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Sample records for cs sr ra

  1. Distribution of Natural (U-238, Th-232, Ra-226) and Technogenic (Sr-90, Cs-137) Radionuclides in Soil-Plants Complex Near Issyk-Kul Lake, Kyrgyzstan

    Science.gov (United States)

    Jovanovic, L.; Kaldybaev, B.; Djenbaev, B.; Tilenbaev, A.

    2012-04-01

    Researches on radionuclides distribution in the soil-plants complex provide essential information in understanding human exposure to natural and technogenic sources of radiation. It is necessary in establishing regulation relating to radiation protection. The aim of this study was the radiochemical analysis of the content natural radionuclides 238U, 232Th,226Ra and technogenic radionuclides content (90Sr, 137Cs) in soils near Issyk-Kul lake (Kyrgyzstan). Results of radiochemical analyses have shown, that the concentrations of thorium-232 are fluctuating in the limits (11.7-84.1)-10-4% in the soils. The greatest concentration of thorium-232 has been found in the light chestnut soils. The content of uranium-238 in the soils near Issyk-Kul lake is fluctuating from 2.8 up to 12.7-10-4%. Radium-226 has more migration ability in comparison with other heavy natural radionuclides. According to our research the concentrations of radium-226 are fluctuating in the limits (9.4-43.0)-10-11%. The greatest concentration of radium-226 (43,0±2,8)-10-11% has been determined in the light chestnut soil. In connection with global migration of contaminating substances, including radioactive, the special attention is given long-lived radionuclides strontium-90 and caesium-137 in food-chains, and agroecosystems. Results of radiochemical analyses have shown, that specific activity of strontium-90 is fluctuating in the range of 2.9 up to 11.1 Bq/kg, and caesium-137 from 3.7 up to 14,3 Bq/kg in the soil of agroecosystems in the region of Issyk-Kul. In soil samples down to 1 meter we have observed vertical migration of these radionuclides, they were found to accumulate on the surface of soil horizon (0-5 cm) and their specific activity sharply decreases with depth. In addition in high-mountain pastures characterized by horizontal migration of cattle in profiles of soil, it was discovered that specific activity of radionuclides are lower on the slope than at the foot of the mountain. The

  2. Geochemical Speciation of Soil 7Be,137Cs,226Ra and 228Ra as Tracers to Particle Trnsport

    Institute of Scientific and Technical Information of China (English)

    BALZHANGUO; WANGUOJIANG; 等

    1997-01-01

    A brunisolic soil collected from an erosive forest land(HF-1-1) and a yellow soil from and accumulative shallow basin(HF-6-1) in the watershed of Lake Hongfeng (HF) were used for activity measurements of 7Be,137Cs,226Ra and 228Ra in different geochemical speciation.More than 85% of 7Be,137Cs,226Ra and 228Ra in the soils were bound to organic Fe-Mn oxy-hydroxide and residual fractions.They could move with soil particlesw and be used as tracers for the erosion and /or accumulation of soil particles.7Be gohemical specition in the soils agreed with its trace for seasonal particle transport.137Cs geohemial speciaiton was suitable for tracing soil particle accumulation and for sediment aating.226Ra and 228Ra were ombined in crystalline skeleton of clay minerals and mainly remained as residues in the soils and little was bound to the soluble,exchangeable and carbonate fractions.The differentiation of 226 Ra/228Ra activity ratios in different geoheical fractions in the soils could be used as a parameter to trace accumulation and /or erosion of soil particles.

  3. Encapsulation of Cs/Sr contaminated clinoptilolite in geopolymers produced from metakaolin

    Energy Technology Data Exchange (ETDEWEB)

    Kuenzel, C., E-mail: c.kuenzel08@imperial.ac.uk [Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW72AZ (United Kingdom); Centre for Advanced Structural Ceramics, Department of Materials, Imperial College London, South Kensington Campus, London SW72AZ (United Kingdom); Cisneros, J.F. [Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW72AZ (United Kingdom); Neville, T.P. [Centre for CO_2 Technology, Department of Chemical Engineering, University College London, Gower Street, London WC1E6JE (United Kingdom); Vandeperre, L.J. [Centre for Advanced Structural Ceramics, Department of Materials, Imperial College London, South Kensington Campus, London SW72AZ (United Kingdom); Simons, S.J.R.; Bensted, J. [Centre for CO_2 Technology, Department of Chemical Engineering, University College London, Gower Street, London WC1E6JE (United Kingdom); Cheeseman, C.R. [Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW72AZ (United Kingdom)

    2015-11-15

    The encapsulation of caesium (Cs) and strontium (Sr) contaminated clinoptilolite in Na and K based metakaolin geopolymers is reported. When Cs or Sr loaded clinoptilolite is mixed with a metakaolin geopolymer paste, the high pH of the activating solution and the high concentration of ions in solution cause ion exchange reactions and dissolution of clinoptilolite with release of Cs and Sr into the geopolymer matrix. The leaching of Cs and Sr from metakaolin-based geopolymer has therefore been investigated. It was found that Na-based geopolymers reduce leaching of Cs compared to K-based geopolymers and the results are in agreement with the hard and soft acids and bases (HSAB) theory. Cs ions are weak Lewis acids and aluminates are a weak Lewis base. During the formation of the geopolymer matrix Cs ions are preferentially bound to aluminate phases and replace Na in the geopolymer structure. Sr uptake by Na-geopolymers is limited to 0.4 mol Sr per mole of Al and any additional Sr is immobilised by the high pH which causes precipitation of Sr as low solubility hydroxide and carbonate phases. There was no evidence of any other phases being formed when Sr or Cs are added to metakaolin geopolymers. - Highlights: • Leaching. • Encapsulation of Cs and Sr. • Nuclear waste. • Clinoptilolite.

  4. Encapsulation of Cs/Sr contaminated clinoptilolite in geopolymers produced from metakaolin

    Science.gov (United States)

    Kuenzel, C.; Cisneros, J. F.; Neville, T. P.; Vandeperre, L. J.; Simons, S. J. R.; Bensted, J.; Cheeseman, C. R.

    2015-11-01

    The encapsulation of caesium (Cs) and strontium (Sr) contaminated clinoptilolite in Na and K based metakaolin geopolymers is reported. When Cs or Sr loaded clinoptilolite is mixed with a metakaolin geopolymer paste, the high pH of the activating solution and the high concentration of ions in solution cause ion exchange reactions and dissolution of clinoptilolite with release of Cs and Sr into the geopolymer matrix. The leaching of Cs and Sr from metakaolin-based geopolymer has therefore been investigated. It was found that Na-based geopolymers reduce leaching of Cs compared to K-based geopolymers and the results are in agreement with the hard and soft acids and bases (HSAB) theory. Cs ions are weak Lewis acids and aluminates are a weak Lewis base. During the formation of the geopolymer matrix Cs ions are preferentially bound to aluminate phases and replace Na in the geopolymer structure. Sr uptake by Na-geopolymers is limited to 0.4 mol Sr per mole of Al and any additional Sr is immobilised by the high pH which causes precipitation of Sr as low solubility hydroxide and carbonate phases. There was no evidence of any other phases being formed when Sr or Cs are added to metakaolin geopolymers.

  5. The selective separation of Cs and Sr ion on the inorganic ion-exchanger zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hun Hwee; Min, Byeog Heon [Hoseo University, Taegu (Korea)

    1998-04-01

    This study shows the selective separation of Cs and Sr ion on the inorganic ion-exchanger zeolites such as clinoptilolite, Y-type CBV760, CBV780 and A-type 3A. The selective separation of Cs and Sr on these zeolites was examined using batch and continuous column experiments. For the selective separation of Cs and Sr from a synthetic wastewater, adsorption rate of Cs increased in the order, clinoptilolite> 3A>> CBV760> CBV780, adsorption rate of Sr increased in the other, 3A>> clinoptilolite> CBV760> CBV780. For the clinoptilolite, the adsorption rate of Cs reached about 96 {approx} 98% within 3h. The adsorption rate of Sr on 3A reached about 99% within 3h. (author). 40 refs., 27 figs., 4 tabs.

  6. [90Sr and 137Cs in higher aquatic plants of the Chernobyl nuclear plant exlusion zone

    Science.gov (United States)

    Gudkov, D I; Derevets, V V; Kuz'menko, M I; Nazarov, A B

    2001-01-01

    The content of radionuclides 90Sr and 137Cs in higher aquatic plants of water objects within Chernobyl NPP exclusion zone has been analysed. Biodiversity of phytocenose was studied and species-indicators of radioactive contamination were revealed. The seasonal dynamics of radionuclide content in macrophytes was studied and the role of main aquatic plant clumps in processes of 137Cs and 90Sr distribution in abiotic component of biohydrocenose was demonstrated.

  7. {sup 137}Cs and {sup 9}Sr uptake by sunflower cultivated under hydroponic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Soudek, Petr [Department of Plant Tissue Cultures, Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, CZ-166 10 Prague 6 (Czech Republic); Valenova, Sarka [Department of Plant Tissue Cultures, Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, CZ-166 10 Prague 6 (Czech Republic); Vavrikova, Zuzana [Department of Plant Tissue Cultures, Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, CZ-166 10 Prague 6 (Czech Republic); Vanek, Tomas [Department of Plant Tissue Cultures, Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, CZ-166 10 Prague 6 (Czech Republic)]. E-mail: vanek@uochb.cas.cz

    2006-07-01

    The {sup 9}Sr and {sup 137}Cs uptake by the plant Helianthus annuus L. was studied during cultivation in a hydroponic medium. The accumulation of radioactivity in plants was measured after 2, 4, 8, 16 and 32 days of cultivation. About 12% of {sup 137}Cs and 20% of {sup 9}Sr accumulated during the experiments. We did not find any differences between the uptake of radioactive and stable caesium and strontium isotopes. Radioactivity distribution within the plant was determined by autoradiography. {sup 137}Cs was present mainly in nodal segments, leaf veins and young leaves. High activity of {sup 9}Sr was localized in leaf veins, stem, central root and stomata. The influence of stable elements or analogues on the transfer behaviour was investigated. The percentage of non-active caesium and strontium concentration in plants decreased with the increasing initial concentration of Cs or Sr in the medium. The percentage of {sup 9}Sr activity in plants decreased with increasing initial activity of the nuclide in the medium, but the activity of {sup 137}Cs in plants increased. The influence of K{sup +} and NH{sub 4} {sup +} on the uptake of {sup 137}Cs and the influence of Ca{sup 2+} on the uptake of {sup 9}Sr was tested. The highest accumulation of {sup 137}Cs (24-27% of the initial activity of {sup 137}Cs) was found in the presence of 10 mM potassium and 12 mM ammonium ions. Accumulation of about 22% of initial activity of {sup 9}Sr was determined in plants grown on the medium with 8 mM calcium ions.

  8. Evaluation of factors influencing accumulation of stable Sr and Cs in lake and coastal fish.

    Science.gov (United States)

    Konovalenko, L; Bradshaw, C; Andersson, E; Lindqvist, D; Kautsky, U

    2016-08-01

    As a result of nuclear accidents and weapons tests, the radionuclides Cs-137 and Sr-90 are common contaminants in aquatic ecosystems. Concentration ratios (CR) based on concentrations of stable Cs and Sr in biota and media are used for the estimation of transfer of their radioisotopes for radiation dose calculations in environmental and human safety assessments. Available element-specific CRs vary by over an order of magnitude for similar organisms, thus affecting the dose estimates proportionally. The variation could be reduced if they were based on a better understanding of the influence of the underlying data and how that affects accumulation and potential biomagnification of stable Cs and Sr in aquatic organisms. For fish, relationships have been identified between water concentrations of K and CR of Cs-137, and between water concentrations of Ca and CR of Sr-90. This has not been confirmed for stable Cs and Sr in European waters. In this study, we analysed an existing dataset for stable Cs and Sr, as well as K and Ca, in four Swedish lakes and three Baltic Sea coastal areas, in order to understand the behaviour of these elements and their radioisotopes in these ecosystems. We found significant seasonal variations in the water concentrations of Cs, Sr, K and Ca, and in electrical conductivity (EC), especially in the lakes. CR values based on measurements taken at single or few time points may, therefore, be inaccurate or introduce unnecessarily large variation into risk assessments. Instead, we recommend incorporating information about the underlying variation in water concentrations into the CR calculations, for example by using the variation of the mean. The inverse relationships between fish CR(Cs)-[K]water and fish CR(Sr)-[Ca]water, confirmed that stable Cs and Sr follow the same trends as their radioisotopes. Thus, they can be used as proxies when radioisotope data are lacking. EC was also strongly correlated with K and Ca concentrations in the water and

  9. Sorption Characteristics of 137Cs and 90Sr into Rembang and Sumedang Soils

    Directory of Open Access Journals (Sweden)

    Budi Setiawan

    2016-12-01

    Full Text Available In order to understand the sorption behavior of 137Cs and 90Sr into soil sample from Rembang and Subang, it is important to estimate the effect of contact time, ionic strength and concentration of metal ion in the solution. For this reason, the interaction of 137Cs and 90Sr with soil sample has been examined. The study performed at trace concentration (~10-8 M of CsCl and SrCl2, and batch method was used. NaCl has been selected as a representative of the ionic strength with 0.1; 0.5 and 1.0 M concentrations. Concentration of 10-8~10-4 M CsCl and SrCl2 were used for study the effect of Cs and Sr concentrations in solution. Apparent distribution coefficient was used to predict the sorption behavior. The sorption equilibrium of 137Cs and 90Sr into soil was attained after 5 days contacted with Kd value around 3300-4200 mL/g, where Kd was defined as the ratio of number of radionuclide activity absorbed in solid phase per-unit mass to the number of radionuclide activity remains is solution per-unit volume. Presence of NaCl as background salt in the solution affected Kd values due to competition among metal ions into soil samples. Increase of Cs or Sr concentration in solution made Kd value decreased drastically. This information is expected could provide an important input for the planning and design of radioactive waste disposal system in Java Island in the future.

  10. Distributions of {sup 137}Cs and {sup 90}Sr in the soil of Uljin, South Korea

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ji Yeon; Kim, Wan; Maeng, Seong Jin; Lee, Sang Hoon [Kyungpook National University, Daegu (Korea, Republic of)

    2016-05-15

    For the purpose of baseline data collection and enhancement of environmental monitoring the distribution studies of {sup 137}Cs and {sup 90}Sr in the soil of Uljin province was performed and the relation between surface soil activities and soil properties (pH, TOC and median of the surface soil) was analyzed. For 14 spots within 10 km from the NPP surface soil samples were collected and soils for depth profile were sampled for 3 spots in April 2011. Using γ-ray spectrometry with HPGe detector, the concentrations of {sup 137}Cs were determined and the concentrations of {sup 90}Sr were measured by counting β-activity of {sup 90}Y (in equilibrium with {sup 90}Sr) in a gas flow proportional counter. The concentration ranges of {sup 137}Cs and {sup 90}Sr were <0.479-39.6 Bq (kg-dry)-1 (avg. 7.51 Bq·(kg-dry)-1) and 0.209-1.85 Bq·(kg-dry)-1 (avg. 0.74 Bq·(kg-dry)-1) which were similar to the reported values from other regions in Korea. The activity ratio of {sup 137}Cs to {sup 90}Sr in surface soils was around 9.67, which is much bigger than the initial value of 1.75 for worldwide fallouts because of faster downward movement of {sup 90}Sr after fall-out than that of {sup 137}Cs. For depth profile studies soils were collected down to 40 cm depth for the locations of Deokgu, Hujeong and Maehwa. The {sup 137}Cs concentration distribution of the first two showed maximum values at top soils and decreased rapidly in exponential manner, while {sup 90}Sr showed two local maximum values for soils near top and about 30 cm depth. Through linear fittings between the {sup 137}Cs and {sup 90}Sr concentrations of surface soil and pH, TOC and median of the surface soil, the only probable relationship obtained was between {sup 137}Cs and TOC (determination coefficient R2=0.6). The concentration ranges of {sup 137}Cs and {sup 90}Sr in Uljin were similar to the reported values from other regions in Korea. The only probable relationship obtained between activities and soil properties

  11. Activity concentrations of Rn-222, Ra-226, Ra-228, U-238 and Cs-137 in water samples of Styria/Austria; Aktivitaetskonzentrationen von Rn-222, Ra-226, Ra-228, U-238 und Cs-137 in Wasserproben aus der Steiermark/Oesterreich

    Energy Technology Data Exchange (ETDEWEB)

    Pichl, E. [Verein zur Foerderung der Strahlenforschung Oesterreich, Graz (Austria). Strahlenmesstechnik Graz; Rauch, P. [Land Steiermark (Austria). Abt. 15 - Energie, Wohnbau, Technik

    2015-07-01

    Activity concentrations of radon (Rn-222), radium (Ra-226, Ra-228), uranium (U-238), and radiocesium (Cs-137), were determined in 50 water samples from different geogenic regions of Styria/Austria. Samples were collected in the years 2010, 2011 and 2012, by experts of the Styrian government. For measuring activities of U-238 we used a low energy-semiconductor detector, and a high purity-semiconductor detector to analyze the activities of all the other radionuclides. More than 90% of the activity concentrations of Rn-222 in all water samples were lower than 50 Bq/l. All activity concentrations observed for radium and uranium were lower than the detection limits of the corresponding radionuclides (Ra-226: 0,02 Bq/l, Ra-228: 0,03 Bq/l, U-238: 0,06 Bq/l). None of the water samples were contaminated by Cs-137.

  12. The radial distribution of [sup 90]Sr and [sup 137]Cs in trees

    Energy Technology Data Exchange (ETDEWEB)

    Nomoshima, N. (Kyushu Univ., Fukuoka (Japan). Faculty of Science); Bondietti, E.A. (Oak Ridge National Lab., TN (United States). Environmental Sciences Div.)

    1994-01-01

    The distributions of [sup 90]Sr and [sup 137]Cs in tree trunks were measured for eight species. The concentration of [sup 137]Cs was relatively uniform in the wood xylem and did not show any correlation with the temporal record of cumulative deposition of fallout in the northern hemisphere, indicating that [sup 137]Cs was mobile in the wood xylem. The distributions of [sup 90]Sr were classified into three groups. All of the gymnosperms - red spruce, eastern hemlock and white pine - showed a maximum [sup 90]Sr specific activity in rings formed in the 1960s and the overall distribution was closely associated with the temporal record of the cumulative deposition of fallout. Three of five angiosperms -hickory, elm and American beech - showed similar distributions to the gymnosperms except that the maximum [sup 90]Sr specific activity corresponded to the 1970s. The other two angiosperms - yellow poplar and sugar maple - did not show any correlation with the cumulative fallout deposition. The radial distribution of [sup 90]Sr in gymnosperms was simulated considering a steady-state cycling of [sup 90]Sr in the forest ecosystem. The model suggested that a few per cent of stable Sr are replaced annually in the nutrient pool of gymnosperms. (Author).

  13. Hydrothermal preparation of tobermorite from blast furnace slag for Cs+ and Sr2+ sorption.

    Science.gov (United States)

    Tsutsumi, Takuma; Nishimoto, Shunsuke; Kameshima, Yoshikazu; Miyake, Michihiro

    2014-02-15

    Al-substituted 11Å-tobermorite was formed by alkaline hydrothermal treatment of blast furnace slag with sodium silicate added at 180°C for 2-48 h. Effects of the hydrothermal treatment time were characterized by XRD, SEM, and isothermal adsorption of N2. Sorption characteristics of the obtained samples were examined for Cs(+) and Sr(2+). The sample obtained by hydrothermal treatment for 48 h (HT-48 h) consisted of calcium silicate hydrate (C-S-H), and Al-substituted 11Å-tobermorite. The HT-48 h showed the highest performance for Cs(+) and Sr(2+) selectivity in the presence of Na(+). The interlayer Na(+) of Al-substituted 11Å-tobermorite and surface Ca(2+) played an important role in selective Cs(+) and Sr(2+).

  14. A Discussion of Reversible and Irreversible Sorption for Sr, Cs, Np, and Pu

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, Susan [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Tinnacher, Ruth [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kersting, Annie [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zavarin, Mavrik [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2010-04-30

    Here we discuss the possibility that fission product and actinide sorption is reversible when thermodynamic and kinetic factors are accounted for in predictive models. We do this by reviewing the sorption behavior of Sr, Cs, Np, and Pu, and by reviewing our ability to model their sorption behavior.

  15. Development of Composite Adsorbents for LLW Treatment and Their Adsorption Properties for Cs and Sr - 13127

    Energy Technology Data Exchange (ETDEWEB)

    Susa, Shunsuke; Mimura, Hitoshi [Dept. of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Aramaki-Aza-Aoba 6-6-01-2, Sendai, 980-8579 (Japan); Ito, Yoshiyuki; Saito, Yasuo [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, 2-4 Shirakata Shirone, Naka-gun, Ibaraki, 319-1195 (Japan)

    2013-07-01

    In this study, the composite adsorbents (KCoFC-NM (NM: natural mordenite), KCoFC-SG (SG: porous silica gel), AMP-SG and so on) were prepared by impregnation-precipitation methods. As for the distribution properties, the largest K{sub d,Cs} value of 3.8 x 10{sup 4} cm{sup 3}/g was obtained for KCoFC-SG (Davi.) composite. KCoFC-SG (NH, MB5D) and T-KCFC also had relatively large K{sub d,Cs} values above 1.0 x 10{sup 4} cm{sup 3}/g. The uptake rate of Cs{sup +} ions was examined by batch method. KCoFC-SG (NH, MB5D) and AMP-SG (Davi.) had relatively large uptake rate of Cs{sup +}, and the uptake attained equilibrium within 1 h. The maximum uptake capacity of Cs{sup +} ions was estimated to be above 0.5 mmol/g for KCoFC-NM and KCoFC-CP composites. KCoFC-X composite had a relatively large uptake capacity of Cs{sup +} ions (0.23 mmol/g > 0.17 mmol/g (T-KCFC)) and this composite also had a selectivity towards Sr{sup 2+} ions; KCoFC-X is effective adsorbent for both Cs{sup +} and Sr{sup 2+} ions. The largest value of K{sub d,Sr} was estimated to be 218 cm{sup 3}/g for titanic acid-PAN. Titanic acid-PAN had the largest uptake rate of Sr{sup 2+} ions, and the uptake attained equilibrium within 8 h. Adsorbability of other nuclides was further examined by batch method. All adsorbents had adsorbability for Rb{sup +} and RuNO{sup 3+} ions. KCoFC-SG (NH), KCoFC-CP and T-KCFC had higher selectivity towards Cs{sup +} than other adsorbents; these adsorbents had adsorbability to Cs{sup +} ions even in the presence of Ba{sup 2+}, Ca{sup 2+} and Mg{sup 2+} ions. The separation factor of K{sub d,Sr}/K{sub d,Ba} for titanic acid-PAN was about 1, indicating that the K{sub d,Sr} for titanic acid-PAN tends to decrease with Ba{sup 2+} concentration. As for the breakthrough properties, the largest 5 % breakpoint and 5 % breakthrough capacity of Cs{sup +} ions were estimated to be 47.1 cm{sup 3} and 0.07 mmol/g for the column of KCoFC-SG (NH), respectively. The order of 5 % breakthrough capacity

  16. Mass spectrometry for the determination of fission products 135Cs, 137Cs and 90Sr: A review of methodology and applications

    Science.gov (United States)

    Bu, Wenting; Zheng, Jian; Liu, Xuemei; Long, Kaiming; Hu, Sheng; Uchida, Shigeo

    2016-05-01

    The radioactive fission products 135Cs, 137Cs and 90Sr have been released into the environment by human activities such as nuclear weapon tests, nuclear fuel reprocessing and nuclear power plant accidents. Monitoring of these radionuclides is important for dose assessment. Moreover, the 135Cs/137Cs isotopic ratio can be used as an important long-term fingerprint for radioactive source identification as it varies with weapon, reactor and fuel types. In recent years, mass spectrometry has become a powerful method for the determination of 135Cs, 137Cs and 90Sr in environmental samples. Mass spectrometry is characterized by the high sensitivity and low detection limit and the relatively shorter sample preparation and analysis times compared with radiometric methods. However, the mass spectrometric determination of radiocesium and 90Sr is affected by the peak tailings of the stable nuclides 133Cs and 88Sr, respectively, and the related isobaric and polyatomic interferences. Chemical separation and optimization of the mass spectrometry instrumental setup are strongly needed prior to the mass spectrometry detection. In this paper, we have reviewed the published works about the determination of 135Cs, 137Cs and 90Sr by mass spectrometry. The mass spectrometric techniques we cover are resonance ionization mass spectrometry (RIMS), thermal ionization mass spectrometry (TIMS), accelerator mass spectrometry (AMS) and inductively coupled plasma mass spectrometry (ICP-MS). For each technique, the principles or strategies used for the analysis of these radionuclides are discussed; these included the abundance sensitivity, ways to suppress the interference signals, and the instrumental setup. In particular, the chemical procedures for eliminating the interferences are also summarized. To date, triple quadrupole ICP-MS (ICP-QQQ) showed great ability for the analysis of these radionuclides and the detection limits were as low as 0.01 pg/mL levels. Finally, some investigations on the

  17. Cumulative deposition of fallout-derived {sup 137}Cs, {sup 90}Sr, {sup 239,240}Pu in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Myung Ho; Choi, Gun Sik; Hong, Kwang Hee; Cho, Yung Hyun; Lee, Chang Woo [KAERI, Taejon (Korea, Republic of)

    1999-07-01

    The data of cumulative depositions of {sup 239,240}Pu, {sup 90}Sr and {sup 137}Cs in the terrestrial soil and sea sediment of Korea are presented in this paper. The highest inventory of {sup 239,240}Pu, {sup 90}Sr and {sup 137}Cs was found in the volcanic ash soil and the lowest inventory was found in the arable soil. Organic substances and rainfall have a significant influence on deposition of {sup 239,240}Pu, {sup 90}Sr and {sup 137}Cs in the terrestrial soil. From depth profiles, most of {sup 239,240}Pu, {sup 90}Sr and {sup 137}Cs is accumulated in the layer of upper 10 cm of soil and the concentrations of {sup 239,240}Pu, {sup 90}Sr and {sup 137}Cs decreased with increasing depth. The maximum concentrations of {sup 239,240}Pu and {sup 137}Cs in the sediment match the input records of global fallout. The activity ratios of {sup 239,240}Pu / {sup 137}Cs and {sup 90}Sr / {sup 137}Cs in the terrestrial soil are close to the estimated value attributed to the fallout. The activity ratios of {sup 239,240}Pu / {sup 137}Cs in the sediment were higher than those in terrestrial soils. (author). 18 refs., 1 tab., 5 figs.

  18. Experimental studies of Cs, Sr, Ni, and Eu sorption on Na-illite and the modelling of Cs sorption

    Energy Technology Data Exchange (ETDEWEB)

    Poinssot, C.; Baeyens, B.; Bradbury, M.H.

    1999-08-01

    A natural illite (illite du Puy) was purified and converted to the homo-ionic Na-form. The conditioned Na-illite was characterised in terms of its mineralogy, chemical inventory and physico-chemical properties. The structural formula was determined from energy dispersive spectroscopic analyses (SEM/TEM-EDS) and bulk chemistry measurements. A cation exchange capacity of 127 meq kg{sup -1} was determined by the {sup 22}Na isotope dilution method at neutral pH. The Na-CEC was also measured as a function of pH. The stability of Na-illite as a function of pH in the range between 3 and 6 was investigated. At low pH values partial dissolution of the illite occurs releasing the structural elements Al, Si, Mg, and K into solution. The presence of Ca and Sr in solution was interpreted as being due to desorption from cation exchange sites. All of these elements are also present at neutral pH but at considerably lower levels. Such effects cannot be avoided and must be considered in the interpretation of the sorption measurements. The main focus of the experimental work presented here is on the sorption behaviour of Cs, Sr, Ni and Eu on conditioned Na-illite as a function of NaClO{sub 4} background electrolyte concentration (0.1 and 0.01 M), nuclide concentration and pH in the range between 3 and 11. Sorption edge data (R{sub d} versus pH) and sorption isotherms (quantity of nuclide sorbed versus equilibrium nuclide concentration) are presented for these four elements. Prior to beginning these experiments, sorption kinetics were measured. The broad based pool of sorption measurements generated from this work will provide the source data sets for subsequent modelling. So far only the Cs sorption measurements have been modelled. A two site cation exchange model was developed to describe the sorption of Cs over the whole range of experimental conditions. The two site types were termed 'frayed edge sites' (FES, high affinity/low capacity) and 'type II sites

  19. {mu} {sup +}SR study of zero-field magnetic ordering in CsC{sub 60}

    Energy Technology Data Exchange (ETDEWEB)

    Cristofolini, L.; Lappas, A.; Vavekis, K.; Prassides, K.; DeRenzi, R.; Ricco, M.; Schenck, A.; Amato, A.; Gygax, F.N.; Kosaka, M.; Tanigaki, K. [Sch. of Chem. and Molecular Sci., Sussex Univ., Brighton (United Kingdom)

    1995-10-23

    We have measured the zero-field muon spin relaxation (ZF {mu} {sup +}SR) spectra of the quasi-one-dimensional fulleride conductor CsC{sub 60}. Static magnetic order of a random nature develops gradually below about 30 K. The local field distribution at the muon site has a Gaussian shape with a width of 48.3(7) G at 2.8 K. Muon spin rotation (TF {mu} {sup +}SR) measurements at an applied transverse field of 6 kG also show the onset of magnetic order in the same temperature range. (authors). Letter-to-the-editor.

  20. Patterns of Cs-137 and Sr-90 distribution in conjugated landscape systems

    Science.gov (United States)

    Korobova, E.

    2012-04-01

    The main goal of the study was to reveal spatial patterns of 137Cs and 90Sr distribution in soils and plants of conjugated landscapes and to use 137Cs as a tracer for natural migration and accumulation processes in the environment. The studies were based on presumptions that: 1) the environment consisted of interrelated bio- and geochemical fields of hierarchical structure depending on the level and age of factors responsible for spatial distribution of chemical elements; 2)distribution of technogenic radionuclides in natural landscapes depended upon the location and type of the initial source and radionuclide involvement in natural pathways controlled by the state and mobility of the typomorphic elements and water migration. Case studies were undertaken in areas subjected to contamination after the Chernobyl accident and in the estuary zones of the Yenisey and Pechora rivers. First observations in the Chernobyl remote zone in 1987-1989 demonstrated relation between the dose rate, 137Cs, 134Cs, 144Ce, 106Ru, 125Sb in soil cover and the location of the measured plot in landscape toposequence. Later study of 137Cs and 90Sr concentration and speciation confirmed different patterns of their distribution dependent upon the radioisotope, soil features and vegetation cover corresponding to the local landscape and landuse structure. Certain patterns in distribution and migration of 137Cs and 90Sr in soils and local food chain were followed in private farms situated in different landscape position [1]. Detailed study of 137Cs activity in forested site with a pronounced relief 20 and 25 years after the Chernobyl accident showed its stable polycentric structure in soils, mosses and litter which was sensitive to meso- and micro-relief features [2]. Radionuclide contamination of the lower Yenisey and Pechora studied along meridian landscape transects proved both areas be subjected to global 137Cs pollution while the Yenisey floodplain received additional regional contamination

  1. Activity concentrations of {sup 137}Cs and {sup 90}Sr in seawaters of East Sea, Korea

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hae Young [Radiation Science Research Institute, Kyungpook National University, Daegu (Korea, Republic of); Maeng, Seong Jin; Lee, Sang Hoon [School of Architectural, Civil, Environmental and Energy Engineering, Kyungpook National University, Daegu (Korea, Republic of); Kim, Yong Hwan [Gyeongbuk Institute for Marine Bio-Industry, Daegu (Korea, Republic of)

    2016-09-15

    This study was a long-term evaluation of {sup 137}Cs and {sup 90}Sr activity concentrations in seawater samples from the East Sea, Korea, in order to establish current activity levels. Results and long-term monitoring trends will be useful in the future monitoring of environmental radioactivity. Surface seawater samples were collected quarterly from Guryongpo and Jangho in the East Coast between 1998 and 2010 and the quarterly deep seawater samples were collected from three sites in the sea adjacent to Ulleung-do between 2012 and 2015. The activity concentrations of {sup 13}7Cs were measured using a gamma-spectrometer. The activity concentrations of {sup 90}Sr and {sup 90}Y in a radioactive equilibrium state were measured using a gas flow proportional counter. We found the annual average activity concentrations of {sup 137}Cs in the surface seawater was 1.66-2.89 mBq·kg{sup -1} in Guryongpo and 1.68-2.43 mBq·kg{sup -1} in Jangho. The annual average activity concentrations of {sup 90}Sr in the surface seawater was 0.83-1.98 mBq·kg{sup -1} in Guryongpo and 0.82-1.57 mBq·kg{sup -1} in Jangho. The annual average activity concentrations of {sup 137}Cs in the deep seawater sites were 1.51-1.73 mBq·kg{sup -1}, 1.19-1.60 mBq·kg{sup -1} and 0.87-1.15 mBq·kg{sup -1} in TH, JD, and HP. The annual average activity concentrations of {sup 90}Sr in the same deep seawater sites were 1.00-1.94 mBq·kg{sup -1}, 0.82-1.26 mBq·kg{sup -1}, and 0.79-1.32 mBq·kg{sup -1}. The effective half-life was calculated by analyzing change over time in the activity concentration in the surface seawater. The effective half-life of {sup 137}Cs was 15.3±0.1 years in Guryongpo and 102±3 years in Jangho. The effective half-life of {sup 90}Sr was 28.3±4.3 years in Guryongpo and 16.6±0.1 years in Jangho. The ratio of the average activity concentration ({sup 137}Cs/{sup 90}Sr) was 1.72 in the surface seawater, which is similar to the reported ratio of the global radioactive fallout. The ratio

  2. Reassessment of (90)Sr, (137)Cs, and (134)Cs in the Coast off Japan Derived from the Fukushima Dai-ichi Nuclear Accident.

    Science.gov (United States)

    Castrillejo, Maxi; Casacuberta, Núria; Breier, Crystaline F; Pike, Steven M; Masqué, Pere; Buesseler, Ken O

    2016-01-05

    The years following the Fukushima Dai-ichi nuclear power plant (FDNPP) accident, the distribution of (90)Sr in seawater in the coast off Japan has received limited attention. However, (90)Sr is a major contaminant in waters accumulated within the nuclear facility and in the storage tanks. Seawater samples collected off the FDNPP in September 2013 showed radioactive levels significantly higher than pre-Fukushima levels within 6 km off the FDNPP. These samples, with up to 8.9 ± 0.4 Bq·m(-3) for (90)Sr, 124 ± 3 Bq·m(-3) for (137)Cs, and 54 ± 1 Bq·m(-3) for (134)Cs, appear to be influenced by ongoing releases from the FDNPP, with a characteristic (137)Cs/(90)Sr activity ratio of 3.5 ± 0.2. Beach surface water and groundwater collected in Sendai Bay had (137)Cs concentrations of up to 43 ± 1 Bq·m(-3), while (90)Sr was close to pre-Fukushima levels (1-2 Bq·m(-3)). These samples appear to be influenced by freshwater inputs carrying a (137)Cs/(90)Sr activity ratio closer to that of the FDNPP fallout deposited on land in the spring of 2011. Ongoing inputs of (90)Sr from FDNPP releases would be on the order of 2.3-8.5 GBq·d(-1) in September 2013, likely exceeding river inputs by 2-3 orders of magnitude. These results strongly suggest that a continuous surveillance of artificial radionuclides in the Pacific Ocean is still required.

  3. Separation of CsCl and SrCl2 from a ternary CsCl-SrCl2-LiCl via a zone refining process for waste salt minimization of pyroprocessing

    Science.gov (United States)

    Shim, Moonsoo; Choi, Ho Gil; Yi, Kyung Woo; Hwang, Il Soon; Lee, Jong Hyeon

    2016-11-01

    The purification of LiCl salt mixture has traditionally been carried out by a melt crystallization process. To improve the throughput of zone refining, three heaters were installed in the zone refiner. The zone refining method was used to grow pure LiCl salt ingots from LiCl-CsCl-SrCl2 salt mixture. The main investigated parameters were the heater speed and the number of passes. A change in the LiCl crystal grain size was observed according to the horizontal direction. From each zone refined salt ingot, samples were collected horizontally. To analyze the concentrations of Sr and Cs, an inductively coupled plasma optical emission spectrometer and inductively coupled plasma mass spectrometer were used, respectively. The experimental results show that Sr and Cs concentrations at the initial region of the ingot were low and reached their peak at the final freezing region of the salt ingot. Concentration results of zone refined salt were compared with theoretical results yielded by the proposed model to validate its predictions. The keff of Sr and Cs were 0.13 and 0.11, respectively. The decontamination factors of Sr and Cs were 450 and 1650, respectively.

  4. The uptake of Cs and Sr from soil to radish (Raphanus sativus L.)- potential for phytoextraction and remediation of contaminated soils.

    Science.gov (United States)

    Wang, Dan; Wen, Fangping; Xu, Changhe; Tang, Yunlai; Luo, Xuegang

    2012-08-01

    The (133)Cs and (88)Sr uptake by plant Raphanus sativus L. was studied during cultivation in outdoor potted-soil. The distribution, accumulation of (133)Cs, (88)Sr and the antioxidant responses in plants were measured after 30 and 60 days of cultivation. The results showed that the uptake capacity of radish for (88)Sr was far higher than that for (133)Cs when the concentration of (88)Sr was as the same as that of (133)Cs in the soil (The concentration of (88)Sr or (133)Cs in the soil was from 2.5 mg kg(-1) to 40 mg kg(-1)). The highest (88)Sr accumulation was 239.18 μg g(-1) dw, otherwise, the highest (133)Cs accumulation was 151.74 μg g(-1) dw (The concentration of (88)Sr in the soil was 40 mg kg(-1)), and the lowest (88)Sr accumulation was 131.03 μg g(-1) dw, otherwise, the lowest (133)Cs accumulation was 12.85 μg g(-1) dw (The concentration of (88)Sr in the soil is 5 mg kg(-1)). The (88)Sr and (133)Cs TF values were 1.16-1.72 and 0.24-0.60, respectively. There was little influence of high concentration of (88)Sr on the total biomass of plants, so the radish is one of the ideal phytoremediation plant for Sr polluted soils. The important physiological reasons that radish had good tolerance to (88)Sr stress were that the MDA content was higher under the (88)Sr stress than that under the (133)Cs stress, and the activities of POD and CAT were lower under the (88)Sr stress than that under (133)Cs stress.

  5. Local-scale modelling of the releases of 137-Cs and 90-Sr from Fukushima NPP into the Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Raul, Perianez [Universidad de Sevilla, Spain (Korea, Republic of)

    2013-10-15

    The dispersion of 137-Cs and 90-Sr released from Fukushima nuclear power plant to the sea after the March 11th 2011 tsunami has been studied using a numerical model. The 3D dispersion model consists of an advection/diffusion equation with terms describing uptake/release reactions between water and seabed sediments. The dispersion model has been fed with daily currents provided by JCOPE2 ocean model. Seabed sediment 137-Cs computed patterns have been compared with observations. The impact of tides and of atmospheric deposition on sediment contamination has been evaluated as well. First simulations carried out for Sr-90 are described. An evaluation of the amount of this radionuclide released to the sea has been made using a numerical model for the first time. Calculated vertical profiles of this radionuclide have been compared with measured ones. Finally, the variability in 90-Sr/137-Cs activity ratios has been analysed with the model.

  6. Preparation and photocatalytic performance of Cs+/Sr2+-doped nano-sized TiO2

    Institute of Scientific and Technical Information of China (English)

    罗洁; 李德良; 金明子

    2009-01-01

    The un-doped TiO2 and Cs+/Sr2+-doped TiO2 nanometer particles were prepared by sol-gel method using tetrabutyl titanate (Ti(OC4H9)4) as TiO2 precursor,and characterized with X-ray diffraction (XRD) and UV-Vis absorption spectra (UV-Vis). The photocatalytic activities of these samples were investigated by the photocatalytic degradation of methyl orange in aqueous suspension under 300 W medium pressure mercury lamp irradiation. The results show that the growth of crystallite size can be controlled effectively for the Cs+/Sr2+-doped TiO2,and crystal phase transformation of nano-sized TiO2 is retarded from anatase structure to rutile structure while using the proper doping concentration of Cs+/Sr2+. It is pure anatase of high photocatalytic activity for Cs+/Sr2+-doped nano-sized TiO2 prepared at 600 ℃ for 2 h. The average crystal sizes of un-doped TiO2,0.1% Cs+-doped TiO2 and 0.3% Sr2+-doped TiO2 are 21.3,13.1 and 10.8 nm,respectively. Moreover,the doping TiO2 can extend the light response to the visible region at 400-600 nm. By measuring their photocatalytic degradation rate of methyl orange solution,the results indicate that Cs+/Sr2+ -doped TiO2 samples are found to improve photocatalytic degradation activity of TiO2 markedly,and the optimal doping concentration is determined to be 0.1% and 0.3% for Cs+ and Sr2+,respectively. Photocatalytic degradation rate of Cs+/Sr2+-doped nano-sized TiO2 can be 15%-25% higher than that of un-doped TiO2 under the same condition.

  7. On-line ion chemistry for the AMS analysis of {sup 90}Sr and {sup 135,137}Cs

    Energy Technology Data Exchange (ETDEWEB)

    Eliades, J. [IsoTrace Laboratory, University of Toronto, 60 St. George St., Toronto, ON, M5S 1A7 (Canada); Zhao, X.-L. [Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, ON, K1N 6N5 (Canada); Litherland, A.E. [IsoTrace Laboratory, University of Toronto, 60 St. George St., Toronto, ON, M5S 1A7 (Canada); Kieser, W.E., E-mail: liam.kieser@utoronto.ca [Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, ON, K1N 6N5 (Canada)

    2013-01-15

    The analysis of {sup 90}Sr by AMS has so far required the use of very large tandem accelerators in order to separate the isobar {sup 90}Zr by the rate-of-energy-loss method. The analysis of {sup 135,137}Cs by AMS has never been attempted as the separation of the isobars {sup 135,137}Ba by the traditional method requires even higher energies, so that this approach would become prohibitively expensive for routine analysis. Following the successful demonstration of Cl{sup -}-S{sup -} separation by the Isobar Separator, the same apparatus was used to test the separation of other pairs of isobars. Surprisingly effective results were obtained with NO{sub 2} gas in the cases of SrF{sub 3}{sup -}-ZrF{sub 3}{sup -} and CsF{sub 2}{sup -}-BaF{sub 2}{sup -} separations. Reduction factors of {approx}4 Multiplication-Sign 10{sup -6} for ZrF{sub 3}{sup -}/SrF{sub 3}{sup -} and {approx}2 Multiplication-Sign 10{sup -5} for BaF{sub 2}{sup -}/CsF{sub 2}{sup -} were measured. SrF{sub 3}{sup -} and CsF{sub 2}{sup -} are both super-halogen anions and are preferentially produced in the ion source rather than ZrF{sub 3}{sup -} and BaF{sub 2}{sup -} when using the PbF{sub 2} matrix-assisted method. Reduction factors for ion source production with such targets of {approx}3 Multiplication-Sign 10{sup -5} for ZrF{sub 3}{sup -}-SrF{sub 3}{sup -} and {approx}5 Multiplication-Sign 10{sup -4} for BaF{sub 2}{sup -}-CsF{sub 2}{sup -} were found. The combined methods would suggest a theoretical detection sensitivity for {sup 90}Sr/Sr {approx}6 Multiplication-Sign 10{sup -16}, {sup 135}Cs/Cs {approx}7 Multiplication-Sign 10{sup -15} and {sup 137}Cs/Cs {approx}1 Multiplication-Sign 10{sup -14}, assuming 10 ppm Zr and Ba contamination in the AMS targets. In addition to the earlier Cl{sup -}-S{sup -} separation work, these measurements further illustrate the potential of on-line ion chemical methods for broadening the analytical scope of small AMS systems.

  8. [Radionuclides 90Sr and 137Cs in the benthos near the nuclear submarine "Komsomolets"].

    Science.gov (United States)

    Kuznetsov, A P; Shmelev, I P; Demidov, A M; Efimov, B V; Shubko, V M

    1999-01-01

    We have analyzed the content of radionuclides 90Sr and 137Cs in the benthofauna and deposits near the nuclear submarine "Komsomolets." Analysis was performed on the basis of the materials of the 31st (1993) and 36th (1995) voyages of R/V "Akademik Mstislav Keldysh" in correspondence with the system of monitoring the state of the abiotic and biotic situation near the nuclear submarine "Komsomolets" (Norwegian Sea). Whereas during the 33rd voyage of this vessel (1994) the content of these elements in the benthic animals at stations located close to the submarine somewhat exceeded the background level of radioactivity (Kuznetsov et al., 1996), no such excess was found during the 31st and 36th voyages. Meanwhile, radioactive cobalt (60Co) was found in representatives of three groups of animals during the 31st voyage at two stations located near the submarine.

  9. Fertilization influence on the {sup 137}Cs and {sup 90}Sr uptake by crops

    Energy Technology Data Exchange (ETDEWEB)

    Bogdevitch, I.; Tarasuk, S.; Shmigelskaya, I.; Putyatin, Y. [Belarussian Research Institute for Soil Science and Agrochemistry (BRISSA), Kazintsa 62, Minsk 220108 (Belarus)

    2003-07-01

    Reducing the risk of people internal irradiation based on decreasing of radionuclide concentration in consumed food stuff is a main objective for justified application of the countermeasures on contaminated agricultural land at the last period after Chernobyl radioactive fallout. Liming, fertilizers and manure application are the most widespread, applicable and effective countermeasures to restrict the soil-to-plant radionuclide transfer. Efficiency of the fertilization depends on radionuclide deposition, texture and chemical properties of the soils, biological characteristics of plants and type of the fertilizers. The selection of the types of agro-chemical treatments should be considered with combined economical and radiological justification. Countermeasures treatments have to lead to the profitable or self-sufficient production of extra yield with low radionuclide contamination. As objective of this work, mentioned is the assessment of the different types of agro-chemical countermeasures on agricultural land contaminated by {sup 137}Cs and {sup 90}Sr based on radiological economical justification. The efficiency of K fertilizer on different K supply soils, the efficiency of balanced fertilization at the different rates of manure utilization and the efficiency of liming and K fertilizer rates are presented. In conclusion, the soil fertility improvement based on balanced fertilization and liming to achieve the optimal agro-chemical properties allow significantly (up to 2-4 times) reduce the concentration of {sup 137}Cs and {sup 90}Sr in crop production with the simultaneous yield increase. The agro-chemical countermeasures targeted for balanced plant nutrition should have priority, on the assumption of providing the profitable or self-sufficient production of extra yield to pay for expenses. The profitability of agricultural production is a main criterion for justification of countermeasure application in long-term period after Chernobyl accident.

  10. Investigation of (235)U, (226)Ra, (232)Th, (40)K, (137)Cs, and heavy metal concentrations in Anzali international wetland using high-resolution gamma-ray spectrometry and atomic absorption spectroscopy.

    Science.gov (United States)

    Zare, Mohammad Reza; Kamali, Mahdi; Fallahi Kapourchali, Maryam; Bagheri, Hashem; Khoram Bagheri, Mahdi; Abedini, Ali; Pakzad, Hamid Reza

    2016-02-01

    Measurements of natural radioactivity levels and heavy metals in sediment and soil samples of the Anzali international wetland were carried out by two HPGe-gamma ray spectrometry and atomic absorption spectroscopy techniques. The concentrations of (235)U, (226)Ra, (232)Th, (40)K, and (137)Cs in sediment samples ranged between 1.05 ± 0.51-5.81 ± 0.61, 18.06 ± 0.63-33.36 ± .0.34, 17.57 ± 0.38-45.84 ± 6.23, 371.88 ± 6.36-652.28 ± 11.60, and 0.43 ± 0.06-63.35 ± 0.94 Bq/kg, while in the soil samples they vary between 2.36-5.97, 22.71-38.37, 29.27-42.89, 472.66-533, and 1.05-9.60 Bq/kg for (235)U, (226)Ra, (232)Th, (40)K, and (137)Cs, respectively. Present results are compared with the available literature data and also with the world average values. The radium equivalent activity was well below the defined limit of 370 Bq/kg. The external hazard indices were found to be less than 1, indicating a low dose. Heavy metal concentrations were found to decrease in order as Fe > Mn > Sr > Zn > Cu > Cr > Ni > Pb > Co > Cd. These measurements will serve as background reference levels for the Anzali wetland.

  11. Emergency Radiobioassay Method for Determination of ⁹⁰Sr and ²²⁶Ra in a Spot Urine Sample.

    Science.gov (United States)

    Sadi, Baki B; Fontaine, Allison; McAlister, Daniel; Li, Chunsheng

    2015-08-04

    A new radiobioassay method has been developed for simultaneous determination of (90)Sr and (226)Ra in a spot urine sample. The method is based on a matrix removal procedure to purify the target radionuclides from a urine sample followed by an automated high performance ion chromatographic (HPIC) separation of (90)Sr and (226)Ra and offline radiometric detection by liquid scintillation counting (LSC). A Sr-resin extraction chromatographic cartridge was used for matrix removal and purification of (90)Sr and (226)Ra from a urine sample prior to its introduction to the HPIC system. The HPIC separation was carried out through cation exchange chromatography using methanesulfonic acid (75 mM) as the mobile phase at 0.25 mL/min flow rate. The performance criteria of the method was evaluated against the American National Standard Institute ANSI/HPS N13.30-2011 standard for the root mean squared error (RMSE) of relative bias (Br) and relative precision (SB) at two different spiked activity levels. The RMSE of Br and SB for (90)Sr and (226)Ra were found to be satisfactory (≤0.25). The minimum detectable activity (MDA) of the method for (90)Sr and (226)Ra are 2 Bq/L and 0.2 Bq/L, respectively. The MDA values are at least 1/10th of the concentrations of (90)Sr (190 Bq/L) and (226)Ra (2 Bq/L) excreted in urine on the third day following an acute exposure (inhalation) that would lead to an effective dose of 0.1 Sv in the first year. The sample turnaround time is less than 8 h for simultaneous determination of (90)Sr and (226)Ra.

  12. Uptakes of Cs and Sr on San Joaquin soil measured following ASTM method C1733.

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, W.L.; Petri, E.T. (Chemical Sciences and Engineering Division)

    2012-04-04

    Series of tests were conducted following ASTM Standard Procedure C1733 to evaluate the repeatability of the test and the effects of several test parameters, including the solution-to-soil mass ratio, test duration, pH, and the concentrations of contaminants in the solution. This standard procedure is recommended for measuring the distribution coefficient (K{sub d}) of a contaminant in a specific soil/groundwater system. One objective of the current tests was to identify experimental conditions that can be used in future interlaboratory studies to determine the reproducibility of the test method. This includes the recommendation of a standard soil, the range of contaminant concentrations and solution matrix, and various test parameters. Quantifying the uncertainty in the distribution coefficient that can be attributed to the test procedure itself allows the differences in measured values to be associated with differences in the natural systems being studied. Tests were conducted to measure the uptake of Cs and Sr dissolved as CsCl and Sr(NO{sub 3}){sub 2} in a dilute NaHCO{sub 3}/SiO{sub 2} solution (representing contaminants in a silicate groundwater) by a NIST standard reference material of San Joaquin soil (SRM 2709a). Tests were run to measure the repeatability of the method and the sensitivity of the test response to the reaction time, the mass of soil used (at a constant soil-to-solution ratio), the solution pH, and the contaminant concentration. All tests were conducted in screw-top Teflon vessels at 30 C in an oven. All solutions were passed through a 0.45-{mu}m pore size cellulose acetate membrane filter and stabilized with nitric acid prior to analysis with inductively-coupled plasma mass spectrometry (ICP-MS). Scoping tests with soil in demineralized water resulted in a solution pH of about 8.0 and the release of small amounts of Sr from the soil. Solutions were made with targeted concentrations of 1 x 10{sup -6} m, 1 x 10{sup -5} m, 2.5 x 10{sup -5} m, 5

  13. Ageing impact on the transfer factor of (137)Cs and (90)Sr to lettuce and winter wheat.

    Science.gov (United States)

    Al Attar, Lina; Al-Oudat, Mohammad; Safia, Bassam; Abdul Ghani, Basem

    2016-11-01

    The study focuses on long-term (extending from 1 to 10 years) lysimeter experiments of the transfer factor of (137)Cs and (90)Sr to lettuce and winter wheat crops. Transfer factors (Fvs) were the ratio of the activity concentrations of the radionuclides in crops to those in soil, both as dry weight (Bq kg(-1)). Fvs of (137)Cs to lettuce decreased significantly with ageing; geometric means for the 1(st), 2(nd) and 10(th) year contaminated soil were 0.114, 0.030 and 0.013, respectively. However, a significant decline of Fvs for (137)Cs was only seen between the 1(st) and 2(nd) year for both wheat compartments (straw and grains) which disappeared thereafter. The dynamic of (137)Cs Fvs may be explained according to the distribution coefficient experiment (Kd) which had a value of 3600 L kg(-1) showing a high affinity of the clay minerals for caesium. Desorption data revealed that Cs fixation enhanced with ageing. The mechanism involved may be an initial sorption of caesium species to the surface soil particles followed by progressive irreversible fixation to the interlayer of the porous clay minerals. Fvs of (90)Sr were high and showed trivial variation for both crops for the time course studied. Sorption of Sr(2+) species to the clay mineral may be the governing process, which was supported by high desorption percentage (ranged 77%) with low Kd, i.e. 10 L kg(-1). In general, higher Fvs of (137)Cs and (90)Sr for lettuce was observed in comparison to winter wheat. The diversity of plant species and root systems would play essential roles for such behaviours. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Separation and immobilization of Sr and Cs contained in acidic media by using inorganic ion-exchangers. Literature survey

    Energy Technology Data Exchange (ETDEWEB)

    Yamagishi, Isao [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-07-01

    The present study deals with the survey of inorganic ion-exchangers suitable for separation and immobilization of Sr and Cs contained in acidic high-level liquid waste. The stabilities of published waste forms and their preparation processes were evaluated from the standpoint of conversion of exchangers containing Sr and Cs into appropriate waste forms. The essential results are below. (1) For separation and immobilization of Cs, crystalline silicotitanate seems to be the most promising exchanger. Insoluble ferrocyanides and phosphates are not suitable for immobilization without additives. Mordenite is inexpensive and commercially available but it would dissolve in highly acidic media. (2) For selective separation of Sr, there is no promising exchanger up to now. It is necessary either to modify separation condition or to synthesize a novel exchanger. (3) Soluble salts, glasses and ceramics are proposed as a storage or disposal form of separated Sr and Cs. Ceramics sintered by hot-pressing are favorable waste forms of inorganic ion-exchangers but their leachabilities and thermal conductivities are largely influenced by qualities of products. Crystallinity of a sintered exchanger depends on its composition. Exchanges of low Cs contents are often converted into amorphous materials whose chemical stabilities depend on solubilities of components of exchangers. (4) A new exchanger to be synthesized is crystalline and selective toward Sr and Cs. One meq/g is enough for Sr and Cs capacities, which are restricted by thermal and transmutation effects. Composition of the exchanger should be selected from the point of a scenario of separation and disposal. The solubilities of SiO{sub 2}, TiO{sub 2}, ZrO{sub 2}, Nb{sub 2}O{sub 5} and Ta{sub 2}O{sub 5} are low in acidic media and those of Al{sub 2}O{sub 3}, TiO{sub 2} and ZrO{sub 2}, in disposal circumstances. (5) Future works are optimization of separation scheme including development of exchangers, simplification of

  15. 磷酸镁水泥固化体中Sr2+、Cs+浸出性能及迁移模型研究%Study on the leaching performance and transport model of Sr2+, Cs+in magnesium phosphate cement

    Institute of Scientific and Technical Information of China (English)

    戴丰乐; 汪宏涛; 张时豪; 薛明; 丁建华; 姜自超

    2016-01-01

    采用磷酸镁水泥(Magnesium phosphate cement, MPC)对核素Sr2+、Cs+进行固化,对固化体中Sr2+、Cs+的浸出性能进行了研究,并根据Fick第二定律建立了适用于磷酸镁体系的Sr2+、Cs+迁移模型,对核素Sr2+、Cs+在磷酸镁水泥固化体中的迁移进行预测。结果表明,磷酸镁水泥可以有效固化Sr和Cs,使核素Sr2+、Cs+在磷酸镁水泥固化体中浸出率较低;建立的一维衰变浸出模型可以有效地预测核素Sr2+、Cs+在磷酸镁水泥固化体中的迁移规律。%Background:Magnesium phosphate cement (MPC) has a good application prospect in radioactive waste solidification for its good adsorption property of Sr and Cs which are the main elements in the middle and low level nuclear reactor waste. Purpose: This study aims to investigate the migration of radionuclides in MPC and build a transport model of Sr2+, Cs+in MPC. Methods:According to Fick’s second law, the migration model of Sr2+, Cs+to predict the leaching behavior of Sr2+, Cs+ was established by studying the leach abilities of Sr2+ and Cs+ in MPC. Results:Sr and Cs can be effectively solidified by MPC, and the leaching rate of Sr2+, Cs+is low. Compared with Sr2+, Cs+has stronger migration ability in magnesium phosphate cement. Conclusion:The leaching behavior of Sr2+, Cs+immobilized in MPC can be predicted well by one-dimension decay migration model. In addition, the migration behavior of Sr2+was predicted more accurately by the migration model.

  16. Microsphere zeolite materials derived from coal fly ash cenospheres as precursors to mineral-like aluminosilicate hosts for {sup 135,137}Cs and {sup 90}Sr

    Energy Technology Data Exchange (ETDEWEB)

    Vereshchagina, Tatiana A., E-mail: tatiana@icct.ru [Institute of Chemistry and Chemical Technology, Siberian Branch of the Russian Academy of Sciences, 50/24 Akademgorodok, Krasnoyarsk 660036 (Russian Federation); Vereshchagin, Sergei N., E-mail: snv@icct.ru [Institute of Chemistry and Chemical Technology, Siberian Branch of the Russian Academy of Sciences, 50/24 Akademgorodok, Krasnoyarsk 660036 (Russian Federation); Shishkina, Nina N., E-mail: ninash@icct.ru [Institute of Chemistry and Chemical Technology, Siberian Branch of the Russian Academy of Sciences, 50/24 Akademgorodok, Krasnoyarsk 660036 (Russian Federation); Vasilieva, Nataly G., E-mail: vng@icct.ru [Institute of Chemistry and Chemical Technology, Siberian Branch of the Russian Academy of Sciences, 50/24 Akademgorodok, Krasnoyarsk 660036 (Russian Federation); Solovyov, Leonid A., E-mail: leosol@icct.ru [Institute of Chemistry and Chemical Technology, Siberian Branch of the Russian Academy of Sciences, 50/24 Akademgorodok, Krasnoyarsk 660036 (Russian Federation); Anshits, Alexander G., E-mail: anshits@icct.ru [Institute of Chemistry and Chemical Technology, Siberian Branch of the Russian Academy of Sciences, 50/24 Akademgorodok, Krasnoyarsk 660036 (Russian Federation); Department of Chemistry, Siberian Federal University, 79 Svobodnyi Avenue, Krasnoyarsk 660041 (Russian Federation)

    2013-06-15

    Hollow microsphere zeolite materials with a bilayered zeolite/glass crystalline shell bearing NaP1 zeolite were synthesized by the hydrothermal treatment of coal fly ash cenospheres (Si/Al = 2.7) in an alkaline medium. Cs{sup +} and/or Sr{sup 2+} forms of zeolitized cenospheres with the different Cs{sup +} and/or Sr{sup 2+} loading were prepared by the ion exchange from nitrate solutions. The resulted (Cs,Na)P1, (Sr,Na)P1 and (Cs,Sr,Na)P1 bearing microsphere zeolites were converted to glass ceramics by heating at 900–1000 °C. The differential scanning calorimetry and quantitative phase analysis were used to monitor the solid-phase transformation of the initial and ion exchanged zeolite materials. It was established that the final solidified forms of Cs{sup +} and/or Sr{sup 2+} are glass–crystalline ceramic materials based on pollucite–nepheline, Sr-feldspar–nepheline and Sr-feldspar–pollucite composites including ∼60 wt.% of the major host phases (pollucite, Sr-feldspar) and 10–20 wt.% of glass. The {sup 137}Cs leaching rate of 4.1 × 10{sup −7} g cm{sup −2} day{sup −1} was determined for the pollucite glass–ceramic according to Russian State Standard (GOST) No. 52126 P-2003 (7 day, 25 °C, distilled water)

  17. Microsphere zeolite materials derived from coal fly ash cenospheres as precursors to mineral-like aluminosilicate hosts for 135,137Cs and 90Sr

    Science.gov (United States)

    Vereshchagina, Tatiana A.; Vereshchagin, Sergei N.; Shishkina, Nina N.; Vasilieva, Nataly G.; Solovyov, Leonid A.; Anshits, Alexander G.

    2013-06-01

    Hollow microsphere zeolite materials with a bilayered zeolite/glass crystalline shell bearing NaP1 zeolite were synthesized by the hydrothermal treatment of coal fly ash cenospheres (Si/Al = 2.7) in an alkaline medium. Cs+ and/or Sr2+ forms of zeolitized cenospheres with the different Cs+ and/or Sr2+ loading were prepared by the ion exchange from nitrate solutions. The resulted (Cs,Na)P1, (Sr,Na)P1 and (Cs,Sr,Na)P1 bearing microsphere zeolites were converted to glass ceramics by heating at 900-1000 °C. The differential scanning calorimetry and quantitative phase analysis were used to monitor the solid-phase transformation of the initial and ion exchanged zeolite materials. It was established that the final solidified forms of Cs+ and/or Sr2+ are glass-crystalline ceramic materials based on pollucite-nepheline, Sr-feldspar-nepheline and Sr-feldspar-pollucite composites including ˜60 wt.% of the major host phases (pollucite, Sr-feldspar) and 10-20 wt.% of glass. The 137Cs leaching rate of 4.1 × 10-7 g cm-2 day-1 was determined for the pollucite glass-ceramic according to Russian State Standard (GOST) No. 52126 P-2003 (7 day, 25 °C, distilled water).

  18. The Behaviour of 134Cs, 60Co, and 85Sr Radionuclides in Marine Environmental Sediment

    Directory of Open Access Journals (Sweden)

    Nariman H.M. Kamel

    2002-01-01

    Full Text Available This work describes experimental investigations and modelling studies on the sorption of radionuclides 134Cs, 60Co, and 85Sr by certain marine sediments within Egypt. The chemical composition of the marine sediments was determined. The soluble salts were measured for the sediments and the concentrations of the released cations, Al3+, Fe3+, and Si4+, were measured for the sediment materials in 0.1 M NaClO4 aqueous solution at different hydrogen ion concentrations. The two main factors that control the uptake of the radionuclides onto the sediment are the pH and the exchangeable capacities of the sediment materials. Surface complex model was used to estimate the surface charge densities and the electric surface potential of the marine sediment materials. These two parameters were calculated at the surface capacity sites of the sediment materials. The desorption of the adsorbed cations was determined by means of selective consecutive extraction tests using different chemical reagents including (1 1 M MgCl2 (pH 7, (2 1 M ammonium oxalate (pH 3-5, (3 0.04 M NH2OH,HCl in 25% acetic acid (pH 3-4, (4 H2O2 in 5% HNO3(pH 2-3, and (5 digestion with nitric acid followed by hydrofluoric and perchloric acids (pH 2.

  19. Evaluation of 226Ra, 232Th, 137Cs and 40K “Agaricus Bisporus” Activity in Cultivated Edible Mushroom formed in Tehran Province- Iran

    Directory of Open Access Journals (Sweden)

    Vahid Changizi

    2013-03-01

    Full Text Available Introduction Natural and man made radioactive sources exist in our environment they can enter into our food chains. One of these is the soil-mushroom-human chain. High level doses of natural radiation can cause hazards to humans. Materials and Methods Samples of Agaricus bisporus cultivated edible mushroom in Tehran province- Iran were collected from 7 farms. Specific activity of 226Ra, 228Ra, 137Cs, 40K and 235U of the samples were measured by two HPGe detectors. Results Specific activity of 226Ra, 228Ra, 137Cs and 40K in the edible mushroom samples were equal to 0.06 ± 0.03 - 0.7 ± 0.2 Bq kg-1 dry, 1.4 ± 0.7 Bq kg-1 dry, 0.1 ± 0.03- 0.3 ± 0.1 Bq kg-1dry and 920 ± 400 - 1370 ± 900 Bq kg-1dry , respectively. Conclusion As the measured concentrations of the radionuclides of interest are close or lower than MDA (Minimum Detectable Activity. Consumption of the mushrooms would impose no health consequences to the consumers.

  20. A preliminary study for the development of reference material using oyster for determination of (137)Cs, (90)Sr and plutonium isotopes.

    Science.gov (United States)

    Lee, Sang-Han; Oh, Jung-Suk; Lee, Jong-Man; Lee, Kyung-Bum; Park, Tae-Soon; Lee, Min-Kie; Kim, Seung-Hwan; Choi, Jong-Ki

    2016-03-01

    A new reference material for the determination of (137)Cs, (90)Sr and Pu isotopes ((238)Pu and (239,240)Pu) is being developed using dried oyster matrix by Korea Research Institute of Standards and Science (KRISS). The oyster was collected from Tongyoung harbour, southern part of Korea and the artificial radionuclides ((137)Cs, (90)Sr, (238)Pu and (239,240)Pu) were spiked into the material. After pretreatment and processing, the material was tested for homogeneity and massic activities were determined by measuring (137)Cs, (90)Sr, (238)Pu and (239,240)Pu. The reference value and extended uncertainty for those isotopes will be reported later.

  1. Sorption capacity studies of Scheldt sediments for /sup 60/Co, /sup 85/Sr, and /sup 137/Cs

    Energy Technology Data Exchange (ETDEWEB)

    Meeussen, M.A.; Willems, G.J.; De Ranter, C.J.

    1975-01-01

    Using /sup 60/Co, /sup 85/Sr and /sup 137/Cs as tracer ions the sorption capacity of Scheldt sediments for Co/sup 2 +/, Sr/sup 2 +/ and Cs/sup +/ was studied and their distribution coefficients between sediment and Scheldt water were determined. It is found that clay and silt samples show relatively high sorption capacities for cobalt and cesium, compared with the low fixation rate for strontium. The selectivity of the sediments for a particular ion, in competition with other ions, was studied and the sequence found is in accordance with the distribution coefficients. From these experiments it may be concluded that the high salt concentrations, present in normal Scheldt water, will limit the risks of radioactive isotopes accumulation in the sediments.

  2. СONTAMINATION OF 137CS AND 90SR OF THE FOREST FOODSTUFFS IN THE BRYANSK REGION

    Directory of Open Access Journals (Sweden)

    K. V. Shilova

    2010-01-01

    Full Text Available The present work is devoted to the analysis of appropriateness's of accumulation and estimation of migration of 137Cs and 90Sr in the forest foodstuffs sampled in the Sought-Eastern areas of the Bryansk region. Comparing of the results of estimation of the investigated forest foodstuffs contamination degree with hygienic requirements allows finding out the possibility of their safe consumption by population living in the territory under investigation.

  3. A pilot study on the transfer of {sup 137}Cs and {sup 9}Sr to horse milk and meat

    Energy Technology Data Exchange (ETDEWEB)

    Semioshkina, N. [GSF-Institut fuer Strahlenschutz, Postfach 1129, D-85788 Neuherberg (Germany)]. E-mail: semi@gsf.de; Voigt, G. [Agency' s Laboratories - Seibersdorf, IAEA, 1400-Vienna (Austria)]. E-mail: g.voigt@iaea.org; Fesenko, S. [Agency' s Laboratories - Seibersdorf, IAEA, 1400-Vienna (Austria)]. E-mail: s.fesenko@iaea.org; Savinkov, A. [Scientific Research Agricultural Institute of the National Biotechnology Center, Ministry for Science and Higher Education of the Republic of Kazakhstan (SRAI), 480544 Gvardeiski (Kazakhstan)]. E-mail: chebotar@srai.kz; Mukusheva, M. [National Nuclear Centre of Republic of Kazakhstan, Kurchatov 490021 (Kazakhstan)]. E-mail: mukusheva@nnc.kz

    2006-07-01

    The radiological assessment of the impact of nuclear weapon's testing on the Semipalatinsk Test Site (STS) on the local population requires comprehensive site-specific information on radionuclide behaviour in the environment. However, information on radionuclide behaviour in the conditions of the STS is rather sparse and, in particular, there are no data in the literature on parameters of radionuclide transfer from feed to horse products proofed to be important contributors to the internal dose to the local population. The transfer of {sup 137}Cs and {sup 9}Sr to horse milk and meat was studied under laboratory and field conditions: in controlled experiment with three lactating horses maintained in the Kazakh Agricultural Research Institute, and in field measurements of horse products taken from horses grazing at the Semipalatinsk Test Site. The equilibrium transfer factors from feed to horse milk and meat were estimated to be 0.012 d l{sup -1} and 0.035 d kg{sup -1} for {sup 137}Cs and 0.0022 d l{sup -1} and 0.003 d kg{sup -1} for {sup 9}Sr, respectively. The biological half-lives were approximated by a sum of two exponentials amounting to 3 (85%) and 15 (15%) days for {sup 137}Cs and 3.5 (70%) and 100 (30%) days for {sup 9}Sr. The highest {sup 137}Cs transfer has been found to be to spleen, followed by lung, heart, muscles, kidneys, intestine, and finally skin and bones. For {sup 9}Sr, the maximum activity concentration was observed in bones; contamination of other tissues is rather uniform except for liver and intestine with a factor of about 2 higher than muscles.

  4. Adsorption and desorption of 85Sr and 137Cs on reference minerals, with and without inorganic and organic surface coatings.

    Science.gov (United States)

    Bellenger, Jean-Philippe; Staunton, Siobhán

    2008-05-01

    The adsorption properties of reference minerals may be considerably modified by the presence of the inorganic and organic coatings that are ubiquitous in soils. It is therefore important to assess the effect of such coatings to evaluate the relevance of adsorption studies on pure minerals. The adsorption of trace amounts of (85)Sr and (137)Cs has been studied in dilute suspensions for various minerals that are common components of soils: quartz, calcium carbonate, kaolinite, montmorillonite and illite. We studied the effect of coatings with either Fe or Al oxide with varying additions of soil-extracted humic or fulvic acid. Both adsorption and desorption were measured and data presented as distribution coefficients, Kd. No adsorption was detected on quartz and it was not possible to coat this surface. Adsorption on calcium carbonate was small and not influenced by coatings. Adsorption of Sr on the three clay minerals was very similar, enhanced by the Al-coating, but not affected by Fe and organic coatings. The presence of organic coatings decreased Cs adsorption on illite. Similar but smaller effects were seen on montmorillonite and kaolinite. Aluminum coating enhanced Cs adsorption on illite, whereas both inorganic coatings caused decreases in adsorption on montmorillonite, and there was no effect on kaolinite. Effects were not additive with mixed, organic-inorganic coatings. Adsorption of both Cs and Sr on all minerals was strongly irreversible, with Kd (desorption) being up to four-times greater than adsorption Kd. The ratio of desorption and adsorption Cs Kd values (an assessment of irreversibility) was inversely related to adsorption Kd. This is consistent with a decreasing contribution of high-affinity adsorption as adsorption increases, but may also reflect the partial loss of organic coatings during desorption.

  5. Continuous decline of background activity concentrations of {sup 3}H, {sup 90}Sr and {sup 137}Cs in hydrosphere

    Energy Technology Data Exchange (ETDEWEB)

    Juranova, E.; Hanslik, E.; Maresova, D. [T.G. Masaryk Water Research Institute (Czech Republic)

    2014-07-01

    Main artificial radionuclides - {sup 3}H, {sup 90}Sr and {sup 137}Cs - have occurred in environment since atmospheric tests of nuclear weapons, and later in Europe, since the accident at the Chernobyl nuclear reactor. Hence, these radionuclides can still be detected in samples of surface water and other components of hydrosphere. To assess environmental impact of nuclear facilities, which represent point sources of artificial radioactivity, it is necessary to take into account a decreasing trend of the radionuclides background, observed in water, bottom sediments and biota. The paper describes development of {sup 3}H, {sup 90}Sr and {sup 137}Cs concentrations and balances through an example of vicinity of the Temelin Nuclear Power Plant in South Bohemia in pre-operational (1990-2000) and operational (2001-2012) stage. The concentrations of {sup 137}Cs and {sup 90}Sr were permanently decreasing during the monitored period and they cover up the same radionuclides released from the plant. In addition, similar decreasing trend was observed for tritium concentrations in river sites, which were not affected by the plant, too. In contrast to the other radionuclides, concentrations of tritium detected at the sites affected by the plant were substantially above its background. Document available in abstract form only. (authors)

  6. Bioaccumulation of the artificial Cs-137 and the natural radionuclides Th-234, Ra-226, and K-40 in the fruit bodies of Basidiomycetes in Greece.

    Science.gov (United States)

    Kioupi, Vasiliki; Florou, Heleny; Kapsanaki-Gotsi, Evangelia; Gonou-Zagou, Zacharoula

    2016-01-01

    The bioaccumulation of artificial Cs-137 and natural radionuclides Th-234, Ra-226, and K-40 by Basidiomycetes of several species is studied and evaluated in relation to their substratum soils. For this reason, 32 fungal samples, representing 30 species of Basidiomycetes, were collected along with their substratum soil samples, from six selected sampling areas in Greece. The fungal fruit bodies and the soil samples were properly treated and the activity concentrations of the studied radionuclides were measured by gamma spectroscopy. The measured radioactivity levels ranged as follows: Cs-137 from Ra-226 from <0.3 to 1.0 ± 0.5 Bq kg(-1) F.W., and K-40 from 56.4 ± 3.0 to 759.0 ± 28.3 Bq kg(-1) F.W. The analysis of the results supported that the bioaccumulation of the studied natural radionuclides and Cs-137 is dependent on the species and the functional group of the fungi. Fungi were found to accumulate Th-234 and not U-238. What is more, potential bioindicators for each radionuclide among the 32 species studied could be suggested for each habitat, based on their estimated concentration ratios (CRs). The calculation of the CRs' mean values for each radionuclide revealed a rank in decreasing order for all the species studied.

  7. Measurements of {sup 137}Cs and {sup 90}Sr in Swedish consumption milk between 1991 1996; Maetningar av {sup 137}Cs och {sup 90}Sr i konsumtionsmjoelk mellan 1991 och 1996

    Energy Technology Data Exchange (ETDEWEB)

    Moere, H.

    1997-04-01

    The sources for the radioactivity are the nuclear weapons tests and the Chernobyl accident in 1986. Milk is sampled and measured as an important indicator of the Chernobyl load of radionuclides that cows can metabolize and that will ultimately give a dose to humans. Milk was responsible for 13-19% of the total intake of {sup 137}Cs from foodstuffs for the average person in 1994. Our milk measurement program covered 90% of all produced consumption milk in Sweden in 1995. Milk samples are taken every second month from the dairies. {sup 90}Sr is only measured on pooled yearly samples from some dairies; these dairies covered 50% of the total production of consumption milk in Sweden in 1995. The mean value per year of {sup 137}Cs for the whole country has decreased from 0.52 to 0.26 Bq/l between 1991 and 1996, which corresponds to a committed effective dose equivalent for humans of 1.1-0.50 microSv for {sup 137}Cs. For {sup 90}Sr during the 1991-1996 period the country-wide mean varied between 0.08 and 0.06 Bq/l, resulting in a committed effective dose equivalent of 0.4-0.3 microSv. 7 refs.

  8. Effects of melt aging and off-stoichiometric melts on CsSrI3:Eu(2+) single crystal scintillators.

    Science.gov (United States)

    Wu, Yuntao; Zhuravleva, Mariya; Johnson, Jesse Ashby; Wei, Hua; Koschan, Merry; Melcher, Charles L

    2016-03-28

    Ternary halide scintillators are commonly prepared from a mixture of commercially available binary halides. The initial binary halides may contain excess halogen ions or have different volatilities, which could lead to loss of stoichiometry of the resulting ternary halide crystals and potentially negatively affect optical and scintillation properties. In this work, the effects of vacuum aging of the melt (melt aging) and use of off-stoichiometric melts via introduction of excess CsI on the crystal quality and scintillation properties of CsSrI3:Eu(2+), a promising scintillator for gamma-ray detection applications, are investigated. The phase purity of the grown samples was confirmed by powder X-ray diffraction and differential scanning calorimeter measurements, and the existence of matrix composition variations is revealed by energy-dispersive X-ray spectroscopy analyses. An abnormal relationship between the full energy peak and the shaping time, i.e. full energy peak broadening or existence of two full energy peaks, in the melt-aged and off-stoichiometric samples is observed. It is ascribed to a slow scintillation decay event in a time scale between 15 and 50 μs. For the CsSrI3:Eu(2+) single crystal grown from a stoichiometric melt without melt aging treatment, an energy resolution of 5.0% at 662 keV and a light yield of 48,000 ± 2000 photons per MeV can be achieved at a size of 1.4 cm(3).

  9. Analysis of 226Ra, 232Th 40К and 137Cs in samples of soil from some areas of Republic of Macedonia by using gamma spectrometry

    Directory of Open Access Journals (Sweden)

    Todorovik Aleksandra

    2012-01-01

    Full Text Available Taking into consideration the importance of the distribution and transfer of radio nuclides in soil, an attempt was made in this work to determine the concentration of 226Ra, 232Th 40К and 137Cs in the same. The concentrations of activity in the gamma-absorbed dose rates of the terrestrial naturally occurring radio nuclides, as follows, 226Ra, 232Th and 40K were determined in samples of soil collected from some parts of Republic of Macedonia, i.e. from three major cities in the Republic of Macedonia. The samples are taken by means of a special dosage dispenser which enables sampling of samples at a depth of 0-5 cm, 5-10cm and 10-15cm, thus disabling the sampling above these layers of soil. An identification of radio nuclides and assessment of their activity has been performed by applying gamma spectrometry. The time of counting for each sample was 65000 s. in order to obtain statistically small mistake. The spectrums were analyzed by a commercially available software GENIE-2000 received from Canberra, Austria. The activity of soil had wide range of values: 20.3 to 82.9 Bq kg-1for 226Ra, 16.1 to 82.5 Bq kg-1 for 232Th, 325 to 799.0 Bq kg-1for 40К and 9.1 to 24.3 Bq kg-1for 137Cs, respectively. The concentrations of these radio nuclides have been compared with the available data from the other countries. Natural environmental radioactivity and the associated external exposure due to gamma radiation depend primarily on the geological and geographical conditions. Namely, the specific levels of terrestrial environmental radiation are related to the type of rocks from which the soils originate. The obtained data indicate that the average value of activity of 232Th is about higher than the one of 226Ra The concentration of activity of 40К in the soil has greater value than 32Th and 226Ra in all soils. The causes for the existence of 137Cs in these soils are the nuclear explosions, waste radioactive materials and other incidents. It reaches the

  10. Accumulation and transfer of 137Cs and 90Sr in the plants of the forest ecosystem near the Ignalina Nuclear Power Plant.

    Science.gov (United States)

    Lukšienė, B; Marčiulionienė, D; Gudelienė, I; Schönhofer, F

    2013-02-01

    The radioecological state of the forest ecosystem in the vicinity of the Ignalina Power Plant prior to decommissioning was analysed with specific emphasis on (137)Cs and (90)Sr activity concentrations in plant species growing in two reference sampling sites (Tilze and Grikiniskes). In the period of 1996-2008 the mean contamination of plants with (137)Cs was from 45 to 119 Bq/kg and with (90)Sr - from 3 to 42 Bq/kg. Measured (137)Cs TF values for soil-root transfer mainly ranged between 1.0-1.4, except for Calamagrostis arundinacea which had a TF value of 0.1. On average, the (137)Cs TF value from root to shoot was 1.7 fold higher than for soil to root transfer. (90)Sr TF values (soil-root) were in the range of 1.2-1.8 but for Calluna vulgaris it was 0.2. The mean root to shoot TF value for (90)Sr was 7.7 fold higher. These results indicate the higher (90)Sr bioavailability than that of (137)Cs in the forested area. The Grikiniskes reference site is located nearby the Ignalina NPP, specifically the heated water outlet channel, which results in altered microclimatic conditions. These specific microclimatic conditions result in relationships between (137)Cs TF (soil-root) values and pH, moisture and organic matter content in the soil at Grikiniskes which appear to be different to those at the Tilze reference sampling site.

  11. Migration of (137)Cs, (90)Sr, and (239+240)Pu in Mediterranean forests: influence of bioavailability and association with organic acids in soil.

    Science.gov (United States)

    Guillén, J; Baeza, A; Corbacho, J A; Muñoz-Muñoz, J G

    2015-06-01

    The understanding of downward migration of anthropogenic radionuclides in soil is a key factor in the assessment of their environmental behavior. There are several factors that can affect this process, such as the radionuclide source, their chemical form, soil and environmental characteristics, etc. Two Mediterranean pinewood ecosystems in Spain, which were affected mainly by global fallout, were selected to assess the migration of (137)Cs, (90)Sr, and (239+240)Pu. Using auxiliary modeling (diffusion-convection equation and compartmental model), it followed from field observations that the migration velocities of (90)Sr and (239+240)Pu were similar and higher than that of (137)Cs. The downward migration of radionuclides can be considered a consequence of their association with soil particles. A sequential speciation procedure also confirmed that (90)Sr was the most bioavailable radionuclide followed by (239+240)Pu and (137)Cs. Although this can explain the different velocity of (90)Sr and (137)Cs, bioavailability could not explain by itself the similar velocities of (239+240)Pu and (90)Sr. The presence of organic acids in the soil can also influence the migration of radionuclides attached to them, which decreased in the order: (239+240)Pu > (90)Sr > (137)Cs. Thus, the joint consideration of bioavailable and humic + fulvic acid fractions can explain the observed differences in the downward velocities.

  12. A design study for the analysis of 90Sr And 135,137Cs by ISA-AMS

    Science.gov (United States)

    Alary, Jean-François; Cousins, Lisa M.; Eliades, John; Hao, Changtong; Javahery, Gholamreza; Kieser, William E.; Litherland, Albert E.; Zhao, Xiaolei

    2013-04-01

    Extending the range of Accelerator Mass Spectrometry (AMS) to the fission products 90Sr and 135,137Cs would offer numerous advantages for non-proliferation surveillance activities. A new method for suppressing the interfering isobars 90Zr (and 90Y) and 135,137Ba using low kinetic energy (Anions (ISA). Combined with fluoridematrix assisted ionization, this method greatly improves the analytical capabilities of AMS for 90Sr and will enable the direct analysis of 135,137Cs below sub-parts per trillion levels. The ISA alone provides interference suppression factors of 4×10-6 for ZrF3-/SrF3- and 2×10-5 for BaF2-/CsF2-. The general performance improvement provided by the ISA, however, critically depends on the capacity of this device to transmit the wanted anions with a high efficiency and with a stable response to the natural variations of AMS targets. Based on recent SIMION-8.1 studies and on results of a parallel study on the attenuation of other anions, we have developed a pre-commercial design for the ISA. In this design, RFQ rods and split-flow turbo molecular pumps are configured to achieve full control of reaction time, ion energy and fragmentation pathways (chemical and kinetic reactions), and to improve beam transmission through the cell. The mechanical layout will be presented in 3D models using Solid Works; SIMION-8.1 simulations were used to illustrate the importance of optical matching of the RFQ and the front-end DC retardation section of the ISA.

  13. Correlated Absorbtion between Sr or Cs and other Elements of Plants%植物吸收Sr、Cs与其他元素的相关性研究

    Institute of Scientific and Technical Information of China (English)

    江世杰; 唐永金; 赵萍

    2012-01-01

    Under treatment of high concentration Sr or Cs, the correlation between Sr, Cs and other elements absorbtion of plants was studied using X-ray fluorescence spectrometer determining the relative content of various elements of aerial parts of plants. The results showed that there was very significant positive correlation between Sr and Ca, Mg, significant correlation betwwen S and Na under the treatment of high concentration Sr; there was also very significant negative correlation between Sr and P, Si, Fe, Zn, and significant negative correlation between Sr and K, Al in plants. Under the treatment of high concentration Cs, no significant absorbtion correlation was showed between Cs and other elements, and the correlation between Cs and K was the highest with correlation cofficient 0.661 4. Without treatment of Sr and Cs, a little of Sr was absorbed by plants and there were positive correlations between Sr and Ca, Cl, Mg, Na, Fe, Al, Zn, but only the correlation between Sr and Ca was significant. Therefore, the correlation between Sr or Cs and other elements absorbed by plants was different, which was noteworthy in phytoremediation.%用高浓度的Sr或Cs处理土壤,采用X射线荧光光谱仪(XRF)测定植物地上部分各元素的相对含量,研究植物吸收Sr、Cs与其他元素的相关性.结果表明,高浓度Sr处理下,植物吸收Sr与Ca、Mg呈极显著正相关,与S、Na呈显著正相关,与P、Si、Fe、Zn呈极显著负相关,与K、Al呈显著负相关;高浓度Cs处理下,植物吸收Cs与其他元素的相关性均不显著,但与K的相关系数较大,为0.6614;不施核素处理下,植物吸收微量的Sr,吸收Sr与Ca、Cl、Mg、Na、Fe、Al、Zn呈正相关,但只与Ca显著相关.因此,植物吸收Sr、Cs与其他元素有不同的相关性,在土壤核素污染的植物修复中值得注意.

  14. {sup 137}Cs and {sup 90}Sr behaviour in contaminated soils of the Chernobyl area; Etude du comportement du {sup 137}Cs et du {sup 90}Sr dans les sols contamines de la region de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Gri, N. [CEA/Fontenay-aux-Roses, Inst. de Protection et de Surete Nucleaire (IPSN), 92 (France)]|[Paris-11 Univ., 91 - Orsay (France)

    2000-07-01

    The improvement of the understanding of the mechanisms which generate radionuclides retention in soils are of main importance for radioactivity transport models, especially for long time assessments. In this context, the objectives of this thesis were to identify the mechanisms responsible for {sup 137}Cs and {sup 90}Sr behaviour in non cultivated soils and to quantify their influence. We studied radiocaesium and radiostrontium availability in different soils of the Chernobyl area (chernozem, sand, gley, peat), whose contamination took several physico-chemical forms (fuel particles, condensed forms, mixed deposits). The migration profiles obtained by gamma spectrometry and liquid scintillation show that the majority of the activity is contained in the ten first centimeters of soil, except for one site. The profiles are varied and don't allow to classify the radionuclides availability according to the pedology or to the contamination type. A selective extraction protocol applied on several soil layers has been adopted as an indirect approach. Although radionuclides availability is increasing with depth, the selective extraction protocol shows that a non negligible fraction of activity remain not mobile. {sup 137}Cs is associated to interstratified clay minerals in a non reversible way and {sup 90}Sr is strongly bound to fuel particles. The existence of these retention mechanisms calls into question the use of the K{sub d} distribution coefficient in transport models because they disabled reversibility and instantaneous desorption notions. (author)

  15. Plutonium, {sup 137}Cs and {sup 90}Sr in selected invertebrates from some areas around Chernobyl nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Mietelski, Jerzy W., E-mail: jerzy.mietelski@ifj.edu.p [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Krakow (Poland); Maksimova, Svetlana, E-mail: soilzool@biobel.bas-net.b [Institute of Zoology, National Academy of Sciences, Akademicheskaya 27, 220072 Minsk (Belarus); Szwalko, Przemyslaw [Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Slawkowska 17, 31-016 Krakow (Poland); Wnuk, Katarzyna [Holycross Cancer Center, Department on Nuclear Medicine, Artwinskiego 3, 25-734 Kielce (Poland); Zagrodzki, Pawel [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Krakow (Poland); Department of Food Chemistry and Nutrition, Medical College, Jagiellonian University, Medyczna 9, 30-688 Krakow (Poland); Blazej, Sylwia; Gaca, Pawel; Tomankiewicz, Ewa [The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Krakow (Poland); Orlov, Olexandr, E-mail: station@zt.ukrpack.ne [Poleskiy Branch of Ukrainian Scientific Research Institute of Forestry and Agro-Forest-Amelioration, Prospect Mira 38, Zhytomyr 10004 (Ukraine)

    2010-06-15

    Results are presented for {sup 137}Cs, {sup 90}Sr and plutonium activity concentrations in more than 20 samples of terrestrial invertebrates, including species of beetles, ants, spiders and millipedes, collected in the highly contaminated area of the Chernobyl exclusion zone. The majority of samples were collected in Belarus, with some also collected in the Ukraine. Three other samples were collected in an area of lower contamination. Results show that seven samples exceed an activity concentration of 100 kBq/kg (ash weight - a.w.) for {sup 137}Cs. The maximum activity concentration for this isotope was 1.52 +- 0.08 MBq/kg (a.w.) determined in ants (Formica cynerea). Seven results for {sup 90}Sr exceeded 100 kBq/kg (a.w.), mostly for millipedes. Relatively high plutonium activity concentrations were found in some ants and earth-boring dung beetles. Analyses of activity ratios showed differences in transfer of radionuclides between species. To reveal the correlation structure of the multivariate data set, the Partial Least-Squares method (PLS) was used. Results of the PLS model suggest that high radiocesium activity concentrations in animal bodies can be expected mainly for relatively small creatures living on the litter surface. In contrast, high strontium activity concentrations can be expected for creatures which conduct their lives within litter, having mixed trophic habits and a moderate lifespan. No clear conclusions could be made for plutonium.

  16. Plutonium, 137Cs and 90Sr in selected invertebrates from some areas around Chernobyl nuclear power plant.

    Science.gov (United States)

    Mietelski, Jerzy W; Maksimova, Svetlana; Szwałko, Przemysław; Wnuk, Katarzyna; Zagrodzki, Paweł; Błazej, Sylwia; Gaca, Paweł; Tomankiewicz, Ewa; Orlov, Olexandr

    2010-06-01

    Results are presented for (137)Cs, (90)Sr and plutonium activity concentrations in more than 20 samples of terrestrial invertebrates, including species of beetles, ants, spiders and millipedes, collected in the highly contaminated area of the Chernobyl exclusion zone. The majority of samples were collected in Belarus, with some also collected in the Ukraine. Three other samples were collected in an area of lower contamination. Results show that seven samples exceed an activity concentration of 100 kBq/kg (ash weight--a.w.) for (137)Cs. The maximum activity concentration for this isotope was 1.52+/-0.08 MBq/kg (a.w.) determined in ants (Formica cynerea). Seven results for (90)Sr exceeded 100 kBq/kg (a.w.), mostly for millipedes. Relatively high plutonium activity concentrations were found in some ants and earth-boring dung beetles. Analyses of activity ratios showed differences in transfer of radionuclides between species. To reveal the correlation structure of the multivariate data set, the Partial Least-Squares method (PLS) was used. Results of the PLS model suggest that high radiocesium activity concentrations in animal bodies can be expected mainly for relatively small creatures living on the litter surface. In contrast, high strontium activity concentrations can be expected for creatures which conduct their lives within litter, having mixed trophic habits and a moderate lifespan. No clear conclusions could be made for plutonium. Copyright (c) 2008 Elsevier Ltd. All rights reserved.

  17. Glass waste forms for heat-generating Cs{sup +} and Sr{sup 2+} wastes from pyro-processing

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Min Suk; Heo, Jong [POSTECH, Pohang (Korea, Republic of); Park, Hwan Seo [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    Pyro-processing is one of the promising recycling technologies for spent nuclear fuel (SNF) from Light Water Reactors (LWR) in Korea. This processing is able to separate radioactive waste nuclei and reduce heat loading in storage site by extraction of heat generating radioactive nuclei. In this study, we used alumino-borosilicate glasses for the immobilization of Cs{sub 2}O and SrO wastes. Glasses were prepared and their important properties including chemical durability were analyzed. In addition, heat generation and its effect on thermal stability of glasses was examined. Glass waste forms that contain heat-generating Cs{sup +} and Sr{sup 2+} from pyro-processing were synthesized. Basic properties of glasses such as densities, linear expansion coefficients and glass-transition temperatures were similar to those of industrial radioactive waste glass. Analysis on the heat load simulation under the failure of the cooling system indicated that maximum temperature inside the canisters are well below the glass-transition temperature of each glass.

  18. Quantifying sediment sources in a lowland agricultural catchment pond using {sup 137}Cs activities and radiogenic {sup 87}Sr/{sup 86}Sr ratios

    Energy Technology Data Exchange (ETDEWEB)

    Le Gall, Marion; Evrard, Olivier [Laboratoire des Sciences et de l' Environnement, UMR 8212 (CEA/CNRS/UVSQ), Université Paris-Saclay, Domaine du CNRS, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex (France); Foucher, Anthony [E.A 6293, Laboratoire GéoHydrosystèmes Continentaux (GéHCO), Université F. Rabelais de Tours, Faculté des Sciences et Techniques, Parc de Grandmont, 37200 Tours (France); Laceby, J. Patrick [Laboratoire des Sciences et de l' Environnement, UMR 8212 (CEA/CNRS/UVSQ), Université Paris-Saclay, Domaine du CNRS, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex (France); Salvador-Blanes, Sébastien [E.A 6293, Laboratoire GéoHydrosystèmes Continentaux (GéHCO), Université F. Rabelais de Tours, Faculté des Sciences et Techniques, Parc de Grandmont, 37200 Tours (France); Thil, François; Dapoigny, Arnaud; Lefèvre, Irène [Laboratoire des Sciences et de l' Environnement, UMR 8212 (CEA/CNRS/UVSQ), Université Paris-Saclay, Domaine du CNRS, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex (France); Cerdan, Olivier [Département Risques et Prévention, Bureau de Recherches Géologiques et Minières, 3 avenue Claude Guillemin, 45060 Orléans (France); and others

    2016-10-01

    Soil erosion often supplies high sediment loads to rivers, degrading water quality and contributing to the siltation of reservoirs and lowland river channels. These impacts are exacerbated in agricultural catchments where modifications in land management and agricultural practices were shown to accelerate sediment supply. In this study, sediment sources were identified with a novel tracing approach combining cesium ({sup 137}Cs) and strontium isotopes ({sup 87}Sr/{sup 86}Sr) in the Louroux pond, at the outlet of a lowland cultivated catchment (24 km{sup 2}, Loire River basin, France) representative of drained agricultural areas of Northwestern Europe. Surface soil (n = 36) and subsurface channel bank (n = 17) samples were collected to characterize potential sources. Deposited sediment (n = 41) was sampled across the entire surface of the pond to examine spatial variation in sediment deposits. In addition, a 1.10 m sediment core was sampled in the middle of the pond to reconstruct source variations throughout time. {sup 137}Cs was used to discriminate between surface and subsurface sources, whereas {sup 87}Sr/{sup 86}Sr ratios discriminated between lithological sources. A distribution modeling approach quantified the relative contribution of these sources to the sampled sediment. Results indicate that surface sources contributed to the majority of pond (μ 82%, σ 1%) and core (μ 88%, σ 2%) sediment with elevated subsurface contributions modeled near specific sites close to the banks of the Louroux pond. Contributions of the lithological sources were well mixed in surface sediment across the pond (i.e., carbonate sediment contribution, μ 48%, σ 1% and non-carbonate sediment contribution, μ 52%, σ 3%) although there were significant variations of these source contributions modeled for the sediment core between 1955 and 2013. These fluctuations reflect both the progressive implementation of land consolidation schemes in the catchment and the eutrophication of

  19. The radiological exposure of man from ingestion of Cs-137 and Sr-90 in seafood from the Baltic Sea. Pilot project: Marina-Balt

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, S.P. [Risoe National Lab., Roskilde (Denmark); Oehlenschlaeger, M. [National Institute of Radiation Hygiene, Broenshoej (Denmark); Karlberg, O. [Swedish Radiation Protection Institute, Stockholm (Sweden)

    1995-04-01

    This report describes a limited radiological assessment of the collective doses to man from the intake of seafood from the Baltic Sea contaminated with the radionuclides Cs-137 and Sr-90. Information on fisheries statistics is presented. The most important source terms to radioactive contamination of Cs-137 and Sr-90 in the Baltic Sea are identified and quantified. A compartment model for the dispersion of radionuclides in European coastal waters including the Baltic Sea is described and tested by comparing model predictions with observations. Collective doses are calculated with the model for each of the source-term categories. (au) (11 tabs., 28 ills., 17 refs.).

  20. Assessment of (226)Ra, (238)U, (232)Th, (137)Cs and (40)K activities from the northern coastline of Oman Sea (water and sediments).

    Science.gov (United States)

    Darabi-Golestan, F; Hezarkhani, A; Zare, M R

    2017-02-27

    Water and sediment samples were collected from northern coast of Oman Sea covering from Goatr to Hormoz canyon seaport. Water and sediment quality assessment for naturally or anthropogenic radionuclides at Oman Sea as a main strategic golf for trade and transit, is an important issue. Correspondence analysis (CA) by R-mode analysis represents that sigma(T)-temperature-conductivity-O2 parameters are well-correlated with (226)Ra, (232)Th and (40)K. Accordingly Q-mode analysis revealed an indicator samples of ST13W for different radionuclides, ST03W for O2, and simultaneously ST34W-ST21W-ST08W-ST04W for sigma(T) parameters. The CA results overlapped with factor and cluster analysis results that explained 85.8% of total variance of water samples. Descriptive analysis of sediments indicates more significant variation than water samples. The (232)Th and (226)Ra generally showing that ST13D to ST25D sediments that restricted to Pi Bashk coastline are concentrated from (137)Cs and (40)K. By comparison with reference-values from Iran and other parts of the world, they are acceptable with respect to environmental and radioisotope hazards.

  1. [The forecasting of vertical distribution of 37Cs and 90Sr in the forest soils of the Republic of Belarus].

    Science.gov (United States)

    Perevolotskiĭ, A N; Perevolotskaia, T V

    2012-01-01

    The study analyzes the distribution of 137Cs and 90Sr in the vertical profile of soil of forest biogeocenoses with different modes of moisture and species composition of woody vegetation on the "long" trail of radioactive fallout in the Republic of Belarus. The parameters of radionuclide migration are calculated for the two component quasi-diffusion equation, also based on this equation, pollution of root zone soil layers is predicted, as well as semi-refined periods and the contribution of migration in this process are defined. The intensity of radionuclide migration in the vertical profile of forest soils is found to increase with the change of the soil moisture regime from automorphic to hydromorphic.

  2. HYGIENIC STANDARDS FOR CS-137 AND SR-90 IN THE FOODSTUFFS: EXPERIENCE OF BELARUS AFTER THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    J. E. Kenigsberg

    2008-01-01

    Full Text Available The article presents results of analysis for development and implementation of the national permissible levels for Cs-137 and Sr-90 contamination of the foodstuff and water. These permissible levels were introduced in Belarus after the accident at the Chernobyl NPP as a protective measure to limit the doses of internal exposure. The article also contains comparison between numerical values of permissible levels introduced in Belarus, Ukraine and Russian as well as between the potential doses of internal exposure which could be formed while consuming the contaminated foodstuff with the levels of contamination equal to the permissible levels. The possibilities for harmonization of the permissible levels in three countries are discussed. The expediency of establishing quotes for doses of internal and external exposure is considered.

  3. References to Studies of 137Cs, 90Sr and 239+240Pu in the Pacific Ocean a Bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.

    2001-02-01

    This report contains a listing of publications known to this author on reported concentrations, reviews and discussions of {sup 137}Cs, {sup 90}Sr and {sup 239+240}Pu in seawater, sediment and the biota from parts of the North and South Pacific Ocean. Each reference has been assigned an accession number consisting of the first three letters of the first author's last name followed by the first letter of the first name, the year of the publication and an assigned number. Studies in both the coastal areas and the open ocean are included as well as those providing data within lagoons of coral atolls. Some references to the radionuclides in the Indian Ocean are also provided.

  4. Long-term behaviours of {sup 54}Mn, {sup 60}Co, {sup 85}Sr and {sup 137}Cs in a simulated rice field

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Y. H.; Lim, K. M.; Park, H. G; Park, D. W.; Lee, W. Y. [KAERI, Taejon (Korea, Republic of)

    1999-07-01

    or studying long-term behaviours of major fission and activation products in the paddy field, greenhouse experiments were carried out for 4 years with rice plants grown in a simulated paddy field. A radioactive solution containing {sup 54}Mn, {sup 60}Co, {sup 85}Sr and {sup 137}Cs was mixed with the topsoil in a flooded lysimeter 1 day before transplanting rice seedlings in 1993. Soil-to-plant transfer factor (TFs) of {sup 54}Mn and {sup 85}Sr were 1-2 orders of magnitude higher than those of {sup 60}Co and {sup 137}Cs. TFs of {sup 54}Mn and {sup 137}Cs tended to decrease year by year but that of {sup 60}Co decreased a little only in the second year. Negligible amounts of {sup 54}Mn, {sup 60}Co and {sup 137}Cs were leached out of the lysimeter. Leaching of {sup 60}Co and {sup 137}Cs decreased by factors of 10 and 7, respectively, in 3 years. Downward migration was the greatest in {sup 85}Sr. In the fourth year, radioactivity distributed rather uniformly over the top 15 cm layer of soil. The present results can be utilized for assessing the radiological impact and deciding counter-measures when the paddy field is contaminated with those radionuclides. (author). 13 refs., 2 tabs., 4 figs.

  5. Arsenic and other oxyanion-forming trace elements in an alluvial basin aquifer: Evaluating sources and mobilization by isotopic tracers (Sr, B, S, O, H, Ra)

    Energy Technology Data Exchange (ETDEWEB)

    Vinson, David S., E-mail: dsv3@duke.edu [Duke University, Division of Earth and Ocean Sciences, Box 90227, Durham, NC 27708 (United States); McIntosh, Jennifer C. [University of Arizona, Department of Hydrology and Water Resources, 1133 E. James E. Rogers Way, Tucson, AZ 85721 (United States); Dwyer, Gary S.; Vengosh, Avner [Duke University, Division of Earth and Ocean Sciences, Box 90227, Durham, NC 27708 (United States)

    2011-08-15

    oxyanion-forming trace element concentrations (B, V, Cr, Se, Mo, Sb), and F{sup -} concentrations are associated with a group of waters exhibiting lower {sup 87}Sr/{sup 86}Sr ratios (0.71012-0.71503), suggesting that sediments derived from Tertiary felsic volcanic rocks are a significant source of these trace elements in groundwater. {delta}{sup 34}S{sub SO4} (2.0-13.4 per mille) and {delta}{sup 11}B (-6.7 per mille to 18.2 per mille) variations suggest that rain-derived B and SO{sub 4}{sup 2-} plus marine gypsum derived from Paleozoic sedimentary rocks and B derived from felsic volcanic rocks explain the observed values. In addition to the sources of these elemental and isotopic signatures, down-gradient hydrogeochemical modification associated with silicate weathering and perhaps cation exchange are recorded by the decreasing Ca/Na ratio. Very low levels of {sup 226}Ra in groundwater relative to U throughout the basin-fill aquifer are consistent with the oxic, neutral to high-pH conditions in which mobility of U is strongly favored relative to Ra. Used in combination, multiple isotopic and geochemical tracers can provide valuable information for understanding the relative importance of sediment source and hydrogeochemical processes for observed levels of As and other naturally-occurring trace elements. These tracers, in particular {sup 87}Sr/{sup 86}Sr with its sensitivity to aquifer sediment source, can be applied to other alluvial basin-fill aquifers in the southwestern USA where multiple sediment types contribute varying amounts of As and other oxyanion-forming trace elements to groundwater.

  6. Investidura como doctor honoris causa por la Universidad de Castilla-La Mancha del Excmo. Sr. D. Eugenio Raúl Zaffaroni

    OpenAIRE

    Zaffaroni, Eugenio Raúl

    2004-01-01

    ÍNDICE: - Laudatio, a cargo del Prof. Dr. D. José Ramón Serrano-Piedecasas, Catedrático de Derecho penal. - "El Derecho penal liberal y sus enemigos", lección magistral a cargo del Prof. Dr. D. Eugenio Raúl Zaffaroni, Catedrático de Derecho penal y Criminología. - Discurso del Excmo. Sr. Rector Mgfco. de la Universidad de Castilla-La Mancha, Prof. Dr. D. Ernesto Martínez Ataz, Catedrático de Química Física.

  7. METHOD FOR SIMULTANEOUS 90SR AND 137CS IN-VIVO MEASUREMENTS OF SMALL ANIMALS AND OTHER ENVIRONMENTAL MEDIA DEVELOPED FOR THE CONDITIONS OF THE CHERNOBYL EXCLUSION ZONE

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.; Jannik, T.

    2011-10-01

    To perform in vivo simultaneous measurements of the {sup 90}Sr and {sup 137}Cs content in the bodies of animals living in the Chernobyl Exclusion Zone (ChEZ), an appropriate method and equipment were developed and installed in a mobile gamma beta spectrometry laboratory. This technique was designed for animals of relatively small sizes (up to 50 g). The {sup 90}Sr content is measured by a beta spectrometer with a 0.1 mm thick scintillation plastic detector. The spectrum processing takes into account the fact that the measured object is 'thick-layered' and contains a comparable quantity of {sup 137}Cs, which is a characteristic condition of the ChEZ. The {sup 137}Cs content is measured by a NaI scintillation detector that is part of the combined gamma beta spectrometry system. For environmental research performed in the ChEZ, the advantages of this method and equipment (rapid measurements, capability to measure live animals directly in their habitat, and the capability of simultaneous {sup 90}Sr and {sup 137}Cs measurements) far outweigh the existing limitations (considerations must be made for background radiation and the animal size, skeletal shape and body mass). The accuracy of these in vivo measurements is shown to be consistent with standard spectrometric and radiochemical methods. Apart from the in vivo measurements, the proposed methodology, after a very simple upgrade that is also described in the article, works even more accurately with samples of other media, such as soil and plants.

  8. Method for simultaneous 90Sr and 137Cs in-vivo measurements of small animals and other environmental media developed for the conditions of the Chernobyl exclusion zone.

    Science.gov (United States)

    Bondarkov, Mikhail D; Maksimenko, Andrey M; Gaschak, Sergey P; Zheltonozhsky, Viktor A; Jannik, G Timothy; Farfán, Eduardo B

    2011-10-01

    To perform in vivo simultaneous measurements of the 90Sr and 137Cs content in the bodies of animals living in the Chernobyl Exclusion Zone (ChEZ), an appropriate method and equipment were developed and installed in a mobile gamma beta spectrometry laboratory. This technique was designed for animals of relatively small sizes (up to 50 g). The 90Sr content is measured by a beta spectrometer with a 0.1-mm-thick scintillation plastic detector. The spectrum processing takes into account the fact that the measured object is "thick-layered" and contains a comparable quantity of 137Cs, which is a characteristic condition of the ChEZ. The 137Cs content is measured by a NaI scintillation detector that is part of the combined gamma beta spectrometry system. For environmental research performed in the ChEZ, the advantages of this method and equipment (rapid measurements, capability to measure live animals directly in their habitat, and the capability of simultaneous 90Sr and 137Cs measurements) far outweigh the existing limitations (considerations must be made for background radiation and the animal size, skeletal shape, and body mass). The accuracy of these in vivo measurements is shown to be consistent with standard spectrometric and radiochemical methods. Apart from the in vivo measurements, the proposed methodology, after a very simple upgrade that is also described in this paper, works even more accurately with samples of other media, such as soil and plants.

  9. Determination of concentration factors for Cs-137 and Ra-226 in the mullet species Chelon labrosus (Mugilidae) from the South Adriatic Sea.

    Science.gov (United States)

    Antovic, Ivanka; Antovic, Nevenka M

    2011-07-01

    Concentration factors for Cs-137 and Ra-226 transfer from seawater, and dried sediment or mud with detritus, have been determined for whole, fresh weight, Chelon labrosus individuals and selected organs. Cesium was detected in 5 of 22 fish individuals, and its activity ranged from 1.0 to 1.6 Bq kg(-1). Radium was detected in all fish, and ranged from 0.4 to 2.1 Bq kg(-1), with an arithmetic mean of 1.0 Bq kg(-1). In regards to fish organs, cesium activity concentration was highest in muscles (maximum - 3.7 Bq kg(-1)), while radium was highest in skeletons (maximum - 25 Bq kg(-1)). Among cesium concentration factors, those for muscles were the highest (from seawater - an average of 47, from sediment - an average of 3.3, from mud with detritus - an average of 0.8). Radium concentration factors were the highest for skeleton (from seawater - an average of 130, from sediment - an average of 1.8, from mud with detritus - an average of 1.5). Additionally, annual intake of cesium and radium by human adults consuming muscles of this fish species has been estimated to provide, in aggregate, an effective dose of about 4.1 μSv y(-1).

  10. Alkaline-alkaline earth fluoride carbonate crystals ABCO3F (A = K, Rb, Cs; B = Ca, Sr, Ba) as nonlinear optical materials.

    Science.gov (United States)

    Zou, Guohong; Ye, Ning; Huang, Ling; Lin, Xinsong

    2011-12-14

    A new series of alkaline-alkaline earth fluoride carbonates (KSrCO(3)F, RbSrCO(3)F, KCaCO(3)F, RbCaCO(3)F, CsCaCO(3)F, and Cs(3)Ba(4)(CO(3))(3)F(5)) were synthesized by spontaneous crystallization with molten fluxes. Their crystal structures, except for Cs(3)Ba(4)(CO(3))(3)F(5), exhibit the stacking of [AF](∞) (A = K, Rb, Cs) and [B(CO(3))](∞) (B = Ca, Sr) layers, and the coplanar alignment of [CO(3)] triangles. The results from the UV-vis diffuse reflectance spectroscopy study of the powder samples indicated that the short-wavelength absorption edges were all below 200 nm, except for Cs(3)Ba(4)(CO(3))(3)F(5), which is about 210 nm. Second-harmonic generation (SHG) on polycrystalline samples was measured using the Kurtz and Perry technique, which indicated that these carbonates are all phase-matchable materials in both visible and the UV region, and their measured SHG coefficients were about 3.33, 3.33, 3.61, 1.11, 1.11, and 1.20 times as large as that of d(36) (KDP), respectively. © 2011 American Chemical Society

  11. Measurements of grain-boundary inventories of {sup 137}Cs, {sup 90}Sr and {sup 99}Tc in used CANDU fuel

    Energy Technology Data Exchange (ETDEWEB)

    Stroes-Gascoyne, S.; Tait, J.C.; Porth, R.J.; McConnell, J.L.; Barnsdale, T.R.; Watson, S. [Whiteshell Labs., Pinawa, Manitoba (Canada)

    1993-12-31

    Two methods were used to measure grain-boundary inventories of {sup 137}Cs, {sup 90}Sr and {sup 99}Tc in used CANDU fuel, to corroborate source term estimates based on a fission gas release code. Used fuels were partially oxidized at 200{degrees}C in air to overall compositions of UO{sub 2+x} (0.15{<=} {times} {<=}0.25) to expose UO{sub 2} grain boundaries, followed by leaching in aqueous solution. Only a fraction (2 to 18%) of the calculated gap + grain-boundary inventories for {sup 137}Cs was released. This suggests that the calculations overestimate Cs release or that oxidation does not expose all grain boundaries, or that Cs release from grain boundaries is slow. Release of {sup 90}Sr (0.01 to 0.7%) agreed reasonably well with the source term estimates (0.001 to 0.3%). Release of {sup 99}Tc (0.3 to 1.5%) suggests that the source term estimate for the upper involved leaching of crushed and side-fractionated used fuel in either a static or dynamic system. A direct one-to-one correlation between calculated and measured gap + grain-boundary inventories for {sup 137}Cs was found for low- and medium-power fuels.

  12. Retention of simulated fallout nuclides in agricultural crops. 2. Deposition of Cs and Sr on grain crops

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, Aake; Rosen, K.; Haak, E

    1998-12-31

    Experiments with artificial wet depositions of {sup 134}Cs and {sup 85}Sr at different times during the growth period were carried out. The studies are complementary to the experiences after the Chernobyl fallout and the results are compared with similar earlier Swedish works on nuclide retention in experiments and on fallout in agriculture. The aim has been to cover the nuclide transfer to grain crops after deposition at different times during the growing period. The initial interception capacity per kg d.w., TRd, seemed to depend on the surface/weight ratio of the plant parts considered. Changes in TRd-values were rapid during the early growth but slower in later stages. The reduction half-time was then often 2 weeks for vegetative parts. Considering the fraction of a deposition retained, FRd, the residence half-time had an average length of 3-4 weeks. During that time there were possibilities for cesium penetration into the plant and further transfer to ears and grain. Strontium did not seem to be transferred that way. There was no increase of cesium in the ears per unit d.w. after the initial interception. However, there was a steady increase in the total content, especially after deposition during the latter half of the growth period when about 5 % was retained of cesium, and 2 % of strontium. The retention of fallout caesium in 1964 was statistically estimated to be of about the same size in Swedish grains 12 refs, 19 figs, 19 tabs

  13. Determination of Sr{sup 90}, Sb{sup 125}, Cs{sup 137} and absolute beta activities in First Cycle Supernatent

    Energy Technology Data Exchange (ETDEWEB)

    Helmholz, H.R.

    1954-03-15

    This report discusses procedures have been established for determining the absolute activities of Sr{sup 90}, Sb{sup 125}, Cs{sup 137}, and gross beta in First Cycle Supernatant. These procedures are also valid for other samples such as scavenged Radioactive Waste (RAW), the primary restriction being that the age of the material be at least 250 days so that any Sr{sup 89} activity (53 day half-life) is negligible. With the exception of the gross beta analysis the results are believed to be accurate to within 10%.

  14. Separation of Sr from Ca, Ba and Ra by means of Ca(OH)2 and Ba(Ra)Cl2 or Ba(Ra)SO4 for the determination of radiostrontium

    DEFF Research Database (Denmark)

    Chen, Q.J.; Hou, Xiaolin; Yu, Y.X.

    2002-01-01

    be completed. The new separation procedure has been successfully used for the determination of Sr-90 in samples with high Ca content, such as 451 of seawater and 2001 of drinking water. The analytical quality of the results is comparable to that of the traditional method using fuming nitric acid and BaCrO4...

  15. Spallation reaction study for fission products in nuclear waste: Cross section measurements for 137Cs and 90Sr on proton and deuteron

    Directory of Open Access Journals (Sweden)

    H. Wang

    2016-03-01

    Full Text Available We have studied spallation reactions for the fission products 137Cs and 90Sr for the purpose of nuclear waste transmutation. The spallation cross sections on the proton and deuteron were obtained in inverse kinematics for the first time using secondary beams of 137Cs and 90Sr at 185 MeV/nucleon at the RIKEN Radioactive Isotope Beam Factory. The target dependence has been investigated systematically, and the cross-section differences between the proton and deuteron are found to be larger for lighter spallation products. The experimental data are compared with the PHITS calculation, which includes cascade and evaporation processes. Our results suggest that both proton- and deuteron-induced spallation reactions are promising mechanisms for the transmutation of radioactive fission products.

  16. Spallation reaction study for fission products in nuclear waste: Cross section measurements for {sup 137}Cs and {sup 90}Sr on proton and deuteron

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H., E-mail: wanghe@ribf.riken.jp [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Otsu, H.; Sakurai, H.; Ahn, D.S. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Aikawa, M. [Faculty of Science, Hokkaido University, Sapporo 060-0810 (Japan); Doornenbal, P.; Fukuda, N.; Isobe, T. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Kawakami, S. [Department of Applied Physics, University of Miyazaki, Miyazaki 889-2192 (Japan); Koyama, S. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Kubo, T.; Kubono, S.; Lorusso, G. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Maeda, Y. [Department of Applied Physics, University of Miyazaki, Miyazaki 889-2192 (Japan); Makinaga, A. [Graduate School of Medicine, Hokkaido University, North-14, West-5, Kita-ku, Sapporo 060-8648 (Japan); Momiyama, S. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Nakano, K. [Department of Advanced Energy Engineering Science, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Niikura, M. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Shiga, Y. [Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo 171-8501 (Japan); RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Söderström, P.-A. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); and others

    2016-03-10

    We have studied spallation reactions for the fission products {sup 137}Cs and {sup 90}Sr for the purpose of nuclear waste transmutation. The spallation cross sections on the proton and deuteron were obtained in inverse kinematics for the first time using secondary beams of {sup 137}Cs and {sup 90}Sr at 185 MeV/nucleon at the RIKEN Radioactive Isotope Beam Factory. The target dependence has been investigated systematically, and the cross-section differences between the proton and deuteron are found to be larger for lighter spallation products. The experimental data are compared with the PHITS calculation, which includes cascade and evaporation processes. Our results suggest that both proton- and deuteron-induced spallation reactions are promising mechanisms for the transmutation of radioactive fission products.

  17. Spallation reaction study for fission products in nuclear waste: Cross section measurements for 137Cs and 90Sr on proton and deuteron

    Science.gov (United States)

    Wang, H.; Otsu, H.; Sakurai, H.; Ahn, D. S.; Aikawa, M.; Doornenbal, P.; Fukuda, N.; Isobe, T.; Kawakami, S.; Koyama, S.; Kubo, T.; Kubono, S.; Lorusso, G.; Maeda, Y.; Makinaga, A.; Momiyama, S.; Nakano, K.; Niikura, M.; Shiga, Y.; Söderström, P.-A.; Suzuki, H.; Takeda, H.; Takeuchi, S.; Taniuchi, R.; Watanabe, Ya.; Watanabe, Yu.; Yamasaki, H.; Yoshida, K.

    2016-03-01

    We have studied spallation reactions for the fission products 137Cs and 90Sr for the purpose of nuclear waste transmutation. The spallation cross sections on the proton and deuteron were obtained in inverse kinematics for the first time using secondary beams of 137Cs and 90Sr at 185 MeV/nucleon at the RIKEN Radioactive Isotope Beam Factory. The target dependence has been investigated systematically, and the cross-section differences between the proton and deuteron are found to be larger for lighter spallation products. The experimental data are compared with the PHITS calculation, which includes cascade and evaporation processes. Our results suggest that both proton- and deuteron-induced spallation reactions are promising mechanisms for the transmutation of radioactive fission products.

  18. Isotopic evidence for the retention of Sr-90 inferred from excess Zr-90 in the Oklo natural fission reactors: Implication for geochemical behaviour of fissiogenic Rb, Sr, Cs and Ba

    Science.gov (United States)

    Hidaka, Hiroshi; Sugiyama, Takeshi; Ebihara, Mitsuru; Holliger, Philippe

    1994-03-01

    In order to investigate the mobility of fissiogenic Sr-90 in the geological environment, the Zr isotopic compositions of seven samples from one of the newly formed Oklo natural reactor zones (i.e., reactor core and adjacent rocks (10, SF84)) in the Republic of Gabon were determined with an inductively coupled plasma mass spectrometer (ICP-MS). Zr isotopes in uraninite grains from different reactor zones were also measured by secondary ion mass spectrometry (SIMS). Fissiogenic Zr isotopic abundances of three samples from the reactor core have excess Zr-90, which has never before been formed in previous Oklo samples. In this paper, the geochemical behaviour of Zr-90 is discussed by making use of the relative retentivity inferred from the isotopic abundance of Sr. The excess in Zr-90 suggests dependence on the degree of retention/migration of Sr-90, the precursor of Zr-90 in the fission chain. In the aqueous phase, chemical fractionation between Sr and Zr could have occurred before radioactive Sr-90 decayed. Considering the halflife of Sr-90 (t(sub 1/2) = 29.1 y), considerable amounts of the latter have been produced during criticality. Sr and Zr (including Zr-90) could have been redistributed between the reactor core and its vicinity. The retentivity of fissiogenic Zr-90 in reactor core 10 is not homogeneous. In addition, the distributions of Rb, Cs and Ba is also heterogeneous.

  19. First-principles study of new series of quaternary Heusler alloys CsSrCZ (Z=Si, Ge, Sn, P, As, and Sb)

    Energy Technology Data Exchange (ETDEWEB)

    Bouabça, A. [Condensed Matter and Sustainable Development Laboratory (LMCDD), University of Sidi Bel-Abbes, Sidi Bel-Abbes 22000 (Algeria); Rozale, H., E-mail: hrozale@yahoo.fr [Condensed Matter and Sustainable Development Laboratory (LMCDD), University of Sidi Bel-Abbes, Sidi Bel-Abbes 22000 (Algeria); Amar, A. [Condensed Matter and Sustainable Development Laboratory (LMCDD), University of Sidi Bel-Abbes, Sidi Bel-Abbes 22000 (Algeria); Wang, X.T. [School of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 400044 (China); Sayade, A. [UCCS, CNRS-UMR 8181, Université d’Artois, Faculté des Sciences Jean Perrin, Rue Jean Souvraz, SP 18, 62307 Lens Cedex (France); Chahed, A. [Condensed Matter and Sustainable Development Laboratory (LMCDD), University of Sidi Bel-Abbes, Sidi Bel-Abbes 22000 (Algeria)

    2016-12-01

    The structural, electronic, magnetic, and thermal properties of new quaternary Heusler alloys CsSrCZ (Z=Si, Ge, Sn, P, As, and Sb) were investigated using the full-potential linearized augmented plane wave (FPLAPW) within the generalized gradient approximation (GGA) and GGA plus modified Becke and Johnson as the exchange correlation. The results showed that all Heusler compounds were stable in Type (I) structure. The CsSrCZ (Z=Si, Ge, Sn) compounds had a nearly HM characteristic, and CsSrCZ (Z=P, As, Sb) compounds were true half-metallic (HM) ferromagnets. The strong spin polarization of p orbital for C, Si, Ge, Sn, P, As, and Sb atoms is found to be the origin of ferromagnetic. The half-metallicity is preserved up to a lattice contraction of 3.45%, 1.69%, 1.69%, 7.16%, 7.16%, and 11.2% for all six quaternary Heusler compounds. We also investigated the thermal effects using the quasi-harmonic Debye model. - Highlights: • Electronic, magnetic, and thermodynamic properties of CsSrCZ (Z=Si, Ge, Sn, P, As, and Sb) are investigated. • Until now, there have been no reports theoretical and experimental studies on d{sup 0} half-metals with quaternary structures. • The strong spin polarization of p orbital for C, Si, Ge, Sn, P, As, and Sb atoms is found to be the origin of ferromagnetic. • The half-metallicity is preserved up to a lattice contraction.

  20. ASSESSMENT OF 90SR AND 137CS PENETRATION INTO REINFORCED CONCRETE (EXTENT OF 'DEEPENING') UNDER NATURAL ATMOSPHERIC CONDITIONS

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.; Jannik, T.

    2011-10-01

    When assessing the feasibility of remediation following the detonation of a radiological dispersion device or improvised nuclear device in a large city, several issues should be considered including the levels and characteristics of the radioactive contamination, the availability of resources required for decontamination, and the planned future use of the city's structures and buildings. Currently, little is known about radionuclide penetration into construction materials in an urban environment. Knowledge in this area would be useful when considering costs of a thorough decontamination of buildings, artificial structures, and roads in an affected urban environment. Pripyat, a city substantially contaminated by the Chernobyl Nuclear Power Plant accident in April 1986, may provide some answers. The main objective of this study was to assess the depth of {sup 90}Sr and {sup 137}Cs penetration into reinforced concrete structures in a highly contaminated urban environment under natural weather conditions. Thirteen reinforced concrete core samples were obtained from external surfaces of a contaminated building in Pripyat. The concrete cores were drilled to obtain sample layers of 0-5, 5-10, 10-15, 15-20, 20-30, 30-40, and 40-50 mm. Both {sup 90}Sr and {sup 137}Cs were detected in the entire 0-50 mm profile of the reinforced cores sampled. In most of the cores, over 90% of the total {sup 137}Cs inventory and 70% of the total {sup 90}Sr inventory was found in the first 0-5 mm layer of the reinforced concrete. {sup 90}Sr had penetrated markedly deeper into the reinforced concrete structures than {sup 137}Cs.

  1. FREQUENCY DISTRIBUTIONS OF 90SR AND 137CS CONCENTRATIONS IN AN ECOSYSTEM OF THE 'RED FOREST' AREA IN THE CHERNOBYL EXCLUSION ZONE

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.; Jannik, T.; Caldwell, E.

    2011-10-01

    In the most highly contaminated region of the Chernobyl Exclusion Zone: the 'Red Forest' site, the accumulation of the major dose-affecting radionuclides ({sup 90}Sr and {sup 137}Cs) within the components of an ecological system encompassing 3,000 m{sup 2} were characterized. The sampled components included soils (top 0-10 cm depth), Molina caerulea (blue moor grass), Camponotus vagus (carpenter ants) and Pelobates fuscus (spade-footed toad). In a comparison among the components of this ecosystem, the {sup 90}Sr and {sup 137}Cs concentrations measured in 40 separate grids exhibited significant differences, while the frequency distribution of the values were close to a logarithmically normal leptokurtic distribution with a significant right-side skew. While it is important to identify localized areas of high contamination or 'hot spots,' including these values in the arithmetic mean may overestimate the exposure risk. In component sample sets that exhibited logarithmically normal distribution, the geometrical mean more accurately characterizes a site. Ideally, risk assessment is most confidently achieved when the arithmetic and geometrical means are most similar, meaning the distribution approaches normal. Through bioaccumulation, the highest concentrations of {sup 90}Sr and {sup 137}Cs were measured in the blue moor grass and spade-footed toad. These components also possessed distribution parameters that shifted toward a normal distribution.

  2. [Prognosis of accumulation of 137Cs and 90Sr in the herbage of the main types of the Belarus Polessje meadows using agrochemical soil properties].

    Science.gov (United States)

    Podoliak, A G; Timofeev, S F; Grebenshchikova, N V; Arastovich, T V; Zhdanovich, V P

    2005-01-01

    On the basis of long-term stationary experience it was established that the minimum accumulation quantities for 137Cs and 90Sr in the herbage of the dry, lowland and flood-plain types of the Belarus Polessje meadows contaminated with Chemobyl radionuclides are determined when the optimum of basic agrochemical soil properties is achieved with application of the scientifically reasonable protective measures. For remote prognosis of radionuclide contents in natural and cultural meadow herbage the use of transfer factors (TFa, (Bq/kg)(kBq/m2)) based on the complex agrochemical parameters--agrochemical cultivation soil index (Icd) and basic saturation degree (V, %), which take into account some soil characteristics simultaneously, is a streamlined approach. This paper provides the equations of linear and multiple regressions, which can be used to calculate the transfer factors for 137Cs and 90Sr uptake and the herbage contamination degree for the main types of meadows of the region, that will allow reducing the volume of forage production (hay, green bulk), which is not adequate to established permissible levels: "Republican allowable levels of the contents of 137Cs and 90Sr in agricultural raw material and forages".

  3. Frequency distributions of 90Sr and 137Cs concentrations in an ecosystem of the "Red Forest" area in the Chernobyl exclusion zone.

    Science.gov (United States)

    Gaschak, Sergey P; Makliuk, Yulia A; Maksimenko, Andrey M; Bondarkov, Mikhail D; Chizhevsky, Igor; Caldwell, Eric F; Jannik, G Timothy; Farfán, Eduardo B

    2011-10-01

    In the most highly contaminated region of the Chernobyl Exclusion Zone, the "Red Forest" site, the accumulation of the major dose-affecting radionuclides (90Sr and 137Cs) within the components of an ecological system encompassing 3,000 m(2) was characterized. The sampled components included soils (top 0-10 cm depth), Molina caerulea (blue moor grass), Camponotus vagus (carpenter ants), and Pelobates fuscus (spade-footed toad). In a comparison among the components of this ecosystem, the 90Sr and 137Cs concentrations measured in 40 separate grids exhibited significant differences, while the frequency distribution of the values was close to a logarithmically-normal leptokurtic distribution with a significant right-side skew. While it is important to identify localized areas of high contamination or "hot spots," including these values in the arithmetic mean may overestimate the exposure risk. In component sample sets that exhibited logarithmically normal distribution, the geometric mean more accurately characterizes a site. Ideally, risk assessment is most confidently achieved when the arithmetic and geometric means are most similar, meaning the distribution approaches normal. Through bioaccumulation, the highest concentrations of 90Sr and 137Cs were measured in the blue moor grass and spade-footed toad. These components also possessed distribution parameters that shifted toward a normal distribution.

  4. First-principles study of new series of quaternary Heusler alloys CsSrCZ (Z=Si, Ge, Sn, P, As, and Sb)

    Science.gov (United States)

    Bouabça, A.; Rozale, H.; Amar, A.; Wang, X. T.; Sayade, A.; Chahed, A.

    2016-12-01

    The structural, electronic, magnetic, and thermal properties of new quaternary Heusler alloys CsSrCZ (Z=Si, Ge, Sn, P, As, and Sb) were investigated using the full-potential linearized augmented plane wave (FPLAPW) within the generalized gradient approximation (GGA) and GGA plus modified Becke and Johnson as the exchange correlation. The results showed that all Heusler compounds were stable in Type (I) structure. The CsSrCZ (Z=Si, Ge, Sn) compounds had a nearly HM characteristic, and CsSrCZ (Z=P, As, Sb) compounds were true half-metallic (HM) ferromagnets. The strong spin polarization of p orbital for C, Si, Ge, Sn, P, As, and Sb atoms is found to be the origin of ferromagnetic. The half-metallicity is preserved up to a lattice contraction of 3.45%, 1.69%, 1.69%, 7.16%, 7.16%, and 11.2% for all six quaternary Heusler compounds. We also investigated the thermal effects using the quasi-harmonic Debye model.

  5. Distribution of {sup 226} Ra, {sup 232} Th, {sup 40} K and {sup 137} Cs in soils of Province of Camaguey, Cuba

    Energy Technology Data Exchange (ETDEWEB)

    Flores, Osvaldo Brigido; Barreras Caballero, Aldo A.; Montalvan Estrada, Adelmo; Queipo Garcia, Maite [Ministerio da Ciencia, Tecnologia y Medio Ambiente, Camaguey (Cuba). Centro de Atencion a la Actividad Nuclear. Lab. de Vigilancia Radiologica Ambiental]. E-mail: sean@caonao.cmw.inf.cu; Zerquera, Juan Tomas [Centro de Proteccion y Higiene de las Radiaciones, La Habana (Cuba)

    2001-07-01

    A survey programme aimed at studying the environmental radioactivity in the Province of Camaguey in the eastern region of Cuba was undertaken. The average concentrations of {sup 226} Ra, {sup 232} Th, and {sup 40} K in the surveyed soils were 26.4, 11.5 and 210 Bq.kg{sup -1}, respectively. The man-made radionuclide found was {sup 137} Cs and its concentration was similar to those reported in regions affected only by global radioactive fallout, (7.9 Bq.kg{sup -1}). Radiological measurements carried out with a portable ionization chamber RSS-112 at the sampled sites revealed an average outdoor absorbed dose rate of 59.0 nGy.h{sup -1} due to cosmic rays and terrestrial gamma radiation. Computed dose rates obtained through the UNSCEAR(1993) dose coefficients range from 4-182 nGy.h{sup -1}, with a mean value of 27.8 nGy.h{sup -1}, due to natural terrestrial gamma radiation. Ratio of Indoor to Outdoor absorbed dose rates in air was 1.75. The average value of absorbed dose rate in air for the ionizing component of cosmic rays was 31.8 nGy.h{sup -1} at sea level. Because of the 95% of the Camaguey population lives at altitudes close to sea level (10-100 m), the absorbed dose rate in outdoor air from ionizing component of cosmic rays was estimated to be 32.3 nGy.h{sup -1}. An annual average effective dose equivalent of 510 {mu}Sv was estimated for Camaguey population due to the ionizing component of cosmic and gamma terrestrial radiation. This value is lower than the 760 {mu}Sv.year{sup -1} estimated as a world average by UNSCEAR (1993). (author)

  6. Vertical migration of {sup 60}Co, {sup 137}Cs and {sup 226}Ra in agricultural soils as observed in lysimeters under crop rotation

    Energy Technology Data Exchange (ETDEWEB)

    Shinonaga, T. [Division of Environmental and Life Science, ARC Seibersdorf Research, A-2444 Seibersdorf (Austria)]. E-mail: t.shinonaga@iaea.org; Schimmack, W. [Institute of Radiation Protection, GSF-National Research Center for Environment and Health, D-85764 Neuherberg (Germany); Gerzabek, M.H. [Division of Environmental and Life Science, ARC Seibersdorf Research, A-2444 Seibersdorf (Austria); Department for Forest and Soil Sciences, University of Natural Resources and Applied Life Science, Gregor-Mendel-Strasse 33, A-1180 Vienna (Austria)

    2005-07-01

    In most studies quantifying the migration parameters - apparent migration velocity and apparent dispersion coefficient - of radionuclides in the soil by model calculations, these parameters are determined for undisturbed soils. For soils disturbed by ploughing, however, no such data are available in the literature. Therefore, in the present study, the migration parameters of {sup 137}Cs, {sup 60}Co and {sup 226}Ra were estimated for ploughed soils by means of a convection-dispersion model. The depth distributions of the radionuclides were determined in four lysimeters (area: 1 m{sup 2}, depth of soil monolith: 0.75 m) filled with artificially contaminated soils of different types in July 1990. The lysimeters were cropped with agricultural plants. The soil in each lysimeter was ploughed manually once a year until 1996 (plough depth 20 cm). In July 1999, soil samples were collected from three pits in each lysimeter. The depth distributions of all radionuclides proved to be very similar in each soil pit. The spatial variability of the depth distributions of a given radionuclide within the lysimeters was about the same as their variability between the four lysimeters. Evaluation of the migration parameters revealed that the convective transport of the radionuclides was always rather small or even zero, while the dispersive transport caused a 'melting' process of the initially sharp activity edge at the lower border of the Ap horizon. These results are explained by the high evapotranspiration (80-90% of the total precipitation plus irrigation) and the small amounts of seepage water during the observation period of 9 years.

  7. Accumulation and distribution of (137)Cs and (90)Sr in the body of the wild boar (Sus scrofa) found on the territory with radioactive contamination.

    Science.gov (United States)

    Gulakov, Andrey Vladimirovich

    2014-01-01

    We studied the concentration and distribution of (137)Cs and (90)Sr in the bodies of 188 wild boar (Sus scrofa Linnaeus, 1758) taken near the Chernobyl site. Of these, 111 animals were taken in the Alienation Zone, 41 animals were taken in the Permanent Control Zone and 36 animals were taken in the Periodic Control Zone. The samples included muscle and bone (rib) tissues and samples of heart, liver, lungs, kidneys, spleen, genitals and skin. The weight of the samples was 0.5 kg fresh weigh. The average concentration of (137)Cs in the muscles of the wild boar found in the Alienation Zone was 46 ± 10 kBq/kg, in the Permanent Control Zone - 13 ± 3.0 kBq/kg and in the Periodic Control Zone - 0.6 ± 0.1 kBq/kg. The largest concentration of (137)Cs was detected in the muscle tissue and kidneys taken animals. In some samples of muscle tissue it reached more than 660 kBq/kg. The (137)Cs concentrations were also high in heart and spleen up 64.3 kBq/kg and 67.5 kBq/kg - animals from the Alienation Zone and 10.3-10.6 kBq/kg - animals from the Permanent Control zone. The lowest concentration of (137)Cs was found in the lungs and skin of animals. The analyses of (90)Sr concentration in the organs and tissues of the wild boar showed that (90)Sr was concentrated mainly in the bone tissue. The average level of (90)Sr concentration in bone was 17.6 kBq/kg fresh weight animals from the Alienation Zone and 13.47 kBg/kg - animals from the Permanent Control zone. In muscle tissues and organs contained (90)Sr - 30.0-110.0 Bq/kg in the Alienation Zone and 11.0-30.0 Bq/kg in the Permanent Control zone.

  8. Study on Adsorptive Property of XJ Bentonite for Strontium and Caesium%新疆膨润土对Sr~(2+)、Cs~+的吸附性能的研究

    Institute of Scientific and Technical Information of China (English)

    李宁波; 易发成

    2009-01-01

    An intermittence method was adopted to study the adsorption of XJ bentonite (XJ for short) for Sr~(2+) and Cs~+ under various conditions including different concentration, solid-to-liquid ratio ,temperature, pH value and groundwaters. The results show that adsorptive capacity of XJ for Sr~(2+) and Cs~(2+) is high with adsorptive equilibrium time of 7 days and equilibrium adsorptive quantities were 40mg/g and 129mg/g when Sr~(2+) and Cs~+concentrations are 0.01mol/L. Adsorptive capacity firstly depends on the solution concentration and solid-to-liquid ratio, secondly on the grotmdwatera, pH value and temperature of the solution.%采用间歇法研究在不同环境条下(浓度、固液比、温度、pH值、介质),新疆膨润土(简称XJ)对Sr~(2+)、Cs~+'的吸附性能影响.结果表明:XJ对Sr~(2+)、Cs~+的吸附性能比较好,当Sr~(2+)、Cs~+浓度为0.01mol/L时,XJ对Sr~(2+)、Cs~+的吸附平衡时间约在7天左右,平衡吸附量分别为40mg/g、129mg/g.Sr~(2+)、Cs~+的浓度和不同固液比对XJ的吸附性能影响比较大,其次是不同介质、溶液的pH值和溶液的温度.

  9. Transfer of alkaline earth elements in mothers' milk and doses from {sup 45}Ca, {sup 90}Sr and {sup 226}Ra

    Energy Technology Data Exchange (ETDEWEB)

    Smith, T.J.; Phipps, A.W.; Fell, T.P.; Harrison, J.D

    2003-07-01

    An international programme of work is currently under way to develop methods for calculating doses to infants from ingestion of radionuclides present in mothers' milk. This paper considers the special case of the alkaline earth elements. Models have been developed for {sup 45}Ca, {sup 90}Sr and {sup 226}Ra and the sensitivity of results to various changes in parameter values is discussed. A complication when calculating doses from intakes of radium is that the International Commission on Radiological Protection has previously recommended that doses from decay products of radium should be calculated using element-specific biokinetic models (so-called independent biokinetics). An extension of this method to the models for breastfeeding is proposed. Preliminary estimates of the doses received by the infant for a number of maternal intake scenarios show that doses to the infant can exceed the corresponding adult dose, such as for {sup 45}Ca (ratio = 3.1) while, in other cases such as {sup 90}Sr, the infant dose can be a significant fraction of the adult dose. (author)

  10. Uptake and Distribution of 133 Cs and 88 Sr in sunflower(Helianthus annuus L.)%向日葵(Helianthus annuus L.)对133 Cs、88 Sr的吸收和分布

    Institute of Scientific and Technical Information of China (English)

    闻方平; 王丹; 徐长合; 徐凤亭; 张志伟; 张晓雪

    2009-01-01

    在向日葵体内的分布与目前对放射性137 Cs和90 Sr的研究结果相似,所以133Cs和88Sr可分别预测137 Cs和90 Sr的运转.向日葵是治理大面积低放核素污染土壤的较佳植物种类.%Sr.133 Cs and 88Sr could be useful to understand and predict the long-term movements of 137 Cs and 90 Sr,respectively.Sunflower is the acceptable plants for phytoremediation to the low-level radioactive soil.

  11. Concentration in activity of {sup 137} Cs, {sup 40} K, {sup 232} Th, {sup 226} Ra in waste deposits of the benefits of minerals in the State of Zacatecas; Concentracion en actividad de {sup 137} Cs, {sup 40} K, {sup 232} Th, {sup 226} Ra en depositos de desecho del beneficio de minerales en el Estado de Zacatecas

    Energy Technology Data Exchange (ETDEWEB)

    Leal, B.; Mireles, F.; Quirino, L.; Davila, I.; Ramirez, F. [UAZ, A.P. 579C, 98068 Zacatecas (Mexico)

    2003-07-01

    The necessity to report the changes in the contained radionuclides in the terrestrial crust, or those deposited by the atomic tests around the world, becomes clear when observing the use of material of waste of those mines. With the purpose of quantifying the concentration in activity its were meet a series of waste samples in mines of the municipalities of Zacatecas, Fresnillo, Guadalupe and Veta Grande of the state of Zacatecas, Mexico. The analysis was carried out by gamma spectrometry with a HPGe detector with a resolution of 1.9 keV corresponding to an energy of 1.33 MeV calibrated in efficiency and energy by means of a certified standard multi nuclide in activity with identical geometry to that of the samples. The times of count are of 80000 seconds, with the purpose of to reduce the relative uncertainties and to define well the interest regions. The activity of {sup 226} Ra and {sup 232} Th is obtained through the one {sup 214} Bi and {sup 228} Ac respectively, the concentration was also measured in activity of the one {sup 40} K and the {sup 137} Cs in units of Bq kg{sup -1}. (Author)

  12. Observed half-lives of {sup 3}H, {sup 90}Sr and {sup 137}Cs in hydrosphere in the Vltava River basin and impact of NPP Temelin (Bohemia)

    Energy Technology Data Exchange (ETDEWEB)

    Hanslik, E.J.; Ivanovova, D.; Sedlarova, B.; Simonek, P. [T. G. Masaryk Water Research Institute, Prague (Czech Republic); Krizova-Jedinakova, V. [Institute of Chemical Technology, Technicka 6, Prague (Czech Republic)

    2004-07-01

    Observation of reference conditions on the Upper Vltava River in the period before construction of Temel Nuclear Power Plant (NPP) was focused on examination of concentrations of artificial radionuclides {sup 3}H, {sup 90}Sr and {sup 137}Cs in components of the hydrosphere. Concentrations of these radionuclides were observed in water from tributaries to Orl Reservoir, which will be a receiving water body of waste waters from the NPP, and also in the water at outflow from the reservoir. Concentrations of radionuclides {sup 90}Sr, {sup 137}Cs and {sup 134}Cs were examined in samples of sediments, biomass of aquatic flora and fish species. Concentrations of {sup 3}H were also analysed in samples of precipitation water collected at three stations located in the vicinity of the NPP. For ensuring complete information, the observation of the radionuclides included also resources of drinking water and sludge from water treatment plants sited close to the NPP [1]. The observation has been continued [2]. The tritium concentrations were determined by using LSC method on Quantulus device, gamma spectrometric method on Canberra device was used for {sup 137}Cs and {sup 134}Cs, and {sup 90}Sr was determined by a standard method after radiochemical separation like {sup 90}Y. The results of the observation were used for derivation of decreasing trends in the concentrations of the radionuclides. It was demonstrated that kinetic equation of the 1. order can provide good description of the process. Concentrations of {sup 137}Cs in surface water exhibited two phases of decrease. The first one, which lasted until 1994, was faster. The observed half-life values were in the range between 1.1 and 2.2 years. The half-life values during the slower second phase, which began in 1995, are between 8.6 and 32.2 years. Concentrations of {sup 90}Sr in the water were monotonously decreasing with half-lives of 6.8 years in the period 1963 - 1968 and 6.7 years in the period 1993 - 2001. Gradient of a

  13. Spallation reaction study for fission products in nuclear waste: Cross section measurements for 137Cs, 90Sr and 107Pd on proton and deuteron

    Directory of Open Access Journals (Sweden)

    Wang He

    2017-01-01

    Full Text Available Spallation reactions for the long-lived fission products 137Cs, 90Sr and 107Pd have been studied for the purpose of nuclear waste transmutation. The cross sections on the proton- and deuteron-induced spallation were obtained in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. Both the target and energy dependences of cross sections have been investigated systematically. and the cross-section differences between the proton and deuteron are found to be larger for lighter fragments. The experimental data are compared with the SPACS semi-empirical parameterization and the PHITS calculations including both the intra-nuclear cascade and evaporation processes.

  14. Physico-chemical characterisation and sorption measurements of Cs, Sr, Ni, Eu, Th, Sn and Se on Opalinus clay from Mont Terri

    Energy Technology Data Exchange (ETDEWEB)

    Lauber, Matthias; Baeyens, Bart; Bradbury, Michael H

    2000-12-01

    Opalinus Clay is currently under investigation as a potential host rock for the disposal of high level and long-lived intermediate radioactive waste. A throughout physico-chemical characterisation was carried out on a bore core sample from the underground rock laboratory Mont Terri (Canton Jura). The results of these investigations indicate that the major characteristics (mineralogy, cation exchange capacity, cation occupancies, selectivity coefficients, chloride and sulphate inventories) were very similar to a different core sample, previously used for pore water modelling studies. It was concluded that the pore water compositions derived in the earlier studies were reliable and could be used in this work. The organic matter which dissolved from the Opalinus Clay rock was not humic or fulvic acids and the concentration remaining in the liquid phase in the sorption experiments was < 0.5 ppm C. The organic matter is therefore considered to have little or no influence on the sorption behaviour of the studied radionuclides. Redox potential measurements of the Opalinus Clay/synthetic pore water system inside the glove boxes indicated anoxic conditions. The main focus of the experimental work presented here is on the sorption behaviour of Cs (I), Sr (II), Ni (II), Eu (III), Th (IV), Sn (IV) and Se (IV) on Opalinus Clay equilibrated with synthetic pore waters at pH 6.3 and 8. Sorption isotherms were measured for Cs, Ni, Eu, Th and Se. Single point data were measured for Sr and Sn. For all radionuclides studied the sorption kinetics were measured first. The times required to complete the sorption on the Opalinus Clay varied between one day for Th and one month for Ni and Se. Within the concentration ranges under study the uptake of Cs, Ni, Eu and Se on Opalinus Clay was non-linear, whereas for Th a linear sorption behaviour was observed. For Ni, Eu and Th the sorption increased with increasing pH. For Cs a pH independent sorption behaviour was observed. The concentration

  15. Fluorophores as Chemosensors for Sr(sup 2+) and Cs(sup +) Based on Calix[4]arenes and Coumarin Reporter Groups

    Energy Technology Data Exchange (ETDEWEB)

    Gorestzki, Gudrun; Brown, Gilbert M.; Bonnesen, Peter V.

    2003-09-10

    Fluorescent sensors are being developed for Cs + and Sr2+ which combine a molecular recognition element with an optical transduction element. Such sensors will be needed for real-time application in the characterization of nuclear waste and waste process streams. The fluorescent method is very important due to its high sensitivity and direct visual perception even in highly dilute solutions and its potential for remote application utilizing fiber optics. Crown ether bridged calix[4]arenes have been widely used as a three-dimensional platform for selective metal ion recognition. Coumarins show interesting photochemical and photophysical properties and are widely used in laser dye applications. These fluorescence probes increase their dipolar moment when excited. We will report the synthesis of calix[4]arene-crown-6 derivatives possessing 1,3-alternate conformation and incorporating a coumarin based fluorescence reporter group. Selectivity for Sr2+ over Cs + is obtained by using azacrowns and the sensitivity will be determined by varying the donor atom set as well as the substitution pattern of the coumarin.

  16. Removal of Cs{sup +}, Sr{sup 2+}, and Co{sup 2+} ions from the mixture of organics and suspended solids aqueous solutions by zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Xiang Hong; Fang, Fang; Lu, Chun Hai [College of Nuclear Technology and Automation Engineering, Chengdu University of Technology, Chengdu (China); Zheng, Lei [Southwest University of Science and Technology, Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, Mianyang (China)

    2017-04-15

    Serving as an excellent adsorbent and inorganic ion exchanger in the water purification field, zeolite 4A has in this work presented a strong capability for purifying radioactive waste, such as Sr{sup 2+}, Cs{sup +}, and Co{sup 2+} in water. During the processes of decontamination and decommissioning of suspended solids and organics in low-level radioactive wastewater, the purification performance of zeolite 4A has been studied. Under ambient temperature and neutral condition, zeolite 4A absorbed simulated radionuclides such as Sr{sup 2+}, Cs{sup +}, and Co{sup 2+} with an absorption rate of almost 90%. Additionally, in alkaline condition, the adsorption percentage even approached 98.7%. After conducting research on suspended solids and organics of zeolite 4A for the treatment of radionuclides, it was found that the suspended clay was conducive to absorption, whereas the absorption of organics in solution was determined by the species of radionuclides and organics. Therefore, zeolite 4A has considerable potential in the treatment of radioactive wastewater.

  17. Effects of {sup 137}Cs and {sup 90}Sr on structure and functional aspects of the microflora in agricultural used soils

    Energy Technology Data Exchange (ETDEWEB)

    Niedree, Bastian

    2013-11-01

    At long sight {sup 137}Cs and {sup 90}Sr are the main radionuclides responsible for the contamination of agricultural soils due to core melts in nuclear power plants such as Chernobyl or Fukushima. Once deposited on the soil surface, the two radionuclides remain in the upper soil layer for several decades. In the upper soil layer the highest microbial activity can be found, due to high organic matter contents, warm temperatures and gas exchange with the atmosphere. Hence, in contaminated soils microorganisms in upper soil layers (e.g. the plow layer on agricultural fields) are exceedingly exposed to radioactivity. However, no data are available how radioactive contaminations with {sup 137}Cs or {sup 90}Sr in a realistic order of magnitude affect the microbial community and its functions in soils. This dissertation discusses the effects of radioactive contaminations on the microbial community structure and some of its functions in soils. Therefore, typical agricultural soils, an Orthic Luvisol from field site Merzenhausen and a Gleyic Cambisol from field site Kaldenkirchen-Huelst were artificially contaminated with various concentrations of {sup 137}Cs and {sup 90}Sr and partly applied with radiolabeled substrates and incubated in soil microcosms under controlled laboratory conditions. The lower radionuclide concentrations corresponded to the contaminations in the Chernobyl exclusion zone, the higher concentrations were up to 50-fold that of the maximum occurring hotspots ({sup 137}Cs) in this zone. In three experiments the effects of the ionizing radiation on the bacterial and the fungal community structure (16S and 18S rDNA DGGE), the degradation of {sup 14}C-labeled wheat straw or uniformly ring-labeled 2,4-dichlorophenoxyacetic acid, the development of the fungal biomass (ergosterol quantification) and the chemical composition of the soil organic matter ({sup 13}C CP/MAS NMR) were investigated. In half of the microcosms the soils were autoclaved and reinoculated

  18. [Prognosis of dynamics and risk of exceeding permissible levels of 137Cs and 90Sr contents in fish in the Kiev Reservoir at the late phase of the Chernobyl accident].

    Science.gov (United States)

    2013-01-01

    On the basis of the radionuclide specific activity measurements made on 832 samples of fish in 2009-2011 and taking into account literature data, the parameters of the stochastic model have been derived to describe the 137Cs and 90Sr contents in typical commercial fish species in the Kiev Reservoir at the late phase of the Chernobyl accident, including: statistical variability, seasonal changes and monotonous long-term trends. At any fixed moment of the year the standard deviations of logarithms of the 137Cs and 90Sr specific activities in carnivorous and benthophage fish species do not reliably differ, making up at average 0.4. The maximum vari- ation of the 137Cs specific activity (a four-fold decrease from April to November) was observed in pike. The obtained values of the ecological half-life periods for 137Cs and 90Sr (1.3-14 years) in fish of the Kiev reservoir in 2002-2012 were significantly lower than both the radioactive decay periods and the estimates of the IAEA Chernobyl Forum. Based on the obtained model parameters, the dynamics of the 137Cs and 90Sr specific ac- tivities in main commercial fish of the Kiev reservoir has been described and the risk of exceeding the permis- sible levels of these radionuclides in fish at the late phase of the Chernobyl accident has been estimated. Now the risk of catching fish with the specific activities of 137Cs and 90Sr above the permissible levels (150 Bq/kg and 35 Bq/kg, respectively) does not exceed 10% (except perch in the spring spawning period that is banned for fishing in Ukraine). Corresponding risks for roach, white bream and rudd are less than 0.1%.

  19. Impact of Scots pine (Pinus sylvestris L.) plantings on long term {sup 137}Cs and {sup 90}Sr recycling from a waste burial site in the Chernobyl Red Forest

    Energy Technology Data Exchange (ETDEWEB)

    Thiry, Yves, E-mail: Yves.Thiry@andra.f [SCK-CEN, Belgian Nuclear Research Center, Foundation of Public Utility, Boeretang 200, 2400 Mol (Belgium); Colle, Claude [IRSN, Institute for Radioprotection and Nuclear Safety, Ce Cadarache, 13115 Saint Paul-lez-Durance Cedex (France); Yoschenko, Vasyl; Levchuk, Svjatoslav [UIAR, Ukrainian Institute of Agricultural Radiology, Mashinostroiteley Str.7, Kiev Region, 08162 Chabany (Ukraine); Van Hees, May [SCK-CEN, Belgian Nuclear Research Center, Foundation of Public Utility, Boeretang 200, 2400 Mol (Belgium); Hurtevent, Pierre [IRSN, Institute for Radioprotection and Nuclear Safety, Ce Cadarache, 13115 Saint Paul-lez-Durance Cedex (France); Kashparov, Valery [UIAR, Ukrainian Institute of Agricultural Radiology, Mashinostroiteley Str.7, Kiev Region, 08162 Chabany (Ukraine)

    2009-12-15

    Plantings of Scots pine (Pinus sylvestris L.) on a waste burial site in the Chernobyl Red Forest was shown to greatly influence the long term redistribution of radioactivity contained in sub-surfaces trenches. After 15 years of growth, aboveground biomass of the average tree growing on waste trench no.22 had accumulated 1.7 times more {sup 137}Cs than that of trees growing off the trench, and 5.4 times more {sup 90}Sr. At the scale of the trench and according to an average tree density of 3300 trees/ha for the study zone, tree contamination would correspond to 0.024% of the {sup 137}Cs and 2.52% of the {sup 90}Sr contained in the buried waste material. A quantitative description of the radionuclide cycling showed a potential for trees to annually extract up to 0.82% of the {sup 90}Sr pool in the trench and 0.0038% of the {sup 137}Cs. A preferential {sup 90}Sr uptake from the deep soil is envisioned while pine roots would take up {sup 137}Cs mostly from less contaminated shallow soil layers. The current upward flux of {sup 90}Sr through vegetation appeared at least equal to downward loss in waste material leaching as reported by Dewiere et al. (2004, Journal of Environmental Radioactivity 74, 139-150). Using a prospective calculation model, we estimated that maximum {sup 90}Sr cycling can be expected to occur at 40 years post-planting, resulting in 12% of the current {sup 90}Sr content in the trench transferred to surface soils through biomass turnover and 7% stored in tree biomass. These results are preliminary, although based on accurate methodology. A more integrated ecosystem study leading to the coupling between biological and geochemical models of radionuclide cycling within the Red Forest seems opportune. Such a study would help in the adequate management of that new forest and the waste trenches upon which they reside.

  20. {sup 90}Sr and {sup 137}Cs in the Black Sea after the Chernobyl NPP accident: inventories, balance and tracer applications

    Energy Technology Data Exchange (ETDEWEB)

    Egorov, V.N. [Institute of Biology of the Southern Seas, National Academy of Sciences, Sevastopol (Ukraine); Povinec, P.P. [International Atomic Energy Agency, Marine Environment Laboratory, 4 Quasi Antoine 1 er, BP No. 800, MC-98012 (Monaco); Polikarpov, G.G.; Stokozov, N.A.; Gulin, S.B.; Kulebakina, L.G. [Institute of Biology of the Southern Seas, National Academy of Sciences, Sevastopol (Ukraine); Osvath, I. [International Atomic Energy Agency, Marine Environment Laboratory, 4 Quasi Antoine 1 er, BP No. 800, MC-98012 (Monaco)

    1999-04-01

    The paper summarizes studies of the distributions of {sup 90}Sr and {sup 137}Cs in the water and sediments of the Black Sea carried out during a 10-year period following the 1986 accident at the Chernobyl Nuclear Power Plant. Its goal is to assess the temporal evolution of radionuclide inventories and balances and to evaluate the mixing of water masses and the sedimentation processes using man-made radionuclides as tracers. Using mathematical models and field data, mixing time-scales of 5, 16 and 24 years have been estimated, respectively, for the water layers of depths 0-50, 0-100 and 0-200 m. For the Central Basin the ventilation time of the lower pycnocline is estimated at 15-25 years. {sup 137}Cs has been used to date shelf and deep-basin sediments, providing the history of chemical and radioactive pollution and of eutrophication during the past 50 years. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  1. Soil- and plant-based countermeasures to reduce {sup 137}Cs and {sup 90}Sr uptake by grasses in natural meadows: the REDUP project

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, M. E-mail: miquel.vidal@apolo.qui.ub.es; Camps, M.; Grebenshikova, N.; Sanzharova, N.; Ivanov, Y.; Vandecasteele, C.; Shand, C.; Rigol, A.; Firsakova, S.; Fesenko, S.; Levchuk, S.; Cheshire, M.; Sauras, T.; Rauret, G

    2001-07-01

    The effectiveness of a set of soil- and plant-based countermeasures to reduce {sup 137}Cs and {sup 90}Sr transfer to plants was tested in natural meadows in the area affected by Chernobyl fallout. Countermeasures comprised the use of agricultural practices (disking+ploughing, liming and NPK fertilisation), addition of soil amendments and reseeding with a selection of grass species. Disking+ploughing was the most effective treatment, whereas the K fertiliser doses applied were insufficient to produce a significant increase in K concentration in soil solution. The application of some agricultural practices was economically justifiable for scenarios with a high initial transfer, such as {sup 137}Cs-contaminated organic soils. The use of soil amendments did not lead to a further decrease in transfer. Laboratory experiments demonstrated that this was because of their low radionuclide sorption properties. Finally, experiments examining the effect of plant species on radionuclide transfer showed that both transfer and biomass can depend on the plant species indicating that those with high radionuclide root uptake should be avoided when reseeding after ploughing.

  2. Seasonal variations in activity concentrations of {sup 137}Cs, {sup 40}K, {sup 7}Be, {sup 228}Ac, {sup 99}Tc, {sup 90}Sr, and {sup 239/240}Pu in Fucus vesiculosus and Ascophyllum nodosum from the South-Eastern coast of Norway

    Energy Technology Data Exchange (ETDEWEB)

    Raaum, A.; Christensen, G.C. [Institute for Energy Technology, Health and Safety Dept., Kjeller (Norway)

    2004-07-01

    Brown algae have been proven to be useful indicator organisms for heavy metals and radionuclides in the marine environments due to their ability to concentrate elements from the ambient water. There is quite a lot of data available on {sup 137}Cs in brown algae, especially for Fucus Vesiculosus. Fucus Vesiculosus is also commonly used to monitor the impact of the releases of {sup 99}Tc from the reprocessing plant in Sellafield. There is however a lack of data for other long-lived anthropogenic nuclides as {sup 90}Sr and Pu, and for natural occurring radionuclides. There is also a need for more knowledge about the mechanisms for uptake and accumulation of the different elements, and about different factors influencing the uptake. In this study activity concentrations of {sup 137}Cs, {sup 40}K, {sup 7}Be, {sup 228}Ac, {sup 99}Tc, {sup 90}Sr and {sup 239/240}Pu are measured in whole plants of Fucus vesiculosus and Ascophyllum nodosum collected over a period of one year from the south-eastern coast of Norway. Significant differences between the two species have been found. For {sup 137}Cs, {sup 40}K, {sup 7}Be, {sup 228}Ra and {sup 239/240}Pu, the activity concentrations were significantly higher in Fucus vesiculosus than in Ascophyllum nodosum, whereas for {sup 99}Tc the activity concentrations were higher in Ascophyllum nodosum than in Fucus vesiculosus. There were great seasonal variations in the concentrations of the measured radionuclides. For {sup 99}Tc there was also a difference in the temporal pattern for the two species. Possible uptake mechanisms will be discussed based on the results and on the known physiological differences between the two species. (author)

  3. [The estimation of 90Sr and 137Cs excretion parameters from the organism of wild and laboratory small mammals in vivo, after natural contamination of them in the Chernobyl zone].

    Science.gov (United States)

    Makliuk, Iu A; Gashchak, S P; Maksimenko, A M; Bondar'kov, M D

    2007-01-01

    In the course of laboratory experiment, parameters of 90Sr and 137Cs excretion were estimated in individuals of bank vole Clethrionomys glareolus, captured at one of the most contaminated sites of the Chernobyl zone. The animals were kept under laboratory conditions using "clean" feed during 50 days. The similar investigation was carried out with laboratory mice Mus musculus (Big Blue line) during a longer period (184 days). The measurements of 90Sr content in the animals' body were in vivo carried out, using a specially designed beta-spectrometer with appropriate software, and 137Cs one--by the gamma-spectrometer. During the experiment, the animals had lost less 0.4% of activity due to physical decay of radionuclides. The organism was depurated mainly through biological excretion. In accordance with parameters of one-component exponential decay equation, 99.3% of 137Cs initial content in vole was excreted with half-life period of 2.18 days, and mice--4.4 days (99%). 90Sr excretion had longer half-life period: 11.7 days (56%) in voles, and 49.9 days (87%) in laboratory mice. The rest radionuclides amount of given model was considered as non-excreted from the organism during the observation period. It was determined on the example of voles that 90Sr and 137Cs loss in males was faster than in females, and among females more intensive excretion was in lactating females. 137Cs excretion from the body of bank vole is mainly with urine (74.7%), whereas 90Sr one--with feces and urine in approximately equal amounts. Due to the birth of babies and consequent feeding female lose appreciably less amount of radionuclides body burden than at daily loss with urine and feces.

  4. Decay times of the spin-forbidden and spin-enabled transitions of Yb(2+) doped in CsCaX3 and CsSrX3 (X = Cl, Br, I).

    Science.gov (United States)

    Suta, Markus; Senden, Tim; Olchowka, Jacob; Adlung, Matthias; Meijerink, Andries; Wickleder, Claudia

    2017-03-08

    In this paper, a systematic study of the decay times of the spin-enabled and spin-forbidden transitions of Yb(2+) doped into the halidoperovskites CsMX3 (M = Ca, Sr; X = Cl, Br, I) is presented. The spin-forbidden transitions are characterized by ms decay times, which are typical for Yb(2+). On the contrary, the spin-enabled transitions show much shorter decay times in the range of μs and have so far only been rarely observed. These results allow detailed conclusions about systematics of the decay times of Yb(2+) doped in similar compounds and their correlation to the local structure of the coordination sphere of Yb(2+) as well as the role of vibrational interaction between the excited high spin (HS) and low spin (LS) states. The halidoperovskites are ideally suited as host lattices in this context and may work as text book examples due to their comparable structures, which allows a detailed interpretation of the decay times in relation to the local structure. An understanding of the impact of the composition and structure of the host material on the decay times of Yb(2+) will be of relevance for future applications of this activator in scintillators or lighting materials.

  5. Contamination of terrestrial gastropods Helix aspersa maxima with {sup 137}Cs, {sup 85}Sr, {sup 133}Ba and {sup 123m}Te by direct and trophic pathways

    Energy Technology Data Exchange (ETDEWEB)

    Madoz-Escande, C.; Querrec, N.; Bonhomme, T.; Poncet-Bonnard, D. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

    2004-07-01

    Contaminations of terrestrial gastropod Helix aspersa Maxima by direct deposition or labelled food ingestion of {sup 137}Cs, {sup 85}Sr, {sup 133}Ba and {sup 123m}Te were carried out in laboratory conditions. This study was performed to compare the two pathways of contamination: direct and trophic in terms of individual mortality and, radionuclide uptake, depuration and tissular distribution. A first group of 30 snails (2-year old) was exposed to radioactive aerosols during a twenty-hour period. These aerosols were supposed to be representative of those produced during a nuclear accident occurring on a PWR. A second group of 40 snails (same ages) was submitted to twice-a-week ingestion of food during 10 days (flour at a feeding rate of about 0,2 g) contaminated by these same aerosols. During the 21 days observation period, comparison among the two groups and a reference group (not contaminated by radionuclides) was performed. No significant difference between the three groups was observed neither on the growth nor on the mortality. One day after the deposit, the cesium was the most bioavailable element, distributed homogeneously within the whole body (from 15 to 25% of total Cs respectively in shell and muscle). The strontium accumulated in the shell (about 70%). The barium was found in the muscle (20%) and the shell (65%). Tellurium was mainly present in the shell (70%) and in digestive gland (20%), Later, this element was mostly present in faeces. As regards the contamination by ingestion, it was mainly accumulated in digestive gland. (author)

  6. Estimations of direct release rate of 137Cs and 90Sr to the ocean from the Fukushima Dai-ichi Nuclear Power Plant for five-and-a-half years

    Science.gov (United States)

    Tsumune, Daisuke; Aoyama, Michio; Tsubono, Takaki; Misumi, Kazuhiro; Tateda, Yutaka

    2017-04-01

    A series of accidents at the Fukushima Dai-ichi Nuclear Power Plant (1F NPP) following the earthquake and tsunami of 11 March 2011 resulted in the release of radioactive materials to the ocean by two major pathways, direct release from the accident site and atmospheric deposition. Additional release pathways by river input and runoff from 1F NPP site with precipitation and were also effective for coastal zone in the specific periods before starting direct release on March 26 2011. Direct release from 1F NPP site is dominant one year after the accident. We estimated the direct release rate of 137Cs and 90Sr for more than five-and-a-half years after the accident by the Regional Ocean Model System (ROMS). Direct release rate of 137Cs were estimated for five-and-a-half years after the accident by comparing simulated results and measured activities adjacent to the 1F NPP site(at 5,6 discharge and south discharge). Directly release rate of 137Cs was estimated to be the order of magnitude of 1014 Bq/day and decreased exponentially with time to be the order of magnitude of 109 Bq/day by the end of September 2016. Estimated direct release rate have exponentially reduced with constant rate since November 2011. Apparent half-life of direct release rate was estimated to be 346 days. The estimated total amounts of directly released 137Cs was 3.7±0.7 PBq for five and a half years. Simulated 137Cs activities attributable to direct release were in good agreement with observed activities, a result that implies the estimated direct release rate was reasonable. Simulated 137Cs activity affected off coast in the Fukushima prefecture. We used the measured 137Cs activities by the Tokyo Electric Power Company (TEPCO) for the estimation of direct release. The sea water samples were corrected from the coast. The averaged 137Cs activities from November 2013 to June 2016 were 391 and 383 Bq/m3 at 5,6 discharge and south discharge, respectively. The averaged 137Cs activities measured by the

  7. Coefficients of leaf-fruit translocation for {sup 60}Co, {sup 90}Sr and {sup 137}Cs in bean plant (Phaseolus vulgaris); Coeficientes de translocacao folha-fruto de {sup 60}Co, {sup 90}Sr e {sup 137}Cs em feijoeiro (Phaseolus vulgaris)

    Energy Technology Data Exchange (ETDEWEB)

    Macacini, Jose Flavio

    2000-01-15

    Due to the increasing use of nuclear fission for the generation of electrical energy, the safety aspects of power plants must be minutely appraised. In case of an accident, with liberation of radioactive material into the atmosphere, knowledge about the behavior of plant species when in contact with radionuclides is indispensable. An important route through which agricultural products are contaminated by radionuclides is leaf-fruit translocation. This phenomenon can be evaluated by simulating a fallout contamination in a controlled atmosphere using as a tracer man-made radionuclides. In order to quantity the leaf-fruit translocation coefficients for {sup 60}Co, {sup 90}Sr and {sup 137}Cs in the common bean (Phaseolus vulgaris), variety black diamond, an experiment was carried out in a greenhouse with completely randomized blocks design with six treatments and four blocks. A mixture of these three radionuclides was prepared and used to determine their translocation coefficients. The bean plants were contaminated inside a device especially designed to avoid environmental contamination. In each treatment four vases were sprinkled and one was used to estimate the initial activity of the other three vases. High-resolution gamma-ray spectrometry was used for {sup 60}Co and {sup 137}Cs activity determinations and chemical separation followed by beta counting of {sup 90}Y was used for {sup 90}Sr determinations. The number of treatments was reduced from six to four sprayings corresponding to 30, 45, 60 and 75 days after planting. This reduction was due to the attack of common and gold mosaic viroses. Symptoms were observed on the diseased bean plants 50 days after planting. It was possible, however, to verify a functional dependence between instant of tracer application and the level of physiological development of the bean plant. It was verified that the temporal relationship values for leaf-fruit translocation were similar for {sup 60}Co and {sup 137}Cs. For the {sup 90

  8. Long-lived fission products 90 Sr and 137 Cs from nuclear weapons test fallout and their distribution in the soil. Die Verteilung der langlebigen Spaltprodukte Strontium 90 und Caesium 137 des Kernwaffen-Fallouts im Boden

    Energy Technology Data Exchange (ETDEWEB)

    Gans, I.; Arndt, J.

    1987-01-01

    For this study, samples have been taken down to a depth of 1.30 m, in five sandy soils, three cohesive soils, and one shallow moor. In undisturbed sandy soils, most of the 137 Cs is still near the surface, the mean depth of penetration being between 1.7 and 4.7 cm, so that transport velocities of 0.1 up to 0.3 cm/a are derived for humous upper soil layers. 90 Sr has been detected up to a depth of 1.30 m at some places. As the overall amount of 90 Sr found in the samples has been less than 50% of the amount to be expected from fallout data it is assumed that the missing amount migration to lower strata. The transport velocities derived for 90 Sr in humous upper soil layers are about 1 cm/a, and at least 5 cm/a in the sandy soil layers at greater depths. The distribution coefficients for 90 Sr in humous upper soil layers are 10 cm/sup 3//g and max. 1 cm/sup 3/ in depper sandy soils strata. Due to small depth of penetration of 137 Cs, a distribution coefficient can be assessed only for humous upper soil layers, and is about 100 cm/sup 3//g. Transport velocities assessed for 90 Sr in cohesive soils are about 1 cm/a and thus about the same as in humous upper soil layers of sandy soil. For 137 Cs, only upper limits of 0.02 up to 0.1 cm/a can be given. So the distribution coefficients for 90 Sr assessed to be between 1 and 25 cm/sup 3//g are within the same range as those for humous soils, and for 137 Cs are more than 100 cm/sup 3//g. In shallow moor, the distribution coefficients for 137 Cs and 90 Sr are about the same with about 5 cm/sup 3//g. (orig./HP) With 9 figs., 29 tabs.

  9. Effect of solution-to-solid ratio on the sorption of Sr{sup 2+} and Cs{sup +} on bentonite

    Energy Technology Data Exchange (ETDEWEB)

    Oscarson, D.W.; Hume, H.B.

    1996-10-01

    Sorption parameters in the form of distribution coefficients, K{sub d}, are important components of some models used to predict the rate of contaminant migration in earthen materials. Values of K{sub d} were measured in batch tests for trace levels (c{sub o} {approx_equal} 10{sup -9} M) of {sup 85}Sr{sup 2+} and {sup 137}Cs{sup +} on Na{sup -} and Ca{sup -} bentonite in both a compacted (dry bulk density ranged from 0.6 to 1.8 Mg/m{sup 3}) and an uncompacted state as a function of solution-to-solid ratio. The time to reach equilibrium varied from hours for uncompacted bentonite to several months for compacted clay. This time difference is due to the slower diffusion of the sorbates to sorption sites on compacted clay. For both sorbates, K{sub d} Values increased with increasing solution-to-solid ratio, were greater for Na- than Ca-bentonite, and were one-half to one-third lower for compacted than for uncompacted clay. The last result is attributed to an inaccessibility of some sorption sites on compacted clay or to slight differences in solution composition. The applicability of the results to contaminant migration in the field will be discussed.

  10. Mathematical Modeling of a Cs(I – Sr(II – Bentonite – Magnetite Sorption System, Simulating the Processes Taking Place in a Deep Geological Repository

    Directory of Open Access Journals (Sweden)

    H. Filipská

    2005-01-01

    Full Text Available The derivation of mathematical models of systems consisting of Cs(I or Sr(II and of bentonite (B, magnetite (M or their mixtures (B+M are described. The paper deals especially with modeling of the protonation and sorption processes occurring on the functional groups of the solid phase, namely on so called edge sites and layer sites. The two types of sites have different properties and, as a result, three types of Surface Complexation Models (SCM are used for edge sites, viz. two electrostatic SCMs: the Constant Capacitance Model (CCM and the Diffusion Double Layer Model (DLM, and one without electrostatic correction: the Chemical Model (CEM. The processes taking place on the layer sites are described by means of the Ion Exchange Model (IExM. In the course of modeling, the speciation of the given metal in the liquid (aqueous phase has to be taken into account. In principle, the model of protonation or sorption processes is based on the reactions occurring in the aqueous phase and on the surface of the solid phase, and comprises not only the equations of the equilibrium constants of the individual reactions, but also the mass and charge balance equations. The algorithm of the numerical solution is compatible with FAMULUS 3.5 (a Czech software product quite extensively used at Czech universities in the last decade, the bookcase codes of which are utilized. 

  11. CONTENT OF 137CS AND 90SR IN THE MEDICINAL AND OTHER ECONOMICALLY VALUABLE PLANT SPECIES FROM THE KORMYANSKY DISTRICT OF THE GOMEL REGION OF THE BELARUS REPUBLIC EDUCATIONAL ORGANIZATION «GOMEL STATE UNIVERSITY AFTER F. SKORINA»

    Directory of Open Access Journals (Sweden)

    L. M. Sapegin

    2011-01-01

    Full Text Available Investigation results of the contamination with 137Cs and 90Sr of the plants from natural ecosystems of four objects are being presented. 45 plant samples and 24 soil samples were analyzed. It was revealed that the permissible level for the 137Cs content of 370 Bq/kg, is exceeded for 21 samples (46.7 %. Content of 90Sr in plants varied from 3 Bq/kg to 544 Bq/kg. Most part of the radionuclides still remains in the upper soil horizons. Plant species specificity concerning the radionuclide accumulation depends on the composition of the natural ecosystem, type of soil, its agrochemical composition and humidity.

  12. Appendix to Health and Safety Laboratory environmental quarterly report. [Fallout radionuclides deposited and in surface air at various world sites; /sup 137/Cs and /sup 90/Sr in milk and drinking water in New York City; and stable Pb in surface air

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, E.P. Jr.

    1977-07-01

    Tabulated data are presented on the deposition of fallout /sup 89/Sr and /sup 90/Sr at various world land sites through 1976; the ..gamma.. spectra and content of /sup 7/Be, /sup 95/Zr, /sup 137/Cs, /sup 144/Ce, /sup 90/Sr, /sup 210/Pb, /sup 238/Pu, /sup 239/Pu, and stable Pb in samples of surface air collected during 1966 at various world sites; and the content of fallout /sup 137/Cs and /sup 90/Sr in samples of drinking water and milk collected in New York City through 1976. (CH)

  13. Ultra-trace determination of (90)Sr, (137)Cs, (238)Pu, (239)Pu, and (240)Pu by triple quadruple collision/reaction cell-ICP-MS/MS: Establishing a baseline for global fallout in Qatar soil and sediments.

    Science.gov (United States)

    Amr, Mohamed A; Helal, Abdul-Fattah I; Al-Kinani, Athab T; Balakrishnan, Perumal

    2016-03-01

    The development of practical, fast, and reliable methods for the ultra-trace determination of anthropogenic radionuclides (90)Sr, (137)Cs, (238)Pu, (239)Pu, and (240)Pu by triple quadruple collision/reaction cell inductively coupled plasma mass spectrometry (CRC-ICP-MS/MS) were investigated in term of its accuracy and precision for producing reliable results. The radionuclides were extracted from 1 kg of the environmental soil samples by concentrated nitric and hydrochloric acids. The leachate solutions were measured directly by triple quadrupole CRC-ICP-MS/MS. For quality assurance, a chemical separation of the concerned radionuclides was conducted and then measured by single quadrupole-ICP-MS. The developed methods were next applied to measure the anthropogenic radionuclides (90)Sr, (137)Cs, (238)Pu, (239)Pu, and (240)Pu in soil samples collected throughout the State of Qatar. The average concentrations of (90)Sr, (137)Cs, (238)Pu, (239)Pu, and (240)Pu were 0.606 fg/g (3.364 Bq/kg), 0.619 fg/g (2.038 Bq/kg), 0.034 fg/g (0.0195 Bq/kg), 65.59 fg/g (0.150 Bq/kg), and 12.06 fg/g (0.103 Bq/kg), respectively.

  14. Numerical Modeling of 90Sr and 137Cs Transport from a Spill in the B-Cell of the 324 Building, Hanford Site 300 Area

    Energy Technology Data Exchange (ETDEWEB)

    Rockhold, Mark L.; Bacon, Diana H.; Freedman, Vicky L.; Lindberg, Michael J.; Clayton, Ray E.

    2012-03-19

    To characterize the extent of contamination under the 324 Building, a pit was excavated on the north side of the building in 2010 by Washington Closure Hanford LLC (WCH). Horizontal closed-end steel access pipes were installed under the foundation of the building from this pit and were used for measuring temperatures and exposure rates under the B-Cell. The deployed sensors measured elevated temperatures of up to 61 C (142 F) and exposure rates of up to 8,900 R/hr. WCH suspended deactivation of the facility because it recognized that building safety systems and additional characterization data might be needed for remediation of the contaminated material. The characterization work included additional field sampling, laboratory measurements, and numerical flow and transport modeling. Laboratory measurements of sediment physical, hydraulic, and geochemical properties were performed by Pacific Northwest National Laboratory (PNNL) and others. Geochemical modeling and subsurface flow and transport modeling also were performed by PNNL to evaluate the possible extent of contamination in the unsaturated sand and gravel sediments underlying the building. Historical records suggest that the concentrated 137Cs- and 90Sr-bearing liquid wastes that were spilled in B-Cell were likely from a glass-waste repository testing program associated with the Federal Republic of Germany (FRG). Incomplete estimates of the aqueous chemical composition (no anion data provided) of the FRG waste solutions were entered into a geochemical speciation model and were charge balanced with nitrate to estimate waste composition. Additional geochemical modeling was performed to evaluate reactions of the waste stream with the concrete foundation of the building prior to the stream entering the subsurface.

  15. Appendix to Health and Safety Laboratory environmental quarterly, March 1, 1976--June 1, 1976. [Tabulated data on content of lead in surface air and /sup 7/Be, /sup 95/Zr, /sup 137/Cs, /sup 144/Ce, and /sup 90/Sr in surface air, milk, drinking water, and foods sampled in USA

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, E.P. Jr.

    1976-07-01

    Tabulated data are presented on: the monthly deposition of /sup 89/Sr and /sup 90/Sr at some 100 world land sites; the content of lead and /sup 7/Be, /sup 95/Zr, /sup 137/Cs, and /sup 144/Ce in samples of surface air from various world sites; and the content of /sup 90/Sr in samples of milk, drinking water, and animal and human diets collected at various locations throughout the USA. (CH)

  16. Combination of chemical separation and data treatment for {sup 55}Fe, {sup 63}Ni, {sup 99}Tc, {sup 137}Cs and {sup 90}Sr/{sup 90}Y activity determination in radioactive waste by liquid scintillation

    Energy Technology Data Exchange (ETDEWEB)

    Mellado, J. [Departament de Quimica Analitica, Facultat de Quimica, Universitat de Barcelona, C/Marti Franques 1, 08028 Barcelona (Spain); Tarancon, A. [Departament de Quimica Analitica, Facultat de Quimica, Universitat de Barcelona, C/Marti Franques 1, 08028 Barcelona (Spain); Garcia, J.F. [Departament de Pintura, Facultat de Belles Arts, Universitat de Barcelona, C/Pau Gargallo 4, 08028 Barcelona (Spain)]. E-mail: jfgarcia@apolo.qui.ub.es; Rauret, G. [Departament de Quimica Analitica, Facultat de Quimica, Universitat de Barcelona, C/Marti Franques 1, 08028 Barcelona (Spain); Warwick, P. [Geoscience Advisory Unit, Southampton Oceanography Centre, Southampton SO14 3ZH (United Kingdom)

    2005-08-01

    Routine operations involving nuclear reactors and decommissioning activities require numerous chemical analyses. Most of the procedures developed for these chemical characterisations involve several separation steps to prepare the sample for measurement. Chemical treatments are time- and manpower-consuming, labour intensive and produce significant quantities of waste. In order to address this problem, we evaluate a data treatment procedure (multivariate calibration-PLS), which we propose as a substitute to some of these separation steps. Mixtures of beta emitter radionuclides of increasing complexity ({sup 90}Sr/{sup 90}Y-{sup 99}Tc, {sup 90}Sr/{sup 90}Y-{sup 99}Tc-{sup 63}Ni-{sup 137}Cs and {sup 90}Sr/{sup 90}Y-{sup 99}Tc-{sup 63}Ni-{sup 137}Cs-{sup 55}Fe) have been measured by liquid scintillation (LS) counting. The influences of quenching and level of activity was evaluated and the activity of unknown samples determined. Despite the spectra overlapping and low resolution of LS, relative errors in the activities quantification of unknown samples inside the range covered by the calibration matrix are lower than 15% whatever the number of radionuclides included in the solution was.

  17. Effect of mycorrhizal infection on root uptake by pine seedlings and redistribution of three contrasting radio-isotopes: {sup 85}Sr, {sup 95m}Tc and {sup 137}Cs

    Energy Technology Data Exchange (ETDEWEB)

    Plassard, C.; Ladeyn, I.; Staunton, S. [Institut National de Recherches Agronomiques (INRA), UMR Rhizosphere and Symbiose 34 - Montpellier (France)

    2004-07-01

    Mycorrhizal infection is known to improve phosphate nutrition and water supply of higher plants. It has been reported to both increase the uptake of potentially toxic pollutant elements and to protect plants against toxic effects. Little is known about the effect of mycorrhizal infection on the dynamics of radioactive pollutants in soil-plant systems. The aim of this study was to compare the root uptake and root-shoot transfer of three radio-isotopes with contrasting chemical properties ({sup 85}Sr, {sup 95m}Tc and {sup 137}Cs) in mycorrhizal and control, non mycorrhizal plants. The plant studied was Pinus pinaster and the associated ecto-mycorrhizal fungus was Rhizopogon roseolus (strain R18-2). Plants were grown under anoxic conditions for 3 months then transferred to thin layers of autoclaved soil and allowed to grow for four months. After this period, the rhizotrons were dismantled, and plant tissue analysed. Biomass, nutrient content (K, P, N, Ca) and activities of each isotope in roots, shoots and stems were measured, and the degree of mycorrhizal infection assessed. The transfer factors decreased in the order Tc>Sr>Cs as expected from the degree of immobilisation by soil. No effect of mycorrhizal infection on root uptake was observed for Sr. Shoot activity concentration of Tc was decreased by mycorrhizal infection but root uptake correlated well with mycelial soil surface area. In contrast, Cs shoot activity was greater in mycorrhizal than control plants. The uptake and root to shoot distribution shall be discussed in relation to nutrient dynamics. (author)

  18. Mycorrhizal association of maritime pine, Pinus pinaster, with Rhizopogon roseolus has contrasting effects on the uptake from soil and root-to-shoot transfer of {sup 137}Cs, {sup 85}Sr and {sup 95m}Tc

    Energy Technology Data Exchange (ETDEWEB)

    Ladeyn, Ingrid; Plassard, Claude [INRA, UMR 1222, Biogeochimie du Sol et de la Rhizosphere, place Viala, 34060 Montpellier (France); Staunton, Siobhan [INRA, UMR 1222, Biogeochimie du Sol et de la Rhizosphere, place Viala, 34060 Montpellier (France)], E-mail: staunton@montpellier.inra.fr

    2008-05-15

    The beneficial role of mycorrhizal association on plant nutrition and water supply is well-known, however, very little information exists with respect to the availability of radionuclides. We have measured the effect of controlled mycorrhizal association on the root uptake from soil and accumulation in leaves of three radionuclides. The radionuclides have contrasting chemical and biological properties: Cs is strongly adsorbed on soil, has no biological role and is a close analogue of potassium; Sr is less strongly adsorbed on soil and behaves very similarly to calcium; and Tc is very mobile in soil as pertechnetate, but immobilised when reduced to Tc(IV), it is also considered to be easily assimilated by biological systems. We found that mycorrhizal association had no effect on root-to-needle transfer of Cs, but increased root uptake and that this increase could not be explained by improved potassium nutrition. In contrast, the symbiotic relation decreased Tc soil-to-needle transfer, but this resulted from complex dynamics of root uptake and rapid immobilisation of Tc in soil. No effect of mycorrhizal association on Sr, like its stable analogue Ca, was observed. The addition of a phytotoxic metal, Cu, inhibited mycorrhizal association, thus eliminating the effects observed for non-contaminated plant-fungus couples, but had no additional effect on radionuclide dynamics.

  19. First-principles study of fission product (Xe, Cs, Sr) incorporation and segregation in alkaline earth metal oxides, HfO2, and MgO-HfO2 interface

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiang-yang [Los Alamos National Laboratory; Uberuaga, Blas P [Los Alamos National Laboratory; Sickafus, Kurt E [Los Alamos National Laboratory

    2008-01-01

    In order to close the nuclear fuel cycle, advanced concepts for separating out fission products are necessary. One approach is to use a dispersion fuel form in which a fissile core is surrounded by an inert matrix that captures and immobilizes the fission products from the core. If this inert matrix can be easily separated from the fuel, via e.g. solution chemistry, the fission products can be separated from the fissile material. We examine a surrogate dispersion fuel composition, in which hafnia (HfO{sub 2}) is a surrogate for the fissile core and alkaline earth metal oxides are used as the inert matrix. The questions of fission product incorporation in these oxides and possible segregation behavior at interfaces are considered. Density functional theory based calculations for fission product elements (Xe, Sr, and Cs) in these oxides are carried out. We find smaller incorporation energy in hafnia than in MgO for Cs and Sr, and Xe if variation of charge state is allowed. We also find that this trend is reversed or reduced for alkaline earth metal oxides with large cation sizes. Model interfacial calculations show a strong tendency of segregation from bulk MgO to MgO-HfO{sub 2} interfaces.

  20. {sup 90}Sr, {sup 238}U, {sup 234}U, {sup 137}Cs, {sup 40}K and {sup 239/240}Pu in Emmental type cheese produced in different regions of Western Europe

    Energy Technology Data Exchange (ETDEWEB)

    Froidevaux, P. E-mail: pascal.froidevaux@inst.hospvd.ch; Geering, J.-J.; Pillonel, L.; Bosset, J.-O.; Valley, J.-F

    2004-07-01

    A method is presented for the determination of {sup 90}Sr and uranium in Emmental type cheese collected in dairy plants from different European countries. Results display a significant correlation (r=0.708, Student t-test=6.02) between the {sup 90}Sr content of the cheese and the altitude of grazing. The highest {sup 90}Sr activity is 1.13 Bq kg{sup -1} of cheese and the lowest is 0.29 Bq kg{sup -1}. Uranium activity is very low with a highest {sup 238}U value of 27 mBq kg{sup -1}. In addition, {sup 234}U/{sup 238}U ratio shows a large enrichment in {sup 234}U for every location. Without any significant indication of the geographic origin of the cheese, this enrichment is believed to be due to the geological features of the pasture, soil and underground water. These results tend to prove that the contamination of milk by uranium originates principally from the water that the cows drink instead of the forage. This finding may have a great importance in models dealing with dairy food contamination by radionuclides following a nuclear accident. Also, the {sup 90}Sr content and to a lesser extent the {sup 234}U/{sup 238}U ratio could be used to trace the authenticity of the origin of the cheese. {sup 137}Cs activity is lower than the detection limit of 0.1 Bq kg{sup -1} in all the samples collected (n=20). Based on natural {sup 40}K activity in cheese (15-21 Bq kg{sup -1}), the decontamination factor for the alkaline cations from milk to cheese is about 20. Plutonium activity stays below the detection limit of 0.3 mBq kg{sup -1}.

  1. Cs-corrected scanning transmission electron microscopy investigation of dislocation core configurations at a SrTiO(3)/MgO heterogeneous interface.

    Science.gov (United States)

    Zhu, Yuanyuan; Song, Chengyu; Minor, Andrew M; Wang, Haiyan

    2013-06-01

    Heterostructures and interfacial defects in a 40-nm-thick SrTiO(3) (STO) film grown epitaxially on a single-crystal MgO (001) were investigated using aberration-corrected scanning transmission electron microscopy and geometric phase analysis. The interface of STO/MgO was found to be of the typical domain-matching epitaxy with a misfit dislocation network having a Burgers vector of ½ a(STO) . Our studies also revealed that the misfit dislocation cores at the heterogeneous interface display various local cation arrangements in terms of the combination of the extra-half inserting plane and the initial film plane. The type of the inserting plane, either the SrO or the TiO(2) plane, alters with actual interfacial conditions. Contrary to previous theoretical calculations, the starting film planes were found to be dominated by the SrO layer, i.e., a SrO/MgO interface. In certain regions, the starting film planes change to the TiO(2)/MgO interface because of atomic steps at the MgO substrate surface. In particular, four basic misfit dislocation core configurations of the STO/MgO system have been identified and discussed in relation to the substrate surface terraces and possible interdiffusion. The interface structure of the system in reverse--MgO/STO--is also studied and presented for comparison.

  2. Contamination of terrestrial gastropods, Helix aspersa maxima, with {sup 137}Cs, {sup 85}Sr, {sup 133}Ba and {sup 123m}Te by direct, trophic and combined pathways

    Energy Technology Data Exchange (ETDEWEB)

    Madoz-Escande, C. [Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, IRSN/DEI/SECRE/LRE, Cadarache, Bld 186, BP 3, 13115 St-Paul-lez-Durance Cedex (France)]. E-mail: chantal.madoz-escande@irsn.fr; Simon, O. [Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, IRSN/DEI/SECRE/LRE, Cadarache, Bld 186, BP 3, 13115 St-Paul-lez-Durance Cedex (France)

    2006-07-01

    {sup 137}Cs, {sup 85}Sr, {sup 133}Ba and {sup 123m}Te contaminations of terrestrial gastropods, Helix aspersa maxima, by direct deposition, labelled food ingestion or combined (trophic and direct pathways) exposure were carried out under laboratory conditions. The aim of this study was to compare the three contamination pathways: direct, trophic and combined, in terms of individual mortality, radionuclide uptake, depuration and distribution in the tissues. An initial group of 30 snails (2 years old) was exposed to radioactive aerosols during a 20-h period. These aerosols were assumed to be representative of those that would be released during a nuclear accident occurring in a PWR. A second group of 50 snails (same age) was submitted to an ingestion of commercial food contaminated by the same aerosols, twice a week for 21 days (flour at a feeding rate of about 0.2 g). A third group of 40 snails was submitted to a combined exposure: exposure to radioactive aerosols (20 h), followed by ingestion of flour contaminated by the same aerosols, twice a week for 21 days. No significant difference between the three groups and a reference group of 10 snails was observed, neither in growth nor in mortality. Concerning the direct pathway, at the end of direct deposition (about 1 day after the beginning), cesium was the most bioavailable element, distributed rather homogeneously throughout the whole body (13% of the total Cs in all organs excepting the digestive system and 28% in the muscle). Strontium was measured in the shell (about 70%). Barium was found in the muscle (20%) and in the shell (65%). Tellurium was mainly present in the shell (70%) and in the digestive system (20%). After 21 days of depuration, the faeces eliminated 42% of the Te. As for contamination by ingestion, Te mainly accumulated in the digestive system (72% of Te present in the total body), Ba accumulated in the muscle (75%) and Sr in the shell (70%). Concerning contamination by combined pathways, at the

  3. Fabrication and characterization of SrAl{sub 2}O{sub 4}: Eu{sup 2+} Dy{sup 3+}/CS-PCL electrospun nanocomposite scaffold for retinal tissue regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Sepahvandi, Azadeh; Eskandari, Mahnaz, E-mail: eskandarim@aut.ac.ir; Moztarzadeh, Fathollah

    2016-09-01

    Millions of people around the world become blind due to losing a part of the retina cells. In tissue engineering field one way to address this issue is to develop a retina tissue by scaffolds based on structure and signals received These scaffolds can play an essential role in repair and reformation of the damaged retina tissue. Here, SrAl{sub 2}O{sub 4}: Eu{sup 2+}, Dy{sup 3+} nanophosphor were prepared by sol-gel method and then coated with PEG to become biocompatible. Next 10%, 30% and 50% concentration of the coated nanophosphors were dispersed in CS-PCL copolymer and electrospuned to form SrAl{sub 2}O{sub 4}: Eu{sup 2+}, Dy{sup 3+}/CS-PCL scaffolds. The aforementioned photo –luminescence-scaffolds were studied for their optical, mechanical and morphological characteristics finally the effect of these scaffolds on the mice RPCs cells' proliferation and differentiation was observed. The 30% nanophosphor dispersion scaffold while providing adequate mechanical flexibility and integrity, and exhibiting superior proliferation rates and acceptable differentiation into retinal neural cells (particularly photo receptors retinal) is suggested as a promising choice in retinal tissue repair. - Highlights: • The 30% nanophosphor dispersion scaffold for both shorter wavelength and middle intense emission is more near to biocompatible nanophosphors. • 30% dispersed nanophosphor scaffold displays satisfactory mechanical strength and flexibility where its behavior is similar to the retina tissue. • Besides as the most effective signal in this study is the electromagnetic signals emitted by nanophosphors, we attribute the enhanced proliferation to the positive effects of the later, the emitted signals of scaffolds. • The tendency towards spherical morphology implies that emitting light may stimulate the cell signaling toward differentiation • These findings implies that mRPC grown on SrAl{sub 2}O{sub 4}: Eu{sup 2+},Dy{sup 3+}/CS-PCL scaffolds in differentiation

  4. Study of influence of plastic scintillators thicknesses to detect Beta particles and Gamma radiation by means of spectral analysis of {sup 90}Sr, {sup 90}Y and {sup 137}Cs sources

    Energy Technology Data Exchange (ETDEWEB)

    Cardenas, Jose Patricio Nahuel; Filho, Tufic Madi; Pereira, Maria da Conceicao Costa; Santos, Brianna B. dos; Correa, Eduardo de L.; Santos, Lucas Rodrigues dos; Lopes, Anderson Figueredo; Silva, Alexandre F.P. da; Santos, Diogo F. dos; Camilo, Douglas de S.; Purgato, Rafael T.; Aredes, Vitor O.G. [Nuclear and Energy Research Institute, IPEN-CNEN/SP, Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP, Av. Prof. Lineu Prestes 2242 Cid Universitaria CEP: 05508-000- Sao Paulo-SP (Brazil)

    2015-07-01

    The Nuclear and Energy Research Institute - IPEN, offers post-graduate programs, namely: Nuclear Technology - Applications (TNA), Nuclear Technology - Materials (TNM), Nuclear Technology - Reactors (TNR). The Institute programs mission is to form expert technicians, physicists and engineers with a strong knowledge in their discipline to work in the nuclear area. The course: 'Theoretical Fundamentals and Practices of the Instrumentation used in Nuclear Data Acquisition' covers the use of laboratory nuclear instrumentation and the accomplishment of experiments to obtain nuclear parameters. One of these experimental exercises is object of this work: 'Study of influence of plastic scintillators to detect Beta particles and Gamma radiation by means of spectral analysis of {sup 90}Sr, {sup 90}Y and {sup 137}Cs sources'. The use of scintillators plastic for the detection has the advantage of low cost, high mechanical strength, is not hygroscopic and can be manufactured in large volumes. This work aims to present the analysis of relative efficiency of detection of plastic scintillators of various thicknesses for beta particles and gamma radiation by the spectrum of {sup 137}Cs and {sup 90}Sr. Due to lack of resolution of the detectors plastic scintillators we worked with relative efficiency. The evaluation was done by reading deposited energy, using the software MAESTRO, for each detector thickness. For beta particles was observed an ideal thickness around 3 mm and the better photon efficiency was observed with increasing the thickness of the detector. The present experiment does not intend to establish a new technique for this subject: it solely aims student's practical exercises in nuclear properties of elements and detectors being part of the nuclear experimental course. (authors)

  5. Sequential determination of natural ({sup 232}Th, {sup 238}U) and anthropogenic ({sup 137}Cs, {sup 90}Sr, {sup 241}Am, {sup 239+240}Pu) radionuclides in environmental matrix

    Energy Technology Data Exchange (ETDEWEB)

    Michel, H.; Levent, D.; Barci, V.; Barci-Funel, G.; Hurel, C. [Laboratoire de Radiochimie, Sciences Analytiques et Environnement (LRSAE), Universite de Nice Sophia-Antipolis 06108 Nice Cedex (France)

    2008-07-01

    A new sequential method for the determination of both natural (U, Th) and anthropogenic (Sr, Cs, Pu, Am) radionuclides has been developed for application to soil and sediment samples. The procedure was optimised using a reference sediment (IAEA-368) and reference soils (IAEA-375 and IAEA-326). Reference materials were first digested using acids (leaching), 'total' acids on hot plate, and acids in microwave in order to compare the different digestion technique. Then, the separation and purification were made by anion exchange resin and selective extraction chromatography: Transuranic (TRU) and Strontium (SR) resins. Natural and anthropogenic alpha radionuclides were separated by Uranium and Tetravalent Actinide (UTEVA) resin, considering different acid elution medium. Finally, alpha and gamma semiconductor spectrometer and liquid scintillation spectrometer were used to measure radionuclide activities. The results obtained for strontium-90, cesium-137, thorium-232, uranium- 238, plutonium-239+240 and americium-241 isotopes by the proposed method for the reference materials provided excellent agreement with the recommended values and good chemical recoveries. (authors)

  6. Improved frequency measurement of the $^1S_{0}$-$^3P_{0}$ clock transition in $^{87}$Sr using the Cs fountain clock at NMIJ as a transfer oscillator

    CERN Document Server

    Tanabe, Takehiko; Kobayashi, Takumi; Takamizawa, Akifumi; Yanagimachi, Shinya; Ikegami, Takeshi; Suzuyama, Tomonari; Inaba, Hajime; Okubo, Sho; Yasuda, Masami; Hong, Feng-Lei; Onae, Atsushi; Hosaka, Kazumoto

    2015-01-01

    We performed an absolute frequency measurement of the $^1S_{0}$-$^3P_{0}$ transition in $^{87}$Sr with a fractional uncertainty of $1.2 \\times 10^{-15}$, which is less than one third that of our previous measurement. A caesium fountain atomic clock was used as a transfer oscillator to reduce the uncertainty of the link between a strontium optical lattice clock and the SI second. The absolute value of the transition frequency is 429 228 004 229 873.56(49) Hz.

  7. A study of internal contamination levels resulting from {sup 90}Sr and {sup 137}Cs environmental pollution. The influence of different factors; Etude des niveaux de contamination interne resultant d'une pollution de l'environnement par le {sup 90}Sr et le {sup 137}Cs influence des differents parametres

    Energy Technology Data Exchange (ETDEWEB)

    Garnier, A. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1970-07-01

    This study includes two parts. The purpose of the former one is to try and evaluate the amounts of {sup 90}Sr and {sup 137}Cs dietary intakes as a function of age with a view to assessing internal exposure doses and estimating the critical age, and to study the relative significance of the several factors it depends on. The data used are both the results of dietary surveys made in 11 districts of the European community from which the evolution of the consumed amounts of 13 groups of foodstuffs, as a function of age was derived, and the mean factors of contamination pathways. The variability of some factors is very large and an attempt is made to assess their significance on the whole contamination; also, the influence of the various diets has been emphasized. The purpose of the second part is to assess, doses as a function of age in the case of protracted exposure on the basis of the aforesaid results and radiobiological factors derived from bibliographic states of the arts. An assessment is made of body burdens and mean doses (either to the skeleton or the whole body according to the radionuclides) originating either from a direct unitary exposure or from situations implying both modes of exposure. As assumed only the diets vary with the districts, thus the results reflect their significance which should be corrected, for a more accurate assessment of the dose variability, by the significance of human and transfer factors. (author) [French] Cette etude comprend deux parties. L'objet de la premiere partie est a la fois un essai d'evaluation en fonction de l'age des quantites de strontium 90 et de cesium 137 ingerees avec les aliments dans la perspective d'une application a l'estimation des doses d'irradiation interne et a la recherche de l'age critique, et une etude de l'influence relative des divers parametres dont elle depend. Les donnees utilisees sont, d'une part, les resultats des enquetes alimentaires faites en

  8. Effects of soluble organic complexants and their degradation products on the removal of selected radionuclides from high-level waste. Part 3, Distributions of Sr, Cs, Tc, Pu, and Am onto 33 absorbers from four variations of a 3:1 dilution of Hanford complexant concentrate (CC) simulant: Part 4, The effects of varying dilution ratios on the distributions of Sr, Cs, Tc, Pu, and Am onto 12 absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Marsh, S.F. [Sandia National Labs., Albuquerque, NM (United States); Svitra, Z.V.; Bowen, S.M. [Los Alamos National Lab., NM (United States)

    1995-09-01

    Many of the radioactive waste storage tanks at USDOE facilities contain organic compounds that have been degraded by radiolysis and chemical reactions during decades of storage. Objective of this study was to measure effects of soluble organic complexants and their degradation products on sorption of Sr, Cs, Tc, Pu and Am onto 33 absorbers that in the absence of these organic compounds offer high sorption of these elements. The elements were in a generic simulant for Hanford complexant concentrate supernate that initially contained six organic complexants: EDTA, HEDTA, NTA, citrate, gluconate, and iminodiacetate. This simulant was tested as prepared and after gamma-irradiation to approximately 34 Mrads. Two other variations consisted of the unirradiated and irradiated simulants after treatment at 450C and 15,000 psi in a hydrothermal organic-destruction process. These experiments were conducted with a 3:1 water-to-simulant dilution of each of the four simulant variations. To determine effects of varying dilution ratios on the sorption of these five elements from the unirradiated and gamma-irradiated simulants that were not treated with the hydrothermal process, we measured their distribution from a 1:1 dilution, using 1 M NaOH as the diluent, onto the 12 best-performing absorbers. We then measured the sorption of these five elements from solutions having diluent-simulant ratios of 0, 0.5, 2.0, and 3.0 onto the three absorbers that performed best for sorbing Sr, Pu and Am from the 1:1 dilution. For each of 900 element/absorber/solution combinations, we measured distribution coefficients (Kd values) twice for each period for dynamic contact periods of 30 min, 2 h, and 6 h to obtain information about absorber stability and sorption kinetics. The 5400 measured Kd values indicate that the sorption of Sr, Pu, and Am is significantly decreased by the organic complexants in these simulant solutions, whereas the sorption of Cs and Tc is much less affected.

  9. Chôra

    DEFF Research Database (Denmark)

    Isar, Nicoletta

    2009-01-01

    , for whom "il y a khôra" (there is chôra), Sallis keeps the definite article (the chôra) as an index of certain differentiation in chôra. This article takes as a point of departure Sallis' thesis regarding the manifestation of the chôra, grounded in the manner in which the chôra is apprehended, that is...

  10. "Redefining RA": The RA Tool Kit

    Science.gov (United States)

    Wyatt, Neal

    2008-01-01

    No one likes being two steps behind, and the fastest way to fall off the pace is by not keeping up with major titles and hot authors. Fortunately, there are numerous resources, both prepublication and postpublication, that can help. It is best when readers' advisory (RA) librarians know what is coming out months ahead of time--in order to think…

  11. Conceptual and numerical modelling of radionuclide transport in near-surface systems at Forsmark. SR-Site Biosphere

    Energy Technology Data Exchange (ETDEWEB)

    Pique, Angels; Grandia, Fidel; Sena, Clara; Arcos, David; Molinero, Jorge; Duro, Lara; Bruno, Jordi (Amphos21 Consulting S.L., Barcelona (Spain))

    2010-11-15

    In the framework of the SR-Site safety assessment, a conceptual and numerical modelling of radionuclide reactive transport in near-surface systems (including till and clay systems) at Forsmark has been carried out. The objective was to evaluate the retention capacity of the near-surface systems, composed of Quaternary deposits, which would be the last natural barrier for an eventual radionuclide release from the deep repository prior to reaching the biosphere. The studied radionuclides are 14C, 129I, 36Cl, 94Nb, 59Ni, 93Mo, 79Se, 99Tc, 230Th, 90Sr, 226Ra, 135Cs and U. Conceptual description and numerical simulations of radionuclide reactive transport show that cation exchange and surface complexation on illite are active processes for the retention of several radionuclides (U, Th, Ni, Cs, Sr, Ra). Surface complexation on iron hydroxide is an active process in the till system, able to effectively retain U and Ni. Another retention process of importance is the incorporation of the radionuclides into mineral phases, either by the precipitation of pure phases or solid solutions. Quantitative modelling has been useful to illustrate the incorporation of C and Sr in the carbonate solid solution in the considered model domains (till and clay), as well as the precipitation of uraninite in the clay sediments and the precipitation of native selenium and radiobarite in the till. Other mineral phases that could, a priori, retain U, Se, Nb and Tc do not precipitate in the simulations, either due to the pH-Eh conditions and/or because the dissolved concentration of the element is not high enough under the considered simulation conditions. It is important to keep in mind that changes in these parameters and in the boundary conditions could modify the predicted behaviour of these elements. The radionuclides that are most significantly retarded are Th, Ni and Cs, mainly through sorption onto illite. Therefore, if the amount of illite (or available sorption sites) decreases, the

  12. Chôra

    DEFF Research Database (Denmark)

    Isar, Nicoletta

    2009-01-01

    , as in a dream. Sallis' interpretation opens up the possibility for a new reading of the dialogue, and offers a tool to examine phenomena occurred in the aftermath of the Platonic cosmogony. One of the most fascinating episodes of the afterlife of the Platonic chôra is the Byzantine chôra, presented...

  13. Study on Adsorptive Property of Clay for Strontium and Caesium%Sr~(2+)、Cs~+在粘土中的吸附性能研究

    Institute of Scientific and Technical Information of China (English)

    叶正中; 易发成

    2011-01-01

    采用间歇法研究在不同实验条件下(浓度、固液比、粒径、pH),选用的粘土对Sr2+、Cs+的吸附性能。实验结果表明:室温条件下,Sr2+、Cs+溶液浓度和固液比对红粘土的吸附性能影响较大;红粘土对Cs+的吸附性能优于对Sr2+的吸附性能,当浓度为10 mg/L时,粘土对Cs+的吸附效率可达88%。%An intermittence method was adopted to study the adsorption of clay for Sr2+(strontium) and Cs+(caesium) under various conditions including different concentration,solid-to-liquid ratio,adsorbent size and pH value.The results showed that adsorptive capacity depended on the concentration and solid-to-liquid ratio at room temperature.The absorption of clay for Sr2+ was better than that for Cs+.When the concentration was 10 mg/L,the remove rate of clay for Cs+ was 88%.

  14. Towards a Precise Measurement of Atomic Parity Violation in a Single Ra+ Ion

    NARCIS (Netherlands)

    Jungmann, K.; Giri, G. S.; Versolato, O. O.; Steadman, SG; Stephans, GSF; Taylor, FE

    2012-01-01

    In the singly charged Ra+ ion the contributions of the weak interactions to the atomic level energies are some 50 times larger than in the Cs atom. We report the results of laser spectroscopy experiments on Ra-209-214(+) isotopes in preparation of a precision atomic parity violation experiment. Expe

  15. Ionizable (Thia)calix[4]crowns as Highly Selective 226Ra2+ Ionophores

    NARCIS (Netherlands)

    Leeuwen, van Fijs W.B.; Beijleveld, Hans; Miermans, Cornelis J.H.; Huskens, Jurriaan; Verboom, Willem; Reinhoudt, David N.

    2005-01-01

    The 226Ra2+ selectivity of the ionizable (thia)calix[4]crowns 1-4 was determined in the presence of a large excess of the most common alkali and alkaline earth cations. Selective 226Ra2+ (2.9 × 10-8 M) extraction occurs even at extremely high Mn+/226Ra2+ ratios of 3.5 × 107 [Mn+ = Na+, K+, Rb+, Cs+,

  16. Ra-228, Ra-226 and Ra-228/Ra-226 Activity Ratio in the Northern South China Sea

    Science.gov (United States)

    Yu-Chia, C.

    2004-05-01

    We report for the first time the surface water distributions of Ra-228 and Ra-226 in the northern South China Sea (SCS) and vertical profiles in the central deep basin of the SCS. Being a marginal sea, the SCS displays activities of both nuclides much higher than the open oceans. The surface water Ra-228 varies between 22 and 33 dpm/100L with higher values at stations adjacent to the landmass. The surface water Ra-226 varies from 10 to 15 dpm/100L with a distribution pattern similar to that of Ra-228. The Ra-228/Ra-226 activity ratio is fairly constant at about 2 or slightly higher. Ra-228 decreases rapidly from a surface maximum of about 22 dpm/100L to about 12 dpm/100L at and below 300m depth in the deep central basin. The deep water values are much higher than those of the open oceans. Ra-226, on the other hand, shows a surface activity of 14 dpm/100L, decreases to 10 dpm/100L at 200m, and then increases monotonically with depth to about 35 dpm/100L at and below 3000m. This distribution pattern is similar to that observed in the western North Pacific but the activity is higher by about 5 dpm/100L for the entire water column. The resulting Ra-228/Ra-226 is greater than one above 250m and becomes less than one below this depth with the ratio decreasing to about 0.35 in the deep water below 3000m. This ratio remains much greater than that in the open oceans, implying a strong Ra-228 input relative to Ra-226 into the SCS deep water.

  17. Effect of Wood Aging on Wine Mineral Composition and (87)Sr/(86)Sr Isotopic Ratio.

    Science.gov (United States)

    Kaya, Ayse D; Bruno de Sousa, Raúl; Curvelo-Garcia, António S; Ricardo-da-Silva, Jorge M; Catarino, Sofia

    2017-06-14

    The evolution of mineral composition and wine strontium isotopic ratio (87)Sr/(86)Sr (Sr IR) during wood aging were investigated. A red wine was aged in stainless steel tanks with French oak staves (Quercus sessiliflora Salisb.), with three industrial scale replicates. Sampling was carried out after 30, 60, and 90 days of aging, and the wines were evaluated in terms of general analysis, phenolic composition, total polysaccharides, multielement composition, and Sr IR. Li, Be, Mg, Al, Sc, Ti, V, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Rb, Sr, Y, Zr, Mo, Sb, Cs, Ba, Pr, Nd, Sm, Eu, Dy, Ho, Er, Yb, Lu, Tl, and Pb elements and (87)Sr/(86)Sr were determined by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and Na, K, Ca, and Fe by flame atomic absorption spectrometry (FAAS). Two-way ANOVA was applied to assess wood aging and time effect on Sr IR and mineral composition. Wood aging resulted in significantly higher concentrations of Mg, V, Co, Ni, and Sr. At the end of the aging period, wine exhibited statistically identical Sr IR compared to control. Study suggests that wood aging does not affect (87)Sr/(86)Sr, not precluding the use of this parameter for wine traceability purposes.

  18. Improving CS regulations.

    Energy Technology Data Exchange (ETDEWEB)

    Nesse, R.J.; Scheer, R.M.; Marasco, A.L.; Furey, R.

    1980-10-01

    President Carter issued Executive Order 12044 (3/28/78) that required all Federal agencies to distinguish between significant and insignificant regulations, and to determine whether a regulation will result in major impacts. This study gathered information on the impact of the order and the guidelines on the Office of Conservation and Solar Energy (CS) regulatory practices, investigated problems encountered by the CS staff when implementing the order and guidelines, and recommended solutions to resolve these problems. Major tasks accomplished and discussed are: (1) legislation, Executive Orders, and DOE Memoranda concerning Federal administrative procedures relevant to the development and analysis of regulations within CS reviewed; (2) relevant DOE Orders and Memoranda analyzed and key DOE and CS staff interviewed in order to accurately describe the current CS regulatory process; (3) DOE staff from the Office of the General Counsel, the Office of Policy and Evaluation, the Office of the Environment, and the Office of the Secretary interviewed to explore issues and problems encountered with current CS regulatory practices; (4) the regulatory processes at five other Federal agencies reviewed in order to see how other agencies have approached the regulatory process, dealt with specific regulatory problems, and responded to the Executive Order; and (5) based on the results of the preceding four tasks, recommendations for potential solutions to the CS regulatory problems developed. (MCW)

  19. Understanding Rheumatoid Arthritis (RA): Research

    Science.gov (United States)

    ... page please turn JavaScript on. Feature: Understanding Rheumatoid Arthritis (RA) Research Past Issues / Summer 2014 Table of ... project plan to address relevant challenges for rheumatoid arthritis. Read Part 1 on Lupus in MedlinePlus magazine, ...

  20. Rapid determination of 226Ra in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, Sherrod L.; Culligan, Brian K.

    2012-02-04

    A new rapid method for the determination of {sup 228}Ra in natural water samples has been developed at the SRNL/EBL (Savannah River National Lab/ Environmental Bioassay Laboratory) that can be used for emergency response or routine samples. While gamma spectrometry can be employed with sufficient detection limits to determine {sup 228}Ra in solid samples (via {sup 228}Ac) , radiochemical methods that employ gas flow proportional counting techniques typically provide lower MDA (Minimal Detectable Activity) levels for the determination of {sup 228}Ra in water samples. Most radiochemical methods for {sup 228}Ra collect and purify {sup 228}Ra and allow for {sup 228}Ac daughter ingrowth for ~36 hours. In this new SRNL/EBL approach, {sup 228}Ac is collected and purified from the water sample without waiting to eliminate this delay. The sample preparation requires only about 4 hours so that {sup 228}Ra assay results on water samples can be achieved in < 6 hours. The method uses a rapid calcium carbonate precipitation enhanced with a small amount of phosphate added to enhance chemical yields (typically >90%), followed by rapid cation exchange removal of calcium. Lead, bismuth, uranium, thorium and protactinium isotopes are also removed by the cation exchange separation. {sup 228}Ac is eluted from the cation resin directly onto a DGA Resin cartridge attached to the bottom of the cation column to purify {sup 228}Ac. DGA Resin also removes lead and bismuth isotopes, along with Sr isotopes and {sup 90}Y. La is used to determine {sup 228}Ac chemical yield via ICP-MS, but {sup 133}Ba can also be used instead if ICP-MS assay is not available. Unlike some older methods, no lead or strontium holdback carriers or continual readjustment of sample pH is required.

  1. Frameworks in CS1

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak; Caspersen, Michael Edelgaard

    2002-01-01

    In this paper we argue that introducing object-oriented frameworks as subject already in the CS1 curriculum is important if we are to train the programmers of tomorrow to become just as much software reusers as software producers. We present a simple, graphical, framework that we have successfully...

  2. Leaching Rate Test of Nuclei Cs and Sr

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A novel material-resemble verifiable cement for disposal of spent nuclear fuel reprocessing mediate-level waste has been developed. Waste form has been characterized for their compressive strength, phase composition. The cement formulation has been patented. In this experiment, the cement was mixed with simulated wastes for each composition 5 min at least. Ratio of waste to the cement is 0.45-0.55. After being packed into cylindrical molds, the grouts were cured for a period 28 days in a room temperature curing chamber at atmospheric pressure. The wasteform then

  3. VeVeRa-IV

    NARCIS (Netherlands)

    Evelien Eggink; Debbie Oudijk; Klarita Sadiraj

    2012-01-01

    Original title: VeVeRa-IV The Dutch population is set to age rapidly in the coming years. More and more people will also attain a very great age. This means that the need for home care and care provided in nursing or residential care homes will also increase. As part of the Long-term Care Programme

  4. RAPID DETERMINATION OF RA-226 IN ENVIRONMENTAL SAMPLES

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, S.

    2012-01-03

    A new rapid method for the determination of {sup 226}Ra in environmental samples has been developed at the Savannah River Site Environmental Lab (Aiken, SC, USA) that can be used for emergency response or routine sample analyses. The need for rapid analyses in the event of a Radiological Dispersive Device or Improvised Nuclear Device event is well-known. In addition, the recent accident at Fukushima Nuclear Power Plant in March, 2011 reinforces the need to have rapid analyses for radionuclides in environmental samples in the event of a nuclear accident. {sup 226}Ra (T1/2 = 1,620 years) is one of the most toxic of the long-lived alpha-emitters present in the environment due to its long life and its tendency to concentrate in bones, which increases the internal radiation dose of individuals. The new method to determine {sup 226}Ra in environmental samples utilizes a rapid sodium hydroxide fusion method for solid samples, calcium carbonate precipitation to preconcentrate Ra, and rapid column separation steps to remove interferences. The column separation process uses cation exchange resin to remove large amounts of calcium, Sr Resin to remove barium and Ln Resin as a final purification step to remove {sup 225}Ac and potential interferences. The purified {sup 226}Ra sample test sources are prepared using barium sulfate microprecipitation in the presence of isopropanol for counting by alpha spectrometry. The method showed good chemical recoveries and effective removal of interferences. The determination of {sup 226}Ra in environmental samples can be performed in less than 16 h for vegetation, concrete, brick, soil, and air filter samples with excellent quality for emergency or routine analyses. The sample preparation work takes less than 6 h. {sup 225}Ra (T1/2 = 14.9 day) tracer is used and the {sup 225}Ra progeny {sup 217}At is used to determine chemical yield via alpha spectrometry. The rapid fusion technique is a rugged sample digestion method that ensures that any

  5. CsMgCl{sub 3}: A promising cross luminescence material

    Energy Technology Data Exchange (ETDEWEB)

    Shwetha, G. [Department of Physics, Indian Institute of Technology Hyderabad, Ordnance Factory Estate, Yeddumailaram 502 205, Telangana (India); Kanchana, V., E-mail: kanchana@iith.ac.in [Department of Physics, Indian Institute of Technology Hyderabad, Ordnance Factory Estate, Yeddumailaram 502 205, Telangana (India); Vaitheeswaran, G. [Advanced Center of Research in High Energy Materials (ACRHEM), University of Hyderabad, Prof. C. R. Rao Road, Gachibowli, Hyderabad 500 046, Telangana (India)

    2015-07-15

    Full-potential linearized augmented plane wave method has been used to study the cross luminescence of halide scintillators. The electronic structure and optical properties of alkali halides such as CsMgCl{sub 3}, CsCaCl{sub 3}, and CsSrCl{sub 3} are presented. One of the major criteria for the cross luminescence to happen is the energy difference between valence band and next deeper core valence band being lesser when compared to energy gap of the compound, so that radiative electronic transition may occur between core valence band and valence band which might lead to fast scintillation. We found this criterion to be satisfied in these compounds leading to cross luminescence. The presence of high energy peaks in the absorption spectra indicates the creation of holes in the core valence band, which is an essential criterion for the occurrence of cross luminescence. The electronic structure, and optical properties studies clearly indicate CsMgCl{sub 3}, CsCaCl{sub 3}, and CsSrCl{sub 3} to be cross luminescence materials comparable to CsCl which is one of the well known fast scintillators. In addition, CsMgCl{sub 3} is found to be better among the studied compounds with optical isotropy though the compound is structurally anisotropic. - Graphical abstract: Absorption spectra of CsMCl{sub 3} (M=Mg, Ca, and Sr) along with CsCl, indicating both the spectra are similar in the lower energy region. - Highlights: • These are cross valence luminescence (CVL) materials with short day time of the order of nanosecond. • Chemical bonding of these compounds studied observed the ionic nature. • These are fast scintillators comparable to their binary halide. • CsMgCl{sub 3} good scintillator with optically isotropic nature.

  6. Geological and physicochemical controls of the spatial distribution of partition coefficients for radionuclides (Sr-90, Cs-137, Co-60, Pu-239,240 and Am-241) at a site of nuclear reactors and radioactive waste disposal (St. Petersburg region, Russian Federation).

    Science.gov (United States)

    Rumynin, Vyacheslav G; Nikulenkov, Anton M

    2016-10-01

    The paper presents a study of the sorption properties of sediments of different geological ages and lithological types, governing radionuclide retention in the subsurface (up to 160 m beneath the surface) within the area of potential influence of the Northwestern Center of Atomic Energy (NWCAE), St. Petersburg region, RF. The focus of this work is mostly on the sedimentary rocks of two types, i.e., weakly cemented sandstone and lithified clay formations of Cambrian and Vendian series. The first lithological unit is associated with a groundwater reservoir (Lomonosov aquifer), and the second one, with both a relative aquitard in the upper part of the Vendian formation (Kotlin clay) and a regional aquifer (Gdov aquifer) in the lower part of the formation. The main mechanisms responsible for the variability of the sorption distribution coefficient (Kd, defined as the ratio of the concentration of solute on solid phase to its concentration in solution at equilibrium) was identified for radionuclides such as Sr-90, Cs-137, Co-60, Pu-239,240, and Am-241. It was shown that the main factors contributing to the chemical heterogeneity of the Cambrian sandstone were related to the presence of secondary minerals (iron and magnesium oxides and hydroxides produced by the weathering process) in trace amounts, forming correlated layer structures. The statistical analysis of nonlinear isotherms confirmed this conclusion. For the Vendian formation, a determinate trend was established in the Kd change over depth as a result of temporal trends in the sedimentation process and pore-water chemistry. The geostatistical characteristics and the spatial correlation models for describing linear sorption of different radionuclides are not identical, and the exhibition of chemical heterogeneity of sedimentary rock of a particular lithological type depends on radionuclide chemistry. Moreover, variogram analysis for some Kd data sets (both in Cambrian and Vendian formations) demonstrates the

  7. Molecular CsF 5 and CsF 2 +

    KAUST Repository

    Rogachev, Andrey Yu.

    2015-06-03

    D5h star-like CsF5, formally isoelectronic with known XeF5− ion, is computed to be a local minimum on the potential energy surface of CsF5, surrounded by reasonably large activation energies for its exothermic decomposition to CsF+2 F2, or to CsF3 (three isomeric forms)+F2, or for rearrangement to a significantly more stable isomer, a classical Cs+ complex of F5−. Similarly the CsF2+ ion is computed to be metastable in two isomeric forms. In the more symmetrical structures of these molecules there is definite involvement in bonding of the formally core 5p levels of Cs.

  8. Frameworks in CS1

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak; Caspersen, Michael Edelgaard

    2002-01-01

    point for introducing graphical user interface frameworks such as Java Swing and AWT as the students are not overwhelmed by all the details of such frameworks right away but given a conceptual road-map and practical experience that allow them to cope with the complexity.......In this paper we argue that introducing object-oriented frameworks as subject already in the CS1 curriculum is important if we are to train the programmers of tomorrow to become just as much software reusers as software producers. We present a simple, graphical, framework that we have successfully...

  9. Compilation of Spectroscopic Data of Radium (Ra I and Ra II)

    NARCIS (Netherlands)

    Dammalapati, U.; Jungmann, K.; Willmann, L.

    2016-01-01

    Energy levels, wavelengths, lifetimes, and hyperfine structure constants for the isotopes of the first and second spectra of radium, Ra I and Ra II, have been compiled. Wavelengths and wavenumbers are tabulated for 226Ra and for other Ra isotopes. Isotope shifts and hyperfine structure constants of

  10. Compilation of spectroscopic data of Radium (Ra I and Ra II)

    CERN Document Server

    Dammalapati, U; Willmann, L

    2016-01-01

    Energy levels, wavelengths, lifetimes and hyperfine structure constants for the isotopes of the first and second spectra of radium, Ra I and Ra II have been compiled. Wavelengths and wave numbers are tabulated for 226Ra and for other Ra isotopes. Isotope shifts and hyperfine structure constants of even and odd-A isotopes of neutral radium atom and singly ionized radium are included. Experimental lifetimes of the states for both neutral and ionic Ra are also added, where available. The information is beneficial for present and future experiments aimed at different physics motivations using neutral Ra and singly ionized Ra.

  11. VELoCiRaPTORS.

    Science.gov (United States)

    Lundgren, J.; Esham, B.; Padalino, S. J.; Sangster, T. C.; Glebov, V.

    2007-11-01

    The Venting and Exhausting of Low Level Air Contaminants in the Rapid Pneumatic Transport of Radioactive Samples (VELoCiRaPTORS) system is constructed to transport radioactive materials quickly and safely at the NIF. A radioactive sample will be placed inside a carrier that is transported via an airflow system produced by controlled differential pressure. Midway through the transportation process, the carrier will be stopped and vented by a powered exhaust blower which will remove radioactive gases within the transport carrier. A Geiger counter will monitor the activity of the exhaust gas to ensure that it is below acceptable levels. If the radiation level is sufficient, the carrier will pass through the remainder of the system, pneumatically braking at the counting station. The complete design will run manually or automatically with control software. Tests were performed using an inactive carrier to determine possible transportation problems. The system underwent many consecutive trials without failure. VELoCiRaPTORS is a prototype of a system that could be installed at both the Laboratory for Laser Energetics at the University of Rochester and the National Ignition Facility at LLNL.

  12. Foundation Fireworks CS4

    CERN Document Server

    Smith, N; Heerema, Matt; Mallott, Chuch; King, R; Erskine, Craig

    2009-01-01

    Are you a web designer who is looking for a new and quicker way to prototype and create for the web? Perhaps you are a programmer who finds most design tools to be overkill for what you need to get done. Or, maybe you're an old Fireworks pro, who wants to keep up to date on the latest changes in Creative Suite 4. Either way, this book has something for you. * Coverage of all that's new and powerful for the Web designer and developer in Fireworks CS4* Targets developers who want design tools that don't get in their way and designers who want development tools that don't constrain their creativi

  13. Emergence of Bulk CsCl Structure in $(CsCl)_{n}Cs^{+}$ Cluster Ions

    CERN Document Server

    Aguado, A

    2000-01-01

    The emergence of CsCl bulk structure in (CsCl)nCs+ cluster ions is investigated using a mixed quantum-mechanical/semiempirical theoretical approach. We find that rhombic dodecahedral fragments (with bulk CsCl symmetry) are more stable than rock-salt fragments after the completion of the fifth rhombic dodecahedral atomic shell. From this size (n=184) on, a new set of magic numbers should appear in the experimental mass spectra. We also propose another experimental test for this transition, which explicitely involves the electronic structure of the cluster. Finally, we perform more detailed calculations in the size range n=31--33, where recent experimental investigations have found indications of the presence of rhombic dodecahedral (CsCl)32Cs+ isomers in the cluster beams.

  14. LCA versus RA - an introduction

    DEFF Research Database (Denmark)

    Olsen, Stig Irving

    2000-01-01

    Risk Assessment (RA) of chemicals is an environmental management tool used to assess the risk of specific chemicals, which are harmful to man or the environment under certain circumstances of use or in certain environmental recipients. Life Cycle Assessment (LCA) or environmental assessment...... of products is another environmental management tool that gains more and more ground, and which is often thought of as universal due to its basic holistic philosophy. As the environmental impacts of one product can only be seen in relation to the impacts of other products providing the same functions, LCA...... is a comparative tool. The primary purpose of this article is to identify harmonies, discrepancies and relations between the two tools, exemplified by the risk assessment principles of the European Commission (EC) as stated in 'Technical Guidance Document' (EC, 1996) and the LCA method 'EDIP' (Environmental Design...

  15. Računalom potpomognute tehnike revizije

    OpenAIRE

    2008-01-01

    Namjera ovoga rada je ukazati na mogućnosti učinkovitijeg revidiranja u okruženju sve intenzivnijega korištenja računalnih tehnika koje pomažu reviziji CAAT, jer sveukupni ciljevi i opseg revizije ne mijenjaju se kada se revizija obavlja u računalno-informatičkom okruženju. CAATs mogu poboljšati učinkovitost i produktivnost revizijskih procedura. Računalom potpomognute tehnike revizije (CAATs) jesu načini na koje, u kompjuteriziranom sustavu informacija, revizor može koristiti rač...

  16. Structure of a highly acidic β-lactamase from the moderate halophile Chromohalobacter sp. 560 and the discovery of a Cs{sup +}-selective binding site

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Shigeki; Yonezawa, Yasushi; Okazaki, Nobuo; Matsumoto, Fumiko; Shibazaki, Chie; Shimizu, Rumi; Yamada, Mitsugu; Adachi, Motoyasu; Tamada, Taro [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Ibaraki 319-1195 (Japan); Kawamoto, Masahide [Kyushu Synchrotron Light Research Center, 8-7 Yayoigaoka, Tosu, Saga 841-0005 (Japan); Tokunaga, Hiroko; Ishibashi, Matsujiro [Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065 (Japan); Blaber, Michael [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Ibaraki 319-1195 (Japan); Florida State University, 1115 West Call Street, Tallahassee, FL 32306-4300 (United States); Tokunaga, Masao [Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065 (Japan); Kuroki, Ryota, E-mail: kuroki.ryota@jaea.go.jp [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Ibaraki 319-1195 (Japan)

    2015-03-01

    The tertiary structure of a β-lactamase derived from the halobacterium Chromohalobacter sp. 560 (HaBLA) was determined by X-ray crystallography. Three unique Sr{sup 2+}-binding sites and one Cs{sup +}-binding site were discovered in the HaBLA molecule. Environmentally friendly absorbents are needed for Sr{sup 2+} and Cs{sup +}, as the removal of the radioactive Sr{sup 2+} and Cs{sup +} that has leaked from the Fukushima Nuclear Power Plant is one of the most important problems in Japan. Halophilic proteins are known to have many acidic residues on their surface that can provide specific binding sites for metal ions such as Cs{sup +} or Sr{sup 2+}. The crystal structure of a halophilic β-lactamase from Chromohalobacter sp. 560 (HaBLA) was determined to resolutions of between 1.8 and 2.9 Å in space group P3{sub 1} using X-ray crystallography. Moreover, the locations of bound Sr{sup 2+} and Cs{sup +} ions were identified by anomalous X-ray diffraction. The location of one Cs{sup +}-specific binding site was identified in HaBLA even in the presence of a ninefold molar excess of Na{sup +} (90 mM Na{sup +}/10 mM Cs{sup +}). From an activity assay using isothermal titration calorimetry, the bound Sr{sup 2+} and Cs{sup +} ions do not significantly affect the enzymatic function of HaBLA. The observation of a selective and high-affinity Cs{sup +}-binding site provides important information that is useful for the design of artificial Cs{sup +}-binding sites that may be useful in the bioremediation of radioactive isotopes.

  17. Dreamweaver CS5 digital classroom

    CERN Document Server

    Osborn, Jeremy; Heald, Greg

    2013-01-01

    Learning Dreamweaver is a dream with this instructional book-and-video training package! Dreamweaver CS5 Digital Classroom covers Dreamweaver CS5 and Dreamweaver CS5.5. Adobe Dreamweaver allows you to easily create robust Web sites without needing extensive programming knowledge or skills. The latest version of Dreamweaver boasts enhanced capabilities and this exciting book-and-downloadable video training package makes learning the new features of Dreamweaver less intimidating. Sixteen self-paced lessons explain how to design, develop, and maintain a fully functioning si

  18. Classifying Finitely Generated Indecomposable RA Loops

    CERN Document Server

    Cornelissen, Mariana

    2012-01-01

    In 1995, E. Jespers, G. Leal and C. Polcino Milies classified all finite ring alternative loops (RA loops for short) which are not direct products of proper subloops. In this paper we extend this result to finitely generated RA loops and provide an explicit description of all such loops.

  19. Cardiovascular risk factor management in patients with RA compared to matched non-RA patients

    NARCIS (Netherlands)

    E. Alemao (Evo); H. Cawston (Helene); F. Bourhis (Francois); M.J. Al (Maiwenn); M.P.M.H. Rutten-van Mölken (Maureen); K. Liao (Katherine); D.H. Solomon (Daniel)

    2015-01-01

    markdownabstractObjective. RA is associated with a 50-60% increase in risk of cardiovascular (CV) death. This study aimed to compare management of CV risk factors in RA and matched non-RA patients. Methods. A retrospective cohort study was conducted using UK clinical practice data. Patients presen

  20. Learning Flash CS4 Professional

    CERN Document Server

    Shupe, Rich

    2009-01-01

    Learning Flash CS4 Professional offers beginners and intermediate Flash developers a unique introduction to the latest version of Adobe's powerful multimedia application. This easy-to-read book is loaded with full-color examples and hands-on tasks to help you master Flash CS4's new motion editor, integrated 3D system, and character control using the new inverse kinematics bones animation system. No previous Flash experience is necessary.

  1. A role for the high-density lipoprotein receptor SR-B1 in synovial inflammation via serum amyloid-A.

    LENUS (Irish Health Repository)

    Mullan, Ronan Hugh

    2012-02-01

    Acute phase apoprotein Serum Amyloid A (A-SAA), which is strongly expressed in rheumatoid arthritis synovial membrane (RA SM), induces angiogenesis, adhesion molecule expression, and matrix metalloproteinase production through the G-coupled receptor FPRL-1. Here we report alternative signaling through the high-density lipoprotein receptor scavenger receptor-class B type 1 (SR-B1). Quantitative expression\\/localization of SR-B1 in RA SM, RA fibroblast-like cells (FLCs), and microvascular endothelial cells (ECs) was assessed by Western blotting and immunohistology\\/fluorescence. A-SAA-mediated effects were examined using a specific antibody against SR-B1 or amphipathic alpha-Helical Peptides (the SR-B1 antagonists L-37pA and D-37pA), in RA FLCs and ECs. Adhesion molecule expression and cytokine production were quantified using flow cytometry and ELISA. SR-B1 was strongly expressed in the RA SM lining layer and endothelial\\/perivascular regions compared with osteoarthritis SM or normal control synovium. Differential SR-B1 expression in RA FLC lines (n = 5) and ECs correlated closely with A-SAA, but not tumor necrosis factor alpha-induced intercellular adhesion molecule-1 upregulation. A-SAA-induced interleukin-6 and -8 production was inhibited in the presence of anti-SR-B1 in human microvascular endothelial cells and RA FLCs. Moreover, D-37pA and L-37pA inhibited A-SAA-induced vascular cell adhesion molecule-1 and intercellular adhesion molecule expression from ECs in a dose-dependent manner. As SR-B1 is expressed in RA synovial tissue and mediates A-SAA-induced pro-inflammatory pathways, a better understanding of A-SAA-mediated inflammatory pathways may lead to novel treatment strategies for RA.

  2. 226Ra and 228Ra in the Seawater of the Western Yellow Sea

    Institute of Scientific and Technical Information of China (English)

    MEN Wu; WEI Hao; LIU Guangshan

    2006-01-01

    Radium isotopes 226Ra and 228Ra in seawater of the western Yellow Sea were measured by using the Mn-fiber adsorption- HPGe γ spectrum method.The distribution features of the two isotopes have been studied.The activities of 226Ra and 228Ra are 2.72-5.57 Bq m-3 and 7.51-34.3 Bq m-3, respectively.The activities of 226Ra and 228Ra from surface to bottom for each depth profile station are comparable within the experimental error, but the mean activities decrease with distance from the shore.From the distribution data of 228Ra, the horizontal eddy diffusion coefficient was estimated at 29 × 106 cm2 s 1.

  3. Cardiovascular risk factor management in patients with RA compared to matched non-RA patients

    Science.gov (United States)

    Cawston, Helene; Bourhis, Francois; Al, Maiwenn; Rutten-van Mölken, Maureen P. M. H.; Liao, Katherine P.; Solomon, Daniel H.

    2016-01-01

    Objective. RA is associated with a 50–60% increase in risk of cardiovascular (CV) death. This study aimed to compare management of CV risk factors in RA and matched non-RA patients. Methods. A retrospective cohort study was conducted using UK clinical practice data. Patients presenting with an incident RA diagnosis were matched 1:4 to non-RA patients based on a propensity score for RA, entry year, CV risk category and treatment received at index date (date of RA diagnosis). Patients tested and treated for CV risk factors as well as those attaining CV risk factor management goals were evaluated in both groups. Results. Between 1987 and 2010, 24 859 RA patients were identified and matched to 87 304 non-RA patients. At index date, groups had similar baseline characteristics. Annual blood pressure, lipids and diabetes-related testing were similar in both groups, although CRP and ESR were higher in RA patients at diagnosis and decreased over time. RA patients prescribed antihypertensives increased from 38.2% at diagnosis to 45.7% at 5 years, from 14.0 to 20.6% for lipid-lowering treatments and from 5.1 to 6.4% for antidiabetics. Similar treatment percentages were observed in non-RA patients, although slightly lower for antihypertensives. Modest (2%) but significantly lower attainment of lipid and diabetes goals at 1 year was observed in RA patients. Conclusion. There were no differences between groups in the frequency of testing and treatment of CV risk factors. Higher CV risk in RA patients seems unlikely to be driven by differences in traditional CV risk factor management. PMID:26705329

  4. Data and uncertainty assessment for radionuclide K{sub d} partitioning coefficients in granitic rock for use in SR-Can calculations

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, James; Neretnieks, Ivars; Malmstroem, Maria [Royal Inst. of Technology, Stockholm (Sweden). Dept. of Chemical Engineering and Technology

    2006-10-15

    SKB is currently preparing licence applications related to the proposed deep repository for spent nuclear fuel as well as the encapsulation plant required for canister fabrication. The present report is one of several specific data reports that form the data input to an interim safety report (SR-Can) for the encapsulation plant licence application. This report concerns the derivation and recommendation of generic K{sub d} data (i.e. linear partitioning coefficients) for safety assessment modelling of far-field radionuclide transport in fractured granitic rock. The data are derived for typical Swedish groundwater conditions and rock types distinctive of those found on the Simpevarp peninsula and Forsmark. Data have been derived for 8 main elements (Cs, Sr, Ra, Ni, Th, U, Np, Am) and various oxidation states. The data have also been supplied with tentative correction factors to account for artefacts that have not been previously considered in detail in previous compilations. For the main reviewed solutes the data are given in terms of a best estimate K{sub d} value assumed to be the median of the aggregate set of selected data. A range corresponding to the 25-75% inter-quartile range is also specified and probable ranges of uncertainty are estimated in the form of an upper and lower limit to the expected variability. Data for an additional 19 elements that have not been reviewed are taken from a previous compilation by Carbol and Engkvist.

  5. Free enthalpy landscape of SrO.

    Science.gov (United States)

    Schön, J C; Cancarević, Z P; Hannemann, A; Jansen, M

    2008-05-21

    Trying to predict thermodynamically stable and metastable solid compounds as function of pressure and temperature requires the global exploration of the enthalpy landscapes of chemical systems and the subsequent construction of their free enthalpy landscapes. In this work, we present a general approach to the determination of a free energy landscape. As an example, we construct the free enthalpy landscape of SrO for two different pressures on the empirical potential level and also compute various thermodynamic and elastic properties of SrO in the NaCl-, CsCl-, NiAs-, NbS-, TiP-, beta-BeO, sphalerite-, and wurtzite-structure type on an ab initio level. We employ density functional theory within the hybrid B3LYP approximation. The results show good agreement with experimental and theoretical data.

  6. Understanding Rheumatoid Arthritis (RA): Treatment and Causes

    Science.gov (United States)

    ... this page please turn JavaScript on. Feature: Understanding Rheumatoid Arthritis (RA) Treatment and Causes Past Issues / Summer 2014 Table of Contents How Is Rheumatoid Arthritis Treated? Doctors have many ways to treat this ...

  7. RA Construction KC, LLC Information Sheet

    Science.gov (United States)

    RA Construction KC, LLC (the Company) is located in Gladstone, Missouri. The settlement involves renovation activities conducted at a property constructed prior to 1978, located in Kansas City, Missouri.

  8. 226Ra or 226Ra/Ba dating of Holocene volcanic rocks: application to Mt. Etna and Merapi volcanoes

    Science.gov (United States)

    Condomines, M.; Gauthier, P. J.; Tanguy, J. C.; Gertisser, R.; Thouret, J. C.; Berthommier, P.; Camus, G.

    2005-02-01

    This paper shows how 226Ra- 230Th disequilibria can be used to date Holocene volcanic rocks from some well selected volcanoes. A systematic study of these disequilibria on historical or well-dated volcanic samples is indeed first required to test the applicability of this method. Two examples are described here to illustrate its potential. In the case of Mt. Etna, the good correlation observed between ( 226Ra) 0 activities at the time of eruption and Th contents in lava flows from the last two millennia [M. Condomines, J.C. Tanguy, V. Michaud, Magma dynamics at Mt. Etna: constraints from U-Th-Ra-Pb radioactive disequilibria and Sr isotopes in historical lavas, Earth Planet. Sci. Lett. 132 (1995) 25-41] is used to infer the ages of several newly analysed lava flows. The calculated ages are in good agreement with those deduced from the archaeomagnetic curve describing the variation of the geomagnetic field direction in southern Italy [J.C. Tanguy, I. Bucur, J.F.C. Thompson, Geomagnetic secular variation in Sicily and revised ages of historic lavas from Mt. Etna, Nature 318 (1985) 453-455, J.C. Tanguy, M. Le Goff, V. Chillemi, A. Paiotti, C. Principe, S. La Delfa, G. Patane, Variation séculaire de la direction du champ géomagnétique enregistrée par les laves de l'Etna et du Vésuve pendant les deux derniers millénaires, C. R. Acad. Sci. Paris 329 (1999) 557-564, J.C. Tanguy, M. Le Goff, C. Principe, S. Arrighi, V. Chillemi, A. Paiotti, S. La Delfa, G. Patane, Archaeomagnetic dating of Mediterranean volcanics of the last 2100 years: validity and limits. Earth Planet. Sci. Lett. 211 (2003) 111-124]. We also present a whole set of new U-series data on historical, recent, and older samples from Merapi (Indonesia), and show that the ( 226Ra)/Ba ratio has probably maintained a quasi-steady state value during at least the past four millennia, and can be used to infer the ( 226Ra) 0/Ba ratio of old volcanics at the time of eruption, and thus their ages. Comparison with

  9. Leaching behaviour of and Cs disposition in a UMo powellite glass–ceramic

    Energy Technology Data Exchange (ETDEWEB)

    Vance, E.R., E-mail: erv@ansto.gov.au [Institute of Materials Engineering, ANSTO, Kirrawee DC, NSW 2232 (Australia); Davis, J.; Olufson, K.; Gregg, D.J.; Blackford, M.G.; Griffiths, G.R. [Institute of Materials Engineering, ANSTO, Kirrawee DC, NSW 2232 (Australia); Farnan, I. [Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ (United Kingdom); Sullivan, J.; Sprouster, D.; Campbell, C.; Hughes, J. [Centre for Antimatter-Matter Studies (CAMS), Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia)

    2014-05-01

    A UMo powellite glass–ceramic designed by French workers to immobilise Mo-rich intermediate-level waste was found to be quite leach resistant in water at 90 °C with the dissolution of Cs, Mo, Na, B and Ca not exceeding 2 g/L in normalised PCT tests. {sup 133}Cs solid state nuclear magnetic resonance and scanning electron microscopy (SEM) showed the Cs to inhabit the glass phase. The microstructures were not greatly affected by cooling rates between 1 and 5 °C/min or by introducing 10 times as much Cs and Sr. Protracted leach tests at 90 °C showed surface alteration as evidenced by SEM and particularly transmission electron microscopy; the main alteration phase was a Zn aluminosilicate but several other alteration phases were evident. Voidage in the alteration layers was indicated from enhanced lifetimes in positron annihilation lifetime spectroscopy.

  10. Status of the HMPID CsI-RICH project for ALICE at the CERN/LHC

    CERN Document Server

    Di Mauro, Antonello; Belin, B; Braem, André; Chileev, K; Davenport, M; De Cataldo, G; Di Bari, D; Franco, A; Fratino, U; Gallas, A; Guber, F; Hoedlmoser, H; Kurepin, A B; Martinengo, P; Nappi, E; Paic, G; Pastore, C; Piuz, François; Santiard, Jean-Claude; Schyns, E; Sgura, I; Tauro, A

    2005-01-01

    The ALICE (A Large Ion Collider Experiment) high momentum particle identification (HMPID) detector, presently under construction, consists of seven identical proximity focusing ring imaging Cherenkov (RICH) counters exploiting large area CsI photocathodes for Cherenkov light imaging. With a total area of 11 m/sup 2/, it represents the largest CsI-RICH system ever used in High Energy Physics. The detector layout, assembly and quality checks will be presented, with particular emphasis on CsI photocathodes mass production. A validation procedure has been established combining the results of the photocathode response mapping obtained in a dedicated VUV scanner with test beam data. The long-term stability has also been studied by irradiation with a Sr-90 source of a final size CsI photocathode inside a detector prototype.

  11. Determination of (137)Cs half-life with an ionization chamber.

    Science.gov (United States)

    Juget, Frédéric; Nedjadi, Youcef; Buchillier, Thierry; Bochud, François; Bailat, Claude

    2016-12-01

    The half-life of (137)Cs was measured with an ionization chamber by following the decay of 5 sources over a 30 years period between 1983 and 2013. The ratio between the ionization chamber current for the cesium sources and (226)Ra source was used for the half-life calculation. The value found for the (137)Cs half-life is 10,955.2±10.7 days, where the uncertainty evaluation combines type A and B for one standard deviation.

  12. Adobe发布Photoshop CS6 Beta

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Adobe发布Photoshop CS6Beta。Photoshop CS6Beta包含PhotoshopCS6及Photoshop CS6 Extended中的所有功能(正式版dPCS6将不包含CS6Extended中的功能),用户可以免费体验3D影像编辑及图像分析功能。

  13. Removal of 226Ra and 228Ra from TENORM sludge waste using surfactants solutions.

    Science.gov (United States)

    Attallah, M F; Hamed, Mostafa M; El Afifi, E M; Aly, H F

    2015-01-01

    The feasibility of using surfactants as extracting agent for the removal of radium species from TENORM sludge produced from petroleum industry is evaluated. In this investigation cationic and nonionic surfactants were used as extracting agents for the removal of radium radionuclides from the sludge waste. Two surfactants namely cetyltrimethylammonium bromide (CTAB) and Triton X-100 (TX100) were investigated as the extracting agents. Different parameters affecting the removal of both (226)Ra and (228)Ra by the two surfactants as well as their admixture were studied by the batch technique. These parameters include effect of shaking time, surfactants concentration and temperature as well as the effect of surfactants admixture. It was found that, higher solution temperature improves the removal efficiency of radium species. Combined extraction of nonionic and cationic surfactants produces synergistic effect in removal both (226)Ra and (228)Ra, where the removals reached 84% and 80% for (226)Ra and (228)Ra, respectively, were obtained using surfactants admixture.

  14. Determination of {sup 226}Ra and {sup 228}Ra in water by using liquid scintillation spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mingote, Raquel Maia; Gomes, Nilton Carlos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Servico de Quimica e Radioquimica], E-mail: mingote@cdtn.br; Gomes, Lorena Pedrosa; Menezes, Maria Angela de B.C. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Servico de Reator e Irradiacoes

    2007-07-01

    A procedure for the determination of {sup 226}Ra and {sup 228}Ra in water samples by using liquid scintillation spectrometry was applied. The chemical separation of radium as Ba(Ra)SO{sub 4} was performed by the usual method of coprecipitation with barium carrier. The precipitated was mixed with water, Instagel{sup TM} and Ultima Gold AB{sup TM} scintillation cocktails after the delay time for {sup 226}Ra/{sup 222}Rn radioactive equilibrium. Activities of {sup 226}Ra and {sup 228}Ra were inferred from the alpha and beta counting respectively. It was used the pulse shape analyzer and correction factors for minimizing mutual radiometric interferences. The combined standard uncertainties were evaluated using the law of uncertainty propagation by partial derivatives method. The difficulties of method are discussed. (author)

  15. Laser trapping of Ra-225 and Ra-226 and progress towards an electric dipole moment measurement

    Science.gov (United States)

    Guest, J. R.; Scielzo, N. D.; Ahmad, I.; Bailey, K.; Greene, J. P.; Holt, R. J.; Lu, Z.-T.; O'Connor, T. P.; Potterveld, D. H.

    2006-10-01

    Permanent electric dipole moments (EDMs) in atoms or molecules are signatures of Time (T)-and Parity (P)-violation and represent an important window onto physics beyond the Standard Model. We are developing a next generation EDM search around laser-cooled and trapped Ra-225 (t1/2 = 15 d). Due to octupole deformation of the nucleus, Ra-225 is predicted to be two to three orders of magnitude more sensitive to T-violating interactions than Hg-199, which currently sets the most stringent limits in the nuclear sector. We will discuss our progress, including the successful laser cooling and trapping of Ra-225 and Ra-226 atoms. We have demonstrated transverse cooling, Zeeman slowing, and capture of Ra-225 and Ra-226 atoms in a magneto-optical trap (MOT). By driving a second atomic transition, we have extended the lifetime of the trap from milliseconds to seconds and performed necessary spectroscopic measurements.

  16. Dreamweaver CS6 For Dummies

    CERN Document Server

    Warner, Janine

    2012-01-01

    Start creating websites that wow with the Dreamweaver CS6! Powerful yet easy to master, Dreamweaver is the dominant professional web development tool. Web design expert Janine Warner has updated her bestselling Dreamweaver For Dummies guide for the latest release of the software and walks you through the essential steps to building the website you’ve always wanted. Both beginning and intermediate web developers will get the information they need from this easy-to-follow reference to Dreamweaver CS6. Dreamweaver is the gold standard for website development software; this book covers wha

  17. Dreamweaver CS4 Digital Classroom

    CERN Document Server

    Osborn, Jeremy; Team, AGI Creative

    2011-01-01

    Dreamweaver CS4 Digital Classroom is like having a personal instructor guiding readers through each lesson, while they work at their own pace. This book includes 13 self-paced lessons that let readers discover essential skills and explore new features and capabilities of Adobe Dreamweaver CS4. Each lesson is presented in full color with step-by-step instructions. Learning is reinforced with video tutorials and lesson files on a companion DVD that were developed by the same team of Adobe Certified Instructors and Dreamweaver experts who have created many of the official training titles for Adob

  18. Photoshop CS6 For Dummies

    CERN Document Server

    Bauer, er

    2012-01-01

    The bestselling guide to the leading image-editing software, Photoshop CS6, fully updated! Want picture-perfect photos, every time? Get up to speed on the most popular professional photo-editing software on the market: Photoshop. In this new edition of Photoshop CS6 For Dummies, expert Peter Bauer shows you how to use the latest Photoshop tools to change a background, adjust brightness, improve color, or fix flaws. Richly illustrated in full color, this edition covers all the updates in the newest version of Photoshop, the gold standard for image-editing programs. Used by professional

  19. 90Sr and 89Sr in seawater off Japan as a consequence of the Fukushima Dai-ichi nuclear accident

    Directory of Open Access Journals (Sweden)

    K. O. Buesseler

    2013-02-01

    Full Text Available The impact of the earthquake and tsunami in the east coast of Japan in 11 March 2011 caused a loss of power at the Fukushima Dai-ichi Nuclear Power Plant (NPP that resulted in one of the most important releases of artificial radioactivity to the environment. Although several works were devoted to evaluate the atmospheric dispersion of radionuclides, the impact of the discharges to the ocean has been less investigated. Here we evaluate the distribution of Fukushima-derived 90Sr and 89Sr throughout waters 30–600 km offshore in June 2011. Concentrations of 90Sr and 89Sr in both surface waters and shallow profiles ranged from 0.8 ± 0.2 to 85 ± 3 Bq m−3 and from 19 ± 6 to 265 ± 74 Bq m−3, respectively. Because of its short half-life, all measured 89Sr was due to the accident, while the 90Sr concentrations can be compared to the background levels in the Pacific Ocean of about 1.2 Bq m−3. Fukushima-derived radiostrontium was mainly detected north of Kuroshio Current, as this was acting as a southern boundary for transport. The highest activities were associated with near-shore eddies, and larger inventories were found in the closest stations to Fukushima NPP. The data evidences a major influence of direct liquid discharges of radiostrontium compared to the atmospheric deposition. Existing 137Cs data reported from the same samples allowed us establishing a 90Sr/137Cs ratio of 0.0256 ± 0.0006 in seawater off Fukushima, being significantly different than that of the global atmospheric fallout (i.e. 0.63 and may be used in future studies to track waters coming from the east coast of Japan. Liquid discharges of 90Sr to the ocean were estimated, resulting in an inventory of 53 ± 1 TBq of 90Sr in the inshore study area in June 2011 and total releases of 90Sr ranging from 90 to 900 TBq, depending upon the reported estimates of 137Cs releases that are considered.

  20. 90Sr and 89Sr in seawater off Japan as a consequence of the Fukushima Dai-ichi nuclear accident

    Directory of Open Access Journals (Sweden)

    N. Casacuberta

    2013-06-01

    Full Text Available The impact of the earthquake and tsunami on the east coast of Japan on 11 March 2011 caused a loss of power at the Fukushima Dai-ichi nuclear power plant (NPP that resulted in one of the most important releases of artificial radioactivity into the environment. Although several works were devoted to evaluating the atmospheric dispersion of radionuclides, the impact of the discharges to the ocean has been less investigated. Here we evaluate the distribution of Fukushima-derived 90Sr (n = 57 and 89Sr (n = 19 throughout waters 30–600 km offshore in June 2011. Concentrations of 90Sr and 89Sr in both surface waters and shallow profiles ranged from 0.8 ± 0.2 to 85 ± 3 Bq m−3 and from 19 ± 6 to 265 ± 74 Bq m−3, respectively. Because of its short half-life, all measured 89Sr was due to the accident, while the 90Sr concentrations can be compared to the background levels in the Pacific Ocean of about 1.2 Bq m−3. Fukushima-derived radiostrontium was mainly detected north of Kuroshio Current, as this was acting as a southern boundary for transport. The highest activities were associated with near-shore eddies, and larger inventories were found in the closest stations to Fukushima NPP. The data evidence a major influence of direct liquid discharges of radiostrontium compared to the atmospheric deposition. Existing 137Cs data reported from the same samples allowed us to establish a 90Sr / 137Cs ratio of 0.0256 ± 0.0006 in seawater off Fukushima, being significantly different than that of the global atmospheric fallout (i.e., 0.63 and may be used in future studies to track waters coming from the east coast of Japan. Liquid discharges of 90Sr to the ocean were estimated, resulting in an inventory of 53 ± 1 TBq of 90Sr in the inshore study area in June 2011 and total releases of 90Sr ranging from 90 to 900 TBq, depending upon the reported estimates of 137Cs releases that are considered.

  1. 90Sr and 89Sr in seawater off Japan as a consequence of the Fukushima Dai-ichi nuclear accident

    Science.gov (United States)

    Casacuberta, N.; Masqué, P.; Garcia-Orellana, J.; Garcia-Tenorio, R.; Buesseler, K. O.

    2013-06-01

    The impact of the earthquake and tsunami on the east coast of Japan on 11 March 2011 caused a loss of power at the Fukushima Dai-ichi nuclear power plant (NPP) that resulted in one of the most important releases of artificial radioactivity into the environment. Although several works were devoted to evaluating the atmospheric dispersion of radionuclides, the impact of the discharges to the ocean has been less investigated. Here we evaluate the distribution of Fukushima-derived 90Sr (n = 57) and 89Sr (n = 19) throughout waters 30-600 km offshore in June 2011. Concentrations of 90Sr and 89Sr in both surface waters and shallow profiles ranged from 0.8 ± 0.2 to 85 ± 3 Bq m-3 and from 19 ± 6 to 265 ± 74 Bq m-3, respectively. Because of its short half-life, all measured 89Sr was due to the accident, while the 90Sr concentrations can be compared to the background levels in the Pacific Ocean of about 1.2 Bq m-3. Fukushima-derived radiostrontium was mainly detected north of Kuroshio Current, as this was acting as a southern boundary for transport. The highest activities were associated with near-shore eddies, and larger inventories were found in the closest stations to Fukushima NPP. The data evidence a major influence of direct liquid discharges of radiostrontium compared to the atmospheric deposition. Existing 137Cs data reported from the same samples allowed us to establish a 90Sr / 137Cs ratio of 0.0256 ± 0.0006 in seawater off Fukushima, being significantly different than that of the global atmospheric fallout (i.e., 0.63) and may be used in future studies to track waters coming from the east coast of Japan. Liquid discharges of 90Sr to the ocean were estimated, resulting in an inventory of 53 ± 1 TBq of 90Sr in the inshore study area in June 2011 and total releases of 90Sr ranging from 90 to 900 TBq, depending upon the reported estimates of 137Cs releases that are considered.

  2. CsMgPO4

    Directory of Open Access Journals (Sweden)

    Nikolay S. Slobodyanik

    2009-08-01

    Full Text Available Caesium magnesium orthophosphate is built up from MgO4 and PO4 tetrahedra (both with . m. symmetry linked together by corners, forming a three-dimensional framework. The Cs atoms have .m. site symmetry and are located in hexagonal channels running along the a- and b-axis directions.

  3. Expression pattern of the CsPK3 auxin-responsive protein kinase gene.

    Science.gov (United States)

    Chono, M; Suzuki, Y; Nemoto, K; Yamane, H; Murofushi, N; Yamaguchi, I

    2001-03-01

    We have previously cloned a cDNA of a putative serine/threonine protein kinase gene named CsPK3 from cucumber, the mRNA level of which was up-regulated by auxin and down-regulated by light irradiation. To examine the CsPK3 gene expression in detail, we cloned a genomic DNA of CsPK3 gene and made transgenic tobacco (Nicotiana tabacum L. cv. Petit Havana SR1) plants containing the fused CsPK3 promoter-beta-glucuronidase gene. The beta-glucuronidase expression was detected in the shoot apex, vascular tissues, and the outermost layer of cortex. The histological distribution of CsPK3 mRNA in cucumber seedlings was supported by in situ hybridization, where the positive signals were observed in similar tissues as those observed by beta-glucuronidase staining. The responsiveness of the CsPK3 gene to auxin and light was also confirmed for beta-glucuronidase activity. The pattern of beta-glucuronidase staining changed during the development of the tobacco seedlings. The results of our experiment showed that CsPK3 was expressed in a wide variety of tissues and cells in which the developmental and growth controls by auxin are suggested.

  4. Reactive barriers for 137Cs retention.

    Science.gov (United States)

    Krumhansl, J L; Brady, P V; Anderson, H L

    2001-02-01

    137Cs was dispersed globally by cold war activities and, more recently, by the Chernobyl accident. Engineered extraction of 137Cs from soils and groundwaters is exceedingly difficult. Because the half-life of 137Cs is only 30.2 years, remediation might be more effective (and less costly) if 137Cs bioavailability could be demonstrably limited for even a few decades by use of a reactive barrier. Essentially permanent isolation must be demonstrated in those few settings where high nuclear level wastes contaminated the environment with 135Cs (half-life 2.3 x 10(6) years) in addition to 137Cs. Clays are potentially a low-cost barrier to Cs movement, though their long-term effectiveness remains untested. To identify optimal clays for Cs retention, Cs desorption was measured for five common clays: Wyoming Montmorillonite (SWy-1), Georgia Kaolinites (KGa-1 and KGa-2), Fithian Illite (F-Ill), and K-Metabentonite (K-Mbt). Exchange sites were pre-saturated with 0.16 M CsCl for 14 days and readily exchangeable Cs was removed by a series of LiNO3 and LiCl washes. Washed clays were then placed into dialysis bags and the Cs release to the deionized water outside the bags measured. Release rates from 75 to 139 days for SWy-1, K-Mbt and F-Ill were similar; 0.017% to 0.021% sorbed Cs released per day. Both kaolinites released Cs more rapidly (0.12% to 0.05% of the sorbed Cs per day). In a second set of experiments, clays were Cs-doped for 110 days and subjected to an extreme and prolonged rinsing process. All the clays exhibited some capacity for irreversible Cs uptake. However, the residual loading was greatest on K-Mbt (approximately 0.33 wt.% Cs). Thus, this clay would be the optimal material for constructing artifical reactive barriers.

  5. Ra-226 and Pb-210/Ra-226 Activity Ratio in the Northern South China Sea

    Science.gov (United States)

    Chi-Ju, L.; Yu-Chia, C.; Tsung-En, W.

    2004-05-01

    The surface water distributions and vertical profiles of Ra-226 in the northern South China Sea (SCS) have been measured. Surface water Ra-226 varies between 10 and 16 dpm/100 kg with higher values at stations adjacent to the landmass. Each Ra-226 profile shows an increase from the surface toward the bottom. Above 1000m depth Ra-226 is systematically about 5 dpm/100kg higher in the northern South China Sea than in the western North Pacific. This difference may be attributed to a strong Ra-226 source from the shelf and slope area of the SCS. Below this depth Ra-226 displays large variation within some of the profiles with lower limits being comparable to the activities of the western North Pacific but higher limits being systematically about 5 dpm/100kg higher. These high Ra-226 activities may reflect effects of the longer isolation time for the deep water in the SCS basin and strong Ra input from the underlying sediments. The Pb-210/Ra-226 activity ratio ranges between 1.4 and 2.7 in the surface water with higher activity ratio at the station closer to the Luzon Strait. The Pb-210 in excess over Ra-226 in the surface water due to atmospheric input may penetrate to a depth of about 200 to 500m. Below this depth, Pb-210/Ra-226 activity ratio ranges between 0.5 and 0.7 because Pb-210 is scavenged by settling particulates. Box model calculations within a mixed layer of 50m in the area yield a mean residence time of about 1 yr for Pb-210 if an atmospheric Pb-210 flux of 1 dpm/cm2/y is adopted. The activity ratio of about 0.5 to 0.7 in the deep water corresponds to a Pb-210 mean residence time of about 30 to 70 yrs with respect to particulate scavenging.

  6. Sr isotopes and U series radionuclides in the Sangemini area (Central Italy: Hydrogeology implications

    Directory of Open Access Journals (Sweden)

    Maurizio Barbieri

    2014-06-01

    Full Text Available The strontium isotopic ratio (expressed as 87Sr/86Sr of groundwater represents a useful method for studying and understanding the groundwater circulations, also, the U and Ra isotopic compositions can vary as function of the groundwater residence time. This paper reports an evaluation of the probable recharge area of the Sangemini mineral water springs (Terni-Umbria Central Italy and an estimate of the residence time of the aquifer by coupling Sr and U series isotopic systematics. For this study have been analyzed four water sample for the isotope ratio of 87Sr/86Sr, and eleven samples, shallow waters and groundwaters, for U and Ra, furthermore were determined the values of isotopic ratio for sample of typical rocks of the area. The results of this study allow to identify: a recharge area in a restricted sector of the Meso-Cenozoic carbonates a longer and more effective water/rock interaction in the Quaternary series. U and Ra recoil models allow to estimate a groundwater residence time of about 350 years and a total water volume whose value (64*106 m3 agrees with the limited extension of the aquifer. The extension of the aquifer was constrained by comparing Sr isotopic composition of waters and local geological formations. Groundwaters seem mainly to circulate in clayey sandy Quaternary series characterized by low redox conditions.

  7. 228Ra, 226Ra, 224Ra and 223Ra in potential sources and sinks of land-derived material in the German Bight of the North Sea: implications for the use of radium as a tracer

    NARCIS (Netherlands)

    Schmidt, C.; Hanfland, C.; Regnier, P.; Van Cappellen, P.; Schlüter, M.; Knauthe, U.; Stimac, I.; Geibert, W.

    2011-01-01

    Activities of the naturally occurring radium nuclides 228Ra, 226Ra, 224Ra and 223Ra were determined in waters of the open German Bight and adjacent nearshore areas in the North Sea, in order to explore the potential use of radium isotopes as natural tracers of land–ocean interaction in an environmen

  8. ICMPv6 RA Flooding Vulnerability Research

    Directory of Open Access Journals (Sweden)

    Linas Jočys

    2016-06-01

    Full Text Available ICMPv6 is the newest version of internet control message protocol, whose main purpose is to send error message indicating packet processing failure. It is know that ICMPv6 is technologically vulnerable. One of those vulnerabilities is the ICMPv6 RA flooding vulnerability, which can lead to systems in Local Area Network slow down or full stop. This paper will discuss Windows (XP, 7, 8.1 and Linux Ubuntu 14 operating systems resistance to RA flooding attack research and countermeasures to minimize this vulnerability.

  9. Investigation of Adsorption Behavior of Ba and Other Fission Products on the Sr·spc Chromatographic Column by Static Method

    Institute of Scientific and Technical Information of China (English)

    YANG; Lei; MA; Peng; YANG; Su-liang; LIANG; Xiao-hu

    2012-01-01

    <正>Adsorption behavior of Ba, Cs and some other fission products on the Sr·spc resin has been investigated for the purpose of extracting 141Ba from the fission product. Sr·spc resin with the main functional group of 18-crown-6 ether was purchased from US. Eichrom Company. Tracers of Ba, Cs and some other fission products were acquired from an irradiated U target.

  10. Ag-loaded MgSrFe-layered double hydroxide/chitosan composite scaffold with enhanced osteogenic and antibacterial property for bone engineering tissue.

    Science.gov (United States)

    Cao, Dandan; Xu, Zhengliang; Chen, Yixuan; Ke, Qinfei; Zhang, Changqing; Guo, Yaping

    2017-04-17

    Bone tissue engineering scaffolds for the reconstruction of large bone defects should simultaneously promote osteogenic differentiation and avoid postoperative infection. Herein, we develop, for the first time, Ag-loaded MgSrFe-layered double hydroxide/chitosan (Ag-MgSrFe/CS) composite scaffold. This scaffold exhibits three-dimensional interconnected macroporous structure with a pore size of 100-300 μm. The layered double hydroxide nanoplates in the Ag-MgSrFe/CS show lateral sizes of 200-400 nm and thicknesses of ∼50 nm, and the Ag nanoparticles with particle sizes of ∼20 nm are uniformly dispersed on the scaffold surfaces. Human bone marrow-derived mesenchymal stem cells (hBMSCs) present good adhesion, spreading, and proliferation on the Ag-MgSrFe/CS composite scaffold, suggesting that the Ag and Sr elements in the composite scaffold have no toxicity to hBMSCs. When compared with MgFe/CS composite scaffold, the Ag-MgSrFe/CS composite scaffold has better osteogenic property. The released Sr(2+) ions from the composite scaffold enhance the alkaline phosphatase activity of hBMSCs, promote the extracellular matrix mineralization, and increase the expression levels of osteogenic-related RUNX2 and BMP-2. Moreover, the Ag-MgSrFe/CS composite scaffold possesses good antibacterial property because the Ag nanoparticles in the composite scaffold effectively prevent biofilm formation against S. aureus. Hence, the Ag-MgSrFe/CS composite scaffold with excellent osteoinductivity and antibacterial property has a great potential for bone tissue engineering. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2017. © 2017 Wiley Periodicals, Inc.

  11. Natural radionuclides and (137)Cs distributions and their relationship with sedimentological processes in Patras Harbour, Greece.

    Science.gov (United States)

    Papaefthymiou, H; Papatheodorou, G; Moustakli, A; Christodoulou, D; Geraga, M

    2007-01-01

    Surficial and subsurficial sediment samples derived from gravity cores, selected from the harbour of Patras, Greece, were analyzed for grain size, water content, bulk density, specific gravity, organic carbon content and specific activities of natural radionuclides and (137)Cs. The specific activities of (232)Th, (226)Ra, (40)K and (137)Cs were measured radiometrically. The radionuclides (238)U and (232)Th were also analyzed using the INAA. The differences found between the specific activities of the natural radionuclides measured by the two methods are of no statistical significance. The sediment cores selection was based on a detailed bathymetric and marine seismic survey. Through the study of the detailed bathymetric map and the seismic profiles it was shown that ship traffic is highly influential to the harbour bathymetry. The granulometric and geotechnical properties of the sediments and therefore the specific activities of the natural radionuclides and (137)Cs seem to be controlled by the ship traffic. Relationship between radionuclide activity concentrations and granulometric/geotechnical parameters was defined after the treatment of all the analyses using R-mode factor analysis. The natural radionuclide activities are related to the fine fraction and bulk density of the sediments, while (137)Cs is mainly influenced by the organic carbon content. In addition, (238)U and (226)Ra seem to be in close relation with the heavy minerals fraction in coarse-grained sediments with high specific gravity.

  12. Sedimentological study of a lagoon through natural radioactivity and 137Cs determinations

    Science.gov (United States)

    San Miguel, E. G.; Pérez-Moreno, J. P.; Aguado, J. L.; Bolívar, J. P.; García-Tenorio, R.

    2003-01-01

    Profiles of artificial fallout (such as 137Cs) and natural radioactivity radionuclides in sediment cores are useful tools to study sedimentological properties of different aquatic environments as well as to evaluate average sedimentation rates. In the Portil lagoon, a small natural reservoir located in Huelva province (southwest of Spain), and through the analysis of 210Pb, 226Ra, 137Cs, 238U and 210Po vertical profiles in sediment cores, it is shown how the accumulative or transport character of the collection zones may be inferred. In the accumulation zone of the lagoon the influence of focusing effects has been analysed and an average sedimentation rate has been determined through 210Pb in one sediment core. This 210Pb-sedimentation rate is consistent with sediment dating based on the 137Cs data.

  13. Preverjanje znanja računalništva, pridobljenega z aktivnostmi za učenje računalništva brez računalnika

    OpenAIRE

    Zaviršek, Manca

    2015-01-01

    V magistrskem delu obravnavamo ugotavljanje računalniškega znanja, ki ga učenci pridobijo z aktivnostmi Računalništvo brez računalnika. Najprej opredelimo, kaj sploh je računalniško znanje in kaj so računalniški koncepti, ter se posvetimo sodobnim pristopom k poučevanju računalništva, kjer je v ospredju reševanje problemov, uresničujemo pa jih lahko z aktivnostmi Računalništvo brez računalniki in z nalogami s tekmovanja Bober. V empiričnem delu nas zanima, ali je ugotavljanje znanja, pridoblj...

  14. A rotating target for Ra production

    NARCIS (Netherlands)

    Sohani, M.; Wilschut, H. W.

    2012-01-01

    A target wheel with pyrolytic graphite targets is designed and constructed at the TRI mu P facility to boost the production rate of Ra isotopes. Simulation, design properties and production results are discussed. (C) 2012 Elsevier B.V. All rights reserved.

  15. Neutron Resonance Parameters for Ra-226 (Radium)

    Science.gov (United States)

    Sukhoruchkin, S. I.; Soroko, Z. N.

    This document is part of the Supplement containing the complete sets of data of Volume 24 `Neutron Resonance Parameters' of Landolt-Börnstein - Group I `Elementary Particles, Nuclei and Atoms'. It provides the neutron resonance parameters for the isotope Ra-226 (Radium).

  16. ITER CS Model Coil and CS Insert Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Martovetsky, N; Michael, P; Minervina, J; Radovinsky, A; Takayasu, M; Thome, R; Ando, T; Isono, T; Kato, T; Nakajima, H; Nishijima, G; Nunoya, Y; Sugimoto, M; Takahashi, Y; Tsuji, H; Bessette, D; Okuno, K; Ricci, M

    2000-09-07

    The Inner and Outer modules of the Central Solenoid Model Coil (CSMC) were built by US and Japanese home teams in collaboration with European and Russian teams to demonstrate the feasibility of a superconducting Central Solenoid for ITER and other large tokamak reactors. The CSMC mass is about 120 t, OD is about 3.6 m and the stored energy is 640 MJ at 46 kA and peak field of 13 T. Testing of the CSMC and the CS Insert took place at Japan Atomic Energy Research Institute (JAERI) from mid March until mid August 2000. This paper presents the main results of the tests performed.

  17. Adobe Photoshop CS6 bible

    CERN Document Server

    Dayley, Brad

    2012-01-01

    The comprehensive, soup-to-nuts guide to Photoshop, fully updated Photoshop CS6, used for both print and digital media, is the industry leader in image-editing software. The newest version adds some exciting new features, and this bestselling guide has been revised to cover each of them, along with all the basic information you need to get started. Learn to use all the tools, including the histogram palette, Lens Blur, Match Color, and the color replacement tool, as well as keyboard shortcuts. Then master retouching and color correction, work with Camera Raw images, prepare photos for print

  18. Major scientific thematic areas: TA6 - radiation, protection of the public and the environment (Poster session 1) origin and migration of Cs-137 in Jordanian soils

    Energy Technology Data Exchange (ETDEWEB)

    Qwasmeh, A.; Fischer, H.W. [Bremen Univ., IUP- Institute for Environmental Physics (Germany)

    2006-07-01

    Whilst some research and publication has been done and published about natural radioactivity in Jordan, only one paper has been published about artificial radioactivity in Jordanian soils (Al Hamarneh 2003). It reveals high concentrations of {sup 137}Cs and {sup 90}Sr in some regions in the northwest section of Jordan. The origin of this contamination was not determined. Two sets of soil samples were collected and brought from northwest section of Jordan for two reasons, namely; the comparable high concentration of {sup 137}Cs in this region according to the above-mentioned paper and because most of the population concentrates in this region. The first set of samples was collected in April 2004 from eleven different sites of this region of Jordan. The second set of samples has been brought in July 2005 from six of the previous sites where we had found higher {sup 137}Cs contamination. The second set was collected as thinner sliced soil samples for further studying and to apply a suitable model for {sup 137}Cs migration in soil. Activity of {sup 137}Cs was measured using a Hp Ge detector of 50% relative efficiency and having resolution of 2 keV at 1.33 MeV. Activity of {sup 90}Sr was measured for the samples of four sites of the first set of samples, using a gas-filled proportional detector with efficiency of 21.3% cps/Bq. The total inventory of {sup 137}Cs in Bq/m{sup 2} has been calculated and the correlation between {sup 137}Cs inventory and annual rainfall and site Altitude has been studied. In order to determine the origin of {sup 137}Cs in the Jordanian soil we have used two methods; {sup 137}Cs - {sup 90}Sr ratio and the diffusion convection model which describes the migration of {sup 137}Cs in Soil. (authors)

  19. Genetics of RA susceptibility, what comes next?

    Science.gov (United States)

    Ding, James; Eyre, Stephen; Worthington, Jane

    2015-01-01

    Summary Genome-wide association studies (GWASs) have been used to great effect to identify genetic susceptibility loci for complex disease. A series of GWAS and meta-analyses have informed the discovery of over 100 loci for rheumatoid arthritis (RA). In common with findings in other autoimmune diseases the lead signals for the majority of these loci do not map to known gene sequences. In order to realise the benefit of investment in GWAS studies it is vital we determine how disease associated alleles function to influence disease processes. This is leading to rapid development in our knowledge as to the function of non-coding regions of the genome. Here we consider possible functional mechanisms for intergenic RA-associated variants which lie within lncRNA sequences. PMID:26509058

  20. Entrevista a Raúl Gagliardi.

    Directory of Open Access Journals (Sweden)

    Diego Campos (Pagina 1-7

    2008-10-01

    Full Text Available En el V encuentro de Enseñanza de la Biología y Educación Ambiental, celebrado los días 17, 18 y 19 de Junio del año en curso, los miembros del comité editorial de la revista del Departamento de Biología de la Universidad Pedagógica Nacional entrevistaron al conferencista internacional Raúl Galgliardi.

  1. Chôra : Creation and Pathology

    DEFF Research Database (Denmark)

    Isar, Nicoletta

    2009-01-01

    Plato's dialogue the Timaeus describes not only the making of the cosmos (order), but also the condition of what is not order, neither for the human body nor for the universe. What is disorder in cosmogonic terms it is disease for the human body. Timaeus applies to the concept chôra in discussing....... http://www.ejop.org/archives/2009/05/chara_creation.html...

  2. Determination of {sup 135}Cs and {sup 137}Cs in environmental samples: A review

    Energy Technology Data Exchange (ETDEWEB)

    Russell, B.C., E-mail: ben.russell@npl.co.uk [GAU-Radioanalytical, Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH (United Kingdom); National Physical Laboratory, Hampton Road, Teddington, Middlesex, TW11 0LW (United Kingdom); Croudace, Ian W.; Warwick, Phil E. [GAU-Radioanalytical, Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH (United Kingdom)

    2015-08-26

    Radionuclides of caesium are environmentally important since they are formed as significant high yield fission products ({sup 135}Cs and {sup 137}Cs) and activation products ({sup 134}Cs and {sup 136}Cs) during nuclear fission. They originate from a range of nuclear activities such as weapons testing, nuclear reprocessing and nuclear fuel cycle discharges and nuclear accidents. Whilst {sup 137}Cs, {sup 134}Cs and {sup 136}Cs are routinely measurable at high sensitivity by gamma spectrometry, routine detection of long-lived {sup 135}Cs by radiometric methods is challenging. This measurement is, however, important given its significance in long-term nuclear waste storage and disposal. Furthermore, the {sup 135}Cs/{sup 137}Cs ratio varies with reactor, weapon and fuel type, and accurate measurement of this ratio can therefore be used as a forensic tool in identifying the source(s) of nuclear contamination. The shorter-lived activation products {sup 134}Cs and {sup 136}Cs have a limited application but provide useful early information on fuel irradiation history and have importance in health physics. Detection of {sup 135}Cs (and {sup 137}Cs) is achievable by mass spectrometric techniques; most commonly inductively coupled plasma mass spectrometry (ICP-MS), as well as thermal ionisation (TIMS), accelerator (AMS) and resonance ionisation (RIMS) techniques. The critical issues affecting the accuracy and detection limits achievable by this technique are effective removal of barium to eliminate isobaric interferences arising from {sup 135}Ba and {sup 137}Ba, and elimination of peak tailing of stable {sup 133}Cs on {sup 135}Cs. Isobaric interferences can be removed by chemical separation, most commonly ion exchange chromatography, and/or instrumental separation using an ICP-MS equipped with a reaction cell. The removal of the peak tailing interference is dependent on the instrument used for final measurement. This review summarizes and compares the analytical procedures

  3. U-Th-Ra disequilibria in sediments of the Dora Baltea river (Italia)

    Science.gov (United States)

    Chabaux, F.; Deloche, A.; Pelt, E.; Granet, M.; Perrone, Th.; Boutin, R.; Viville, D.; Rihs, S.; Stille, P.

    2012-04-01

    In order to constrain the transfer time of sediments in Alpine rivers, we propose to use the U-series nuclides approach recently developed for Himalayan rivers (e.g., Chabaux et al., 2008; Granet et al., 2010). Therefore, a series of bank sediments has beeen collected along the Dora Baltea river (Italia), one of the Po's tributaries draining the southern slope of the Mont Blanc Massif. In addition to U series nuclides, major and trace element concentrations and Sr and Nd isotope ratios have been analyzed for each sample. The study indicates that the (234U/238U)-, (230Th/234U)- and the (226Ra/230Th)- activity ratios are very similar for all the samples, whereas the 230Th/232Th ratios can differ from one sample to another. Such a variation, consistent with the Sr and Nd isotope data, is certainly the consequence of mineralogical heterogeneities in the samples. This suggests that the use of 238U-230Th-232Th systematics alone is probably insufficient for constraining the transfer time of sediments in the Po rivers alluvial plain, whereas the combination of 238U-230Th disequilibrium with the 230Th-226Ra disequilibrium can help to constrain such time information.

  4. The absolute frequency of the 87Sr optical clock transition

    DEFF Research Database (Denmark)

    Campbell, Gretchen K.; Ludlow, Andrew D.; Blatt, Sebastian

    2008-01-01

    a detailed study of systematic effects, which reduced the total systematic uncertainty of the Sr lattice clock to 1.5 × 10-16, the clock frequency is measured against a hydrogen maser which is simultaneously calibrated to the US primary frequency standard, the NIST Cs fountain clock, NIST-F1. The comparison...

  5. Long-term stable stacked CsPbBr3 quantum dot films for highly efficient white light generation in LEDs.

    Science.gov (United States)

    Song, Young Hyun; Yoo, Jin Sun; Kang, Bong Kyun; Choi, Seung Hee; Ji, Eun Kyung; Jung, Hyun Suk; Yoon, Dae Ho

    2016-12-01

    We report highly efficient ethyl cellulose with CsPbBr3 perovskite QD films for white light generation in LED application. Ethyl cellulose with CsPbBr3 quantum dots is applied with Sr2Si5N8 : Eu(2+) red phosphor on an InGaN blue chip, achieving a highly efficient luminous efficacy of 67.93 lm W(-1) under 20 mA current.

  6. The Geography of the ta-ra-si-ja

    DEFF Research Database (Denmark)

    Nosch, Marie-Louise Bech

    2000-01-01

    Thies paper demonstrates how ta-ra-si-ja is connected to a fixed series of toponyms in Crete, and concludes that ta-ra-si-ja is a duty limited to certain places......Thies paper demonstrates how ta-ra-si-ja is connected to a fixed series of toponyms in Crete, and concludes that ta-ra-si-ja is a duty limited to certain places...

  7. Quantification of (226)Ra at environmental relevant levels in natural waters by ICP-MS: Optimization, validation and limitations of an extraction and preconcentration approach.

    Science.gov (United States)

    Lagacé, François; Foucher, Delphine; Surette, Céline; Clarisse, Olivier

    2017-05-15

    Radium (Ra) at environmental relevant levels in natural waters was determined by ICP-MS after an off-line pre-concentration procedure. The latter consisted of Ra selective elution from potential interfering elements (i.e. other alkaline earth cations: Ba(2+), Sr(2+), Ca(2+), Mg(2+)) on a series of two different ion exchange resins (AG50W-X8 and Sr-resin). The overall analytical method was optimized according to the instrumental performance, the volume of water sample loaded on resins, and the sample salinity. Longer acquisition time (up to 150 s) was required to ensure stable measurement of Ra by ICP-MS at ultra trace level (1.0pgL(-1)). For a synthetic groundwater spiked with Ra at 10.0pgL(-1), the analytical procedure demonstrated efficient separation of the analyte from its potential interfering elements and a complete recovery, independent of the sample volume tested from 10 up to 100mL. For synthetic seawater spiked at a level of 10.0pgL(-1) of Ra, the total load of salts on the two resins should not exceed 0.35g in order to ensure a complete separation and recovery of Ra. The method was validated on natural waters (i.e. groundwater, freshwater and seawater samples) spiked with Ra at different levels (0.0, 0.5, 1.0 and 5.0pgL(-1)). Absolute Ra detection limits were determined at 0.020pgL(-1) (0.73mBqL(-1)) and 0.12pgL(-1) (4.4mBqL(-1)) respectively for 60.0mL of freshwater sample and for 10.0mL of seawater. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. The low Sr/Ba ratio on some extremely metal-poor stars

    CERN Document Server

    Spite, M; Bonifacio, P; Caffau, E; François, P; Sbordone, L

    2014-01-01

    It has been noted that, in classical extremely metal-poor (EMP) stars, the abundance ratio of Sr and Ba, is always higher than [Sr/Ba] = -0.5, the value of the solar r-only process; however, a handful of EMP stars have recently been found with a very low Sr/Ba ratio. We try to understand the origin of this anomaly by comparing the abundance pattern of the elements in these stars and in the classical EMP stars. Four stars with very low Sr/Ba ratios were observed and analyzed within LTE approximation through 1D (hydrostatic) model atmosphere, providing homogeneous abundances of nine neutron-capture elements. In CS 22950-173, the only turnoff star of the sample, the Sr/Ba ratio is, in fact, found to be higher than the r-only solar ratio, so the star is discarded. The remaining stars (CS 29493-090, CS 30322-023, HE 305-4520) are cool evolved giants. They do not present a clear carbon enrichment. The abundance patterns of the neutron-capture elements in the three stars are strikingly similar to a theoretical s-pro...

  9. SR study of scintillators

    CERN Document Server

    Mikhailin, V V

    2000-01-01

    The technique and the models developed recently in Synchrotron Radiation (SR) Laboratory of Moscow University for the investigation of energy transfer processes in insulators can be applied for a detailed study of scintillator's properties. The experiments with SR in VUV and XUV regions allow to separate various processes and stages of energy transfer and help to indicate the dominating process on each stage. Thus, we can find the way to improve the properties, essential for the particular application of the scintillator: conversion efficiency, decay time, afterglow, radiation hardness, etc. The results of such a study can be used for the testing procedures in scintillator production.

  10. 浅谈4Cs

    Institute of Scientific and Technical Information of China (English)

    毛继光

    2000-01-01

    英语学习进入中高级阶段时,时常觉得英语的单词、词组或习惯用法越来越难掌握。本文想从另一角度为学习者提供一些词汇学习策略,引导学习者留心注意4Cs(collocative meaning,connotativemeaning,contextual meaning 和 cultural meaning)。本文虽是蜻蜓点水,但也许能为学习者提高语言意识开启一痢窗户。一、搭配意义(collocative meaning)

  11. Adsorption removal of Sr by Barium impregnated 4A Zeolite(BaA) from high radioactive seawater waste

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eil Hee; Lee, Keun Young; Kim, Kwang Wook; Kim, Ik Soo; Chung, Dong Yong; Moon, Jei Kwon; Choi, Jong Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-06-15

    This study investigated the removal of Sr, which was one of the high radioactive nuclides, by adsorption with Barium (Ba) impregnated 4A zeolite (BaA) from high-radioactive seawater waste (HSW). Adsorption of Sr by BaA (BaA-Sr), in the impregnated Ba concentration of above 20.2wt%, was decreased by increasing the impregnated Ba concentration, and the impregnated Ba concentration was suitable at 20.2wt%. The BaA-Sr adsorption was added to the co-precipitation of Sr with BaSO4 precipitation in the adsorption of Sr by 4A (4A-Sr) within BaA. Thus, it was possible to remove Sr more than 99% at m/V (adsorbent weight/solution volume)=5 g/L for BaA and m/V >20 g/L for 4A, respectively, in the Sr concentration of less than 0.2 mg/L (actual concentration level of Sr in HSW). It shows that BaA-Sr adsorption is better than 4A-Sr adsorption in for the removal capacity of Sr per unit gram of adsorbent, and the reduction of the secondary solid waste generation (spent adsorbent etc.). Also, BaA-Sr adsorption was more excellent removal capacity of Sr in the seawater waste than distilled water. Therefore, it seems to be effective for the direct removal of Sr from HSW. On the other hand, the adsorption of Cs by BaA (BaA-Cs) was mainly performed by 4A within BaA. Accordingly, it seems to be little effect of impregnated Ba into BaA. Meanwhile, BaA-Sr adsorption kinetics could be expressed the pseudosecond order rate equation. By increasing the initial Sr concentrations and the ratios of V/m, the adsorption rate constants (k2) were decreased, but the equilibrium adsorption capacities (qe) were increasing. However, with increasing the temperature of solution, k2 was conversely increased, and qe was decreased. The activation energy of BaA-Sr adsorption was 38 kJ/mol. Thus, the chemical adsorption seems to be dominant rather than physical adsorption, although it is not a chemisorption with strong bonding form.

  12. Natural gamma radioactivity and of {sup 137} Cs in soil of the Chimaltitan municipality, Jalisco, Mexico; Radiactividad gamma natural y del {sup 137} Cs en suelo del Municipio de Chimaltitan, Jalisco, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Garay, A.; Mireles, F.; Quirino, L.L.; Davila, J.I.; Rios, C.; Lugo, J.F.; Soriano, J.M.; Angoli, A. [UAEN-Universidad Autonoma de Zacatecas, Cipres 10, Frac. La Penuela, 98000 Zacatecas (Mexico)]. e-mail: albinogaray@hotmail.com.mx

    2003-07-01

    With the purpose of determining the activity due to the natural presence of the {sup 226} Ra, {sup 232} Th, {sup 40} K and {sup 137} Cs in soil samples, of the municipality of Chimaltitan Jalisco. A set of these samples was measured in a gamma ray spectrometric system based on a High-purity Germanium detector. It is well-known that approximately 87% of the dose of the received radiation by the population is due to sources of natural radiation and 13% of the anthropogenic radiation. The gamma radiation comes mainly from the {sup 40} K and of those radionuclides of the series of radioactive decay of {sup 238} U and {sup 232} Th that its find dispersed thoroughly in the terrestrial crust. In this work its were analyzed twenty-two soil samples. It is enlarged the activity characterization for the radioisotopes of {sup 226} Ra {sup 232} Th, {sup 40} K and {sup 137} Cs. (Author)

  13. The presence of natural radioactivity and 137Cs in the South China Sea bordering peninsular Malaysia.

    Science.gov (United States)

    Amin, Y M; Mahat, R H; Nor, R M; Khandaker, Mayeen Uddin; Takleef, Ghazwa Hatem; Bradley, D A

    2013-10-01

    The presence of natural radioactivity and (137)Cs has been investigated in fresh media obtained from South China Sea locations off the coast of peninsular Malaysia. The media include seafood, sea water and sediment. The samples were collected some weeks prior to the devastating 2011 Tōhoku earthquake and associated tsunami, the occurrence of which precipitated the Fukushima incident. All samples showed the presence of naturally occurring (226)Ra, (228)Ra and primordial (40)K, all at typically prevailing levels. The concentrations of natural radioactivity in molluscs were found to be greater than that of other marine life studied herein, the total activity ranging from 337 to 393 Bq kg(-1) dry weight. The total activity in sea water ranged from 15 to 88 Bq l(-1). Sediment samples obtained at deep sea locations more than 20 km offshore further revealed the presence of (137)Cs. The activity of (137)Cs varied from ND to 0.5 Bq kg(-1) dry weight, the activity increasing with offshore distance and depth. The activity concentrations presented herein should be considered useful in assessing the impact of any future radiological contamination to the marine environment.

  14. 134Cs: 137Cs and 106Ru: 137Cs ratios in intertidal sediments from the Cumbria and Lancashire coasts England

    Science.gov (United States)

    Stanners, D. A.; Aston, S. R.

    1981-10-01

    The distributions of 134Cs, 137Cs and 106Ru in intertidal surface sediments from the coasts of Cumbria and Lancashire, north-west England, are reported. The ratios of 134Cs: 137Cs and 106Ru: 137Cs activities have been used together with the isotopic composition of the Windscale radioactive effluents to examine the contamination history of sediments. Distinct differences between the activities and time of contamination of muds, silts and sands are found, and the apparent lag times of transport of radioactive wastes to different sediment localities are estimated. The relatively high activities in fine sediments reflect recent discharges indicating a rapid response to discharge, while the sands contain low levels of older contamination. Apparent lag times of up to 6 years are estimated for the study area; the transport to the south is generally more rapid than to the north. These results have consequences for the operation and interpretation of radiological monitoring in coastal areas.

  15. Investigation of the distribution of {sup 137}Cs in the surface layer of the Southern Ocean (Atlantic sector); Enquete sur la distribution de {sup 137}Cs dans la couche superficielle de l'ocean Austral (secteur de l'Atlantique)

    Energy Technology Data Exchange (ETDEWEB)

    Domanov, M.M. [P.P. Shirshov Institute of Oceanology, Russian Academy of Sciences, Nakhimovsky prospekt 36, 117997, Moscow (Russian Federation)

    2012-01-15

    An investigation of the latitudinal distribution of concentrations of {sup 137}Cs at 19 stations in the surface water of the Southern Ocean on cross-sections to the South from the Cape of Good Hope (section SR2) and in the Drake Passage (30. cruise 'Academic Ioffe', 01.12.2009-09.01.2010) was performed. The data obtained reinforced the time-dependent exponential decrease in the {sup 137}Cs concentrations in the surface water of the Atlantic sector of the Southern Ocean. Increased {sup 137}Cs concentrations were found in the Drake Passage and in the section SR2 in the vicinity of the Polar Front. The average value of {sup 137}Cs concentrations for all measurements equals 0.18 Bq.m{sup -3} {sigma} = 0.11. (author)

  16. Temperature and Pressure Dependence of the Reaction S plus CS (+M) -> CS2 (+M)

    DEFF Research Database (Denmark)

    Glarborg, Peter; Marshall, Paul; Troe, Juergen

    2015-01-01

    Experimental data for the unimolecular decomposition of CS2 from the literature are analyzed by unimolecular rate theory with the goal of obtaining rate constants for the reverse reaction S + CS (+M) -> CS2 (+M) over wide temperature and pressure ranges. The results constitute an important input...

  17. Cross equator transport of 137Cs from North Pacific Ocean to South Pacific Ocean ( BEAGLE2003 cruises)

    Science.gov (United States)

    Aoyama, M.; Fukasawa, M.; Hirose, K.; Hamajima, Y.; Kawano, T.; Povinec, P. P.; Sanchez-Cabeza, J. A.

    2011-04-01

    The anthropogenic radionuclides such as 137Cs, 90Sr, 99Tc, 129I and some transuranics are important tracers of transport and biogeochemical processes in the ocean. 137Cs, with a half-life of 30 years, a major fission product present in a dissolved form in seawater, is a good tracer of oceanic circulation at a time scale of several decades. At WOCE P6 line along 30°S during the BEAGLE cruise in 2003, surface seawater (around 80 L) was collected a few meters below the ocean surface by a pumping system. Water column samples (from 5 to 20 L) were collected using a Rosette multisampling system and Niskin bottles. 137Cs was separated from seawater samples using ammonium phosphomolybdate (AMP) and analysed for 137Cs in low-level HPGe gamma-ray spectrometers. Results allowed to draw a detailed picture of the distribution of 137Cs in the South Pacific Ocean along P6 line. A 137Cs depth section was depicted from about 160 samples. 137Cs concentrations in the subsurface layers ranged from 0.07 ± 0.04 Bq m -3 to 1.85 ± 0.145 Bq m -3, high in the Tasman Sea and very low in the eastern region where upwelling occurs. Water column inventories of 137Cs from surface to 1000 dbar depth ranged from 270 ± 104 to 1048 ± 127 Bq m -2. It was concluded that the source of higher 137Cs concentration and inventories in the Tasman Sea was 137Cs deposited in the mid latitude of the North Pacific Ocean and transported across the equator during four decades.

  18. CS Radar Imaging via Adaptive CAMP

    NARCIS (Netherlands)

    Anitori, L.; Otten, M.P.G.; Hoogeboom, P.

    2012-01-01

    In this paper we present results on application of Compressive Sensing (CS) to high resolution radar imaging and pro- pose the adaptive Complex Approximate Message Passing (CAMP) algorithm for image reconstruction. CS provides a theoretical framework that guarantees, under certain assumptions,

  19. CS Radar Imaging via Adaptive CAMP

    NARCIS (Netherlands)

    Anitori, L.; Otten, M.P.G.; Hoogeboom, P.

    2012-01-01

    In this paper we present results on application of Compressive Sensing (CS) to high resolution radar imaging and pro- pose the adaptive Complex Approximate Message Passing (CAMP) algorithm for image reconstruction. CS provides a theoretical framework that guarantees, under certain assumptions, recon

  20. The CS molecule in diffuse interstellar clouds

    NARCIS (Netherlands)

    Drdla, K.; Knapp, G.R.; Dishoeck, van E.F.

    1989-01-01

    The CS J = 2-1 emission line at 98 GHz has been searched for in 10 diffuse molecular clouds. CS column densities are derived by performing statistical equilibrium calculations for the rotational population distribution which includes collisional excitation by electrons as well as by neutral species.

  1. High-Speed RaPToRS

    Science.gov (United States)

    Henchen, Robert; Esham, Benjamin; Becker, William; Pogozelski, Edward; Padalino, Stephen; Sangster, Thomas; Glebov, Vladimir

    2008-11-01

    The High-Speed Rapid Pneumatic Transport of Radioactive Samples (HS-RaPToRS) system, designed to quickly and safely move radioactive materials, was assembled and tested at the Mercury facility of the Naval Research Laboratory (NRL) in Washington D.C. A sample, which is placed inside a four-inch-diameter carrier, is activated before being transported through a PVC tube via airflow. The carrier travels from the reaction chamber to the end station where it pneumatically brakes prior to the gate. A magnetic latch releases the gate when the carrier arrives and comes to rest. The airflow, optical carrier-monitoring devices, and end gate are controlled manually or automatically with LabView software. The installation and testing of the RaPToRS system at NRL was successfully completed with transport times of less than 3 seconds. The speed of the carrier averaged 16 m/s. Prospective facilities for similar systems include the Laboratory for Laser Energetics and the National Ignition Facility.

  2. Bone-seeking radiopharmaceuticals for treatment of osseous metastases, Part 1: α therapy with 223Ra-dichloride.

    Science.gov (United States)

    Pandit-Taskar, Neeta; Larson, Steven M; Carrasquillo, Jorge A

    2014-02-01

    Metastatic disease to bone is commonly seen in the advanced stages of many cancers. The cardinal symptom, pain, is often the cause of significant morbidity and reduced quality of life. Treatment of bone pain includes nonsteroidal analgesics and opiates; however, long-term use of these drugs is commonly associated with significant side effects, and tolerance is common. External-beam radiation therapy is effective mainly in localized disease sites. Bone-targeting radiopharmaceuticals are beneficial in the management of patients with multiple metastatic lesions. This article focuses on the 3 most commonly used agents: the Food and Drug Administration-approved (89)Sr-chloride, (153)Sm-ethylenediaminetetramethylene phosphonic acid (EDTMP), and (223)Ra-dichloride. We will discuss the physical characteristics, clinical data, dosage, and administration of these agents, including optimal patient selection and toxicity associated with their use. These radioactive agents have proven efficacy in the treatment of painful osseous metastases from prostate cancer and breast cancer. Significant recent advances include use of these agents in combination with chemotherapy and the use of the α emitter (223)Ra-dichloride in prostate cancer, primarily to improve survival and skeletal related events. The review is presented in 2 parts. The first will discuss the characteristics and clinical use of (223)Ra-dichloride, and the second will discuss the β emitters (89)Sr and (153)Sm-EDTMP.

  3. Desorption of 137Cs+ from mosses

    Directory of Open Access Journals (Sweden)

    OLGICA NEDIC

    2002-09-01

    Full Text Available Mosses are biomonitors that accumulate large amounts of various pollutants, including radionuclides. In this work we investigated the possibility of 137Cs extraction from mosses, as well as the significance of species specificity on the efficiency of 137Cs desorption. Salt and acid solutions were used as extraction media. It was shown that a 5 % solution of both ammonium oxalate and phosphoric acid was able to desorb 81.8 % of 137Cs+ from Homalothecium sericeum, which was 39.9 % more than desorption from water. At the same time, most of the desorbed 137Cs+ was incorporated in crystals that precipitated from the solution. An interspecies difference in respect to 137Cs+ desorption was noticed.

  4. Cs3ScCl6

    Directory of Open Access Journals (Sweden)

    Matthew D. Ward

    2014-06-01

    Full Text Available Crystals of tricaesium scandium(III hexachloride were obtained as a side product from the reaction of U, SnCl2, Sc, and S in a CsCl flux at 1073 K. Cs3ScCl6 crystallizes in the Rb3YCl6 structure type. The asymmetric unit comprises three Cs sites, two Sc sites, and six Cl sites, all of which have site symmetry 1, except for the two Sc sites that have site symmetries of 2 and -1, respectively. The structure is composed of isolated [ScCl6]3− octahedra that are surrounded by Cs+ cations. Two Cs+ cations have interactions with eight Cl− anions, while the third has interactions with ten Cl− anions.

  5. Cs2UPd3Se6

    Directory of Open Access Journals (Sweden)

    George N. Oh

    2011-02-01

    Full Text Available Dicaesium uranium(IV tripalladium(II hexaselenide, Cs2UPd3Se6, crystallizes in the space group Fmmm in the Ba2NaCu3O6 structure type. The asymmetric unit comprises the following atoms with site symmetries as shown: U1 (mm2, Cs1 (222, Cs2 (m2m, Pd1 (.m., Pd2 (2mm, Se1 (m.., and Se2 (1. This layered structure contains six edge-sharing square-planar [PdSe4] units that form a hexagon. These, in turn, edge-share with [USe6] trigonal–prismatic units, forming an extended layer parallel to (010. The layers are stacked along [010]. They are staggered, and are separated by the Cs atoms. The Cs atoms are either coordinated in a square antiprism of Se atoms or are ten-coordinate, with one square face and the opposite face hexagonal.

  6. Ra-224 and Ra-226: A New Method for Measuring Groundwater Seepage in Lake Michigan

    Science.gov (United States)

    Stevens, K. R.; Buyan, A. C.; Waples, J. T.

    2008-12-01

    Radium isotopes have been used to estimate groundwater discharge (GWD) in coastal marine waters for decades, but this technique has never before been used in the Laurentian Great Lakes. In this study, we used a RAD7 radon-in-air monitor to measure naturally-occurring radium isotopes Ra-224 (half-life= 3.64 d) and Ra-226 (half-life = 1600 a) in groundwater and three shallow water sites along Lake Michigan's Wisconsin coastline. Radium-224 activities in groundwater ranged from 1153 dpm m-3 in a deep aquifer (New Berlin well no.7) to 31 dpm m-3 in a shallow aquifer (Pryor well). Nearshore Lake Michigan measurements of Ra-224 were lowest at Red Arrow Beach (0.2 dpm m-3), higher in the Milwaukee harbor (GLWI slip, 1.1 dpm m-3) and highest at Harrington Beach (4.1 dpm m-3) and correspond well with groundwater seepage estimates made by Cherkauer et al. (1990) using alternate methods (i.e., where higher radium activity is indicative of higher GWD). These Ra-224 measurements are the first ever made in Lake Michigan (and presumably any of the Great Lakes) and we conclude that, by sampling offshore radium activity gradients, this RAD7 technique is a viable method for directly measuring GWD in Lake Michigan and other freshwater systems.

  7. Completion of CS insert fabrication; CS insato {center_dot} koiru no kansei

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, M.; Isono, T.; Koizumi, N. [and others

    1999-11-10

    In CS model coil plan which was development programs which make center of the ITER engineering design activity, the production of the CS insert coil by the production finished about this. It is a coil made of Nb3Sn-CICC for installing the CS insert coil at the most internal layer of the CS model coil, and for in magnetic flux density, current, temperature and under the strain environment equal to ITER real machine, it tests the superconductive conductor in performance. We report the progress of the CS insert coil production. (NEDO)

  8. Assessment of natural radioactivity and (137)Cs in some coastal areas of the Saudi Arabian gulf.

    Science.gov (United States)

    Al-Ghamdi, H; Al-Muqrin, A; El-Sharkawy, A

    2016-03-15

    The levels of natural radioactivity have been investigated in some Saudi Arabian Gulf coastal areas. Sampling sites were chosen according to the presence of nearby non-nuclear industrial activities such as, the two main water desalination plants in Al Khobar and Al Jubail, and Maaden phosphate complex in Ras Al Khair, to ensure that effluents discharges into the Arabian Gulf didn't enhance radioactivity in seawater and shore sediments. Seawater samples were analyzed for radium isotopes (Ra-226 & Ra-228) and measured by gamma spectrometry using high purity germanium detector, after radiochemical separation of the isotopes by co-precipitation with MnO2. Shore sediment samples were analyzed for (226)Ra, (228)Ra ((232)Th), (4)°K and (137)Cs using gamma sepectrometry. A small variation was observed in the activity concentrations of the investigated radioisotopes, and the activity levels were comparable to those reported in literature. Quality assurance and methods validation were established through the efficiency calibration of the detectors, the estimation of uncertainties, the use of blanks, the analysis of standard reference materials and the intercomparison and proficiency tests. Radiological hazards were assessed, and the annual effective dose had an average value of 0.02 mSv. On the basis of the current results, we may conclude that any radiological hazards to the public visiting these shores are not expected.

  9. SR-71 flyover

    Science.gov (United States)

    1990-01-01

    This clip, running about 14 seconds in length, shows the NASA SR-71 (No. 844) lighting off the afterburners on a low pass over the Dryden Flight Research Center. Two SR-71A aircraft on loan from the U.S. Air Force have been used for high-speed, high-altitude research at the NASA Dryden Flight Research Center, Edwards, California, since 1991. One of them was later returned to the Air Force. A third SR-71 on loan from the Air Force is an SR-71B used for training but not for flight research. Developed for the U.S. Air Force as reconnaissance aircraft more than 30 years ago, SR-71 aircraft are still the world's fastest and highest-flying production aircraft. These aircraft can fly more than 2200 miles per hour (Mach 3+ or more than three times the speed of sound) and at altitudes of over 85,000 feet. This operating environment makes the aircraft excellent platforms to carry out research and experiments in a variety of areas--aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic-boom characterization. Data from the SR-71 high-speed research program may be used to aid designers of future supersonic or hypersonic aircraft and propulsion systems, including a possible high-speed civil transport. The SR-71 program at Dryden has been part of the NASA overall high-speed aeronautical research program, and projects have involved other NASA research centers, other government agencies, universities, and commercial firms. One of the first major experiments to be flown in the NASA SR-71 program was a laser air-data collection system. This system used laser light instead of air pressure to produce airspeed and attitude reference data such as angle of attack and angle of sideslip. These data are normally obtained with small tubes and vanes extending into the air stream, or from tubes with flush openings on the aircraft outer skin. The flights provided information on the presence of

  10. SR-71 flight

    Science.gov (United States)

    1990-01-01

    The movie clip shown here runs about 13 seconds and shows an air-to-air shot of the front of the SR-71 aircraft and a head-on view of it coming in for a landing. Two SR-71A aircraft on loan from the U.S. Air Force have been used for high-speed, high-altitude research at the NASA Dryden Flight Research Center, Edwards, California, since 1991. One of them was later returned to the Air Force. A third SR-71 on loan from the Air Force is an SR-71B used for training but not for flight research. Developed for the U.S. Air Force as reconnaissance aircraft more than 30 years ago, SR-71 aircraft are still the world's fastest and highest-flying production aircraft. These aircraft can fly more than 2200 miles per hour (Mach 3+ or more than three times the speed of sound) and at altitudes of over 85,000 feet. This operating environment makes the aircraft excellent platforms to carry out research and experiments in a variety of areas--aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic-boom characterization. Data from the SR-71 high-speed research program may be used to aid designers of future supersonic or hypersonic aircraft and propulsion systems, including a possible high-speed civil transport. The SR-71 program at Dryden has been part of the NASA overall high-speed aeronautical research program, and projects have involved other NASA research centers, other government agencies, universities, and commercial firms. One of the first major experiments to be flown in the NASA SR-71 program was a laser air-data collection system. This system used laser light instead of air pressure to produce airspeed and attitude reference data such as angle of attack and angle of sideslip. These data are normally obtained with small tubes and vanes extending into the air stream, or from tubes with flush openings on the aircraft outer skin. The flights provided information on the presence of

  11. Molecular CsF{sub 5} and CsF{sub 2}{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Rogachev, Andrey Yu. [Illinois Institute of Technology, IL (United States). Dept. of Biological and Chemical Sciences; Miao, Mao-sheng [California State Univ., Northridge, CA (United States). Dept. of Chemistry and Biochemistry; Beijing Computational Science Research Center (China); Merino, Gabriel [Centro de Investigacion y de Estudios Avanzados, Unidad Merida (Mexico). Dept. de Fisica Aplicada; Hoffmann, Roald [Cornell Univ., Ithaca, NY (United States). Dept. of Chemistry and Chemical Biology

    2015-07-06

    D{sub 5h} star-like CsF{sub 5}, formally isoelectronic with known XeF{sub 5}{sup -} ion, is computed to be a local minimum on the potential energy surface of CsF{sub 5}, surrounded by reasonably large activation energies for its exothermic decomposition to CsF + 2F{sub 2}, or to CsF{sub 3} (three isomeric forms) + F{sub 2}, or for rearrangement to a significantly more stable isomer, a classical Cs{sup +} complex of F{sub 5}{sup -}. Similarly the CsF{sub 2}{sup +} ion is computed to be metastable in two isomeric forms. In the more symmetrical structures of these molecules there is definite involvement in bonding of the formally core 5p levels of Cs.

  12. Radioactive contamination of SrI2(Eu) crystal scintillator

    CERN Document Server

    Belli, P; Cerulli, R; Danevich, F A; Galenin, E; Gektin, A; Incicchitti, A; Isaienko, V; Kobychev, V V; Laubenstein, M; Nagorny, S S; Podviyanuk, R B; Tkachenko, S; Tretyak, V I

    2011-01-01

    A strontium iodide crystal doped by europium (SrI2(Eu)) was produced by using the Stockbarger growth technique. The crystal was subjected to characterisation that included relative photoelectron output and energy resolution for gamma quanta. The intrinsic radioactivity of SrI2(Eu) crystal scintillator was tested both in scintillation mode and by using ultra-low background HPGe gamma spectrometry deep underground. The response of the SrI2(Eu) detector to alpha particles (alpha/beta ratio and pulse shape) was estimated by analysing the 226Ra trace contamination internal to the crystal. We have found alpha/beta=0.55 and no difference in scintillation decay for alpha particles and gamma quanta. The application of the obtained results in the search for the double electron capture and electron capture with positron emission in 84Sr has been investigated at a level of sensitivity T_1/2 \\sim 10^15-10^16 yr. The results of these studies demonstrate the potentiality of this material for a variety of scintillation appli...

  13. Potential value of Cs-137 capsules

    Energy Technology Data Exchange (ETDEWEB)

    Bloomster, C.H.; Brown, D.R.; Bruno, G.A.; Hazelton, R.F.; Hendrickson, P.L.; Lezberg, A.J.; Tingey, G.L.; Wilfert, G.L.

    1985-04-01

    We determined the value of Cs-137 compared to Co-60 as a source for the irradiation of fruit (apples and cherries), pork and medical supplies. Cs-137, in the WESF capsule form, had a value of approximately $0.40/Ci as a substitute for Co-60 priced at approximately $1.00/Ci. The comparison was based on the available curies emitted from the surface of each capsule. We developed preliminary designs for fourteen irradiation facilities; seven were based on Co-60 and seven were based on Cs-137. These designs provided the basis for estimating capital and operating costs which, in turn, provided the basis for determining the value of Cs-137 relative to Co-60 in these applications. We evaluated the effect of the size of the irradiation facility on the value of Cs-137. The cost of irradiation is low compared to the value of the product. Irradiation of apples for disinfestation costs $.01 to .02 per pound. Irradiation for trichina-safe pork costs $.02 per pound. Irradiation of medical supplies for sterilization costs $.07 to .12 per pound. The cost of the irradiation source, either Co-60 or Cs-137, contributed only a minor amount to the total cost of irradiation, about 5% for the fruit and hog cases and about 20% for the medical supply cases. We analyzed the sensitivity of the irradiation costs and Cs-137 value to several key assumptions.

  14. Properties of Cs-intercalated single wall carbon nanotubes investigated by 133Cs Nuclear Magnetic resonance

    KAUST Repository

    Schmid, Marc R.

    2012-11-01

    In the present study, we investigated Cs-intercalated single wall carbon nanotubes (SWCNTs) using 133Cs Nuclear Magnetic resonance. We show that there are two types of Cs cations depending on the insertion level. Indeed, at low concentrations, Static spectra analysis shows that the Cs (α)+ species are fully ionized, i.e. α equal ca.1, while at higher concentrations a second paramagnetically shifted line appears, indicating the formation of Cs (β)+ ions with β < α ∼ +1. At low concentrations and low temperatures the Cs (α)+ ions exhibit a weak hyperfine coupling to the SWCNT conduction electrons, whereas, at higher temperatures, a thermally activated slow-motion diffusion process of the Cs (α)+ ions occurs along the interstitial channels present within the carbon nanotube bundles. At high concentrations, the Cs (β)+ ions seem to occupy well defined positions relative to the carbon lattice. As a matter of fact, the Korringa relaxation behavior suggests a strong hyperfine coupling between Cs nuclei and conduction electrons in the carbon nanotubes and a partial charge transfer, which suggest a plausible Cs(6s)-C(2p) hybridization. © 2012 Elsevier Ltd. All rights reserved.

  15. IL-1Ra: its role in rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    M. Cutolo

    2011-09-01

    Full Text Available Interleukin-1 (IL-1 is one of the pivotal cytokines in initiating and driving the processes of rheumatoid arthritis (RA, and the body’s natural response, IL-1 receptor antagonist (IL-1Ra, has been shown conclusively to block its effects. IL-1 mediate several clinical symptoms of the inflammatory reaction (i.e. fever, pain, sleep disturbances. IL-1 is considered a key mediator in RA joint damage because of its greater capacity (greater than TNF of increasing matrix degradation by inducing the production of MMPs and PGE2 in synovial cells, as well by its role as mediator of bone and cartilage destruction. In addition, IL-1 decreases the repair process by suppressing matrix synthesis and shows a strong synergism with TNF in inducing many inflammatory genes at both local and systemic level. The induced endogenous production of IL-1Ra, in presence of the RA synovitis, is too low to contrast the high affinity of IL-1 for the cell receptors. Therefore, IL-1Ra presence should result in very effective prevention of IL-1 signal transduction particularly in the inflammatory site. In laboratory and animal studies inhibition of IL-1 by either antibodies to IL-1 or IL-1Ra proved beneficial to the outcome. IL-1Ra is a member of the IL-1 superfamily. The effects of different DMARDs on IL-1Ra levels in RA patients support the important role that selected anticytokine treatments might exert in the pathophysiology of the disease. However, since anti TNFα therapy it is not effective in all RA patients, nor does it fully control the arthritic process in affected joints of good responders and complete TNF suppression should be avoided, the combined treatment with intermediate doses of TNF and IL-1 blockers, reaching synergistic suppression of arthritis, seems warranted in RA.

  16. Determination of 210Pb, 210Po, 226Ra, 228Ra and uranium isotopes in drinking water in order to comply with the requirements of the EU ‘Drinking Water Directive.

    Science.gov (United States)

    Vasile, M; Loots, H; Jacobs, K; Verheyen, L; Sneyers, L; Verrezen, F; Bruggeman, M

    2016-03-01

    The European Union published in 2013 a new Drinking Water Directive with stricter requirements for measuring natural radioactivity. In order to adhere to this, a method for sequential separation of 210Pb, 210Po, 238U and 234U in drinking water was applied using UTEVA® and Sr resins. Polonium-210, 238U and 234U were quantified using alpha-particle spectrometry and 210Pb using liquid scintillation counting. Radium-226 and 228Ra were determined using 3M Empore Radium RAD Disks, and their quantification was done using a Quantulus™ 1220 liquid scintillation counter.

  17. LoRA: A Loudspeaker-Based Room Auralization System

    DEFF Research Database (Denmark)

    Favrot, Sylvain Emmanuel; Buchholz, Jörg

    2010-01-01

    In order to study basic human perception in reverberant environments, a novel loudspeaker-based room auralization (LoRA) system is proposed in this paper. The LoRA system efficiently combines modern room acoustic models with high-order Ambisonic auralization. An objective evaluation has been...... carried out demonstrating the applicability of the LoRA system. Room acoustic parameters (reverberation time, clarity, speech transmission index and inter-aural cross correlation coefficients) of room impulse responses were compared at the input and the simulated output of the LoRA system. Results show...

  18. Drugs or disease: evaluating salivary function in RA patients

    Directory of Open Access Journals (Sweden)

    Sandra Regina TORRES

    Full Text Available Abstract Oral complications of RA may include temporomandibular joint disorders, mucosa alterations and symptoms of dry mouth. The aim of this study was to evaluate the salivary gland function of subjects with rheumatoid arthritis (RA comparing it to healthy controls. Subjects with other systemic conditions known to affect salivary functions were excluded. A questionnaire was applied for the evaluation of xerostomia. Resting and chewing-stimulated salivary flow rates (SFR were obtained under standard conditions. There were 145 subjects included of the study (104 RA and 38 controls. About 66.7% of the RA subjects and 2.4% in control group presented xerostomia. The median resting SFR were 0.24 ml/min for RA subjects and 0.40 mL/min for controls (p = 0.04. The median stimulated SFR were 1.31 mL/min for RA subjects and 1.52 ml/min for controls (p = 0.33. No significant differences were found between resting and stimulated SFR of RA subjects not using xerogenic medications and controls. There was significantly higher number of subjects presenting hyposalivation in the RA group than among controls, even when subjects using xerogenic medications were eliminated from the analysis. In conclusion, hyposalivation and xerostomia were more frequent among RA subjects not using xerogenic medication than among controls, although there were no significant differences in the median SFR between groups.

  19. Separation of Ra/Ca by ion exchange; Separacion de Ra/Ca por intercambio ionico

    Energy Technology Data Exchange (ETDEWEB)

    Iturbe, J.L.; Jimenez R, M.; Flores M, J

    1991-04-15

    The radium and the calcium belong to the same group in the periodic classification and as consequence both they present very similar chemical properties, that makes difficult its separation. Both elements are also frequently associate in the nature, the calcium is very abundant, the radium is not it and for that reason it is indispensable its separation to analyze to this last one. The alpha spectroscopy is very appropriate to analyze to the {sup 226} Ra, however to achieve a good resolution of the spectra, the samples should contain small quantities of calcium. The purposes of this work were to know the chromatographic behavior of the alkaline-earthy cations: calcium, barium and radium and to apply these knowledge to the separation of the {sup 226} Ra and its analysis by means of alpha spectroscopy. (Author)

  20. Doses from 222Rn, 226Ra, and 228Ra in groundwater from Guarani aquifer, South America.

    Science.gov (United States)

    Bonotto, D M

    2004-01-01

    Groundwater samples were analysed for 222Rn, 226Ra, and 228Ra in Guarani aquifer spreading around 1 million km2 within four countries in South America, and it was found that their activity concentrations are lognormally distributed. Population-weighted average activity concentration for these radionuclides allowed to estimate a value either slightly higher (0.13 mSv/year) than 0.1 mSv for the total effective dose or two times higher (0.21 mSv/year) than this limit, depending on the choice of the dose conversion factor. Such calculation adds useful information for the appropriate management of this transboundary aquifer that is socially and economically very important to about 15 million inhabitants living in Brazil, Argentina, Uruguay and Paraguay.

  1. Laser-trapping of Ra-225 and Ra-226 with repumping by room temperature blackbody radiation

    CERN Document Server

    Guest, J R; Bailey, K; Greene, J P; Holt, R J; Lu, Z T; O'Connor, T P; Potterveld, D H; Scielzo, N D

    2007-01-01

    We have demonstrated Zeeman slowing and capture of neutral Ra-225 and Ra-226 atoms in a magneto-optical trap (MOT). The intercombination transition 1S0-3P1 is the only quasi-cycling transition in radium and was used for laser-cooling and trapping. Repumping along the 3D1-1P1 transition extended the lifetime of the trap from milliseconds to seconds. Room-temperature blackbody radiation was demonstrated to provide repumping from the metastable 3P0 level. We measured the isotope shift and hyperfine splittings on the 3D1-1P1 transition with the laser-cooled atoms, and set a limit on the lifetime of the 3D1 level based on the measured blackbody repumping rate. Laser-cooled and trapped radium is an attractive system for studying fundamental symmetries.

  2. PRODUCT: ADOBE CS6 MASTER COLLECTION

    National Research Council Canada - National Science Library

    Carol S Holzberg

    2012-01-01

      Overall Rating: Whether you're editing a gallery of photos for a year book, producing a video for a school Web site, or "publishing" a research project for display on multiple devices, several Adobe CS6 tools get...

  3. The "Seven Cs" for Employee Retention.

    Science.gov (United States)

    Taguchi, Sherrie Gong

    2001-01-01

    Defines the "Seven Cs," traditional yet effective business fundamentals used to engage employees. Discusses how many companies are leveraging the basics of good employee relations in order to inspire staff productivity and loyalty. (GCP)

  4. The "Seven Cs" for Employee Retention.

    Science.gov (United States)

    Taguchi, Sherrie Gong

    2001-01-01

    Defines the "Seven Cs," traditional yet effective business fundamentals used to engage employees. Discusses how many companies are leveraging the basics of good employee relations in order to inspire staff productivity and loyalty. (GCP)

  5. PyCS : Python Curve Shifting

    Science.gov (United States)

    Tewes, Malte

    2015-09-01

    PyCS is a software toolbox to estimate time delays between multiple images of strongly lensed quasars, from resolved light curves such as obtained by the COSMOGRAIL monitoring program. The pycs package defines a collection of classes and high level functions, that you can script in a flexible way. PyCS makes it easy to compare different point estimators (including your own) without much code integration. The package heavily depends on numpy, scipy, and matplotlib.

  6. Lukács: ontologia e historicidade

    Directory of Open Access Journals (Sweden)

    Sergio Lessa

    1996-12-01

    Full Text Available O artigo argumenta que um dos principais momentos de ruptura de Lukács com as ontologias anteriores reside na sua inovadora distinção entre essência e fenômeno, a partir da peculiar relação de cada um com a categoria da continuidade. Assim procedendo, Lukács pôde resgatar a radical historicidade do mundo dos homens.

  7. Determination of {sup 226}Ra and {sup 224}Ra in sediments samples by liquid scintillation counting

    Energy Technology Data Exchange (ETDEWEB)

    Villa, M. [Facultad de Fisica. Av. Reina Mercedes s/n, apdo 1065, Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, 41080-Sevilla (Spain)]. E-mail: mvilla@us.es; Moreno, H.P. [E.T.S. Arquitectura. Av. Reina Mercedes, 2, Departamento de Fisica Aplicada II, Universidad de Sevilla, 41012-Sevilla (Spain); Manjon, G. [E.T.S. Arquitectura. Av. Reina Mercedes, 2, Departamento de Fisica Aplicada II, Universidad de Sevilla, 41012-Sevilla (Spain)

    2005-10-01

    An experimental procedure has been developed for a rapid determination of the activity concentration of {sup 226}Ra and {sup 224}Ra in sediments by liquid scintillation counting. The importance of the method lies in its application to the measurement of sediments where the Ra-isotopes activity concentration has been increased due to an anthropomorphic enhancement based on releases of naturally occurring radioactive material (NORM). A sample pre-treatment, including a digestion with aqua regia and a precipitation of hydroxides, was applied to samples before the radium extraction, which was made by co-precipitation with barium. Measurements were done in a low background scintillation spectrometer Quantulus 1220, which can separate and detect simultaneously {alpha} and {beta} particles. Additionally, some improvements are suggested for a better {alpha} and {beta} interference correction of the results. The obtaining of radiochemical yields is also improved using {sup 133}Ba as tracer, which decays by emission of conversion electrons and {gamma}-rays; the wide range of radiochemical yields obtained confirms the need of this analyses. The procedure has been applied to the measurement of riverbed sediments from an estuary in the south-west of Spain, affected in the past by direct and indirect phosphogypsum discharges.

  8. 135Cs activity and 135Cs/137Cs atom ratio in environmental samples before and after the Fukushima Daiichi Nuclear Power Plant accident

    Science.gov (United States)

    Yang, Guosheng; Tazoe, Hirofumi; Yamada, Masatoshi

    2016-04-01

    135Cs/137Cs is a potential tracer for radiocesium source identification. However, due to the challenge to measure 135Cs, there were no 135Cs data available for Japanese environmental samples before the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. It was only 3 years after the accident that limited 135Cs values could be measured in heavily contaminated environmental samples. In the present study, activities of 134Cs, 135Cs, and 137Cs, along with their ratios in 67 soil and plant samples heavily and lightly contaminated by the FDNPP accident were measured by combining γ spectrometry with ICP-MS/MS. The arithmetic means of the 134Cs/137Cs activity ratio (1.033 ± 0.006) and 135Cs/137Cs atom ratio (0.334 ± 0.005) (decay corrected to March 11, 2011), from old leaves of plants collected immediately after the FDNPP accident, were confirmed to represent the FDNPP derived radiocesium signature. Subsequently, for the first time, trace 135Cs amounts before the FDNPP accident were deduced according to the contribution of global and FDNPP accident-derived fallout. Apart from two soil samples with a tiny global fallout contribution, contributions of global fallout radiocesium in other soil samples were observed to be 0.338%–52.6%. The obtained 135Cs/137Cs database will be useful for its application as a geochemical tracer in the future.

  9. Cs3Sm7Se12

    Directory of Open Access Journals (Sweden)

    Christof Schneck

    2012-01-01

    Full Text Available The title compound, tricaesium heptasamarium(III dodecaselenide, is setting a new starting point for realization of the channel structure of the Cs3M7Se12 series, now with M = Sm, Gd–Er. This Cs3Y7Se12-type arrangement is structurally based on the Z-type sesquiselenides M2Se3 adopting the Sc2S3 structure. Thus, the structural set-up of Cs3Sm7Se12 consists of edge- and vertex-connected [SmSe6]9− octahedra [dØ(Sm3+ – Se2− = 2.931 Å], forming a rock-salt-related network [Sm7Se12]3− with channels along [001] that are apt to take up monovalent cations (here Cs+ with coordination numbers of 7 + 1 for one and of 6 for the second cation. The latter cation has a trigonal–prismatic coordination and shows half-occupancy, resulting in an impossible short distance [2.394 (4 Å] between symmetrically coupled Cs+ cations of the same kind. While one Sm atom occupies Wyckoff position 2b with site symmetry ..2/m, all other 11 crystallographically different atoms (namely 2 × Cs, 3 × Sm and 6 × Se are located at Wyckoff positions 4g with site symmetry ..m.

  10. Cs(3)Sm(7)Se(12).

    Science.gov (United States)

    Schneck, Christof; Elbe, Andreas; Schurz, Christian M; Schleid, Thomas

    2012-01-01

    The title compound, tricaesium hepta-samarium(III) dodeca-selenide, is setting a new starting point for realization of the channel structure of the Cs(3)M(7)Se(12) series, now with M = Sm, Gd-Er. This Cs(3)Y(7)Se(12)-type arrangement is structurally based on the Z-type sesquiselenides M(2)Se(3) adopting the Sc(2)S(3) structure. Thus, the structural set-up of Cs(3)Sm(7)Se(12) consists of edge- and vertex-connected [SmSe(6)](9-) octa-hedra [d(Ø)(Sm(3+) - Se(2-)) = 2.931 Å], forming a rock-salt-related network [Sm(7)Se(12)](3-) with channels along [001] that are apt to take up monovalent cations (here Cs(+)) with coordination numbers of 7 + 1 for one and of 6 for the second cation. The latter cation has a trigonal-prismatic coordination and shows half-occupancy, resulting in an impossible short distance [2.394 (4) Å] between symmetrically coupled Cs(+) cations of the same kind. While one Sm atom occupies Wyckoff position 2b with site symmetry ..2/m, all other 11 crystallographically different atoms (namely 2 × Cs, 3 × Sm and 6 × Se) are located at Wyckoff positions 4g with site symmetry ..m.

  11. The superconducting phase and electronic excitations of (Rb,Cs) Fe 2 As 2

    Science.gov (United States)

    Kanter, J.; Shermadini, Z.; Khasanov, R.; Amato, A.; Bukowski, Z.; Batlogg, B.

    2011-03-01

    We present specific heat, transport and Muon-Spin Rotation (μ SR) results on (Rb,Cs) Fe 2 As 2 . RbFe 2 As 2 was only recently found to be superconducting below 2.6 K by Bukowski et al. Compared to the related BaFe 2 As 2 the electron density is lower and no magnetic order is observed. For the superconducting phase the superfluid density was calculated from μ SR data. The temperature dependence of the superfluid density and the magnetic penetration depth is well described by a multi-gap scenario. In addition the electronic contribution the specific heat was studied for different compositions and magnetic fields and reveals a high value for the Sommerfeld coefficient γ .

  12. Scintillation properties of Eu-doped CsCl and CsBr crystals

    Science.gov (United States)

    Saeki, Keiichiro; Koshimizu, Masanori; Fujimoto, Yutaka; Yanagida, Takayuki; Okada, Go; Yahaba, Takuma; Tanaka, Hironori; Asai, Keisuke

    2016-11-01

    Eu-doped CsCl and CsBr crystals were grown by the vertical Bridgman-Stockbarger method and the scintillation properties of the crystals were investigated. The radioluminescence (RL) bands of CsCl:Eu were observed at 245-270 nm and 450 nm. The former bands are attributed to Auger-free luminescence, and the latter band is attributed to Eu2+ 5d-4f transitions. CsBr:Eu showed an RL band at 435 nm, and this broad band is attributed to Eu2+ 5d-4f transitions. The scintillation decay-time constants of the slow components for CsCl:Eu and CsBr:Eu were 0.38 and 2.8 μs, respectively. Based on the pulse-height spectra for 662 keV gamma ray from 137Cs, the light yield of CsCl:Eu and CsBr:Eu are estimated to be 1700 and 2500 photons/MeV, respectively.

  13. DFT modeling on the suitable crown ether architecture for complexation with Cs⁺ and Sr²⁺ metal ions.

    Science.gov (United States)

    Boda, Anil; Ali, Sk Musharaf; Shenoi, Madhav R K; Rao, Hanmanth; Ghosh, Sandip K

    2011-05-01

    Crown ether architectures were explored for the inclusion of Cs(+) and Sr(2+) ions within nano-cavity of macrocyclic crown ethers using density functional theory (DFT) modeling. The modeling was undertaken to gain insight into the mechanism of the complexation of Cs(+) and Sr(2+) ion with this ligand experimentally. The selectivity of Cs(+) and Sr(2+) ions for a particular size of crown ether has been explained based on the fitting and binding interaction of the guest ions in the narrow cavity of crown ethers. Although, Di-Benzo-18-Crown-6 (DB18C6) and Di-Benzo-21-Crown-7 (DB21C7) provide suitable host architecture for Sr(2+) and Cs(+) ions respectively as the ion size match with the cavity of the host, but consideration of binding interaction along with the cavity matching both DB18C6 and DB21C7 prefers Sr(2+) ion. The calculated values of binding enthalpy of Cs metal ion with the crown ethers were found to be in good agreement with the experimental results. The gas phase binding enthalpy for Sr(2+) ion with crown ether was higher than Cs metal ion. The ion exchange reaction between Sr and Cs always favors the selection of Sr metal ion both in the gas and in micro-solvated systems. The gas phase selectivity remains unchanged in micro-solvated phase. We have demonstrated the effect of micro-solvation on the binding interaction between the metal ions (Cs(+) and Sr(2+)) and the macrocyclic crown ethers by considering micro-solvated metal ions up to eight water molecules directly attached to the metal ion and also by considering two water molecules attached to metal-ion-crown ether complexes. A metal ion exchange reaction involving the replacement of strontium ion in metal ion-crown ether complexes with cesium ion contained within a metal ion-water cluster serves as the basis for modeling binding preferences in solution. The calculated O-H stretching frequency of H(2)O molecule in micro-solvated metal ion-crown complexes is more red-shifted in comparison to hydrated

  14. Determination of gross alpha, 224Ra, 226Ra, and 228Ra activities in drinking water using a single sample preparation procedure.

    Science.gov (United States)

    Parsa, Bahman; Obed, Reynaldo N; Nemeth, William K; Suozzo, Gail P

    2005-12-01

    The current federal and New Jersey State regulations have greatly increased the number of gross alpha and radium tests for public and private drinking water supplies. The determination of radium isotopes in water generally involves lengthy and complicated processes. In this study, a new approach is presented for the determination of gross alpha, 224Ra, 226Ra, and 228Ra activities in water samples. The method includes a single sample preparation procedure followed by alpha counting and gamma-ray spectroscopy. The sample preparation technique incorporates an EPA-approved co-precipitation methodology for gross alpha determination with a few alterations and improvements. Using 3-L aliquots of sample, spiked with 133Ba tracer, the alpha-emitting radionuclides are isolated by a BaSO4 and Fe(OH)3 co-precipitation scheme. First the gross alpha-particle activity of the sample is measured with a low-background gas-flow proportional counter, followed by radium isotopes assay by gamma-ray spectroscopy, using the same prepared sample. Gamma-ray determination of 133Ba tracer is used to assess the radium chemical recovery. The 224Ra, 226Ra, and 228Ra activities in the sample are measured through their gamma-ray-emitting decay products, 212Pb, 214Pb/214Bi, and 228Ac, respectively. In cases where 224Ra determination is required, the gamma-ray counting should be performed within 2-4 d from sample collection. To measure 226Ra activity in the sample, the gamma-ray spectroscopy can be repeated 21 d after sample preparation to ensure that 226Ra and its progeny have reached the equilibrium state. At this point, the 228Ac equilibration with parent 228Ra is already established. Analysis of aliquots of de-ionized water spiked with NIST-traceable 230Th, 224Ra, 226Ra, and 228Ra standards demonstrated the accuracy and precision of this method. Various performance evaluation samples were also assayed for gross alpha as well as radium isotope activity determination using this procedure and the

  15. Raúl Pepe Verano Montesinos

    Directory of Open Access Journals (Sweden)

    José Luis Luque

    2013-05-01

    Full Text Available El 31 de enero de 2005 falleció en Lima el doctor Raúl Verano. Nacido el 12 de julio de 1940 en Cajatambo, realizó sus estudios superiores en la Universidad Nacional Mayor de San Marcos, graduándose en 1971 de bachiller en Educación y en 1972 obtuvo el grado de bachiller en Biología con la tesis Foraminíferos del litoral del departamento de Lima; optando la profesión de Biólogo en 1973. Empezó sus actividades docentes en 1965 como Ayudante de Prácticas en las cá- tedras de zoología y desde 1971 fue Jefe de Prácticas. Ascendiendo a Auxiliar en 1974, para luego ocupar diversos cargos en la administración universitaria, siendo los más destacados el de Director del Instituto de Investigaciones Antonio Raimondi entre 1981 y 1985 y Decano de la Facultad de Ciencias Biológicas de la Universidad Nacional Mayor de San Marcos en el período 1988 a 1991. Sus actividades de investigación estuvieron alrededor de la ictioparasitología, obteniendo el grado de Doctor en Ciencias Biológicas en 1987 con la tesis Kudoa peruviana Mateo, 1972, redescripción y ultraestructura; Kudoa sarmientae sp. n y Kudoa estela sp. n en peces de la costa peruana

  16. Gamma-spectrometric determination of the sup 8 sup 9 Sr isotope half-life

    CERN Document Server

    Popov, Y S; Markushin, M N; Kupriyanov, V N; Timofeev, G A

    2002-01-01

    Using the method of semiconductor [Ge(Li)-detector] gamma-spectroscopy by the results of measurements of 913 keV ( sup 8 sup 9 Sr) gamma-line intensity for 6000 h, using as internal reference the 661.7 keV ( sup 1 sup 3 sup 7 Cs) gamma-line, the value of sup 8 sup 9 Sr isotope half-life has been calculated, which proved to be 1208+-9 h or 50.34+-0.37 days. Error is provided for confidential probability P = 0.95

  17. Rheumatoid Arthritis (RA) associated interstitial lung disease (ILD).

    LENUS (Irish Health Repository)

    O'Dwyer, David N

    2013-10-01

    Rheumatoid Arthritis (RA) is the most common Connective Tissue Disease (CTD) and represents an increasing burden on global health resources. Interstitial lung disease (ILD) has been recognised as a complication of RA but its potential for mortality and morbidity has arguably been under appreciated for decades. New studies have underscored a significant lifetime risk of ILD development in RA. Contemporary work has identified an increased risk of mortality associated with the Usual Interstitial Pneumonia (UIP) pattern which shares similarity with the most devastating of the interstitial pulmonary diseases, namely Idiopathic Pulmonary Fibrosis (IPF). In this paper, we discuss recent studies highlighting the associated increase in mortality in RA-UIP. We explore associations between radiological and histopathological features of RA-ILD and the prognostic implications of same. We emphasise the need for translational research in this area given the growing burden of RA-ILD. We highlight the importance of the respiratory physician as a key stakeholder in the multidisciplinary management of this disorder. RA-ILD focused research offers the opportunity to identify early asymptomatic disease and define the natural history of this extra articular manifestation. This may provide a unique opportunity to define key regulatory fibrotic events driving progressive disease. We also discuss some of the more challenging and novel aspects of therapy for RA-ILD.

  18. MRI comes of age in RA clinical trials

    DEFF Research Database (Denmark)

    Peterfy, Charles; Østergaard, Mikkel; Conaghan, Philip G

    2013-01-01

    The success of modern rheumatoid arthritis (RA) therapies and treatment strategies has led to extended placebo phases being unethical in RA randomised controlled trials (RCTs). Modern trials therefore increasingly involve active comparator designs, and this together with some technical issues has...

  19. Gene expression analysis in RA: towards personalized medicine

    NARCIS (Netherlands)

    Burska, A.N.; Roget, K.; Blits, M.; Gomez, L.; Loo, F.A.J. van de; Hazelwood, L.D.; Verweij, C.L.; Rowe, A.; Goulielmos, G.N.; Baarsen, L.G. van; Ponchel, F.

    2014-01-01

    Gene expression has recently been at the forefront of advance in personalized medicine, notably in the field of cancer and transplantation, providing a rational for a similar approach in rheumatoid arthritis (RA). RA is a prototypic inflammatory autoimmune disease with a poorly understood etiopathog

  20. RA – beskeden genetisk disposition - resultater fra nyt dansk tvillingstudie

    DEFF Research Database (Denmark)

    Svendsen, Anders Jørgen

    2010-01-01

    Vi har nu indsamlet data fra en velkarakteriseret kohorte af danske tvillinger med RA, og med den tilhørende biobank-data åbner det mulighed for videre forskning i både genetiske, epigenetiske og miljømæssige forholds betydning for udvikling af RA. De første resultater fra denne udvidede danske u...

  1. 226Ra determination in phosphogypsum by alpha-particle spectrometry

    Science.gov (United States)

    Aguado, J. L.; Bolívar, J. P.; García-Tenorio, R.

    1999-01-01

    A radiochemical method for226Ra determination by alpha-particle spectrometry in environmental samples has been developed in our laboratory. The method has been validated by measurements in samples with known concentrations of this radionuclide and it has been applied in studies related to226Ra behaviour in phosphogypsum (the main by-product of producing phosphoric acid from phosphate rocks).

  2. Identification of 90Sr/40K Based on Cherenkov Detector for Recovery from the Fukushima Nuclear Accident

    Science.gov (United States)

    Ito, Hiroshi; Han, Soorim; Kobayashi, Atsushi; Kaneko, Naomi; Kawai, Hideyuki; Tabata, Makoto

    Although five years have passed since the Fukushima nuclear accident of 2011, the local fisheries have yet to recover from its effects. One reason for this situation is the difficulty of measuring the radioactivity owing to 90Sr in seafood. After the accident, the radioactivity due to Cs isotopes in samples was measured with precision, which facilitated the enforcement of the maximum concentration of Cs radioisotopes in food at 100 Bq/kg, as defined by the Ministry of Health, Labour and Welfare in Japan. However, 90Sr is more dangerous than Cs isotopes because it has an effective half-life of 18 years and accumulates in the bone. The radioactivity owing to 90Sr in a sample is difficult to measure because the beta rays from 137Cs or 40K also contribute to the signal. When measured based on the endpoint pulse height as determined by a conventional survey meter, the beta ray signal from 90Y (daughter of 90Sr) cannot be differentiated from the beta rays from other sources. To overcome this difficulty, in this study, we develop a Cherenkov detector based on a silica aerogel with a refractive index of 1.034 that can identify beta rays from 90Y within a background of beta rays from 137Cs and 40K. This instrument involves a detector that is sensitive to beta rays from 90Sr but less sensitive to radiation from other sources. This detector comprises a trigger counter that uses scintillating fibers, an aerogel Cherenkov counter with wavelength-shifting fibers, and a veto counter to suppress cosmic rays. We characterize the detector using a 90Sr source, 137Cs source, and pure potassium chloride reagent of 16.6 Bq/g, where the radioactivity of natural 40K is estimated to be 31.7 Bq/g. The following results are obtained: the absolute detection efficiency for 90Sr, 137Cs, and 40K is [2.24 ± 0.01 (stat) ± 0.44 (sys)] × 10-3 Bq-1 s-1, [1.27 ± 0.08 (stat) ± 0.25 (sys)] × 10-6 Bq-1 s-1, and [5.05 ± 2.40 (stat) ± 0.15 (sys)] × 10-5 Bq-1 s-1, respectively. To aid in the

  3. Radium Ra 223 dichloride in castration-resistant prostate cancer.

    Science.gov (United States)

    Joung, J Y; Ha, Y S; Kim, I Y

    2013-08-01

    Radium Ra 223 dichloride (Xofigo®, formerly Alpharadin) is one of the representative α-particle-emitting isotopes that delivers radiation with a higher biological effect to a more localized area. Preclinical studies in mouse, rat and canine models have demonstrated that radium Ra 223 dichloride has a definite skeletal affinity and antitumor effect with a relatively low toxicity on bone marrow. More recently, in a large randomized phase III trial (ALSYMPCA), patients with bone metastasis and castration-resistant prostate cancer (CRPC) received six cycles of 50 kBq/kg of radium Ra 223 dichloride in 4-week intervals. In these men, radium Ra 223 dichloride improved the median overall survival by 3.6 months when compared to the placebo group. Collectively, these results suggest that radium Ra 223 dichloride is a promising candidate for managing bone metastases in patients with CRPC. Copyright 2013 Prous Science, S.A.U. or its licensors. All rights reserved.

  4. THE IMMUNOLOGICAL CHARACTERISTIC OF RA PATIENTS WITH ANAEMIA

    Directory of Open Access Journals (Sweden)

    A. E. Sizikov

    2014-07-01

    Full Text Available Abstract. The aim of the investigation was to study the immunological characteristics of RA patients with anaemia. Clinical and laboratory data including the percentage of the main lymphocyte subclasses, phagocyte and DTH-effector activity, serum concentration of immunoglobulins, the percentage of cells producing IFNγ and/or IL-4 and percent of monocytes producing TNF. We revealed some significant clinical, laboratory and immunological differences between RA patients and healthy donors and between patients with and without anaemia. Our data demonstrate RA anemic patients to have more severe disorders than patients without anaemia. We also revealed some significant immunological differences between RA patients and healthy donors and between patients with and without anaemia, including percent of cells producing IFNγ and/or IL-4. Our data permit to conclude that RA patients have many different immunological disturbances, more severe in anaemic patients.

  5. Recovery of Ra-223 from natural thorium irradiated by protons

    Energy Technology Data Exchange (ETDEWEB)

    Vasiliev, Aleksandr N.; Ostapenko, Valentina S. [Lomonosov Moscow State Univ. (Russian Federation); Russian Academy of Sciences, Moscow-Troitsk (Russian Federation). Inst. for Nuclear Research; Lapshina, Elena V.; Ermolaev, Stanislav V.; Zhuikov, Boris L. [Russian Academy of Sciences, Moscow-Troitsk (Russian Federation). Inst. for Nuclear Research; Danilov, Sergey S. [Lomonosov Moscow State Univ. (Russian Federation); Kalmykov, Stepan N. [Lomonosov Moscow State Univ. (Russian Federation); National Research Center ' Kurchatov Institute' (NRC ' Kurchatov Institute' ), Moscow (Russian Federation)

    2016-11-01

    Irradiation of natural thorium with medium-energy protons is considered to be a prospective approach to large-scale production of {sup 225}Ac and {sup 223}Ra. In addition to the earlier-developed method of {sup 225}Ac isolation, the present work focuses on the simultaneous recovery of {sup 223}Ra from the same thorium target. Radiochemical procedure is based on liquid-liquid extraction, cation exchange and extraction chromatography. The procedure provides separation of radium from spallation and fission products generated in the thorium target. High chemical yield (85-90%) and radionuclide purity of {sup 223}Ra (> 99.8% except {sup 224}Ra and {sup 225}Ra isotopes) have been achieved.

  6. The effective and environmental half-life of {sup 137}Cs at Coral Islands at the former US nuclear test site

    Energy Technology Data Exchange (ETDEWEB)

    Robison, William L. E-mail: robison1@llnl.gov; Conrado, Cynthia L.; Bogen, Kenneth T.; Stoker, A. Carol

    2003-07-01

    The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 ({sup 137}Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of {sup 137}Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of {sup 137}Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of {sup 137}Cs and {sup 90}Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of {sup 137}Cs and {sup 90}Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of {sup 137}Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the {sup 137}Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the {sup 137}Cs/{sup 90}Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the {sup 137}Cs/{sup 90}Sr ratios in soil in 1987 relative to the{sup 137}Cs/{sup 90}Sr ratios at the time of deposition in 1954 is less

  7. Synthesis and Microstructure of Partly-oriented Bismuth Layer Structure Ferroelectrics Ceramics SrBi4Ti4O15

    Institute of Scientific and Technical Information of China (English)

    HAO Hua; LIU Hanxing; OUYANG Shixi

    2005-01-01

    SrBi4Ti4O15 powder was synthesized by conventional solid state synthesis (CS) and molten salt synthesis (MSS). MSS method can synthesize plate-like SrBi4Ti4O15 at lower temperature ( 900℃ ) than CS method. Plate- like form becomes more distinct when the synthesis temperature increases. This would help cause the grain orientation of the ceramics after sintering. The sintered samples of MSS had grain orientation at (0,0,10) plane. The degree of (0,0,10) grain orientation F was 62.1%. Hot pressing made (0,0,10) grain orientation more distinct ( F = 85.7% ). The microstructures of the sintered samples were detected by SEM. Due to the grain orientation, the density of samples fabricated by MSS was lower than that of prepared by CS.

  8. VERA-CS Verification & Validation Plan

    Energy Technology Data Exchange (ETDEWEB)

    Downar, Thomas [Univ. of Michigan, Ann Arbor, MI (United States)

    2017-02-01

    This report summarizes the current status of VERA-CS Verification and Validation for PWR Core Follow operation and proposes a multi-phase plan for continuing VERA-CS V&V in FY17 and FY18. The proposed plan recognizes the hierarchical nature of a multi-physics code system such as VERA-CS and the importance of first achieving an acceptable level of V&V on each of the single physics codes before focusing on the V&V of the coupled physics solution. The report summarizes the V&V of each of the single physics codes systems currently used for core follow analysis (ie MPACT, CTF, Multigroup Cross Section Generation, and BISON / Fuel Temperature Tables) and proposes specific actions to achieve a uniformly acceptable level of V&V in FY17. The report also recognizes the ongoing development of other codes important for PWR Core Follow (e.g. TIAMAT, MAMBA3D) and proposes Phase II (FY18) VERA-CS V&V activities in which those codes will also reach an acceptable level of V&V. The report then summarizes the current status of VERA-CS multi-physics V&V for PWR Core Follow and the ongoing PWR Core Follow V&V activities for FY17. An automated procedure and output data format is proposed for standardizing the output for core follow calculations and automatically generating tables and figures for the VERA-CS Latex file. A set of acceptance metrics is also proposed for the evaluation and assessment of core follow results that would be used within the script to automatically flag any results which require further analysis or more detailed explanation prior to being added to the VERA-CS validation base. After the Automation Scripts have been completed and tested using BEAVRS, the VERA-CS plan proposes the Watts Bar cycle depletion cases should be performed with the new cross section library and be included in the first draft of the new VERA-CS manual for release at the end of PoR15. Also, within the constraints imposed by the proprietary nature of plant data, as many as possible of the FY17

  9. DISTRIBUITION OF 226Ra AND 228Ra IN UNDERGROUND WATER INTO THE SOUTH REGION OF SAO PAULO STATE

    Directory of Open Access Journals (Sweden)

    CARVALHO DE JESUS, Sueli; CHIRINOS, Hugo;

    2011-08-01

    Full Text Available Monitor of natural radionuclides in aquatic raw is very important to guaranty the normal control level inthe environmental medium and the human. In this report were available the concentration of 226Ra and 228Ra inCananeia’s underground water, Iguape and Comprida Island into the south region of Sao Paulo state, by grossalpha and beta counting method. The concentration of 226Ra was variety into the interval 0.80 to 23 mBqL-1 inApril/2009 (rain period and into the interval 0.63 to 12 mBqL -1in August/2009 (dried period. The concentrationof 228Ra was variety into the interval 18 to 39 mBqL-1 in April/2009 and into the interval 15 to 72 mBqL-1 inAugust/2009. The Activities ratio of 228Ra/226Ra was variety into the interval 3.3 to 31.7 at rain period and 1.1 to26.7 at dried period. To compare the yield values of 226Ra and 228Ra these show high activity of the 228Raisotope. The calculate dose no arising the reference of effective dose level available by WHO.

  10. Relative injectivity and CS-modules

    Directory of Open Access Journals (Sweden)

    Mahmoud Ahmed Kamal

    1994-01-01

    Full Text Available In this paper we show that a direct decomposition of modules M⊕N, with N homologically independent to the injective hull of M, is a CS-module if and only if N is injective relative to M and both of M and N are CS-modules. As an application, we prove that a direct sum of a non-singular semisimple module and a quasi-continuous module with zero socle is quasi-continuous. This result is known for quasi-injective modules. But when we confine ourselves to CS-modules we need no conditions on their socles. Then we investigate direct sums of CS-modules which are pairwise relatively inective. We show that every finite direct sum of such modules is a CS-module. This result is known for quasi-continuous modules. For the case of infinite direct sums, one has to add an extra condition. Finally, we briefly discuss modules in which every two direct summands are relatively inective.

  11. Diffusivities of Ag, Cs, Sr, and Kr in TRISO fuel particles and graphite

    Energy Technology Data Exchange (ETDEWEB)

    Collin, Blaise Paul [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    Tri-structural isotropic (TRISO) coated particles have been developed and studied since the late 1950s when the concept of coated particles was invented by Roy Huddle of the United Kingdom Atomic Energy Authority. Several decades of work by half a dozen countries on fission product transport in TRISO fuel through numerous irradiation and heating experiments have led to several recommendations of transport data and to the adoption of various sets of diffusion coefficients. In 1997, the International Atomic Energy Agency (IAEA) gathered all these historical results and issued a technical document (TECDOC-978 [IAEA]) that summarizes these sets of recommended diffusion coefficients. Table 1 shows the reference literature articles for the diffusivities that have historically been recommended by the American and German TRISO fuel development programs and that are summarized in the IAEA report (see section 7 for full references of these articles).

  12. CS Unplugged and Middle-School Students' Views, Attitudes, and Intentions regarding CS

    Science.gov (United States)

    Taub, Rivka; Armoni, Michal; Ben-Ari, Mordechai

    2012-01-01

    Many students hold incorrect ideas and negative attitudes about computer science (CS). In order to address these difficulties, a series of learning activities called Computer Science Unplugged was developed by Tim Bell and his colleagues. These activities expose young people to central concepts in CS in an entertaining way without requiring a…

  13. Dispersion and fate of {sup 90}Sr in the Northwestern Pacific and adjacent seas: Global fallout and the Fukushima Dai-ichi accident

    Energy Technology Data Exchange (ETDEWEB)

    Maderich, V., E-mail: vladmad@gmail.com [Institute of Mathematical Machine and System Problems, Glushkov av., 42, Kiev 03187 (Ukraine); Jung, K.T., E-mail: ktjung@kiost.ac [Korea Institute of Ocean Science and Technology, 787, Haean-ro, Ansan 426-744 (Korea, Republic of); Bezhenar, R., E-mail: romanbezhenar@gmail.com [Ukrainian Center of Water and Environmental Projects, Glushkov av., 42, Kiev 03187 (Ukraine); With, G. de, E-mail: g.dewith@nrg.eu [NRG, Utrechtseweg 310, 6800 ES Arnhem (Netherlands); Qiao, F., E-mail: qiaofl@fio.org.cn [First Institute of Oceanography, 6 Xianxialing Road, Qingdao 266061 (China); Casacuberta, N., E-mail: ncasacuberta@phys.ethz.ch [Laboratory of Ion Beam Physics, ETH-Zurich, Schafmattstrasse 20, 8093 Zurich (Switzerland); Masque, P., E-mail: pere.masque@uab.cat [Institut de Ciència i Tecnologia Ambientals and Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra (Spain); Kim, Y.H., E-mail: yhkimstar@gmail.com [Korea Institute of Ocean Science and Technology, 787, Haean-ro, Ansan 426-744 (Korea, Republic of)

    2014-10-01

    The 3D compartment model POSEIDON-R was applied to the Northwestern Pacific and adjacent seas to simulate the transport and fate of {sup 90}Sr in the period 1945–2010 and to perform a radiological assessment on the releases of {sup 90}Sr due to the Fukushima Dai-ichi nuclear accident for the period 2011–2040. The contamination due to runoff of {sup 90}Sr from terrestrial surfaces was taken into account using a generic predictive model. A dynamical food-chain model describes the transfer of {sup 90}Sr to phytoplankton, zooplankton, molluscs, crustaceans, piscivorous and non-piscivorous fishes. Results of the simulations were compared with observation data on {sup 90}Sr for the period 1955–2010 and the budget of {sup 90}Sr activity was estimated. It was found that in the East China Sea and Yellow Sea the riverine influx was 1.5% of the ocean influx and it was important only locally. Calculated concentrations of {sup 90}Sr in water, bottom sediment and marine organisms before and after the Fukushima Dai-ichi accident are in good agreement with available experimental measurements. The concentration of {sup 90}Sr in seawater would return to the background levels within one year after leakages were stopped. The model predicts that the concentration of {sup 90}Sr in fish after the Fukushima Dai-ichi accident shall return to the background concentrations only 2 years later due to the delay of the transfer throughout the food web and specific accumulation of {sup 90}Sr. The contribution of {sup 90}Sr to the maximal dose rate due to the FDNPP accident was three orders of magnitude less than that due to {sup 137}Cs, and thus well below the maximum effective dose limits for the public. - Highlights: • A box model with a dynamical food-chain model for the NW Pacific was applied. • The transport and fate of {sup 90}Sr in sea were simulated for the period 1945–2040. • Marine exposure pathways for {sup 90}Sr were assessed for the Fukushima Dai-ichi accident.

  14. Sr and Nd isotopic and trace element compositions of Quaternary volcanic centers of the southern Andes

    Energy Technology Data Exchange (ETDEWEB)

    Futa, Kiyoto; Stern, C.R.

    1988-05-01

    Isotopic compositions of samples from six Quaternary volcanoes located in the northern and southern extremities of the Southern Volcanic Zone (SVZ, 33-46/sup 0/S) of the Andes and from four centers in the Austral Volcanic Zone (AVZ, 49-54/sup 0/S) range for /sup 87/Sr//sup 86/Sr from 0.70280 to 0.70591 and for /sup 143/Nd//sup 144/Nd from 0.51314 to 0.51255. Basalts and basaltic andesites from three centers just north of the Chile Rise-Trench triple junction have /sup 87/Sr//sup 86/Sr, /sup 143/Nd//sup 144/Nd, La/Yb, Ba/La and Hf/Lu that lie within the relatively restricted ranges of the basic magmas erupted from the volcanic centers as far north as 35/sup 0/S in the SVZ of the Andes. The trace element and Sr and Nd isotopic characteristics of these magmas may be explained by source region contamination of subarc asthenosphere, with contaminants derived from subducted pelagic sediments and seawater-altered basalts by dehydration of subducted oceanic lithosphere. In the northern extremity of the SVZ between 33/sup 0/ and 34/sup 0/S, basaltic andesites and andesites have higher /sup 87/Sr//sup 86/Sr, Rb/Cs, and Hf/Lu, and lower /sup 143/Nd//sup 144/Nd than basalts and basaltic andesites erupted farther south in the SVZ, which suggests involvement of components derived from the continental crust. In the AVZ, the most primitive sample, high-Mg andesite from the southernmost volcanic center in the Andes (54/sup 0/S) has Sr and Nd isotopic compositions and K/Rb and Ba/La similar to MORB. The high La/Yb of this sample suggests formation by small degrees of partial melting of subducted MORB with garnet as a residue. Samples from centers farther north in the AVZ show a regionally regular northward increase in SiO/sub 2/, K/sub 2/O, Rb, Ba, Ba/La, and /sup 87/Sr//sup 86/Sr and decrease in MgO, Sr, K/Rb, Rb/Cs, and /sup 143/Nd//sup 144/Nd, suggesting increasingly greater degrees of fractional crystallization and associated intra-crustal contamination. (orig./SHOE).

  15. Sr and Nd isotopic and trace element compositions of Quaternary volcanic centers of the Southern Andes

    Science.gov (United States)

    Futa, K.; Stern, C.R.

    1988-01-01

    Isotopic compositions of samples from six Quaternary volcanoes located in the northern and southern extremities of the Southern Volcanic Zone (SVZ, 33-46??S) of the Andes and from four centers in the Austral Volcanic Zone (AVZ, 49-54??S) range for 87Sr 86Sr from 0.70280 to 0.70591 and for 143Nd 144Nd from 0.51314 to 0.51255. The ranges are significantly greater than previously reported from the southern Andes but are different from the isotopic compositions of volcanoes in the central and northern Andes. Basalts and basaltic andesites from three centers just north of the Chile Rise-Trench triple junction have 87Sr 86Sr, 143Nd 144Nd, La Yb, Ba La, and Hf Lu that lie within the relatively restricted ranges of the basic magmas erupted from the volcanic centers as far north as 35??S in the SVZ of the Andes. The trace element and Sr and Nd isotopic characteristics of these magmas may be explained by source region contamination of subarc asthenosphere, with contaminants derived from subducted pelagic sediments and seawater-altered basalts by dehydration of subducted oceanic lithosphere. In the northern extremity of the SVZ between 33?? and 34??S, basaltic andesites and andesites have higher 87Sr 86Sr, Rb Cs, and Hf Lu, and lower 143Nd 144Nd than basalts and basaltic andesites erupted farther south in the SVZ, which suggests involvement of components derived from the continental crust. In the AVZ, the most primitive sample, high-Mg andesite from the southernmost volcanic center in the Andes (54??S) has Sr and Nd isotopic compositions and K Rb and Ba La similar to MORB. The high La Yb of this sample suggests formation by small degrees of partial melting of subducted MORB with garnet as a residue. Samples from centers farther north in the AVZ show a regionally regular northward increase in SiO2, K2O, Rb, Ba, Ba La, and 87Sr 86Sr and decrease in MgO, Sr, K Rb, Rb Cs, and 143Nd 144Nd, suggesting increasingly greater degrees of fractional crystallization and associated intra

  16. The Photoshop CS4 Companion for Photographers

    CERN Document Server

    Story, Derrick

    2009-01-01

    "Derrick shows that Photoshop can be friendly as well as powerful. In part, he does that by focusing photographers on the essential steps of an efficient workflow. With this guide in hand, you'll quickly learn how to leverage Photoshop CS4's features to organize and improve your pictures."-- John Nack, Principal Product Manager, Adobe Photoshop & BridgeMany photographers -- even the pros -- feel overwhelmed by all the editing options Photoshop provides. The Photoshop CS4 Companion for Photographers pares it down to only the tools you'll need most often, and shows you how to use those tools as

  17. Phonon dispersion curves of CsCN

    Indian Academy of Sciences (India)

    N K Gaur; Preeti Singh; E G Rini; Jyotsna Galgale; R K Singh

    2004-08-01

    The motivation for the present work was gained from the recent publication on phonon dispersion curves (PDCs) of CsCN from the neutron scattering technique. We have applied the extended three-body force shell model (ETSM) by incorporating the effect of coupling between the translation modes and the orientation of cyanide molecules for the description of phonon dispersion curves of CsCN between the temperatures 195 and 295 K. Our results on PDCs in symmetric direction are in good agreement with the experimental data measured with inelastic neutron scattering technique.

  18. Mastering Adobe Premiere Pro CS6

    CERN Document Server

    Ekert, Paul

    2013-01-01

    Designed to be practical and engaging, Mastering Adobe Premiere Pro CS6 is a project-based book to help you truly augment your skills and become a film editing hotshot.If you're just starting out or even migrating from existing video editing software, then this book is for you. With rapid progression through practical examples constructed to be both engaging and useful, Mastering Adobe Premiere Pro CS6 is ideal for learning the sometimes complex workflows of this powerful application.

  19. Photoshop CS4 The Missing Manual

    CERN Document Server

    Snider, Lesa

    2009-01-01

    Photoshop is the world's most widely used photo-editing and graphics program. But with all its fantastic new features and options, the CS4 version can bewilder even the most seasoned professional. That's where Photoshop CS4: The Missing Manual comes in: packed with tips, tricks, and lots of practical advice, this visually rich four-color guidebook teaches you everything you need to know to edit photos and create beautiful documents in Photoshop. Whether you're an absolute beginner or a power user ready to try some advanced techniques, author and graphics pro Lesa Snider King offers crystal-c

  20. Study of the 137Cs Stabilizer Source

    Directory of Open Access Journals (Sweden)

    GAO Yan;WANG Yan-ling;XU Zhi-jian;XU Liang;REN Chun-xia;TAN Xiao-ming;CUI Hong-qi

    2014-02-01

    Full Text Available The attenuation laws of the Cesium -137 γ-ray penetrating the ceramic core、stainless steel and tungsten steel were studied. The radioactivity of the 137Cs stabilizer source was determined through the surface dose rate of 137Cs stabilizer sources. In addition, the adsorption properties of the ceramic core were studied to improve the stability of the output rate, and established a production line. The application results showed that the output rate of ray source was accurate and was of a good consistency. At present, the source had been used in logging lithology, and achieved the realization of domestic product.

  1. Ra: The Sun for Science and Humanity

    Science.gov (United States)

    1996-01-01

    To guide the development of the Ra Strategic Framework, we defined scientific and applications objectives. For our primary areas of scientific interest, we choose the corona, the solar wind, the Sun's effect on the Earth, and solar theory and model development. For secondary areas of scientific interest, we selected sunspots, the solar constant, the Sun's gravitational field, helioseismology and the galactic cosmic rays. We stress the importance of stereoscopic imaging, observations at high spatial, spectral, and temporal resolutions, as well as of long duration measurements. Further exploration of the Sun's polar regions is also important, as shown already by the Ulysses mission. From an applications perspective, we adopted three broad objectives that would derive complementary inputs for the Strategic Framework. These were to identify and investigate: possible application spin-offs from science missions, possible solar-terrestrial missions dedicated to a particular application, and possible future applications that require technology development. The Sun can be viewed as both a source of resources and of threats. Our principal applications focus was that of threat mitigation, by examining ways to improve solar threat monitoring and early warning systems. We compared these objectives to the mission objectives of past, current, and planned international solar missions. Past missions (1962-1980) seem to have been focused on improvement of scientific knowledge, using multiple instrument spacecraft. A ten year gap followed this period, during which the results from previous missions were analyzed and solar study programmes were prepared in international organizations. Current missions (1990-1996) focus on particular topics such as the corona, solar flares, and coronal mass ejections. In planned missions, Sun/Earth interactions and environmental effects of solar activity are becoming more important. The corona is the centre of interest of almost all planned missions

  2. Leaching of 226Ra from components of uranium mill tailings

    Science.gov (United States)

    Landa, E.R.

    1991-01-01

    A sequential extraction procedure was used to characterize the geochemical forms of 226Ra retained by mixtures of quartz sand and a variety of fine-grained rock and mineral species. These mixtures had previously been exposed to the sulfuric acid milling liquor of a simulated acid-leach uranium milling circuit. For most test cases, the major fraction of the 226Ra was extracted with 1 mol/1 NH4Cl and was deemed to be exchangeable. However, 226Ra retained by the barite-containing mixture was resistant to both 1 mol/1 NH4Cl and 1 mol/HCHCl extraction. ?? 1991.

  3. Pulmonary cryptococcosis in rheumatoid arthritis (RA) patients: Comparison of imaging characteristics among RA, acquired immunodeficiency syndrome, and immunocompetent patients

    Energy Technology Data Exchange (ETDEWEB)

    Yanagawa, Noriyo, E-mail: noriyo_yana@ybb.ne.jp [Departments of Radiology, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, 3-8-22, Honkomagome, Bunkyo-ku, Tokyo 113-8677 (Japan); Sakai, Fumikazu [Department of Diagnostic Radiology, Saitama Medical University International Medical Center, 1397-1 Yamane, Hidaka-shi, Saitama 350-1298 (Japan); Takemura, Tamiko [Department of Pathology, Japanese Red Cross Medical Center, 4-1-22 Hiroo, Shibuya-ku, Tokyo 150-8935 (Japan); Ishikawa, Satoru [Department of Respiratory Medicine, National Hospital Organization Chiba-East-Hospital, 673 Nitona-cho, Chuo-ku, Chiba-shi, Chiba 260-8712 (Japan); Takaki, Yasunobu [Departments of Radiology, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, 3-8-22, Honkomagome, Bunkyo-ku, Tokyo 113-8677 (Japan); Hishima, Tsunekazu [Department of Pathology, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, 3-8-22, Honkomagome, Bunkyo-ku, Tokyo 113-8677 (Japan); Kamata, Noriko [Departments of Radiology, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, 3-8-22, Honkomagome, Bunkyo-ku, Tokyo 113-8677 (Japan)

    2013-11-01

    Purpose: The imaging characteristics of cryptococcosis in rheumatoid arthritis (RA) patients were analyzed by comparing them with those of acquired immunodeficiency syndrome (AIDS) and immunocompetent patients, and the imaging findings were correlated with pathological findings. Methods: Two radiologists retrospectively compared the computed tomographic (CT) findings of 35 episodes of pulmonary cryptococcosis in 31 patients with 3 kinds of underlying states (10 RA, 12 AIDS, 13 immunocompetent), focusing on the nature, number, and distribution of lesions. The pathological findings of 18 patients (8 RA, 2 AIDS, 8 immunocompetent) were analyzed by two pathologists, and then correlated with imaging findings. Results: The frequencies of consolidation and ground glass attenuation (GGA) were significantly higher, and the frequency of peripheral distribution was significantly lower in the RA group than in the immunocompetent group. Peripheral distribution was less common and generalized distribution was more frequent in the RA group than in the AIDS group. The pathological findings of the AIDS and immunocompetent groups reflected their immune status: There was lack of a granuloma reaction in the AIDS group, and a complete granuloma reaction in the immunocompetent group, while the findings of the RA group varied, including a complete granuloma reaction, a loose granuloma reaction and a hyper-immune reaction. Cases with the last two pathologic findings were symptomatic and showed generalized or central distribution on CT. Conclusion: Cryptococcosis in the RA group showed characteristic radiological and pathological findings compared with the other 2 groups.

  4. 90Sr liquid scintillation urine analysis utilizing different approaches for tracer recovery.

    Energy Technology Data Exchange (ETDEWEB)

    Piraner, Olga; Preston, Rose T.; Shanks, Sonoya Toyoko; Jones, Robert

    2010-08-01

    90Sr is one of the isotopes most commonly produced by nuclear fission. This medium lived isotope presents serious challenges to radiation workers, the environment, and following a nuclear event, the general public. Methods of identifying this nuclide have been in existence for a number of years (e.g. Horwitz, E.P. [1], Maxwell, S.L.[2], EPA 905.0 [3]) which are time consuming, requiring a month or more for full analysis. This time frame is unacceptable in the present security environment. It is therefore important to have a dependable and rapid method for the determination of Sr. The purposes of this study are to reduce analysis time to less than half a day by utilizing a single method of radiation measurement while continuing to yield precise results. This paper presents findings on three methods that can meet this criteria; (1) stable Sr carrier, (2) 85Sr by gamma spectroscopy, and (3) 85Sr by LSC. Two methods of analyzing and calculating the 85Sr tracer recovery were investigated (gamma spectroscopy and a low energy window-Sr85LEBAB by LSC) as well as the use of two different types of Sr tracer (85Sr and stable Sr carrier). Three separate stock blank urine samples were spiked with various activity levels of 239Pu, 137Cs, 90Sr /90Y to determine the effectiveness of the Eichrome Sr-spec resin 2mL extractive columns. The objective was to compare the recoveries of 85Sr versus a stable strontium carrier, attempt to compare the rate at which samples can be processed by evaluating evaporation, neutralization, and removing the use of another instrument (gamma spectrometer) by using the LSC spectrometer to obtain 85Sr recovery. It was found that when using a calibration curve comprised of a different cocktail and a non-optimum discriminator setting reasonable results (bias of « 25%) were achieved. The results from spiked samples containing 85Sr demonstrated that a higher recovery is obtained when using gamma spectroscopy (89-95%) than when using the LEB window

  5. Flash CS4: The Missing Manual

    CERN Document Server

    Grover, Chris

    2008-01-01

    Unlock the power of Flash and bring gorgeous animations to life onscreen. Flash CS4: The Missing Manual includes a complete primer on animation, a guided tour of the program's tools and capabilities, lots of new illustrations, and more details on working with video. Beginners will learn to use the software in no time, and experienced Flash designers will improve their skills.

  6. Atmospheric oxidation of carbon disulfide (CS2)

    Science.gov (United States)

    Zeng, Zhe; Altarawneh, Mohammednoor; Dlugogorski, Bogdan Z.

    2017-02-01

    This contribution investigates primary steps governing the OH-initiated atmospheric oxidation of CS2. Our approach comprises high-level density functional theory calculation of energies and optimisation of molecular structures as well as RRKM-ME analysis for estimating pressure-dependent reaction rate constants. We find the overall reaction OH + CS2 → OCS + SH too slow to account for the formation of the reported experimental products. The initial reaction of OH with CS2 proceeds to produce an S-adduct, SCS(OH). Species-formation history for the system OH + CS2 indicates that, the S-adduct represents the most plausible product with a barrier-less addition process and a stability amounting to 48.5 kJ/mol, in reference to the separated reactants. This adduct then undergoes a bimolecular reaction with atmospheric O2 yielding OCS and HOSO, rather than dissociating back into its separated reactants. We also find that further atmospheric oxidation of the C-adduct (if formed) yields two of the major experimental products namely OCS and SO2. The kinetic analysis provided in this study explains the atmospheric fate of reduced sulfur species, an important S-bearing group in the global cycle of sulfur.

  7. Cesium leaching from {gamma}-irradiated CsA and CsX zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Enrique [Universidad Autonoma Metropolitana, Iztapalapa, A. P. 55-532, Av. San Rafael Atlixco No. 186 Col. Vicentina, 09340 Mexico, D.F. (Mexico)], E-mail: lima@xanum.uam.mx; Ibarra, Ilich A.; Lara, Victor [Universidad Autonoma Metropolitana, Iztapalapa, A. P. 55-532, Av. San Rafael Atlixco No. 186 Col. Vicentina, 09340 Mexico, D.F. (Mexico); Bosch, Pedro [Instituto de Investigaciones en Materiales, A. P. 70-360, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, 04510 Mexico, D.F. (Mexico); Bulbulian, Silvia [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, Col. Escandon, Delegacion Miguel Hidalgo, 11801 Mexico, D.F. (Mexico)

    2008-12-30

    The present study discusses the effect of {gamma}-irradiation on Cs{sup +}-exchanged X and A zeolites. The incorporation of Cs{sup +} ions into A and X zeolites was performed using three different cesium salts (chloride, nitrate or acetate). Cs{sup +} ions immobilized into the vitrified zeolites by thermal treatment are located in different sites of the zeolite networks. It is found that {gamma}-irradiation favors cesium retention depending on the cesium precursor salt used in the cationic exchange step.

  8. Seasonal changes in submarine groundwater discharge to coastal salt ponds estimated using 226Ra and 228Ra as tracers

    Science.gov (United States)

    Hougham, A.L.; Moran, S.B.; Masterson, J.P.; Kelly, R.P.

    2008-01-01

    Submarine groundwater discharge (SGD) to coastal southern Rhode Island was estimated from measurements of the naturally-occurring radioisotopes 226Ra (t1/2 = 1600??y) and 228Ra (t1/2 = 5.75??y). Surface water and porewater samples were collected quarterly in Winnapaug, Quonochontaug, Ninigret, Green Hill, and Pt. Judith-Potter Ponds, as well as nearly monthly in the surface water of Rhode Island Sound, from January 2002 to August 2003; additional porewater samples were collected in August 2005. Surface water activities ranged from 12-83??dpm 100??L- 1 (60??dpm = 1??Bq) and 21-256??dpm 100??L- 1 for 226Ra and 228Ra, respectively. Porewater 226Ra activities ranged from 16-736??dpm 100??L- 1 (2002-2003) and 95-815??dpm 100??L- 1 (2005), while porewater 228Ra activities ranged from 23-1265??dpm 100??L- 1. Combining these data with a simple box model provided average 226Ra-based submarine groundwater fluxes ranging from 11-159??L m- 2 d- 1 and average 228Ra-derived fluxes of 15-259??L m- 2 d- 1. Seasonal changes in Ra-derived SGD were apparent in all ponds as well as between ponds, with SGD values of 30-472??L m- 2 d- 1 (Winnapaug Pond), 6-20??L m- 2 d- 1 (Quonochontaug Pond), 36-273??L m- 2 d- 1 (Ninigret Pond), 29-76??L m- 2 d- 1 (Green Hill Pond), and 19-83??L m- 2 d- 1 (Pt. Judith-Potter Pond). These Ra-derived fluxes are up to two orders of magnitude higher than results predicted by a numerical model of groundwater flow, estimates of aquifer recharge for the study period, and values published in previous Ra-based SGD studies in Rhode Island. This disparity may result from differences in the type of flow (recirculated seawater versus fresh groundwater) determined using each technique, as well as variability in porewater Ra activity. ?? 2007 Elsevier B.V. All rights reserved.

  9. Giver lave Ra-værdier bedre hygiejne?

    DEFF Research Database (Denmark)

    Gram, Lone; Bagge-Ravn, Dorthe; Kold, John;

    2004-01-01

    Ifølge vore undersøgelser er der ingen grund til at ændre på den generelle anbefaling om, at Ra bør være mindre end 0,8 µm. Muligvis kan man dog i særlige tilfælde opnå hygiejnemæssige gevinster ved at bruge meget fine poleringer, dvs. Ra mindre end 0,8 µm.......Ifølge vore undersøgelser er der ingen grund til at ændre på den generelle anbefaling om, at Ra bør være mindre end 0,8 µm. Muligvis kan man dog i særlige tilfælde opnå hygiejnemæssige gevinster ved at bruge meget fine poleringer, dvs. Ra mindre end 0,8 µm....

  10. Tehnikaromud saab peagi tasuta ära anda / Urmas Tooming

    Index Scriptorium Estoniae

    Tooming, Urmas

    2005-01-01

    13. augustist saab vana elektroonikat tasuta ära anda. MTÜ Eesti Elektroonikaromu on juba loonud selleks üle Eesti 44 kogumispunkti, EES-Ringlus ühingus endale konkurenti ei näe. Lisa: Vana tehnika

  11. Cumulative Production Per Township - SaMiRa

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset contains a selected township grid within the Sagebrush Mineral Resource Assessment project (SaMiRa) study area attributed with cumulative oil and gas...

  12. Giver lave Ra-værdier bedre hygiejne?

    DEFF Research Database (Denmark)

    Gram, Lone; Bagge-Ravn, Dorthe; Kold, John

    2004-01-01

    Ifølge vore undersøgelser er der ingen grund til at ændre på den generelle anbefaling om, at Ra bør være mindre end 0,8 µm. Muligvis kan man dog i særlige tilfælde opnå hygiejnemæssige gevinster ved at bruge meget fine poleringer, dvs. Ra mindre end 0,8 µm.......Ifølge vore undersøgelser er der ingen grund til at ændre på den generelle anbefaling om, at Ra bør være mindre end 0,8 µm. Muligvis kan man dog i særlige tilfælde opnå hygiejnemæssige gevinster ved at bruge meget fine poleringer, dvs. Ra mindre end 0,8 µm....

  13. Tehnikaromud saab peagi tasuta ära anda / Urmas Tooming

    Index Scriptorium Estoniae

    Tooming, Urmas

    2005-01-01

    13. augustist saab vana elektroonikat tasuta ära anda. MTÜ Eesti Elektroonikaromu on juba loonud selleks üle Eesti 44 kogumispunkti, EES-Ringlus ühingus endale konkurenti ei näe. Lisa: Vana tehnika

  14. An early "Atkins' Diet": RA Fisher analyses a medical "experiment".

    Science.gov (United States)

    Senn, Stephen

    2006-04-01

    A study on vitamin absorption which RA Fisher analysed for WRG Atkins and co-authored with him is critically examined. The historical background as well as correspondence between Atkins and Fisher is presented.

  15. Research of RA Coding Algorithm Based on AWGN Channel

    Directory of Open Access Journals (Sweden)

    Xianzhong Chen

    2012-04-01

    Full Text Available In order to study the performance of RA, and the impacts of iterations and code length to the compiled code characteristics, we respectively made simulation analysis on RA, LDPC and TURBO with different parameters. We did it by designing code length, rate and iterations to analyze signals to noise ratio changes. With three patterns comparing the simulation analysis, it turned out that volume reaches the limit of Shannon when RA is in the condition of maximum likelihood decoding. The bit error ratio reduces as the message length goes up, and the performance comes near channel capacity. As the iterations increase, and bit error ratio reduces, and the performance will be better. Research shows that RA has more advantages and wide application propects whether in complexity or in performance.

  16. 18-Electron Resonance Structures in the BCC Transition Metals and Their CsCl-type Derivatives.

    Science.gov (United States)

    Vinokur, Anastasiya I; Fredrickson, Daniel C

    2017-03-06

    Bonding in elemental metals and simple alloys has long been thought of as involving intense delocalization, with little connection to the localized bonds of covalent systems. In this Article, we show that the bonding in body-centered cubic (bcc) structures of the group 6 transition metals can in fact be represented, via the concepts of the 18-n rule and isolobal bonding, in terms of two balanced resonance structures. We begin with a reversed approximation Molecular Orbital (raMO) analysis of elemental Mo in its bcc structure. The raMO analysis indicates that, despite the low electron count (six valence electrons per Mo atom), nine electron pairs can be associated with any given Mo atom, corresponding to a filled 18-electron configuration. Six of these electron pairs take part in isolobal bonds along the second-nearest neighbor contacts, with the remaining three (based on the t2g d orbitals) interacting almost exclusively with first-nearest neighbors. In this way, each primitive cubic network defined by the second-nearest neighbor contacts comprises an 18-n electron system with n = 6, which essentially describes the full electronic structure of the phase. Of course, either of the two interpenetrating primitive cubic frameworks of the bcc structure can act as a basis for this discussion, leading us to write two resonance structures with equal weights for bcc-Mo. The electronic structures of CsCl-type variants with the same electron count can then be interpreted in terms of changing the relative weights of these two resonance structures, as is qualitatively confirmed with raMO analysis. This combination of raMO analysis with the resonance concept offers an avenue to extend the 18-n rule into other transition metal-rich structures.

  17. O pensamento desenvolvimentista de Raúl Prebisch Raúl Prebisch's thought on development

    Directory of Open Access Journals (Sweden)

    Joaquim Miguel Couto

    2007-04-01

    Full Text Available As idéias do economista argentino Raúl Prebisch (1901-1986 sempre estiveram voltadas para a ação. As dificuldades encontradas diante de problemas concretos (durante a crise dos anos 1930, tornaram Prebisch um homem prático. Assim, suas teorias sobre a substituição de importações, o sistema centro-periferia e a criação de um mercado comum latino-americano, possuíam um grande sentido de influenciar a realidade. A única exceção coube a sua "Teoria da Transformação", construída no último decênio de sua vida. Nesta, Prebisch se afasta da realidade e teoriza sobre a criação de um novo sistema econômico, através de uma síntese entre socialismo e liberalismo.The Argentinean economist Raúl Prebisch’s (1901-1986 ideas were always gone back to the action. Difficulties facing concrete problems made him a pragmatic man. Thus, his theories about import substitution, core-periphery system and the creation of a common Latin-American market, were embodied in a great purpose of influencing the reality. The only exception was the "Theory of Transformation", which was built in the last decade of this life. There, Prebisch moves off practical matters and speculates about the creation of a new economic system, through a synthesis of socialism and liberalism.

  18. Pharmacologic and economic differentiation of drugs for RA in Italy

    Directory of Open Access Journals (Sweden)

    Patrizia Berto

    2012-07-01

    Full Text Available Rheumatoid arthritis (RA is a chronic, progressive and degenerative illness, which affects about 0.5% of the adult population with significant social costs. In Italy there are approximately 300,000 people with RA, with twice as many women than men. RA causes progressive deformity and disability and is associated with numerous co-morbid conditions that reduce the life expectancy of 5-10 years. The costs of RA have a serious impact on the entire community, especially in terms of disability, hospitalization and medical care. In Italy has been estimated that cost of illness could reach about 1,600 million euros, of which over two thirds are represented by indirect costs. The treatment of RA is evolving and the introduction of biological drugs has resulted in a significant progress in terms of therapeutic possibilities. Etanercept, the only soluble receptor of TNF-alfa currently approved appears to be cost-effective and it is recommended by major guidelines for the treatment of RA.  http://dx.doi.org/10.7175/rhc.v3i3.201

  19. Surface pathway of radioactive plume of TEPCO Fukushima NPP1 released 134Cs and 137Cs

    Directory of Open Access Journals (Sweden)

    M. Aoyama

    2013-05-01

    Full Text Available 134Cs and 137Cs were released to the North Pacific Ocean by two major likely pathways, direct discharge from the Fukushima NPP1 accident site and atmospheric deposition off Honshu Islands of Japan, east and northeast of the site. High density observations of 134Cs and 137Cs in the surface water were carried out by 17 cruises of cargo ships and several research vessel cruises from March 2011 till March 2012. The main body of radioactive surface plume of which activity exceeded 10 Bq m−3 travelled along 40° N and reached the International Date Line on March 2012, one year after the accident. A distinct feature of the radioactive plume was that it stayed confined along 40° N when the plume reached the International Date Line. A zonal speed of the radioactive plume was estimated to be about 8 cm s−1 which was consistent with zonal speeds derived by Argo floats at the region.

  20. Biological availability of (238)U, (234)U and (226)Ra for wild berries and meadow grasses in natural ecosystems of Belarus.

    Science.gov (United States)

    Sokolik, G A; Ovsiannikova, S V; Voinikava, K V; Ivanova, T G; Papenia, M V

    2014-01-01

    This work is devoted to investigation of behavior of (234)U, (238)U and (226)Ra by determining the soil to plant transfer under different natural conditions such as forest or swamped areas and meadow lands with different soil types. The paper summarizes the data on investigation of uranium and radium uptake by wild berries and natural meadow grasses in the typical conditions of Belarus. Parameters characterizing the biological availability of (234)U, (238)U and (226)Ra for bilberry (Vaccinium myrtillus), lingonberry (Vaccinium viti-idaea), blueberry (Vaccinium iliginosum) and cranberry (Vaccinium oxycoccus palustris) as well as for widely occurring mixed meadow vegetation, which belongs to the sedge-grass or grass-sedge associations and forbs, have been established. In the sites under investigation, the deposition levels of (238+239+240)Pu were less than 0.37 kBq m(-2) and (137)Cs deposition ranged between less than 0.37 and 37 kBq m(-2). It was found that activity concentrations of radionuclides in berries varied in the ranges of 0.037-0.11 for (234)U, 0.036-0.10 for (238)U and 0.11-0.43 Bq kg(-1) for (226)Ra, but in the mixed meadow grasses they were 0.32-4.4, 0.24-3.9 and 0.14-6.9 Bq kg(-1) accordingly. The (234)U/(238)U activity ratios were 1.02 ± 0.01 for wild berries, 1.20 ± 0.09 for underground meadow grasses and 1.02 ± 0.02 for proper soils. The concentration ratios (CRs, dry weight basis) of (234)U and (238)U for mixed meadow grasses were 0.036-0.42 and 0.041-0.46 respectively. The correspondent geometric means (GM) were 0.13 and 0.15 with geometric standard deviations (GSD) of 2.4. The CRs of (226)Ra for meadow grasses were 0.031-1.0 with GM 0.20 and GSD 2.6. The CRs of (234)U, (238)U and (226)Ra for wild berries ranged within 0.0018-0.008 (GM is 0.0034, GSD is 1.8), 0.0018-0.008 (GM is 0.0035, GSD is 1.8) and 0.005-0.033 (GM is 0.016, GSD is 2.1) accordingly. The highest CR values of uranium for mixed meadow grasses were found in the

  1. High-Spin States in ~(86)Sr

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The previous works for high spins states of 86Sr were very scarce. In the past, the spin of highest level of 86Sr was 13 found by the reaction 84Kr(α, 2nγ)86Sr in 28 MeV. The current work updates the level scheme of 86Sr to get more information about high spin states in 86Sr.

  2. Application of {sup 137}Cs and {sup 210}Pb radionuclides to determine sedimentation rates of recent sediments from Admiralty Bay, Antarctica Peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Mylene Giseli do; Martins, Cesar de Castro [Universidade Federal do Parana (UFPR), Pontal do Parana, PR (Brazil). Centro de Estudos do Mar (CEM); Figueira, Rubens C.L.; Montone, Rosalinda C.; Mahiques, Michel M. de; Tessler, Moyses G., E-mail: rfigueira@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Inst. Oceanografico. Dept. de Oceanografia Fisica, Quimica e Geologica; Vendrame, Antonio C. [Universidade Cruzeiro do Sul, Sao Paulo, SP (Brazil)

    2009-07-01

    Studies about natural and artificial radionuclides in areas such as the Antarctic are key to understand natural and dynamic processes in marine environments. These studies are important to determine levels of radioactive elements and local sedimentation rates. Five marine sediment cores were collected in different points of Admiralty Bay, in the Antarctic Peninsula. The purpose of this study was to determine {sup 137}Cs, {sup 226}Ra and {sup 210}Pb and sedimentation rates at each site. {sup 137}Cs, {sup 210}Pb and {sup 226}Ra were assayed by gamma-counting through direct measurement of the peak at 661 keV, 47 keV and 609 keV, respectively. Sedimentation rates were obtained by {sup 137}Cs and {sup 210}Pb (CIC and CRS). The activities for {sup 137}Cs ranged from 0.84 to 7.09 Bq kg{sup -1}; to {sup 226}Ra from 6.77 to 31.07 Bq kg{sup -1} for {sup 210}Pb ranged from 1.10 to 36.90 Bq kg{sup -1}. The sedimentation rates obtained by the three models ranged from 0.11+-0.01 cm y{sup -1} to 0.46+-0.05 cm y{sup -1}. The levels of {sup 137}Cs registered in this study, as well as in other studies in the Antarctic region indicate that global fallout is the main cause of artificial radionuclides present in this environment, since the Antarctic has not suffered a direct action of human activities that released radioactive elements. The possible grain size variations that occur in the studied points of Admiralty Bay may explain the differences found in the vertical distribution of radionuclides, because of the different values of sedimentation rates and respective dating determined in their profiles. (author)

  3. Investigation of $\\alpha$-decay rates of $^{221}$Fr, $^{224}$Ra and $^{226}$Ra in different environments

    CERN Multimedia

    2007-01-01

    It has recently been suggested, and indicated experimentally, that $\\alpha$- decay half-lives are modified by solid state effects in the surrounding environment. We propose here to measure with high accuracy the $\\alpha$-decay half-life of $^{221}$Fr, $^{224}$Ra and $^{226}$Ra in insulators and metals. Furthermore we plan to investigate the temperature dependency of the half-life in these materials (room temperature, 4 K and 10 mK).

  4. Coral Sr-U Thermometry

    Science.gov (United States)

    DeCarlo, T. M.; Gaetani, G. A.; Cohen, A. L.; Foster, G. L.; Alpert, A.; Stewart, J.

    2016-12-01

    Coral skeletons archive the past two millennia of climate variability in the oceans with unrivaled temporal resolution. However, extracting accurate temperature information from coral skeletons is confounded by "vital effects", which often override the temperature dependence of geochemical proxies. Here, we present a new approach to coral paleothermometry based on results of abiogenic precipitation experiments interpreted within a framework provided by a quantitative model of the coral biomineralization process. We conducted laboratory experiments to test the temperature and carbonate chemistry controls on abiogenic partitioning of Sr/Ca and U/Ca between aragonite and seawater, and we modeled the sensitivity of skeletal composition to processes occurring at the site of calcification. The model predicts that temperature can be accurately reconstructed from coral skeleton by combining Sr/Ca and U/Ca ratios into a new proxy, Sr-U. We tested the model predictions with measured Sr/Ca and U/Ca ratios of fourteen Porites sp. corals collected from the tropical Pacific Ocean and the Red Sea, with a subset also analyzed using the boron isotope (δ11B) pH proxy. Observed relationships among Sr/Ca, U/Ca, and δ11B agree with model predictions, indicating that the model accounts for the key features of the coral biomineralization process. We calibrated Sr-U to instrumental temperature records and found that it captures 93% of mean annual variability (26-30 °C) and predicts temperature within 0.5 °C (1 σ). Conversely, Sr/Ca alone has an error of prediction of 1 °C and often diverges from observed temperature by 3 °C or more. Many of the problems afflicting Sr/Ca - including offsets among neighboring corals and decouplings from temperature during coral stress events - are reconciled by Sr-U. By accounting for the influence of the coral biomineralization process, the Sr-U thermometer may offer significantly improved reliability for reconstructing ocean temperatures from coral

  5. Modeling the cryosphere with FEniCS

    CERN Document Server

    Cummings, Evan M

    2016-01-01

    This manuscript is a collection of problems and solutions related to modeling the cryosphere using the finite element software FEniCS. Included is an introduction to the finite element method; solutions to a variety of problems in one, two, and three dimensions; an overview of popular stabilization techniques for numerically-unstable problems; and an introduction to the governing equations of ice-sheet dynamics with associated FEniCS implementations. The software developed for this project, Cryospheric Problem Solver (CSLVR), is fully open-source and has been designed with the goal of simplifying many common tasks associated with modeling the cryosphere. CSLVR possesses the ability to download popular geological and geographical data, easily convert between geographical projections, develop sophisticated two- or three-dimensional finite-element meshes, convert data between many popular formats, and produce production-quality images of data. Scripts are presented which model the flow of ice using geometry defi...

  6. Teaching the Five Cs with Cinema

    Directory of Open Access Journals (Sweden)

    Rimma Garn

    2012-08-01

    Full Text Available This paper discusses teaching the five Cs (as noted in the following introduction, delineated in the “National Standards for Foreign Language Learning in the 21st Century,” through a college content course based on cinema. It provides an overview of a 2009 Berkeley workshop, “Teaching Language and Culture with Film,” that addressed larger issues related to such courses within the curriculum, their design and teaching. The paper goes on to describe three Russian courses based on the same textbook, KinoTalk, yet designed for different student audiences: for traditional third year students and for various kinds of non-traditional students, for heritage speakers, and for former missionaries with two-years experience in the target country but minimal formal training in the language. In conclusion, the paper suggests ideas for further courses taught using the same textbook and for teaching the five Cs through language and cinema in general.

  7. CS model coil experimental log book

    Energy Technology Data Exchange (ETDEWEB)

    Nishijima, Gen; Sugimoto, Makoto; Nunoya, Yoshihiko; Wakabayashi, Hiroshi; Tsuji, Hiroshi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    2001-02-01

    Charging test of the ITER CS Model Coil which is the world's largest superconducting pulse coil and the CS Insert Coil had started at April 11, 2000 and had completed at August 18, 2000. In the campaign, total shot numbers were 356 and the size of the data file in the DAS (Data Acquisition System) was over 20 GB. This report is a database that consists of the log list and the log sheets of every shot. One can access the database, make a search, and browse results via Internet (http://1ogwww.naka.jaeri.go.jp). The database will be useful to quick search to choose necessary shots. (author)

  8. Ra-226 and Ra-226/Ba Signatures of Intermediate and Deep Water Masses of the Labrador Sea

    Science.gov (United States)

    Pons-Branchu, E.; Hillaire-Marcel, C.; Ghaleb, B.

    2004-05-01

    The Labrador sea plays an important role in the formation of intermediate North Atlantic water, (cf. Labrador Sea Water -LSW) and subsequently, in the general thermohaline circulation of the ocean. In addition, water masses originating from the Norwegian and Greenland seas are present below the LSW, in the deeper part of the basin. Investigations on the geochemistry of radium have been undertaken as a mean to document these deep and intermediate circulation processes. The vertical distribution of Ra-226 and Ba contents has been established for 8 stations located along 2 sections from 48°44 N; 52°58W to 52°23 N 45°17W and from 53.59°N to 60.34°N, 48.13°W. Thermo-Ionization Mass Spectrometry coupled with a new radium extraction and purification technique permitted the measurement of Ra-226 using 200 ml samples (i.e., appr. 10 femtograms of Ra). In parallel, Ba contents were determined using M-C-ICP-MS in order to normalize Ra-226 concentrations, since Ba is often seen as a subrogate stable isotope of Ra, due to their almost similar geochemical behaviour. Large variations in Ra-226 concentrations are observed. They range from 51 fg/g in intermediate and deep water samples to 31 fg/g in surface waters. When normalised to a salinity of 35 or to the Ba contents large discrepancies are still observed. They suggest a specific Ra-signature for each of the major water masses present in the basin. Particular attention has been paid to Ra-226 contents in the LSW in relation to its production rate as well as to the influence of the Western Boundary Under Current (WBUC), which carries the North Atlantic Deep water masses into their gyre along the lower slopes of the Labrador sea. Based on the presently available data set, a peak in Ra-226 and Ba contents seems to characterise the high velocity axis of the WBUC. These data suggest moreover a lower Ra-226 content for the LSW than for the deeper water masses.

  9. Flash CS3 The Missing Manual

    CERN Document Server

    Grover, Chris

    2008-01-01

    Flash CS3, the latest version of the premier tool for creating web animations and interactive web sites, can be intimidating to learn. This entertaining reference tutorial provides a reader-friendly animation primer and a guided tour of all the program's tools and capabilities. Beginners will learn to use the software in no time, and experienced users will quickly take their skills to the next level.

  10. On Gács' quantum algorithmic entropy

    Directory of Open Access Journals (Sweden)

    Toru Takisaka

    2014-12-01

    Full Text Available We define an infinite dimensional modification of lower-semicomputability of density operators by Gács with an attempt to fix some problem in the paper. Our attempt is partly achieved by showing the existence of universal operator under some additional assumption. It is left as a future task to eliminate this assumption. We also see some properties and examples which stimulate further research. In particular, we show that universal operator has certain nontrivial form if it exists.

  11. Synthesis, thermal decomposition and sensitivity study of CsDNBF

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shaozong; Zhang, Tonglai; Yang, Li; Zhang, Jianguo; Sun, Yuanhua [State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081 (China)

    2007-02-15

    CsDNBF (cesium 7-hydroxy-4,6-dinitro-5,7-dihydrobenzofuroxanide) was synthesized from the sodium salt of DNBF and cesium nitrate. The thermal decomposition process has been investigated and the results show that the solid residues at 240 C are RCOOCs, CsNCO, RNO{sub 2} and CsNO{sub 3}. The sensitivity results demonstrate that CsDNBF has better properties than KDNBF, which has been widely used. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  12. Quantitative Model for Estimating Soil Erosion Rates Using 137Cs

    Institute of Scientific and Technical Information of China (English)

    YANGHAO; GHANGQING; 等

    1998-01-01

    A quantitative model was developed to relate the amount of 137Cs loss from the soil profile to the rate of soil erosion,According th mass balance model,the depth distribution pattern of 137Cs in the soil profile ,the radioactive decay of 137Cs,sampling year and the difference of 137Cs fallout amount among years were taken into consideration.By introducing typical depth distribution functions of 137Cs into the model ,detailed equations for the model were got for different soil,The model shows that the rate of soil erosion is mainly controlled by the depth distrbution pattern of 137Cs ,the year of sampling,and the percentage reduction in total 137Cs,The relationship between the rate of soil loss and 137Cs depletion i neither linear nor logarithmic,The depth distribution pattern of 137Cs is a major factor for estimating the rate of soil loss,Soil erosion rate is directly related with the fraction of 137Cs content near the soil surface. The influences of the radioactive decay of 137Cs,sampling year and 137Cs input fraction are not large compared with others.

  13. Cesium Platinide Hydride 4Cs 2 Pt-CsH: An Intermetallic Double Salt Featuring Metal Anions

    Energy Technology Data Exchange (ETDEWEB)

    Smetana, Volodymyr [Ames Laboratory, US Department of Energy, and Critical Materials Institute, Ames Iowa 50011-3020 USA; Mudring, Anja-Verena [Ames Laboratory, US Department of Energy, and Critical Materials Institute, Ames Iowa 50011-3020 USA; Department of Materials Sciences and Engineering, Iowa State University, Ames Iowa 50011-3111 USA

    2016-10-24

    With Cs9Pt4H a new representative of ionic compounds featuring metal anions can be added to this rare-membered family. Cs9Pt4H exhibits a complex crystal structure containing Cs+ cations, Pt2- and H- anions. Being a red, transparent compound its band gap is in the visible range of the electromagnetic spectrum and the ionic type of bonding is confirmed by quantum chemical calculations. This cesium platinide hydride can formally be considered as a double salt of the “alloy” cesium–platinum, or better cesium platinide, Cs2Pt, and the salt cesium hydride CsH according to Cs9Pt4H≡4 Cs2Pt∙CsH.

  14. Cesium Platinide Hydride 4Cs2 Pt⋅CsH: An Intermetallic Double Salt Featuring Metal Anions.

    Science.gov (United States)

    Smetana, Volodymyr; Mudring, Anja-Verena

    2016-11-14

    With Cs9 Pt4 H a new representative of ionic compounds featuring metal anions can be added to this rare-membered family. Cs9 Pt4 H exhibits a complex crystal structure containing Cs(+) cations, Pt(2-) and H(-) anions. Being a red, transparent compound its band gap is in the visible range of the electromagnetic spectrum and the ionic type of bonding is confirmed by quantum chemical calculations. This cesium platinide hydride can formally be considered as a double salt of the "alloy" cesium-platinum, or better cesium platinide, Cs2 Pt, and the salt cesium hydride CsH according to Cs9 Pt4 H≡4 Cs2 Pt⋅CsH.

  15. Cesium platinide hydride 4Cs{sub 2}Pt.CsH: an intermetallic double salt featuring metal anions

    Energy Technology Data Exchange (ETDEWEB)

    Smetana, Volodymyr [Ames Laboratory, US Department of Energy, and Critical Materials Institute, Ames, Iowa, 50011-3020 (United States); Mudring, Anja-Verena [Ames Laboratory, US Department of Energy, and Critical Materials Institute, Ames, Iowa, 50011-3020 (United States); Department of Materials Sciences and Engineering, Iowa State University, Ames, Iowa, 50011-3111 (United States)

    2016-11-14

    With Cs{sub 9}Pt{sub 4}H a new representative of ionic compounds featuring metal anions can be added to this rare-membered family. Cs{sub 9}Pt{sub 4}H exhibits a complex crystal structure containing Cs{sup +} cations, Pt{sup 2-} and H{sup -} anions. Being a red, transparent compound its band gap is in the visible range of the electromagnetic spectrum and the ionic type of bonding is confirmed by quantum chemical calculations. This cesium platinide hydride can formally be considered as a double salt of the ''alloy'' cesium-platinum, or better cesium platinide, Cs{sub 2}Pt, and the salt cesium hydride CsH according to Cs{sub 9}Pt{sub 4}H≡4 Cs{sub 2}Pt.CsH. (copyright 2016 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. The "RA" Expeditions: The Archaeological and Anthropological Background. The "RA" Expeditions: The Coriolis Effect. The "RA" Expeditions: The Papyrus Reed. Learning Experiences for Coastal and Oceanic Awareness Studies, Nos. 211, 212, 213. [Project COAST].

    Science.gov (United States)

    Delaware Univ., Newark. Coll. of Education.

    Included are three units related to coastal and oceanic awareness. These are: (1) The "RA" Expeditions: The Archaeological and Anthropological Background; (2) The "RA" Expeditions: The Coriolis Effect; and (3) The "RA" Expeditions: The Papyrus Reed. Each of the three units are designed for students in grades 6-12. Each unit contains teacher…

  17. The "RA" Expeditions: The Archaeological and Anthropological Background. The "RA" Expeditions: The Coriolis Effect. The "RA" Expeditions: The Papyrus Reed. Learning Experiences for Coastal and Oceanic Awareness Studies, Nos. 211, 212, 213. [Project COAST].

    Science.gov (United States)

    Delaware Univ., Newark. Coll. of Education.

    Included are three units related to coastal and oceanic awareness. These are: (1) The "RA" Expeditions: The Archaeological and Anthropological Background; (2) The "RA" Expeditions: The Coriolis Effect; and (3) The "RA" Expeditions: The Papyrus Reed. Each of the three units are designed for students in grades 6-12.…

  18. 54. konferencija za elektroniku, telekomunikacije, računarstvo, automatiku i nuklearnu tehniku ETRAN 2010

    Directory of Open Access Journals (Sweden)

    Nebojša N. Gaćeša

    2010-10-01

    Full Text Available U Donjem Milanovcu je od 7. do 11. juna 2010. godine održana 54. konferencija ETRAN 2010, pod pokroviteljstvom Ministarstva nauke Republike Srbije, u organizaciji Društva za ETRAN i Instituta IMTEL. ETRAN je stručno društvo za elektroniku, telekomunikacije, računarstvo, automatiku i nuklearnu tehniku. To je dobrovoljna, vanstranačka, nevladina, neprofitna i društvena organizacija stručnjaka koji rade u oblasti elektrotehnike i drugim oblastima u kojima se koriste metode i tehnike iz područja delatnosti elektrotehnike. Predsednik predsedništva društva za ETRAN je prof. dr Srđan Stanković sa Elektrotehničkog fakulteta u Beogradu, potpredsednik je prof. dr Bratislav Milovanović sa Elektronskog fakulteta u Nišu, a sekretar je prof. dr Dušan Petrovački sa Fakulteta tehničkih nauka u Novom Sadu. Konferencija ETRAN je najstarija i najuglednija naučno-stručna konferencija u zemlji, sa preko pola veka tradicije i desetinama hiljada publikovanih radova. ETRAN ima uspostavljeno partnerstvo s najvećom i najjačom stručnom organizacijom elektroinženjera na svetu, udruženjem IEEE. Delatnost ETRAN-a odvija se u okviru sledećih stručnih sekcija: Elektronika, Telekomunikacije, Računarstvo, Automatika, Nuklearna tehnika, Akustika, Antene i prostiranje, Bio-medicinska tehnika, Veštačka inteligencija, Elektroenergetika, Električna kola, električni sistemi i obrada signala, Metrologija, Mikroelektronika i optoelektonika, Mikrotalasna i submilimetarska tehnika, Novi materijali i Robotika i fleksibilna automatizacija. Ove godine je za izlaganje na konferenciji, u okviru ovih 16 stručnih sekcija, prihvaćeno 315 radova.

  19. VizieR Online Data Catalog: Redshifts of 5 EDisCS galaxy clusters (Halliday+, 2004)

    Science.gov (United States)

    Halliday, C.; Milvang-Jensen, B.; Poirier, S.; Poggianti, B. M.; Jablonka, P.; Aragon-Salamanca, A.; Saglia, R. P.; de, G. Lucia; Pello, R.; Simard, L.; Clowe, D. I.; Rudnick, G.; Dalcanton, J. J.; White, S. D. M.; Zaritsky, D.

    2004-08-01

    Spectroscopic observations are presented for objects in the fields of 4 galaxy clusters at z=0.7-0.8 (Cl 1040.7-1155 (Cl 1040), Cl 1054.4-1146 (Cl 1054-11), Cl 1054.7-1245 (Cl 1054-12), and Cl 1216.8-1201 (Cl 1216)) and in one cluster at z~0.5 (Cl 1232.5-1250 (Cl 1232)) of the ESO Distant Cluster Survey (EDisCS). We present tables of RA and DE positions for an equinox of 2000 (J2000, epoch 2001), I-band magnitudes for an aperture of radius 1 arcsecond, spectroscopic redshifts for objects in the fields of our 5 clusters, and membership and targeting flags to indicate whether the object is a cluster member and/or was targeted to be a cluster member respectively. (5 data files).

  20. Cone-beam Computed Tomographic Assessment of Canal Centering Ability and Transportation after Preparation with Twisted File and Bio RaCe Instrumentation.

    Directory of Open Access Journals (Sweden)

    Kiamars Honardar

    2014-08-01

    Full Text Available Use of rotary Nickel-Titanium (NiTi instruments for endodontic preparation has introduced a new era in endodontic practice, but this issue has undergone dramatic modifications in order to achieve improved shaping abilities. Cone-beam computed tomography (CBCT has made it possible to accurately evaluate geometrical changes following canal preparation. This study was carried out to compare canal centering ability and transportation of Twisted File and BioRaCe rotary systems by means of cone-beam computed tomography.Thirty root canals from freshly extracted mandibular and maxillary teeth were selected. Teeth were mounted and scanned before and after preparation by CBCT at different apical levels. Specimens were divided into 2 groups of 15. In the first group Twisted File and in the second, BioRaCe was used for canal preparation. Canal transportation and centering ability after preparation were assessed by NNT Viewer and Photoshop CS4 software. Statistical analysis was performed using t-test and two-way ANOVA.All samples showed deviations from the original axes of the canals. No significant differences were detected between the two rotary NiTi instruments for canal centering ability in all sections. Regarding canal transportation however, a significant difference was seen in the BioRaCe group at 7.5mm from the apex.Under the conditions of this in vitro study, Twisted File and BioRaCe rotary NiTi files retained original canal geometry.

  1. Effect of experimental variables onto Co(2+) and Sr(2+) sorption behavior in red mud-water suspensions.

    Science.gov (United States)

    Milenković, Aleksandra S; Smičiklas, Ivana D; Šljivić-Ivanović, Marija Z; Živković, Ljiljana S; Vukelić, Nikola S

    2016-07-02

    The prospects of rinsed red mud (alumina production residue) utilization for liquid radioactive waste treatment have been investigated, with Co(2+) and Sr(2+) as model cations of radioactive elements. To evaluate the sorption effectiveness and corresponding binding mechanisms, the process was analyzed in batch conditions, by varying experimental conditions (pH, Co(2+) and Sr(2+) concentrations in single solutions and binary mixtures, contact time, and the concentration of competing cations and ligands common in liquid radioactive waste). Comparison of the Co(2+) and Sr(2+) sorption pH edges with the red mud isoelectric point has revealed that Co(2+) removal took place at both positive and negative red mud surface, while Sr(2+) sorption abruptly increased when the surface became negatively charged. The increase of initial cation content and pH resulted in increased equilibrium times and sorption capacity and decreased rate constants. From single metal solutions and various binary mixtures, Co(2+) was sorbed more efficiently and selectively than Sr(2+). While Sr(2+) sorption was reduced by coexisting cations in the order Al(3+) ≥ Ca(2+) >Na(+) ≥Cs(+), removal of Co(2+) was affected by Al(3+) species and complexing agents (EDTA and citrate). Desorption of Co(2+) was negligible in Ca(2+) and Sr(2+) containing media and in solutions with initial pH 4-7. Sr(2+) desorption was generally more pronounced, especially at low pH and in the presence of Co(2+). Collected macroscopic data signify that Co(2+) sorption by red mud minerals occurred via strong chemical bonds, while Sr(2+) was retained mainly by weaker ion-exchange or electrostatic interactions. Results indicate that the rinsed red mud represent an efficient, low-cost sorbent for Co(2+) and Sr(2+) immobilization.

  2. [Update on Current Care Guidelines. Rheumatoid Arthritis (RA)].

    Science.gov (United States)

    2015-01-01

    Patients with signs and symptoms of early rheumatoid arthritis (RA) should be referred to a multidisciplinary rheumatology clinic. The ACR-EULAR criteria help in identification of patients with risk for erosive RA. Treatment should aim at early remission. Start with the combination of methotrexate, hydroxychloroquine, sulfasalazine, and low-dose glucocorticoid is recommended if contraindications exist. Methotrexate has better bioavailability as injection. Glucocorticoids are injected into active joints. Patient education with shared decision is essential. Exercise training is recommended. If treatment target is not achieved by the DMARD combination, a biological drug is added.

  3. Process waste assessment: Color print processing (RA-4)

    Energy Technology Data Exchange (ETDEWEB)

    Catlett, P.

    1994-05-01

    The Kodak RA-4 process is used to develop prints and overhead transparencies from photographic negatives. The assessment was based on usage, effluent discharge, and final disposition of waste generated by the process. Two options explored were bleach-fix regeneration and the conversion to a digital image processing system. The RA-4 process is process is environmentally sound and generates a relatively small amount of waste. The bleach-fix option would provide only a small effluent reduction. The digital imaging conversion option, if fully implemented, could greatly reduce waste generated in the photo lab.

  4. Multimodalinė transporto infrastruktūra turizmo paslaugoje

    OpenAIRE

    Simanavičius, Egidijus

    2013-01-01

    Darbo pavadinimas: Multimodalinė transporto infrastruktūra turizmo paslaugoje. Darbo tikslas: įvertinti multimodalinės transporto infrastruktūros turizmo paslaugoje situaciją. Darbo objektas: multimodalinė transporto infrastruktūra turizmo paslaugoje. Tyrimo uždaviniai: 1. Atskleisti multimodalinės transporto infrastruktūros turizmo paslaugoje esmę; 2. Pristatyti Lietuvos transporto infrastruktūros turizmo paslaugoje situaciją; 3. Ištirti multimodalinę infrastruktūrą geležin...

  5. Plutonium, (137)Cs and uranium isotopes in Mongolian surface soils.

    Science.gov (United States)

    Hirose, K; Kikawada, Y; Igarashi, Y; Fujiwara, H; Jugder, D; Matsumoto, Y; Oi, T; Nomura, M

    2017-01-01

    Plutonium ((238)Pu and (239,240)Pu), (137)Cs and plutonium activity ratios ((238)Pu/(239,240)Pu) as did uranium isotope ratio ((235)U/(238)U) were measured in surface soil samples collected in southeast Mongolia. The (239,240)Pu and (137)Cs concentrations in Mongolian surface soils (surface soils (0.013-0.06) coincided with that of global fallout. The (235)U/(238)U atom ratios in the surface soil show the natural one. There was a good correlation between the (239,240)Pu and (137)Cs concentrations in the surface soils. We introduce the migration depth to have better understanding of migration behaviors of anthropogenic radionuclides in surface soil. We found a difference of the migration behavior between (239,240)Pu and (137)Cs from (137)Cs/(239,240)Pu - (137)Cs plots for the Mongolian and Tsukuba surface soils; plutonium in surface soil is migrated easier than (137)Cs.

  6. Bacterial CS2 hydrolases from Acidithiobacillus thiooxidans strains are homologous to the archaeal catenane CS2 hydrolase.

    Science.gov (United States)

    Smeulders, Marjan J; Pol, Arjan; Venselaar, Hanka; Barends, Thomas R M; Hermans, John; Jetten, Mike S M; Op den Camp, Huub J M

    2013-09-01

    Carbon disulfide (CS(2)) and carbonyl sulfide (COS) are important in the global sulfur cycle, and CS(2) is used as a solvent in the viscose industry. These compounds can be converted by sulfur-oxidizing bacteria, such as Acidithiobacillus thiooxidans species, to carbon dioxide (CO(2)) and hydrogen sulfide (H2S), a property used in industrial biofiltration of CS(2)-polluted airstreams. We report on the mechanism of bacterial CS(2) conversion in the extremely acidophilic A. thiooxidans strains S1p and G8. The bacterial CS(2) hydrolases were highly abundant. They were purified and found to be homologous to the only other described (archaeal) CS(2) hydrolase from Acidianus strain A1-3, which forms a catenane of two interlocked rings. The enzymes cluster in a group of β-carbonic anhydrase (β-CA) homologues that may comprise a subclass of CS(2) hydrolases within the β-CA family. Unlike CAs, the CS(2) hydrolases did not hydrate CO(2) but converted CS(2) and COS with H(2)O to H(2)S and CO(2). The CS(2) hydrolases of A. thiooxidans strains G8, 2Bp, Sts 4-3, and BBW1, like the CS(2) hydrolase of Acidianus strain A1-3, exist as both octamers and hexadecamers in solution. The CS(2) hydrolase of A. thiooxidans strain S1p forms only octamers. Structure models of the A. thiooxidans CS(2) hydrolases based on the structure of Acidianus strain A1-3 CS(2) hydrolase suggest that the A. thiooxidans strain G8 CS(2) hydrolase may also form a catenane. In the A. thiooxidans strain S1p enzyme, two insertions (positions 26 and 27 [PD] and positions 56 to 61 [TPAGGG]) and a nine-amino-acid-longer C-terminal tail may prevent catenane formation.

  7. Cultivo purificado de células de Schwann provenientes de ganglios de la raíz dorsal de Ratón adulto

    Directory of Open Access Journals (Sweden)

    Spinel Clara M.

    2006-06-01

    Full Text Available Las células de Schwann (CS son la glía del sistema nervioso periférico. Se encargan de apoyar la función
    neuronal y ayudan a la conducción del impulso nervioso. Estas células juegan un papel muy importante en el
    crecimiento axonal, no solo durante el desarrollo embrional sino durante los procesos de regeneración nerviosa. Las CS secretan un gran número de factores que promueven la regeneración y esto las ha convertido en blanco para el diseño de prótesis artificiales. Para estos estudios es necesario establecer cultivos enriquecidos de CS los cuales son realizados en general a partir de nervios periféricos, sin embargo, ciertos estudios muestran a los ganglios de la raíz dorsal (GRD como una buena fuente para la obtención de estas células. En este estudio se estableció un protocolo para la obtención de CS a partir de GRD de ratones adultos. Mediante técnicas de descapsulación, disociación enzimática y disociación mecánica fue posible establecer cultivos de CS con una pureza del 98%. Los cultivos fueron realizados sobre plástico sin afectar esto la pureza de los mismos. Este protocolo permitió la obtención de grandes poblaciones de CS (3 x 106 células/animal en tan solo un mes. Estos resultados mejoran las perspectivas del uso de los GRD como fuente para la obtención de este tipo celular.

  8. {sup 226}Ra, {sup 228}Ra and {sup 40}K in scales formed in boilers of industrial installations

    Energy Technology Data Exchange (ETDEWEB)

    Poggi, Claudia M. Braga; Farias, Emerson Emiliano G. de; Hazin, Clovis A., E-mail: hazin@cnen.gov.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear; Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Gazineu, Maria Helena P., E-mail: helena@unicap.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear; Universidade Catolica de Pernambuco (UNICAP), Recife, PE (Brazil). Centro de Ciencias e Tecnologia

    2011-07-01

    Many industrial processes involve the production of steam in boilers, which is sent through pipes to machines and other equipment used in different sectors of the installations. The water commonly used in these processes is groundwater, which generally has high concentrations of calcium and magnesium salts, that can co-precipitate with naturally occurring radioactive elements such as {sup 226}Ra and {sup 228}Ra creating radioactive scales, which are deposited in pipes, thus decreasing the efficiency of steam production. In addition, {sup 40}K that is present in all soils and rocks with a concentration of about 0.012% of natural potassium can also be concentrated in these scales. No data was found in literature relating to radionuclides present in the scales formed on boilers in general. In this context, the purpose of this work was to determine concentrations of {sup 226}Ra, {sup 228}Ra and {sup 40}K, in scales generated inside boilers from different industries in the cities of Caruaru, Paulista and Goiana, Pernambuco. Determination of the radionuclides concentration was performed by gamma spectrometry with an HPGe detector, calculating their specific activities. Activity concentrations of {sup 226}Ra were in the range of < 1.4 (Detection Limit) to 1,328.0 {+-} 23.0 Bq.kg{sup -1} and {sup 228}Ra activity concentrations varied from < 1.8 (Detection Limit) to 265.5 {+-} 8.0 Bq.kg{sup 1}. Activity concentrations of {sup 40}K were in the range of < 14.6 (Detection Limit) to 288.1 {+-} 11.5 Bq.kg{sup -1}. All these activity concentrations were lower than the limits established by the Brazilian Nuclear Energy Commission of for this type of matrix. (author)

  9. Genesis of Sr Isotopes in Groundwater of Hebei Plain

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    To analyze the genesis of Sr isotopes in groundwater of Hebei plain, time-accumulative effect of 87Sr/86Sr ratio was studied. It is shown that 87Sr/86Sr ratio increases with the increasing age and depth of groundwater and has a positive correlation to 4Heexc and a negative correlation to δ18O and δD.The groundwater is divided into three groups to discuss the relation between 87Sr/86Sr ratio and Sr2+ content: ① moderate Sr2+ content and higher 87Sr/86Sr ratio (water Ⅰ); ② lower Sr2+ content and higher 87Sr/86Sr ratio (water Ⅱ); and ③ higher Sr2+ content and lower 87Sr/86Sr ratio (water Ⅲ), that is hot water. On the basis of integrated analysis, it was considered that ① the radiogenic Sr in the Quaternary groundwater (Q4-Q1) originates from weathering of silicate rich in Na and Rb, mainly from plagioclase; ② the radiogenic Sr of hot water in Huanghua port is attributed to carbonate dissolution, with lower 87Sr/86Sr ratio and higher Sr/Na ratio; ③ the recharge area is laterally recharged by the groundwater flowing through igneous and metamorphic rocks, with moderate 87Sr/86Sr ratio. However, the formation mechanism of Sr isotopes in Tertiary groundwater needs further studies.

  10. Formation of ultracold LiCs molecules

    CERN Document Server

    Kraft, S D; Lange, J; Vogel, L; Wester, R; Weidemüller, M; Kraft, Stephan D.; Staanum, Peter; Lange, Joerg; Vogel, Leif; Wester, Roland; Weidemueller, Matthias

    2006-01-01

    We present the first observation of ultracold LiCs molecules. The molecules are formed in a two-species magneto-optical trap and detected by two-photon ionization and time-of-flight mass spectrometry. The production rate coefficient is found to be in the range $10^{-18}\\unit{cm^3s^{-1}}$ to $10^{-16}\\unit{cm^3s^{-1}}$, at least an order of magnitude smaller than for other heteronuclear diatomic molecules directly formed in a magneto-optical trap.

  11. Flash CS5 The Missing Manual

    CERN Document Server

    Grover, Chris

    2010-01-01

    Once you know how to use Flash, you can create everything from simple animations to high-end desktop applications, but it's a complex tool that can be difficult to master on your own-unless you have this Missing Manual. This book will help you learn all you need to know about Flash CS5 to create animations that bring your ideas to life. Learn animation basics. Find everything you need to know to get started with FlashMaster the Flash tools. Learn the animation and effects toolset, with clear explanations and hands-on examplesUse 3D effects. Rotate and put objects in motion in three dimensions

  12. Foundation Flash CS4 for Designers

    CERN Document Server

    Green, Tom

    2008-01-01

    In this book, you'll learn:* How to create effective animations using the new Motion Editor and animation tools * How to use the new 3D features to animate objects in 3D space * Best-practice tips and techniques from some of the top Flash practitioners on the planet * How to create captioned video and full-screen video, and deploy HD video using Flash * Techniques for using the Flash UI components as well as XML documents to create stunning,interactive presentations If you're a Flash designer looking for a solid overview of Flash CS4, this book is for you. Through the use of solid and practica

  13. Dreamweaver CS55 The Missing Manual

    CERN Document Server

    McFarland, David

    2011-01-01

    Dreamweaver is the tool most widely used for designing and managing professional-looking websites, but it's a complex program. That's where Dreamweaver CS5.5: The Missing Manual comes in. With its jargon-free explanations, 13 hands-on tutorials, and savvy advice from Dreamweaver expert Dave McFarland, you'll master this versatile program with ease. Get A to Z guidance. Go from building your first web page to creating interactive, database-driven sites.Build skills as you learn. Apply your knowledge through tutorials and downloadable practice files.Create a state-of-the-art website. Use powerf

  14. Adobe After Effects CS5 Digital Classroom

    CERN Document Server

    Smith , Jerron

    2011-01-01

    This video and full-color book combo has quite an effect for learning After Effects CS5! Adobe After Effects is a leading motion graphics and visual effects program that allows you to create and deliver compelling motion graphics and visual effects. This full-color book-and-video training package gets you quickly up to speed using the capabilities of the newest release of After Effects and deciphers even the most complex After Effects tasks. Sixteen self-paced lessons explain how to edit and apply effects for stellar visual and special effects. The supplementary video lessons included with the

  15. Photoshop CS5 The Missing Manual

    CERN Document Server

    Snider, Lesa

    2010-01-01

    Photoshop CS5 is more amazing than ever, but it can be overwhelming if you're just getting started. This book makes learning Photoshop a breeze by explaining things in a conversational, friendly style -- with no technical jargon. After a thorough introduction to the program, you'll delve deep into Photoshop's secrets with expert tips and practical advice you can use every day. Learn your way around. Get a guided tour of Photoshop's efficient new workspaceUnlock the power. Learn the best ways to use layers, channels, masks, paths, and moreBring images to life. Discover how to effectively retou

  16. Adobe Photoshop CS5 for photographers

    CERN Document Server

    Evening, Martin

    2010-01-01

    With the new edition of this proven bestseller, Photoshop users can master the power of Photoshop CS5 with internationally renowned photographer and Photoshop hall-of-famer Martin Evening by their side.  In this acclaimed reference work, Martin covers everything from the core aspects of working in Photoshop to advanced techniques for professional results. Subjects covered include organizing a digital workflow, improving creativity, output, automating Photoshop, and using Camera RAW. The style of the book is extremely clear, with real examples, diagrams, illustrations, and step-by-step ex

  17. Foundation Flash CS5 for Designers

    CERN Document Server

    Green, T

    2010-01-01

    Flash is one of the most engaging, innovative, and versatile technologies available - allowing the creation of anything from animated banners and simple cartoons to Rich Internet Applications, interactive videos, and dynamic user interfaces for web sites, kiosks, devices, or DVDs. The possibilities are endless, and now it just got better. Flash CS5 boasts a host of new features, including better support for mobile devices, a whole new animation engine enabling full manipulation of tweens and paths, custom easing, improved inverse kinematics, a revamped timeline, built-in 3D, and much more. Thi

  18. Cenozoic seawater Sr/Ca evolution

    Science.gov (United States)

    Sosdian, Sindia M.; Lear, Caroline H.; Tao, Kai; Grossman, Ethan L.; O'Dea, Aaron; Rosenthal, Yair

    2012-10-01

    Records of seawater chemistry help constrain temporal variations in geochemical processes that impact the global carbon cycle and climate through Earth's history. Here we reconstruct Cenozoic seawater Sr/Ca (Sr/Casw) using fossil Conus and turritellid gastropod Sr/Ca. Combined with an oxygen isotope paleotemperature record from the same samples, the gastropod record suggests that Sr/Caswwas slightly higher in the Eocene (˜11.4 ± 3 mmol/mol) than today (˜8.54 mmol/mol) and remained relatively stable from the mid- to late Cenozoic. We compare our gastropod Cenozoic Sr/Casw record with a published turritellid gastropod Sr/Casw record and other published biogenic (benthic foraminifera, fossil fish teeth) and inorganic precipitate (calcite veins) Sr/Caswrecords. Once the uncertainties with our gastropod-derived Sr/Casw are taken into account the Sr/Casw record agrees reasonably well with biogenic Sr/Caswrecords. Assuming a seawater [Ca] history derived from marine evaporite inclusions, all biogenic-based Sr/Casw reconstructions imply decreasing seawater [Sr] through the Cenozoic, whereas the calcite vein Sr/Casw reconstruction implies increasing [Sr] through the Cenozoic. We apply a simple geochemical model to examine the implications of divergence among these seawater [Sr] reconstructions and suggest that the interpretation and uncertainties associated with the gastropod and calcite vein proxies need to be revisited. Used in conjunction with records of carbonate depositional fluxes, our favored seawater Sr/Ca scenarios point to a significant increase in the proportion of aragonite versus calcite deposition in shelf sediments from the Middle Miocene, coincident with the proliferation of coral reefs. We propose that this occurred at least 10 million years after the seawater Mg/Ca threshold was passed, and was instead aided by declining levels of atmospheric carbon dioxide.

  19. 88Sr/86Sr fractionation in inorganic aragonite and in corals

    Science.gov (United States)

    Fruchter, Noa; Eisenhauer, Anton; Dietzel, Martin; Fietzke, Jan; Böhm, Florian; Montagna, Paolo; Stein, Moti; Lazar, Boaz; Rodolfo-Metalpa, Riccardo; Erez, Jonathan

    2016-04-01

    Conflicting results have been reported for the stable Sr isotope fractionation, specifically with respect to the influence of temperature. In an experimental study we have investigated the stable Sr isotope systematics for inorganically precipitated and biogenic (coral) aragonite (natural and laboratory-cultured). Inorganic aragonite precipitation experiments were performed from natural seawater using the CO2 diffusion technique. The experiments were performed at different temperatures and different carbonate ion concentrations. 88Sr/86Sr of the inorganic aragonite precipitated in the experiments are 0.2‰ lighter than seawater, but showed no correlation to the water temperature or to CO32- concentration. Similar observations are made in different coral species (Cladocora caespitosa, Porites sp. and Acropora sp.), with identical fractionation from the bulk solution and no correlation to temperature or CO32- concentration. The lack of 88Sr/86Sr variability in corals at different environmental parameters and the similarity to the 88Sr/86Sr fractionation in inorganic aragonite may indicate a similar Sr incorporation mechanism in corals skeleton and inorganic aragonite, and therefore the previously proposed Rayleigh-based multi element model (Gaetani et al., 2011) cannot explain the process of Sr incorporation in the coral skeletal material. It is proposed that the relatively constant 88Sr/86Sr fractionation in aragonite can be used for paleo reconstruction of seawater 88Sr/86Sr composition. The seawater 88Sr/86Sr ratio reconstruction can be further used in calcite samples to reconstruct paleo precipitation rates.

  20. (135)Cs/(137)Cs isotopic ratio as a new tracer of radiocesium released from the Fukushima nuclear accident.

    Science.gov (United States)

    Zheng, Jian; Tagami, Keiko; Bu, Wenting; Uchida, Shigeo; Watanabe, Yoshito; Kubota, Yoshihisa; Fuma, Shoichi; Ihara, Sadao

    2014-05-20

    Since the Fukushima Daiichi nuclear power plant (FDNPP) accident in 2011, intensive studies of the distribution of released fission products, in particular (134)Cs and (137)Cs, in the environment have been conducted. However, the release sources, that is, the damaged reactors or the spent fuel pools, have not been identified, which resulted in great variation in the estimated amounts of (137)Cs released. Here, we investigated heavily contaminated environmental samples (litter, lichen, and soil) collected from Fukushima forests for the long-lived (135)Cs (half-life of 2 × 10(6) years), which is usually difficult to measure using decay-counting techniques. Using a newly developed triple-quadrupole inductively coupled plasma tandem mass spectrometry method, we analyzed the (135)Cs/(137)Cs isotopic ratio of the FDNPP-released radiocesium in environmental samples. We demonstrated that radiocesium was mainly released from the Unit 2 reactor. Considering the fact that the widely used tracer for the released Fukushima accident-sourced radiocesium in the environment, the (134)Cs/(137)Cs activity ratio, will become unavailable in the near future because of the short half-life of (134)Cs (2.06 years), the (135)Cs/(137)Cs isotopic ratio can be considered as a new tracer for source identification and long-term estimation of the mobility of released radiocesium in the environment.

  1. Possible insect vectors of phytoplasmas affiliated with subgroups 16SrI-B, 16SrI-C, 16SrIII-B and 16SrIII-P in Lithuania

    Science.gov (United States)

    Phytoplasma strains affiliated with groups 16SrI, 16SrIII, 16SrV, and 16SrXII have been found in Lithuania, but still little is known about insects that could transmit them. In this study, four phytoplasma strains belonging to phytoplasma subgroups 16SrI-B, 16SrI-C, 16SrIII-B and 16SrIII-P were id...

  2. Kui ei taha, ära õpi? / Peeter Kreitzberg

    Index Scriptorium Estoniae

    Kreitzberg, Peeter, 1948-2011

    2003-01-01

    Autor leiab, et viimase 10 aasta jooksul levinud arusaam - kui ei taha, ära õpi - on tegelikult väga negatiivsete tagajärgedega seisukoht. Haridus ei ole vaid individuaalne hüve ja selle puudumine individuaalne õnnetus, see on kogu ühiskonna probleem

  3. On RA Abstracts: From Rhetorical Structure to Thematic Organisation

    Science.gov (United States)

    Lores, Rosa

    2004-01-01

    This paper reports an analysis of research article (RA) abstracts from linguistics journals from two related angles: rhetorical organisation and thematic structure. Based on a small scale study it reveals two major types of rhetorical organisation, here called the IMRD type and the CARS type. When thematic analysis, in terms of thematic…

  4. Eesti kasutas ära kõik NATO lennutunnid

    Index Scriptorium Estoniae

    2014-01-01

    Eesti on tänavu ära kasutanud kõik NATO strateegilises õhutranspordiprogrammis (SAC) ette nähtud 35 lennutundi, millega Eesti sai kasutada transpordilennukit Boeing C-17 Globemaster. Lennutunnid kulusid Eesti jalaväeüksuse tagasitoomiseks Afganistanist

  5. Improved limit on the $^{225}$Ra electric dipole moment

    CERN Document Server

    Bishof, Michael; Bailey, Kevin G; Greene, John P; Holt, Roy J; Kalita, Mukut R; Korsch, Wolfgang; Lemke, Nathan D; Lu, Zheng-Tian; Mueller, Peter; O'Connor, Thomas P; Singh, Jaideep T; Dietrich, Matthew R

    2016-01-01

    Background: Octupole-deformed nuclei, such as that of $^{225}$Ra, are expected to amplify observable atomic electric dipole moments (EDMs) that arise from time-reversal and parity-violating interactions in the nuclear medium. In 2015, we reported the first "proof-of-principle" measurement of the $^{225}$Ra atomic EDM. Purpose: This work reports on the first of several experimental upgrades to improve the statistical sensitivity of our $^{225}$Ra EDM measurements by orders of magnitude and evaluates systematic effects that contribute to current and future levels of experimental sensitivity. Method: Laser-cooled and trapped $^{225}$Ra atoms are held between two high voltage electrodes in an ultra high vacuum chamber at the center of a magnetically shielded environment. We observe Larmor precession in a uniform magnetic field using nuclear-spin-dependent laser light scattering and look for a phase shift proportional to the applied electric field, which indicates the existence of an EDM. The main improvement to o...

  6. Improved experimental limit on the EDM of 225Ra

    Science.gov (United States)

    Bishof, Michael; Bailey, Kevin; Dietrich, Matthew R.; Greene, John P.; Holt, Roy J.; Kalita, Mukut R.; Korsch, Wolfgang; Lemke, Nathan D.; Lu, Zheng-Tian; Mueller, Peter; O'Connor, Tom P.; Parker, Richard H.; Rabga, Tenzin; Singh, Jaideep T.

    2015-10-01

    Searches for permanent electric dipole moments (EDMs) in fundamental and composite particles are sensitive probes of beyond-standard-model symmetry violation that could explain the dominance of matter over anti-matter. The 225Ra (t1/2 = 15d, I = 1/2) atom is a particularly attractive system to use for an EDM measurement because its large nuclear octupole deformation, closely spaced ground-state parity doublet, and large atomic mass make 225Ra uniquely sensitive to symmetry-violating interactions in the nuclear medium. We have developed an experiment to measure the EDM of 225Ra and demonstrated the first ``proof-of-principle'' measurement, giving a 95% confidence upper limit of 5E-22 e-cm. After implementing a vacuum upgrade, we have observed nuclear spin coherence after 20 s of free evolution - a factor of ten improvement over our earlier results - and have lowered the 225Ra EDM limit by over an order of magnitude. Upcoming experimental upgrades have the potential to further improve our EDM sensitivity by many orders of magnitude, allowing us to test symmetry violation at an unprecedented level. This work is supported by U.S. DOE, Office of Science, Office of Nuclear Physics, under Contract DE-AC02-06CH11357.

  7. Sr partitioning in the benthic foraminifera

    NARCIS (Netherlands)

    Langer, G.; Sadekov, A.; Thoms, S.; Keul, N.; Nehrke, G.; Mewes, A.; Greaves, M.; Misra, S.; Reichart, G.-J.; de Nooijer, L.J.; Bijma, J.; Elderfield, H.

    2016-01-01

    The shallow water benthic foraminifera Ammonia aomoriensis and Amphistegina lessonii were grown at differentseawater Sr/Ca and the test Sr/Ca ratio was determined by Laser Ablation - Inductively Coupled Plasma - MassSpectrometry. A. aomoriensis test Sr/Ca is positively correlated with seawater

  8. Diapycnal nutrient fluxes across the benthic boundary layers at the continental slopes off Peru and Mauritania based on 224Ra/223Ra-ratios

    Science.gov (United States)

    Reichert, P.; Scholten, J. C.; Eisenhauer, A.; Miquel, J. C.; Gasser, B.; Liebetrau, V.; Sommer, S.; Dengler, M.; Bryant, L. D.

    2014-12-01

    Marine sediments may act as sources and/or sinks of nutrients in oxygen minimum zones (OMZs) where solute fluxes between sediments and the above water column are believed to be an important component for the bioproductivity in the mixed layer. However, solute fluxes between sediments and the water column above are difficult to obtain. We determined the diapycnal nutrient fluxes across the benthic boundary layer at the OMZs off Peru and Mauritania using nutrient concentration profiles and vertical diffusion coefficients derived from 224Ra/223Ra isotope ratios. The radium isotopes 223Ra (half-life: 11.4 days) and 224Ra (half-life: 3.66 days) are produced in sediments by radioactive decay of 227Th and 228Th ,respectively: Diffusion of radium out of the sediments results in gradients of 224Ra/223Ra above the sediments; and these gradients may be used to estimate vertical diffusion coefficients. We determined 224Ra/223Ra along two transects at the continental slopes off Peru (12° S) and off Mauritania (18° N) in water depths between 65m - 1000mand 53m - 1100m, respectively. For the 223Ra/224Ra sampling we used acrylic fibers/cartridges coated with MnO2. The Mn-fibers were attached to benthic landers (moored for ~ 24 hours at the sea floor) and the Mn-cartridges were placed in series on several in-situ filtration pumps (Challenger Oceanic and McLane pumps). 223Ra and 224Ra were measured on-board using a delayed coincidence counting system (RaDeCC). In our presentation we will present the 224Ra/223Ra distribution along these transects investigated and we will compare the diapycnal radium-derived nutrient fluxes with those determined using benthic chambers and microstructure measurements.

  9. Canino mandibular con dos raíces

    Directory of Open Access Journals (Sweden)

    Laura Ricardina Ramírez-Sotelo

    Full Text Available El canino inferior es un diente con raíz larga y ancha que le permite una adecuada implantación en el arco dentario. Es considerado un pilar valioso en muchos tratamientos rehabilitadores. Con la finalidad de mantener este elemento dentario es necesario realizar un correcto diagnóstico, para lo que se tendrá en cuenta el conocimiento de las variaciones anatómicas. El objetivo del artículo es presentar un caso de canino mandibular con dos raíces con sus respectivos canales radiculares .Paciente femenina de 21 años, que acudió a la Clínica de Radiología de la Facultad de Odontología de Piracicaba con indicación de una radiografía panorámica para valorar cirugía de terceros molares. Llamó la atención una configuración inusual de las raíces de los caninos mandibulares. En el examen de tomografía computarizada de haz cónico se observó que el canino mandibular del lado derecho presentaba dos raíces separadas, cada una con sus respectivos canales radiculares. Se concluyó que a pesar de la baja prevalencia de las variaciones anatómicas, estas pueden ocurrir en el número de raíces y canales de los caninos mandibulares, tal como se presenta en este reporte de caso.

  10. Improved limit on the 225Ra electric dipole moment

    Science.gov (United States)

    Bishof, Michael; Parker, Richard H.; Bailey, Kevin G.; Greene, John P.; Holt, Roy J.; Kalita, Mukut R.; Korsch, Wolfgang; Lemke, Nathan D.; Lu, Zheng-Tian; Mueller, Peter; O'Connor, Thomas P.; Singh, Jaideep T.; Dietrich, Matthew R.

    2016-08-01

    Background: Octupole-deformed nuclei, such as that of 225Ra, are expected to amplify observable atomic electric dipole moments (EDMs) that arise from time-reversal and parity-violating interactions in the nuclear medium. In 2015 we reported the first "proof-of-principle" measurement of the 225Ra atomic EDM. Purpose: This work reports on the first of several experimental upgrades to improve the statistical sensitivity of our 225Ra EDM measurements by orders of magnitude and evaluates systematic effects that contribute to current and future levels of experimental sensitivity. Method: Laser-cooled and trapped 225Ra atoms are held between two high-voltage electrodes in an ultrahigh-vacuum chamber at the center of a magnetically-shielded environment. We observe Larmor precession in a uniform magnetic field using nuclear-spin-dependent laser light scattering and look for a phase shift proportional to the applied electric field, which indicates the existence of an EDM. The main improvement to our measurement technique is an order-of-magnitude increase in spin-precession time, which is enabled by an improved vacuum system and a reduction in trap-induced heating. Results: We have measured the 225Ra atomic EDM to be less than 1.4 ×10-23e cm (95 % confidence upper limit), which is a factor of 36 improvement over our previous result. Conclusions: Our evaluation of systematic effects shows that this measurement is completely limited by statistical uncertainty. Combining this measurement technique with planned experimental upgrades, we project a statistical sensitivity at the 1 ×10-28e cm level and a total systematic uncertainty at the 4 ×10-29e cm level.

  11. Transfer factors of natural radionuclides and (137)Cs from soil to plants used in traditional medicine in central Serbia.

    Science.gov (United States)

    Djelic, Gorica; Krstic, Dragana; Stajic, Jelena M; Milenkovic, Biljana; Topuzovic, Marina; Nikezic, Dragoslav; Vucic, Dusica; Zeremski, Tijana; Stankovic, Milan; Kostic, Dragana

    2016-07-01

    Transfer factors of natural radionuclides and (137)Cs from soil to plants used in traditional medicine were determined. The transfer factors (TF) were calculated as Bq kg(-1) of dry plant per Bq kg(-1) of dry soil. Mass activity concentrations of (226)Ra, (232)Th, (40)K and (137)Cs in soil and plant samples were measured with high purity germanium detector (HPGe). The concentrations of As, Co, Cr, Cu, Mn, Ni, Pb and Zn were determined, as well as the cation exchange capacity (CEC) and the content of exchangeable cations (Ca, Mg, K, Na). Wide ranges of values were obtained for all the metals, especially for Cr and Ni. The Absalom model was used for determination of the amount of (137)Cs transferred from soil to plant based on soil characteristics such as pH, exchangeable potassium, humus and clay contents. The estimated transfer factors were in the range from 0.011 to 0.307 with an arithmetic mean of 0.071, median of 0.050, geometric mean of 0.053 and geometric standard deviation (GSD) of 2.08. This value agreed well with that calculated from the measurements of 0.069, geometric mean 0.040 and GSD 3.19. Correlations between radionuclides, metals, physicochemical properties and transfer factors were determined by Spearman correlation coefficient. There was a strong positive correlation between (137)Cs transfer factor and the ratio of transfer factor for K and (137)Cs. Principal Component Analysis (PCA) was performed in order to identify some pattern of data. Copyright © 2016. Published by Elsevier Ltd.

  12. Determination of {sup 226}Ra, {sup 228}Ra, and {sup 210}Pb in mushroom from a naturally high radioactive region

    Energy Technology Data Exchange (ETDEWEB)

    Rosa, Mychelle M.L.; Custodio, Luis Gustavo; Cheberle, Luan T.V.; Taddei, Maria Helena T., E-mail: mychelle@cnen.gov.br, E-mail: lgcustodio@hotmail.com, E-mail: lt.cheberle@bol.com.br, E-mail: mhtaddei@cnen.gov.br [Comissao Nacional de Energia Nuclear (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas; Maihara, Vera A., E-mail: vmaihara@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (CNEN/IPEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Many studies have shown that mushrooms are organisms which efficiently accumulate radionuclides and can be used as indicators of environmental contamination and ecosystem quality. The Pocos de Caldas plateau, in Minas Gerais, is a region that has elevated natural radioactivity due to the presence of radiological anomalies of volcanic origin. Seventy areas of radioactive anomalies have been identified in this region. From the radiological point of view the determination of {sup 226}Ra, {sup 228}Ra, and {sup 210}Pb is relevant because they are decay products of the natural series of {sup 238}U and {sup 232}Th, mainly responsible for natural radioactive exposures of man. The present paper is part of a broader study conducted in the Pocos de Caldas plateau, in which the concentration activities of {sup 226}Ra, {sup 228}Ra, and {sup 210}Pb in mushroom samples were determined. The mushrooms were collected at different points of the plateau under the influence of radioactive anomalies and away from the influence of anomalies. From statistical studies a correlation between the accumulation of radionuclides in mushrooms and anomalies was established and it was possible to confirm the efficiency that the mushrooms present as environmental contamination indicators. (author)

  13. Rapid method for determining Sr-89 and Sr-90 using Cherenkov and proportional counting; Schnellmethode zur Bestimmung von SR-89 und SR-90 durch Cerenkov- und Proportionalzaehlermessungen

    Energy Technology Data Exchange (ETDEWEB)

    Lange, S.; Wende, C.; Schwokowski, R.; Alisch-Mark, M.; Abraham, A.; Heinrich, T. [Staatliche Betriebsgesellschaft fuer Umwelt und Landwirtschaft, Radebeul (Germany)

    2016-07-01

    A rapid method for determining Sr-89 and Sr-90 in water, milk and biological samples has been developed and tested. After sample preparation strontium is separated by extraction chromatography using Sr resin. Eluate is divided and transfered to LSC vial and filter paper by SrCO{sub 3} precipitation. A Hidex 300 SL TDCR liquid scintillation counter and Thermo Fisher low level proportional counter have been used. Chemical yield of Sr-85 tracer is determined by Gamma spectroscopy. Uncertainty budget, decision threshold and detection limit are calculated in accordance with GUM and ISO 11929.

  14. Inventory of {sup 226}Ra, {sup 228}Ra and {sup 210}Pb in marine sediments cores of Southwest Atlantic Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Alice M.R.; Oliveira, Joselene de, E-mail: alice.costa@usp.br, E-mail: jolivei@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Gerencia de Metrologia das Radiacoes. Lab. de Radiometria Ambiental; Figueira, Rubens C.L.; Mahiques, Michel M.; Sousa, Silvia H.M., E-mail: rfigueira@usp.br, E-mail: mahiques@usp.br, E-mail: smsousa@usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto Oceanografico

    2015-07-01

    {sup 210}Pb (22.3 y) is a radioactive isotope successfully applied as tracer of sediment dating of the last 100-150 years. The application of {sup 226}Ra and {sup 228}Ra as paleoceanographic tracers (half-lives of 1,600 y and 5.7 y, respectively) also gives some information of ocean's role in past climate change. In this work, it was analyzed 2 sediment cores collect at Southwest Atlantic Ocean. The sediments samples were freeze-dried and acid digested in microwave. It was carried out a radiochemical separation of {sup 226}Ra, {sup 228}Ra and {sup 210}Pb and performed a gross alpha and gross beta measurement of both precipitates Ba(Ra)SO{sub 4} and PbCrO{sub 4} in a low background gas-flow proportional counter. Activity concentrations of {sup 226}Ra ranged from 45 Bq kg{sup -1} to 70 Bq kg{sup -1} in NAP-62 and from 57 Bq kg{sup -1} to 82 Bq kg{sup -1} in NAP-63 samples. The concentration of {sup 228}Ra varied between 37 Bq kg{sup -1} and 150 Bq kg{sup -1} in NAP-62 and between 23 Bq kg{sup -1} and 111 Bq kg{sup -1} in NAP-63 samples. The concentration of total {sup 210}Pb ranged from 126 Bq kg{sup -1} to 256 Bq kg{sup -1} in NAP-62 and from 63 Bq kg{sup -1} to 945 Bq kg{sup -1} in NAP-63 samples. Results of {sup 210}Pb{sub uns} varied from 68 Bq kg{sup -1} to 192 Bq kg{sup -1} for NAP-62, while varied from <4.9 Bq kg{sup -1} to 870 Bq kg{sup -1} in NAP-63 profile. Increased values of {sup 210}Pb{sub uns} were found on the top of both NAP-62 and NAP- 63 sediment profile. (author)

  15. Radiation exposure of relatives of patients treated with Ra-223 dichloride; Strahlenexposition von Angehoerigen bei Therapie mit Ra-223-Dichlorid

    Energy Technology Data Exchange (ETDEWEB)

    Wanke, C.; Szermerski, B.; Solle, A.; Geworski, L. [Medizinische Hochschule Hannover (Germany). Stabsstelle Strahlenschutz und Abt. Medizinische Physik; Pinkert, J. [Bayer Vital GmbH, Leverkusen (Germany); Kranert, W.T. [Frankfurt Univ. (Germany). Klinik fuer Nuklearmedizin; Andreeff, M. [Universitaetsklinikum ' ' Carl Gustav Carus' ' TU Dresden (Germany). Klinik fuer Nuklearmedizin

    2015-07-01

    Since November 2013, a radiopharmaceutical containing Ra-223 dichloride as active substance is approved in the European Union for patients with castration resistant prostate cancer with symptomatic bone metastases and no known visceral metastases. Ra-223 (T{sub 1/2} = 11.43 d) decays via a chain of 4 alpha and 2 beta decays. This therapy is presently the only application of an alpha emitter in clinical routine therapy. To show that the exposure of relatives and caregivers of patients treated with Ra-223 dichloride in an outpatient setting does not exceed a value of 1 mSv, the multicenter study ''RAPSODY'' was conducted. As Ra-223 and most of its progeny emit alpha particles, the internal exposure had to be evaluated in particular. Within this study, measurements of the radiation emitted from the patient were performed using standard dose-rate meters. Wipe-tests were taken in the patients' homes to identify significant contaminations and evaluated by liquid scintillation counting. Samples of saliva and sweat were taken and measured using gamma spectrometry. Ra-223 disintegrates to the noble gas Rn-219 and was measured in the exhaled breath from the patients using conventional Radon Monitors. Furthermore, a computational fluid dynamics simulation (CFD) was performed to assess the radioactivity in the air, which could be inhaled by persons close to the patient. Conclusions: The potential exposure of relatives and caregivers by external irradiation and incorporation of radioactivity exhaled or excreted by the patient with saliva or sweat is well below 1 mSv. No objections are seen regarding outpatient treatment. This paper summarizes contents of a poster presented at the Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging.

  16. The behaviour of sup 137 Cs in some edible fruits

    Energy Technology Data Exchange (ETDEWEB)

    Monte, L.; Quaggia, S.; Pompei, F.; Fratarcangeli, S. (ENEA, Casaccia (Italy). Centro Ricerche Energia)

    1990-01-01

    The aim of this research was to study the behaviour of {sup 137}Cs in fruit-bearing plants following the Chernobyl accident. Samples of hazel-nuts were collected over a period of three years after the accident. The {sup 137}Cs content of the fruit shows an exponential decrease with time. Evaluation of the {sup 134}Cs/{sup 137}Cs ratios in samples of atmospheric particulates, soils and fruit suggests that foliar translocation is the main pathway for {sup 137}Cs migration to the fruit. In addition, estimates of the effective half-times of {sup 137}Cs in hazel-nuts, walnuts, olives and apples and of the 'translocation factors' for hazel-nuts, walnuts, olives, apples and chestnuts have been made. (author).

  17. Efimov Physics in a 6Li-133Cs Atomic Mixture

    Science.gov (United States)

    Johansen, Jacob; Feng, Lei; Parker, Colin; Chin, Cheng; Wang, Yujun

    2015-05-01

    We investigate Efimov physics based on three-body recombination in an atomic mixture of 6Li and 133Cs in the vicinity of interspecies Feshbach resonances at 843 and 889 G. This allows us to compare the loss spectra near different resonances and test the universality of Efimov states. Theoretically the Efimov spectrum near 889 G is expected to be similar to that near 843 G, except that the first resonance is absent near the former Feshbach resonance. This is due to the difference in the Cs-Cs scattering length near the two resonances: At 843 G it is negative, whereas at 889 G it is positive. Although it is primarily the Li-Cs interactions that lead to Efimov resonances, the Cs-Cs scattering length is expected to influence the spectrum. This work is supported by NSF and Chicago MRSEC.

  18. Measurement of 223Ra and 224Ra via RaDeCC and its application at Liaohe River Estuary%辽河口水体中223Ra、224Ra的RaDeCC法测定及应用

    Institute of Scientific and Technical Information of China (English)

    许博超; 姚庆祯; 江雪艳; 于志刚

    2012-01-01

    介绍了同步延时计数法,并应用其对辽河口水体中的223 Ra和224 Ra进行了测定,结合pH、DO、COD、叶绿素、营养盐等参数对223 Ra和224 Ra的放射性活度及其比值随盐度的变化和影响因素进行了讨论,继而以“镭同位素表观年龄模型”计算了辽河口水体的停留时间.结果表明:2010年4月,辽河口调查水域水体中的224 Ra、223 Ra随盐度变化趋势不保守,在盐度为10和26的海域出现了放射性活度高峰值,可能分别由悬浮颗粒物解吸和滨岸咸化的地下水排放等因素造成.水体停留时间随着离开河口距离的增大而增大,最大值出现在盐度为14的海域,达到8.34 d.%Radium delayed coincidence countering system has become the state-of-the-art technique for short-lived radium isotopes (223Ra, 224Ra) measurement. In this paper, we described this system, and used it to measure 223Ra, 224Ra activities at the Liaohe River Estuary. Other parameters, like pH, DO, COD, petroleum hydrocarbon, chlorophyll and nutrients, were used to demonstrate the distribution and impact factors of isotopes activity and ratio versus salinity. Furthermore, the "Apparent Radium Age" model was applied to assess the water residence time at this area. Ra and Ra were not conservative with salinity at the studying area in A-pril, 2010. Two peak activities at salinity 10 and 26 were caused by suspended particles desorption and submarine groundwater discharge , respectively. Water residence time increased with the distance. The oldest age was 8. 34 days at the area with salinity of 14.

  19. Exact CS Reconstruction Condition of Undersampled Spectrum-Sparse Signals

    Directory of Open Access Journals (Sweden)

    Ying Luo

    2013-01-01

    Full Text Available Compressive sensing (CS reconstruction of a spectrum-sparse signal from undersampled data is, in fact, an ill-posed problem. In this paper, we mathematically prove that, in certain cases, the exact CS reconstruction of a spectrum-sparse signal from undersampled data is impossible. Then we present the exact CS reconstruction condition of undersampled spectrum-sparse signals, which is valuable for digital signal compression.

  20. Thermionic work function of /Cs/ZnO

    Science.gov (United States)

    Sommer, A. H.; Briere, T. R.

    1976-01-01

    The collector electrode of a thermionic converter requires a material having a low thermionic work function and chemical stability in a Cs atmosphere in the 800-K range. This letter reports that ZnO with an adsorbed Cs film meets these requirements. The work function is approximately 1.3 eV. Various methods of preparing the ZnO film are described as well as an experiment in which Cs was replaced by K.

  1. The state of Cs-137 in natural water solution

    Energy Technology Data Exchange (ETDEWEB)

    Toropova, V.V.; Toropov, I.G.; Davydov, Yu.P. [Institute of Radioecological, Minsk (Belarus); Efremenkov, V.M. [Institute of Power Engineering, Minsk (Belarus)

    1996-12-31

    The state of Cs radionuclides has been studied in natural water systems - waters of some rivers, water channel, marshes. Investigations were performed using methods of ultrafiltration, dialysis, ion exchange. Based on experimental results obtained conclusions were made on state of radiocaesium in natural waters. It was shown, that Cs in such solutions presents mainly in ionic form. It is shown, how Cs may change its dispersion conditions in natural waters.

  2. A novel yellow-emitting SrAlSi4N7:Ce3+ phosphor for solid state lighting: Synthesis, electronic structure and photoluminescence properties

    Science.gov (United States)

    Ruan, Jian; Xie, Rong-Jun; Funahashi, Shiro; Tanaka, Yoshinori; Takeda, Takashi; Suehiro, Takayuki; Hirosaki, Naoto; Li, Yuan-Qiang

    2013-12-01

    Ce3+-doped and Ce3+/Li+-codoped SrAlSi4N7 phosphors were synthesized by gas pressure sintering of powder mixtures of Sr3N2, AlN, α-Si3N4, CeN and Li3N. The phase purity, electronic crystal structure, photoluminescence properties of SrAlSi4N7:Ce3+(Ce3+/Li+) were investigated in this work. The band structure calculated by the DMol3 code shows that SrAlSi4N7 has a direct band gap of 3.87 eV. The single crystal analysis of Ce3+-doped SrAlSi4N7 indicates a disordered Si/Al distribution and nitrogen vacnacy defects. SrAlSi4N7 was identified as a major phase of the fired powders, and Sr5Al5Si21N35O2 and AlN as minor phases. Both Ce3+ and Ce3+/Li+ doped SrAlSi4N7 phosphors can be efficiently excited by near-UV or blue light and show a broadband yellow emission peaking around 565 nm. A highest external quantum efficiency of 38.3% under the 450 nm excitation was observed for the Ce3+/Li+-doped SrAlSi4N7 (5 mol%). A white light LED lamp with color temperature of 6300 K and color rendering index of Ra=78 was achieved by combining Sr0.97Al1.03Si3.997N\\94\\maccounttest14=t0005_18193 7:Ce3+0.03 with a commercial blue InGaN chip. It indicates that SrAlSi4N7:Ce3+ is a promising yellow emitting down-conversion phosphor for white LEDs.

  3. Preparation and Photocatalytic Properties of Sr2−xBaxTa3O10−yNz Nanosheets

    Directory of Open Access Journals (Sweden)

    Tatsumi Ishihara

    2013-01-01

    Full Text Available Sr2−xBaxTa3O10−yNz (x = 0.0, 0.5, 1.0 nanosheets were prepared by exfoliating layered perovskite compounds (CsSr2−xBaxTa3O10−yNz. The Sr1.5Ba0.5Ta3O9.7N0.2 nanosheet showed the highest photocatalytic activity for H2 production from the water/methanol system among the Sr2−xBaxTa3O9.7N0.2 nanosheets prepared. In addition, Rh-loaded Sr1.5Ba0.5Ta3O9.6N0.3 nanosheet showed the photocatalytic activity for oxygen and hydrogen production from water. The ratio of hydrogen to oxygen evolved was around two. These results indicate that the Rh-loaded Sr1.5Ba0.5Ta3O9.6N0.3 nanosheet is a potential catalyst for photocatalytic water splitting.

  4. CS-Studio Scan System Parallelization

    Energy Technology Data Exchange (ETDEWEB)

    Kasemir, Kay [ORNL; Pearson, Matthew R [ORNL

    2015-01-01

    For several years, the Control System Studio (CS-Studio) Scan System has successfully automated the operation of beam lines at the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor (HFIR) and Spallation Neutron Source (SNS). As it is applied to additional beam lines, we need to support simultaneous adjustments of temperatures or motor positions. While this can be implemented via virtual motors or similar logic inside the Experimental Physics and Industrial Control System (EPICS) Input/Output Controllers (IOCs), doing so requires a priori knowledge of experimenters requirements. By adding support for the parallel control of multiple process variables (PVs) to the Scan System, we can better support ad hoc automation of experiments that benefit from such simultaneous PV adjustments.

  5. Image Fusion Using Pca in Cs Domain

    Directory of Open Access Journals (Sweden)

    M. T. Sadeghi

    2012-09-01

    Full Text Available Compressive sampling (CS, also called Compressed Sensing, has generated a tremendous amount of excitement in the image processing community. It provides an alternative to Shannon/Nyquist sampling when the signal under acquisition is known to be sparse or compressible. In this paper, we propose a new efficient image fusion method for compressed sensing imaging. In this method, we calculate the twodimensional discrete cosine transform of multiple input images, these achieved measurements are multiplied with sampling filter, so compressed images are obtained. we take inverse discrete cosine transform of them. Finally, fused image achieves from these results by using PCA fusion method. This approach also is implemented for multi-focus and noisy images. Simulation results show that our methodprovides promising fusion performance in both visual comparison and comparison using objective measures. Moreover, because this method does not need to recovery process the computational time is decreased very much.

  6. Thermal ionization of Cs Rydberg states

    Science.gov (United States)

    Glukhov, I. L.; Ovsiannikov, V. D.

    2009-01-01

    Rates Pnl of photoionization from Rydberg ns-, np-, nd-states of a valence electron in Cs, induced by black-body radiation, were calculated on the basis of the modified Fues model potential method. The numerical data were approximated with a three-term expression which reproduces in a simple analytical form the dependence of Pnl on the ambient temperature T and on the principal quantum number n. The comparison between approximate and exactly calculated values of the thermal ionization rate demonstrates the applicability of the proposed approximation for highly excited states with n from 20 to 100 in a wide temperature range of T from 100 to 10,000 K. We present coefficients of this approximation for the s-, p- and d-series of Rydberg states.

  7. Vertical distributions of COS and CS2 in Beijing City

    Institute of Scientific and Technical Information of China (English)

    MU Yu-jing; WU Hai; WU Peng-zhang; WANG Yue-si

    2004-01-01

    Vertical distributions of COS and CS2 were measured at a meteorological tower in Beijing City. The mixingratios of COS and CS2 are in the range of 371-1681 pptv and 246-1222 pptv, respectively. The significant highmixing ratios of the two compounds at ground level and distinct vertical distributions indicated the existence of stronganthropogenic sources of COS and CS2 in Beijing City. Domestic stoves and central heaters are important sources ofCOS during winter season. Cesspools may play significant role on COS over whole seasons. Chemical productionsmay be responsible for the observed high mixing ratios of CS2 in Beijing City.

  8. /sup 87/Sr//sup 86/Sr ratios for basalt from Loihi Seamount, Hawaii

    Energy Technology Data Exchange (ETDEWEB)

    Lanphere, M. (Geological Survey, Menlo Park, CA (USA))

    1983-12-01

    /sup 87/Sr//sup 86/Sr ratios of 15 samples of basalt dredged from Loihi Seamount range from 0.70334 to 0.70368. The basalt types range from tholeiite to basanite in composition and can be divided into six groups on the basis of abundances of K/sub 2/O, Na/sub 2/O, Rb and Sr and /sup 87/Sr//sup 86/Sr ratio. The isotopic data require that the various basalt types be derived from source regions differing in Sr isotopic composition. The Loihi basalts may be produced by mixing of isotopically distinct sources, but the tholeiites and alkalic basalts from Loihi do not show a well-developed inverse trend between Rb/Sr and /sup 87/Sr//sup 86/Sr that is characteristic of the later stages of Hawaiian volcanoes such as Haleakala and Koolau.

  9. Microhydration of caesium compounds: Cs, CsOH, CsI and Cs₂I₂ complexes with one to three H₂O molecules of nuclear safety interest.

    Science.gov (United States)

    Sudolská, Mária; Cantrel, Laurent; Cernušák, Ivan

    2014-04-01

    Structure and thermodynamic properties (standard enthalpies of formation and Gibbs free energies) of hydrated caesium species of nuclear safety interest, Cs, CsOH, CsI and its dimer Cs₂I₂, with one up to three water molecules, are calculated to assess their possible existence in severe accident occurring to a pressurized water reactor. The calculations were performed using the coupled cluster theory including single, double and non-iterative triple substitutions (CCSD(T)) in conjunction with the basis sets (ANO-RCC) developed for scalar relativistic calculations. The second-order spin-free Douglas-Kroll-Hess Hamiltonian was used to account for the scalar relativistic effects. Thermodynamic properties obtained by these correlated ab initio calculations (entropies and thermal capacities at constant pressure as a function of temperature) are used in nuclear accident simulations using ASTEC/SOPHAEROS software. Interaction energies, standard enthalpies and Gibbs free energies of successive water molecules addition determine the ordering of the complexes. CsOH forms the most hydrated stable complexes followed by CsI, Cs₂I₂, and Cs. CsOH still exists in steam atmosphere even at quite high temperature, up to around 1100 K.

  10. Origins of invasive piscivores determined from the strontium isotope ratio (87Sr/86Sr) of otoliths

    Science.gov (United States)

    Wolff, Brian A.; Johnson, Brett M.; Breton, Andre R.; Martinez, Patrick J.; Winkelman, Dana L.; Gillanders, Bronwyn

    2012-01-01

    We examined strontium isotope ratios (87Sr/86Sr) in fish otoliths to determine the origins of invasive piscivores in the Upper Colorado River Basin (UCRB, western USA). We examined 87Sr/86Sr from fishes in different reservoirs, as well as the temporal stability and interspecies variability of 87Sr/86Sr of fishes within reservoirs, determined if 87Sr/86Sr would be useful for "fingerprinting" reservoirs where invasive piscivores may have been escaping into riverine habitat of endangered fishes in the UCRB, and looked for evidence that such movement was occurring. Our results showed that in most cases 87Sr/86Sr was unique among reservoirs, overlapped among species in a given reservoir, and was temporally stable across years. We identified the likely reservoir of origin of river-caught fish in some cases, and we were also able to determine the year of possible escapement. The approach allowed us to precisely describe the 87Sr/86Sr fingerprint of reservoir fishes, trace likely origins of immigrant river fish, and exclude potential sources, enabling managers to focus control efforts more efficiently. Our results demonstrate the potential utility of 87Sr/86Sr as a site-specific and temporally stable marker for reservoir fish and its promise for tracking fish movements of invasive fishes in river-reservoir systems.

  11. Reproducing {sup 137}Cs vertical migration in Spanish soils - Reproducing {sup 137}Cs and {sup 90}Sr vertical migration in Spanish mainland

    Energy Technology Data Exchange (ETDEWEB)

    Olondo, C.; Legarda, F.; Herranz, M.; Idoeta, R. [The University of the Basque Country - UPV/EHU, Nuclear Engineering and Fluid Mechanics Dept. Faculty of Engineering, Alda. Urquijo 48013, Bilbao (Spain)

    2014-07-01

    As a result of caesium's and strontium's activity migration study developed in Spanish mainland soils, there has been obtained convective - diffusive migration equation that will reproduce adequately the movement that an activity deposit would follow in this land. Taking into account the dependence on rain that apparent convection velocity shows, it has been defined a new migration parameter that depends only on soil's properties. By means of a least square method and fitting the migration equation to experimental activity profiles, the values showed by the migration parameters in the studied soils, characteristics of that area, have been obtained. After that, there have been obtained the mean values of these parameters for each defined group that, depending on soil's texture, have been observed in the study performed about the movement of both radionuclides in soils and to whom these soils belong. Using these mean values and obtained equation, it has been properly reproduce those vertical activity profiles that were experimentally determined. In order to validate these values, a new sampling programme is carrying out in the north of Spain and, with obtained new sampling points' information, is going to verify if, indeed, obtained mean values also reproduce these new sampling points' activity vertical profile. (authors)

  12. Most přes Račí potok

    OpenAIRE

    Novotný, Matěj

    2014-01-01

    Bakalářská práce řeší most na komunikaci I/60 přes Račí potok. Konstrukce je navrhovaná ve třech variantách. Vybraná byla předpjatá desková konstrukce délky 18,2 metrů uvažovaná jako prostý nosník. Výpočet zatížení je proveden programem SCIA. Konstrukce je posuzována podle platných norem. The Bachelor thesis deals with the road bridge on tfe road I/60 across the "Račí" brook. Construction is proposed in three variants. The selected design was prestressed board length18,2 meters, intended a...

  13. Nuclear structure of 216Ra at high spin

    Indian Academy of Sciences (India)

    S Muralithar; G Rodrigues; R P Singh; R K Bhowmik; P Mukherjee; B Sethi; I Mukherjee

    2012-09-01

    High-spin states of 216Ra ( = 88, = 128) have been investigated through 209Bi(10B, 3n) reaction at an incident beam energy of 55 MeV and 209Bi(11B, 4n) reaction at incident beam energies ranging from 65 to 78 MeV. Based on coincidence data, the level scheme for 216Ra has been considerably extended up to $∼ 33\\hbar$ spin and 7.2 MeV excitation energy in the present experiment with placement of 28 new -transitions over what has been reported earlier. Tentative spin-parity assignments are done for the newly proposed levels on the basis of the DCO ratios corresponding to strong gates. Empirical shell model calculations were carried out to provide an understanding of the underlying nuclear structure.

  14. Enrichment of Vitamin D response elements in RA associated loci supports a role for vitamin D in the pathogenesis of RA

    Science.gov (United States)

    Yarwood, Annie; Martin, Paul; Bowes, John; Lunt, Mark; Worthington, Jane; Barton, Anne; Eyre, Steve

    2013-01-01

    The aim of this study was to explore the role of vitamin-D in rheumatoid arthritis (RA) pathogenesis by investigating enrichment of vitamin-D response elements (VDREs) in confirmed RA susceptibility loci and testing variants associated with vitamin-D levels for association with RA. Bioinformatically, VDRE genomic positions were overlaid with non HLA confirmed RA susceptibility regions. The number of VDREs at RA loci was compared to a randomly selected set of genomic loci to calculate an average relative risk (RR). SNPs in the DHCR7/NADSYN1 and CYP2R1 loci, previously associated with circulating vitamin-D levels, were tested in UK RA cases (n = 3870) and controls (n = 8430). Significant enrichment of VDREs was seen at RA loci (p=9.23×10−8) when regions were defined either by gene (RR 5.50) or position (RR 5.86). SNPs in the DHCR7/NADSYN1 locus showed evidence of positive association with RA, rs4944076 (p=0.008, OR 1.14 95% CI 1.03-1.24). The significant enrichment of VDREs at RA associated loci and the modest association of variants in loci controlling levels of circulating vitamin-D, supports the hypothesis that vitamin-D plays a role in the development of RA. PMID:23636220

  15. Characterization of the CpxRA regulon in Haemophilus ducreyi.

    Science.gov (United States)

    Labandeira-Rey, Maria; Brautigam, Chad A; Hansen, Eric J

    2010-11-01

    The Haemophilus ducreyi 35000HP genome encodes a homolog of the CpxRA two-component cell envelope stress response system originally characterized in Escherichia coli. CpxR, the cytoplasmic response regulator, was shown previously to be involved in repression of the expression of the lspB-lspA2 operon (M. Labandeira-Rey, J. R. Mock, and E. J. Hansen, Infect. Immun. 77:3402-3411, 2009). In the present study, the H. ducreyi CpxR and CpxA proteins were shown to closely resemble those of other well-studied bacterial species. A cpxA deletion mutant and a CpxR-overexpressing strain were used to explore the extent of the CpxRA regulon. DNA microarray and real-time reverse transcriptase (RT) PCR analyses indicated several potential regulatory targets for the H. ducreyi CpxRA two-component regulatory system. Electrophoretic mobility shift assays (EMSAs) were used to prove that H. ducreyi CpxR interacted with the promoter regions of genes encoding both known and putative virulence factors of H. ducreyi, including the lspB-lspA2 operon, the flp operon, and dsrA. Interestingly, the use of EMSAs also indicated that H. ducreyi CpxR did not bind to the promoter regions of several genes predicted to encode factors involved in the cell envelope stress response. Taken together, these data suggest that the CpxRA system in H. ducreyi, in contrast to that in E. coli, may be involved primarily in controlling expression of genes not involved in the cell envelope stress response.

  16. LoRa for the Internet of Things

    OpenAIRE

    Bor, Martin; Vidler, John Edward; Roedig, Utz

    2016-01-01

    New transceiver technologies have emerged which enable power efficient communication over very long distances. Examples of such Low-Power Wide-Area Network (LPWAN)technologies are LoRa, Sigfox and Weightless. A typicalapplication scenario for these technologies is city wide meter reading collection where devices send readings at very low frequency over a long distance to a data concentrator (one-hop networks). We argue that these transceiversare potentially very useful to construct more gener...

  17. Treatment of ankylosing spondylitis with [{sup 224}Ra]-Radiumchloride; Therapie der Spondylitis ankylosans mit [{sup 224}Ra]-Radiumchlorid

    Energy Technology Data Exchange (ETDEWEB)

    Reiners, C. [Klinik und Poliklinik fuer Nuklearmedizin der Univ. Wuerzburg (Germany); Braun, J. [Rheumazentrum Ruhrgebiet Herne (Germany)

    2001-07-01

    Ankylosing spondylitis (AS) is a chronic disease which in 30-50% of the patients leads to considerable episodes of pain, a remarkable reduction of quality of life and disablement. For treatment mostly nonsteroidal antiphlogistic drugs are used which are able to reduce pain in approximately 80% of the patients only. Those drugs however, have to be withdrawn in approximately 30% of the patients due to its known toxicity (mainly in the gastrointestinal tract). Basis medication (DMARDs) is helpful in a minority of AS patients only. Recently [{sup 224}Ra]-Radiumchloride, which has been used previously between 1955 and 1990, has been made available again for treatment of AS. Whereas biokinetics, radiation exposure and the risk-profile of [{sup 224}Ra]-Radiumchloride are documented well by experimental and clinical data, most of the historical studies about the efficacy of this radiopharmaceutical do not fulfill the requirements of modern therapy studies. Therefore as many patients as possible should be recruited for a prospective long-time Phase IV study. A close and well-coordinated cooperation between rheumatologists and nuclear medicine physicians is needed, when [{sup 224}Ra]-Radiumchloride is used for treatment of AS. (orig.) [German] Die meist chronisch, oft auch in Schueben verlaufende Spondylitis ankylosans (AS) fuehrt bei 30-50% der Patienten zu betraechtlichen Schmerzen und einer nicht selten erheblichen Einschraenkung der Lebensqualitaet und Behinderung. Die am haeufigsten zur Therapie verwendeten nichtsteroidalen Antiphlogistika koennen nur bei etwa 80% der Patienten die Schmerzen lindern. Allerdings muessen diese Medikamente bei 20-30% der AS-Patienten wegen ihrer bekannten Toxizitaet - vor allem im Gastrointestinaltrakt - abgesetzt werden. Basistherapeutika (DMARDs) helfen bei der AS nur sehr begrenzt. Mit [{sup 224}Ra]-Radiumchlorid steht seit kurzem ein bereits in den Jahren 1945-1990 fuer die Behandlung der AS verwendetes Radiopharmakon wieder zur

  18. (210)Pb and (137)Cs as tracers of recent sedimentary processes in two water reservoirs in Cuba.

    Science.gov (United States)

    Díaz-Asencio, Misael; Corcho-Alvarado, José Antonio; Cartas-Aguila, Héctor; Pulido-Caraballé, Anabell; Betancourt, Carmen; Smoak, Joseph M; Alvarez-Padilla, Elizabeth; Labaut-Betancourt, Yeny; Alonso-Hernández, Carlos; Seisdedo-Losa, Mabel

    2017-10-01

    Hanabanilla and Paso Bonito Reservoirs are the main fresh water sources for about half a million inhabitants in central Cuba. Prior to this investigation precise information about the losses of storage capacity was not available. Sedimentation is the dominant process leading to reduction in water storage capacity. We investigated the sedimentation process in both reservoirs by analyzing environmental radionuclides (e.g. (210)Pb, (226)Ra and (137)Cs) in sediment cores. In the shallow Paso Bonito Reservoir (mean depth of 6.5 m; water volume of 8 × 10(6) m(3)), we estimated a mean mass accumulation rate (MAR) of 0.4 ± 0.1 g cm(-2)y(-1) based on (210)Pb chronologies. (137)Cs was detected in the sediments, but due to the recent construction of this reservoir (1975), it was not possible to use it to validate the (210)Pb chronologies. The estimated MAR in this reservoir is higher than the typical values reported in similar shallow fresh water reservoirs worldwide. Our results highlight a significant loss of water storage capacity during the past 30 years. In the deeper and larger Hanabanilla Reservoir (mean depth of 15.5 m; water volume of 292 × 10(6) m(3)), the MAR was investigated in three different sites of the reservoir. The mean MARs based on the (210)Pb chronologies varied between 0.15 and 0.24 g cm(-2)y(-1). The MARs calculated based on the (137)Cs profiles further validated these values. We show that the sediment accumulation did not change significantly over the last 50 years. A simple empirical mixing and sedimentation model that assumes (137)Cs in the water originated from both, direct atmospheric fallout and the catchment area, was applied to interpret the (137)Cs depth profiles. The model consistently reproduced the measured (137)Cs profiles in the three cores (R(2) > 0.9). Mean residence times for (137)Cs in the water and in the catchment area of 1 y and 35-50 y, respectively were estimated. The model identified areas where the catchment

  19. Octupole collectivity in $^{220}$Rn and $^{224}$Ra

    CERN Document Server

    Gaffney, Liam Paul

    Collective properties of the radioactive nuclei $^{220}$Rn and $^{224}$Ra have been studied via Coulomb excitation of a 2.8$\\,$A.MeV radioactive ion beam (RIB) incident upon $^{60}$Ni, $^{112,114}$Cd and $^{120}$Sn targets. The experiments took place at the REX-ISOLDE RIB facility, CERN. De-excitation $\\gamma$-ray yields following multiple-step Coulomb excitation were detected in coincidence with recoiling target nuclei in the Miniball spectrometer. For the first time, B(E3;3$^+ \\rightarrow 0^+$) values have been directly measured with a radioactive ion beam. In the process, $^{224}$Ra becomes the heaviest post-accelerated RIB to date at ISOLDE (with the possible exception of the quasi-stable $^{238}$U). The measurements presented in this thesis represent a tripling of the number of nuclei around Z$\\simeq88$ and N$\\simeq134$, for which direct measurements of the octupole collectivity have been performed. The only previous measurements being for the relatively long-lived $^{226}$Ra. The $\\gamma$-ray yields, in...

  20. 223Ra levels fed in the 223Fr β decay

    Science.gov (United States)

    Abdul-Hadi, A.; Barci, V.; Weiss, B.; Maria, H.; Ardisson, G.; Hussonnois, M.; Constantinescu, O.

    1993-01-01

    The 223Fr β decay was reinvestigated using high-resolution single γ spectrometry as well as γ-γ coincidence techniques. For single γ-spectra measurements, radiochemically pure 223Fr sources were obtained by chromatographic separation from a 75 MBq activity 227Ac parent source and continuously purified of 223Ra and daughters. The analysis of the γ spectra of 30 sources showed the existence of 131 γ lines, of which 87 are reported for the first time in the 223Fr β decay although many of them are observed following the 227Th α decay. The 223Fr half-life was remeasured and found to be T1/2=22.00+/-0.07 min. γ-γ-t coincidence measurements were also carried out with 223Fr purified sources. The 223Ra level scheme was built on the basis of our γ data, as well as 227Th α-decay data. Among the 32 excited 223Ra levels, of which 22 were also known from 227Th α decay, 13 are newly reported from 223Fr β decay. Low energy levels (E<400 keV) may be classified as parity doublet bands according to the predictions of the reflection asymmetric rotor model. Above a 700 keV gap, a coexistence of symmetric and asymmetric shapes including both static and dynamic octupole correlations is suggested.

  1. Trapping of short lived Ra{sup +} ions

    Energy Technology Data Exchange (ETDEWEB)

    Bekker, H.; Nunes Portela, M.; Seelen, D.; Dermois, O.; Jungmann, K.; Onderwater, C.J.G.; Timmermans, R.G.E.; Willmann, L.; Wilschut, H.W. [KVI, University of Groningen, NL (Germany)

    2012-07-01

    A precision measurement of atomic parity violation in order to determine electroweak mixing angle at low energy scale is underway at the KVI, University of Groningen. The experiment exploits the large sensitivity of a single trapped Ra{sup +} ion. It requires the trapping of short lived radium ions in a Paul trap. Our first laser spectroscopy on an ensemble of trapped short-lived {sup 209-214}Ra{sup +} isotopes employed buffer gas cooled ions in a linear Paul trap. It provided hyperfine structure of the 6d {sup 2}D{sub 3/2} states and isotope shift of the 6d {sup 2}D{sub 3/2}-7p {sup 2}P{sub 1/2} transition. In a next step the buffer gas cooled Ra ions are extracted from the trap and transported in an electrostatic transport system towards a small Paul trap in an UHV environment. Here the ion can be cooled and subsequently microwave transitions between hyperfine states in the 6d {sup 2}D{sub 3/2} manifold can be driven in order to yield high precision results on the hyperfine constants. These results provide input for the ongoing precision atomic structure calculations.

  2. Raízes e estruturas da sociedade brasileira

    Directory of Open Access Journals (Sweden)

    Leonor Natividade de Campos Medeiros

    2014-05-01

    Full Text Available Este estudo teve como objetivo conhecer e refletir as raízes e estruturas da sociedade brasileira, na visão de dois grandes pensadores: Sérgio Buarque de Holanda com Raízes do Brasil e Gilberto Freyre com Casa-Grande & Senzala. Holanda dividiu o Brasil em duas fases a primeira da colonização portuguesa e a segunda uma critica ao Estado Novo. Freyre mostra a organização social, política e econômica da época da colonização e desenvolve seus estudos ao final da década de 1920, época em que o ambiente intelectual brasileiro está sob a força do modernismo. Conclui-se que o pensamento de Holanda e Freyre se assemelha em alguns aspectos e diverge em outros.   Sociologia de Freyre; Sociologia de Holanda; Raízes da sociedade brasileira

  3. An improved limit on the EDM of 225 Ra

    Science.gov (United States)

    Bishof, Michael; Bailey, Kevin; Dietrich, Matthew R.; Greene, John P.; Holt, Roy J.; Kalita, Mukut R.; Korsch, Wolfgang; Lemke, Nathan D.; Lu, Zheng-Tian; Mueller, Peter; O'Connor, Thomas P.; Parker, Richard H.; Rabga, Tenzin; Singh, Jaideep T.

    2016-05-01

    Searches for permanent electric dipole moments (EDMs) are sensitive probes of symmetry violation that could explain the dominance of matter over anti-matter. The 225 Ra (t1/2 = 15 days, I = 1/2) atom is a particularly attractive system to use for an EDM measurement because its octupole-deformed nucleus, closely spaced ground-state parity doublet, and large nuclear charge make 225 Ra uniquely sensitive to symmetry-violating interactions in the nuclear medium. In 2015, we reported the first ``proof of principle'' measurement of the 225 Ra EDM, giving a 95% confidence upper limit of 5* 10-22 e-cm; representing the first EDM measurement using laser-trapped atoms as well as the first EDM measurement of an atom with an octupole-deformed nucleus. After implementing upgrades to our apparatus, we now observe nuclear spin coherence after 20 s of free evolution - a factor of ten improvement. A new EDM measurement based on the upgraded system improved the 95% confidence upper limit by a factor of 36. We also report on the progress of current experimental upgrades that have the potential to further improve our EDM sensitivity by many orders of magnitude, allowing us to test symmetry violation at an unprecedented level. This work is supported by U.S. DOE, Office of Science, Office of Nuclear Physics, under Contract DE-AC02-06CH11357.

  4. Dispersion and fate of ⁹⁰Sr in the Northwestern Pacific and adjacent seas: global fallout and the Fukushima Dai-ichi accident.

    Science.gov (United States)

    Maderich, V; Jung, K T; Bezhenar, R; de With, G; Qiao, F; Casacuberta, N; Masque, P; Kim, Y H

    2014-10-01

    The 3D compartment model POSEIDON-R was applied to the Northwestern Pacific and adjacent seas to simulate the transport and fate of (90)Sr in the period 1945-2010 and to perform a radiological assessment on the releases of (90)Sr due to the Fukushima Dai-ichi nuclear accident for the period 2011-2040. The contamination due to runoff of (90)Sr from terrestrial surfaces was taken into account using a generic predictive model. A dynamical food-chain model describes the transfer of (90)Sr to phytoplankton, zooplankton, molluscs, crustaceans, piscivorous and non-piscivorous fishes. Results of the simulations were compared with observation data on (90)Sr for the period 1955-2010 and the budget of (90)Sr activity was estimated. It was found that in the East China Sea and Yellow Sea the riverine influx was 1.5% of the ocean influx and it was important only locally. Calculated concentrations of (90)Sr in water, bottom sediment and marine organisms before and after the Fukushima Dai-ichi accident are in good agreement with available experimental measurements. The concentration of (90)Sr in seawater would return to the background levels within one year after leakages were stopped. The model predicts that the concentration of (90)Sr in fish after the Fukushima Dai-ichi accident shall return to the background concentrations only 2 years later due to the delay of the transfer throughout the food web and specific accumulation of (90)Sr. The contribution of (90)Sr to the maximal dose rate due to the FDNPP accident was three orders of magnitude less than that due to (137)Cs, and thus well below the maximum effective dose limits for the public.

  5. Do CS-US pairings actually matter? A within-subject comparison of instructed fear conditioning with and without actual CS-US pairings.

    Directory of Open Access Journals (Sweden)

    An K Raes

    Full Text Available Previous research showed that instructions about CS-US pairings can lead to fear of the CS even when the pairings are never presented. In the present study, we examined whether the experience of CS-US pairings adds to the effect of instructions by comparing instructed conditioning with and without actual CS-US pairings in a within-subject design. Thirty-two participants saw three fractals as CSs (CS(+1, CS(+2, CS(- and received electric shocks as USs. Before the start of a so-called training phase, participants were instructed that both CS(+1 and CS(+2 would be followed by the US, but only CS(+1 was actually paired with the US. The absence of the US after CS(+2 was explained in such a way that participants would not doubt the instructions about the CS(+2-US relation. After the training phase, a test phase was carried out. In this phase, participants expected the US after both CS(+s but none of the CS(+s was actually paired with the US. During test, self-reported fear was initially higher for CS(+1 than for CS(+2, which indicates that the experience of actual CS-US pairings adds to instructions about these pairings. On the other hand, the CS(+s elicited similar skin conductance responses and US expectancies. Theoretical and clinical implications are discussed.

  6. Do CS-US pairings actually matter? A within-subject comparison of instructed fear conditioning with and without actual CS-US pairings.

    Science.gov (United States)

    Raes, An K; De Houwer, Jan; De Schryver, Maarten; Brass, Marcel; Kalisch, Raffael

    2014-01-01

    Previous research showed that instructions about CS-US pairings can lead to fear of the CS even when the pairings are never presented. In the present study, we examined whether the experience of CS-US pairings adds to the effect of instructions by comparing instructed conditioning with and without actual CS-US pairings in a within-subject design. Thirty-two participants saw three fractals as CSs (CS(+)1, CS(+)2, CS(-)) and received electric shocks as USs. Before the start of a so-called training phase, participants were instructed that both CS(+)1 and CS(+)2 would be followed by the US, but only CS(+)1 was actually paired with the US. The absence of the US after CS(+)2 was explained in such a way that participants would not doubt the instructions about the CS(+)2-US relation. After the training phase, a test phase was carried out. In this phase, participants expected the US after both CS(+)s but none of the CS(+)s was actually paired with the US. During test, self-reported fear was initially higher for CS(+)1 than for CS(+)2, which indicates that the experience of actual CS-US pairings adds to instructions about these pairings. On the other hand, the CS(+)s elicited similar skin conductance responses and US expectancies. Theoretical and clinical implications are discussed.

  7. CsEuBr3: Crystal structure and its role in the photostimulation of CsBr :Eu2+

    Science.gov (United States)

    Hesse, S.; Zimmermann, J.; von Seggern, H.; Ehrenberg, H.; Fuess, H.; Fasel, C.; Riedel, R.

    2006-10-01

    CsBr :Eu2+ has recently been investigated as a photostimulable x-ray storage phosphor with great potential for application in high-resolution image plates. In a recent paper Hackenschmied et al. [J. Appl. Phys. 93, 5109 (2003)] suggested that segregations of CsEuBr3 or Cs4EuBr6 formed within CsBr :Eu2+ during annealing are responsible for an increase in the photostimulated luminescence (PSL) yield. In this work single crystals of CsEuBr3 were prepared by a one step synthesis and identified by x-ray diffraction (XRD) analysis as single phase perovskites. It was concluded that, after preparation, CsEuBr3 degrades in normal atmosphere into at least two phases, one of which is the orthorhombic structure of Cs2EuBr5•10H2O. The XRD powder diffraction pattern of this compound is very similar to that of the segregations observed within CsBr :Eu2+ and reported by Hackenschmied et al. However, the increased PSL yield in CsBr :Eu2+ after annealing cannot be due to the segregations, because the trivalent nature of the europium in the segregations renders them PSL inactive.

  8. Zero Patterns of CS-Matrix%关于CS-阵的零位模式

    Institute of Scientific and Technical Information of China (English)

    徐光辉

    2004-01-01

    一个(0,1,-1)-阵A=(aij)的零位模式是指以元素aij的绝对值|aij|为元素所组成的(0,1)矩阵.本文对CS-阵及BCS-阵的零位模式进行了较深入的研究,得到了一些较好的结果.

  9. Caracterização de oito raças do bicho-da-seda (Bombyx mori L. Characterization of eight silkworm races (Bombyx mori L.

    Directory of Open Access Journals (Sweden)

    Antonio José Porto

    2004-02-01

    Full Text Available O experimento foi conduzido na Estação Experimental de Zootecnia de Gália, do Instituto de Zootecnia, SAA-SP, no ano de 2000. Oito raças de bicho-da-seda, de origem Japonesa e Chinesa foram estudadas (B101, B102, B104, B109, C201, C202, C203, C208 em relação a caracteres biológicos (Ganho de peso total de uma lagarta-GP, Porcentagem de mortalidade-MO, Número de machos-NM, Número de fêmeas-NF, Número de ovos/postura-OP e Porcentagem de eclosão-EC e caracteres de produção de casulo (Peso unitário da glândula sericígena-GS, Peso de 30 cascas séricas-CS, Peso de 30 crisálidas-PC, Teor de seda líquido-TS, Casulos desclassificados-CD, Comprimento do casulo-CC e Largura do casulo-LC. O delineamento experimental foi o inteiramente casualizado, com quatro repetições/raça. Não houve variação entre as raças para GP, MO, NF e OP. A raça B101 apresentou, no geral, um menor NM e uma menor EC. Quanto à produção de casulos, no geral, os melhores resultados foram apresentados pela raça C202, com um bom GS (38% do peso final da lagarta, um dos mais altos CS e TS e valores próximos da média para PC, CD, CC e LC. A raça C201, em relação ao casulo produzido, apresentou os piores resultados.The experiment was developed at Estação Experimental de Zootecnia de Galia - Instituto de Zootecnia, SAA-SP, Gália city, São Paulo, Brazil, on 2000. Eight silkworm races of Japanese and Chinese origin were studied (B101, B102, B104, B109, C201, C202, C203, C208 for biological characters ( Total weight-gain for one caterpillar-GP, Percentage of mortality-MO, Number of male-NM, Number of female-NF, Number of egg/laying-OP and Percentage of eclodibility-EC and for characters of cocoon production (silk gland unitary weight-GS, 30 cocoon shell weight-CS, 30 chrysalis weight-PC, silk net purport -TS, disqualified cocoon-CD, cocoon length-CC and cocoon breadth -LC. It was used a completely randomized design, with four replications/ race. It was

  10. Doses from {sup 222}Rn, {sup 226}Ra, and {sup 228}Ra in groundwater from Guarani aquifer, South America

    Energy Technology Data Exchange (ETDEWEB)

    Bonotto, D.M. E-mail: dbonotto@rc.unesp.br

    2004-07-01

    Groundwater samples were analysed for {sup 222}Rn, {sup 226}Ra, and {sup 228}Ra in Guarani aquifer spreading around 1 million km{sup 2} within four countries in South America, and it was found that their activity concentrations are lognormally distributed. Population-weighted average activity concentration for these radionuclides allowed to estimate a value either slightly higher (0.13 mSv/year) than 0.1 mSv for the total effective dose or two times higher (0.21 mSv/year) than this limit, depending on the choice of the dose conversion factor. Such calculation adds useful information for the appropriate management of this transboundary aquifer that is socially and economically very important to about 15 million inhabitants living in Brazil, Argentina, Uruguay and Paraguay.

  11. Possibility of rapidly reporting 226Ra activity in 226Ra-222Rn samples with unknown equilibrium factor by γ spectrometer

    Institute of Scientific and Technical Information of China (English)

    SU Qiong; ZHENG Rui; CHEN Yong; CHENG Jian-Ping

    2004-01-01

    This paper reports the observed changes for equilibrium factors between 226Ra and 222Rn with sealing time of the samples. The samples include soil, raw coal, mineral water, cement, rock, etc. Especially the conceptions of "pre-equilibrium time" and "pre-equilibrium factor" have been put forward and methods of measuring and processing data have been given which can be used for rapidly reporting activity of 226Ra in samples with unknown equilibrium factor. It is definitely concluded that, using methods given in the paper, a test report will be completed in 3~7days, instead of one month, after receiving the sample whose activity is not lower than LLD of the spectrometer.

  12. U-Th-Ra disequilibria at the Masaya (Nicaragua); Desequilibres U-Th-Ra au Masaya (Nicaragua)

    Energy Technology Data Exchange (ETDEWEB)

    Sigmarsson, O.; Condomines, M. [Centre de Recherches Volcanologiques, CNRS URA-10, 63 - Clermont Ferrand (France)

    1996-12-31

    {sup 238}U-{sup 230}Th-{sup 226}Ra radioactive disequilibria were measured in several basalt samples of the post-caldera flows of the Masaya volcano (Nicaragua). {sup 230}Th/{sup 232}Th ratios are from the highest known in the world (about 2.53) with {sup 230}Th/{sup 238}U ratios close to 1. These exceptionally high isotopic thorium ratios from the Masaya and other neighboring volcanoes (Conception, Cerro Negro, Momotombo) are followed by very high {sup 10}Be/{sup 9}Be ratios (60 10{sup -11} for the 1722 flow). These geochemical characteristics with {delta}{sup 18}O of typical mantle origin (5.55) suggest an influence of the subducted sediments fluids in the magma source. The age of the metasomatism ranges from 10 to 0.3 Ma. Initial {sup 226}Ra/{sup 230}Th ratios measured in four historical flows vary from 1.3 to 1.4 and are anti-correlated with the Th content. These variations are probably linked to the fractionated crystallisation of plagioclase minerals. The initial {sup 226}Ra/Ba ratio remains constant and suggests the existence of a huge stationary magmatic reservoir. This hypothesis is also confirmed by the disproportion between the SO{sub 2} quantity emitted by the volcano and by the degassing of lavas on the ground. The {sup 226}Ra excess observed in the Masaya lavas can be the result of a second stage of metasomatism which occurred less than 8000 years B.P. during partial fusion. Abstract only. (J.S.).

  13. An evaluation of ²²⁶Ra and ²²⁸Ra in drinking water in several counties in Texas, USA.

    Science.gov (United States)

    Landsberger, S G; George, G

    2013-11-01

    Naturally Occurring Radioactive Material (NORM) or Technology Enhanced Naturally Occurring Radioactive Material (TENORM) can be a potential health risk. It is now well known that the underlying geology in many parts of Texas has given rise to levels of (226)Ra and (228)Ra that often exceed the limits set by the US Environmental Protection Agency. A detailed literature search was undertaken to assess the levels of (226)Ra and (228)Ra in all of the Texas counties. Several statistical evaluations of the data were performed. The Hickory aquifer in the Llano Uplift region of Texas has consistently had the highest number of (226)Ra and (228)Ra concentrations above the legal limit. As well many of the affected rural communities may not have the financial resources to rectify the problem.

  14. Scintillation properties of CsI:In single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Gridin, S., E-mail: gridin.sergey@gmail.com [Institute for Scintillation Materials, 61001 Kharkov (Ukraine); Institut Lumière Matière, Lyon, 69622 Villeurbanne Cedex (France); Belsky, A. [Institut Lumière Matière, Lyon, 69622 Villeurbanne Cedex (France); Moszynski, M.; Syntfeld-Kazuch, A. [National Centre for Nuclear Research, Soltana 7, 05-400 Otwock-Swierk (Poland); Shiran, N.; Gektin, A. [Institute for Scintillation Materials, 61001 Kharkov (Ukraine)

    2014-10-11

    Scintillation properties of CsI:In single crystals have been investigated. Scintillation yield of CsI:In measured with the 24 μs integration time is around 27,000 ph/MeV, reaching the saturation at 0.005 mol% of the activator. However, luminescence yield of CsI:In is close to CsI:Tl scintillation crystals, which is around 60,000 ph/MeV. This difference is explained by the presence of an ultra-long afterglow in CsI:In scintillation pulse. Thermoluminescence studies revealed a stable trap around 240 K that is supposed to be related to millisecond decay components. The best measured energy resolution of (8.5±0.3)% was achieved at 24 μs peaking time for a CsI sample doped with 0.01 mol% of In. Temperature stability of CsI:In radioluminescence intensity was found to be remarkably high. Its X-ray luminescence yield remains stable up to 600 K, whereafter thermal quenching occurs. The latter property gives CsI:In a potential to be used in well logging applications.

  15. Narrating Data Structures: The Role of Context in CS2

    Science.gov (United States)

    Yarosh, Svetlana; Guzdial, Mark

    2008-01-01

    Learning computing with respect to the context of its use has been linked in previous reports to student motivation in introductory Computer Science (CS) courses. In this report, we consider the role of context in a second course. We present a case study of a CS2 data structures class that uses a media computation context. In this course, students…

  16. Coupling catalytic hydrolysis and oxidation for CS2 removal

    Institute of Scientific and Technical Information of China (English)

    WANG Li; WU Diyong; WANG Shudong; YUAN Quan

    2008-01-01

    CS2 removal was Obtained by coupling catalytic hyidation on bi-functional catalyst.On the hydrolysis active sites,CS2 is hydrolyzed to H2S,while on the oxidation active sites,H2S is oxidized to elemental S or sulfuric acid deposited on the porous support.The above process can be expressed as follows:CS2→H2O COS →H2O H2S→O2 S/SO2- 4.H2S oxidation eliminates its prohibition on CS2 hydrolysis so that the rate of coupling removal CS2 is 5 times higher than that of CS2 hydrolysis.The same active energy of hydrolysis and coupling reaction also indicates that H2S oxidation does not change the reaction mechanism of CS2 hydrolysis.Temperature has obvious effect on the process while the mole ratio of O2 concentration to CS2 concentration (O/S) does not,especially in excess of 2.5.The formation of sulfuric acid on the catalyst surface poisons hydrolysis active sites and causes the decrease of left OH-1 concentration on the catalysts surface.Lower temperature is suggested for this bi-functional catalyst owing to the low yield ratio of S/SO4 2-.

  17. Identification of 137Cs Reference Sites in Southeastern China

    Institute of Scientific and Technical Information of China (English)

    TANG Xiang-Yu; YANG Hao; DU Ming-Yuan; ZHAO Qi-Guo; LI Ren-Ying

    2006-01-01

    The 137Cs vertical distributions in uncultivated and cultivated soils, developed from Quaternary red clay, granite,argillaceous shale, and red sandstone, were studied to develop reliable guidelines for selecting reference sites in southeastern China, which is dominated by strong acidic and/or clay-textured soils, and examine their reliability by comparing them to the reported 137Cs reference inventory data to see whether they agreed with the global distribution pattern. It was observed that a relatively high proportion of 137Cs was concentrated in the surface layers of soils with relatively high clay content. In the paddy soils developed from granite more 137Cs penetrated to depths below the plow layer (about 45.3%),when compared to those from the other three parent materials. The relatively low soil 137Cs inventories on crests excluded using the crest as the 137Cs reference site; instead the paddy field on the hillock plain was selected. Furthermore, within a specific county characterized by great systematic spatial variations of rainfall and topography across the landscape,a significant (P < 0.01) and positive linear relationship (r2 = 0.81) between local 137Cs inventory and corresponding local annual rainfall was observed. Thus, for areas with large variations in rainfall, a single uniform value of local 137Cs reference inventory should be used with caution.

  18. Experience with CsI(Na) crystals for calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Aulchenko, V.M. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Baibusinov, B.O. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Baldin, E.M. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Bondar, A.E. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Gaidarev, P.B. [Cornell Univ., Ithaca, NY (United States); Kuzmin, A.S. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Leontiev, L.A. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Oreshkin, S.B. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Ovechkin, R.P. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Shwartz, B.A. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki

    1996-09-21

    The performance of cesium iodide doped with sodium is studied. The design and parameters of a CsI(Na) endcap calorimeter for the KEDR detector are presented. Also reported are the results of the study of a calorimeter element consisting of a CsI(Na) crystal coupled to a vacuum phototriode. (orig.).

  19. Distribution and behavior of {sup 137}Cs in undisturbed soil

    Energy Technology Data Exchange (ETDEWEB)

    Satta, Naoya [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst.

    1996-04-01

    The depth distribution of {sup 137}Cs in soils which has not been artificially disturbed for 100 years was compared to fallout history. The model of {sup 137}Cs distribution rate was established to estimate fallout history from soil samples. (J.P.N.)

  20. Antibodies derived from an enterotoxigenic Escherichia coli (ETEC) adhesin tip MEFA (multiepitope fusion antigen) against adherence of nine ETEC adhesins: CFA/I, CS1, CS2, CS3, CS4, CS5, CS6, CS21 and EtpA.

    Science.gov (United States)

    Nandre, Rahul M; Ruan, Xiaosai; Duan, Qiangde; Sack, David A; Zhang, Weiping

    2016-06-30

    Diarrhea continues to be a leading cause of death in children younger than 5 years in developing countries. Enterotoxigenic Escherichia coli (ETEC) is a leading bacterial cause of children's diarrhea and travelers' diarrhea. ETEC bacteria initiate diarrheal disease by attaching to host receptors at epithelial cells and colonizing in small intestine. Therefore, preventing ETEC attachment has been considered the first line of defense against ETEC diarrhea. However, developing vaccines effectively against ETEC bacterial attachment encounters challenge because ETEC strains produce over 23 immunologically heterogeneous adhesins. In this study, we applied MEFA (multiepitope fusion antigen) approach to integrate epitopes from adhesin tips or adhesive subunits of CFA/I, CS1, CS2, CS3, CS4, CS5, CS6, CS21 and EtpA adhesins and to construct an adhesin tip MEFA peptide. We then examined immunogenicity of this tip MEFA in mouse immunization, and assessed potential application of this tip MEFA for ETEC vaccine development. Data showed that mice intraperitoneally immunized with this adhesin tip MEFA developed IgG antibody responses to all nine ETEC adhesins. Moreover, ETEC and E. coli bacteria expressing these nine adhesins, after incubation with serum of the immunized mice, exhibited significant reduction in attachment to Caco-2 cells. These results indicated that anti-adhesin antibodies induced by this adhesin tip MEFA blocked adherence of the most important ETEC adhesins, suggesting this multivalent tip MEFA may be useful for developing a broadly protective anti-adhesin vaccine against ETEC diarrhea. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Radiochemical determination and separation or total radium, 226Ra and 224Ra; Analisis Radioquimico de Radio total, Radio-226 y Radio-224

    Energy Technology Data Exchange (ETDEWEB)

    Suarez, J. A.; Gonzalez, J. A.; Pablo, M. A. de

    1987-07-01

    Radiochemical purification and separation of radium has been carried out and the determination of total radium solubilized in aqueous samples has been studied assuming that all the alpha emitters of the sample have their origin in the 226Ra and elements of its desintegration chain. Also, the activities of 22Ra and 226 Ra have been evaluated separately doing a measurement after the chemical separation of the radium and another one 10 days after. (Author) 9 refs.

  2. Determination of Ra natural isotopes in marine samples from Itamaraca coastal regions; Determinacao de isotopos naturais de Ra em amostras costeiras da regiao de Itamaraca (PE)

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, Patricia B.; Valentim, Eliane; Lima, Ricardo A. [Centro Regional de Ciencias Nucleares (CRCN), Recife, PE (Brazil)]. E-mail: pbrandao@cnen.gov.br; Medeiros, Carmem [Pernambuco Univ., Recife, PE (Brazil). Dept. de Oceanografia; Oliveira, Joselene [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    2005-07-01

    Groundwater plays an important role in the transport of nutrients and pollutants to the coastal marine environment s and other surfaces water. Concentrations of {sup 223}Ra, {sup 224}Ra and {sup 226}Ra in marine water of the Itamaraca coastal region, PE, were measured during the winter of 2004, aiming to investigate the presence of radionuclides as a tracer of submarine groundwater discharges (SGD) in the environment studied. Measurements of temperature, salinity and nutrients were also carried out. (author)

  3. {sup 137}Cs accumulation in coastal sediments in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, H.B.L.; Salih, I. [Linkoeping Univ. (Sweden). Dept. of Radiation Physics; Herrmann, J. [Federal Maritime and Hydrographic Agency, Hamburg (Germany)

    2005-09-15

    Seabed sediment samples were collected in 1998, 2000 and 2001 at 20 sites located in the Baltic Sea and 4 sites in the Skagerrak. The objectives of the sampling campaigns were (i) to establish the coastal sediment distribution of {sup 137}Cs, (ii) to evaluate the vertical core distribution of {sup 137}Cs, (iii) to study the sediment accumulation rates, and (iv) to assess the sediment inventories of {sup 137}Cs. The results show a very high variation in {sup 137}Cs concentrations and an almost 100-fold difference in inventories, showing predominance of Chernobyl derived {sup 137}Cs in the Baltic Proper compared to the western Baltic and the Skagerrak areas. Sediment accumulation rates were highly dependent on sediment types and ranged from 0.05 to 1.8 cm/y.

  4. Determination of {sup 135}Cs by accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, C.M.; Charles, C.R.J. [Andre. E. Lalonde AMS Laboratory, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Department of Earth Sciences, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Zhao, X.-L.; Kieser, W.E. [Andre. E. Lalonde AMS Laboratory, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Cornett, R.J. [Andre. E. Lalonde AMS Laboratory, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Department of Earth Sciences, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Litherland, A.E. [IsoTrace Laboratory, University of Toronto, 60 St. George St., Toronto, ON M5S 1A7 (Canada)

    2015-10-15

    The ratio of anthropogenic {sup 135}Cs and {sup 137}Cs isotopes is characteristic of a uranium fission source. This research evaluates the technique of isotope dilution (yield tracing) for the purpose of quantifying {sup 135}Cs by accelerator mass spectrometry with on-line isobar separation. Interferences from Ba, Zn{sub 2}, and isotopes of equal mass to charge ratios were successfully suppressed. However, some sample crosstalk from source contamination remains. The transmission and di-fluoride ionization efficiencies of Cs isotopes were found to be 8 × 10{sup −3} and 1.7 × 10{sup −7} respectively. This quantification of {sup 135}Cs using yield tracing by accelerator mass spectrometry shows promise for future environmental sample analysis once the issues of sample crosstalk and low efficiency can be resolved.

  5. Sediment environmental capacity of 137Cs in Daya Bay

    Institute of Scientific and Technical Information of China (English)

    ZHANG Junli; CHEN Jiajun; XU Jialin; LI Yuanxin; HUANG Naiming

    2007-01-01

    Sediment environmental capacity of pollutants is very important for marine environmental management.Based on the methodology of a study on water,soil environmental capacity,and mass conservation theory in a system,the concept and model on sediment environmental capacity for 137Cs in Daya Bay were developed.The static capacity for 137Cs in the upper sediment near the shore at a shallow area was calculated,and the annual dynamic capacity and total dynamic capacity were also calculated through determination of the typical biomass in the sediment.The results showed that the estimated environmental capacity for 137Cs in sediments was approximately equal to the current input of 137Cs into the sediments.Controlling the input of 137Cs in the sediments within the environmental capacity guarantees the sustainability of the current situation of the Daya Bay ecosystem and avoidance of a significant degradation of the system.

  6. Selective extraction of naturally occurring radioactive Ra2+ from aqueous waste streams

    NARCIS (Netherlands)

    van Leeuwen, F.W.B.

    2005-01-01

    This thesis describes the design and selectivity of new Ra2+ extractants. The results presented provide insight in both the requirements needed to give Ra2+ selectivity and in the achievable Ra2+/Mn+ (Mn+ = alkali(ne earth) cation) separations.

  7. Effect of Potassium on Uptake of 137Cs in Food Crops Grown on Coral Soils: Annual Crops at Bikini Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Stone, E R; Robinson, W

    2002-02-01

    In 1954 a radioactive plume from the thermonuclear device code named BRAVO contaminated the principal residential islands, Eneu and Bikini, of Bikini Atoll (11{sup o} 36 minutes N; 165{sup o} 22 minutes E), now part of the Republic of the Marshall Islands. The resulting soil radioactivity diminished greatly over the three decades before the studies discussed below began. By that time the shorter-lived isotopes had all but disappeared, but strontium-90 ({sup 90}Sr), and cesium-137, ({sup 137}Cs) were reduced by only one half-life. Minute amounts of the long-lived isotopes, plutonium-239+240 ({sup 239+240}Pu) and americium-241 ({sup 241}Am), were present in soil, but were found to be inconsequential in the food chain of humans and land animals. Rather, extensive studies demonstrated that the major concern for human health was {sup 137}Cs in the terrestrial food chain (Robison et al., 1983; Robison et al., 1997). The following papers document results from several studies between 1986 and 1997 aimed at minimizing the {sup 137}Cs content of annual food crops. The existing literature on radiocesium in soils and plant uptake is largely a consequence of two events: the worldwide fallout of 1952-58, and the fallout from Chernobyl. The resulting studies have, for the most part, dealt either with soils containing some amount of silicate clays and often with appreciable K, or with the short-term development of plants in nutrient cultures.

  8. Experiences with the determination of Sr-89 and Sr-90 using fast methods; Erfahrungen bei der Bestimmung von {sup 89}Sr und {sup 90}Sr mittels Schnellmethoden

    Energy Technology Data Exchange (ETDEWEB)

    Kowalik, C.; Fueger, J. [Thueringer Landesanstalt fuer Umwelt und Geologie, Jena (Germany). Landesmessstelle fuer Umweltradioaktivaet

    2014-01-20

    Quick methods of the measurement of {sup 89}Sr and {sup 90}Sr have a great importance in the supervision of the environmental radioactivity. It is necessary to receive in short time dependable analytical data to be able to carry out suitable assessments or to give recommendations. The aim of the investigations was to be guaranteed the demands for these methods (test preparation, measurement and evaluation). The use of the solid phase extraction by means of commercial Sr Resin trademark columns (4.4' (5')-Di-tert-butylcyclohexanol-18-kronen-6-aether) (Triskem) to the radiochemical separation of the Sr isotopes was suitable. The measurements occurred to the FHT 770 T12 - Multi Low Level Alpha/Beta Sample Counter (Thermo Scientific). The results contain the summary activities of all available Sr isotopes, as for example {sup 89}Sr and {sup 90}Sr. The calculations of the single activities occur about the mathematical algorithm of the linear development on the basis of the works of G. Kanisch. The first results show, this method is suitable for the analysis of {sup 89}Sr and {sup 90}Sr and is used therefore in future in Thuringia.

  9. Bacterial CS2 Hydrolases from Acidithiobacillus thiooxidans Strains Are Homologous to the Archaeal Catenane CS2 Hydrolase

    NARCIS (Netherlands)

    Smeulders, M.J.; Pol, A. van der; Venselaar, H.; Barends, T.R.; Hermans, J.; Jetten, M.S.M.; Camp, H.J.M. op den

    2013-01-01

    Carbon disulfide (CS2) and carbonyl sulfide (COS) are important in the global sulfur cycle, and CS2 is used as a solvent in the viscose industry. These compounds can be converted by sulfur-oxidizing bacteria, such as Acidithiobacillus thiooxidans species, to carbon dioxide (CO2) and hydrogen sulfide

  10. Separation of {sup 134}Cs and {sup 137}Cs from {sup 125}I solution for medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Ram, Ramu; Dash, Ashutosh [Bhabha Atomic Research Centre, Trombay, Mumbai (India). Isotope Production and Applications Div.; Banerjee, Dayamoy [Bhabha Atomic Research Centre, Trombay, Mumbai (India). Process Development Div.

    2015-06-01

    While neutron irradiation of natural Xe gas followed by wet chemical dissolution of activation products constitutes a successful paradigm for the small scale production {sup 125}I, the concomitant production of {sup 134}Cs and {sup 137}Cs emerged as the primary impediment which necessitates purification of {sup 125}I solution. This paper describes an ion-exchange chromatographic technique using Resorcinol Formaldehyde (RF) resin to purify {sup 125}I solution from {sup 134}Cs and {sup 137}Cs impurities. A thorough investigation of the adsorption parameters of RF resin was carried out to arrive at the experimental conditions resulting optimum retention of {sup 134}Cs and {sup 137}Cs impurities. Based on the experimental findings, an optimized separation procedure was developed in which the neutron irradiated dissolved products at pH ∝ 13 was passed through a chromatography column containing RF resin where in {sup 134}Cs and {sup 137}Cs impurities gets adsorbed leaving behind {sup 125}I to appear in the effluent. The overall recovery of {sup 125}I was >90% with acceptable purity amenable for clinical applications.

  11. The CsBr-AlBr3 Phase Diagram and The Crystal Structure of CsAlBr4

    DEFF Research Database (Denmark)

    Berg, Rolf W.

    1997-01-01

    The phase diagram in the CsBr-AlBr3 system has been reinvestigated. An adjusted liquidus diagram is given, showing the compound CsAlBr4 which melts congruently at 360 oC. The lack of consistency among previous results is presumably due to the presence of oxide impurities formed by attack of bromide...

  12. Rapid determination of {sup 135}Cs and precise {sup 135}Cs/{sup 137}Cs atomic ratio in environmental samples by single-column chromatography coupled to triple-quadrupole inductively coupled plasma-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Guosheng [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan); Division of Nuclear Technology and Applications, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Beijing Engineering Research Center of Radiographic Techniques and Equipment, Beijing 100049 (China); Tazoe, Hirofumi [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan); Yamada, Masatoshi, E-mail: myamada@hirosaki-u.ac.jp [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan)

    2016-02-18

    For source identification, measurement of {sup 135}Cs/{sup 137}Cs atomic ratio not only provides information apart from the detection of {sup 134}Cs and {sup 137}Cs, but it can also overcome the application limit that measurement of the {sup 134}Cs/{sup 137}Cs ratio has due to the short half-life of {sup 134}Cs (2.06 y). With the recent advancement of ICP-MS, it is necessary to improve the corresponding separation method for rapid and precise {sup 135}Cs/{sup 137}Cs atomic ratio analysis. A novel separation and purification technique was developed for the new generation of triple-quadrupole inductively coupled plasma-mass spectrometry (ICP-MS/MS). The simple chemical separation, incorporating ammonium molybdophosphate selective adsorption of Cs and subsequent single cation-exchange chromatography, removes the majority of isobaric and polyatomic interference elements. Subsequently, the ICP-MS/MS removes residual interference elements and eliminates the peak tailing effect of stable {sup 133}Cs, at m/z 134, 135, and 137. The developed analytical method was successfully applied to measure {sup 135}Cs/{sup 137}Cs atomic ratios and {sup 135}Cs activities in environmental samples (soil and sediment) for radiocesium source identification. - Highlights: • A simple {sup 135}Cs/{sup 137}Cs analytical method was developed. • The separation procedure was based on AMP adsorption and one column chromatography. • {sup 135}Cs/{sup 137}Cs was measured by ICP-MS/MS. • Decontamination factors for Ba, Mo, Sb, and Sn were improved. • {sup 135}Cs/{sup 137}Cs atomic ratios of 0.341–0.351 were found in Japanese soil samples.

  13. The clinical significance of the anti-RA33 level in patients with rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Mehmet Türkmen

    2016-12-01

    Full Text Available Objective: The early diagnosis of Rheumatoid Arthritis (RA is of due significance for the prevention of possible damage to the joint tissue by means of treatment. Laboratory tests are very important for monitoring RA activity and for the evaluation of the patients’ response to the treatment. Rheumatoid factor, so far the most commonly used test for the cases with suspected RA, is not a specific parameter despite its sensitivity to RA. The measurement of other autoantibodies might be helpful to the diagnosis particularly for the cases with low RF titer or with suspected diagnosis. The measurement of anti-RA33 autoantibodies is one of the tests used in the diagnosis of the RA cases. The present study was conducted to compare anti-RA33 levels of healthy individuals with long-term RA cases and to evaluate the value of anti-RA33 test for the RA diagnosis. Method: Total 40 patients (28 female and 12 male identified with RA at least for the last five years according to the classification criteria of American College of Rheumatology (ACR reviewed in 1987 and 40 healthy controls included in the present study. Results: AntiRA-33 level was determined as 12.47±4.97 U/mL for the patients with RA and as 1.96±1.82 U/mL for the healthy controls, and there is no statistically significant difference between the groups. Conclusions: As a result AntiRA-33 level was evaluated in RA patients and no difference was found compared to control group.

  14. Particle mixing rates in sediments of the eastern equatorial Pacific: Evidence from 210Pb, 239,240Pu and 137Cs distributions at MANOP sites

    Science.gov (United States)

    Cochran, J. Kirk

    1985-05-01

    Particle mixing rates ( DB) calculated from excess 210Pb gradients in sediments of the east equatorial Pacific range from 0.04 to 0.5 cm 2/y, with variation of a factor of 3-4 at a single site. Diffusion of the 236Ra daughter 222Rn may affect 210Pb distributions under conditions of slow mixing and low 210Pb flux to the seafloor, as shown by a siliceous ooze-clay core which contained the fallout radionuclides 239,240Pu and 137Cs but no excess 210Pb (relative to 226Ra). There is no clear relationship between 210Pbderived mixing rates and sediment type, accumulation rate or organic carbon flux to the sediments. Comparison of 210Pb mixing rates with those calculated from 239,240Pu and 137Cs distributions reveals better agreement for a pulse input of the fallout radionuclides ( DB = 0.03-0.4 cm2/ y) than for continuous input at a constant rate ( DB = 0.1-1.6 cm2/ y), although the Pu and 137Cs data are better fit by the latter model. The agreement may be fortuitous because 239,240Pu and 137Cs appear significantly deeper than 210Pb in at least one core. Tracer separation could be caused by particle size-selective mixing by the benthic fauna or by chemical mobilization. If the fallout radionuclides are scavenged from surface waters by large, organic-rich particles such as fecal pellets, their release and migration may result from decomposition of the carrier in surface sediments. Either a relatively unreactive form of Pu (e.g. oxidized Pu) has been released by this process or a one-dimensional model is inadequate to explain its observed penetration into the sediments. Activity ratios of 239,240Pu /137Cs in the sediments decrease with increasing north latitude, and the trend reflects higher fluxes of 239,240Pu near the weapons test site at Christmas Island (2°N). The 239,240Pu /137Cs ratios and fluxes to the sediment (assuming constant input) at the siliceous ooze-red clay site are consistent with published sediment trap data from a nearby site. Thus if fallout

  15. High Resolution Study of the 222Ra Exotic Decay

    Science.gov (United States)

    Hussonnois, M.; Le Du, J. F.; Brillard, L.; Dalmasso, J.; Ardisson, G.

    1991-10-01

    The 14C-decay of 222Ra has been reinvestigated using a strong 230U source and the magnetic superconducting spectrometer SOLENO in view of looking for a possible feeding of the first 208Pb excited state. 210 14C-events were recorded in a single peak of (30.930±0.090) MeV energy; the 14C branching ratio values b=(2.31±0.31)×10-10 and <1×10-12 to the respective 208Pb ground and Iπ=3- octupole state were deduced.

  16. Endoparasitismo gastrintestinal em cabras da raça Anglonubiana

    OpenAIRE

    Batista,Joilson Ferreira; Campelo,José Elivalto Guimarães; Morais,Marcyele Ferreira; Silva,Pollyana Oliveira; Magalhães,Pâmela Cristina; Barçante,Felipe Pereira da Silva; Mendonça,Ivete Lopes

    2014-01-01

    A dificuldade de manutenção do rebanho em condições sanitárias adequada compromete a eficiência da criação de caprinos, principalmente em relação ao controle de endoparasitas. O objetivo com este trabalho foi avaliar a sensibilidade de matrizes da raça Anglonubiana a nematoides gastrintestinais, considerando as cabras estratificadas por estágio fisiológico (lactantes e não lactantes) dentro de três classes de idade. Utilizou-se as características: Ovos por grama de fezes (OPG), Grau de anemia...

  17. Bedside etiology of childhood cancer. [X radiation, /sup 224/Ra

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.W.

    1977-01-01

    The following topics are discussed: adenocarcinomas of the vagina in young women exposed prenatally to diethylstilbestrol; neuroblastoma in children exposed prenatally to hydantoin; increased frequency of leukemia in Japanese children surviving the atomic bomb; cancer in adults following administration of /sup 224/Ra during childhood; increased risk of lung cancer following environmental exposure of children to asbestos; lung cancer in adults following exposure to lead, copper, zinc, and arsenic; association of chromosomal aberrations with leukemia in children exposed to x radiation and benzene; immunosuppression in lymphoma patients; renal dysplasia in patients with Wilms' tumor; and aggregation of neoplasms in families. (HLW)

  18. Atomic Mass and Nuclear Binding Energy for Ra-226 (Radium)

    Science.gov (United States)

    Sukhoruchkin, S. I.; Soroko, Z. N.

    This document is part of the Supplement containing the complete sets of data of Subvolume B `Nuclei with Z = 55 - 100' of Volume 22 `Nuclear Binding Energies and Atomic Masses' of Landolt-Börnstein - Group I `Elementary Particles, Nuclei and Atoms', and additionally including data for nuclei with Z = 101 - 130. It provides atomic mass, mass excess, nuclear binding energy, nucleon separation energies, Q-values, and nucleon residual interaction parameters for atomic nuclei of the isotope Ra-226 (Radium, atomic number Z = 88, mass number A = 226).

  19. Raça ovina Merino da Beira Baixa

    OpenAIRE

    Andrade, C.S.C.R.; Pires, T. H. S.

    2012-01-01

    O Merino da Beira Baixa é um animal cujas características fenotípicas estão estabelecidas e que se fixaram após um período evolutivo de cruzamentos das raças autóctones existentes a quando do Recenseamento Geral de Gados de 1870, bordaleiro churro e comum, com o Merino Espanhol introduzido em Portugal em 1920, o Merino Fonte Boa em 1929/30 e devido a transumâncias com os churros Mondegueiro e Serra da Estrela (6). A sua substituição por outras, teoricamente mais produtivas mas ...

  20. Ra and the average effective strain of surface asperities deformed in metal-working processes

    DEFF Research Database (Denmark)

    Bay, Niels; Wanheim, Tarras; Petersen, A. S

    1975-01-01

    Based upon a slip-line analysis of the plastic deformation of surface asperities, a theory is developed determining the Ra-value (c.l.a.) and the average effective strain in the surface layer when deforming asperities in metal-working processes. The ratio between Ra and Ra0, the Ra-value after...... and before deformation, is a function of the nominal normal pressure and the initial slope γ0 of the surface asperities. The last parameter does not influence Ra significantly. The average effective strain View the MathML sourcege in the deformed surface layer is a function of the nominal normal pressure...

  1. (90)Sr in fish from the southern Baltic Sea, coastal lagoons and freshwater lake.

    Science.gov (United States)

    Zalewska, Tamara; Saniewski, Michał; Suplińska, Maria; Rubel, Barbara

    2016-07-01

    Activity concentrations of radioactive (90)Sr were studied in four fish species: herring, flounder, sprat and cod caught in the southern Baltic Sea in two periods: 2005-2009 and 2013-2014. The study included also perch from the coastal lagoons - Vistula Lagoon and Szczcin Lagoon and a freshwater lake - Żarnowieckie Lake as well as additional lake species: pike and bream. (90)Sr activity concentrations were compared in relation to species and to particular tissue: muscle, whole fish (eviscerated) and bones. In 2014, in the Baltic, the maximal (90)Sr concentrations were found in fishbones: herring - 0.39 Bq kg(-1) w.w., cod - 0.48 Bq kg(-1) w.w., and flounder - 0.54 Bq kg(-1) w.w. In the whole fish the maximal concentrations were found in flounder - 0.16 Bq kg(-1) w.w. and cod - 0.15 Bq kg(-1) w.w., while in herring - 0.022 Bq kg(-1) w.w. and sprat - 0.026 Bq kg(-1) w.w. they stayed at lower level. Relatively high (90)Sr concentrations were detected in whole fish from freshwater Lake Żarnowieckie: perch - 0.054 Bq kg(-1) w.w., pike - 0.062 Bq kg(-1) w.w. and bream - 0.140 Bq kg(-1) w.w. Concentration ratio (CR) determined for particular fish tissues and for whole eviscerated fish in relation to (90)Sr concentrations in seawater and lake water were showing significant variability unlike the corresponding (137)Cs concentration ratios which are stable and specific for fish species. The study corroborates with the conviction of the growing role of (90)Sr in the overall radioactivity in the southern Baltic Sea as compared to (137)Cs.

  2. First Test Results on ITER CS Model Coil and CS Insert

    Energy Technology Data Exchange (ETDEWEB)

    Martovetsky, N; Michael, P; Minervini, J; Radovinsky, A; Takayasu, M; Thome, R; Ando, T; Isono, T; Kato, T; Nakajima, H; Nishijima, G; Nunoya, Y; Sugimoto, M; Takahashi, Y; Tsuji, H; Bessette, D; Okuno, K; Ricci, M; Maix, R

    2000-10-12

    The Inner and Outer modules of the Central Solenoid Model Coil (CSMC) were built by US and Japanese home teams in collaboration with European and Russian teams to demonstrate the feasibility of a superconducting Central Solenoid for ITER and other large tokamak reactors. The CSMC mass is about 120 t, OD is about 3.6 m and the stored energy is 640 MJ at 46 kA and peak field of 13 T. Testing of the CSMC and the CS Insert took place at the Japan Atomic Energy Research Institute (JAERI) from mid March until mid August 2000. This paper presents the main results of the tests performed.

  3. Physics Design for ARIES-CS

    Energy Technology Data Exchange (ETDEWEB)

    L.P. Ku, P.R. Garabedian, J. Lyon, A. Turnbull, A. Grossman, T.K. Mau, M. Zarnstorff, and the ARIES Team

    2007-10-10

    Novel stellarator configurations have been developed for ARIES-CS. These configurations are optimized to provide good plasma confinement and flux surface integrity at high beta. Modular coils have been designed for them in which the space needed for the breeding blanket and radiation shielding was specifically targeted such that reactors generating GW electrical powers would require only moderate major radii (<10 m). These configurations are quasi-axially symmetric in the magnetic field topology and have small number of field periods (≤3) and low aspect ratios (≤6). The baseline design chosen for detailed systems and power plant studies has 3 field periods, aspect ratio 4.5 and major radius 7.5 m operating at β~6.5% to yield 1 GW electric power. The shaping of the plasma accounts for ≥75% of the rotational transform. The effective helical ripples are very small (< 0.6% everywhere) and the energy loss of alpha particles is calculated to be ≤5% when operating in high density regimes. An interesting feature in this configuration is that instead of minimizing all residues in the magnetic spectrum, we preferentially retained a small amount of the non-axisymmetric mirror field. The presence of this mirror and its associated helical field alters the ripple distribution, resulting in the reduced ripple-trapped loss of alpha particles despite the long connection length in a tokamak-like field structure. Additionally, we discuss two other potentially attractive classes of configurations, both quasi-axisymmetric: one with only two field periods, very low aspect ratios (~2.5), and less complex coils, and the other with the plasma shaping designed to produce low shear rotational transform so as to assure the robustness and integrity of flux surfaces when operating at high β.

  4. Influence of water management and fertilizer application on (137)Cs and (133)Cs uptake in paddy rice fields.

    Science.gov (United States)

    Wakabayashi, Shokichi; Itoh, Sumio; Kihou, Nobuharu; Matsunami, Hisaya; Hachinohe, Mayumi; Hamamatsu, Shioka; Takahashi, Shigeru

    2016-06-01

    Cesium-137 derived from the Tokyo Electric Power Company's Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident contaminated large areas of agricultural land in Eastern Japan. Previous studies before the accident have indicated that flooding enhances radiocesium uptake in rice fields. We investigated the influence of water management in combination with fertilizers on (137)Cs concentrations in rice plants at two fields in southern Ibaraki Prefecture. Stable Cs ((133)Cs) in the plants was also determined as an analogue for predicting (137)Cs behavior after long-term aging of soil (137)Cs. The experimental periods comprised 3 y starting from 2012 in one field, and 2 y from 2013 in another field. These fields were divided into three water management sections: a long-flooding section without midsummer drainage, and medial-flooding, and short-flooding sections with one- or two-week midsummer drainage and earlier end of flooding than the long-flooding section. Six or four types of fertilizer subsections (most differing only in potassium application) were nested in each water management section. Generally, the long-flooding treatment led to higher (137)Cs and (133)Cs concentrations in both straw and brown rice than medial- and short-flooding treatments, although there were some notable exceptions in the first experimental year at each site. Effects of differing potassium fertilizer treatments were cumulative; the effects on (137)Cs and (133)Cs concentrations in rice plants were not obvious in 2012 and 2013, but in 2014, these concentrations were highest where potassium fertilizer had been absent and lowest where basal dressings of K had been tripled. The relationship between (137)Cs and (133)Cs in rice plants was not correlative in the first experimental year at each site, but correlation became evident in the subsequent year(s). This study demonstrates a novel finding that omitting midsummer drainage and/or delaying drainage during the grain-filling period enhances

  5. 解剖CS:S de_inferno

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    CS:Source de_inferno区域分析inferno A区的变化较大,根据CS:Source地图制作的特点(每个地图都需确定一个主题),原来CS的箱子加黄色风格变成了庄园加绿色风格。在地图细节上, CS:S inferno在不修改CS地图原有距离关系的前提下,添加了大量局部细节和变化,比如2楼、阳台、

  6. Scintillation, Afterglow and Thermoluminescence of CsI:Tl,Sm

    Science.gov (United States)

    Kappers, L. A.; Bartram, R. H.; Hamilton, D. S.; Lempicki, A.; Brecher, C.; Gaysinskiy, V.; Ovechkina, E. E.; Nagarkar, V. V.

    2010-11-01

    Experiments on co-doped CsI:Tl,Sm suggest that samarium electron traps scavenge electrons from thallium traps and that electrons subsequently released by samarium recombine non-radiatively with trapped holes, thus suppressing afterglow. These experiments support the inference that electrons tunnel freely between samarium ions and are trapped preferentially as substitutional Sm+ near VKA(Tl+) centers where non-radiative recombination is the rate-limiting step. Combined radioluminescence, afterglow and thermoluminescence on single-crystal samples of CsI:Tl and CsI:Tl,Sm, recorded sequentially at adjusted gain settings following low-temperature irradiation, reveal reversible radiation damage as well.

  7. The transfer of {sup 137}Cs from barley to beer

    Energy Technology Data Exchange (ETDEWEB)

    Proehl, G.; Mueller, H.; Voigt, G. [Institut fuer Strahlenschutz, Oberschleibheim (Germany)] [and others

    1997-01-01

    Beer has been brewed from barley contaminated with {sup 137}Cs as a consequence of the Chernobyl accident. The {sup 137}Cs activity has been measured in all intermediate steps and in the by-products of the production process. About 35 % of the {sup 137}Cs in barley were recovered in beer. Processing factors defined as the concentration ratio of processed and raw products were determined to be 0.61, 3.3, 0.1 and 0.11 for malt, malt germs, spent grains and beer, respectively. 4 refs., 2 tabs.

  8. [ICO-166 monoclonal antibodies against the CD45RA antigen].

    Science.gov (United States)

    Frolova, E A; Baryshnikov, A Iu; Novikov, V V; Syrkin, A B

    1993-07-01

    Monoclonal antibodies (MCA) ICO-166 against CD45RA antigen were generated and characterized. In the indirect IFA, MCA ICO-166 reacted with 54.1 +/- 1.9% lymphocytes of human peripheral blood and 15.2 +/- 2.3% monocytes but not with granulocytes or thrombocytes. The method of double labelling of cells demonstrated that MCA ICO-166 detected all B-lymphocytes, all NK-cells and 31% of mature T-lymphocytes but only 55% of CD8 suppressor cells and only 21% of CDA helper cells carried this antigen on the surface. Experiments were carried out to block binding of FITC-labeled MCA ALB11 against CD45RA antigen with human lymphocytes by pretreatment of cells with different concentrations of MCA ICO-166. Treatment of cells with MCA ALB11 blocked binding of MCA ALB11-FITC by 85% on the average. MCA ICO-166 blocked binding of MCA ALB11-FITC by 66% on the average. When different dilutions of MCA ICO-166 were used, the dose-dependent effect of blocking of MCA ALB11-FITC binding was observed. MCA ICO-166 immunoprecipitated a protein band of molecular weight 220 kDa from lysates of mononuclear cells of the human peripheral blood.

  9. Early electroretinografic changes in elderly RA patients treated with hydroxychloroquine

    Directory of Open Access Journals (Sweden)

    C. Gelmi

    2011-09-01

    Full Text Available Objective: to evaluate the effectiveness of fundoscopy, electrooculography, electroretinogram and visually evoked potentials in early detection of hydroxychloroquine retinal toxicity in RA patients and to evaluate the influence of patients’ age, drug dosage, concomitant therapy (prednisone and methotrexate and serum creatinine levels in the development of this side effect. Methods: from september to december 1999, we have enrolled 32 RA patients (13 males, 19 females starting hydroxichlorochine treatment. The patients underwent regular ophthalmological examination (fundoscopy, electro-oculography, electro-retinogram and visually evoked potentials every 4 months. Disease activity was evaluated every two months by clinical and routine serological examination. Results: no patients developed retinopathy during 1 year’s follow-up; fundoscopy, electrooculography, and visually evoked potentials did not vary from the baseline. On the other hand, electroretinogram showed early alterations of scotopic and photopic response; moreover a significant statistical correlation between patients’ age (more than 65 years and b1 photopic wave increase (p < 0,05 was observed. No correlation was found between the developement of electro- retinographic alterations and hydroxychloroquine dosage, concomitant therapy and serum creatinine levels Conclusion: our data show the inefficacy of fundoscopy, electrooculography and visually evoked potentials in early detection of hydroxychloroquine retinopathy. On the other hand electroretinogram allows early detection of retinal alterations during hydroxychloroquine treatment, in patients older than 65 years.

  10. Atomic parity violation in a single Ra ion

    Energy Technology Data Exchange (ETDEWEB)

    Nunes Portela, M.; Beker, H.; Giri, G.; Jungmann, K.; Onderwater, C.J.G.; Schlesser, S.; Timmermans, R.G.E.; Versolato, O.O.; Willmann, L.; Wilschut, H.W. [KVI, University of Groningen, NL (Germany)

    2012-07-01

    Precision measurements of atomic parity violation is the only path to determine the electroweak mixing angle in the Standard Model of particle physics at low energy scale. A single trapped Ra{sup +} ion is the most promising candidate for such an experiment. The system combines the advantages of large parity violation amplitudes due to the faster than Z{sup 3} scaling, the possibility to perform accurate atomic structure calculation on this one valence electron system and the ability to precision frequency measurements on trapped ion. Our first laser spectroscopy on an ensemble of trapped short-lived {sup 209-214}Ra{sup +} isotopes in a linear Paul trap provided hyperfine structure of the 6d {sup 2}D{sub 3/2} states and isotope shift of the 6d {sup 2}D{sub 3/2} - 7p {sup 2}P{sub 1/2} transition. These results provide input for the ongoing precision atomic structure calculations. The next step of the experiments towards laser cooling of a single trapped radium ion. The experimental setup is being commissioned with Ba ions.

  11. Raúl Castro a la hora de las decisiones

    Directory of Open Access Journals (Sweden)

    Janette HABEL

    2010-01-01

    Full Text Available Este artículo trata sobre el nuevo rol político de Raúl Castro en Cuba. Su misión no es fácil. Debe redefinir un proyecto de desarrollo viable en condiciones históricas y geopolíticas nuevas; garantizar la estabilidad del país; organizar el relevo entre los antiguos dirigentes históricos y las nuevas generaciones; y, además, iniciar negociaciones con la administración Obama. ¿Se podrá hablar en adelante de un «raulismo» o se seguirá imponiendo el «fidelismo»? Asimismo, ¿cómo salvaguardar la soberanía e independencia, junto a las principales conquistas sociales desde hace cincuenta años, mientras al mismo tiempo se llevan a cabo las reformas «estructurales » y se intenta normalizar relaciones con el continente, específicamente con Estados Unidos? Esa respuesta, que no es obvia, la debe dar Raúl Castro.

  12. Spatial uncertainty of the 137Cs reference inventory for Australian soil

    National Research Council Canada - National Science Library

    Adrian Chappell; Gary Hancock; Raphael A. Viscarra Rossel; Robert Loughran

    2011-01-01

      First national, hillslope scale assessment of 137Cs reference inventory Spatial uncertainty of 137Cs reference inventory for propagation in models Baseline 137Cs reference inventory can be updated...

  13. Syntheses, structures, and optical properties of the indium/germanium selenides Cs4In8GeSe16, CsInSe2, and CsInGeSe4

    Science.gov (United States)

    Ward, Matthew D.; Pozzi, Eric A.; Van Duyne, Richard P.; Ibers, James A.

    2014-04-01

    The three solid-state indium/germanium selenides Cs4In8GeSe16, CsInSe2, and CsInGeSe4 have been synthesized at 1173 K. The structure of Cs4In8GeSe16 is a three-dimensional framework whereas those of CsInSe2 and CsInGeSe4 comprise sheets separated by Cs cations. Both Cs4In8GeSe16 and CsInGeSe4 display In/Ge disorder. From optical absorption measurements these compounds have band gaps of 2.20 and 2.32 eV, respectively. All three compounds are charge balanced.

  14. Impact of {sup 134}Cs and {sup 137}Cs from the Chernobyl reactor accident on the Spanish Mediterranean marine environment

    Energy Technology Data Exchange (ETDEWEB)

    Molero, J.; Sanchez-Cabeza, J.A.; Merino, J. [Grup de Fisica de les Radiacions, Departament de Fisica, Facultat de Ciencies, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Mitchell, P.I. [Laboratory of Radiation Physics, University College, Dublin (Ireland); Vidal-Quadras, A. [Grup de Fisica de les Radiacions, Departament de Fisica, Facultat de Ciencies, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain)

    1999-05-01

    As part of a study aiming to establish the distribution and bioavailability of man-made radionuclides in the marine environment, radiocaesium levels were determined in large volume sea water samples and in the sea-grass Posidonia oceanica collected along the Spanish Mediterranean coast. Results obtained from 1987 to 1991 showed the enhancement of radiocaesium levels in the Spanish Mediterranean marine environment after the Chernobyl accident. The well-known {sup 134}Cs/{sup 137}Cs isotopic ratio in Chernobyl fresh deposition was used to identify the weapon tests fall-out and Chernobyl deposition components. {sup 137}Cs and {sup 134}Cs mean concentrations in surface waters from the Spanish Mediterranean shoreline were 4.8{+-}0.2 and 0.27{+-}0.01 Bq m{sup -3}, respectively. {sup 137}Cs concentration incorporated into Mediterranean waters as a consequence of the post-Chernobyl deposition was estimated to be 1.16{+-}0.04 Bq m{sup -3}, which is a 33{+-}2% increase over the previous levels. {sup 137}Cs estimated inventory in the surface water layer (0-50 m) of the Catalan-Balearic basin was 17.4{+-}0.5 TBq for {sup 137}Cs, of which 4.3{+-}0.2 TBq must be attributed to post-Chernobyl deposition, and 1.00{+-}0.04 TBq for {sup 134}Cs. Activation and fission products such as {sup 106}Ru, {sup 110m}Ag, {sup 134}Cs, {sup 137}Cs and {sup 144}Ce, were detected in all samples of Posidonia oceanica. Mean radiocaesium levels in the bioindicator were 1.02{+-}0.25 and 0.20{+-}0.03 Bq kg{sup -1} for {sup 137}Cs and {sup 134}Cs, respectively, corresponding to a mean isotopic ratio {sup 134}Cs/{sup 137}Cs equal to 0.20{+-}0.04 (1987). {sup 137}Cs activity incorporated by Posidonia oceanica after the Chernobyl deposition over the Mediterranean Sea was estimated as 0.51{+-}0.08 Bq kg{sup -1}. Therefore, {sup 137}Cs specific activity had increased 100{+-}40% one year after the accident. Low level radioactive liquid effluents from the nuclear power plants located on the southern Catalan

  15. Geology and Chemical Characterization of the Ultrapotassic Peralkaline Magmatism of the Manaíra-Princesa Isabel Dike Swarm, Borborema Provine

    Directory of Open Access Journals (Sweden)

    Maria Helena Bezerra Maia de Hollanda

    2009-10-01

    Full Text Available The Manaíra-Princesa Isabel dike swarm forms one of the most expressive examples of Neoproterozoic (c. 600 Maperalkaline magmatism in the Borborema Province (NE Brazil. It consists of about a hundred NE-trending bodies intrusivein older, Neoproterozoic porphyritic granites (Princesa Isabel and Tavares plutons, and orthogneisses and low-grademetasediments of the Eo-neoproterozoic Riacho Gravatá complex. The dike swarm includes mostly silica-saturated syenites,with potassic to ultrapotassic, peralkaline affinity, containing microcline and sodic amphibole ± pyroxene as the mainmineral assemblage. Amphibole is dominantly Mg-riebeckite (Manaíra, Princesa Isabel and Tavares sub-swarms, whereaspyroxene is mainly aegirine-augite (Manaíra and Tavares sub-swarms. A minor set of dikes from this swarm is slightlymetaluminous with Mg-biotite as the major mafic phase. Geochemical and isotopic signatures indicate strong enrichmentin incompatible elements (Rb, Ba, K, Th, U, in association with a negative Nb anomaly, and strongly radiogenic 87Sr/86Srand 143Nd/144Nd (= negative εNd values initial ratios. These features suggest a common source, which was probably an enriched lithospheric mantle reservoir, chemically modifi ed by an ancient subduction component inferred to be Paleoproterozoic fromTDM model ages. Conversely, Pb isotopic ratios lower than average crustal values indicate the influence of a non-radiogenic componentinteracting with the enriched mantle source. A SHRIMP U-Pb age of c. 600 Ma obtained for the Manaíra-Princesa Isabel dike swarmdefi nes an important crustal exhumation period which was relatively synchronous with intensive tectonomagmatic activity related tothe Brasiliano orogeny, which occurred in distinct structural domains within the Transverse Zone of the Borborema Province.

  16. Epiphytic fruticose lichens as biomonitors for retrospective evaluation of the (134)Cs/(137)Cs ratio in Fukushima fallout.

    Science.gov (United States)

    Ramzaev, V; Barkovsky, A; Gromov, A; Ivanov, S; Kaduka, M

    2014-12-01

    In 2011-2013, sampling of epiphytic fruticose lichens of the genera Usnea, Bryoria and Alectoria was carried out on Sakhalin and Kuril Islands (the Sakhalin region, Russia) to investigate contamination of these organisms with the Fukushima-derived (134)Cs and (137)Cs. Activities of the radionuclides were determined in all 56 samples of lichens taken for the analysis. After correction for radioactive decay (on 15 March 2011), the activity concentrations ranged from 2.1 Bq kg(-1) (d.w.) to 52 Bq kg(-1) for (134)Cs and from 2.3 Bq kg(-1) to 52 Bq kg(-1) for (137)Cs. Cesium-134 and (137)Cs activities for the whole set of lichens (n = 56) were strongly positively correlated; Spearman's rank correlation coefficient was calculated as 0.991 (P lichens from the Sakhalin and Kunashir islands declined with a factor of three in the period from 2011 to 2013. The average biological half-time for both cesium radionuclides in lichens of the genus Usnea is estimated as 1.3 y. The mean of 0.99 ± 0.10 and median of 0.99 were calculated for the decay corrected (134)Cs/(137)Cs activities ratios in the lichens (n = 56). The radionuclides ratio in the lichens did not depend on location of sampling site, species and the time that had passed after the Fukushima accident. The regression analysis has shown the background pre-Fukushima level of (137)Cs of 0.4 ± 0.3 Bq kg(-1), whereas the ratio between the Fukushima-borne (134)Cs and (137)Cs in the lichens was estimated as 1.04. The (134)Cs/(137)Cs activities ratio in lichens from the Sakhalin region is consistent with the ratios reported by others for the heavy contaminated areas on Honshu Island in Japan following the Fukushima accident. The activity concentrations of natural (7)Be in lichens from the Sakhalin region varied between 100 Bq kg(-1) and 600 Bq kg(-1); the activity concentrations did not exhibit temporal variations during a 2y-period of observations. The applicability of epiphytic fruticose lichens as

  17. Sources and pathways of 90Sr in the North Atlantic-Arctic region: present day and global warming.

    Science.gov (United States)

    Gao, Yongqi; Drange, Helge; Johannessen, Ola M; Pettersson, Lasse H

    2009-05-01

    The spatial and temporal distributions of the anthropogenic radionuclides (137)Cs and (90)Sr, originating from nuclear bomb testing, the Sellafield reprocessing plant in the Irish Sea (UK), and from the Ob and Yenisey river discharges to the Arctic Ocean, have been simulated using the global version of the Miami Isopycnic Coordinate Ocean Model (MICOM). The physical model is forced with daily atmospheric re-analysis fields for the period of 1948-1999. Comparison of the temporal evolution of the observed and the simulated concentrations of (90)Sr has been performed in the Kara Sea. The relative contributions of the different sources on the temporal and spatial distributions of the surface (90)Sr are quantified over the simulated period. It follows that the Ob river discharge dominated the surface (90)Sr over most of the Arctic Ocean and along the eastern and western coasts of Greenland before 1960. During the period of 1980-1990, the atmospheric fallout and the Ob river discharge were equally important for the (90)Sr distribution in the Arctic Ocean. Furthermore, an attempt has been made to explore the possible dispersion of accidental released (90)Sr from the Ob and Yenisey rivers under a global warming scenario (2 x CO(2)). The difference between the present-day and the global warming scenario runs indicates that more of the released (90)Sr from the Ob and Yenisey rivers is confined to the Arctic Ocean in the global warming run, particularly in the near coastal, non-European part of the Arctic Ocean.

  18. Crystal structure of Cs2[Th(NO36

    Directory of Open Access Journals (Sweden)

    Patrick Woidy

    2014-08-01

    Full Text Available Dicaesium hexanitratothorate(IV, Cs2[Th(NO36], was synthesized in the form of colourless crystals by reaction of thorium nitrate and caesium nitrate in aqueous solution. The Th atom is located on an inversion centre and is coordinated by six chelating nitrate anions. The resulting ThO12 coordination polyhedron is best described as a slightly distorted icosahedron. The Cs atom also has a coordination number of 12, but its coordination polyhedron is considerably more distorted. The crystal packing can be derived from an hexagonal dense packing (hcp of idealized spherical CsO12 and ThO12 units. The CsO12 units form a distorted hcp arrangement and half of the octahedral sites are occupied by the ThO12 units.

  19. Fast light of CsI(Na) crystals

    Institute of Scientific and Technical Information of China (English)

    SUN Xi-Lei; FANG Jian; XIE Yu-Guang; AN Zheng-Hua; WANG Zhi-Gang; XUE Zhen; ZHANG Ai-Wu; LU Qi-Wen; NING Fei-Peng; GEYong-Shuai; LIU Ying-Biao; LU Jun-Guang; HU Tao; ZHOU Li; CAO Jun; WANG Yi-Fang; ZHAN Liang; YU Bo-Xiang; CAI Xiao

    2011-01-01

    The responses of different common alkali halide crystals to alpha-rays and gamma-rays are tested in this research.It is found that only CsI(Na) crystals have significantly different waveforms between alpha and gamma scintillations,while others do not exhibit this phenomena.The rise time of the fast light is about 5 ns and the decay time is 17±12 ns.It is suggested that the fast light of CsI(Na) crystals arises from the recombination of free electrons with self-trapped holes of the host crystal CsI.Self-absorption limits the emission of fast light of CsI(T1) and NaI(T1) crystals.

  20. Bioavailability pf radionuclides {sup 226}Ra, {sup 228}Ra and {sup 210}Pb present in Brazilian phosphogypsum and phosphate fertilizers

    Energy Technology Data Exchange (ETDEWEB)

    Russo, Ana Carolina; Saueia, Catia H.R.; Mazzilli, Barbara P., E-mail: chsaueia@ipen.br [Instituto de Pesquisas Energeticas e Nucleares(IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Phosphogypsum (PG) is a by-product of phosphate fertilizers industries. The USEPA classified PG as a - Technologically Enhanced Naturally Occurring Radioactive Material (TENORM). Its worldwide production on 2006 was estimated in 150 million tons. Annually the three main phosphate industries in Brazil are responsible for 5.5x106 tons of phosphogypsum, which is stored in stacks. The level of radionuclides present in phosphogypsum is well-known and makes its disposal or reutilization an environmental concern. Part of this byproduct can be reused, for example, to improve fertility of agricultural soils. To assess the long term environmental impact of radioactive contamination of ecosystems, information on source term including radionuclide speciation, mobility and biological uptakes have high importance. This paper intends to evaluate the bioavailability of the radionuclides {sup 226}Ra, {sup 228}Ra and {sup 210}Pb to the environment by following a procedure established by the EC (European Community), which includes a single EDTA-NH{sub 4} 0.05M extraction at pH 7.0 prior to the analyses. These results is compared with the total activity concentration of these radionuclides in Brazilian PG and the most used phosphate fertilizers (SSP, TSP, MAP and DAP). This procedure intends to represent on a more realistic way the leaching of radionuclides from PG and fertilizers to soil and agricultural products. (author)

  1. 黔东松桃南华系大塘坡组锰矿层物源:来自 Sr 同位素的证据%Provenance of Nanhuan Datangpo Formation Manganese Mn Deposit in Songtao Area,East Guizhou Province:Evidence from Sr Isotope

    Institute of Scientific and Technical Information of China (English)

    余文超; 齐靓; 杜远生; 周琦; 彭头平; 王萍; 袁良军; 徐源; 潘文; 谢小峰

    2016-01-01

    in Lower Nanhuan Datangpo Formation in Songtao,East Guizhou Province indicates that 87 Sr/86 Sr ratios in 15 samples vary in 0.705 727-0.732 536.Studied samples include Mn ore,Mn shale and black shale in the Mn-bearing layer and the highest 87 Sr/86 Sr ratio appears in the black shale sample.With Al (%)increasing in samples,87 Sr/86 Sr ratios show two changing trends:the rising trend indicates terrigenous materials input and the falling trend indicates the deep hydrothermal sources input.As to 87 Sr/86 Sr ratios via Mn (%),there is no significant correlation coefficient,but 87 Sr/86 Sr ra-tios decrease when Mn (%)increase generally,according to residual analysis,we find that this is caused by the convergence fluctuation of 87 Sr/86 Sr ratios against the Mn(%)changes.The broad variation of 87 Sr/86 Sr ratios in Mn layer is caused by the dual inputs from terrigenous materials and hydrothermal sources.Compared with the contemporary (about 660 Ma)Sr isotope ratio in paleoseawater and the Sr isotope data from different ages Mn deposit world wide,we find that the broad variation of 87 Sr/86 Sr ratios in the Datangpo For-mation.Mn layer does not conform to the feature of hydrogenetic Mn deposit.Considered with the specific geological background,we believe that the accumulation and precipitation of manganese are separated processes:the accumulation of Mn had finished in the anoxic basin during the Sturtian glaciation,whereas the Mn deposit precipitated in an unstable paleoceanographic environment at the beginning of interglaciation.

  2. "Young" Lukács: tragic, utopian and romantic?

    Directory of Open Access Journals (Sweden)

    Ester Vaisman

    Full Text Available Given the controversial character of "Young" Lukács' intellectual course, especially in what concerns the works Soul and Form and The theory of the novel, the main purpose of the present paper is to outline Lukács' course in his youth phase, based on his own texts and statements, aiming at questioning certain characteristics attributed to this important period of his intellectual production.

  3. /sup 137/Cs radioactive dating of Lake Ontario sediment cores

    Energy Technology Data Exchange (ETDEWEB)

    Ward, T.E.; Breeden, J.; Komisarcik, K.; Porter, R.; Czuczwa, J.; Kaminski, R.; McVeety, B.D.

    1987-12-01

    The distribution of /sup 137/Cs in sediment cores from Lake Ontario provides estimates of the sediment accumulation rates. Geochronology with /sup 210/Pb dating and distribution of Ambrosia (ragweed) pollen compare well with /sup 137/Cs dating. These methods can determine with precision, changes in sedimentation occurring over the past 100 years or so. Typical sedimentation rates of 0.18-0.36 cm/yr were measured. 16 refs., 3 figs., 2 tabs.

  4. Characteristics of 137Cs deposition in steppe area

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Soil wind erosion in the semiarid steppe area was studied using the 137Cs tracing technique. Comparisons of 137Cs deposition characteristics between different soil profiles indicated that slight aeolian activities occurred on sandy grasslands and semi-fixed dunes with erosion/deposition rates of less than 0.108 cm/a, whereas they were intense on semi-shifting dunes with erosion/deposition rates of higher than 1.35 cm/a.

  5. Obsah Cs-137 v houbách

    OpenAIRE

    ČADOVÁ, Michaela

    2015-01-01

    The aim of this work is to compare the presence of Cs-137 in different kinds of mushrooms in selected locations using semiconductor gamma-ray spectrometry. Research question was determined: Does Cs-137 content amount vary depending on the fungal species? The first part deals with basic knowledge of ionizing radiation, which is important for the complex understanding of thematic problems. This concerns basic radiobiological terms such as radioactivity, ionizing radiation, its biological effect...

  6. Zeeman Effect in the Electronic Spectrum of Solid CS2

    NARCIS (Netherlands)

    Hochstrasser, Robin M.; Wiersma, Douwe A.

    1971-01-01

    The lowest-energy 3A2←1Σg+ singlet-triplet transition of CS2 has been studied in the CS2 crystal at 4.2°K. The spectrum consists mainly of progressions in the bending mode ν2'. The following values for the upper state frequencies have been obtained (v1'=677 cm–1, ν2'=309 cm–1) and the unobserved B2

  7. Distribution of 226Ra in the Arctic Ocean and the Bering Sea and its hydrologic implications

    Institute of Scientific and Technical Information of China (English)

    邢娜; 陈敏; 黄奕普; 蔡平河; 邱雨生

    2003-01-01

    Radium-226 (226Ra) activities were measured in the surface water samples collected from the Arctic Ocean and the Bering Sea during the First Chinese National Arctic Research Expedition. The results showed that 226Ra concentrations in the surface water ranged from 0.28 to 1.56 Bq/m3 with an average of 0.76 Bq/m3 in the Arctic Ocean, and from 0.25 to 1.26 Bq/m3 with an average of 0.71 Bq/m3 in the Bering Sea. The values were obviously lower than those from open oceans in middle and low latitudes, indicating that the study area may be partly influenced by sea ice meltwater. In the Bering Sea, 226Ra in the surface water decreased northward, probably as a result of the exchange between the 226Ra-deficientsea ice meltwater and the 226Ra-rich Pacific water. In the Arctic Ocean, 226Ra in the surface water increased northward and eastward. This spatial distributionof 226Ra reflected the variation of the 226Ra-enriched river component in the water mass of the Arctic Ocean. The vertical profiles of 226Ra in the Canadian Basin showed a concentration maximum at 200 m, which could be attributed to the inputs of the Pacific water or/and the bottom shelf water with high 226Ra concentration. This conclusion was consistent with the results from 2H, 18O tracers.

  8. Reassessment of {sup 90}Sr in the Pacific Ocean and the coast off Japan derived from the Fukushima Dai-ichi nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Castrillejo, M.; Masque, P. [Departament de Fisica i Institut de Ciencia i Tecnologia Ambientals, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Casacuberta, N. [Laboratory of Ion Beam Physics, HPK G26, Schafmattstrasse 20, ETH-Zuerich, CH-8093 Zuerich (Switzerland); Breier, C.; Pike, S.; Buesseler, K. [Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, MA02540 (United States)

    2014-07-01

    On 11 March 2011 the Fukushima Dai-ichi nuclear power plant was badly damaged as a consequence of the Tohoku earthquake and subsequent tsunami, causing a large release of artificial radionuclides to the marine environment. Thereinafter, water was used to cool down the reactors, some of which directly entered the ocean via groundwater or leaks from the buildings. Large volumes of contaminated cooling water are generated each day, due to the influx of more than 300 tons of groundwater into the power plants. These contaminated waters are stored on site in large storage tanks, after having been treated using zeolite sorption for the removal of {sup 137}Cs and {sup 134}Cs, and therefore are enriched in {sup 90}Sr compared to {sup 137}Cs and {sup 134}Cs. Leakages from tanks led to {sup 90}Sr concentrations as high as 1000 Bq.L{sup -1} in waters sampled near the leaking tanks. Contaminated water from the trenches and tanks may reach the ocean, leading to further releases of {sup 90}Sr to the Pacific Ocean, and adding to the initial ca. 10{sup 2}-10{sup 3} TBq estimated until June 2011 (Casacuberta et al., 2013). Here we present an overview of the fate and distribution of Fukushima derived {sup 90}Sr in seawater in the Pacific Ocean from June 2011 to September 2013, resulting from samples collected during several research cruises covering transects between North America and Japan, as well as vertical profiles and groundwater near the coast of Fukushima (< 1 km from the power plants). We emphasize our study on the coastal region off Japan, where uptake in to the food web may pose a potential human health hazard due to the accumulation of {sup 90}Sr in seafood. Moreover, changes in the {sup 90}Sr/{sup 137}Cs ratio will be also investigated, as an indicator that might be a useful tool for tracking Fukushima contaminated waters in the Pacific Ocean. Document available in abstract form only. (authors)

  9. Dielectric breakdown during Cs+ sputtering of polyvinyl chloride

    Science.gov (United States)

    Wahoud, F.; Guillot, J.; Audinot, J. N.; Bertrand, P.; Delcorte, A.; Migeon, H. N.

    2014-02-01

    Thin films of insulating polymers are sometimes analyzed by secondary ion mass spectrometry (SIMS) or by X-ray photoelectron spectroscopy (XPS) without the use of an electron gun. In this work, both SIMS and XPS have been used to study the chemical and structural modifications due to the charge effect during Cs+ sputtering of a thin film of polyvinyl chloride (PVC). The kinetic energy distribution study shows that at a small primary fluence ˜1015 Cs+ ions/cm2, the dielectric breakdown voltage of the PVC film is reached, i.e. the minimum voltage that causes a portion of an insulator to become electrically conductive. XPS study indicates that the conducting phase created in the PVC film after energetic Cs+ bombardment consists of graphitized carbon and metallic cesium clusters. After the dielectric breakdown of the film, the positive charge, previously accumulated on the surface, is neutralized through the conductive regions, which are created in the insulating film. During Cs+ sputtering of a PVC film, the chemical structure of the analyzed surface is completely modified and some ionic bonds such as CsC and CsCl are also created.

  10. Performance verification tests of JT-60SA CS model coil

    Energy Technology Data Exchange (ETDEWEB)

    Obana, Tetsuhiro, E-mail: obana.tetsuhiro@LHD.nifs.ac.jp [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Murakami, Haruyuki [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Takahata, Kazuya; Hamaguchi, Shinji; Chikaraishi, Hirotaka; Mito, Toshiyuki; Imagawa, Shinsaku [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Kizu, Kaname; Natsume, Kyohei; Yoshida, Kiyoshi [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)

    2015-11-15

    Highlights: • The performance of the JT-60SA CS model coil was verified. • The CS model coil comprised a quad-pancake wound with a Nb{sub 3}Sn CIC conductor. • The CS model coil met the design requirements. - Abstract: As a final check of the coil manufacturing method of the JT-60 Super Advanced (JT-60SA) central solenoid (CS), we verified the performance of a CS model coil. The model coil comprised a quad-pancake wound with a Nb{sub 3}Sn cable-in-conduit conductor. Measurements of the critical current, joint resistance, pressure drop, and magnetic field were conducted in the verification tests. In the critical-current measurement, the critical current of the model coil coincided with the estimation derived from a strain of −0.62% for the Nb{sub 3}Sn strands. As a result, critical-current degradation caused by the coil manufacturing process was not observed. The results of the performance verification tests indicate that the model coil met the design requirements. Consequently, the manufacturing process of the JT-60SA CS was established.

  11. Syntheses, structures, and optical properties of the indium/germanium selenides Cs{sub 4}In{sub 8}GeSe{sub 16}, CsInSe{sub 2}, and CsInGeSe{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Ward, Matthew D.; Pozzi, Eric A.; Van Duyne, Richard P.; Ibers, James A., E-mail: ibers@chem.northwestern.edu

    2014-04-01

    The three solid-state indium/germanium selenides Cs{sub 4}In{sub 8}GeSe{sub 16}, CsInSe{sub 2}, and CsInGeSe{sub 4} have been synthesized at 1173 K. The structure of Cs{sub 4}In{sub 8}GeSe{sub 16} is a three-dimensional framework whereas those of CsInSe{sub 2} and CsInGeSe{sub 4} comprise sheets separated by Cs cations. Both Cs{sub 4}In{sub 8}GeSe{sub 16} and CsInGeSe{sub 4} display In/Ge disorder. From optical absorption measurements these compounds have band gaps of 2.20 and 2.32 eV, respectively. All three compounds are charge balanced. - Graphical abstract: Structure of Cs{sub 4}In{sub 8}GeSe{sub 16}. - Highlights: • The solid-state In/Ge selenides Cs{sub 4}In{sub 8}GeSe{sub 16}, CsInSe{sub 2}, and CsInGeSe{sub 4} have been synthesized. • Both Cs{sub 4}In{sub 8}GeSe{sub 16} and CsInGeSe{sub 4} display In/Ge disorder. • Cs{sub 4}In{sub 8}GeSe{sub 16} and CsInGeSe{sub 4} have band gaps of 2.20 eV and 2.32 eV, respectively.

  12. Effect of new and conventional technological processes on the terroir marker 87Sr/86Sr

    Directory of Open Access Journals (Sweden)

    Catarino Sofia

    2016-01-01

    Full Text Available Aiming to use the strontium isotopic ratio 87Sr/86Sr for traceability and authentication of wine, it is crucial to understand the impacts of anthropogenic factor and technological processes on this parameter. In this study the effect of two technologies: nanofiltration (NF, applied for wine dealcoholisation (1, and ageing with oak wood staves (2, on 87Sr/86Sr ratio of wines from Portuguese Designations of Origin (DO, was assessed. Control wines, NF processed wines and wooden aged wines were evaluated for chemical composition, multi-elemental composition and 87Sr/86Sr ratio by Q-ICP-MS. Regarding NF experiments, high rejections to mineral elements, including heavy metals, were observed. Bearing in mind the several roles played by these elements in wine, this knowledge is of strategic importance in order to guarantee that NF process does not adversely affect product quality. Concerning wood ageing experiment, results indicate the influence of this technological process on metal physical-chemical stability. In the experimental conditions of this study, no significant effect of NF process and wood ageing on 87Sr/86Sr ratio was observed, suggesting that the application of these technologies in wine production is not a limitative factor for the use of 87Sr/86Sr ratio as a geographical origin marker.

  13. Maxdose-SR and popdose-SR routine release atmospheric dose models used at SRS

    Energy Technology Data Exchange (ETDEWEB)

    Jannik, G. T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Trimor, P. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-07-28

    MAXDOSE-SR and POPDOSE-SR are used to calculate dose to the offsite Reference Person and to the surrounding Savannah River Site (SRS) population respectively following routine releases of atmospheric radioactivity. These models are currently accessed through the Dose Model Version 2014 graphical user interface (GUI). MAXDOSE-SR and POPDOSE-SR are personal computer (PC) versions of MAXIGASP and POPGASP, which both resided on the SRS IBM Mainframe. These two codes follow U.S. Nuclear Regulatory Commission (USNRC) Regulatory Guides 1.109 and 1.111 (1977a, 1977b). The basis for MAXDOSE-SR and POPDOSE-SR are USNRC developed codes XOQDOQ (Sagendorf et. al 1982) and GASPAR (Eckerman et. al 1980). Both of these codes have previously been verified for use at SRS (Simpkins 1999 and 2000). The revisions incorporated into MAXDOSE-SR and POPDOSE-SR Version 2014 (hereafter referred to as MAXDOSE-SR and POPDOSE-SR unless otherwise noted) were made per Computer Program Modification Tracker (CPMT) number Q-CMT-A-00016 (Appendix D). Version 2014 was verified for use at SRS in Dixon (2014).

  14. The Paran\\'a Ra'anga expedition

    CERN Document Server

    Gangui, Alejandro; Vena, Pablo

    2013-01-01

    Paran\\'a Ra'anga (the image of Paran\\'a, in Guaran\\'i) is the name of a cultural and scientific expedition that traveled the rivers: R\\'io de la Plata, Paran\\'a and Paraguay, from Buenos Aires to Asunci\\'on, during March 2010. The project brought together some forty scientists and artists from three countries in a slow and enriching cruise, putting in active contact actors from different backgrounds and disciplines -which usually run separately- in the framework of an unusual space-time experience. The project recovers the historical tradition of the trip as an instrument of knowledge and collaboration between the arts and sciences, necessary to build new ways of seeing and understanding the river and its banks. This article reports on the motivations of this project and its projection.

  15. Loe-ära-loe! Eesti lastekirjandus 2007 / Jaanika Palm

    Index Scriptorium Estoniae

    Palm, Jaanika

    2008-01-01

    Hainsalu, Lehte. Rõõmuratas (TEA Kirjastus) ; Vilep, Heiki. Katus sõidab (Vilep & Vallik) ; Vaiksoo, Jaanus. Onu Heino eksis ära (Koolibri) ; Vallik, Aidi. Tirtsti ja turtsti (TEA Kirjastus) ; Trull, Ilmar. Järvevaht ja joogivesi (Eesti Ekspressi Kirjastus) ; Kassel, Riina. Kalliralli (Ilo) ; Kumberg, Krista. Autopõnn Anto lemmiktoit (Koolibri) ; Ojar, Triinu. Suur must koer = Suur must pini (Päike ja Pilv) ; Pervik, Aino. Suleline, Puhuja ja must Munk (Tänapäev) ; Tomusk, Ilmar. Tere, Volli! (Tänapäev) ; Ausman, Piia. Tähtsad asjad (Haus Galerii) ; Ulman, Mihkel. Võlur taskust (Elmatar) ; Tangsoo, Jaan. Kotermann Juko imeline reis läbi Eestimaa (Varrak) ; Made, Reet. Tuhin tiibades (Koolibri) ; Vallik, Aidi. Mis sinuga juhtus, Ann? (Tänapäev)

  16. Search for psipp\\ra\\rho\\pi at BESII

    CERN Document Server

    Ablikim, M

    2005-01-01

    Non-$D\\bar{D}$ decay $\\psppto \\rhopi$ is searched for using a data sample of $(17.3\\pm 0.5)~pb^{-1}$ taken at the center-of-mass energy of 3.773 GeV by the BESII detector at the BEPC. No $\\rhopi$ signal is observed, and the upper limit of the cross section is measured to be $\\sigma(\\EETO \\rhopi)<6.0~pb$ at 90% C. L. Considering the interference between the continuum amplitude and the $\\pspp$ resonance amplitude, the branching fraction of $\\pspp$ decays to $\\rho\\pi$ is determined to be $\\BR(\\pspp\\ra\\rho\\pi)\\in(6.0\\times10^{-6},~2.4\\times10^{-3})$ at 90% C. L. This is in agreement with the prediction of the $S$- and $D$-wave mixing scheme of the charmonium states for solving the ``$\\rhopi$ puzzle'' between $\\jpsi$ and $\\psp$ decays.

  17. Loe-ära-loe! Eesti lastekirjandus 2007 / Jaanika Palm

    Index Scriptorium Estoniae

    Palm, Jaanika

    2008-01-01

    Hainsalu, Lehte. Rõõmuratas (TEA Kirjastus) ; Vilep, Heiki. Katus sõidab (Vilep & Vallik) ; Vaiksoo, Jaanus. Onu Heino eksis ära (Koolibri) ; Vallik, Aidi. Tirtsti ja turtsti (TEA Kirjastus) ; Trull, Ilmar. Järvevaht ja joogivesi (Eesti Ekspressi Kirjastus) ; Kassel, Riina. Kalliralli (Ilo) ; Kumberg, Krista. Autopõnn Anto lemmiktoit (Koolibri) ; Ojar, Triinu. Suur must koer = Suur must pini (Päike ja Pilv) ; Pervik, Aino. Suleline, Puhuja ja must Munk (Tänapäev) ; Tomusk, Ilmar. Tere, Volli! (Tänapäev) ; Ausman, Piia. Tähtsad asjad (Haus Galerii) ; Ulman, Mihkel. Võlur taskust (Elmatar) ; Tangsoo, Jaan. Kotermann Juko imeline reis läbi Eestimaa (Varrak) ; Made, Reet. Tuhin tiibades (Koolibri) ; Vallik, Aidi. Mis sinuga juhtus, Ann? (Tänapäev)

  18. An implanted $^{228}$Ra source for response characterization of bolometers

    CERN Multimedia

    TeO$_{2}$ crystals are used as bolometers in experiments searching for Double $\\beta$ Decay without emission of neutrinos. One of the most important issues in this extremely delicate kind of experiments is the discrimination of the background from the real signal. A deep knowledge of the bolometric response to $\\alpha$-particles is therefore needed to recognize and discard them, since it has been proven that $\\alpha$ surface contamination could be a major contribution in our background budget. We would like to use ISOLDE’s capability of implanting $^{228}$Ra to make a long-lived source feeding several monochromatic $\\alpha$- and recoiling nuclei, with little or no $\\alpha$-peak broadening due to the source itself, for tests of our detectors in Milano and Gran Sasso INFN National Lab.

  19. Safety and immunogenicity of the malaria candidate vaccines FP9 CS and MVA CS in adult Gambian men.

    Science.gov (United States)

    Imoukhuede, E B; Berthoud, T; Milligan, P; Bojang, K; Ismaili, J; Keating, S; Nwakanma, D; Keita, S; Njie, F; Sowe, M; Todryk, S; Laidlaw, S M; Skinner, M A; Lang, T; Gilbert, S; Greenwood, B M; Hill, A V S

    2006-10-30

    We assessed the safety and immunogenicity of prime-boost vectors encoding the Plasmodium falciparum circumsporozoite (CS) protein expressed either in the attenuated fowl-pox virus (FP9) or modified vaccinia virus Ankara (MVA). Thirty-two adult Gambians in groups of four to eight received one, two or three doses of FP9 CS and/or MVA CS. No serious adverse event was observed following vaccination. The most immunogenic regimen was two doses of FP9 followed by a single dose of MVA 4 weeks later (an average of 1000 IFN-gamma spot forming units/million PBMCs). This level of effector T-cell responses appears higher than that seen in previously reported studies of CS-based candidate malaria vaccines.

  20. Vertical distribution of Th-isotope ratios, {sup 210}Pb, {sup 226}Ra and {sup 137}Cs in sediment cores from an estuary affected by anthropogenic releases

    Energy Technology Data Exchange (ETDEWEB)

    San Miguel, E.G.; Bolivar, J.P. [Dpto Fisica Aplicada, E.P.S. La Rabida, Ctra Palos S/N, Huelva 21819 (Spain); Garcia-Tenorio, R. [Dpto Fisica Aplicada, E.T.S. Arquitectura, Avda, Reina Mercedes, 2, Sevilla 41012 (Spain)

    2004-01-05

    In an estuary system highly polluted by mining and industrial activities, the sections of sediment cores affected by anthropogenic inputs of U-series radionuclides (due to fertilizer plants releases) were determined through the vertical profiles of Th-isotopic ratio ({sup 230}Th/{sup 232}Th). Also, when possible, a modified version of the {sup 210}Pb dating method was applied in the uncontaminated sections of these cores. Using the information provided by the Th-isotopic ratio and {sup 210}Pb methods, we were able to establish confident chronologies, covering the last century, in several of the analysed sediment cores. These chronologies will be used in forthcoming research to study the time evolution of pollutant concentrations in the estuary. Additionally, and based on the established chronologies, we have found that sedimentation rates have drastically increased in some zones of the estuary since the commencement of several industrial activities in the surrounding environment and since the construction of two dikes in the area.

  1. Raíces griegas: tan lejanas y tan cercanas

    Directory of Open Access Journals (Sweden)

    Ana María Gispert-Sauch Colls

    2011-05-01

    Full Text Available Isidoro de Sevilla en su obra maestra Etimologías, supo unir el “origen”, o sea, de dónde viene un vocablo y la “etimología”, que sería el “por qué” se aplica este vocablo a una realidad concreta. Hizo, pues, una distinción entre etimologías ex causa (según lo que es y etimologías ex origine (según de dónde viene. Y, como de lo que se trataba era decaptar el valor esencial de una palabra, dice Isidoro, “cuando se ha visto de dónde viene un nombre, se comprende más rápidamente su valor, porque el estudio de las realidades es más fácil una vez conocida la etimología” (Etimologías, I, 19, 2. Siguiendo en parte esta orientación, presentamos algunas raíces de verbos griegos, lejanos en referencia al tiempo de su origen, pero presentes en nuestro tiempo a través de sus derivaciones. Y, sobre todo persistentes, porque nos transmiten la esencia de significado, ladensidad semántica, a la que he aludido en varias ocasiones1.De esta forma, el hoy de muchas de nuestras palabras está impregnado de este pasado clásico que nos invita a recuperar permanentemente su esencia. No en vano y refiriéndonos a Sócrates, podríamos decir que la etimología tiene una función “mayéutica”, la de sacar a la luz el núcleofecundo de las palabras. Veamos algunas de dichas raíces.

  2. Estrutura populacional da raça Nelore Mocho

    Directory of Open Access Journals (Sweden)

    Faria F.J.C.

    2002-01-01

    Full Text Available Descreveu-se a estrutura populacional da raça Nelore Mocho utilizando dados do registro genealógico de animais nascidos entre 1969 e 1998. O banco de dados foi separado em quatro períodos de 1979-1983, 1984-1988, 1989-1993 e 1994-1998. Calcularam-se as estatísticas descritivas do número de criadores, de reprodutores e de reprodutrizes. A endogamia total aumentou de 0,55% para 0,98%, a esperada sob acasalamento ao acaso aumentou de 0,11% para 0,56% e a endogamia devido à subdivisão populacional permaneceu constante, ao redor de 0,45%, indicando que a subdivisão genética da raça Nelore Mocho é próxima a zero e praticamente inexistente. O tamanho efetivo populacional foi estimado pelo coeficiente total de endogamia e permaneceu ao redor de 120. A inclusão de animais no livro genealógico aumentou de 4.630 para 13.907, entretanto, esta ação não foi suficiente para incrementar o tamanho efetivo. Baseado na probabilidade de origem do gene foram calculados o número efetivo de fundadores, de ancestrais e de genomas remanescentes. Esses parâmetros decresceram ao longo do período, atingindo valores de 144, 98 e 64. Todas as estimativas foram análogas na descrição da estrutura genética populacional e devem ser consideradas no futuro para o desenvolvimento de programas de seleção.

  3. 230Th, 226Ra and 222Rn in abyssal sediments

    Science.gov (United States)

    Kadko, David

    1980-09-01

    A model that predicts the flux of 222Rn out of deep-sea sediment is presented. The radon is ultimately generated by 230Th which is stripped from the overlying water into the sediment. Data from many authors are compared with the model predictions. It is shown that the continental contribution of ionium is not significant, and that at low sedimentation rates, biological mixing and erosional processes strongly affect the surface concentration of the ionium. Two cores from areas of slow sediment accumulation, one from a manganese nodule region of the central Pacific and one from the Rio Grande Rise in the Atlantic were analyzed at closely spaced intervals for 230Th, 226Ra, and 210Pb. The Pacific core displayed evidence of biological mixing down to 12 cm and had a sedimentation rate of only 0.04 cm/kyr. The Atlantic core seemed to be mixed to 8 cm and had a sedimentation rate of 0.07 cm/kyr. Both cores had less total excess 230Th than predicted. Radium sediment profiles are generated from the 230Th model. Adsorbed, dissolved, and solid-phase radium is considered. According to the model, diffusional losses of radium are especially important at low sedimentation rates. Any particulate, or excess radium input is ignored in this model. The model fits the two analyzed cores if the fraction of total radium available for adsorption-desorption is about 0.5-0.7, and if K, the distribution coefficient, is about 1000. Finally, the flux of radon out of the sediments is derived from the model-generated radium profiles. It is shown that the resulting standing crop of 222Rn in the overlying water may be considered as an added constraint in budgeting 230Th and 226Ra in deep-sea sediments.

  4. Processing of Radioactive Waste Solution with Zeolites (I) : Thermal-Transformations of Na, Cs and Sr Forms of Zeolites

    OpenAIRE

    Mimura, Hitoshi; KANNO, Takuji

    1980-01-01

    Thermal-transformations of several kinds of zeolites have been studied by means of differential thermal analysis (DTA), thermo-gravimetric analysis (TGA) and X-ray powder diffraction. Some synthetic zeolites (A, X, Y, mordenite), natural mordenite and clinoptilolite were used. Sodium forms of A and X zeolites recrystallized above 1000℃ to nepheline (NaAlSiO_4) , whereas the structure of zeolite Y, synthetic and natural mordenites, and clinoptilolite collapsed above around 900℃ and did not rec...

  5. Development of a liquid scintillation method for in vitro determination of {sup 226}Ra and {sup 228} Ra in bioassay samples

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Paulo Cesar P.; Sousa, Wanderson O.; Juliao, Ligia M.Q.C.; Dantas, Bernardo M., E-mail: pcesar@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2011-07-01

    Radium isotopes are dispersed in the environment according to their physicochemical characteristics. The intake of {sup 226}Ra and {sup 228}Ra in humans can occur by inhalation and ingestion and the risk of internal exposure are related to their long half-lives, characteristics of the emission and biokinetics of the isotopes in the human body. The goal of this work is to develop a methodology for the analysis of {sup 226}Ra and {sup 228}Ra in excreta samples (urine and feces), using liquid scintillation technique. Excreta samples were provided by non-exposed humans for the purpose of standardizing the methodology and the establishment of a background level of radium excretion. Radium isotopes were concentrated and separated from the constituents of the sample by co-precipitation with barium sulphate. The precipitate of Ba(Ra)SO{sub 4} was filtrated and weighted for the determination of the chemical yield. The filter containing the precipitate was transferred to a scintillation vial. In the scintillation vial, 8 mL of water, 8 mL of Instagel XF and 4 mL of UltimaGold were added, forming a gel suspension, after stirring the solution. The {sup 226}Ra and {sup 228}Ra activities were determined 21 days after the precipitation of samples. The samples were counted in a liquid scintillation spectrometer. The technique presented adequate sensitivity and reproducibility for the analysis of urine and feces. The activities of {sup 226}Ra and {sup 228}Ra in excreta samples provide useful information for the identification of the main route of intake and for the assessment of the internal exposure of occupationally exposed workers and inhabitants of high background areas. (author)

  6. Sm-doped CsBr crystal as a new radio-photoluminescence (RPL) material

    Institute of Scientific and Technical Information of China (English)

    Go Okada; Yutaka Fujimoto; Hironori Tanaka; Safa Kasap; Takayuki Yanagida

    2016-01-01

    Radio-photoluminescence (RPL) is a phenomenon seen in luminescent materials in which the appearance of new photolu-minescence (PL) emission is induced by an incident ionizing radiation such as X-rays;and the signal is stable even after the irradia-tion and during the PL measurement. Since the induced PL intensity is proportional to the irradiation dose, the RPL can be used in ra-diation measurements. The distinct advantage of RPL over the conventional thermally-or photo-stimulated luminescence (abbrevi-ated as TSL or PSL) dosimeters is the stability of response signal. With an RPL detector, it allows us to readout the signal multiple time without signal fading. In this work, we discovered that CsBr:Sm showed an RPL phenomenon by X-ray irradiation, and we characterized this new material as an RPL detector. While the sample showed PL emissions mainly in the visible range, after an X-ray irradiation additional emissions could be observed in the red to near-infrared range around 650–850 nm and 900–1000 nm and longer. The RPL response was fairly stable overall, but very interestingly the 650–850 nm signal slightly increased while the 900–1000 nm decreased during PL readout. The dynamic range was confirmed over 1–104 mGy with linear response.

  7. Charged-particle detection efficiencies of close-packed CsI arrays

    Science.gov (United States)

    Morfouace, P.; Lynch, W. G.; Tsang, M. B.

    2017-03-01

    Detector efficiency determination is essential to correct the measured yields and extract reliable cross sections of particles emitted in nuclear reactions. We investigate the efficiencies for measuring the full energies of light charged particle in arrays of CsI crystals employed in particle detection arrays such as HiRA, LASSA and MUST2. We perform these simulations with a GEANT4 Monte Carlo transport code implemented in the NPTool framework. Both Coulomb multiple scattering and nuclear reactions within the crystal can significantly reduce the efficiency of detecting the full energy of high energy particles. The calculated efficiencies decrease exponentially as a function of the range of the particle and are quite similar for both the hydrogen (p , d , t) and helium (3He, α) isotopes. The use of a close-packed array introduces significant position dependent efficiency losses at the interior boundaries between crystals that need to be considered in the design of an array and in the efficiency corrections of measured energy spectra.

  8. Examination of SR101 shipping packages

    Energy Technology Data Exchange (ETDEWEB)

    Daugherty, W. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-03-01

    Four SR101 shipping packages were removed from service and provided for disassembly and examination of the internal fiberboard assemblies. These packages were 20 years old, and had experienced varying levels of degradation. Two of the packages were successfully disassembled and fiberboard samples were removed from these packages and tested. Mechanical and thermal property values are generally comparable to or higher than baseline values measured on fiberboard from 9975 packages, which differs primarily in the specified density range. While baseline data for the SR101 material is not available, this comparison with 9975 material suggests that the material properties of the SR101 fiberboard have not significantly degraded.

  9. Evaluation of Lama5 as a candidate for the mouse ragged (Ra) mutation

    DEFF Research Database (Denmark)

    Durkin, M E; Albrechtsen, R; Chambers, D M;

    1998-01-01

    The laminin alpha5 chain is a component of the basement membranes of many developing and adult tissues. The mouse laminin alpha5 chain gene (Lama5) has been mapped close to the locus of the semidominant ragged (Ra) mutation on distal chromosome 2. The cause of the Ra mutation, which is usually...... lethal in the homozygous state, has not been determined. We have investigated whether a defect in Lama5 is responsible for the ragged mutation, using the RaJ strain. No differences in the level of the laminin alpha5 chain transcript were found in placental RNA from homozygous RaJ mutant embryos compared...... to normal littermates. Antiserum raised against a recombinant laminin alpha5 chain polypeptide stained the basement membranes of both normal and homozygous mutant embryos to a similar extent. More precise mapping of Lama5 on an interspecific Ra backcross indicated that Lama5 is proximal to the Ra locus...

  10. EXPRESSION OF IL-13Ra2 GENE IN HUMAN BRAIN TUMORS

    Institute of Scientific and Technical Information of China (English)

    WU An-hua; TIE Xin-xin; WANG Yun-jie; YANG Guo-rui

    2005-01-01

    Objective: To investigate the expression of IL-13Ra2 gene in brain tumors. Methods: Seventy-nine human brain tumors were obtained from the department of Neurosurgery of China Medical University. Human IL-13Ra2 expression was evaluated by reverse transcriptase polymerase chain reaction and immunohistochemical analysis. Results: IL-13Ra2 gene was highly expressed in glioblastoma, medulloblastoma, malignant meningioma and benign meningioma. Conclusion:Human IL-13Ra2 gene is expressed in brain tumors in addition to gliomas, and our result indicates that the IL-13Ra2 gene promoter based gene therapy method can be used to treat brain tumors in addition to gliomas. Further studies involving larger numbers of samples are necessary to fully understand the expression profile of IL-13Ra2 gene in the brain tumors.

  11. Assessment of the radium-barium co-precipitation and its potential influence on the solubility of Ra in the near-field

    Energy Technology Data Exchange (ETDEWEB)

    Grandia, Fidel; Merino, Joan; Bruno, Jordi (Amphos XXI Consulting S.L., Barcelona (Spain))

    2008-08-15

    Radium 226 is one of the main contributors to radiological dose in some of the scenarios contemplated in the recent SR Can safety assessment. The relative contribution of the 226Ra dose is clearly dependent on the source term value for this radionuclide, which is directly connected to its solubility behaviour. Most of the source term calculations performed for this radionuclide pessimistically assume that its solubility is controlled by the individual solubility of RaSO{sub 4}(s), the most insoluble phase under near field conditions, while the abundant information from early radiochemical research, natural system studies and anthropogenic systems would indicate that Ra(II) is mainly associated to BaSO{sub 4}(s) precipitation. In this work we have investigated the extensive literature concerning the mechanisms and processes controlling the co-precipitation/solid solution formation behaviour of the Ra(II)/Ba(II) sulphate system. We have also established the necessary thermodynamic moles to model the solubility behaviour in the vicinity of the spent fuel system. Calculations using an ATM-104 fuel at 40 MWd/kg U show that barium and radium inventories per canister progressively grow with time after deposition, most of the barium is produced in the initial 500 years. In the unlikely event of a contact of sulphate-containing groundwaters with the fuel, Ba(II) will precipitate as BaSO{sub 4}(s). The production of 226Ra reaches its peak some 300,000 years after deposition. This substantial time gap indicates that most of the BaSO{sub 4}(s) will be present when and if radium is released from the fuel, even if some Ra(II) and Ba(II) will be released contemporaneously. Two potential scenarios have been addressed from the mechanistic point of view. In the event of a simultaneous release of Ra with Ba, the former will be readily incorporated into the precipitating BaSO{sub 4} to build a Ra Ba sulphate solid solution. All the existing evidence indicates, that in this case, the

  12. Assessment of the radium-barium co-precipitation and its potential influence on the solubility of Ra in the near-field

    Energy Technology Data Exchange (ETDEWEB)

    Grandia, Fidel; Merino, Joan; Bruno, Jordi (Amphos XXI Consulting S.L., Barcelona (Spain))

    2008-08-15

    Radium 226 is one of the main contributors to radiological dose in some of the scenarios contemplated in the recent SR Can safety assessment. The relative contribution of the 226Ra dose is clearly dependent on the source term value for this radionuclide, which is directly connected to its solubility behaviour. Most of the source term calculations performed for this radionuclide pessimistically assume that its solubility is controlled by the individual solubility of RaSO{sub 4}(s), the most insoluble phase under near field conditions, while the abundant information from early radiochemical research, natural system studies and anthropogenic systems would indicate that Ra(II) is mainly associated to BaSO{sub 4}(s) precipitation. In this work we have investigated the extensive literature concerning the mechanisms and processes controlling the co-precipitation/solid solution formation behaviour of the Ra(II)/Ba(II) sulphate system. We have also established the necessary thermodynamic moles to model the solubility behaviour in the vicinity of the spent fuel system. Calculations using an ATM-104 fuel at 40 MWd/kg U show that barium and radium inventories per canister progressively grow with time after deposition, most of the barium is produced in the initial 500 years. In the unlikely event of a contact of sulphate-containing groundwaters with the fuel, Ba(II) will precipitate as BaSO{sub 4}(s). The production of 226Ra reaches its peak some 300,000 years after deposition. This substantial time gap indicates that most of the BaSO{sub 4}(s) will be present when and if radium is released from the fuel, even if some Ra(II) and Ba(II) will be released contemporaneously. Two potential scenarios have been addressed from the mechanistic point of view. In the event of a simultaneous release of Ra with Ba, the former will be readily incorporated into the precipitating BaSO{sub 4} to build a Ra Ba sulphate solid solution. All the existing evidence indicates, that in this case, the

  13. Correlations between potassium, rubidium and cesium ({sup 133}Cs and {sup 137}Cs) in sporocarps of Suillus variegatus in a Swedish boreal forest

    Energy Technology Data Exchange (ETDEWEB)

    Vinichuk, M., E-mail: Mykhailo.Vinichuk@slu.s [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, SE-750 07 Uppsala (Sweden); Department of Ecology, Zhytomyr State Technological University, 103 Cherniakhovsky Str., 10005 Zhytomyr (Ukraine); Rosen, K.; Johanson, K.J. [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, SE-750 07 Uppsala (Sweden); Dahlberg, A. [Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, P.O. Box 7026, 750 07 Uppsala (Sweden)

    2011-04-15

    An analysis of sporocarps of ectomycorrhizal fungi Suillus variegatus assessed whether cesium ({sup 133}Cs and {sup 137}Cs) uptake was correlated with potassium (K) or rubidium (Rb) uptake. The question was whether intraspecific correlations of Rb, K and {sup 133}Cs mass concentrations with {sup 137}Cs activity concentrations in sporocarps were higher within, rather than among, different fungal species, and if genotypic origin of sporocarps within a population affected uptake and correlation. Sporocarps (n = 51) from a Swedish forest population affected by the fallout after the Chernobyl accident were studied. The concentrations were 31.9 {+-} 6.79 g kg{sup -1} for K (mean {+-} SD, dwt), 0.40 {+-} 0.09 g kg{sup -1} for Rb, 8.7 {+-} 4.36 mg kg{sup -1} for {sup 133}Cs and 63.7 {+-} 24.2 kBq kg{sup -1} for {sup 137}Cs. The mass concentrations of {sup 133}Cs correlated with {sup 137}Cs activity concentrations (r = 0.61). There was correlation between both {sup 133}Cs concentrations (r = 0.75) and {sup 137}Cs activity concentrations (r = 0.44) and Rb, but the {sup 137}Cs/{sup 133}Cs isotopic ratio negatively correlated with Rb concentration. Concentrations of K and Rb were weakly correlated (r = 0.51). The {sup 133}Cs mass concentrations, {sup 137}Cs activity concentrations and {sup 137}Cs/{sup 133}Cs isotopic ratios did not correlate with K concentrations. No differences between, within or, among genotypes in S. variegatus were found. This suggested the relationships between K, Rb, {sup 133}Cs and {sup 137}Cs in sporocarps of S. variegatus is similar to other fungal species. - Highlights: {yields} We studied uptake of Cs ({sup 133}Cs and {sup 137}Cs), K and Rb by Suillus variegates sporocarps. {yields} Genotypic origin of fungus did not affect uptake of studied elements (isotopes). {yields} Genotypic origin did not affect correlation between Cs ({sup 133}Cs and {sup 137}Cs), K and Rb.

  14. Geochemistry of trace elements and Sr- Nd isotopes of foraminifera shell from the Okinawa Trough

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Trace elemental associations and Sr - Nd isotopic compositions are of important to recognition of biogenic material from mixed marine sediments. The foraminifera shell from the Okinawa Trough strongly enrichesSr, P, Mn andBa, enriches Li, U, Th, Sc, Co, Cu, Pb, Zn, Cr, Rb, Y, Sb and light rare earth elements, slightly enriches V, Ga, Zr, Nb, Cd and middle rare earth elements,is short of Mo, In, Sn, Cs, Hf, Ta, W, Ti, Bi and heavy rare earth elements. The mechanism of elemental enrichment in forminifera is the concentrations of trace elements in sea water and selective absorption of trace elements during foraminifera living, as well as the geochemical affinity between major elements and trace elements. The REE (rare earth elements) partition pattern of foraminifera shell of the Okinawa Trough shows enrichment of middle rare earth elements with slightly negative Ce anomaly,which are different from those of foraminifera of the Pacific Ocean. The Sr, Nd isotopic ratios of the Okinawa Trough foraminifera are 0.709 769 and 0.512 162, respectively, which are different not only from those of oceanic water, but also from those of river water of China's Mainland, the former is slightly higher than those of oceanic water, but much lower than those of river water; the latter is slightly lower than those of oceanic water, but higher than those of river water, demonstrating that the Okinawa Trough sea water has been influenced by river water of China's Mainland.

  15. Sr fluxes and isotopic compositions of the eleven rivers originating from the Qinghai-Tibet Plateau and their contributions to 87Sr/86Sr evolution of seawater

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    To evaluate influence of chemical weathering of the Qinghai-Tibet Plateau (QTP) on seawater 87Sr/86Sr variation, river water and sediment samples were collected, and their Sr concentrations and isotopic compositions analyzed, from the seven large rivers that originated from the QTP. By combining these with the data of the Ganges, Brahmaputra, Indus and Irrawaddy originated in the southern QTP, the total Sr flux of the eleven rivers reaches 3.47×109 mol·a-1, which accounts for 10.2% of the total Sr flux transported by the global rivers. The weighted mean 87Sr/86Sr is 0.71694, higher than the average value of the global rivers. The 87Srex (87Sr flux in excess of the seawater 87Sr/86Sr ratio) of the Chinese seven rivers is 1.55×106 mol·a-1, only accounting for about 6% of the value of the eleven rivers originated from QTP, and the Ganges-Brahmaputra system accounts for 86%. We assume that the QTP rivers have no strontium contributions to the oceans before ~40 Ma and the Sr fluxes of the global rivers, except the QTP eleven rivers, are constant, then a maximum linear increase in Sr fluxes of the QTP rivers from zero to the modern value in response to tectonic uplift can explain ~69% increase of seawater 87Sr/86Sr over the past ~40 Ma and the remainder of 31% is perhaps provided from other factors.

  16. Reference levels of natural radioactivity and (137)Cs in and around the surface soils of Kestanbol pluton in Ezine region of Çanakkale province, Turkey.

    Science.gov (United States)

    Öztürk, Buket Canbaz; Çam, N Füsun; Yaprak, Günseli

    2013-01-01

    The aim of the study was to conduct a systematic investigation on the natural gamma emitting radionuclides ((226)Ra, (232)Th and (40)K) as well as (137)Cs in the surface soils from Kestanbol/Ezine plutonic area in Çanakkale province as part of the environmental monitoring program on radiologic impact of the granitoid areas in Western Anatolia. The activity measurements of the gamma emitters in the surface soil samples collected from 52 sites distributed all over the region has been carried out, by means of HPGe gamma-ray spectrometry system. The activity concentrations of the relevant radionuclides in the soil samples appeared in the ranges as follows: (226)Ra was 20-521 Bq kg(-1); (232)Th, 11-499 Bq kg(-1)and; (40)K, 126-3181 Bq kg(-1), yet the (137)Cs was much lower than 20 Bq kg(-1)at most. Furthermore, based on the available data, the radiation hazard parameters associated with the surveyed soils were calculated. The present data also allowed evaluation of some correlations that may exist in the investigated natural radionuclides of the soil samples from the plutonic area in Çanakkale province. It is concluded from the above that the concerned region did not lead to any significant radiological exposure to the environment.

  17. Distribution of naturally occurring radioactivity and ¹³⁷Cs in the marine sediment of Farasan Island, southern Red Sea, Saudi Arabia.

    Science.gov (United States)

    Al-Zahrany, A A; Farouk, M A; Al-Yousef, A A

    2012-11-01

    The present work is a part of a project dedicated to measure the marine radioactivity near the Saudi Arabian coasts of the Red Sea and Arabian Gulf for establishing a marine radioactivity database, which includes necessary information on the background levels of both naturally occurring and man-made radionuclides in the marine environment. Farasan Islands is a group of 84 islands (archipelago), under the administration of the Kingdom of Saudi Arabia, in the Red Sea with its main island of Farasan, which is 50 km off the coast of Jazan City. The levels of natural radioactivity of (238)U, (235)U, (226)Ra, (232)Th and (40)K and man-made radionuclides such as (137)Cs in the grab sediment and water samples around Farasan Island have been measured using gamma-ray spectroscopy. The average activity concentrations of (238)U, (235)U, (226)Ra, (232)Th, (40)K and (137)Cs in the sediment samples were found to be 35.46, 1.75, 3.31, 0.92, 34.34 and 0.14 Bq kg(-1), respectively.

  18. Accurate absolute measurement of trapped Cs atoms in a MOT

    Energy Technology Data Exchange (ETDEWEB)

    Talavera O, M.; Lopez R, M.; Carlos L, E. de [Division de Tiempo y Frecuencia, Centro Nacional de Metrologia, CENAM, km 4.5 Carretera a los Cues, El Marques, 76241 Queretaro (Mexico); Jimenez S, S. [Centro de Investigacion y Estudios Avanzados del lPN, Unidad Queretaro, Libramiento Norponiente No. 2000, Fracc. Real de Juriquilla, 76230 Queretaro (Mexico)

    2007-07-01

    A Cs-133 Magneto-Optical Trap (MOT) has been developed at the Time and Frequency Division of the Centro Nacional de Metrologia, CENAM, in Mexico. This MOT is part of a primary frequency standard based on ultra-cold Cs atoms, called CsF-1 clock, under development at CENAM. In this Cs MOT, we use the standard configuration ({sigma}{sup +} - {sigma}{sup -}) 4-horizontal 2-vertical laser beams 1.9 cm in diameter, with 5 mW each. We use a 852 nm, 5 mW, DBR laser as a master laser which is stabilized by saturation spectroscopy. Emission linewidth of the master laser is l MHz. In order to amplify the light of the master laser, a 50 mW, 852 nm AlGaAs laser is used as slave laser. This slave laser is stabilized by light injection technique. A 12 MHz red shift of the light is performed by two double passes through two Acusto-Optic Modulators (AOMs). The optical part of the CENAMs MOT is very robust against mechanical vibration, acoustic noise and temperature changes in our laboratory, because none of our diode lasers use an extended cavity to reduce the linewidth. In this paper, we report results of our MOT characterization as a function of several operation parameters such as the intensity of laser beams, the laser beam diameter, the red shift of light, and the gradient of the magnetic field. We also report accurate absolute measurement of the number of Cs atoms trapped in our Cs MOT. We found up to 6 x 10{sup 7} Cs atoms trapped in our MOT measured with an uncertainty no greater than 6.4%. (Author)

  19. Cell therapy centered on IL-1Ra is neuroprotective in experimental stroke

    DEFF Research Database (Denmark)

    Clausen, Bettina Hjelm; Lambertsen, Kate Lykke; Dagnæs-Hansen, Frederik;

    2016-01-01

    Cell-based therapies are emerging as new promising treatments in stroke. However, their functional mechanism and therapeutic potential during early infarct maturation has so far received little attention. Here, we asked if cell-based delivery of the interleukin-1 receptor antagonist (IL-1Ra...... production of IL-1Ra and IL-1α/β identifies microglia, not infiltrating leukocytes, as the major sources of IL-1Ra after experimental stroke, and shows IL-1Ra and IL-1β to be produced by segregated subsets of microglia with a small proportion of these cells co-expressing IL-1α. Reconstitution of whole body...

  20. First Measurement of the Atomic Electric Dipole Moment of (225)Ra.

    Science.gov (United States)

    Parker, R H; Dietrich, M R; Kalita, M R; Lemke, N D; Bailey, K G; Bishof, M; Greene, J P; Holt, R J; Korsch, W; Lu, Z-T; Mueller, P; O'Connor, T P; Singh, J T

    2015-06-12

    The radioactive radium-225 ((225)Ra) atom is a favorable case to search for a permanent electric dipole moment. Because of its strong nuclear octupole deformation and large atomic mass, (225)Ra is particularly sensitive to interactions in the nuclear medium that violate both time-reversal symmetry and parity. We have developed a cold-atom technique to study the spin precession of (225)Ra atoms held in an optical dipole trap, and demonstrated the principle of this method by completing the first measurement of its atomic electric dipole moment, reaching an upper limit of |d((225)Ra)|<5.0×10(-22)  e cm (95% confidence).

  1. Data of evolutionary structure change: 1E1RA-2HLDT [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E1RA-2HLDT 1E1R 2HLD A T DLEETGRVLSIGDGIARVHGLRNVQAEEMVEFSSGLKGM...VDALVPIGRGQRELIIGDRQTGKTAVALDTILNQKRWNNGSDESKKLYCVYVAVGQKRSTVAQLVQTLEQHDAMKYSIIVAATASEAAPLQYLAPFTAASIGEWFRDN...bChain>T 2HLDT ALKQVAGSLKLFL

  2. First Measurement of the Atomic Electric Dipole Moment of $^{225}$Ra

    CERN Document Server

    Parker, R H; Kalita, M R; Lemke, N D; Bailey, K G; Bishof, M N; Greene, J P; Holt, R J; Korsch, W; Lu, Z -T; Mueller, P; O'Connor, T P; Singh, J T

    2015-01-01

    The radioactive radium-225 ($^{225}$Ra) atom is a favorable case to search for a permanent electric dipole moment (EDM). Due to its strong nuclear octupole deformation and large atomic mass, $^{225}$Ra is particularly sensitive to interactions in the nuclear medium that violate both time-reversal symmetry and parity. We have developed a cold-atom technique to study the spin precession of $^{225}$Ra atoms held in an optical dipole trap, and demonstrated the principle of this method by completing the first measurement of its atomic EDM, reaching an upper limit of $|$$d$($^{225}$Ra)$|$ $<$ $5.0\\!\\times\\!10^{-22}$ $e \\cdot$cm (95$\\%$ confidence).

  3. Neuroprotective actions of endogenous interleukin-1 receptor antagonist (IL-1ra) are mediated by glia.

    Science.gov (United States)

    Pinteaux, Emmanuel; Rothwell, Nancy J; Boutin, Herve

    2006-04-01

    The pro-inflammatory cytokine interleukin-1 (IL-1), contributes to neuronal inflammation and cell death induced by ischemia, excitotoxicity, or trauma, while administration of IL-1 receptor antagonist (IL-1ra) reduces neuronal injury. The aim of the present study was to test the hypothesis that endogenous IL-1ra is neuroprotective in vivo and in vitro, and to identify its mechanism of actions. Mice lacking IL-1ra (IL-1ra knock-out (KO]) exhibited a dramatic increase in neuronal injury (3.6-fold increase in infarct size) induced by transient cerebral ischemia compared to wild-type (WT) animals. Basal cell death of cultured cortical neurons from WT and IL-1ra KO was identical, and treatment with NMDA or AMPA (20 microM) increased cell death to the same extent in WT and IL-1ra KO neurons. However, basal and NMDA- or AMPA-induced cells death was significantly higher in glial-neuronal co-cultures from IL-1ra KO than from WT mice. We further showed that pure microglial cultures, but not pure astrocytes cultures, released IL-1ra in response to treatment with conditioned medium from NMDA- or AMPA-treated primary neurons. These results demonstrate that endogenous IL-1ra produced by microglia is neuroprotective in cerebral ischemia or excitotoxicity.

  4. Separation Sr and Ba From Fission Products Using Sr-spec Resin Column

    Institute of Scientific and Technical Information of China (English)

    WANG; Xiu-feng

    2013-01-01

    Sr and Ba are the IIA group elements,with the same outer electronic structure,and the very similar properties,so separation of the two elements becomes very difficult.The traditional separation method of Sr and Ba in fission products is repeated precipitation of BaCl2·H2O in hydrochloric acid-ether medium.Four times repeated precipitation steps are needed to ensure the decontamination factor of Sr to be better

  5. Joseph C. Risser Sr., 1892–1982

    OpenAIRE

    Manring, M. M.; Calhoun, Jason

    2009-01-01

    This biographical sketch of Joseph C. Risser Sr. corresponds to the historic text, The Classic: The Iliac Apophysis: An Invaluable Sign in the Management of Scoliosis, available at DOI 10.1007/s11999-009-1096-z.

  6. Luminescence and scintillation properties of Tl- and In-doped CsCl crystals

    Science.gov (United States)

    Sakai, Takumi; Koshimizu, Masanori; Fujimoto, Yutaka; Nakauchi, Daisuke; Yanagida, Takayuki; Asai, Keisuke

    2017-06-01

    Optical and scintillation properties of CsCl:Tl and CsCl:In single crystals were investigated. Ions Tl+ and In+ were selected as dopants to enhance the light yield of CsCl crystals. Luminescence and scintillation spectra of CsCl:Tl and CsCl:In could be attributed to the relaxed excited state (RES) originating from each dopant ion. The decay-time constants of the fast component had values of 5.4 ns for CsCl:Tl and 2.2 ns for CsCl:In, and can be ascribed to the overlapping of on-center STE and auger-free luminescence (AFL) for CsCl:Tl and only AFL for CsCl:In, respectively. Decay-time constants of the slow component were relatively long (220 ns for CsCl:Tl and 240 ns for CsCl:In), possibly owing to their low energy transfer rate from host to each dopant ion. The light yields of CsCl:1%Tl and CsCl:0.5%Tl were estimated to be 2800 and 2200 photons/MeV, respectively. The light yield of CsCl:0.5%In crystals was estimated to be 2200 photons/MeV. In conclusion, the light yield of pure CsCl (several ten photons/MeV) can be enhanced by doping Tl+ and In+ while maintaining the fast component of the CsCl crystal.

  7. Radiogenotoxicological effect of signal nuclide 134Cs on somatic and germ cells

    Institute of Scientific and Technical Information of China (English)

    ZhuShou-Peng; XiaFen; 等

    1997-01-01

    Chromosome at aberation rates in bone marrow cells and micronucleus formation in bone marrow polychromatic erythrocytes both rise with increase in radioactivities of 134Cs,and can be fitted to power functions of radioactivities of 134Cs.In spermatogonia 134Cs mainly induced chromatid breakage,and abnormalities in sperm can also be experessed as power functions of radioactivities of 134 Cs.

  8. Radiogenic and stable Sr isotope ratios (87Sr/86Sr, δ88/86Sr) as tracers of riverine cation sources and biogeochemical cycling in the Milford Sound region of Fiordland, New Zealand

    Science.gov (United States)

    Andrews, M. Grace; Jacobson, Andrew D.; Lehn, Gregory O.; Horton, Travis W.; Craw, Dave

    2016-01-01

    This study reports radiogenic Sr isotope ratios (87Sr/86Sr), stable Sr isotope ratios (δ88/86Sr), and major ion concentrations for river, rock, sediment, soil, and plant samples collected from the Cleddau and Hollyford catchments in the Milford Sound region of Fiordland, New Zealand. The catchments primarily drain gabbro, but some tributaries access limestone and volcanogenic sediments. The goal of the study was to understand controls on riverine δ88/86Sr values in a landscape with multiple factors that may influence chemical weathering, including dense vegetation, high rainfall, and abundant, freshly-eroded Holocene fluvio-glacial and landslide debris. Rivers draining gabbro have higher δ88/86Sr values than bedrock, by as much as ∼0.14‰, and the δ88/86Sr values strongly correlate with molar Ca/Sr ratios (R2 = 0.69). Leaching of rocks and sediment reveals no evidence for the preferential dissolution of minerals having high δ88/86Sr values and Ca/Sr ratios. In-stream Sr isotope fractionation seems unlikely because comparison against 87Sr/86Sr and Ca/Sr ratios demonstrates that riverine δ88/86Sr values conservatively trace water-mass mixing. The riverine data are best explained by the input of soil water, which is distinct from potential bedrock end-members (i.e., silicates and carbonates) based on δ88/86Sr but indistinguishable in terms of Ca/Sr and 87Sr/86Sr. While strontium isotope fractionation during secondary mineral formation and pedogenesis is possible, clay mineral formation is minor and most soils are poorly developed. Instead, soil water δ88/86Sr values more likely reflect plant uptake. Plant samples yielded a wide range of δ88/86Sr values, but on average, they are lower than those for bedrock, consistent with the expectation that plants preferentially incorporate lighter Sr isotopes. Mass-balance constraints, together with 87Sr/86Sr ratios, indicate that soil water δ88/86Sr values are ∼0.30‰ higher than bedrock δ88/86Sr values, and

  9. Development of Jacketing Technologies for Iter CS and TF Conductor

    Science.gov (United States)

    Hamada, K.; Nakajima, H.; Matsui, K.; Kawano, K.; Takano, K.; Tsutsumi, F.; Okuno, K.; Teshima, O.; Soejima, K.

    2008-03-01

    The Japan Atomic Energy Agency (JAEA) has developed jacketing technologies for ITER Toroidal Field (TF) and Central Solenoid (CS) conductor. Full scale TF and CS conduits were fabricated using carbon-reduced SUS316LN and boron-added (˜40 ppm) high manganese stainless steel (0.025C -22Mn -13Cr -9Ni -0.12N: JK2LB), respectively. Welding condition was optimized so that back bead does not interfere a cable insertion. The weld joint samples were compacted by a compaction machine that was newly constructed and tested at 4.2 K. Mechanical characteristics at 4K of CS, TF conduits and CS welded joint satisfied ITER mechanical requirements. TF welded joint shows slightly lower value of 0.2% yield strength (885 MPa) than that of ITER requirement (900 MPa). The TF conduit contains nitrogen content of 0.14%, which is minimum value in ITER specification. The lower nitrogen content may be caused by the release of nitrogen from molten metal during non-filler welding resulting in a 4 K strength decrease. To satisfy the ITER requirements, minimum nitrogen contents of conduit should be increased from 0.14% to 0.15% at least. Therefore, JAEA successfully developed TF and CS conduits with welding technologies and finalized the procurement specification for ITER conductor jacketing.

  10. Energy resolution of CsI(Na) scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Syntfeld-Kazuch, A., E-mail: syntfeld@ipj.gov.p [Andrzej Soltan Institute for Nuclear Studies, PL-05-400 Otwock-Swierk (Poland); Sibczynski, P.; Moszynski, M. [Andrzej Soltan Institute for Nuclear Studies, PL-05-400 Otwock-Swierk (Poland); Gektin, A.V. [Institute for Scintillation Materials, 60 Lenin Ave., 61001 Kharkov (Ukraine); Czarnacki, W.; Grodzicka, M.; Iwanowska, J.; Szawlowski, M.; Szczesniak, T.; Swiderski, L. [Andrzej Soltan Institute for Nuclear Studies, PL-05-400 Otwock-Swierk (Poland)

    2010-03-15

    The presented paper on CsI(Na) scintillators is a continuation of systematical studies of alkali halide crystals exhibiting more than one exponential decay time. The CsI(Na) crystals are known to have short ({approx}550 ns) and long (few microseconds) components in the scintillation pulse. Previous studies showed that integration of slow components of the light pulse improved the light output, non-proportionality and energy resolution of CsI(Tl), NaI(Tl) in lower temperatures and undoped NaI crystal at liquid nitrogen temperature. In this work, an influence of the shaping time in the spectroscopy amplifier on the light output, non-proportional response to {gamma}-rays, and energy resolution of two different size CsI(Na) scintillators is examined. Each crystal was coupled to the Photonis XP5212 PMT with a photocathode blue sensitivity of 12.2 {mu}A/l mF. The data analysis showed improved proportionality of the crystal response, higher number of photoelectrons/MeV-{gamma}, and consequently, a better overall energy resolution obtained for 12 {mu}s shaping time constant. Finally, the CsI(Na) characteristics are compared to that obtained previously for NaI(Tl).

  11. {sup 137} Cs as a tracer of the Catalan current

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Cabeza, J.A.; Molero, J.; Merino, J.; Pujol, L. [Universidad Autonoma de Barcelona (Spain); Mitchell, P.I. [University Coll., Dublin (Ireland). Dept. of Physics

    1995-12-31

    A number of nuclear power installations located in the north-western Mediterranean (NWM) area are known to enhance {sup 137}Cs levels in various marine compartments. The nuclear fuel reprocessing plant at Marcoule (France) has been reported to originate a significant increase of {sup 137}Cs in Rhone river waters and sediments because of the discharge of low-level liquid radioactive waste. This radionuclide may be used as a tracer of oceanographic processes in the NWM; in fact, {sup 137}Cs of Rhone river origin has been detected in the Gulf of Lions by several authors. The results reported in this work correspond to various transect experiments in waters of the Catalan Sea and show that: (i) surface salinity measurements confirmed the presence of the Catalan current in the Cap de Creus area; (ii) the 1991 Cap de Creus transect showed clearly the presence of {sup 137}Cs above a baseline level of 4.3 {+-} 0.2 Bq.m{sup -3}; (iii) the Cap de Salou transect showed elevated levels towards the coast; (iv) the 1992 Cap de Creus transect showed no structure at all. Therefore, it was concluded that traces of {sup 137}Cs from the Marcoule nuclear fuel reprocessing plant were transported by the Catalan current and were detectable in the Catalan Sea with a complex spatio-temporal structure. (authors). 25 refs., 4 figs.

  12. Association between anti-Porphyromonas gingivalis or anti-α-enolase antibody and severity of periodontitis or rheumatoid arthritis (RA) disease activity in RA.

    Science.gov (United States)

    Lee, Joo Youn; Choi, In Ah; Kim, Jin-Hee; Kim, Kyoung-Hwa; Lee, Eun Young; Lee, Eun Bong; Lee, Yong-Moo; Song, Yeong Wook

    2015-08-12

    Periodontitis (PD) has been reported to be associated with rheumatoid arthritis (RA). Porphyromonas gingivalis (P. gingivalis) is a gram-negative anaerobic bacterium that is recognized as one of the major pathogenic organisms in PD and is the only bacterium known to express peptidylarginine deiminase (PAD). Antibody against human α-enolase (ENO1) is one of the autoantibodies in RA. ENO1 is a highly conserved protein, and could be a candidate molecule for molecular mimicry between bacterial and human proteins. In the present study, we measured serum antibody against P. gingivalis and human ENO1 in patients with RA and investigated their association with the severity of PD or disease activity of RA. Two hundred, forty-eight patients with RA and 85 age- and sex-matched healthy controls were evaluated by rheumatologic and periodontal examinations. The serum levels of anti-P. gingivalis and anti-ENO1 antibodies were measured by an enzyme-linked immunosorbent assay (ELISA). Patients with RA had significantly higher levels of anti-P. gingivalis and anti-ENO1 antibody titers than the controls (p = 0.002 and 0.0001, respectively). Anti-P. gingivalis antibody titers significantly correlated with anti-ENO1 antibody titers in RA patients (r = 0.30, p < 0.0001). There were significant correlations between anti-P. gingivalis antibody titers and the gingival index (GI), probing pocket depth (PPD), bleeding on probing (BOP) and clinical attachment level (CAL) (p = 0.038, 0.004, 0.004 and 0.002, respectively) in RA. Anti-P. gingivalis antibody titers were not correlated with disease activity score 28 (DAS28) or anti-CCP titer. However, anti-ENO1 antibody titers were significantly correlated not only with the periodontal indices, such as PPD, BOP, and CAL (p = 0.013, 0.023 and 0.017, respectively), but also RA clinical characteristics, such as DAS28, anti-CCP titer, and ESR (p = 0.009, 0.015 and 0.001, respectively). Anti-P. gingivalis and anti-ENO1 antibody

  13. Evaluation of the activity concentration of {sup 226}Ra, {sup 228}Ra and {sup 210}Pb in sediments from Antarctica in the Admiralty Bay region

    Energy Technology Data Exchange (ETDEWEB)

    Mora, Tamires de A.; Oliveira, Joselene de, E-mail: tamires.mora@usp.br, E-mail: jolivei@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Figueira, Rubens C.L.; Mahiques, Michel M.; Sousa, Silvia H.M., E-mail: rfigueira@usp.br, E-mail: mahiques@usp.br, E-mail: smsousa@usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto Oceanografico

    2015-07-01

    In this study, we performed the radiochemical characterization of a sedimentary record (1B profile), collected in the vicinity of Admiralty Bay, King George Island in Antarctic Operation XXXI (January/2013). The activities of {sup 226}Ra, {sup 228}Ra and {sup 210}Pb were determined by the counting of gross alpha and gross beta activities in the precipitates of Ba(Ra)SO{sub 4} and PbCrO{sub 4}. Those measurements were carried out in a low background gas flow proportional detector. The {sup 226}Ra and {sup 228}Ra were measured after 21 days of the final precipitation. The {sup 210}Pb activity was determined after 10 days of the precipitation date by gross beta counting of its {sup 210}Bi decay product. The activity concentration of {sup 226}Ra ranged from 11±1 (mBq g-1) to 54±3 (mBq g{sup -1}), and the {sup 228}Ra ranged from 48±5 (mBq g{sup -1}) to 155±16 (mBq g{sup -1}). The activity concentration of {sup 210}Pb varied from 8±1 (mBq g{sup -1}) to 458±46 (mBq g{sup -1}), while unsupported {sup 210}Pb ranged from 6±1 (mBq g{sup -1}) to 434±65 (mBq g{sup -1}). The {sup 210}Pb concentrations in sediments have often been used to dating events like deposition and accumulation in various marine environments. Taking into account the results of {sup 210}Pb and {sup 226}Ra activities obtained in testimony-1B it was estimated the unsupported {sup 210}Pb activity which was applied to the CIC geochronological dating model (Constant Initial Concentration). Based in these data, the sedimentation rate obtained was 0.63±0.02 cm year{sup -1}. (author)

  14. In situ7Li and 133Cs nuclear magnetic resonance investigations on the role of Cs+ additive in lithium-metal deposition process

    Science.gov (United States)

    Hu, Jian Zhi; Zhao, Zhenchao; Hu, Mary Y.; Feng, Ju; Deng, Xuchu; Chen, Xilin; Xu, Wu; Liu, Jun; Zhang, Ji-Guang

    2016-02-01

    Cesium ion (Cs+) has been reported to be an effective electrolyte additive to suppress Li dendrite growth which prevents the application of lithium (Li) metal as an anode for rechargeable Li batteries. In this work, we investigated the effect of Cs+ additive on Li depositions using quantitative in situ7Li and 133Cs nuclear magnetic resonance (NMR) with planar symmetric Li cells. It's found that the addition of Cs+ can significantly enhance both the formation of well aligned Li nanorods and reversibility of the Li electrode. In situ133Cs NMR directly confirms that Cs+ migrates to Li electrode to form a positively charged electrostatic shield during the charging process. Much more electrochemical "active" Li was found in Li films deposited with Cs+ additive, while more electrochemical "dead" and thicker Li rods were identified in Li films deposited without Cs+. Combining the in situ and the previous ex-situ results, a Li deposition model has been proposed to explain these observations.

  15. Factors Controlling the Groundwater Transport of U, Th, Ra, and Rn

    Indian Academy of Sciences (India)

    A Tricca; D Porcelli; G J Wasserburg

    2000-03-01

    A model for the groundwater transport of naturally occurring U, Th, Ra, and Rn nuclides in the 238U and 232Th decay series is discussed. The model developed here takes into account transport by advection and the physico-chemical processes of weathering, decay, -recoil, and sorption at the water-rock interface. It describes the evolution along a flowline of the activities of the 238U and 232Th decay series nuclides in groundwater. Simple sets of relationships governing the activities of the various species in solution are derived, and these can be used both to calculate effective retardation factors and to interpret groundwater data. For the activities of each nuclide, a general solution to the transport equation has been obtained, which shows that the activities reach a constant value after a distance $\\bar{x}_i$, characteristic of each nuclide. Where $\\bar{x}_i$ is much longer than the aquifer length, (for 238U, 234U, and 232Th), the activities grow linearly with distance. Where $\\bar{x}_i$ is short compared to the aquifer length, (for 234Th, 230Th, 228Th, 228Ra, and 224Ra), the activities rapidly reach a constant or quasi-constant activity value. For 226Ra and 222Rn, the limiting activity is reached after 1 km. High 234U values (proportional to the ratio 234Th/W238U) can be obtained through high recoil fraction and/or low weathering rates. The activity ratios 230Th/232Th, 228Ra/226Ra and 224Ra/226Ra have been considered in the cases where either weathering or recoil is the predominant process of input from the mineral grain. Typical values for weathering rates and recoil fractions for a sandy aquifer indicate that recoil is the dominant process for Th isotopic ratios in the water. Measured data for Ra isotope activity ratios indicate that recoil is the process generally controlling the Ra isotopic composition in water. Higher isotopic ratios can be explained by different desorption kinetics of Ra. However, the model does not provide an explanation for 228Ra

  16. Rb-Sr Isotopic Systematics of Alkali-Rich Fragments in the Yamato-74442 LL-Chondritic Breccia

    Science.gov (United States)

    Yokoyama, T.; Misawa, K.; Okano, O.; Shih, C.-Y.; Nyquist, L. E.; Simo, J. I.; Tappa, M. J.; Yoneda, S.

    2012-01-01

    Alkali-rich igneous fragments were identified in the brecciated LL-chondrites, Kr henberg (LL5)], Bhola (LL3-6) and Yamato (Y)-74442 (LL4), and show characteristic fractionation patterns of alkaline elements. The K-Rb-Cs-rich fragments in Kr henberg, Bhola, and Y-74442 are very similar in mineralogy and petrography (olivine + pyroxene + glass), suggesting that they could have come from related precursor materials. We have undertaken Rb-Sr isotopic studies on alkali-rich fragments in Y-74442 to precisely determine their crystallization ages and the isotopic signatures of their precursor material(s).

  17. Accumulation of K+ and Cs+ in Tropical Plant Species

    Science.gov (United States)

    Velasco, H.; Anjos, R. M.; Zamboni, C. B.; Macario, K. D.; Rizzotto, M.; Cid, A. S.; Medeiros, I. M. A.; Fernández, J.; Rubio, L.; Audicio, P.; Lacerda, T.

    2010-08-01

    Concentrations of K+ and 137Cs+ in tissues of the Citrus aurantifolia were measured both by gamma spectrometry and neutron activation analysis, aiming to understand the behavior of monovalent inorganic cations in plants as well as its capability to store these elements. In contrast to K+, Cs+ ions are not essential elements to plants, what might explain the difference in bioavailability. However, our results have shown that 137Cs+ is positively correlated to 40K+ concentration within tropical plant species, suggesting that these elements might be assimilated in a similar way, and that they pass through the biological cycle together. A simple mathematical model was also proposed to describe the temporal evolution of 40K activity concentration in such tropical woody fruit species. This model exhibited close agreement with the 40K experimental results in the fruit ripening processes of lemon trees.

  18. Zulliger (CS in Assessing the Relational Maturity of Children

    Directory of Open Access Journals (Sweden)

    Anna Elisa Villemor-Amaral

    Full Text Available Abstract Relational maturity is an important aspect to be considered in the evaluation of children. Its development in children is considered related to sex and chronological age. The present study aimed to seek evidence of validity for the Zulliger test (Comprehensive System - CS in the evaluation of maturity for interpersonal relationships in children. A total of 566 children, both sexes, of which 52.8% were girls, were submitted to the Zulliger test (CS. For comparison according to age, a subsample was extracted, composed of two groups of six and 12-year-olds, totaling 115 children. The analysis revealed statistically significant differences in the variables H, (H, A, Ad, (A, M, FC and AG. Results show findings in favor of using the Zulliger test (CS in the evaluation of maturity for interpersonal relationships in children.

  19. Towards a quantum gas of polar YbCs molecules

    Science.gov (United States)

    Freytag, R.; Petersen, M.; Hinds, E. A.; Tarbutt, M.; Butler, K.; Kemp, S.; Hopkins, S. A.; Brue, D. A.; Hutson, J. M.; Cornish, S. L.

    2013-05-01

    The potentials of ultracold polar molecules have been discussed with respect to quantum information processing and quantum simulation. This experiment focuses on the production of quantum degenerate YbCs molecules. We propose to magneto-associate the atoms over a Feshbach resonance and transfer them to the ground state using Stimulated Raman Adiabatic Passage (STIRAP). Ground state YbCs will, due to its single valence electron, exhibit an electric as well as a magnetic dipole moment. It should therefore demonstrate spin dependent interactions in addition to long-range dipole-dipole interactions. Here we outline the theoretical and experimental progress on creating a dual species Magneto-Optical Trap (MOT) of Yb and Cs. ESPRC

  20. Precision measurement of the ionization energy of Cs I

    CERN Document Server

    Deiglmayr, Johannes; Saßmannshausen, Heiner; Jansen, Paul; Schmutz, Hansjürg; Merkt, Frédéric

    2016-01-01

    We present absolute-frequency measurements for the transitions from the 6s$_{1/2}$ ground state of $^{133}$Cs to $n$p$_{1/2}$ and $n$p$_{3/2}$ Rydberg states. The transition frequencies are determined by one-photon UV spectroscopy in ultracold samples of Cs atoms using a narrowband laser system referenced to a frequency comb. From a global fit of the ionization energy $E_\\mathrm{I}$ and the quantum defects of the two series we determine an improved value of $E_\\mathrm{I} = h c \\cdot 31 406.467 732 5(14)$ cm$^{-1}$ for the ionization energy of Cs with a relative uncertainty of $5\\times10^{-11}$. We also report improved values for the quantum defects of the $n$p$_{1/2}$, $n$p$_{3/2}$, $n$s$_{1/2}$, and $n$d$_{5/2}$ series.