WorldWideScience

Sample records for biomonitoring neutron activation

  1. The role of neutron activation analysis in nutritional biomonitoring programs

    International Nuclear Information System (INIS)

    Nutritional biomonitoring is a multidisciplinary task and an integral part of a more general bioenvironmental surveillance. In its comprehensive form, it is a combination of biological, environmental, and nutrient monitoring activities. Nutrient monitoring evaluates the input of essential nutrients required to maintain vital bodily functions; this includes vigilance over extreme fluctuations of nutrient intake in relation to the recommended dietary allowances and estimated safe and adequate daily dietary intakes and adherence to the goals of provisional tolerance limits. Environmental monitoring assesses the external human exposure via ambient pathways, namely, air, water, soil, food, etc. Biological monitoring quantifies a toxic agent and its metabolites in representative biologic specimens of an exposed organ to identify health effects. In practice, coordinating all three components of a nutritional biomonitoring program is complex, expensive, and tedious. Experience gained from the US National Health and Nutrition Examination Surveys demonstrates the problems involved. By far the most critical challenge faced here is the question of analytical quality control, particularly when trace element determinations are involved. Yet, measures to ensure reliability of analytical data are mandatory, and there are no short-cuts to this requirement. The purpose of this presentation is to elucidate the potential of neutron activation analysis (NAA) in nutritional biomonitoring activities

  2. Air pollution biomonitoring in Argentina, application of neutron activation analysis to the study of biomonitors

    International Nuclear Information System (INIS)

    The assessment of baseline levels of atmospheric pollutants and the identification of polluted areas is a complex problem, as pollutant contents at a certain geographical location is usually a combination of contributions from various diverse sources, including long-range transport. Elemental chemical characterization of atmospheric pollutants is thus of great importance and Neutron Activation Analysis has proved to be a powerful technique for multielemental determination of trace elements in biomonitors and aerosols. The general objective of this project is to study the use of biomonitors, specially lichens, for evaluating pollutant levels over a wide geographic area of Argentina and for establishing baseline values and assessing time trends. Two lichen species (Usnea sp. and Ramalina ecklonii (Spreng.) Mey. and Flot) have been identified as suitable monitors of air pollution, with potential regional application at the central area of the country (province of Cordoba) and pilot studies have been initiated to test the practicability of sampling and sample collection. An area of approximately 40,000 km2 will be covered by a sampling network, using in situ growing lichens. The distribution maps for the two selected species are already drawn and sampling of local soils will also be conducted. Current efforts at the Neutron Activation Analysis laboratory are put on assessing, for the selected lichen species, the influence of sample preparation methods on trace element concentrations. The use of other analytical techniques will allow the evaluation of the bioindicator chemical response and its relationship to different atmospheric quality levels. Source identification and apportionment will be done by statistical fingerprinting of the elemental concentrations, as sources of pollution are characterized by being composed of different mixtures of elements in different proportions. In this way and as a long-term objective, regional maps will be drawn showing the

  3. Air pollution biomonitoring in Argentina, application of neutron activation analysis to the study of biomonitors

    International Nuclear Information System (INIS)

    Due to low population density, total air pollutant emissions in Argentina are still low if compared with highly industrialised countries. Although a significant deterioration of air quality has been observed for a long time, air monitoring did not begin until the 90's and only in a few cities. The use of air pollution biomonitors represents an important contribution to Argentina, as measurements of air pollutants in large areas would require especial technical equipment not easily available and operated. In this project, two lichen species (Ramalina ecklonii (Spreng) Mey and Flot and Usnea amblyoclada (Muell. Rg.) Zahlbr.) and a Bromeliaceae (Tillandsia capillaris) are used as biomonitors of air pollution at a 50, 000 km2 area in Cordoba province (central Argentina). AAS and INAA have been applied for the analysis of samples, determining As, Ba, Br, Ce, Co, Cr, Cs, Cu, Eu, Fe, Hf, Gd, K, La, Lu, Mn, Na, Ni, Pb, Rb, Sb, Sc, Sm, Ta, Tb, Th, U, Yb and Zn. The following physiological parameters were also determined: chlorophyll a, chloropyll b, phaeophytin a, phaeophytin b, hydroperoxy conjugated dienes, malonaldehide and sulphur. Some of these parameters were used for calculating a pollution index. These determinations were carried out on pools collected at the sampling sites. AAS and physiological parameters were also applied to the analysis of five-replicate samples in order to study variability sources. For data evaluation, different statistical and other evaluating tools were used: descriptive statistics and Spearman's correlation analysis were used on data from the three biomonitor species while factor analysis and mapping, only for R. ecklonii results. (author)

  4. Instrumental neutron activation analysis and inductively coupled plasma mass spectrometry on atmospheric biomonitors

    International Nuclear Information System (INIS)

    In a biomonitoring study aiming to find alternatives to lower epiphytes as air-quality monitors, lichens and tree bark were exposed at different sites for discontinuous periods of 2 months and continuously. Native lichens were collected as well. The contents for 22 elements were obtained by both instrumental neutron activation analysis (INAA) and inductively coupled plasma mass spectrometry (ICP-MS). Quality control as asserted by analyzing ISE-921, NIST-1547 and TL-1 was good. Losses of As and Se by volatilization during sample digestion and neutron irradiation were evident; Ca contents by ICP-MS appeared underestimated probably due to the formation of the insoluble fluoride. ICP-MS featured a better precision than INAA. Nonparametric statistics were applied to the ICP-MS replicates, to those determined by INAA, and to compare the results of both techniques. High or even excellent correlations were found between replicates in INAA, whereas, in ICP-MS, Cr and Ta were just fairly or not correlated. As an overall comparison of the techniques, biased results were found for As, Ba, Ce, Cr, Cs, Hf, La, Sc, Se, Ta, and Zn; unbiased results could be found for Ca, Co, Fe, K, Na, Rb, Sb, Sm, Tb, Th, and U. (author)

  5. Neutron activation analysis of atmospheric biomonitors from the Azores. A comparative study of lower and higher plants

    International Nuclear Information System (INIS)

    Within an extensive survey of lower and higher plants in the Azores' Terceira and Santa Maria islands, this study is focused on the evaluation of ectohydric bryophytes and bark from Cryptomeria japonica as an alternative to epiphytic lichens for air-monitoring purposes. Neutron activation analysis (k0-NAA) has been applied to all field samples for elemental determinations. Judging from the present results, and since the islands embody most features of the whole archipelago, bryophytes do not appear as an option for further campaigns in the Azores, due to scanty supply and relatively poor performance as biomonitors. On the other hand, comparisons of bark with lichens collected at the same sites seem fairly good, and elements are enriched in bark to an even greater extent than in lichens. All things considered - including material availability and ecological concern - bark stands for a sensible choice for biomonitoring in the Azores. (author)

  6. Determination of I-129 in biomonitors collected in the vicinity of a nuclear power plant by neutron activation analysis

    Czech Academy of Sciences Publication Activity Database

    Krausová, Ivana; Kučera, Jan; Světlík, Ivo

    2013-01-01

    Roč. 295, č. 3 (2013), s. 2043-2048. ISSN 0236-5731 R&D Projects: GA ČR(CZ) GBP108/12/G108; GA MŠk(XE) LM2011019 Institutional support: RVO:61389005 Keywords : I-129 * biomonitor * Thyroid gland * neutron activation analysis * nucelar power plant Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.415, year: 2013 http://link.springer.com/content/pdf/10.1007%2Fs10967-012-2200-5

  7. Determination of 129 I in biomonitors collected in the vicinity of a nuclear power plant by neutron activation analysis

    Czech Academy of Sciences Publication Activity Database

    Krausová, Ivana; Kučera, Jan; Světlík, Ivo

    2012-01-01

    Roč. 293, 13Sep2012 (2012), s. 1-6. ISSN 1588-2780 R&D Projects: GA ČR(CZ) GBP108/12/G108; GA MŠk(XE) LM2011019 Institutional support: RVO:61389005 Keywords : Iodine-129 * neutron activation analysis * biomonitor * nuclear power plant * Thyroid gland Subject RIV: CB - Analytical Chemistry, Separation http://download.springer.com/static/pdf/725/art%253A10.1007%252Fs10967-012-2200-5.pdf?auth66=1361263915_42267d28376ca81c4fc0de53c3cb59f4&ext=.pdf

  8. Atmospheric Deposition of Heavy Metals in Serbia Studied by Moss Biomonitoring, Neutron Activation Analysis and GIS Technology

    CERN Document Server

    Frontasyeva, M V; Kumar, M; Matavuly, M; Pavlov, S S; Radnovic, D; Steinnes, E

    2002-01-01

    The results of a pilot study on atmospheric deposition of heavy metals and other trace elements using the moss biomonitoring technique in the northern part of Serbia and some areas of Bosnia are presented. Samples of Hypnum cupressiforme along with some other moss types were collected at 92 sites during the summer of 2000. A total of 44 elements were determined by instrumental neutron activation analysis using epithermal neutrons. The observed levels of Cu, Zn, As, Ag, Cd, In, Sb, etc. in the area surrounding the town of Bor (Serbia) are comparable to those reported from similar industrial areas in other countries such as the Copper Basin in Poland and the South Urals of Russia. In the same region the maximum Se and Mo concentrations are the highest ever recorded in biomonitoring studies using mosses. High median concentrations of Fe and Ni in Serbian mosses are associated with a crustal component as apparent from factor analysis of the moss data. This component could be a result of windblown soil dust (most ...

  9. Biomonitoring of occupational exposure: Neutron activation determination of selected metals in the body tissues and fluids of workers manufacturing stainless steel vessels

    Czech Academy of Sciences Publication Activity Database

    Kučera, Jan; Bencko, V.; Tejral, J.; Borská, L.; Soukal, L.; Řanda, Zdeněk

    2004-01-01

    Roč. 259, č. 1 (2004), s. 7-11. ISSN 0236-5731 R&D Projects: GA AV ČR KSK4055109 Institutional research plan: CEZ:AV0Z1048901 Keywords : occupational exposure * biomonitoring * neutron activation analysis Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 0.457, year: 2004

  10. The use of biomonitors and neutron activation analysis in the study of air pollution of Buenos Aires city

    International Nuclear Information System (INIS)

    Biomonitors were used as part of a pollution study of Buenos Aires city atmosphere under the International Atomic Energy Agency Research Contract ARG 7251, from the Co-ordinated Research Programme on Applied Research on Air Pollution using Nuclear Related Analytical Techniques. Lichens were primarily selected as indicators. Two different approaches were conducted, direct sampling of Parmotrema reticulatum, at a few places and the use of lichen bags, filled with Usnea sulcata from a northern national park, and hung at different sites. Simultaneously, tree bark was tried as biomonitor. Platanus acerifolia and Melia azedarach were selected as candidates, for being the most common trees in the city, but only P. acerifolia was analyzed. All the samples were analyzed using instrumental neutron activation analysis at the Ezeiza Atomic Centre of the National Atomic Energy Commission. RA-3) reactor was used for the irradiations, determining: As, Ba, Br, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Rb, Sb, Sc, Sm, Ta, Tb, Th, U, Yb and Zn. Concentration values for P. reticulatum compared well with values from literature. For U. sulcata differences were found among the tested sites and also, for some elements an increasing trend with time was observed. Enrichment factors calculated using Sc as reference and Mason's crustal average concentrations showed vehicules and refuse incineration as contributing sources to the aerosol. Tree bark from Buenos Aires and from a smaller city with mainly agricultural activities were analyzed and the results are coincident with those from lichens. This work is the first and preliminar contribution to the study of Buenos Aires aerosol using biomonitors. (author)

  11. Study on air pollution around China's largest oil refinery complex using multielements in biomonitors and neutron activation analysis techniques

    International Nuclear Information System (INIS)

    Three different kinds of plant leaves, Chinese white poplar, arborvitae and pine needle have been sampled from different places, Yanshan Oil refinery complex, Capital Iron and Steel Factory and Badachu, a control place in Beijing, as bio-monitors for air pollution studies. Each sample was divided into two parts, washed and unwashed, 31 trace elements, As, Au, Br, Ca, Cd, K, La, Lu, Mo, Na, Sb, Sm, U, W, Yb, Ba, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, Rb, Sc, Se, Sr, Ta, Tb, Th and Zn have been determined by using KO method of instrument neutron activation analysis techniques with a long irradiation in the 15MW Heave Water Research Reactor, China Institute of Atomic Energy. The results indicated that: 1) the concentration of trace elements in unwashed samples are much higher than that in washed samples; 2) the area of capital iron and steel factory is polluted heavily, and Yanshan oil refinery complex area is polluted moderately, 3) All the three kinds of plant leaves can be used as air pollution biomonitors, because they can absorb some trace elements from the air pollutants. Aspen is good for monitoring in particular seasons and Pine needle is better than arborvitae for yearly monitoring; 4) Elements of As, Cd, Hg, Co, Rb, Sb, W and Zn are highly absorbed by Chinese white poplar. Pine needle is sensitive to absorb the elements of Br, Cr, Cd, Fe, Sc, Cs and rear earth elements, but arborvitae is very sensitive for the absorption of Sr. (author)

  12. Biomonitoring of air pollution with heavy metals in the Republic of Macedonia by neutron activation analysis

    International Nuclear Information System (INIS)

    Atmospheric deposition of trace metals was studied over the entire territory of the Republic of Macedonia in 2002 and 2005. Samples of the terrestrial mosses Hypnum cupressiforme, Camptothecium lutescens, and Homalothecium sericeum were collected at 73 sites in 2002 and at 72 sites in 2005. Instrumental neutron activation analysis allowed determination of 41 elements in 2002 and 38 elements in 2005. Principal component factor analysis was used to identify the most polluted areas and characterize different pollution sources. The most important sources of trace metal deposition are ferrous and non-ferrous smelters, oil refineries, fertilizer production plants, and central heating station. four areas appear to be particularly exposed to metal pollution: Veles, Skopje, Tetovo, and Kavadarci - Negotino. Comparison of the results from the first and the second moss survey, showed that there is no significant difference in median values of elemental concentrations determined, besides Ni. The more then twofold increase of its median value is explained by renewed activity of ferronickel smelter in Kavadartsi. (Author)

  13. Study of antarctic lichens as environmental biomonitors in the Admiralty Bay: preliminary study of trace elements contents by neutron activation analysis

    International Nuclear Information System (INIS)

    Al, As, Cu, Fe, Mn and Ti contents were analyzed for the epilithic antarctic lichen usnea antarctica, used as a biomonitors for air quality. The samples were taken in the surrounding area of the Peruvian scientific station 'Machu Picchu' on King George Island, in the Southern Shetland Archipelago (Antarctica). These elements have been assayed by neutron activation analysis (NAA). The preliminary obtained results support the hypothesis that an atmospheric circulation of chemicals exists on the assessed area and the activities developed at the different scientific stations located on this island would be a potential source of chemical pollutants for the evaluated area

  14. Vanadium determination in Perna perna mussels (Linnaeus, 1758: Mollusca, Bivalvia) by instrumental neutron activation analysis using the passive biomonitoring in the Santos coast, Brazil

    International Nuclear Information System (INIS)

    Vanadium determination present in seawater is of great importance to evaluate marine contamination from industrial sources as well as to identify health hazards since mussels and other marine organisms are used as food. Besides, this evaluation in the Santos coast, SP, Brazil, is important, since this area is impacted by industrial and urban activities and discharges from ships and boats. In a previous study, V results obtained for transplanted mussel (active biomonitoring) were presented. This study aimed the V determination by passive biomonitoring by analyzing Perna perna mussels collected in natural environment, from three sites in Sao Paulo State coast: Cocanha Beach (reference site), Ponta de Itaipu and Palmas Island. Ninety individuals of mussels were collected in each site between September/08 and July/09 during the four seasons of the year. After shell removal and sample preparation, V was determined by instrumental neutron activation analysis. For analytical quality control, the NIST Standard Reference Material SRM 1566b Oyster Tissue was analyzed and the results presented good accuracy. The V concentrations in mussels on dry mass basis varied from 0.77 ± 0.02 to 3.56 ± 0.88 mg kg-1. Statistical tests were applied to the results showing differences on V concentrations among the sampling sites and season of sample collection. (author)

  15. Tillandsia usneoides L, a biomonitor in the determination of Ce, La and Sm by neutron activation analysis in an industrial corridor in Central Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Isaac-Olive, K. [Facultad de Medicina. Universidad Autonoma del Estado de Mexico, Paseo Tollocan s/n, esq. Jesus Carranza, Toluca, 50120 Estado de Mexico (Mexico); Solis, C., E-mail: corina@fisica.unam.mx [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, 04510 Mexico DF (Mexico); Martinez-Carrillo, M.A; Andrade, E. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, 04510 Mexico DF (Mexico); Lopez, C.; Longoria, L.C. [Instituto Nacional de Investigaciones Nucleares (ININ), Salazar, 50045 Estado de Mexico (Mexico); Lucho-Constantino, C.A. [Universidad Politecnica de Pachuca, Carretera Pachuca-Cd. Sahagun, Km. 20., Hidalgo, Mexico (Mexico); Beltran-Hernandez, R.I. [Centro de Investigaciones Quimicas, Universidad Autonoma del Estado de Hidalgo. Carretera Pachuca-Tulancingo km. 4.5, 42184, Pachuca, Hidalgo (Mexico)

    2012-04-15

    The atmosphere of the Tula Industrial Corridor in Central Mexico is contaminated due to several industries including oil refining while station monitoring in this area are limited. Lanthanides are considered fingerprint of oil refinery activities, and La, Ce and Sm have been previously detected in this area using filters. The suitability of T. usneoides as a biomonitor assessing the La, Ce and Sm concentrations in Particulate Matter is evaluated by NAA. Results of both biomonitor and filters are highly correlated.

  16. Tillandsia usneoides L, a biomonitor in the determination of Ce, La and Sm by neutron activation analysis in an industrial corridor in Central Mexico

    International Nuclear Information System (INIS)

    The atmosphere of the Tula Industrial Corridor in Central Mexico is contaminated due to several industries including oil refining while station monitoring in this area are limited. Lanthanides are considered fingerprint of oil refinery activities, and La, Ce and Sm have been previously detected in this area using filters. The suitability of T. usneoides as a biomonitor assessing the La, Ce and Sm concentrations in Particulate Matter is evaluated by NAA. Results of both biomonitor and filters are highly correlated.

  17. Assessment of atmospheric deposition of heavy metals and other elements in Belgrade using the moss biomonitoring technique and neutron activation analysis

    International Nuclear Information System (INIS)

    The study aimed at assessing atmospheric deposition of heavy metals and other elements using the moss genera Brachythecium sp. (B. rutabulum and B. salebrosum) and Eurhynchium sp. (E. hians and E. striatum) collected in autumn 2004 in the urban area of Belgrade. The concentrations of 36 elements (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Mo, Sb, I, Cs, Ba, La, Ce, Sm, Tb, Dy, Hf, Ta, W, Hg, Th, U) were determined in moss and local topsoil samples by instrumental neutron activation analysis. The concentration of elements in moss positively correlated to those obtained for topsoil. High enrichment factors for As, Zn, Mo, Br, Sb, Se, Hg, and Cl, calculated to continental crust composition, gave an evidence for anthropogenic impact on urban area, mainly due to intensive vehicular traffic and fossil fuel combustion. The concentrations of elements in moss, characteristic for fossil fuel combustion, obtained in this study, were substantially lower than in the previous investigation (2000) conducted in the area of Belgrade. The level of concentrations for V, Cr, Ni, and As in moss from this study correlated to those measured for neighboring countries, and were several times higher than the base-level data from low polluted areas. The level of accumulated elements in both investigated moss genera were similar and all studied species could be combined for biomonitoring purposes in urban areas

  18. Atmospheric deposition of rare earth elements in Albania studied by the moss biomonitoring technique, neutron activation analysis and GIS technology.

    Science.gov (United States)

    Allajbeu, Sh; Yushin, N S; Qarri, F; Duliu, O G; Lazo, P; Frontasyeva, M V

    2016-07-01

    Rare earth elements (REEs) are typically conservative elements that are scarcely derived from anthropogenic sources. The mobilization of REEs in the environment requires the monitoring of these elements in environmental matrices, in which they are present at trace level. The determination of 11 REEs in carpet-forming moss species (Hypnum cupressiforme) collected from 44 sampling sites over the whole territory of the country were done by using epithermal neutron activation analysis (ENAA) at IBR-2 fast pulsed reactor in Dubna. This paper is focused on REEs (lanthanides) and Sc. Fe as typical consistent element and Th that appeared good correlations between the elements of lanthanides are included in this paper. Th, Sc, and REEs were never previously determined in the air deposition of Albania. Descriptive statistics were used for data treatment using MINITAB 17 software package. The median values of the elements under investigation were compared with those of the neighboring countries such as Bulgaria, Macedonia, Romania, and Serbia, as well as Norway which is selected as a clean area. Geographical distribution maps of the elements over the sampled territory were constructed using geographic information system (GIS) technology. Geochemical behavior of REEs in moss samples has been studied by using the ternary diagram of Sc-La-Th, Spider diagrams and multivariate analysis. It was revealed that the accumulation of REEs in current mosses is associated with the wind-blowing metal-enriched soils that is pointed out as the main emitting factor of the elements under investigation. PMID:27044293

  19. Atmospheric deposition of heavy metals around the lead and copper-zinc smelters in Baia Mare, Romania, studied by the moss biomonitoring technique, neutron activation analysis and flame atomic absorption spectrometry

    International Nuclear Information System (INIS)

    The mosses Pleurozium schreberi, Pseudoscleropodium purum and Rhytidiadelphus squarrosus were used as biomonitors to study the atmospheric deposition of metals around the lead and copper-zinc smelters in Baia Mare. Samples representing the last three years' growth of moss or its green part, collected on the ground at 28 sites located 2-17 km from the source area, were analyzed by instrumental neutron activation analysis using epithermal neutrons (ENAA) and by flame atomic absorption spectrometry (FAAS). A total of 31 elements were determined, including most of the heavy metals characteristic of emissions from this kind of industry. The observed data for Pb, As, Cu, and Cd are all high compared with those observed in other regions of Europe with similar industries, but the concentrations in moss approach regional background levels at a distance of about 8 km from the main source area. Factor analysis of the data distinguishes two industrial components, one characterized by Pb, Cu, As, and Sb, and another one by Zn and Cd. A strong crustal component including five major elements (Na, Mg, Al, Ti, Fe) and an additional number of trace elements (Sc, V, Cr, Cs, Ba, REE, Th) also appears to be derived mainly from industrial sources. The mean I value in the present material is 5 times lower than the corresponding level in moss in Norway, and also consistently lower than elsewhere in Europe, a fact which evidences the endemic character of the examined area due to iodine depletion. (author)

  20. Atmospheric deposition of heavy metals around the lead and copper-zinc smelters in Baia Mare, Romania, studied by the moss biomonitoring technique, neutron activation analysis and flame atomic absorption spectrometry

    International Nuclear Information System (INIS)

    The mosses Pleurozium schreberi, Pseudoscleropodium purum and Rhytidiadelphus squarrosus were used as biomonitors to study the atmospheric deposition of heavy metals around the lead and copper-zinc smelters in Baia Mare. Samples representing the last three year's growth of moss or its green part, collected on the ground at 28 sites located 2-17 km from the source area, were analyzed by instrumental neutron activation analysis using epithermal neutrons and by flame atomic absorption spectrometry. A total of 31 elements were determined, including most of the heavy metals characteristic of emissions from this kind industry. The observed data for Pb, As, Cu, and Cd are all high compared with those observed in other regions of Europe with similar industries, but the concentrations in moss approach regional background levels at a distance of about 8 km from the main source area. Factor analysis of the data distinguishes two industrial components, one characterized by Pb, Cu, As, and Sb, and another one by Zn and Cd. A strong crustal component including five major elements (Na, Mg, Al, Ti, Fe) and an additional number of trace elements (Sc, V, Cr, Cs, Ba, REE, Th) also appears to be derived mainly from industrial sources. The mean I value in the present material is 5 times lower than the corresponding level in moss in Norway, and also consistently lower than elsewhere in Europe, a fact which evidence the endemic character of the examined area due to iodine depletion

  1. Atmospheric Deposition of Heavy Metals around the Lead and Copper-Zinc Smelters in Baia Mare, Romania, Studied by the Moss Biomonitoring Technique, Neutron Activation Analysis and Flame Atomic Absorption Spectrometry

    CERN Document Server

    Culicov, O A; Steinnes, E; Okina, O S; Santa, Z; Todoran, R

    2002-01-01

    The mosses Pleurozium schreberi, Pseudoscleropodium purum and Rhytidiadelphus squarrosus were used as biomonitors to study the atmospheric deposition of heavy metals around the lead and copper-zinc smelters in Baia Mare. Samples representing the last three years' growth of moss or its green part, collected on the ground at 28 sites located 2-17 km from the source area, were analyzed by instrumental neutron activation analysis using epithermal neutrons and by flame atomic absorption spectrometry. A total of 31 elements were determined, including most of the heavy metals characteristic of emissions from this kind industry. The observed data for Pb, As, Cu, and Cd are all high compared with those observed in other regions of Europe with similar industries, but the concentrations in moss approach regional background levels at a distance of about 8 km from the main source area. Factor analysis of the data distinguishes two industrial components, one characterized by Pb, Cu, As, and Sb, and another one by Zn and Cd...

  2. Validation of the instrumental neutron activation analysis method for mercury analysis in hair samples used for biomonitoring of mercury environmental contamination

    International Nuclear Information System (INIS)

    Environmental mercury contamination has lately become of widespread concern in Brazil owing to gold extraction activities in the Amazon region and also to industrial activities. It is estimated that tonnes of mercury are thrown in the rivers of the Amazon region annually or are evaporated into the open air owing to the amalgamation procedure employed in gold extraction. In the present work, as pail of an IAEA Co-ordinated Research Programme (CRP), three main population groups were studied: a control group of individuals with no suspicion of contamination by mercury; a group of people living near the Billings Dam, located in one of the most heavily industrialized parts of the country, and several Indian tribes living in Xingu Park, an Indian reservation located in the Amazon region. An important part of the CRP was the validation of the analytical methodology for die analysis of total mercury in the hair samples of the population groups studied. Instrumental neutron activation analysis (INAA) was chosen for the analysis of mercury in these samples. It has the advantage of being non-destructive, which can be quite convenient when dealing with a large number of samples, which is the case in epidemiological studies. The experimental procedure consisted of irradiation of the hair samples in the IEA-R1 nuclear research reactor and measurement of the gamma radioactivity of 197Hg. For the validation of the analytical methodology, the following reference materials (RMs) were analysed: IAEA MA-A-2/TM Fish Flesh Homogenate; SHINR GBW-9101 Chinese Human Hair and the candidate RMs IAEA-085 and IAEA-086 Human Hair. The recently acquired RM BCR CRM-397 was also analysed. The accuracy and precision of the INAA method for the analysis of these RMs is discussed, as well as the applicability of the method to the analysis of mercury in the hair of the population groups studied. (author)

  3. Using devitalized moss for active biomonitoring of water pollution.

    Science.gov (United States)

    Debén, S; Fernández, J A; Carballeira, A; Aboal, J R

    2016-03-01

    This paper presents the results of an experiment carried out for the first time in situ to select a treatment to devitalize mosses for use in active biomonitoring of water pollution. Three devitalizing treatments for the aquatic moss Fontinalis antipyretica were tested (i.e. oven-drying at 100 °C, oven-drying with a 50-80-100 °C temperature ramp, and boiling in water), and the effects of these on loss of material during exposure of the transplants and on the accumulation of different heavy metals and metalloids were determined. The suitability of using devitalized samples of the terrestrial moss Sphagnum denticulatum to biomonitor aquatic environments was also tested. The structure of mosses was altered in different ways by the devitalizing treatments. Devitalization by boiling water led to significantly less loss of material (p < 0.01) than the oven-drying treatments. However, devitalization by oven-drying with a temperature ramp yielded more stable results in relation to both loss of material and accumulation of elements. With the aim of standardizing the moss bag technique, the use of F. antipyretica devitalized by oven-drying with a temperature ramp is recommended, rather than other devitalization treatments or use of S. denticulatum. PMID:26803787

  4. Active biomonitoring of magnesium and manganese using the Perna perna mussel collected in the north shore of Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    The objective of the present work was to study the active biomonitoring of magnesium and manganese in the seashore of Sao Paulo, using the Perna perna mussel , which was transplanted from an uncontaminated region to probably contaminated sites. Mussel samples acquired in the control region, a mussel farm in Cocanha beach Caraguatatuba, were exposed for three months in the study sites, in Sao Sebastiao, Ilhabela, Ilha das Palmas and Ponta de Itaipu. The mussel samples were cleaned, grinded, homogenized, lyophilized and then analyzed by instrumental neutron activation analysis, (INAA).The INAA procedure consisted in the irradiation of the samples and synthetic standards of magnesium and manganese for 10 s, under a thermal neutron flux of 6,6 x 1012 n cm-2 s-1 in the nuclear research reactor IEA-R1 of IPEN-CNEN/SP. The measurements of the gamma radioactivity of the samples and standards were done using an hyperpure semiconductor Ge detector, coupled to associated electronics. For analytical quality control of the results, the certified reference material (CRM) NIST SRM 1566b Oyster Tissue was analyzed and the results obtained indicated good agreement with the certified values. The results obtained in the mussel samples analysis indicated that the samples exposed in Ilhabela in the autumn season presented higher accumulation of magnesium (7051 ± 333 μg g-1) than the other sites. For manganese, the highest concentrations were obtained for the mussels exposed in Ilha das Palmas in springtime, with 28.5 ± 0.8 μg g-1. It was concluded that it is possible to biomonitor magnesium and manganese by means of the analysis of Perna perna mussels. (author)

  5. Active biomonitoring of palladium, platinum, and rhodium emissions from road traffic using transplanted moss.

    Science.gov (United States)

    Suoranta, Terhi; Niemelä, Matti; Poikolainen, Jarmo; Piispanen, Juha; Bokhari, Syed Nadeem Hussain; Meisel, Thomas; Perämäki, Paavo

    2016-08-01

    The use of transplanted moss (Pleurozium schreberi) in active biomonitoring of traffic-related emissions of Pd, Pt, and Rh was studied. Moss mats were transplanted to three locations along highway E75 (in Oulu, Finland) at three different distances from the highway. Five samples were collected from a background site after the same exposure period. Mass fractions of Pd, Pt, and Rh as well as mass fractions of 18 other elements were determined in these samples. The results indicated that P. schreberi is well suited for active biomonitoring of Pd, Pt, and Rh. Mass fractions above the background values were observed in the samples exposed to traffic-related emissions. When the results were compared with those of the other elements, high correlations of Pd, Pt, and Rh with commonly traffic-related elements (e.g., Cu, Ni, Sb, Zn, etc.) were found. It was also found that the amounts of Pd, Pt, and Rh in moss samples decreased when the distance to the highway increased. This trend gives evidence for the suitability of P. schreberi for active biomonitoring of Pd, Pt, and Rh. Furthermore, it can be concluded that the mass fractions determined in this study provide valuable evidence about the current state of Pd, Pt, and Rh emissions in Oulu, Finland. PMID:27189454

  6. Metal dispersion and transportational activities using food crops as biomonitors.

    Science.gov (United States)

    Ward, N I; Savage, J M

    1994-05-23

    The multielement (Al, Ca, Cd, Ce, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Si, and Zn) levels of various common vegetables (bean, broccoli, cabbage, cauliflower, lettuce, marrow, onion, parsnip, spinach, sprouts, sweet corn, and tomato); fruits (grape and strawberry); herbs (garlic, lemon balm, marjoram, mint, rosemary and tarragon); local pasture species and surface soils collected from a commercial garden centre located within a distance of 30 m of the London Orbital Motorway (M25) is presented. Comparative values are given from a background area, namely a domestic garden located in the North Yorkshire Dales National Park area. Analysis was undertaken by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma-source mass spectrometry (ICP-MS) with quality control assessment using four international biological reference materials; BCR:CRM 62 Olive Leaves, NIST 1575 Pine Needles, NIST 1573 Tomato Leaves, and NIST 1572 Citrus Leaves. Inter-analytical method comparison is given using two methods of ICP-MS; namely conventional pneumatic nebulisation of sample solution, and direct solids analysis by laser ablation; and neutron activation analysis methods (NAA). For the elements listed there is a good precision obtained by ICP-MS and NAA. In particular levels of herbs > vegetables > cereals > fruits. Measured values are in good agreement with reported literature values. The lowest Pb values are for marrow, lettuce, tomato and sweet corn samples (approximately 0.001-0.021 microgram/g). 'Green' leaf material levels were approximately 0.02-0.10 microgram/g (i.e. sprouts and cabbage). Root vegetables contain higher levels, approximately 0.02-0.125 microgram/g (especially carrot), reflecting possible metal uptake from soil. The highest vegetable Pb values are for leek and onion (approximately 0.35 microgram/g). Background values are also provided for nineteen elements (Al, As, B, Ba, Br, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, V, and Zn

  7. Active neutron instrumentation

    International Nuclear Information System (INIS)

    An introduction to neutron interactions in tissue and a discussion of pertinent nuetron cross-sections will be given. A brief description of the statistics of energy deposition due to interactions of neutron secondaries in tissue equivalent media is presented. Present and past techniques for measurement of neutron radiation fields are given with advantages and disadvantages in the light of legal limits and proposed changes in those requirements. Neutron dose measuring devices, such as the tissue equivalent proportional counter (TEPC) developed by Rossi, are discussed with emphasis on their response in varying neutron energy spectra. Techniques for determining neutron quality factors from TEPC response functions are discussed along with implications of possible new definitions of quality factor. A brief description of high-resolution spectrometry systems, which use hydrogen, methane and He-3 fill gases, is given with discussion of their limitations. Low resolution systems, such as multisphere spectrometers and activation foils, are also presented

  8. Neutron Activation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, William R.

    1968-01-01

    In activation analysis, a sample of an unknown material is first irradiated (activated) with nuclear particles. In practice these nuclear particles are almost always neutrons. The success of activation analysis depends upon nuclear reactions which are completely independent of an atom's chemical associations. The value of activation analysis as a research tool was recognized almost immediately upon the discovery of artificial radioactivity. This book discusses activation analysis experiments, applications and technical considerations.

  9. Environmental lichenology: Biomonitoring of trace element air pollution

    International Nuclear Information System (INIS)

    The review of application of lichens and mosses as biomonitors of air pollution have been presented. The neutron activation analysis and atomic absorption spectroscopy have been used for trace element content determination in lichens and mosses taken from different regions of Europe

  10. Isotopic neutron sources for neutron activation analysis

    International Nuclear Information System (INIS)

    This User's Manual is an attempt to provide for teaching and training purposes, a series of well thought out demonstrative experiments in neutron activation analysis based on the utilization of an isotopic neutron source. In some cases, these ideas can be applied to solve practical analytical problems. 19 refs, figs and tabs

  11. SLOWPOKE: neutron activation analysis

    International Nuclear Information System (INIS)

    Neutron activation analysis permits the non-destructive determination of trace elements in crude oil and its derivatives at high sensitivity (up to 10-9 g/g) and good precision. This article consists of a quick survey of the method followed by an illustration based on the results of recent work at the SLOWPOKE reactor laboratory at the Ecole Polytechnique

  12. The ESA Topical Team 'Biomonitors': Monitoring for the protection of environments from human activities

    Science.gov (United States)

    Rettberg, P.; Esa Tt Biomonitors

    The overall aim of the ESA Topical Team Biomonitors was to identify and summarize ongoing and planned ground based biotechnological research activities on environmental monitoring that will also become important in space research within the ESA Microgravity Applications Promotion Program Monitoring the environment for compounds and factors of concern plays an important role in defining and managing the risks to environments and artificial ecosystems on other planets resulting from chemical and biological contaminations but also gains increasing attention for a variety of terrestrial applications Especially the development of biosensors and the identification of biomarkers for the qualitative and or quantitative registration of deleterious effects is a promising approach for new tools complementary to currently available physical and chemical monitoring techniques Another very important field of concern was the fast identification and assessment of the microbial bioburden On one hand this is necessary for the long-term securing of human health and performance in a confined environment like the ISS or in a future extraterrestrial habitat On the other hand this is necessary for the development and application of adequate cleaning and sterilization measures of spacecraft for planetary protection reasons especially for already scheduled lander missions to Mars Acknowledgements The ESA Topical Team Biomonitors was financed by ESTEC Contract Nr 137989 99 NL JS The authors thank R Binot for fruitful discussions on the future of biotechnology in

  13. Neutron production, shielding and activation

    International Nuclear Information System (INIS)

    This chapter contains information on neutron cross-sections, production, spectra and yields; detection and detectors; shielding with various materials, particularly with ordinary concrete; and neutron activation products of interest to health physicists. Neutron energy terminology as well as neutron energy spectrum calculations are included

  14. Educational activities for neutron sciences

    International Nuclear Information System (INIS)

    Since now we have several world-leading neutron science facilities in Japan, enlightenment activities for introducing neutron sciences, for example, to young people is an indispensable issue. Hereafter, we will report present status of the activities based on collaborations between universities and neutron facilities. A few suggestions for future educational activity of JSNS are also shown. (author)

  15. Blood biomonitoring of metals in subjects living near abandoned mining and active industrial areas.

    Science.gov (United States)

    Madeddu, Roberto; Tolu, Paola; Asara, Yolande; Farace, Cristiano; Forte, Giovanni; Bocca, Beatrice

    2013-07-01

    A human blood biomonitoring campaign to detect the environmental exposure to metals (Cd, Cu, Cr, Mn, Pb and Zn) in 265 subjects was performed in the South-Western part of Sardinia (an Italian island) that is a particular area with a great history of coal and metal mining (Pb/Zn mainly) activities and large industrial structures (as metallurgy). Subjects living near the industrial plant area had geometric means (GM) of blood Cd (0.79 μg/l), Cu (971 μg/l), Mn (12.2 μg/l), and Pb (55.7 μg/l) significantly higher than controls (Cd, 0.47 μg/l; Cu, 900 μg/l; Mn 9.98 μg/l; Pb, 26.5 μg/l) and than people living nearby the past mining sites. Subjects living next to one dismissed mine were statistically higher in blood Cu (GM, 1,022 μg/l) and Pb (GM, 41.4 μg/l) concentrations than controls. No differences were observed in people living in the different mining sites, and this might be related to the decennial disclosure of mines and the adoption of environmental remediation programmes. Some interindividual variables influenced blood biomonitoring data, as smoke and age for Cd, gender for Cu, age, sex and alcohol for Pb, and age for Zn. Moreover, blood metal levels of the whole population were similar to reference values representative of the Sardinian population and acceptably safe according to currently available health guidelines. PMID:23229279

  16. Lichens as biomonitors at indoor environments of primary schools

    International Nuclear Information System (INIS)

    A biomonitoring study, using transplanted lichens Flavoparmelia caperata, was conducted to assess the indoor air quality in primary schools in urban (Lisbon) and rural (Ponte de Sor) Portuguese sites. The lichens exposure period occurred between April and June 2010 and two types of environments of the primary schools were studied: classrooms and outdoor/courtyard. Afterwards, the lichen samples were processed and analyzed by instrumental neutron activation analysis (INAA) to assess a total of 20 chemical elements. Accumulated elements in the exposed lichens were assessed and enrichment factors (EF) were determined. Indoor and outdoor biomonitoring results were compared to evaluate how biomonitors (as lichens) react at indoor environments and to assess the type of pollutants that are prevalent in those environments. (author)

  17. Reference neutron activation library

    International Nuclear Information System (INIS)

    Many scientific endeavors require accurate nuclear data. Examples include studies of environmental protection connected with the running of a nuclear installation, the conceptual designs of fusion energy producing devices, astrophysics and the production of medical isotopes. In response to this need, many national and international data libraries have evolved over the years. Initially nuclear data work concentrated on materials relevant to the commercial power industry which is based on the fission of actinides, but recently the topic of activation has become of increasing importance. Activation of materials occurs in fission devices, but is generally overshadowed by the primary fission process. In fusion devices, high energy (14 MeV) neutrons produced in the D-T fusion reaction cause activation of the structure, and (with the exception of the tritium fuel) is the dominant source of activity. Astrophysics requires cross-sections (generally describing neutron capture) or its studies of nucleosynthesis. Many analytical techniques require activation analysis. For example, borehole logging uses the detection of gamma rays from irradiated materials to determine the various components of rocks. To provide data for these applications, various specialized data libraries have been produced. The most comprehensive of these have been developed for fusion studies, since it has been appreciated that impurities are of the greatest importance in determining the overall activity, and thus data on all elements are required. These libraries contain information on a wide range of reactions: (n,γ), (n,2n), (n,α), (n,p), (n,d), (n,t), (n,3He)and (n,n')over the energy range from 10-5 eV to 15 or 20 MeV. It should be noted that the production of various isomeric states have to be treated in detail in these libraries,and that the range of targets must include long-lived radioactive nuclides in addition to stable nuclides. These comprehensive libraries thus contain almost all the

  18. Applications of neutron activation spectroscopy

    CERN Document Server

    Silarski, M

    2013-01-01

    Since the discovery in 1932, neutrons became a basis of many methods used not only in research, but also in industry and engineering. Among others, the exceptional role in the modern nuclear engineering is played by the neutron activation spectroscopy, based on the interaction of neutron flux with atomic nuclei. In this article we shortly describe application of this method in medicine and detection of hazardous substances.

  19. Neutron activation analysis of coins

    International Nuclear Information System (INIS)

    Activation analysis was applied to the study of coins using 14MeV neutrons produced by an accelerator for the determination of oxygen and neutrons emitted from a 252Cf source for the determination of the other elements (Au, Ag, Cu, As etc...). The advantages of this technique are presented

  20. Application of neutron activation analysis

    International Nuclear Information System (INIS)

    The physical basis and analytical possibilities of neutron activation analysis have been performed. The number of applications in material engineering, geology, cosmology, oncology, criminology, biology, agriculture, environment protection, archaeology, history of art and especially in chemical analysis have been presented. The place of the method among other methods of inorganic quantitative chemical analysis for trace elements determination has been discussed

  1. Neutron activation analysis in Bulgaria

    International Nuclear Information System (INIS)

    The development of instrumental neutron activation analysis (INAA) as a routine method started in 1960 with bringing into use of the experimental nuclear reactor 2 MW -IRT-2000. For the purposes of INAA the vertical channels were used. The neutron flux vary from 1 to 6x1012n/cm2s, with Cd ratio for gold of about 4,4. In one of the channels the neutron flux is additionally thermalised with grafite, in others - a pneumatic double-tube rabbit system is installed. One of the irradiation positions is equiped with 1 mm Cd shield constantly. With the pressure of the working gas (air) of 2 bar the transport time in one direction is 2,5 sec. Because of lack of special system for uniform irradiation an accuracy of 3% can be reached by use of iron monitors for long irradiations and copper monitors for use in the rabbit system. Two neutron generators are also working but the application of 14 MeV neutrons for INAA is still quite limited. The most developed are the applications of INAA in the fields of geology and paedology, medicine and biology, environment and pollution, archaeology, metallurgy, metrology and hydrology, criminology

  2. Activation analysis with reactor neutrons

    International Nuclear Information System (INIS)

    The potentialities of neutron as an analytical probe are indicated, pointing out the need for development of other approaches, besides the conventional activation method. Development of instrumental approach to activation and applications, carried out at Analytical Chemistry Division are outlined. The role of, and the need for, the development and application of mathematical methods in enhancing the information content, and in turn the interpretation of the analytical results, is demonstrated. (author)

  3. Advances on the study of air pollution in Cordoba by neutron activation analysis

    International Nuclear Information System (INIS)

    Air pollution biomonitoring has been carried out in an area of 160.000 km2 by neutron activation analysis of lichen samples (Usnea sp. and Ramalina ecklonii) in the framework of a Co-ordinated Research Programme of the IAEA and an ARCAL Technical Co-operation Project. The samples were irradiated in the RA-3 reactor and after a decay time of 6, 12 and 30 days, 24 elements (As, Ba, Br, Ce, Co, Cr, Cs, Eu, Fe, Hf, La, Lu, Na, Nd, Rb, Sb, Sc, Sm, Ta, Tb, Th, U and Zn) were determined by gamma spectrometry. (author)

  4. Analysis by neutron activation in moss samples for the determination of Cr, Se, As and Hg

    International Nuclear Information System (INIS)

    This research work, presents a study of environmental monitoring in the Metropolitan Area of Toluca Valley using as bio-monitors to the mosses (bryophytes) native of different sites, analyzing the concentrations of As, Cr, Hg and Se, present in its structure. The analysis technique used to identify and to quantify to these elements was the Analysis by Neutron Activation, a nuclear analytic technique that allowed determining the concentrations at track level for its great versatility. Likewise the morphological study of the bryophyte Leskea angustata is presented by scanning electron microscopy. (Author)

  5. Study of air pollution in Chile using biomonitors

    International Nuclear Information System (INIS)

    A project has been undertaken within the framework of a Co-ordinated Research Programme (CRP) supported by the International Atomic Energy Agency (IAEA) to carry out a long term study on atmospheric air pollution in Chile using biomonitors. The present project aims at the selection of appropriate plants and other indicators for monitoring of air pollution in several cities and rural areas in Chile. Nuclear analytical techniques, in particular neutron activation analysis (NAA) will be used complemented by AAS for the analysis of selected elements and to determine the sources of pollutants and the applicability of biomonitors to study air pollution in large areas, using indicators either naturally grown or artificially introduced to the region under examination. (author)

  6. Atmospheric deposition of trace elements around Ulan Bator city studied by moss and lichen biomonitoring technique and INAA

    International Nuclear Information System (INIS)

    For the first time the moss and lichen biomonitoring technique has been applied to air pollution in Mongolia (Ulan-Bator, the capital city). INAA at the IBR-2 reactor has made it possible to determine the content of 35 elements in moss and lichen biomonitors. Samples collected at sites located 10-15 km from the center of Ulan-Bator were analyzed by Instrumental Neutron Activation Analysis (INAA) using epithermal neutrons. The mosses (Rhytidium rugosum, Thuidium abietinum, Entodon concinnus) and lichens (Cladonia stellaris, Parmelia separata) were used to study the atmospheric deposition of trace elements. It was shown that the suggested types of mosses could be used as suitable biomonitors to estimate the concentration levels of heavy metals and trace elements in Ulan-Bator atmospheric deposition. The results are compared to the data of atmospheric deposition of some European countries

  7. Atmospheric Deposition of Trace Elements Around Ulan-Bator City Studied by Moss and Lichen Biomonitoring Technique and INAA

    CERN Document Server

    Ganbold, G; Gundorina, S F; Frontasyeva, M V; Ostrovnaya, T M; Pavlov, S S; Tsendeekhuu, T

    2005-01-01

    For the first time the moss and lichen biomonitoring technique has been applied to air pollution in Mongolia (Ulan-Bator, the capital city). INAA at the IBR-2 reactor has made it possible to determine the content of 35 elements in moss and lichen biomonitors. Samples collected at sites located 10-15 km from the center of Ulan-Bator were analyzed by Instrumental Neutron Activation Analysis (INAA) using epithermal neutrons. The mosses (\\textit{Rhytidium rugosum}, \\textit{Thuidium abietinum}, \\textit{Entodon concinnus}) and lichens (\\textit{Cladonia stellaris}, \\textit{Parmelia separata}) were used to study the atmospheric deposition of trace elements. It was shown that the suggested types of mosses could be used as suitable biomonitors to estimate the concentration levels of heavy metals and trace elements in Ulan-Bator atmospheric deposition. The results are compared to the data of atmospheric deposition of some European countries.

  8. Neutron activation spectrometry and neutron activation analysis in analytical geochemistry

    International Nuclear Information System (INIS)

    The present report is to show the geochemists who are interested in neutron activation spectrometry (NAS) and neutron activation analysis (NAA) which analytical possibilities these methods offer him. As a review of these analytical possibilities, a lieterature compolation is given which is subdivided into two groups: 1) rock (basic, intermediary, acid, sediments, soils and nuds, diverse minerals, tectites, meteorites and lunar material). 2) ore (Al, Au, Be, Cr, Cu, Mn, Mo, Fe, Pb, Pt, Sn, Ti, W, Zn, Zr, U and phosphate ore, polymetallic ores, fluorite, monazite and diverse ores). The applied methods as well as the determinable elements in the given materials can be got from the tables. On the whole, the literature evaluation carried out makes it clear that neutron activation spectrometry is a very useful multi-element method for the analysis of rocks. The analysis of ores, however, is subjected to great limitations. As rock analysis is very frequently of importance in prospecting for ore deposits, the NAS proves to be extremely useful for this very field of application. (orig./LH)

  9. Neutron activations at the neutron facility of TU-Dresden

    Energy Technology Data Exchange (ETDEWEB)

    Domula, Alexander; Zuber, Kai [TU Dresden, Institut fuer Kern- und Teilchenphysik, 01069 Dresden (Germany); Gehre, Daniel [TU Dresden, Institut fuer Kern- und Teilchenphysik, 01069 Dresden (Germany); FZD, Institut fuer Strahlenphysik, 01314 Dresden (Germany); Klix, Axel [KIT, Institut fuer Neutronenphysik und Reaktortechnik, 76344 Eggenstein-Leopoldshafen (Germany)

    2010-07-01

    The Technical University of Dresden (TUD) operates at the Forschungszentrum Dresden-Rossendorf (FZD) a 14 MeV Neutron Generator (NG) with fast, mono energetic neutrons from the T(d,{alpha})n reaction and 2.5 MeV neutrons from the D(d,x)n reaction. Since its commissioning in 2004 the NG is involved in the validation of European Activation File and mockup experiments for validation of neutron transport data in collaborations with FZK/KIT, PTB, ENEA, JAEA, Osaka University and University Vienna. Cross section measurements have been limited to long living isotopes. An automated sample changer is currently set up in order to extend the capabilities to radioisotopes with half-lives in the range from seconds to a few minutes. The general layout of the neutron facility is described. First example activations for GERDA and SNO+ have been made and are presented here.

  10. The Atomic Fingerprint: Neutron Activation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Keisch, Bernard [Carnegie-Mellon University

    1972-01-01

    The nuclei of atoms are stable only when they contain certain numbers of neutrons and protons. Since nuclei can absorb additional neutrons, which in many cases results in the conversion of a stable nucleus to a radioactive one, neutron activation analysis is possible.

  11. Instrumentation in neutron activation analysis

    International Nuclear Information System (INIS)

    The rise of neutron activation analysis (NAA) as a tool in geochemical research has parallelled advances in detector, multi-channel analyzer, and computer technology. Micro-computers are now being integrated into NAA systems, and gamma-ray spectrometer instrumentation is evolving towards direct-reading systems. The investigator is faced with a wide range of possibilities and choices when equipping or re-equipping a laboratory. The geoscientist is provided with an overview of the available instrumentation and what soon may be feasible. (L.L.)

  12. Active biomonitoring in freshwater environments: early warning signals from biomarkers in assessing biological effects of diffuse sources of pollutants

    Science.gov (United States)

    Wepener, V.; van Vuren, J. H. J.; Chatiza, F. P.; Mbizi, Z.; Slabbert, L.; Masola, B.

    Effluents are a main source of direct and continuous input of pollutants in aquatic ecosystems. Relating observed effects to specific pollutants or even classes of pollutants remains a very difficult task due to the usually unknown, complex and often highly variable composition of effluents. It is recognized that toxicants interfere with organism integrity at the biochemical level and give rise to effects at the individual level and is manifested in reduced ecologically relevant characteristics such as growth, reproduction and survival, and ultimately at the ecosystem level. By integrating multiple endpoints at different ecologically relevant levels of organization within one test organism, it should be possible to gain understanding in how different levels of organization within this organism respond to toxic exposure and how responses at these different levels are interrelated. This paper presents results from a field study in the Rietvlei Wetland system, Gauteng, South Africa using the freshwater mollusk ( Melanoides tuberculata) and freshwater fish ( Oreochromis mossambicus) as bioindicator organisms. Active biomonitoring (ABM) exposures were conducted where organisms were exposed for 28 days in an effluent dominated river during high flow conditions in April 2003. The river receives effluent from a wastewater treatment plant and an industrial complex, so that up to 75% of the total flow of the river is effluent-based. Effects of field exposure were determined using cellular biomarkers e.g. DNA damage, HSP 70, metallothionein, acetylcholine esterase, lactate dehydrogenase and ethoxyresorufin-o-deethylase activity. The results clearly indicate that although the traditional mortality-based whole effluent toxicity testing did not indicate any toxicity, the in situ exposed organisms were stressed. A multivariate statistical approach was particularly useful for integrating the biomarker responses and highlighting sites at which more detailed analysis of chemical

  13. Recent activities on neutron beam utilization

    International Nuclear Information System (INIS)

    In Japan, the utilization of neutron beam brought out in research reactors had mainly been carried out in KUR of Kyoto University and JRR-2 of Japan Atomic Energy Research Institute (JAERI) in the fields of neutron scattering experiment, neutron radiography, neutron induced prompt-gamma ray analysis, medical and biological irradiation and so on. After the completion of upgrading work of JRR-3 in JAERI in 1990 (JRR-3M), the quality and quantity for the neutron beam experiments are extremely improved by means of its high intensity of neutron flux and high signal-to-noise ratio of cold and thermal neutron beams at more than twenty neutron beam ports. Especially, the cold neutron beam has brought the field of the utilization expanded and the neutron guide tubes have increased the number of neutron beam facilities as if there are three research reactors. These facilities induced to more active use of research reactors and increased the researchers in the many fields. At present, research reactors are utilized widely in various fields of not only nuclear researches but also non-nuclear researches and industrial uses. The JRR-3M has been operated only for about three years, however, interesting results have already been obtained using cold and thermal neutron beams. The current status of the neutron beam utilization using the research reactors in JAERI is reported and also several research topics obtained at JRR-3M are introduced in this presentation. (author)

  14. Active biomonitoring of airborne fluoride near an HF producing factory using standardised grass cultures

    Science.gov (United States)

    Franzaring, J.; Klumpp, A.; Fangmeier, A.

    In order to study the pollution gradient in the vicinity of an HF producing factory, a biomonitoring programme was performed employing VDI standardised grass cultures. Specimen plants of Lolium multiflorum cv. Lema were exposed at 11 sites over five monthly periods and the biomass produced was used for subsequent F-analyses. Meteorological data from the study region confirmed that wind direction accounted for changes in the pollution pattern over periods of time. Fluoride concentrations in the grass cultures, however, were unrelated to temperature and precipitation sums during the exposures. The biomass production of the grass cultures proved to be unrelated to these parameters as well but, with the enhanced growth of the plants, the fluoride concentrations were lower due to the dilution of the element with higher biomass accumulation. Because the contribution of particulate fluoride was unknown, both the washed grass cultures and the washing water were analysed in order to determine the amount of external fluoride. Washing reduced the fluoride concentrations by 22% on average, indicating that most of the element was internal fluoride stemming from stomatal uptake. Larger amounts of fluoride, however, could be washed off from grass cultures exposed at sites close to the factory indicating that dust emissions played a greater role at these locations. Because particulate emissions were supposed to arise from CaF 2 and the waste-product anhydrite, grass cultures were also analysed for calcium and sulphur. While calcium concentrations were generally high but unrelated to fluoride, sulphur concentrations showed a slight relationship to the F-concentrations determined in the unwashed plants. Latter findings indicate the co-deposition of the two elements as surface bound, external loads, but bioindication could not clarify to what extent both elements were partitioned in the gas-to-particle phase. We therefore recommend using the grass culture method in air quality

  15. Neutron fluence spectrometry using disk activation

    International Nuclear Information System (INIS)

    A simple and robust detector for spectrometry of environmental neutrons has been developed. The technique is based on neutron activation of a series of different metal disks followed by low-level gamma-ray spectrometry of the activated disks and subsequent neutron spectrum unfolding. The technique is similar to foil activation but here the applied neutron fluence rates are much lower than usually in the case of foil activation. The detector has been tested in quasi mono-energetic neutron fields with fluence rates in the order of 1000-10000 cm-2 s-1, where the obtained spectra showed good agreement with spectra measured using a Bonner sphere spectrometer. The detector has also been tested using an AmBe source and at a neutron fluence rate of about 40 cm-2 s-1, again, a good agreement with the assumed spectrum was achieved

  16. Fast neutron activation dosimetry with TLDS

    Energy Technology Data Exchange (ETDEWEB)

    Pearson, D.W.; Moran, P.R.

    1975-01-01

    Fast neutron activation using threshold reactions is the only neutron dosimetry method which offers complete discrimination against gamma-rays and preserves some information about the neutron energy. Conventional activation foil technique requires sensitive radiation detectors to count the decay of the neutron induced activity. For extensive measurements at low neutron fluences, vast outlays of counting equipment are required. TL dosimeters are inexpensive, extremely sensitive radiation detectors. The work of Mayhugh et al. (Proc. Third Int. Conf. on Luminescence Dosimetry, Riso Report 249, 1040, (1971)) showed that CaSO/sub 4/: DyTLDs could be used to measure the integrated dose from the decay of the radioactivity produced in the dosimeters by exposure to thermal neutrons. This neatly combines the activation detector and counter functions in one solid state device. This work has been expanded to fast neutron exposures and other TL phosphors. The reactions /sup 19/F(n, 2n)/sup 18/F, /sup 32/S(n,p)/sup 32/P, /sup 24/Mg(n,p)/sup 24/, and /sup 64/Zn(n,p)/sup 64/Cu were found useful for fast neutron activation in commercial TLDs. As each TLD is its own integrating decay particle counter, many activation measurements can be made at the same time. The subsequent readings of the TL signals can be done serially after the induced radioactivity has decayed, using only one TL reader. The neutron detection sensitivity is limited mainly by the number statistics of the neutron activations. The precision of the neutron measurement is within a factor of two of conventional foil activation for comparable mass detectors. Commercially available TLDs can measure neutron fluences of 10/sup 9/n/cm/sup 2/ with 10 percent precision.

  17. Fast neutron activation dosimetry with TLDS

    International Nuclear Information System (INIS)

    Fast neutron activation using threshold reactions is the only neutron dosimetry method which offers complete discrimination against gamma-rays and preserves some information about the neutron energy. Conventional activation foil technique requires sensitive radiation detectors to count the decay of the neutron induced activity. For extensive measurements at low neutron fluences, vast outlays of counting equipment are required. TL dosimeters are inexpensive, extremely sensitive radiation detectors. The work of Mayhugh et al. (Proc. Third Int. Conf. on Luminescence Dosimetry, Riso Report 249, 1040, (1971)) showed that CaSO4: DyTLDs could be used to measure the integrated dose from the decay of the radioactivity produced in the dosimeters by exposure to thermal neutrons. This neatly combines the activation detector and counter functions in one solid state device. This work has been expanded to fast neutron exposures and other TL phosphors. The reactions 19F(n, 2n)18F, 32S(n,p)32P, 24Mg(n,p)24, and 64Zn(n,p)64Cu were found useful for fast neutron activation in commercial TLDs. As each TLD is its own integrating decay particle counter, many activation measurements can be made at the same time. The subsequent readings of the TL signals can be done serially after the induced radioactivity has decayed, using only one TL reader. The neutron detection sensitivity is limited mainly by the number statistics of the neutron activations. The precision of the neutron measurement is within a factor of two of conventional foil activation for comparable mass detectors. Commercially available TLDs can measure neutron fluences of 109n/cm2 with 10 percent precision

  18. DD neutron yield diagnosis by indium activation

    International Nuclear Information System (INIS)

    The measurement of DD neutron yield by activation is presented. This method is based on the inelastic scattering reaction of 115In with DD neutron, and the activated γ spectrum is counted by HPGe detector. The relation between the counts of detected y rays and the neutron yield is analyzed. The optimal thickness of sample is given by Monte Carlo simulation, which is 1 cm. The entire counting system has been calibrated on the K-400 accelerator. The result shows that the DD neutron measurement by indium activation can be used in the ICF experiment when the neutron yield is above 2 × 109. The total error of the system is below 10% in this condition. The total error will reduce when the neutron yield is larger. (authors)

  19. Manually controlled neutron-activation system

    Science.gov (United States)

    Johns, R. A.; Carothers, G. A.

    1982-01-01

    A manually controlled neutron activation system, the Manual Reactor Activation System, was designed and built and has been operating at one of the Savannah River Plant's production reactors. With this system, samples can be irradiated for up to 24 hours and pneumatically transferred to a shielded repository for decay until their activity is low enough for them to be handled at a radiobench. The Manual Reactor Activation System was built to provide neutron activation of solid waste forms for the Alternative Waste Forms Leach Testing Program. Neutron activation of the bulk sample prior to leaching permits sensitive multielement radiometric analyses of the leachates.

  20. Assessment of air quality in Mangabeiras' Park, Belo Horizonte, Brazil, using epiphytic lichens as biomonitor

    International Nuclear Information System (INIS)

    Biomonitoring has been used as an alternative method to study the air pollution in several countries. The lichen, or lichenized fungi, is one of the most efficient on air pollution biomonitoring among the biomonitors. However, in Brazil, systematic use of lichens as biomonitors of environmental pollution is quite rare. In order to make an assessment of the air quality of the Mangabeiras' Park, this study was conducted by measuring the concentration of elements accumulated in the lichen thallus. This park, located in Belo Horizonte (Minas Gerais, Brazil), is the greatest green area in the city, and an apparent region of non polluted air. During the development of the study, epiphytic lichens of several species were collected using a steel stainless knife, taking samples of similar sizes from 1.5 m from the soil. The lichens selection was based on morphological similarities, such as color and type of the thallus. The elemental concentration determination was carried out applying the neutron activation technique, k0-standardization method, using the TRIGA Mark I IPR-R1 research reactor located at CDTN/CNEN. The lichen samples presented expressive concentrations of Ba, Fe, K, Na and Zn. However, the presence of other characteristic soil elements from the region, such as As, Th and U, suggests the influence of the mining activity area, located in the surroundings. (author)

  1. Biomonitoring of air pollution through trace element analysis

    International Nuclear Information System (INIS)

    Research work is currently going on to determine the suitability in the use of local lichen species for biomonitoring air pollution in Ghana. The study areas being investigated are the gold-mining areas situated in the Moist Evergreen and Semi-Deciduous forests in Ghana. The nuclear analytical techniques being used in this work are instrumental neutron activation analysis and tube-excited x-ray fluorescence spectrometry. The present report covers results of quality control exercise carried out to validate the quantitative methods being used. This includes our participation in an intercomparison exercise carried out among participants of the IAEA coordinated research project. The samples analyzed were two lichen samples from two completely different areas using neutron activation analysis. Only short- and medium-lived irradiations were carried out. Satisfactory results were obtained for most of the elements identified and quantified. (author)

  2. Lichens as biomonitors with special reference to Antarctica

    International Nuclear Information System (INIS)

    Lichens are effective biomonitors of metal deposition. Lichens are slow growing and assimilate metals at a rapid rate but release them at a low rate. Metal concentrations in lichen thalli have been shown to correlate with atmospheric levels. Lichens have been first used as bioaccumulative indicators in relation to point emission sources. Lichens have also been used to assess deposition patterns and heavy metal burdens for larger scale monitoring purposes. There are two problems to be kept in mind if lichens are to be effectively used as biomonitors. The first one is concerned with the chemical analyses. Results are more useful when background elemental levels are obtained. The choice of analytical method will depend on the purpose of the respective survey. Instrumental neutron activation analysis (INAA), atomic absorption spectrometry (AAS), Inductively coupled plasma emission spectrometry (ICP-ES) and epithermal neutron activation analysis (ENAA) are among the most commonly used methods. The second problem arises from the variability of lichens. Sources of variability include intra-individual variation, intra-species variation and variation due to microhabitat, locality or edaphic factors. Apart from individual variation, many of these sources of variation can be overcome by careful and thoughtful sampling and analysis of the selected species. Lichens and mosses are the only vegetation in Antarctica. The absence of air pollution in Antarctica suggests that lichens can be used as biomonitors of pollution at small scales around research bases. However, the unpolluted Antarctic environment presents opportunity for baseline studies on heavy metal bioaccumulation. Bioaccumulation in Antarctic lichens can allow a larger (global) scale insight into the airborne heavy metal circulation and deposition. Both high precision analytical methods and biological studies will be needed. (author)

  3. Neutron activation analysis - NAA: studies of environmental pollution in Steel Valley region, Brazil

    International Nuclear Information System (INIS)

    The Steel Valley region in Minas Gerais State, Brazil, receives intense waste from anthropogenic activities: industries (steel, cellulose, ore mining); untreated domestic; sewage and agricultural discharges. This work presents results obtained from analysis of air quality (Ipatinga, Santana do Paraiso, Coronel Fabriciano Timoteo and Marlieria cities) and by the Piracicaba River (surface water, border sediment, and fish muscle - Acara (Geophagus Brasiliensis). Concentrations of Al, Mn, V, As, Br, K, La, Na, Ce, Co, Cr, Cs, Fe, Hg, Rb, Sc, Sm, Th and Zn were determined for Neutron Activation Analysis, NAA. High concentrations were found in sediment and water (Cr, Fe, Co, Zn, As, Al, Mn, V) and in fish muscle (As, Cr, Hg). Results were compared to the maximum limits for metal set by 357/2005 of the National Environmental Council (CONAMA). Terrestrial epiphytic community samples have been used as biomonitor of air pollution. The samples were collected in trees Oiti (Licania tomentosa) and Angico (Piptadenia rigida), very common in studied region. The samples were collected in 17 points and two weather stations: January (rainy) and June (dried) of 2007. The results indicate high concentrations of the elements Al, Au, Co, Cr, Cu, Fe, Hg, Mn, Mg, Zn, V and Th when compared with the values cited in the literature. The biomonitor used in this work, terrestrial epiphytic community, showed an excellent capacity for metals retention by atmospheric contamination. (author)

  4. Active moss biomonitoring of small-scale spatial distribution of airborne major and trace elements in the Belgrade urban area.

    Science.gov (United States)

    Vuković, Gordana; Aničić Urošević, Mira; Razumenić, Ivana; Goryainova, Zoya; Frontasyeva, Marina; Tomašević, Milica; Popović, Aleksandar

    2013-08-01

    In urban environments, human exposure to air pollutants is expected to be significantly increased, especially near busy traffic streets, street canyons, tunnels, etc. where urban topography and microclimate may additionally cause poor air conditions giving rise to pollution hotspots. As a practical and cost-effective approach, active moss biomonitoring survey of some major and trace element air pollution was performed in the Belgrade street canyons and city tunnel in 2011 with the aim to evaluate possibility of using Sphagnum girgensohnii moss bags for investigation of the small-scale vertical and horizontal distribution patterns of the elements. In five street canyons, the moss bags were hung at heights of about 4, 8 and 16 m, during 10 weeks, and also, for the same time, the moss bags were exposed in the tunnel, in front of and out of it. After the exposure period, the concentrations of Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr, V and Zn in the moss were determined by inductively coupled plasma optical emission spectrometry. According to the results, in all street canyons, the vertical distribution patterns of the moss elements concentration (Al, Ba, Co, Cr, Cu, Ni, Pb, Sr, V and Zn) showed statistically significant decrease from the first to the third heights of bags exposure. In the tunnel experiment, from inner to out of the tunnel, for Al, Ba, Cd, Co, Cr, Cu, Fe, K and Zn, decreasing trend of concentrations was obtained. Significantly higher concentration of the elements was pronounced for the tunnel in comparison with the street canyons. The results indicate that the use of S. girgensohnii moss bags is a simple, sensitive and inexpensive way to monitor the small-scale inner city spatial distribution of airborne major and trace element content. PMID:23430735

  5. The synchronous active neutron detection assay system

    International Nuclear Information System (INIS)

    We have begun to develop a novel technique for active neutron assay of fissile material in spent nuclear fuel. This approach will exploit a 14-MeV neutron generator developed by Schlumberger. The technique, termed synchronous active neutron detection (SAND), follows a method used routinely in other branches of physics to detect very small signals in presence of large backgrounds. Synchronous detection instruments are widely available commercially and are termed ''lock-in'' amplifiers. We have implemented a digital lock-in amplifier in conjunction with the Schlumberger neutron generator to explore the possibility of synchronous detection with active neutrons. The Schlumberger system can operate at up to a 50% duty factor, in effect, a square wave of neutron yield. Results are preliminary but promising. The system is capable of resolving the fissile material contained in a small fraction of the fuel rods in a cold fuel assembly; it also appears resilient to background neutron interference. The interrogating neutrons appear to be non-thermal and penetrating. Work remains to fully explore relevant physics and optimize instrument design

  6. Active biomonitoring of trace heavy metals using fish ( Oreochromis niloticus) as bioindicator species. The case of Nakivubo wetland along Lake Victoria

    Science.gov (United States)

    Birungi, Z.; Masola, B.; Zaranyika, M. F.; Naigaga, I.; Marshall, B.

    The Nakivubo wetland in Uganda, which feeds Lake Victoria at Murchison bay, has become severely degraded over recent years and is particularly threatened by the expansion of industry, settlement and cultivation on its fertile fringes. The aim of this study was to actively biomonitor selected trace heavy metals using Nile tilapia ( Oreochromis niloticus). Nile tilapia was set in cages at six sampling sites in Murchison bay for a period of six weeks, and sampling was done every 2 weeks for active biomonitoring and weekly for physico-chemical variables. The control (site 7) was at the Aquaculture Research and Development centre, Uganda. Fish tissue was dissected and gills, liver and muscle removed for heavy metal analysis. Water samples and fish tissue from each site were analysed using Atomic Absorption Spectrophotometer (AAS) to determine metal concentrations of zinc, copper, chromium and manganese. Site 4 had the highest average NH 4-N of 14.28 ± 12.73 mg/l which was above effluent standards for Uganda. From the findings, there were significantly higher concentrations of heavy metals in fish than in water ( p > 0.01). Fish kills were recorded highest for sites 4 (55%), 5 (77.5%) and 6 (60%) in less than six weeks indicating high levels of pollution. Gills showed the highest accumulation of copper after a period of six weeks as compared to other metals with a mean ± SE of 11.7 μg/mg wet weight. In general, the order of accumulation of metals in tissue after six weeks was in order; copper > zinc > chromium > manganese and gills > liver > muscle. In conclusion, active biomonitoring was found to be a good tool for monitoring water quality as it integrates responses to combinations of all contaminants thereby indicating overall effects in a water body. To improve the study, there is need to incorporate post mortem studies and biomarker analysis since the later can give early warning of pollution before fish kills are observed.

  7. Biomonitoring of air pollution through trace element analysis

    International Nuclear Information System (INIS)

    Studies are being carried out to determine the potential and reliability in the use of local lichen species for biomonitoring air pollution in Ghana. The location of most of the gold mines in forest areas of the country presents the gold mining industry as a suitable setting for such investigations. The nuclear-related techniques being used in the multielement analysis of lichen samples and air filter samples are instrumental neutron activation analysis (Miniature Neutron Source Reactor) and energy dispersive x-ray fluorescence analysis (tube-excitation). Validation of the quantitative methods of the INAA through analysis of standard certified reference materials of orchard leaves NBS SRM 1571 and BCR-CRM No. 279 gave very good results for most elements analyzed. Elemental analysis of identified lichen samples will be done bearing in mind microclimatic factors, specie type and nature of soil. (author)

  8. Biomonitoring of air pollution through trace element analysis

    International Nuclear Information System (INIS)

    Studies are being carried out to determine the potential and reliability in the use of local lichen species for biomonitoring air pollution in Ghana. The location of most of the gold mines in forest areas of the country presents the gold mining industry as a suitable setting for such investigations. The nuclear-related techniques being used in the multielement analysis of lichen samples and air filter samples are instrumental neutron activation analysis (Miniature Neutron Source Reactor) and energy dispersive x-ray fluorescence analysis (tube-excitation). Validation of the quantitative methods of the INAA through analysis of standard and certified reference materials of orchard leaves NBS SRM 1571 and BCR-CRM No. 279 gave very good results for most elements analyzed. Elemental analysis of identified lichen samples will be done beating in mind microclimatic factors, specie type and nature of soil. (author)

  9. Neutron activation analysis of reference materials

    International Nuclear Information System (INIS)

    The importance is pointed out of neutron activation analysis in the preparation of reference materials, and studies are reported conducted recently by UJV. Instrumental neutron activation analysis has been used in testing homogeneity and in determining 28 elements in newly prepared reference standards of coal fly ash designated ENO, EOP and ECH. For accuracy testing, the same method was used in the analysis of NBS SRM-1633a Trace Elements in Coal Fly Ash and IAEA CRM Soil-5 and RM Soil-7. Radiochemical neutron activation analysis was used in determining Cd, Cu, Mn, Mo, and Zn in biological materials NBS SRM-1577 Bovine Liver, Bowen's Kale and in IAEA RM Milk Powder A-11 and Animal Muscle H-4. In all instances very good precision and accuracy of neutron activation analysis results were shown. (author)

  10. Instrumental neutron activation analysis - a routine method

    International Nuclear Information System (INIS)

    This thesis describes the way in which at IRI instrumental neutron activation analysis (INAA) has been developed into an automated system for routine analysis. The basis of this work are 20 publications describing the development of INAA since 1968. (Auth.)

  11. Neutron activation analysis of Tradescantia Pallida plant for environmental pollutant monitoring

    International Nuclear Information System (INIS)

    Tradescantia pallida (Rose) D.R. Hunt. cv. Purpurea is a plant from Commelinaceae family easily cultivated even in regions with high level of pollution. In recent years, Tradescantia plants have become widely acknowledged for detection of clastogenic effects of heavy metal ions by micronuclei assay and it is suggested to be used to biomonitor metal-contaminated soils. In this work, elemental concentrations were determined in T. pallida plant leaves collected in two sites of Sao Paulo city: Jabaquara and Cidade Universitaria and from a clean region called Caucaia do Norte, to evaluate the possibility of using this species in the atmospheric pollutant biomonitoring. The method of instrumental neutron activation analysis was used in the evaluation of elements accumulated by this plant. Comparisons were made between the results obtained for T. pallida from different sites. The accuracy and the precision of the analytical results were also evaluated by analyzing certified reference materials NIST 1515 Apple Leaves and NIST 1570a Spinach Leaves. (author)

  12. Ethical issues related to biomonitoring studies on children

    DEFF Research Database (Denmark)

    Pedersen, Marie; Merlo, Domenico Franco; Knudsen, Lisbeth E.

    2007-01-01

    data respecting data protection including the right to know or not to know. Data protection is important because stakeholders may also ask for insight at various steps during human biomonitoring activities including children. Finally it is generally recommended that aim, methods, and results from...... biomonitoring studies should be communicated and study persons notified for further use of data and samples....

  13. Air pollution assessment in two Moroccan cities using instrumental neutron activation analysis on bio-accumulators

    International Nuclear Information System (INIS)

    Full text: Biomonitoring is an appropriate tool for the air pollution assessment studies. In this work, lichens and barks have been used as bio-accumulators in several sites in two Moroccan cities (Rabat and Mohammadia). The specific ability of absorbing and accumulating heavy metals and toxic element from the air, their longevity and resistance to the environmental stresses, make those bioindicators suitable for this kind of studies. The Instrumental Neutron Activation Analysis (INAA) is universally accepted as one of the most reliable analytical tools for trace and ultra-trace elements determination. Its use in trace elements atmospheric pollution related studies has been and is still extensive as can be demonstrated by several specific works and detailed reviews. In this work, a preliminary investigation employing lichens, barks and instrumental neutron activation analysis (INAA) was carried out to evaluate the trace elements distribution in six different areas of Rabat and Mohammadia cities characterised by the presence of many industries and heavy traffic. Samples were irradiated with thermal neutrons in a nuclear reactor and the induced activity was counted using high-resolution Germanium-Lithium detectors. More than 30 elements were determined using two modes : short irradiation (1 minute) and long irradiation (17 hours). Accuracy and quality control were assessed using the reference standard material IAEA-336. This was less than 1% for major and about 5 to 10% for traces.

  14. KFUPM fast neutron activation analysis facility

    International Nuclear Information System (INIS)

    A newly established Fast Neutron Activation Analysis facility at the Energy Research Laboratory is described. The facility mainly consists of a fast neutron irradiation station and a gamma ray counting station. Both stations are connected by a fast pneumatic sample transfer system which transports the sample from the irradiation station to the counting station in a short time of 3 s. The fast neutron activation analysis facility has been tested by measuring the 27A(n, α)24Na and 115In(n, n')115mIn cross sections at 14.8 and 2.5 MeV neutron energies, respectively. Within the experimental uncertainties, the measured cross sections for these elements agree with the published values. (orig.)

  15. Neutron activation analysis of Tradescantia Pallida plant for environmental pollutant monitoring; Analise por ativacao com neutrons da planta Tradescantia Pallida para uso na monitoracao de poluentes atmosfericos

    Energy Technology Data Exchange (ETDEWEB)

    Tavaraya, Andre K.; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil); Sumita, Nairo M.; Saldiva, Paulo H.N. [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina

    2002-07-01

    Tradescantia pallida (Rose) D.R. Hunt. cv. Purpurea is a plant from Commelinaceae family easily cultivated even in regions with high level of pollution. In recent years, Tradescantia plants have become widely acknowledged for detection of clastogenic effects of heavy metal ions by micronuclei assay and it is suggested to be used to biomonitor metal-contaminated soils. In this work, elemental concentrations were determined in T. pallida plant leaves collected in two sites of Sao Paulo city: Jabaquara and Cidade Universitaria and from a clean region called Caucaia do Norte, to evaluate the possibility of using this species in the atmospheric pollutant biomonitoring. The method of instrumental neutron activation analysis was used in the evaluation of elements accumulated by this plant. Comparisons were made between the results obtained for T. pallida from different sites. The accuracy and the precision of the analytical results were also evaluated by analyzing certified reference materials NIST 1515 Apple Leaves and NIST 1570a Spinach Leaves. (author)

  16. Applications of neutron activation analysis in industry

    International Nuclear Information System (INIS)

    Neutron activation analysis technique is discussed in brief. This technique is used for quality control of raw materials, process materials and finished products, as well as activities in research and development for the improvement of the products and new products. The uses of this technique in several experienced industries are mentioned (author)

  17. Carbon Activation Diagnostic for Tertiary Neutron Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Glebov, V.Yu.; Stoeckl, C.; Sangster, T.C.; Meyerhofer, D.D.; Radha, P.B.; Padalino, S.; Baumgart, L.; Fuschino, J.

    2003-03-28

    OAK B202 The yield of tertiary neutrons with energies greater than 20 MeV has been proposed to determine the high rho R of inertial confinement fusion targets. The activation of carbon is a valuable measurement technique because of its high reaction threshold, the availability of high-purity samples, and relatively low cost. The 12C(n,2n)11C reaction has a Q value of 18.7 MeV, well above the 14.1 MeV primary DT neutron energy. The isotope 11C decays with a half-life of 20.3 min and emits a positron, resulting in the production of two back-to-back, 511 keV gamma rays upon annihilation. The positron decay of 11C is nearly identical to the copper decay used in the activation measurements of 14.1 MeV primary DT yields; therefore, the present copper activation gamma-detection system can be used to detect the tertiary-produced carbon activation. Because the tertiary neutron yield is more than six orders of magnitude lower than primary neutron yield, the carbon activation diagnostic requires ultrapure carbon samples, free from any positron-emitting contamination. In recent years we have developed carbon purification, packaging, and handling procedures that minimize the contamination signal to a level low enough to use carbon activation for tertiary neutron measurements in direct-drive implosion experiments with DT cryogenic targets on OMEGA. Experimental results of contamination measurements in carbon samples performed on high-neutron-yield shots on OMEGA in 2001-2002 will be presented. A concept for implementing a carbon activation system on the National Ignition Facility (NIF)will be discussed.

  18. Neutron Activation analysis of waste water

    International Nuclear Information System (INIS)

    An instrumental neutron activation analysis for the simultaneous determination of chlorine, bromine, sodium, manganese, cobalt, copper, chromium, zinc, nickel, antimony and iron in waste water is described. They were determined in waste water samples under normal conditions by non-destructive neutron activation simultaneously using a suitable monostandard method. Standardized water samples were used and irradiated in polyethylene ampoules at a neutron flux of 1013 cm-2 s-1 for periods of 1 minute, 1 and 10 hours. A Ge hyperpure detector was used for your activity determination, with count times of 60, 180, 300 and 600 seconds. The obtained results show than the method can be utilized for the determination of this elements without realize anything previous treatment of the samples. (Author)

  19. A review of conventional explosives detection using active neutron interrogation

    International Nuclear Information System (INIS)

    Conventional explosives are relatively easy to obtain and may cause massive harm to people and property. There are several tools employed by law enforcement to detect explosives, but these can be subverted. Active neutron interrogation is a viable alternative to those techniques, and includes: fast neutron analysis, thermal neutron analysis, pulsed fast/thermal neutron analysis, neutron elastic scatter, and fast neutron radiography. These methods vary based on neutron energy and radiation detected. A thorough review of the principles behind, advantages, and disadvantages of the different types of active neutron interrogation is presented. (author)

  20. Neutron beam characteristics of the prompt gamma neutron activation analysis system at HANARO

    International Nuclear Information System (INIS)

    Neutron beam characteristics of the Prompt Gamma Neutron Activation Analysis facility at HANARO were measured. The neutron beam of this facility is polychromatic thermal neutrons diffracted vertically by a set of pyrolytic graphite crystals at the Bragg angle of 45 .deg. from a horizontal beam line. Three conditions of thermal neutron extraction were applied by varying graphite crystal thickness and focusing geometry of diffracted beam. Thermal neutron profile, thermal neutron flux and Cd-ratio were measured at the sample position for each extraction condition. Thermal neutron flux of 6.1x107 n/cm2s and Cd-ratio of 364 are achieved finally

  1. Epiphytic lichens as quantitative biomonitors for atmospheric element deposition

    International Nuclear Information System (INIS)

    Epiphytic lichens are being used as passive and active biomonitors of trace elements in Slovenia. The lichen Hypogymnia physodes (L.) Nyl. was exposed at three locations (two in the vicinity of a coal fired-power plant, and one at a reference location) for 8 months. At the same locations air particulate matter and total deposition were collected on a monthly basis. The k0-method of neutron activation analysis, using the TRIGA Mark II reactor at the 'Jozef Stefan' Institute, was employed for multielemental nondestructive analysis of all samples. The influence of the power plant on the concentration levels of some elements in the transplanted lichens, air particulates and total deposition is discussed and their correlation presented. (author)

  2. Study of air pollution in Chile using biomonitors

    International Nuclear Information System (INIS)

    A project has been undertaken within the framework of a Co-ordinated Research Programme (CRP) supported by the International Atomic Energy Agency (IAEA) to carry out a long term study on atmospheric air pollution in Chile using biomonitors. The present paper describes the activities undertaken within the framework of this project. Sampling of different lichens species has been performed in clean areas (native forest), preparation of such samples has been done under controlled, cryogenic conditions and analysed by neutron activation analysis. Participation in an intercomparison run organized by the IAEA for the determination of trace and minor elements in two lichens samples, has also been carried out. Transplant of lichens collected in clean areas has been done in Santiago. (author)

  3. Interferences in reactor neutron activation analyses

    International Nuclear Information System (INIS)

    It has been shown that interfering reactions may occur in neutron activation analyses of aluminum and zinc matrixes, commonly used in nuclear areas. The interferences analysed were: Al2713 (n, α) Na2411 and Zn6430 (n, p) Cu6429. The method used was the non-destructive neutron activation analysis and the spectra were obtained in a 1024 multichannel system coupled with a Ge(Li) detector. Sodium was detected in aluminum samples from the reactor tank and pneumatic transfer system. The independence of the sodium concentration in samples in the range of 0 - 100 ppm is shown by the attenuation obtained with the samples encapsulated in cadmium. (Author)

  4. Design of Neutron Activation Analysis Laboratorium Room

    International Nuclear Information System (INIS)

    Base on the planning to increase of the research and service quality in the ''Neutron activation analysis'' (APN),the design of mentioned ''Neutron activation analysis laboratories room'' has been done in the multi purpose reactor G.A. Siwabessy. By the using the designed installation, the irradiation preparation and counting sample can be done. The design doing by determination of installation lay out and maximum particle contain in the air. The design installation required a unit of 1 HP blower, a unit of 1 HP split air condition and 2 units 1200 x 800 mm HEPA filter. This paper concluded that this design is feasible to fabricated

  5. Neutron activation analysis of geochemical samples

    International Nuclear Information System (INIS)

    The present paper will describe the work done at the Technical Research Centre of Finland in developing methods for the large-scale activation analysis of samples for the geochemical prospecting of metals. The geochemical prospecting for uranium started in Finland in 1974 and consequently a manually operated device for the delayed neutron activation analysis of uranium was taken into use. During 1974 9000 samples were analyzed. The small capacity of the analyzer made it necessary to develop a completely automated analyzer which was taken into use in August 1975. Since then 20000-30000 samples have been analyzed annually the annual capacity being about 60000 samples when running seven hours per day. Multielemental instrumental neutron activation analysis is used for the analysis of more than 40 elements. Using instrumental epithermal neutron activation analysis 25-27 elements can be analyzed using one irradiation and 20 min measurement. During 1982 12000 samples were analyzed for mining companies and Geological Survey of Finland. The capacity is 600 samples per week. Besides these two analytical methods the analysis of lanthanoids is an important part of the work. 11 lanthanoids have been analyzed using instrumental neutron activation analysis. Radiochemical separation methods have been developed for several elements to improve the sensitivity of the analysis

  6. New studies in forensic neutron activation analysis

    International Nuclear Information System (INIS)

    Three recently completed studies in forensic neutron activation analysis are reported: a study of 0.22-caliber rimfire cartridge primers, a large-scale study of shotgun pellets, and a new 5-element procedure for the analysis of bullet-lead and shotgun-pellet samples. (author) 12 refs

  7. New studies in forensic neutron activation analysis

    International Nuclear Information System (INIS)

    Earlier studies in forensic neutron activation analysis are being extended in This Laboratory. Three of these new studies are reported here: 1) a study of 0.22-caliber rimfire cartridge primers, 2) a large-scale study of shotgun pellets, and 3) a new 5-element procedure for the analysis of bullet-lead and shotgun-pellet samples. (author)

  8. Neutron Activation Analysis with k0 Standardization

    International Nuclear Information System (INIS)

    SCK-CEN's programme on Neutron Activation Analysis with k0-standardisation aims to: (1) develop and implement k0-standardisation method for NAA; (2) to exploit the inherent qualities of NAA such as accuracy, traceability, and multi-element capability; (3) to acquire technical spin-off for nuclear measurements services. Main achievements in 1997 are reported

  9. Neutron activation analysis helps in picture attribution

    International Nuclear Information System (INIS)

    The neutron activation analysis application for obtaining the data useful for proper attribution of paintings has been presented on the base of several examples. The identification on this way of dye elements, pigments and other painting materials is an important element among the physico-chemical methods helping the attribution procedure of old painting objects

  10. Passive neutron dosemeter with activation detector

    Energy Technology Data Exchange (ETDEWEB)

    Valero L, C.; Banuelos F, A.; Guzman G, K. A.; Borja H, C. G.; Hernandez D, V. M.; Vega C, H. R., E-mail: fermineutron@yahoo.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2011-10-15

    A passive neutron dosemeter with {sup 197}Au activation detector has been developed. The area dosemeter was made as a 20.5 {phi} x 20.5 cm{sup 2} polyethylene moderator, with a polyethylene pug where a {sup 197}Au foil can be located either parallel or perpendicular to moderator axis. Using Monte Carlo methods, with the MCNP5 code. With the fluence response and the fluence-to-equivalent dose conversion coefficients from ICRP-74, responses to H*(10) were also calculated, these were compared against responses of commercially available neutron area monitors and dosemeters. (Author)

  11. Fast neutron activation measurement of concealed explosives

    International Nuclear Information System (INIS)

    Spectra of 0.511 MeV γ-ray of nitrogen and 6.13 MeV γ-ray of oxygen and their ratio are measured by using two neutron sourses of different yield for explosive or non-explosive materials. Sensitivity and detecting speed are determined. A planar distribution of the explosive or non-explosive materials with different contents of nitrogen and oxygen is given. The whole design and security of detection method of fast neutron activation analysis system is discussed for concealed explosives

  12. High-capacity neutron activation analysis facility

    International Nuclear Information System (INIS)

    A high-capacity neutron activation analysis facility, the Reactor Activation Facility, was designed and built and has been in operation for about a year at one of the Savannah River Plant's production reactors. The facility determines uranium and about 19 other elements in hydrogeochemical samples collected in the National Uranium Resource Evaluation program, which is sponsored and funded by the United States Department of Energy, Grand Junction Office. The facility has a demonstrated average analysis rate of over 10,000 samples per month, and a peak rate of over 16,000 samples per month. Uranium is determined by cyclic activation and delayed neutron counting of the U-235 fission products; other elements are determined from gamma-ray spectra recorded in subsequent irradiation, decay, and counting steps. The method relies on the absolute activation technique and is highly automated for round-the-clock unattended operation

  13. BIOMONITORING USING AQUATIC VEGETATION

    Science.gov (United States)

    This chapter provides an overview of the state-of-the-science as related to the phytoassessment techniques used in environmental biomonitoring and the hazard assessment process for chemicals. The emphasis is on freshwater angiosperms and bryophytes. Algal species, which are prese...

  14. Application of cold neutron prompt-gamma activation analysis in environmental studies of aquatic plants

    International Nuclear Information System (INIS)

    This paper describes the use of cold-neutron prompt-gamma activation analysis (CNPGAA) to determine carbon, nitrogen, and phosphorus in the aquatic plant Typha domingensis, commonly known as cattail, during spring and fall seasons. According to studies of the Florida Everglades, cattail replaces sawgrass as a result of nutrient enrichment from farm water runoff. Nutrient enrichment, especially phosphorus, in sediment and the water column can lead to undesirable expansion. Early signs of this expansion are apparent in the Apalachicola River floodplain near Apalachicola, Florida, USA. This research project is designed to use cattails as biomonitors of nutrient enrichment in the lower Apalachicola River floodplain. Determination of carbon, nitrogen, and phosphorus in cattail using cold neutron prompt-gamma activation has been developed in our previous studies at the CNPGAA facility at the National Institute of Standards and Technology (NIST), USA. The results of numerous field samples, collected from the study area during spring and fall seasons in 2002, will be presented in this paper. (author)

  15. Air Pollution with Heavy Metals and Radionuclides in Slovakia Studied by the Moss Biomonitoring Technique

    CERN Document Server

    Florek, M; Mankovska, B; Oprea, K; Pavlov, S S; Steinnes, E; Sykora, I

    2001-01-01

    Applying the moss biomonitoring technique to air pollution studies in Slovakia, heavy metals, rare-earth elements, actinides (U and Th) were determined in 86 moss samples from the European moss survey 2000 by means of epithermal neutron activation analysis at the IBR-2 reactor (Dubna). Such elements as In, Cu, Cd, Hg and Pb were determined by AAS in the Forest Research Institute, Zvolen (Slovakia). The results of measurement of the natural radionuclides ^{210}Pb, ^{7}Be, ^{137}Cs and ^{40}K in 11 samples of moss are also reported. A comparison with the results from moss surveys 1991 and 1995 revealed previously unknown tendencies of air pollution in the examined areas.

  16. Analysis of tree bark samples for air pollution biomonitoring of an urban area

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Ana Paula G.; Negri, Elnara M.; Saldiva, Paulo H.N., E-mail: paulista@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina. Dept. de Patologia; Saiki, Mitiko; Scapin, Marcos A.; Ribeiro, Andreza P.; Salvador, Vera L., E-mail: mitiko@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    Air pollution is receiving much attention as a public health problem around the world due to its adverse health effects from exposures by urban populations. Within this context, the use of vegetal biomonitoring to evaluate air quality has been investigated throughout the world. Air pollutant levels are high in the city of Sao Paulo, SP, Brazil and being the vehicle emissions its main source. The aim of this study was to evaluate concentrations of As, Ba, Br, Ca, Co, Cr, Cu, Fe, Mn, Pb, S, Sb and Zn in tree bark samples used as biomonitor of urban air pollution. Concentrations of these elements were determined in barks collected in trees of the Ibirapuera Park, one of the biggest and most visited parks of the city of Sao Paulo city. Samples of tree barks were also collected in a site outside the city of Sao Paulo, in a rural area of Embu-Guacu, considered as a control site. The element concentrations were determined by the methods of Instrumental Neutron Activation Analysis (INAA) and of Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF). The findings of this study showed that tree bark samples may be used as biomonitors of urban air pollution in a micro scale, and both techniques, INAA and EDXRF, can be used to evaluate element concentrations in tree bark samples. (author)

  17. Analysis of tree bark samples for air pollution biomonitoring of an urban area

    International Nuclear Information System (INIS)

    Air pollution is receiving much attention as a public health problem around the world due to its adverse health effects from exposures by urban populations. Within this context, the use of vegetal biomonitoring to evaluate air quality has been investigated throughout the world. Air pollutant levels are high in the city of Sao Paulo, SP, Brazil and being the vehicle emissions its main source. The aim of this study was to evaluate concentrations of As, Ba, Br, Ca, Co, Cr, Cu, Fe, Mn, Pb, S, Sb and Zn in tree bark samples used as biomonitor of urban air pollution. Concentrations of these elements were determined in barks collected in trees of the Ibirapuera Park, one of the biggest and most visited parks of the city of Sao Paulo city. Samples of tree barks were also collected in a site outside the city of Sao Paulo, in a rural area of Embu-Guacu, considered as a control site. The element concentrations were determined by the methods of Instrumental Neutron Activation Analysis (INAA) and of Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF). The findings of this study showed that tree bark samples may be used as biomonitors of urban air pollution in a micro scale, and both techniques, INAA and EDXRF, can be used to evaluate element concentrations in tree bark samples. (author)

  18. Fast-Neutron Surveys Using Indium-Foil Activation

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, Lloyd D.; Smith, Alan R.

    1958-08-13

    Activation of indium foils by thermal neutrons has been applied to measurement of fast-neutron fluxes. Foils are encased in paraffin spheres placed in cadmium boxes. The high-energy neutrons that penetrate the cadmium become thermal neutrons; the thermal-neutron flux is proportional to the incident fast-neutron flux over a range of about 20 kev to 20 Mev. The foils are removed from the boxes and counted on a methane-flow proportional counter. High instantaneous neutron fluxes are easily detected and counted by use of these foils. Many simultaneous measurements have been made easily by this method.

  19. Applications of neutron activation analysis technique

    International Nuclear Information System (INIS)

    The technique was developed as far back as 1936 by G. Hevesy and H. Levy for the analysis of Dy using an isotopic source. Approximately 40 elements can be analyzed by instrumental neutron activation analysis (INNA) technique with neutrons from a nuclear reactor. By applying radiochemical separation, the number of elements that can be analysed may be increased to almost 70. Compared with other analytical methods used in environmental and industrial research, NAA has some unique features. These are multi-element capability, rapidity, reproducibility of results, complementarity to other methods, freedom from analytical blank and independency of chemical state of elements. There are several types of neutron sources namely: nuclear reactors, accelerator-based and radioisotope-based sources, but nuclear reactors with high fluxes of neutrons from the fission of 235U give the most intense irradiation, and hence the highest available sensitivities for NAA. In this paper, the applications of NAA of socio-economic importance are discussed. The benefits of using NAA and related nuclear techniques for on-line applications in industrial process control are highlighted. A brief description of the NAA set-ups at CERT is enumerated. Finally, NAA is compared with other leading analytical techniques

  20. Neutron spectra unfolding from measured detector activations

    International Nuclear Information System (INIS)

    Our knowledge of the neutron spectrum in irradiation facilities essentially rests on the calculation and on the unfolding resp. adjustment based on measured activations, more generally said reactions rates, since the other direct or indirect experimental methods here frequently are not applicable on account of technical reasons. In this situation the neutronic calculation by no means renders superfluous the unfolding because the measurements can confirm or possibly correct resp. improve the calculational results. The FORTRAN code SAND-MX2 is a contribution of the KFA to the international repertoire of unfolding codes. With regard to its contents it is one of the newer versions of the original code SAND-II which are presently used as SAND-II also in the laboratories of several countries as especially practice related unfolding calculational methods. This report may serve as an instruction manual for the routinely neutron spectrum unfolding by means of the code SAND-MX2. It appeared to us not to be superfluous in addition to the above mentioned aim also to give a general view of the present situation in unfolding technique and to touch shortly the other advanced methods because we believed thereby also to give a better understanding of the characteristic features of our programme. In some laboratories several of the here described calculational programmes are alternatively in current use for the purpose of giving a greater confidence to the result of the neutron spectrum unfolding in question. (orig.)

  1. Neutron activation analysis of biological substances

    International Nuclear Information System (INIS)

    A Bowen cabbage sample was used as a reference material for the neutron activation studies, and the method was checked by the analysis of other biological substances (blood or serum etc.). For nondestructive measurements also some non-trace elements were determined in order to decide whether the activation analysis is a useful means for such measurements. The new activation analysis procedure was used for biomedical studies as, e.g., for trace element determination in body fluids, and for the analysis of inorganic components in air samples. (R.P.)

  2. Neutron activation analysis of geothermal water

    International Nuclear Information System (INIS)

    Instrumental technique of determination of 16 microimpurities in geothermal water samples is worked out. Probes and standard samples with cadmium filter have been irradiated by the thermal neutron flux of 5x1013 neutr.xcm-2xc-1. Cadmium filter permitted to considerably decrease 24Na radio activity caused by its high content in geothermal water, and to measure radioactivity in several hours after irradiation. Radioactivity measurement has been carried out without probe unpacking

  3. Reactor neutron activation analysis of industrial materials

    International Nuclear Information System (INIS)

    The specific application of neutron activation analysis (n.a.a.) for industrial materials is demonstrated by the determination of impurities in BeO, Al, Si, Cu, Ge, GaP, GaAs, steel, and irradiated uranium. A group scheme gives an orientation about the possibilities of n.a.a. The use of different standards, methods for the measurement of low radioactivities and errors caused by recoil reaction and radiation stimulated diffusion are discussed. (author)

  4. Development of Cold Neutron Activation Station at HANARO Cold Neutron Source

    International Nuclear Information System (INIS)

    A new cold neutron source at the HANARO Research Reactor had been constructed in the framework of a five-year project, and ended in 2009. It has seven neutron guides, among which five guides were already allocated for a number of neutron scattering instruments. A new two-year project to develop a Cold Neutron Activation Station (CONAS) was carried out at the two neutron guides since May 2010, which was supported by the program of the Ministry of Education, Science and Technology, Korea. Fig. 1 shows the location of CONAS. CONAS is a complex facility including several radioanalytical instruments utilizing neutron capture reaction to analyze elements in a sample. It was designed to include three instruments like a CN-PGAA (Cold Neutron - Prompt Gamma Activation Analysis), a CN-NIPS (Cold Neutron - Neutron Induced Pair Spectrometer), and a CN-NDP (Cold Neutron - Neutron-induced prompt charged particle Depth Profiling). Fig. 2 shows the conceptual configuration of the CONAS concrete bioshield and the instruments. CN-PGAA and CN-NIPS measure the gamma-rays promptly emitted from the sample after neutron capture, whereas CN-NDP is a probe to measure the charged particles emitted from the sample surface after neutron capture. For this, we constructed two cold neutron guides called CG1 and CG2B guides from the CNS

  5. Determination of uranium in human head hair of a Brazilian populational group by epithermal neutron activation analysis

    International Nuclear Information System (INIS)

    Hair analysis is extensively used in forensic sciences, assessment of occupational or environmental exposure and in some cases also for clinical and nutritional studies. Hair has a series of advantages in relation to other biomonitors, like blood and urine, since it is very easy to collect, very stable at room temperature and it represents not only instantaneous concentrations, but it can reveal the exposure along a given period of time. The assessment of environmental or occupational exposure to uranium is generally done by means of urine analysis, although a few papers have described attempts to use hair as a biomonitor. In the present work, epithermal neutron activation analysis has been used to establish base-line concentrations for a Brazilian populational group, living in Sao Paulo and not exposed to uranium, either environmentally or occupationally. For quality control, the reference materials Pine Needles NIST 1575 and Basalt USGS BCR-1 were used. The concentrations obtained for the control population studied up to now varied from about 2 to 50 ng x g-1. (author)

  6. Magnetic Electrochemical Sensing Platform for Biomonitoring of Exposure to Organophosphorus Pesticides and Nerve Agents Based on Simultaneous Measurement of Total Enzyme Amount and Enzyme Activity

    Energy Technology Data Exchange (ETDEWEB)

    Du, Dan; Wang, Jun; Wang, Limin; Lu, Donglai; Smith, Jordan N.; Timchalk, Charles; Lin, Yuehe

    2011-05-15

    We report a new approach for electrochemical quantification of enzymatic inhibition and phosphorylation for biomonitoring of exposure to organophosphorus (OP) pesticides and nerve agents based on a magnetic beads (MBs) immunosensing platform. The principle of this approach is based on the combination of MBs immuno-capture based enzyme activity assay and competitive immunoassay of total amount of enzyme for simultaneous detection of enzyme inhibition and phosphorylation in biological fluids. Butyrylcholinesterase (BChE) was chosen as a model enzyme. In competitive immunoassay, the target total BChE in a sample (mixture of OP-inhibited BChE and active BChE) competes with the BChE modified on the MBs to bind to the limited anti-BChE antibody labeled with quantum dots (QDs-anti-BChE), and followed by electrochemical stripping analysis of the bound QDs conjugate on the MBs. This assay shows a linear response over the total BChE concentration range of 0.1~20 nM. Simultaneously, real time BChE activity was measured on an electrochemical carbon nanotube-based sensor coupled with microflow injection system after immuno-capture by MBs-anti-BChE conjugate. Therefore, the formed phosphorylated adduct (OP-BChE) can be estimated by the difference values of the total amount BChE (including active and OP-inhibited) and active BChE from established calibration curves. This approach not only eliminates the difficulty in screening of low-dose OP exposure (less than 20% inhibition of BChE) because of individual variation of BChE values, but also avoids the drawback of the scarce availability of OP-BChE antibody. It is sensitive enough to detect 0.5 nM OP-BChE, which is less than 2% BChE inhibition. This method offers a new method for rapid, accurate, selective and inexpensive quantification of phosphorylated adducts and enzyme inhibition for biomonitoring of OP and nerve agent exposures.

  7. Active neutron/photon personal dosemeters

    International Nuclear Information System (INIS)

    Though active personal dosemeters for photon fields reflect already a high level of development, there is still a need to advance the design of dosemeters for use in mixed neutron/photon fields and especially for monitoring the staff of nuclear power plants and the personnel accompanying transports of spent fuel flasks. The measurement of the neutron component is usually associated with problems. After a short description of the complex mixed fields in the nuclear fuel cycle, the commercially available active dosemeters and those under development will be listed and problems arising from their use in these fields will be discussed. Two new developments, the Siemens EPD-N2 and the PTB DOS-2002, which both are capable of indicating neutron and photon doses, will be described and discussed in detail. New response functions with respect to personal dose equivalent Hp(10) will be presented for neutrons. They have been determined by measurements in the quasi-monoenergetic reference fields at PTB in the energy range from 24 keV to 14.8 MeV and in fields with broad spectral distributions using the radionuclide sources 252Cf(bare), 252Cf(D2O,mod) - with and without cadmium shielding - 241Am-Be as well as a thermal neutron beam. The spectral distributions of all fields and the readings of the dosemeters in these fields were taken as inputs for an unfolding procedure to determine the dosemeter response in the overall energy region from thermal to 15 MeV. The procedure was tested by folding the dosemeter response with the broad neutron spectra and comparing with the readings of the dosemeters. Another problem in practical workplace fields is linked with high energy photons. Photons with energies from 6 MeV to 7 MeV from the 16O(n,pγ) reaction contribute to dose, particularly at reactors, and have to be taken into account when dosemeters are processed. Measurements with high energy photons were therefore performed with both devices and will be discussed. Finally, practical

  8. Neutron activation analysis of geological materials

    International Nuclear Information System (INIS)

    Neutron activation analysis (NAA) is an extremely sensitive, selective and precise method, which yields a wealth of elemental information from even a small-sized sample. With the recent advances in nuclear reactors and high-efficiency and high-resolution semiconductor detectors, NAA has become a powerful method for multielemental analysis. The concentration of major, minor, and trace elements vary from 1 to 4 orders of magnitude in geological materials. By varying neutron fluxes, irradiation times, decay and counting intervals and using both instrumental and radiochemical techniques in NAA, it is possible to accurately determine about 50 elements in a sample aliquant. The practical aspects of the NAA method as applied to geological materials are discussed in detail, and are demonstrated by the analysis of the United States Geological Survey (USGS) and the International Atomic Energy Agency (IAEA) standard reference geological materials. General aspects of the elemental interpretations in terrestrial samples are also discussed. (author)

  9. Prospects for absolute neutron activation analysis

    International Nuclear Information System (INIS)

    The desirability for absolute neutron activation analysis(ANAA) is two-fold. Results by the comparitor method are only as good as the standards used, and also the method offers a chance of having the final results available within minutes of completing the analysis. In the past ANAA was not seriously considered because of the scarcity and poor qaulity of the nuclear data that were available. This situation is however steadily improving and the possible applications are being investigated. This report reviews the present status by considering the basic activation equation, calculation of parameters, the factors of importance and the size error one might expect

  10. Neutron activation analysis applied to archaeological problems

    International Nuclear Information System (INIS)

    Among the various techniques, the main analytical methods used to characterize ceramics are undoubtedly XRF and INAA. The principles of NAA differ from those of XRF in that samples are irradiated by thermal neutrons from a nuclear reactor. During irradiation, a few neutrons are captured by the nuclei of atoms in the specimen. This process, called activation, causes some of the nuclei to become unstable. During and after neutron irradiation, these unstable nuclei emit γ rays with unique energies at rates defined by the characteristic half-lives of the radioactive nuclei. Identification of the radioactive nucleus is possible by measuring the γ ray energies. Determination of their intensities permits quantitative analysis of the elements in the sample. The use of NAA in ceramics by a combination of two or three irradiation, decay and measurement strategies allows the determination of the elements Ba, Ce, Cl, Co, Cs, Dy, Eu, Fe, Hf, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, U, Yb, Zn and Zr, if necessary by changing the irradiation, decay and measurement schemes. In general, XRF is more available, more rapid and less expensive than NAA. However, NAA offers a far greater number of elements, more sensitivity, superior precision and greater accuracy than XRF. On the other hand, NAA can be performed on extremely small samples (5-10 mg), meaning that only minor damage to valuable artefacts may be required

  11. The orientation effect in the activities of neutronic probes

    International Nuclear Information System (INIS)

    The formulae relating activity and position of a neutron irradiated Indium foil, have been verified experimentally. Measurements with both thin and thick foils for epithermal neutrons and with thick foils for thermal neutrons have been carried out. The experimental results agree qualitatively with the theoretical predictions. (Author)

  12. Neutron activation analysis of zirconium niobium alloys

    International Nuclear Information System (INIS)

    Full text: One of the important problems in nuclear reactor projecting is the choice of constructional materials, which meet to the requirements concerned with function, technical characteristics and expected performance of the reactor construction. Also it is necessary to take into account change of their properties under the influence of intensive neutron radiation. Zirconium and zirconium-niobium alloys are used in nuclear engineering as a fuel cladding and both matrix and impurity composition have an influence on their performance capabilities.Under intensive neutron radiation high content of undesirable trace elements in constructional materials can cause forming long-lived radionuclides with high induced activity and hence severe problems may occur at service, control of the equipment and carrying out experiments. Therefore analytical control of component and impurity composition of these materials is an important problem.Neutron activation analysis (NAA) is one of multielemental and high sensitivity methods, which widely applied for the analysis of high purity materials. Prior experiments have shown that instrumental NAA is not suitable for analysis of Zr-Nb alloys due to strong induced matrix activity. Therefore we have developed radiochemical procedure for separation of impurities from matrix elements. Study of the literature data has shown that zirconium and niobium are good extracted from hydrochloric medium by 0 75 M solution of di-2-ethylhexylphosphoric acid (DEHPA) in ortho-xylene. Also this system good extracts hafnium which being accompanying element has high content and interferes with determining impurity elements. To improve separation efficiency we have used 'DEHPA - ZM HCl' chromatography system. On the basis of the carried out researches the radiochemical NAA technique for analysis of high purity zirconium and zirconium-niobium alloys has been developed. The technique is based on extraction-chromatographic separation of matrix radionuclides

  13. Toxicological applications of neutron-activation analysis

    International Nuclear Information System (INIS)

    Thermal neutron-activation analysis is recognised as a useful tool for trace element studies in toxicology. This paper describes some recent applications of the technique to three elements when ingested by people in excess of normal intake Two of the elements (copper and chromium) are essential to life and one (bromine) is as yet unclassified. Three deaths were investiagted and trace element levels compared with normal levels from healthy subjects in the same geographical area who had died as a result of violence. (author)

  14. Quality assurance in biomedical neutron activation analysis

    International Nuclear Information System (INIS)

    The summary report represents an attempt to identify some of the possible sources of error in in vitro neutron activation analysis of trace elements applied to specimens of biomedical origin and to advise on practical means to avoid them. The report is intended as guidance for all involved in analysis, including sample collection and preparation for analysis. All these recommendations constitute part of quality assurance which is here taken to encompass the two concepts - quality control and quality assessment. Quality control is the mechanism established to control errors, while quality assessment is the mechanism used to verify that the analytical procedure is operating within acceptable limits

  15. Neutron activation analysis of medicinal plant extracts

    International Nuclear Information System (INIS)

    Instrumental neutron activation analysis was applied to the determination of the elements Br, Ca, Cl, Cs, Fe, K, La, Mg, Mn, Na, Rb and Zn in medicinal extracts obtained from Centella asiatica, Citrus aurantium L., Achyrolcline satureoides DC, Casearia sylvestris, Solano lycocarpum, Zingiber officinale Roscoe, Solidago microglossa and Stryphnondedron barbatiman plants. The elements Hg and Se were determined using radiochemical separation by means of retention of Se in HMD inorganic exchanger and solvent extraction of Hg by bismuth diethyldithiocarbamate solution. Precision and accuracy of the results were evaluated by analyzing biological reference materials. The therapeutic action of some elements found in plant extracts analyzed is briefly discussed. (author). 15 refs., 5 tabs

  16. Rapid radiochemical separations in neutron activation analysis

    International Nuclear Information System (INIS)

    Rapid radiochemical separation procedures based on the removal of metal ions by columns of C18-bonded silica gel after selective complexation are examined and the simplicity of the method demonstrated by its application to the determination of Mn, Cu and Zn in neutron-activated biological material. The method is rapid and reliable and readily adaptable in all radiochemical laboratories. An alternative separation procedure for selenium in blood plasma involving desalination and concentration of the selenium protein complex by gel filtration or ultrafiltration is briefly discussed. (author)

  17. Support system for Neutron Activation Analysis

    International Nuclear Information System (INIS)

    In the research reactor of JAERI, the Neutron Activation Analysis (NAA) has been utilized as a major part of an irradiation usage. To utilize NAA, research participants are always required to learn necessary technique. Therefore, we started to examine a support system that will enable to carry out INAA easily even by beginners. The system is composed of irradiation device, gamma-ray spectrometer and data analyzing instruments. The element concentration is calculated by using KAYZERO/SOLCOI software with the K0 standardization method. In this paper, we review on a construction of this INAA support system in JRR-3M of JAERI. (author)

  18. Neutron activation analysis of Etruscan pottery

    International Nuclear Information System (INIS)

    Neutron activation analysis (NAA) has been widely used in archaeology for compositional analysis of pottery samples taken from sites of archaeological importance. Elemental profiles can determine the place of manufacture. At Cornell, samples from an Etruscan site near Siena, Italy, are being studied. The goal of this study is to compile a trace element concentration profile for a large number of samples. These profiles will be matched with an existing data bank in an attempt to understand the place of origin for these samples. The 500 kW TRIGA reactor at the Ward Laboratory is used to collect NAA data for these samples. Experiments were done to set a procedure for the neutron activation analysis with respect to sample preparation, selection of irradiation container, definition of activation and counting parameters and data reduction. Currently, we are able to analyze some 27 elements in samples of mass 500 mg with a single irradiation of 4 hours and two sequences of counting. Our sensitivity for many of the trace elements is better than 1 ppm by weight under the conditions chosen. In this talk, details of our procedure, including quality assurance as measured by NIST standard reference materials, will be discussed. In addition, preliminary results from data treatment using cluster analysis will be presented. (author)

  19. The use of Usnea sp. and Tillandsia capillaries as biomonitors of environmental pollution in Lima city, Peru

    International Nuclear Information System (INIS)

    In order to evaluate pollution in the city of Lima, Peru, an environmental monitoring was carried out using two species of biomonitors: Liquen Usnea sp. and Tillandsia capillaries. Both samples were taken from an uncontaminated area to be exposed during three months in different sampling sites of the city. Then samples were collected, prepared and analyzed by instrumental neutron activation analysis, based k0 method. Results showed important contamination in East and North sites of the city coming from industrial activities and automotive vehicles emissions. (author).

  20. Multielement atmospheric deposition study in Croatia using moss biomonitoring, NAA, AAS and GIS technologies

    International Nuclear Information System (INIS)

    For the first time the moss biomonitoring technique and two complementary analytical techniques - neutron activation analysis (NAA) and atomic absorption spectrometry (AAS) - were applied to study multielement atmospheric deposition in the Republic of Croatia. Moss samples were collected during the summer 2006 from 98 sites evenly distributed over the country. Sampling was performed in accordance with the LRTAP Convention - ICP Vegetation protocol and sampling strategy of the European Programme on Biomonitoring of Heavy Metal Atmospheric Deposition. Conventional and epithermal neutron activation analyses made it possible to determine concentrations of 41 elements including key heavy metals such as Pb, Cd, Hg, and Cu determined by AAS. Principal component analysis (factor analysis with VARIMAX rotation) was applied to distinguish elements mainly of anthropogenic origin from those predominantly originating from natural sources. Geographical distribution maps of the elements over the sampled territory were constructed using GIS technology. The median values for Croatia are consistent with the corresponding values for all Europe for most elements. It was shown that the Adriatic coastline of Croatia may be considered as an environmentally pristine area. This study was conducted for providing reliable assessment of air quality throughout Croatia and producing information needed for better identification of pollution sources and improving the potential for assessing environmental and health risks in Croatia associated with toxic metals

  1. Activities induced in the human body by thermal neutrons

    International Nuclear Information System (INIS)

    Activities of 17 radionuclides induced in the human body by the activation of 14 elements with thermal neutrons were calculated. Resulting dependences of these activities on the activation time are shown in graphs. (author)

  2. Silicate rock and rock forming mineral neutron activation analysis

    International Nuclear Information System (INIS)

    A neutron-activation scheme for the determination of nine rare earths and other trace elements in various rock forming minerals (feldspars, ilmenite, magnetite, pyroxenes) and silicate rocks is presented. The procedure is based on three different irradiations involving three separate samples: - epithermal neutron irradiation (2 days) followed by nondestructive analysis; - thermal neutron irradiation (1 day) followed by instrumental analysis; - thermal neutron irradiation (1 week) followed by radiochemical analysis (precipitation, anion exchange separation, liquid-liquid extraction). Two USGS reference samples - granite G-2 and andesite AGV-1 - have been analysed in order to assess the accuracy of the proposed procedure. Our results agree with previous neutron-activation data. (orig.)

  3. Medical chemistry of boron neutron capture agents having pharmacological activity

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT) is a cancer treatment that selectively destroys cancer cells following administering a cancer-selective drug containing stable isotope boron-10 and neutron irradiation. In clinical trial of BNCT, disodium mercaptoundecahydro-closo-dodecaborate (BSH) and p-boronophenylalanine (BPA) have been used, however, development of a new drugs with high cancer selectivity and therapeutic efficiency is expected. Therefore, we review boron-containing drugs as a boron neutron capture agents having pharmacological activity, BNCT research on boron-modified porphyrin derivatives which have photosensitivity and neutron capture activity and our proposed neutron sensitizing agent. (author)

  4. Reactor neutron activation for multielemental analysis

    International Nuclear Information System (INIS)

    Neutron Activation Analysis using single comparator (K0 NAA method) has been used for obtaining multielemental profiles in a variety of matrices related to environment. Gold was used as the comparator. Neutron flux was characterised by determining f, the epithermal to thermal neutron flux ratio and cc, the deviation from ideal shape of the neutron spectrum. The f and a were determined in different irradiation positions in APSARA reactor, PCF position in CIRUS reactor and tray rod position in Dhruva reactor using both cadmium cut off and multi isotope detector methods. High resolution gamma ray spectrometry was used for radioactive assay of the activation products. This technique is being used for multielement analysis in a variety of matrices like lake sediments, sea nodules and crusts, minerals, leaves, cereals, pulses, leaves, water and soil. Elemental profiles of the sediments corresponding to different depths from Nainital lake were determined and used to understand the history of natural absorption/desorption pattern of the previous 160 years. Ferromanganese crusts from different locations of Indian Ocean were analysed with a view to studying the distribution of some trace elements along with Fe and Mn. Variation of Mn/Fe ratio was used to identify the nature of the crusts as hydrogenous or hydrothermal. Fe-rich and Fe-depleted nodules from Indian Ocean were analysed to understand the REE patterns and it is proposed that REE-Th associated minerals could be the potential Th contributors to the sea water and thus reached ferromanganese nodules. Dolomites (unaltered and altered), two types of serpentines and intrusive rock dolerite from the asbestos mines of Cuddapah basin were analysed for major, minor and trace elements. The elemental concentrations are used for distinguishing and characterising these minerals. From our investigations, it was concluded that both dolomite and dolerite contribute elements in the serpentinisation process. Chemical neutron

  5. Epithermal neutron activation analysis of food

    International Nuclear Information System (INIS)

    Food samples were irradiated with thermal and epithermal neutrons. The average ratios of thermal to epithermal activity were determined for 80Br, 49Ca, 38Cl, 60mCo, 42K, 27Mg, 56Mn, 24Na, and 86mRb. They were equal to 2.1, 26, 24, 6.6, 19, 16, 11, 23 and 1.9, respectively. Then, 57 food samples were analyzed by epithermal neutron activation analysis for Br and Rb. The concentrations (in ppm) of Br and Rb were in asparagus (2) 2.3, 11.5; beets (3) 0.5, 0.8; beef (3) 1.7, 3.6; cabbage (5) 0.5, 10.8; carrot (3) 0.2, 3.7; chicken (3) 0.6, 4.4; chocolate (7) 11.1, 18.7; egg (3) 0.9, 1.9; french bean (3) 0.3, 1.0; goose (2) 1.3, 9.3; lettuce (2) 0.9, 1.7; pork (1) 1.5, 4.4; potato (7) 1.0, 1.2; sausage (3) 4.8, 3.5; spinach (3) 3.6, 4.0; strawberry jam (3) 0.4, 1.4; tomato (1) 13.5, 14.6; turkey (3) 1.2, 4.9. respectively. The number of samples and analyzed is indicated in parentheses. (author)

  6. Measurement of neutron flux spectra in a tungsten benchmark by neutron foil activation method

    International Nuclear Information System (INIS)

    The nuclear designs of fusion devices such as ITER (international thermonuclear experimental reactor), which is an experimental fusion reactor based on the ''tokamak'' concept, rely on the results of neutron physical calculations. These depend on the knowledge of the neutron and photon flux spectra which is particularly important because it permits to anticipate the possible answers of the whole structure to phenomena such as nuclear heating, tritium breeding, atomic displacements, radiation shielding, power generation and material activation. The flux spectra can be calculated with transport codes, but validating measurements are also required. An important constituent of structural materials and divertor areas of fusion reactors is tungsten. This thesis deals with the measurement of the neutron fluence and neutron energy spectrum in a tungsten assembly by means of multiple foil neutron activation technique. In order to check and qualify the experimental tools and the codes to be used in the tungsten benchmark experiment, test measurements in the D-T and D-D neutron fields of the neutron generator at Technische Universitaet Dresden were performed. The characteristics of the D-D and D-T reactions, used to produce monoenergetic neutrons, together with the selection of activation reactions suitable for fusion applications and details of the activation measurements are presented. Corrections related to the neutron irradiation process and those to the sample counting process are discussed, too. The neutron fluence and its energy distribution in a tungsten benchmark, irradiated at the frascati neutron generator with 14 MeV neutrons produced by the T(d,n)4He reaction, are then derived from the measurements of the neutron induced γ-ray activity in the foils using the STAYNL unfolding code, based on the linear least-squares-errors method, together with the IRDF-90.2 (international reactor dosimetry file) cross section library. The differences between the neutron flux

  7. Characterization of inorganic constituents in leaves of Tradescantia pallida species by neutron activation analysis

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the element levels in T. pallida leaves, as well as, to establish appropriate experimental conditions for sampling and preparation the sample for the elemental analysis. Leaves of this plant species were collected in different sites of Sao Paulo state. The method of neutron activation analysis (NAA) was applied in the element determinations. To evaluate the accuracy and the precision of the results, a certified reference material INCT-MPH-2 Mixed Polish Herbs was analyzed. The results obtained in these analyses indicated good precision and agreement with the certified values. The relative errors and the relative standard deviations obtained were lower than 8.2% and 8.6%, respectively. Results obtained in the replicate analyses of T. pallida samples also presented good reproducibility indicating the homogeneity of the prepared sample. In the analyses of young and adult leaves separately, higher concentrations of most of the elements were found in adult leaves than those in young ones. A preliminary comparison made between the results obtained for T. pallida leaves collected in different sites indicated differences depending on the element. The results indicated a good precision with the relative standard deviations lower than 11.3%, except Br. The findings of this study indicated the possibility of using T. pallida in an active biomonitoring by exposure of this plant species cultivated in vases. (author)

  8. Selected industrial and environmental applications of neutron activation analysis

    International Nuclear Information System (INIS)

    A review of the applications of Instrumental Neutron Activation Analysis (INAA) in the industrial and environmental fields is given. Detection limits for different applications are also given. (author)

  9. Biomonitoring air pollution in Chile

    International Nuclear Information System (INIS)

    Full text: Chile, in general, and Santiago, its capital city, in particular, has serious air pollution problems mainly in winter time when the pollutants could reach dangerous levels which might be detrimental to older people and children. A project was undertaken within the framework of a Co-ordinated Research Programme (CRP) supported by the International Atomic Energy Agency (IAEA) to carry out a long term study on atmospheric air pollution in Chile using biomonitors. The present paper describes the activities carried out within this CRP. The lichens, collected in clean areas (native forests), were transplanted to selected sites in Santiago and exposed during three and six months. At a second stage, samples of Tillandsia recurvata were collected in the Metropolitan Area. All samples were carefully cleaned, using only clean plastic materials, milled at liquid nitrogen temperature, freeze dried, re-homogenized and stored at low temperature until analysis. The samples were mainly analysed by INAA, RNAA SS-AAS and ASV. As part of the routine QA/QC programme, analytical laboratories involved in the project participated in intercomparison runs organized by the IAEA for the determination of trace and minor elements in two lichens samples. From the data and its subsequent mapping over the area under study, it was possible to identify places exposed to higher amounts of some elements. Of interest are also the correlations between several elements, perhaps indicating a given source of pollutants. The results indicate the usefulness of biomonitoring air pollution using lichens and Tillandsias, which, jointly with multielemental analytical techniques, such as NAA, open the possibility to study extensive areas without the infrastructure needed for conventional APM sample collection and at reduced costs. (author)

  10. Air Pollution Studies in Opole Region, Poland, using the Moss Biomonitoring and INAA

    Science.gov (United States)

    Korzekwa, S.; Pankratova, Yu. S.; Frontasyeva, M. V.

    2007-11-01

    Biomonitoring of heavy metal atmospheric deposition with terrestrial moss is a well established technique for environmental studies. Moss samples of Hylocomium splendens and Pleurozium schreberi have been collected around the city of Opole. A total of 34 elements including heavy metals and rare earths have been determined by instrumental neutron activation analysis (INAA) using epithermal neutrons at the IBR-2 reactor of the Joint Institute for Nuclear Research. We observe pronounced contamination of the sampled area with pollutants such as As, Sb, V, Ni, Mo, etc. at levels similar to those in the neighboring industrial regions. These results evidences long-range atmospheric transport of pollutants along with the influence of local pollution sources.

  11. Activation Spectrometry of Fast Neutrons by IAEA Threshold Detectors at Neutron Generators

    International Nuclear Information System (INIS)

    The suitability of the IAEA set of threshold detectors for neutron accident purposes was investigated. A generator producing 14.3-MeV neutrons by the T(d, n)4He reaction was employed for this purpose. 237Np, 232Th, 58Ni and 27Al threshold detectors were used. The induced activity was determined by gamma spectrometry using a multichannel analyser. Fast neutron spectra have been estimated from the experimental results. Measurements at the surface and at the depth of a phantom were provided. Some difficulties from low induced and fission activities (caused by the small neutron flux density and the light weight of the detectors) are pointed out. (author)

  12. Estimation of thermal neutron flux from natZr activity

    International Nuclear Information System (INIS)

    Neutron transmutation doped (NTD) Ge thermistors are developed as low temperature thermometry (in mK range) in the cryogenic Tin bolometer, the India-based TIN detector (TIN.TIN). For this purpose, semiconductor grade Ge wafers are irradiated with thermal neutron at Dhruva reactor, BARC and dopant concentration critically depends on thermal neutron fluence. In order to obtain an independent estimate of the thermal neutron flux, natZr is used in one of the irradiations. The irradiated natZr samples have been studied in the Tifr Low background Experimental Setup (TiLES). The thermal neutron flux is estimated from the activity of 95Zr

  13. Industrial applications of neutron activation analysis

    International Nuclear Information System (INIS)

    Neutron activation analysis has been widely used in the industry and over the years played a key role in the development of manufacturing process as well as monitoring of the process flow. In this context NAA has been utilized both in R and D, and in the factory as a flexible analytical tool. It has been used successfully in numerous industries including broad categories such as Chemical, Pharmaceutical, Mining, Photographic, Oil and Gas, Automobile, Defense, Semiconductor and Electronic industries. Dow Chemical owns and operates a research reactor for analytical measurements of samples generated in both R and D, and manufacturing area in its plant in Midland, Michigan. Although most industries do not have reactors on their campus but use an off site reactor regularly, and often have in-house neutron sources such as a 252Cf used primarily for NAA. In most industrial materials analysis laboratory NAA is part of a number of analytical techniques such as ICP-MS, AA, SIMS, FTIR, XRF, TXRF etc. Analysis of complex industrial samples may require data from each of these methods to provide a clear picture of the materials issues involved. With the improvement of classical analytical techniques, and the introduction of new techniques, e.g. TXRF, the role of NAA continues to be a key bench mark technique that provides accurate and reliable data. The strength of the NAA in bulk analysis is balanced by its weakness in providing surface sensitive or spatially resolved analysis as is required by many applications. (author)

  14. Development of high flux thermal neutron generator for neutron activation analysis

    International Nuclear Information System (INIS)

    The new model DD110MB neutron generator from Adelphi Technology produces thermal (<0.5 eV) neutron flux that is normally achieved in a nuclear reactor or larger accelerator based systems. Thermal neutron fluxes of 3–5 · 107 n/cm2/s are measured. This flux is achieved using four ion beams arranged concentrically around a target chamber containing a compact moderator with a central sample cylinder. Fast neutron yield of ∼2 · 1010 n/s is created at the titanium surface of the target chamber. The thickness and material of the moderator is selected to maximize the thermal neutron flux at the center. The 2.5 MeV neutrons are quickly thermalized to energies below 0.5 eV and concentrated at the sample cylinder. The maximum flux of thermal neutrons at the target is achieved when approximately half of the neutrons at the sample area are thermalized. In this paper we present simulation results used to characterize performance of the neutron generator. The neutron flux can be used for neutron activation analysis (NAA) prompt gamma neutron activation analysis (PGNAA) for determining the concentrations of elements in many materials. Another envisioned use of the generator is production of radioactive isotopes. DD110MB is small enough for modest-sized laboratories and universities. Compared to nuclear reactors the DD110MB produces comparable thermal flux but provides reduced administrative and safety requirements and it can be run in pulsed mode, which is beneficial in many neutron activation techniques

  15. Computer modeling for neutron activation analysis methods

    International Nuclear Information System (INIS)

    Full text: The INP AS RU develops databases for the neutron-activation analysis - ND INAA [1] and ELEMENT [2]. Based on these databases, the automated complex is under construction aimed at modeling of methods for natural and technogenic materials analysis. It is well known, that there is a variety of analysis objects with wide spectra, different composition and concentration of elements, which makes it impossible to develop universal methods applicable for every analytical research. The modelling is based on algorithm, that counts the period of time in which the sample was irradiated in nuclear reactor, providing the sample's total absorption and activity analytical peaks areas with given errors. The analytical complex was tested for low-elemental analysis (determination of Fe and Zn in vegetation samples, and Cu, Ag and Au - in technological objects). At present, the complex is applied for multielemental analysis of sediment samples. In this work, modern achievements in the analytical chemistry (measurement facilities, high-resolution detectors, IAEA and IUPAC databases) and information technology applications (Java software, database management systems (DBMS), internet technologies) are applied. Reference: 1. Tillaev T., Umaraliev A., Gurvich L.G., Yuldasheva K., Kadirova J. Specialized database for instrumental neutron activation analysis - ND INAA 1.0, The 3-rd Eurasian Conference Nuclear Science and its applications, 2004, pp.270-271.; 2. Gurvich L.G., Tillaev T., Umaraliev A. The Information-analytical database on the element contents of natural objects. The 4-th International Conference Modern problems of Nuclear Physics, Samarkand, 2003, p.337. (authors)

  16. Large sample neutron activation analysis of a ceramic vase

    OpenAIRE

    Stamatelatos, I.E.; Tzika, F.; Vasilopoulou, T.; Koster-Ammerlaan, M.J.J.

    2010-01-01

    Large Sample Neutron Activation Analysis (LSNAA) was applied to perform non-destructive elemental analysis of a ceramic vase. Appropriate neutron self-shielding and gamma ray detection efficiency calibration factors were derived using Monte Carlo code MCNP5. The results of LSNAA were compared against Instrumental Neutron Activation Analysis (INAA) results and a satisfactory agreement between the two methods was observed. The ratio of derived concentrations between the two methods was within 0...

  17. Neutron activation of gold dental restorations in small primates

    Energy Technology Data Exchange (ETDEWEB)

    Zellmer, R.W.; Hartley, J.L.; Richey, E.O.; Harris, N.O.

    1959-07-01

    Dental gold alloys of various kinds were used to cast inlays which were placed in the molars of 10 small primates. These primates were then exposed to the neutron flux of an atomic detonation. The inlays were removed and the neutron-induced activity of the gold was measured in a scintillation counter. Calculation of the total activity showed a correlation with the neutron dosages received by the primates.

  18. Improved Fission Neutron Data Base for Active Interrogation of Actinides

    Energy Technology Data Exchange (ETDEWEB)

    Pozzi, Sara; Czirr, J. Bart; Haight, Robert; Kovash, Michael; Tsvetkov, Pavel

    2013-11-06

    This project will develop an innovative neutron detection system for active interrogation measurements. Many active interrogation methods to detect fissionable material are based on the detection of neutrons from fission induced by fast neutrons or high-energy gamma rays. The energy spectrum of the fission neutrons provides data to identify the fissionable isotopes and materials such as shielding between the fissionable material and the detector. The proposed path for the project is as follows. First, the team will develop new neutron detection systems and algorithms by Monte Carlo simulations and bench-top experiments. Next, They will characterize and calibrate detection systems both with monoenergetic and white neutron sources. Finally, high-fidelity measurements of neutron emission from fissions induced by fast neutrons will be performed. Several existing fission chambers containing U-235, Pu-239, U-238, or Th-232 will be used to measure the neutron-induced fission neutron emission spectra. The challenge for making confident measurements is the detection of neutrons in the energy ranges of 0.01 – 1 MeV and above 8 MeV, regions where the basic data on the neutron energy spectrum emitted from fission is least well known. In addition, improvements in the specificity of neutron detectors are required throughout the complete energy range: they must be able to clearly distinguish neutrons from other radiations, in particular gamma rays and cosmic rays. The team believes that all of these challenges can be addressed successfully with emerging technologies under development by this collaboration. In particular, the collaboration will address the area of fission neutron emission spectra for isotopes of interest in the advanced fuel cycle initiative (AFCI).

  19. Neutron activation in EBT-P

    International Nuclear Information System (INIS)

    Neutron activation due to photoneutron production in the lead shields proposed to protect the EBT-P superconducting coils from excessive x-ray heating was investigated. The photoneutron flux distribution in various EBT-P structural components was calculated for typical upgrade operating conditions using a standard two-dimensional transport model (TWOTRAN). Activity levels were then evaluated for major structural materials using activation cross sections tabulated in the GAMMON library. Activation dose rates in the device enclosure following several days of 8h/day upgrade (90GHz) operation were found to be approx. 6 mrem/h, decaying to <0.25 mrem/h in approx. 3 days. This requires radiation monitoring of all personnel entering the device enclosure during this time, but should not generally restrict hands on access to the device. There is thus no strong motivation to replace lead with another shield material; however, it may be desirable to borate the enclosure walls in order to reduce the effect which impurities might have on activity levels

  20. Neutron Activation Analysis of Biological Materials by Means of Neutron Multiplicator

    International Nuclear Information System (INIS)

    We have studied the possibilities of instrumental neutron activation analysis of freeze-dried biological materials performed with neutron multiplicator of average power (subcritical assembly PS-1). Neutron flux in the vertical channel amounts to 2.3*106n/cm2sec, concentrations of Na, Al and Mn were determined in freeze-dried samples of blue-green alga Spirulina platensis (S.platensis) (author)

  1. Neutron activation analysis at the service of the worker's health: determination of arsenic

    International Nuclear Information System (INIS)

    Exposures in the workplace are generally registered when there are easily identified diseases. The major problem is that most workers are exposed to low levels of toxic chemicals that can be lethal after a long period of time, due to chronic diseases. Aiming at giving support to the Worker's Health Awareness Program of the Municipal Department of Health of Belo Horizonte, an assessment was carried out in three galvanising factories by means of airborne particulate matter collected in air filters and hair and toenail samples as biomonitors. The arsenic was determined in all matrixes from factories where gold electrodeposition process was applied. This is because arsenic salts are usually added to gold bath to improve the metal covering. The high concentration results surprised the health surveillance professionals, and alerted for the need of assessing the influence of a long-term exposure. Studies concerning galvanising process have usually been developed broaching many aspects, but so far none has pointed out the detection and measurement of other elements like arsenic. The results will support the establishment of guidelines and data basis for the next occupational program for this specific workplace. The k0-Instrumental Neutron Activation method was applied confirming to be a suitable technique on determination of arsenic in diversified matrixes. (author)

  2. Comparison of activation in fission and fusion spectrum neutron beams

    International Nuclear Information System (INIS)

    The materials used in the construction of fusion reactors have to satisfy a number of criterions, one of the important being low activation due to neutron irradiation. Experimental analysis of the activation of candidate materials for the first wall is performed with the irradiation of samples in various neutron fields, frequently in the field of a fission reactor. In the present work a calculation is performed to compare the expected activation of candidate materials intended to be used for the first wall in fusion reactors with the activation of a sample of the same material in a fission reactor beam. The FISPACT code is used for activation calculations. An investigation, to what extent the results of activation in a fission spectrum neutron beam, where most neutrons have energies of less than 2 MeV, mimic the real situation in a fusion reactor with the peak neutron energy around 14 MeV, is performed. (author)

  3. Instrumental neutron activation analysis of soil sample

    International Nuclear Information System (INIS)

    This paper describes the analysis of soil samples collected from 5 different location around Sungai Lui, Kajang, Selangor, Malaysia. These sample were taken at 22-24 cm from the top of the ground and were analysed using the techniques of Instrumental Neutron Activation Analysis (INAA). The analysis on soil sample taken above 22-24 cm level were done in order to determine if there is any variation in elemental contents at different sampling levels. The results indicate a wide variation in the contents of the samples. About 30 elements have been analysed. The major ones are Na, I, Cl, Mg, Al, K, Ti, Ca and Fe. Trace elements analysed were Ba, Sc, V, Cr, Mn, Ga, As, Zn, Br, Rb, Co, Hf, Zr, Th, U, Sb, Cs, Ce, Sm, Eu, Tb, Dy, Yb, Lu and La. (author)

  4. Neutron activation analysis of urinary calculi

    International Nuclear Information System (INIS)

    Urinary calculi resulting from disorders in the urinary system are mostly composed of uric acid, urates, calcium oxalate, alkaline earth phosphates (Ca and Mg), triple phosphate (magnesium ammonium phosphate), calcium carbonate, cystine, xanthine, and traces of proteins. The determination of these macro-constituents has been carried out by different analytical procedures. No attempts however, have been reported regarding the determination of trace elements in urinary stones, apart from that of Herring et al., who investigated the consumption of strontium by urolithiasis patients. The present work is a non-destructive neutron activation analysis of urinary calculi, to search the variation in concentration of certain trace elements with the chemical composition of the calculus

  5. Neutron activation analysis of human hair

    International Nuclear Information System (INIS)

    In an attempt to study the availability and limitation of analytical data of human hair as an indicator of environmental pollution and/or of human health effect, concentrations of elements in 202 scalp hair samples collected from local population in the Tokyo Metropolitan area were determined by instrumental neutron activation analysis. The correlation coefficients between concentrations of 13 elements in each sex and in each age group were calculated and discussed. There were significant correlations between some pairs of elements, i.e. Na-K, Br-Cl, Ca-Zn and Ca-Mg, in all five age classes in both of male and female, indicating that the correlations were consistent. Ca was observed to be reversely correlated with Cl. No significant correlation was apparent between Hg and Se, when the correlation coefficient was calculated using logarithmic converted concentration data. (author)

  6. Instrumental neutron activation analysis of kidney stones

    International Nuclear Information System (INIS)

    Kidney stone samples of the types calcium oxalate, uric acid, and xanthine were analyzed for their elemental contents by neutron activation analysis to study both the elemental correlation and influence of element on stone precipitation processes. Elements, such as Al, Au, Br, Ca, Cl, Co, Cr, Fe,H, I, K, Mg, Na, Sb, Se, Sr, and Zn, were determined quantitatively. Calcium oxalate stones contained higher concentration of all the elements analyzed compared to uric acid or xanthine stones. The concentrations of Cl, Fe, K, Na, Sr, and Zn were relatively higher than Au, Co, Cr, and Sb. A positive correlation exists between Ca and Zn, whereas a negative correlation exists between Sr and Ca. Zinc may play an important role in the formation of calcium oxalate stone

  7. Measurements of fusion neutron yields by neutron activation technique: Uncertainty due to the uncertainty on activation cross-sections

    International Nuclear Information System (INIS)

    The neutron activation technique is routinely used in fusion experiments to measure the neutron yields. This paper investigates the uncertainty on these measurements as due to the uncertainties on dosimetry and activation reactions. For this purpose, activation cross-sections were taken from the International Reactor Dosimetry and Fusion File (IRDFF-v1.05) in 640 groups ENDF-6 format for several reactions of interest for both 2.5 and 14 MeV neutrons. Activation coefficients (reaction rates) have been calculated using the neutron flux spectra at JET vacuum vessel, both for DD and DT plasmas, calculated by MCNP in the required 640-energy group format. The related uncertainties for the JET neutron spectra are evaluated as well using the covariance data available in the library. These uncertainties are in general small, but not negligible when high accuracy is required in the determination of the fusion neutron yields

  8. Chemical weapons detection by fast neutron activation analysis techniques

    International Nuclear Information System (INIS)

    A neutron diagnostic experimental apparatus has been tested for nondestructive verification of sealed munitions. Designed to potentially satisfy a significant number of van-mobile requirements, this equipment is based on an easy to use industrial sealed tube neutron generator that interrogates the munitions of interest with 14 MeV neutrons. Gamma ray spectra are detected with a high purity germanium detector, especially shielded from neutrons and gamma ray background. A mobile shell holder has been used. Possible configurations allow the detection, in continuous or in pulsed modes, of gamma rays from neutron inelastic scattering, from thermal neutron capture, and from fast or thermal neutron activation. Tests on full scale sealed munitions with chemical simulants show that those with chlorine (old generation materials) are detectable in a few minutes, and those including phosphorus (new generation materials) in nearly the same time. (orig.)

  9. Development of educational program for neutron activation analysis

    International Nuclear Information System (INIS)

    This technical report is developed to apply an educational and training program for graduate student and analyst utilizing neutron activation analysis. The contents of guide book consists of five parts as follows; introduction, gamma-ray spectrometry and measurement statistics, its applications, to understand of comprehensive methodology and to utilize a relevant knowledge and information on neutron activation analysis

  10. Trace Analysis of Ancient Gold Objects Using Radiochemical Neutron Activation

    CERN Document Server

    Olariu, A; Constantinescu, O; Badica, T; Popescu, I V; Besliu, C; Leahu, D; Olariu, Agata; Constantinescu, Mioara; Leahu, Doina

    1999-01-01

    Radiochemical neutron activation analysis has been applied to investigate the microelements in gold samples with archaeological importance. Chemical separation has allowed the determination of traces of Ir, Os, Sb, Zn, Co, Fe, Ni. Instrumental neutron activation analysis has been used for the determination of Cu.

  11. Development of educational program for neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Yong Sam; Moon, Jong Hwa; Kim, Sun Ha; Ryel, Sung; Kang, Young Hwan; Lee, Kil Yong; Yeon, Yeon Yel; Cho, Seung Yeon

    2000-08-01

    This technical report is developed to apply an educational and training program for graduate student and analyst utilizing neutron activation analysis. The contents of guide book consists of five parts as follows; introduction, gamma-ray spectrometry and measurement statistics, its applications, to understand of comprehensive methodology and to utilize a relevant knowledge and information on neutron activation analysis.

  12. Determination of average activating thermal neutron flux in bulk samples

    International Nuclear Information System (INIS)

    A previous method used for the determination of the average neutron flux within bulky samples has been applied for the measurements of hydrogen contents of different samples. An analytical function is given for the description of the correlation between the activity of Dy foils and the hydrogen concentrations. Results obtained by the activation and the thermal neutron reflection methods are compared

  13. Active Neutron Interrogation and Delayed Neutron Counting (AIDNEC) for assay of 235U

    International Nuclear Information System (INIS)

    A method has been developed for non destructive assay of 235U using active neutron interrogation followed by delayed neutron counting (AIDNEC) system. The neutrons from a plasma focus (PF) device were used to bombard the samples containing low enriched uranium ranging from 13 mg to 5 g. The PF device generates (1.2±0.3) x109 D-D fusion neutrons per shot with a pulse width of 46±5 ns. The delayed neutrons were monitored using a bank of six 3He detectors. The sensitivity of the system was found to be about 1000 cps per gram over the accumulation time of 25 seconds per neutron pulse of ∼109. The detection limit of the system is estimated to be 18 mg of 235U. (author)

  14. Design of a prompt gamma neutron activation analysis system and neutron beam characteristics at HANARO

    International Nuclear Information System (INIS)

    The design features and neutron beam characteristics are described for a prompt gamma neutron activation analysis(PGNAA) system at HANARO in Korea Atomic Energy Research Institute(KAERI). As a method to obtain clean beam of thermal neutrons, Bragg diffraction technique of using PG crystal is applied. The Bragg angle is set at 45 .deg. and the diffracted beam is a polychromatic one composed of neutrons from all diffraction orders n(≤n≤6). The fast neutron and gamma backgrounds will be low enough due to the use of diffracted beam and a tapered collimator. A neutron flux of 1.0x108 n/cm2sec is calculated at sample position by considering the reflectivity of PG crystal. The γ-ray detection system is comprised of a 30% n-type HPGe detector, signal electronics and a fast ADC. Construction of the beam line and setting up of the detection system is proceeding

  15. Neutron activation diagnostics at the National Ignition Facility (invited).

    Science.gov (United States)

    Bleuel, D L; Yeamans, C B; Bernstein, L A; Bionta, R M; Caggiano, J A; Casey, D T; Cooper, G W; Drury, O B; Frenje, J A; Hagmann, C A; Hatarik, R; Knauer, J P; Johnson, M Gatu; Knittel, K M; Leeper, R J; McNaney, J M; Moran, M; Ruiz, C L; Schneider, D H G

    2012-10-01

    Neutron yields are measured at the National Ignition Facility (NIF) by an extensive suite of neutron activation diagnostics. Neutrons interact with materials whose reaction cross sections threshold just below the fusion neutron production energy, providing an accurate measure of primary unscattered neutrons without contribution from lower-energy scattered neutrons. Indium samples are mounted on diagnostic instrument manipulators in the NIF target chamber, 25-50 cm from the source, to measure 2.45 MeV deuterium-deuterium fusion neutrons through the (115)In(n,n')(115 m) In reaction. Outside the chamber, zirconium and copper are used to measure 14 MeV deuterium-tritium fusion neutrons via (90)Zr(n,2n), (63)Cu(n,2n), and (65)Cu(n,2n) reactions. An array of 16 zirconium samples are located on port covers around the chamber to measure relative yield anisotropies, providing a global map of fuel areal density variation. Neutron yields are routinely measured with activation to an accuracy of 7% and are in excellent agreement both with each other and with neutron time-of-flight and magnetic recoil spectrometer measurements. Relative areal density anisotropies can be measured to a precision of less than 3%. These measurements reveal apparent bulk fuel velocities as high as 200 km/s in addition to large areal density variations between the pole and equator of the compressed fuel. PMID:23126840

  16. Layered shielding design for an active neutron interrogation system

    Science.gov (United States)

    Whetstone, Zachary D.; Kearfott, Kimberlee J.

    2016-08-01

    The use of source and detector shields in active neutron interrogation can improve detector signal. In simulations, a shielded detector with a source rotated π/3 rad relative to the opening decreased neutron flux roughly three orders of magnitude. Several realistic source and detector shield configurations were simulated. A layered design reduced neutron and secondary photon flux in the detector by approximately one order of magnitude for a deuterium-tritium source. The shield arrangement can be adapted for a portable, modular design.

  17. Transmission and Reflection of Neutrons Using Foil Activation Technique

    International Nuclear Information System (INIS)

    A new neutron irradiation facility has been designed, constructed .and located at the Experimental Nuclear Physics Department, NRC, AEA, cairo. The neutrons were obtained from CNIF2 (Second Cairo Neutron Irradiation Facility) that is based on one 241 Am-Be(α, n) isotopic neutron source with a present activity of about 175 GBq results in a neutron yield of about 1.04 x107 n/s. The geometrical arrangements of the facility consider the safety and protection rules aspects. MCNP5 code is used to estimate radiation doses and neutron fluxes. This new irradiation facility provides fast and epithermal neutrons that can be used in basic research and industrial applications. The aim of the present work is to study the characteristics of this new irradiation facility and to develop methods able to use fast and epithermal neutron in some different applications. Experimental measurements for the transmission and reflection of neutrons were carried out via a number of hydrogenous materials using the activation foil technique. A comparison of the experimental results with that calculated by using Monte Carlo simulation method is presented Using the neutron transmission technique in combination with foil activation method, our arrangement is used to measure the total neutron microscopic cross-sections for some compounds. The facility is calibrated and suitable to estimate the hydrogen content H (wt %) and the weight ratios C/H in hydrocarbon materials and was used to measure these ratios for some Egyptian crude oil samples. A brief overview of the neutron activation analysis methods for elemental concentrations in bulk samples in natural conditions is presented.

  18. Measurement of 14.8 MeV neutron flux of a neutron generator using neutron activation technique

    International Nuclear Information System (INIS)

    Fast neutron flux (14.8 MeV) of a neutron generator has been measured by activation technique. The measurements performed using Cu and Ni threshold detectors. 62Cu and 57Ni were produced through 63Cu(n,2n)62Cu and 58Ni (n,2n)57Ni reactions. They decay by emitting 511 keV and 1377 keV gamma rays. respectively. The half life of 62Cu is 9.74min and that of 57Ni is 36 hours. The flux of neutron has been calculated by measuring the activity after the irradiation time. Gamma spectroscopy of the activated foils was performed using a HPGe detector. By employing this technique the neutron flux of 2.64 107±3% n/s was obtained for 60 μA deuteron of 110 keV energy, bombarding a solid target of 3H

  19. US Fish and Wildlife Service lands biomonitoring operations manual

    Energy Technology Data Exchange (ETDEWEB)

    Rope, R.C.; Breckenridge, R.P.

    1993-08-01

    This is Volume 1 of an operations manual designed to facilitate the development of biomonitoring strategies for U.S. Fish and Wildlife Service Lands. It is one component of the U.S. Fish and Wildlife Service Lands Biomonitoring Operations Manual. The Volume contains the Introduction to the Manual, background information on monitoring, and procedures for developing a biomonitoring strategy for Service lands. The purpose of the Biomonitoring Operations Manual is to provide an approach to develop and implement biomonitoring activities to assess the status and trends of U.S. Fish and Wildlife Service trust resources. It also provides field sampline methods and documentation protocols for contaminant monitoring activities. The strategy described in the Manual has been designed as a stand alone process to characterize the presence of contaminants on lands managed by the Service. This process can be sued to develop a monitoring program for any tract of real estate with potential threats from on- or off-site contaminants. Because the process was designed to address concerns for Service lands that span the United States from Alaska to the Tropical Islands, it has a generic format that can be used in al types of ecosystems, however, significant site specific informtion is required to complete the Workbook and make the process work successfully.

  20. Analysis by neutron activation in moss samples for the determination of Cr, Se, As and Hg; Analisis por activacion neutronica en muestras de musgos para la determinacion de Cr, Se, As y Hg

    Energy Technology Data Exchange (ETDEWEB)

    Mejia C, R.; Garcia R, G. [Instituto Tecnologico de Toluca, Departamento de Posgrado, Av. Tecnologico s/n, Fraccionamiento La Virgen, 52149 Metepec, Estado de Mexico (Mexico); Lopez R, C.; Avila P, P.; Longoria G, L. C., E-mail: rosario.mejia@inin.gob.mx [ININ, Departamento del Reactor, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2012-10-15

    This research work, presents a study of environmental monitoring in the Metropolitan Area of Toluca Valley using as bio-monitors to the mosses (bryophytes) native of different sites, analyzing the concentrations of As, Cr, Hg and Se, present in its structure. The analysis technique used to identify and to quantify to these elements was the Analysis by Neutron Activation, a nuclear analytic technique that allowed determining the concentrations at track level for its great versatility. Likewise the morphological study of the bryophyte Leskea angustata is presented by scanning electron microscopy. (Author)

  1. Neutron activation analysis of arsenic in Greece

    International Nuclear Information System (INIS)

    Arsenic is considered a toxic trace element for plant, animal, and human organisms. Arsenic and certain arsenic compounds have been listed as carcinogens by the U.S. Environmental Protection Agency. Arsenic is emitted in appreciable quantities into the atmosphere by coal combustion and the production of cement. Arsenic enters the aquatic environment through industrial activities such as smelting of metallic ores, metallurgical glassware, and ceramics as well as insecticide production and use. Neutron activation analysis (NAA) is a very sensitive, precise, and accurate method for determining arsenic. This paper is a review of research studies of arsenic in the Greek environment by NAA performed at our radioanalytical laboratory. The objectives of these studies were (a) to determine levels of arsenic concentrations in environmental materials, (b) to pinpoint arsenic pollution sources and estimate the extent of arsenic pollution, and (c) to find out whether edible marine organisms from the gulfs of Greece receiving domestic, industrial, and agricultural wastes have elevated concentrations of arsenic in their tissues that could render them dangerous for human consumption

  2. Neutron activation analysis of ancient silver coins

    International Nuclear Information System (INIS)

    The amounts of gold and copper present as impurities in 500 Creek silver coins of the fifth century B.C. have been determined with a gamma-ray spectrometer, following neutron activation. The coinage from eight cities and kingdoms was studied; the average gold-content for different groups of coins varies between 0.02% and 0.3%, and the copper content between 0.1% and 10%. Evidence about trading connexions and of deliberate debasements of the coinage has been obtained, and several unsuspected plated coins were detected. The gold content was determined by measuring the intensity of the 0.411 MeV gamma-ray from Au198 (2.69 d); for the copper content the 0.511 MeV positron annihilation radiation from Cu64 (12.8 h) was used, and for silver the 0.884 MeV gamma-ray from Ag110m (253 d). Decay measurements were used as a check of identity. The technique of using total gamma-activity decay curves by themselves is insufficiently sensitive. For accurate work, the importance of approximate facsimile standards is stressed. (author)

  3. Neutron activation analysis of human hair

    International Nuclear Information System (INIS)

    As a part of IAEA research project, ''Activation analysis of hair as an indicator of contamination of man by environmental trace element pollutants'', a survey was carried out to elucidate the levels of various trace element concentration in hair of local population in the Tokyo Metropolitan areas, by applying instrumental neutron activation analysis. A total of 202 scalp hair samples were collected from the inhabitants classified by sex and five age classes. Irradiation was made in the Rikkyo University 100 kW TRIGA MARK-II reactor. Using several combinations of irradiation time, cooling time and counting time, forty elements were determined. The relationship between several trace element contents in hair and such factors as sex, age class, hair treatment, smoking habit and dental treatment, was analyzed by using the method of multiple regression. It was shown that (1) Hair treatment had a predominant effect on the contents of bromine, magnesium and calcium in hair, (2) Aging and amoking contributed increasing mercury content in hair, and hair treatment acted reversely. (author)

  4. Fast neutron activation analysis of ancient mirror

    International Nuclear Information System (INIS)

    About fifty specimens of ancient Chinese bronze mirror from various dynasties are analysed by fast neutron radiated from neutron generator. The contents of copper, tin and lead in the mirror are listed in this paper. Experimental method and measurement equipment are described too

  5. Neutron activation analysis (NAA), radioisotope production via neutron activation (PNA) and fission product gas-jet (GJA)

    Energy Technology Data Exchange (ETDEWEB)

    Gaeggeler, H.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1996-11-01

    Three different non-diffractive applications of neutrons are outlined, neutron activation analysis, production of radionuclides, mostly for medical applications, and production of short-lived fission nuclides with a so-called gas-jet. It is shown that all three devices may be incorporated into one single insert at SINQ due to their different requests with respect to thermal neutron flux. Some applications of these three facilities are summarized. (author) 3 figs., 1 tab., 8 refs.

  6. Biomonitoring plan for Seedskadee National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This proposed biomonitoring plan is for Seedskadee National Wildlife Refuge in Sweetwater county, Wyoming. Biomonitoring is needed for the refuge especially due to...

  7. Neutron activation analysis at the Californium User Facility for Neutron Science

    International Nuclear Information System (INIS)

    The Californium User Facility (CUF) for Neutron Science has been established to provide 252Cf-based neutron irradiation services and research capabilities including neutron activation analysis (NAA). A major advantage of the CUF is its accessibility and controlled experimental conditions compared with those of a reactor environment The CUF maintains the world's largest inventory of compact 252Cf neutron sources. Neutron source intensities of ≤ 1011 neutrons/s are available for irradiations within a contamination-free hot cell, capable of providing thermal and fast neutron fluxes exceeding 108 cm-2 s-1 at the sample. Total flux of ≥109 cm-2 s-1 is feasible for large-volume irradiation rabbits within the 252Cf storage pool. Neutron and gamma transport calculations have been performed using the Monte Carlo transport code MCNP to estimate irradiation fluxes available for sample activation within the hot cell and storage pool and to design and optimize a prompt gamma NAA (PGNAA) configuration for large sample volumes. Confirmatory NAA irradiations have been performed within the pool. Gamma spectroscopy capabilities including PGNAA are being established within the CUF for sample analysis

  8. Neutron spectrum determination by activation method in fast neutron fields at the RB reactors

    International Nuclear Information System (INIS)

    The fast neutron fields of the RB reactor are presented in this paper. The activation method for spectrum determination is described and explained. The obtained results for intermediate and fast spectrum are given and discussed. (authors). 7 refs., 3 tabs

  9. Progress in small angle neutron scattering activities in Malaysia

    International Nuclear Information System (INIS)

    Research activities by use of small angle neutron scattering in Malaysia are briefly reported. Scattered neutron data are displayed in two or three-dimensional isometric view by the data acquisition system. Visual Basic is utilized for data acquisition and MathCad for data processing and analyses. (Y. Kazumata)

  10. Ten year's activity in the field of neutron scattering workshop

    International Nuclear Information System (INIS)

    'Neutron scattering' is in the frame of the 'Utilization of Research Reactor's of the FNCA (Forum for Nuclear Cooperation in Asia) project, which held the workshops from FY 1992. This report is a summary of the results and activities of neutron scattering workshops and sub-workshops since the start in FY 1992. (author)

  11. A synopsis of the activities on neutron standard reference data at the Institute of Atomic Energy

    International Nuclear Information System (INIS)

    The activities of neutron standard reference data including neutron standard cross section measurements, 252Cf spontaneous fission nubar and neutron energy spectrum measurements, neutron flux measurements, neutron source strength calibrations and neutron standard data evaluations carried out at the Institute of Atomic Energy, Beijing are presented. Some experimental results and recommended values are given

  12. Substoichiometric neutron activation determination of gold

    International Nuclear Information System (INIS)

    A highly precise and selective method is described for the determination of traces of gold by substoichiometric extraction from hydrochloric acid with tri-n-octylphosphine sulfide in cyclohexane following thermal neutron activation. Fundamental aspects of the extraction system are discussed and results are reported for the determination of gold in an effluent from a recovery process containing a complexed species of gold and unknown amounts of cyanide, citrate, phosphate, potassium and sodium. Other constituents of the effluent stream include traces of the transition elements Co, Ni, Fe, Cu, Zn, Pb and Sn at concentrations less than 50 ppm. One hour was allowed for the Au3+ carrier and the 198Au complexed species in samples and standards to oxidize, exchange, and reach chemical equilibrium. Samples were then equilibrated by shaking with the organic phase for thirty min. The percentage extractions (%E) for the substoichiometric separation of gold from the effluent and from the corresponding comparison standards were monitored. The mean percentage extractions for the substoichiometric separations of carrier from the effluent, and its corresponding standard were 75.3 and 59.3, respectively. These data are estimated to be accurate within +-2.0%. (T.G.)

  13. Chart of nuclides relating to neutron activation

    International Nuclear Information System (INIS)

    This chart is for frequent use in the prediction of the product species of neutron activation. The first edition of the chart has been made in 1976 after the repeated trial preparation. It has the following good points. (1) Any letter in chart is as large as one can read easily. [This condition has been obtained by the selection of items to be shown in chart. They are the name (the symbol of element, mass number, and half-life) of nuclide or of isomer, and the type of decay.]. (2) Decay product has been shown indirectly for branchings with two-step decay via short-lived daughter in an excited state. [This matter has been realized by use of the new mode of indication.] (3) Nuclides shown in chart are (a) naturally occurring nuclides and (b) nuclides formed from naturally occurring nuclides through one of the following reactions: (n, γ), (n, n'), (n, p), (n, α), (n, 2n), (n, pn), (n, 3n), (n, αn), (n, t), (n, 3He), (n, 2p), and (n, γ)(n, γ). In the revision of the first edition, some modes of indication have become a little simpler, and the isomers of shorter half-lives (0.1 - 1 μs) have been added. (author)

  14. Quality assurance in neutron activation analysis

    International Nuclear Information System (INIS)

    As a potential reference method, neutron activation analysis does not have to rely on other reference materials to ascertain the quality of analytical results. The fundamental characteristics of the method with the clear separation between irradiation, processing, and counting makes possible the estimation of uncertainties of individual results from a priori assumptions. Such estimates of the standard deviation from a series of independent sources of variation are compared with the a posteriori variability of replicate determinations in order to ascertain that the analytical method is in a state of statistical control. This Analysis of Precision tests the absence of unknown errors by means of a statistic T, which is closely approximated by a chi-square distribution. In this manner an evaluation is made of a commercially available computer program for peak evaluation in γ-spectrometry, as well as of other factors affecting the precision and accuracy of the counting process. An attempt is also made to determine sampling constants of one gram or less in a candidate biological reference material

  15. Epithermal neutron activation analysis in applied microbiology

    International Nuclear Information System (INIS)

    Some results from applying epithermal neutron activation analysis at FLNP JINR, Dubna, Russia, in medical biotechnology, environmental biotechnology and industrial biotechnology are reviewed. In the biomedical experiments biomass from the blue-green alga Spirulina platensis (S. platensis) has been used as a matrix for the development of pharmaceutical substances containing such essential trace elements as selenium, chromium and iodine. The feasibility of target-oriented introduction of these elements into S. platensis biocomplexes retaining its protein composition and natural beneficial properties was shown. The absorption of mercury on growth dynamics of S. platensis and other bacterial strains was observed. Detoxification of Cr and Hg by Arthrobacter globiformis 151B was demonstrated. Microbial synthesis of technologically important silver nanoparticles by the novel actinomycete strain Streptomyces glaucus 71 MD and blue-green alga S. platensis were characterized by a combined use of transmission electron microscopy, scanning electron microscopy and energy-dispersive analysis of X-rays. It was established that the tested actinomycete S. glaucus 71 MD produces silver nanoparticles extracellularly when acted upon by the silver nitrate solution, which offers a great advantage over an intracellular process of synthesis from the point of view of applications. The synthesis of silver nanoparticles by S. platensis proceeded differently under the short-term and long-term silver action. (author)

  16. Neutron-activation analysis of plant materials

    International Nuclear Information System (INIS)

    The possibilities offered by non-destructive neutron activation analysis (NAA) for simultaneously determining a large number of micro- and macro-components in plant samples of Bulgarian origin have been studied. Three groups of elements are determined: short half-life isotopes: Al, Mg, Ca, Na, Mn, Cl, Cu; medium half-life isotopes: Br, Na, K; and long half-life isotopes: Fe, Cr, Co, Sc, Pb, Zn. The samples are kept for 1 minute in a fluxes of 6x1012 n.cm2.sec-1 (first group), and of 3x1011 n.cm2.sec-1 for 18 hours (second and third groups). Use is made of a Ge/Li detector and 4000-channel analyser. To test the accuracy of the method, the results of NAA for some standard specimens have been compared with the indicators of other conventional methods tested in 18 laboratories in various countries. The data from NAA for the content of K, Mo, Ca, Mn, Fe, Zn and Cu demonstrate a high degree of coincidence with those from the other methods. Chemical composition of 23 samples of experimental and field crops is determined

  17. Active neutron multiplicity counting of bulk uranium

    International Nuclear Information System (INIS)

    This paper describes a new nondestructive assay technique being developed to assay bulk uranium containing kilogram quantities of 235U. The new technique uses neutron multiplicity analysis of data collected with a coincidence counter outfitted with AmLi neutron sources. We have calculated the expected neutron multiplicity count rate and assay precision for this technique and will report on its expected performance as a function of detector design characteristics, 235U sample mass, AmLi source strength, and source-to-sample coupling. 11 refs., 2 figs., 2 tabs

  18. The synchronous active neutron detection system for spent fuel assay

    International Nuclear Information System (INIS)

    The authors have begun to develop a novel technique for active neutron assay of fissile material in spent nuclear fuel. This approach will exploit the unique operating features of a 14-MeV neutron generator developed by Schlumberger. This generator and a novel detection system will be applied to the direct measurement of the fissile material content in spent fuel in place of the indirect measures used at present. The technique they are investigating is termed synchronous active neutron detection (SAND). It closely follows a method that has been used routinely in other branches of physics to detect very small signals in the presence of large backgrounds. Synchronous detection instruments are widely available commercially and are termed open-quotes lock-inclose quotes amplifiers. The authors have implemented a digital lock-in amplifier in conjunction with the Schlumberger neutron generator to explore the possibility of synchronous detection with active neutrons. This approach is possible because the Schlumberger system can operate at up to a 50% duty factor, in effect, a square wave of neutron yield. The results to date are preliminary but quite promising. The system is capable of resolving the fissile material contained in a small fraction of the fuel rods in a cold fuel assembly. It also appears to be quite resilient to background neutron interference. The interrogating neutrons appear to be nonthermal and penetrating. Although a significant amount of work remains to fully explore the relevant physics and optimize the instrument design, the underlying concept appears sound

  19. A dosimetry study of deuterium-deuterium neutron generator-based in vivo neutron activation analysis

    Science.gov (United States)

    Sowers, Daniel A.

    A neutron irradiation cavity for in vivo Neutron Activation Analysis (IVNAA) to detect manganese, aluminum, and other potentially toxic elements in human hand bone has been designed and its dosimetric specifications measured. The neutron source is a customized deuterium-deuterium neutron generator which produces neutrons at 2.45 MeV by the fusion reaction 2H(d, n)3He at a calculated flux of 7 x 108 +/-30% s-1. A moderator/reflector/shielding (5 cm high density polyethylene (HDPE), 5.3 cm graphite & 5.7 cm borated HDPE) assembly has been designed and built to maximize the thermal neutron flux inside the hand irradiation cavity and to reduce the extremity dose and effective dose to the human subject. Lead sheets are used to attenuate bremsstrahlung x rays and activation gammas. A Monte Carlo simulation (MCNP6) was used to model the system and calculate extremity dose. The extremity dose was measured with neutron and photon sensitive film badges and Fuji electronic pocket dosimeter (EPD). The neutron ambient dose outside the shielding was measured by Fuji NSN3, and photon dose by a Bicron MicroREM scintillator. Neutron extremity dose was calculated to be 32.3 mSv using MCNP6 simulations given a 10 min IVNAA measurement of manganese. Measurements by EPD and film badge indicate hand dose to be 31.7 +/- 0.8 mSv for neutron and 4.2 +/- 0.2 mSv for photon for 10 mins; whole body effective dose was calculated conservatively to be 0.052 mSv. Experimental values closely match values obtained from MCNP6 simulations. These are acceptable doses to apply the technology for a manganese toxicity study in a human population.

  20. Local variances in biomonitoring

    International Nuclear Information System (INIS)

    The present study deals with the (larger-scaled) biomonitoring survey and specifically focuses on the sampling site. In most surveys, the sampling site is simply selected or defined as a spot of (geographical) dimensions which is small relative to the dimensions of the total survey area. Implicitly it is assumed that the sampling site is essentially homogeneous with respect to the investigated variation in survey parameters. As such, the sampling site is mostly regarded as 'the basic unit' of the survey. As a logical consequence, the local (sampling site) variance should also be seen as a basic and important characteristic of the survey. During the study, work is carried out to gain more knowledge of the local variance. Multiple sampling is carried out at a specific site (tree bark, mosses, soils), multi-elemental analyses are carried out by NAA, and local variances are investigated by conventional statistics, factor analytical techniques, and bootstrapping. Consequences of the outcomes are discussed in the context of sampling, sample handling and survey quality. (author)

  1. Triton burnup measurements by neutron activation at JT-60U

    International Nuclear Information System (INIS)

    This paper describes measurements on triton burnup in a deuterium plasma by the detection of the 2.5 MeV neutrons (from DD fusion) and the 14 MeV neutrons (from DT fusion). The 2.5 MeV neutrons have been measured by fission chambers and activation of indium foils while the 14 MeV neutrons have been detected by activation of silicon, aluminum, and copper foils. The measured yields of the 2.5 MeV neutrons utilizing In foils are similar 20-40% higher than the yields obtained from fission chambers depending on what calibration factors are used. The deviation decreases with the plasma major radius (or increasing plasma volume). When the triton burnup is measured by utilizing neutron threshold reactions (En>2.5 MeV) and In foils, then systematic errors in the calibration factors cancel and the maximum deviation between the measured triton burnup for different calibration factors is reduced to similar 5%. The measurements indicate that triton burnup increases with the 14 MeV neutron yield, indicating that the relative yield of 14 MeV neutrons increases depending on the time duration of the deuterium neutral beam injection (NBI). Furthermore, the triton burnup decreases with an increased plasma major radius, indicating increased triton ripple losses, and increases with plasma current, indicating reduced banana orbit losses. (orig.)

  2. Internationally harmonised approach to biomonitoring trace element atmospheric deposition

    International Nuclear Information System (INIS)

    The International Atomic Energy Agency (IAEA) has been supporting work on airborne particulate matter since 1992 through various co-ordinated research and technical co-operation projects. In 1997, biomonitoring air pollution using plants, became officially a part of the IAEA project on environmental pollution monitoring and research. Based on: (1) positive experience in using biomonitors, especially lower plants such as mosses and lichens in several developed countries; (2) the continuous use of biomonitors in several Member States; and (3) the fact that nuclear and related analytical techniques have been shown to be particularly appropriate for the analysis of air pollution biomonitors, such studies are now being supported by the IAEA in 14 countries within a co-ordinated research project. The main emphasis of this project is on (1) identification of suitable biomonitors of atmospheric pollution for local and/or regional application, and (2) their validation for general environmental monitoring, whenever possible. Although the participants are using different plants as biomonitors in their research in geographically and climatically diverse parts of the world, they are harmonising sampling approaches and analytical procedures. In this paper, an overview of these activities is given, along with the details, where possible. In all of these activities, proficiency testing and analytical quality assurance are important issue, which merits special attention. To this end, a variety of analytical quality control materials have been used in intercomparison exercises and proficiency testing. Within the scope of the NAT-5 intercomparison exercise, two lichen materials were distributed among 15 participating laboratories and a proficiency test was organised. The results obtained proved satisfactory performance for most participating laboratories. (author)

  3. Neutron activation analysis of polyethylene from neutron shield of EDELWEISS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Rakhimov, Alimardon V. [Joint Institute for Nuclear Research (JINR), Dubna (Russian Federation); Uzbek Academy of Sciences (INP AS RUz), Tashkent (Uzbekistan). Inst. of Nuclear Physics; Brudanin, Viktor B.; Filosofov, Dmitry V. [Joint Institute for Nuclear Research (JINR), Dubna (Russian Federation); and others

    2015-07-01

    Instrumental neutron-activation analysis (INAA) was applied to estimate trace contaminations in polyethylene (PE) used as a neutron shield for low background setup of the EDELWEISS Dark Matter search experiment. PE samples with masses of 1-10 grams each were irradiated at the WWR-SM nuclear reactor by neutron flux of 1 x 10{sup 14}n/(cm{sup 2}s) for 5-48 h. The radioactivity was measured by high-resolution γ-ray spectrometry. In PE samples of two types, more than 30 trace elements were determined at a concentration level of 10{sup -5} to 10{sup -11} g/g.

  4. Simultaneous speciation analysis using neutron activation

    International Nuclear Information System (INIS)

    Full text: Neutron activation analysis (NAA) is a well-established analytical technique for the simultaneous determination of multielement concentrations. Although various forms of NAA have been traditionally applied to measuring the total concentrations of elements, the scope of NAA can be further extended in conjunction with pre-irradiation chemical separations to determine the species of an element. The technique can then be called speciation NAA (SNAA). Since much of the toxicity of an element depends on its physico-chemical forms, there is an increasing interest in studying its speciation. A number of characteristic features of NAA, which other techniques normally do not possess, can be advantageously exploited in SNAA. For example, SNAA has simultaneous multielement specificity unlike AAS and AFS. The SNAA technique can be applied to the simultaneous speciation of elements which are not chemically similar such as Cd, Se and I, as well as to the elements such as Cl, Br and I which are rather difficult to determine by most other techniques. Qualitative as well as quantitative analysis of small samples can be done by SNAA with excellent precision, accuracy, sensitivity, and rapidity. Unlike many other techniques, SNAA has some enhanced quality assurance capabilities. We have developed SNAA methods for separating various inorganic and organic arsenic species in water and in sea foods. We are presently extending these methods to include simultaneous speciation of As, Sb and Se. We have also developed SNAA methods employing biochemical techniques for the characterization of metalloproteins and protein-bound trace element species of Se along with Cd, Cu, Mn, Mo and Zn in bovine kidneys. Lately, we have concentrated our efforts to develop SNAA methods in conjunction with HPLC, RPC, SEC, NMR and MS for the simultaneous separation and characterization of extractable organo chlorine, organo bromine and organo iodine species in fisheries samples. An overview of the

  5. Diagnosis of mucoviscidosis by neutron activation analysis. Part 1

    International Nuclear Information System (INIS)

    Symptoms pathology, incidence, and gravity of the inherent syndrome called mucoviscidosis, or cystic fibrosis are described in this Part I. The analytical methods used for its diagnosis, both the conventional chemical ones and by neutron activation analysis are also summarised. Finally, an analytical method to study the incidence of mucoviscidosis in Brazil is presented. This , essentially, consists in bromine determination, in fingernails, by resonance neutron activation analysis. (author)

  6. Factors affecting 210Po and 210Pb activity concentrations in mussels and implications for environmental bio-monitoring programmes

    International Nuclear Information System (INIS)

    The activity of 210Po and 210Pb was determined in mussels of the same size (3.5-4.0 cm shell length) sampled monthly over a 17-month period at the Atlantic coast of Portugal. Average radionuclide concentration values in mussels were 759 ± 277 Bq kg-1 for 210Po (range 460-1470 Bq kg-1 dry weight), and 45 ± 19 Bq kg-1 for 210Pb (range 23-96 Bq kg-1 dry weight). Environmental parameters and mussel biometric parameters were monitored during the same period. Although there was no seasonal variation of radionuclide concentrations in sea water during the study period, the concentration of radionuclide activity in mussels varied seasonally displaying peaks of high concentrations in winter and low concentrations in summer. Analysis of radionuclide data in relation to the physiological Condition Index of mussels revealed that 210Po and 210Pb activities in the mussel (average activity per individual) remained nearly constant during the investigation period, while mussel body weight fluctuated due to fat storage/expenditure in the soft tissues. Similar variation of radionuclide concentrations was observed in mussels transplanted from the sea coast into the Tejo Estuary. However, under estuarine environmental conditions and with higher food availability throughout the year, transplanted mussel Condition Index was higher than in coastal mussels and average radionuclide concentrations were 210 ± 75 Bq kg-1 (dry weight) for 210Po and 10 ± 4 Bq kg-1 (dry weight) for 210Pb, therefore lower than in coastal mussels with similar shell length. It is concluded that the apparent seasonal fluctuation and inter-site difference of radionuclide concentrations were mostly caused by mussel body weight fluctuation and not by radionuclide body burden fluctuation. This interpretation can be extended to the apparent seasonal fluctuation in concentrations of lipophilic and lipophobic contaminants in mussels, and provides an explanation for occasional high concentrations of 210Po and man

  7. Air Pollution Studies in Central Russia (Tula Region) Using Moss Biomonitoring Technique, NAA and AAS

    CERN Document Server

    Ermakova, E V; Steinnes, E

    2002-01-01

    For the first time the moss biomonitoring technique has been applied to air pollution monitoring in Central Russia (Tula Region). Moss samples were collected from 83 sites in accordance with the sampling strategy of European projects on biomonitoring of atmospheric deposition. Neutron activation analysis (NAA) at the IBR-2 reactor has made it possible to determine the concentration of 33 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, As, Br, Rb, Sr, Mo, Sb, I, Cs, Ba, La, Ce, Sm, Tb, Yb, Hf, Ta, W, Th, U) over a large concentration range (from 10000 mg/kg for K to 0.001 mg/kg for Tb and Ta). In addition to NAA, flame AAS (atomic absorption spectrometry) was applied to determine the concentration of Cd, Cu and Pb. Factor analysis was applied to determine possible sources of elements detected in the investigated mosses. Eight factors were identified. The geographical distribution of factor scores is presented. The interpretation of the factor analysis findings points to natural as well as anthr...

  8. Heavy Metals and Trace Elements Atmospheric Deposition Studies in Tula Region Using Moss Biomonitors Technique

    CERN Document Server

    Ermakova, E V; Steinnes, E

    2002-01-01

    For the first time the moss biomonitors technique was used in air pollution studies in Tula Region (Central Russia), applying NAA, AAS. Moss samples were collected at 83 sites in accordance with the sampling strategy adopted in European projects on biomonitoring atmospheric deposition. A wide set of trace elements in mosses was determined. The method of epithermal neutron activation at IBR-2 reactor of FLNP JINR has made it possible to identify 33 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, As, Br, Rb, Sr, Mo, Sb, I, Cs, Ba, La, Ce, Sm, Tb, Yb, Hf, Ta, W, Th, U) in the large-scale concentration range - from 10000 ppm for K to 0,001 ppm for Tb and Ta. Cu, Cd and Pb were determined by the flame AAS in the Norwegian Institute of Science and Technology. Using the graphical technique and principal component analysis allowed to separate plant, crustal and general pollution components in the moss. The obtained data will be used for constructing coloured maps of the distribution of elements over t...

  9. Air Pollution Studies in Central Russia (Tver and Yaroslavl Regions) Using the Moss Biomonitoring Technique and Neutron Activation Analysis

    CERN Document Server

    Ermakova, E V; Pavlov, S S; Povtoreiko, E A; Steinnes, E; Cheremisina, Ye N

    2003-01-01

    Data of 34 elements, including heavy metals, halogens, rare-earth elements, U, and Th in 140 moss samples, collected in central Russia (Tver and Yaroslavl regions and the northern part of Moscow Region) in 2000-2002, are presented. Factor analysis with VARIMAX rotation was applied to identify possible sources of the elements determined in the mosses. The seven resulting factors represent crust, vegetation and anthropogenic components in the moss. Some of the factors were interpreted as being associated with ferrous smelters (Fe, Zn, Sb, Ta); combination of non-ferrous smelters and other industries (Mn, Co, Mo, Cr, Ni, W); an oil-refining plant, and oil combustion at the thermal power plant (V, Ni). The geographical distribution patterns of the factor scores are also presented. The dependency equations of elemental content in mosses versus distance from the source are derived.

  10. Application of inelastic neutron scattering and prompt neutron activation analysis in coal quality assessment

    International Nuclear Information System (INIS)

    The basic principles are assessed of the determination of ash content in coal based on the measurement of values proportional to the effective proton number. Discussed is the principle of coal quality assessment using the method of inelastic neutron scattering and prompt neutron activation analysis. This is done with respect both to theoretical relations between measured values and coal quality attributes and to practical laboratory measurements of coal sample quality by the said methods. (author)

  11. The instrumental neutron activation determination of impurities in technical cobalt

    International Nuclear Information System (INIS)

    Instrumental neutron activation techniques for determination of 13 impurities with detection limit 10-5 - 10-2% in technical cobalt have been developed by using thermal and epithermal neutrons of nuclear reactor. Self-shielding and disturbance of neutron flux(Co59 has high capture cross-section of neutrons) by sample were taken into account by using some references and from the results obtained in preliminary experiments. Samples and standards have been placed in such a way that neutron flux disturbance was less than 2-3%. The Al-Pb-Cd-Cu filter was used for absorption of low energy γ-rays of Co60m and Co61. (author)

  12. Determination of total Betta-activity and heavy metals in biomonitor species (phytomonitors) from the area of ITR-Sofia

    International Nuclear Information System (INIS)

    For the purposes of environmental assessment of the area around the Research reactor in Sofia, species from monitored control points, selected in a certain way (habitat, population, air and hydrogeological parameters) are examined. Samples from following phytomonitored species: Betula pendula (silver birch) popullus canadensis (Canadian populus), Quercus sp. (Oak), Dactilus glomerata (Cock's-foot), Abies alba (Silver Fir) and Sequoia sempervirens (Coast Redwood) were analyzed. The total beta activity was determined by radiometric analysis and heavy metals content was measured using X-ray fluorescence analysis. The results are discussed in terms of radiation monitoring program of INRNE (gamma-background, aerosols, surface and groundwater, soil, plants) and obtained values are compared with reference points in the country

  13. In vivo neutron activation facility at Brookhaven National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Ma, R.; Yasumura, Seiichi; Dilmanian, F.A.

    1997-11-01

    Seven important body elements, C, N, Ca, P, K, Na, and Cl, can be measured with great precision and accuracy in the in vivo neutron activation facilities at Brookhaven National Laboratory. The facilities include the delayed-gamma neutron activation, the prompt-gamma neutron activation, and the inelastic neutron scattering systems. In conjunction with measurements of total body water by the tritiated-water dilution method several body compartments can be defined from the contents of these elements, also with high precision. In particular, body fat mass is derived from total body carbon together with total body calcium and nitrogen; body protein mass is derived from total body nitrogen; extracellular fluid volume is derived from total body sodium and chlorine; lean body mass and body cell mass are derived from total body potassium; and, skeletal mass is derived from total body calcium. Thus, we suggest that neutron activation analysis may be valuable for calibrating some of the instruments routinely used in clinical studies of body composition. The instruments that would benefit from absolute calibration against neutron activation analysis are bioelectric impedance analysis, infrared interactance, transmission ultrasound, and dual energy x-ray/photon absorptiometry.

  14. Studies on application of neutron activation analysis -Applied research on air pollution monitoring and development of analytical method of environmental samples

    International Nuclear Information System (INIS)

    This research report is written for results of applied research on air pollution monitoring using instrumental neutron activation analysis. For identification and standardization of analytical method, 24 environmental samples are analyzed quantitatively, and accuracy and precision of this method are measured. Using airborne particulate matter and biomonitor chosen as environmental indicators, trace elemental concentrations of sample collected at urban and rural site monthly are determined ant then the calculation of statistics and the factor analysis are carried out for investigation of emission source. Facilities for NAA are installed in a new HANARO reactor, functional test is performed for routine operation. In addition, unified software code for NAA is developed to improve accuracy, precision and abilities of analytical processes. (author). 103 refs., 61 tabs., 19 figs

  15. Raw materials for low-activation concrete neutron shields

    International Nuclear Information System (INIS)

    Concrete surrounding a nuclear accumulates radioisotopes induced by neutron reactions during operation, and this concrete still remains to an enormous degree as radioactive waste after decommissioning. The disposal of such activated concrete is very costly and requires strict supervision. Hence, there has been a strong desire to develop a concrete that retains little residual radioactivity, that is, ''low-activation'' concrete. In the present study, we have identified several raw materials for such concrete - low-activation limestone, quartzite, colemanite, alumina-ceramics, while Portland cement and high-alumina cement - by performing a screening test for neutron irradiation. The results show that low-activation concrete compounded from such low-activation raw materials should serve for neutron shielding. Another noteworthy finding is that limestone occurring near schalstein deposits, and especially when sandwiched between two beds of schalstein, is an excellent low-activation raw material. (author)

  16. Elemental analysis of brazing alloy samples by neutron activation technique

    International Nuclear Information System (INIS)

    Two brazing alloy samples (C P2 and C P3) have been investigated by Neutron activation analysis (NAA) technique in order to identify and estimate their constituent elements. The pneumatic irradiation rabbit system (PIRS), installed at the first egyptian research reactor (ETRR-1) was used for short-time irradiation (30 s) with a thermal neutron flux of 1.6 x 1011 n/cm2/s in the reactor reflector, where the thermal to epithermal neutron flux ratio is 106. Long-time irradiation (48 hours) was performed at reactor core periphery with thermal neutron flux of 3.34 x 1012 n/cm2/s, and thermal to epithermal neutron flux ratio of 79. Activation by epithermal neutrons was taken into account for the (1/v) and resonance neutron absorption in both methods. A hyper pure germanium detection system was used for gamma-ray acquisitions. The concentration values of Al, Cr, Fe, Co, Cu, Zn, Se, Ag and Sb were estimated as percentages of the sample weight and compared with reported values. 1 tab

  17. Beryllium neutron activation detector for pulsed DD fusion sources

    International Nuclear Information System (INIS)

    A compact fast neutron detector based on beryllium activation has been developed to perform accurate neutron fluence measurements on pulsed DD fusion sources. It is especially well suited to moderate repetition-rate (9Be(n,α)6He cross-section, energy calibration of the proportional counters, and numerical simulations of neutron interactions and beta-particle paths using MCNP5. The response function R(En) is determined over the neutron energy range 2-4 MeV. The count rate capability of the detector has been studied and the corrections required for high neutron fluence measurements are discussed. For pulsed DD neutron fluencies >3×104 cm-2, the statistical uncertainty in the fluence measurement is better than 1%. A small plasma focus device has been employed as a pulsed neutron source to test two of these new detectors, and their responses are found to be practically identical. Also the level of interfering activation is found to be sufficiently low as to be negligible.

  18. Absolute technique for neutron source calibration by radiation induced activity

    International Nuclear Information System (INIS)

    The neutron yield from a Radium Beryllium neutron source has been determined experimentally by the induced Mn-56 activity. The neutron source was placed in the center of a tank filled with aqueous manganese sulphate (MnSO4) solution. Irradiation time usually lasted about 16-18 hours in order to secure saturation. The average induced Mn-56 activity within the MnSO4 bath was then measured by the use of NaI scintillation detector. This detector was placed in a sealed aluminum jacket at the center of the tank. This detector was connected with the necessary electronic counting system and was pre calibrated against a 4 πβ-γ coincidence counting system. The efficiency of the NaI counting system as a function of MnSO4 solution density is investigated as well as the proper dimension of the used tank for the sake of calibration purposes. The neutron leakage within the MnSO4 baths was also investigated for different dimensions of tanks. The experimental errors involved in the counting system were also considered. The numerical value of neutron yield from the used radium beryllium neutron source was given with its corresponding statistical errors as (1.10 + 0.065) x 106 neutron per second

  19. Active biomonitoring with Corbicula for USEPA priority pollutant and metal sources in the Anacostia River (DC, Maryland, USA).

    Science.gov (United States)

    Phelps, Harriette L

    2016-07-01

    The freshwater Anacostia River watershed (Maryland, DC, USA) was surveyed for the sources of bioavailable US Environmental Protection Agency (USEPA) Priority Pollutants and toxic metals by active biomontoring (ABM) using the freshwater Asiatic clam Corbicula fluminea. The Anacostia River is a 456 km(2) tributary of the tidal freshwater Potomac River that includes the city of Washington, DC where edible fish are highly contaminated with PCBs and chlordane. From 1999 to 2011, Corbicula were collected for ABM from a Potomac reference site and translocated in cages placed at 45 sites in the tidal and nontidal Anacostia watershed. Minimum clam mortality and maximum contaminant bioaccumulation was with 2-week translocation. The clam tissues (28-50) were combined at sites and analyzed by TestAmerica for 66 USEPA Priority Pollutants plus technical chlordane, benz(e) pyrene, and 6 metals (As, Cd, Cr, Cu, Fe, Pb). Tissue contaminants reflected water, not sediment, levels. To compare sites, all contaminant data above detection or reference were grouped as total metals (TMET), total polycyclic aromatic hydrocarbons (TPAH), total PCB congeners (TPCB), total pesticides (TPEST), and total technical chlordane (TCHL). Tidal Anacostia ABM found highest TPAH and TCHL upstream at Bladensburg Marina (MD) except for TCHL at site PP near the confluence. Five nontidal MD subtributaries (94% of flow) had 17 sites with bioavailable TPAH, TPCB, or TCHL 2 to 3 times higher than found at the toxic-sediment "hotspots" near Washington. The only TMET noted was Fe at 1 site. TPAH in MD subtributaries was highest near industrial parks and Metro stations. A naphthalene spill was detected in Watts Branch. TPCB (low molecular weight) originated upstream at 1 industrial park. Total technical chlordane (80% of TPEST) was 2 to 5 times the US Food and Drug Administration action in 4 nontidal tributaries where heptachlor indicated legacy chlordane dumpsites. Total technical chlordane fell to reference

  20. Neutron activation analysis of wheat samples

    Energy Technology Data Exchange (ETDEWEB)

    Galinha, C. [CERENA-IST, Technical University of Lisbon, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal); Instituto Tecnoclogico e Nuclear, URSN, E.N. 10, 2686-953 Sacavem (Portugal); Anawar, H.M. [Instituto Tecnoclogico e Nuclear, URSN, E.N. 10, 2686-953 Sacavem (Portugal); Freitas, M.C., E-mail: cfreitas@itn.pt [Instituto Tecnoclogico e Nuclear, URSN, E.N. 10, 2686-953 Sacavem (Portugal); Pacheco, A.M.G. [CERENA-IST, Technical University of Lisbon, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal); Almeida-Silva, M. [Instituto Tecnoclogico e Nuclear, URSN, E.N. 10, 2686-953 Sacavem (Portugal); Coutinho, J.; Macas, B.; Almeida, A.S. [INRB/INIA-Elvas, National Institute of Biological Resources, Est. Gil Vaz, 7350-228 Elvas (Portugal)

    2011-11-15

    The deficiency of essential micronutrients and excess of toxic metals in cereals, an important food items for human nutrition, can cause public health risk. Therefore, before their consumption and adoption of soil supplementation, concentrations of essential micronutrients and metals in cereals should be monitored. This study collected soil and two varieties of wheat samples-Triticum aestivum L. (Jordao/bread wheat), and Triticum durum L. (Marialva/durum wheat) from Elvas area, Portugal and analyzed concentrations of As, Cr, Co, Fe, K, Na, Rb and Zn using Instrumental Neutron Activation Analysis (INAA) to focus on the risk of adverse public health issues. The low variability and moderate concentrations of metals in soils indicated a lower significant effect of environmental input on metal concentrations in agricultural soils. The Cr and Fe concentrations in soils that ranged from 93-117 and 26,400-31,300 mg/kg, respectively, were relatively high, but Zn concentration was very low (below detection limit <22 mg/kg) indicating that soils should be supplemented with Zn during cultivation. The concentrations of metals in roots and straw of both varieties of wheat decreased in the order of K>Fe>Na>Zn>Cr>Rb>As>Co. Concentrations of As, Co and Cr in root, straw and spike of both varieties were higher than the permissible limits with exception of a few samples. The concentrations of Zn in root, straw and spike were relatively low (4-30 mg/kg) indicating the deficiency of an essential micronutrient Zn in wheat cultivated in Portugal. The elemental transfer from soil to plant decreases with increasing growth of the plant. The concentrations of various metals in different parts of wheat followed the order: Root>Straw>Spike. A few root, straw and spike samples showed enrichment of metals, but the majority of the samples showed no enrichment. Potassium is enriched in all samples of root, straw and spike for both varieties of wheat. Relatively to the seed used for cultivation

  1. Neutron activation analysis of wheat samples

    International Nuclear Information System (INIS)

    The deficiency of essential micronutrients and excess of toxic metals in cereals, an important food items for human nutrition, can cause public health risk. Therefore, before their consumption and adoption of soil supplementation, concentrations of essential micronutrients and metals in cereals should be monitored. This study collected soil and two varieties of wheat samples-Triticum aestivum L. (Jordao/bread wheat), and Triticum durum L. (Marialva/durum wheat) from Elvas area, Portugal and analyzed concentrations of As, Cr, Co, Fe, K, Na, Rb and Zn using Instrumental Neutron Activation Analysis (INAA) to focus on the risk of adverse public health issues. The low variability and moderate concentrations of metals in soils indicated a lower significant effect of environmental input on metal concentrations in agricultural soils. The Cr and Fe concentrations in soils that ranged from 93-117 and 26,400-31,300 mg/kg, respectively, were relatively high, but Zn concentration was very low (below detection limit Fe>Na>Zn>Cr>Rb>As>Co. Concentrations of As, Co and Cr in root, straw and spike of both varieties were higher than the permissible limits with exception of a few samples. The concentrations of Zn in root, straw and spike were relatively low (4-30 mg/kg) indicating the deficiency of an essential micronutrient Zn in wheat cultivated in Portugal. The elemental transfer from soil to plant decreases with increasing growth of the plant. The concentrations of various metals in different parts of wheat followed the order: Root>Straw>Spike. A few root, straw and spike samples showed enrichment of metals, but the majority of the samples showed no enrichment. Potassium is enriched in all samples of root, straw and spike for both varieties of wheat. Relatively to the seed used for cultivation, Jordao presented higher transfer coefficients than Marialva, in particular for Co, Fe, and Na. The Jordao and Marialva cultivars accumulated not statistically significant different

  2. Air pollution studies in Macedonia using the moss biomonitoring technique, NAA, AAS and GIS technology

    International Nuclear Information System (INIS)

    For the first time the moss biomonitoring technique was applied to air pollution studies in the Republic of Macedonia, in the central part of the Balkan Peninsula. Samples of the terrestrial mosses Hypnum cupressiforme, Campothecium lutescens, and Homolothecium sericium were collected in September-October 2002 in accordance with the sampling strategy of the European moss survey programme. The sampling network included 73 sites evenly distributed over the territory of the country. A total of 43 elements (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Ag, Cd, In, Sb, I, Cs, Ba, La, Ce, Sm, Eu, Tb, Hf, Ta, W, Au, Hg, Pb, Th, and U) were determined by instrumental epithermal neutron activation analysis and flame

  3. Analysis of the toenail as a biomonitor of supranutritional intake of Zn, Cu, and Mg

    International Nuclear Information System (INIS)

    The toenail was examined as a biological monitor of Mg, Zn, and Cu intake using an observational case control model. The One Source Cohort matched 63 individuals in Columbia Missouri who took the One Source multivitamin with 63 control individuals. The matching criteria were based on age, sex, ethnicity, smoking status, and body mass index. The multivitamin contained supra-nutritional levels of Se, Mg, Cu, and Zn. The toenail clippings were examined for these elements using instrumental neutron activation analysis (INAA). A statistical analysis did not indicate a significant difference for Mg, Cu, or Zn between the nails of One Source supplement users and control subjects (p-4). This internal Se control suggests that the One Source Cohort is largely free from misclassification errors that could interfere with the biomonitor response for the supranutritional intake of Mg, Cu, and Zn. (author)

  4. Research and development activities of a neutron generator facility

    International Nuclear Information System (INIS)

    The neutron generator facility at YNRC is used for elemental analysis, nuclear data measurement and education. In nuclear data measurement the focus is on re-evaluating the existing scattered nuclear activation cross-section to obtain systematic data for nuclear reactions such as (n,p), (n,α), and (n,2n). In elemental analysis it is used for analyzing the Nitrogen (N), Phosphor (P) and Potassium (K) contents in chemical and natural fertilizers (compost), protein in rice, soybean, and corn and pollution level in rivers. The neutron generator is also used for education and training of BATAN staff and university students. The facility can also produce neutron generator components. (author)

  5. Determination of trace elements in lichen samples by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Samples of Canoparmelia texana lichen collected in different sites of Sao Paulo and Parana States, Brazil, were analysed by neutron activation analysis in order to obtain preliminary information on the air quality in these regions and also to select a region of interest for biomonitoring studies. Also Tadescantia pallida plant has been analysed in order to study the viability of using this specimen in environmental pollution monitoring. Lichens samples were collected from tree barks which were also collected to investigate the contribution of substrate derived elements to elements present in lichens. Young and old leaves of T. pallida were collected separately in order to study the leaf age effects on their elemental levels. The samples were cleaned, washed with distilled water, dried and ground for the analyses. Samples and standards were irradiated at the IEA-Rlm nuclear reactor for short and long periods and concentrations of the elements Al, As, Ca, Cd, Cl, Co, Cr, Cs, Fe, Hf, Mg, Mn, Rb, Sb, Sc, D, Th, U, V Zn and lanthanides were determined. Preliminary results obtained for T. texana lichen indicated that three sites (Ibiuna, Botanical Garden and Parque de Vila Velha) present low concentrations of the most elements analysed. Therefore lichens from these regions could be analysed to establish baseline levels of elements for monitoring purposes. Samples collected in open areas presented high concentrations of some elements probably due to the accumulation of elements originating from soil and from heavy vehicular traffic. Elemental concentrations obtained in outer barks were similar or smaller than those results obtained for lichens. Results obtained for T. pallida indicated that concentrations of elements in old leaves of this plant are of the same magnitude or slightly higher than those presented in young ones. (author)

  6. Background by neutron activation in GERDA

    International Nuclear Information System (INIS)

    The observation of the neutrinoless double beta decay is a proof of the Majorana nature of the neutrino. The long half-life of this decay requires experiments of very low background rates in the region of interest at Qββ. Prompt γ-rays after neutron capture on germanium and the β-decay of 77Ge contribute to the background in experiments using 76Ge for the search of the neutrinoless double beta decay. The poorly known prompt γ-ray spectra and the neutron capture cross sections for the (n,γ) reactions of 74Ge and 76Ge were measured at the research reactor FRM II (Munich). The obtained data are needed in MC simulations for qualitative and quantitative background prediction in the Gerda experiment. The data and their implication on the background in Gerda are presented.

  7. Interpretation of active neutron measurements by the heterogeneous theory

    International Nuclear Information System (INIS)

    In this paper are presented results from a study on the application of the heterogeneous method for the interpretation of active neutron measurements. The considered apparatus consists out of a cylindrical lead pile, which is provided with two axial channels: a central channel incorporates an antimony beryllium photoneutron source and an excentric channel serves for the insertion of the sample to be assayed for fissionable materials contents. The mathematical model of this apparatus is the heterogeneous group diffusion theory. Sample and source channel are described by multigroup monopolar and dipolar sources and sinks. Monopolar sources take account of neutron production within energy group and in-scatter from upper groups. Monopolar sinks represent neutron removal by absorption within energy group and outscatter to lower groups. Dipol sources describe radial streaming of neutrons across the sample channel. Multigroup diffusion theory is applied throughout the lead pile. The strengths of the monopolar and dipolar sources and sinks are determined by linear extrapolation distances of azimuthal mean and first harmonic flux values at the channels' surface. In an experiment we may measure the neutrons leaking out of the lead pile and linear extrapolation distances at the channels' surface. Such informations are utilized for interpretation in terms of fission neutron source strengh and mean neutron flux values in the sample. In this paper we summarized the theoretical work in course

  8. Evaluation of new pharmaceuticals using in vivo neutron inelastic scattering and neutron activation analysis

    International Nuclear Information System (INIS)

    Nutritional status of patients can be evaluated by monitoring changes in body composition, including depletion of protein and muscle, adipose tissue distribution and changes in hydration status, bone or cell mass. Fast neutron activation (for N and P) and neutron inelastic scattering (for C and O) are used to assess in vivo elements characteristic of specific body compartments. The fast neutrons are produced with a sealed deuterium-tritium (D-T) neutron generator. This method provides the most direct assessment of body composition. Non-bone phosphorus for muscle is measured by the 31P(n,α)28Al reaction, and nitrogen for protein via the (n,2n) fast neutron reaction. Inelastic neutron scattering is used for the measurement of total body carbon and oxygen. Carbon is used to derive body fat, after subtracting carbon contributions due to protein, bone and glycogen. Carbon-to-oxygen (C/O) ratio is used to measure distribution of fat and lean tissue in the body and to monitor small changes of lean mass and its quality. In addition to evaluating the efficacy of new treatments, the system is used to study the mechanisms of lean tissue depletion with aging and to investigate methods for preserving function and quality of life in the elderly. (author)

  9. The comparison of four neutron sources for Prompt Gamma Neutron Activation Analysis (PGNAA) in vivo detections of boron

    OpenAIRE

    Fantidis, J. G.; Nicolaou, G. E.; C. Potolias; N. Vordos; Bandekas, D. V.

    2011-01-01

    A Prompt Gamma Ray Neutron Activation Analysis (PGNAA) system, incorporating an isotopic neutron source has been simulated using the MCNPX Monte Carlo code. In order to improve the signal to noise ratio different collimators and a filter were placed between the neutron source and the object. The effect of the positioning of the neutron beam and the detector relative to the object has been studied. In this work the optimisation procedure is demonstrated for boron. Monte Carlo calculations were...

  10. Cadmium filtered neutron flux determination. Comparison of activation methods

    International Nuclear Information System (INIS)

    Neutron fluxes under cadmium filters are determined by the cadmium ratio and sandwich activation methods. The thermal neutron flux levels obtained with 7 detectors of different kinds: In, Au, Ag, W, Co, Mn, Zn are compared. The cadmium ratio method was used in locations for which the epithermal and thermal neutron flux ratio are quite different. By irradiating materials under different thicknesses of cadmium it was possible to establish experimental curves from which the flux depression factors for intermediate neutrons may be determined whatever the thickness of the filter used. Whereas the cadmium ratio method can only measure the mean flux above the cadmium cut-off energy the sandwich method enables the flux value to be determined in a narrow band around the resonance energy of each detector used

  11. NaI detector neutron activation spectra for PGNAA applications

    Science.gov (United States)

    Gardner; El; Zheng; Hayden; Mayo

    2000-10-01

    When NaI detectors are used in prompt gamma-ray neutron activation analysis devices, they are activated by neutrons that penetrate the detector. While thermal neutron filters like boron or lithium can be used to reduce this activation, it can never be completely eliminated by this approach since high energy neutrons can penetrate the detector and thermalize inside it. This activation results in the emission of prompt gamma rays from both the I and Na and the production of the radioisotopes 128I and 24Na that subsequently decay and emit their characteristic beta particles and gamma rays. The resulting three spectra represent a background for this measurement. An experimental method for obtaining these three spectra is described and results are reported for 2" x 2", 5" x 5", 6" x 6", and 1" x 6" NaI detectors using the thermal neutron beam of the NCSU PULSTAR nuclear reactor. In addition, Monte Carlo simulation programs have been developed and used for simulating these spectra. Good results have been obtained by the Monte Carlo method for the two radioisotope spectra, and it is anticipated that good results will also be obtained for the prompt gamma-ray spectrum when the I and Na coincidence schemes are known. PMID:11003483

  12. NaI detector neutron activation spectra for PGNAA applications

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, R.P. E-mail: gardner@ncsu.edu; Sayyed, El; Zheng Yuanshui; Hayden, Stephanie; Mayo, C.W

    2000-11-15

    When NaI detectors are used in prompt gamma-ray neutron activation analysis devices, they are activated by neutrons that penetrate the detector. While thermal neutron filters like boron or lithium can be used to reduce this activation, it can never be completely eliminated by this approach since high energy neutrons can penetrate the detector and thermalize inside it. This activation results in the emission of prompt gamma rays from both the I and Na and the production of the radioisotopes {sup 128}I and {sup 24}Na that subsequently decay and emit their characteristic beta particles and gamma rays. The resulting three spectra represent a background for this measurement. An experimental method for obtaining these three spectra is described and results are reported for 2x2, 5x5, 6x6, and 1x6 NaI detectors using the thermal neutron beam of the NCSU PULSTAR nuclear reactor. In addition, Monte Carlo simulation programs have been developed and used for simulating these spectra. Good results have been obtained by the Monte Carlo method for the two radioisotope spectra, and it is anticipated that good results will also be obtained for the prompt gamma-ray spectrum when the I and Na coincidence schemes are known.

  13. Study on palladium determination by neutron activation analysis

    International Nuclear Information System (INIS)

    This study presents results of Pd determinations in neutron activation analysis of spiked biological tissues and CCQM-P63 automotive catalyst. Pd spiked biological tissues of bovine muscle and liver were prepared using a blender with titanium blades and Pd solutions. These materials obtained in a past form were freeze-dried and homogenized before the analysis. Thermal and epithermal neutron activation analyses were applied in these determinations. Separations of Pd from interfering elements were also carried out using solvent extraction and solid-phase extraction techniques, before the irradiations with epithermal neutrons. The irradiations were carried out at the IEA-R1 nuclear research reactor under thermal neutron flux of about 4 x 1012 n cm-2 s-1 during 4 and 16 h for thermal and epithermal irradiations, respectively. The gamma activities of 109Pd of the irradiated samples and Pd standard were measured using an HGe detector coupled to a gamma ray spectrometer. Results obtained in these analyses indicated that the epithermal irradiation presented higher sensitivity, due to the reduction of interferences. The pre-separation procedure of solid-phase extraction applied also yielded low detection limit. Comparisons made between the Pd results obtained using different procedures of neutron activation analysis indicated a good agreement. The analyses carried out in replicates also indicated a good precision with relative standard deviations varying from 1.2 to 14 %. (author)

  14. MA-1 unit for instrumental fast neutron activation analysis

    International Nuclear Information System (INIS)

    A description of the MA-1 facility intended for performing an instrumental multielement activation analysis is giveperation of facility is based on the spectrometry of samples activated with fast neutrons. The facility comprises the M-6000 control computer complex, the 10N fast neutron generator, the ARS-28G pneumatic transporter, spectrometric devices and detection units. The facility can be used to determine the contents of more than 50 elements in different combinations in compact and powdery substances. Maximum sensitivity is achieved when determining Pr, Cu, Br, Ba, Pb, Sb, Si, P, Al, O and F. The measuring equipment of the facility is universal and after proper modification can be used in activation analysis with the use of nuclear reactors, electron accelerators, a cyclotron and neutron sources

  15. Partial neutron capture cross sections of actinides using cold neutron prompt gamma activation analysis

    International Nuclear Information System (INIS)

    Nuclear waste needs to be characterized for its safe handling and storage. In particular long-lived actinides render the waste characterization challenging. The results described in this thesis demonstrate that Prompt Gamma Neutron Activation Analysis (PGAA) with cold neutrons is a reliable tool for the non-destructive analysis of actinides. Nuclear data required for an accurate identification and quantification of actinides was acquired. Therefore, a sample design suitable for accurate and precise measurements of prompt γ-ray energies and partial cross sections of long-lived actinides at existing PGAA facilities was presented. Using the developed sample design the fundamental prompt γ-ray data on 237Np, 241Am and 242Pu were measured. The data were validated by repetitive analysis of different samples at two individual irradiation and counting facilities - the BRR in Budapest and the FRM II in Garching near Munich. Employing cold neutrons, resonance neutron capture by low energetic resonances was avoided during the experiments. This is an improvement over older neutron activation based works at thermal reactor neutron energies. 152 prompt γ-rays of 237Np were identified, as well as 19 of 241Am, and 127 prompt γ-rays of 242Pu. In all cases, both high and lower energetic prompt γ-rays were identified. The most intense line of 237Np was observed at an energy of Eγ=182.82(10) keV associated with a partial capture cross section of σγ=22.06(39) b. The most intense prompt γ-ray lines of 241Am and of 242Pu were observed at Eγ=154.72(7) keV with σγ=72.80(252) b and Eγ=287.69(8) keV with σγ=7.07(12) b, respectively. The measurements described in this thesis provide the first reported quantifications on partial radiative capture cross sections for 237Np, 241Am and 242Pu measured simultaneously over the large energy range from 45 keV to 12 MeV. Detailed uncertainty assessments were performed and the validity of the given uncertainties was demonstrated. Compared

  16. Neutron Activation Experiments on Niobium in NPI p-(7)Li Quasi-monoenergetic Neutron Field

    Czech Academy of Sciences Publication Activity Database

    Honusek, Milan; Bém, Pavel; Burjan, Václav; Götz, Miloslav; Kroha, Václav; Novák, Jan; Šimečková, Eva; Fischer, U.; Simakov, SP.

    2011-01-01

    Roč. 59, č. 2 (2011), s. 1374-1377. ISSN 0374-4884 Institutional research plan: CEZ:AV0Z10480505 Keywords : ND2010 * Nuclear data * Neutron activation * EAF, ENDF, Nb Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.447, year: 2011

  17. Neutron activation analysis for environmental sample in Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Busamongkol, Arporn; Nouchpramool, Sunun; Bunprapob, Supamatthree [Office of Atomic Energy for Peace, Bangkok (Thailand); Sumitra, Tatchai [Chulalongkorn Univ., Dept. of Nuclear Technology, Bangkok (Thailand)

    2003-03-01

    Neutron Activation Analysis has been applied for the trace elements analysis in environmental samples. Thirty three samples of airborne particulate were collected every week at Ongkharak Nuclear Research Center (ONRC) during the period of June 1998 to March 1999. The Ti, I, Mg, Na, V, K, Cl, Al, Mn, Ca, As, Sm, Sb, Br, La, Ce, Th, Cr, Cs, Sc, Rb, Fe, Zn and Co were analyzed by Neutron Activation Analysis utilizing 2 MW TRIGA MARK III research reactor. The certified reference materials 1632a and 1633a from National Bureau of Standard were select as standard. (author)

  18. Neutron Activation Analysis for investigation of elemental composition of Amarantus

    International Nuclear Information System (INIS)

    In this work instrumental neutron activation analysis is applied for the characterization of the elemental composition of Amaranthus seeds, known in the prehistorical period, a tropical plant with promising nutritional and economic value. The characterization is enriched by the results of radiochemical neutron activation analysis for cobalt, molybdenum and uranium content. The comparison of the results, for three sorts of edible flour, commercially available: Soya Flour, Corn Bean Flour and Amaranthus Flour, is presented. The validation of the analytical methods used was carried out on the basis of participation in the interlaboratory comparison organized by the INCT (INCT-TL-1, INCT-MPH-2) and by NIST (SRM 1575a). (author)

  19. Neutron activation analysis of multielement in human organs

    International Nuclear Information System (INIS)

    To obtain the reference values or ranges of the elemental abundances in organs of Japanese male, neutron activation analysis was applied to nine kinds of autopsied organs, brain, heart, kidney, liver, lung, muscle, pancreas, spleen and thyroid. An applicability of multielement analysis of organs was studied prior to ordinary work. Accuracy and precision were investigated by analyzing the IAEA Certified Reference Materials, Horse Kidney, Whey Powder and Marine Sediment. The changes of count rate on various weights and the variations of the elemental abundances of five portions in organ were examined. It was found that organs were homogeneous for neutron activation analysis, except for kidney and lung. (author)

  20. Analysis of ayurvedic medicinal leaves by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Concentrations of 15 elements were determined in medicinally important ayurvedic medicinal leaves. Instrumental neutron activation analysis was employed for the determination of the elements viz. Na, K, Br, Sm, Cr, Zn, Th, Rb, Sr, Fe, La, Co, Ce, Cs and Eu. The samples were neutron irradiated at 100 kW TRIGA -Mainz nuclear reactor and the induced activities were measured by gamma ray spectrometry using an efficiency calibrated high resolution high purity germanium (HPGe) detector. The concentrations of these elements in the medicinal leaves and their medicinal importance are discussed. (author)

  1. Multielemental analysis of soils by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    The results of an instrumental neutron activation analysis of some elemental concentrations in different soil samples near the industrial areas at Tirupati, India, are reported. Altogether 14 elements, Sm, La, Cr, Co, Zn, Cs, Ce, Th, Rb, Na, K, Sr, Fe and Eu were determined. The samples were irradiated with neutrons at the 100 kW Triga - Mainz research reactor and the induced activities were measured by gamma-ray spectrometry using an efficiency calibrated high resolution high purity germanium (HPGe) detector in connection with a multichannel analyzer. The results are discussed. (author)

  2. Neutron activation analysis for environmental sample in Thailand

    International Nuclear Information System (INIS)

    Neutron Activation Analysis has been applied for the trace elements analysis in environmental samples. Thirty three samples of airborne particulate were collected every week at Ongkharak Nuclear Research Center (ONRC) during the period of June 1998 to March 1999. The Ti, I, Mg, Na, V, K, Cl, Al, Mn, Ca, As, Sm, Sb, Br, La, Ce, Th, Cr, Cs, Sc, Rb, Fe, Zn and Co were analyzed by Neutron Activation Analysis utilizing 2 MW TRIGA MARK III research reactor. The certified reference materials 1632a and 1633a from National Bureau of Standard were select as standard. (author)

  3. Human hair neutron activation analysis: analysis on population level, mapping

    International Nuclear Information System (INIS)

    Neutron activation analysis is an outstanding analytical method having very wide applications in various fields. Analysis of human hair within last decades mostly based on neutron activation analysis is a very attractive illustration of the application of nuclear analytical techniques. Very interesting question is how the elemental composition differs in different areas or cities. In this connection the present paper gives average data and maps of various localities in the vicinity of drying-out Aral Sea and of various industrial cities in Central Asia. (author)

  4. Establishment of rabbit radiation facility for neutron activation analysis

    International Nuclear Information System (INIS)

    The transfer principle and the composition of a rabbit radiation facility for neutron activation analysis in a reactor were introduced. The functions and security designs of the pneumatic transfer system and automatic control system in the irradiation device were studied. By the testing,the transfer speed of the facility is 7.0 m/s. The facility has advantages of steady transmission, simple operation, easy maintenance, etc. The facility satisfies the demand of the neutron activation analysis for short half-life nuclides. (authors)

  5. Activity report on neutron scattering research. V. 1, 1994

    International Nuclear Information System (INIS)

    In April, 1993, the Neutron Scattering Laboratory attached to the Institute for Solid State Physics, University of Tokyo, was newly established in Tokai, Ibaraki Prefecture, to promote nationwide users' programs for utilizing the university-owned neutron instruments installed at the JRR-3M reactor of Japan Atomic Energy Research Institute. This upgraded reactor (20 MW, the cold source is installed) has drastically expanded the number of users and research areas since 1990 when it became operational. Currently 8 and 3 out of 18 new spectrometers in total at the JRR-3M are owned by ISSP and Tohoku University, respectively, while the remaining 7 spectrometers belong to JAERI. In addition, 3 conventional spectrometers in the 30 years old JRR-2 reactor (10 MW) have also supported research activities. This is the first issue of 'Activity report on neutron scattering research', and it is to be published annually. In this report, the brief history of neutron scattering research, the users' programs, the committees, the neutron scattering instruments available at the JRR-3M and the JRR-2M, the activity reports on structures and excitation, magnetism, superconductors, liquid and glass, material science, polymers, biology and instrumentation, and publication list are reported. (K.I.)

  6. An Active Personal Dosemeter/Spectrometer for Neutrons

    International Nuclear Information System (INIS)

    A prototype of a highly sensitive active personal neutron dosemeter has been developed. It consists of a stack of four silicon detectors sandwiched between layers acting as neutron converters, moderators and absorbers. Its response to quasi-monoenergetic neutrons with energies up to 45 MeV and photons with energies up to 7 MeV has been measured and/or calculated for different angles of incident radiation. The personal dose equivalent determined from the reading obtained in some fields with broad energy distributions deviates by less than 30% from the reference values, both for normal incidence and incidence at 60 deg. to the normal. The detection threshold is about 3 μSv for fast neutrons, 1 μSv for intermediate neutrons and 0.007 μSv for thermal neutrons, even in mixed fields with a photon dose higher by a factor of 20. In addition, the evaluation procedures described give spectral and directional information about the field. (author)

  7. Studies of seaweeds as indicators of toxic element pollution in Ghana using neutron activation analysis

    International Nuclear Information System (INIS)

    The concentrations of 25 elements namely: AI, As, Br, Ca, Cd, CI, Co, Cr, Cu, Fe, Hf, Hg, I, K, La, Mg, Mn, Na, Ni, Sb, Sc, Sm, Sr, V and Zn in seven Rhodophyta (red), three Phaeophyta (brown) and five Chlorophyta (green) seaweed species from different areas along the coast of Ghana were determined by instrumental neutron activation analysis (INAA) and preconcentration NAA (PNAA). These species potentially could be used as biomonitors and bioremoval agents. The irradiations using thermal and epithermal neutrons were done using the Ghana Research Reactor-I (GHARR-I) facility at Ghana Atomic Energy Commission, Kwabenya and the Dalhousie University SLOWPOKE-2 Reactor (DUSR) facilities. Counting was done using both the conventional and anti-coincidence γ ray spectrometry. The PNAA method was developed for the simultaneous extraction of Cd, Cr, Hg, and Zn, as well as Sb and V individually from the seaweed samples. The PNAA method involved the use of a mixture of PAN and TAN chelating agents and PONPE-20 surfactant in cloud point extraction (CPE). The parameters affecting the CPE have been optimized. The recoveries under the optimum conditions of pH 3.7 for V, 6.4 for Sb, 8.6 for Cd, Cr, Hg, and Zn, [PAN/TAN] of 1x10-4M, [PONPE-20] of 0.1% (m/v), ionic strength 0.05 M KN03, and a temperature of 410C were generally >96%. The mean detection limits for Cd, Cr, Hg, Sb, V and Zn were 6.0, 3.6, 1.2, 2.8, 1.51 and 2.6 ng/g respectively. The CPE method developed was also used successfully to speciate As(III) and As(V) from the Sargassum vulgare, the seaweed. The maximum extraction of As(III) occurred at a pH of 6.7 and that of As(V) at pH of 3.8. The results indicated that As(III) and As(V) formed only 6.27% of the total arsenic concentration, while the other species of arsenic constitute 93.73%. The precision and accuracy of the INAA and PNAA methods developed were evaluated. Schewart control charts were constructed for internal quality assessment purposes. The results were

  8. Harmonised human biomonitoring in Europe

    DEFF Research Database (Denmark)

    Joas, Reinhard; Casteleyn, Ludwine; Biot, Pierre;

    2012-01-01

    Human biomonitoring (HBM) can be an effective tool to assess human exposure to environmental pollutants and potential health effects and is increasingly seen as an essential element in a strategy when integrating health and environment. HBM can be used (i) to prioritise actions and measures for...... policy making; (ii) to evaluate policy actions aimed at reducing exposure to potentially hazardous environmental stressors; and (iii) to promote more comprehensive health impact assessments of policy options. In support of the European Environment and Health Action Plan 2004-2010, European scientists......, experts from authorities and other stakeholders joined forces to work towards developing a functional framework and standards for a coherent HBM in Europe. Within the European coordination action on human biomonitoring, 35 partners from 27 European countries in the COPHES consortium aggregated their...

  9. Extraction of polychromatic thermal neutrons by Bragg diffraction to use for prompt gamma neutron activation analysis

    International Nuclear Information System (INIS)

    Extraction method of thermal neutron beam by Bragg diffraction is investigated. A thermal neutron beam is used for the Prompt Gamma Neutron Activation Analysis system at HANARO, a 30 MW research reactor in the Korea Atomic Energy Research Institute. Polychromatic beam including all orders of diffraction is obtained by setting a pair of pyrolytic graphite crystals with a Bragg angle of 45 deg. on a horizontal white beam line. Diffracted neutron flux at the sample position is calculated by considering the integrated reflectivity and mosaic spread of crystals. Due to the divergence effect, the mosaic spread of crystals is optimized to give the maximum and flat flux at the sample position. An experiment has been performed to verify the reflectivities for high order diffractions from pyrolytic graphite. When the focusing technique of bending the crystals is adopted, a design value of 1.0x108 n/cm2s is expected at the sample position. Hence Bragg diffraction is a promising method of extracting thermal neutrons for PGNAA

  10. Extraction of polychromatic thermal neutrons by Bragg diffraction to use for prompt gamma neutron activation analysis

    Science.gov (United States)

    Byun, S. H.; Choi, H. D.; Jun, B. J.; Kim, M. S.

    2000-07-01

    Extraction method of thermal neutron beam by Bragg diffraction is investigated. A thermal neutron beam is used for the Prompt Gamma Neutron Activation Analysis system at HANARO, a 30 MW research reactor in the Korea Atomic Energy Research Institute. Polychromatic beam including all orders of diffraction is obtained by setting a pair of pyrolytic graphite crystals with a Bragg angle of 45° on a horizontal white beam line. Diffracted neutron flux at the sample position is calculated by considering the integrated reflectivity and mosaic spread of crystals. Due to the divergence effect, the mosaic spread of crystals is optimized to give the maximum and flat flux at the sample position. An experiment has been performed to verify the reflectivities for high order diffractions from pyrolytic graphite. When the focusing technique of bending the crystals is adopted, a design value of 1.0×108n/cm2s is expected at the sample position. Hence Bragg diffraction is a promising method of extracting thermal neutrons for PGNAA.

  11. Advanced compact accelerator neutron generator technology for active neutron interrogation field work

    International Nuclear Information System (INIS)

    Due to a need for security screening instruments capable of detecting explosives and nuclear materials there is growing interest in neutron generator systems suitable for field use for applications broadly referred to as active neutron interrogation (ANI). Over the past two years Thermo Electron Corporation has developed a suite of different compact accelerator neutron generator products specifically designed for ANI field work to meet this demand. These systems incorporate hermetically-sealed particle accelerator tubes designed to produce fast neutrons using either the deuterium-deuterium (En = 2.5 MeV) or deuterium-tritium (En = 14.1 MeV) fusion reactions. Employing next-generation features including advanced sealed-tube accelerator designs, all-digital control electronics and innovative housing configurations these systems are suitable for many different uses. A compact system weighing less than 14 kg (MP 320) with a lifetime exceeding 1000 hours has been developed for portable applications. A system for fixed installations (P 325) has been developed with an operating life exceeding 4500 hours that incorporates specific serviceability features for permanent facilities with difficult-to-access shield blocks. For associated particle imaging (API) investigations a second-generation system (API 120) with an operating life of greater than 1000 hours has been developed for field use in which a high resolution fiberoptic imaging plate is specially configured to take advantage of a neutron point-source spot size of ∼2 mm. (author)

  12. Neutron induced activity in fuel element components

    International Nuclear Information System (INIS)

    A thorough investigation of the importance of various nuclides in neutron-induced radioactivity from fuel element construction materials has been carried out for both BWR and PWR fuel assemblies. The calculations were performed with the ORIGEN computer code. The investigation was directed towards the final storage of the assembly components and special emphasis was put to the examination of the sources of carbon-14, cobalt-60, nickel-59, nickel-63 and zirconium-93/niobium-93m. It is demonstrated that the nuclides nickel-59, in Inconel and stainless steel, and zirconium-93/niobium-93m, in Zircaloy, are the ones which constitute the very long term radiotoxic hazard of the irradiated materials. (author)

  13. Biomonitoring for the photovoltaics industry

    Energy Technology Data Exchange (ETDEWEB)

    Bernholc, N.M.; Moskowitz, P.D.

    1995-07-01

    Biomonitoring often is used as a method for estimating the dose to an individual. Therefore, a parameter of measurement, or biomarkers must be identified. The purpose of this paper is to give an overview of biomonitoring protocols for metals used in the photovoltaics industry. Special attention is given to areas that often are skimmed over, to gain insights into some of the problems that may arise when these tasks are carried out. Biological monitoring can be used to determine current human exposures to chemicals, as well as to detect past exposures, and the effects that these exposures may have on human health. It is used in conjunction with environmental monitoring to describe more completely worker`s exposures to, and absorption of, chemicals in the workplace. Biological specimens (e.g., blood, hair or urine) are analyzed for chemical agents, metabolites, or for some specific effect on the person (Lowry 1994). Biomonitoring can assess a workers exposure to industrial chemicals by all routes including skin absorption and ingestion. Although the methodology still is in its infancy, in cases where the procedures have been developed, it can be an invaluable component of an ongoing program of industrial hygiene monitoring. Like any technology, there are limitations to its effectiveness because of a lack of knowledge, contamination of specimens, and the introduction of errors.

  14. The multielement potential of fast neutron cyclic activation analysis

    International Nuclear Information System (INIS)

    Cyclic neutron activation analysis (CNAA) has, in recent years been developed as a useful analytical tool for the assay of short-lived isotopes in single element situations. The work described in this paper investigates the potential of the technique for composite samples having a wide range of elements that produce short-lived and long-lived isotopes on neutron irradiation. Accelerator-derived neutrons with average energies of 3 MeV, 6 MeV and 14 MeV were employed in what has been dubbed 'Fast Neutron Cyclic Neutron Activation Analysis' (FNCAA). The approach to multi-element analysis entailed: determination of cycle parameters in single element samples via the reactions 27Al(n,p)27Mg(9.6 min,Eγ=840keV), and 137Ba(n,n'γ137mBa(2.3 min,Eγ137mBa(2.3 min,Eγ=662 keV), a test of the method on a composite rock sample, determination of analytical sensitivities using both powdered kale and rock standards and a comparison of analytical results with other techniques. The results obtained in all these measurements are presented and discussed. (author) 10 refs.; 3 figs.; 5 tabs

  15. Validation of Numerical Simulations of Activation by Neutron Flux

    International Nuclear Information System (INIS)

    The knowledge of the radionuclide content of radioactive waste is of utmost importance for safety and waste management reasons. Numerical simulations are used at EDF-CIDEN to anticipate the dismantling and the radioactive waste management. The activation scheme by neutron flux developed at EDF-CIDEN comprises four steps: Step 1: Computing of a 3 dimensional multigroup neutron flux map. The mapping of the neutron flux is obtained on the basis of a neutron propagation calculation. The codes used are MCNP reference or TRIPOLI reference. Both solve the transport equation called the Boltzmann equation. The input data covers the microscopic cross-sections, the 3 dimensional geometry, the chemical compositions with no impurities and the computed neutron sources resulting in the neutrons emitted by the fuel assemblies. The neutron flux map is calculated at the nominal power rating conditions, and each flux is homogenized in a limited number of energy groups. Step 2: Calculation of the activities. The activities are calculated for each component or sub-component of interest. The code used is DARWIN-PEPIN (developed by the French CEA). It solves a system of Bateman equations. The input data covers the 3-dimensional neutron flux map calculated in step one, the microscopic cross sections, the radioactive decay series associated with the radioactive half-lives, the chemical compositions with impurities, and the history of irradiation resulting in the daily power production. The output data is the radioactive inventory of each component or sub-component of interest limited to a list of 143 radionuclides. Step 3: Waste classification. According to the radioactive inventory of each component or sub-component, and the waste classification criteria, a waste classification can be made. Basically the criteria are based on the levels of specific activity and radiotoxicity of 143 radionuclides. The distinction between the 'Long Life' and the 'Short Life' waste is

  16. Correlation study of air pollution and cardio-respiratory diseases through NAA of an atmospheric pollutant biomonitor

    International Nuclear Information System (INIS)

    In this study neutron activation analysis was applied to analyze lichen samples used as atmospheric pollutant biomonitors in order to verify if there is correlation between air pollution and its effects on the cardio respiratory system. Canoparmelia texana lichenized fungii species was chosen for passive biomonitoring of atmospheric pollutants. The population group selected for this study was adults over 45 years. Lichen samples collected in Sao Paulo city were cleaned, freeze-dried and ground for the analyses. Aliquots of samples were irradiated at the IEA-R1 nuclear research reactor for short and long periods along with synthetic element standards. The induced gamma activities of the samples and standards were measured using a gamma ray spectrometer with an HPGe detector and the concentrations of As, Ba, Br, Ca, Cd, Cl, Co, Cr, Cs, Fe, Hf, K, Mg, Mn, Na, Rb, Sb, Sc, Se,Th, V, Zn and lanthanides were determined. For quality control of the results, certified reference materials were analyzed together. Mortality data for the population due to cardio-respiratory diseases were obtained from the database of the Secretariat of Health of the Sao Paulo Municipality for the years 2005-2009. Results obtained point to vehicular and industrial emissions as the origins of pollutants in Sao Paulo city. The statistical treatment of Pearson's correlation applied to the results of lichen element concentrations and mortality rates indicated significant positive correlation for the elements Co, Mn and Zn for adults. (author)

  17. Neutron activation analysis - an aid to forensic science

    International Nuclear Information System (INIS)

    Forensic Science is oriented towards the examination of evidence specimens, collected from a scene of crime in order to establish the link between the criminal and the crime. This science therefore has a profound role to play in criminal justice delivery system. The importance of neutron activation analysis (NAA) as a specialised technique to aid crime investigation has emerged and has been recognised

  18. Determination of rhenium in molybdenite by neutron-activation analysis.

    Science.gov (United States)

    Terada, K; Yoshimura, Y; Osaki, S; Kiba, T

    1967-01-01

    A neutron-activation method is described for the determination of rhenium in molybdenite. Radiochemical separation by a carrier technique was carried out very rapidly by means of successive liquid-liquid extraction processes. The recovery of rhenium, which was determined by a spectrophotometric method, was about 93%. About 10 samples could be analysed within 6 hr in parallel runs. PMID:18960067

  19. Use of cyclotron-produced fast neutrons in activation analysis

    International Nuclear Information System (INIS)

    The determination of 15 elements: Pb, Sr, Ba, Ti, Ca, Sc, Cs, Zr, Rb, Cr, Se, Ni, Y, Co and Zn was investigated by fast neutron activation analysis using 80 MeV deuterons on various environmental samples. Detection limits of these elements from interference-free spectra were calculated. (author)

  20. Initial trials for in-house neutron activation analysis

    International Nuclear Information System (INIS)

    A range of elements in previously analysed rock samples have been assayed by neutron activation analysis and the practicality of performing such analyses at the Institute of Geological and Nuclear Sciences has been established. Further work is needed to fully refine the technique. A cost estimate has been made for a routine procedure. (author) 1 tab., 6 figs

  1. Neutron activation analysis of final molasses from the sugar industry

    International Nuclear Information System (INIS)

    Molasses samples from 74 factories were analyzed by neutron activation analysis. The concentration values of the 35 elements was determined. The toxicity and the influence of the presence of theses elements in sugar loss in the molasses and fermentative process is discussed

  2. Neutron activation analysis of different types of cuban sugar

    International Nuclear Information System (INIS)

    The Concentration of minor and trace elements in sugars (refined, crude and white-direct) from different Cuban mills were determined using instrumental neutron activation analysis with reactor, fourteen elements were fixed: Br, Ce, Co, Cr, Cs, Eu, Fe, La, Rb, Sc, Tb, Sr and Zn. The comparison of teh average concentration in sugar with another food samples is present

  3. Applied research of environmental monitoring using instrumental neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Young Sam; Moon, Jong Hwa; Chung, Young Ju

    1997-08-01

    This technical report is written as a guide book for applied research of environmental monitoring using Instrumental Neutron Activation Analysis. The contents are as followings; sampling and sample preparation as a airborne particulate matter, analytical methodologies, data evaluation and interpretation, basic statistical methods of data analysis applied in environmental pollution studies. (author). 23 refs., 7 tabs., 9 figs.

  4. Isotope identification of Langkawi black sand using neutron activation analysis

    International Nuclear Information System (INIS)

    The Langkawi black sand has been analyzed using the method of neutron activation analysis (INAA). A total of 22 elements have been detected. Elements such as Mn, Cu, Cr, U and Th occur in high concentration. Prospect for future mineralization of these elements may be of economic interest. (author) 9 refs.; 1 tab

  5. Progress in small angle neutron scattering activities in Malaysia

    International Nuclear Information System (INIS)

    The current status of SANS (Small Angle Neutron Scattering facility) activities in Malaysia has been presented. Many works need to be done for system improvement before the system can be confidently used as one of effective quality control tools in materials production and engineering sectors. (author)

  6. Instrumental Neutron Activation Analysis Technique using Subsecond Radionuclides

    DEFF Research Database (Denmark)

    Nielsen, H.K.; Schmidt, J.O.

    1987-01-01

    The fast irradiation facility Mach-1 installed at the Danish DR 3 reactor has been used in boron determinations by means of Instrumental Neutron Activation Analysis using12B with 20-ms half-life. The performance characteristics of the system are presented and boron determinations of NBS standard...

  7. Methodological developments and applications of neutron activation analysis

    Czech Academy of Sciences Publication Activity Database

    Kučera, Jan

    2007-01-01

    Roč. 273, č. 2 (2007), s. 273-280. ISSN 0236-5731 Institutional research plan: CEZ:AV0Z10480505 Keywords : neutron activation analysis * radiochemical separation Subject RIV: BE - Theoretical Physics Impact factor: 0.499, year: 2007

  8. Determination of iodine 129 in vegetables using neutron activation analysis

    International Nuclear Information System (INIS)

    The developed methodology allows the determination of iodine 129 in vegetables, using neutron activation analysis. The chemical treatment removes the interferences present in these matrixes, as well as the bromine 82 originated in the activation process. The experimental method for the determination of iodine 129 by neutron activation analysis involves five steps: 1- digestion by alkaline fusion; 2- pre-irradiation purification of iodine 129 by distillation followed by solvent extraction, and adsorption on activated charcoal by distillation; 3- neutron irradiation; 4- post-irradiation purification of iodine 130 by distillation followed by solvent extraction; 5- gamma spectrometry. A chemical recovery of 95 % is obtained in the distillations, measured using iodine 131 as tracer. The whole process recovery is within 70 % and 85 %. The detection limit is 2 mBq/kg of sample, but several factors affect this value, such as type of vegetable, natural iodine concentration, irradiation time and neutron flux. The methodology developed is applied at environmental surveillance with safeguards proposes, in the detection of undeclared reprocessing of irradiated fuel. (authors)

  9. The verification of neutron activation analysis support system (cooperative research)

    International Nuclear Information System (INIS)

    Neutron activation analysis support system is the system in which even the user who has not much experience in the neutron activation analysis can conveniently and accurately carry out the multi-element analysis of the sample. In this verification test, subjects such functions, usability, precision and accuracy of the analysis and etc. of the neutron activation analysis support system were confirmed. As a method of the verification test, it was carried out using irradiation device, measuring device, automatic sample changer and analyzer equipped in the JRR-3M PN-3 facility, and analysis software KAYZERO/SOLCOI based on the k0 method. With these equipments, calibration of the germanium detector, measurement of the parameter of the irradiation field and analysis of three kinds of environmental standard sample were carried out. The k0 method adopted in this system is primarily utilized in Europe recently, and it is the analysis method, which can conveniently and accurately carried out the multi-element analysis of the sample without requiring individual comparison standard sample. By this system, total 28 elements were determined quantitatively, and 16 elements with the value guaranteed as analytical data of the NIST (National Institute of Standards and Technology) environment standard sample were analyzed in the accuracy within 15%. This report describes content and verification result of neutron activation support system. (author)

  10. Analysis by neutron activation analysis a some ancient Dacian ceramics

    CERN Document Server

    Olariu, A

    1999-01-01

    Ancient Dacian ceramics, from three different establishments from Romanian territory have been analyzed by neutron activation analysis. A series of elements has been determined: Ba, Eu, K, La, Mn, Na, Sc, Sm. Ba is the element that could be considered to differentiate relatively the three groups of ceramics.

  11. Significance of neutron activation analysis in landscape geochemistry problem solution

    International Nuclear Information System (INIS)

    Employment of neutron activation analysis is of interest for solution of many theoretical and applied problems of landscape geochemistry. The role of the analysis in the study of rare and scattered element migration is quite significant. It is shown using gold, bromine, yttrium and rare earths as examples. 1 tab

  12. Mercury mass measurement in fluorescent lamps via neutron activation analysis

    Czech Academy of Sciences Publication Activity Database

    Viererbl, L.; Vinš, M.; Lahodová, Z.; Fuksa, A.; Kučera, Jan; Koleska, M.; Voljanskij, A.

    2015-01-01

    Roč. 116, NOV (2015), s. 56-59. ISSN 0969-806X R&D Projects: GA TA ČR TA01010237; GA MŠk LM2011019 Institutional support: RVO:61389005 Keywords : fluorescent lamp * mercury measurement * neutron activation analysis * research reactor Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.380, year: 2014

  13. Neutron activation analysis of chert artifacts from a Hopewell mound

    International Nuclear Information System (INIS)

    Six artifacts from a Hopewell mound located near Mt. Vernon, Indiana, and 21 geologic specimens from three different chert sources in the Ohio River Valley were analyzed by instrumental neutron activation analysis. Principal components analysis and posterior classification of the artifacts on the basis of Mahalanobis distance calculated probabilities were used to determine the most probable source for each of the artifacts. (author)

  14. Current status of neutron activation analysis in HANARO Research Reactor

    International Nuclear Information System (INIS)

    The facilities for neutron activation analysis in the HANARO (Hi-flux Advanced Neutron Application Research Reactor) are described and the main applications of NAA (Neutron Activation Analysis) are reviewed. The sample irradiation tube, automatic and manual pneumatic transfer system were installed at three irradiation holes of HANARO at the end of 1995. The performance of the NAA facility was examined to identify the characteristics of the tube transfer system, irradiation sites and custom-made polyethylene irradiation capsule. The available thermal neutron fluxes at irradiation sites are in the range of 3 x 1013 - 1 x 1014 n/cm2·s and cadmium ratios are in 15 - 250. For an automatic sample changer for gamma-ray counting, a domestic product was designed and manufactured. An integrated computer program (Labview) to analyse the content was developed. In 2001, PGNAA (Prompt Gamma Neutron Activation Analysis) facility has been installed using a diffracted neutron beam of ST1. NAA has been applied in the trace component analysis of nuclear, geological, biological, environmental and high purity materials, and various polymers for research and development. The improvement of analytical procedures and establishment of an analytical quality control and assurance system were studied. Applied research and development for the environment, industry and human health by NAA and its standardization were carried out. For the application of the KOLAS (Korea Laboratory Accreditation Scheme), evaluation of measurement uncertainty and proficiency testing of reference materials were performed. Also to verify the reliability and to validate analytical results, intercomparison studies between laboratories were carried out. (author)

  15. Current status of neutron activation analysis in HANARO Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Yong Sam; Moon, Jong Hwa; Sohn, Jae Min [Korea Atomic Energy Research Institute, Daejeon (Korea)

    2003-03-01

    The facilities for neutron activation analysis in the HANARO (Hi-flux Advanced Neutron Application Research Reactor) are described and the main applications of NAA (Neutron Activation Analysis) are reviewed. The sample irradiation tube, automatic and manual pneumatic transfer system were installed at three irradiation holes of HANARO at the end of 1995. The performance of the NAA facility was examined to identify the characteristics of the tube transfer system, irradiation sites and custom-made polyethylene irradiation capsule. The available thermal neutron fluxes at irradiation sites are in the range of 3 x 10{sup 13} - 1 x 10{sup 14} n/cm{sup 2}{center_dot}s and cadmium ratios are in 15 - 250. For an automatic sample changer for gamma-ray counting, a domestic product was designed and manufactured. An integrated computer program (Labview) to analyse the content was developed. In 2001, PGNAA (Prompt Gamma Neutron Activation Analysis) facility has been installed using a diffracted neutron beam of ST1. NAA has been applied in the trace component analysis of nuclear, geological, biological, environmental and high purity materials, and various polymers for research and development. The improvement of analytical procedures and establishment of an analytical quality control and assurance system were studied. Applied research and development for the environment, industry and human health by NAA and its standardization were carried out. For the application of the KOLAS (Korea Laboratory Accreditation Scheme), evaluation of measurement uncertainty and proficiency testing of reference materials were performed. Also to verify the reliability and to validate analytical results, intercomparison studies between laboratories were carried out. (author)

  16. Neutron activation: an invaluable technique for teaching applied radiation

    International Nuclear Information System (INIS)

    This experiment introduces students to the important method of neutron activation. A sample of aluminium was irradiated with neutrons from an isotropic 241Am-Be source. Using γ-ray spectroscopy, two radionuclide products were identified as 27Mg and 28Al. Applying a cadmium cut-off filter and an optimum irradiation time of 45 min, the half-life of 27Mg was determined as 9.46±0.50 min. The half-life of the 28Al radionuclide was determined as 2.28±0.10 min using a polythene moderator and an optimum irradiation time of 10 min. (author)

  17. Determination of thorium in human urine by neutron activation

    International Nuclear Information System (INIS)

    A routine procedure for the determination of thorium in urine of workers has been developed by the neutron activation method. The technique suggested by Dang, et. al. has been modified in order to reduce the cost involved and the sample processing time. The samples were irradiated in the MIT (Massachusetts Institute of Technology-Boston) reactor, in a thermal neutron flux of 8 x 10 12n.cm-2.s-1 for 3,5 hours. Thorium-232 was determined by counting 233Pa. (author) 6 refs.; 2 tabs

  18. The comparison of four neutron sources for Prompt Gamma Neutron Activation Analysis (PGNAA) in vivo detections of boron

    International Nuclear Information System (INIS)

    A Prompt Gamma Ray Neutron Activation Analysis (PGNAA) system, incorporating an isotopic neutron source has been simulated using the MCNPX Monte Carlo code. In order to improve the signal to noise ratio different collimators and a filter were placed between the neutron source and the object. The effect of the positioning of the neutron beam and the detector relative to the object has been studied. In this work the optimisation procedure is demonstrated for boron. Monte Carlo calculations were carried out to compare the performance of the proposed PGNAA system using four different neutron sources (241Am/Be, 252Cf, 241Am/B, and DT neutron generator). Among the different systems the 252Cf neutron based PGNAA system has the best performance. (author)

  19. Prototyping an Active Neutron Veto for SuperCDMS

    Energy Technology Data Exchange (ETDEWEB)

    Calkins, Robert [Southern Methodist U.; Loer, Ben [Fermilab

    2015-08-17

    Neutrons, originating cosmogenically or from radioactive decays, can produce signals in dark matter detectors that are indistinguishable from Weakly Interacting Massive Particles (WIMPs). To combat this background for the SuperCDMS SNOLAB experiment, we are investigating designs for an active neutron veto within the constrained space of the compact SuperCDMS passive shielding. The current design employs an organic liquid scintillator mixed with an agent to enhance thermal neutron captures, with the scintillation light collected using wavelength-shifting fibers and read out by silicon photo-multipliers. We will describe the proposed veto and its predicted efficiency in detail and give some recent results from our R&D and prototyping efforts.

  20. The activation method for determining neutron spectra and fluences

    International Nuclear Information System (INIS)

    3 mm thick foils of 4 and 17 mm in diameter were used for measurements. NaI scintillation detectors 45 mm in diameter by 50 mm thick and 40 mm in diameter by 1 mm thick, and a Ge-Li spectrometer of 53 cm3 in volume were used for gamma detection. A photopeak or a certain part of the integral spectrum was measured for each radionuclide. Computer code PIKAR was applied in automatic calculation of a simple gamma spectrum obtained using the semiconductor spectrometer. The FACT code was used for calculating foil activity. Codes SAND II and RFSP were used for neutron spectra unfolding. Ge-Li detector spectrometry was used for determining neutron fluence. Code FLUE was used for determining the mean value of neutron flux density and fluence. (J.P.)

  1. Prototyping an active neutron veto for SuperCDMS

    Energy Technology Data Exchange (ETDEWEB)

    Calkins, Robert [Department of Physics, Southern Methodist University, Dallas, Texas 75275 (United States); Loer, Ben [Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)

    2015-08-17

    Neutrons, originating cosmogenically or from radioactive decays, can produce signals in dark matter detectors that are indistinguishable from Weakly Interacting Massive Particles (WIMPs). To combat this background for the SuperCDMS SNOLAB experiment, we are investigating designs for an active neutron veto within the constrained space of the compact SuperCDMS passive shielding. The current design employs an organic liquid scintillator mixed with an agent to enhance thermal neutron captures, with the scintillation light collected using wavelength-shifting fibers and read out by silicon photo-multipliers. We will describe the proposed veto and its predicted efficiency in detail and give some recent results from our R&D and prototyping efforts.

  2. Radioactive waste package assay facility. Volume 2. Investigation of active neutron and active gamma interrogation

    International Nuclear Information System (INIS)

    Volume 2 of this report describes the theoretical and experimental work carried out at Harwell on active neutron and active gamma interrogation of 500 litre cemented intermediate level waste drums. The design of a suitable neutron generating target in conjunction with a LINAC was established. Following theoretical predictions of likely neutron responses, an experimental assay assembly was built. Responses were measured for simulated drums of ILW, based on CAGR, Magnox and PCM wastes. Good correlations were established between quantities of 235-U, nat-U and D2O contained in the drums, and the neutron signals. Expected sensitivities are -1g of fissile actinide and -100g of total actinide. A measure of spatial distribution is obtainable. The neutron time spectra obtained during neutron interrogation were more complex than expected, and more analysis is needed. Another area of discrepancy is the difference between predicted and measured thermal neutron flux in the drum. Clusters of small 3He proportional counters were found to be much superior for fast neutron detection than larger diameter counters. It is necessary to ensure constancy of electron beam position relative to target(s) and drum, and prudent to measure the target neutron or gamma output as appropriate. 59 refs., 77 figs., 11 tabs

  3. Active Interrogation Using Electronic Neutron Generators for Nuclear Safeguards Applications

    Energy Technology Data Exchange (ETDEWEB)

    David L. Chichester; Edward H. Seabury

    2008-08-01

    Active interrogation, a measurement technique which uses a radiation source to probe materials and generate unique signatures useful for characterizing those materials, is a powerful tool for assaying special nuclear material. The most commonly used technique for performing active interrogation is to use an electronic neutron generator as the probe radiation source. Exploiting the unique operating characteristics of these devices, including their monoenergetic neutron emissions and their ability to operate in pulsed modes, presents a number of options for performing prompt and delayed signature analyses using both photon and neutron sensors. A review of literature in this area shows multiple applications of the active neutron interrogation technique for performing nuclear nonproliferation measurements. Some examples include measuring the plutonium content of spent fuel, assaying plutonium residue in spent fuel hull claddings, assaying plutonium in aqueous fuel reprocessing process streams, and assaying nuclear fuel reprocessing facility waste streams to detect and quantify fissile material. This paper discusses the historical use of this technique and examines its context within the scope and challenges of next-generation nuclear fuel cycles and advanced concept nuclear fuel cycle facilities.

  4. Active Interrogation Using Electronic Neutron Generators for Nuclear Safeguards Applications

    Science.gov (United States)

    Chichester, D. L.; Seabury, E. H.

    2009-03-01

    Active interrogation, a measurement technique which uses a radiation source to probe materials and generate unique signatures useful for characterizing those materials, is a powerful tool for assaying special nuclear material. The most commonly used technique for performing active interrogation is to use an electronic neutron generator as the probe radiation source. Exploiting the unique operating characteristics of these devices, including their monoenergetic neutron emissions and their ability to operate in pulsed modes, presents a number of options for performing prompt and delayed signature analyses using both photon and neutron sensors. A review of literature in this area shows multiple applications of the active neutron interrogation technique for performing nuclear nonproliferation measurements. Some examples include measuring the plutonium content of spent fuel, assaying plutonium residue in spent fuel hull claddings, assaying plutonium in aqueous fuel reprocessing process streams, and assaying nuclear fuel reprocessing facility waste streams to detect and quantify fissile material. This paper discusses the historical use of this technique and examines its context within the scope and challenges of next-generation nuclear fuel cycles and advanced concept nuclear fuel cycle facilities.

  5. Determination of copper in some Myanmar indigenous medicines by neutron activation analysis

    International Nuclear Information System (INIS)

    Copper was determined in two Myanmar indigenous medicines by neutron activation analysis using an Am(Be) radionuclide neutron source. The activity of 511 keV peak of the 64Cu was measured. (author) 2 refs.; 2 tabs

  6. Communication in a Human biomonitoring study

    DEFF Research Database (Denmark)

    Exley, Karen; Cano, Noemi; Aerts, Dominique;

    2015-01-01

    A communication strategy was developed by The Consortium to Perform Human Biomonitoring on a European Scale (COPHES), as part of its objectives to develop a framework and protocols to enable the collection of comparable human biomonitoring data throughout Europe. The framework and protocols were...... tested in the pilot study DEMOCOPHES (Demonstration of a study to Coordinate and Perform Human biomonitoring on a European Scale). The aims of the communication strategy were to raise awareness of human biomonitoring, encourage participation in the study and to communicate the study results...... and stakeholders, followed by dissemination at European level. Several lessons were learnt that may assist other future human biomonitoring studies. Recruitment took longer than anticipated and so social scientists, to help with community engagement, should be part of the research team from the start...

  7. Neutron activation analysis of cadmium in Jamaican soils

    International Nuclear Information System (INIS)

    A procedure for the instrumental neutron activation analysis of Cd in soils with relatively high Cd content and possible interferences is reported. Cadmium concentrations in Jamaican soils above 4 mg x kg-1 can now be reliably determined by multielemental instrumental activation analysis with an accuracy ±10% and the reasonably high throughput of 30 samples per day. Over 600 geochemical survey samples were analysed for Cd along with some 20 other long-lived elements. (author)

  8. Neutron imaging and prompt gamma activation analysis using a monolithic capillary neutron lens

    International Nuclear Information System (INIS)

    Neutron focusing lenses have been shown to enhance the measurement capabilities of prompt gamma activation analysis (PGAA) for small samples (∼100 μm in size) using a reactor-based cold neutron beam. As reported in our earlier work, a cold neutron beam emerging from a 58Ni-coated guide, cross section 50 mm x 45 mm, is compressed to a spot size of about 0.54 mm (FWHM). In the current work, we report preliminary prompt gamma measurements performed with a monolithic capillary lens that accepts a 10 mm (hexagon flat-to-flat) size beam and focuses it to a spot size of 40. The smaller focal spot size enables better spatial resolution, but also makes sample alignment more challenging. We have added a neutron imaging technique to the sample positioning procedure that takes advantage of the converging and subsequent diverging nature of the focused beam. The measurement sensitivity for a 2.6 μg Gd sample has improved by a factor of 34. In addition to rastering samples in the lateral plane, we have also explored the possibility of profiling the inhomogeneity of the sample in the direction along the beam axis. (author)

  9. Intercomparison of Neutron Beam Guides for Cold Neutron Activation Station at HANARO using McStas/VITESS/RESTRAX Codes

    Energy Technology Data Exchange (ETDEWEB)

    Tuan, Hoang Sy Minh; Sun, Gwang Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-05-15

    The HANARO (KAERI) research reactor has been developed a neutron guide system for cold neutron (CN) research facilities since July, 2003. The neutron guide system plays an important role in transporting cold neutrons from the CN source to the neutron facilities as CN-NDP, CN-PGAA, SANS, etc. The CN activation station is being installed in the HANARO cold-neutron research project. The CN-NDP and CN-PGAA were selected as two facilities using at this station. At the end position of CG1 and CG2B beam guides, the CN-NDP and CN-PGAA will be installed in the CN guide hall. In order to predict the neutron flux and intensity values at the CG1 and CG2B beam guides, the simulation results of neutron flux at the CG1 and CG2B beam guides are presented by using several Monte Carlo (MC) neutron ray-tracing simulation codes. The intercomparison of neutron flux values between McStas, VITESS and RESTRAX are performed for getting fairly correct results at two neutron beam guides

  10. Measurement of neutron activation in concrete samples

    International Nuclear Information System (INIS)

    The results of activation studies of ordinary and barytes concrete samples relevant for research reactor decommissioning are given. Five important long-lived radioactive isotopes (54Mn, 60Co, 65Zn, 133Ba, and 152Eu) were identified from the gamma-ray spectra measured in the irradiated concrete samples. Activation of these samples was also calculated using ORIGEN2 code. Comparison of calculated and measured results is given. (author)

  11. Analysis of human enamel and dentine by neutron activation analysis

    International Nuclear Information System (INIS)

    Determination of trace elements in dental tissues has been of great interest to study the correlation between element composition and caries as well as food habits of individuals. In the present study dentine and enamel samples from healthy individuals were analysed by neutron activation analysis. The teeth were provided form dental clinics, and they were previously washed using purified water and acetone. Then they were dried at 40 deg C and ground in a agate mortar. The samples and element standards were irradiated with thermal neutrons at the IEA-R1 nuclear reactor. Long irradiations of 8 h under thermal neutron flux of 5x1012 n cm-2 s-1 were used for Ca, Na, Sr and Zn determinations. In short irradiations of 15 s and under neutron flux of 1012 n cm-2 s-1 the elements Mg, Mn, Na e Sr were determined. The induced gamma activities of the samples and standards were measured using a hyperpure Ge detector coupled to a gamma ray spectrometer. Elemental concentrations were calculated by comparative method. Results obtained showed that Ca, Mg and Na are present in both tissues at the level of percentages and the elements Mn, Sr and Zn at the μg g-1 levels. For quality control of the results the certified reference materials NIST 1400 Bone Ash and NIST 1486 Bone Meal were analysed. (author)

  12. The monostandard method in thermal neutron activation analysis

    International Nuclear Information System (INIS)

    A simple method is described for instrumental multielement thermal neutron activation analysis using a monostandard. For geological and air dust samples, iron is used as a comparator, while sodium has advantages for biological materials. To test the capabilities of this method, the values of the effective cross sections of the 23 elements determined were evaluated in a reactor site with an almost pure thermal neutron flux of about 9 x 1012 n x cm-2 x sec-1 and an epithermal neutron contribution of less than 0,03%. The obtained values were found to agree mostly well with the literature best values of thermal neutron cross sections. The results of an analysis by activation in the same site agree well with the relative method using multielement standard and for several standard reference materials with certified element contents. A comparison of the element contents obtained by the monostandard and relative methods together with corresponding precisions and accuracies is given. A brief survey of the monostandard method is presented. (orig.)

  13. Laboratory of neutron activation analysis at the Nuclear Physics Institute ASCR, Řež

    Czech Academy of Sciences Publication Activity Database

    Kučera, Jan

    2011-01-01

    Roč. 21, č. 1 (2011), s. 30-35. ISSN 1061-9127 Institutional research plan: CEZ:AV0Z10480505 Keywords : Instrumental neutron activation analysis * epithermal neutron activation analysis * radiochemical neutron activation analysis * applications in science and technology Subject RIV: BG - Nuclear, Atomic and Molecular Physics , Colliders

  14. Sol particle immunoassays using colloidal gold and neutron activation

    International Nuclear Information System (INIS)

    The feasibility of performing immunoassays with colloidal gold labels and detection of 198Au by neutron activation has been demonstrated with measurements of human immunoglobulin and of serum antibodies to human immunodeficiency virus type 1. The detection sensitivity achieved after activation in a high flux reactor or with a water moderated 252Cf source, by gamma-counting or by autoradiography, is similar to the sensitivity obtained with absorbance measurements in the more common enzyme immunoassays. The reactor based neutron activation assay allows detection of 10-16 mol of analyte in routine operation with possible extension to 10-20 mol. The sensitivity with the 1.3 Ci 252 Cf source is limited to about 10-15 mol. The practical limitations of the assay's sensitivity at this point are due to background signals from reagents and/or nonspecific binding of the gold labeled reagent. (author) 13 refs.; 2 figs.; 1 tab

  15. Fast-neutron activation analysis of manganese nodules

    International Nuclear Information System (INIS)

    The present paper describes the development of a new nuclear method that allows rapid determinations of the most relevant metals Ni and Cu without sample treatment, thus being particularly suited for quasi-continuous elemental analyses in mining and processing. The measurement is based on fast-neutron activation using Cockcroft-Walton generators, sealed neutron tubes or, possibly, (α,n)-type natural sources. Fast-neutron activation of manganese nodules is dominated by the (n,p)-reactions on Si, Al, Fe; the (n,α)-reaction on Mn and the (n,2n)-reaction on Cu. By choosing appropriate irradiation and cooling periods gamma-ray activities with comparatively simple spectral distributions are induced. From these spectra the Mn/Fe ratio in the nodules can be determined without the elaborate procedures usually required in absolute methods for eliminating systematic errors from fluctuations in sample and/or irradiation parameters. It is connected with the absolute Ni and Cu contents via well-known geochemical correlations which according to a lot of statistical data apply to quite different deposits and nodule types in the Pacific. Using these correlations the determination of the most important metals reduces to the evaluation of a peak area ratio. Measurements of the neutron flux distribution and the apparent sample density are unnecessary. The simple structure of the spectra allows the application of detectors with modest energy resolution, e.g. scintillation counters which can be manufactured as ruggedized crystal assemblies with great resistance to thermal and mechanical shock. The method is described in detail and possible interference, in particular from thermal and epithermal neutrons, are discussed. (orig.)

  16. Some Applications of Fast Neutron Activation Analysis of Oxygen

    International Nuclear Information System (INIS)

    In this thesis we focus on applications of neutron activation of oxygen for several purposes: A) measuring the water level in a laboratory tank, B) measuring the water flow in a pipe system set-up, C) analysing the oxygen in combustion products formed in a modern gasoline SI engine, and D) measuring on-line the amount of oxygen in bulk liquids. A) Water level measurements. The purpose of this work was to perform radiation based water level measurements, aimed at nuclear reactor vessels, on a laboratory scale. A laboratory water tank was irradiated by fast neutrons from a neutron generator. The water was activated at different water levels and the water level was decreased. The produced gamma radiation was measured using two detectors at different heights. The results showed that the method is suitable for measurement of water level and that a relatively small experimental set-up can be used for developing methods for water level measurements in real boiling water reactors based on activated oxygen in the water. B) Water flows in pipe. The goal in this work was to investigate the asymmetric distribution of activity in flow measurements with pulsed neutron activation (PNA) in a laboratory piping system. Earlier investigations had shown a discrepancy between the measured velocity of the activated water by PNA and the true mean velocity in the pipe. This discrepancy decreased with larger distances from the activation point. It was speculated that the induced activity in the pipe did not distribute homogeneously. With inhomogeneous radial distribution of activity in combination with a velocity profile in the pipe, the activated water may not have the same velocity as the mean velocity of water in the pipe. To study this phenomenon, a water-soluble colour was injected into a transparent pipe for simulation of the transport of the activated water. The radial concentration of the colour, at different distances from the activation point, was determined. The result

  17. Some Applications of Fast Neutron Activation Analysis of Oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Owrang, Farshid

    2003-07-01

    In this thesis we focus on applications of neutron activation of oxygen for several purposes: A) measuring the water level in a laboratory tank, B) measuring the water flow in a pipe system set-up, C) analysing the oxygen in combustion products formed in a modern gasoline SI engine, and D) measuring on-line the amount of oxygen in bulk liquids. A) Water level measurements. The purpose of this work was to perform radiation based water level measurements, aimed at nuclear reactor vessels, on a laboratory scale. A laboratory water tank was irradiated by fast neutrons from a neutron generator. The water was activated at different water levels and the water level was decreased. The produced gamma radiation was measured using two detectors at different heights. The results showed that the method is suitable for measurement of water level and that a relatively small experimental set-up can be used for developing methods for water level measurements in real boiling water reactors based on activated oxygen in the water. B) Water flows in pipe. The goal in this work was to investigate the asymmetric distribution of activity in flow measurements with pulsed neutron activation (PNA) in a laboratory piping system. Earlier investigations had shown a discrepancy between the measured velocity of the activated water by PNA and the true mean velocity in the pipe. This discrepancy decreased with larger distances from the activation point. It was speculated that the induced activity in the pipe did not distribute homogeneously. With inhomogeneous radial distribution of activity in combination with a velocity profile in the pipe, the activated water may not have the same velocity as the mean velocity of water in the pipe. To study this phenomenon, a water-soluble colour was injected into a transparent pipe for simulation of the transport of the activated water. The radial concentration of the colour, at different distances from the activation point, was determined. The result

  18. Electronic dosimetry and neutron metrology by CMOS active pixel sensor

    International Nuclear Information System (INIS)

    This work aims at demonstrating the possibility to use active pixel sensors as operational neutron dosemeters. To do so, the sensor that has been used has to be γ-transparent and to be able to detect neutrons on a wide energy range with a high detection efficiency. The response of the device, made of the CMOS sensor MIMOSA-5 and a converter in front of the sensor (polyethylene for fast neutron detection and 10B for thermal neutron detection), has been compared with Monte Carlo simulations carried out with MCNPX and GEANT4. These codes have been before-hand validated to check they can be used properly for our application. Experiments to characterize the sensor have been performed at IPHC and at IRSN/LMDN (Cadarache). The results of the sensor irradiation to photon sources and mixed field (241AmBe source) show the γ-transparency of the sensor by applying an appropriate threshold on the deposited energy (around 100 keV). The associated detection efficiency is satisfactory with a value of 10-3, in good agreement with MCNPX and GEANT4. Other features of the device have been tested with the same source, like the angular response. The last part of this work deals with the detection of thermal neutrons (eV-neutrons). Assays have been done in Cadarache (IRSN) with a 252Cf source moderated with heavy water (with and without cadmium shell). Results asserted a very high detection efficiency (up to 6*10-3 for a pure 10B converter) in good agreement with GEANT4. (author)

  19. Algae as Bio-monitors for Damodar River Water Pollution

    OpenAIRE

    S. Lata Dora; Maiti, S. K.; R. K.Tiwary; Anshumali Singh

    2015-01-01

    Damodar is an important tributary of Ganga river basin and cater the needs of industries and growing human population in the eastern part of India. Assessment of algal diversity was carried out to understand the impact of coal mining and allied industrial activities on the ecological condition of Damodar river basin. Surface water and algal samples were collected in the summer (2009) from ten sites along the Damodar River. Bio-monitoring of algal diversity showed high organic pollution load i...

  20. Design of a neutron activation system around a DD neutron generator by an analytical method and Monte Carlo simulation

    International Nuclear Information System (INIS)

    Recent developments in neutron generator technology suggest that compact instruments with high neutron yield can be used for NAA and PGNAA in combination with high count rate spectrometers. For laboratories far away from Research Reactors (RRs), such devices could serve as an alternative for training students in radioanalytical and nuclear Chemistry and certain specialized applications. As Neutron activation analysis is a well established technique with a long history of documented applications it could be made available to countries where no research reactors or other neutron irradiation facilities exist by using the proposed approach. Prompt gamma neutron activation analysis (PGNAA) is a versatile analytical tool with many applications unique to the technique. As PGNAA is generally performed at RRs external neutron guides with relatively low N flux, the proposed instrument has a potential to supplement existing PGNAA facilities far away from RRs. Neutron generators, particularly the DD-NGs, are a cost effective, easy to operate and particularly safe alternative to other neutron sources, e.g. isotopic neutron sources like Cf-252 or Am/Be. The idea to combine new developments in DD-NG with moderator/shielding and detectors for fast gamma counting emerged from a recent IAEA Coordinated Research Project (CRP) on New Developments in PGNAA, and an IAEA technical meeting on Neutron Generators for Activation Analysis Purposesis currently under preparation. We report on the design and optimization of a Neutron Activation Analysis (NAA) and a Prompt Gamma Neutron Activation Analysis (PGNAA) chamber associated with a D-D neutron generator. The nominal yield of the generator is about 1010 fast neutrons per seconds (E=2.5MeV). MCNP-Monte Carlo N-Particle Transport simulation code and analytical equation, are used to optimize the setup with respect to thermal flux and radiation protection. Many moderators such as Graphite (G), Polyethylene (Poly), Heavy water (HW), Light water

  1. Activity report of the fusion neutronics source from April 1, 2001 to March 31, 2004

    International Nuclear Information System (INIS)

    The Fusion Neutronics Source (FNS) is an accelerator based 14 MeV neutron generator established in 1981. FNS is a powerful tool for neutronics research aiming the fusion reactor development such as neutron cross section measurements, integral experiments and blanket neutronics experiments. This report reviews the FNS activities in the period from April 1, 2001 to March 31, 2004, including collaboration with universities and other research institutes. The 35 papers are indexed individually. (J.P.N.)

  2. Neutron activation analysis of essential elements in Multani mitti clay using miniature neutron source reactor

    International Nuclear Information System (INIS)

    Multani mitti clay was studied for 19 essential and other elements. Four different radio-assay schemes were adopted for instrumental neutron activation analysis (INAA) using miniature neutron source reactor. The estimated weekly intakes of Cr and Fe are high for men, women, pregnant and lactating women and children while intake of Co is higher in adult categories and Mn by pregnant women. Comparison of MM clay with other type of clays shows that it is a good source of essential elements. - Highlights: ► Multani mitti clay has been studied for 19 essential elements for human adequacy and safety using INAA and AAS. ► Weekly intakes for different consumer categories have been calculated and compared with DRIs. ► Comparison of MM with other type of clays depict that MM clay is a good source of essential elements.

  3. The possible discovery of neutron activation in 1910

    International Nuclear Information System (INIS)

    One-hundred-two years ago, on 21 April 1910, the Austrian chemist Carl Auer von Welsbach published a short comment on a fundamental discovery he had made in the field of nuclear sciences. He reported that 'jonium' (230Th) was able to induce radioactivity in other materials if stored in contact with the ionium sample. He was well aware that this observation was 'not quite in agreement with current theories', because, as a basic principle, a radioactive substance cannot activate an inactive substance. Since he could not remove any superficial contamination, he concluded that the previously inactive materials had become radioactive themselves. Auer von Welsbach predicted that this observation 'might be of importance for the mysterious field of radioactivity research'. In fact, we believe that in this experiment he incidentally discovered neutron activation and the production of artificial radionuclides (24 years before I. Curie and F. Joliot) or even induced nuclear fission. The neutron source in his experiments is yet unknown and shall be identified in this project. The neutrons could have been produced from nuclear reactions with impurities of beryllium in the sample. Auer von Welsbach may even have observed nuclear fission 29 years before O. Hahn, F. Strassmann, L. Meitner and O. R. Frisch. In any case, he may have noticed the effects of neutron radiation-22 years before its discovery by J. Chadwick. The main aim of this interdisciplinary project (of which preliminary results are presented herein) is to repeat the 1910-experiment and to identify the source of the neutrons. It will be equally important to investigate the historical reasons and circumstances why Auer's report remained mostly uncommented in the scientific community. The hypothetical consequences are worth discussion: Auer's publication could have started the 'nuclear age' much earlier than it finally began, with all the consequences for mankind. (author)

  4. Simulation for sodium-24 production using cyclic neutron activation analysis

    International Nuclear Information System (INIS)

    The cyclic neutron activation analysis is a method for elemental analysis which is preferred to use short-lived radio-nuclides. In recent years this method became a new application for radioisotope production especially in low power research reactors. In this study instrumental cyclic neutron activation analysis was used for 24Na production using 23Na (n, γ) 24Na reaction. The simplified westcott convention method is used neutron activation analysis in a research reactor. The method takes into account all corrections that can affect that yield created. In this work a model was devolving for calculations through this simplified Westcott convention method by using C++ program and selecting good parameters that can produce the expected activity. The simulation is used for the theoretical yield calculated has been validated by data from the 177Lu production used for theoretical yield which it gives the approached result had been obtained by FORTRAN 90 from literature (8). The results were achieved for expected activity at full power (1 x 10 12n cm-2 s-1) and half power (5 x 1011 cm-2 s-1) for research reactor MNSR. The activity at full power was equal to about twice the activity at half power ( 49±7, 24.9 ± MBq/g), respectively. The irradiation parameters selected were irradiation time 4 min and decay time 12 min. Sample weight was 50 mg at 12 numbers of cycles, when the K-factor was equal to 1.74. This work is considered as first step for production of 24Na which can use such parameters experimentally. It is then possible to compare the expected activity with measured activity. (Author)

  5. Applied research and development of neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Yong Sam; Moon, Jong Hwa; Kim, Sun Ha; Baek, Sung Ryel; Kim, Young Gi; Jung, Hwan Sung; Park, Kwang Won; Kang, Sang Hun; Lim, Jong Myoung

    2003-05-01

    The aims of this project are to establish the quality control system of Neutron Activation Analysis(NAA) due to increase of industrial needs for standard analytical method and to prepare and identify the standard operation procedure of NAA through practical testing for different analytical items. R and D implementations of analytical quality system using neutron irradiation facility and gamma-ray measurement system and automation of NAA facility in HANARO research reactor are as following ; 1) Establishment of NAA quality control system for the maintenance of best measurement capability and the promotion of utilization of HANARO research reactor 2) Improvement of analytical sensitivity for industrial applied technologies and establishment of certified standard procedures 3) Standardization and development of Prompt Gamma-ray Activation Analysis (PGAA) technology.

  6. Applied research and development of neutron activation analysis

    International Nuclear Information System (INIS)

    The aims of this project are to establish the quality control system of Neutron Activation Analysis(NAA) due to increase of industrial needs for standard analytical method and to prepare and identify the standard operation procedure of NAA through practical testing for different analytical items. R and D implementations of analytical quality system using neutron irradiation facility and gamma-ray measurement system and automation of NAA facility in HANARO research reactor are as following ; 1) Establishment of NAA quality control system for the maintenance of best measurement capability and the promotion of utilization of HANARO research reactor 2) Improvement of analytical sensitivity for industrial applied technologies and establishment of certified standard procedures 3) Standardization and development of Prompt Gamma-ray Activation Analysis (PGAA) technology

  7. Neutron activation analysis applied to nutritional and foodstuff studies

    International Nuclear Information System (INIS)

    Neutron Activation Analysis, NAA, has been successfully used on a regularly basis in several areas of nutrition and foodstuffs. NAA has become an important and useful research tool due to the methodology's advantages. These include high accuracy, small quantities of samples and no chemical treatment. This technique allows the determination of important elements directly related to human health. NAA also provides data concerning essential and toxic concentrations in foodstuffs and specific diets. In this paper some studies in the area of nutrition which have been carried out at the Neutron Activation Laboratory of IPEN/CNEN-SP will be presented: a Brazilian total diet study: nutritional element dietary intakes of Sao Paulo state population; a study of trace element in maternal milk and the determination of essential trace elements in some edible mushrooms. (author)

  8. Neutron activation analysis of traces of metallic elements in water

    International Nuclear Information System (INIS)

    The application of neutron activation analysis is examined for the elements iron, nickel, chromium and cobalt which are constituents of the aqueous corrosion products of stainless steels and which are present in very low concentrations in the water used in the heat transfer systems of nuclear reactors. The best results were obtained by slow evaporation of the water sample in a quartz ampoule in an oven followed by irradiation of the dry sample in the same ampoule. The problems of blanks, of losses during concentration, and of conservation of solutions at very low concentrations were studied. Good agreement was found between the theoretical quantities and experimental results with standard samples containing 50ppb of each of the studied elements. There was also excellent agreement between neutron activation and spectrophotometric methods in the case of determinations of iron in solution

  9. Practical aspects of operating a neutron activation analysis laboratory

    International Nuclear Information System (INIS)

    This book is intended to advise in everyday practical problems related to operating a neutron activation analysis (NAA) laboratory. It gives answers to questions like ''what to use NAA for'', ''how to find relevant research problems'', ''how to find users for the technique'', ''how to estimate the cost of the analysis and how to finance the work'', ''how to organize the work in a rational way'' and ''how to perform the quality control''. It gives advice in choosing staff, equipment, and consumables and how to design facilities and procedures according to need and available resources. Potential applications of economic or environmental importance, reactor facilities, counting and measuring equipment of the lab, cooperation with other analytical groups and competitiveness of NAA are discussed by experienced analysts. The compiled 8 tables of data useful for neutron activation analysts are a valuable asset for research labs as well as industrial quality control units. Refs, figs and tabs

  10. Nondestructive neutron activation analysis of volcanic samples: Hawaii

    International Nuclear Information System (INIS)

    Samples of volcanic emissions have been collected between and during eruptions of both Kilauea and Mauna Loa volcanoes during the last three years. Airborne particles have been collected on Teflon filters and acidic gases on base-impregnated cellulose filters. Chemically neutral gas-phase species are collected on charcoal-coated cellulose filters. The primary analytical technique used is nondestructive neutron activation analysis, which has been used to determine the quantities of up to 35 elements on the different filters. The use of neutron activation analysis makes it possible to analyze for a wide range of elements in the different matrices used for the collection and to learn about the distribution between particles and gas phases for each of the elements

  11. Determination of sodium in pharmaceuticals by neutron activation analysis

    International Nuclear Information System (INIS)

    A simple, fast and accurate neutron activation analysis method for determination of Na in drugs concerning either active compound or total content was developed. The examined dosage forms consisted of 10 injectable ampoules and 10 bottles of oral solutions. The irradiation of samples and standards was carried out in the rotation system of the Reactor of Nuclear Research Center Democritos with maximal neutron flux of 2,9.1013 n.cm-2.sec-1. Gamma-ray spectrometry of the irradiated samples and standards was accomplished with a coaxial Ge(Li) detector series Win 15 with an efficiency of 15% connected to an Ino-Tech 1024 channel analyser (Model IT 5200). The accuracy and precision of the method are found to be very high and therefore it could be established as an official one for the determination of sodium in parmaceuticals

  12. Analysis of medicinal plant extracts by neutron activation method

    International Nuclear Information System (INIS)

    This dissertation has presented the results from analysis of medicinal plant extracts using neutron activation method. Instrumental neutron activation analysis was applied to the determination of the elements Al, Br, Ca, Ce, Cl, Cr, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sb, Sc and Zn in medicinal extracts obtained from Achyrolcline satureoides DC, Casearia sylvestris, Centella asiatica, Citrus aurantium L., Solano lycocarpum, Solidago microglossa, Stryphnondedron barbatiman and Zingiber officinale R. plants. The elements Hg and Se were determined using radiochemical separation by means of retention of Se in HMD inorganic exchanger and solvent extraction of Hg by bismuth diethyl-dithiocarbamate solution. Precision and accuracy of the results have been evaluated by analysing reference materials. The therapeutic action of some elements found in plant extracts analyzed was briefly discussed

  13. Nondestructive multielementary analysis of human hair by neutron activation

    International Nuclear Information System (INIS)

    Various elements contained in human hair have been used for an index of environmental pollution effect of human body. Nondestructive neutron activation analysis was applied to hair samples on 61 inhabitants of a local district which was free from air pollution. At Rikkyo University hair samples were irradiated for 3 minutes or 15 hours (5 hours/day, 3 days) in a TRIGA Mark II Reactor with a neutron flux of 1.5x1012 n/cm2/sec. The activities were measured by a Ge(Li) detector. 18 elements could be determined: Al, Br, Ca, Cl, Cu, I, Mg, Mn, Na, S and V with the 3 minute irradiation method, and As, Au, Cr, K, La, Sb and Zn with the 15 hour irradiation method. Concentration-distribution histograms, and differences in distribution patterns of these elements caused by permanent wave treatment, sex or age were discussed. (auth.)

  14. Gamma-neutron activation experiments using laser wakefield accelerators

    International Nuclear Information System (INIS)

    Gamma-neutron activation experiments have been performed with relativistic electron beams produced by a laser wakefield accelerator. The electron beams were produced by tightly focusing (spot diameter ≅6 μm) a high power (up to 10 TW), ultra-short (≥50 fs) laser beam from a high repetition rate (10 Hz) Ti:sapphire (0.8 μm) laser system, onto a high density (>1019 cm-3) pulsed gasjet of length ≅1.5 mm. Nuclear activation measurements in lead and copper targets indicate the production of electrons with energy in excess of 25 MeV. This result was confirmed by electron distribution measurements using a bending magnet spectrometer. Measured γ-ray and neutron yields are also found to be in reasonable agreement with simulations using a Monte Carlo transport code

  15. Prompt gamma-ray neutron activation analysis of boron using Deuterium-Deuterium (D-D) neutron generator

    International Nuclear Information System (INIS)

    Prompt gamma-ray neutron activation analysis (PGNAA) is a nuclear analytical technique for the determination of trace and other elements in solid, liquid or gaseous samples. The method consists in observing gamma rays emitted by a sample during neutron irradiation. The PGNAA system was built using a moderated and shielded deuterium-deuterium (D-D) neutron generator. This facility has been developed to determine the chemical composition of materials. The neutron generator is composed of three major components: An RF-Induction Ion Source, the Secondary Electron Shroud, and the Diode Accelerator Structure and Target. The generator produces monoenergetic neutrons (2.5 MeV) with a yield of 1010 n/s using 25-50 mA of beam current and 125 kV of acceleration voltage. Prompt γ-ray neutron activation analysis of 10B concentrations in Si and SiO2 matrices was carried out using a germanium detector (HPGe) and the results obtained are compared with a PGNAA system using a NaI detector. Neutron flux and energy distribution from D-D neutron generator at the sample position was calculated using Monte Carlo simulation. The interaction properties of neutrons in a Germanium detector have been studied. (author)

  16. Pinus roxburghii plant needles as a three-season biomonitor for elemental air pollution monitoring along roadside

    International Nuclear Information System (INIS)

    The present study deals with the determination of 36 elements in Pinus roxburghii plant needles to assess their potential as biomonitor for elemental air pollution monitoring. The elemental quantification was made by employing Instrumental Neutron Activation Analysis (INAA) and Atomic Absorption Spectrometric (AAS) techniques. The needles of Pinus roxburghii were collected in spring, summer and winter seasons from various sites in Islamabad. The method validation was performed by analyzing two certified reference materials i.e., Citrus leaves - NIST-SRM-1572 and IAEA-Soil-7. Pollution level was assessed by using three indicators: enrichment factor, pollution load index and average toxic element concentration. The results indicated that the needles of Pinus roxburghii plant had potential to monitor the extent of air pollution in the vicinity of high traffic areas.

  17. Neutron activation measurements in research reactor concrete shield

    International Nuclear Information System (INIS)

    The results of activation measurement inside TRIGA research reactor concrete shielding are given. Samples made of ordinary and barytes concrete together with gold and nickel foils were irradiated in the reactor body. Long-lived neutron-induced gamma-ray-emitting radioactive nuclides in the samples were measured with HPGe detector. The most active longlived radioactive nuclides in ordinary concrete samples were found to be 60Co and 152Eu and in barytes concrete samples 60Co, 152Eu and 133Ba. Measured activity density of all nuclides was found to decrease almost linearly with depth in logarithmic scale.(author)

  18. Aerosol and air pollution study by neutron activation analysis

    International Nuclear Information System (INIS)

    Thermal neutron activation analysis technique was used in air pollution and aerosol elemental content and size distribution investigations. Air pollution samples were collected on Whatman 41 paper filters which were activated along with known quantities of standards in a flux of approximately 1013 nxcm-2xs-1. The activity of the samples was measured with a 40 cm3 Ge(Li) detector and analyzed with the computer program JANE, which identified the isotopes and found their quantities by normalization with the standard measurement results. Correlation between the various elements, in particular those belonging to dust from the desert and those considered typical urban air pollution, is investigated. (author)

  19. Protein determination in soya bean by fast neutron activation analysis

    International Nuclear Information System (INIS)

    For a non-destructive determination of the protein content in soya bean samples, 14-MeV neutron activation analysis was applied. To check the method, the results obtained by X-ray fluorescence analysis and the Kjeldahl procedure were compared. For pressed pellet samples of about 1 g with 15 min irradiation and 10 min measuring times the accuracy of the protein determination was found to be 15%. (author) 7 refs.; 4 figs.; 3 tabs

  20. Aspects of precision and accuracy in neutron activation analysis

    International Nuclear Information System (INIS)

    Analytical results without systematic errors and with accurately known random errors are normally distributed around their true values. Such results may be produced by means of neutron activation analysis both with and without radiochemical separation. When all sources of random variation are known a priori, their effect may be combined with the Poisson statistics characteristic of the counting process, and the standard deviation of a single analytical result may be estimated. The various steps of a complete neutron activation analytical procedure are therefore studied in detail with respect to determining their contribution to the overall variability of the final result. Verification of the estimated standard deviation is carried out by demonstrating the absence of significant unknown random errors through analysing, in replicate, samples covering the range of concentrations and matrices anticipated in actual use. Agreement between the estimated and the observed variability of replicate results is then tested by a simple statistic T based on the chi-square distribution. It is found that results from neutron activation analysis on biological samples can be brought into statistical control. In routine application of methods in statistical control the same statistical test may be used for quality control when some of the actual samples are analysed in duplicate. This analysis of precision serves to detect unknown or unexpected sources of variation of the analytical results, and both random and systematic errors have been discovered in practical trace element investigations in different areas of research. Particularly, at the ultratrace level of concentration where there are few or no standard reference materials for ascertaining the accuracy of results, the proposed quality control based on the analysis of precision combined with neutron activation analysis with radiochemical separation, with an a priori precision independent of the level of concentration, becomes a

  1. Neutron activation analysis in the investigation of pseudomonas to mercury

    International Nuclear Information System (INIS)

    The aim of this work was to investigate the resistance to mercury in Pseudomonas. The measurements were performed by using neutron activation technique. The TRIGA MARK 1-IPE-R1 reactor was used as the irradiation facility, and the nuclide Hg202 as target element. The experimental results showed that cultures of Pseudomonas during the logarithmic growing phase, have a significant volatilization of the Hg, while during the stationary phase, they absorb and retain this metal. (author)

  2. Multielement determination in soil extracts by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Forest Swiss soils from 39 locations, each sampled at three depths, were extracted with a buffered solution of pH 4.65 containing EDTA. Nearly 30 elements were determined by instrumental neutron activation analysis. The results obtained are discussed in terms of efficiency of the extractant, precision and accuracy. Summarized results are presented for the quantity fractions of the extracted elements. (author) 18 refs.; 4 figs.; 3 tabs

  3. Activation analysis utilizing fast radiochemical separations and portable neutron generators

    International Nuclear Information System (INIS)

    Experience at the University of Michigan in adapting radiochemical procedures to short-half-lived radioisotopes and in working with neutron generators indicates that activation analysis can become a rapid routine industrial method for certain types of analysis. Portable neutron generators with thermal fluxes approaching 108 to 109 n/cm2 s, which have recently become available, offer the large analytical laboratory its own source of neutrons for activation analysis at a cost of about $ 20 000. In addition, rapid radiochemical procedures permit separation of activated products in a matter of minutes and completion of analyses for many elements in less than an hour. Rapid radiochemical separations have been devised for several elements. The sensitivities obtained from a 6-min irradiation of these elements are at least of the same order of magnitude and often better than those obtained with lengthy irradiations. Typical separation times are for vanadium 4 min and for silver 5 min. Thus it has been possible to make a complete analysis of samples ranging from meteorites to rat liver tissue, from marine biological ashes to crude petroleum, all within periods of 1/2 h to 1 h. These fast radiochemical techniques are also being applied to an evaluation of a Texas Nuclear Corporation neutron generator for use in activation analysis. This Cockcroft-Walton machine is small and compact; portable concrete shielding blocks suffice for protection. Although the present flux obtainable is less than 0.1% of the flux available in the pneumatic tube positions of the Michigan reactor, it is still sufficient to determine microgram amounts of an element such as vanadium. (author)

  4. Gold determination in massive samples by neutron activation analysis

    CERN Document Server

    Broglio, Eduardo

    2015-01-01

    This work presents the characteristics of the Neutron Activation Analysis (NAA) in the determination of gold in voluminous mineral samples using a linear particle accelerator (Linac) as source of irradiation. The used volumes are one or two orders of magnitude higher than the ones that can be used in nuclear research reactor, which is the source usually used to determine through the NAA. This study was encouraged by a specific legal requirement to determine the gold law in a small Patagonian gold deposit.

  5. Neutron activation analysis of copper, zinc and manganese in plants

    International Nuclear Information System (INIS)

    A fast method for simultaneous quantitative determination of microscopic quantities of copper, zinc and manganese in plant tissue through neutron activation analysis is suggested. The measurements are carried out after removal of the 24Na and 42K interference. Optimum conditions for detention of the microscopic quantities of Cu, Zn and Mn by the chelating resin Chelex-100 using the batch procedure are determined. (author)

  6. Neutron activation analysis of cheese, eggs, fish, fowl and meats

    International Nuclear Information System (INIS)

    The concentrations of Br, Ca, Cl, Cu, I, K, Mg, Na, Rb, S and Ti in 44 samples of cheese, eggs, fish, fowl and meats sold in Canada were determined with absolute instrumental neutron activation analysis. The procedure is fully computerized and incorporates one short irradiation and counting only. When an element was not detected, its detection limit was calculated. The nuclear interferences and blanks were taken into account. The nutritional significance of the results is discussed. (author)

  7. Biomonitoring with Wireless Communications

    Energy Technology Data Exchange (ETDEWEB)

    Budinger, Thomas F.

    2003-03-01

    This review is divided into three sections: technologies for monitoring physiological parameters; biosensors for chemical assays and wireless communications technologies including image transmissions. Applications range from monitoring high risk patients for heart, respiratory activity and falls to sensing levels of physical activity in military, rescue, and sports personnel. The range of measurements include, heart rate, pulse wave form, respiratory rate, blood oxygen, tissue pCO2, exhaled carbon dioxide and physical activity. Other feasible measurements will employ miniature chemical laboratories on silicon or plastic chips. The measurements can be extended to clinical chemical assays ranging from common blood assays to protein or specialized protein measurements (e.g., troponin, creatine, and cytokines such as TNF and IL6). Though the feasibility of using wireless technology to communicate vital signs has been demonstrated 32 years ago (1) it has been only recently that practical and portable devices and communications net works have become generally available for inexpensive deployment of comfortable and affordable devices and systems.

  8. A Brief overview of neutron activation analyses methodology and applications

    International Nuclear Information System (INIS)

    The primary objective of this talk is to present our new facility for Neutron Activation Analysis to the scientific and industrial societies and show its possibilities. Therefore my talk will handle the following main items: An overview of neutron activation analysis, The special interest of fast mono-energetic neutrons, The NAA method and its sensitivities, The Recent scientific and industrial applications using NAA, and o An illustrating example measured by using our facility is presented What is NAA? It is a sensitive analytical technique useful for performing both qualitative and quantitative multi-element analyses in samples. Worldwide application of NAA is so widespread; it is estimated that approximately several 10,000 samples undergo analysis each year from almost every conceivable field of scientific or technical interest. Why NAA? For many elements and applications, NAA: Offers sensitivities that are sometimes superior to those attainable by other methods, on the order of nano-gram level, It is accurate and reliable, NAA is generally recognized as the referee methodof choice when new procedures are being developed or when other methods yield results that do not agree. However, the activation analysis at En=14 MeV is limited by a few factors: Low value of flux, low cross-sections of threshold reactions, o Short irradiation time due to finite target life, Interfering reactions and gamma ray spectral interference

  9. Prompt gamma neutron activation analysis as an active interrogation technique for nuclear materials

    International Nuclear Information System (INIS)

    Prompt gamma neutron activation analysis (PGAA) is proposed as an instant, non-destructive method for the analysis of fissile materials and fission products. Measurements by PGAA were made on technetium and uranium compounds, the latter with various enrichments. Measurements were carried out in thermal and cold neutron beams at the Budapest Research Reactor. A beam chopper was used to collect the delayed decay gamma radiation from short lived nuclides separately. Accurate partial gamma ray production cross-sections were determined with internal standardization for a set of prompt and decay gamma rays following neutron capture in 235U, 238U and 99Tc and compared to those from the literature. In the case of 235U fission, prompt gamma lines were also applied.These cross-sections can be used for non-destructive analyses of uranium and technetium and also for the determination of the enrichment of uranium by prompt gamma activation analysis and neutron activation analysis. (author)

  10. Manila clam Venerupis philippinarum as a biomonitor to metal pollution

    Science.gov (United States)

    Wu, Huifeng; Ji, Chenglong; Wang, Qing; Liu, Xiaoli; Zhao, Jianmin; Feng, Jianghua

    2013-01-01

    The Manila clam Venerupis philippinarum is a good biomonitor/bioindicator to marine metal pollution and is frequently used in aquatic toxicology. Two dominant pedigrees (white and zebra) of clam are distributed in the Bohai Sea; however, little attention has been paid to potential biological differences between these two pedigrees. In this study, we tested the sensitivity of both pedigrees to marine metal (cadmium and zinc) pollution biomonitoring and marine environmental toxicology. Results demonstrate significant biological differences in gills of white and zebra clams based on metabolic profiles and antioxidant enzyme activities. In addition, we found that hypotaurine, malonate and homarine were relatively high in white clam gills, while alanine, arginine, glutamate, succinate, 4-aminobutyrate, taurine and betaine were high in zebra clam gills. Zebra clam gills were also more sensitive to a mixture of Cd and Zn, as shown by antioxidant enzyme activities and metabolic profiles, but white clam gills could accumulate more Zn. Therefore, we suggest that the white pedigree can be used as a biomonitor to marine Zn pollution, whereas the zebra pedigree can be used for toxicology studies on Cd and Zn mixed pollution.

  11. Manila clam Venerupis philippinarum as a biomonitor to metal pollution

    Institute of Scientific and Technical Information of China (English)

    WU Huifeng; JI Chenglong; WANG Qing; LIU Xiaoli; ZHAO Jianmin; FENG Jianghua

    2013-01-01

    The Manila clam Venerupis philippinarum is a good biomonitor/bioindicator to marine metal pollution and is frequently used in aquatic toxicology.Two dominant pedigrees (white and zebra) of clam are distributed in the Bohai Sea; however,little attention has been paid to potential biological differences between these two pedigrees.In this study,we tested the sensitivity of both pedigrees to marine metal (cadmium and zinc) pollution biomonitoring and marine environmental toxicology.Results demonstrate significant biological differences in gills of white and zebra clams based on metabolic profiles and antioxidant enzyme activities.In addition,we found that hypotaurine,malonate and homarine were relatively high in white clam gills,while alanine,arginine,glutamate,succinate,4-aminobutyrate,taurine and betaine were high in zebra clam gills.Zebra clam gills were also more sensitive to a mixture of Cd and Zn,as shown by antioxidant enzyme activities and metabolic profiles,but white clam gills could accumulate more Zn.Therefore,we suggest that the white pedigree can be used as a biomonitor to marine Zn pollution,whereas the zebra pedigree can be used for toxicology studies on Cd and Zn mixed pollution.

  12. Fusion material transmutation and activation analysis induced by fast neutrons: Anita-IEAF Activation Code Package

    International Nuclear Information System (INIS)

    This paper presents the Anita-IEAF code package for the activation characterization of materials exposed to neutrons with energies above 20 MeV. Its origins trace back to the Anita-2000 code (NEA-1638, RSICC CCC-606). Anita-IEAF is able to manage the many reaction channels for neutron energies up to 150 MeV. It computes the radioactive inventories of materials exposed to neutron irradiation, continuously or stepwise. It provides activity, isotopic nuclide density, decay heat, biological hazard, clearance index and gamma ray source spectra at shutdown and at different cooling times. The code package is provided with a complete database that includes neutron activation data library, decay, hazard and clearance data library, and gamma library. The Anita-IEAF neutron activation library was produced by processing the IEAF-2001 data activation files that have been recently released by FZK. It contains the neutron activation cross-sections for 679 nuclides in the 256 neutron energy group structure up to 150 MeV, in EAF format. That group structure includes the standard Vitamin-J 175 groups for energies below 20 MeV and 81 groups for the highest energies. The paper presents also an application of the Anita-IEAF code package to the neutron exposure characterization for the SS-316 liner and heat shield of the Test Cell area of the International Fusion Materials Irradiation Facility (IFMIF). The decay gamma source evaluation for SS-316, needed for dose rate calculations at beam-off IFMIF phase for shielding analysis, is discussed too. (authors)

  13. Provenience studies using neutron activation analysis: the role of standardization

    International Nuclear Information System (INIS)

    This paper covers the historical background of chemical analysis of archaeological artifacts which dates back to 1790 to the first application of neutron activation analysis to archaeological ceramics and goes on to elaborate on the present day status of neutron activation analysis in provenience studies, and the role of standardization. In principle, the concentrations of elements in a neutron-activated specimen can be calculated from an exact knowledge of neutron flux, its intensity, duration and spectral (energy) distribution, plus an exact gamma ray count calibrated for efficiency, corrected for branching rates, etc. However, in practice it is far easier to compare one's unknown to a standard of known or assumed composition. The practice has been for different laboratories to use different standards. With analyses being run in the thousands throughout the world, a great benefit would be derived if analyses could be exchanged among all users and/or generators of data. The emphasis of this paper is on interlaboratory comparability of ceramic data; how far are we from it, what has been proposed in the past to achieve this goal, and what is being proposed. All of this may be summarized under the general heading of Analytical Quality Control - i.e., how to achieve precise and accurate analysis. The author proposes that anyone wishing to analyze archaeological ceramics should simply use his own standard, but attempt to calibrate that standard as nearly as possible to absolute (i.e., accurate) concentration values. The relationship of Analytical Quality Control to provenience location is also examined

  14. Mercury mass measurement in fluorescent lamps via neutron activation analysis

    Science.gov (United States)

    Viererbl, L.; Vinš, M.; Lahodová, Z.; Fuksa, A.; Kučera, J.; Koleška, M.; Voljanskij, A.

    2015-11-01

    Mercury is an essential component of fluorescent lamps. Not all fluorescent lamps are recycled, resulting in contamination of the environment with toxic mercury, making measurement of the mercury mass used in fluorescent lamps important. Mercury mass measurement of lamps via instrumental neutron activation analysis (NAA) was tested under various conditions in the LVR-15 research reactor. Fluorescent lamps were irradiated in different positions in vertical irradiation channels and a horizontal channel in neutron fields with total fluence rates from 3×108 cm-2 s-1 to 1014 cm-2 s-1. The 202Hg(n,γ)203Hg nuclear reaction was used for mercury mass evaluation. Activities of 203Hg and others induced radionuclides were measured via gamma spectrometry with an HPGe detector at various times after irradiation. Standards containing an Hg2Cl2 compound were used to determine mercury mass. Problems arise from the presence of elements with a large effective cross section in luminescent material (europium, antimony and gadolinium) and glass (boron). The paper describes optimization of the NAA procedure in the LVR-15 research reactor with particular attention to influence of neutron self-absorption in fluorescent lamps.

  15. Analysis of Protein in Soybean by Neutron Activation Technique

    International Nuclear Information System (INIS)

    Nitrogen content in soybean was studied by using Neutron Activation Analysis technique through fast neutron at the flux of 2.5 * 1011 n/cm2. sec in the CA-3 out-core irradiation tube of the Thai Research Reactor-1/Modification 1 (TRR-1/M1, Triga Mark 3 type). By measuring gamma ray of 511 keV from 13N of the nuclear reaction, 14N(n, 2n)13N caused by the annihilation of positron disintegrated, the semi-conductor detector (HPGe) was connected with the multi-channel analyzer (MCA) and monitor to display the spectrum range. NH4NO3 was used as the standard for the analysis. The inaccuracy of the analysis caused by other radioisotopes, i.e. potassium, phosphorus and reaction from recoiled proton scattering in soybean was corrected. The data of 27 samples analyzed by neutron activation showed no significant difference in the nitrogen content. The average nitrogen content of all the soybean samples is 7.02% equivalent to protein content of 43.88%

  16. Speciation neutron activation analysis for arsenic in marine fish

    International Nuclear Information System (INIS)

    Neutron activation analysis (NAA) methods involving chemical separations prior to irradiations can be developed to determine the species of an element. The technique can be called speciation NAA (SNAA). We have developed SNAA methods for assaying various arsenic species, namely As(III), As(V), dimethyl arsonic acid (DMA), monomethylarsinic acid (MMA), arsenobetaine (AsB), organically bound arsenic (OBAs), and lipid-soluble arsenic (LSAs) in marine fish samples. The method involves extraction by a methanol-MIBK-water system, cation exchange chromatography, and HPLC followed by NAA. The detection limits for various arsenic species are around 20 ng g-1 of fish under the experimental conditions of 2-h irradiation in a neutron flux of 5x1011 cm-2 s-1 at the Dalhousie University SLOWPOKE-2 facility. Details of the methods and results are presented

  17. Neutron activation determination of impurities in molybdenite and galena

    International Nuclear Information System (INIS)

    A method is described for non-destructive neutron-activation determination of 14 chemical elements (Na, Ag, Zn, Sc, La, Eu, Tb, Yb, Sb, Ta, Gr, Se, Fe and Co) in molybdenite and galenite minerals. The samples and standards of Ag, Se, Co and Np have been wrapped in an aluminium foil and packed in an aluminium container; they have been then irradiated for 10 hr in the vertical channel of a nuclear reactor with flux of thermal neutrons (3.0, 0.45)x1013 n/cm2xsec to record the γ-spectra of the samples and standards 1, 5, 16, 65, 265 and 350 days after irradiation on a γ-spectrometer with a Ge(Li)-detector. The results are found to be in a good agreement with the spectra of Ag, Sb, La and Fe

  18. The Application of Neutron Activation Analysis in Thailand

    International Nuclear Information System (INIS)

    The technique of neutron activation analysis was introduced at the OAEP about 5 years ago. Since that time, it has become a useful technique for the determination. in particular, of certain trace inorganic elements in biological samples in this country. Scientists here have been working in close co-operation with those in other Government laboratories to meet the requirements of their studies. At present, a high resolution solid state gamma-ray detector is lacking in our laboratory. The results of the work to be described briefly were thus mainly carried out utilising our research reactor as the neutron source and multi-channel analysers together with the technique of radiochemical separation. In some cases, the non-destructive method was found feasible

  19. Neutron activation analysis of gold in teak (tectona grandis)

    International Nuclear Information System (INIS)

    The amount of gold in teak had been determined by using neutron activation technique. The neutron flux utilized was of the order of 1010n/cm2/sec. As usual the spectrum of the energy peak of gold was identified using a gamma-multichannel pulse height analyzer. The sensitivity for gold was approximately 10-7g. In teak especially Na, As, Cu, Mn and La were interfering elements in the energy region of 0.4-0.8 MeV. With the result, the non-destructive analysis only was not possible and radiochemical separation was found essential. The gold content of teak was 0.58+0.0037 ppm

  20. Activation analysis using cyclotron-produced fast neutrons

    International Nuclear Information System (INIS)

    The possibilities of activation analysis by using cyclotron-produced fast neutrons are investigated for more than 30 chemical elements. The angular distributions of fast neutrons produced by bombarding a thick beryllium target with 11.5 MeV protons, 3 and 6 MeV deuterons were obtained for five angles in the forward hemisphere. The yield's of the radionuclides produced by nuclear reactions (n,p), (n,α), (n,γ), (n,n,γ) were measured or calculated. It is showed that the yields of the majority of radionuclides are within 103-105 Bk.(μA.h.g)1. These data were used for the evaluation of the limit detection of chemical elements. The values of the LD are equal to 0.1-1 μg for some elements, whereas for majority elements they are l-100 μg

  1. Neutron shielding and activation of the MASTU device and surrounds

    CERN Document Server

    Taylor, David; Turner, Andrew; Davis, Andrew

    2014-01-01

    A significant functional upgrade is planned for the Mega Ampere Spherical Tokamak (MAST) device, located at Culham in the UK, including the implementation of a notably greater neutral beam injection power. This upgrade will cause the emission of a substantially increased intensity of neutron radiation for a substantially increased amount of time upon operation of the device. Existing shielding and activation precautions are shown to prove insufficient in some regards, and recommendations for improvements are made, including the following areas: shielding doors to MAST shielded facility enclosure (known as "the blockhouse"); north access tunnel; blockhouse roof; west cabling duct. In addition, some specific neutronic dose rate questions are addressed and answered; those discussed here relate to shielding penetrations and dose rate reflected from the air above the device ("skyshine").

  2. Prompt gamma activation analysis using mobile reactor neutron beam

    International Nuclear Information System (INIS)

    Among the nuclear analytical methods that have proved very useful in biological and medical analyses is the in vivo prompt gamma neutron activation analysis (IVPGAA). In this work, an IVPGAA facility was assembled on a zero-power mobile nuclear reactor and has demonstrated its versatility for in vivo medical diagnosis. Absolute measurements of some environmental contaminants such as Cd, Hg, and Si in organs can be determined rapidly by partial body scan of IVPGAA, while assessment of vital constituents such as Ca, Cl, N, and P in either whole body or body part can be scanned by IVPGAA technique effectively. The in vivo clinical application using mobile reactor neutron beam are reviewed in detail. The IVPGAA scan provides unique insight into elemental concentration purpose. The IVPGAA scan can be performed on a regular basis without discomfort and radiation risk for patients. (author)

  3. Determination of mercury in food by neutron activation

    International Nuclear Information System (INIS)

    Determination of mercury in food samples has been carried out by neutron activation followed by chemical separation to remove the interfering activities of copper, zinc etc. Chemical separation was carried out using anion exchange resin (DOWEX 1x8). Mercury was determined by counting 77 keV γ-rays of 197Hg on a NaI(Tl) crystal in conjunction with a 400-channel pulse-height analyser. Levels of mercury in the following foods are tabulated: rice, wheat, pulses, millets, leafy vegetables, flower, carrot, potato, tomato, onion, chilli powder, sugar, tea leaves, milk. (T.I.)

  4. Non-destructive plant-nutrition analysis by neutron analysis by neutron activation and X-ray fluorescence techniques

    International Nuclear Information System (INIS)

    Non-destructive neutron activation and x-ray fluorescence techniques have been applied to the analysis of plant nutrients in soil. The advantages of these methods over the conventional ones have also been focussed. (author)

  5. Diagnosis of mucoviscidosis by neutron activation analysis. Part 1; Diagnostico da mucoviscidose utilizando analise por ativacao com neutrons. Parte 1

    Energy Technology Data Exchange (ETDEWEB)

    Bellido, Luis F.; Bellido, Alfredo V

    1997-02-01

    Symptoms pathology, incidence, and gravity of the inherent syndrome called mucoviscidosis, or cystic fibrosis are described in this Part I. The analytical methods used for its diagnosis, both the conventional chemical ones and by neutron activation analysis are also summarised. Finally, an analytical method to study the incidence of mucoviscidosis in Brazil is presented. This , essentially, consists in bromine determination, in fingernails, by resonance neutron activation analysis. (author) 33 refs., 13 figs.

  6. A militarily fielded thermal neutron activation sensor for landmine detection

    Energy Technology Data Exchange (ETDEWEB)

    Clifford, E.T.H. [Bubble Technology Industries, Chalk River (Canada); McFee, J.E. [Defence R and D Canada-Suffield, Medicine Hat (Canada)], E-mail: john.mcfee@drdc-rddc.gc.ca; Ing, H.; Andrews, H.R.; Tennant, D.; Harper, E. [Bubble Technology Industries, Chalk River (Canada); Faust, A.A. [Defence R and D Canada-Suffield, Medicine Hat (Canada)

    2007-08-21

    The Canadian Department of National Defence has developed a teleoperated, vehicle-mounted, multi-sensor system to detect anti-tank landmines on roads and tracks in peacekeeping operations. A key part of the system is a thermal neutron activation (TNA) sensor which is placed above a suspect location to within a 30 cm radius and confirms the presence of explosives via detection of the 10.835 MeV gamma ray associated with thermal neutron capture on {sup 14}N. The TNA uses a 100{mu}g{sup 252}Cf neutron source surrounded by four 7.62cmx7.62cm NaI(Tl) detectors. The system, consisting of the TNA sensor head, including source, detectors and shielding, the high-rate, fast pulse processing electronics and the data processing methodology are described. Results of experiments to characterize detection performance are also described. The experiments have shown that anti-tank mines buried 10 cm or less can be detected in roughly a minute or less, but deeper mines and mines significantly displaced horizontally take considerably longer time. Mines as deep as 30 cm can be detected for long count times (1000 s). Four TNA detectors are now in service with the Canadian Forces as part of the four multi-sensor systems, making it the first militarily fielded TNA sensor and the first militarily fielded confirmation sensor for landmines. The ability to function well in adverse climatic conditions has been demonstrated, both in trials and operations.

  7. Coincidence Prompt Gamma-Ray Neutron Activation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    R.P. gandner; C.W. Mayo; W.A. Metwally; W. Zhang; W. Guo; A. Shehata

    2002-11-10

    The normal prompt gamma-ray neutron activation analysis for either bulk or small beam samples inherently has a small signal-to-noise (S/N) ratio due primarily to the neutron source being present while the sample signal is being obtained. Coincidence counting offers the possibility of greatly reducing or eliminating the noise generated by the neutron source. The present report presents our results to date on implementing the coincidence counting PGNAA approach. We conclude that coincidence PGNAA yields: (1) a larger signal-to-noise (S/N) ratio, (2) more information (and therefore better accuracy) from essentially the same experiment when sophisticated coincidence electronics are used that can yield singles and coincidences simultaneously, and (3) a reduced (one or two orders of magnitude) signal from essentially the same experiment. In future work we will concentrate on: (1) modifying the existing CEARPGS Monte Carlo code to incorporate coincidence counting, (2) obtaining coincidence schemes for 18 or 20 of the common elements in coal and cement, and (3) optimizing the design of a PGNAA coincidence system for the bulk analysis of coal.

  8. RADSAT Benchmarks for Prompt Gamma Neutron Activation Analysis Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Burns, Kimberly A.; Gesh, Christopher J.

    2011-07-01

    The accurate and efficient simulation of coupled neutron-photon problems is necessary for several important radiation detection applications. Examples include the detection of nuclear threats concealed in cargo containers and prompt gamma neutron activation analysis for nondestructive determination of elemental composition of unknown samples. High-resolution gamma-ray spectrometers are used in these applications to measure the spectrum of the emitted photon flux, which consists of both continuum and characteristic gamma rays with discrete energies. Monte Carlo transport is the most commonly used simulation tool for this type of problem, but computational times can be prohibitively long. This work explores the use of multi-group deterministic methods for the simulation of coupled neutron-photon problems. The main purpose of this work is to benchmark several problems modeled with RADSAT and MCNP to experimental data. Additionally, the cross section libraries for RADSAT are updated to include ENDF/B-VII cross sections. Preliminary findings show promising results when compared to MCNP and experimental data, but also areas where additional inquiry and testing are needed. The potential benefits and shortcomings of the multi-group-based approach are discussed in terms of accuracy and computational efficiency.

  9. Characterization of hydrogen in concrete by cold neutron prompt gamma-ray activation analysis and neutron incoherent scattering

    Energy Technology Data Exchange (ETDEWEB)

    Paul, R.L.; Chen-Mayer, H.H.; Lindstrom, R.M.; Blaauw, M.

    2000-07-01

    A combination of cold neutron prompt gamma-ray activation analysis (PGAA) and neutron incoherent scattering (NIS) has been used for nondestructive characterization of hydrogen as a function of position in slabs of wet concrete of different composition. Hydrogen was determined by PGAA by scanning each sample across of 5 mm diameter neutron beam in 10 mm increments, and measuring the 2223 keV prompt gamma ray. NIS measurements were performed by scanning the samples across a 5 mm diameter neutron beam at 5 mm increments and detecting scattered neutrons. The measurements demonstrate the feasibility of the techniques for 2D compositional mapping of hydrogen and other elements in materials, and indicate the potential of these methods for monitoring the uniformity of drying concrete.

  10. Archaeometry Applications of Cold Neutron Based Prompt Gamma Neutron Activation Analysis. Chapter 9

    International Nuclear Information System (INIS)

    Prompt gamma activation analysis (PGAA) is based on the detection of prompt gamma radiation following the capture of neutrons into the atomic nucleus. Since every atomic nucleus emits characteristic prompt gamma radiation, this method is suitable for multielemental (panorama) analysis. The PGAA method can be regarded as absolutely non-destructive, because of the relatively low intensity of the beam. The main focus of this project was on the research of ancient ceramics. Pottery production was one of the most important crafts of prehistoric communities. As the first aim of this project, pottery findings from Neolithic and later prehistoric sites in Hungary were investigated with PGAA. Compositions of local sediments, as potential raw material sources, were compared with those of pottery. As the second aim of the project, pottery fragments from the multiperiod site at Voers, in south-west Hungary, were analysed, together with clay from the surrounding areas. In a firing experiment, an attempt to reproduce the ancient production techniques was made. As a third aim of the project, PGAA was tested from a methodological point of view. The reliability of the method has been occasionally checked through parallel measurements of archaeological samples with instrumental neutron activation analysis and X ray fluorescence analysis as well. The authors took part in a proficiency test, organized by the IAEA, on a porcelain material. (author)

  11. Neutron distribution and induced activity inside a Linac treatment room.

    Science.gov (United States)

    Juste, B; Miró, R; Verdú, G; Díez, S; Campayo, J M

    2015-08-01

    Induced radioactivity and photoneutron contamination inside a radiation therapy bunker of a medical linear accelerator (Linac) is investigated in this work. The Linac studied is an Elekta Precise electron accelerator which maximum treatment photon energy is 15 MeV. This energy exceeds the photonuclear reaction threshold (around 7 MeV for high atomic number metals). The Monte Carlo code MCNP6 has been used for quantifying the neutron contamination inside the treatment room for different gantry rotation configuration. Walls activation processes have also been simulated. The approach described in this paper is useful to prevent the overexposure of patients and medical staff. PMID:26737878

  12. Neutron Activation Analysis of Pre-Columbian Pottery in Venezuela

    International Nuclear Information System (INIS)

    Pre-Hispanic pottery figurines from north-central Venezuela islands and mainland were analysed by neutron activation analysis (INAA and PGAA) at the Budapest Research to establish their provenience. In order to classify the samples of figurines, characteristic molecular and atomic components were determined. Several mass ratios were calculated for significant classification of the object of two origins. Results shed light on the origin of island figurines and suggest specific areas of their production on the mainland, contributing to better understanding of late pre-Hispanic migration patterns in the southeastern Caribbean region

  13. Characterization of the volcanic eruption emissions using neutron activation analysis

    International Nuclear Information System (INIS)

    Characterization of the volcanic particulate material has been performed by analyzing aerosols and ashes with instrumental neutron activation analysis. Crustal enrichment factors were calculated using the elemental concentration and clustering techniques, and multivariate analysis were done. The analytical and data treatment methodologies allowed the sample differentiation from their geographical origin viewpoint, based on their chemical composition patterns, which are related to the deposit formation processes, which consist of direct deposition from the volcanic cloud, and removal by wind action after the end of the eruption, and and finally the deposition. (author). 8 refs., 5 figs

  14. Control of pneumatic transfer system for neutron activation analysis

    International Nuclear Information System (INIS)

    Pneumatic transfer system(PTS) is one of the facilities to be used in irradiation of target materials for neutron activation analysis(NAA) in the research reactor. There are two systems the manual and the automatic system in PTS of HANARO research reactor. The pneumatic transfer system consists of many devices, sends and loads the capsules from NAA laboratory into three holes in the reflector tank of reactor and retrieves irradiated capsules after irradiation. This report describes the part's design, control system and the operation procedures. All the algorithm described in the text will be used for maintenance and upgrading

  15. Control of pneumatic transfer system for neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jung, H. S.; Chung, Y. S.; Wu, J. S.; Kim, H. K.; Choi, Y. S.; Kim, S. H.; Moon, J. H.; Baek, S. Y

    2000-06-01

    Pneumatic transfer system(PTS) is one of the facilities to be used in irradiation of target materials for neutron activation analysis(NAA) in the research reactor. There are two systems the manual and the automatic system in PTS of HANARO research reactor. The pneumatic transfer system consists of many devices, sends and loads the capsules from NAA laboratory into three holes in the reflector tank of reactor and retrieves irradiated capsules after irradiation. This report describes the part's design, control system and the operation procedures. All the algorithm described in the text will be used for maintenance and upgrading.

  16. Multielement analysis of iliac crest bone by neutron activation

    International Nuclear Information System (INIS)

    Bone samples from iliac crest were obtained from apparently healthy female (n = 4) and male (n = 8) subjects with ages between 15-50. Cortical and trabecular parts were separated and soft tissues like fat, muscle and blood were removed. Calcium, Mg, Na, Cl, Fe, Zn, Br, Sr, and Cs were determined by instrumental neutron activation analysis and other techniques, and their relations were discussed. Fairly good agreement was obtained with literature data. These values may serve as reference values for subjects from a Turkish population. (author)

  17. Neutron activation analysis of ivory of African elephants

    International Nuclear Information System (INIS)

    Instrumental neutron activation analysis was applied to 61 ivory samples of which origin countries are known. 12 elements such as Br, Ca, Cl, Co, Cs, Fe, Mg, Mn, Na, Sc, Sr and Zn, were determined in all samples. The factor score of each sample was calculated for each factor by making use of principal component analysis in order to determine their origins. The results were compared with those by stable isotope analysis (13C and 15N). (author). 4 refs., 5 figs. 4 tabs

  18. Neutron activation analysis of ivory of African elephants

    International Nuclear Information System (INIS)

    Instrumental neutron activation analysis was applied to 80 samples from various African countries and 81 samples from the Kruger National Park in the Republic of South Africa. Twelve elements such as Br, Ca, Cl, Co, Cs, Fe, Mg, Mn, Na, Sc, Sr, and Zn, were determined in all samples. The factor scores of each sample were calculated from those elemental concentrations for the first and second factors to clarify the differences of samples from various African countries with those from Kruger Park. The results were compared with those by stable isotope analysis (13C and 15N). (author)

  19. A new microcomputer-controlled neutron activation and analysis system

    International Nuclear Information System (INIS)

    A microcomputer-controlled irradiation and measurement system and a microprocessor-controlled sample changer have been installed at the SLOWPOKE-2 Facility at the Royal Military College of Canada (RMC). These systems can provide the gamut of instrumental neutron activation analysis (INAA) techniques for the analyst. Custom software has been created for system control, data acquisition, and off-line spectral analysis using programs that incorporate Gaussian peak-fitting methods of analysis. The design and use of the equipment is discussed, and the performance is illustrated with results obtained from the analysis of marine sediment and biological reference materials

  20. Determination of mercury in dentists through Neutron activation analysis

    International Nuclear Information System (INIS)

    It was determined the mercury levels in urine through Neutron activation analysis to 25 dentists who have been exposed to mercury by several time periods, because of the routine manipulations of amalgams. The determined concentrations of mercury were less to 10 μ g Hg/l of urine. The results were founded inside the safety limits reported in the literature. The mercury levels in the dentists are associated with a wide variety of factors that contribute to their exposure as: number of years of dental practice, number of amalgams manipulated between others. (Author)

  1. Mercury determination in natural waters using neutron activation analysis

    International Nuclear Information System (INIS)

    Available as short communication only. An analytical method for quantitative determination of Mercury traces in river and sea water is proposed. The neutron activation method and radiochemical separation of Mercury by developing of C L4 Hg-2 complex, and their chromatographic separation using anionic exchange resin Dowex 1 X 8 of 400 mesh is used. The quantitative determination is done by gamma spectrometric analysis. The selection limits reached with this method showed that this is an amenable procedure in routine mercury determination in the ppb level, specially useful in the environmental contamination analysis. (author). 3 refs, 2 figs, 1 tab

  2. Calibration of HPGe detector for flowing sample neutron activation analysis

    International Nuclear Information System (INIS)

    This work is concerned with the calibration of the HPGe detector used in flowing sample neutron activation analysis technique. The optimum counting configuration and half-life based correction factors have been estimated using Monte Carlo computer simulations. Depending on detection efficiency, sample volume and flow type around the detector, the optimum geometry was achieved using 4 mm diameter hose rolled in spiral shape around the detector. The derived results showed that the half-life based efficiency correction factors are strongly dependent on sample flow rate and the isotope half-life. (author)

  3. Analysis by Neutron activation of the Calakmul jadeite mask

    International Nuclear Information System (INIS)

    It is very important to know the elemental composition of archaeological materials with the purpose to find relations that allow to establish their origin standards. the origin and present localization of pre hispanic archaeological pieces can lead to the determination of commercial routes and of technology transfer among different ancient cultures. In the present work it has been realized a systematic analysis using the Instrumental neutron activation analysis technique of three samples obtained from Calakmul jadeite mask, tomb I, that in addition to give a composition of constituent and trace elements detected by this technique it has leaded to establish an applicable methodology to the routine analysis of ceramics of historical interest. (Author)

  4. Neutron activation analysis of hair from breast cancer patients

    International Nuclear Information System (INIS)

    Hair samples from breast cancer patients were collected at the same time as tumour and normal tissues obtained during mastectomy, in order to determine elemental concentrations and investigate whether hair can act as an epidemiological monitor of the disease. Instrumental neutron activation analysis was used and concentrations for Na, Mg, S, Cl, Ca, Mn, Cu, Zn, Br, I, Sb, Ba, Au and Hg in the hair samples measured. No strong correlations were found between the concentrations of Cl, Cu, Zn and Br in hair and those in tumour tissues and in normal tissues. The level of Zn in the patients hair is low and that of Ca very high

  5. Elemental characterization of Brazilian beans using neutron activation analysis

    International Nuclear Information System (INIS)

    Beans are important for many developing countries as a source of protein and mineral nutrients. Here, ten commercial types of Brazilian beans, from the species Phaseolus vulgaris (common beans) and Vigna unguiculata (cowpeas), were analyzed by neutron activation analysis for the determination of Br, Ca, Co, Cs, Fe, K, Mo, Na, Rb, Sc and Zn. There were statistical differences (p/0.05) amongst the commercial types, except for Br, Rb and Sc. In general, non-essential elements showed high variability, indicating that the origin of beans had a strong influence on the mass fraction of such elements. (author)

  6. Multielemental analysis of metallurgical samples by thermal neutron activation

    International Nuclear Information System (INIS)

    Instrumental neutron activation analysis (INAA) was applied to investigate a total of 16 samples of raw materials, intermediate and final products involved in metallurgical processes in Romanian Iron and Steel Works Sidex Galatzy; iron ores and pellets from different regions of the world cast iron, slag and steels. A series of chemical elements was determined in the analyzed samples: Al, As, Ce, Co, Cr, Fe, La, Mn, Na, Sc, Sm, V, W. A qualitative discussion regarding the passing of some elements with different chemical affinity for oxygen compared to that of iron, from the raw materials to slag or to finite products is presented. (author). 11 refs., 2 tabs

  7. Neutron activation analysis for investigation of chosen food products

    International Nuclear Information System (INIS)

    In this work neutron activation analysis is applied for investigation of the elemental composition of Amaranths seeds. The characterization by multi-elemental instrumental NAA is enriched by the results of radiochemical NAA for cobalt, molybdenum and uranium content. The comparison of the results, for three sorts of edible flour, commercially available: soya Flour, Corn Bean Flour and Amaranths Flour, is presented. The validation of the analytical methods used was carried out on the basis of participation in the interlaboratory comparison organised by INCT and NIST. (author)

  8. Teaching chemistry with neutron activation analysis at Dalhousie University

    International Nuclear Information System (INIS)

    The Dalhousie University SLOWPOKE-2 Reactor (DUSR) has been operating since July 1976 and has proven to be an invaluable tool in many teaching programs. These reactors are inherently safe and are designed to serve teaching and research needs of the universities, research centers, hospitals, etc. Since the DUSR has been, from its inception, associated with the Trace Analysis Research Centre, which is the Analytical Chemistry Division of the Department of Chemistry, the main thrust of its use continues to be in the field of nuclear analytical chemistry. Both teaching and research programs involve trace element analysis by neutron activation

  9. Validation of computational methods for treatment planning of fast-neutron therapy using activation foil techniques

    Energy Technology Data Exchange (ETDEWEB)

    Nigg, D.W.; Wemple, C.A.; Hartwell, J.K.; Harker, Y.D.; Venhuizen, J.R. [Idaho National Engineering and Environmental Lab., Idaho Falls, ID (United States); Risler, R. [Univ. of Washington Medical Center, Seattle, WA (United States)

    1997-12-01

    A closed-form direct method for unfolding neutron spectra from foil activation data is presented. The method is applied to measurements of the free-field neutron spectrum produced by the proton-cyclotron-based fast-neutron radiotherapy facility at the University of Washington (UW) School of Medicine. The results compare favorably with theoretical expectations based on an a-priori calculational model of the target and neutron beamline configuration of the UW facility.

  10. Neutron activation analysis in teaching analytical chemistry at UCI

    International Nuclear Information System (INIS)

    The undergraduate curriculum in chemistry at the University of California at Irvine has included practice with experiments in radiochemistry and activation analysis since 1968, 3 years after the campus was founded. In 1969, a TRIGA nuclear reactor was installed that operates at 250 kW steady state or can pulse to ∼10 MW of peak power. This has been the main activation source, although experiments have also been carried out by students using a 14-MeV neutron generator (Kaman Sciences, Model 711) and a small (1-μCi) 252Cf source on loan from the US Department of Energy. The majority of the experience has been within a junior/senior-level elective course in radioisotope techniques. However, experiments were also introduced by this author into the required instrumental analysis course. A very worthwhile experience was gained when students were assigned an unknown material (sometimes an inexpensive standard reference material) and asked to determine the concentration of a single trace element by two or three different techniques (atomic absorption, polarography, or derivative spectrophotometry) in addition to instrumental neutron activation analysis (INAA)

  11. Enzyme hydration, activity and flexibility : A neutron scattering approach

    Energy Technology Data Exchange (ETDEWEB)

    Kurkal-Siebert, V [University of Heidelberg; Finney, J.L. [University College, London; Daniel, R. M. [University of Waikato, New Zealand; Smith, Jeremy C [ORNL

    2006-01-01

    Recent measurements have demonstrated enzyme activity at hydrations as low as 3%. The question of whether the hydration-induced enzyme flexibility is important for activity is addressed by performing picosecond dynamic neutron scattering experiments on pig liver esterase powders at various temperatures as well as solutions. At all temperatures and hydrations investigated here, significant quasielastic scattering intensity is found in the protein, indicating the presence of anharmonic, diffusive motion. As the hydration increases a temperature-dependent dynamical transition appears and strengthens involving additional diffusive motion. At low temperature, increasing hydration resulted in lower flexibility of the enzyme. At higher temperatures, systems containing sufficient number of water molecules interacting with the protein exhibit increased flexibility. The implication of these results is that, although the additional hydration-induced diffusive motion and flexibility at high temperatures in the enzyme detected here may be related to increased activity, they are not required for the enzyme to function.

  12. Activation of cobalt by neutrons from the Hiroshima bomb

    International Nuclear Information System (INIS)

    A study has been completed of cobalt activation in samples from two new locations in Hiroshima. The samples consisted of a piece of steel from a bridge located at a distance of about 1300 m from the hypocenter and pieces of both steel and concrete from a building located at approximately 700 m. The concrete was analyzed to obtain information needed to calculate the cobalt activation in the two steel samples. Close agreement was found between calculated and measured values for cobalt activation of the steel sample from the building at 700 m. It was found, however, that the measured values for the bridge sample at 1300 m were approximately twice the calculated values. Thus, the new results confirm the existence of a systematic error in the transport calculations for neutrons from the Hiroshima bomb. 52 refs., 32 figs., 16 tabs

  13. Foote Brook Macroinvertebrate Biomonitoring-Phase I in Johnson, Vermont

    Data.gov (United States)

    Vermont Center for Geographic Information — The Foote Brook Biomonitoring Project, Phase I geospatial dataset consists of data from the biomonitoring of benthic macroinvertebrates at three sites located along...

  14. Current studies of biological materials using instrumental and radiochemical neutron activation analysis

    International Nuclear Information System (INIS)

    Instrumental neutron activation analysis still remains the preferred option when analysing the trace element distribution in a wide rage of materials by neutron activation analysis. However, when lower limits of detection are required or major interferences reduce the effectiveness of this technique, radiochemical neutron activation analysis is applied. This paper examines the current use of both methods and the development of rapid radiochemical techniques for analysis of the biological materials, hair, cow's milk, human's milk, milk powder, blood and blood serum

  15. Quality Assurance and Control in Laboratory using Neutron Activation Analysis

    International Nuclear Information System (INIS)

    In accordance with the increment of international trade associated with the worldwide globalization, the importance of quality assurance and control for the commodity produced from one's own country has been stressed. ISO (International Organization for Standards) defines quality control as 'the operational techniques and activities that are used to fulfill the requirements for quality'. Since 1996, the HANARO research reactor in the Korea Atomic Energy Research Institute has been operated thereafter initial critical operation on April 1995. Neutron activation analysis system and applied techniques which is one of a nuclear analytical technologies using reactor neutrons has been developed for user's supporting and the establishment of the quality system for a measurement and analysis, testing and inspection was implemented successfully. On the basis of the qualified NAA system, the test and measurement of more than 1500 samples which is requested from 30 organizations including industrial companies, universities and institutes carried out in NAA laboratory annually. Moreover, as the goal of mutual recognition agreement (MRA) which can be removed a technical barrier in international trade, the objectivity and the confidence of analytical quality in NAA laboratory became established through the installation of international accreditation system by implementing analytical quality system in accordance with international standards in 2001. The aim of the report was to summarize the technical management of introduction, methods and the results for a quality control and assurance which should be performed in NAA technique using the HANARO research reactor. The report will help building up effective quality control strategy in the future

  16. High precision methods of neutron activation analysis applied to geochemistry

    International Nuclear Information System (INIS)

    Neutron activation analysis is a technique for measuring abundances of chemical elements, which differs from other methods in that it is based upon nuclear reactions instead of chemistry. This characteristic has special relevance for geochemistry because of its inherent sensitivity for trace elements which cannot be reached by other methods. 99% of the earth's crust is made up of just 8 elements, whereas the remaining 1% must accommodate 70-odd rock building trace elements of which about half can be measured by neutron activation analysis. In recent years, there has been much interest in these trace elements because they encompass diverse chemical properties. The present discussion of the technique is based upon more than 15 years of experience at the Lawrence Berkeley Laboratory and The Hebrew University of Jerusalem. This is not meant to intimate that the practices in other laboratories do not merit attention. Perhaps our approach differs from other published work in the emphasis given to sources of error and learning how to control them

  17. The Background in Flow Measurement using Pulsed Neutron Activation

    International Nuclear Information System (INIS)

    In flow measurement with Pulsed Neutron Activation (PNA), water flowing in a pipe is activated with 14 MeV neutrons, producing the radioactive nuclide 16N. The gamma radiation emitted from this radionuclide will produce a characteristic peak in a time spectrum from a detector downstream. Experiments have shown that the peak is superimposed on a background distribution, which can affect the measurement. As it is necessary to correct for the background, different subtraction methods have been used in the past, although the origin of the background has not been known. In this work the source of the background has been investigated. It has been found that there are two components of the background: one time dependent and one time independent. The time-dependent component is shown to be caused by stationary 16N in the surroundings. A method for subtracting the background in a reproducible way has been developed. This was done by fitting the peak with an empirical function consisting of several Taylor distributions

  18. Cyclic neutron activation analysis of fluorine concentration in Chinese teas

    International Nuclear Information System (INIS)

    Based on advantage of cyclic neutron activation of 20F(t1/2=11.03 s), cyclic neutron activation analysis (CNAA) and three traditional methods, i.e.UV-vis spectroscopy, fluorine ion selective electrode, and chromatography of ions,were used to determine fluorine concentration in standard reference materials of tea (GBW10016). Compared with the three traditional methods, CNAA is accurate, sensitive, time-saving, little sample amount,strong traceability and good anti-interference. Fluorine concentrations in 16 commercial teas of four categories were determined by using CNAA. The results showed that fluorine concentrations of brick tea, black tea, oolong tea and green tea are 60 276, 54 66, 37 59 and 34 49 mg/kg, respectively. It was also found that the fluorine concentrations in different tea categories are likely attributed to their raw materials and production process. Fluoride concentration in one tea product was 276 mg/kg, while the national standard is ≤200 mg/kg. (authors)

  19. Two-phase flow measurement by pulsed neutron activation techniques

    International Nuclear Information System (INIS)

    The Pulsed Neutron Activation (PNA) technique for measuring the mass flow velocity and the average density of two-phase mixtures is described. PNA equipment can be easily installed at different loops, and PNA techniques are non-intrusive and independent of flow regimes. These features of the PNA technique make it suitable for in-situ measurement of two-phase flows, and for calibration of more conventional two-phase flow measurement devices. Analytic relations governing the various PNA methods are derived. The equipment and procedures used in the first air-water flow measurement by PNA techniques are discussed, and recommendations are made for improvement of future tests. In the present test, the mass flow velocity was determined with an accuracy of 2%, and average densities were measured down to 0.08 g/cm3 with an accuracy of 0.04 g/cm3. Both the accuracy of the mass flow velocity measurement and the lower limit of the density measurement are functions of the injected activity and of the total number of counts. By using a stronger neutron source and a larger number of detectors, the measurable density can be decreased by a factor of 12 to .007 g/cm3 for 12.5 cm pipes, and to even lower ranges for larger pipes

  20. Assessment of the traffic-related elements Ba, Cr and Zn during and after the construction of a peripheral highway using Tillandsia usneoides as atmospheric biomonitor

    Energy Technology Data Exchange (ETDEWEB)

    Figueiredo, Ana M.G.; Silva, Barbara C. da, E-mail: anamaria@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Nievola, Catarina C.; Alves, Edenise S.; Domingos, Marisa, E-mail: ccnievola@uol.com.br, E-mail: ealves@ibot.sp.gov.br, E-mail: mmingos@superig.com.br [Instituto de Botanica de Sao Paulo, Sao Paulo, SP (Brazil)

    2013-07-01

    Tillandsia usneoides (L.) L. is an aerial epiphytic bromeliad that lives on trees or other kinds of inert substratum, absorbing water and nutrients directly from the environment. Due to this characteristic, this species also accumulates pollutants present in the atmosphere. In this study, T. usneoides was used as biomonitor aiming to verify if the construction of the western and southern parts of the peripheral highway Mario Covas (SP-21) in Sao Paulo city would alter the profile of atmospheric contamination by Ba, Cr and Zn in the region. These elements are often associated with traffic and can indicate contaminated urban areas. This knowledge is of great interest to the city, which has one of the biggest vehicle fleets in the world, with more than seven million circulating motor vehicles and serious environmental problems due to air pollution. Neutron Activation Analysis was employed as analytical technique. Samples of T. usneoides were irradiated at the IEA-R1 nuclear reactor at IPEN-CNEN/SP, and the induced activity was measured by high resolution gamma-ray spectrometry. Increasing concentrations of Ba, Cr and Zn were observed in the biomonitor after the inauguration of the highway, indicating that these elements originated from vehicular emissions. (author)

  1. Fast-neutron activation analysis of light elements

    International Nuclear Information System (INIS)

    Full text: The determination of lithium, carbon, oxygen, nitrogen and other light chemical elements in various modern materials in microgram level is of importance for analytical science. As it is well-known, a thermal neutron activation of C, H, N, and O produces negligible γ-ray activity. 13C (n, γ) 14C and 2H (n, γ) 3H reactions produce very small activities of the non- γ- emitters 3H and 14C, and the 19O (n, γ)19O and 15N(n, γ)16N reactions give very short lived 19O (27 sec) and 16N (7.1 sec). All of these reactions have extremely low thermal neutron cross sections. Therefore a major advantage of the instrumental neutron activation analysis (INAA) is the determination of trace elements in biological, medical and environmental materials. For this reason the above mentioned problems are solved with use of some variants of nuclear analytical techniques based on application of charged particle accelerators. However, there are several non-traditional reactor activation analysis techniques to solve such problems which have been developed and applied in various fields of semiconductor industry, biology, geology. In recent years these techniques were named as the nuclear reactor based charged particles activation analysis (NRCPAA). We distinguished two possible applications of a nuclear reactor as charged particles source. During last years the capabilities of the NRCPAA were investigated intensively and some our results were applied to determine light elements contents [1,2]. The recoil protons are produced as the result of (n, p) elastic and inelastic scattering interaction of fast neutrons with nucleus of light elements, for example, hydrogen. These protons are applied for the development of proton activation analysis for the determination of large concentrations of Li, B and O. The non-destructive activation analysis with use of 14-MeV fast neutrons (FNAA) is the most suitable method for analysis of N, P and Si. FNAA was applied for determination of nitrogen

  2. Multi-element atmospheric deposition in Macedonia studied by the moss biomonitoring technique.

    Science.gov (United States)

    Barandovski, Lambe; Frontasyeva, Marina V; Stafilov, Trajče; Šajn, Robert; Ostrovnaya, Tatyana M

    2015-10-01

    Moss biomonitoring technique using moss species Homolothecium lutescens (Hedw.) Robins and Hypnum cupressiforme (Hedw.) was applied to air pollution studies in the Republic of Macedonia. The study was performed in the framework of the International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops under the auspices of the United Nations Economic Commission for Europe (UNECE) Convention on Long-Range Transboundary Air Pollution (LRTAP). The presence of 47 elements was determined by instrumental epithermal neutron activation analysis, atomic absorption spectrometry and atomic emission spectrometry with inductively coupled plasma. Normality of the datasets of elements was investigated, and Box-Cox transformation was used in order to achieve normal distributions of the data. Different pollution sources were identified and characterized using principal component analysis (PCA). Distribution maps were prepared to point out the regions most affected by pollution and to relate this to the known sources of contamination. The cities of Veles, Skopje, Tetovo, Radoviš and Kavadarci were determined to experience particular environmental stress. Moreover, three reactivated lead-zinc mines were also shown to contribute to a high content of lead and zinc in the eastern part of the country. However, a comparison with the previous moss survey conducted in 2005 showed a decreasing trend of pollution elements that are usually associated with emission from industrial activities. PMID:26062458

  3. Current status of neutron activation analysis using the Dalat Nuclear Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Van Suc; Nguyen Mong Sinh [Nuclear Research Institute, Dalat (Viet Nam)

    1999-10-01

    Neutron activation analysis is one of the most sensitive, rapid, accurated methods for determination of trace elements in different materials. A review is made of the current status of the activities and the results in studying and developing NAA (Neutron Activation Analysis) at the Dalat Nuclear Research Institute and applying this method to different sectors of science and technology in Vietnam. (author)

  4. Total body neutron activation analysis of calcium: calibration and normalisation

    International Nuclear Information System (INIS)

    An irradiation system has been designed, using a neutron beam from a cyclotron, which optimises the uniformity of activation of calcium. Induced activity is measured in a scanning, shadow-shield whole-body counter. Calibration has been effected and reproducibility assessed with three different types of phantom. Corrections were derived for variations in body height, depth and fat thickness. The coefficient of variation for repeated measurements of an anthropomorphic phantom was 1.8% for an absorbed dose equivalent of 13 mSv (1.3 rem). Measurements of total body calcium in 40 normal adults were used to derive normalisation factors which predict the normal calcium in a subject of given size and age. The coefficient of variation of normalised calcium was 6.2% in men and 6.6% in women, with the demonstration of an annual loss of 1.5% after the menopause. The narrow range should make single measurements useful for diagnostic purposes. (author)

  5. Conventional radiometric methods of analysis including neutron activation

    International Nuclear Information System (INIS)

    The chapter aims primarily to provide a reference with which the various mass spectrometric methods may be compared. The fundamental problems created by low specific activity in the measurement of very long-lived radionuclides using radiometric techniques are noted and discussed in terms of the different types of decay, background count rates, source weight and spectral interferences. An attempt is made to identify typical detection limits for the radiometric determination of the various long-lived radionuclides. The use of neutron activation as a means of enhancing sensitivity or convenience of measurement for long-lived radionuclides is described with appropriate illustrations. Mass spectrometry and radiometry are seen as complementary, not competitive techniques for the measurement of radioactive materials, each with its own advantages and disadvantages. (author). 21 refs, 2 figs, 6 tabs

  6. Epithermal Neutron Activation Analysis of the Asian Herbal Plants

    Science.gov (United States)

    Baljinnyam, N.; Jugder, B.; Norov, N.; Frontasyeva, M. V.; Ostrovnaya, T. M.; Pavlov, S. S.

    2011-06-01

    Asian medicinal herbs Chrysanthemum (Spiraea aquilegifolia Pall.) and Red Sandalwood (Pterocarpus Santalinus) are widely used in folk and Ayurvedic medicine for healing and preventing some diseases. The modern medical science has proved that the Chrysanthemum (Spiraea aquilegifolia Pall.) possesses the following functions: reducing blood press, dispelling cancer cell, coronary artery's expanding and bacteriostating and Red Sandalwood (Pterocarpus Santalinus) is recommended against headache, toothache, skin diseases, vomiting and sometimes it is taken for treatment of diabetes. Species of Chrysanthemums were collected in the north-eastern and central Mongolia, and the Red Sandalwood powder was imported from India. Samples of Chrysanthemums (branches, flowers and leaves) (0.5 g) and red sandalwood powder (0.5 g) were subjected to the multi-element instrumental neutron activation analysis using epithermal neutrons (ENAA) at the IBR-2 reactor, Frank Laboratory of Neutron Physics (FLNP) JINR, Dubna. A total of 41 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Cd, Cs, Ba, La, Hf, Ta, W, Sb, Au, Hg, Ce, Nd, Sm, Eu, Tb, Dy, Yb, Th, U, Lu) were determined. For the first time such a large group of elements was determined in the herbal plants used in Mongolia. The quality control of the analytical results was provided by using certified reference material Bowen Cabbage. The results obtained are compared to the "Reference plant» data (B. Markert, 1992) and interpreted in terms of excess of such elements as Se, Cr, Ca, Fe, Ni, Mo, and rare earth elements.

  7. Epithermal Neutron Activation Analysis of the Asian Herbal Plants

    International Nuclear Information System (INIS)

    Asian medicinal herbs Chrysanthemum (Spiraea aquilegifolia Pall.) and Red Sandalwood (Pterocarpus Santalinus) are widely used in folk and Ayurvedic medicine for healing and preventing some diseases. The modern medical science has proved that the Chrysanthemum (Spiraea aquilegifolia Pall.) possesses the following functions: reducing blood press, dispelling cancer cell, coronary artery's expanding and bacteriostating and Red Sandalwood (Pterocarpus Santalinus) is recommended against headache, toothache, skin diseases, vomiting and sometimes it is taken for treatment of diabetes. Species of Chrysanthemums were collected in the north-eastern and central Mongolia, and the Red Sandalwood powder was imported from India. Samples of Chrysanthemums (branches, flowers and leaves)(0.5 g) and red sandalwood powder (0.5 g) were subjected to the multi-element instrumental neutron activation analysis using epithermal neutrons (ENAA) at the IBR-2 reactor, Frank Laboratory of Neutron Physics (FLNP) JINR, Dubna. A total of 41 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Cd, Cs, Ba, La, Hf, Ta, W, Sb, Au, Hg, Ce, Nd, Sm, Eu, Tb, Dy, Yb, Th, U, Lu) were determined. For the first time such a large group of elements was determined in the herbal plants used in Mongolia. The quality control of the analytical results was provided by using certified reference material Bowen Cabbage. The results obtained are compared to the ''Reference plant? data (B. Markert, 1992) and interpreted in terms of excess of such elements as Se, Cr, Ca, Fe, Ni, Mo, and rare earth elements.

  8. Nondestructive testing: Neutron radiography and neutron activation. (Latest citations from the INSPEC: Information services for the physics and engineering communities database). Published Search

    International Nuclear Information System (INIS)

    The bibliography contains citations concerning the technology of neutron radiography and neutron activation for nondestructive testing of materials. The development and evaluation of neutron activation analysis and neutron diffraction examination of liquids and solids are presented. Citations also discuss nondestructive assay, verification, evaluation, and multielement analysis of biomedical, environmental, industrial, and geological materials. Nondestructive identification of chemical agents, explosives, weapons, and drugs in sealed containers are explored. (Contains a minimum of 83 citations and includes a subject term index and title list.)

  9. Silver activated counter detector for measurements of high intensity fast neutron burst

    International Nuclear Information System (INIS)

    In fusion facilities, such as Z pinch, plasma focus or laser driven experiments, fast neutrons are produced in the form of a burst of radiation. For these kinds of sources, moderation of the neutron energy and silver activation is one of the most common techniques for measurement of the neutron yield. In the recent years, the study of this detection system has been revisited in order to improve the calibration methodologies, and to study the effects of moderator geometry for measurements in low intensity burst neutron sources. In this work, the design, construction and characterization of a silver activated neutron counter for measurements in high intensity neutron burst sources are reported. For such sources (Y4π > 109 n/burst), the effects of moderator geometry, as well as, the systematic effects introduced in the measurement by dead time, after irradiation of the detector by a burst of neutrons, are discussed and included in the measurement methodology

  10. Evaluation of Am-Li neutron spectra data for active well type neutron multiplicity measurements of uranium

    Science.gov (United States)

    Goddard, Braden; Croft, Stephen; Lousteau, Angela; Peerani, Paolo

    2016-09-01

    Safeguarding nuclear material is an important and challenging task for the international community. One particular safeguards technique commonly used for uranium assay is active neutron correlation counting. This technique involves irradiating unused uranium with (α, n) neutrons from an Am-Li source and recording the resultant neutron pulse signal which includes induced fission neutrons. Although this non-destructive technique is widely employed in safeguards applications, the neutron energy spectra from an Am-Li sources is not well known. Several measurements over the past few decades have been made to characterize this spectrum; however, little work has been done comparing the measured and theoretical spectra of various Am-Li sources to each other. This paper examines fourteen different Am-Li spectra, focusing on how these spectra affect simulated neutron multiplicity results using the code Monte Carlo N-Particle eXtended (MCNPX). Two measurement and simulation campaigns were completed using Active Well Coincidence Counter (AWCC) detectors and uranium standards of varying enrichment. The results of this work indicate that for standard AWCC measurements, the fourteen Am-Li spectra produce similar doubles and triples count rates. The singles count rates varied by as much as 20% between the different spectra, although they are usually not used in quantitative analysis, being dominated by scattering which is highly dependent on item placement.

  11. The calibration of DD neutron indium activation diagnostic for Shenguang-III facility

    CERN Document Server

    Song, Zi-Feng; Liu, Zhong-Jie; Zhan, Xia-Yu; Tang, Qi

    2014-01-01

    The indium activation diagnostic was calibrated on an accelerator neutron source in order to diagnose deuterium-deuterium (DD) neutron yields of implosion experiments on Shenguang-III facility. The scattered neutron background of the accelerator room was measured by placing a polypropylene shield in front of indium sample, in order to correct the calibrated factor of this activation diagnostic. The proper size of this shield was given by Monte Carlo simulation software. The affect from some other activated nuclei on the calibration was verified by judging whether the measured curve obeys exponential decay and contrasting the half life of the activated sample. The calibration results showed that the linear range reached up to 100 cps net count rate in the full energy peak of interest, the scattered neutron background of accelerator room was about 9% of the total neutrons and the possible interferences mixed scarcely in the sample. Subtracting the portion induced by neutron background, the calibrated factor of ...

  12. Praseodymium activation detector for measuring bursts of 14 MeV neutrons

    International Nuclear Information System (INIS)

    A new, accurate, neutron activation detection scheme for measuring pulsed neutrons has been designed and tested. The detection system is sensitive to neutrons with energies above 10 MeV; importantly, it is insensitive to gamma radiation 141Pr, an element that has a single, naturally occurring isotope, a significant n,2n cross-section, and decays by positron emission that result in two coincident 511 keV photons. Neutron fluences are thus inferred by relating measured reaction product decay activity to fluence. Specific sample activity is measured using the sum-peak method to count gamma-ray coincidences from the annihilation of the positron decay products. The system was tested using 14 and 2.45 MeV neutron bursts produced by NSTec Dense Plasma Focus Laboratory fusion sources. Lead, copper, beryllium, and silver activation detectors were compared. The detection method allows measurement of 14 MeV neutron yield with a total error of ∼18%.

  13. RACC-PULSE, Neutron Activation in Fusion Reactor System

    International Nuclear Information System (INIS)

    1 - Description of program or function: CCC-0388/RACC was specifically developed to compute the radioactivity and radioactivity-related parameters (e.g. afterheat, biological hazard potential, etc.) due to neutron activation within Inertial Fusion Energy and Magnetic Fusion energy reactor systems. It can also be utilized to compute the radioactivity in fission, accelerator or any other neutron generating and neutron source system. This new designated RACC-PULSE is based on CCC-0388 and has the capability to model irradiation histories of varying flux levels having varying pulse widths (on times) and dwell periods (off times) and varying maintenance periods. This provides the user with the flexibility of modeling most any complexity of irradiation history beginning with simple steady state operating systems to complex multi-flux level pulse/intermittent operating systems. 2 - Method of solution: The solution method implemented within the RACC-PULSE code is a matrix based method which relies on the evaluation of the Matrix Exponential for the pulse period (on period), dwell period (off time) and post shutdown periods. For the pulsed and dwell periods, the Matrix Exponential was evaluated using the squaring and scaling technique outlined in a review article by Molar and Van Loan entitled Nineteen Dubious Ways to Compute the Exponential of a Matrix. A balanced binary tree method utilized for parameter storage in information systems was employed to evaluate the linear chains constructed for the post shutdown period. The RACC-Pulse code retains the capability of modeling the standard slab, cylinder, sphere and torus geometries in multi-dimensions as well as the point or zero-dimension geometry for Monte Carlo code interfacing. It provides easy interfacing with many of the standard multigroup, multidimensional neutron/photon transport code systems currently employed by the fusion community and implemented on the UNICOS Cray 2 System at NERSC. An auxiliary code is provided

  14. Correction for neutron self-shielding in large-sample prompt-gamma neutron activation analysis. Determination of macroscopic neutron cross sections

    International Nuclear Information System (INIS)

    When a sample is analysed with neutron activation analysis (NAA) neutron self-shielding and gamma self-absorption affect the accuracy. Both effects become even more important when the mass of a sample analysed is changed from small (say, 1 g) to large (say 30 kg). Therefore, corrections have to be carried out. Correction method for neutron self-shielding is considered for a thermal neutron beam irradiating large homogeneous samples for prompt-gamma NAA (PGNAA). The correction method depends on the macroscopic scattering and absorption cross sections of the sample. To avoid doing experiments with samples with different macroscopic scattering and absorption cross sections, the Monte Carlo model MCNP is applied in the development of the correction method. The computational development of the method to determine these cross sections through flux monitoring outside the sample is described. (author)

  15. Cosmetics chemical composition characterization by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Brazil is in the third position in the world's cosmetics market. It is an expanding and growing market where new products and manufacturing processes are in a constant and steady expansion. Therefore, it is mandatory that the composition of the products is well known in order to guarantee safety and quality of daily used cosmetics. The Brazilian National Health Surveillance Agency (ANVISA) has issued a resolution, RDC No. 48, March 16, 2006, which defines a 'List of Substances which can not be used in personal hygiene products, cosmetics and perfumes'. In this work, samples of locally manufactured and imported cosmetics (lipsticks, eye shadows, etc.) were analyzed using the Instrumental Neutron Activation Analysis technique. The samples were irradiated in the TRIGA IPR-R1 reactor of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN), on a 100kW thermal power, with a thermal neutron fluence rate about 8x1011ncm-2s-1. The analysis has detected the chemical elements Br, Ba, Ga, Na, K, Sc, Fe, Cr, Zn, Sm, W, La, Rb, Cs, Ta, Ge, Co, U, Ti, V, Cl, Al, Mn and Cu. The concentrations of these elements are on a range from 5 to 3000μg.g-1. Some chemical elements observed in samples (Cl, Br, Cr, U) are included at ANVISA prohibitive list. (author)

  16. Determination of impurities in zirconium oxide by neutron activation analysis

    International Nuclear Information System (INIS)

    The instrumental method of neutron activation analysis was applied to the determination of impurities in zirconium oxide samples produced at IPEN-CNEN/SP. The samples and the standards of the elements to be determined were irradiated in the IEA-R1 research reactor under a thermal neutron flux from 1011 to 1012 n.cm-2.s-1 for a period that varied from 3 min to 8 h and after adequate cooling time they were counted in a Ge(Li) detector coupled to a multichannel analyzer. The impurities of Al, Dy, Eu, Fe, Hf, Mn, Sc, Ta, Tb, Th and V were determined quantitatively in zirconium oxide samples. The relative standard deviations of the results for several impurities were, in general, lower than 15%. In order to investigate the accuracy obtainable with the method a standard reference material Zircaloy 2 - SRM-360a from NIST was analysed. The quantitative determination limit was also evaluated for impurities present in zirconium oxide samples. (author)

  17. Reactor neutron activation analysis on reference materials from intercomparison runs

    International Nuclear Information System (INIS)

    A review of using the Instrumental Neutron Activation Analysis (INAA) technique in our laboratory to determine major, minor and trace elements in mineral and biological samples from international intercomparison runs organised by IAEA Vienna, IAEA-MEL Monaco, 'pb-anal' Kosice, INCT Warszawa and IPNT Krakow is presented. Neutron irradiation was carried out at WWR-S reactor in Bucharest (short and long irradiation) during 1982-1997 and at TRIGA reactor in Pitesti (long irradiation) during the later period. The following type of materials were analysed: soils, marine sediments, uranium phosphate ore, water sludge, copper flue dust, whey powder, yeast, cereal flour (rye and wheat), marine animal tissue (mussel, garfish and tuna fish), as well as vegetal tissue (seaweed, cabbage, spinach, alfalfa, algae, tea leaves and herbs). The following elements could be, in general, determined: Ag, As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, K, La, Lu, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, U, W, Yb and Zn of long-lived radionuclides, as well as Al, Ca, Cl, Cu, Mg, Mn, and Ti of short-lived radionuclides. Data obtained in our laboratory for various matrix samples presented and compared with the intercomparison certified values. The intercomparison exercises offer to the participating laboratories the opportunity to test the accuracy of their analytical methods as well as to acquire valuable Reference Materials/ standards for future analytical applications. (authors)

  18. Determination of the specific activity of carrier-free 125I preparations by neutron activation analysis

    DEFF Research Database (Denmark)

    Heydorn, Kaj

    Chemical methods are unsuitable for the determination of the specific activity of commerical125I preparations because of the unknown chemical state of the iodine in solutions more than a few weeks old.125I and127I were determined in samples from seven different manufacturers by instrumental neutron...

  19. Limits of detection in instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Lower limits of detection (LLODs), frequently referred to simply as limits of detection and abbreviated as LODs, often appear in the literature of analytical chemistry - for numerous different methods of elemental and/or molecular analysis. In this chapter, one particular method of quantitative elemental analysis, that of instrumental neutron activation analysis (INAA), is the subject discussed, with reference to LODs. Particularly in the literature of neutron activation analysis (NAA), many tables of 'interference-free' NAA LODs are available. Not all of these are of much use, because (1) for many the definition used for LOD is not clear, or reasonable, (2) for many, the analysis conditions used are not clearly specified, and (3) for many, the analysis conditions used are specified, but not very practicable for most laboratories. For NAA work, such tables of interference-free LODs are, in any case, only applicable to samples in which, at the time of counting, only one radionuclide is present to any significant extent in the activated sample. It is important to note that tables of INAA LODs, per se, do not exist - since the LOD for a given element, under stated analysis conditions, can vary by orders of magnitude, depending on the elemental composition of the matrix in which it is present. For any given element, its INAA LOD will always be as large as, and usually much larger than, its tabulated 'interference-free' NAA LOD - how much larger depending upon the elemental composition of the matrix in which it is present. As discussed in this chapter, however, an INAA computer program exists that can calculate realistic INAA LODs for any elements of interest, in any kind of specified sample matrix, under any given set of analysis conditions

  20. Research and development activities of the Neutron Physics Division for the period January 1980 - December 1980

    International Nuclear Information System (INIS)

    The highlights of the research and development (R and D) activities of the Neutron Physics Division of the Bhabha Atomic Research Centre, Bombay, during January - December 1980 are summarised. The R and D activities are in the fields of critical and subcritical fission systems, the plasma focus device, applied neutron physics, neutron and X-ray crystallography, materials physics and seismology. (M.G.B.)

  1. Analysis of Some Egyptian Cosmetic Samples by Fast Neutron Activation Analysis

    CERN Document Server

    Medhat, M E; Fayez-Hassan, M

    2001-01-01

    A description of D-T neutron generator (NG) is presented. This generator can be used for fast neutron activation analysis applied to determine some selected elements, especially light elements, in different materials. In our work, the concentration of the elements Na, Mg, Al, Si, K, Cl, Ca and Fe, were determined in two domestic brands of face powder by using 14 MeV neutron activation analysis.

  2. Use of cryopreserved peripheral mononuclear blood cells in biomonitoring

    DEFF Research Database (Denmark)

    Risom, Lotte; Knudsen, Lisbeth E.

    1999-01-01

    /T-lymphocytes and monocytes was measured in phytohemaglutinin (PHA)-stimulated cultures at different time intervals. The results showed a higher DNA repair activity in cryopreserved samples compared with fresh samples. We also found differences in mutant frequencies with higher values in fresh samples. A......This study was performed to investigate the effect of storing blood samples by freezing on selected biomarkers and possible implications for biomonitoring. Comparative measurements were performed in order to investigate the use of cryopreserved vs. freshly separated peripheral mononuclear blood...... significant correlation of frequencies was seen when comparing fresh with cryopreserved samples. Furthermore we recommend fresh human plasma used in UDS incubation media....

  3. Biomonitoring of genotoxic exposure among stainless steel welders

    DEFF Research Database (Denmark)

    Knudsen, Lisbeth E.; Boisen, T; Christensen, J M;

    1992-01-01

    . Environmental monitoring of welding fumes and selected metal oxides, biomonitoring of chromium and nickel in serum and urine and mutagenic activity in urine, and evaluation of semen quality were also done. Manual metal arc (MMA) welding and tungsten inert gas (TIG) welding were the dominant welding processes. A...... lymphocytes in exposed persons compared with non-exposed are suggested. MMA welding gave the highest exposure to chromium, an increased number of chromosomal aberrations and a decrease in SCE when compared with TIG welding. Consequently improvements in the occupational practice of stainless steel welding with...

  4. Neutron activation analysis of medieval and early modern times ceramics

    International Nuclear Information System (INIS)

    Provenience studies of medieval and early modern times ceramics from the Eastern Danube area of Austria have been performed by instrumental neutron activation analysis. All sherds examined were selected from pottery which was specially charactrized by pottery marks ('Cross Potent', 'Crossmark within a circle', 'Latin Cross', 'Cross Paty'). With respect to the chemical composition five different pottery groups could be evaluated by cluster analysis. Archaeological results: The'Cross Patent' was used by different potter's workshops whereas the 'Crossmark within a circle' was more likely restricted to one manufacture entre. The distribution of the 'Latin Cross' and The 'Cross Paty' over all five clusters indicated the usage of clay from different deposits. The assignment of the 'Cross Paty' exclusively to the area of Passau could be disproved. (Author)

  5. Neutron activation analysis of stable elements in marine algae

    International Nuclear Information System (INIS)

    The nuclear industry has grown during the last decades and continuing growth is predicted. Although considerable efforts are being made to minimize the release of the increasing amounts of radioactive wastes into marine environment, it is evident that the potential for radioactive contamination will continue to grow. The purposes of marine environment monitoring around nuclear facilities are to verify that they are functioning as it was designed and to detect the unplanned releases of radioactive contaminants. To provide a sufficient assessment with biological indicators of 60Co and 137Cs, most significant radionuclides in waste effluents released with nuclear power station, the concentration of stable elements in the Sargassum and other algae were surveyed with thermal neutron activation method. The results were followed: 1) The concentration of Mn, As, Zn, and Co were seem to be higher in the sargassum than in other algae. 2) The concentration of Co and Cs were higher in S. thunbergit than in other Sargassum. (author)

  6. Study of trace impurities in heroin by neutron activation analysis

    International Nuclear Information System (INIS)

    Sixty-two heroin samples were analyzed for their contents of 15 trace elements (Au, Ba, Br, Ca, Ce, Co, Cr, Fe, La, Na, Sb, Sc, Sm, Th, and Zn) by neutron activation analysis (NAA). Large variations of elemental concentrations between samples were found to possess statistical significance. Of all the elements calcium was the most abundant element, followed by zinc and sodium. The concentrations of Au, Ce, Co, La, Sb, Sc, Sm, and Th in all the samples were below 1 μg x g-1. Classification of these heroin samples was achieved by the application of hierarchical cluster analysis. The results show that NAA can provide useful information on the origin of the illicit drugs. (author)

  7. Clinical applications of in vivo neutron-activation analysis

    International Nuclear Information System (INIS)

    In vivo neutron activation has opened a new era of both clinical diagnosis and therapy evaluation, and investigation into and modelling of body composition. The techniques are new, but it is already clear that considerable strides can be made in increasing accuracy and precision, increasing the number of elements susceptible to measurement, enhancing uniformity, and reducing the dose required for the measurement. The work presently underway will yield significant data on a variety of environmental contaminants such as Cd. Compositional studies are determining the level of vital constituents such as nitrogen and potassium in both normal subjects and in patients with a variety of metabolic disorders. Therapeutic programs can be assessed while in progress

  8. Extraction and neutron activation analysis of humic substances

    International Nuclear Information System (INIS)

    Methods are described for the isolation of humic substances from a soil sample. The procedures are based on extractions with sodium hydroxide or sodium pyrophosphate. Four of the humic samples were dried and then analyzed by thermal neutron activation analysis. The humic samples along with three standard rocks were irradiated for 15 hours in a flux of approx. 10sup(12)nxcmsup(-2)xssup(-1). Counting was carried out using both a large volume Ge(Li) detector and a high resolution LEP detector. Quantitative analysis was based on the known element concentrations in the standard rocks. The elements determined were Sc, Cr, Fe, Co, As, Se, Br, Mo, Sb, La, Ce, Eu, Hf, Ta, Th and U. Concentrations ranged from 0.02 ppm (La) to 7900 ppm (Fe). (author)

  9. Enhancement of research reactor utilization for neutron activation analysis

    International Nuclear Information System (INIS)

    Analytical Chemistry Division has been utilising NAA for the past 4 decades for trace analysis of a number of materials. Some of the procedures developed recently for the trace element determination of high purity hi-tech and nuclear pure materials, geological, environmental and forensic samples by radiochemical neutron activation analysis (RNAA) are discussed here. Nearly complete characterization of high purity (>4N) As and Ga is possible by the procedures developed which are simple, rapid and elegant and can be used easily for the process samples. It is to be emphasised that though the INAA is simple and being widely followed, the RNAA alone can address the problems of analysis for elements present at ultra trace levels in many matrices. (author)

  10. Semiautomatic exchanger of samples for carry out neutron activation analysis

    International Nuclear Information System (INIS)

    In this paper the design methodology and implementation of a semiautomatic exchanger of samples for the Analysis Laboratory by Neutron Activation of the Reactor department is presented. Taking into account the antecedents, the necessities of improvement are described, as well as the equipment that previously contained the Laboratory. The project of the semiautomatic exchanger of samples was developed at Instituto Nacional de Investigaciones Nucleares, with its own technology to increase independence from commercial equipment. Each element of the semiautomatic exchanger of samples is described both in the design phase as construction. The achieved results are positive and encouraging for the fulfillment of the proposed objective that is to increase the capacity of the Laboratory. (Author)

  11. Recent developments in environmental research using neutron activation analysis

    International Nuclear Information System (INIS)

    In studies of the origin and fates of trace elements, it is advantageous to be able to analyze samples for a wide spectrum of elements with a high sensitivity and accuracy. This condition is best satisfied with instrumental neutron activation analysis (INAA), since it is one of the most sensitive, selective, and reliable multielement analysis techniques available. In spite of these advantages in environmental studies, use of the technique has been generally limited to aerosol and source material analysis. Over the last few years, the trace analysis and radiochemistry group at the Massachusetts Institute of Technology's Nuclear Reactor Laboratory has applied INAA to various environmental samples for methodology development and/or to provide more information on some important environmental processes. Some examples of these studies are provided in this paper

  12. Tracking soil transport to sugarcane industry using neutron activation analysis

    International Nuclear Information System (INIS)

    Soil as mineral impurity in sugarcane loads impacts the Brazilian sugar-ethanol industry with rising production and maintenance costs as well as decreased productivity. The mechanical harvesting of sugarcane was conceived as a technology with potential to increase the raw material quality thereby has been gradually replacing manual harvesting throughout the country. Instrumental neutron activation analysis was applied for determination of soil tracers in order to compare the performance of both harvesting systems in terms of mineral impurities. There were no significant differences in the amount of soil transported to sugarcane industry despite the technological progress aggregated to mechanical harvesting. However, for both harvesting systems there were significant differences on the amount of such mineral impurity between clay and sandy soils. (author)

  13. Artificial Neural Network Characteristic For Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Neutron activation analysis (NAA) is one of analysis methods for identification of elements from material. Irradiated unknown material could be identified by gamma spectrum pattern analysis. The recognition process will be done easily if we have a smart system. One of the smart system choices was artificial neural network (ANN). The gamma spectrum emitted from radioactive nuclide has specific pattern, therefore smart system will try to classify the input data. Firstly, Hp-Ge detector detects gamma radiation from material, then the gamma radiations is counted by multi channel analysis instrument (MCA). The smart system based ANN system was tested to identify 50 material, in which the system has been trained by using one data only for each classifications. The result showed that the ANN appreciates 100% identification capability or has a good performance

  14. Neutron activation analysis of phytotherapic obtained from medicinal plants

    International Nuclear Information System (INIS)

    This paper determines the inorganic constituents in phytotherapic samples for posterior study of the relationship existent among the concentrations of the found elements and the their possible therapeutical effects. The samples of phytotherapic pills (Centella asiatica, Ginkgo biloba and Ginseng) were analysed by using neutron activation analysis (NAA). The As, Br, Ca, Co, Cr, Cs, Fe, K, La, Na, Rb, Sc, Se and Zn samples were determined in the phytotherapics, The Centella asiatica presented the higher concentrations of Br, Co, Cr, Fe, K, La, Na, Rb, Sc, Se and Zn. In the sample of Ginko biloba, higher levels of As and Ca were found, while in the sample ol Ginseng the element As were not detected. The found results have shown the the NAA method is appropriated for analysing this type of materials due to his simplicity, multielemental capacity and quality of the results obtained. (author)

  15. Neutron activation analysis of snow and ice in Antarctica

    International Nuclear Information System (INIS)

    In order to minimize the possible contamination during storing and pre-treatment of such pure samples as ice and snow collected in Antarctica, trace elements in experimental tools such as bottles, beakers, tubings and filters were determined by neutron activation analysis. By using well certified tools, ice and snow samples from Antarctica and high mountains in China and in Japan were analyzed. Relative concentrations of volatile elements such as Zn, Cd, As, Sb or Ag to Al or Fe which are major components in the earth crust were found to be 10 to 1000 times higher than in the ordinary soil for the samples from Antarctica and Mt. Naimonanyi in China. (author) 5 refs.; 7 tabs

  16. Instrumental neutron activation analysis of archaeological ceramics: Progress and challenges

    International Nuclear Information System (INIS)

    Instrumental neutron activation analysis (INAA) has become a widely used technique in the characterization of archaeological ceramics. Early applications, primarily developmental in nature, have been replaced by studies that attempt to place the derived analytical data in a larger archaeological and behavioural context. If archaeology is to increasingly exploit the great potential of INAA to address a broad range of social and cultural issues involving ceramics, greater attention must be paid to the various sources of variation that contribute to the chemical composition of pottery. In addition, as all research takes place within a social context, efforts must be made to increase the communication between archaeologists and other scientists, as this will contribute to the fulfilment of the archaeological research objectives. (author)

  17. Instrumental Neutron Activation Analysis in archaeology interpretation beyond elemental abundance

    International Nuclear Information System (INIS)

    Application of instrumental neutron activation analysis to the study of archaeological ceramics involves the determination of the source or sources used to produce pottery. Groups of relatively homogeneous elemental abundances are shown to be statically distinct from one another often leading to the assesment of what was locally produced and what was imported to a site. These assesment, however are among the most preliminary interpretations. Archaeology is concerned with the reasons for artificial distributions and how and why the distribution varied through time 3 reasons that include the social and political basis of ancient economics and how these responded to other factors, such as ideology. These objectives are addressed through the increasing refinement of compositional groups leading toward greater specificity of attribution. In so doing the role of analytical precision among other considerations groves in importance. This paper illustration some of these considerations with examples from the U.S. southwest, the Maya region of southern mexico, and lower central America

  18. Neutron activation analysis of organohalogens in Chinese human hair

    International Nuclear Information System (INIS)

    To effectively extract organohalogens from human hair, two factors, the extracting time and hair length on the extraction efficiency of organohalogens were studied by neutron activation analysis (NAA) and gas chromatograph-electron capture detector (GC-ECD), respectively. Furthermore, the concentrations of extractable organohalogens (EOX) and extractable persistent organohalogens (EPOX) in hair samples from angioma and control babies were also measured by the established method. The results indicated that the optimal Soxhlet-extraction time for EOX and EPOX in hair was from 8 to 11 hours, and the extraction efficiencies for organochlorine pesticides in hair were in the order of powder >2 mm>5 mm. Also, the mean levels of EOCl and EPOCl in hair of the angioma babies were significantly higher than those in the control babies (PEOClEPOCl<0.05), which implied the possible relationship between the environmental pollution and angioma. (author)

  19. Instrumental neutron activation analysis of fly ash, aerosols and hair

    International Nuclear Information System (INIS)

    Samples of coal, slag, emissions retained on the separating devices, fly ash, aerosols and hair taken in the area of coal-fired power plant were analyzed by means of instrumental neutron activation analysis. 13 to 23 elements were determined in the samples. The data obtained for emissions and aerosols were further evaluated by calculation of enrichment factors, correlation coefficients and by the ratio matching method. The concentrations of elements determined in the hair of the exposed group were compared with data of control and so called ''out control'' groups as well as with recent data found for hair in other countries. It can be seen from the results that arsenic is the most serious pollutant in the area. (author)

  20. Instrumental neutron activation analysis of the hair of metallurgical workers

    International Nuclear Information System (INIS)

    Hair samples were collected from 20 metallurgical workers (10 males and 10 females) and from 59 control subjects (32 males and 27 females), whose jobs do not indicate a specific occupational exposure. The concentrations of ten minor and trace elements (Al, Co, Cu, Fe, Mg, Mn, Sb, Se, V and Zn) were determined by instrumental neutron activation analysis (INAA). The statistical data distributions, the sex and age influences in these elemental concentrations and the average values obtained for the control group were compared with published data. The effect of occupational exposure to the metallic elements was reflected in elemental compositon of hair by significant higher concentration levels of Al, Co, Cu, Fe, Mg, Mn, Sb, V and Zn in the hair of the exposed group, when compared with the control group. (author)

  1. Human hair identification by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Nondestructive neutron activation technique was used to analyze 17 elements (Al, As, Au, Ba, Br, Cl, Cu, Hg, I, K, Mg, Mn, Na, Sb, Sr, V and Zn) in 75 human hair samples in 5 different locations, respectively, from 15 glassware workers. The analytical results were treated further statistically to find the elemental distribution among different human hairs and to identify the individual's hair. The identifying probability of one's hair by the comparison of elemental concentrations is found to be 104-106 times higher from the same person's than from any other person's. The standard deviation of the elemental concentrations of samples taken from 5 different locations of one person is about 5 time smaller than the standard deviation for individual's hair. These data support the possibility of using NAA of hair for human hair identification. (author)

  2. Neutron activation analysis for monitoring northern terrestrial ecosystems

    International Nuclear Information System (INIS)

    New experimental data have been obtained on heavy metal and rare-earth element concentrations in environmental objects, namely pine needles and soils, caused by atmospheric pollution in different regions of the Kola Peninsula. The investigation was performed with the use of epithermal neutron activation analysis at the IBR-2 fast pulsed reactor. The analysis of nearly 40 element distributions in pine needles and soils from the studied geographical points testifies of a strong contamination source - the nickel smelting complex in Monchegorsk. The contamination levels for Ni, Co, Cr, Se, and others are also high and may be hazardous for this region population because some of these elements are carcinogenic. 6 refs., 1 fig., 2 tabs

  3. Elemental analysis of ancient potteries using instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    The provenance studies of archaeological artifacts like potteries, bricks, and coins demands elemental analysis. Instrumental Neutron Activation Analysis (INAA) with high resolution gamma ray spectrometry was used due to its high sensitivity and simultaneous multielement capability. The ancient pottery samples belong to Melchittamur, collected from Department of Ancient History, Tamilnadu, were irradiated in KAMINI reactor, IGCAR, Kalpakkam and counted using PC based Aptec MCA card. The peak areas were obtained using peak-fit PHAST software. The elemental concentrations were calculated using relative method with IAEA RM SL-1 as comparator. The concentrations of elements K, Sc, Cr, Mn, Fe, Co, In, Cs, La, Ce, Sm, Eu, Hf and Th were determined. The % uncertainties are within 1-12% except for Cr, In, Cs and Th

  4. Clinical applications of in vivo neutron-activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Cohn, S.H.

    1982-01-01

    In vivo neutron activation has opened a new era of both clinical diagnosis and therapy evaluation, and investigation into and modelling of body composition. The techniques are new, but it is already clear that considerable strides can be made in increasing accuracy and precision, increasing the number of elements susceptible to measurement, enhancing uniformity, and reducing the dose required for the measurement. The work presently underway will yield significant data on a variety of environmental contaminants such as Cd. Compositional studies are determining the level of vital constituents such as nitrogen and potassium in both normal subjects and in patients with a variety of metabolic disorders. Therapeutic programs can be assessed while in progress.

  5. Multiple scattering Compton camera with neutron activation for material inspection

    International Nuclear Information System (INIS)

    We designed a multiple scattering Compton camera (MSCC) based on a lanthanum bromide (LaBr3:Ce) scintillator to detect neutron-activated prompt gamma-rays for material inspection. The system parameters such as detector thickness and inter-detector distances were optimized on the basis of figure of merit (FOM). The FOM was maximized when the inter-detector distance and detector thickness were 18 cm and 1.5 cm, respectively. Under the optimized conditions, energy spectra and spatial images were obtained to identify various substances, and the results matched well with theoretical data. The probability of multiple Compton scattering was higher than that of conventional Compton scattering at high energies (~MeV), which proved the effectiveness of MSCC to detect prompt gamma-rays. Simulations with realistic conditions showed the feasibility of using the MSCC investigate of materials in field applications

  6. Status Report on the Neutron Activation Analysis Activities in the Philippines

    International Nuclear Information System (INIS)

    The Philippines has a one megawatt open-pool type nuclear research reactor which is presently utilized in the conduct of nuclear research and development activities. The reactor is operated by the Philippine Atomic Research Center, the research arm of the Philippine Atomic Energy Commission. The reactor is presently utilized in the production of some radioisotopes, nuclear physics experiments and neutron activation analysis. For activation analysis the facilities available include the two 2 inch pneumatic tubes and a 2-inch central core dry-pipe. Although the reactor has been operative since 1963 it was only in the latter part of 1966 that a neutron activation analysis group was organized and almost immediately the training of personnel and setting up of a radiochemical laboratory and nucleonic counting assembly were initiated. Today, the counting system include a 100 channel analyzer with a 3 x 3 inch Nal(Tl) crystal

  7. Nitrogen determination in wheat by neutron activation analysis using fast neutron flux from a thermal nuclear reactor

    International Nuclear Information System (INIS)

    This is a study of the technique for the determination of nitrogen and other elements in wheat flour through activation analysis with fast neutrons from a thermal nuclear reactor. The study begins with an introduction about the basis of the analytical methods, the equipment used in activation analysis and a brief description of the neutrons source. In the study are included the experiments carried out in order to determine the flux form in the site of irradiation, the N-13 half life and the interference due to the sample composition. (author)

  8. Using robust statistics to improve neutron activation analysis results

    Energy Technology Data Exchange (ETDEWEB)

    Zahn, Guilherme S.; Genezini, Frederico A.; Ticianelli, Regina B.; Figueiredo, Ana Maria G., E-mail: gzahn@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro do Reator de Pesquisas

    2011-07-01

    Neutron activation analysis (NAA) is an analytical technique where an unknown sample is submitted to a neutron flux in a nuclear reactor, and its elemental composition is calculated by measuring the induced activity produced. By using the relative NAA method, one or more well-characterized samples (usually certified reference materials - CRMs) are irradiated together with the unknown ones, and the concentration of each element is then calculated by comparing the areas of the gamma ray peaks related to that element. When two or more CRMs are used as reference, the concentration of each element can be determined by several different ways, either using more than one gamma ray peak for that element (when available), or using the results obtained in the comparison with each CRM. Therefore, determining the best estimate for the concentration of each element in the sample can be a delicate issue. In this work, samples from three CRMs were irradiated together and the elemental concentration in one of them was calculated using the other two as reference. Two sets of peaks were analyzed for each element: a smaller set containing only the literature-recommended gamma-ray peaks and a larger one containing all peaks related to that element that could be quantified in the gamma-ray spectra; the most recommended transition was also used as a benchmark. The resulting data for each element was then reduced using up to five different statistical approaches: the usual (and not robust) unweighted and weighted means, together with three robust means: the Limitation of Relative Statistical Weight, Normalized Residuals and Rajeval. The resulting concentration values were then compared to the certified value for each element, allowing for discussion on both the performance of each statistical tool and on the best choice of peaks for each element. (author)

  9. Medical application of in vivo neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Cohn, S.H.; Ellis, K.J.; Vartsky, D.; Zanzi, I.; Aloia, J.F.

    1978-01-01

    The clinical usefulness of total body neutron activation analysis (TBNAA) was clearly established at an IAEA panel meeting in Vienna in 1972. It is best demonstrated by the studies involving the measurement of total-body calcium. This measurement provides data useful for the diagnosis and management of metabolic bone disorders. It should be emphasized, however, that while most of the applications to date have involved calcium and phosphorus, the measurement of sodium, chlorine and nitrogen also appear to be useful clinically. Total-body calcium measurements utilizing TBNAA have been used in studies of osteoporosis to establish absolute and relative deficits of calcium in patients with this disease in comparison to a normal contrast population. Changes in total-body calcium (skeletal mass) have also been useful for quantitating the efficacy of various therapies in osteoporosis. Serial measurements over periods of years provide long-term balance data by direct measurement with a higher precision (+- 2%) than is possible by the use of any other technique. In the renal osteodystrophy observed in patients with renal failure, disorders of both calcium and phosphorus, as well as electrolyte disturbances, have been studied. The measure of total-body levels of these elements gives the clinician useful data upon which to design dialysis therapy. The measurement of bone changes in endocrine dysfunction has been studied, particularly in patients with thyroid and parathyroid disorders. In parathyroidectomy, the measurement of total-body calcium, post-operatively, can indicate the degree of bone resorption. Skeletal metabolism and body composition in acromegaly and Cushing's disease have also been investigated by TBNAA. Levels of cadmium in liver and kidney have also been measured in-vivo by prompt-gamma neutron activation and associated with hypertension, emphysema and cigarette smoking.

  10. Quality Assurance and Control in Laboratory using Neutron Activation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Y. S.; Moon, J. H.; Sun, G. M.; Kim, S. H.; Baek, S. Y.; Lim, J. M.; Kim, H. R

    2007-01-15

    In accordance with the increment of international trade associated with the worldwide globalization, the importance of quality assurance and control for the commodity produced from one's own country has been stressed. ISO (International Organization for Standards) defines quality control as 'the operational techniques and activities that are used to fulfill the requirements for quality'. Since 1996, the HANARO research reactor in the Korea Atomic Energy Research Institute has been operated thereafter initial critical operation on April 1995. Neutron activation analysis system and applied techniques which is one of a nuclear analytical technologies using reactor neutrons has been developed for user's supporting and the establishment of the quality system for a measurement and analysis, testing and inspection was implemented successfully. On the basis of the qualified NAA system, the test and measurement of more than 1500 samples which is requested from 30 organizations including industrial companies, universities and institutes carried out in NAA laboratory annually. Moreover, as the goal of mutual recognition agreement (MRA) which can be removed a technical barrier in international trade, the objectivity and the confidence of analytical quality in NAA laboratory became established through the installation of international accreditation system by implementing analytical quality system in accordance with international standards in 2001. The aim of the report was to summarize the technical management of introduction, methods and the results for a quality control and assurance which should be performed in NAA technique using the HANARO research reactor. The report will help building up effective quality control strategy in the future.

  11. Medical application of in vivo neutron activation analysis

    International Nuclear Information System (INIS)

    The clinical usefulness of total body neutron activation analysis (TBNAA) was clearly established at an IAEA panel meeting in Vienna in 1972. It is best demonstrated by the studies involving the measurement of total-body calcium. This measurement provides data useful for the diagnosis and management of metabolic bone disorders. It should be emphasized, however, that while most of the applications to date have involved calcium and phosphorus, the measurement of sodium, chlorine and nitrogen also appear to be useful clinically. Total-body calcium measurements utilizing TBNAA have been used in studies of osteoporosis to establish absolute and relative deficits of calcium in patients with this disease in comparison to a normal contrast population. Changes in total-body calcium (skeletal mass) have also been useful for quantitating the efficacy of various therapies in osteoporosis. Serial measurements over periods of years provide long-term balance data by direct measurement with a higher precision (+- 2%) than is possible by the use of any other technique. In the renal osteodystrophy observed in patients with renal failure, disorders of both calcium and phosphorus, as well as electrolyte disturbances, have been studied. The measure of total-body levels of these elements gives the clinician useful data upon which to design dialysis therapy. The measurement of bone changes in endocrine dysfunction has been studied, particularly in patients with thyroid and parathyroid disorders. In parathyroidectomy, the measurement of total-body calcium, post-operatively, can indicate the degree of bone resorption. Skeletal metabolism and body composition in acromegaly and Cushing's disease have also been investigated by TBNAA. Levels of cadmium in liver and kidney have also been measured in-vivo by prompt-gamma neutron activation and associated with hypertension, emphysema and cigarette smoking

  12. Using robust statistics to improve neutron activation analysis results

    International Nuclear Information System (INIS)

    Neutron activation analysis (NAA) is an analytical technique where an unknown sample is submitted to a neutron flux in a nuclear reactor, and its elemental composition is calculated by measuring the induced activity produced. By using the relative NAA method, one or more well-characterized samples (usually certified reference materials - CRMs) are irradiated together with the unknown ones, and the concentration of each element is then calculated by comparing the areas of the gamma ray peaks related to that element. When two or more CRMs are used as reference, the concentration of each element can be determined by several different ways, either using more than one gamma ray peak for that element (when available), or using the results obtained in the comparison with each CRM. Therefore, determining the best estimate for the concentration of each element in the sample can be a delicate issue. In this work, samples from three CRMs were irradiated together and the elemental concentration in one of them was calculated using the other two as reference. Two sets of peaks were analyzed for each element: a smaller set containing only the literature-recommended gamma-ray peaks and a larger one containing all peaks related to that element that could be quantified in the gamma-ray spectra; the most recommended transition was also used as a benchmark. The resulting data for each element was then reduced using up to five different statistical approaches: the usual (and not robust) unweighted and weighted means, together with three robust means: the Limitation of Relative Statistical Weight, Normalized Residuals and Rajeval. The resulting concentration values were then compared to the certified value for each element, allowing for discussion on both the performance of each statistical tool and on the best choice of peaks for each element. (author)

  13. Mosses as biomonitors to study the atmospheric deposition of heavy metals over the territory of Slovakia

    International Nuclear Information System (INIS)

    In regional trace element studies it is advantageous to determine as many elements as possible in order to better distinguish between different source categories. In the present work the moss bio-monitoring technique and the combination of two analytical techniques - epithermal neutron activation analysis (ENAA) and flame atomic absorption spectrometry (AAS) - were applied to elucidate these problems. The total concentrations of 44 individual elements were determined in 86 samples of mosses. The mean, median, standard deviation and range values was determined for each elements. The use of terrestrial mosses as bio monitors is a well-established technique in Europe Comparison with the current median level in Norway shows strong pollution of the examined areas of Slovakia with the most of heavy metals. Strongly elevated Pb values with compare even South Ural Maintains is evident. The Cd value is 1.5 to 9 times higher than in other Europeans regions, only concentration of Zn are approximately equally. The most important feature of the sampling is that it correlates with the European Moss-Survey-2000, and the results obtained will be incorporated in the Atlas of Heavy Metal Atmospheric Deposition in Europe. (authors)

  14. Tables for simplifying calculations of activities produced by thermal neutrons

    Science.gov (United States)

    Senftle, F.E.; Champion, W.R.

    1954-01-01

    The method of calculation described is useful for the types of work of which examples are given. It is also useful in making rapid comparison of the activities that might be expected from several different elements. For instance, suppose it is desired to know which of the three elements, cobalt, nickel, or vanadium is, under similar conditions, activated to the greatest extent by thermal neutrons. If reference is made to a cross-section table only, the values may be misleading unless properly interpreted by a suitable comparison of half-lives and abundances. In this table all the variables have been combined and the desired information can be obtained directly from the values of A 3??, the activity produced per gram per second of irradiation, under the stated conditions. Hence, it is easily seen that, under similar circumstances of irradiation, vanadium is most easily activated even though the cross section of one of the cobalt isotopes is nearly five times that of vanadium and the cross section of one of the nickel isotopes is three times that of vanadium. ?? 1954 Societa?? Italiana di Fisica.

  15. Implementation of neutron activation analysis in the neutron multiplier CS-ISCTN (first part)

    International Nuclear Information System (INIS)

    The detection limit of 32 elements are determined after experimental evaluation of the neutron flux components in the irradiation position of the neutron multiplier CS-ISCTN. The control of the thermal flux was carry up, comparing the experimental results obtained through three convention used determination of the reaction rate, with the theoretical obtained before

  16. Active detection of shielded SNM with 60-keV neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Hagmann, C; Dietrich, D; Hall, J; Kerr, P; Nakae, L; Newby, R; Rowland, M; Snyderman, N; Stoeffl, W

    2008-07-08

    Fissile materials, e.g. {sup 235}U and {sup 239}Pu, can be detected non-invasively by active neutron interrogation. A unique characteristic of fissile material exposed to neutrons is the prompt emission of high-energy (fast) fission neutrons. One promising mode of operation subjects the object to a beam of medium-energy (epithermal) neutrons, generated by a proton beam impinging on a Li target. The emergence of fast secondary neutrons then clearly indicates the presence of fissile material. Our interrogation system comprises a low-dose 60-keV neutron generator (5 x 10{sup 6}/s), and a 1 m{sup 2} array of scintillators for fast neutron detection. Preliminary experimental results demonstrate the detectability of small quantities (370 g) of HEU shielded by steel (200 g/cm{sup 2}) or plywood (30 g/cm{sup 2}), with a typical measurement time of 1 min.

  17. Non-destructive assay of fissile materials through active neutron interrogation technique using pulsed neutron (plasma focus) device

    International Nuclear Information System (INIS)

    Pulsed neutrons emitted from a plasma focus (PF) device have been used for the first time for the non-destructive assay of 235U content in different chemical forms (oxide and metal). The PF device generates (1.2±0.3)×109 D–D fusion neutrons per shot with a pulse width of 46±5 ns. The method involves the measurement of delayed neutrons from an irradiated sample 50 ms after exposure to the neutron pulse for a time of about 100 s in the multichannel scaling (MCS) mode. The calibration of the active interrogation delayed neutron counter (AIDNEC) system was carried out by irradiating U3O8 samples of varying amounts (0.1–40 g) containing enriched 235U (14.8%) in the device. The delayed neutrons were monitored using a bank of six 3He detectors. The sensitivity of the system was found to be about 100 counts/s/g over the accumulation time of 25 s per neutron pulse of ∼109. The detection limit of the system is estimated to be 18 mg of 235U. The system can be suitably modified for applications toward non-destructive assay of fissile content in waste packets. -- Highlights: ► Plasma focus device has been used for the first time for non-destructive assay of 235U. ► Delayed neutron counting in the multichannel scaling mode is used for the determination of 235U. ► The total time taken for the measurement is about 100 s. ► The detection limit of the system is estimated to be 18 mg of 235U

  18. Non-destructive assay of fissile materials through active neutron interrogation technique using pulsed neutron (plasma focus) device

    Energy Technology Data Exchange (ETDEWEB)

    Tomar, B.S., E-mail: bstomar@barc.gov.in [Radiochemistry and Isotope Group, Bhabha Atomic Research Centre, Mumbai 400085 (India); Kaushik, T.C.; Andola, Sanjay; Ramniranjan,; Rout, R.K. [Multidisciplinary Research Group, Bhabha Atomic Research Centre, Mumbai 400085 (India); Kumar, Ashwani; Paranjape, D.B.; Kumar, Pradeep; Ramakumar, K.L. [Radiochemistry and Isotope Group, Bhabha Atomic Research Centre, Mumbai 400085 (India); Gupta, S.C.; Sinha, R.K. [Multidisciplinary Research Group, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2013-03-01

    Pulsed neutrons emitted from a plasma focus (PF) device have been used for the first time for the non-destructive assay of {sup 235}U content in different chemical forms (oxide and metal). The PF device generates (1.2±0.3)×10{sup 9} D–D fusion neutrons per shot with a pulse width of 46±5 ns. The method involves the measurement of delayed neutrons from an irradiated sample 50 ms after exposure to the neutron pulse for a time of about 100 s in the multichannel scaling (MCS) mode. The calibration of the active interrogation delayed neutron counter (AIDNEC) system was carried out by irradiating U{sub 3}O{sub 8} samples of varying amounts (0.1–40 g) containing enriched {sup 235}U (14.8%) in the device. The delayed neutrons were monitored using a bank of six {sup 3}He detectors. The sensitivity of the system was found to be about 100 counts/s/g over the accumulation time of 25 s per neutron pulse of ∼10{sup 9}. The detection limit of the system is estimated to be 18 mg of {sup 235}U. The system can be suitably modified for applications toward non-destructive assay of fissile content in waste packets. -- Highlights: ► Plasma focus device has been used for the first time for non-destructive assay of {sup 235}U. ► Delayed neutron counting in the multichannel scaling mode is used for the determination of {sup 235}U. ► The total time taken for the measurement is about 100 s. ► The detection limit of the system is estimated to be 18 mg of {sup 235}U.

  19. Study on the methods for analysis of the chemical poison in canister by neutron activity

    International Nuclear Information System (INIS)

    The method that is used to analyse the poison gases in canister by neutron activity is proposed. Through theory analysis and experimental measurement, the feasibility for analysis of the poison gases in a canister by neutron activity has been demonstrated, and it is proved that the method itself do not result in radioactive problem to use again the canister. (authors)

  20. Instrumental neutron activation analysis of carbonatites from Panda Hill and Oldoinyo-Lengai, Tanzania

    International Nuclear Information System (INIS)

    Twenty nine (major and trace) elements including nine rare earth elements (REE) in African carbonatite samples were determined by instrumental neutron activation analysis (INAA). The geochemical behavior of trace elements in carbonatites, especially REE pattern (chondrite normalized), and the efficiency of neutron activation analysis compared to other methods are discussed in this study. (author)

  1. Application of neutron activation analysis system in Xi'an pulsed reactor

    CERN Document Server

    Zhang Wen Shou; Yu Qi

    2002-01-01

    Neutron Activation Analysis System in Xi'an Pulsed Reactor is consist of rabbit fast radiation system and experiment measurement system. The functions of neutron activation analysis are introduced. Based on the radiation system. A set of automatic data handling and experiment simulating system are built. The reliability of data handling and experiment simulating system had been verified by experiment

  2. Determination of gold in some Myanmar indigenous medicines by neutron activation analysis

    International Nuclear Information System (INIS)

    Gold has been determined in two Myanmar indigenous medicines TMF 14 (Devaauthada), TMF 15 (Shwe Thwe Say) by neutron activation analysis using an Am(Be) radionuclide neutron source. The activity of 411 keV of the 198Au has been measured. (author). 2 refs., 1 fig., 1 tab

  3. Use of a 14 MeV neutron generator for activation analysis

    International Nuclear Information System (INIS)

    An overview of applications of the IPEN 14 MeV neutron generator is given. The generator was in active use, for neutron activation analysis, until middle of 1991 when a major breakdown caused serious damage to the vacuum system. (author)

  4. Atmospheric pollution biomonitoring of the Sao Paulo metropolitan region using epiphytic lichens

    International Nuclear Information System (INIS)

    Due to the increasing problems of atmospheric pollution in the Sao Paulo metropolitan region that affect the environment and human health the application of biomonitoring methodologies using cosmopolite organisms has now become relevant. Biomonitoring is a method to evaluate the response of live organisms to pollution. This method offers advantages such as reduced costs, efficient monitoring of large geographic areas and accumulated pollutants over a large period in which low concentrations of chemicals elements in the environment can be evaluated. In the present study, neutron activation analysis method was applied to determine elements accumulated in Canoparmelia texana lichenized fungi. Samples were collected in two distinct areas: Carlos Botelho (PECB) and Intervales (PEI) State Parks that are considered as non-polluted areas and that belong to the Atlantic Forest - SP ecosystem; and Sao Paulo city metropolitan region in sites near automatic monitoring stations of the Environmental Protection Agency of the State of Sao Paulo (CETESB). The lichens collected from the bark of the trees were properly treated, and irradiated with neutrons from IEA-R1 nuclear reactor along with synthetic standards of elements. The precision and the accuracy of the results were evaluated by the analyses of IAEA-336 LICHEN and Mixed Polish Herbs (INCT -MPH-2) certified reference materials. The results obtained for these materials were in accordance with the certified values and presented good precision with variation coefficients ranging from 0.9 to 14.6%. Results obtained for lichens showed that elements As, Co, Cr, Cs, La, Mo, Sb, Sc, Se and U are present at ng g-1 levels, Ba, Br, Cl, Fe, K, Mn, Na, Rb and Zn at μg g-1 and Ca at mg g-1. By applying cluster and discriminant analyses to the results for the lichen samples from areas with different levels of pollution, the sampling sites were grouped according to their chemical similarities and their elemental composition. It was also

  5. Measurement of residual 60Co activity induced by atomic-bomb neutrons in Nagasaki and background contribution by environmental neutrons

    International Nuclear Information System (INIS)

    Residual 60Co activity in five steel samples induced by neutrons from the Nagasaki atomic bomb has been measured within about 1000 m from the hypocenter. The chemical separation of cobalt and nickel from steel samples was performed, and cobalt-enriched samples were prepared for all samples. Gamma-ray measurements were carried out with a low-background well-type germanium detector. The gamma-ray spectra for five samples were compared with the spectrum of a control sample to ensure that the observed 60Co was actually induced by A-bomb neutrons. The activation of cobalt by environmental neutrons was also investigated. It has been shown that the present 60Co data are consistent with earlier Hashizume's data. (author)

  6. Measurement of residual 60Co activity induced by atomic-bomb neutrons in Nagasaki and background contribution by environmental neutrons.

    Science.gov (United States)

    Shizuma, Kiyoshi; Endo, Satoru; Hoshi, Masaharu; Takada, Jun; Iwatani, Kazuo; Hasai, Hiromi; Oka, Takamitsu; Shimazaki, Tatsuya; Okumura, Yutaka; Fujita, Shoichiro; Watanabe, Tadaaki; Imanaka, Tetsuji

    2002-12-01

    Residual 60Co activity in five steel samples induced by neutrons from the Nagasaki atomic bomb has been measured within about 1000 m from the hypocenter. The chemical separation of cobalt and nickel from steel samples was performed, and cobalt-enriched samples were prepared for all samples. Gamma-ray measurements were carried out with a low-background well-type germanium detector. The gamma-ray spectra for five samples were compared with the spectrum of a control sample to ensure that the observed 60Co was actually induced by A-bomb neutrons. The activation of cobalt by environmental neutrons was also investigated. It has been shown that the present 60Co data are consistent with earlier Hashizume's data. PMID:12674203

  7. Calibration of activation detectors in a monoenergetic neutron beam. Contribution to criticality dosimetry

    International Nuclear Information System (INIS)

    Activation detectors have been calibrated for critical dosimetry applications. Measurements are made using a monoenergetic neutron flux. 14 MeV neutrons obtained par (D-T) reaction are produced by 150 kV accelerator. Neutron flux determined by different methods leads us to obtain an accuracy better than 6%. The present dosimetric system (Activation Neutron Spectrometer - SNAC) gives few informations in the (10 keV - 2 MeV) energetic range. The system has been improved and modified so that SNAC detectors must be read out by gamma spectrometer

  8. Neutron activation analysis challenges. Problems and applications in biomedical and other areas

    International Nuclear Information System (INIS)

    Developments in neutron activation analysis in its various modes for trace element determination are described with reference to reactor and other neutron sources, competing methods, tomography and detection systems. A selected number of areas of application are highlighted which provide challenges into the next millennium and to which a useful and in some cases a unique contribution can be made. The role that neutron activation analysis can play in decommissioning, landmine detection, boron neutron capture therapy, Alzheimer's disease, diabetes mellitus, the complex mechanisms of initiation and termination of feeding and obesity as well as in scar formation and the requirements for artificial skin are presented. (author)

  9. Neutron activation analysis challenges: Problems and applications in biomedical and other areas

    International Nuclear Information System (INIS)

    Developments in neutron activation analysis in its various modes for trace element determination are described with reference to reactor and other neutron sources, competing methods, tomography and detection systems. A selected number of areas of applications are highlighted which provide challenges into the next millennium and to which a useful and in some cases a unique contribution can be made. The role that neutron activation analysis can play in decommissioning, land mine detection, born neutron capture therapy, Alzheimer disease, diabetes mellitus, the complex mechanisms of initiation and termination of feeding and obesity as well as in scar formation and the requirements for artificial skin are presented. (author)

  10. Quantitative analysis of silicates by instrumental epithermal neutron activation using (n,p) reactions

    International Nuclear Information System (INIS)

    Instrumental epithermal neutron activation (IENA) involves the use of a neutron filter to screen out the thermal portion of the reactor neutron energy spectrum. Both Cd and B are efficient neutron filters. The principal advantage of epithermal over conventional thermal neutron activation for elemental analysis of geological materials is that the most common rock forming elements, which activate strongly with thermal neutrons (Na, Al, P, K, Fe, and Sc), have their activities suppressed, relative to elements which have cross-sectional resonances in the epithermal energy region. One-gram samples of various silicate standard reference materials were encapsulated in polyethylene vials and irradiated in the Los Alamos Omega West Reactor epithermal facility. Only six elements (F, Si, Na, Fe, Ni, and Ti) were successfully determined in geological matrices via (n,p) reactions. The single standard deviations among the measurements were less than 10% in all cases. The production ratio of (n,p) to (n,γ) and (n,p) to (n,α) interfering reactions are included for silicate materials having Mason's average crustal abundance of elements. Epithermal activation via (n,p) reactions provides an alternative method for the determination of Fe, Al, Na, Ni, and F. The preferred techniques are probably thermal neutron activation for the first three elements, atomic absorption for Ni, and ion selective electrode for F.Titanium and Si can be measured much more sensitively using the (n,p) reaction than by thermal neutron activation. 4 tables

  11. Current status of neutron source and activity in Korea

    International Nuclear Information System (INIS)

    In Korea, the neutron beam experiments had been carried out by operating three units of double axis neutron spectrometers for the study of condensed matter physics and material science. TRIGA MK-II and MK-III were commenced to provide neutron for neutron physicists since 1962 and 1972 respectively, however neutron intensity of these reactors was low (1013 n/cm2·s) that main study had been limited to those which do not require high resolution experiment and studies of structure analysis. Hanaro, new, research reactor which started operation from February, 1995 with 30 MWt and high intensity of neutron (5 x 1014 n/ cm2·s), has solved the limitation of research boundary so that new powerful instruments such as HRPD, FCD, SANS, PNS, NRF, HRTAS, and Reflectometer are being installed to be in service to following schedule; NRF, HRPD, FCD from 1998, SANS from 1999, PNS, HRTAS from 2000

  12. The IAEA Collaborating Centre for Neutron Activation Based Methodologies of Research Reactors

    International Nuclear Information System (INIS)

    The Reactor Institute Delft was inaugurated in May 2009 as a new IAEA Collaborating Centre for Neutron Activation Based Methodologies of Research Reactors. The collaboration involves education, research and development in (i) Production of reactor-produced, no-carrier added radioisotopes of high specific activity via neutron activation; (ii) Neutron activation analysis with emphasis on automation as well as analysis of large samples, and radiotracer techniques; and, as a cross-cutting activity, (iii) Quality assurance and management in research and application of research reactor based techniques and in research reactor operations. (author)

  13. Fusion-neutron-yield, activation measurements at the Z accelerator: Design, analysis, and sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, K. D., E-mail: kdhahn@sandia.gov; Ruiz, C. L.; Fehl, D. L.; Chandler, G. A.; Knapp, P. F.; Smelser, R. M.; Torres, J. A. [Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87123 (United States); Cooper, G. W.; Nelson, A. J. [Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131 (United States); Leeper, R. J. [Los Alamos National Laboratories, Plasma Physics Group, Los Alamos, New Mexico 87545 (United States)

    2014-04-15

    We present a general methodology to determine the diagnostic sensitivity that is directly applicable to neutron-activation diagnostics fielded on a wide variety of neutron-producing experiments, which include inertial-confinement fusion (ICF), dense plasma focus, and ion beam-driven concepts. This approach includes a combination of several effects: (1) non-isotropic neutron emission; (2) the 1/r{sup 2} decrease in neutron fluence in the activation material; (3) the spatially distributed neutron scattering, attenuation, and energy losses due to the fielding environment and activation material itself; and (4) temporally varying neutron emission. As an example, we describe the copper-activation diagnostic used to measure secondary deuterium-tritium fusion-neutron yields on ICF experiments conducted on the pulsed-power Z Accelerator at Sandia National Laboratories. Using this methodology along with results from absolute calibrations and Monte Carlo simulations, we find that for the diagnostic configuration on Z, the diagnostic sensitivity is 0.037% ± 17% counts/neutron per cm{sup 2} and is ∼ 40% less sensitive than it would be in an ideal geometry due to neutron attenuation, scattering, and energy-loss effects.

  14. Neutron yield and induced activity in LBE target by protons

    International Nuclear Information System (INIS)

    Neutron emission cross sections, total neutron yield, angle integrated neutron energy distributions and production of various radioisotopes as primary products from proton induced reactions on thick lead-bismuth-eutectic (LBS) target have been estimated using the codes ALICE91 and EMPIRE 2.18. In the absence of measured data these values can be accepted for shielding and radiation safety design in facilities where intermediate energy proton beams are employed for logistic studies involving spallation reactions. (author)

  15. CIUDENs Pilot Project for CO2 Biomonitoring Tools (PISCO2)

    Science.gov (United States)

    García, D.; Bruno, J.; Credoz, A.; Grandia, F.; Fuentes, J.; Calabuig, E.; Montoto, M.; Ciuden's Co2 Geological Storage Programme

    2011-12-01

    This paper describes CIUDENs Pilot Project for CO2 Biomonitoring Tools (PISCO2) in NW Spain; focusing on the development of biomonitoring of potential CO2 leakages through testing biogeochemical effects of CO2 injection in soils. CIUDEN is a Spanish National foundation created in 2006 dedicated to different projects related to energy and environment. One of the main activities is the construction and operation of various facilities for Research and Development in CCS. The PISCO2 installation consists of 18 cells excavated in the ground and isolated by concrete. Each cell has a 40 m3. The cells will be filled with different soils from various sites in Spain including the Hontomín site in Burgos, where CIUDENs CO2 Storage Technological Development Plant is under construction. The cells are be equipped with systems for (i) controlled CO2 injection at different depths, (ii) control of irrigation and drainage in the unsaturated soil, (iii) sampling of groundwater and gases, and (iv) monitoring of different parameters; such as water content, pH, CO2 flux, microbiological, botanical, and biogeochemical alterations and the chemical composition of water. The main objectives are: the detection of potential diffuse leakage during/after the injection operations; the use of native species as bio-indicators of early leakage; the calibration and optimization of monitoring sensors & methodologies; the optimization of existing multiphase reactive transport models and the comprehension improvement of the biogeochemical processes. The facility is planned to be fully operational in November 2011. Its configuration makes it unique and suitable for international R&D programs. CIUDEN is open for cooperative research projects with institutions all over the world. Results are expected to significantly contribute to the development of new, useful, economical and ecological biomonitoring tools for wide areas. The paper will focus on the presentation of the technical caracteristics and the

  16. Recent applications of neutron activation analysis in Korea

    International Nuclear Information System (INIS)

    There are two purposes in this research; first aim is to promote the use of neutron activation analysis (NAA) as a utilization of nuclear research reactor in the field of air pollution studies through a routine and long-term monitoring. Other is to improve NAA with an experimental simplicity, high accuracy, excellent flexibility with respect to irradiation and counting conditions. For the study on air pollution, airborne particulate matter (APM) for the fine (< 2.5 μm EAD) and coarse particle (2.5-10 μm EAD) fractions were collected using the Gent stacked filter unit low volume sampler and two types of Nuclepore polycarbonate filters. Air samples were collected at two regions (suburban and industrial site of Daejeon city in the Republic of Korea) from January to December 2002. Mass concentration and elemental black carbon of APM were measured and the concentration of 25 elements were determined by Instrumental NAA. Analytical quality control is carried out using three certified reference materials (CRM). The monitoring data were treated statistically to assess air pollution source and source apportionment. The results obtained from this project can be used to investigate source identification and apportionment and its trends, and to establish a more cost-effective method for national air quality management. Preliminary experiment for application of ko-standardization method has been carried out to determine the reactor neutron spectrum parameters, i.e.a and f-values as the main factors of irradiation quality at NAA no.1 irradiation hole on HANARO research reactor, to determine peak detection efficiency for the HP Ge(EG and G ORTEC, GEM 35185) detector for the use in the ko-experiments and to compare the measured concentration results with the certified values of some CRMs applying the experimentally determined ko-parameters. (author)

  17. Recent progress in fast neutron activation cross section data

    International Nuclear Information System (INIS)

    A brief review is given of some significant investigations performed during the past few years in the area of fast neutron activation cross sections that may be relevant for the use of nuclear techniques in the exploration of mineral resources, in process and quality control in industry as well as for general analytical purposes. Differential capture cross sections are considered for the natural elements or isotopes of Fe, Cu, Se, Y, Nb, Cd, In, Gd, W, Os and Au. Some of the data are compared with statistical model calculations. Experimental and evaluated average cross sections for capture and threshold reactions in the spontaneous fission neutron field of 252Cf are reviewed taking into account the elements or isotopes of Mg, Al, Si, S, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Sr, Zr, Nb, Cd, In, Ba, Ta and Au. A summary of recent studies of differential cross sections for threshold reactions comprises data on Al, Si, S, Ti, Fe, Co, Ni, Cu, Zn, Zr, Nb, Ta, W and Au. Besides experimental investigations, evaluations and theoretical model calculations are considered. Cross sections at 14 MeV and in the region around this energy are reviewed for Na, Mg, Al, Cl, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br, Sr, Zr, Nb, In, Er, Yb, Ta, W, Os, Ir, Au and Pb. Particular emphasis is laid on (n,p), (n,2n) and (n,α) reactions. (n,n') reactions are allowed for if the half-life of the metastable state excited permits elemental analyses by common experimental techniques. (orig.)

  18. Recent progress in fast neutron activation cross section data

    International Nuclear Information System (INIS)

    A brief review is given of some significant investigations performed during the past few years in the area of fast neutron activation cross sections that may be relevant for the use of nuclear techniques in the exploration of mineral resources, in process and quality control in industry as well as for general analytical purposes. Differential capture cross sections are considered for the natural elements or isotopes of Fe, Cu, Se, Y, Nb, Cd, In, Gd, W, Os and Au. Some of the data are compared with statistical model calculations. Experimental and evaluated average cross sections for capture and threshold reactions in the spontaneous fission neutron field of 252Cf are reviewed taking into account the elements or isotopes of Mg, Al, Si, S, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Sr, Zr, Nb, Cd, In, Ba, Ta and Au. A summary of recent studies of differential cross sections for threshold reactions comprises data on Al, Si, S, Ti, Fe, Co, Ni, Cu, Zn, Zr, Nb, Ta, W and Au. Besides experimental investigations, evaluations and theoretical model calculations are considered. Cross sections at 14 MeV and in the region around this energy are reviewed for Na, Mg, Al, Cl, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br, Sr, Zr, Nb, In, Er, Yb, Ta, W, Os, Ir, Au and Pb. Particular emphasis is laid on (n,p), (n,2n) and (n,α) reactions. (n,n') reactions are allowed for if the half-life of the metastable state excited permits elemental analyses by common experimental techniques. (author)

  19. Archaeometry Applications of Cold Neutron Based Prompt Gamma Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Prompt Gamma Activation Analysis (PGAA) is based on the detection of prompt gamma radiation following the capture of the neutrons into the atomic nucleus. Since every atomic nucleus emits characteristic prompt gamma radiation, this method is suitable for multielemental (panorama) analysis. The PGAA method can be regarded absolutely non-destructive, because of the relatively low intensity of the beam. In this project, we mainly focus on the research of ancient ceramics. Pottery production is one of the most important crafts of prehistoric communities. In the first task, pottery findings from Neolithic later prehistoric sites in Hungary were investigated with PGAA. Compositions of local sediments, as potential raw material sources were compared with those of pottery. In the second task, pottery fragments from the multiperiodical site of Voers, SW-Hungary were analyzed together with clay from the surrounding areas. In a firing experiment, an attempt to reproduce the ancient production techniques was done. As a third task of the project, PGAA was tested from methodological point of view. The reliability of the method has been occasionally checked through parallel measurements of archaeological samples with INAA and XRF as well. We took part in a proficiency test on a porcelane material, organized by IAEA. (author)

  20. Elemental analysis of airborne particulate by using thermal and epithermal neutron activation

    International Nuclear Information System (INIS)

    Thermal neutron activation analysis was used to determine Al, Br, Ca, Cl, Mn, Na, V, and Ti concentrations, whereas epithermal neutron activation analysis was used to determine Cu, I and Si concentrations. Counting by Compton suppression both in thermal neutron activation and epithermal neutron activation analysis showed the significantly different on detection limit of element compare with normal counting system. It revealed counting by Compton suppression gave better result. The enrichment factor of elements indicated that V and Mn were enriched in several fine particulate samples. Ca, Si and Na were not enriched, whereas Br, I and Cl were enriched in fine airborne particulate or in coarse one. It was found that Cl and Na did not have correlation, while Br and I showed the same enrichment the same enrichment trend and high correlation (0,9). It means that Br and I were from the same pollutant source. It could concluded that the thermal neutron and epithermal neutron activations analysis combined with counting by Compton suppression could enhance sensitivity of analysis of elemental air bone particulate that was very useful in air pollution study. Key words : activation analysis, thermal neutron, epithermal neutron, Compton

  1. Applying bioethical principles to human biomonitoring

    Directory of Open Access Journals (Sweden)

    Harrison Myron

    2008-06-01

    Full Text Available Abstract Bioethical principles are widely used as a normative framework in areas of human research and medical care. In recent years there has been increasing formalization of their use in public health decisions. The "traditional bioethical principles" are applied in this discussion to the important issue human biomonitoring for environmental exposures. They are: (1 Autonomy – Also known as the "respect for humans" principle, people understand their own best interests; (2 Beneficence – "do good" for people; (3 Nonmaleficence – "do no harm"; (4 Justice – fair distribution of benefits and costs (including risks to health across stakeholders. Some of the points made are: (1 There is not a single generic bioethical analysis applicable to the use of human biomonitoring data, each specific use requires a separate deliberation; (2 Using unidentified, population-based biomonitoring information for risk assessment or population surveillance raises fewer bioethical concerns than personally identified biomonitoring information such as employed in health screening; (3 Companies should proactively apply normative bioethical principles when considering the disposition of products and by-products in the environment and humans; (4 There is a need for more engagement by scholars on the bioethical issues raised by the use of biomarkers of exposure; (5 Though our scientific knowledge of biology will continue to increase, there will always be a role for methods or frameworks to resolve substantive disagreements in the meaning of this data that are matters of belief rather than knowledge.

  2. Biomonitoring of Occupational Exposure to Arylonitrile

    Czech Academy of Sciences Publication Activity Database

    Šrám, Radim; Beskid, Olena; Binková, Blanka; Chvátalová, Irena; Rössner st., Pavel; Rössner ml., Pavel

    2001-01-01

    Roč. 37, č. 32 (2001), s. -. ISSN 0893-6692. [EMS. 16.03.2001-21.03.2001, San Diego] Institutional research plan: CEZ:AV0Z5039906 Keywords : biomonitoring * occupational exposure Subject RIV: DN - Health Impact of the Environment Quality

  3. A cyclic neutron activation system using an isotopic neutron source for the measurement of short-lived isotopes

    International Nuclear Information System (INIS)

    The design and construction of an activation analysis system using an isotopic neutron source which allows the measurement of prompt and delay gamma-rays, in conventional activation and cyclic activation modes, is briefly described with emphasis laid on its flexibility, transportability and low cost. Photon spectra obtained from the irradiation of large samples under prompt, delay and cyclic conditions using both NaI(Tl) and Ge(Li) detectors are presented and described with respect to 'in-vivo' neutron activation analysis and the measurement of N, O, Na, P, Cl and Cd. It is pointed out that, despite the attractive possibility of measuring Se in liver, 'in-vivo', by cyclic activation analysis, the system may potentially prove a very useful tool for industrial and other non-medical applications. (author)

  4. Real-Time Active Cosmic Neutron Background Reduction Methods

    Energy Technology Data Exchange (ETDEWEB)

    Mukhopadhyay, Sanjoy; Maurer, Richard; Wolff, Ronald; Mitchell, Stephen; Guss, Paul

    2013-09-01

    Neutron counting using large arrays of pressurized 3He proportional counters from an aerial system or in a maritime environment suffers from the background counts from the primary cosmic neutrons and secondary neutrons caused by cosmic ray-induced mechanisms like spallation and charge-exchange reaction. This paper reports the work performed at the Remote Sensing Laboratory–Andrews (RSL-A) and results obtained when using two different methods to reduce the cosmic neutron background in real time. Both methods used shielding materials with a high concentration (up to 30% by weight) of neutron-absorbing materials, such as natural boron, to remove the low-energy neutron flux from the cosmic background as the first step of the background reduction process. Our first method was to design, prototype, and test an up-looking plastic scintillator (BC-400, manufactured by Saint Gobain Corporation) to tag the cosmic neutrons and then create a logic pulse of a fixed time duration (~120 μs) to block the data taken by the neutron counter (pressurized 3He tubes running in a proportional counter mode). The second method examined the time correlation between the arrival of two successive neutron signals to the counting array and calculated the excess of variance (Feynman variance Y2F)1 in the neutron count distribution from Poisson distribution. The dilution of this variance from cosmic background values ideally would signal the presence of man-made neutrons.2 The first method has been technically successful in tagging the neutrons in the cosmic-ray flux and preventing them from being counted in the 3He tube array by electronic veto—field measurement work shows the efficiency of the electronic veto counter to be about 87%. The second method has successfully derived an empirical relationship between the percentile non-cosmic component in a neutron flux and the Y2F of the measured neutron count distribution. By using shielding materials alone, approximately 55% of the neutron flux

  5. Gamma and Neutron Flux of a Prompt Gamma Neutron Activation Analysis Collimator at the PUSPATI TRIGA Reactor

    International Nuclear Information System (INIS)

    A Prompt Gamma Neutron Activation Analysis (PGNAA) facility is being studied for installation at PUSPATI TRIGA Reactor (RTP) under the Thorium Flagship programme. This work presents the preliminary design of a PGNAA collimator at the RTP. The result of calculations for gamma and neutron flux at various positions of the PGNAA collimator in the RTP beam port 1 by using the computer code MCNPX are presented and discussed. The results indicate the technical feasibility of the installation of PGNAA facility at the RTP and the possibility of enhancing the utilization of the RTP. (author)

  6. Determination of hydrogen in niobium by cold neutron prompt gamma ray activation analysis and neutron incoherent scattering

    Energy Technology Data Exchange (ETDEWEB)

    R.L. Paul; H.H. Cheu-Maya; G.R. Myneni

    2002-11-01

    The presence of trace amounts of hydrogen in niobium is believed to have a detrimental effect on the mechanical and superconducting properties. Unfortunately, few techniques are capable of measuring hydrogen at these levels. We have developed two techniques for measuring hydrogen in materials. Cold neutron prompt gamma-ray activation analysis (PGAA) has proven useful for the determination of hydrogen and other elements in a wide variety of materials. Neutron incoherent scattering (NIS), a complementary tool to PGAA, has been used to measure trace hydrogen in titanium. Both techniques were used to study the effects of vacuum heating and chemical polishing on the hydrogen content of superconducting niobium.

  7. Trace elements in coloured opals using neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    McOrist, G.D.; Smallwood, A. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

    1996-12-31

    Neutron activation analysis (NAA) is a technique particularly suited to analysing opals since it is non-destructive and the silica matrix of opals is not prone to significant activation. It was used to determine the concentration of trace elements in 50 samples of orange, yellow, green, blue and pink opals as well as 18 samples of colourless opals taken from a number of recognised fields in Australia, Peru, Mexico and USA. The results were then evaluated to determine if a relationship existed between trace element content and opal colour. The mean concentration of most of the elements found in orange, yellow and colourless opals were similar with few exceptions. This indicated that, for these samples, colour is not related to the trace elements present. However, the trace element profile of the green, pink and blue opals was found to be significantly different with each colour having a much higher concentration of certain trace elements when compared with all other opals analysed. 7 refs.

  8. Neutron-activation method of monitoring of the environment

    International Nuclear Information System (INIS)

    Full text: Estimation of technogenic influences of the industrial enterprises on an environment, in particular, on ground and underground waters, was carried out by the fragmentary analysis of their element structure. In the report application of neutron-activation analysis (NAA) for monitoring an environment is considered. The total contents of elements was determined by NAA method with use of a reactor such as WWR-SM. Values of factors of correlation (K) are calculated with use of the computer, by special algorithm and reception of numerical values between 30 elements in the samples selected by a traditional technique from more than 600 points in area of activity GMZ-2. The developed technique has allowed to reveal elements indicators of technogenic (As, Ag, Sb, W, Au), mixed (Mo, Ba, Hg) and natural (Sc, Fe, Co, Ni, Rb, Cs, REE, Hf, Th, U) origins. Change of the total contents of elements in underground waters which were selected from observant chinks quarterly within three years is investigated. The technique of definition of forms of a presence of elements in underground and the sewage, based on electrodialysis division of ions with use nuclear (on a basis polyethyleneterephtalate film) filters with a diameter of pores of 0,16x0,2 micrometres is developed

  9. Non-destructive neutron activation analysis of dental porcelain powders

    International Nuclear Information System (INIS)

    Determination of 15 elements in the dental porcelain powders (Vita VMK 68) marketed in Japan was done by means of non-destructive neutron activation analysis. The potassium and sodium contents showed less variations from powder to powder, and the uranium contents varied from a few ppm to 1090 ppm in a wide range. The high contents of uranium (345 - 1090 ppm) were detected in the powders of Enamel, Dentin, Effect, Color and Gum which were used for the superficial parts of a porcelain crown, while the low contents of uranium (1.6 - 2.7 ppm) were detected in those of Opaque and Translucent which were used for the core part and the top of the crown. Cerium and samarium were also detected in each powder in the amounts similar to those of uranium. The main radionuclides present in the porcelain powders were 238U, 235U, 234U, sup(234m)Pa, 234Th, 231Th and 40K. The activities of these nuclides were calculated and discussed. (author)

  10. The influence of an additional filter in epithermal neutron activation analysis

    International Nuclear Information System (INIS)

    Additional filters of tungsten and sodium in different thicknesses have been used in the epithermal neutron activation analysis of geological samples to reduce the interferences caused by resonance neutron capture in these two elements. The results show that a selective reduction of the interfering activities in favor of the activities sought can be obtained. Improvements in terms of detection sensitivity and precision in the γ-spectrometric determinations of Sc, Fe, Co, La, Sm, Eu, Gd, Tb, Yb, Lu, Th and W have been calculated. The possible applications of the filtered epithermal neutron activation analysis (FENA) method to different kinds of samples are also briefly discussed. (author)

  11. Californium-252 neutron activation facility at the Savannah River Laboratory

    International Nuclear Information System (INIS)

    A neutron irradiation facility has been established to develop new analytical methods and for the support of research programs. A major component of this facility is a 252Cf source which provides both fission spectrum and thermal neutrons. (U.S.)

  12. Using tobacco plants as biomonitors of contaminated norm areas

    International Nuclear Information System (INIS)

    One of the largest biomonitoring tasks is the assessing and environment monitoring of radiological wastes produced by mining. Po-210 and Pb-210 are easy to mobilise even in a weak acidic medium and as we know the biological behaviour and accumulation capacity of tobacco, this could be a suitable option for biomonitoring. During our work the Pb-210 and Po-210 concentration values of tobacco parts and soil samples originating from a Hungarian remediated uranium mine site were determined. The source preparation was spontaneous deposition following combined acidic leaching with a Po-209 tracer; the detection was carried out with a semiconductor (‘PIPS’) detector alpha-spectrometer. According to the results for the tobacco plant parts and soil samples, secular equilibrium could be found between the Pb-210 and Po-210 isotopes, and the isotope content of the lower leaves of the tobacco plants was in correlation with the isotope concentration of the soil; therefore, the measurement of the activity concentration is suitable for tracing smaller levels of washing out. The Po-210 activity concentration values of tobacco (average: 15.5 ± 3.6 Bq kg−1) and soil (average: 60.1 ± 15.2 Bq kg−1) samples originating from the area investigated compared with samples from another part of Hungary, Balatonalmádi (tobacco: 12.5 ± 1.0 Bq kg−1, soil: 57.0 ± 4.7 Bq kg−1), do not show significant radionuclide migration. (paper)

  13. Activities of the neutron activation analysis laboratory of the radiochemistry division of IPEN - CNEN/SP

    International Nuclear Information System (INIS)

    Neutron activation analysis (NAA) is one of the relevant applications of nuclear research reactors. Due to the high neutron fluxes available in these reactors, an excellent sensitivity of analysis is attained for many elements. NAA is one of the most sensitive, precise and accurate analytical methods for trace element determination. NAA has been one of the main activities of the Radiochemistry Division of IPEN, since the beginning of the operation of the nuclear reactor IEA-R1. Most of the effort was devoted to research work, aimed to improvements in the method as well as to its applications to several kinds of matrixes (geological, biological, metallic, environmental, forensic). Besides, analytical services were also offered, to the CNEN, to industries, universities, mining companies and research institutes. In the present paper, a review is made of the research work being developed presently at the Radiochesmitry Division of IPEN. A discussion is also made of the planned expansion of the analytical services offered

  14. Neutron Activation Analysis of Lead Halide Pollution Aerosols

    International Nuclear Information System (INIS)

    Iodine, bromine and chlorine have been determined by neutron activation analysis in atmospheric samples of both natural and pollution origin, and a comparison of the two sources provides the basis of a technique described in this paper for determining the composition and possible source of lead halide pollution aerosols. The activation analysis procedure employed consists of reactor neutron irradiation of aqueous samples and comparators for 20 min followed by radiochemical separation of iodine, bromine and chlorine and automatic counting of beta radioactivity from solid silver halide sources. Determination of lead by anodic stripping voltammetry (inverse polarography) consists of deposition of Pb++ from the solution onto a composite paraffin- impregnated graphite and mercury electrode at -1.00 V versus the standard calomel electrode, and then stripping by increasing the potential continuously. A significant question of public health interest in the air chemistry of lead is the source of the lead. Ethyl fluid, a mixture of organic lead, bromine and chlorine compounds, burns to form inorganic lead halide particles with Cl/Pb = 0.34 and Br/Pb = 0.39 by weight. In Cambridge, Massachusetts, analyses of cascade impactor aerosols were compared with similarly collected samples from the unpolluted air of Hawaii. The pollution bromine component ranged from 0.4 to 0.1 or less of the lead concentration, indicating in most cases either automotive lead with a bromine deficiency or a mixture of lead from automotive and other sources. In Fairbanks, Alaska, during winter, atmospheric conditions favour high local concentrations of air pollutants. Aerosols collected by Millipore filters show that pollution chlorine averages very nearly the value predicted from the observed lead and the known composition of ethyl fluid, and the automotive source for both chlorine and lead is strongly indicated. Pollution bromine, however, was less than predicted, and the bromine deficiency was about

  15. Gamma-ray-spectroscopy following high-flux 14-MeV neutron activation

    International Nuclear Information System (INIS)

    The Rotating Target Neutron Source (RTNS-I), a high-intensity source of 14-MeV neutrons at the Lawrence Livermore National Laboratory (LLNL), has been used for applications in activation analysis, inertial-confinement-fusion diagnostic development, and fission decay-heat studies. The fast-neutron flux from the RTNS-I is at least 50 times the maximum fluxes available from typical neutron generators, making these applications possible. Facilities and procedures necessary for gamma-ray spectroscopy of samples irradiated at the RTNS-I were developed

  16. Radiation damage and activation of CdZnTe by intermediate energy neutrons

    International Nuclear Information System (INIS)

    The authors exposed a CdZnTe detector to MeV neutrons from a 252Cf source and found no performance degradation for fluences below 1010 neutrons cm-2. Detector resolution did show significant degradation at higher neutron fluences. There is evidence of room temperature annealing of the radiation effects over time. Activation lines were observed and the responsible isotopes were identified by the energy and half-life of the lines. These radiation damage studies allow evaluation of the robustness of CdZnTe detectors in high neutron and radiation environments

  17. Measurement of activity distributions of (D-T) neutrons in concrete

    International Nuclear Information System (INIS)

    Although abundant data are available on the transport of fission neutrons in bulk media, analogous information on 14 MeV neutrons is very limited. The work reported here is aimed at measuring the spectral quality of (D-T) neutrons in their penetration through concretes of a density 2.4 of g/cm3. The study is of particular significance in determining an optimum shield for a fusion reactor which involves high neutron energy and fluxes. Threshold detectors have been and for specific activity measurements. The measured data is compared with calculations using the code 'ASFIT' and the agreement is found to be satisfactory. (orig.)

  18. Gamma-ray-spectroscopy following high-flux 14-MeV neutron activation

    Energy Technology Data Exchange (ETDEWEB)

    Williams, R.E.

    1981-10-12

    The Rotating Target Neutron Source (RTNS-I), a high-intensity source of 14-MeV neutrons at the Lawrence Livermore National Laboratory (LLNL), has been used for applications in activation analysis, inertial-confinement-fusion diagnostic development, and fission decay-heat studies. The fast-neutron flux from the RTNS-I is at least 50 times the maximum fluxes available from typical neutron generators, making these applications possible. Facilities and procedures necessary for gamma-ray spectroscopy of samples irradiated at the RTNS-I were developed.

  19. Stability evaluation and correction of a pulsed neutron generator prompt gamma activation analysis system

    International Nuclear Information System (INIS)

    Source output stability is important for accurate measurement in prompt gamma neutron activation. This is especially true when measuring low-concentration elements such as in vivo nitrogen (∼2.5 % of body weight). We evaluated the stability of the compact DT neutron generator within an in vivo nitrogen measurement system. Review of gamma event/time patterns and data from an auxiliary detector showed significant variations among repeated phantom runs. Neutron generator instability had a significant effect on measurement precision. The neutron generator used in our system must be monitored for output consistency. Adjustments must be made to measurement results to correct for generator instability. (author)

  20. Error analysis in reactor-core neutron beam density measurements by gold-foil activation

    Energy Technology Data Exchange (ETDEWEB)

    Prokof' ev, Y.A.; Bondarenko, L.N.; Rogok, E.V.; Spivak, P.E.

    1986-09-01

    The most accurate method for neutron density measurements, where the spectrum cut-off energy is appreciably lower than the gold cross-section resonance energy, is by gold-foil activation. The authors show that this method also makes it possible to measure core-beam neutron densities with high accuracy, even though this requires taking into account the gold-activation contribution of epithermal neutrons from 3.10/sup 4 -/b neutron capture at 4.8 eV and inserting the appropriate corrections in the measurement results. The activation method was experimentally used for precision measurement of the reactor-core beam density in the study of the beam neutron half-life. Data are presented which show that the additive error is within the +/-0.5 measurement error.

  1. Search for reaction-in-flight neutrons using thulium activation at the National Ignition Facility

    Science.gov (United States)

    Grim, Gary; Rundberg, Robert; Tonchev, Anton; Fowler, Malcolm; Wilhelmy, Jerry; Archuleta, Tom; Bionta, Richard; Boswell, Mitzi; Gostic, Julie; Griego, Jeff; Knittel, Kenn; Klein, Andi; Moody, Ken; Shaughnessy, Dawn; Wilde, Carl; Yeamans, Charles

    2013-10-01

    We report on measurements of reaction-in-flight (RIF) neutrons at the National Ignition Facility. RIF neutrons are produced in cryogenically layered implision by up-scattered deuterium, or tritium ions that undergo subsequent fusion reactions. The rate of RIF neutron production is proportional to the fuel areal density (| | R) and ion-stopping length in the dense fuel assembly. Thus, RIF neutrons provide information on charge particle stopping in a strongly coupled plasma, where perturbative modeling breaks down. To measure RIF neutrons, a set of thulium activation foils was placed 50 cm from layered cryogenic implosions at the NIF. The reaction 169Tm(n,3n)167Tm has a neutron kinetic energy threshold of 14.96 MeV. We will present results from initial experiments performed during the spring of 2013. Prepared by LANL under Contract DE-AC-52-06-NA25396, TSPA, LA-UR-13-22085.

  2. Fast-Neutron Activation of Long-Lived Nuclides in Natural Pb

    CERN Document Server

    Guiseppe, V E; Fields, N E; Hixon, D

    2012-01-01

    We measured the production of the long-lived nuclides Bi-207, Pb-202, and Hg-194 in a sample of natural Pb due to high-energy neutron interactions using a neutron beam at the Los Alamos Neutron Science Center. The activated sample was counted by a HPGe detector to measure the amount of radioactive nuclides present. These nuclides are critical in understanding potential backgrounds in low background experiments utilizing large amounts of Pb shielding due to cosmogenic neutron interactions in the Pb while residing on the Earth's surface. By scaling the LANSCE neutron flux to a cosmic neutron flux, we measure the sea level cosmic ray production rates of 8.0 +/- 1.3 atoms/kg/day of Hg-194, 120 +/- 25 atoms/kg/day Pb-202, and 0.17 +/- 0.04 atoms/kg/day Bi-207.

  3. Morus nigra plant leaves as biomonitor for elemental air pollution monitoring

    International Nuclear Information System (INIS)

    This study deals with the determination of 36 elements in 120 leaf samples of Morus nigra plant to assess their potential as biomonitor for elemental air pollution monitoring. The elemental quantification was made by employing instrumental neutron activation analysis and atomic absorption spectrometric techniques. The leaf samples were collected in spring, summer and winter seasons from various sites in Islamabad. The reliability of the adopted procedures was established by analyzing the certified reference materials. The calculated enrichment values for all the measured elements in the Morus nigra leave samples during the spring season were minimum as compared to the summer season which in turn were lower than those for the winter season. This gradual increase in enrichment values from spring to winter season can be explained on the basis of extended exposure of leaves to the atmosphere, thus accumulating more metals from the atmosphere leading to higher enrichment values. The lower pollution load index (PLI) values in the spring season could be attributed to less exposure of newly born plant leaves. Higher PLI during summer could probably be due to a series of routine dust storms, resulting in higher concentration of suspended particulate matter. The maximum PLI obtained in the winter season could be related to dry stagnant climatic conditions, having significantly higher concentration of suspended particulate matter, leading to higher accumulation of metals in the plant leaves. The higher metal contents in the leaves of Morus nigra plant as compared to the stem indicate that the absorption of metals from the environment occurs through the leaves. Similar observations have been reported for lead absorption by specific parts of the plants. The results indicated that the adaptation of such reliable and inexpensive procedure using Morus nigra leaves as biomonitor will find a good substitute to the classical approach of collecting aerosol sample with air filter for

  4. Ten year's activity in the field of neutron scattering workshop

    Energy Technology Data Exchange (ETDEWEB)

    Hamaguchi, Yoshikazu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    'Neutron scattering' is in the frame of the 'Utilization of Research Reactor's of the FNCA (Forum for Nuclear Cooperation in Asia) project, which held the workshops from FY 1992. This report is a summary of the results and activities of neutron scattering workshops and sub-workshops since the start in FY 1992. (author)

  5. Studies of neutron cross-sections important for spallation experiments using the activation method

    Czech Academy of Sciences Publication Activity Database

    Vrzalová, Jitka; Chudoba, Petr; Krása, Antonín; Majerle, Mitja; Suchopár, Martin; Svoboda, Ondřej; Wagner, Vladimír

    Vol. 533. Bristol: IOP Publishing Ltd, 2014, 012051. ISSN 1742-6588. [20th International School on Nuclear Physics, Neutron Physics and Applications. Varna (BG), 16.09.2013-22.09.2013] Institutional support: RVO:61389005 Keywords : neutron cross-section * activation method * TALYS Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders

  6. Automatization of the neutron activation analysis method in the nuclear analysis laboratory

    International Nuclear Information System (INIS)

    In the present paper the work done to automatice the Neutron Activation Analysis technic with a neutron generator is described. An interface between an IBM compatible microcomputer and the equipment in use to make this kind of measurement was developed. including the specialized software for this system

  7. First research coordination meeting on reference database for neutron activation analysis. Summary report

    International Nuclear Information System (INIS)

    Potential problems associated with nuclear data for neutron activation analysis were identified, the scope of the work to be undertaken was defined together with its priorities, and tasks were assigned to participants. Data testing and measurements refer to gamma spectrum peak evaluations, detector efficiency calibration, neutron spectrum characteristics and reference materials analysis. (author)

  8. Determination of zinc by substoichiometric thermal neutron activation analysis (Paper No. RA-23)

    International Nuclear Information System (INIS)

    Trace amount of Zn in complex matrices has been determined by substoichiometric thermal neutron activation analysis. The method involves radiochemical separation of 65Zn from neutron irradiated samples employing substoichiometric extraction of Zn(II) with 1,2,3-benzotriazole (1,2,3-BT) into n-heptanol. (author). 1 tab

  9. Possibilities of Controlling Nutritious Wheat Flour by the Method of Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Possibilities of controlling nutritious wheat flour by the method of neutron activation analysis are studied. It is established, that detection of contents of As, Cd, Hg, Cu and Zn in wheat flour is possible using this method and a neutron multiplier. The results of measurements were worked out by polycomparative method. (author)

  10. Measurement of residual 152Eu activity induced by atomic bomb neutrons in Nagasaki and the contribution of environmental neutrons to this activity

    International Nuclear Information System (INIS)

    Residual 152Eu activities induced by neutrons from the Nagasaki atomic bomb were measured for nine mineral samples located up to 1,061 m in the slant range and one control sample at 2,850 m from the hypocenter. A chemical separation to prepare europium-enriched samples was performed for all samples, and gamma ray measurements were carried out with a low background well-type germanium detector. In this paper, the measured specific activities of 152Eu are compared with activation calculations based on the DS86 neutron fluence and the 93Rev one. The calculated-to-measured ratios are also compared with those of 60Co and 36Cl. The present results indicate that the measurements agree to the calculation within a factor of three as observed in the nuclear tests at Nevada. The activation level of environmental neutrons and the detection limit for 152Eu are also discussed. (author)

  11. Measurement of residual 152Eu activity induced by atomic bomb neutrons in Nagasaki and the contribution of environmental neutrons to this activity.

    Science.gov (United States)

    Shizuma, Kiyoshi; Endo, Satoru; Hoshi, Masaharu; Takada, Jun; Ishikawa, Masayori; Iwatani, Kazuo; Hasai, Hiromi; Oka, Takamitsu; Fujita, Shoichiro; Watanabe, Tadaaki; Yamashita, Tomoaki; Imanaka, Tetsuji

    2003-06-01

    Residual 152Eu activities induced by neutrons from the Nagasaki atomic bomb were measured for nine mineral samples located up to 1,061 m in the slant range and one control sample at 2,850 m from the hypocenter. A chemical separation to prepare europium-enriched samples was performed for all samples, and gamma ray measurements were carried out with a low background well-type germanium detector. In this paper, the measured specific activities of 152Eu are compared with activation calculations based on the DS86 neutron fluence and the 93Rev one. The calculated-to-measured ratios are also compared with those of 60Co and 36Cl. The present results indicate that the measurements agree to the calculation within a factor of three as observed in the nuclear tests at Nevada. The activation level of environmental neutrons and the detection limit for 152Eu are also discussed. PMID:13678342

  12. Development of active environmental and personal neutron dosemeters

    International Nuclear Information System (INIS)

    For neutron dosimetry in the radiation environment surrounding nuclear facilities, two types of environmental neutron dosemeters, the high-sensitivity rem counter and the high-sensitivity multi-moderator, the so-called Bonner ball, have been developed and the former is commercially available from Fuji Electric Co. By using these detectors, the cosmic ray neutrons at sea level have been sequentially measured for about 3 y to investigate the time variation of neutron spectrum and ambient dose equivalent influenced by cosmic and terrestrial effects. Our Bonner ball has also been selected as the neutron detector in the International Space Station and has already been used to measure neutrons in the US experimental module. The real time wide-range personal neutron dosemeter which uses two silicon semiconductor detectors has been developed for personal dosimetry and is commercially available from Fuji Electric Co. This dosemeter has good characteristics, fitted to the fluence-to-dose conversion factor in the energy range from thermal energies to several tens of mega-electron-volts and is now widely used in various nuclear facilities. (authors)

  13. Neutron activation analysis: nuclear interference from iron in manganese

    International Nuclear Information System (INIS)

    In the present work, the contribution of iron was verified in the analysis of manganese through the reaction of interference by fast neutron. The irradiation of the samples was accomplished in the channel IC-40 of the rotary rack of the TRIGA MARK I IPR-R1 research reactor, located at Nuclear Technology Development Centre/Brazilian Commission for Nuclear Energy, CDTN/CNEN. In this irradiation device, the average thermal neutron flux is 6.69 x 1011 neutron cm-2 s-1 and fast neutron flux is 7.37 x 1010 neutron cm-2 s-1. Manganese was determined through 56Mn induced by thermal neutron flux according to the reaction 55Mn(n, γ)56Mn. In the analysis of manganese, the contribution of iron was investigated according to the reaction of interference 56Fe(n, p)56Mn produced by the fast neutron. It was verified that the contribution of 1 g of iron is 20 μg of manganese. (author)

  14. In vivo neutron activation analysis of sodium and chlorine in tumor tissue after fast neutron therapy.

    Science.gov (United States)

    Auberger, T; Koester, L; Knopf, K; Weissfloch, L

    1996-01-01

    In 12 patients with recurrences and metastases of different primaries (head and neck cancer, breast cancer, malignant melanoma, and osteosarcoma) who were treated with reactor fission neutrons the photon emission of irradiated tissue was measured after each radiotherapy fraction. Spectral analyses of the decay rates resulted in data for the exchange of sodium (Na) and chlorine (Cl) between the irradiated tissue and the body. About 60% of Na and Cl exchanged rapidly with a turnover half-life of 13 +/- 2 min. New defined mass exchange rates for Na and Cl amount to an average of 0.8 mval/min/kg of soft tissue. At the beginning of radiotherapy the turnover of the electrolytes in tissues with large tumor volumes was about twice that in tissues with small tumor volumes. Depending on the dose, neutron therapy led in all cases to variation in the metabolism. A maximum of Cl exchange and a minimum of Na exchange occurred after 10 Gy of neutrons (group of six previously untreated patients) or after 85 Gy (photon equivalent dose) of combined photon-neutron therapy. A significant increase in non-exchangeable fraction of Na from about 40 to 80% was observed in three tumors after a neutron dose of 10 Gy administered in five fractions correlated with a rapid reduction of tissue within 4 weeks after end of therapy. These results demonstrate for the first time the local response of the electrolyte metabolism to radiotherapy. PMID:8949749

  15. Neutrons flux distribution in a 252Cf irradiation cell for neutron activation analysis

    International Nuclear Information System (INIS)

    A 100 microgram Californium-252 (252Cf) neutron source was embedded in a pure paraffin moderator surrounded by neutron and gamma ray shields to be used as an irradiation cell facility for NAA experiments. The cell is provided with a direct horizontal channel and a Vertical Tangential Irradiation Channel (VTIC) that are parallel to the source axis. The cadmium difference method was used in determining the thermal and epithermal neutron flux distributions along the axis of the (VTIC). For this purpose, 10 pairs of bare and cadmium covered pure gold foils were irradiated at the same positions along the axis of the (VTIC) in two separate runs. The absolute efficiency of the HPGe detector at the gamma ray energy 411.8 keV of 198 Au, was found to be 0.0318 ± 0.0025.The obtained distributions of thermal and epithermal neutron fluxes were tabulated and graphically presented. An evidence for contributions from 252Cf fission by epithermal neutrons was noticed. As an application on this facility the concentration of gold in an ore sample from gold - bearing ivory vein of wady Allaqui (at south west of eastern desert) was determined. It was found to be 612 ± 6 ppm

  16. Determination of oxygen content in steel using activation analysis with 14 MeV neutron

    International Nuclear Information System (INIS)

    In the quantitative analysis of oxygen in steel by fast neutron activation analysis the oxygen content is evaluated from the measured activity of 16N produced. Steel s mples are irradiated in 14 MeV neutron flux. After irradiation the samples are pneumatically transfered to the counting terminal where activity is measured. Oxygen concentrations, are obtained by comparison with standards of specified oxygen content

  17. Optimization in Activation Analysis by Means of Epithermal Neutrons. Determination of Molybdenum in Steel

    International Nuclear Information System (INIS)

    Optimization in activation analysis by means of selective activation with epithermal neutrons is discussed. This method was applied to the determination of molybdenum in a steel alloy without recourse to radiochemical separations. The sensitivity for this determination is estimated to be 10 ppm. With the common form of activation by means of thermal neutrons, the sensitivity would be about one-tenth of this. The sensitivity estimations are based on evaluation of the photo peak ratios of Mo-99/Fe-59

  18. Biomonitoring of the genotoxic potential (micronucleus assay) and detoxifying activity (EROD induction) in the River Dadou (France), using the amphibian Xenopus laevis

    OpenAIRE

    Gauthier, Laury; Tardy, Emmanuelle; Mouchet, Florence; MARTY, Josette

    2004-01-01

    Within the framework of a general survey of the water quality of the river Dadou (Tarn, France), different physicochemical parameters were measured and an inventory of the fish population was made along the water course, around the Rassisse dam.With the aim of monitoring the potential genotoxic effects and the detoxifying activities induced in organisms exposed to the river water, two in vivo bioassays were performed in laboratory experiments, using larvae of the amphibian Xenopus laevis.The ...

  19. Neutron activation analysis: a powerful tool in provenance investigations

    International Nuclear Information System (INIS)

    It is well known that neutron activation analysis (NAA), both instrumental and destructive, allows the simultaneous determination of a number of elements, mostly trace elements, with high levels of precision and accuracy. These peculiar properties of NAA are very useful when applied to provenance studies, i.e. to the identification of the origin of raw materials with which artifacts had been manufactured in ancient times. Data reduction by statistical procedures, especially multivariate analysis techniques, provides a statistical 'fingerprint' of investigated materials, both raw materials and archaeological artifacts, that, upon comparison, allows the identification of the provenance of prime matters used for artifact manufacturing. Thus information on quarries and flows exploitation in the antiquity, on technological raw materials processing, on trade routes and about the circulation of fakes, can be obtained. In the present paper two case studies are reported. The first one deals with the identification of the provenance of clay used to make ceramic materials, mostly bricks and tiles, recovered from the excavation of a Roman 'villa' in Lomello (Roman name Laumellum) and of Roman settlings in Casteggio (Roman name Clastidium). Both sites are located in the Province of Pavia in areas called Lomellina and Oltrepo respectively. The second one investigates the origin of the white marble used to build medieval arks, Carolingian age, located in the church of San Felice, now property of the University of Pavia. Experimental set-up, analytical results and data reduction procedures are presented and discussed. (author)

  20. Present status of neutron activation analysis in environmental research

    International Nuclear Information System (INIS)

    Neutron activation analysis, in spite of its many advantageous features, is less widely used than some alternative trace element techniques, and has been losing ground during the last decade. In the environmental field however there are still many problems which can be solved in a better way by the contribution of NAA. The combination of multi-element capability and high accuracy is of great importance in many studies related to atmospheric trace elements. Also in aquatic studies NAA still has a significant role to play. Applications to soils, sediments, and plant material have so far been limited, but there is a place for further development. The scope of NAA in environmental research may be extended by further use of pre-irradiation separations. NAA is particularly important in the certification of analytical reference materials in the environmental field. In future applications of NAA an appropriate combination with other analytical techniques will often be a requisite for success. The general future of NAA is dependent on the availability of nuclear reactors, radiochemical laboratoties and appropriate competence. 21 references

  1. Intrinsic quality assurance aspects of neutron activation analysis

    International Nuclear Information System (INIS)

    Full text: Neutron activation analysis (NAA) is an extremely valuable tool for the certification of Certified Reference Materials (CRMs) for a number of reasons. First, the method itself has characteristics that inherently provide few sources of error compared to many other analytical techniques. In addition, the intrinsic quality assurance characteristics of the method often allow the analytical values to be internally evaluated and cross checked. For example, most spectroscopic techniques separate the signals of the different excited species (analytes and interferences) by a single parameter, i.e. energy, mass, wavelength, time, etc. NAA can separate the signals of excited species (radionuclides) via two different parameters, energy and time (half-life). The ability to perform gamma ray spectrometry on the same sample after different decay times often provides the capability of verifying the absence of many sources of error such as interferences, incorrect pileup corrections, incorrect dead-time corrections, use of an erroneous half-life, etc. In addition, quantification using multiple gamma rays of the same isotope, and in some cases entirely different isotopes of the same element, can provide a powerful tool to minimize the possibility of errors due to interferences. Finally, counting both samples and standards at multiple geometries can provide insight into the importance of counting geometry effects. This presentation will describe ways to take advantage of some of the unique QA characteristics of Naca to observe and eliminate a number of potential sources of error. (author)

  2. Instrumental neutron activation analysis. A valuable link in chemical metrology

    International Nuclear Information System (INIS)

    A systematic experimental approach to the demonstration of viability of instrumental neutron activation analysis (INAA) in chemical metrology is provided. The practical approach was derived from a complete survey of uncertainty components that affect the INAA measurement process. These uncertainty components were classified by their magnitude and origin and subsequently minimized by appropriate steps in the INAA process. The process was tested with the INAA determination of Cr in SRM 1152A stainless steel; the Cr value is certified at 17.76% with an estimated uncertainty of 0.04% (0.23% relative). The INAA results from this procedure are in agreement with these specifications. Similar procedures have been applied to INAA multi-element determinations in a high temperature alloy. Agreement with available consensus values was demonstrated in the alloy. The guidelines on the determination of uncertainty were fully met, providing through INAA a valuable independent non-destructive tool in chemical measurements of metrological value such as required in the CCQM key comparisons. (author)

  3. Essential trace elements in edible mushrooms by Neutron Activation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Moura, Patricia L.C.; Maihara, Vera A.; Castro, Lilian P. de [Instituto de Pesquisa e Energetica e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: patricialandim@ig.com.br; vmaihara@ipen.br; lilian.Pavanelli@terra.com.br; Figueira, Rubens C.L. [Universidade Cruzeiro do Sul, Sao Paulo, SP (Brazil)]. E-mail: figueiraru@yahoo.com.br

    2007-07-01

    Mushrooms are excellent nutritional sources since they provide proteins, fibers and mineral, such as K, P, Fe. They have also been the focus of medical research. In Brazil mushrooms are not consumed in large quantities by the general population since people know little about the nutritional and medicinal benefits that mushrooms offer. Hence, this study intends to contribute to a better understanding of the essential element content in edible mushrooms, which are currently commercialized in Sao Paulo state. Br Fe, K, Na and Zn concentrations were determined by Instrumental Neutron Activation Analysis in the following mushroom species: Shitake (Lentinus edodes), Shimeji (Pleurotus ssp), Paris Champignon (Agaricus bisporus), Hiratake ( Pleurotus ssp) and Eringue (Pleurotus Eryngu. The mushroom samples were acquired from commercial establishments in the city of Sao Paulo and directly from the producers. Essential element contents in mushrooms varied between Br 0.03 to 4.1 mg/kg; Fe 20 to 267 mg/kg; K 1.2 to 5.3 g/kg, Na 10 to 582 mg/kg and Zn 60 to 120 mg/kg. The results confirm that mushrooms can be considered a good source of K, Fe and Zn. The low Na level is a good nutritional benefit for the consumer. (author)

  4. Study of nutritional supplements using neutron activation analysis

    International Nuclear Information System (INIS)

    The increasing consumption of nutritional supplements among the people mainly aiming at the replacement of nutrients and minerals in the organism has led the commercialization of a great number of brands of these products. Consequently the quality control of these products is of great interest to verify if their element contents agree the values presented in labels or in the instructions for their uses. In this study the elements Ca, Co, Cr, Cu, Fe, K, Na, Se and Zn were analyzed in multimineral supplements and vitamins samples using neutron activation analysis method. The results obtained compared with the values of the labels of nutritional supplements presented good agreement. For quality control of the analytical data, certified reference materials NIST 1400 Bone Ash and NIST 1633b Coal Fly Ash provided by National Institute of Standards and Technology were analysed. Accuracy and precision of the results were evaluated and Z score values obtained were lower than 2 indicating that the data found are within the certified values at 95% of significance level. (author)

  5. Neutron activation analysis and provenance study of Tupiguarani Tradition pottery

    International Nuclear Information System (INIS)

    Archaeology can fill the gap between ancient population and modern society elucidating the evidences found in archaeological sites. The fingerprint identified, that is the chemical composition of the ceramics, can help understanding this connection between the past and the present. The Tupiguarani Tradition vestiges found by archaeologists will be a way to know about the last two millennia of the Brazilian prehistory. This archaeological site is located along the coast of the Brazilian State of Espirito Santo, where the main evidence is a pretty ceramic with the occurrence of plastic and painted decoration. When the Portuguese settlers arrived in this region, in sixteenth century, several Missoes Jesuiticas (Jesuitical Missions) were built along the Brazilian coast. In spite of living within the Mission and been catechized, the Indians kept on producing traditional handicraft, as the decorated ceramic, however, they introduced European elements to the decoration. During the research expeditions made to the archaeological site of the Tupiguarani Tradition, many sherds were found. The identification and classification of ceramics through a multielemental chemistry analysis will be used to determine if they have the same origin. This paper shows the first elemental concentration results of the sherds collected from archaeological site determined at CDTN/CNEN, Belo Horizonte, Minas Gerais, using the TRIGA Mark I IPR-R1 nuclear reactor, applying the neutron activation technique, k0-method. (author)

  6. Residual Chromium in Leather by Instrumental Neutron Activation Analysis

    Directory of Open Access Journals (Sweden)

    S. Okoh

    2012-01-01

    Full Text Available Problem statement: Most tanning processes employ the use of chromium sulphate. For chromium tanned leather, finished products may contain high amount of residual chromium. This may pose some health hazards, since chromium is known to be toxic at elevated concentration. This justifies the need for the study. Approach: Various samples of leather were collected from a tannery, a leather crafts market, a leather dump site and from local tanners all in Kano, Nigeria in 2009. The samples were irradiated for 6 h in the inner site of the Nigerian Research Reactor (NIRR-1 at a flux of 5×1011 ncm-2 sec-1. Results: After evaluating the spectrum, the mean results for chromium in the samples were determined as 2.33±0.3, 2.23±0.3 and 2.93±0.4% for samples from the tannery, leather crafts market and leather dump sites respectively. Chromium concentration in samples collected from local tanners who use tannins from Acacia nilotica as tanning agent was below the detection limit of Instrumental Neutron Activation Analysis (INAA technique used in the study. Conclusion: Although, the concentrations of chromium in the analysed samples were not much higher than what were obtained in literature, they may be enough to sensitize the population that is allergic to chromium.

  7. Development Of The Computer Code For Comparative Neutron Activation Analysis

    International Nuclear Information System (INIS)

    The qualitative and quantitative chemical analysis with Neutron Activation Analysis (NAA) is an importance utilization of a nuclear research reactor, and this should be accelerated and promoted in application and its development to raise the utilization of the reactor. The application of Comparative NAA technique in GA Siwabessy Multi Purpose Reactor (RSG-GAS) needs special (not commercially available yet) soft wares for analyzing the spectrum of multiple elements in the analysis at once. The application carried out using a single spectrum software analyzer, and comparing each result manually. This method really degrades the quality of the analysis significantly. To solve the problem, a computer code was designed and developed for comparative NAA. Spectrum analysis in the code is carried out using a non-linear fitting method. Before the spectrum analyzed, it was passed to the numerical filter which improves the signal to noise ratio to do the deconvolution operation. The software was developed using the G language and named as PASAN-K The testing result of the developed software was benchmark with the IAEA spectrum and well operated with less than 10 % deviation

  8. Instrumental neutron activation analysis of prehistoric and ancient bone remains

    International Nuclear Information System (INIS)

    Instrumental neutron activation analysis (INAA) was used to study the element contents in bones of prehistoric dinosaurs and bones of an ancient bear and an archantrop (ancient person), which were found on the territory of Uzbekistan. Concentrations of more than 25 elements were in the range of 0.043-3600 mg/kg. Multielement analyses of bone and soil samples were carried out by INAA using the WWR-SM research nuclear reactor. Results of measurements have shown that in the dinosaurs bones the concentration of the rare earth elements (REEs) were within 280-3200 mg/kg; the uranium content reached a very high value, up to 180 mg/kg, while in soils coating the dinosaurs bones this content was 4.2 mg/kg; in the bones of the archantrop it was 1.53 mg/kg and in the bones of a standard person its amount is less than 0.016 mg/kg. (author)

  9. Neutron activation analysis in receptor modeling in environmental chemistry

    International Nuclear Information System (INIS)

    The release of air pollutants in high enough concentrations can have adverse health effects on the general public, particularly in urban areas. To develop strategies to manage the quality of air pollution, it is necessary to understand the flow of materials through the system, the sources and sinks, transformation, and transport pathways of the species of interest. An approach that is extensively being used in our laboratories, as well as in many others, is the use of receptor modeling. These models are based on the concepts of conservation of mass and a mass balance analysis, which in turn is based on the characterization of airborne particles into their constituents. From these methods, sources contributing to air quality are identified from the perspective of the receptor or ambient sampler. Separation of the ambient particles containing trace elements into distinct size classes allows the study of various sources to be identified. Another reason for the rapid development of receptor models has been the concurrent development of a variety of analytical techniques that permit greatly improved analyses to provide the needed input data. Two of the most powerful methods are instrumental neutron activation analysis (INAA) and X-ray fluorescence (XRF), including particle-induced X-ray emission. By using these methods along with sophisticated receptor modeling and size fractionation, the authors have been able to identify specific sources of local and regional air pollution

  10. Neutron activation analysis and provenance study of Tupiguarani Tradition pottery

    Energy Technology Data Exchange (ETDEWEB)

    Faria, Gleikam Lopes de Oliveira [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/ CNEN-MG), Belo Horizonte, MG (Brazil). Curso de Mestrado em Ciencia e Tecnologia das Radiacoes, Minerais e Materiais], e-mail: gleikam@yahoo.com.br; Menezes, Maria Angela de B.C. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/ CNEN-MG), Belo Horizonte, MG (Brazil). Servico de Reator e Tecnicas Analiticas. Lab. de Ativacao Neutronica], e-mail: menezes@cdtn.br; Ribeiro, Loredana; Jacome, Camila [Cooperativa dos Empreendedores em Acoes Culturais - COOP. CULTURA, Belo Horizonte, MG (Brazil). Lab. de Arqueologia], e-mail: loredana.ribeiro@gmail.com

    2009-07-01

    Archaeology can fill the gap between ancient population and modern society elucidating the evidences found in archaeological sites. The fingerprint identified, that is the chemical composition of the ceramics, can help understanding this connection between the past and the present. The Tupiguarani Tradition vestiges found by archaeologists will be a way to know about the last two millennia of the Brazilian prehistory. This archaeological site is located along the coast of the Brazilian State of Espirito Santo, where the main evidence is a pretty ceramic with the occurrence of plastic and painted decoration. When the Portuguese settlers arrived in this region, in sixteenth century, several Missoes Jesuiticas (Jesuitical Missions) were built along the Brazilian coast. In spite of living within the Mission and been catechized, the Indians kept on producing traditional handicraft, as the decorated ceramic, however, they introduced European elements to the decoration. During the research expeditions made to the archaeological site of the Tupiguarani Tradition, many sherds were found. The identification and classification of ceramics through a multielemental chemistry analysis will be used to determine if they have the same origin. This paper shows the first elemental concentration results of the sherds collected from archaeological site determined at CDTN/CNEN, Belo Horizonte, Minas Gerais, using the TRIGA Mark I IPR-R1 nuclear reactor, applying the neutron activation technique, k{sub 0}-method. (author)

  11. Inorganic constituents in herbal medicine by neutron activation analysis

    International Nuclear Information System (INIS)

    The demand for herbal medicines is growing worldwide. The expansion of interest has required the standardization of the sector with implementation and constant review of technical standards for production and marketing of these medicines in order to ensure the safe use, therapeutic efficacy and quality of the products. According to data from the World Health Organization, approximately 80% of world population has resorted to the benefits of certain herbs with therapeutic action popularly recognized. Despite the vast flora and the extensive use of medicinal plants by the population, it is a consensus that scientific studies on the subject are insufficiency. Therefore, it is necessary to stimulate such studies in view of the importance of the results of both individual and social field. The determination of major, minor and trace elements and the research of metabolic processes and their impacts on human health are of great importance due to the growth of environmental pollution that directly affects the plants and therefore the phytotherapics. Therefore, the objective of this work was to determine the content of inorganic constituents in herbal medicine: moisture, total ash and the elements As, Ba, Br, Ca, Cs, Co, Cr, Fe, Hf, K, Na, Rb, Sb, Sc, Se, Ta, Th, U, Zn and Zr by neutron activation analysis in order to verify the quality of the products. It was observed that the elemental concentrations varied in a wide range from plant to plant and elements with higher concentrations were Ba, Fe, Cr and Zn. (author)

  12. Elementary concentration of Peruibe black mud by neutron activation analysis

    International Nuclear Information System (INIS)

    The Peruibe Black Mud is used in therapies such as psoriasis, peripheral dermatitis, acne, seborrehea, myalgia arthritis and rheumatic non-articular processes. This material is characterized by is fine organic matter particles, sulphate reducing bacteria and a high content of potential reduction ions. Although this material is particles, sulphate reducing bacteria and a high content of potential reduction ions. Although this material is considered natural, it may not be free of possible adverse health effects, like toxic chemical elements, when used for therapeutic purposes. In the therapeutic treatments involving clays, clays are used in mud form also called peloids, obtained by maturation process. Five in natura and three maturated Black Mud samples were collected in Peruibe city, Sao Paulo State, Brazil. To investigate the distribution of major, trace and rare earth elements in the in natura and maturated clays that constitute the Peruibe Black Mud, neutron activation analysis (NAA) was used. A comparison between in natura and maturated mud shows that major, trace and rare earth elements follow the same order in both types. Generally, the concentrations in the maturated mud are slightly lower than in natura mud. Enrichment on the upper continental crust could be observed for the elements As, Br, Sb and Se, in these types of mud. (author)

  13. Essential trace elements in edible mushrooms by Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Mushrooms are excellent nutritional sources since they provide proteins, fibers and mineral, such as K, P, Fe. They have also been the focus of medical research. In Brazil mushrooms are not consumed in large quantities by the general population since people know little about the nutritional and medicinal benefits that mushrooms offer. Hence, this study intends to contribute to a better understanding of the essential element content in edible mushrooms, which are currently commercialized in Sao Paulo state. Br Fe, K, Na and Zn concentrations were determined by Instrumental Neutron Activation Analysis in the following mushroom species: Shitake (Lentinus edodes), Shimeji (Pleurotus ssp), Paris Champignon (Agaricus bisporus), Hiratake ( Pleurotus ssp) and Eringue (Pleurotus Eryngu. The mushroom samples were acquired from commercial establishments in the city of Sao Paulo and directly from the producers. Essential element contents in mushrooms varied between Br 0.03 to 4.1 mg/kg; Fe 20 to 267 mg/kg; K 1.2 to 5.3 g/kg, Na 10 to 582 mg/kg and Zn 60 to 120 mg/kg. The results confirm that mushrooms can be considered a good source of K, Fe and Zn. The low Na level is a good nutritional benefit for the consumer. (author)

  14. Neutron activation analysis of lipsticks using gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Neutron activation analysis with gamma-ray spectrometry was used to measure the concentrations of various elements in lipsticks of popular Indian and foreign brands. The aim of the present work was to study the possibility of existence of trace elements in samples of lipsticks (the ingredients of which are mostly organic in nature) and to see whether trace elements could distinguish lipsticks of different Indian and foreign brands from the forensic point of view apart from their inter-se differentiation. In the different samples of lipsticks that were analysed the following elements were detected: Au, Ba, Br, Ca, Cs, Fe, Na, Ru, Sb, Sc, Ta, Yb, Zn, Rb and Se. It was found that inter-se differentiation of lipsticks was possible on the basis of concentrations of trace elements and their profile. Concentration of bromine in samples of lipsticks identified lipsticks of different Indian brands. Samples of lipsticks of Indian and foreign brands could be differentiated on the basis of concentrations of cesium, antimony and scandium which were found to be higher in foreign brands as compared to those in Indian brands. (authors)

  15. Elementary concentration of Peruibe black mud by neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Torrecilha, Jefferson K.; Ponciano, Ricardo; Silva, Paulo S.C da, E-mail: jeffkoy@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The Peruibe Black Mud is used in therapies such as psoriasis, peripheral dermatitis, acne, seborrehea, myalgia arthritis and rheumatic non-articular processes. This material is characterized by is fine organic matter particles, sulphate reducing bacteria and a high content of potential reduction ions. Although this material is particles, sulphate reducing bacteria and a high content of potential reduction ions. Although this material is considered natural, it may not be free of possible adverse health effects, like toxic chemical elements, when used for therapeutic purposes. In the therapeutic treatments involving clays, clays are used in mud form also called peloids, obtained by maturation process. Five in natura and three maturated Black Mud samples were collected in Peruibe city, Sao Paulo State, Brazil. To investigate the distribution of major, trace and rare earth elements in the in natura and maturated clays that constitute the Peruibe Black Mud, neutron activation analysis (NAA) was used. A comparison between in natura and maturated mud shows that major, trace and rare earth elements follow the same order in both types. Generally, the concentrations in the maturated mud are slightly lower than in natura mud. Enrichment on the upper continental crust could be observed for the elements As, Br, Sb and Se, in these types of mud. (author)

  16. Neutron activation analysis: A primary method of measurement

    Science.gov (United States)

    Greenberg, Robert R.; Bode, Peter; De Nadai Fernandes, Elisabete A.

    2011-03-01

    Neutron activation analysis (NAA), based on the comparator method, has the potential to fulfill the requirements of a primary ratio method as defined in 1998 by the Comité Consultatif pour la Quantité de Matière — Métrologie en Chimie (CCQM, Consultative Committee on Amount of Substance — Metrology in Chemistry). This thesis is evidenced in this paper in three chapters by: demonstration that the method is fully physically and chemically understood; that a measurement equation can be written down in which the values of all parameters have dimensions in SI units and thus having the potential for metrological traceability to these units; that all contributions to uncertainty of measurement can be quantitatively evaluated, underpinning the metrological traceability; and that the performance of NAA in CCQM key-comparisons of trace elements in complex matrices between 2000 and 2007 is similar to the performance of Isotope Dilution Mass Spectrometry (IDMS), which had been formerly designated by the CCQM as a primary ratio method.

  17. Neutron activation analysis of human hair and health

    International Nuclear Information System (INIS)

    Full text: Periodically increasing and decreasing enthusiasm has accompanied the studies of medical significance of human hair elemental composition for at least two decades. In this field, nuclear analytical methods play an extremely important role, especially the instrumental neutron activation analysis (INAA). This paper tries to add some new knowledge to this problem. There were collected and analyzed hair samples from 2 500 practically healthy inhabitants of Uzbekistan. This allowed to estimate average concentrations of elements and intervals of concentration for normal population. Average data for 11 regions of Uzbekistan were compared with medical statistics data for these regions. There were found significant correlations for some diseases. In addition were found correlations in world wide scale. These data and previously obtained data in clinical conditions allowed to elaborate algorithm of estimation of health status according to human hair elemental composition. Reliability for many cases was very high. This allows to focus for more detailed diagnostic procedures and measures for the body elemental status correction

  18. Neutron activation analysis of toxic elements in meat and farinaceous food of Argentina

    International Nuclear Information System (INIS)

    Quantitative information about the concentration of toxic elements in foodstuffs for human consumption is important for the study of human health and diseases. Our project is to analyze, by neutron activation, toxic elements im meat and farinaceous food of Argentina by means of: a) Radiochemical neutron activation analysis with development of an adequate technique for the determination of As, Se, Sb and Hg in farinaceous food and manufactured meat (sausages and hamburgers); b) Instrumental neutron activation analysis of Rb, Se, Br, Fe, Co and Zn in farinaceous food and manufactured meat; c) Preliminary studies of the daily intake of the determined elements. 5 refs, 3 figs, 17 tabs

  19. Instrumental neutron-activation analysis of geological samples for rare earths using internal standard method

    International Nuclear Information System (INIS)

    Full text: Instrumental neutron-activation analysis os one of a few modern analytical techniques, being applied to solve difficult analytical tasks, such as mineral resources analysis for rare earth element content. No other analytical technique can be used with the latter end in view, since Instrumental neutron-activation analysis is possessed of the highest precision among them. In order to check experimentally the stated approach to REE content calculation by the internal standard method, relative bias values of this approach should be estimated. This approach will be verified further with a number of different rock samples simultaneously analyzed by an instrumental neutron-activation analysis certified analytical technique

  20. Development of activation foils method for the IFMIF neutron flux characterization

    International Nuclear Information System (INIS)

    The International Fusion Material Irradiation Facility (IFMIF) will provide an accelerator based intense neutron source with a white spectrum extending up to 55 MeV for high fluence irradiations of fusion reactor candidate materials. Numerous computational efforts have been undertaken so far to simulate the IFMIF neutron source and to predict the spectral neutron fluxes and nuclear responses in the specimens and other components located inside the test cell. During IFMIF operation experimental methods will be needed to measure and monitor the neutron flux and to validate the computational tools and data developed for the neutronics predictions. This work proposes to use the activation foil method for the neutron spectrum determination in the IFMIF facility. This method was elaborated and applied mainly for fission reactors using rather well established dosimetry reaction cross sections up to 14-20 MeV. For application in high energy neutron fields we selected suitable elements and dosimetry reactions having thresholds and effective cross sections covering the whole IFMIF energy range up to 55 MeV. The available evaluated nuclear data libraries and experimental data were carefully screened to select appropriate dosimetry cross sections with uncertainties as low as possible. For the determination of the neutron spectra from the induced γ-activities the unfolding code SAND-II was applied after having it modified for the use of the selected dosimetry cross sections above 20 MeV. This approach was tested by measuring the white neutron spectrum at the cyclotron of Nuclear Physics Institute (Rez), where neutrons up to 35 MeV energy were generated by a 37 MeV proton beam impinging on a heavy water target. The paper concludes with recommendations for the procedure for determining the neutron energy differential flux in the IFMIF test cell with respect to the size of the dosimetry foils, the irradiation time and the expected induced activities. (author)