requires the standard materials called LSD (Large Size Dried) spike. Generally, LSD spikes are prepared from certified reference materials (CRMs) which supplied from foreign laboratories. However, the difficulty of Pu CRM importation is increasing. It is important for safeguards to attain and continue high reliable accountancy analysis and stable securing of LSD spike is essential. Therefore, in order to conserve CRMs, several types of LSD spike were prepared under collaboration work between JAEA and JNFL, such as the amount of nuclear material in one LSD spike is decreased and others. Practical test with actual samples were performed at JNFL Rokkasho reprocessing plant, and those results were compared with the results obtained by using LSD spike which supplied from foreign laboratory. Preparation and verification analysis of LSD spikes and evaluation of uncertainty based on ISO-GUM will be presented. (author)

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

Survey of reference materials. V. 2: Environmentally related reference materials for trace elements, nuclides and microcontaminants

International Nuclear Information System (INIS)

1996-05-01

The present report presently contains over 250 reference materials with trace element and organic contaminant information on fuel, geological and mineral, anthropogenic disposal, soil reference and miscellaneous reference materials. Not included in the current report is information on most biological and environmental reference materials with trace element, stable isotope, radioisotope and organic contaminant information. 8 refs, tabs

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

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)

Efforts to save 244Pu in Mark 18A targets for use in international safeguards measurements

International Nuclear Information System (INIS)

Goldberg, Steven A.; Cappis, John; Clarke, Stephanie; Whitesel, Robert

2001-01-01

Full text: The Office of Arms Control and Nonproliferation and the Office of Security and Emergency Operations are working collaboratively to evaluate the disposition of a large quantity of the 244 Pu isotope contained in 65 Mark ISA targets at the Savannah River Site (SRS). 244 Pu is used as a standard reference material for plutonium analytical measurements required for both domestic and international safeguards. 244 Pu is particularly valuable for high accuracy measurements of plutonium in small samples containing trace quantities of plutonium (environmental analysis) and for measurements of material through-put in bulk processing facilities handling large volumes of plutonium and plutonium-bearing materials. In October 2000, an assessment team was tasked by the U.S. Department of Energy (DOE) Under Secretary to evaluate pathways and costs for the chemical separation and isotopic enrichment of the 244 Pu identified in the targets. Even though the target materials have recently been designated as a National Resource, they are scheduled for waste disposal unless funds can be identified and assigned to the project. Background information on the Mark ISA targets and a review of the assessment process are presented below to inform other organizations and governments of current efforts to examine potential disposition options and to solicit international cooperation for the extraction of the 244 Pu. Background - The United States possesses the bulk of the world's supply of the rare isotope 244 Pu. This isotope was produced by extremely long neutron irradiation of 242 Pu in a high-flux reactor during experiments used primarily to create isotopes of medical interest. In its separated enriched form, 244 Pu is regarded as the most accurate and desirable spike for safeguards, forensics, and environmental analysis of plutonium, allowing the simultaneous measurement of a sample for isotopic abundances and elemental concentration. Such measurements are a critical component of

Reference materials and representative test materials: the nanotechnology case

International Nuclear Information System (INIS)

Roebben, G.; Rasmussen, K.; Kestens, V.; Linsinger, T. P. J.; Rauscher, H.; Emons, H.; Stamm, H.

2013-01-01

An increasing number of chemical, physical and biological tests are performed on manufactured nanomaterials for scientific and regulatory purposes. Existing test guidelines and measurement methods are not always directly applicable to or relevant for nanomaterials. Therefore, it is necessary to verify the use of the existing methods with nanomaterials, thereby identifying where modifications are needed, and where new methods need to be developed and validated. Efforts for verification, development and validation of methods as well as quality assurance of (routine) test results significantly benefit from the availability of suitable test and reference materials. This paper provides an overview of the existing types of reference materials and introduces a new class of test materials for which the term ‘representative test material’ is proposed. The three generic concepts of certified reference material, reference material(non-certified) and representative test material constitute a comprehensive system of benchmarks that can be used by all measurement and testing communities, regardless of their specific discipline. This paper illustrates this system with examples from the field of nanomaterials, including reference materials and representative test materials developed at the European Commission’s Joint Research Centre, in particular at the Institute for Reference Materials and Measurements (IRMM), and at the Institute for Health and Consumer Protection (IHCP).

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.

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

Safety analysis report: packages 238Pu oxide shipping cask (packaging of fissile and other radioactive materials). Final report

International Nuclear Information System (INIS)

Evans, J.E.; Gates, A.A.

1975-06-01

Plutonium-238 (as PuO 2 powder) is shipped in triple-container stainless steel shipping casks in compliance with ERDA Manual Chapter 0529 (ERDAM 0529), Safety Standards for the Packaging of Fissile and Other Radioactive Materials. (U.S.)

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

COMAR - database for certified reference materials

International Nuclear Information System (INIS)

Klich, H.; Caliste, J.P.

1988-01-01

With more than 130 producers of reference materials (RM) throughout the world, it is often difficult to find the best reference material for a specific application. The computer database COMAR has been developed to aid chemists in finding the needed reference material. (orig.)

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.

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)

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)

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.

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

[The molecular composition and spectral properties of polysaccharide isolated from pu-erh tea and its material].

Science.gov (United States)

Gong, Jia-shun; Hu, Xiao-jing; Peng, Chun-xiu; Zhou, Hong-jie

2010-07-01

Pu-erh tea, a kind of well-known tea from the ancient time, is originally produced in the Yunnan Lanchan River basin through a special solid state fermentation by fungi. It uses sun-dried green tea as its starting materials. To investigate the variation of composition and spectral properties of polysaccharide during solid state fermentation of pu-erh tea by using Saccharomyces cerevisiae as preponderant starter and using sun-dried green tea as materials in the present study. The results showed that the content of water soluble polysaccharide was increased, and the activity of hydrolase such as cellulase, pectinase and glucomylase were also enhanced. The content of neutral sugar increased with the ferment time increasing and the M(w) of raw polysaccharide showed significant difference during fermentation. The main polysaccharide TPS2 and TPS1 were isolated and purified from pu-erh tea and its materials by DEAE-52 and Sephadex G-150 column chromatography. TPS2 contains the higher content of uronic acid, but TPS1 contains the higher contents of neutral sugar and protein. Monosaccharide analysis by GC-MS revealed that TPS1 and TPS2 were composed of arabinose, galactose, glucose, rhamnose, xylose and mannose with molar ratios of 24.2 : 23.6 : 5.9 : 3.2 : 1.8 : 1.1 and 19.3 : 26.9 : 3.2 : 2.7 : 1.3 : 5.5, respectively. The average molecular weight of TPS1 and TPS2 was 1.68 x 10(4) and 1.21 x 10(4) Daltons, respectively. UV scanning spectrum showed that TPS1 and TPS2 had no characteristic absorption between 200 and 400 nm wavelength, it suggested that they contain trace protein. IR spectrum of TPS1 and TPS2 demonstrated that pyranoid rings were contained in them. As shown in the image of atomic force microscope, the molecular appearance of TPS1 and TPS2 resembled islands and apparently consisted of conglomerations. The height of conglomerations of TPS2 was about 40 nm and the length or width was 0.5-0.8 microm, while the height of conglomerations of TPS1 was about 4nm and

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.

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)

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.

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)

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)

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

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.

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...

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.

Safety analysis report: packages. Pu oxide and Am oxide shipping cask (Packaging of fissile and other radioactive materials). Final report

International Nuclear Information System (INIS)

Chalfant, G.G.

1980-05-01

The PuO 2 cask or SP 5320-2 and 3 cask is designed for surface shipment of americium or plutonium. The cask design was physically tested to demonstrate that it met the criteria specified in US ERDA Manual Chapter 0529, and Chapter I, Interstate Commerce Commission. The package has been assessed for transport of up to 357 grams of plutonium (403 grams PuO 2 powder) and up to 176 grams of americium (200 grams AmO 2 powder), having a maximum decay heat of 203 watts. Criticality evaluation alone would allow the shipment as Fissile Class II but the radiation level of the cask, measured at the time of shipment, may exceed 50 mrem/h at the surface and require shipment as Fissile Class III. Sample calculations address only the more restrictive of the two materials, which in most cases is 238 PuO 2

A routine chromium determination in biological materials; application to various reference materials and standard reference materials

International Nuclear Information System (INIS)

Tjioe, P.S.; Goeij, J.J.M. de; Volkers, K.J.

1979-01-01

The determination limit under standard working conditions of chromium in biological materials is discussed. Neutron activation analysis and atomic spectrometry have been described for some analytical experiences with NBS SRM 1577 reference material. The chromium determination is a part of a larger multi-element scheme for the determination of 12 elements in biological materials

Vertical distribution of Pu radionuclides, 241Am and 99Sr in soil Samples from Romania

International Nuclear Information System (INIS)

Breban, D.; Mocanu, N.; Moreno-Bermudez, J.

2002-01-01

The investigated area is a natural alpine pasture located in the South chain of the Carpathian Mountains, which was found as one of the most contaminated areas in Romania after the Chernobyl accident.Radioactive concentrations of Pu radioisotopes, 2 41Am and 9 0Sr were determined in successive layers from 4 soil sections downward a depth of 6-8 cm, providing for the first time information on the effect of fallout acumulation of these radionuclides in soil samples from Romania. Pu and Am were separated by using a combined sequential procedure based on anion exchange and extraction chromatography. The measurements of 241Pu were performed by Liquid Scintillation Counting. 9 0Sr was determined by chemical separation of Sr using the classical precipitation method and Cerenkov counting of 9 0Y. For Quality Control IAEA reference materials were analyzed along with the samples. In a soil section of 8 cm depth radioactive inventories were approximately 500 Bq/m 2 for 2 41Pu, 115 Bq/m 2 for 2 39 +2 40Pu, 8 Bq/m 2 for 2 38Pu, 50 Bq/m2 for 2 41Am and 2500 Bq/m 2 for 9 0Sr. The data on each of the radioisotopes vertical distribution profile are compared between themselves and give an idea for their migration. On the basis of activity isotopic ratios in the soil depth profile, the origin of the contamination (Chernobyl accident and nuclear weapon test fallout) is discussed. The results are also compared to previous data on Cs-137

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

Preparation of plant-specific NDA reference material

International Nuclear Information System (INIS)

Abedin-Zadeh, R.; Beetle, T.; Kuhn, E.; Terrey, D.; Turel, S.; Busca, G.; Guardini, S.

1983-01-01

The importance of having suitable and well characterized non-destructive assay (NDA) reference materials for the verification activities of the safeguards control authorities is stressed. The Euratom Inspectorate and the IAEA have initiated an extensive programme for the procurement and preparation of Joint Euratom/IAEA safeguards NDA reference materials with the active participation of the Ispra Establishment of the Euratom Joint Research Centre. The different type and nature of materials, condition of measurements, and plant characteristics and provisions had to be taken into account for plant-specific NDA reference materials. The preparation of each reference material was planned case by case and specific criteria such as limitations in different facilities, measurement capabilities, conditions, product availability and population variability are being ascertained. A procurement scheme was prepared describing step-by-step procedures detailing responsibilities, measurement conditions, destructive analysis schemes, desired characteristics and methods of data evaluation. This paper describes the principles and procedures carried out for the preparation of a reference MOX pin, low enriched uranium reference rods, low enriched uranium reference drums, reference MTR assemblies, and THTR reference pebbles. The scheme for each characterization technique is presented. (author)

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.)

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

NBS activities in biological reference materials

Energy Technology Data Exchange (ETDEWEB)

Rasberry, S.D.

1988-12-01

NBS activities in biological reference materials during 1986-1988 are described with a preview of plans for future certifications of reference materials. During the period, work has been completed or partially completed on about 40 reference materials of importance to health, nutrition, and environmental quality. Some of the reference materials that have been completed during the period and are described include: creatinine (SRM 914a), bovine serum albumin (SRM 927a), cholesterol in human serum (SRM's 1951-1952), aspartate aminotransferase (RM 8430), cholesterol and fat-soluble vitamins in coconut oil (SRM 1563), wheat flour (SRM 1567a), rice flour (SRM 1568a), mixed diet (RM 8431a), dinitropyrene isomers and 1-nitropyrene (SRM 1596), and complex PAH's from coal tar (SRM 1597). Oyster tissue (SRM 1566a) is being analyzed and should be available in 1988.

Reference material systems: a sourcebook for material assessment

Energy Technology Data Exchange (ETDEWEB)

Bhagat, N. (ed.)

1976-12-01

A reference set of data related to material systems and a framework for carrying out the material technologies assessment are presented. While the bulk of renewables have been considered in this report, the nonrenewable materials dealt with here include structural materials only, such as steel, aluminum, cement and concrete, and bricks. The complete data set is supposed to include material flows, energy requirements, capital and labor inputs, and environmental effects for each process that a resource must go through to become a useful material for an end use. Although effort has been made to obtain as much information as possible, considerable gaps in data, apparent throughout this report, could not be avoided. A new material technology can be evaluated by substituting that technology for appropriate elements of the reference materials system and calculating the net change in material resource, energy, capital and labor requirements, and environmental impacts. This combination of information thus serves as a means of evaluating the potential benefits to be gained by research in various material technologies.

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.

U.S. N.R.C. special safeguards study on nuclear material control and accounting

International Nuclear Information System (INIS)

Smith, G.D.

1976-01-01

In Feb. 1975, NRC directed that an effort be made to determine a safeguards program for Pu recycle. This paper summarizes results of individual contractor evaluations of upgrading material control and accounting concepts as applied to strategically important special nuclear material and describes staff interpretations of these results as applied to future high-throughput fuel-cycle facilities. Real-time material control, design for physical inventory, Pu isotopics control and calorimetry, and material control and accounting for highly enriched uranium fuel materials were the concepts studied. 1 table, 15 references

15 CFR 230.3 - New Standard Reference Materials.

Science.gov (United States)

2010-01-01

... NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE STANDARD REFERENCE MATERIALS STANDARD REFERENCE MATERIALS General Information § 230.3 New Standard Reference Materials. When new SRM's... scientific and trade journals. ...

The urgent requirement for new radioanalytical certified reference materials for nuclear safeguards, forensics, and consequence management

International Nuclear Information System (INIS)

Inn, K.G.W.; Martin Johnson, Jr.C.; Warren Oldham; Lav Tandon; Simon Jerome; Thomas Schaaff; Robert Jones; Daniel Mackney; Pam MacKill; Brett Palmer

2013-01-01

A multi-agency workshop was held from 25 to 27 August 2009, at the National Institute of Standards and Technology (NIST), to identify and prioritize the development of radioanalytical Certified Reference Materials (CRMs, generally provided by National Metrology Institutes; Standard Reference Materials, a CRM issued by NIST) for field and laboratory nuclear measurement methods to be used to assess the consequences of a domestic or international nuclear event. Without these CRMs, policy makers concerned with detecting proliferation and trafficking of nuclear materials, attribution and retribution following a nuclear event, and public health consequences of a nuclear event would have difficulty making decisions based on analytical data that would stand up to scientific, public, and judicial scrutiny. The workshop concentrated on three areas: post-incident Improvised Nuclear Device (IND) nuclear forensics, safeguard materials characterization, and consequence management for an IND or a Radiological Dispersion Device detonation scenario. The workshop identified specific CRM requirements to fulfill the needs for these three measurement communities. Of highest priority are: (1) isotope dilution mass spectrometry standards, specifically 233 U, 236 gNp, 244 Pu, and 243 Am, used for quantitative analysis of the respective elements that are in critically short supply and in urgent need of replenishment and certification; (2) CRMs that are urgently needed for post-detonation debris analysis of actinides and fission fragments, and (3) CRMs used for destructive and nondestructive analyses for safeguards measurements, and radioisotopes of interest in environmental matrices. (author)

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

The field migration tests of 237Np, 238Pu, 241Am and 90Sr in aerated loess, aquifer and engineering barrier materials

International Nuclear Information System (INIS)

Li Shushen; Wang Zhiming; Zhao Yingjie; Fan Zhiwen; Liu Chunli; An Yongfeng; Yang Yue'e; Wu Qinghua

2003-01-01

This paper introduces the field migration tests of 237 Np, 238 Pu, 241 Am and 90 Sr in aerated loess, aquifer and engineering barrier materials. The tests in the aerated loess and engineering barrier materials were carried out under both natural and artificial sprinkling (15 mm/d) conditions. The tests in aquifer were carried out in both assemblies packed with undisturbed aquifer media and a definite undisturbed area. The results indicate that after 3 years tests no significant migrations were seen for all nuclides in engineering barrier materials under two kinds of conditions and in aerated loess under natural conditions. For the aerated loess under artificial sprinkling conditions, 2.7 cm (center of mass) migration in the area directly below the sand tracer layer (named as area 1) and 13 cm (peak) migration in the area outside the area 1 for 90 Sr were observed; There was no migration for 237 Np, 238 Pu and 241 Am. It was discovered that the sand layer used as carrier of nuclide tracer has barrier effect on unsaturated water and an influence on nuclide migration. This has been demonstrated by the inter comparison experiment with both sand and loess as tracer carrier. In the tracer tests of undisturbed aquifer area there was no significant migration of 237 Np, 238 Pu, 241 Am and 90 Sr after 1023 days. In the assembly 8 there was no significant migration for 238 Pu and 241 Am and a small backward migration 0.95 cm for 237 Np and 4.7 cm migration (center of mass) for 90 Sr were observed. The tests also indicate that there is no significant difference of nuclide migration in ordinary and degraded cement

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

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.)

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.

Value assignment of nutrient concentrations in five standard reference materials and six reference materials.

Science.gov (United States)

Sharpless, K E; Gill, L M

2000-01-01

A number of food-matrix reference materials (RMs) are available from the National Institute of Standards and Technology (NIST) and from Agriculture Canada through NIST. Most of these materials were originally value-assigned for their elemental composition (major, minor, and trace elements), but no additional nutritional information was provided. Two of the materials were certified for selected organic constituents. Ten of these materials (Standard Reference Material [SRM] 1,563 Cholesterol and Fat-Soluble Vitamins in Coconut Oil [Natural and Fortified], SRM 1,566b Oyster Tissue, SRM 1,570a Spinach Leaves, SRM 1,974a Organics in Mussel Tissue (Mytilus edulis), RM 8,415 Whole Egg Powder, RM 8,418 Wheat Gluten, RM 8,432 Corn Starch, RM 8,433 Corn Bran, RM 8,435 Whole Milk Powder, and RM 8,436 Durum Wheat Flour) were recently distributed by NIST to 4 laboratories with expertise in food analysis for the measurement of proximates (solids, fat, protein, etc.), calories, and total dietary fiber, as appropriate. SRM 1846 Infant Formula was distributed as a quality control sample for the proximates and for analysis for individual fatty acids. Two of the materials (Whole Egg Powder and Whole Milk Powder) were distributed in an earlier interlaboratory comparison exercise in which they were analyzed for several vitamins. Value assignment of analyte concentrations in these 11 SRMs and RMs, based on analyses by the collaborating laboratories, is described in this paper. These materials are intended primarily for validation of analytical methods for the measurement of nutrients in foods of similar composition (based on AOAC INTERNATIONAL's fat-protein-carbohydrate triangle). They may also be used as "primary control materials" in the value assignment of in-house control materials of similar composition. The addition of proximate information for 10 existing reference materials means that RMs are now available from NIST with assigned values for proximates in 6 of the 9 sectors of

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

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

Importance of 241 Am Determination in the Characterization of PuO2 Standards for Calorimetric Assay.

Energy Technology Data Exchange (ETDEWEB)

Sampson, Thomas E.

2005-01-01

Plutonium dioxide (PuO{sub 2}) standards are often used both as heat standards and isotopic standards for calorimetric assay. Calorimetric assay is the combination of the power in watts measured in a calorimeter with the effective specific power (P{sub eff}) in watts/g Pu, determined either by nondestructive gamma-ray assay or by destructive mass spectrometry, to yield the total elemental plutonium mass in the sample. To use a PuO{sub 2} sample as a heat standard for calorimetry, one must determine both the plutonium mass and P{sub eff} with very small uncertainties and then calculate the sample watts from the known plutonium mass, specific powers, and isotopic composition. Well-characterized PuO{sub 2} standards have plutonium mass values determined by analytical chemistry with a precision and accuracy on the order of 0.1%-0.2% relative to the total mass of the sample. Mass spectrometry, typically used to determine the isotopic fractions of plutonium standards, is very accurate and precise for the major isotopes but is somewhat less precise for low-abundance isotopes. The characterization of the {sup 241}Am/Pu ratio in the standard is also of great importance because {sup 241}Am can contribute significantly to P{sub eff} and to the heat output of the standard. The determination of the {sup 241}Am/Pu ratio in a plutonium-bearing sample is a process that is less standardized than mass spectrometry. There are no certified reference materials (CRMs) traceable to the national measurement system for {sup 241}Am in plutonium, and routine analytical {sup 241}Am/Pu ratio measurements often exhibit uncertainties of several percent relative to the total plutonium or greater.

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.

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

Characterizing fallout material using Cs and Pu atom ratios in environmental samples from the FDNPP fallout zone

Science.gov (United States)

Richards, David; Dunne, James; Martin, Peter; Scott, Tom; Yamashiki, Yosuke; Coath, Chris; Chen, Hart

2017-04-01

Here we report the use of combined of Cs and Pu isotope measurements to investigate the extensive plumes of radioactive fallout from the disaster at Fukishima Daiichi nuclear power plant (FNDPP) in March 2011. Among the aims of our study are improved assessment of the physico-chemical nature and changing distribution of land-based fallout. 135Cs/137Cs and 134Cs/137Cs atom ratios are indicative of conditions that relate to the nuclear fission reactions responsible for producing the respective radiocaesium isotopes, and offer much more in terms of forensic and chronological analysis than monitoring 137Cs alone. We briefly present methods to quantify the atom ratios of Cs and Pu isotopes in soil, lichen and moss samples from FDNPP catchment using mass spectrometry (ThermoTRITON for Cs and ThermoNEPTUNE for Pu). High precision data from Fukushima are presented (e.g decay corrected 135Cs/137Cs atom ratio = 0.384 ± 0.001 (n = 5) for roadside dust from Iitate region), and these are in agreement with prelimary estimates by others. We also confirm results for IAEA-330, a spinach sample collected from Polesskoe, Ukraine and subject to contamination from the Chernobyl accident. In addition to Cs isotopes, we adopt Pu isotopes to add a further dimension to the forensic analysis. We discuss the corrections required for background levels prior to the disaster, possibility for multiple components of fallout and complicating factors associated with remobilisation during the clean-up operation. In parallel with this work on digests and leaches from bulk environmental samples, we are refining methods for particle identification, isolation and characterisation using a complementary sequence of cutting-edge materials and manipulation techniques, including combined electron microscopy, focused ion beam techniques (Dualbeam), nano/micro manipulators and nano-scale imaging x-ray photoelectron spectroscopy (NanoESCA) and microCT.

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.

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)

The role of certified reference materials in material control and accounting

International Nuclear Information System (INIS)

Turel, S.P.

1979-01-01

One way of providing an adequate material control and accounting system for the nuclear fuel cycle is to calculate material unaccounted for (MUF) after a physical inventory and to compare the limit of error of the MUF value (LEMUF) against prescribed criteria. To achieve a meaningful LEMUF, a programme for the continuing determination of systematic and random errors is necessary. Within this programme it is necessary to achieve traceability of all Special Nuclear Material (SNM) control and accounting measurements to an International/National Measurement System by means of Certified Reference Materials. SNM measurements for control and accounting are made internationally on a great variety of materials using many diverse measurement procedures by a large number of facilities. To achieve valid overall accountability over this great variety of measurements there must be some means of relating all these measurements and their uncertainties to each other. This is best achieved by an International/National Measurement System (IMS/NMS). To this end, all individual measurement systems must be compatible to the IMS/NMS and all measurement results must be traceable to appropriate international/national Primary Certified Reference Materials. To obtain this necessary compatibility for any given SNM measurement system, secondary certified reference materials or working reference materials are needed for every class of SNM and each type of measurement system. Ways to achieve ''traceability'' and the various types of certified reference material are defined and discussed in this paper. (author)

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

LASL analytical chemistry program for fissionable materials safeguards

International Nuclear Information System (INIS)

Jackson, D.D.; Marsh, S.F.

1979-01-01

Gas-solid reactions at elevated temperature, used previously to convert uranium in refractory forms to species readily soluble in acid, are being applied to thorium materials. A microgram-sensitive spectrophotometric method was developed for determining uranium and the LASL Automated Spectrophotometer has been modified to use it. The instrument now is functional for determining milligram amounts of plutonium, and milligram and microgram amounts of uranium. Construction of an automated controlled-potential-coulometric analyzer has been completed. It is giving design performance of 0.1% relative standard deviation for the determination of plutonium using a method developed especially for the instrument. A method has been developed for the microcomplexometric titration of uranium in its stable (VI) oxidation state. A color probe analyzer assembled for this titration also has been used for microcomplexometric titration of thorium. The present status of reference materials prepared for NBS and for the SALE program, as well as examples of working reference materials prepared for use with nondestructive analyzers, is given. The interlaboratory measured value of the 239 Pu half-life is 24,119 y. Just completed measurement of the half life of 241 Pu is 14.38 y. Measurement of the 240 Pu half life is in progress

USTUR Whole Body Case 0262: 33-y Follow-up of PuO2 In A Skin Wound and Associated Axillary Node

Energy Technology Data Exchange (ETDEWEB)

James, Anthony C.; Sasser, Lyle B.; Stuit, Dorothy B.; Wood, T. G.; Glover, Samuel E.; Lynch, Timothy P.; Dagle, Gerald E.

2008-01-28

This whole body donation case (USTUR Registrant) involved two suspected plutonium oxide (Pu) inhalation intakes, each indicated by a measurable Pu alpha activity in a single urine sample, followed about 1.5 y later by a puncture wound to the thumb while working in a Pu glovebox. The study is concerned with modeling simultaneously the biokinetics of deposition and retention in the respiratory tract and at the wound site; and the biokinetics of Pu subsequently transferred to other body organs, until the donor's death. Urine samples taken after the wound incident had readily measurable Pu alpha activity over the next 14 y, before dropping below the minimum detectable excretion rate (<0.4 mBq per day). The Registrant died about 33 y after the wound intake, at the age of 71, from hepatocellular carcinoma with extensive metastases. At autopsy, all major soft tissue organs were harvested for analysis of their Pu-238, Pu-239+240 and Am-241 content. The amount of Pu-239+240 retained at the wound site was 68 ± 7 Bq (1 SD), measured by low-energy planar Ge spectrometry. A further 56.0 ± 1.2 Bq was retained in an associated axillary lymph node, measured by radiochemistry. Simultaneous mathematical analysis (modelling) of all in vivo urinary excretion data, together with the measured lung, thoracic lymph node, wound, axillary lymph node and systemic tissue contents at death, yielded estimated intake amounts of 757 and 1504 Bq, respectively, for the first and second inhalation incidents, and 204 Bq for the total wound intake. The inhaled Pu material was highly insoluble, with an estimated long-term absorption rate from the lungs of 2 E-5 per day. The Pu material deposited at the wound site was mixed: 14% was rapidly absorbed, 49% was absorbed at the rate of about 6E-5 per day, and the remainder ( 37%) was absorbed extremely slowly (at the rate of about 5E-6 per day). Thus, it was estimated that only 40% of the Pu initially deposited in the wound had been absorbed

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)

Methodology and levels of {sup 137} Cs, {sup 90} Sr and {sup 239} {sup +} {sup 240} Pu in marine sediments from the Brazilian Southern Coast

Energy Technology Data Exchange (ETDEWEB)

Figueira, R.C.L. [Universidade Cruzeiro do Sul - CETEC/UNICSUL - Sao Paulo/SP (Brazil); Tessler, M.G.; Mahiques, M.M. de [Instituto Oceanografico da Univesidade de Sao Paulo - IOUSP - Sao Paulo/SP (Brazil); Cunha, I.I.L. [Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP -Sao Paulo/SP (Brazil)]. e-mail: figueira@curiango.ipen.br

2004-07-01

Methodologies for analysis of {sup 137} Cs, {sup 90} Sr and {sup 239} {sup +} {sup 240} Pu were developed and applied to sediment samples collected along the Brazilian coast. This paper presents the instrumental steps for {sup 137} Cs analysis and the radiochemical steps necessary to analyse {sup 90} Sr and {sup 239} {sup +} {sup 240} Pu. The analytical quality control for radionuclide analysis was verified by participation in international intercomparison exercise running by IAEA as well as in reference material analysis. Further, methodologies were applied in sediments collected from 1976 to 1986 at the Brazilian southern coastal region. {sup 137}Cs levels ranged from 0.37 to 2.03 Bq kg{sup -1}, for {sup 90} Sr from MDC to 8.2 Bq kg{sup -1} and for {sup 239} {sup +} {sup 240} Pu from MDC to 227 m Bq kg{sup -1}. The minimum detectable concentration values (MDC) for {sup 90} Sr and {sup 239} {sup +} {sup 240} Pu were of 0.3 Bq kg{sup -1} and 4.2 mBq kg{sup -1}, respectively. The artificial radioactivity levels in Brazilian sediments are typical values due to fallout deposition and represent reference values for our country. (Author)

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

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

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

AQCS 1989 - Intercomparison runs reference materials

International Nuclear Information System (INIS)

1989-01-01

The purpose of the Analytical Quality Control Services (AQCS) programme provided by the International Atomic Energy Agency (Agency) is to assist laboratories engaged in the analysis of nuclear, environmental, biological, and materials of marine origin for radionuclide, major, minor and trace elements, as well as stable isotopes using atomic and nuclear analytical techniques, to check the quality of their work. Reference Materials available are listed by origin and by analyte giving referenced values and confidence intervals. Only materials, which have one or more properties sufficiently well established from statistical evaluation of previous interlaboratory comparison studies are included. Existing Reference Materials may be updated for previously referenced constituents or properties according to the results of the Agency's Co-ordinated Research Programmes (CRPs) in these fields or according to recently published literature values. They are supplied with a reference sheet stating relevant parameters and properties of the material and can be used as secondary standards for quality control assurance within a laboratory, for checking analytical methods and/or instrumentation or for training purposes. 4 tabs

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

235Uranium isotope abundance certified reference material for gamma spectrometry EC nuclear reference material 171 certification report

International Nuclear Information System (INIS)

De Bievre, P.; Eschbach, H.L.; Lesser, R.; Meyer, H.; Audenhove, Van J.

1986-01-01

This certification report contains the information necessary for the final certification of EC nuclear reference material 171. It is also intended to inform the user of the reference material concerned on technical/scientific details which are not given in the certificate. The report describes the reference material which consists of sets of U 3 O 8 samples with five different 235 U/U abundances, filled in cylindrical aluminium cans. The can bottom serves as window for emitted gamma radiation. The report describes how the 235 U/U abundances were characterized, how the other properties relevant for gamma measurements were determined and gives all connected results as well as those from the verification measurements. Appendix A represents the draft certificate. 32 refs

Reference materials for microanalytical nuclear techniques

Energy Technology Data Exchange (ETDEWEB)

Injuk, Jasna; Grieken, Rene van [Department of Chemistry, Micro and Trace Analysis Centre, University of Antwerp, Wilrijk-Antwerp (Belgium)

1994-07-01

This paper discusses some issues concerning reference materials required for microanalysis including physical and chemical properties of the sample matrix and homogeneity of the chemical composition. It gives some examples of the mst common standards used. Further the paper gives background information about the Micro- and Trace Analysis Center of the University of Antwerp, Belgium and discusses recent results of the Center in microanalysis of reference materials.

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.

239, 240, 241Pu fingerprinting of plutonium in western US soils using ICPMS: solution and laser ablation measurements

International Nuclear Information System (INIS)

Cizdziel, James V.; Ketterer, Michael E.; Farmer, Dennis; Faller, Scott H.; Hodge, Vernon F.

2008-01-01

-members. A rapid total dissolution procedure, followed by extraction chromatography and SF-ICPMS solution Pu analysis, generates excellent agreement with certified 239+240 Pu activities for standard reference materials NIST 4350b, NIST 4353, NIST 4357, and IAEA 385. 239+240 Pu activities and atom ratios determined by total dissolution reveal isotopic information in agreement with the LA-ICPMS dataset regarding the ubiquitous mixing of NTS and stratospheric fallout Pu sources in the regional environment. For several specific samples, the total dissolution method reveals that Pu is incompletely recovered by simpler HNO 3 -HCl leaching procedures, since some of the Pu originating from the NTS is contained in refractory siliceous particles. (orig.)

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

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

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).

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

The importance of reference materials in doping-control analysis.

Science.gov (United States)

Mackay, Lindsey G; Kazlauskas, Rymantas

2011-08-01

Currently a large range of pure substance reference materials are available for calibration of doping-control methods. These materials enable traceability to the International System of Units (SI) for the results generated by World Anti-Doping Agency (WADA)-accredited laboratories. Only a small number of prohibited substances have threshold limits for which quantification is highly important. For these analytes only the highest quality reference materials that are available should be used. Many prohibited substances have no threshold limits and reference materials provide essential identity confirmation. For these reference materials the correct identity is critical and the methods used to assess identity in these cases should be critically evaluated. There is still a lack of certified matrix reference materials to support many aspects of doping analysis. However, in key areas a range of urine matrix materials have been produced for substances with threshold limits, for example 19-norandrosterone and testosterone/epitestosterone (T/E) ratio. These matrix-certified reference materials (CRMs) are an excellent independent means of checking method recovery and bias and will typically be used in method validation and then regularly as quality-control checks. They can be particularly important in the analysis of samples close to threshold limits, in which measurement accuracy becomes critical. Some reference materials for isotope ratio mass spectrometry (IRMS) analysis are available and a matrix material certified for steroid delta values is currently under production. In other new areas, for example the Athlete Biological Passport, peptide hormone testing, designer steroids, and gene doping, reference material needs still need to be thoroughly assessed and prioritised.

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

Radioactive certified reference materials

International Nuclear Information System (INIS)

Watanabe, Kazuo

2010-01-01

Outline of radioactive certified reference materials (CRM) for the analysis of nuclear materials and radioactive nuclides were described. The nuclear fuel CRMs are supplied by the three institutes: NBL in the US, CETAMA in France and IRMM in Belgium. For the RI CRMs, the Japan Radioisotope Association is engaged in activities concerning supply. The natural-matrix CRMs for the analysis of trace levels of radio-nuclides are prepared and supplied by NIST in the US and the IAEA. (author)

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)

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

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)

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

Total cross section of 242Pu between 0.7 and 170 MeV

International Nuclear Information System (INIS)

Moore, M.S.; Lisowski, P.W.; Morgan, G.L.; Auchampaugh, G.F.

1979-01-01

Various evaluations of the neutron cross sections of 242 Pu lead to widely different predictions of bulk neutronics properties such as critical mass. These evaluations also show rather different behavior of the energy dependence of the total cross section. The total cross section of 242 Pu from 0.7 to 170 MeV was measured to a statistical accuracy of = 0.5% below 6 MeV, using 8 g of high purity material and the WNR pulsed neutron facility. Recent evaluations by Madland and Young and by Lagrange and Jary are found to be reasonably consistent with the data obtained. Best agreement, however, is found by using a relationship between the total cross sections for 238 U, 239 Pu, and 235 U. The remarkable accuracy of this description for 242 Pu suggests that it could be extended to other deformed actinides for which inadequate amounts of material exist for direct measurements of sigma/sub T/ in the MeV region, as an evaluation constraint

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

Effect of Fast Neutron to MA/PU Burning/Transmutation Characteristic Using a Fast Reactor

International Nuclear Information System (INIS)

Marsodi; Lasman, As Natio; Kimamoto, A.; Marsongkohadi; Zaki, S.

2003-01-01

MA/Pu burning/transmutation has been studied and evaluated using fast neutrons. Generally, neutron density at this fast burner reactor and transmutation has spectrum energy level around 0.2 MeV with wide enough variation, i.e. from low neutron spectrum to its peak is 0.2 MeV. This neutron spectrum energy level depends on the kind of cooler material or fuel used. Neutron spectrum higher than fast power reactor neutron spectrum is found by means of changing oxide fuel by metallic fuel and changing natrium cooler material by metallic or gas cooler material. This evaluation is conducted by various variations in accordance with the kind of fuel or cooler, MA/Pu fractions and fuel comparison fraction with respect to its cooler in order to get better neutron usage and MA/Pu burning speed. Reactor calculation evaluation in this paper was conducted with 26-group nuclear data cross section energy spectrum. The main purpose of the discussion is to know the effect of fast neutrons to burning/transmutation MA/Pu using fast neutrons

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

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.

How well can we measure U and Pu on an interlaboratory basis?

International Nuclear Information System (INIS)

De Bievre, P.; Mayer, K.

1991-01-01

In measurements in general, and nuclear measurements in particular, it is no more a secret that the real state-of-the-practice (SOP) is frequently different from what is said at Conferences, written in books or claimed in meetings. Frequently the latter refer to the state-of-the-art (SOA) in research laboratories or to the ultimate possible only achievable in a few highly specialized institutes. Since it is important to have an objective basis to determine where the authors stand in SOP, CBNM is running a program to regularly determine the SOP on an interlaboratory basis for U and Pu element and isotope assay: REIMEP (Regular European Interlaboratory Measurement Evaluation Program). Participation is open to non-European countries. Well characterized samples are distributed to participants with characteristics undisclosed until participants' measurements have been received. Subsequently pictures are provided displaying (a) the interlaboratory spread, (b) the deviation of each participant to the carefully characterized reference value, (c) the participant's own estimate of his uncertainty allowing comparison with other participant's uncertainties and the uncertainty of the reference value. Thus the pictures act as instant photographs (snapshots) of the real SOP. The choice of the analytical method is up to the participant (titrimetry, coulometry, α-spectrometry, gas mass spectrometry, γ-spectrometry, thermionic mass spectrometry,...). The quoted uncertainty is also the participant's choice, but should be an accuracy defined as an uncertainty range claiming, for all practical purposes, to contain the true value. Up to now a number of rounds have been performed on various U and/or Pu containing materials such as pellets, powders, solutions, UF 6 . A number of graphs displaying the SOP will be shown

AQCS 1990. Intercomparison runs, reference materials

International Nuclear Information System (INIS)

1990-01-01

The purpose of the Analytical Quality Control Services (AQCS) programme provided by the International Atomic Energy Agency (Agency) is to assist laboratories engaged in the analysis of nuclear, environmental, biological, and materials of marine origin for radionuclide, major, minor and trace elements, as well as stable isotopes using atomic and nuclear analytical techniques, to check the quality of their work. Such a control is necessary since results of analytical activities may be the basis upon which economic, administrative, medical or legal decisions are taken; they must, therefore, be documented to be sufficiently reliable. The Agency has instituted the AQCS-programme which for 1990 will involve distributing samples for Intercomparison Runs and Reference Materials in a way similar to that of previous years. The Agency's Analytical Quality Control Services (AQCS) programme provides mainly three types of materials: materials which can be used in analytical laboratories working in the fields of nuclear technology and isotope hydrology. These include uranium ore Reference Materials and other substances of interest for nuclear fuel technology as well as stable isotope Reference Materials for mass spectrometric determination of isotope ratios in natural waters; materials with known content of uranium, thorium and/or transuranium elements or fission products for the determination of environmental radioactivity or control of nuclear safety; materials for use in the determination of stable trace elements in environmental, biomedical and marine research. Radiochemical methods such as neutron activation or isotope dilution analysis are often used in the determination of such trace elements and constitute an important contribution of nuclear techniques to applied science. Tabs

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.

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)

Preparation and characterization of the fish reference material

International Nuclear Information System (INIS)

Ulrich, Joao Cristiano

2011-01-01

The certified reference materials (CRMs) play an important role in obtaining measurement results traceable to the International System of Units, through an unbroken chain of comparisons. Thus, the demand for new certified reference materials (CRMs) increases every day in all areas of knowledge. The availability of reference materials, mainly in Brazil is still incipient, given that the demand far exceeds the available variety of these materials. The amount of certified reference materials available in the country is insufficient to meet the need of the scientific community and demands for development of new methodologies. Among the many areas in need of reference materials, we highlight the importance for the food trade balance for these products within the country. The certification of food products, intended both for export and for domestic consumption, requires analysis methods that provide precise and accurate results to ensure product quality. This paper describes the preparation and certification of a reference material in the fish matrix in mercury and methylmercury. The study brings together since the stage of material selection, preparation, development of homogeneity and stability studies and characterization. The certification was performed by means of measurements using two analytical techniques, flow injection analysis - cold vapor atomic absorption spectrometry (FIA-CV-AAS) and isotope dilution applied to mass spectrometry (IDMS), which is a primary method. In this work the standards of the ISO 30 (ABNT 30-34) and ISO Guide 35 was used as the basis for the preparation and characterization of the material. For the calculation of uncertainties was used the GUM and Eurachem guide. As a result, was produced and certified a lot of material in relation to the concentration of mercury (Hg = 0.271 ± 0.057 mg g -1 ) and methylmercury (MeHg = 0.245 ± 0.038 mg g -1 ), and informational values of lead and arsenic. (author)

Biological reference materials and analysis of toxic elements

Energy Technology Data Exchange (ETDEWEB)

Subramanian, R; Sukumar, A

1988-12-01

Biological monitoring of toxic metal pollution in the environment requires quality control analysis with use of standard reference materials. A variety of biological tissues are increasingly used for analysis of element bioaccumulation, but the available Certified Reference Materials (CRMs) are insufficient. An attempt is made to review the studies made using biological reference materials for animal and human tissues. The need to have inter-laboratory studies and CRM in the field of biological monitoring of toxic metals is also discussed.

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.

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.

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.

Preparation standardisation and use of plutonium nitrate reference solutions

International Nuclear Information System (INIS)

Brown, M.L.; Drummond, J.L.

1981-07-01

A procedure is described for the purification of a plutonium nitrate solution in nitric acid for use as a plutonium master standard. Anion exchange chromatography followed by oxalate precipitation is used to purify the plutonium and the residual cationic impurities are analysed by emission spectroscopy. The plutonium content is accurately and precisely measured by two independent methods, namely by gravimetry as PuO 2 at 1250 0 C and by ceric oxidation, ferrous reduction and dichromate titration. Full details of the purification procedure are given, with recommended methods for storing and using the standard solution. It is concluded that such a solution is the most satisfactory reference material, available for plutonium analysis for reprocessing plants, and is adequately related to other, internationally accepted, standard reference materials. (author)

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...

USTUR whole body case 0262: 33-y follow-up of PuO{sub 2} in a skin wound and associated axillary node

Energy Technology Data Exchange (ETDEWEB)

James, A.C.; Sasser, L.B.; Stuit, D.B.; Wood, T.G. [U.S. Transuranium and Uranium Registries, College of Pharmacy, Washington State University, 1845 Terminal Drive, Suite 201, Richland, WA 99354 (United States); Glover, S.E. [Department of Mechanical, Industrial and Nuclear Engineering, University of Cincinnati, 598 Rhodes Hall, Cincinnati, OH 45221 (United States); Lynch, T.P. [Pacific Northwest National Laboratory, PO Box 999, Richland, WA 99354 (United States); Dagle, G.E. [2543 Harris Avenue, Richland, WA 99354 (United States)

2007-07-01

This whole body donation case (USTUR Registrant) involved two suspected PuO{sub 2} inhalation intakes, each indicated by a measurable Pu alpha activity in a single urine sample, followed about 1 1/2 y later by a puncture wound to the thumb while working in a Pu glovebox. The study is concerned with modelling simultaneously the biokinetics of deposition and retention in the respiratory tract and at the wound site; and the biokinetics of Pu subsequently transferred to other body organs, until the donor's death. Urine samples taken after the wound incident had readily measurable Pu alpha activity over the next 14 y, before dropping below the minimum detectable excretion rate (<0.4 mBq d{sup -1}). The Registrant died about 33 y after the wound intake, at the age of 71, from hepatocellular carcinoma with extensive metastases. At autopsy, all major soft tissue organs were harvested for analysis of their {sup 238}Pu, {sup 239+240}Pu and {sup 241}Am content. The amount of {sup 239+240}Pu retained at the wound site was 68{+-}7 Bq (1 SD), measured by low-energy planar Ge spectrometry. A further 56.0{+-}1.2 Bq was retained in an associated axillary lymph node, measured by radiochemistry. Simultaneous mathematical analysis (modelling) of all in vivo urinary excretion data, together with the measured lung, thoracic lymph node, wound, axillary lymph node and systemic tissue contents at death, yielded estimated intake amounts of 757 and 1504 Bq, respectively, for the first and second inhalation incidents, and 204 Bq for the total wound intake. The inhaled Pu material was highly insoluble, with an estimated long-term absorption rate from the lungs of 2 x 10{sup -5} d{sup -1}. The Pu material deposited at the wound site was mixed: {approx}14% was rapidly absorbed, {approx}49% was absorbed at the rate of about 6 x 10{sup -5} d{sup -1}, and the remainder ({approx}37%) was absorbed extremely slowly (at the rate of about 5 x 10{sup -6} d{sup -1}). Thus, it was estimated that only

Development of solid water-equivalent radioactive certified reference materials

International Nuclear Information System (INIS)

Finke, E.; Greupner, H.; Groche, K.; Rittwag, R.; Geske, G.

1991-01-01

This paper presents a brief description of the development of solid water-equivalent beta volume radioactive certified reference materials. These certified reference materials were prepared for the beta fission nuclides 90 Sr/ 90 Y, 137 Cs, 147 Pm and 204 Tl. Comparative measurements of liquid and solid water-equivalent beta volume radioactive certified reference materials are discussed. (author)

Criticality Data for Spherical 235U, 239Pu, and 237Np Systems Reflector-Moderated by Low Capturing-Moderator Materials

International Nuclear Information System (INIS)

Loaiza, David J.; Stratton, William

2004-01-01

The critical dimensions of spherical systems moderated and reflected by low-capturing materials such as D 2 O, BeO, Be, and C were investigated. A parametric study of the critical mass of enriched uranium, plutonium, and neptunium is examined and tabulated. The results obtained expand on the understanding of reflector-moderated critical systems, and they show regions of unstable criticality for 235 U and 239 Pu reflected cores at intermediate densities. This instability is illustrated by calculations of the positive reactivity coefficient of volume expansion. The coefficient is positive, not negative, in the intermediate density region for 235 U and 239 Pu systems. For 237 Np cores reflected by the same moderator, the effect is negligible. The critical dimensions were calculated with the DANTSYS codes using the Hansen-Roach cross-section libraries. This study is both a summary of mostly unpublished calculations and new calculations. Experimental data for these configurations are extremely limited. These are examined in the text when applicable

Measurement of the fission cross-section of {sup 235}U and {sup 239}Pu for thermal neutrons; Mesures des sections de fission de {sup 235}U et de {sup 239}Pu en neutrons thermiques

Energy Technology Data Exchange (ETDEWEB)

Fraysse, G; Prosdocimi, A; Netter, F; Samour, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1965-07-01

Improved techniques of fast detection have been applied for determining the fission cross-sections of {sup 235}U and {sup 239}Pu with reference to the absorption cross-section of Boron. Monochromatic neutron beams of 0.0322 eV, 0.0626 eV and 0.275 eV have been employed. Use has been made of a Xe-filled gaseous scintillator and of a low-geometry solid state ion chamber. Both measured alpha and fission rates. The results at the reference energy of 0.0253 eV are: ({sigma}{sub F}){sub 0} {sup 235}U = 588 {+-} 10 barns ({sigma}{sub F}){sub 0} {sup 239}Pu = 738 {+-} 7 barns. (authors) [French] Des techniques avancees de comptage rapide ont ete mise en oeuvre pour determiner la section efficace de fission de {sup 235}U et de {sup 239}Pu par rapport a celle d'absorption du bore. Des faisceaux de neutrons monochromatiques de 0,0322 eV, 0,0626 eV et 0,275 eV ont ete employes. Les detecteurs utilises sont un scintillateur gazeux rempli de xenon et une chambre d'ionisation a etat solide a basse geometrie. Les deux ont mesure les taux des desintegrations alpha et des fissions. Les resultats a l'energie de reference de 0,0253 eV sont: ({sigma}{sub F}){sub 0} {sup 235}U = 588 {+-} 10 barns ({sigma}{sub F}){sub 0} {sup 239}Pu = 738 {+-} 7 barns. (auteurs)

New reference materials improvement of methods of measurements

International Nuclear Information System (INIS)

Marchandise, H.

1985-01-01

The report summarizes the development of about 120 reference materials in a variety of fields (non ferrous metals, trace element analysis, food products, biomedical analysis, physical and technical properties of solid materials). The document also provides practical advice for trace element analyses, describes the principles followed for certifying reference materials and provides recommendations for their use

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.

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}.

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)

Development of solid water-equivalent radioactive certified reference materials

Energy Technology Data Exchange (ETDEWEB)

Finke, E.; Greupner, H.; Groche, K.; Rittwag, R. (Office for Standardization, Metrology and Quality Control (ASMW), Berlin (Germany, F.R.)); Geske, G. (Jena Univ. (Germany, F.R.))

1991-01-01

This paper presents a brief description of the development of solid water-equivalent beta volume radioactive certified reference materials. These certified reference materials were prepared for the beta fission nuclides {sup 90}Sr/{sup 90}Y, {sup 137}Cs, {sup 147}Pm and {sup 204}Tl. Comparative measurements of liquid and solid water-equivalent beta volume radioactive certified reference materials are discussed. (author).

Study of public understanding and evaluation of messages concerning the policy of 'Pu thermal utilization' based on results of interview survey

International Nuclear Information System (INIS)

Tsuchiya, Tomoko; Kosugi, Motoko; Senda, Yasuko; Takada, Kaori; Iwatsuki, Akihito; Tamagawa, Hiromi

2008-01-01

In this paper, we focus on the kind of information the nuclear industry should provide for the general public to understand and trust in the plan of plutonium utilization for mixed-oxide fuel in light water reactors, i.e., Pu thermal utilization. We conducted an interview survey for 30 people who live in the Tokyo metropolitan area to analyze what they know and how they feel about Pu thermal utilization, and to compare three information materials based on their subjective evaluation of the degree of understanding, trust and so on. The content analysis of interviewees' comments regarding Pu thermal utilization shows that they have vague but correct knowledge, that is, 'Pu thermal utilization is to recycle nuclear fuel or nuclear waste.' However, people do not have background information concerning the necessity of Pu utilization, such as the resource limitation of uranium. According to the comparative analysis of the three materials, a material that presents the necessity and usefulness of Pu thermal utilization using figures and graphs was evaluated most understandable, informative, trustful, and persuasive. The material including information of risk was evaluated more informative, but the evaluation of trust indicated a divided opinion. People who feel anxiety about nuclear power generation evaluated the material including risk messages more trustful than other materials. Others evaluated it less trustful because the risk management of Pu thermal utilization and the process to solve remaining problems, such as HLW disposal, are uncertain. (author)

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

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)

Preparation and certification of Sargasso seaweed reference material

Energy Technology Data Exchange (ETDEWEB)

Okamoto, Kensaku

1988-01-01

Sargasso seaweed reference material was prepared from Sargassum felvellum obtained from an unpolluted area in Japan. The sargasso samples were washed, freeze-dried, pulverized, sieved to pass a 80-mesh screen and finally homogenized. Collaborative studies on the elemental analysis of the sargasso reference material were performed using various analytical techniques. Certified values are provided for Ag, As, Ca, Cd, Co, Cu, Fe, K, Mg, Mn, Na, Pb, Rb, Sr, V and Zn, based on results of determinations by at least three independent analytical techniques. Reference values are reported for Al, Br, Cl, Cr, Cs, Hg, I, P, S, Sb, Sc, Se, Ti and U. The sargasso certified reference material contains high levels of alkali metals, alkaline earth metals, I, Br, As and U, while the concentration of trace elements may be considered to be at the lower end of the range of reported values for marine brown algae. The sargasso sample will be of practical use in marine and environmental sciences as a certified reference material having an elemental composition close to background levels.

The European experience in safeguarding nuclear fuel recycle processes and Pu stores

International Nuclear Information System (INIS)

Synetos, Sotiris

2013-01-01

Civil nuclear programs in the European Union member states have from their onset included fuel recycling as an option. The EURATOM Treaty gives to the European Commission the obligation to apply safeguards controls to all civil Nuclear Material in the European Union, and to facilitate the implementation of IAEA safeguards. The European Commission (EURATOM) has thus gained years of experience in safeguarding reprocessing plants, Pu storages, and MOX fuel fabrication plants and is currently participating in the development of approaches and measures for safeguarding long term repositories. The aim of this paper is to present the regulator's views and experience on safeguarding nuclear fuel recycle processes and Pu stores, which is based on the following principles: -) Early involvement of the control organizations in the design of the safeguards measures to be developed for a plant (currently referred to as Safeguards by Design); -) Early definition of a safeguards strategy including key measurement points; -) The design and development of plant specific Safeguards equipment, including an on site laboratory for sample analysis; -) The development by the operator of an appropriate Nuclear Material accountancy system to facilitate their declaration obligations; -) The introduction of an inspection regime allowing comprehensive controls under the restrictions imposed by financial and Human Resources limitations; -) Optimization of the inspection effort by using unattended measuring stations, containment and surveillance systems and secure remote transmission of data to the regulator's headquarters. The paper is followed by the slides of the presentation. (authors)

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

IAEA AQCS catalogue for reference materials and intercomparison exercises 1998/1999

International Nuclear Information System (INIS)

1999-01-01

Fore more than thirty years the International Atomic Energy Agency (IAEA), through its Analytical Quality Control Services (AQCS) programme, has been assisting Member States' laboratories to maintain and improve the reliability of their analyses by organizing intercomparison exercises and by preparing and distributing biological, environmental and marine reference materials. The catalogue consists principally of two parts: The list of all available IAEA reference materials grouped into five categories: reference materials for radionuclides; reference materials for trace, minor and major elements, including oxides; reference materials for stable isotopes; reference materials for organic contaminants and methyl mercury containing materials. Lists of all available IAEA reference materials sorted by analytes. In addition information on recommended half-life data and suppliers of radioactive sources is provided. Planned intercomparisons are advertised and request forms for participation in intercomparisons are included. Forms for ordering reference materials, quality control spectra for gamma-spectrometry on diskettes and AQCS related publications are also provided

Analytical quality control service programme, intercomparison runs, certified reference materials, reference materials 1987-88

International Nuclear Information System (INIS)

1986-12-01

The purpose of the Analytical Quality Control Services (AQCS) programme provided by the IAEA, is to assist laboratories engaged in the analysis of nuclear, environmental, biological, and materials of marine origin for radionuclide, major, minor and trace elements, as well as stable isotopes using atomic and nuclear analytical techniques, to check the quality of their work. The tables give details of the intercomparison samples and reference materials distributed by the IAEA in the period 1987 to 1988. 2 tabs

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.

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.)

Static electric dipole polarizabilities of tri- and tetravalent U, Np, and Pu ions.

Science.gov (United States)

Parmar, Payal; Peterson, Kirk A; Clark, Aurora E

2013-11-21

High-quality static electric dipole polarizabilities have been determined for the ground states of the hard-sphere cations of U, Np, and Pu in the III and IV oxidation states. The polarizabilities have been calculated using the numerical finite field technique in a four-component relativistic framework. Methods including Fock-space coupled cluster (FSCC) and Kramers-restricted configuration interaction (KRCI) have been performed in order to account for electron correlation effects. Comparisons between polarizabilities calculated using Dirac-Hartree-Fock (DHF), FSCC, and KRCI methods have been made using both triple- and quadruple-ζ basis sets for U(4+). In addition to the ground state, this study also reports the polarizability data for the first two excited states of U(3+/4+), Np(3+/4+), and Pu(3+/4+) ions at different levels of theory. The values reported in this work are the most accurate to date calculations for the dipole polarizabilities of the hard-sphere tri- and tetravalent actinide ions and may serve as reference values, aiding in the calculation of various electronic and response properties (for example, intermolecular forces, optical properties, etc.) relevant to the nuclear fuel cycle and material science applications.

Mechanical and dielectric characterization of lead zirconate titanate(PZT)/polyurethane(PU) thin film composite for energy harvesting

Science.gov (United States)

Aboubakr, S.; Rguiti, M.; Hajjaji, A.; Eddiai, A.; Courtois, C.; d'Astorg, S.

2014-04-01

The Lead Zirconate titanate (PZT) ceramic is known by its piezoelectric feature, but also by its stiffness, the use of a composite based on a polyurethane (PU) matrix charged by a piezoelectric material, enable to generate a large deformation of the material, therefore harvesting more energy. This new material will provide a competitive alternative and low cost manufacturing technology of autonomous systems (smart clothes, car seat, boat sail, flag ...). A thin film of the PZT/PU composite was prepared using up to 80 vol. % of ceramic. Due to the dielectric nature of the PZT, inclusions of this one in a PU matrix raises the permittivity of the composite, on other hand this latter seems to decline at high frequencies.

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.

Minimization of the volume and Pu content of the waste generated at a plutonium fuel fabrication plant

International Nuclear Information System (INIS)

Pauwels, H.

1992-01-01

The amounts of waste generated during 1987, 1989 and a past reference period have been reported in great detail. The main conclusions which can be drawn from these figures are: (i) for all kinds of waste, the waste-to-product ratio has decreased very substantially during the past few years. This reduction results partly from a scale effect, i.e. the better load factor of the plant, and partly from Belgonucleare's continuous effort to minimize the radioactive waste arisings; (ii) the ratio of the Pu content of the waste to the total Pu throughput of the plant has also decreased substantially; (iii) the mean Pu content of the solid Pu contaminated waste equals 1.39 g Pu per unit volume of 25 l. Only for a small fraction of this waste (<5% by volume) does the Pu content exceed 5 g per unit volume of 25 l; (iv) even after the implementation of waste reducing measures, some 45% of the solid Pu contaminated waste is generated by operations which involve the handling and transfer of powders. Finally, some 63% of the total amount of Pu in the waste can be imputed to these operations

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.)

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.)

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

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)

Translocation dynamics of Pu(NO3)4 and PuO2 from puncture wounds to lymph nodes and major organs of beagles

International Nuclear Information System (INIS)

Bistline, R.W.; Lebel, J.L.; Dagle, G.E.

1976-01-01

The translocation dynamics of plutonium and americium from simulated puncture wounds in the paws of beagle dogs following contamination with Pu(NO 3 ) 4 and high-fired PuO 2 was studied. Fractions of initial implant transported to the first major lymph node and to major body organs were measured with in vivo counting equipment and by radiochemical analysis of tissue material collected at necropsy. Samples were obtained from serial necropsies ranging from 2 weeks to 1 year after implant. The difference in lymph node and organ-accumulation dynamics between the two chemical forms and the effects of diethylenetriaminepentaacetate (DTPA) chelation treatment are presented. Active mechanisms to transport plutonium to and from the lymph system appear to exist. Equations for buildup in the lymph nodes and organs are included. The data suggest a buildup in the lymph node to a maximum, followed by a long negative slope, and a possible dose-rate effect from Pu(NO 3 ) 4 in lymph nodes

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).

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

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.

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)

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.

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.

Co-electrospun blends of PU and PEG as potential biocompatible scaffolds for small-diameter vascular tissue engineering

International Nuclear Information System (INIS)

Wang, Heyun; Feng, Yakai; Fang, Zichen; Yuan, Wenjie; Khan, Musammir

2012-01-01

A small-diameter vascular graft (inner diameter 4 mm) was fabricated from polyurethane (PU) and poly(ethylene glycol) (PEG) solutions by blend electrospinning technology. The fiber diameter decreased from 1023 ± 185 nm to 394 ± 106 nm with the increasing content of PEG in electrospinning solutions. The hybrid PU/PEG scaffolds showed randomly nanofibrous morphology, high porosity and well-interconnected porous structure. The hydrophilicity of these scaffolds had been improved significantly with the increasing contents of PEG. The mechanical properties of electrospun hybrid PU/PEG scaffolds were obviously different from that of PU scaffold, which was caused by plasticizing or hardening effect imparted by PEG composition. Under hydrated state, the hybrid PU/PEG scaffolds demonstrated low mechanical performance due to the hydrophilic property of materials. Compared with dry PU/PEG scaffolds with the same content of PEG, the tensile strength and elastic modulus of hydrated PU/PEG scaffolds decreased significantly, while the elongation at break increased. The hybrid PU/PEG scaffolds demonstrated a lower possibility of thrombi formation than blank PU scaffold in platelet adhesion test. The hemolysis assay illustrated that all scaffolds could act as blood contacting materials. To investigate further in vitro cytocompatibility, HUVECs were seeded on the scaffolds and cultured over 14 days. The cells could attach and proliferate well on the hybrid scaffolds than blank PU scaffold, and form a cell monolayer fully covering on the PU/PEG (80/20) hybrid scaffold surface. The results demonstrated that the electrospun hybrid PU/PEG tubular scaffolds possessed the special capacity with excellent hemocompatibility while simultaneously supporting extensive endothelialization with the 20 and 30% content of PEG in hybrid scaffolds. - Highlights: ► We develop small-diameter vascular grafts made of PU and PEG by electrospinning. ► The hybrid scaffolds could suppress the platelet

²³⁸PuO₂ Fuel and Dosimetry

Energy Technology Data Exchange (ETDEWEB)

Mayo, Douglas R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rawool-Sullivan, Mohini [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Garner, Scott Edward [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wenz, Tracy R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-06-01

²³⁸Pu is an ideal material for use as a heat source with its half-life of 87.7 years and copious particle emissions. ²³⁸Pu radioisotope thermoelectric generators (RTGs) have found use for pacemakers, Apollo Space missions, Mars rovers, and Voyager spacecraft. In evaluating the dose to personnel and components near a ²³⁸Pu-based RTG, a number of additional nuclides and their daughter products must be considered to get an accurate estimate for γ-dose, and the amount of ¹⁷O and ¹⁸O for the neutron-dose must be considered. This paper looks at the contributing nuclides and their daughter products that add the most to the dose rates.

Determination of carbon-14 in environmental level, solid reference materials

Energy Technology Data Exchange (ETDEWEB)

Blowers, Paul, E-mail: paul.blowers@cefas.co.uk [Cefas Lowestoft Laboratory, Pakefield Road, Lowestoft, Suffolk, NR33 0HT (United Kingdom); Caborn, Jane, E-mail: jane.a.caborn@nnl.co.uk [NNL, Springfields, Salwick, Preston, Lancashire, PR4 0XJ (United Kingdom); Dell, Tony [Veterinary Laboratories Agency, New Haw, Addlestone, Surrey, KT15 3NB (United Kingdom); Gingell, Terry [DSTL, Radiation Protection Services, Crescent Road, Alverstoke, Gosport, Hants, PO12 2DL (United Kingdom); Harms, Arvic [National Physical Laboratory, Hampton Road, Teddington, Middlesex, TW11 0LW (United Kingdom); Long, Stephanie [Radiological Protection Institute of Ireland, 3 Clonskeagh Square, Clonskeagh Road, Dublin 14, Ireland (United Kingdom); Sleep, Darren [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster, LA1 4AP (United Kingdom); Stewart, Charlie [UKAEA (Waste Management Group), Chemical Support Services, D1310/14, Dounreay, Thurso, Caithness, KW14 7TZ (United Kingdom); Walker, Jill [Radiocarbon Dating, The Old Stables, East Lockinge, Wantage, Oxon OX12 8QY (United Kingdom); Warwick, Phil E. [GAU-Radioanalytical, National Oceanography Centre Southampton, European Way, Southampton, SO14 3ZH (United Kingdom)

2011-10-15

An intercomparison exercise to determine the {sup 14}C activity concentrations in a range of solid, environmental level materials was conducted between laboratories in the UK. IAEA reference materials, C2, C6 and C7, and an in-house laboratory QA material were dispatched in 2006 to ten laboratories comprising of members of the Analyst Informal Working Group (AIWG) and one other invited party. The laboratories performed the determinations using a number of techniques, and using the results each one was evaluated in terms of levels of precision, sensitivity and limits of detection. The results of the study show that all techniques are capable of successfully analysing {sup 14}C in environmental level materials, however, a shortage of certified environmental reference materials exists. The suitability of the IAEA reference materials and other material for use as reference materials was also assessed.

Determination of carbon-14 in environmental level, solid reference materials

International Nuclear Information System (INIS)

Blowers, Paul; Caborn, Jane; Dell, Tony; Gingell, Terry; Harms, Arvic; Long, Stephanie; Sleep, Darren; Stewart, Charlie; Walker, Jill; Warwick, Phil E.

2011-01-01

An intercomparison exercise to determine the 14 C activity concentrations in a range of solid, environmental level materials was conducted between laboratories in the UK. IAEA reference materials, C2, C6 and C7, and an in-house laboratory QA material were dispatched in 2006 to ten laboratories comprising of members of the Analyst Informal Working Group (AIWG) and one other invited party. The laboratories performed the determinations using a number of techniques, and using the results each one was evaluated in terms of levels of precision, sensitivity and limits of detection. The results of the study show that all techniques are capable of successfully analysing 14 C in environmental level materials, however, a shortage of certified environmental reference materials exists. The suitability of the IAEA reference materials and other material for use as reference materials was also assessed.

Use of gamma spectrometry for analysis of three reference materials

International Nuclear Information System (INIS)

Kinova, L.

2004-01-01

All reference materials (Reference material A: weight = 49.23 g; Reference material B: weight = 36.08 g; Reference material C: weight = 26.18 g) were packed in 50 cm 3 polypropylene vials, sealed and measured consecutively three times at intervals of the average of 25 days. Low background gamma spectrometry system: HPGe detector with high energy resolution (FWHM for 1332 KeV of Co-60 is 1.9 KeV, Relative counting efficiency for the same energy is 21 %) was used. Results: All materials are of low activity and must be measured for a long time.The highest specific activity of a man-made radionuclides Cs-137 and Am-241 is in the material A. An instrumentally measurable activity of Pb-210 also can be observed in this material. Medium values are in the material B. The reference material C according to the specific activity seems to be a low natural radioactivity material with highest activity of natural nuclides Th-232 and Pa-234 (progeny of U-238). Conclusions: Gamma spectrometry is an useful tool for initial measurement of materials with low radioactivity. Such measurements give an orientation for the nuclides content and approximate activity in the material for the following radiochemical determinations

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

Drop Calculations of HLW Canister and Pu Can-in-Canister

International Nuclear Information System (INIS)

Sreten Mastilovic

2001-01-01

The objective of this calculation is to determine the structural response of the standard high-level waste (HLW) canister and the canister containing the cans of immobilized plutonium (Pu) (''can-in-canister'' [CIC] throughout this document) subjected to drop DBEs (design basis events) during the handling operation. The evaluated DBE in the former case is 7-m (23-ft) vertical (flat-bottom) drop. In the latter case, two 2-ft (0.61-m) corner (oblique) drops are evaluated in addition to the 7-m vertical drop. These Pu CIC calculations are performed at three different temperatures: room temperature (RT) (20 C), T = 200 F = 93.3 C , and T = 400 F = 204 C ; in addition to these the calculation characterized by the highest maximum stress intensity is performed at T = 750 F = 399 C as well. The scope of the HLW canister calculation is limited to reporting the calculation results in terms of: stress intensity and effective plastic strain in the canister, directional residual strains at the canister outer surface, and change of canister dimensions. The scope of Pu CIC calculation is limited to reporting the calculation results in terms of stress intensity, and effective plastic strain in the canister. The information provided by the sketches from Reference 26 (Attachments 5.3,5.5,5.8, and 5.9) is that of the potential CIC design considered in this calculation, and all obtained results are valid for this design only. This calculation is associated with the Plutonium Immobilization Project and is performed by the Waste Package Design Section in accordance with Reference 24. It should be noted that the 9-m vertical drop DBE, included in Reference 24, is not included in the objective of this calculation since it did not become a waste acceptance requirement. AP-3.124, ''Calculations'', is used to perform the calculation and develop the document

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

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.

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.

An outline of reference materials for analysis techniques in China

International Nuclear Information System (INIS)

Zhang Yuanxun; Qian Yine; Zhang Yongping; Tong Yongpeng

1994-01-01

This paper provides background information on the development in the field of reference materials in China. The major considerations in development of reference materials include homogeneity, stability, handling procedures and certification. Further it discusses the plans for development in the near future specific natural-matrix reference materials containing low levels of trace elements and having high degree of homogeneity

An outline of reference materials for analysis techniques in China

Energy Technology Data Exchange (ETDEWEB)

Yuanxun, Zhang; Yine, Qian; Yongping, Zhang; Yongpeng, Tong [Shanghai Institute of Nuclear Research, Academia Sinica (China)

1994-07-01

This paper provides background information on the development in the field of reference materials in China. The major considerations in development of reference materials include homogeneity, stability, handling procedures and certification. Further it discusses the plans for development in the near future specific natural-matrix reference materials containing low levels of trace elements and having high degree of homogeneity.

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

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....

{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.

Development and use of reference materials and quality control materials

International Nuclear Information System (INIS)

2003-04-01

Current knowledge is summarized on correct use of commercially available certified reference materials (CRMs) and reference materials (RMs). Acknowledged are also the limitations and restrictions analysts have to face if they want to apply quality control. The concept of in-house RMs or quality control materials (QCMs) is advocated to supplement the use of CRMs for quality control purposes. On hand advice on how to select, prepare, characterize and use these QCMs is given from the experts' perspective. Several scenarios are described to make this concept widely applicable to: advanced laboratories with CRMs with validated analytical techniques available, laboratories with less experience and facilities, as well as cases were labile compounds and unstable matrices are involved. Each scenario considers different approaches to overcome the lack of appropriate CRMs and advise on the preparation of QCMs, which might fit the particular purpose

Development and use of reference materials and quality control materials

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-04-01

Current knowledge is summarized on correct use of commercially available certified reference materials (CRMs) and reference materials (RMs). Acknowledged are also the limitations and restrictions analysts have to face if they want to apply quality control. The concept of in-house RMs or quality control materials (QCMs) is advocated to supplement the use of CRMs for quality control purposes. On hand advice on how to select, prepare, characterize and use these QCMs is given from the experts' perspective. Several scenarios are described to make this concept widely applicable to: advanced laboratories with CRMs with validated analytical techniques available, laboratories with less experience and facilities, as well as cases were labile compounds and unstable matrices are involved. Each scenario considers different approaches to overcome the lack of appropriate CRMs and advise on the preparation of QCMs, which might fit the particular purpose.

Rate of Pu(IV) polymer formation in nitric acid solutions. A parametric study

Energy Technology Data Exchange (ETDEWEB)

Toth, L.M.; Osborne, M.M.

1984-07-01

The kinetics of Pu(IV) polymer formation has been examined with the intent of developing a simple mathematical equation that would predict the appearance of polymer. The fundamental polymerization rate has been found to be dependent on [Pu(IV)]{sup 1} {sup 2} and [HNO{sub 3}]{sup -6}. The activation energy for polymer formation is real temperature dependent, varying from 66.9 kJ/mol (16 kcal/mol) at 25{sup 0}C to 150.5 kJ/mol (36 kcal/mol) at 105{sup 0}C. These relationships have guided the developement of an empirical model that gives time to form 2% polymer in hours, t = [Pu/sub T/]/sup a/[HNO{sub 3}]/sup b/ Ae/sup c/T/, where a = -1.6, b = 4.6, c = 12.300 K, and A = 7.66 x 10{sup -16} h M{sup -3}; [Pu/sub T/] is the total plutonium concentration, mol/L; and [HNO{sub 3}] is the makeup nitric acid concentration, mol/L. 11 references, 26 figures, 1 table.

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

A new certified reference material for size analysis of nanoparticles

International Nuclear Information System (INIS)

Braun, Adelina; Kestens, Vikram; Franks, Katrin; Roebben, Gert; Lamberty, Andrée; Linsinger, Thomas P. J.

2012-01-01

A certified reference material, ERM-FD100, for quality assurance and validation of various nanoparticle sizing methods, was developed by the Institute for Reference Materials and Measurements. The material was prepared from an industrially sourced colloidal silica containing nanoparticles with a nominal equivalent spherical diameter of 20 nm. The homogeneity and stability of the candidate reference material was assessed by means of dynamic light scattering and centrifugal liquid sedimentation. Certification of the candidate reference material was based on a global interlaboratory comparison in which 34 laboratories participated with various analytical methods (DLS, CLS, EM, SAXS, ELS). After scrutinising the interlaboratory comparison data, 4 different certified particle size values, specific for the corresponding analytical method, could be assigned. The good comparability of results allowed the certification of the colloidal silica material for nanoparticle size analysis.

Reference materials for micro-analytical nuclear techniques

International Nuclear Information System (INIS)

Valkovic, V.; Zeisler, R.; Bernasconi, G.; Danesi, P.R.

1994-01-01

Direct application of many existing reference materials in micro-analytical procedures such as energy dispersive x-ray fluorescence (EDXRF), particle induced x-ray emission spectroscopy (PIXE) and ion probe techniques for the determination of trace elements is often impossible or difficult because: 1) other constituents present in large amounts interfere with the determination; 2) trace components are not sufficiently homogeneously distributed in the sample. Therefore specific natural-matrix reference materials containing very low levels of trace elements and having high degree of homogeneity are required for many micro-analytical procedures. In this report, selection of the types of environmental and biological materials which are suitable for micro-analytical techniques will be discussed. (author)

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

Biological and environmental reference materials in CENAM.

Science.gov (United States)

Arvizu-Torres, R; Perez-Castorena, A; Salas-Tellez, J A; Mitani-Nakanishi, Y

2001-06-01

Since 1994, when the NIST/NOAA Quality Assurance Program in Chemical Measurements was discussed in Queretaro, CENAM, the National Measurement Institute (NMI) of Mexico, has become involved in the development of reference materials. In the field of biological and environmental reference materials, in particular, the NORAMET collaboration program with NIST and NRC, and the North-American Environmental Cooperation signed among three free-trade treaty organizations, have greatly helped the development of the materials metrology program in the newly established CENAM. This paper describes some particularly significant efforts of CENAM in the development of biological and environmental reference materials, on the basis of inter-comparison studies organized with local and governmental environmental agencies of Mexico. In the field of water pollution CENAM has developed a practical proficiency testing (PT) scheme for field laboratories, as a part of registration by local government in the metropolitan area, according to the Mexican Ecological Regulation. The results from these eight PTs in the last 5 years have demonstrated that this scheme has helped ensure the reliability of analytical capability of more than 50 field laboratories in three states, Mexico, D.F., and the States of Mexico and Queretaro. Similar experience has been obtained for more than 70 service units of stack emission measurements in the three states in 1998 and 1999, as a result of the design of a PT scheme for reference gas mixtures. This PT scheme has been accomplished successfully by 30 analytical laboratories who provide monitoring services and perform research on toxic substances (Hg, methylmercury, PCB, etc.) in Mexico. To support these activities, reference samples have been produced through the NIST SRMs, and efforts have been made to increase CENAM's capability in the preparation of primary reference materials in spectrometric solutions and gas mixtures. Collaboration among NMIs has also

REFERENCE MATERIALS IN THE SPHERE OF USE OF ATOMIC ENERGY

Directory of Open Access Journals (Sweden)

V. A. Borisov

2015-01-01

Full Text Available The article describes the chronology of development of the system of reference materials in the nuclear industry of the Russian Federation. The basic documents used in the sphere of nuclear energy are described. The nomenclature of reference materials and feature of their application in the "Rosatom" is given. The prospects of development activities in the field of reference materials are formulated.

Development of natural matrix reference materials for monitoring environmental radioactivity

International Nuclear Information System (INIS)

Holmes, A.S.; Houlgate, P.R.; Pang, S.; Brookman, B.

1992-01-01

The Department of the Environment commissioned the Laboratory of the Government Chemist to carry out a contract on natural matrix reference materials. A survey of current availability of such materials in the western world, along with the UK's need, was conducted. Four suitable matrices were identified for production and validation. Due to a number of unforeseen problems with the collection, processing and validation of the materials, the production of the four identified reference materials was not completed in the allocated period of time. In the future production of natural matrix reference materials the time required, the cost and the problems encountered should not be underestimated. Certified natural matrix reference materials are a vital part of traceability in analytical science and without them there is no absolute method of checking the validity of measurement in the field of radiochemical analysis. (author)

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)

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)

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.

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

Preparation and analysis of a marble reference material

International Nuclear Information System (INIS)

Carmo Freitas, M.; Moens, L.; Seabra e Barros, J.

1988-01-01

A 7 kg stone of a Carrara marble was reduced to grains smaller than 100 μm, mixed and homogenized in order to prepare a marble reference material. The homogeneity was tested for 16 elements by instrumental neutron activation analysis (INAA). Through a one-way analysis of variance based on several analyses of each of 15 bottles and within the same bottle, it was concluded that the inter-bottle heterogeneity is not greater than the intra-bottle heterogeneity. Results on the concentration of major and trace elements in the marble reference material, obtained by different laboratories and different techniques, are given. The limestone certified reference material KALKSTEIN KH was used to evaluate measurement accuracy, to intercalibrate laboratories, and to provide compatibility of measurement data. (author) 10 refs.; 12 tabs

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

Preparation of in-house graphite reference material for boron

International Nuclear Information System (INIS)

Kumar, Sanjukta A.; Venkatesh, K.; Swain, Kallola K.; Manisha, V.; Kamble, Granthali S.; Pandey, Shailaja P.; Remya Devi, P.S.; Ghosh, M.; Verma, R.

2016-05-01

Graphite is extensively used in nuclear technology. Boron concentration in graphite is one of the important parameters that decide its acceptability for nuclear applications. Reliable analytical methods are essential for the determination of boron in graphite at concentration about 5 mg kg -1 . Reference materials are used for validation of existing analytical methods and developing new methodologies. In view of the importance of determination of boron in graphite and unavailability of graphite reference material, an In-house graphite reference material was prepared in Analytical Chemistry Division. Graphite source material was procured, processed to obtain powder of ≤ 75 μm (200 mesh) and bottled. Procedures were developed for the determination of boron in graphite using inductively coupled plasma optical emission spectrometry (ICPOES) and inductively coupled plasma mass spectrometry (ICPMS) techniques. Homogeneity testing was carried out on the bottled units and boron content along with the combined and expanded uncertainties were established. The assigned boron concentration in the In-house graphite reference material is (7.3±0.46) mg kg -1 . (author)

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.

Certification of a niobium metal reference material for neutron dosimetry (EC nuclear reference material 526)

International Nuclear Information System (INIS)

Ingelbrecht, C.; Pauwels, J.

1990-01-01

Niobium metal, of 99.999% nominal purity, in the form of 0.02 and 0.1 mm thick foil and of 0.5 mm diameter wire, has been certified for its tantalum mass fraction. The certified value of the tantalum mass fraction is 0.3 ± 0.09 mg. Kg -1 , and is based on 70 results obtained by six independent laboratories by neutron activation analysis or inductively coupled plasma mass spectrometry. The material is intended to be used as a reference material in neutron metrology

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)

Reference material IAEA 413: Major, minor and trace elements in algae

International Nuclear Information System (INIS)

2010-01-01

Reference materials are a basic requirement for any sort of quantitative chemical and radiochemical analysis. Laboratories need them for calibration and quality control throughout their analytical work. The IAEA started to produce reference materials in the early 1960s to meet the needs of the analytical laboratories in its Member States that required reference materials for quality control of their measurements. The initial efforts were focused on the preparation of environmental reference materials containing anthropogenic radionuclides for use by those laboratories employing nuclear analytical techniques. These reference materials were characterized for their radionuclide content through interlaboratory comparison involving a core group of some 10 to 20 specialist laboratories. The success of these early exercises led the IAEA to extend its activities to encompass both terrestrial and marine reference materials containing primordial radionuclides and trace elements. Today, the IAEA has more than 90 reference materials and maintains a customer base of about 5000 members from more than 85 Member States. Within the frame of IAEA activities in production and certification of RM, this report describes the certification of the IAEA 413: Major, minor and trace elements in algae. Details are given on methodologies and data evaluation

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

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

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)

Graphene-based filament material for thermal ionization

Energy Technology Data Exchange (ETDEWEB)

Hewitt, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Shick, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Siegfried, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-09-19

The use of graphene oxide materials for thermal ionization mass spectrometry analysis of plutonium and uranium has been investigated. Filament made from graphene oxide slurries have been 3-D printed. A method for attaching these filaments to commercial thermal ionization post assemblies has been devised. Resistive heating of the graphene based filaments under high vacuum showed stable operation in excess of 4 hours. Plutonium ion production has been observed in an initial set of filaments spiked with the Pu 128 Certified Reference Material.

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)

Instrumental neutron activation analysis of marine sediment in-house reference material

International Nuclear Information System (INIS)

Nazaratul Ashifa Abdullah Salim; Mohd Suhaimi Hamzah; Mohd Suhaimi Elias; Siong, W.B.; Shamsiah Abdul Rahman; Azian Hashim; Shakirah Abdul Shukor

2013-01-01

Reference materials play an important role in demonstrating the quality and reliability of analytical data. The advantage of using in-house reference materials is that they provide a relatively cheap option as compared to using commercially available certified reference material (CRM) and can closely resemble the laboratory routine test sample. A marine sediment sample was designed as an in-house reference material, in the framework of quality assurance and control (QA/QC) program of the Neutron Activation Analysis (NAA) Laboratory at Nuclear Malaysia. The NAA technique was solely used for the homogeneity test of the marine sediment sample. The CRM of IAEA- Soil 7 and IAEA- SL1 (Lake Sediment) were applied in the analysis as compatible matrix based reference materials for QA purposes. (Author)

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)

Certification of a nickel metal reference material for neutron dosimetry (EC Nuclear Reference Material 521)

International Nuclear Information System (INIS)

Pauwels, J.

1988-01-01

Nickel metal, of 99.99 % nominal purity and natural isotopic composition, in the form of 0.1 mm thick foil and 0.5 mm diameter wire has been certified for its cobalt mass fraction. The certified value of cobalt (<0.1μg.g-1) is based on 38 results obtained by neutron activation analysis, emission spectrometry with inductively coupled plasma excitation and atomic absorption spectrometry, whereas the isotopic composition of the nickel was verified by thermal ionization mass spectrometry. The material is intended to be used as a reference material in neutron metrology

Certification of an aluminium metal reference material for neutron dosimetry (EC nuclear reference material 523)

International Nuclear Information System (INIS)

Pauwels, J.; Ingelbrecht, C.

1990-01-01

Aluminium metal of > 99.999% nominal purity in the form of 0.1 mm and 1 mm thick foil and of 1 mm diameter wire has been certified for its sodium mass fraction. The certified value of the sodium mass fraction ( -1 ) is based on 21 results from three laboratories using two different methods, which are neutron activation analysis and atomic absorption spectrometry. The overall purity was estimated using spark source mass spectrometry and neutron activation analysis. The material is intended to be used as a reference material in neutron metrology

A comparative study of nitride purity and Am fabrication losses in PuN materials by the powder and internal gelation production routes

Energy Technology Data Exchange (ETDEWEB)

Hedberg, Marcus, E-mail: marhed@chalmers.se; Ekberg, Christian

2016-12-15

Fabrication of plutonium containing fuels through the internal gelation method has mostly been studied in mixed metal systems such as U, Pu or Zr,Pu. In this work production of undiluted PuN has been performed by carbothermal reduction on both oxide powder and Pu microspheres produced by the internal gelation method. Nitride purities reached using the different methods have been studied together with final densities achieved during pellet fabrication as well as losses of ingrown Am during the different production steps. Formation of Pu microspheres was successfully performed using the internal gelation method, although extensive microsphere fracturing occurred during thermal treatment. Final densities of PuN pellets produced by cold pressing and sintering reached 70–80% of theoretical density. Am losses during the carbothermal reduction step was on average about 3.7%. After sintering about 11% of Am was lost in total through the entire production process if sintering in N{sub 2} + 5% H{sub 2} atmosphere while about 50% of the Am in total was lost when using Ar as sintering atmosphere. - Highlights: • Internal gelation Pu based sols was performed. • Nitride formation by carbothermal reduction on Pu microspheres and powders was performed. • Pelletization and sintering of pellets was performed. • Am losses were measured throughout the production steps.

Production of candidate natural matrix reference materials for micro-analytical techniques

International Nuclear Information System (INIS)

Zeisler, R.; Fajgelj, A.; Zeiller, E.

2002-01-01

Homogeneity is considered to be the most vital prerequisite for a certified reference material (CRM); more stringent requirements exist for the analysis of small subsamples. Many of the natural matrix CRMs are prepared from bulk samples by grinding and milling them to a certain particle size, which is expected to provide a more homogenous material; however recommended sample sizes for biological and environmental reference materials are found to be more than 100 mg. Since the milling of materials is costly and has some drawbacks, natural materials that already occur as small particles such as air particulate matter, certain sediments, and cellular biological materials may form the basis of the required reference materials. The nature of these materials, i.e. naturally occurring particles, may provide ideal model reference material. We describe here the production of the materials and preliminary tests, the evaluation for the micro-analytical techniques

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)

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.

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.

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).

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.

Analysis of {sup 236}U and plutonium isotopes, {sup 239,240}Pu, on the 1 MV AMS system at the Centro Nacional de Aceleradores, as a potential tool in oceanography

Energy Technology Data Exchange (ETDEWEB)

Chamizo, Elena; López-Lora, Mercedes [Centro Nacional de Aceleradores (Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Junta de Andalucía), Thomas Alva Edison 7, 41092 Seville (Spain); Villa, María [Departamento de Física Aplicada II, Universidad de Sevilla, Av. Reina Mercedes 4A, 41012 Seville (Spain); Servicio de Radioisótopos, Centro de Investigación, Tecnología e Innovación, Universidad de Sevilla, Av. Reina Mercedes 4B, 41012 Seville (Spain); Casacuberta, Núria [Laboratory of Ion Beam Physics, ETH Zürich, Otto-Stern-Weg 5, CH-8093 Zürich (Switzerland); López-Gutiérrez, José María [Centro Nacional de Aceleradores (Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Junta de Andalucía), Thomas Alva Edison 7, 41092 Seville (Spain); Departamento de Física Aplicada I, Escuela Universitaria Politécnica, Universidad de Sevilla, Virgen de África 7, 41011 Seville (Spain); Pham, Mai Khanh [IAEA-Environment Laboratories, Monte Carlo 98000 (Monaco)

2015-10-15

The performance of the 1 MV AMS system at the CNA (Centro Nacional de Aceleradores, Seville, Spain) for {sup 236}U and {sup 239,240}Pu measurements has been extensively investigated. A very promising {sup 236}U/{sup 238}U abundance sensitivity of about 3 × 10{sup −11} has been recently achieved, and background figures for {sup 239}Pu of about 10{sup 6} atoms were reported in the past. These promising results lead to the use of conventional low energy AMS systems for the analysis of {sup 236}U and {sup 239}Pu and its further application in environmental studies. First {sup 236}U results obtained on our AMS system for marine samples (sediments and water) are presented here. Results of two new IAEA reference materials (IAEA-410 and IAEA-412, marine sediments from Pacific Ocean) are reported. The obtained {sup 236}U/{sup 239}Pu atom ratios, of 0.12 and 0.022, respectively, show a dependency with the contamination source (i.e. local fallout from the US tests performed at the Bikini Atoll and general fallout). The results obtained for a third IAEA reference material (IAEA-381, seawater from the Irish Sea), are also presented. In the following, the uranium and plutonium isotopic compositions obtained on a set of 5 intercomparison seawater samples from the Arctic Ocean provided by the ETH Zürich are discussed. By comparing them with the obtained results on the 600 kV AMS facility Tandy at the ETH Zürich, we demonstrate the solidity of the CNA technique for {sup 236}U/{sup 238}U determinations at, at least, 7 × 10{sup −10} level. Finally, these results are discussed in their environmental context.

Development of сertified reference materials set for opened porosity of solid substances and materials (imitators

Directory of Open Access Journals (Sweden)

E. P. Sobina

2016-01-01

Full Text Available The article deals with data of research for development of certified reference materials set for opened porosity of solid substances and materials (imitators (OPTB SO UNIIM Set Certified Reference Materials GSO 10583-2015. The certified values of opened porosity of metal cylinders were established by the method of hydrostatic weighing before and after boring of holes in. The certified reference materials are intended for calibration and verification of measuring instruments of opened porosity, based on the Boyle - Mariotte's law.

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

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)

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)

Eksperymentalny korpus litewskiej gwary puńskiej w Polsce (narzędzie do badań nad gwarami polskimi i litewskimi na Suwalszczyźnie

Directory of Open Access Journals (Sweden)

Danuta Roszko

2015-06-01

Full Text Available Experimental corpus of the Lithuanian local dialect of Puńsk in Poland (a tool for the study on the Polish and Lithuanian local dialects in the Suwałki Region The linguistic resources included in EkorpGP present a great cognitive value for Polish and Lithuanian dialectologists. Particularly valuable for researchers of the Lithuanian local dialects, including the local dialect of Puńsk, is subcorpus A. The material included in EKorpGP confirms that the local dialect is incessantly evolving. The typical dialectal features vanish for the sake of the standardized Lithuanian language. Whereas, subcorpora B and C are a good base for studies on the processes of the language interference in the speech of the bilingual Lithuanians of Puńsk. Amongst the potential recipients of these subcorpora it is possible also to find dialectologists dealing with the local dialects of the Suwałki Region, as well as researchers of the Polish language spoken to the east of the Polish border. The polonization suggested in EKorpGP (with reference to subcorpus A along with subcorpora B and C will ensure a credible source of information for a wide circle of researchers of the phenomena of sociological, ethnological, cultural and historical nature. It should also be taken into account that the issues raised in the utterances given by the Lithuanians of Puńsk will capture the interest of politicians dealing with the national minorities in Poland. The extraordinary value of the materials collected in EKorpGP results from the fact that they reflect the economic, political and civilization transformations of the turbulent period of 1986–2012 in Poland, Lithuania and Europe.

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.)

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)

Reference materials and their role in quality assurance in environmental monitoring

International Nuclear Information System (INIS)

Cortes, Eduardo

2002-01-01

The importance of a good and routine quality control procedure for the analyses of environmental samples is presented. The use of Reference Materials as one simple procedure for validating analytical methodologies and determining the accuracy of analytical data is emphasized. The quality of the reference materials is also discussed as well as their selection and correct use. The convenience of preparing 'in-house' reference materials is discussed and attention is called to relevant aspects to be considered. An example of the preparation of a reference material is presented and some aspects of the procedure are discussed. (author)

137Cs and 239+240Pu levels in the Asia-Pacific regional seas

International Nuclear Information System (INIS)

Duran, E.B.; Povinec, P.P.; Fowler, S.W.; Airey, P.L.; Hong, G.H.

2004-01-01

137 Cs and 239+240 Pu data in seawater, sediment and biota from the regional seas of Asia-Pacific extending from 50 deg. N to 60 deg. S latitude and 60 deg. E to 180 deg. E longitude based on the Asia-Pacific Marine Radioactivity Database (ASPAMARD) are presented and discussed. 137 Cs levels in surface seawater have been declining to its present median value of about 3 Bq/m 3 due mainly to radioactive decay, transport processes, and the absence of new significant inputs. 239+240 Pu levels in surface seawater are much lower, with a median of about 6 mBq/m 3 . 239+240 Pu appears to be partly scavenged by particles and is therefore more readily transported down the water column. As with seawater, 239+240 Pu concentrations are lower than 137 Cs in surface sediment. The median 137 Cs concentration in surface sediment is 1.4 Bq/kg dry, while that of 239+240 Pu is only 0.2 Bq/kg dry. The vertical profiles of both 137 Cs and 239+240 Pu in the sediment column of coastal areas are different from deep seas which can be attributed to the higher sedimentation rates and additional contribution of run-offs from terrestrial catchment areas in the coastal zone. Comparable data for biota are far less extensive than those for seawater and sediment. The median 137 Cs concentration in fish (0.2 Bq/kg wet) is higher than in crustaceans (0.1 Bq/kg wet) or mollusks (0.1 Bq/kg wet). Benchmark values (as of 2001) for 137 Cs and 239+240 Pu concentrations in seawater, sediment and biota are established to serve as reference values against which the impact of future anthropogenic inputs can be assessed. ASPAMARD represents one of the most comprehensive compilations of available data on 137 Cs and 239+240 Pu in particular, and other anthropogenic as well as natural radionuclides in seawater, sediment and biota from the Asia-Pacific regional seas

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 ...

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

Rede de apoio social de puérperas na prática da amamentação

Directory of Open Access Journals (Sweden)

Lisie Alende Prates

2015-06-01

Full Text Available Objetivo: Conhecer a rede de apoio social das puérperas na prática da amamentação. Métodos: Trata-se de uma pesquisa qualitativa do tipo descritiva, utilizando pressupostos da pesquisa participante, realizada por meio de entrevista com 21 puérperas. Resultados: O meio familiar ocupou o primeiro lugar na referência das entrevistadas, representado, principalmente, pelas mães das puérperas e outras mulheres da família. A amamentação aparece como um ato permeado por mitos, crenças e valores repassados de geração em geração, sendo fortemente influenciada pela rede de apoio social da puérpera. Conclusão: Enfatiza-se a importância de se conhecer, incentivar e valorizar a presença da rede de apoio social da puérpera, durante a amamentação, de forma a permitir sua participação e colaboração na adesão e manutenção dessa prática.

Recent developments in the field of environmental reference materials at the JRC Ispra.

Science.gov (United States)

Muntau, H

2001-06-01

The production of reference materials for environmental analysis started in the Joint Research Centre at Ispra/Italy in 1972 with the objective of later certification by the BCR, but for obvious budget reasons only a fraction of the total production achieved at Ispra ever reached certification level, although all materials were produced according to the severe quality requirements requested for certified reference materials. Therefore, the materials not destinated to certification are in growing demand as inter-laboratory test materials and as laboratory reference materials, for internal quality control, e.g., by control charts. The history of reference material production within the Joint Research Centre is briefly reviewed and the latest additions described. New developments such as micro-scale reference materials intended for analytical methods requiring sample intakes at milligram or sub-milligram level and therefor not finding supply on the reference material market, and "wet" environmental reference materials, which meet more precisely the "real-world" environmental analysis conditions, are presented and the state-of-the-art discussed.

Chemical speciation of U, Fe, and Pu in melt glass from nuclear weapons testing

Energy Technology Data Exchange (ETDEWEB)

Pacold, J. I.; Lukens, W. W.; Booth, C. H.; Shuh, D. K. [Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Knight, K. B.; Eppich, G. R. [Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Holliday, K. S. [Materials Science Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2016-05-21

Nuclear weapons testing generates large volumes of glassy materials that influence the transport of dispersed actinides in the environment and may carry information on the composition of the detonated device. We determine the oxidation state of U and Fe (which is known to buffer the oxidation state of actinide elements and to affect the redox state of groundwater) in samples of melt glass collected from three U.S. nuclear weapons tests. For selected samples, we also determine the coordination geometry of U and Fe, and we report the oxidation state of Pu from one melt glass sample. We find significant variations among the melt glass samples and, in particular, find a clear deviation in one sample from the expected buffering effect of Fe(II)/Fe(III) on the oxidation state of uranium. In the first direct measurement of Pu oxidation state in a nuclear test melt glass, we obtain a result consistent with existing literature that proposes Pu is primarily present as Pu(IV) in post-detonation material. In addition, our measurements imply that highly mobile U(VI) may be produced in significant quantities when melt glass is quenched rapidly following a nuclear detonation, though these products may remain immobile in the vitrified matrices. The observed differences in chemical state among the three samples show that redox conditions can vary dramatically across different nuclear test conditions. The local soil composition, associated device materials, and the rate of quenching are all likely to affect the final redox state of the glass. The resulting variations in glass chemistry are significant for understanding and interpreting debris chemistry and the later environmental mobility of dispersed material.

Chemical speciation of U, Fe, and Pu in melt glass from nuclear weapons testing

Science.gov (United States)

Pacold, J. I.; Lukens, W. W.; Booth, C. H.; Shuh, D. K.; Knight, K. B.; Eppich, G. R.; Holliday, K. S.

2016-05-01

Nuclear weapons testing generates large volumes of glassy materials that influence the transport of dispersed actinides in the environment and may carry information on the composition of the detonated device. We determine the oxidation state of U and Fe (which is known to buffer the oxidation state of actinide elements and to affect the redox state of groundwater) in samples of melt glass collected from three U.S. nuclear weapons tests. For selected samples, we also determine the coordination geometry of U and Fe, and we report the oxidation state of Pu from one melt glass sample. We find significant variations among the melt glass samples and, in particular, find a clear deviation in one sample from the expected buffering effect of Fe(II)/Fe(III) on the oxidation state of uranium. In the first direct measurement of Pu oxidation state in a nuclear test melt glass, we obtain a result consistent with existing literature that proposes Pu is primarily present as Pu(IV) in post-detonation material. In addition, our measurements imply that highly mobile U(VI) may be produced in significant quantities when melt glass is quenched rapidly following a nuclear detonation, though these products may remain immobile in the vitrified matrices. The observed differences in chemical state among the three samples show that redox conditions can vary dramatically across different nuclear test conditions. The local soil composition, associated device materials, and the rate of quenching are all likely to affect the final redox state of the glass. The resulting variations in glass chemistry are significant for understanding and interpreting debris chemistry and the later environmental mobility of dispersed material.

Determination of ancient ceramics reference material by neutron activation analysis

International Nuclear Information System (INIS)

Li Huhou; Sun Jingxin; Wang Yuqi; Lu Liangcai

1986-01-01

Contents of trace elements in the reference material of ancient ceramics (KPS-1) were determined by means of activation analysis, using thermal neutron irradiation produced in nuclear reactor. KPS-1 favoured the analysis of ancient ceramics because it had not only many kinds of element but also appropriate contents of composition. The values presented here are reliable within the experimental precision, and have shown that the reference material had a good homogeneity. So KPS-1 can be used as a suitable reference material for the ancient ceramics analysis

O papel da enfermeira no ambulatorio de assistência à puérpera

Directory of Open Access Journals (Sweden)

Mª Cristina S. Figueiredo

1993-03-01

Full Text Available A assistência à puérpura no Brasil é analisada no contexto da atenção ao ciclo grávido-puerperal, onde o pré-natal é considerado de baixa eficácia, a atenção ao parto, estanque e o puerperio a etapa esquecida. Nessa perspectiva, é ressaltada a importância da enfermeira na assistência pré, trans e pós-natal, considerando-se a atual sub-utilização dessa profissional nesse processo. Propõe-se a re-orientação da atenção ao puerperio através do retorno à atenção domiciliar, da redução do prazo da primeira consulta à puérpera, da efetiva implantação do sistema de referência e contra-referência, da incorporação de tecnologia adequada e da ampliação da cobertura assistencial.

Low and intermediate level waste in SFR-1. Reference Waste Inventory 2007

International Nuclear Information System (INIS)

Almkvist, Lisa; Gordon, Ann

2007-11-01

The objective with this report is to describe all the waste and the waste package that is expected to be deposited in SFR 1 at the time of closure. The report will form the basis for the release calculation in the safety analysis for SFR 1. Three different scenarios are explored in this report; the waste inventory is based on an estimated operational lifetime of the Swedish nuclear power plants of 50 and 60 years and that closure of the SFR 1 repository will take place in 2040 or 2050 respectively. The third scenario is where the repository is full (one part where the activity adds up to 1016 Bq and one part where the repository is considered full regarding volume). In the report, data about geometries, weights, materials, chemicals and radionuclide are given. No chemotoxic material has been identified in the waste. The inventory is estimated using the Prosit-interface which extracts information from the Triumf database. The inventory is based on so called 'waste types' and the waste types' 'reference waste package'. The reference waste package combined with a prognosis of the number of waste packages to be delivered to SFR 1 gives the final waste inventory for SFR 1. All reference waste packages are thoroughly described in the appendices of this report. The reference waste packages are as far as possible based on actual experiences and measurements. The radionuclide inventory is also based on actual measurements. The inventory is based on measurements of 60 Co and 137 Cs in waste packages and on measurements of 239 Pu and 240 Pu in reactor water. Other nuclides in the inventory are calculated with correlation factors

Reduction of Pu(V) and Np(V) by leonardite humic acids and their quinonoid-enriched derivatives

International Nuclear Information System (INIS)

Shcherbina, N.S.; Kalmykov, St.N.; Perminova, I.V.; Kovalenko, A.N.

2005-01-01

Full text of publication follows: Humic substances (HS) are natural poly-electrolytes ubiquitous in aquatic environment responsible for complexation of metal ions. The presence of phenolic and quinonoid moieties in the structure of HS provide for their ability to take part in redox interactions. Capability of HS to reduce plutonium from higher oxidation states (Pu(V) and Pu(VI)) to tetravalent state was reported in several studies. However, the disparate results were reported for Np(V). The contradicting results on the redox behavior of HS could originate from the structural differences of the humic materials tested, in particular, from varying content of the redox-active quinonoid moieties. To test this hypothesis, the goal of this research was to evaluate reducing performance of leonardite humic acids and of their quinonoid-enriched derivatives with respect to Pu(V) and Np(V). The quinonoid-enriched humic derivatives were obtained using the reaction of formaldehyde co-poly-condensation between parent humic material - leonardite humic acid - and model dihydroxybenzenes - hydroquinone, catechol and 1,4-benzoquinone. The humic material: quinonoid monomer ration of 1 g per 250 mg was used. The reduction of Np(V) was studied at micro- and macro-concentration level: 10 -7 M and 10 -4 M, respectively. In case of Pu(V) the concentration was about 10 -10 M. The HS concentrations varied from 1 to 100 ppm, while ionic strength was zero. All experiments were conducted in anaerobic conditions and in the darkness. The kinetics of Pu(V) reduction was studied using solvent extraction (TTA in toluene); to monitor Np(V) reduction two independent techniques were used: solvent extraction and VIS-NIR spectrophotometry. The latter allows measuring absorbance of NpO 2 + and Np-humate complexes at 981.3 and 987.4 nm, respectively. Fast reduction of Pu(V) by the parent humic material was observed and the reduction rate increased with a decrease in pH. In case of Np(V), there was no

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

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.)

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

Phonon dispersion curves determination in (delta)-phase Pu-Ga alloys

Energy Technology Data Exchange (ETDEWEB)

Wong, J; Clatterbuck, D; Occelli, F; Farber, D; Schwartz, A; Wall, M; Boro, C; Krisch, M; Beraud, A; Chiang, T; Xu, R; Hong, H; Zschack, P; Tamura, N

2006-02-07

We have designed and successfully employed a novel microbeam on large grain sample concept to conduct high resolution inelastic x-ray scattering (HRIXS) experiments to map the full phonon dispersion curves of an fcc {delta}-phase Pu-Ga alloy. This approach obviates experimental difficulties with conventional inelastic neutron scattering due to the high absorption cross section of the common {sup 239}Pu isotope and the non-availability of large (mm size) single crystal materials for Pu and its alloys. A classical Born von-Karman force constant model was used to model the experimental results, and no less than 4th nearest neighbor interactions had to be included to account for the observation. Several unusual features including, a large elastic anisotropy, a small shear elastic modulus, (C{sub 11}-C{sub 12})/2, a Kohn-like anomaly in the T{sub 1}[011] branch, and a pronounced softening of the T[111] branch towards the L point in the Brillouin are found. These features may be related to the phase transitions of plutonium and to strong coupling between the crystal structure and the 5f valence instabilities. Our results represent the first full phonon dispersions ever obtained for any Pu-bearing material, thus ending a 40-year quest for this fundamental data. The phonon data also provide a critical test for theoretical treatments of highly correlated 5f electron systems as exemplified by recent dynamical mean field theory (DMFT) calculations for {delta}-plutonium. We also conducted thermal diffuse scattering experiments to study the T(111) dispersion at low temperatures with an attempt to gain insight into bending of the T(111) branch in relationship to the {delta} {yields} {alpha}{prime} transformation.

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.

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

Hot Experimental Facility reference flowsheet

International Nuclear Information System (INIS)

North, E.D.

1982-01-01

This paper is a useful set of background information of HEF flowsheets, although many changes have been made in the past three years. The HEF reference flowsheet is a modified high-acid PUREX flowsheet capable of operating in the coprocessing mode or with full partitioning of U and Pu. Adequate decontamination factors are provided to purify high-burnup, fast breeder-reactor fuels to levels required for recycle back to a fuel fabrication facility. Product streams are mixed U-Pu oxide and uranium oxide. No contaminated liquid wastes are intentionally discharged to the environment. All wastes are solidified and packaged for appropriate disposal. Acid and water are recovered for internal recycle. Excess water is treated and discharged from the plant stack. Several changes have been made in the reference flowsheet since that time, and these are noted briefly

Phosphated minerals to be used as radioactive reference materials

International Nuclear Information System (INIS)

Braganca, M.J.C.S.; Tauhata, L.; Clain, A.F.; Moreira, I.

2003-01-01

The production and the supplying of certified reference materials, or deliberated contaminated materials containing natural radionuclides for laboratories which analyses environmental samples are fundamentals for the correct measurements of their radioactive levels. This analysis quality represents a important step for the safeguards of the population health, and quality control of the imported and exported products, such as minerals, agricultural and raw materials. The phosphate rocks, containing significant concentrations of thorium, and used as raw material and fertilizers justified a study for better characterization and distinction to be used cas certified reference radioactive materials. Therefore, samples from the two carboanalytical-alkaline chimneys (Araxa and Catalao), and one from metasedimentar origin (Patos de Minas), distant 100 km from each other, were collected and chemical and cholecystographic characterized by optical emission, X-ray diffraction and fluorescence. The element concentrations were determined by neutron activation analysis, ICP-MS and ICP-AES. The results, after multivariate statistical analysis and study of correlations among elements, have shown geochemical similarities of the phosphates from Araxa and Catalao, and differences from Patos de Minas, despite of the geographic proximity. The concentration of thorium between 200 and 500 (mg/g) allows to use such minerals as reference materials

Certification of an iron metal reference material for neutron dosimetry (EC nuclear reference material 524)

International Nuclear Information System (INIS)

Ingelbrecht, C.; Pauwels, J.; Lievens, F.

1993-01-01

Iron metal, of > 99.996% nominal purity, in the form of 0.1 mm thick foil and of 0.5 mm diameter wire has been certified for its manganese and cobalt mass fractions. The certified value of the cobalt mass fraction ( -1 ) is based on 39 accepted results from five laboratories using two different methods. The certified value of the manganese mass fraction ( -1 ) is based on 41 accepted results from five laboratories using three different methods. The overall purity was also verified. The material is intended to be used as a reference material in neutron dosimetry. (authors). 8 refs., 9 tabs., 2 figs

Thermodynamic assessment of the LiF–ThF{sub 4}–PuF{sub 3}–UF{sub 4} system

Energy Technology Data Exchange (ETDEWEB)

Capelli, E. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Department of Radiation Science and Technology, Faculty of Applied Physics, Delft University of Technology, Delft 2629JB (Netherlands); Beneš, O., E-mail: ondrej.benes@ec.europa.eu [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Konings, R.J.M. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Department of Radiation Science and Technology, Faculty of Applied Physics, Delft University of Technology, Delft 2629JB (Netherlands)

2015-07-15

The LiF–ThF{sub 4}–PuF{sub 3}–UF{sub 4} system is the reference salt mixture considered for the Molten Salt Fast Reactor (MSFR) concept started with PuF{sub 3}. In order to obtain the complete thermodynamic description of this quaternary system, two binary systems (ThF{sub 4}–PuF{sub 3} and UF{sub 4}–PuF{sub 3}) and two ternary systems (LiF–ThF{sub 4}–PuF{sub 3} and LiF–UF{sub 4}–PuF{sub 3}) have been assessed for the first time. The similarities between CeF{sub 3}/PuF{sub 3} and ThF{sub 4}/UF{sub 4} compounds have been taken into account for the presented optimization as well as in the experimental measurements performed, which have confirmed the temperatures predicted by the model. Moreover, the experimental results and the thermodynamic database developed have been used to identify potential compositions for the MSFR fuel and to evaluate the influence of partial substitution of ThF{sub 4} by UF{sub 4} in the salt.

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

Low and intermediate level waste in SFR-1. Reference waste inventory

International Nuclear Information System (INIS)

Riggare, P.; Johansson, Claes

2001-06-01

The objective with this report is to describe all the waste and the waste package that is expected to be deposited in SFR-1 at the time of closure. This report is a part of the SAFE project (Safety Assessment of Final Repository for Radioactive Operational Waste), i.e. the renewed safety assessment of SFR-1. The accounted waste inventory has been used as input to the release calculation that has been performed in the SAFE project. The waste inventory is based on an estimated operational lifetime of the Swedish nuclear power plants of 40 years and that closure of the SFR repository will happen in 2030. In the report, data about geometries, weights, materials, chemicals and radionuclide are given. No chemo toxic material has been identified in the waste. The inventory is based on so called waste types and the waste types reference waste package. The reference waste package combined with a prognosis of the number of waste packages to the year 2030 gives the final waste inventory for SFR-1. All reference waste packages are thoroughly described in the appendices of this report. The reference waste packages are as far as possible based on actual experiences and measurements. The radionuclide inventory is also based on actual measurements. The inventory is based on measurements of 60 Co and 137 Cs in waste packages and on measurements 239 Pu and 240 Pu in reactor water. Other nuclides in the inventory are calculated with correlation factors. In the SAFE project's prerequisites it was said that one realistic and one conservative (pessimistic) inventory should be produced. The conservative one should then be used for the release calculations. In this report one realistic and one conservative radionuclide inventory is presented. The conservative one adds up to 10 16 Bq. Regarding materials there is only one inventory given since it is not certain what is a conservative assumption

Fate of 137Cs, 90Sr and 239+240Pu in soil profiles at a water recharge site in Basel, Switzerland.

Science.gov (United States)

Abraham, Johannes; Meusburger, Katrin; Waldis, Judith Kobler; Ketterer, Michael E; Zehringer, Markus

2018-02-01

An important process in the production of drinking water is the recharge of the withdrawn ground water with river water at protected recharge fields. While it is well known that undisturbed soils are efficiently filtering and adsorbing radionuclides, the goal of this study was to investigate their behaviour in an artificial recharge site that may receive rapid and additional input of radionuclides by river water (particularly when draining a catchment including nuclear power plants (NPP)). Soil profiles of recharge sites were drilled and analysed for radionuclides, specifically radiocesium ( 137 Cs), radiostrontium ( 90 Sr) and plutonium ( 239+240 Pu). The distribution of the analysed radionuclides were compared with an uncultivated reference soil outside the recharge site. The main activity of 137 Cs was located in the top soil (4.5-7.5 cm) and reached down to a depth of 84 cm and 48 cm for the recharge and the reference site, respectively. The found activities of 239+240 Pu originate from the global fallout after 1950. 239+240 Pu appeared to be strongly adsorbed onto soil particles. The shape of the depth profile was similar to 137 Cs, but also similar between the recharge and the reference site. In contrast, 90 Sr showed a uniform distribution over the entire depth of the recharge and reference profiles indicating that 90 Sr already entered the gravel zone and the ground water. Elevated inventories of the radionuclides were observed for the recharge site. The soil of the recharge field exhibited a threefold higher activity of 137 Cs compared to the reference soil. Also for 239+240 Pu higher inventories where observed for the recharge sites (40%). 90 Sr behaved differently, showing similar inventories between reference and recharge site. We estimate that 75-89% of the total inventory of 137 Cs in the soil at the recharge site (7.000 Bq/m 2 ) originated from the fallout of the Chernobyl accident and from emissions of Swiss NPPs. This estimate is based on the

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

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)

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.

Review of behavior of plutonium in soils and other geologic materials

International Nuclear Information System (INIS)

Nishita, H.

1979-10-01

Available information on the physical and chemical reactions of Pu in soils and other geologic materials is reviewed. The primary intent of this review was to bring together information that may be helpful in assessing the movement and biological availability of Pu in terrestrial environment. The review is divided into two general categories, e.g., studies of chemical reactions of Pu in aqueous solutions and studies of Pu reactions in the more complex systems of soils and other geologic materials. The latter category is further divided into studies of Pu in materials that were freshly contaminated in the laboratory and of Pu in materials that had been contaminated in natural environments and had resided there for varying numbers of years. After the discussion of physical and chemical reactions of Pu, several reported examples of the actual movement of Pu in terrestrial environments are given

Material synthesis and evaluation of metrological characteristics of potassium fluozirconate certified reference material

Directory of Open Access Journals (Sweden)

D. G. Lisienko

2016-01-01

Full Text Available The relevance of the study. For metrological support of control methods for composition ofpotassium fluozirconate, used in the production of metallic zirconium, applied in various technical fields, including nuclear power, electronics, chemical engineering. The purpose: development of synthesis technology, and determination of metrological characteristics of certified reference material for composition ofpotassium fluozirconate (set, intended for metrological support of measuring element mass fraction: hafnium (Hf, silicon (Si, iron (Fe, aluminium (Al, chromium (Cr, tin (Sn, titanium (Ti in potassium fluozirconate. Research methods: X-ray diffraction, differential scanning colorimetry, thermogravimetric analysis, atomic-emission spectral analysis with arc excitation, mass spectral analysis, X-ray fluorescence analysis. Results. As a result of research a set of certified reference materials for composition of potassium fluozirconate is developed and produced. The CRM type is approved by Federal Agency on Technical Regulating and Metrology and registered in State Register of Approved Reference Material Types under number GSO 10593-2015.

Additive Manufacturing of Polyurethane Materials

Energy Technology Data Exchange (ETDEWEB)

Kunc, Vlastimil [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lindahl, John M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Minneci, Robert P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pyzik, Alek [Dow Chemical Company, Saginaw, MI (United States); Gorin, Craig [Dow Chemical Company, Midland, MI (United States); Allen, Sharon [Dow Chemical Company, Midland, MI (United States); Wilson, Keith [Dow Chemical Company, Midland, MI (United States); Howard, Kevin [Dow Chemical Company, Midland, MI (United States)

2017-08-10

ORNL worked with The DOW Chemical Company to validate the feasibility of 3D printing DOW’s polyurethane (PU) materials using ORNL’s equipment and know-how. This led to the development of the first directly-3D-printable PU material.

Study on behavior of Cs-137 and Pu-239, 240 in lake and marine environments on basis of sediment analysis

International Nuclear Information System (INIS)

Nagao, Seiya

1998-01-01

An investigation was made on the sediment mechanisms of artificial radioactive isotopes in relation to environmental factors through utilizing the differences in deposition behaviors of 137 Cs and 239,240 Pu. Cumulus deposit samples were collected from 4 lake and 7 ocean areas of different environmental and deposit conditions; oligotrophic, mesotrophic, acidtrophic and dystrophic lakes, and coastal and hemipelagic ocean areas. After purification of these deposit samples using ionchromatography, β-ray from 137 Cs and α-ray from Pu were spectroscopically determined to plat the respective concentration as a function of the depth in core. Based on the data of mean ratio of 239,240 Pu/ 137 Cs as to the organic sulfides and residual fractions and the total deposits, it was thought that when the ratio of Pu/Cs of lake deposits was higher than the fallout value, organic materials in the lake might be involved. Pu was mostly abundant in organic fractions compared with Cs, whereas Cs was present in all the four fractions of carbonates, oxides, organic materials and aluminosilicates. (M.N.)

Preparation of reference material for the measurement of natural radioactivity

International Nuclear Information System (INIS)

Ben Tekaya, Malik

2010-01-01

The objective of this work is to prepare reference material for the calibration of gamma spectrometry, alpha and XRF .Many procedures of chemical preparation and radiological analysis of a reference material from Triple Superphosphate were tested. Several techniques and methods of measurement were used. In addition to a description and validation of these procedures, a study of repeatability was conducted which resulted in a positive characterization of this material.

Homogeneity test of the ceramic reference materials for non-destructive quantitative

International Nuclear Information System (INIS)

Li Li; Fong Songlin; Zhu Jihao; Feng Xiangqian; Xie Guoxi; Yan Lingtong

2010-01-01

In order to study elemental composition of ancient porcelain samples, we developed a set of ceramic reference materials for non-destructive quantitative analysis. In this paper,homogeneity of Al, Si, K, Ca, Ti, Mn and Fe contents in the ceramic reference materials is investigated by EDXRF. The F test and the relative standard deviation are used to treat the normalized net counts by SPSS. The results show that apart from the DY2 and JDZ4 reference materials, to which further investigation would be needed, homogeneity of the DH, DY3, JDZ3, JDZ6, GY1, RY1, LQ4, YJ1, YY2 and JY2 meets the requirements of ceramic reference materials for non-destructive quantitative analysis. (authors)

Interaction of 238PuO2 heat sources with terrestrial and aquatic environments

International Nuclear Information System (INIS)

Patterson, J.H.; Nelson, G.B.; Matlack, G.M.; Waterbury, G.R.

1975-01-01

Radioisotope thermoelectric generators used in space missions are designed with a great factor of safety to ensure that they will withstand reentry from orbit and impact with the earth, and safely contain the nuclear fuel until it is recovered. Existing designs, utilizing 238 PuO 2 fuel, have proved more than adequately safe. More data about the interaction of this material with terrestrial and aquatic environments is continually being sought to predict the behavior of these heat sources in the extremely unlikely contact of these materials with the land or ocean. Terrestrial environments are simulated with large environmental chambers that permit control of temperature, humidity, and rainfall using different kinds of soils. Rain falling on thermally hot chunks of 238 PuO 2 causes the spallation of the surface of the fuel into extremely fine particles, as small as 50 nm, that are later transported downward through the soil. Some of the plutonia particles become agglomerated with soil particles. Plutonium transport is more significant during winter than during summer because evaporation losses from the soil are less in winter. Aquatic environments are simulated with large aquaria that provide temperature and aeration control. Earlier fuel designs that employed a plutonia-molybdenum cermet showed plutonium release rates of about 10 μCi/m 2 - s, referred to the total surface area of the cermet. Present advanced fuels, employing pure plutonium oxide, show release rates of about 20 nCi/m 2 - s in seawater and about 150 nCi/m 2 - s in freshwater. The temperature of these more advanced heat sources does not seem to affect the release rate in seawater. (auth)

Vivências de gestantes e puérperas com o diagnóstico do HIV

OpenAIRE

Araújo, Maria Alix Leite; Silveira, Cláudia Bastos da; Silveira, Caroline Bastos da; Melo, Simone Paes de

2008-01-01

Identificar as experiências de gestantes e puérperas portadoras do HIV com a quimioprofilaxia para prevenção da transmissão vertical. Estudo de abordagem qualitativa desenvolvido nos meses de março e abril de 2006 em uma maternidade de referência de Fortaleza-Ceará. Os sujeitos foram gestantes e puérperas HIV positivas em acompanhamento pré-natal e no alojamento conjunto. A coleta de dados deu-se através de entrevista e a análise em três categorias: a revelação do diagnóstico aos familiares, ...

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).

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

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

[The water content reference material of water saturated octanol].

Science.gov (United States)

Wang, Haifeng; Ma, Kang; Zhang, Wei; Li, Zhanyuan

2011-03-01

The national standards of biofuels specify the technique specification and analytical methods. A water content certified reference material based on the water saturated octanol was developed in order to satisfy the needs of the instrument calibration and the methods validation, assure the accuracy and consistency of results in water content measurements of biofuels. Three analytical methods based on different theories were employed to certify the water content of the reference material, including Karl Fischer coulometric titration, Karl Fischer volumetric titration and quantitative nuclear magnetic resonance. The consistency of coulometric and volumetric titration was achieved through the improvement of methods. The accuracy of the certified result was improved by the introduction of the new method of quantitative nuclear magnetic resonance. Finally, the certified value of reference material is 4.76% with an expanded uncertainty of 0.09%.

Magneto-electro-responsive material based on magnetite nanoparticles/polyurethane composites

International Nuclear Information System (INIS)

Petcharoen, Karat; Sirivat, Anuvat

2016-01-01

Multi-functional materials in actuator applications have been developed toward reversibility and sensitivity under various actuating fields. In this work, magneto-electro-responsive materials consisting of a polyurethane (PU) matrix and its composites embedded with magnetite nanoparticles (MNP) as a dispersed phase were fabricated to tailor the electromechanical properties and bending performance under electric, magnetic, and electromagnetic fields. Due to the superior characteristics of MNP over other magnetic materials, the composites fabricated with electronic polarization were highly responsive under electric field. The highest storage modulus sensitivity belonged to the 1.0% v/v MNP/PU composite which possessed the value of 3.46 at the electric field 2 kV mm"−"1. Moreover, all of the PU composites behaved as an electrostrictive material in which the stress depended quadratically on the electric field. It was demonstrated that the PU composites also possessed very good recoverability, fast response (< 15 s) and large bending angle relative to that of pristine PU under applied electric field. Interestingly, the steady state storage modulus response was attained within the first electrical actuation cycle and the PU composite was a fully reversible material. In addition, it was shown that superparamagnetism was a common characteristic of all fabricated composites under magnetic field. The 3.0%v/v MNP/PU composite provided the largest bending distance up to 23.60 mm, and 14.10 mm under the magnetic field of 5000 G, and the electromagnetic field of 320 G, respectively. In summary, the MNP/PU composite material is a potential candidate to be used as a smart material under the influences of electric and/or magnetic fields over other existing dielectric materials. - Highlights: • MNP/PU composites exhibit a superparamagnetic behavior. • MNP/PU composites show full reversibility under electric field. • 1.0% v/v MNP/PU composite provides the highest sensitivity

Magneto-electro-responsive material based on magnetite nanoparticles/polyurethane composites

Energy Technology Data Exchange (ETDEWEB)

Petcharoen, Karat; Sirivat, Anuvat, E-mail: anuvat.s@chula.ac.th

2016-04-01

Multi-functional materials in actuator applications have been developed toward reversibility and sensitivity under various actuating fields. In this work, magneto-electro-responsive materials consisting of a polyurethane (PU) matrix and its composites embedded with magnetite nanoparticles (MNP) as a dispersed phase were fabricated to tailor the electromechanical properties and bending performance under electric, magnetic, and electromagnetic fields. Due to the superior characteristics of MNP over other magnetic materials, the composites fabricated with electronic polarization were highly responsive under electric field. The highest storage modulus sensitivity belonged to the 1.0% v/v MNP/PU composite which possessed the value of 3.46 at the electric field 2 kV mm{sup −1}. Moreover, all of the PU composites behaved as an electrostrictive material in which the stress depended quadratically on the electric field. It was demonstrated that the PU composites also possessed very good recoverability, fast response (< 15 s) and large bending angle relative to that of pristine PU under applied electric field. Interestingly, the steady state storage modulus response was attained within the first electrical actuation cycle and the PU composite was a fully reversible material. In addition, it was shown that superparamagnetism was a common characteristic of all fabricated composites under magnetic field. The 3.0%v/v MNP/PU composite provided the largest bending distance up to 23.60 mm, and 14.10 mm under the magnetic field of 5000 G, and the electromagnetic field of 320 G, respectively. In summary, the MNP/PU composite material is a potential candidate to be used as a smart material under the influences of electric and/or magnetic fields over other existing dielectric materials. - Highlights: • MNP/PU composites exhibit a superparamagnetic behavior. • MNP/PU composites show full reversibility under electric field. • 1.0% v/v MNP/PU composite provides the highest

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

Preparation of reference material for organochlorine pesticides in a herbal matrix.

Science.gov (United States)

Wong, Yiu Chung; Wong, Siu Kay; Kam, Tat Ting

2008-12-01

The development of reference material for four organochlorine pesticides, namely hexachlorobenzene and three isomers of hexachlorocyclohexane (alpha-hexachlorocyclohexane, beta-hexachlorocyclohexane and gamma-hexachlorocyclohexane), in a ginseng root sample is presented. Raw materials (Panax ginseng) were purchased from a local market and confirmed to contain certain levels of incurred organochlorine pesticide residues by a validated gas chromatography-mass selective detection method. A total of more than 300 bottles each containing 25 g of samples were prepared after the materials had been freeze-dried, milled and thoroughly mixed. The homogeneity and stability of samples from randomly selected bottles were verified and the reference values were characterized using a highly precise isotope dilution gas chromatography-mass spectrometry (ID-GCMS) method that was recently developed by our laboratory. The purity of standard organochlorine chemicals was determined against certified reference materials to establish the accuracy of the ID-GCMS analysis. The concentrations (+/- expanded uncertainty) of hexachlorobenzene, alpha-hexachlorocyclohexane, beta-hexachlorocyclohexane and gamma-hexachlorocyclohexane in the reference material were 0.198 +/- 0.015, 0.450 +/- 0.022, 0.213 +/- 0.011 and 0.370 +/- 0.032 mg kg(-1), respectively. A portion (70 bottles) of the samples was also used in a proficiency testing (PT) scheme for assessing the testing capabilities of field laboratories. The consensus mean values of the PT obtained from the 70 participants were on the same order but deviated by -2.7 to -14.1% from those of the assigned reference values. Because of the wide spread of participants' data (relative standard deviation ranging from 44 to 56%), the PT results were not included in the calculation of the assigned values of the reference materials. The materials served as suitable reference materials to ascertain the quality control and validation processes for the

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

Certified reference materials for organic analysis

International Nuclear Information System (INIS)

QianChuanfan

2002-01-01

This presentation discusses the requirements for certified reference materials (CRMs) to be used in measurements of residues of pesticides in food and environmental samples. It deals with the types of CRMs, matrix selection, sample preparation and representativeness. It also discusses CRM validity period and gives some examples of CRM preparation

Immune reactivity of candidate reference materials

NARCIS (Netherlands)

Fernandez-Rivas, Montserrat; Aalbers, Marja; Fötisch, Kay; de Heer, Pleuni; Notten, Silla; Vieths, Stefan; van Ree, Ronald

2006-01-01

Immune reactivity is a key issue in the evaluation of the quality of recombinant allergens as potential reference materials. Within the frame of the CREATE project, the immune reactivity of the natural and recombinant versions of the major allergens of birch pollen (Bet v 1), grass pollen (Phl p 1

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)

New radiochemical methods for determination of 237Np a 241Pu using extraction chromatography (Presentation)

International Nuclear Information System (INIS)

Strisovska, J.

2013-01-01

Thesis was focused on the development of a new methodology for the separation of anthropogenic transuranium radionuclides 237 Np a 241 Pu from different kinds of matrices. The analytical methods used in this study were based on extraction chromatography and were optimized according to the sample type. The proposed radiochemical procedure is a combination of two algorithms, which represent the separation of radionuclides by using extraction chromatographic sorbents TEVA resin and TRU resin supplied by Eichrom Technologies LLC. 239 Np a 237 Np were selectively captured on sorbent TEVA resin in oxidation state 4+. TRU resin was used for purification of plutonium fraction from interfering americium radionuclide. 242 Pu and 239 Np radionuclides as tracers have been used to monitor the radiochemical yields of separation. Before every radiochemical separation tracer radionuclide 239 Np was obtained by separation from the parent radionuclide 2 43 Am, which is in radioactive equilibrium to 239 Np. The average yield of chemical separation was 69,3% for 239 Np at 277 keV energy line and 65,9% at 228 keV energy line. The NPL AH-B08069 (2008) samples which consist of the mixture of alpha-radionuclides were used for the modification and optimization of separation method used for separation of Np and Pu in model samples. This method provided high radiochemical yields of 239,240 Pu (95,0 ± 3,5)% and 237 Np (87,9 ± 3,0)%.. Reliability of the method was verified by applying our modified separation procedures on reference materials IAEA-375 and IAEA-414 supplied by International Atomic Energy Agency. A good agreement between the results is obtained by this procedure and the certified values were found. Samples of contaminated soils from the area of Nuclear power plant A-1 Jaslovske Bohunice which is stored temporarily before disposal were analyzed using developed separation procedure. Specific activity of investigated radionuclides was determined in these samples. (author)

Evaluation of a reference material for glycated haemoglobin

NARCIS (Netherlands)

Weykamp, CW; Penders, TJ; Muskiet, FAJ; vanderSlik, W

The use of lyophilized blood as a reference material for glycated haemoglobin was investigated with respect to IFCC criteria for calibrators and control materials. Ninety-two laboratories, using 11 methods, detected no changes in glycated haemoglobin content when the lyophilizate was stored for one

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

An in-house usage assessment of print reference materials in a ...

African Journals Online (AJOL)

The study investigated the utilization of print reference materials in a Nigerian hybrid medical school library, factors influencing utilization or under utilization, and if utilization commensurate with the library's prospect on the use of these materials. During the period of study, it was assumed that all reference materials pulled ...

Standard Reference Development of nuclear material for Tensile and Hardness Test Properties

International Nuclear Information System (INIS)

Choo, Y. S.; Kim, D. S.; Yoo, B. O.; Ahn, S. B.; Baik, S. J.; Chun, Y. B.; Kim, K. H.; Hong, K. P.; Ryu, W. S.

2007-12-01

Standard reference is a official approved data such a coefficient of physics, approved material properties, and etc., which should be analyzed and evaluated by scientific method to acquire official approval for accuracy and credibility of measured data and information. So it could be used broadly and continuously by various fields of nation and society. It is classified to effective standard reference, verified standard reference, and certified standard reference. There are sixteen fields in designated standard references such a physical chemistry field, material field, metal field, and the others. The standard reference of neutron irradiated nuclear structural material is classified to metal field. This report summarized the whole processes about data collection, data production, data evaluation and the suggestion of details evaluation technical standard for tensile and hardness properties, which were achieved by carry out the project 'nuclear material standard reference development' as a result

Standard Reference Development of nuclear material for Tensile and Hardness Test Properties

Energy Technology Data Exchange (ETDEWEB)

Choo, Y. S.; Kim, D. S.; Yoo, B. O.; Ahn, S. B.; Baik, S. J.; Chun, Y. B.; Kim, K. H.; Hong, K. P.; Ryu, W. S

2007-12-15

Standard reference is a official approved data such a coefficient of physics, approved material properties, and etc., which should be analyzed and evaluated by scientific method to acquire official approval for accuracy and credibility of measured data and information. So it could be used broadly and continuously by various fields of nation and society. It is classified to effective standard reference, verified standard reference, and certified standard reference. There are sixteen fields in designated standard references such a physical chemistry field, material field, metal field, and the others. The standard reference of neutron irradiated nuclear structural material is classified to metal field. This report summarized the whole processes about data collection, data production, data evaluation and the suggestion of details evaluation technical standard for tensile and hardness properties, which were achieved by carry out the project 'nuclear material standard reference development' as a result.

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)

Certification of biological candidates reference materials by neutron activation analysis

Science.gov (United States)

Kabanov, Denis V.; Nesterova, Yulia V.; Merkulov, Viktor G.

2018-03-01

The paper gives the results of interlaboratory certification of new biological candidate reference materials by neutron activation analysis recommended by the Institute of Nuclear Chemistry and Technology (Warsaw, Poland). The correctness and accuracy of the applied method was statistically estimated for the determination of trace elements in candidate reference materials. The procedure of irradiation in the reactor thermal fuel assembly without formation of fast neutrons was carried out. It excluded formation of interfering isotopes leading to false results. The concentration of more than 20 elements (e.g., Ba, Br, Ca, Co, Ce, Cr, Cs, Eu, Fe, Hf, La, Lu, Rb, Sb, Sc, Ta, Th, Tb, Yb, U, Zn) in candidate references of tobacco leaves and bottom sediment compared to certified reference materials were determined. It was shown that the average error of the applied method did not exceed 10%.

Certification of a new biological reference material - Virginia Tobacco Leaves (CTA-VTL-2) and homogeneity study by NAA on this and other candidate reference materials

International Nuclear Information System (INIS)

Dybczynski, Rajmund; Polkowska-Motrenko, Halina; Samczynski, Zbigniew; Szopa, Zygmunt; Kulisa, Krzysztof; Wasek, Marek

2002-01-01

This report describes the laboratory's participation in the interlaboratory comparison run where the laboratory applied neutron activation analysis aimed at certification of the candidate reference material. Data evaluation and statistical treatment steps are discussed. The report also describes homogeneity study on the reference material and provides details of the analytical procedures

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...

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.

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

A new basaltic glass microanalytical reference material for multiple techniques

Science.gov (United States)

Wilson, Steve; Koenig, Alan; Lowers, Heather

2012-01-01

The U.S. Geological Survey (USGS) has been producing reference materials since the 1950s. Over 50 materials have been developed to cover bulk rock, sediment, and soils for the geological community. These materials are used globally in geochemistry, environmental, and analytical laboratories that perform bulk chemistry and/or microanalysis for instrument calibration and quality assurance testing. To answer the growing demand for higher spatial resolution and sensitivity, there is a need to create a new generation of microanalytical reference materials suitable for a variety of techniques, such as scanning electron microscopy/X-ray spectrometry (SEM/EDS), electron probe microanalysis (EPMA), laser ablation inductively coupled mass spectrometry (LA-ICP-MS), and secondary ion mass spectrometry (SIMS). As such, the microanalytical reference material (MRM) needs to be stable under the beam, be homogeneous at scales of better than 10–25 micrometers for the major to ultra-trace element level, and contain all of the analytes (elements or isotopes) of interest. Previous development of basaltic glasses intended for LA-ICP-MS has resulted in a synthetic basaltic matrix series of glasses (USGS GS-series) and a natural basalt series of glasses (BCR-1G, BHVO-2G, and NKT-1G). These materials have been useful for the LA-ICP-MS community but were not originally intended for use by the electron or ion beam community. A material developed from start to finish with intended use in multiple microanalytical instruments would be useful for inter-laboratory and inter-instrument platform comparisons. This article summarizes the experiments undertaken to produce a basalt glass reference material suitable for distribution as a multiple-technique round robin material. The goal of the analytical work presented here is to demonstrate that the elemental homogeneity of the new glass is acceptable for its use as a reference material. Because the round robin exercise is still underway, only

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

Element content and particle size characterization of a mussel candidate reference material

International Nuclear Information System (INIS)

Moreira, Edson G.; Vasconcellos, Marina B.A.; Santos, Rafaela G. dos; Martinelli, Jose R.

2011-01-01

The use of certified reference materials is an important tool in the quality assurance of analytical measurements. To assure reliability on recently prepared powder reference materials, not only the characterization of the property values of interest and their corresponding uncertainties, but also physical properties such as the particle size distribution must be well evaluated. Narrow particle size distributions are preferable than larger ones; as different size particles may have different analyte content. Due to this fact, the segregation of the coarse and the fine particles in a bottle may lead to inhomogeneity of the reference material, which should be avoided. In this study the element content as well as the particle size distribution of a mussel candidate reference material produced at IPEN-CNEN/SP was investigated. Instrumental Neutron Activation Analysis was applied to the determination of 15 elements in seven fractions of the material with different particle size distributions. Subsamples of the materials were irradiated simultaneously with elemental standards at the IEA-R1 research nuclear reactor and the induced gamma ray energies were measured in a hyperpure germanium detector. Three vials of the candidate reference material and three coarser fractions, collected during the preparation, were analyzed by Laser Diffraction Particle Analysis to determine the particle size distribution. Differences on element content were detected for fractions with different particle size distribution, indicating the importance of particle size control for biological reference materials. From the particle size analysis, Gaussian particle size distribution was observed for the candidate reference material with mean particle size μ = 94.6 ± 0.8 μm. (author)

Preparation and certification of rice flour reference materials for trace elements analysis

International Nuclear Information System (INIS)

Cho, Kyung Haeng; Park, Chang Joon; Woo, Jin Choon; Suh, Jung Ki; Han, Myung Sub; Lee, Jong Hae

1998-01-01

Rice flour reference materials were prepared from the unpolished rice grown in korea and certified for elemental composition. The reference materials consist of two samples containing normal and high level. The reference material at elevated level was prepared by spiking to the normal rice flour six toxic elements of As, Cd, Cu, Cr, Hg, Pb with 1.0μg/g on a dry weight basis. Homogeneity of the prepared materials was evaluated through the determination of Ca, Cu, Fe, Mn, Zn by instrumental neutron activation analysis (INAA) and atomic absorption spectrometry (AAS). Small variance of elemental composition among inter-bottled samples assured homogeneity of the prepared materials. The materials were decomposed by high pres-sure digestion and microwave digestion method. INAA, AAS, inductively coupled plasma-atomic absorption spectrometry (ICP-AES), ICP-mass spectrometry (MS) and vapour generation techniques were employed to analyze the reference materials. From this independent analytical results, the certified or reference values are determined for As, Ca, Cd, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, P, Pb, Se, Zn

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

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.)

Acceptable knowledge summary report for combustible/noncombustible, metallic, and HEPA filter waste resulting from 238Pu fabrication activities

International Nuclear Information System (INIS)

Rogers, P.S.Z.; Foxx, C.L.

1998-01-01

All transuranic (TRU) waste must be sufficiently characterized and certified before it is shipped to the Waste Isolation Pilot Plant (WIPP). The US Environmental Protection Agency (EPA) allows use of acceptable knowledge (AK) for waste characterization. EPA uses the term AK in its guidance document and defines AK and provides guidelines on how acceptable knowledge should be obtained and documented. This AK package has been prepared in accordance with Acceptable Knowledge Documentation (TWCP-QP-1.1-021,R.2). This report covers acceptable knowledge information for five waste streams generated at TA-55 during operations to fabricate various heat sources using feedstock 238 Pu supplied by the Savannah River Site (SRS). The 238 Pu feedstock itself does not contain quantities of RCRA-regulated constituents above regulatory threshold limits, as known from process knowledge at SRS and as confirmed by chemical analysis. No RCRA-regulated chemicals were used during 238 Pu fabrication activities at TA-55, and all 238 Pu activities were physically separated from other plutonium processing activities. Most of the waste generated from the 238 Pu fabrication activities is thus nonmixed waste, including waste streams TA-55-43, 45, and 47. The exceptions are waste streams TA-55-44, which contains discarded lead-lined rubber gloves used in the gloveboxes that contained the 238 Pu material, and TA-55-46, which may contain pieces of discarded lead. These waste streams have been denoted as mixed because of the presence of the lead-containing material

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

Low and intermediate level waste in SFR-1. Reference Waste Inventory 2007

Energy Technology Data Exchange (ETDEWEB)

Almkvist, Lisa (Vattenfall Power Consultant AB, Stockholm (SE)); Gordon, Anna (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE))

2007-11-15

The objective with this report is to describe all the waste and the waste package that is expected to be deposited in SFR 1 at the time of closure. The report will form the basis for the release calculation in the safety analysis for SFR 1. Three different scenarios are explored in this report; the waste inventory is based on an estimated operational lifetime of the Swedish nuclear power plants of 50 and 60 years and that closure of the SFR 1 repository will take place in 2040 or 2050 respectively. The third scenario is where the repository is full (one part where the activity adds up to 1016 Bq and one part where the repository is considered full regarding volume). In the report, data about geometries, weights, materials, chemicals and radionuclide are given. No chemotoxic material has been identified in the waste. The inventory is estimated using the Prosit-interface which extracts information from the Triumf database. The inventory is based on so called 'waste types' and the waste types' 'reference waste package'. The reference waste package combined with a prognosis of the number of waste packages to be delivered to SFR 1 gives the final waste inventory for SFR 1. All reference waste packages are thoroughly described in the appendices of this report. The reference waste packages are as far as possible based on actual experiences and measurements. The radionuclide inventory is also based on actual measurements. The inventory is based on measurements of 60Co and 137Cs in waste packages and on measurements of 239Pu and 240Pu in reactor water. Other nuclides in the inventory are calculated with correlation factors

Micro-homogeneity evaluation of a bovine kidney candidate reference material

Energy Technology Data Exchange (ETDEWEB)

Castro, Liliana; Moreira, Edson G.; Vasconcellos, Marina B.A., E-mail: lcastroesnal@usp.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

2017-07-01

The minimum sample intake for which a reference material remains homogeneous is one of the parameters that must be estimated in the homogeneity assessment study of reference materials. In this work, Instrumental Neutron Activation Analysis was used to evaluate this quantity in a bovine kidney candidate reference material. The mass fractions of 9 inorganic constituents were determined in subsamples between 1 and 2 mg in order to estimate the relative homogeneity factor (HE) and the minimum sample mass to achieve 5% and 10% precision on a 95% confidence level. Results obtained for H{sub E} in all the analyzed elements were satisfactory. The estimated minimum sample intake was between 2 mg and 40 mg, depending on the element. (author)

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

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

Characterization of nanoparticles as candidate reference materials

International Nuclear Information System (INIS)

Martins Ferreira, E.H.; Robertis, E. de; Landi, S.M.; Gouvea, C.P.; Archanjo, B.S.; Almeida, C.A.; Araujo, J.R. de; Kuznetsov, O.; Achete, C.A.

2013-01-01

We report the characterization of three different nanoparticles (silica, silver and multi-walled carbon nanotubes) as candidate reference material. We focus our analysis on the size distribution of those particles as measured by different microscopy techniques. (author)

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

The Raman fingerprint of plutonium dioxide: Some example applications for the detection of PuO2 in host matrices

NARCIS (Netherlands)

Manara, D; Naji, M.; Mastromarino, S.; Elorrieta, J. M.; Magnani, Nicola; Martel, L.; Colle, J-Y

2018-01-01

Some example applications are presented, in which the peculiar Raman fingerprint of PuO₂ can be used for the detection of crystalline Pu⁴⁺ with cubic symmetry in an oxide environment in various host materials, like mixed oxide fuels, inert matrices and corium sub-systems.

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

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

Absorbed Internal Dose Conversion Coefficients for Domestic Reference Animals and Plant

Energy Technology Data Exchange (ETDEWEB)

Keum, Dong Kwon; Jun, In; Lim, Kwang Muk; Choi, Yong Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2010-02-15

This paper describes the methodology of calculating the internal dose conversion coefficient in order to assess the radiological impact on non-human species. This paper also presents the internal dose conversion coefficients of 25 radionuclides ({sup 3}H, {sup 7}Be, {sup 14}C, {sup 40}K, {sup 51}Cr, {sup 54}Mn, {sup 59}Fe, {sup 58}Co, {sup 60}Co, {sup 65}Zn, {sup 90}Sr, '9{sup 5}Zr, {sup 95}Nb, {sup 99}Tc, {sup 106}Ru, {sup 129}I, {sup 131}I, {sup 136}Cs, {sup 137}Cs, {sup 140}Ba, {sup 140}La, {sup 144}Ce, {sup 238}U, {sup 239}Pu, {sup 240}Pu) for domestic seven reference animals (roe deer, rat, frog, snake, Chinese minnow, bee, and earthworm) and one reference plant (pine tree). The uniform isotropic model was applied in order to calculate the internal dose conversion coefficients. The calculated internal dose conversion coefficient (muGyd{sup -1} per Bqkg{sup -1}) ranged from 10{sup -6} to 10{sup -2} according to the type of radionuclides and organisms studied. It turns out that the internal does conversion coefficient was higher for alpha radionuclides, such as {sup 238}U, {sup 239}Pu, and {sup 240}Pu, and for large organisms, such as roe deer and pine tree. The internal dose conversion coefficients of {sup 239}Pu, {sup 240}Pu, {sup 238}U, {sup 14}C, {sup 3}H and {sup 99}Tc were independent of the organism

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)

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)

Production and certification of reference materials

International Nuclear Information System (INIS)

Sarkis, Jorge Eduardo de S.; Kakazu, Mauricio H.; Hespanhol, Emilio Carlos B.; Martins, Elaine Arantes J.

1996-01-01

The reference materials used in analytical chemistry permit us to evaluate correctly the analytical producers as well as experimental set up. U 3 O 8 was produced at IPEN to be used as a secondary standard. We present the first results on U 3 O 8 and discuss the method, preparation, and characterization of that oxide. (author)

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.

Results of 90Sr and 239+240Pu, 238Pu, 241Am measurements in some samples of mushrooms and forest soil from Poland

International Nuclear Information System (INIS)

Mietelski, J.W.; Larosa, J.; Ghods, A.

1992-01-01

Strontium-90, plutonium and americium activity concentrations in a few samples of forest soils, some species of mushrooms and fern leaves were determined. These results are compared with caesium activity concentrations in the same materials obtained in a previous work. Radiochemical procedures are described. The origin of the contamination (Chernobyl accident or nuclear test explosion release) is discussed. The 90 Sr activity concentration ranges from 0.6 Bq/kg (mushroom samples) to 48.4 Bq/kg (fern leaves). For 239+240 Pu, it ranges from not detected above background (mushrooms, fern) to 10.8 Bq/kg (humus layer of forest soil). The maximum concentration of 241 Am is found to be 2.4 Bq/kg (humus sample) and for 238 Pu it is 0.85 Bq/kg (also in the humus sample). (author). 12 refs, 9 figs, 7 tabs

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.

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)

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

Biological and environmental reference materials for trace elements, nuclides and organic microcontaminants

International Nuclear Information System (INIS)

Cortes Toro, E.; Parr, R.M.; Clements, S.A.

1990-01-01

This report has been produced from a database on analytical reference materials of biological and environmental origin, which is maintained at the International Atomic Energy Agency. It is an updated version of an earlier report, published in 1985, which focussed mainly on reference materials for trace elements. In the present version of the report, reference materials for trace elements still constitute the major part of the data; however, information is also now included on a number of other selected analytes of relevance to IAEA programmes, i.e. radionuclides, stable isotopes and organic microcontaminants. The database presently contains 2,694 analyte values for 117 analytes in 116 biological and 77 environmental (non-biological) reference materials produced by 20 different suppliers. Additional information on the cost of the material, the unit size supplied, (weight or volume), and the minimum weight of material recommended for analysis is also provided (if available to the authors). It is expected that this report will help analysts to select the reference material that matches as closely as possible, with respect to matrix type and concentrations of the analytes of interest, the ''real'' samples that are to be analysed. Refs, 12 tabs

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.)

The biochemical mechanisms responsible for differences in the half-life of monomeric 239Pu in rat and Syrian hamster liver

International Nuclear Information System (INIS)

Seidel, A.; Winter, R.; Jentzsch, C.; Gruner, R.; Heumann, H.G.; Hanke, S.

1979-01-01

The subcellular distribution of 239 Pu citrate in rat and Syrian hamster liver was studied with the help of the non-ionic detergent Triton WR1339, used as method for separating lysosomes from other cell organelles. Triton WR1339 was injected six days after 239 Pu and the animals were sacrificed after Day 10. Liver homogenates were subjected to differential and isopycnic centrifugation in sucrose gradients. In both animal species 90% of 239 Pu of the post-nuclear supernatant was found in the fraction containing mitochondria, lysosomes, endoplasmatic reticulum and ferritin. Triton WR1339 injection caused a concomitant shift of the lysosomal marker acid phosphatase and of 239 Pu from high densities to rho approximately 1.10 in both animal species. According to our results, binding of 239 Pu to mitochondria and peroxisomes can be excluded, and association to endoplasmatic reticulum and plasma membranes is not very probable. We must consider the possibility that a part of the radioactivity occurring at rho approximately 1.10 can also be bound to ferritin. According to these findings, lysosomes could be one of the main storage sites for 239 Pu in both species. From studies on the pharmacokinetics of 3 H-labelled Triton WR1339 and on the behaviour of Triton-filled rat liver lysosomes, which are also presented in the paper, it is tentatively concluded that the rapid excretion of 239 Pu from rat liver is due to the normally rapid elimination of lysosomal material from hepatocytes into the bile in this species. In Syrian hamsters the fate of lysosomal material in liver may be different or redistribution of 239 Pu occurs at a later time. (author)

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)

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)

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.

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.

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

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

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

Pu abundances, concentrations, and isotopics by x- and gamma-ray spectrometry assay techniques

International Nuclear Information System (INIS)

Camp, D.C.; Gunnink, R.; Ruhter, W.D.; Prindle, A.L.; Gomes, R.J.

1986-01-01

Two x- and gamma-ray systems were recently installed at-line in gloveboxes and will measure Pu solution concentrations from 5 to 105 g/L. These NDA technique, developed and refined over the past decade, are now used domestically and internationally for nuclear material process monitoring and accountability needs. In off- and at-line installations, they can measure solution concentrations to 0.2%. The K-XRFA systems use a transmission source to correct for solution density. The gamma-ray systems use peaks from 59- to 208-keV to determine solution concentrations and relative isotopics. A Pu check source monitors system stability. These two NDA techniques can be combined to form a new, NDA measurement methodology. With the instrument located outside of a glovebox, both relative Pu isotopics and absolute Pu abundances of a sample located inside a glovebox can be measured. The new technique works with either single or dual source excitation; the former for a detector 6 to 20 cm away with no geometric corrections needed; the latter requires geometric corrections or source movement if the sample cannot be measured at the calibration distance. 4 refs., 7 figs., 2 tabs

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

Measuring Pu in a glove box using portable NaI and germanium detectors

International Nuclear Information System (INIS)

Hankins, D.E.

1984-01-01

A NaI crystal or germanium detector inside a portable lead shield can determine the amount of plutonium in a glove box. The number of counts required are defined and the locations outside the box where the detector needs to be positioned are given. The calculated accuracy for measuring the Pu when these locations are used is within +/-30% for most glove boxes. Other factors that may affect this accuracy, such as γ-ray absorption by glove-box materials, self-absorption by Pu, absorption by equipment in the glove box, and the limits of the counting equipment are also discussed

Gravimetric determination of carbon in uranium-plutonium carbide materials

International Nuclear Information System (INIS)

Kavanaugh, H.J.; Dahlby, J.W.; Lovell, A.P.

1979-12-01

A gravimetric method for determining carbon in uranium-plutonium carbide materials was developed to analyze six samples simultaneously. The samples are burned slowly in an oxygen atmosphere at approximately 900 0 C, and the gases generated are passed through Schuetze's oxidizing reagent (iodine pentoxide on silica gel) to assure quantitative oxidation of the CO to CO 2 . The CO 2 is collected on Ascarite and weighed. This method was tested using a tungsten carbide reference material (NBS-SRM-276) and a (U,Pu)C sample. For 42 analyses of the tungsten carbide, which has a certified carbon content of 6.09%, an average value of 6.09% was obtained with a standard deviation of 0.01 7 % or a relative standard deviation of 0.28%. For 17 analyses of the (U,Pu)C sample, an average carbon content of 4.97% was found with a standard deviation of 0.01 2 % or a relative standard deviation of 0.24%

Preparation and certification of reference materials for the nuclear industry

International Nuclear Information System (INIS)

Wagner, J.F.

1994-01-01

CETAMA (Commission for the Establishment of Analytical Methods) of the Cea group is producing and certifying uranium and plutonium reference materials to meet the requirements of analytical laboratories in the nuclear industry. Reference materials are required at all stages in the fuel cycle: from extraction of uranium, purification, conversion, uranium enrichment, fuel fabrication until reprocessing of spent fuel, management and storage of waste. 3 tabs

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

Radiolysis of Salts and Long-Term Storage Issues for Both Pure and Impure PuO{sub 2} Materials in Plutonium Storage Containers

Energy Technology Data Exchange (ETDEWEB)

Lav Tandon

2000-05-01

The Material Identification and Surveillance (MIS) project sponsored a literature search on the effects of radiation on salts, with focus on alkali chlorides. The goal of the survey was to provide a basis for estimating the magnitude of {alpha} radiation effects on alkali chlorides that can accompany plutonium oxide (PuO{sub 2}) into storage. Chloride radiolysis can yield potentially corrosive gases in plutonium storage containers that can adversely affect long-term stability. This literature search was primarily done to provide a tutorial on this topic, especially for personnel with nonradiation chemistry backgrounds.

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

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.

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

Development studies of captopril certified reference material

Directory of Open Access Journals (Sweden)

Raquel Nogueira

2011-06-01

Full Text Available This paper describes the studies performed with the candidate Certified Reference Material (CRM of captopril, the first CRM of an active pharmaceutical ingredient (API in Brazil, including determination of impurities (organic, inorganic and volatiles, homogeneity testing, short- and long-term stability studies, calculation of captopril content using the mass balance approach, and estimation of the associated measurement uncertainty.Este artigo descreve os estudos realizados com o candidato a Material de Referência Certificado (MRC de captopril, primeiro MRC de fármacos no Brasil, incluindo a determinação de impurezas (orgânicas, inorgânicas e voláteis, testes de homogeneidade, testes de estabilidade de curta e longa duração, cálculo do teor de captopril por balanço de massa e estimativa da incerteza de medição associada ao valor certificado.

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

Analytical representation of the thermal conductivity and electrical resistivity of UC/sub 1 +- x/, PuC/sub 1-x/, and (U/sub y/Pu/sub 1-y/)C/sub 1 +- x/

International Nuclear Information System (INIS)

Storms, E.K.

1982-12-01

This report uses selected measurements from the literature to construct analytical expressions that describe the electrical and thermal conductivity of pure, high-density UC/sub 1 +- x/, PuC/sub 1-x/, and (U/sub y/Pu/sub 1-y/C/sub 1 +- x/ as a function of x,y, and temperature. The approach shows that many of the differences between the reported measurements can be resolved if the carbon cntent of the single-phase material is taken into account. Analytical expressions are also given that describe the temperature variation of the phase boundaries for these phases. 16 figures

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

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

Standard and reference materials for environmental science. Part 1. Technical memo

Energy Technology Data Exchange (ETDEWEB)

Cantillo, A.Y.

1995-11-01

This is the fourth edition of the catalog of reference materials suited for use in environmental science, originally compiled in 1986 for NOAA, IOC, and UNEP. The catalog lists more than 1200 reference materials from 28 producers and contains information about their proper use, sources, availability, and analyte concentrations. Indices are included for elements, isotopes, and organic compounds, as are cross references to CAS registry numbers, alternate names, and chemical structures of selected organic compounds.

Standard and reference materials for environmental science. Part 2. Technical memo

Energy Technology Data Exchange (ETDEWEB)

Cantillo, A.Y.

1995-11-01

This is the fourth edition of the catalog of reference materials suited for use in environmental science, originally compiled in 1986 for NOAA, IOC, and UNEP. The catalog lists more than 1200 reference materials from 28 producers and contains information about their proper use, sources, availability, and analyte concentrations. Indices are included for elements, isotopes, and organic compounds, as are cross references to CAS registry numbers, alternate names, and chemical structures of selected organic compounds.

Enhancement of relaxation rates in the normal state of superconductor PuRhGa5:NQR relaxation study

International Nuclear Information System (INIS)

Sakai, H.; Kambe, S.; Tokunaga, Y.; Fujimoto, T.; Walstedt, R.E.; Yasuoka, H.; Aoki, D.; Homma, Y.; Yamamoto, E.; Nakamura, A.; Shiokawa, Y.; Nakajima, K.; Arai, Y.; Matsuda, T.D.; Haga, Y.; Onuki, Y.

2007-01-01

The spin-lattice relaxation rates (1/T 1 ) have been measured under zero field using nuclear quadrupole resonance (NQR) lines in superconductor PuRhGa 5 and Pauli-paramagnet LuCoGa 5 . In the reference LuCoGa 5 with fully-occupied 4f shell, the 1/T 1 shows the constant behavior of (T 1 T) -1 =0.495+/-0.002(sK) -1 . On the other hand, in PuRhGa 5 , 1/T 1 is much larger than in LuCoGa 5 and the 1/T 1 ∝T behavior below ∼30K is seen, where its (T 1 T) -1 value is 3.27+/-0.005(sK) -1 . These results suggest a development of coherent Fermi liquid state incorporated with 5f electrons below ∼30K in PuRhGa 5

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)

Standard reference materials analysis for MINT Radiocarbon Laboratory

International Nuclear Information System (INIS)

Noraishah Othman; Kamisah Alias; Nasasni Nasrul

2004-01-01

As a follow-up to the setting up of the MINT Radiocarbon Dating facility. an exercise on the IAEA standard reference materials was carried out. Radiocarbon laboratories frequently used these 8 natural samples to verify their systems. The materials were either pretreated or analysed directly to determine the activity of 14 C isotopes of the five samples expressed in % Modern (pMC) terms and to make recommendations on further use of these materials. We present the results of the five materials and discuss the analyses that were undertaken. (Author)