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Sample records for in-situ gamma spectrometry

  1. Detector calibration for in-situ gamma ray spectrometry

    CERN Document Server

    Balea, G

    2002-01-01

    The power in the technique of in-situ spectrometry lies in the fact that a detector placed on ground measures gamma radiation from sources situated over an area of several hundred square meters. The 'field of view' for the detector would be larger for high energy radiation sources and for sources closer to the soil surface. In contrast, a soil sample would represent an area of a few tens of hundreds of square centimeters. In practice, an effective characterization of a site would involve in-situ gamma ray spectrometry in conjunction with soil sampling. As part of an overall program, in-situ gamma ray spectrometry provides a means to assess the degree of contamination in areas during the course of operations in the field, thus guiding the investigator on where to collect samples. It can also substantially reduce the number of samples need to be collected and subsequently analyzed. (author)

  2. Demonstration of a collimated in situ method for determining depth distributions using gamma-ray spectrometry

    CERN Document Server

    Benke, R R

    2002-01-01

    In situ gamma-ray spectrometry uses a portable detector to quantify radionuclides in materials. The main shortcoming of in situ gamma-ray spectrometry has been its inability to determine radionuclide depth distributions. Novel collimator designs were paired with a commercial in situ gamma-ray spectrometry system to overcome this limitation for large area sources. Positioned with their axes normal to the material surface, the cylindrically symmetric collimators limited the detection of un attenuated gamma-rays from a selected range of polar angles (measured off the detector axis). Although this approach does not alleviate the need for some knowledge of the gamma-ray attenuation characteristics of the materials being measured, the collimation method presented in this paper represents an absolute method that determines the depth distribution as a histogram, while other in situ methods require a priori knowledge of the depth distribution shape. Other advantages over previous in situ methods are that this method d...

  3. In-situ gamma spectrometry method for determination of environmental gamma dose

    International Nuclear Information System (INIS)

    Conti, Claudio de Carvalho

    1995-07-01

    This work tries to establish a methodology for germanium detectors calibration, normally used for in situ gamma ray spectrometry, for determining the environmental exposure rate in function of the energy of the incident photons. For this purpose a computer code has been developed, based on the stripping method, for the computational spectra analysis to calculate the contribution of the partial absorption of the gamma rays (Compton effect) in the active and nonactive parts of the detector. The resulting total absorption spectrum is then converted to fluence distribution in function of the energy for the photons reaching the detector, which is then used to calculate the exposure rate or kerma in air. The unfolding and fluency convention parameters are determined by detector calibration using point gamma sources. The method is validated by comparison of the results against the calculated exposure rate at a point of interest for the standards. This method is used for the direct measurement of the exposure rate distribution in function of the energy at the site, in situ measurement technic, leading to rapid results during an emergency situation and also used for indoor measurements. (author)

  4. Results from the first national in-situ gamma spectrometry survey of the United Kingdom

    International Nuclear Information System (INIS)

    Tyler, A.

    2004-01-01

    In-situ gamma spectrometry was introduced for the first time as part of a national soil and herbage pollution survey of the United Kingdom (UK) in 2002. The aim of introducing the in-situ approach was to evaluate its potential for replacing the conventional soil sampling approach in environmental monitoring. A total of 138 points were measured across the whole of the UK on a 50 km grid, encompassing a complete spectrum of soil types, geology (providing a range of natural radioactive backgrounds) and anthropogenic radioactivity (primarily derived from atmospheric weapons testing and Chernobyl fallout). Ten calibration sites were set up to derive an in-situ calibration from spatially distributed sampling points, designed to match the spatial response of the in-situ detector at 1 m above the ground. The importance of variations in the vertical activity distributions of 137 Cs on the in-situ detector calibration was verified and the advantages and disadvantages of implementing a forward scattering type approach for real time in-situ correction was evaluated. The accuracy of the in-situ calibrations was evaluated for the remaining 128 sites by independent comparison with soil core derived estimates of specific activity concentrations and inventories of a range of natural and anthropogenic gamma emitting radionuclides. Air kerma measurements were also derived from the in-situ gamma spectrometry measurements and compared with conventional GM tube derived estimates. (authors)

  5. In-situ gamma spectrometry method for determination of environmental gamma dose; Metodo de espectrometria gamma in situ para determinacao de dose gama ambiental

    Energy Technology Data Exchange (ETDEWEB)

    Conti, Claudio de Carvalho

    1995-07-15

    This work tries to establish a methodology for germanium detectors calibration, normally used for in situ gamma ray spectrometry, for determining the environmental exposure rate in function of the energy of the incident photons. For this purpose a computer code has been developed, based on the stripping method, for the computational spectra analysis to calculate the contribution of the partial absorption of the gamma rays (Compton effect) in the active and nonactive parts of the detector. The resulting total absorption spectrum is then converted to fluence distribution in function of the energy for the photons reaching the detector, which is then used to calculate the exposure rate or kerma in air. The unfolding and fluency convention parameters are determined by detector calibration using point gamma sources. The method is validated by comparison of the results against the calculated exposure rate at a point of interest for the standards. This method is used for the direct measurement of the exposure rate distribution in function of the energy at the site, in situ measurement technic, leading to rapid results during an emergency situation and also used for indoor measurements. (author)

  6. New portability for in situ gamma-ray spectrometry from commercially available equipment

    International Nuclear Information System (INIS)

    Stanford, N.; Laurenzo, E.L.; McCurdy, D.E.

    1984-01-01

    In situ gamma-ray spectrometry has been employed by the staff of the Yankee Atomic Environmental Laboratory on a routine basis for more than five years. The original in situ gamma-ray spectrometry methodology was adopted from the techniques developed at the DOE Environmental Measurements Laboratory (Beck, DeCampo, and Gogolak 1972). The system consisted of a 110 cm 3 Ge(Li) detector in the vertical configuration in conjunction with typical laboratory nuclear instrumentation, as well as a medium-sized desktop computer, printer and disk drive. The equipment was transported in a small van having a shock-mounted cabinet and gasoline generator as an electrical power source. Recent availability of miniaturized spectrometry systems and powerful portable computers has enabled the upgrading of the 1977 vintage equipment to a system which is truly portable, light weight, compact and more reliable. The system to be described utilizes a portable intrinsic germanium detector, a small, 4096 channel pulse height analyzer (MCA) with anscillary components and a 24K, Hewlett Packard HP-75 computer with a small tape drive. When the equipment is used in the field, the system has enough capability to acquire and store a full 4096 channel gamma-ray spectrum and calculate the soil concentrations (pCi/g) and/or external radiation exposure rates for the commonly found naturally occurring, long-lived atmospheric nuclear weapons testing and nuclear power plant radionuclides. Subsequent data transfer to a larger desktop computer via available interfacing at the laboratory enables a full peak search and a more extensive evaluation of the data in order to calculate the soil concentrations and/or external radiation exposure rates for a selected 25 radionuclides. Experiences from the first season of operation are discussed

  7. Determination of Th and U by neutron activation for gamma spectrometry calibration in situ

    International Nuclear Information System (INIS)

    Nava M, F.; Rios M, C.; Mireles G, F.; Saucedo A, S.; Davila R, I.; Pinedo, J. L.; Landsberger, S.

    2012-10-01

    Using the analysis by neutron activation to determine the profile of the thorium and uranium concentration calibration factors were obtained for their use in the gamma spectrometry in situ. Three sites were selected (San Ramon, Villa de Cos y la Zacatecana) and the analysis by activation was development in the Laboratory of Nuclear Engineering Teaching of the Texas University in Austin with the nuclear reactor Ut-TRIGA. Starting from the gamma spectra in situ, the areas of normalized photo-pick of the radioisotopes were: 208 Tl and 228 Ac for the thorium series and 214 Pb and 214 Bi for the uranium series. The averages of the factors found in units of (cpm/Bq/Kg) are of 105.63±8.32 and 75.87±4.61 for the thorium and uranium, respectively. (Author)

  8. An intercomparison of Monte Carlo codes used for in-situ gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Hurtado, S.; Villa, M.

    2010-01-01

    In-situ gamma-ray spectrometry is widely used for monitoring of natural as well as man-made radionuclides and corresponding gamma fields in the environment or working places. It finds effective application in the operational and accidental monitoring of nuclear facilities and their vicinity, waste depositories, radioactive contamination measurements and environmental mapping or geological prospecting. In order to determine accurate radionuclide concentrations in these research fields, Monte Carlo codes have recently been used to obtain the efficiency calibration of in-situ gamma-ray detectors. This work presents an inter-comparison between two Monte Carlo codes applied to in-situ gamma-ray spectrometry. On the commercial market, Canberra has its LABSOCS/ISOCS software which is relatively inexpensive. The ISOCS mathematical efficiency calibration software uses a combination of Monte Carlo calculations and discrete ordinate attenuation computations. Efficiencies can be generated in a few minutes in the field and can be modified easily if needed. However, it has been reported in the literature that ISOCS computation method is accurate on average only within 5%, and additionally in order to use LABSOCS/ISOCS it is necessary a previous characterization of the detector by Canberra, which is an expensive process. On the other hand, the multipurpose and open source GEANT4 takes significant computer time and presents a non-friendly but powerful toolkit, independent of the manufacturer of the detector. Different experimental measurements of calibrated sources were performed with a Canberra portable HPGe detector and compared to the results obtained using both Monte Carlo codes. Furthermore, a variety of efficiency calibrations for different radioactive source distributions were calculated and tested, like plane shapes or containers filled with different materials such as soil, water, etc. LabSOCS simulated efficiencies for medium and high energies were given within an

  9. Gamma-ray spectrometry laboratory and in situ: developments and environmental applications

    International Nuclear Information System (INIS)

    Gasser, Estelle

    2014-01-01

    Gamma-ray spectrometry enables determining all γ-ray emitters in a sample with a single measurement. Self-absorption of γ-rays in samples is manifest by a loss or a gain of pulses that results in a poor estimation of the counting efficiency. To characterize a new counting geometry improvements of the existing set-up were made with MCNPX simulations. With the new geometry we could specify absorbed and annual effective doses as well as dose conversion factors for the natural radioisotopes of several building materials and soil samples. Simulations show the influence of detection limits of γ-radiation on dose conversion factors and the need for updating these factors. γ-ray measurements of soil in situ require different counting efficiencies simulated by MCNPX for a semi-infinite source. Two in-situ soil analyses were made, one around a nuclear power and the other for a private company. (author)

  10. Comparison of in-situ gamma ray spectrometry measurements with conventional methods in determination natural and artificial nuclides in soil

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Doubal, A. W.

    2010-12-01

    Two nuclear analytical techniques (In-Situ Gamma ray spectrometry and laboratory gamma ray spectrometry) for determination of natural and artificial radionuclides in soil have been validated. The first technique depends on determination of radioactivity content of representative samples of the studied soil after laboratory preparation, while the second technique is based on direct determination of radioactivity content of soil using in-situ gamma-ray spectrometer. Analytical validation parameter such as detection limits, repeatability, reproducibility in addition to measurement uncertainties were estimated and compared for both techniques. Comparison results have shown that the determination of radioactivity in soil should apply the two techniques together where each of techniques is characterized by its low detection limit and uncertainty suitable for defined application of measurement. Radioactive isotopes in various locations were determined using the two methods by measuring 40 k, 238 U,and 137 Cs. The results showed that there are differences in attenuation factors due to soil moisture content differences; wet weight corrections should be applied when the two techniques are compared. (author)

  11. Determination of Th and U by neutron activation for gamma spectrometry calibration in situ; Determinacion de Th y U por activacion neutronica para calibracion de espectrometria gamma in situ

    Energy Technology Data Exchange (ETDEWEB)

    Nava M, F.; Rios M, C.; Mireles G, F.; Saucedo A, S.; Davila R, I.; Pinedo, J. L. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas (Mexico); Landsberger, S., E-mail: iqnava@hotmail.com [University of Texas at Austin, Nuclear Engineering Teaching Laboratory, Pickle Research Campus, R9000 Austin, Texas 78712 (United States)

    2012-10-15

    Using the analysis by neutron activation to determine the profile of the thorium and uranium concentration calibration factors were obtained for their use in the gamma spectrometry in situ. Three sites were selected (San Ramon, Villa de Cos y la Zacatecana) and the analysis by activation was development in the Laboratory of Nuclear Engineering Teaching of the Texas University in Austin with the nuclear reactor Ut-TRIGA. Starting from the gamma spectra in situ, the areas of normalized photo-pick of the radioisotopes were: {sup 208}Tl and {sup 228}Ac for the thorium series and {sup 214}Pb and {sup 214}Bi for the uranium series. The averages of the factors found in units of (cpm/Bq/Kg) are of 105.63{+-}8.32 and 75.87{+-}4.61 for the thorium and uranium, respectively. (Author)

  12. An improved in situ method for determining depth distributions of gamma-ray emitting radionuclides

    International Nuclear Information System (INIS)

    Benke, R.R.; Kearfott, K.J.

    2001-01-01

    In situ gamma-ray spectrometry determines the quantities of radionuclides in some medium with a portable detector. The main limitation of in situ gamma-ray spectrometry lies in determining the depth distribution of radionuclides. This limitation is addressed by developing an improved in situ method for determining the depth distributions of gamma-ray emitting radionuclides in large area sources. This paper implements a unique collimator design with conventional radiation detection equipment. Cylindrically symmetric collimators were fabricated to allow only those gamma-rays emitted from a selected range of polar angles (measured off the detector axis) to be detected. Positioned with its axis normal to surface of the media, each collimator enables the detection of gamma-rays emitted from a different range of polar angles and preferential depths. Previous in situ methods require a priori knowledge of the depth distribution shape. However, the absolute method presented in this paper determines the depth distribution as a histogram and does not rely on such assumptions. Other advantages over previous in situ methods are that this method only requires a single gamma-ray emission, provides more detailed depth information, and offers a superior ability for characterizing complex depth distributions. Collimated spectrometer measurements of buried area sources demonstrated the ability of the method to yield accurate depth information. Based on the results of actual measurements, this method increases the potential of in situ gamma-ray spectrometry as an independent characterization tool in situations with unknown radionuclide depth distributions

  13. Source term estimation based on in-situ gamma spectrometry using a high purity germanium detector

    International Nuclear Information System (INIS)

    Pauly, J.; Rojas-Palma, C.; Sohier, A.

    1997-06-01

    An alternative method to reconstruct the source term of a nuclear accident is proposed. The technique discussed here involves the use of in-situ gamma spectrometry. The validation of the applied methodology has been possible through the monitoring of routine releases of Ar-41 originating at a Belgian site from an air cooled graphite research reactor. This technique provides a quick nuclide specific decomposition of the source term and therefore will be have an enormous potential if implemented in nuclear emergency preparedness and radiological assessments of nuclear accidents during the early phase

  14. In situ gamma spectrometry development for site mapping

    International Nuclear Information System (INIS)

    Panza, F.

    2012-01-01

    The high-resolution gamma spectrometry currently provides a powerful analytical tool for performing environmental measurements. In the context of radiological characterization of a site (natural or artificial radioactivity) and for the dismantling of nuclear installations, mapping of radionuclides is an important asset. The idea is to move a HPGe spectrometer to study the site and from nuclear and position data, to identify, to locate and to quantify the radionuclides present in the soil. The development of this tool follows an intercomparison (ISIS 2007) where an intervention/crisis exercise showed the limits of current tools. The main part of this research project has focused on mapping of nuclear data. Knowledge of the parameters of an in situ spectrum helped to create a simulator, modeling the response of a spectrometer moving over contaminated soil. The simulator itself helped to develop algorithms for mapping and to test them in extreme situations and not realizable. A large part of this research leads to the creation of a viable prototype providing real-time information concerning the identity and locality as possible radionuclides. The work performed on the deconvolution of data can make in post processing a map of the activity of radionuclide soil but also an indication of the depth distribution of the source. The prototype named OSCAR was tested on contaminated sites (Switzerland and Japan) and the results are in agreement with reference measurements. (author)

  15. Advances in continuous gamma-ray spectrometry and applications

    International Nuclear Information System (INIS)

    Gold, R.; McNeece, J.P.; Kaiser, B.J.

    1984-07-01

    Recent advances and applications in continuous Compton recoil gamma-ray spectrometry are described. Applications of continuous gamma-ray spectrometry are presented for: (1) Characterization of light water reactor (LWR) pressures vessel (PV) environments. (2) Assessment of fuel distributions for Three Mile Island Unit 2 (TMI-2) reactor recovery. (3) Measurement of LWR-PV-neutron exposure. The latest improvements attained with the Janus probe, a special in-situ configuration of Si(Li) detectors, are presented. The status of current efforts to extend the domain of applicability of this method beyond 3 MeV is discussed with emphasis on recent work carried out with Si(Li) detectors of much larger volume

  16. Survey of the 137Cs contamination in Belgium by in-situ gamma spectrometry, a decade after the Chernobyl accident.

    Science.gov (United States)

    Uyttenhove, J; Pommé, S; Van Waeyenberge, B; Hardeman, F; Buysse, J; Culot, J P

    1997-10-01

    The residual radiocesium concentration, nearly 10 y after the Chernobyl accident, is measured at different sites on the Belgian territory by means of in-situ gamma-spectrometry. A possible link between the rainfall at the beginning of May 1986 and the actual cesium concentration is investigated. The radiological impact of this contamination, even in the most affected regions in the Ardennes, is very small (<6 microSv y(-1)).

  17. Spatially-Dependent Measurements of Surface and Near-Surface Radioactive Material Using In situ Gamma Ray Spectrometry (ISGRS) For Final Status Surveys

    International Nuclear Information System (INIS)

    J. A. Chapman, A. J. Boerner, E. W. Abelquist

    2006-01-01

    In-situ, high-resolution gamma-ray spectrometry (ISGRS) measurements were conducted at the Oak Ridge Institute for Science and Education ORISE field laboratory in Oak Ridge, Tennessee. The purpose of these tests was to provide analytical data for assessing how 'fit for use' this technology is for detecting discrete particles in soil

  18. Spatially-Dependent Measurements of Surface and Near-Surface Radioactive Material Using In situ Gamma Ray Spectrometry (ISGRS) For Final Status Surveys

    Energy Technology Data Exchange (ETDEWEB)

    J. A. Chapman, A. J. Boerner, E. W. Abelquist

    2006-11-15

    In-situ, high-resolution gamma-ray spectrometry (ISGRS) measurements were conducted at the Oak Ridge Institute for Science and Education (ORISE) field laboratory in Oak Ridge, Tennessee. The purpose of these tests was to provide analytical data for assessing how “fit for use” this technology is for detecting discrete particles in soil.

  19. Janus probe, a detection system for high energy reactor gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Gold, R.; Kaiser, B.J.

    1980-03-01

    In reactor environments, gamma-ray spectra are continuous and the absolute magnitude as well as the general shape of the gamma continuum are of paramount importance. Consequently, conventional methods of gamma-ray detection are not suitable for in-core gamma-ray spectrometry. To meet these specific needs, a method of continuous gamma-ray spectrometry, namely Compton Recoil Gamma-Ray Spectrometry, was developed for in-situ observations of reactor environments. A new gamma-ray detection system has been developed which extends the applicability of Compton Recoil Gamma-Ray Spectrometry up to roughly 7 MeV. This detection system is comprised of two separate Si(Li) detectors placed face-to-face. Hence this new detection system is called the Janus probe. Also shown is the block diagram of pulse processing instrumentation for the Janus probe. This new gamma probe not only extends the upper energy limit of in-core gamma-ray spectrometry, but in addition possesses other fundamental advantages

  20. Applicability study of using in-situ gamma-ray spectrometry technique for 137Cs and 210Pbex inventories measurement in grassland environments

    International Nuclear Information System (INIS)

    Li Junjie; Li Yong; Wang Yanglin; Wu Jiansheng

    2010-01-01

    In-situ measurement of fallout radionuclides 137 Cs and 210 Pb ex has the potential to assess soil erosion and sedimentation rapidly. In this study, inventories of 137 Cs and 210 Pb ex in the soil of Inner Mongolia grassland were measured using an In-situ Object Counting System (ISOCS). The results from the field study indicate that in-situ gamma-ray spectrometry has the following advantages over traditional laboratory measurements: no extra time is required for sample collection, no reference inventories are required, more economic, prompt availability of the results, the ability to average radionuclide inventory over a large area, and high precision.

  1. Theory of in situ gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Balea, G.

    2002-01-01

    The technique of in situ spectrometry had its origin during the time of atmospheric nuclear weapons testing when is was found to provide quick, reliable information on the components of the outdoor environment. It provided a means to separate natural background from man-made sources and gave quantitative results. Over the years, it has been employed by various groups for assessing radiation sources in the environment not only via ground based detectors, but with aircraft systems as well. It proved particularly useful after the Chernobyl accident and was employed by a number of European laboratories. It should prove adaptable to site assessment in the current era of environmental rescue. (author)

  2. Reactor gamma spectrometry: status

    International Nuclear Information System (INIS)

    Gold, R.; Kaiser, B.J.

    1979-01-01

    Current work is described for Compton Recoil Gamma-Ray Spectrometry including developments in experimental technique as well as recent reactor spectrometry measurements. The current status of the method is described concerning gamma spectromoetry probe design and response characteristics. Emphasis is given to gamma spectrometry work in US LWR and BR programs. Gamma spectrometry in BR environments are outlined by focussing on start-up plans for the Fast Test Reactor (FTR). Gamma spectrometry results are presented for a LWR pressure vessel mockup in the Poolside Critical Assembly (PCA) at Oak Ridge National Laboratory

  3. In-situ spectrometry of 137Cs in the soil by unfolding method

    International Nuclear Information System (INIS)

    Fueloep, M.; Ragan, P.; Krnac, S.

    1995-01-01

    This contribution is aimed to the possibility of improving the in-situ gamma spectrometry to be independent on a knowledge about a depth distribution of 137 Cs in soil and sufficiently sensitive for the measurement of the post-Chernobyl 137 Cs at present, as well. The depth distribution of 137 Cs averaged over a large area of soil is obtained by unfolding of the detector responses to primary and in soil forward scattered photons. The proposed method employs detector with and without collimator. The 137 Cs distributions obtained in-situ measurements are analysed, and comparisons are made to the results obtained with soil sampling and with standard in-situ spectrometry, as well. 5 figs., 1 tab., 4 refs

  4. Medium-term experiences with in-situ gamma-spectrometry of the primary loop transport processes at Paks NPP

    International Nuclear Information System (INIS)

    Raics, P.; Sztaricskai, T.; Szabo, J.; Szegedi, S.

    2001-01-01

    Surface activity of 15 corrosion/erosion and fission products was determined by in-situ gamma-spectrometry for 2-2 locations on the hot and cold legs of each loop, respectively. Gamma-dosimetry in the assay points was performed. Activity profiles of ion exchange columns were analyzed. Combined measurements along the steam generators completed the characterization of the primary circuits. Most of this technique was regularly included into all maintenance periods. Data evaluation was performed for the surface contaminations as well as coolant activities and reactor operation features for years 1985-2001. Trends and tendencies were investigated in the time behavior of the specific activities. Asymmetry in the surface contamination at the primary loop points, cold-leg activity inversion, water chemistry effects, isotope selectivity were observed. Correlations in different parameters have been calculated and analyzed. (R.P.)

  5. In-situ-gamma-spectrometry intercomparison exercise in Salzburg, Austria, September 26-30, 1994

    International Nuclear Information System (INIS)

    Steger, F.; Lettner, H.; Andrasi, A.

    1996-06-01

    In-situ gamma spectrometry has become a useful method to assess the nuclide concentration of artificial and natural gamma-emitters in the soil. With such measurements it is possible to calculate the activity concentration in soil and also the nuclide specific exposure rates 1 m above ground. For the quality assurance of the measurements periodically intercomparison exercises are essential. To meet this requirement exercises were organised in different European countries since 1989. The last exercise in September 1994 was organised in Salzburg / Austria. The participation of 24 measurement teams from all over Europe emphasises the importance of the intercomparison. Salzburg was selected because the Province of Salzburg / Austria was among the heaviest contaminated region outside the former USSR by the Chernobyl fallout. Two different typical sites were selected for the measurements: Site 1 was inside the urban area of Salzburg on intensively used agricultural land which had not been disturbed since the fallout. This site is representative for intensively used agricultural regions in the Province of Salzburg. Site 2 was in the mountainous region of the Tauern on elevated altitude of approx. 1700 m. This site represents the soil and contamination conditions of the Alpine region. Both sites differ significantly in terms of different soil distribution and contents of natural and artificial radionuclides. Results of the intercomparison exercise are presented. (author)

  6. Evaluation of gamma ray fields by HPGE spectrometry in situ

    Energy Technology Data Exchange (ETDEWEB)

    Krnac, S; Slugen, V [Slovak Technical Univ., Bratislava (Slovakia); Ragan, P; Fueloep, M [Inst. of Preventive and Clinical Medicine, Bratislava (Slovakia)

    1996-12-31

    In this paper the in situ spectrometric measurement for application in gamma radiation dosimetry with portability and flexibility in use was studied. In order to allow operation of the detector in any orientation without liquid nitrogen (LN{sub 2}) spillage, a multi-attitude cryostat (MAC) has been used which consists of a Dewar with LN{sub 2} capacity of 7.0 litres and a holding time of 5 days. This allows the Dewar to be operated in the horizontal position, pointing vertically upward or vertically downward, without loss of LN{sub 2}. The MAC detector has been positioned in a 4{sup p}i{sup -}goniometer and, therefore is movable to any measurable angle. Pulses from the detector have been fed into a portable multichannel analyzer (Canberra 35+) with connection to a PC/AT compatible computer system. The main results and findings of present contribution may be summarized as follows: 1. A technique called the scaling confirmatory factor analysis (SCFA) presented else can be advantageously employed for determination of the response operator characterizing an influence of measuring device on physical gamma-spectra obtained. The in situ response operator has been reproduced only from the internal factors of appropriate latent structure that do not depend upon materials surrounding the detector. 2. The photon fluence rate response operator for in situ application has been obtained from the reduced response operator by a correction according to the geometric factor 4{sup p}i{sup (}r{sub 0}+r){sup 2}.The effective distance r{sub 0} has been determined via a performance of the radial calibration which yields a condition of, minimally, 10 cm distance of the detector cover from the potential sources. 3. The real incident gamma ray spectra achieved by application of the SCFA response allow direct evaluation of spectral distributions of the fundamental photon dosimetric quantities. (Abstract Truncated)

  7. Standard guide for high-resolution gamma-ray spectrometry of soil samples

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2004-01-01

    1.1 This guide covers the identification and quantitative determination of gamma-ray emitting radionuclides in soil samples by means of gamma-ray spectrometry. It is applicable to nuclides emitting gamma rays with an approximate energy range of 20 to 2000 keV. For typical gamma-ray spectrometry systems and sample types, activity levels of about 5 Bq (135 pCi) are measured easily for most nuclides, and activity levels as low as 0.1 Bq (2.7 pCi) can be measured for many nuclides. It is not applicable to radionuclides that emit no gamma rays such as the pure beta-emitting radionuclides hydrogen-3, carbon-14, strontium-90, and becquerel quantities of most transuranics. This guide does not address the in situ measurement techniques, where soil is analyzed in place without sampling. Guidance for in situ techniques can be found in Ref (1) and (2). This guide also does not discuss methods for determining lower limits of detection. Such discussions can be found in Refs (3), (4), (5), and (6). 1.2 This guide can be us...

  8. Multivariate statistical approximation of the in situ gamma-ray spectrometry of the State of Zacatecas, Mexico

    International Nuclear Information System (INIS)

    Lopez I, J. F.; Rios M, C.; Mireles G, F.; Saucedo A, S.; Davila R, I.; Pinedo, J.L.

    2017-09-01

    The environmental radioactivity evaluation is a key point in the assessment of the environmental quality. Through this, it can be found possible radioactive contamination, locate possible Uranium and Thorium deposits and evaluate the primordial isotopes concentration due to human activities. A radioactive map of the Zacatecas State, Mexico is under construction based on in situ gamma-ray spectrometry. The present work reports the results of the multivariate statistical approximation of the measured activity data. Based on Pearson correlation, the 228 Ac and 208 Tl activities are statistically significant, while the 214 Bi and 214 Pb activities are not statistically significant. These can be due to the existence or not of secular equilibrium in the Thorium and Uranium series. (Author)

  9. In-situ spectrometry of {sup 137}Cs in the soil by unfolding method

    Energy Technology Data Exchange (ETDEWEB)

    Fueloep, M; Ragan, P [Inst. of Preventive and Clinical Medicine, 833301 Bratislava (Slovakia); Krnac, S [Slovak Technical Univ., Bratislava (Slovakia)

    1996-12-31

    This contribution is aimed to the possibility of improving the in-situ gamma spectrometry to be independent on a knowledge about a depth distribution of {sup 137}Cs in soil and sufficiently sensitive for the measurement of the post-Chernobyl {sup 137}Cs at present, as well. The depth distribution of {sup 137}Cs averaged over a large area of soil is obtained by unfolding of the detector responses to primary and in soil forward scattered photons. The proposed method employs detector with and without collimator. The {sup 137}Cs distributions obtained in-situ measurements are analysed, and comparisons are made to the results obtained with soil sampling and with standard in-situ spectrometry, as well. 5 figs., 1 tab., 4 refs.

  10. Multivariate statistical approximation of the in situ gamma-ray spectrometry of the State of Zacatecas, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Lopez I, J. F.; Rios M, C.; Mireles G, F.; Saucedo A, S.; Davila R, I.; Pinedo, J.L., E-mail: fernandolf498@gmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas, Zac. (Mexico)

    2017-09-15

    The environmental radioactivity evaluation is a key point in the assessment of the environmental quality. Through this, it can be found possible radioactive contamination, locate possible Uranium and Thorium deposits and evaluate the primordial isotopes concentration due to human activities. A radioactive map of the Zacatecas State, Mexico is under construction based on in situ gamma-ray spectrometry. The present work reports the results of the multivariate statistical approximation of the measured activity data. Based on Pearson correlation, the {sup 228}Ac and {sup 208}Tl activities are statistically significant, while the {sup 214}Bi and {sup 214}Pb activities are not statistically significant. These can be due to the existence or not of secular equilibrium in the Thorium and Uranium series. (Author)

  11. Radiological Mapping of the Alkaline Intrusive Complex of Jombo, South Coastal Kenya by In-Situ Gamma-Ray Spectrometry

    Science.gov (United States)

    Kaniu, Ian; Darby, Iain G.; Kalambuka Angeyo, Hudson

    2016-04-01

    Carbonatites and alkaline intrusive complexes are rich in a variety of mineral deposits such as rare earth elements (REEs), including Nb, Zr and Mn. These are often associated with U and Th bearing minerals, including monazite, samarskite and pyrochlore. Mining waste resulting from mineral processing activities can be highly radioactive and therefore poses a risk to human health and environment. The Jombo complex located in Kenya's south coastal region is potentially one of the richest sources of Nb and REEs in the world. It consists of the main intrusion at Jombo hill, three associated satellite intrusions at Mrima, Kiruku and Nguluku hills, and several dykes. The complex is highly heterogeneous with regard to its geological formation as it is characterized by alkaline igneous rocks and carbonatites which also influence its radio-ecological dynamics. In-situ gamma spectrometry offers a low-cost, rapid and spatially representative radioactivity estimate across a range of landscapes compared to conventional radiometric techniques. In this work, a wide ranging radiological survey was conducted in the Jombo complex as follow up on previous studies[1,2], to determine radiation exposure levels and source distributions, and perform radiological risk assessments. The in-situ measurements were carried out using a 2.0 l NaI(Tl) PGIS-2 portable detector from Pico Envirotec Inc integrated with GPS, deployed for ground (back-pack) and vehicular gamma-ray spectrometry. Preliminary results of radiological distribution and mapping will be presented. [1] Patel, J. P. (1991). Discovery and Innovation, 3(3): 31-35. [2] Kebwaro, J. M. et. al. (2011). J. Phys. Sci., 6(13): 3105-3110.

  12. In situ gamma spectrometry aspects of an European intercomparison of national networks used to provide early warning of a nuclear accident

    International Nuclear Information System (INIS)

    Gurriaran, R.; Lemercier, M.; Bouisset, P.; Cagnat, X.; Saez-Vergara, J. C.; Tyler, A. N.

    2006-01-01

    In 2002, the EURADOS Working Group on Environmental Monitoring organised the second European intercomparison exercise of national network systems used to provide early warning in case of a nuclear accident. The aim of the exercise is to ensure consistent and comparable results reported by different countries during a nuclear accident, hence avoiding that the dose rate measurements reported present steps at national borders due to different calibrations or different measurement quantities being used. The exercise studied the response of the detectors to different situations: Free field site, a flat area covered with grass. The detectors where in presence of environmental radiation and point sources. Radioactive plume simulator. An incident was simulated by gradually increasing the ambient dose rate by values up to 50% of the normal value. Cosmic radiation site. A platform installed in the middle of a lake permitted to study the response of detectors to cosmic rays in the absence of other components. Ultra low background laboratory (UDO). Situated at 925 m in a salt mine this unique facility has a very low ambient dose (<1 nSv/h) and permitted the study of the response of detectors to collimated beams, in the absence of other components. The exercise was focused on the systems that continuously monitor the ambient dose rate but a novelty in the 2002 intercomparison was the participation of in situ gamma spectrometry teams. This presentation will focus on the in situ gamma spectrometry aspects: The interest of having the energy spectra information in order to discriminate the different contributors to the ambient dose, and the work that has been done in order to ensure an agreement between the dosimetry aspects and the spectrometry results

  13. In situ gamma-ray spectrometry: A tutorial for environmental radiation scientists

    International Nuclear Information System (INIS)

    Miller, K.M.; Shebell, P.

    1993-10-01

    This tutorial is intended for those in the environmental field who perform assessments in areas where there is radioactive contamination in the surface soil. Techniques will be introduced for performing on-site quantitative measurements of gamma radiation in the environment using high resolution germanium detectors. A basic understanding of ionizing radiation principles is assumed; however, a detailed knowledge of gamma spectrometry systems is not required. Emphasized is the practical end of operations in the field and the conversion of measured full absorption peak count rates in a collected spectrum to meaningful radiological quantities, such as the concentration of a radionuclide in the soil, activity per unit area, and dose rate in the air. The theory of operation and calibration procedures will be covered in detail to provide the necessary knowledge to adapt the technique to site-specific problems. Example calculations for detector calibration are also provided

  14. Determination of plutonium isotopic ratios and total concentration by gamma ray spectrometry

    International Nuclear Information System (INIS)

    Despres, Michele.

    1980-11-01

    A non-destructive method of analysis is being investigated for the control in situ of plutonium isotopic composition and total concentration in different matrix without preliminary calibration. The plutonium isotopic composition is determined by gamma-ray spectrometry using germanium detector systems. The same apparatus is used for direct measuring of the total plutonium concentration in solutions or solids by a differential attenuation technique based on two transmitted gamma rays with energies on both sides of the k shell absorption edge of plutonium [fr

  15. GammaSem Proceedings. A Nordic seminar for users of gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Straalberg, E. (ed.) (Institute for Energy Technolgy (Norway)); Berg, K. (National Institute of Radiation Protection (Denmark)); Dowdall, M. (Norwegian Radiation Protection Authority (Norway)) (and others)

    2010-11-15

    The project GammaSem was proposed to the NKS in 2008. The aim of the project was to arrange two seminars for users of gamma spectrometry, in 2009 and 2010. The seminars were meant to provide a forum for discussions and sharing of information on practical issues concerning gamma spectrometry and initiate a network of gamma spectrometry users in the Nordic countries. Such a Nordic network should strengthen the collaboration between laboratories and improve all participants' competence in practical gamma spectrometry. Both seminars' focus was practical challenges met by the users themselves, rather than theoretical matters. Scientists and users of gamma spectrometry from all five Nordic countries were invited to the seminar, as well as scientist from the Baltic countries. A total of 65 people signed up for GammaSem 2010; representing 30 different universities, commercial companies, research institutes and authorities. The working group concept as presented at last year's GammaSem, has not worked out as intended. The reason for this is probably because most of the laboratories that signed up to join the working groups, signed up because they wanted to learn more about the different subjects. In combination with the fact that no funding was made available for the working groups, it was difficult to establish goals on what to achieve. None of the working groups applied for funding from the NKS (or elsewhere) to establish separate projects. There is a big need for more cooperation and for training within the field of gamma spectrometry. This fact has been proved through these two seminars, both by the many different topics that have been discussed, but also by the huge interest for participating in the suggested series of workshop. The GammaSem seminars have thus provided a much welcomed starting point for a broader Nordic collaboration. (Author)

  16. GammaSem Proceedings. A Nordic seminar for users of gamma spectrometry

    International Nuclear Information System (INIS)

    Straelberg, E.; Berg, K.; Dowdall, M.

    2010-11-01

    The project GammaSem was proposed to the NKS in 2008. The aim of the project was to arrange two seminars for users of gamma spectrometry, in 2009 and 2010. The seminars were meant to provide a forum for discussions and sharing of information on practical issues concerning gamma spectrometry and initiate a network of gamma spectrometry users in the Nordic countries. Such a Nordic network should strengthen the collaboration between laboratories and improve all participants' competence in practical gamma spectrometry. Both seminars' focus was practical challenges met by the users themselves, rather than theoretical matters. Scientists and users of gamma spectrometry from all five Nordic countries were invited to the seminar, as well as scientist from the Baltic countries. A total of 65 people signed up for GammaSem 2010; representing 30 different universities, commercial companies, research institutes and authorities. The working group concept as presented at last year's GammaSem, has not worked out as intended. The reason for this is probably because most of the laboratories that signed up to join the working groups, signed up because they wanted to learn more about the different subjects. In combination with the fact that no funding was made available for the working groups, it was difficult to establish goals on what to achieve. None of the working groups applied for funding from the NKS (or elsewhere) to establish separate projects. There is a big need for more cooperation and for training within the field of gamma spectrometry. This fact has been proved through these two seminars, both by the many different topics that have been discussed, but also by the huge interest for participating in the suggested series of workshop. The GammaSem seminars have thus provided a much welcomed starting point for a broader Nordic collaboration. (Author)

  17. In-situ-gamma ray spectrometry for measurements of environmental radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Winkelmann, I

    1994-12-31

    A detailed description of the method is presented. The range of application is shown. The calibration of the in-situ gamma ray spectrometer with a HPGe semiconductor detector and the evaluation of the spectra are described. A measuring time of about 15-30 min is sufficient to determine the specific natural and man-made radioactivity of the soil of some ten Bq/m{sup 2}. The results of soil contamination measurements in Germany after the Chernobyl accident are reported. A total of 22 nuclides are detected. The measured contamination for the first days after the accident was as follows: {sup 132}Te/{sup 132}I - 100 kBq/m{sup 2}, and {sup 131}I - 70 kBq/m{sup 2}. 6 figs., 4 tabs. (orig.).

  18. Coincidence gamma-ray spectrometry

    DEFF Research Database (Denmark)

    Markovic, Nikola; Roos, Per; Nielsen, Sven Poul

    2017-01-01

    Gamma-ray spectrometry with high-purity germanium (HPGe) detectors is often the technique of choice in an environmental radioactivity laboratory. When measuring environmental samples associated activities are usually low so an important parameter that describes the performance of the spectrometer...... for a nuclide of interest is the minimum detectable activity (MDA). There are many ways for lowering the MDAs in gamma spectrometry. Recently, developments of fast and compact digital acquisition systems have led to growing number of multiple HPGe detector spectrometers. In these applications all detected...

  19. GammaSem Proceedings - A Nordic seminar for users of gamma spectrometry

    International Nuclear Information System (INIS)

    Nunez, P.; Klemola, S.; Nielsen, Sven P.; Palsson, S.E.; Israelson, C.

    2010-03-01

    The project GammaSem was proposed to provide a forum for discussions and sharing of information on practical issues concerning gamma spectrometry and to establish a network of users of gamma spectrometry in the Nordic countries, thereby strengthening the collaboration and improving all participants' competence in practical gamma spectrometry. The seminars' focus was practical challenges met by the users themselves, rather than theoretical matters. Scientists and users of gamma spectrometry from all five Nordic countries were invited to the seminar, as well as scientist from the Baltic countries. A total of 75 people participated; representing 34 different universities, commercial companies, research institutes and also all Nordic authorities. During the seminar several key issues for follow-up were identified and working groups for addressing the identified problems were established. The working groups were: 1) Uncertainties and detections of limits 2) True summing coincidence 3) Monte Carlo simulations and efficiency transfer 4) Absorption (density corrections and geometries) 5) Mobile gamma spectrometry systems 6) Nuclear forensics (on special samples and special parts of the spectra). The identified topics will form the basis for the agenda of the next seminar in 2010. There, the different working groups will be invited to present their ideas/solutions to the relevant problems. (author)

  20. GammaSem Proceedings - A Nordic seminar for users of gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, P. (ed.) (Institute for Energy Technology (IFE) (Norway)); Klemola, S. (Radiation and Nuclear Safety Authority (STUK) (Finland)); Nielsen, Sven P. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy. Roskilde (Denmark)); Palsson, S.E. (Icelandic Radiation Safety Authority (IS)); Israelson, C. (National Institute of Radiation Protection (Denmark))

    2010-03-15

    The project GammaSem was proposed to provide a forum for discussions and sharing of information on practical issues concerning gamma spectrometry and to establish a network of users of gamma spectrometry in the Nordic countries, thereby strengthening the collaboration and improving all participants' competence in practical gamma spectrometry. The seminars' focus was practical challenges met by the users themselves, rather than theoretical matters. Scientists and users of gamma spectrometry from all five Nordic countries were invited to the seminar, as well as scientist from the Baltic countries. A total of 75 people participated; representing 34 different universities, commercial companies, research institutes and also all Nordic authorities. During the seminar several key issues for follow-up were identified and working groups for addressing the identified problems were established. The working groups were: 1) Uncertainties and detections of limits 2) True summing coincidence 3) Monte Carlo simulations and efficiency transfer 4) Absorption (density corrections and geometries) 5) Mobile gamma spectrometry systems 6) Nuclear forensics (on special samples and special parts of the spectra). The identified topics will form the basis for the agenda of the next seminar in 2010. There, the different working groups will be invited to present their ideas/solutions to the relevant problems. (author)

  1. In-situ high-resolution gamma-spectrometric survey of burial ground-monitoring wells

    International Nuclear Information System (INIS)

    Bowman, W.W.

    1981-09-01

    In situ high resolution gamma-ray spectrometry with an intrinsic germanium detector assembly of special design surveyed the burial ground monitoring wells to locate and identify gamma emitters that may have migrated from the burial trenches toward the water table. Gamma-ray spectra were acquired as a function of depth in each well and recorded on magnetic tape. These spectra were reduced by a series of computer programs to produce count rate versus depth profiles for natural and man-made activities. The original spectra and the profiles have been archived on magnetic tape for comparison with similar future surveys. Large amounts of man-made activities were observed in some of the burial trenches; however, below the trench bottoms, only very low but detectable amounts of 60 Co and 137 Cs were observed in eleven wells. The highest level of man-made gamma activity observed below the trench bottoms has a count rate roughly equal to that observed for uranium daughter activities which are natural to the subsoil

  2. Handbook on Mobile Gamma-ray Spectrometry

    DEFF Research Database (Denmark)

    Aage, Helle Karina; Korsbech, Uffe C C

    2003-01-01

    Basic physics and mathematics for Airborne and Car-borne Gamma-ray Spectrometry supplemented with practical examples and methods for advanced data processing......Basic physics and mathematics for Airborne and Car-borne Gamma-ray Spectrometry supplemented with practical examples and methods for advanced data processing...

  3. In situ measurements in an immerged environment of ambient gamma radiation activity and associated spectrometry

    International Nuclear Information System (INIS)

    Metivier, J.

    1993-01-01

    A set of site measurement devices composed of an ictometer, an air ionization chamber and a gamma ray spectrometry chain was modified so that the type of measurements could be carried out in an immerged environment with the equipment lying on the sediments of the prospected area. The different detectors can be controlled-and the data stored in a portable and autonomous 'PC' microcomputer from a light craft

  4. Applied gamma-ray spectrometry

    CERN Document Server

    Dams, R; Crouthamel, Carl E

    1970-01-01

    Applied Gamma-Ray Spectrometry covers real life application of the gamma-ray and the devices used in their experimental studies. This book is organized into 9 chapters, and starts with discussions of the various decay processes, the possible interaction mechanisms of gamma radiation with matter, and the intrinsic and extrinsic variables, which affect the observed gamma-ray and X-ray spectra. The subsequent chapters deal with the properties and fabrication of scintillation detectors, semiconductor detectors, and proportional gas counters. These chapters present some of the most widely utilized

  5. Gamma-ray spectrometry applied to down-hole logging

    International Nuclear Information System (INIS)

    Dumesnil, P.; Umiastowsky, K.

    1983-11-01

    Gamma-ray spectrometry permits to improve the accuracy of natural gamma, gamma-gamma and neutron-gamma geophysical measurements. The probe developed at Centre d'Etudes Nucleaires de Saclay allows down-hole gamma-ray spectrometry. Among others, this probe can be applied to the uranium content determination by selective natural gamma method, down-hole determination of the ash content in the coal by gamma-gamma selective method and elemental analysis by neutron-gamma method. For the calibration and an exact interpretation of the measurements it is important to know the gamma-ray and neutron characteristics of the different kinds of rocks considered as probabilistic variables

  6. Urban gamma spectrometry. Report 2

    Energy Technology Data Exchange (ETDEWEB)

    Aage, H.K. (Technical Univ. of Denmark, Kgs. Lyngby (Denmark)); Kuukankorpi, S.; Moring, M.; Smolander, P.; Toivonen, H. (Radiation and Nuclear Safety Authority, Helsinki (Finland))

    2009-06-15

    Urban gamma spectrometry has been given only minor attention with the focus being on rural gamma spectrometry. However, in recent years the Nordic emergency management authorities have turned focus towards border control and lost or stolen sources. Gamma spectra measured in urban areas are characterized by a wide variety of spectrum shapes and very fast changes in environmental background. In 2004 a Danish CGS (Carborne Gamma Spectrometry) survey took place in Copenhagen. It was found that gamma spectrometry in urban areas is far more complicated to interpret than had previously been thought and a new method 'Fitting with Spectral Components', FSC, based on NASVD, was tested with some success. In Finland, a database 'LINSSI' has been developed for spectral data management. In CGS search mode a 'peak hypothesis test' is applied to the measured spectra. This system was tested during the Helsinki 2005 Athletics World Championship and it provides fast and reliable automated alarms for intermediate and high level signals. In Sweden mobile detector systems are used for border controls and problems are encountered when making measurement in harbour, container areas. The methods for handling data and for interpretation of urban gamma spectrometry measurements were compared and tested on the same data sets from Copenhagen and Helsinki. Software tools were developed for converting data between the Finnish LINSSI database and the binary file formats used in Denmark and Sweden. The Processing methods used at DTU and STUK have different goals. The ASSS and FSC methods are designed to optimize the overall detection capability of the system, while sacrificing speed, usability and to a certain level robustness. These methods cannot always be used for real time analysis. The Peak Significance method is designed to give robust alarms in real time, while sacrificing some of the detection capability. Thus these methods are not interchangeable, but rather

  7. Urban gamma spectrometry. Report 2

    International Nuclear Information System (INIS)

    Aage, H.K.; Kuukankorpi, S.; Moring, M.; Smolander, P.; Toivonen, H.

    2009-06-01

    Urban gamma spectrometry has been given only minor attention with the focus being on rural gamma spectrometry. However, in recent years the Nordic emergency management authorities have turned focus towards border control and lost or stolen sources. Gamma spectra measured in urban areas are characterized by a wide variety of spectrum shapes and very fast changes in environmental background. In 2004 a Danish CGS (Carborne Gamma Spectrometry) survey took place in Copenhagen. It was found that gamma spectrometry in urban areas is far more complicated to interpret than had previously been thought and a new method 'Fitting with Spectral Components', FSC, based on NASVD, was tested with some success. In Finland, a database 'LINSSI' has been developed for spectral data management. In CGS search mode a 'peak hypothesis test' is applied to the measured spectra. This system was tested during the Helsinki 2005 Athletics World Championship and it provides fast and reliable automated alarms for intermediate and high level signals. In Sweden mobile detector systems are used for border controls and problems are encountered when making measurement in harbour, container areas. The methods for handling data and for interpretation of urban gamma spectrometry measurements were compared and tested on the same data sets from Copenhagen and Helsinki. Software tools were developed for converting data between the Finnish LINSSI database and the binary file formats used in Denmark and Sweden. The Processing methods used at DTU and STUK have different goals. The ASSS and FSC methods are designed to optimize the overall detection capability of the system, while sacrificing speed, usability and to a certain level robustness. These methods cannot always be used for real time analysis. The Peak Significance method is designed to give robust alarms in real time, while sacrificing some of the detection capability. Thus these methods are not interchangeable, but rather complementary. An ideal system

  8. Gamma spectrometry of infinite 4Π geometry

    International Nuclear Information System (INIS)

    Nordemann, D.J.R.

    1987-07-01

    Owing to the weak absorption og gamma radiation by matter, gamma-ray spectrometry may be applied to samples of great volume. A very interesting case is that of the gamma-ray spectrometry applied with 4Π geometry around the detector on a sample assumed to be of infinite extension. The determination of suitable efficiencies allows this method to be quantitative. (author) [pt

  9. Application of gamma spectrometry survey and discussion on data processing

    International Nuclear Information System (INIS)

    Li Ji'an; He Jianguo

    2008-01-01

    This paper analyzed and discussed the different opinions about the measured parameters of gamma spectrometry data, introduced the effect of gamma spectrometry survey to the search for sandstone type uranium deposit. The author believes that it is very necessary to perform some ground gamma spectrometry survey and enforce the development and application of airborne radiometric data so as to carry out the role of gamma spectrometry in the exploration of sandstone type uranium deposit. (authors)

  10. Rapid in situ gamma spectrometric determination of fallout radioactivity in the environment. Progress report

    International Nuclear Information System (INIS)

    Zombori, Peter

    1995-01-01

    The main aim of the present CRP is to identify the existing analytical methods and develop new ones, if possible, which provide rapid, reliable, and detailed information on the radioactive contamination of the environment after a major nuclear accident. Gamma spectrometry has long been regarded as one of the most applicable radioanalytical techniques but its use for environmental studies requires some further considerations. There are two possible approaches to measure environmental radioactivity: (a) taking samples of the different environmental media and measuring them in a laboratory or (b) taking the spectrometer to the place of interest and making in situ measurements. In the former case sampling is a crucial factor hindering the rapid analysis while the latter case is not always reliable due to the problems and uncertainties of the measurement interpretation. The application of in situ gamma spectrometry for the determination of environmental radioactivity has become increasingly attractive since the advent of the high resolution semiconductor gamma detectors, especially, more recently, portable high purity Ge diodes (HpGe). The applicability of this technique was very well proved after the Chernobyl reactor accident when in situ spectrometry played an important role in the rapid evaluation of the fall-out situation. Our measurements provided information on the amount and composition of the radioactive contamination of the ground surface already in the first hours. These measurements enabled us to predict the time variation of the environmental radioactivity after the stabilization of the situation. The portability of the system was an important factor in performing a rapid and efficient survey in different parts of the country. A serious disadvantage of this method is, however, that it requires some knowledge about the radionuclide distribution in the soil, which is normally determined by tedious and time consuming sample analysis of the different soil

  11. Mapping of depleted uranium with in situ spectrometry and soil samples

    International Nuclear Information System (INIS)

    Shebell, P.; Reginatto, M.; Monetti, M.; Faller, S.; Davis, L.

    1999-01-01

    Depleted uranium (DU) has been developed in the past two decades as a highly effective material for armor penetrating rounds and vehicle shielding. There is now a growing interest in the defense community to determine the presence and extent of DU contamination quickly and with a minimum amount of intrusive sampling. We report on a new approach using deconvolution techniques to quantitatively map DU contamination in surface soil. This approach combines data from soil samples with data from in situ gamma-ray spectrometry measurements to produce an accurate and detailed map of DU contamination. Results of a field survey at the Aberdeen Proving Ground are presented. (author)

  12. Aircraft gamma-ray spectrometry in snow-water equivalent measurement

    Energy Technology Data Exchange (ETDEWEB)

    Kuittinen, R; Vironmaeki, J

    1979-01-01

    During the winter periods of 1976 to 1977 and 1977 to 1978, the Hydrological Office at the National Boards of Waters and the Geological Survey of Finland carried out a joint study to evaluate usefulness of gamma-ray spectrometry in snowwater equivalent measurement. A multichannel gamma-ray spectrometry was fitted out in a DC-3 aircraft. Fourteen snow courses were operated using gravimetric method and gamma-ray method. The snow courses were located in southern Finland in forest, swamp and agricultural land. The results show that the gamma ray method can be considered suitable for use in Finnish conditions and the accuracy of the gamma-ray method is almost of the same magnitude of the accuracy of the gravimetric method.

  13. Environmental monitoring with in-situ gamma spectrometer; Umweltueberwachung mit in-situ-Gamma-Spektrometer

    Energy Technology Data Exchange (ETDEWEB)

    Reinhardt, S. [ENVINET GmbH, Haar (Germany)

    2014-01-20

    The in-situ gamma spectroscopy allows large area and continuous monitoring of the radio nuclides and there composition in the environment. In comparison to the gamma dose rate measurement the additional spectral information gives the possibility for a quick and effective action in the case of a man-made radiation exposition in the environment. The knowledge respectively localization of the possible nuclides, which a responsible for the increased dose rate, supports responsible organization in the quick identification of the situation, definition of the actions and tracking of the temporal and local process of the radiation exposition. Due to dedicate actions the risk for people and environment is reduced.

  14. On response operator in semiconductor gamma ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Krnac, S [Slovak Technical Univ., Bratislava (Slovakia); Povinec, P [International Atomic Energy Agency, Monaco (Monaco). MEL; Ragan, R [Inst. of Preventive and Clinical Medicine, Bratislava (Slovakia)

    1996-12-31

    Some results of the scaling confirmation factor analysis (SCFA) application in semiconductor gamma-ray spectrometry presented in this contribution points out to a new ground for evaluation the gamma-ray spectra. This whole-spectrum processing approach considerably increases detection sensitivity, especially, if significant interferences being present in the measured spectrum. Precision of the SCFA method is determined by choice of a sufficient number of suitable calibration gamma-ray sources in the energy region of interest, by setting up an acceptable latent hypothesis and by chosen experimental quantification of spectra. The SCFA method is very advantageous to use, for instance, in ultra low-level gamma-spectrometry where counting rates in full energy peaks are extremely low as compared with background interferences. It enables to increase of the sensitivity by the 5-10 times in comparison with the traditional full energy peak net area method (J.K.). 1 fig., 2 tabs., 6 refs.

  15. On response operator in semiconductor gamma ray spectrometry

    International Nuclear Information System (INIS)

    Krnac, S.; Povinec, P.

    1995-01-01

    Some results of the scaling confirmation factor analysis (SCFA) application in semiconductor gamma-ray spectrometry presented in this contribution points out to a new ground for evaluation the gamma-ray spectra. This whole-spectrum processing approach considerably increases detection sensitivity, especially, if significant interferences being present in the measured spectrum. Precision of the SCFA method is determined by choice of a sufficient number of suitable calibration gamma-ray sources in the energy region of interest, by setting up an acceptable latent hypothesis and by chosen experimental quantification of spectra. The SCFA method is very advantageous to use, for instance, in ultra low-level gamma-spectrometry where counting rates in full energy peaks are extremely low as compared with background interferences. It enables to increase of the sensitivity by the 5-10 times in comparison with the traditional full energy peak net area method (J.K.). 1 fig., 2 tabs., 6 refs

  16. Programmer for automatic gamma spectrometry; Ordonnateur de sequence pour spectrometrie gamma automatique

    Energy Technology Data Exchange (ETDEWEB)

    Romanetti, R [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1968-04-01

    With this apparatus, which is constructed of logical integrated circuits, it is possible both to synchronize an automatic gamma spectrometry assembly and to record the spectra on punched cards. An IBM terminal will make it possible with the help of analysis by the least squares method and by a direct dialogue with an IBM 360 computer to obtain analytical results almost instantaneously. (author) [French] Cet appareil, realise en circuits integres logiques, permet d'une part de synchroniser un ensemble automatique de spectrometrie gamma et d'autre part d'enregistrer les spectres sur cartes perforees. Un terminal IBM permettra, a l'aide d'un programme d'analyse par la methode des moindres carres et par un dialogue direct avec un ordinateur IBM 360, de disposer presque intanstanement des resultats des analyses. (auteur)

  17. Constrains in gamma spectrometry analysis of fallout 137Cs in coastal marine environment of Arabian sea in India

    International Nuclear Information System (INIS)

    Sartandel, S.J.; Jha, S.K.; Puranik, V.D.

    2012-01-01

    In this study, an accurate faster gamma spectrometry method for measuring the low level activity concentrations of 137 Cs using in situ pre-concentration technique on copper ferrocyanide cartridge was standardized. Due to unavailability of reference standard in the copper ferrocyanide matrix, efficiency calibration curves were plotted using RGU and RGTh reference standards. To harmonize the difference in density of standard and sample the required density correction factors for photo peak efficiency were generated. The in situ pre-concentration technique followed by gamma-ray spectrometry was applied for activity determination in surface seawater from eight locations in the coastal marine environment of Arabian Sea. The mean activity concentration of 137 Cs ranged between 0.71 and 0.91 Bq/m 3 . Higher activity concentrations were observed at location with latitude, longitude of 21.6 deg N, 69.57 deg E as compared to concentration observed at location with latitude, longitude 16.98 deg N, 73.25 deg E. The observed concentrations were found to be in range of data reported in Asia-Pacific Marine radioactive database (ASPARMARD). The results will fill up the gaps in the existing database. The generated data will be useful for monitoring fresh input of anthropogenic radionuclide into coastal marine environment for post Fukushima environmental assessment. (author)

  18. Automatic gamma spectrometry analytical apparatus

    International Nuclear Information System (INIS)

    Lamargot, J.-P.; Wanin, Maurice.

    1980-01-01

    This invention falls within the area of quantitative or semi-quantitative analysis by gamma spectrometry and particularly refers to a device for bringing the samples into the counting position. The purpose of this invention is precisely to provide an automatic apparatus specifically adapted to the analysis of hard gamma radiations. To this effect, the invention relates to a gamma spectrometry analytical device comprising a lead containment, a detector of which the sensitive part is located inside the containment and additionally comprising a transfer system for bringing the analyzed samples in succession to a counting position inside the containment above the detector. A feed compartment enables the samples to be brought in turn one by one on to the transfer system through a duct connecting the compartment to the transfer system. Sequential systems for the coordinated forward feed of the samples in the compartment and the transfer system complete this device [fr

  19. Initial Gamma Spectrometry Examination of the AGR-3/4 Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Harp, Jason M.; Demkowicz, Paul A.; Stempien, John D.

    2016-11-01

    The initial results from gamma spectrometry examination of the different components from the combined third and fourth US Advanced Gas Reactor Fuel Development TRISO-coated particle fuel irradiation tests (AGR-3/4) have been analyzed. This experiment was designed to provide information about in-pile fission product migration. In each of the 12 capsules, a single stack of four compacts with designed-to-fail particles surrounded by two graphitic diffusion rings (inner and outer) and a graphite sink were irradiated in the Idaho National Laboratory’s Advanced Test Reactor. Gamma spectrometry has been used to evaluate the gamma-emitting fission product inventory of compacts from the irradiation and evaluate the burnup of these compacts based on the activity of the radioactive cesium isotopes (Cs-134 and Cs-137) in the compacts. Burnup from gamma spectrometry compares well with predicted burnup from simulations. Additionally, inner and outer rings were also examined by gamma spectrometry both to evaluate the fission product inventory and the distribution of gamma-emitting fission products within the rings using gamma emission computed tomography. The cesium inventory of the scanned rings compares acceptably well with the expected inventory from fission product transport modeling. The inventory of the graphite fission product sinks is also being evaluated by gamma spectrometry.

  20. Air kerma rate estimation by means of in-situ gamma spectrometry: A Bayesian approach

    International Nuclear Information System (INIS)

    Cabal, Gonzalo; Kluson, Jaroslav

    2008-01-01

    Full text: Bayesian inference is used to determine the Air Kerma Rate based on a set of in situ environmental gamma spectra measurements performed with a NaI(Tl) scintillation detector. A natural advantage of such approach is the possibility to quantify uncertainty not only in the Air Kerma Rate estimation but also for the gamma spectra which is unfolded within the procedure. The measurements were performed using a 3'' x 3'' NaI(Tl) scintillation detector. The response matrices of such detection system were calculated using a Monte Carlo code. For the calculations of the spectra as well as the Air Kerma Rate the WinBugs program was used. WinBugs is a dedicated software for Bayesian inference using Monte Carlo Markov chain methods (MCMC). The results of such calculations are shown and compared with other non-Bayesian approachs such as the Scofield-Gold iterative method and the Maximum Entropy Method

  1. Metrological characterization of the numerical system Adonis for gamma spectrometry; Caracterisation metrologique du systeme de spectrometrie gamma numerique Adonis

    Energy Technology Data Exchange (ETDEWEB)

    Plagnard, J.; Morel, J.; Tran Tuan, A

    2005-07-01

    In gamma spectrometry, new acquisition systems based on digital processing of the signals are now available on the market. In order to determine their performances at high count rates, The CEA-LNHB (Commissariat a l'Energie Atomique - Laboratoire National Henri Becquerel) has tested several of these equipments.. These tests have clearly shown that the performances announced by the manufacturers were generally not met. At this point, it was interesting to include in these tests, the system ADONIS (Atelier de Developpement Numerique pour l'Instrumentation en Spectrometrie), which is the new gamma spectrometry system, developed by the CEA-SIAR (Service d'Instrumentation et d'Application des Rayonnements). (authors)

  2. An automatic sample changer for gamma spectrometry

    International Nuclear Information System (INIS)

    Andrews, D.J.

    1984-01-01

    An automatic sample changer for gamma spectrometry is described which is designed for large-volume, low radioactivity environmental samples of various sizes up to maximum dimensions 100 mm diameter x 60 mm high. The sample changer is suitable for use with most existing gamma spectrometry systems which utilize GeLi or NaI detectors in vertical mode, in conjunction with a pulse height analyzer having auto-cycle and suitable data output facilities; it is linked to a Nuclear Data ND 6620 computer-based analysis system. (U.K.)

  3. Guidelines for radioelement mapping using gamma ray spectrometry data

    International Nuclear Information System (INIS)

    2003-07-01

    The purpose of the report is to provide an up-to-date review on the use of gamma ray spectrometry for radioelement mapping and, where appropriate, provide guidelines on the correct application of the method. It is a useful training guide for those new to the method. It gives a broad coverage of all aspects of the gamma ray method and provides a comprehensive list of references. The report gives an overview of the theoretical background to radioactivity and the gamma ray spectrometric method followed by a review of the application of the method to mapping the radiation environment. A brief outline is presented of the principles of radioactivity, the interaction of gamma rays with matter, instrumentation applied to the measurement of gamma rays, and the quantities and units in contemporary use in gamma ray spectrometry. This is followed by a review of the fundamentals of gamma ray spectrometry, and its application to ground and airborne mapping. Covered are also all aspects of the calibration and data processing procedures required for estimating the ground concentrations of the radioelements. The procedures required for the recovery of older survey data are also presented as well as an overview of data presentation and integration for mapping applications

  4. Some deficiencies and solutions in gamma ray spectrometry

    International Nuclear Information System (INIS)

    Westmeier, W.

    1998-01-01

    A number of problems in high-resolution gamma ray spectrometry as well as some deficiencies of existing computer programs for the quantitative evaluation of spectra are discussed and some practical solutions are proposed. (author)

  5. In-situ gamma spectroscopic measurement of natural waters in Bulgaria

    International Nuclear Information System (INIS)

    Manushev, B.; Mandzhukov, I.; Tsankov, L.; Boshkova, T.; Gurev, V.; Mandzhukova, B.; Kozhukharov, I.; Grozev, G.

    1983-01-01

    In-situ gamma spectrometric measurements are carried out to record differences higher than the errors of measurement in the gamma-field spectra in various basins in Bulgaria - two high mountain lakes, dam and the Black sea. A standard scintillation gamma spectrometer, consisting of a scintillation detector ND-424 type, a channel analyzer NP-424 and a 128 channel Al-128 type analyzer, has been used. The sensitivity of the procedure used is sufficient to detect the transfer of nuclides by dissolution from rocks, forming the bottom and the water-collecting region of the water basin. The advancement of the experimental techniques defines the future use of the procedure. In-situ gamma spectrometric determination may be used in cases of continuous and automated control of the radiation purity of the cooling water in atomic power plants or the water basins located close to such plants and of radioactive contamination of the sea and ocean water

  6. Execution of a cooperative test by means of 'in-situ-gamma spectrometry' using HP-germanium detectors

    International Nuclear Information System (INIS)

    Steger, F.; Lovranich, E.; Urbanich, E.; Streit, S.

    1995-06-01

    A cooperative test was carried out in Salzburg, Austria, in order to determine the activity of Cs-137 and other radio nuclides from the Tschernobyl fallout 1986 and from tests of nuclear weapons in the 1960s. 24 groups from 9 countries of Europe took part. The measurements were performed by means of gamma spectrometry using HP-germanium detectors. Most of the groups had excellent results. The groups became acquainted with each other. The personal contact makes it possible to get information quickly in case of accidents of nuclear power stations in the neighbourhood of Austria

  7. In Situ Analytical Characterization of Contaminated Sites Using Nuclear Spectrometry Techniques. Review of Methodologies and Measurements

    International Nuclear Information System (INIS)

    2017-01-01

    Past and current human activities can result in the contamination of sites by radionuclides and heavy metals. The sources of contamination are various. The most important sources for radionuclide release include global fallout from nuclear testing, nuclear and radiological accidents, waste production from nuclear facilities, and activities involving naturally occurring radioactive material (NORM). Contamination of the environment by heavy metals mainly originates from industrial applications and mineralogical background concentration. Contamination of sites by radionuclides and heavy metals can present a risk to people and the environment. Therefore, the estimation of the contamination level and the identification of the source constitute important information for the national authorities with the responsibility to protect people and the environment from adverse health effects. In situ analytical techniques based on nuclear spectrometry are important tools for the characterization of contaminated sites. Much progress has been made in the design and implementation of portable systems for efficient and effective monitoring of radioactivity and heavy metals in the environment directly on-site. Accordingly, the IAEA organized a Technical Meeting to review the current status and trends of various applications of in situ nuclear spectrometry techniques for analytical characterization of contaminated sites and to support Member States in their national environmental monitoring programmes applying portable instrumentation. This publication represents a comprehensive review of the in situ gamma ray spectrometry and field portable X ray fluorescence analysis techniques for the characterization of contaminated sites. It includes papers on the use of these techniques, which provide useful background information for conducting similar studies, in the following Member States: Argentina, Australia, Brazil, Czech Republic, Egypt, France, Greece, Hungary, Italy, Lithuania

  8. Measurements of uranium enrichment by four techniques of gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Tojo, Takao

    1983-12-01

    Measurements of uranium enrichment with the uses of the LMRI (France) UO 2 standards have been made by four techniques of gamma-ray spectrometry, in order to examine measurement characteristics of each technique. The following results were obtained by the three techniques based on the direct determination of the peak area of the 186-keV gamma-rays from 235 U, when the standard sample of 6.297 a/o was used for measuring enrichments ranging from 1.4 a/o to 9.6 a/o ; (i) In a LEPS HP Ge gamma-ray spectrometry, standard deviation of the measured enrichments from the certified ones was 1.4 %, (ii) in a Ge(Li) gamma-ray spectrometry, the standard deviation was 2.0 %, (iii) in a NaI(Tl) gamma-ray spectrometry, the standard deviation was 1.2 %. In the fourth technique, the method of multiple single-channel analyzers, enrichments of 1.4 - 9.6 a/o were measured in the standard deviation of 0.51 %, when the most suitable pairs of standard samples were used for each sample. A part of sources of systematic errors which were caused by each technique adopted was revealed throughout the measurements. And also, it was recognized that the LMRI's values of enrichment were certified precisely, and the UO 2 standards were very useful for enrichment measurements in the four techniques of gamma-ray spectrometry used here. (author)

  9. Recent progress in low-level gamma imaging

    International Nuclear Information System (INIS)

    Mahe, C.; Girones, Ph.; Lamadie, F.; Le Goaller, C.

    2007-01-01

    The CEA's Aladin gamma imaging system has been operated successfully for several years in nuclear plants and during decommissioning projects with additional tools such as gamma spectrometry detectors and dose rate probes. The radiological information supplied by these devices is becoming increasingly useful for establishing robust and optimized decommissioning scenarios. Recent technical improvements allow this gamma imaging system to be operated in low-level applications and with shorter acquisition times suitable for decommissioning projects. The compact portable system can be used in places inaccessible to operators. It is quick and easy to implement, notably for onsite component characterization. Feasibility trials and in situ measurements were recently carried out under low-level conditions, mainly on waste packages and glove boxes for decommissioning projects. This paper describes recent low-level in situ applications. These characterization campaigns mainly concerned gamma emitters with γ energy < 700 keV. In many cases, the localization of hot spots by gamma camera was confirmed by additional measurements such as dose rate mapping and gamma spectrometry measurements. These complementary techniques associated with advanced calculation codes (MCNP, Mercure 6.2, Visiplan and Siren) offer a mobile and compact tool for specific assessment of waste packages and glove boxes. (authors)

  10. Aircraft gamma-ray spectrometry in snow-water equivalent measurement

    International Nuclear Information System (INIS)

    Kuittinen, R.; Vironmaeki, J.

    1979-01-01

    During the winter periods 1976-1977 and 1977-1978 the Hydrological Office at the National Board of Waters and the Geological Survey of Finland carried out a joint study to evaluate usefuluess of gamma-ray spectrometry in snow-water equivalent measurement. A multichannel gamma-ray spectrometer was fitted in a DC-3 aircraft. Fourteen snow courses were operated using both the gravimetric method and the gamma-ray method. The snow courses were located in southern Finland in forest, swamp and agricultural land. The results shows that the gamma ray method can be considered suitable for use in Finnish conditions and the accuracy of the gamma-ray method is almost of the same magnitude as the accuracy of the gravimetric method. (Auth.)

  11. Aircraft gamma-ray spectrometry in snow-water equivalent measurement

    Energy Technology Data Exchange (ETDEWEB)

    Kuittinen, R [National Board of Waters (Finland); Vironmaeki, J [Geological Survey of Finland

    1979-01-01

    During the winter periods 1976-1977 and 1977-1978 the Hydrological Office at the National Board of Waters and the Geological Survey of Finland carried out a joint study to evaluate usefuluess of gamma-ray spectrometry in snow-water equivalent measurement. A multichannel gamma-ray spectrometer was fitted in a DC-3 aircraft. Fourteen snow courses were operated using both the gravimetric method and the gamma-ray method. The snow courses were located in southern Finland in forest, swamp and agricultural land. The results shows that the gamma ray method can be considered suitable for use in Finnish conditions and the accuracy of the gamma-ray method is almost of the same magnitude as the accuracy of the gravimetric method.

  12. Gamma ray spectrometry: applications in uranium prospecting and environment

    International Nuclear Information System (INIS)

    Lopez, Luis E.

    1999-01-01

    The experience in the use of gamma spectrometry for uranium prospecting and for the determination of natural radiation background is described. The basic principles of the techniques are also given. (author)

  13. Gamma and X 93 spectrometry

    International Nuclear Information System (INIS)

    1994-05-01

    The Meetings of Gamma and X 93 Spectrometry were held on 12-14 October 1993. The symposium was organized into six sessions: Instrumentation development, Nuclear matter measurement, Method and calibration, Medical applications, Environment survey (radioactive traces measurement), other applications (spent fuels analysis, various techniques). Separate abstracts were prepared for all the papers in this volume. (TEC)

  14. Ex-situ and in-situ observations of the effects of gamma radiation on lithium ion battery performance

    Science.gov (United States)

    Tan, Chuting; Bashian, Nicholas H.; Hemmelgarn, Chase W.; Thio, Wesley J.; Lyons, Daniel J.; Zheng, Yuan F.; Cao, Lei R.; Co, Anne C.

    2017-07-01

    Radiation effects induced by gamma rays on battery performance were investigated by measuring the capacity and resistance of a series of battery coin cells in-situ directly under gamma radiation and ex-situ. An experimental setup was developed to charge and discharge batteries directly under gamma radiation, equipped with precise temperature control, at The Ohio State University Nuclear Reactor Lab. Latent effects induced by gamma radiation on battery components directly influence their performance. Charge and discharge capacity and overall resistance throughout a time span of several weeks post irradiation were monitored and compared to control groups. It was found that exposure to gamma radiation does not significantly alter the available capacity and the overall cell resistance immediately, however, battery performance significantly decreases with time post irradiation. Also, batteries exposed to a higher cumulative dose showed close-to-zero capacity at two-week post irradiation.

  15. Determination of Pu isotopic composition and 241Am by high resolution gamma spectrometry on solid samples

    International Nuclear Information System (INIS)

    Sarkar, Arnab; Paul, Sumana; Aggarwal, Suresh K.; Tomar, Bhupendra S.

    2011-08-01

    The present report gives a detailed account of the development of non-destructive assay technique using high resolution gamma-ray spectrometry (HRGS) for determination of plutonium (Pu) isotopic composition and the 241 Am content in solid Pu samples. Energy range 120-420 keV was used in this study. The methodology involves in situ relative efficiency calibration during the measurement process itself, to reduce the errors and increase the reliability of the method. Twenty solid Pu samples of power reactor and research reactor grade were analyzed by this method and the results were compared with those obtained by thermal ionization mass spectrometry. The accuracy of the final results depends strongly upon the accuracy of the available nuclear data (decay constant, gamma abundance etc.). MATLAB based programme was written to perform the analysis. A counting time of 4 hour was chosen for achieving good statistics on the results for samples having 100-200 mg of Pu. The attainable accuracy is found to be 0.5-1% for the fissile isotopes ( 239 Pu + 241 Pu) and 5-10% for 241 Am content. (author)

  16. The advantage of using the henry straight line in {gamma} spectrometry (1963); Interet de l'utilisation de la droite de henry en spectrometrie {gamma} (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Jockey, [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    The Henry construction is a convenient way to interpret the total absorption peaks in gamma spectrometry by exploiting their statistical significance. It is so possible to determine graphically, and accurately, such values as: - position of the peak - resolution, etc. The main practical applications are considered. (author) [French] La construction de la droite de Henry fournit un moyen commode d'interpreter les pics d'absorption totale en spectrometrie gamma en exploitant leur signification statistique, il est ainsi possible de determiner graphiquement, avec precision, des notions telles que: - position du pic - resolution, etc. Les principales applications pratiques sont envisagees. (auteur)

  17. An analysis of nuclear fuel burnup in the AGR-1 TRISO fuel experiment using gamma spectrometry, mass spectrometry, and computational simulation techniques

    International Nuclear Information System (INIS)

    Harp, Jason M.; Demkowicz, Paul A.; Winston, Philip L.; Sterbentz, James W.

    2014-01-01

    Highlights: • The burnup of irradiated AGR-1 TRISO fuel was analyzed using gamma spectrometry. • The burnup of irradiated AGR-1 TRISO fuel was also analyzed using mass spectrometry. • Agreement between experimental results and neutron physics simulations was excellent. - Abstract: AGR-1 was the first in a series of experiments designed to test US TRISO fuel under high temperature gas-cooled reactor irradiation conditions. This experiment was irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) and is currently undergoing post-irradiation examination (PIE) at INL and Oak Ridge National Laboratory. One component of the AGR-1 PIE is the experimental evaluation of the burnup of the fuel by two separate techniques. Gamma spectrometry was used to non-destructively evaluate the burnup of all 72 of the TRISO fuel compacts that comprised the AGR-1 experiment. Two methods for evaluating burnup by gamma spectrometry were developed, one based on the Cs-137 activity and the other based on the ratio of Cs-134 and Cs-137 activities. Burnup values determined from both methods compared well with the values predicted from simulations. The highest measured burnup was 20.1% FIMA (fissions per initial heavy metal atom) for the direct method and 20.0% FIMA for the ratio method (compared to 19.56% FIMA from simulations). An advantage of the ratio method is that the burnup of the cylindrical fuel compacts can be determined in small (2.5 mm) axial increments and an axial burnup profile can be produced. Destructive chemical analysis by inductively coupled mass spectrometry (ICP-MS) was then performed on selected compacts that were representative of the expected range of fuel burnups in the experiment to compare with the burnup values determined by gamma spectrometry. The compacts analyzed by mass spectrometry had a burnup range of 19.3% FIMA to 10.7% FIMA. The mass spectrometry evaluation of burnup for the four compacts agreed well with the gamma

  18. The determination and use of radionuclide background in gamma spectrometry

    International Nuclear Information System (INIS)

    Zimmer, W.H.

    1986-01-01

    Background is the major component of gross photon peak area. Therefore, net area, nuclide activity, counting uncertainty, and limits of detection calculations are no better than the calculation of background. In this study, background in gamma spectrometry is explored in several of its aspects. Means are presented to reduce background. Standard practices are presented to be used in the acquisition of valid, relevant background data. Unified standard calculations with examples are presented in the use of background data to determine net count and counting uncertainty. L. A. Currie's latest calculations of Lower Limits of Detection (1) (LLD) as they apply to gamma spectrometry are reviewed. Finally, Maximum Undetected Activity (MUA), LLD, and Critical Level (CL) concepts and calculations are compared in sample spectra

  19. Quantitative radiological characterization of waste. Integration of gamma spectrometry and passive/active neutron assay

    Energy Technology Data Exchange (ETDEWEB)

    Simone, Gianluca; Mauro, Egidio; Gagliardi, Filippo; Gorello, Edoardo [Nucleco S.p.A., Rome (Italy)

    2016-06-15

    The radiological characterization of drums through Non-Destructive Assay (NDA) techniques commonly relies on gamma spectrometry. This paper introduces the procedure developed in Nucleco for the NDA radiological characterization of drums when the presence of Special Nuclear Material (SNM) is expected/observed. The procedure is based on the integration of a gamma spectrometry in SGS mode (Segmented Gamma Scanner) and a passive/active neutron assay. The application of this procedure is discussed on a real case of drums. The extension of the integration procedure to other gamma spectrometry systems is also discussed.

  20. Correction for sample self-absorption in activity determination by gamma spectrometry

    International Nuclear Information System (INIS)

    Galloway, R.B.

    1991-01-01

    Gamma ray spectrometry is a convenient method of determining the activity of the radioactive components in environmental samples. Commonly samples vary in gamma absorption or differ in absorption from the calibration standards available, so that accurate correction for self-absorption in the sample is essential. A versatile correction procedure is described. (orig.)

  1. Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966); Etude de la radioactivite artificielle du milieu marin par spectrometrie gamma (1962-1966)

    Energy Technology Data Exchange (ETDEWEB)

    Chesselet, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    The results described in this study are relative to the artificial radioactivity of such elements as zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 and praseodymium-144 which were present in the atmospheric fallout between 1962 and 1964, and their incidence in superficial marine waters. Various physical, chemical or biological processes are studied by a high sensitivity gamma ray spectrometry technic, using those radioelements as 'tracers'. The change of state in sea water of an important fraction (about 50 per cent) of the radioactive particles going into the soluble phase - this phenomenon was not expected for those radioelements - controls the processes of accumulation in the planktonic biomass and the diffusion towards deeper waters. On the other hand, an 'in situ' spectrometry method is described. It enables the direct measurement in the sea of very low concentrations of some gamma ray emitters. The application of this method has made possible to carry out numerous observations in the surface waters of the Western Mediterranean sea and in the Bay of Biscay. It is shown that the mixing depth is closely connected to the depth of the thermocline. An accumulation process at this level is observed. The diffusion coefficients are similar to the thermal turbulent coefficient. The existence during several months of 'compartments' is established for the surface waters of the Bay of Biscay. From the establishment of the budget of fall-out, a comparative study shows that the rate of radioactive fallout on the maritime zone considered is always two to three times higher than on the neighbouring continental regions. Several explanations of this phenomenon are discussed. (author) [French] Les resultats decrits dans cette etude concernent la radioactivite artificielle sous forme de zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 et praseodyme-144 apportee par la retombee atmospherique entre 1962 et 1964 et les

  2. Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966); Etude de la radioactivite artificielle du milieu marin par spectrometrie gamma (1962-1966)

    Energy Technology Data Exchange (ETDEWEB)

    Chesselet, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    The results described in this study are relative to the artificial radioactivity of such elements as zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 and praseodymium-144 which were present in the atmospheric fallout between 1962 and 1964, and their incidence in superficial marine waters. Various physical, chemical or biological processes are studied by a high sensitivity gamma ray spectrometry technic, using those radioelements as 'tracers'. The change of state in sea water of an important fraction (about 50 per cent) of the radioactive particles going into the soluble phase - this phenomenon was not expected for those radioelements - controls the processes of accumulation in the planktonic biomass and the diffusion towards deeper waters. On the other hand, an 'in situ' spectrometry method is described. It enables the direct measurement in the sea of very low concentrations of some gamma ray emitters. The application of this method has made possible to carry out numerous observations in the surface waters of the Western Mediterranean sea and in the Bay of Biscay. It is shown that the mixing depth is closely connected to the depth of the thermocline. An accumulation process at this level is observed. The diffusion coefficients are similar to the thermal turbulent coefficient. The existence during several months of 'compartments' is established for the surface waters of the Bay of Biscay. From the establishment of the budget of fall-out, a comparative study shows that the rate of radioactive fallout on the maritime zone considered is always two to three times higher than on the neighbouring continental regions. Several explanations of this phenomenon are discussed. (author) [French] Les resultats decrits dans cette etude concernent la radioactivite artificielle sous forme de zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 et praseodyme-144 apportee par la retombee

  3. Portable gamma-ray spectrometers and spectrometry systems

    International Nuclear Information System (INIS)

    Shebell, P.

    1999-01-01

    The current state-of-the-art in portable gamma-ray spectrometers and portable spectrometry systems is discussed. A comparison of detector performance and features of commercially available systems are summarised. Finally, several applications of portable systems are described. (author)

  4. Gamma ray spectrometry results from core samples collected for RESUME 95

    International Nuclear Information System (INIS)

    Sanderson, D.C.W.; Allyson, J.D.; Toivonen, H.; Honkamaa, T.

    1997-01-01

    Field sampling of an airfield at Vesivehmaa, near Vaeaeksy, Finland (Area I) was carried out between 26-29 May 1995, to establish the radionuclide deposition and inventory of Chernobyl derived 137 Cs, and natural radionuclides. The objective was to establish a common calibration site for in-situ and airborne gamma spectrometers, for Exercise RESUME 95 conducted in August 1995. The report presents the sampling details, handling and treatment. The analyses are discussed with particular emphasis given to 137 Ca, 134 Cs, 40 K, 214 Bi and 208 radionuclides, and the quantification of their respective deposition and inventories. The results have been used to estimate the effective concentrations of nuclides at the calibration site for in-situ and airborne gamma spectrometry, and the depth distribution. For 137 Cs the weighted mean activity per unit area takes on values of 50.7±5.2 kBq m -2 at 1 m ground clearance, 51.1±6.9 kBq m -2 at 50 m height and 47.9±8.5 kBq m -2 at 100 m. The similarity of these values confirms the suitability of the Vesivehmaa site for comparison of in-situ and airborne results despite variations of a factor of two between results from individual cores. The mean α/ρ value for 137 Cs in Area I is 0.77±0.10 cm 2 g -1 (relaxation mass per unit area, β 1.31±0.15 gcm -2 ). Additional soil sampling across parts of Area II (a 6x3 km area selected for mapping Chernobyl deposition) was carried out. The mean level of 137 Cs activity from these samples was 92.4±63 kBq m -2 , a sample taken near Laihansuo showing the largest value obtained at 172 kBq m -2 . (EG)

  5. Burnup determination of power reactor fuel elements by gamma spectrometry; Determination par spectrometrie {gamma} du taux d'irradiation des elements combustibles des reacteurs de puissance

    Energy Technology Data Exchange (ETDEWEB)

    Robin, M; Jastrzeb, M; Boisliveau, S; Boyer, R; Vidal, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1969-07-01

    This report describes a method for determining by {gamma} spectrometry the burn up and the specific power of fuel elements irradiated in power reactors. The energy spectrum of {gamma} rays emitted by fission products is measured by means of a simple equipment using a sodium iodide detector and a multichannel analyzer. In order to extract from the spectrum a quantity proportional to the burn up, it is necessary to: - isolate an activity specific of one emitter,- give the same importance to fissions in uranium and plutonium - take into account the radioactive decay during and after irradiation. One hundred fuel elements were studied and burn up values obtained by {gamma} spectrometry are compared to results given by chemical analyses. Preliminary measurements show that the accuracy of the results is greatly increased by the use of a germanium detector, due to its good resolution. (authors) [French] Ce rapport expose une methode de determination par spectrometrie {gamma} du taux d'irradiation et de la puissance specifique des elements combustibles irradies dans les reacteurs de puissance. Une installation simple utilisant un detecteur d'iodure de sodium et un selecteur multicanaux mesure le spectre en energie du rayonnement {gamma} emis par les produits de fission. Afin d'extraire du spectre une quantite proportionnelle au taux de combustion, il faut: - isoler une activite specifique a un emetteur, - donner la meme importance aux fissions survenues dans l'uranium et le plutonium, - prendre en compte la decroissance radioactive pendant et apres l'irradiation. Les mesures ont porte sur une centaine d'elements combustibles et les taux de combustion obtenus par spectrometrie {gamma} sont compares aux resultats des analyses chimiques. Des mesures preliminaires montrent que l'utilisation d'un detecteur de germanium augmente considerablement la precision des resultats, en raison de son excellente resolution. (auteurs)

  6. The Utilization of Background Spectrum to Calibrate Gamma Spectrometry

    International Nuclear Information System (INIS)

    Mahrouka, M. M.; Mutawa, A. M.

    2004-01-01

    Many developed countries have very poor reference standards to calibrate their nuclear instrumentations or may find some difficulties to obtain a reference standard. In this work a simple way for Gamma spectrometry calibration was developed. The method depends on one reference point and additional points from the background. The two derived equations were applied to the analyses of radioactive nuclides in soil and liquid samples prepared by IAEA laboratories through AL MERA Project. The results showed the precision of the methodology used, as well as, the possibility of using some points in the background spectrum as a replacement for reference standards of Gamma spectrometry calibration. (authors)

  7. Portable gamma spectrometry: measuring soil erosion in-situ at four Critical Zone Observatories in P. R. China

    Science.gov (United States)

    Sanderson, N. K.; Green, S. M.; Chen, Z.; Wang, J.; Wang, Y.; Wang, R.; Yu, K.; Tu, C.; Jia, X.; Li, G.; Peng, X.; Quine, T. A.

    2017-12-01

    Detecting patterns of soil erosion, redistribution, and/soil nutrient loss is important for long-term soil conservation and agricultural sustainability. Caesium-137 (137Cs) and other fallout radionuclide inventories have been used over the the last 50 years to track soil erosion, transport and deposition on a catchment scale, and have been shown to be useful for informing models of temporal/spatial soil redistribution. Traditional sampling methods usually involves coring, grinding, sieving, sub-sampling and laboratory analysis using HPGe detectors, all of which can be costly and time consuming. In-situ measurements can provide a mechanism for assessment of 137Cs over larger areas that integrate the spatial variability, and expand turnover of analyses. Here, we assess the applicability of an in-situ approach based on radionuclide principles, and provide a comparison of the two approaches: laboratory vs. in-situ. The UK-China Critical Zone Observatory (CZO) programme provides an ideal research platform to assess the in-situ approach to measuring soil erosion: using a portable gamma spectrometer to determine 137Cs inventories. Four extensive field slope surveys were conducted in the CZO's, which covers four ecosystem types in China: karst, red soil, peri-urban, and loess plateau. In each CZO, 3-6 plots were measured along 2 slope transects, with 3 replicated 1 hour counts of 137Cs in each plot. In addition, 137Cs soil depth and bulk density profiles were also sampled for each plot, and lab-derived inventories calculated using traditional methods for comparison. Accurately and rapidly measuring 137Cs inventories using a portable field detector allows for a greater coverage of sampling locations and the potential for small-scale spatial integration, as well as the ability to re-visit sites over time and continually adapt and improve soil erosion/redistribution models, thus more effectively targeting areas of interest with reduced cost and time constraints.

  8. The application of gamma-spectrometry to nuclear power plant (NPP) and environment

    International Nuclear Information System (INIS)

    Asgharizadeh, Farid.

    1995-01-01

    One of measuring systems is nuclear spectrometry, particularly Gamma-Ray Spectrometry, to measure and determine the radionuclide concentration within plant materials and environmental samples. There are four major applied techniques related to Nuclear Power Plant operation and environmental monitoring aspects. Some details about gamma ray spectrometry technique is discussed in chapter 2. The main emphasis is on the calculation of gamma-ray detector efficiency for different geometries, the minimum detectable activity concepts and dead-time correction. Also,some formula and relations are introduced. In chapter 3, the major applications of gamma-ray spectrometry for analysis of nuclear power plant and environmental samples are discussed. These applications are divided into four topics: Nuclear Fuel survey; based on the activity of fission products concentration in reactor coolant, two other applications are introduced: Fuel Burnup calculation and the calculation of rated activity of natural radionuclides in construction of materials which is the last and most important application: Measurement and determination of radionuclides activity concentr[[[[n in environmental samples is described through section 3.3 Sampling and measuring methods for research and monitoring aspects is evaluated. Some data about sample preparation methods such as pretreatment and solubilization procedures are presented. Quantitative chemical separations of trace constituents from complex sample materials invariably require meticulous work by an analytical chemist. The radiochemical separation deals with this subject. Instrumental aspects, relate to gamma-ray spectrometry, quality assurance, presentation and reporting of results are described. In the experimental part, determination of radionuclides concentration in sediment sample is presented

  9. Performance of gamma spectrometry counting system

    International Nuclear Information System (INIS)

    Yii Mei Wo; Maziah Mahmud

    2007-01-01

    Gamma spectrometry counting system widely used as tool to measure qualitative and quantitative gamma-ray emitters in a sample. Container size, sample to detector distance, sample volume are well known factors that affecting the quality of measurement. However, factor such as the age of the system was not been reported. Therefore, the objective of this study is to find out how the age factor affecting the quality of the measurement. From this study, it is found that when the age of the system increased, the system tends to have higher lower limit of detection and poorer linearity showing that age factor do affecting the quality of measurement. (Author)

  10. Assessment of measurement result uncertainty in determination of 210Pb with the focus on matrix composition effect in gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Iurian, A.R.; Pitois, A.; Kis-Benedek, G.; Migliori, A.; Padilla-Alvarez, R.; Ceccatelli, A.

    2016-01-01

    Reference materials were used to assess measurement result uncertainty in determination of 210 Pb by gamma-ray spectrometry, liquid scintillation counting, or indirectly by alpha-particle spectrometry, using its daughter 210 Po in radioactive equilibrium. Combined standard uncertainties of 210 Pb massic activities obtained by liquid scintillation counting are in the range 2–12%, depending on matrices and massic activity values. They are in the range 1–3% for the measurement of its daughter 210 Po using alpha-particle spectrometry. Three approaches (direct computation of counting efficiency and efficiency transfer approaches based on the computation and, respectively, experimental determination of the efficiency transfer factors) were applied for the evaluation of 210 Pb using gamma-ray spectrometry. Combined standard uncertainties of gamma-ray spectrometry results were found in the range 2–17%. The effect of matrix composition on self-attenuation was investigated and a detailed assessment of uncertainty components was performed. - Highlights: • Confirmed 210 Pb certified values by LSC and alpha-particle spectrometry ( 210 Po). • Assessed 210 Po measurement result uncertainty by alpha-particle spectrometry. • Matrix composition effect on gamma-ray spectrometry measurement result uncertainty. • Assessment of 210 Pb measurement result uncertainty by gamma-ray spectrometry. • Comparison of techniques and approaches: ‘fit-for-purpose’ considerations.

  11. In-pile gamma spectrometry and irradiation control at Osiris

    International Nuclear Information System (INIS)

    Farny, G.; Destot, M.; Corre, J.; Texier, D.; Faugere, J.L.; Mouchnino, M.

    1975-01-01

    A new gamma spectrometry facility is available near Osiris reactor core, at Saclay. This device enables nuclear fuels to be examined in loops or capsules all along their irradiation, a few minutes being sufficient to transfer the fuel from the irradiation place to the measurement bench. So, spacelike and timelike history of a lot of fission products, especially short-lived radionuclides, can be observed. Using such in-pile spectrometry device, of original design, allows to avoid radioactive decay corrections and the risks of any information less. Performance of the device is given together with some preliminary results and their interpretation [fr

  12. Methods for the analysis of the overlapped peaks in analytical gamma-spectrometry

    International Nuclear Information System (INIS)

    Sterlinski, S.; Wasek, M.

    1989-01-01

    A new simple method for the quantitative analysis of the doublet peaks in Ge(Li) or HPGe gamma-spectrometry is presented. No assumptions on the shape of the peaks in gamma-ray spectra being measured are required. Special feature of the method proposed is its usefulness for the analysis of closed doublets. 7 refs., 6 figs. (author)

  13. Optimization of measure parameters for an X- and gamma-ray spectrometry portable system

    International Nuclear Information System (INIS)

    Fernandes, Jaquiel S.; Appoloni, Carlos R.

    2008-01-01

    In order to optimize the use of a system for in situ gamma (γ)- and X-ray spectrometry composed of a 3x3x1 mm 3 Cadmium Telluride (CdTe) detector with respect to the detection of low-activity radioactive sources, a two level factorial planning was accomplished, involving three factors that could modify the system response. This planning was made with a 137 Cs punctual source, analyzing the X-ray energy line of 32 keV from 137m Ba. It was concluded that, for the system optimization, the best configuration for the involved parameters was to work with the detector at temperature of -22 o C, shaping time of 3 μs and rise time discrimination (RTD) with value 3

  14. Gammastic: towards a pseudo-gamma spectrometry in plastic scintillators

    International Nuclear Information System (INIS)

    Hamel, Matthieu; Dehe-Pittance, Chrystele; Coulon, Romain; Carrel, Frederick; Pillot, Philippe; Barat, Eric; Dautremer, Thomas; Montagu, Thierry; Normand, Stephane

    2013-06-01

    War against CBRN-E threats needs to continuously develop sensors with improved detection efficiency. More particularly, this topic concerns the NR controls for homeland security. A first analysis requires indeed a fast gamma spectrometry so as to detect potential special nuclear materials (SNM). To this aim, plastic scintillators could represent the best alternative for the production of large-scale, low-cost radiation portal monitors to be deployed on boarders, tolls, etc. Although they are known to be highly sensitive to gamma rays, due to their poor resolution, information relative to the nature of the SNM is tricky. Thus, only the Compton edge is obtained after interaction, and no information of the photoelectric peak is observed. This project concerns new developments on a possible pseudo-gamma spectrometry performed with plastic scintillators. This project is articulated on a combination of two developments: - The design of new materials most suitable for recovering the photoelectric peak after gamma interaction with the scintillator. This work concerns mainly plastic scintillators loading with heavy elements, such as lead or bismuth. - The analysis of the resulting signal with smart algorithms. This work is thus a pluri-disciplinary work performed at CEA LIST and embeds 4 main disciplines: MCNPX simulations (simulated spectra), chemistry of materials (preparation of various plastic scintillators with different properties), instrumentation (lab experiments) and smart algorithms. Really impressive results were obtained with the unfolding of simulated spectra at various energies (from 241 Am to 60 Co) and an innovative approach was proposed to counter-balance the quenching effect of luminescence by heavy elements in plastic scintillators. (authors)

  15. In situ lake pollutant survey using prompt-gamma probe

    International Nuclear Information System (INIS)

    Jiunnhsing Chao; Chien Chung

    1991-01-01

    An aluminium-made neutron-gamma probe, consisting of a 1.5 μg 252 Cf neutron source and a high purity germanium detector, was mounted on a mobile floating platform to survey chlorine pollutant concentration in lake water in situ. Laboratory tests for determining the probe operating depth and in situ field trials of a polluted lake were conducted; evaluation of radiation exposure to workers on board was carried out. The polluted chlorine concentration in lake water was found to be 86 ppm, with minimal radiation exposure for the operating crew on board. (author)

  16. Further development of IDGS: Isotope dilution gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Li, T.K.; Parker, J.L.; Kuno, Y.; Sato, S.; Kamata, M.; Akiyama, T.

    1991-01-01

    The isotope dilution gamma-ray spectrometry (IDGS) technique for determining the plutonium concentration and isotopic composition of highly radioactive spent-fuel dissolver solutions has been further developed. Both the sample preparation and the analysis have been improved. The plutonium isotopic analysis is based on high-resolution, low-energy gamma-ray spectrometry. The plutonium concentration in the dissolver solutions then is calculated from the measured isotopic differences among the spike, the dissolver solution, and the spiked dissolver solution. Plutonium concentrations and isotopic compositions of dissolver solutions analyzed from this study agree well with those obtained by traditional isotope dilution mass spectrometry (IDMS) and are consistent with the first IDGS experimental result. With the current detector efficiency, sample size, and a 100-min count time, the estimated precision is ∼0.5% for 239 Pu and 240 Pu isotopic analyses and ∼1% for the plutonium concentration analysis. 5 refs., 2 figs., 7 tabs

  17. In situ measurement of some gamma-emitting radionuclides in plant communities of the South Carolina coastal plain

    International Nuclear Information System (INIS)

    Ragsdale, H.L.; Tanner, B.K.; Coleman, R.N.; Palms, J.M.; Wood, R.E.

    1978-01-01

    In situ and laboratory gamma-ray spectroscopy measurements were taken in nine scrub oak forests and nine old fields to determine the applicability of in situ analysis in the coastal plain. Data collected at each of the 18 sites included a 2-hr count, soil density and moisture estimates, and vegetation measurements. Samples returned to the laboratory for radiometric analysis included litter and herbaceous vegetation and soil cores. Analysis of the gamma-emitter detection frequencies, concentrations, and burdens showed good to excellent agreement between laboratory and in situ methods. Generally, forests were determined to be superior in situ sampling systems. Laboratory analysis of collected samples may be a superior technique for gamma emitters with low energies, low concentrations, or nonuniform distributions in the soil. Three potential uses of in situ Ge(Li) spectrometers were identified and discussed in terms of their limits and of the replicate ecosystems appropriate for in situ analyses. Although the variety and the biogeochemical cycling regimes of southeastern coastal plain ecosystems complicate in situ analyses, it was concluded that comparable and probably accurate results can be achieved using in situ technology

  18. Methodology for determination of activity of radionuclides by gamma spectrometry

    International Nuclear Information System (INIS)

    Fragoso, Maria da Conceicao de Farias; Oliveira, Victor Rogerio S. de; Oliveira, Mercia L.; Lima, Fernando Roberto de Andrade

    2014-01-01

    Due to the growth in the number of procedures that make use of the positron emission tomography (PET), there is a need for standard solutions for the calibration of the systems used for the measurement of the PET radiopharmaceutical (activimeter) in radiopharmacies and in nuclear medicine services. Among the existing alternatives for the standardization of radioactive sources, the method known as gamma spectrometry is widely used for short-lived radionuclides. The purpose of this study was to implement the methodology for standardization of the 18 F solutions by gamma spectrometry at the Regional Center for Nuclear Sciences of the Northeast (CRCN-NE/CNEN-NE), Brazil. (author)

  19. Determination of uranium and thorium using gamma spectrometry: a pilot study

    Science.gov (United States)

    Olivares, D. M. M.; Koch, E. S.; Guevara, M. V. M.; Velasco, F. G.

    2018-03-01

    This paper presents the results of a pilot experiment aimed at standardizing procedures for the CPqCTR/UESC Gamma Spectrometry Laboratory (LEG) for the quantification of natural radioactive elements in solid environmental samples. The concentrations of 238U, 232Th and 40K in two sediment matrix belonging to the Caetité region were determined, by using the absolute method with uncertainties about 5%. The results were obtained using gamma spectrometry with a high-resolution p-type HPGe detector. As a closure, the absorbed dose, radium equivalent activity and the annual effective dose were calculated.

  20. Dose response of alanine and methyl alanine towards gamma and in-situ alpha irradiation

    International Nuclear Information System (INIS)

    Mohapatra, M.; Rajeswari, B.; Bhide, M.K.; Rane, Vinayak; Kadam, R.M.

    2017-01-01

    In situ alpha and external gamma dose response of two ESR (electron spin resonance) dosimetric materials namely alanine and methyl alanine were investigated. It was observed that alanine dosimeter had a better dose response in comparison to methyl alanine for the in-situ alpha irradiation by using 239 Pu powder. On the other hand, in case of gamma radiation, methyl alanine was found to have the sensitivity as twice that of alanine. (author)

  1. Gamma ray spectrometry results from core samples collected for RESUME 95

    Energy Technology Data Exchange (ETDEWEB)

    Sanderson, D.C.W.; Allyson, J.D. [SURRC, East Kilbride, Scotland (United Kingdom); Toivonen, H.; Honkamaa, T. [STUK, Helsinki (Finland)

    1997-12-31

    Field sampling of an airfield at Vesivehmaa, near Vaeaeksy, Finland (Area I) was carried out between 26-29 May 1995, to establish the radionuclide deposition and inventory of Chernobyl derived {sup 137}Cs, and natural radionuclides. The objective was to establish a common calibration site for in-situ and airborne gamma spectrometers, for Exercise RESUME 95 conducted in August 1995. The report presents the sampling details, handling and treatment. The analyses are discussed with particular emphasis given to {sup 137}Ca, {sup 134}Cs, {sup 40}K, {sup 214}Bi and {sup 208} radionuclides, and the quantification of their respective deposition and inventories. The results have been used to estimate the effective concentrations of nuclides at the calibration site for in-situ and airborne gamma spectrometry, and the depth distribution. For {sup 137}Cs the weighted mean activity per unit area takes on values of 50.7{+-}5.2 kBq m{sup -2} at 1 m ground clearance, 51.1{+-}6.9 kBq m{sup -2} at 50 m height and 47.9{+-}8.5 kBq m{sup -2} at 100 m. The similarity of these values confirms the suitability of the Vesivehmaa site for comparison of in-situ and airborne results despite variations of a factor of two between results from individual cores. The mean {alpha}/{rho} value for {sup 137}Cs in Area I is 0.77{+-}0.10 cm{sup 2}g{sup -1} (relaxation mass per unit area, {beta} 1.31{+-}0.15 gcm{sup -2}). Additional soil sampling across parts of Area II (a 6x3 km area selected for mapping Chernobyl deposition) was carried out. The mean level of {sup 137}Cs activity from these samples was 92.4{+-}63 kBq m{sup -2}, a sample taken near Laihansuo showing the largest value obtained at 172 kBq m{sup -2}. (EG). 17 refs.

  2. Gamma ray spectrometry results from core samples collected for RESUME 95

    Energy Technology Data Exchange (ETDEWEB)

    Sanderson, D C.W.; Allyson, J D [SURRC, East Kilbride, Scotland (United Kingdom); Toivonen, H; Honkamaa, T [STUK, Helsinki (Finland)

    1998-12-31

    Field sampling of an airfield at Vesivehmaa, near Vaeaeksy, Finland (Area I) was carried out between 26-29 May 1995, to establish the radionuclide deposition and inventory of Chernobyl derived {sup 137}Cs, and natural radionuclides. The objective was to establish a common calibration site for in-situ and airborne gamma spectrometers, for Exercise RESUME 95 conducted in August 1995. The report presents the sampling details, handling and treatment. The analyses are discussed with particular emphasis given to {sup 137}Ca, {sup 134}Cs, {sup 40}K, {sup 214}Bi and {sup 208} radionuclides, and the quantification of their respective deposition and inventories. The results have been used to estimate the effective concentrations of nuclides at the calibration site for in-situ and airborne gamma spectrometry, and the depth distribution. For {sup 137}Cs the weighted mean activity per unit area takes on values of 50.7{+-}5.2 kBq m{sup -2} at 1 m ground clearance, 51.1{+-}6.9 kBq m{sup -2} at 50 m height and 47.9{+-}8.5 kBq m{sup -2} at 100 m. The similarity of these values confirms the suitability of the Vesivehmaa site for comparison of in-situ and airborne results despite variations of a factor of two between results from individual cores. The mean {alpha}/{rho} value for {sup 137}Cs in Area I is 0.77{+-}0.10 cm{sup 2}g{sup -1} (relaxation mass per unit area, {beta} 1.31{+-}0.15 gcm{sup -2}). Additional soil sampling across parts of Area II (a 6x3 km area selected for mapping Chernobyl deposition) was carried out. The mean level of {sup 137}Cs activity from these samples was 92.4{+-}63 kBq m{sup -2}, a sample taken near Laihansuo showing the largest value obtained at 172 kBq m{sup -2}. (EG). 17 refs.

  3. Measuring the radium quartet (228Ra, 226Ra, 224Ra, 223Ra) in seawater samples using gamma spectrometry

    International Nuclear Information System (INIS)

    Beek, P. van; Souhaut, M.; Reyss, J.-L.

    2010-01-01

    Radium isotopes are widely used in marine studies (eg. to trace water masses, to quantify mixing processes or to study submarine groundwater discharge). While 228 Ra and 226 Ra are usually measured using gamma spectrometry, short-lived Ra isotopes ( 224 Ra and 223 Ra) are usually measured using a Radium Delayed Coincidence Counter (RaDeCC). Here we show that the four radium isotopes can be analyzed using gamma spectrometry. We report 226 Ra, 228 Ra, 224 Ra, 223 Ra activities measured using low-background gamma spectrometry in standard samples, in water samples collected in the vicinity of our laboratory (La Palme and Vaccares lagoons, France) but also in seawater samples collected in the plume of the Amazon river, off French Guyana (AMANDES project). The 223 Ra and 224 Ra activities determined in these samples using gamma spectrometry were compared to the activities determined using RaDeCC. Activities determined using the two techniques are in good agreement. Uncertainties associated with the 224 Ra activities are similar for the two techniques. RaDeCC is more sensitive for the detection of low 223 Ra activities. Gamma spectrometry thus constitutes an alternate method for the determination of short-lived Ra isotopes.

  4. Demonstrating the European capability for airborne gamma spectrometry: results from the eccomags exercise

    International Nuclear Information System (INIS)

    Sanderson, D.C.W.

    2003-01-01

    Full text: Airborne gamma spectrometry has emerged over recent years as an important means for mapping deposited activity and dose-rates in the environment. Its importance to emergency response has been increasingly recognised in defining contaminated areas at rates of measurement and spatial density which simply cannot be matched using ground based methods. In Europe the practical capability for AGS has developed markedly over the period since the Chernobyl accident, and significant progress towards cooperation between AGS teams, and convergence of methodology has been made, largely as the result of work conducted with support from the Commission under Frameworks IV and V. As an important part of the ECCOMAGS project an international comparison was undertaken in SW Scotland in 2002 to evaluate the performance of AGS teams in comparison with established groundbased methods. The work included a composite mapping task whereby different AGS teams recorded data over adjacent areas, to demonstrate the potential for collective actions in emergency response. More than 70,000 observations were made from a 90x40 km area during a 3 day period by several European teams, and compiled within days to produce regional scale maps for 137-Cs contamination and environmental gamma dose-rates. In three disjoint common areas AGS and ground based observations were taken. The ground based work was split for practical reasons into two phases; a pre-characterization stage to define calibration sites, and a second stage where sampling of additional sites was undertake synchronously with the exercise to provide the basis for blind intercomparison with AGS. More than 800 laboratory gamma spectrometry measurements were taken in support of this activity, which in combination with in-situ gamma spectrometry and instrumental dose-rate measurements were used to define the ground-based estimates of 137-Cs activity per unit area and dose-rate. AGS for the common areas, included points for ground

  5. Decreasing of the detection limit for gamma-ray Spectrometry with the influence of sample treatment

    International Nuclear Information System (INIS)

    Karami, M.; Sadighzadeh, A.; Asgharizadeh, F.; Sardari, D.; Tavassoli, A.; Arbabi, A.; Hochaghani, O.

    2009-01-01

    Full text: In this study the ash method has been applied for environmental sample treatment in order to decrease of the detection limit in gamma-ray spectrometry for low level radioactivity measurements. Detection limit in gamma ray spectrometry is the smallest expectation value of the net counting rate that can be detected on given probabilities. The environmental test samples have been changed into ash using a suitable oven. The heating were made under controlled temperature to avoid the escape of some radionuclides such as radiocaesium. The ash samples were measured by high resolution gamma-ray spectrometry system. (author)

  6. PEAKS: Computer code for solving partly overlapped photopeak in gamma spectrometry

    International Nuclear Information System (INIS)

    Jerez Vergueria, Sergio; Jerez Vergueria, Pablo

    1996-01-01

    The paper describes the main elements of the code according to purposes and contents. The PEAKS code is a useful tool of comfortable and easy handling for solving, partly overlapped photopeak in gamma spectrometry with NaI(Ti) detector

  7. The first results of measurements in military hospital laboratory for gamma spectrometry analysis

    International Nuclear Information System (INIS)

    Jankovic, Lj.; Pantelic, G.; Misovic, M.

    1997-01-01

    In this paper we present the basic features of the equipment for gamma spectrometry analysis and the first measurements results of the 134 Cs and 137 Cs activities. Gamma spectrum is measured using HP GE Detector. The obtained results show low level activities of the 134 Cs and 137 Cs in the environment. (author)

  8. In situ analysis of coal by scintillation gamma-ray spectrometry in deep boreholes

    International Nuclear Information System (INIS)

    Chrusciel, E.; Kopec, M.; Niewodniczanski, J.; Palka, K.W.; Kaczmarski, S.M.; Wojda, F.

    1987-01-01

    Neutron-gamma and gamma-gamma spectrometric loggings have been used for evaluation of coal seams. Interpretation of the logging curves was based on the method of spectrometric parameters i.e. the ratios of gamma-ray intensities recorded within two energy intervals, which depended strongly on a given parameter of coal, while the influence of other parameters is reduced. The boundaries of energy intervals were chosen by multiple correlation analysis of the results of point measurements and results of coal samples assessments. These energy intervals are later used in continuous borehole logging. Some of the coal parameters can be determined by both logging methods, other by one method only. The logging tools are described and examples of the determination of carbon, sulphur, iron, calcium, ash content, calorific value, density and moisture of coal are given. The agreement with the results of laboratory analyses seems quite satisfactory, especially when the calibration procedure was made for the same part of a coal basin. 13 refs., 6 figs., 5 tabs. (author)

  9. Gamma spectrometry analysis of fertilizers used in Costa Rica

    International Nuclear Information System (INIS)

    Loria, L.G.; Jimenez, R.; Badilla, M.

    2002-01-01

    Using the low level gamma spectrometry technique, the specific activity of natural and artificial isotopes present in national consumption fertilizers, supplied by local dealers, was quantified. The most outstanding isotope found in some of the fertilizers is U 235 , with an specific activity higher than the expected in this kind of product, which might mean that this isotope comes from imported raw material. (Author) [es

  10. Determination of uranium and thorium using gamma spectrometry: A pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Olivares, D.M.M.; Koch, E.S.; Manso Guevara, M.V.; Garcia Velasco, F., E-mail: diango.mo87@gmail.com [Universidade Estadual de Santa Cruz (UNESC), Ilhéus, BA (Brazil)

    2017-07-01

    This paper presents the results of a pilot experiment aimed at standardizing procedures for the CPqCTR/UESC Gamma Spectrometry Laboratory (LEG) for the quantification of natural radioactive elements in solid environmental samples. The concentrations of {sup 238}U, {sup 232}Th and {sup 40}K in two sediment matrix belonging to the Caetité region were determined, by using the absolute method with uncertainties about 5%. The results were obtained using gamma spectrometry with a high-resolution p-type HPGe detector. As a closure, the absorbed dose, radium equivalent activity and the annual effective dose were calculated. (author)

  11. Computer programs for data reduction and interpretation in plutonium and uranium analysis by gamma ray spectrometry

    International Nuclear Information System (INIS)

    Singh, R.K.; Moorthy, A.D.; Babbar, R.K.; Udagatti, S.V.

    1989-01-01

    Non destructive gamma ray have been developed for analysis of isotopic abundances and concentrations of plutonium and uranium in the respective product solutions of a reprocessing plant. The method involves analysis of gamma rays emitted from the sample and uses a multichannel analyser system. Data reduction and interpretation of these techniques are tedious and time consuming. In order to make it possible to use them in routine analysis, computer programs have been developed in HP-BASIC language which can be used in HP-9845B desktop computer. A set of programs, for plutonium estimation by high resolution gamma ray spectrometry and for on-line measurement of uranium by gamma ray spectrometry are described in this report. (author) 4 refs., 3 tabs., 6 figs

  12. Area specific stripping of lower energy windows for AGS and CGS NaI systems[Airborne Gamma Spectrometry; Carbone Gamma Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Korsbech, U.; Aage, H.K. [Technical Univ. of Denmark (Denmark); Bystroem, S.; Wedmark, M. [Geological Survey of Sweden (Sweden); Thorshaug, S. [Norwegian Radiation Protection Agency (Norway); Bargholz, K. [Danish Emergency Management Agency (Denmark)

    2005-05-01

    The report describes the results from a NKS (Nordic Nuclear Safety Research) project aiming at examining the possibilities for extracting stripping factors for Airborne Gamma-ray Spectrometry (AGS) data and Carborne Gamma-ray Spectrometry (CGS) data directly from the recorded set of data, i.e. without having to calibrate the detector systems on beforehand. The project 'NKS project ASSb' has been carried out between 1 August 2004 and 31 March 2005 by a research group composed of persons from Technical University of Denmark (DTU), Danish Emergency Management Agency (DEMA), Geological Survey of Sweden (SGU), and Norwegian Radiation Protection Authority (NRPA). The AGS and CGS data sets used for the project were recorded by SGU, DEMA, NGU (Geological Survey of Norway), and SSI (Swedish Radiation Protection Institute). Most of the project effort has been directed towards analysing AGS and CGS data with point source signals recorded at the Barents Rescue 2001 LIVEX exercise at Boden in Sweden. Possibilities and limitations for the method have been identified. (au)

  13. Time sequence determination of parent–daughter radionuclides using gamma-spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Burnett, J. L.; Britton, R. E.; Abrecht, D. G.; Davies, A. V.

    2017-05-06

    The acquisition of time-stamped list (TLIST) data provides additional information useful to gamma-spectrometry analysis. A novel technique is described that uses non-linear least-squares fitting and the Levenberg-Marquardt algorithm to simultaneously determine parent-daughter atoms from time sequence measurements of only the daughter radionuclide. This has been demonstrated for the radioactive decay of short-lived radon progeny (214Pb/214Bi, 212Pb/212Bi) described using the Bateman first-order differential equation. The calculated atoms are in excellent agreement with measured atoms, with a difference of 1.3 – 4.8% for parent atoms and 2.4% - 10.4% for daughter atoms. Measurements are also reported with reduced uncertainty. The technique has potential to redefine gamma-spectrometry analysis.

  14. Development of source-less efficiency calibration procedure for CeBr3 based gamma spectrometry system

    International Nuclear Information System (INIS)

    Verma, Amit K.; Narayani, K.; Pant, Amar D.; Bhosale, Nitin; Anilkumar, S.; Palani Selvam, T.

    2018-01-01

    Scintillation spectrometers are widely used in detection and spectrometry of gamma photons. Sodium Iodide (NaI(Tl)) is the most commonly used scintillation detector for gamma ray spectrometry. However for portable application that require higher efficiency and better resolution Cerium Bromide (CeBr 3 ) crystals are more suitable than NaI(Tl) crystals. CeBr 3 detectors have high light output (∼ 68,000 photons/MeV), good proportionality, fast response and better energy resolution (<4% for 662 keV of 137 Cs), which makes it very promising detector for gamma ray spectrometry. In the present work, experimental and Monte Carlo based efficiencies for CeBr 3 detector for 137 Cs and 60 Co were evaluated

  15. A gamma-spectrometer determining equilibrium factor in situ

    International Nuclear Information System (INIS)

    Feng Weiheng

    1992-01-01

    The author expounds main function, scientific value and practical significance of Model SY500 gamma-spectrometer, which can determine radioactive factor equilibrium (k p ) in-situ. Accuracy, steadiness and differential of the technology has been proved on the models of Radiometric Measurement Station of China Nuclear Industry Corporation. The author enumerates several examples such as k p survey at gold-bearing glebe, at uranium-bearing glebe, at the ground above ground water and 21 stations of Beijing subway

  16. Determination of uranium-235 by differential gamma spectrometry

    International Nuclear Information System (INIS)

    Suner, A.A.; La Gamma de Batistoni, A.M.G.; Botbol, J.

    1974-12-01

    A method for the determination of U-235 contained in solutions of uranium, by gamma spectrometry with Ge(Li) detector is described. Ra-226 is coprecipitated in BaSO 4 . The activity at 186 keV is measured, substracted by the corresponding of a standard. The detection limit is 1% of increment of U-235 over the standard. (author)

  17. Efficiency curves of NIRR-1 gamma-ray spectrometry system at near ...

    African Journals Online (AJOL)

    The full-energy peak efficiency curves of the gamma-ray spectrometry for use with the Nigeria Research Reactor-1 (NIRR-1) have been determined by both theoretical and experimental at two source-detector positions for routine neutron activation analysis. Standard gamma ray sources were used to determine the efficiency ...

  18. Optimization of in situ prompt gamma-ray analysis using a HPGe-252Cf probe

    International Nuclear Information System (INIS)

    Chien Chung; Jiunnhsing Chao

    1991-01-01

    Application of in situ measurements by the neutron-induced prompt gamma-ray activation analysis (PGAA) technique to geochemical analysis and mineral survey have been investigated. An in situ survey of water pollutants by PGAA techniques was first proposed in the authors' previous study, where a 2.7-μg 252 Cf neutron source used in connection with a gamma-ray detecting system to determine water pollutants was described. In this paper the authors describe a modified detection probe designed and constructed to look for the optimum conditions of various-intensity 252 Cf neutron sources in measurement of some elements in lake water. Detecting efficiencies at high-energy regions and detection limits for elements commonly found in polluted lakes were evaluated and predicted to investigate the potential application of the probe for in situ measurements

  19. Radiochemical separation of {sup 231}Pa from siliceous cake prior to its determination by gamma ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Dalvi, Aditi A. [Bhabha Atomic Research Centre, Mumbai (India). Analytical Chemistry Div.; Homi Bhabha National Institute, Mumbai (India); Verma, Rakesh

    2017-07-01

    A simple and fast radiochemical method for the separation of protactinium ({sup 231}Pa) from siliceous cake for its determination by gamma ray spectrometry is described. The method involves (a) a novel approach, the fusion of the siliceous cake with sodium peroxide, (b) the dissolution of the fused mass in nitric acid and (c) the co-precipitation of {sup 231}Pa with manganese dioxide formed in-situ by the addition of solid manganous sulfate and potassium permanganate to the solution. The fusion, effected in a single step, is simpler and highly effective in comparison to methods reported hitherto in literature. The radiochemical yield of {sup 231}Pa, determined using 311.9 keV gamma ray of {sup 233}Pa radiotracer is quantitative (∝90%). The decontamination factors calculated using gamma ray spectrometry and energy dispersive X-ray fluorescence measurements show that the separation from the interfering radionuclides is high whereas separation from major and minor elements is good. Separation by ion-exchange method in hydrochloric acid, hydrofluoric acid and oxalic acid media have comparatively much lower yields. The concentration of {sup 231}Pa in the siliceous cake measured using interference-free 283.6 keV gamma ray was found to be (6.4 ± 0.33) μg kg{sup -1}. The measured concentration of {sup 231}Pa was well above the limit of quantitation whereas the coefficient of variation was ∝5%. The improvement in the limit of detection was due to the reduction in spectral background. Systematic evaluation of various uncertainty parameters showed that the major contributors to the combined uncertainty were efficiency of the high purity germanium detector and the counting statistics. The present sample decomposition and separation methods are robust, simple to perform and can be effectively used for the determination and hence source prospecting of protactinium.

  20. Determination of the self-attenuation correction factor for environmental samples analysis in gamma spectrometry

    International Nuclear Information System (INIS)

    Santos, Talita O.; Rocha, Zildete; Knupp, Eliana A.N.; Kastner, Geraldo F.; Oliveira, Arno H. de; Oliveira, Arno H. de

    2015-01-01

    Gamma spectrometry technique has been used in order to obtain the activity concentrations of natural and artificial radionuclides in environmental samples of different origins, compositions and densities. These samples characteristics may influence the calibration condition by the self-attenuation effect. The sample density has been considered the most important factor. For reliable results, it is necessary to determine self-attenuation correction factor which has been subject of great interest due to its effect on activity concentration. In this context, the aim of this work is to show the calibration process considering the correction by self-attenuation in the evaluation of the concentration of each radionuclide to a gamma HPGEe detector spectrometry system. (author)

  1. Proceedings of the International Symposium Advances in alpha, Beta- and Gamma-Ray spectrometry

    International Nuclear Information System (INIS)

    1997-01-01

    The International Committee for Radionuclide Metrology (ICRM) is an association of radionuclide metrology laboratories whose membership is composed of delegates of these laboratories together with other scientists actively engaged in the study and applications of radioactivity. The scientific activities are carried out in the frame of six Working Groups. Two of them, the Alpha-Particle Spectrometry and the Gamma-and Beta-ray Spectrometry Working Groups held a common workshop in Pushkin, St. Petersburg, 18 to 20 September 1996, under the title Advances in Alpha-Beta-and Gamma-Ray Sepectrometry, at the kind invitation of the D.I. Mendeleyev Institute for Metrology. More than 30 people from 14 laboratories attended the meeting, and nineteen oral communications were presented, from which twelve were retained for publication an are included in these proceedings. (Author)

  2. In situ measurements of dose rates from terrestrial gamma rays

    International Nuclear Information System (INIS)

    Horng, M.C.; Jiang, S.H.

    2002-01-01

    A portable, high purity germanium (HPGe) detector was employed for the performance of in situ measurements of radionuclide activity concentrations in the ground in Taiwan, at altitudes ranging from sea level to 3900 m. The absolute peak efficiency of the HPGe detector for a gamma-ray source uniformly distributed in the semi-infinite ground was determined using a semi-empirical method. The gamma-ray dose rates from terrestrial radionuclides were calculated from the measured activity levels using recently published dose rate conversion factors. The absorbed dose rate in air due to cosmic rays was derived by subtracting the terrestrial gamma-ray dose rate from the overall absorbed dose rate in air measured using a high-pressure ionization chamber. The cosmic-ray dose rate calculated as a function of altitude, was found to be in good agreement with the data reported by UNSCEAR. (orig.)

  3. Laboratory of High resolution gamma spectrometry

    International Nuclear Information System (INIS)

    Mendez G, A.; Giber F, J.; Rivas C, I.; Reyes A, B.

    1992-01-01

    The Department of Nuclear Experimentation of the Nuclear Systems Management requests the collaboration of the Engineering unit for the supervision of the execution of the work of the High resolution Gamma spectrometry and low bottom laboratory, using the hut of the sub critic reactor of the Nuclear Center of Mexico. This laboratory has the purpose of determining the activity of special materials irradiated in nuclear power plants. In this report the architecture development, concepts, materials and diagrams for the realization of this type of work are presented. (Author)

  4. Factors influencing in situ gamma-ray measurements

    Science.gov (United States)

    Loonstra, E. H.; van Egmond, F. M.

    2009-04-01

    Introduction In situ passive gamma-ray sensors are very well suitable for mapping physical soil properties. In order to make a qualitative sound soil map, high quality input parameters for calibration are required. This paper will focus on the factors that affect the output of in situ passive gamma-ray sensors, the primary source, soil, not taken into account. Factors The gamma-ray spectrum contains information of naturally occurring nuclides 40K, 238U and 232Th and man-made nuclides like 137Cs, as well as the total count rate. Factors that influence the concentration of these nuclides and the count rate can be classified in 3 categories. These are sensor design, environmental conditions and operational circumstances. Sensor design The main elements of an in situ gamma-ray sensor that influence the outcome and quality of the output are the crystal and the spectrum analysis method. Material and size of the crystal determine the energy resolution. Though widely used, NaI crystals are not the most efficient capturer of gamma radiation. Alternatives are BGO and CsI. BGO has a low peak resolution, which prohibits use in cases where man-made nuclides are subject of interest. The material is expensive and prone to temperature instability. CsI is robust compared to NaI and BGO. The density of CsI is higher than NaI, yielding better efficiency, especially for smaller crystal sizes. More volume results in higher energy efficiency. The reduction of the measured spectral information into concentration of radionuclides is mostly done using the Windows analysis method. In Windows, the activities of the nuclides are found by summing the intensities of the spectrum found in a certain interval surrounding a peak. A major flaw of the Windows method is the limited amount of spectral information that is incorporated into the analysis. Another weakness is the inherent use of ‘stripping factors' to account for contributions of radiation from nuclide A into the peak of nuclide B. This

  5. Pulser injection with subsequent removal for gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Hartwell, J.K.; Goodwin, S.G.; Johnson, L.O.; Killian, E.W.

    1990-01-01

    This patent describes a module for use with a gamma-ray spectroscopy system. The system includes a gamma-ray detector for detecting gamma-ray events and producing a signal representing the gamma-ray events, a converter responsive to the detector and capable of converting the signal to a spectrum, a storage memory responsive to the converter and capable of storing the spectrum at address locations in memory, and a pulser capable of injecting pulses into the signal produced by the detector. The module comprises: means for generating a logic pulse for controlling the pulser, the controlling means adapted for coupling to the pulser; means for generating separation of events logic to isolate the components of a combined gamma-ray---pulse spectrum, the separation of events logic means adapted for coupling to the converter and the storage memory with the capability of storing pulses at address locations in the storage memory separate from the gamma-ray events; means for receiving an imitating signal from the converter to generate a plurality of operations by the module; means for tracking variations in a gamma-ray---pulse spectrum brought on by external parameter changes; and means for interfacing with commercially developed gamma-ray spectrometry equipment

  6. Calibration of HPGe detector for in situ measurements of 137Cs in soil by 'peak to valley' method

    International Nuclear Information System (INIS)

    Fueloep, M.

    2000-01-01

    The contamination of soil with gamma-ray emitters can be measured in two ways: soil sampling method and in situ spectrometry of the ambient gamma-ray radiation. The conventional soil sampling method has two disadvantages: samples may not be representative for a large areas and determination of the depth distribution of radionuclide requires the measurement of several samples taken from different depths. In situ measurement of a radionuclide activity in soil is more sensitive and provides more representative data than data obtained by soil sample collection and subsequent laboratory analysis. In emergency situations time to assess the contamination is critical. For rapid assessment of the deposited activity direct measurement of ambient gamma-ray radiation are used. In order to obtain accurate measurements of radionuclides in the soil, the detector should be placed on relatively even and open terrain. It is our customary practice to place the detector 1 m above the soil surface. At this height, a tripod-mounted detector can be handled easily and still provide a radius of view for gamma emitting sources out to about 10 m. The 'field of view' actually varies, being somewhat larger for higher sources. Depending upon source energy, the detector effectively sees down to a depth of 15-30 cm. Commonly used method for field gamma spectrometry is method by Beck (1). The most important disadvantages of in situ spectrometry by Beck are that the accuracy of the analysis depends on a separate knowledge of the radioactivity distribution with soil depth. This information can be obtained by calculations using data from in situ measurements and energy dependence of absorption and scattering of photons in soil and track length distribution of photons in soil (2). A method of in situ measurements of 137 Cs in soil where radionuclide distribution in soil profile is calculated by unfolding of detector responses in the full energy peak net area at 0.662 MeV and in the valley under the

  7. New possibilities in prompt gamma ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Borderie, B; Barrandon, J N [Centre National de la Recherche Scientifique, 45 - Orleans-la-Source (France). Lab. du cyclotron; Pinault, J L [Bureau de Recherches Geologiques et Minieres (BRGM), 45 - Orleans (France)

    1977-01-01

    Prompt gamma ray spectrometry has been used as an analytical tool for many years. The high level of background noise does, however, remain a major problem with this technique. From simple theoretical consideration, conditions (particle, energy) were determined to reduce significantly the background noise under irradiation. Alpha particles of 3.5 MeV were chosen. Some fifty elements were studied, of which 24 gave interesting results. The detection limits obtained for a sample of niobium were as follows: approximately 1 ppm (10/sup -6/g/g) for the light elements Li, B, F and Na, and between 50 ppm and 1% for the others. Numerous applications may be envisaged in the geo- and cosmo-sciences.

  8. Use of a Shielded High Resolution Gamma Spectrometry System to Segregate LLW from Contact Handleable ILW Containing Plutonium - 13046

    Energy Technology Data Exchange (ETDEWEB)

    Lester, Rosemary; Wilkins, Colin [Canberra UK Ltd, Unit 1 B528.1, Harwell Science Campus, Oxfordshire OX11 0DF (United Kingdom); Chard, Patrick [Canberra UK Ltd, Forss Business and Technology park, Thurso, Caithness KW14 7UZ (United Kingdom); Jaederstroem, Henrik; LeBlanc, Paul; Mowry, Rick [Canberra Industries, Inc., 800 Research Parkway, Meriden, Connecticut, 06450 (United States); MacDonald, Sanders; Gunn, William [Dounreay Site Restoration Limited, Dounreay, Thurso, Caithness, KW14 7TZ (United Kingdom)

    2013-07-01

    Dounreay Site Restoration Limited (DSRL) have a number of drums of solid waste that may contain Plutonium Contaminated Material. These are currently categorised as Contact Handleable Intermediate Level Waste (CHILW). A significant fraction of these drums potentially contain waste that is in the Low Level Waste (LLW) category. A Canberra Q2 shielded high resolution gamma spectrometry system is being used to quantify the total activity of drums that are potentially in the LLW category in order to segregate those that do contain LLW from CHILW drums and thus to minimise the total volume of waste in the higher category. Am-241 is being used as an indicator of the presence of plutonium in the waste from its strong 59.54 keV gamma-ray; a knowledge of the different waste streams from which the material originates allows a pessimistic waste 'fingerprint' to be used in order to determine an upper limit to the activities of the weak and non-gamma-emitting plutonium and associated radionuclides. This paper describes the main features of the high resolution gamma spectrometry system being used by DSRL to perform the segregation of CHILW and LLW and how it was configured and calibrated using the Canberra In-Situ Object Counting System (ISOCS). It also describes how potential LLW drums are selected for assay and how the system uses the existing waste stream fingerprint information to determine a reliable upper limit for the total activity present in each measured drum. Results from the initial on-site commissioning trials and the first measurements of waste drums using the new monitor are presented. (authors)

  9. Design and fabrication of shielding for gamma spectrometry

    International Nuclear Information System (INIS)

    Mariano H, E.

    1991-05-01

    To have a system of gamma spectrometry in the Radiological Mobile Unit No. 1 (UMOR-1) was designed and manufactured an armor-plating appropriate to this, to make analysis of radioactive samples in place in the event of a radiological emergency, besides being able to give support to the Management of Radiological Safety, and even to give service of sample analysis of other Institutions. (Author)

  10. Review of in situ derivatization techniques for enhanced bioanalysis using liquid chromatography with mass spectrometry.

    Science.gov (United States)

    Baghdady, Yehia Z; Schug, Kevin A

    2016-01-01

    Accurate and specific analysis of target molecules in complex biological matrices remains a significant challenge, especially when ultra-trace detection limits are required. Liquid chromatography with mass spectrometry is often the method of choice for bioanalysis. Conventional sample preparation and clean-up methods prior to the analysis of biological fluids such as liquid-liquid extraction, solid-phase extraction, or protein precipitation are time-consuming, tedious, and can negatively affect target recovery and detection sensitivity. An alternative or complementary strategy is the use of an off-line or on-line in situ derivatization technique. In situ derivatization can be incorporated to directly derivatize target analytes in their native biological matrices, without any prior sample clean-up methods, to substitute or even enhance the extraction and preconcentration efficiency of these traditional sample preparation methods. Designed appropriately, it can reduce the number of sample preparation steps necessary prior to analysis. Moreover, in situ derivatization can be used to enhance the performance of the developed liquid chromatography with mass spectrometry-based bioanalysis methods regarding stability, chromatographic separation, selectivity, and ionization efficiency. This review presents an overview of the commonly used in situ derivatization techniques coupled to liquid chromatography with mass spectrometry-based bioanalysis to guide and to stimulate future research. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Determination of 210Pb by direct gamma-ray spectrometry, beta counting via 210Bi and alpha-particle spectrometry via 210Po in coal, slag and ash samples from thermal power plant

    International Nuclear Information System (INIS)

    Seslak, Bojan; Vukanac, Ivana; Kandic, Aleksandar; Durasevic, Mirjana; Eric, Milic; Jevremovic, Aleksandar

    2017-01-01

    In order to compare three different techniques and estimate radiological impact, activity concentration of 210 Pb in coal, slag and ash samples from thermal power plant 'Nikola Tesla', Serbia, were measured, and results are presented in this study. Determination of 210 Pb was carried out in three ways: using HPGe gamma spectrometer and via in-growth of 210 Po and 210 Bi by alpha-particle spectrometry and proportional counting, respectively. The results obtained for three different techniques were compared. Statistical analysis and comparison of methods were carried out by combination of Z score and χ 2 statistical tests. Tests results, as well as values of measured activities concentrations obtained by alpha and gamma spectrometry, showed that gamma spectrometry is a valid alternative to time-consuming alpha spectrometry for low level activity measurements of 210 Pb. This remark is also valid even for gamma spectrometers with poor efficiency in low energy region. (author)

  12. Low level GAMMA0 spectrometry by beta-gamma coincidence

    International Nuclear Information System (INIS)

    Grigorescu, E.L.; Luca, A.; Razdolescu, A.C.; Ivan, C.

    1999-01-01

    Low level gamma spectrometry has a wide application, especially in environmental monitoring. Two variants, based on a beta-gamma coincidence technique, were studied. The equipment was composed of a beta detector and a Ge(Li) gamma detector (6% - relative efficiency), with the associated electronics. The gamma rays are recorded by the multichannel analyzer (4096 channels) only if the associated beta particles, which precede the gamma transitions, are registered in coincidence. Two types of beta detectors were used: plastic and liquid scintillators. In both cases, an external lead shield of 5 cm thick was used. The integral gamma background (50-1700 KeV) was reduced about 85 and 50 times, respectively. The corresponding MDA (Minimum Detectable Activity) values decreased about 1.5 and (3-7) times, respectively. The 2π sr plastic beta detector was placed on top the Ge(Li). The sample was inserted between the two detectors. The measurement time was 10 4 s. A 4π sr detector, built of the same material, was also studied, but it proved to be less advantageous because the background was reduced only 16 times; for a MDA reduction similar with that of the 2π sr variant, a longer measurement was needed (3.10 4 s). The other type of beta detector used, was a liquid scintillator. The dissolving of the samples in scintillator ensures a 4π sr measurement geometry. The vials with scintillator (10 ml volume) were placed on top the Ge(Li) and visualised by the photocathode of a phototube. This setup was surrounded by an enclosure which prevent the light penetration. The measurement time was 10 4 s. The only difficulty encountered in this low level measurement method is the accurate determination of the beta efficiency. A limitation is the possibility to measure only small mass samples. These variants are more simple and cheaper than others, previously studied. The advantage of the method is obvious when, instead of low MDA values, shorter measurement times are preferred. The

  13. Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966)

    International Nuclear Information System (INIS)

    Chesselet, R.

    1969-01-01

    The results described in this study are relative to the artificial radioactivity of such elements as zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 and praseodymium-144 which were present in the atmospheric fallout between 1962 and 1964, and their incidence in superficial marine waters. Various physical, chemical or biological processes are studied by a high sensitivity gamma ray spectrometry technic, using those radioelements as 'tracers'. The change of state in sea water of an important fraction (about 50 per cent) of the radioactive particles going into the soluble phase - this phenomenon was not expected for those radioelements - controls the processes of accumulation in the planktonic biomass and the diffusion towards deeper waters. On the other hand, an 'in situ' spectrometry method is described. It enables the direct measurement in the sea of very low concentrations of some gamma ray emitters. The application of this method has made possible to carry out numerous observations in the surface waters of the Western Mediterranean sea and in the Bay of Biscay. It is shown that the mixing depth is closely connected to the depth of the thermocline. An accumulation process at this level is observed. The diffusion coefficients are similar to the thermal turbulent coefficient. The existence during several months of 'compartments' is established for the surface waters of the Bay of Biscay. From the establishment of the budget of fall-out, a comparative study shows that the rate of radioactive fallout on the maritime zone considered is always two to three times higher than on the neighbouring continental regions. Several explanations of this phenomenon are discussed. (author) [fr

  14. The results obtained by INR-Pitesti to an international in-situ intercomparison exercise

    International Nuclear Information System (INIS)

    Dobrin, Relu; Dulama, Cristian; Toma, Alexandru

    2008-01-01

    Full text: The determination of soil contamination, dose rate measurements and in-situ gamma spectrometry are well established and widely used measurement procedures, especially after large scale nuclear incidents. To support decision makers and first responders with a more comprehensive and accurate overview immediately after a large scale nuclear or radiological emergency, as releases from a nuclear power plant or a terrorist attack with a dirty bomb, a fast and clear presentation of measurement data is indispensable. In 2007, the Austrian Research Centers GmbH - ARC (Seibersdorf) in cooperation with IAEA and the Austrian NBC Defense School organized an international measurement campaign, 'In-Situ Intercomparison Scenario' ISIS 2007, with the focus on In-Situ Gamma Spectrometry and Dose Rate Measurements in Emergency Situations. 56 teams from 25 countries, worldwide, took part to this exercise. The only Romanian team was 'CROWN'. The CROWN Laboratory is part of the Radiation Protection Laboratory of the Institute for Nuclear Research - Pitesti, certified for characterization of radioactive wastes and nuclear materials. The paper presents results obtained during different tasks of the exercise: 'Dose rate mapping'; 'Localization - Drive by'; 'Simulation of a contamination'; 'Identification Shielded; 'Identification/Quantification'; 'Buried sources; 'Environmental measurement'. (authors)

  15. Application of gamma ray spectrometry for evaluation of transfer factors in environmental matrices

    International Nuclear Information System (INIS)

    Rao, D.D.

    2008-01-01

    Gamma Ray Spectrometry (GRS) is performed using a variety of radiation detectors, to identify and determine radioactivity concentration of gamma emitting radionuclides qualitatively, in a wide range of samples. The samples can be of a high inventory power plant origin, NORM category or low level environmental samples, around a power plant. The method is usually applied to non-destructive analysis of environmental samples. However, it can also be applied to destructive analysis i.e. following extraction/separation of the analyte from the sample, if there is a need to pre-concentrate the analyte. The accuracy and precision of the method, depends on the quality of calibration, correction methods employed, stability of the system components, computational algorithms used, analysis of sources of uncertainties etc. The transfer factors among the environmental matrices are simple ratios, but the methodologies used in generating the respective concentrations have to be appropriately documented, including the validity of measurements. Validation mechanisms can include the results of international inter-comparison exercises, the certificates of standards issued by quality-accredited international laboratories. A few parameters involved in the qualitative analysis of gamma spectrometry are discussed here

  16. X-ray fluorescence and gamma-ray spectrometry combined with multivariate analysis for topographic studies in agricultural soil

    International Nuclear Information System (INIS)

    Castilhos, Natara D.B. de; Melquiades, Fábio L.; Thomaz, Edivaldo L.; Bastos, Rodrigo Oliveira

    2015-01-01

    Physical and chemical properties of soils play a major role in the evaluation of different geochemical signature, soil quality, discrimination of land use type, soil provenance and soil degradation. The objectives of the present study are the soil elemental characterization and soil differentiation in topographic sequence and depth, using Energy Dispersive X-Ray Fluorescence (EDXRF) as well as gamma-ray spectrometry data combined with Principal Component Analysis (PCA). The study area is an agricultural region of Boa Vista catchment which is located at Guamiranga municipality, Brazil. PCA analysis was performed with four different data sets: spectral data from EDXRF, spectral data from gamma-ray spectrometry, concentration values from EDXRF measurements and concentration values from gamma-ray spectrometry. All PCAs showed similar results, confirmed by hierarchical cluster analysis, allowing the data grouping into top, bottom and riparian zone samples, i.e. the samples were separated due to its landscape position. The two hillslopes present the same behavior independent of the land use history. There are distinctive and characteristic patterns in the analyzed soil. The methodologies presented are promising and could be used to infer significant information about the region to be studied. - Highlights: • Characterization of topographic sequence of two hillslopes from agricultural soil. • Employment of EDXRF and gamma-ray spectrometry data combined with PCA. • The combination of green analytical methodologies with chemometric studies allowed soil differentiation. • The innovative methodology is promising for direct characterization of agricultural catchments

  17. Fully automated gamma spectrometry gauge observing possible radioactive contamination of melting-shop samples

    International Nuclear Information System (INIS)

    Kroos, J.; Westkaemper, G.; Stein, J.

    1999-01-01

    At Salzgitter AG, several monitoring systems have been installed to check the scrap transport by rail and by car. At the moment, the scrap transport by ship is reloaded onto wagons for monitoring afterwards. In the future, a detection system will be mounted onto a crane for a direct check on scrap upon the departure of ship. Furthermore, at Salzgitter AG Central Chemical Laboratory, a fully automated gamma spectrometry gauge is installed in order to observe a possible radioactive contamination of the products. The gamma spectrometer is integrated into the automated OE spectrometry line for testing melting shop samples after performing the OE spectrometry. With this technique the specific activity of selected nuclides and dose rate will be determined. The activity observation is part of the release procedure. The corresponding measurement data are stored in a database for quality management reasons. (author)

  18. Improvements in Applied Gamma-Ray Spectrometry with Germanium Semiconductor Detector

    Energy Technology Data Exchange (ETDEWEB)

    Brune, D; Hellstroem, S [AB Atomenergi, Nykoeping (Sweden); Dubois, J [Chalmers University of Technology, Goeteborg (Sweden)

    1965-01-15

    A germanium semi-conductor detector has in the present investigation been used in four cases of applied gamma-ray spectrometry. In one case the weak-activity contribution of Cs{sup 134} in Cs{sup 137} standard sources has been determined. The second case concerns the determination of K{sup 42} in samples of biological origin containing strong Na{sup 24} activities. In the third case the Nb{sup 94} and Nb{sup 95} activities from neutron-irradiated niobium foils used in the dosimetry of high neutron fluxes with long exposure times have been completely resolved and it has been possible to determine the ratio of the two activities with a high degree of accuracy. Finally, a Zr{sup 95} - Nb{sup 95} source has been analysed in a similar way with respect to its radiochemical composition. The resolution obtained also made possible a determination of the branching ratio of the two gamma-transitions in Zr{sup 95} and of the energies of the gamma-transitions of both nuclides.

  19. Development of isotope dilution gamma-ray spectrometry for plutonium analysis

    Energy Technology Data Exchange (ETDEWEB)

    Li, T.K.; Parker, J.L. (Los Alamos National Lab., NM (United States)); Kuno, Y.; Sato, S.; Kurosawa, A.; Akiyama, T. (Power Reactor and Nuclear Fuel Development Corp., Tokai, Ibaraki (Japan))

    1991-01-01

    We are studying the feasibility of determining the plutonium concentration and isotopic distribution of highly radioactive, spent-fuel dissolver solutions by employing high-resolution gamma-ray spectrometry. The study involves gamma-ray plutonium isotopic analysis for both dissolver and spiked dissolver solution samples, after plutonium is eluted through an ion-exchange column and absorbed in a small resin bead bag. The spike is well characterized, dry plutonium containing {approximately}98% of {sup 239}Pu. By using measured isotopic information, the concentration of elemental plutonium in the dissolver solution can be determined. Both the plutonium concentration and the isotopic composition of the dissolver solution obtained from this study agree well with values obtained by traditional isotope dilution mass spectrometry (IDMS). Because it is rapid, easy to operate and maintain, and costs less, this new technique could be an alternative method to IDMS for input accountability and verification measurements in reprocessing plants. 7 refs., 4 figs., 4 tabs.

  20. Research on 3-D terrain correction methods of airborne gamma-ray spectrometry survey

    International Nuclear Information System (INIS)

    Liu Yanyang; Liu Qingcheng; Zhang Zhiyong

    2008-01-01

    The general method of height correction is not effectual in complex terrain during the process of explaining airborne gamma-ray spectrometry data, and the 2-D terrain correction method researched in recent years is just available for correction of section measured. A new method of 3-D sector terrain correction is studied. The ground radiator is divided into many small sector radiators by the method, then the irradiation rate is calculated in certain survey distance, and the total value of all small radiate sources is regarded as the irradiation rate of the ground radiator at certain point of aero- survey, and the correction coefficients of every point are calculated which then applied to correct to airborne gamma-ray spectrometry data. The method can achieve the forward calculation, inversion calculation and terrain correction for airborne gamma-ray spectrometry survey in complex topography by dividing the ground radiator into many small sectors. Other factors are considered such as the un- saturated degree of measure scope, uneven-radiator content on ground, and so on. The results of for- ward model and an example analysis show that the 3-D terrain correction method is proper and effectual. (authors)

  1. Measuring the radium quartet ({sup 228}Ra, {sup 226}Ra, {sup 224}Ra, {sup 223}Ra) in seawater samples using gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Beek, P. van, E-mail: vanbeek@legos.obs-mip.f [LEGOS, Laboratoire d' Etudes en Geophysique et Oceanographie Spatiales (CNRS/CNES/IRD/UPS), Observatoire Midi Pyrenees, 14 Avenue Edouard Belin, 31400 Toulouse (France); Souhaut, M. [LEGOS, Laboratoire d' Etudes en Geophysique et Oceanographie Spatiales (CNRS/CNES/IRD/UPS), Observatoire Midi Pyrenees, 14 Avenue Edouard Belin, 31400 Toulouse (France); Reyss, J.-L. [LSCE, Laboratoire des Sciences du Climat et de l' Environnement (CNRS/CEA/UVSQ), Avenue de la Terrasse, 91198 Gif-sur-Yvette (France)

    2010-07-15

    Radium isotopes are widely used in marine studies (eg. to trace water masses, to quantify mixing processes or to study submarine groundwater discharge). While {sup 228}Ra and {sup 226}Ra are usually measured using gamma spectrometry, short-lived Ra isotopes ({sup 224}Ra and {sup 223}Ra) are usually measured using a Radium Delayed Coincidence Counter (RaDeCC). Here we show that the four radium isotopes can be analyzed using gamma spectrometry. We report {sup 226}Ra, {sup 228}Ra, {sup 224}Ra, {sup 223}Ra activities measured using low-background gamma spectrometry in standard samples, in water samples collected in the vicinity of our laboratory (La Palme and Vaccares lagoons, France) but also in seawater samples collected in the plume of the Amazon river, off French Guyana (AMANDES project). The {sup 223}Ra and {sup 224}Ra activities determined in these samples using gamma spectrometry were compared to the activities determined using RaDeCC. Activities determined using the two techniques are in good agreement. Uncertainties associated with the {sup 224}Ra activities are similar for the two techniques. RaDeCC is more sensitive for the detection of low {sup 223}Ra activities. Gamma spectrometry thus constitutes an alternate method for the determination of short-lived Ra isotopes.

  2. A new approach for the high-precision determination of the elemental uranium concentration in uranium ore by gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Nagel, W.; Quik, F.

    1993-01-01

    A new approach for the determination of elemental uranium in uranium bearing ore, using high resolution gamma-ray spectrometry, was applied. Using a variant of the enrichment meter technique an agreement of better than 1% has been obtained between gamma-ray measurement results and the certified value obtained by other analytical methods. For the calibration of the gamma-ray spectrometer uranium reference samples have been used which are made available jointly in Europe and the USA as Certified Reference Materials for Gamma-ray Spectrometry (EC NRM 171 and NBS SRM 969, respectively). The measured ore has been put in a special designed container which ensured in all directions seen from the radiation window a uniform degree of infinite thickness of about 95%. The measurement results can be taken as an example for the applicability of gamma-ray spectrometry when high accuracy is required and under conditions where homogeneous distributed elemental uranium is embedded in a larger amount of matrix material. (author). 8 refs., 10 figs., 2 tabs., 2 appendices

  3. The gamma spectrometry a powerful tool for irradiated fuel and fission products release studies

    International Nuclear Information System (INIS)

    Pontillon, Y.; Roure, C.; Lacroix, B.; Martella, T.; Ducros, G.; Ravel, S.; Gleizes, B.

    2003-01-01

    Over the last decades, due to the potentially severe consequences of a nuclear incident and/or accident for surrounding populations as well as the environment, international safety authorities launched R and D programs in support of general policy on exploitation of nuclear energy. This increasing interest enabled starting of many research programs in CEA and particularly in Nuclear Energy Directorate (DEN). Most of them are devoted to (i) the source term of fission products (including gas) and actinides released from PWR fuel samples in normal or accident conditions, (ii) burn-up determination, (iii) isotopic repartition... by quantitative gamma spectrometry. In this context, the Department of Fuel Studies (DEC), part of the DEN, has acquired considerable experience in this field of research. In order to attain the required capabilities, specific technical facilities set up in shielded hot cells at the CEA-Grenoble and CEA-Cadarache have been developed. In particular, the researchers of the Department have developed several gamma scanning benches and a set of two thermal treatment devices, including the so-called 'VERCORS facility'. These devices are associated to on line quantitative gamma spectrometry, in order to measure emitted gas and fission products (FPs). The greatest asset of such installations is to ensure a high analytical experiments rate, and as a consequence to make parametrical approach of planned studies easier. The first part of the present communication focuses, on the one hand, on the peculiar aspects of the gamma spectrometry applied on irradiated fuel, mad on the other hand, on the technical aspect of the different facilities (i.e. quantitative gamma spectrometry apparatus and corresponding 'home made' software). The last part is devoted to the results which can be obtained with such installation. In particular, it will be explained how experimental programs on FPs and gas release in normal and/or accidental conditions can be conducted

  4. Comparative study of the gamma spectrometry method performance in different measurement geometries

    International Nuclear Information System (INIS)

    Diaconescu, C.; Ichim, C.; Bujoreanu, L.; Florea, I.

    2013-01-01

    This paper presents the results obtained by gamma spectrometry on aqueous liquid waste sample using different measurement geometries. A liquid waste sample with known gamma emitters content was measured in three different geometries in order to assess the influence of the geometry on the final results. To obtain low measurement errors, gamma spectrometer was calibrated using a calibration standard with the same physical and chemical characteristics as the sample to be measured. Since the calibration was performed with the source at contact with HPGe detector, the waste sample was also measured, for all the three geometries, at the detector contact. The influence of the measurement geometry on the results was evaluated by computing the relative errors. The measurements performed using three different geometries (250 ml plastic vial, Sarpagan box and 24 ml Tricarb vial) showed that all these geometries may be used to quantify the activity of gamma emitters in different type of radioactive waste. (authors)

  5. Radioactivity Measurement in the Detergent Products by Gamma Spectrometry

    International Nuclear Information System (INIS)

    Ksouri, Abir

    2009-01-01

    Our study focuses on the evaluation of the level of radioactivity in the detergents. We have determined the specific activities of gamma emitting radionuclides belonging to the natural families of uranium, thorium and potassium using gamma spectrometry. The activities of radionuclides ( 235 U, 238U , 226 Ra, 232 Th, 40K) and their descendants are below the minimum detectable activity for dishwasher products, soaps, bleaches and shampoos, whereas they are found to levels considered very low (between 0,2 and 13 Bq/kg on average) in the products washes linens. These values are always lower than those of raw materials, what is explained by the conservation of radioactive material throughout the manufacturing process. The effective dose due to external exposure estimated below the regulatory standard recommended (<1 mSv / year), allows us to show that detergent products are not contaminated by radioactivity, are healthy and do not have harmful radiological impact on the consumer.

  6. Results and comments on the gamma spectrometry examinations carried out on PWR and fast neutron fuel elements

    International Nuclear Information System (INIS)

    Pineira, Thomas; Mouchnino, Michel; Juste, Guy; Vignesoult, Nicole.

    1980-05-01

    The gamma spectrometry analyses on the fuel elements of PWR and fast neutron systems have experienced a significant growth in the CEA. This nondestructive, quick, inexpensive and quantitative method, seems to us particularly advantageous for qualifying the behavior of fuel under irradiation. However, in order to use it to the maximum, it must have reached a high degree of automation and the interpretation of the results must be the outcome of a coherent team that includes gamma spectrometry and fuel element specialists, since the growth of hot cell gamma spectrometry involves the processing of a considerable number of data upon which the quality of the results depends (large number of spectra per pencil analyzed, dimension of the 2000 or 4000 channel spectra, number of lines studied, etc.). Therefore the need to make the most of the information and, in particular, to present the results in a form suitable for direct processing in a minimum response time, requires a highly automated system. Further, the more specific results of gamma spectrometry correlated to the metallurgical results obtained in the laboratories should contribute efficiently to obtaining major information [fr

  7. The environmental radiation monitoring system and in-situ measurements for early notification and OIL (Operational Intervention Levels) calculations

    International Nuclear Information System (INIS)

    Haquin, G.; Ne'eman, E.; Brenner, S.; Lavi, N.

    1997-01-01

    The efficiency of the environmental radiation monitoring, low level laboratory and in-situ gamma-ray spectrometry are evaluated as the systems for early notification and for determination of dose rate in air, surface contamination and activity concentration in food during emergencies for Operational Intervention Levels (OIL) recalculation.The National Environmental Radiation Monitoring System has proved its efficiency in the early detection of unregistered radiography work. A mobile station of the network can be used for absorbed dose rate measurement during emergencies in contaminated areas. The calibrated in-situ gamma-ray spectrometry system in an open phosphate ore mine has showed the efficiency of this technique for fast and accurate determination of soil activity concentration. The calibration for an uniform depth distribution can be easily mathematically converted to an exponential depth distribution in cases of radioactive material fallout

  8. Correction for decay during counting in gamma spectrometry

    International Nuclear Information System (INIS)

    Nir-El, Y.

    2013-01-01

    A basic result in gamma spectrometry is the count rate of a relevant peak. Correction for decay during counting and expressing the count rate at the beginning of the measurement can be done by a multiplicative factor that is derived from integrating the count rate over time. The counting time substituted in this factor must be the live time, whereas the use of the real-time is an error that underestimates the count rate by about the dead-time (DT) (in percentage). This error of underestimation of the count rate is corroborated in the measurement of a nuclide with a high DT. The present methodology is not applicable in systems that include a zero DT correction function. (authors)

  9. In-situ gammaspectrometry intercomparison exercise in Salzburg/Austria

    International Nuclear Information System (INIS)

    Steger, F.; Lovranich, E.; Lettner, H.; Andrasi, A.

    1996-01-01

    In-situ gamma-spectrometry has become a useful method of assessing the nuclide concentrations of man-made and natural gamma-emitters in the soil. For the quality assurance of the measurements, periodically conducted intercomparison exercises are essential. Therefore exercises were organized in different European countries since 1990, the last one was conducted in Salzburg /Austria in September 1994. The participation of 24 measurement-teams from all over Europe emphasizes the importance of the intercomparison. Salzburg was selected because the Province of Salzburg /Austria was among the most heavily contaminated regions outside the former USSR by the Chernobyl fallout. Two different typical sites were selected for the measurements: Site 1 was inside the urban area of Salzburg on intensively used grassland which had not been tilled since the deposition of the fallout. This site is representative for intensively used agricultural regions in the Province of Salzburg. Site 2 was in the mountainous regions of the Hohe Tauern at an elevated altitude of 1600 m, representing the agricultural soil- and contamination conditions of the Alpine regions in the Tauern. The two sites differ significantly in terms of soil characteristics, a crucial parameter for the evaluation of in-situ gamma-spectra. The participants used different approaches for the evaluation of the gamma-spectra in terms of considering the depth distribution. In the paper the results from the 24 European teams are presented. (author)

  10. Fast-ion energy resolution by one-step reaction gamma-ray spectrometry

    DEFF Research Database (Denmark)

    Salewski, Mirko; Nocente, M.; Gorini, G.

    2016-01-01

    The spectral broadening of γ-rays from fusion plasmas can be measured in high-resolution gamma-ray spectrometry (GRS). We derive weight functions that determine the observable velocity space and quantify the velocity-space sensitivity of one-step reaction high-resolution GRS measurements in magne...

  11. Carborne gamma-ray spectrometry. Calibration and applications

    International Nuclear Information System (INIS)

    Aage, H.K.; Korsbech, U.; Bargholz, K.; Hovgaard, J.

    2006-01-01

    Calibration of carborne gamma-ray spectrometry systems for 137 Cs is carried out with a source successively placed at 791 positions within an area of 34 mx62 m. A computer model supplements the measurements. Hereby a sensitivity map for a surface contamination is generated as well as line and area sensitivities. Another model converts surface sensitivity to sensitivity for a deep contamination. Use of the sensitivity map for a non-homogeneous distribution of 137 Cs is demonstrated. Applications of line sensitivities for special tasks are discussed

  12. Study on the Effects of Sample Density on Gamma Spectrometry System Measurement Efficiency at Radiochemistry and Environment Laboratory

    International Nuclear Information System (INIS)

    Wo, Y.M.; Dainee Nor Fardzila Ahmad Tugi; Khairul Nizam Razali

    2015-01-01

    The effects of sample density on the measurement efficiency of the gamma spectrometry system were studied by using four sets multi nuclide standard sources of various densities between 0.3 - 1.4 g/ ml. The study was conducted on seven unit 25 % coaxial HPGe detector gamma spectrometry systems in Radiochemistry and Environment Laboratory (RAS). Difference on efficiency against gamma emitting radionuclides energy and measurement systems were compared and discussed. Correction factor for self absorption caused by difference in sample matrix density of the gamma systems were estimated. The correction factors are to be used in quantification of radionuclides concentration in various densities of service and research samples in RAS. (author)

  13. A new method for the determination of radionuclide distribution in the soil by in situ gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Zombori, P.; Andrasi, A.; Nemeth, I.

    1995-01-01

    In case of major nuclear accidents when larger amount of radioactive material is released into the atmosphere vast areas can become contaminated by the nuclear fallout. The deposited radioactivity penetrates the soil in a complex manner: dry and wet deposition lead to different initial distribution patterns which are further modified by the later transport processes in the upper layers of the soil. The distribution is influenced by various factors (physico-chemical characteristics of the radioisotopes, soil type, weather conditions, environment etc.), the resulting soil profile is hardly predictable. An important lesson we learned from the Chernobyl reactor accident is the great variability of the contamination both in the extent of the deposition and in the penetration features. In recent years - following the reactor accident in Chernobyl - an increased interest for rapid methods of monitoring environmental radioactivity was expressed. The International Atomic Energy Agency initiated a research project to co-ordinate the activities carried out in various laboratories aiming at the development of rapid monitoring procedures. The Co-ordinated Research Project (CRP) G6 10 01 under the title Rapid Instrumental and Separation Methods for Monitoring Radionuclides in Food and the Environment has given a frame for 11 research programs. The Health Physics Department of the KFKI Institute for Atomic Energy Research (the former Central Research Institute for Physics) has taken a part in this CRP with a project titled: Rapid In Situ Gamma Spectrometric Determination of Fallout Radioactivity in the Environment. The main objective of our study was to find a method to estimate the penetration characteristics of the fallout radioactivity by using only spectral information obtained by the in situ spectrometric measurement thus avoiding the need for a long and tiresome sampling and sample analysis procedure

  14. Collection and preparation of samples for gamma spectrometry

    International Nuclear Information System (INIS)

    Pan Jingquan

    1994-01-01

    The paper presents the basic principles of sample collection and preparation: setting up unified sampling program, methods and procedures, sample packing, transportation and storage, determination of sample quantity, sample pretreatment and preparation of samples to be analysed, etc. for gamma spectrometry. And the paper also describes briefly the main methods and special issues of sampling and preparation for the same environmental and biological samples, such as, air, water, grass, soil and foods

  15. Catalogue of response spectra for unfolding in situ gamma-ray pulse-height distributions

    International Nuclear Information System (INIS)

    Dymke, N.

    1982-01-01

    To unfold in situ gamma-ray pulse-height distributions by means of a response matrix technique, the matrix must be in keeping with the measurement geometry, detector size, and energy range to be covered by the measurements. A methodology has been described for determination of standard gamma-ray spectra needed in deriving response matrices and a spectrum catalogue compiled containing graphs and data for the 0-3 MeV (4 x 4 in. NaI(Tl)) and 0-8 MeV (1.5 x 1.5 in. NaI(Tl)) ranges. (author)

  16. Determination of 7BE in soil sample by gamma spectrometry for erosion researchs

    International Nuclear Information System (INIS)

    Esquivel, Alexander D.; Kastner, Geraldo F.; Amaral, Angela M.; Monteiro, Roberto Pellacani G.; Moreira, Rubens M.

    2015-01-01

    Cosmogenic 7 Be is a natural radiotracer produced in the stratosphere and troposphere and reached to the Earth surface via wet and dry fallout and hence its measurement for research of erosion in soils is very significant. The 7 Be radio analyse based on gamma spectrometry technique has been a routine methodology for decades and although is the reference procedure is not free of analytical interference. 7 Be is a β-γ emitting radionuclide (Eγ = 477.59 keV, T½ = 53.12d) and depending on the chemical profile of the soil its determination is susceptible to 228 Ac (E γ = 478.40 keV, T½ = 6.15h) interference. The aim of this work was to establish an analytical protocol for the 7 Be determination in soil samples from Juatuba-Mg region in different sampling periods of dry and rainy seasons for erosion studies and to establish some methodologies for evaluating and correcting the interference level of 228 Ac in the 7 Be activity measurements by gamma spectrometry. (author)

  17. Spent fuel scanning using the gamma spectrometry bench at Osiris. Power and burnup determination

    International Nuclear Information System (INIS)

    Cerles, J.-M.; Simonet, Genevieve.

    1976-01-01

    The Saclay Nuclear Research Center is provided with an original gamma spectrometry facility located inside the pool of the Osiris reactor. It is intended for the gamma scanning of fuel elements irradiated in Osiris or elements of any other origin. The principal characteristics of this facility are given. Special emphasis is put on its [fr

  18. Mobile gamma spectrometry. Evaluation of the Resume 99 exercise

    International Nuclear Information System (INIS)

    Mellander, H.; Karlsson, S.; Aage, H.K.; Korsbech, U.; Lauritzen, B.; Smethurst, M.

    2002-06-01

    During the RESUME 99 exercise, the radiocaesium ( 137 Cs) activity in the surroundings of Gavle in central Sweden was ma p ped using car-borne gamma-ray spectrometry (CGS). The CGS data along with airborne gamma-ray spectrometry (AGS) data from the same area have been used to examine possible correlations between the CGS and AGS results, detector type and position, and geographical information, such as land-use and road type. The overall differences between various CGS results are small, while larger differences are found between AGS and CGS results. In general only little correlation was found with land-use and with road-type and width. The differences between AGS and CGS results arise because airborne detectors have a different field of view than a ground-based detector. From an analysis of the depth-dependency of AGS and CGS data for a depth-distributed source, it is found that the mean mass depth may be inferred from the ratio of AGS to CGS spectral count rates. Integration of AGS and CGS data requires a precise definition of quantities and units for reporting activity concentrations in a complicated geometry and care must be taken to translate AGS results into equivalent CGS quantities taking into account the spatial distribution of the radionuclides. (au)

  19. Mobile gamma spectrometry. Evaluation of the Resume 99 exercise

    Energy Technology Data Exchange (ETDEWEB)

    Mellander, H.; Karlsson, S. [Swedish Radiation Protection Authority, Stockholm (Sweden); Aage, H.K.; Korsbech, U. [Technical Univ. of Denmark, Lyngby (Denmark); Lauritzen, B. [Risoe National Laboratory, Roskilde (Denmark); Smethurst, M. [Geological Survey of Norway, Trondheim (Norway)

    2002-06-01

    During the RESUME 99 exercise, the radiocaesium ({sup 137}Cs) activity in the surroundings of Gavle in central Sweden was ma{sup p}ped using car-borne gamma-ray spectrometry (CGS). The CGS data along with airborne gamma-ray spectrometry (AGS) data from the same area have been used to examine possible correlations between the CGS and AGS results, detector type and position, and geographical information, such as land-use and road type. The overall differences between various CGS results are small, while larger differences are found between AGS and CGS results. In general only little correlation was found with land-use and with road-type and width. The differences between AGS and CGS results arise because airborne detectors have a different field of view than a ground-based detector. From an analysis of the depth-dependency of AGS and CGS data for a depth-distributed source, it is found that the mean mass depth may be inferred from the ratio of AGS to CGS spectral count rates. Integration of AGS and CGS data requires a precise definition of quantities and units for reporting activity concentrations in a complicated geometry and care must be taken to translate AGS results into equivalent CGS quantities taking into account the spatial distribution of the radionuclides. (au)

  20. A comparative study of 232Th and 238U activity estimation in soil samples by gamma spectrometry and Neutron Activation Analysis (NAA) technique

    International Nuclear Information System (INIS)

    Rekha, A.K.; Anilkumar, S.; Narayani, K.; Babu, D.A.R.

    2012-01-01

    Radioactivity in the environment is mainly due to the naturally occurring radionuclides like uranium, thorium with their daughter products and potassium. Even though Gamma spectrometry is the most commonly used non destructive method for the quantification of these naturally occurring radionuclides, Neutron Activation Analysis (NAA), a well established analytical technique, can also be used. But the NAA technique is a time consuming process and needs proper standards, proper sample preparation etc. In this paper, the 232 Th and 238 U activity estimated using gamma ray spectrometry and NAA technique are compared. In the case of direct gamma spectrometry method, the samples were analysed after sealing in a 250 ml container. Whereas for the NAA, about 300 mg of each sample, after irradiation were subjected to gamma spectrometry. The 238 U and 232 Th activities (in Bq/kg) in samples were estimated after the proper efficiency correction and were compared. The estimated activities by these two methods are in good agreement. The variation in 238 U and 232 Th activity values are within ± 15% which are acceptable for environmental samples

  1. The central gamma spectrometry laboratory of the GSF Institute of Radiation Protection

    International Nuclear Information System (INIS)

    Ruckerbauer, F.; Dietl, F.; Winkler, R.

    1997-01-01

    Since the middle of 1995 the WG Radioecology is operating the central gamma spectrometry laboratory of the GSF-Institute of Radiation Protection. The main scope of the laboratory is the gamma spectrometric analysis of samples within the research program of the institute and within joint programs with other institutes of the GSF research center. In the present report set-up and technical data of the measuring equipment, the central operating and data evaluation system and measures for quality assurance are described. At that time 18 semiconductor detectors are available for gamma spectrometric sample analysis which is standardized with respect to operation, evaluation algorithms, nuclide data, data safety and documentation. (orig.) [de

  2. Laboratory of High resolution gamma spectrometry; Laboratorio de espectrometria gamma de alta resolucion

    Energy Technology Data Exchange (ETDEWEB)

    Mendez G, A.; Giber F, J.; Rivas C, I.; Reyes A, B

    1992-01-15

    The Department of Nuclear Experimentation of the Nuclear Systems Management requests the collaboration of the Engineering unit for the supervision of the execution of the work of the High resolution Gamma spectrometry and low bottom laboratory, using the hut of the sub critic reactor of the Nuclear Center of Mexico. This laboratory has the purpose of determining the activity of special materials irradiated in nuclear power plants. In this report the architecture development, concepts, materials and diagrams for the realization of this type of work are presented. (Author)

  3. Determination of radon concentration in soil gas by gamma-ray spectrometry of olive oil

    International Nuclear Information System (INIS)

    Al-Azmi, Darwish; Karunakara, N.

    2007-01-01

    Measurements of radon concentration in soil gas have been carried out using a bubbling system in which the soil gas is drawn through an active pumping to bubble a liquid absorber (olive oil) for the deposition of the soil gas in it. After the bubbling process, the absorber is then taken for gamma-ray measurements. Gamma-ray photopeaks from the 214 Pb and the 214 Bi radon progeny are considered for the detection of the 222 Rn gas to study the concentration levels for radon soil gas. Results for some field measurements were obtained and compared with results obtained using AlphaGuard radon gas monitor. The technique provides a possible approach for the measurements of radon soil gas with gamma-ray spectrometry

  4. Airborne gamma-ray spectrometry and computer data processing

    International Nuclear Information System (INIS)

    Raghuwanshi, S.S.; Bhishma Kumar; Tewari, S.G.

    1993-01-01

    The physical basis for the measurement of radioelemental concentrations of U, Th, and K on the surface of the earth by airborne gamma-ray spectrometry (AGRS) are described in this paper. The yield of an infinite radioactive plane source for a particular gamma energy helps to know the sampled volume in AGRS, the ground coverage, the ground resolution, the effective planning of the survey, flight line spacing, and sampling time. The infinite source-yield enables the determination of the attenuation coefficients in actual surveys and lays down the criteria for a standard test strip. Scattering of gamma-rays in matter is discussed in order to study its influence in the measurements from air. The theoretical gamma-ray spectrum from terrestrial U, Th, and K are discussed in contrast to its realistic picture which poses problems for their direct use for measurements. The criterion of FWHM (full width at half maximum) and inter-energy distance with their yields is described which finally helps to select the energy windows for (window and MCA) AGRS system. Factors which affect the measurements of radioelemental concentration in AGRS surveys include both correctable and non-correctable ones. Correctable factors are : (a) non-terrestrial sources of gamma-rays aircraft, cosmic, and airborne background (H) (B); (b) interference due to gamma-scattering inter channel effects (l); (c) height variations (H) due to navigation and topography; (d) temperature (T) of ambient air; and (e) pressure (P) of air at flying altitude. For removal of background effects, measurements over test strip and calibration pads are necessary for making the corrections in the order - BIH. These methods are described in the paper. The non-correctable factors include effects, due to terrain moisture, vegetation, and others. The possible ways to eliminate these effects are also briefly described. (author). 17 refs., 13 figs

  5. Composite mapping experiences in airborne gamma spectrometry

    International Nuclear Information System (INIS)

    Bucher, B.

    2014-01-01

    During an international intercomparison exercise of airborne gamma spectrometry held in Switzerland 2007 teams from Germany, France and Switzerland were proving their capabilities. One of the tasks was the composite mapping of an area around Basel. Each team was mainly covering the part of its own country at its own flying procedures. They delivered the evaluated data in a data format agreed in advance. The quantities to be delivered were also defined in advance. Nevertheless, during the process to put the data together a few questions raised: Which dose rate was meant? Had the dose rate to be delivered with or without cosmic contribution? Activity per dry or wet mass? Which coordinate system was used? Finally, the data could be put together in one map. For working procedures in case of an emergency, quantities of interest and exchange data format have to be defined in advance. But the procedures have also to be proved regularly. (author)

  6. The environmental radiation monitoring system and in-situ measurements for early notification and OIL (Operational Intervention Levels) calculations

    Energy Technology Data Exchange (ETDEWEB)

    Haquin, G.; Ne`eman, E.; Brenner, S.; Lavi, N. [Tel Aviv Univ. (Israel). Sackler School of Medicine. Inst. for Environmental Research

    1997-12-31

    The efficiency of the environmental radiation monitoring, low level laboratory and in-situ gamma-ray spectrometry are evaluated as the systems for early notification and for determination of dose rate in air, surface contamination and activity concentration in food during emergencies for Operational Intervention Levels (OIL) recalculation.The National Environmental Radiation Monitoring System has proved its efficiency in the early detection of unregistered radiography work. A mobile station of the network can be used for absorbed dose rate measurement during emergencies in contaminated areas. The calibrated in-situ gamma-ray spectrometry system in an open phosphate ore mine has showed the efficiency of this technique for fast and accurate determination of soil activity concentration. The calibration for an uniform depth distribution can be easily mathematically converted to an exponential depth distribution in cases of radioactive material fallout 7 refs., 3 figs., 1 tab.; e-mail: envirad at post.tau.ac.il; env{sub r}ad at netvision,net.il

  7. Control of quality in spectrometry gamma of low level

    CERN Document Server

    Salazar, A

    1997-01-01

    Low level gamma spectrometry is a very precise technique to measure the concentration of nuclides present in different samples in Bq kg sup - sup 1. The quality control of the procedure and method used can be carried out by intercomparison exercises with world recognized institutions. During the last three years the Nuclear Physics Laboratory Of The University of Costa Rica (LAFNA) has been participating in the international quality assessment program (QAP) carried out by the Environmental Measurements Laboratory (EML), department of Energy, USA. The results show a very good agreement with the rest of the participant laboratories. This provides a very objective evaluation of the high precision of the methods used by LAFNA in low level spectroscopy measurements. (Author)

  8. Control of quality in spectrometry gamma of low level

    International Nuclear Information System (INIS)

    Salazar, A.; Loria, G.

    1997-01-01

    Low level gamma spectrometry is a very precise technique to measure the concentration of nuclides present in different samples in Bq kg -1 . The quality control of the procedure and method used can be carried out by intercomparison exercises with world recognized institutions. During the last three years the Nuclear Physics Laboratory Of The University of Costa Rica (LAFNA) has been participating in the international quality assessment program (QAP) carried out by the Environmental Measurements Laboratory (EML), department of Energy, USA. The results show a very good agreement with the rest of the participant laboratories. This provides a very objective evaluation of the high precision of the methods used by LAFNA in low level spectroscopy measurements. (Author) [es

  9. Design and fabrication of shielding for gamma spectrometry; Diseno y fabricacion de blindaje para espectrometria gamma

    Energy Technology Data Exchange (ETDEWEB)

    Mariano H, E

    1991-05-15

    To have a system of gamma spectrometry in the Radiological Mobile Unit No. 1 (UMOR-1) was designed and manufactured an armor-plating appropriate to this, to make analysis of radioactive samples in place in the event of a radiological emergency, besides being able to give support to the Management of Radiological Safety, and even to give service of sample analysis of other Institutions. (Author)

  10. Neutron induced gamma spectrometry for on-line compositional analysis in coal conversion and fluidized-bed combustion plants

    International Nuclear Information System (INIS)

    Herzenberg, C.L.; O'Fallon, N.M.; Yarlagadda, B.S.; Doering, R.W.; Cohn, C.E.; Porges, K.G.; Duffey, D.

    1977-01-01

    Nuclear techniques involving relatively penetrating radiation may offer the possibility of non-invasive, continuous on-line instrumental monitoring which is representative of the full process stream. Prompt gamma rays following neutron capture are particularly attractive because the penetrating power of the neutrons and the, typically several MeV, capture gammas makes possible interrogation of material within a pipe. We are evaluating neutron capture gamma techniques for this application, both for elemental composition monitoring and for mass-flow measurement purposes, and this paper will present some recent work on composition analysis by neutron induced gamma spectrometry

  11. Iterative inversion of gamma or alpha spectrometry data

    International Nuclear Information System (INIS)

    Nordemann, D.J.R.

    1985-12-01

    Gamma - and alpha ray spectrometry data are processed by an iterative regression method (Wolberg, 1967) to obtain the activities or yields of radionuclides. This method, applied to Nuclear Geophysics Research, permits the use of either selected energy bands or of all the channels one by one. It may be easily programmed in popular microcomputers and offers many advantages such as the use of mixtures of radionuclides for the calibrations and the treatment of the uncertainties on the measurements and results. Several conclusions about the method and options of nuclear data processing are presented. (Author) [pt

  12. In-situ gamma-analysis support for Phase I, Middlesex cleanup project, Middlesex, New Jersey

    International Nuclear Information System (INIS)

    Reiman, R.T.

    1983-07-01

    At the request of the Department of Energy, the Energy Measurements Group of EG and G participated in the Remedial Action program for the former Middlesex Sampling Plant and associated properties at Middlesex, New Jersey from July to November 1980. EG and G provided real time analysis of the radiological character of the soil of each property included in the Phase I cleanup before, during, and after decontamination. The method used for the analysis was in situ gamma spectroscopy employing a high purity germanium detector. This report describes the in situ system and displays the results of the in situ measurements before and after decontamination of the properties surveyed during Phase I

  13. Decision Threshold and Detection Limit in Spectrometric Measurements. Part 1: Application to Gamma Spectrometry

    International Nuclear Information System (INIS)

    Perez, C.; Gasco, C.; Lopez, M. A.

    2010-01-01

    This report summarised the author's lecture of the advanced gamma spectrometry course organised by CIEMAT. The characteristic limits determination in gamma spectrometry generally is obtained through the programming that the trade marks offers to the client with the objective of the automatic calculation of the activity concentrations existing in a sample. In this report, the examples shown in the ISO 11929 standard are compared to the programming realised by Genie 2k for determining characteristic limits. The main difference of both is located in the uncertainty calculations due to the efficiency calibration that is considered by ISO and not by Genie 2K. Through implementation in the software developed by trade marks will be possible to introduce this uncertainty and to assimilate to the calculation done by ISO 11929. In the second part of this report will be analyzed the more complicated samples of this application as counting in a whole body counter (following ISO-28218 about Performance Criteria for radio bioassay), multiplet, overlapping, addition of several peaks for obtaining the activity concentration, etc. (Author) 19 refs.

  14. In situ evaluation of radwaste gamma activities

    International Nuclear Information System (INIS)

    Dulama, Cristian; Toma, Al.; Dobrin, R.; Pavelescu, Margarit

    2003-01-01

    There are certain limitations concerning the usage of standard source method for efficiency calibration of gamma-ray spectrometers measuring in extended geometry conditions. These limitations arise from the great diversity of forms and sizes of the objects which are to be measured during decommissioning and radioactive waste management activities. The INR - Pitesti operates a radioactive waste management facilities for both its own necessities and for providing external services. This facility is able to perform conditioning of liquid and solid wastes for interim storage disposal. During the conditioning operations there are certain stages when the radioactive measurement of the storage drums is demanded. We developed a gamma ray spectrometry equipment using a portable MCA Canberra INSPECTOR, a HPGe detector and an INR manufactured collimator. We are using a semiempirical method to calibrate the gamma ray spectrometer for such measurements. A program was written in Visual Basic language and includes a graphical interface for parameters input and data output. The input parameters are stored in text files, which can be loaded, modified or saved on disk as desired. The program was tested to establish the stability of MC simulation and the sensitivity to the input parameters. During the programming process it was possible to verify some code sequences and the results obtained showed that the model used was appropriate. To find out the optimal number of MC histories, which have to be modelled to obtain results of sufficient accuracy, the program was repeatedly run by changing only the number of histories. The relative deviation to the mean of the effective solid angle was calculated. The density of the source material as well as its composition can be changed by input. For comparison the efficiency calibration curves for sources materials having the same elemental composition but different densities ranging from 10 to 1000 kg/m 3 are drawn. The activities of the

  15. Classification of soil samples according to their geographic origin using gamma-ray spectrometry and principal component analysis

    International Nuclear Information System (INIS)

    Dragovic, Snezana; Onjia, Antonije

    2006-01-01

    A principal component analysis (PCA) was used for classification of soil samples from different locations in Serbia and Montenegro. Based on activities of radionuclides ( 226 Ra, 238 U, 235 U, 4 K, 134 Cs, 137 Cs, 232 Th and 7 Be) detected by gamma-ray spectrometry, the classification of soils according to their geographical origin was performed. Application of PCA to our experimental data resulted in satisfactory classification rate (86.0% correctly classified samples). The obtained results indicate that gamma-ray spectrometry in conjunction with PCA is a viable tool for soil classification

  16. Determination of radium isotopes in environmental samples by gamma spectrometry, liquid scintillation counting and alpha spectrometry: a review of analytical methodology

    International Nuclear Information System (INIS)

    Jia, Guogang; Jia, Jing

    2012-01-01

    Radium (Ra) isotopes are important from the viewpoints of radiation protection and environmental protection. Their high toxicity has stimulated the continuing interest in methodology research for determination of Ra isotopes in various media. In this paper, the three most routinely used analytical techniques for Ra isotope determination in biological and environmental samples, i.e. low-background γ-spectrometry, liquid scintillation counting and α-spectrometry, were reviewed, with emphasis on new methodological developments in sample preparation, preconcentration, separation, purification, source preparation and measurement techniques. The accuracy, selectivity, traceability, applicability and minimum detectable activity (MDA) of the three techniques were discussed. It was concluded that the MDA (0.1 mBq L −1 ) of the α-spectrometry technique coupled with chemical separation is about two orders of magnitude lower than that of low-background HPGe γ-spectrometry and LSC techniques. Therefore, when maximum sensitivity is required, the α-spectrometry technique remains the first choice. - Highlights: ► A review is made for determination of Ra isotopes in environmental samples. ► Gamma spectrometry, LSC and a-spectrometry are the main concerned radiometric approach. ► Sample preparation, preconcentration, separation and source preparation are discussed. ► The methods can analyse air, water, seawater, soil, sediment and foodstuffs samples. ► Some new data obtained recently from our laboratory for Ra method study are included.

  17. Use of gamma spectrometry for analysis of three reference materials

    International Nuclear Information System (INIS)

    Kinova, L.

    2004-01-01

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

  18. Twenty years of experience in applying gamma spectrometry for NDT

    International Nuclear Information System (INIS)

    Meenakshisundaram, V.; Raghunath, V.M.

    1996-01-01

    A NDT technique using NaI(Tl) detector and Single Channel Analyser (SCA) based gamma ray spectrometer was developed to check the shielding integrity of lead poured vessels, for as low a specification as 2% tolerance. The method in detail, its advantages, and some of the interesting findings are described. This paper also highlights other possible in-situ applications like i) identifying cracks propagating in end shield of a Pressurised Heavy Water Reactor (PHWR) in the presence of high radiation field and ii) level estimation for liquids such as Na and NaK used in fast reactor storage tanks. (author)

  19. Application of in situ measurement for site remediation and final status survey of decommissioning KRR site

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sang Bum; Nam, Jong Soo; Choi, Yong Suk; Seo, Bum Kyoung; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-06-15

    In situ gamma spectrometry has been used to measure environmental radiation, assumptions are usually made about the depth distribution of the radionuclides of interest in the soil. The main limitation of in situ gamma spectrometry lies in determining the depth distribution of radionuclides. The objective of this study is to develop a method for subsurface characterization by in situ measurement. The peak to valley method based on the ratio of counting rate between the photoelectric peak and Compton region was applied to identify the depth distribution. The peak to valley method could be applied to establish the relation between the spectrally derived coefficients (Q) with relaxation mass per unit area (β) for various depth distribution in soil. The in situ measurement results were verified by MCNP simulation and calculated correlation equation. In order to compare the depth distributions and contamination levels in decommissioning KRR site, in situ measurement and sampling results were compared. The in situ measurement results and MCNP simulation results show a good correlation for laboratory measurement. The simulation relationship between Q and source burial for the source layers have exponential relationship for a variety depth distributions. We applied the peak to valley method to contaminated decommissioning KRR site to determine a depth distribution and initial activity without sampling. The observed results has a good correlation, relative error between in situ measurement with sampling result is around 7% for depth distribution and 4% for initial activity. In this study, the vertical activity distribution and initial activity of {sup 137}Cs could be identifying directly through in situ measurement. Therefore, the peak to valley method demonstrated good potential for assessment of the residual radioactivity for site remediation in decommissioning and contaminated site.

  20. Comparison of Pu isotopic composition between gamma and mass spectrometry: Experience from IAEA-SAL

    International Nuclear Information System (INIS)

    Parus, J.L.; Raab, W.

    1998-01-01

    About 2000 Pu containing samples have been analysed during the last 8 years at SAL using gamma spectrometry (GS) in parallel with mass spectrometry (MS). Four different detectors have been used for the measurement of gamma-ray spectra and several versions of the MGA program have been used for spectra evaluation. The results of Pu isotopic composition obtained by both methods have neem systematically compared. Attempts to improve the agreement between GS and MS are described. This was done by adjustment of the emission probabilities for some gamma energies and the development of a new correlation equation for 242 Pu. These improvements have been applied for evaluation of two sets containing 320 and 404 samples, respectively analysed in 1991 and in 1992-93. The mean differences and their standard deviations between MS and GS were calculated, showing mean relative differences for 238-241 Pu isotopes in the range from 0.1 to 0.5% with standard deviations within ± 0.4 to ±1%. For 242 Pu these values are about 0.5% and ± 5%, respectively. (author)

  1. Correlation analysis of measurement result between accelerator mass spectrometry and gamma counter

    International Nuclear Information System (INIS)

    Minamimoto, Ryogo; Cheng, C.; Oka, Takashi; Inoue, Tomio; Hamabe, Yoshimi; Shimoda, Marika

    2010-01-01

    The guidelines for microdosing in clinical trials were published in Japan in 2008 following the guidelines of the European Medicines Agency and the Food and Drug Administration. They recommend utilizing accelerator mass spectrometry (AMS) and positron emission tomography as candidates for monitoring drug metabolites in preclinical studies. We correlate the two methods by measuring appropriately labeled tissue samples from various mouse organs using both AMS and gamma counter. First, we measured the 14 C background levels in mouse organs using the AMS system. We then clarified the relationship between AMS and gamma counter by simultaneously administering 14 C-2-fluoro-2-deoxyglucose ( 14 C-FDG) and 18 F-2-fluoro-2-deoxyglucose ( 18 F-FDG). Tissue distribution was examined after 30 min, 1 h, 2 h and 4 h using the AMS system for 14 C-FDG and gamma counter for 18 F-FDG. Background 14 C levels were subtracted from the data obtained with radiotracer administration. The background 14 C concentration differed with tissue type measured. Background 14 C concentration in mouse liver was higher than in other organs, and was approximately 1.5-fold that in blood. The correlation coefficient (r) of the measurements between AMS ( 14 C-FDG) and gamma counter ( 18 F-FDG) was high in both normal (0.99 in blood, 0.91 in brain, 0.61 in liver and 0.78 in kidney) and tumor-bearing mice (0.95 in blood and 0.99 in tumor). The clearance profile of 18 F-FDG was nearly identical to that of 14 C-FDG measured with AMS. Accelerator mass spectrometry analysis has an excellent correlation with biodistribution measurements using gamma counter. Our results suggest that the combination of AMS and positron emission tomography (PET) can act as a complementary approach to accelerate drug development. (author)

  2. Study on the natural radioactivity from the region of Presidente Figueiredo (AM), Brazil, using gamma spectrometry

    International Nuclear Information System (INIS)

    Da Silva, Jose Ribamar Silveira

    1999-01-01

    A gamma spectrometry profile was carried out along BR174 highway, that crosses some lithostratigraphic units of the North portion of the Sedimentary Basin of Amazon. Measurements in situ were realized in 116 points, 1 km apart, using a GAD-6 gamma-spectrometer and samples of rocks and soils were collected in geologically representative points, for gamma measurements using a shielded detector of NaI(Tl) available in the Nuclear Geophysics Laboratory of IAG/USP. The criterion used for evaluating the reliability degree of the concentration values of eU (ppm), eTh (ppm) and %K was to establish mathematically detection limits, for all measurement points. Every these points had been located using GPS with accuracy of 50 m to become possible a future detailed study. The purpose of matching portable gamma spectrometer and laboratory determinations was to compare the 2 techniques, using the criterion of detectability limits, and to verify the influence of 222 Rn atmospheric radioactive gas in field measurements. In the case of portable detector, it allows fast measurements and the sensor 'sees' a big volume of material (rock, soil...), that makes it more representative. In some situations where atmospheric phenomena of thermal inversion occurs, measurement can be affected by the 222 Rn cosmic background. Presence of radon daughter elements, associated with aerosols, in this tropical environment (high values of temperature and humidity), where the speed of the wind that could exhaust this gas is practically zero. It is observed that the values of concentration in the some points, got with these 2 techniques, have the same trend, and the stretches where peaks of concentration of K also occur and U and Th are associated with the presence of granite out corps, great boulders, and clay soils from weathering of these rocks. (author)

  3. Determination Performance Of Gamma Spectrometry Co-Axial HPGE Detector In Radiochemistry And Environment Group, Nuclear Malaysia

    International Nuclear Information System (INIS)

    Mei-Woo, Y.

    2014-01-01

    Gamma Spectrometry System is used to measure qualitatively and quantitatively a gamma emitting radionuclide. The accuracy of the measurement very much depends on the performance specifications of the HPGe detectors. From this study it found that all the seven co-axial HPGe detectors in Radiochemistry and Environment Group, Nuclear Malaysia are in good working conditions base on the verification of performance specifications namely Resolution, Peak Shape, Peak-to-Compton ratio and Relative Efficiency against the warranted value from the manufacturers. (author)

  4. A simple method for the deconvolution of 134 Cs/137 Cs peaks in gamma-ray scintillation spectrometry

    International Nuclear Information System (INIS)

    Darko, E.O.; Osae, E.K.; Schandorf, C.

    1998-01-01

    A simple method for the deconvolution of 134 Cs / 137 Cs peaks in a given mixture of 134 Cs and 137 Cs using Nal(TI) gamma-ray scintillation spectrometry is described. In this method the 795 keV energy of 134 Cs is used as a reference peak to calculate the activity of the 137 Cs directly from the measured peaks. Certified reference materials were measured using the method and compared with a high resolution gamma-ray spectrometry measurements. The results showed good agreement with the certified values. The method is very simple and does not need any complicated mathematics and computer programme to de- convolute the overlapping 604.7 keV and 661.6 keV peaks of 134 Cs and 137 Cs respectively. (author). 14 refs.; 1 tab., 2 figs

  5. Composite mapping experiences in airborne gamma spectrometry.

    Science.gov (United States)

    Bucher, B

    2014-08-01

    During an international intercomparison exercise of airborne gamma spectrometry held in Switzerland 2007 teams from Germany, France and Switzerland were proving their capabilities. One of the tasks was the composite mapping of an area around Basel. Each team was mainly covering the part of its own country at its own flying procedures. They delivered the evaluated data in a data format agreed in advance. The quantities to be delivered were also defined in advance. Nevertheless, during the process to put the data together a few questions raised: Which dose rate was meant? Had the dose rate to be delivered with or without cosmic contribution? Activity per dry or wet mass? Which coordinate system was used? Finally, the data could be put together in one map. For working procedures in case of an emergency, quantities of interest and exchange data format have to be defined in advance. But the procedures have also to be proved regularly. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Some considerations on the use of gamma spectrometry for Kr-85 determination at gaseous effluents in the nuclear industry and environmental samples

    International Nuclear Information System (INIS)

    Heras Iniquez, M.C.; Perez Garcia, M.M.; Travesi, A.

    1983-01-01

    The possibilities of using high resolution gamma ray spectrometry with GeLi semiconductor detector for measured the 0.514 KeV gamma radiation of Kr-B5 la explored, The detection limit of Kr-85 for a measuring time is 4.10 - 4 μCi with a counting time of 1000 minutes in a GeLi detector with a 20% efficiency relative to the INa (Tl). It is concluded that the use of gamma ray spectrometry for measuring the Kr-85 is not useful for environmental samples, but it can be used for the Kr-85 effluents control in Nuclear Stations. (Author) 26 refs

  7. Natural radioactivity in iron and steel materials by low-level gamma spectrometry

    International Nuclear Information System (INIS)

    Tanase, G.; Tanase, Maria

    2003-01-01

    High resolution low-level gamma spectrometry was applied to perform a radioactivity measurement in iron and steel raw materials (coal, coke, iron ore, pellets, manganese ore, limestone, dolomite), auxiliary materials (scorialite, oxide of Ti, bentonite), and some related final products (cast iron, slag, blast-furnace, flue dust) involved in iron making processing. We control the activity of materials in various kinds of samples and we investigate for transfer of radioactivity during the blast-furnace process. Artificial radioisotopes are rarely encountered. (authors)

  8. Investigation of environmental samples by low-level gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Koehler, M [Nuclear Engineering and Analytics Rossendorf, Inc., Dresden (Germany); Niese, S [Nuclear Engineering and Analytics Rossendorf, Inc., Dresden (Germany)

    1997-03-01

    The average sample number in our laboratory is about 200 per month (12% technical solid state, 30% geological solid state, 6% geological solid state with low mass, 12% biological, 11% water directly, 25% water after chemical separation, 4% others). In 54% of the measurements the background continuum, and though the detection limit, is determined only by the detector himself and not by the compton continuum from high energy lines in the sample. Some examples in the presented work aim to prove the advantages of gamma ray spectrometry in the underground laboratory Felsenkeller. (orig./DG)

  9. Several experimental applications of gamma ray spectrometry on the analysis of uranium compounds

    International Nuclear Information System (INIS)

    Korob, Ricardo O.; Blasiyh Nuno, Guillermo A.

    2002-01-01

    Several experimental applications of gamma ray spectrometry on the analysis of uranium compounds and materials containing it are studied. Special attention is devoted to the correlation between experimental spectra and the decay chains of 235 U and 238 U contained in the analyzed samples. The following applications are discussed: enrichment determination without using calibration standards, determination of uranium concentration, intensities of the gamma rays emitted by the nuclides present in the decay chains of study and the activity of such nuclides. Because of its importance, detailed discussion about the former one is shown. In addition, preliminary results regarding the emission probabilities of the most important gamma rays of 234m Pa are also informed. (author)

  10. Nuclear energy - Waste-packages activity measurement - Part.1: high-resolution gamma spectrometry in integral mode with open geometry

    International Nuclear Information System (INIS)

    2004-01-01

    ISO 14850:2004 describes a procedure for measurements of gamma-emitting radionuclide activity in homogeneous objects such as unconditioned waste (including process waste, dismantling waste, etc.), waste conditioned in various matrices (bitumen, hydraulic binder, thermosetting resins, etc.), notably in the form of 100 L, 200 L, 400 L or 800 L drums, and test specimens or samples, (vitrified waste), and waste packaged in a container, notably technological waste. It also specifies the calibration of the gamma spectrometry chain. The gamma energies used generally range from 0,05 MeV to 3 MeV. (authors)

  11. Homogenization of food samples for gamma spectrometry using tetramethylammonium hydroxide and enzymatic digestion

    International Nuclear Information System (INIS)

    Kimi Nishikawa; Abdul Bari; Abdul Jabbar Khan; Xin Li; Traci Menia; Semkow, T.M.

    2017-01-01

    We have developed a method of food sample preparation for gamma spectrometry involving the use of tetramethylammonium hydroxide (TMAH) and/or enzymes such as α-amylase or cellulase for sample homogenization. We demonstrated the effectiveness of this method using food matrices spiked with "6"0Co, "1"3"1I, "1"3"4","1"3"7Cs, and "2"4"1Am radionuclides, homogenized with TMAH (mixed salad, parmesan cheese, and ground beef); enzymes (α-amylase for bread, and cellulase for baked beans); or α-amylase followed by TMAH (cheeseburgers). Procedures were developed which are best compromises between the degree of homogenization, accuracy, speed, and minimizing laboratory equipment contamination. Based on calculated sample biases and z-scores, our results suggest that homogenization using TMAH and enzymes would be a useful method of sample preparation for gamma spectrometry samples during radiological emergencies. (author)

  12. Calibration of an air monitor prototype for a radiation surveillance network based on gamma spectrometry

    International Nuclear Information System (INIS)

    Baeza, A.; Caballero, J.M.; Corbacho, J.Á.; Ontalba-Salamanca, M.Á.; Vasco, J.

    2014-01-01

    The objective of this work is to present the improvements that have been made in quasi-real-time air radioactivity concentration monitors which were initially based on overall activity determinations, by incorporating gamma spectrometry into the current prototype. To this end it was necessary to develop a careful efficiency calibration procedure for both the particulate and the gaseous fractions of the air being sampled. The work also reports the values of the minimum detectable activity calculated for different isotopes and acquisition times. - Highlights: • Deficiencies of a commercial air monitoring system are detailed. • Gamma spectrometry introduction is the basis of the new prototype. • Efficiency calibration procedure is described for aerosol and gaseous fractions. • MDA is evaluated for different isotopes and acquisition times

  13. Significance of radioelement concentration measurements made by airborne gamma-ray spectrometry over the Canadian Shield

    International Nuclear Information System (INIS)

    Charbonneau, B.W.; Killeen, P.G.; Carson, J.M.; Cameron, G.W.; Richardson, K.A.

    1976-01-01

    Results of airborne gamma-ray spectrometer surveys conducted by the Geological Survey of Canada are presented as maps contoured in units of radioelement and concentration ratios. These contoured values represent the average surface concentrations of the radioelements over areas of the order of several square kilometres. The relationship between this ''average surface concentration'' and the radioelement concentration in bedrock underlying the area depends on: (1) the percentage of outcrop; (2) the relation between overburden and bedrock radioelement concentration; (3) percentage of marshland or surface water in the area; (4) soil moisture; and (5) density of vegetation. More than 2500 portable gamma-ray spectrometer analyses of outcrop and overburden have been made in the Bancroft, Elliot Lake and Fort Smith areas of the Canadian Precambrian Shield. In the areas examined, the radioelement concentrations in glacial drift reflect the concentrations in the underlying bedrock. Rocks with near-crustal average contents of thorium, uranium and potassium are overlain by glacial drift having approximately the same concentrations. As the concentration in bedrock increases, the concentration in the local overburden also increases, but not to the same extent. In addition, in-situ gamma-ray spectrometry measurements were made at almost 1000 stations within the area of airborne surveys near Mont Laurier and Elliot Lake. These ground measurements were compared with the airborne measurements by averaging the values for all those ground stations located in the areas between each contour level on airborne maps. Radioelement concentrations in bedrock are considerably higher than corresponding airborne measurements, and this difference between bedrock and airborne values increases at higher radioelement concentrations. Radioelement concentrations in glacial drift are only slightly higher than airborne contour values for the same area. Airborne contour maps of the radioelement ratios

  14. Study of different filtering techniques applied to spectra from airborne gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelm, Emilien; Gutierrez, Sebastien; Reboli, Anne; Menard, Stephanie; Nourreddine, Abdel-Mjid [Commissariat a l' Energie Atomique et aux energies alternatives - CEA, DAM, DIF F-91297 Arpajon (France); Arbor, Nicolas [Institut Pluridisciplinaire Hubert Curien, UMR 7178 Universite de Strasbourg-CNRS, 23 rue du Loess, BP 28, F-67037 Strasbourg Cedex 2 (France)

    2015-07-01

    One of the features of spectra obtained by airborne gamma spectrometry is low counting statistics due to the short acquisition time (1 s) and the large source-detector distance (40 m). It leads to considerable uncertainty in radionuclide identification and determination of their respective activities from the windows method recommended by the IAEA, especially for low-level radioactivity. The present work compares the results obtained with filters in terms of errors of the filtered spectra with the window method and over the whole gamma energy range. The results are used to determine which filtering technique is the most suitable in combination with some method for total stripping of the spectrum. (authors)

  15. Remarks on the gamma-ray spectrometry for the determination of natural radioisotopes

    International Nuclear Information System (INIS)

    Kalita, S.; Niewodniczanski, J.

    1987-01-01

    Semiconductor low-energy gamma ray spectrometry is compared with the routinely used scintillation method (within higher energy range). Measurements of low-energy natural gamma radiation using a semiconductor detector permit the determination of radioactive equilibrium of the uranium series. In this method 238 U ( 234 Th) content is determined by 63 keV, 226 Ra by 186 keV and 214 Pb by 295 keV gamma rays. Using the same results one can calculate a radioactive equilibrium coefficient R, defined as concentration ratio 226 Ra/ 238 U and a 222 Rn emanation ratio E, defined as 1 - 214 Pb/ 226 Ra (concentrations in uranium equivalent units). The relative standard errors for the method are: 10 - 15% in case of radioisotope content and about 18% for R and E determination. 7 refs., 2 figs., 2 tabs. (author)

  16. Implementation and application of the gaussian decomposition software for NaI gamma-ray spectrometry data

    International Nuclear Information System (INIS)

    Zeng Lihui; Wang Nanping Tian Gui

    2011-01-01

    In order to extract the information of peaks in different energy from the data of overlapping peaks in environmental gamma spectrometer, a spectrum data Gaussian decomposition soft is designed based on least- square Gaussian fitting method. The interface of this software is friendly, it can complete the decomposition of overlapping peaks in gamma spectrometer quickly by the way of man-machines interactive. The result that applied gamma spectrometry to data analysis in the field measurement indicates that the Gaussian decomposition soft can efficiently extract 137 Cs from overlapping peaks which has significance to assess the human nuclide contamination of environment. (authors)

  17. Spectrum-to-dose conversion operator value function of a Ge(Li) in-situ environmental gamma-ray spectrometer

    International Nuclear Information System (INIS)

    Terada, Hiromi; Sakai, Eiji; Katagiri, Masaki

    1976-05-01

    A spectrum-to-dose conversion operator value function was obtained for a 73cm 3 closed-end coaxial Ge(Li) in-situ environmental gamma-ray spectrometer; factors influencing the function are considered. (auth.)

  18. Physiologically active hydrogel (in situ gel of sparfloxacin and its evaluation for ocular retention using gamma scintigraphy

    Directory of Open Access Journals (Sweden)

    Himanshu Gupta

    2015-01-01

    Full Text Available Objective: Due to the structure and physiological barrier of eye, only 1% of instilled dose is available for action on the corneal surface. In this work, we developed and evaluated chitosan (pH sensitive and gellan gum (ion sensitive in situ gel of sparfloxacin to improve precorneal residence time. Materials and Methods: A protocol for radiolabeling of sparfloxacin with Tc-99m was optimized to study the ocular retention using gamma scintigraphy technique. Results: The clear formulation was developed. In vitro release showed a sustained and prolonged release compared to plain eye drop solution. Dynamic and static gamma scintigraphy showed better retention than plain eye drops. The ocular tolerance test (hen′s egg test-chorioallantoic membrane test and infra-red study showed that the formulation is nonirritant and can be used as ocular vehicle. Conclusion: Radiolabel protocol for sparfloxacin was successfully developed and evaluated on ocular retention studies of developed in situ gel. The developed in situ gel is non irritant and can go further with clinical evaluation.

  19. Airborne gamma-ray spectrometry data processing using 1.5D inversion.

    Science.gov (United States)

    Druker, Eugene

    2017-10-01

    Standard processing of Airborne Gamma-Ray Spectrometry data generally gives good results when the measurement conditions are almost constant within several footprint area sizes, with the possible exception of flight height variations in a small range. In practice, deviations, such as large or abrupt changes of flight height and/or rugged terrain are not so rare and lead to certain problems. This article proposes a different approach where the solutions of inverse problems are used for data processing. The approach is quite natural in the processing of field data measured along the flight lines: it explicitly takes into account 1.5D survey models and flight parameters - from topography to sources distribution on the surface. Also, it clearly demonstrates that the inverse problem of the Airborne Gamma-Ray Spectrometry does not have a unique solution. This feature can be used in accordance with the underlying geological problem since various formulations of inverse problems can lead to various geological solutions. The use of the approach is illustrated by several examples given for flight lines and survey areas. This approach can be particularly useful in situations where geological, geophysical and/or geographic survey conditions are far from the standard assumptions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Optimization of measurement geometries used by the C.I.R. 'Gamma Spectrometry' working group

    International Nuclear Information System (INIS)

    Escarieux, M.

    1979-01-01

    The choice of measurement geometry is closely tied to the objective sought in gamma quantitative analysis which consists in identifying the radionuclides present in a sample and in determining the voluminal quantities. The too low efficiency of the detector and the levels of activity sought make it necessary to place the sample in contact with the casing of the detector and select a sample geometry suited to the measurement. In point of fact this choice is often determined by other criteria, availability of the container for example, and this leads the laboratories taking part in the 'Gamma Spectrometry' Working Group of the Comite d'Instrumentation de Radioprotection to adopt joint gamma measurement geometries [fr

  1. Uranium Enrichment Determination of the InSTEC Sub Critical Ensemble Fuel by Gamma Spectrometry

    International Nuclear Information System (INIS)

    Borrell Munnoz, Jose L.; LopezPino, Neivy; Diaz Rizo, Oscar; D'Alessandro Rodriguez, Katia; Padilla Cabal, Fatima; Arbelo Penna, Yunieski; Garcia Rios, Aczel R.; Quintas Munn, Ernesto L.; Casanova Diaz, Amaya O.

    2009-01-01

    Low background gamma spectrometry was applied to analyze the uranium enrichment of the nuclear fuel used in the InSTEC Sub Critical ensemble. The enrichment was calculated by two variants: an absolute method using the Monte Carlo method to simulated detector volumetric efficiency, and an iterative procedure without using standard sources. The results confirm that the nuclear fuel of the ensemble is natural uranium without any additional degree of enrichment. (author)

  2. Identification of. gamma. -irradiated spices by electron spin resonance (ESR) spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Uchiyama, Sadao; Kawamura, Yoko; Saito, Yukio (National Inst. of Hygienic Sciences, Tokyo (Japan))

    1990-12-01

    The electron spin resonance (ESR) spectrometry spectra of white (WP), black (BP) and red (Capsicum annuum L. var. frutescerns L., RP) peppers each had a principal signal with a g-value of 2.0043, and the intensities of the principal signals were increased not only by {gamma}-irradiation but also by heating. Irradiated RP also showed a minor signal -30G from the principal one, and the intensity of the minor signal increased linearly with increasing dose from 10 to 50 kGy. Since the minor signal was observed in RP irradiated at 10 kGy and stored for one year, but did not appear either after heating or after exposure to this signal is unique to {gamma}-irradiated RP and should therefore be useful for the identification of {gamma}-irradiated spices of Capsicum genus, such as paprika and chili pepper. The computer simulation of the ESR spectra suggested that the minor signal should be assigned to methyl radical and the principal signal mainly to a combination of phenoxyl and peroxyl radicals. Such minor signals were found in {gamma}-irradiated allspice and cinnamon among 10 kinds of other spices. (author).

  3. Smoothing technology of gamma-ray spectrometry data based on matched filtering

    International Nuclear Information System (INIS)

    Gu Min; Ge Liangquan

    2009-01-01

    Traditional method of smoothness of gamma-ray spectrometry data gives rise to aberration of spectra curves easily. The article improve convolution sliding transformation using idea of matched filtering. Gauss adding the exponential function instead of Gauss function is used as converting function. The improved method not only suppresses statistical fluctuation mostly but also keeps feature of spectra curves. Instance verified superiority of this new method. (authors)

  4. Results from an interlaboratory exercise on the determination of plutonium isotopic ratios by gamma spectrometry

    International Nuclear Information System (INIS)

    Ottmar, H.

    1981-07-01

    Results form interlaboratory comparison measurements on the determination of plutonium isotopic ratios by gamma spectrometry, organized by the ESARDA Working Group on Techniques and Standards for Nondestructive Analysis, are presented and discussed. Nine laboratories from nine countries or international organizations participated in the intercomparison exercise, which included both laboratories' own measurements on the plutonium isotopic reference materials NBS-SRM 946, 947, 948 and comparison analyses of gamma spectra from these materials distributed to the participating laboratories. Results from the intercomparison analyses have been used to reevaluate some gamma branching intensity ratios required for plutonium isotopic ratio measurements. (orig.) [de

  5. Sodium fast reactor power monitoring using gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Coulon, R.; Normand, S.; Barbot, L.; Domenech, T.; Kondrasovs, V.; Corre, G.; Frelin, A.M. [CEA, LIST, Laboratoire Capteurs et Architectures Electroniques, CEA - Saclay DRT/LIST/DETECS/SSTM, Batiment 516 - P.C. no 72, Gif sur Yvette, F-91191 (France); Montagu, T.; Dautremer, T.; Barat, E. [CEA, LIST, Laboratoire Processus Stochastiques et Spectres (France); Ban, G. [ENSICAEN (France)

    2009-06-15

    This work deals with the use of high flux gamma spectrometry to monitor the fourth generation of sodium fast reactor (SFR) power. The simulation study part of this work has shown that power monitoring in a short time response and with a good accuracy is possible. An experimental test is under preparation at the French SFR Phenix experimental reactor to validate simulation studies. First, physical calculations have been done to correlate gamma activity to the released thermal power. Gamma emitter production rate in the reactor core was calculated with technical and nuclear data as the sodium velocity, the atomic densities, Phenix neutron spectrum and incident neutron cross-sections of reactions producing gamma emitters. A thermal hydraulic transfer function was used for modeling primary sodium flow in our calculations. For the power monitoring problematic, use of a short decay period gamma emitter will allow to have a very fast response system without cumulative effect. We have determined that the best tagging agent is 20F which emits 1634 keV energy photons with a decay period of 11 s. The gamma spectrum was determined by flux point and a pulse high tally MCNP5.1.40 simulation and shown the possibility to measure the signal of this radionuclide. The experiment will be set during the reactor 'end life testing'. The Delayed Neutron Detection (DND) room has been chosen as the best available location on Phenix reactor to measure this kind of radionuclide due to a short transit time from reactor core to measurement sample. This location is optimum for global power measurement because homogenized sampling in the reactor hot pool. The main spectrometer is composed of a coaxial high purity germanium diode (HPGe) coupled with a transistor reset preamplifier. The HPGe diode signal will be processed by the Adonis digital signal processing due to high flux and fast activity measurement. Post-processing softwares will be used to limit statistical problems of the

  6. Application of simulated standard spectra in natural radioactivity measurements using gamma spectrometry

    International Nuclear Information System (INIS)

    Narayani, K.; Pant, A.D.; Bhosle, Nitin; Anilkumar, S.; Singh, Rajvir; Pradeepkumar, K.S.

    2014-01-01

    Gamma ray spectrometry is one of the well known analytical techniques for environmental radioactivity measurements. Gamma spectrometer based on NaI(Tl) scintillation detectors is very popular since it offers high efficiency, low cost and case in handling. The poor energy resolution of the NaI(TI) detector is the major disadvantage making tile analysis of complex gamma ray spectra difficult. Least square method or the full spectrum analysis method is widely used for the analysis of complex spectra from scintillation detectors. The main requirement of this method is that the individual standard spectra of all nuclides expected in the complex spectrum in the same measurement geometry must be available. It is not always possible and feasible to have all the standards of nuclides in the desired geometry. A methodology based on the use of simulated standard spectra generated by Monte Carlo technique was proposed for analysis of complex spectra of nuclides. In the present work, for the analysis of 238 U, 233 Th and 40 K in soil samples, the same methodology was applied by using the simulated standard spectra in soil matrix. The details of the simulation method and results analysis of 238 U, 232 Th and 40 K in environmental samples are discussed in this paper

  7. The use of gamma spectrometry in mapping alteration zones in Olkiluoto

    International Nuclear Information System (INIS)

    Ojala, J.V.; Turunen, P.; Eilu, P.; Julkunen, A.; Gehoer, S.

    2007-08-01

    In the Olkiluoto site, a detailed gammaspectrometry log from the drill hole OL-KR27 was used to estimate the concentrations of K, Th and U. The gamma spectrometry results, lithological variations, and kaolinite and illite alteration visually mapped from the drill hole were compared. The result indicate that the Th/K ratio correlates best with lithology and that, in most cases, the changes in the ratio indicate lithological contacts and rising or falling trends of Th/K ratio with some peaks have some correlation with the kaolinite-illite alteration. From the result it is suggested that that very variable Th/K ratio is a reasonably good indicator of alteration zones even in the migmatic gneiss area in the Olkiluoto site. (orig.)

  8. Measurement of natural gamma radiation in building materials from Thellar of Tiruvannamalai Dist, Tamilnadu, India by gamma ray spectrometry

    International Nuclear Information System (INIS)

    Raghu, Y.; Ravisankar, R.; Chandrasekararn, A.; Vijayagopal, P.; Venkatraman, B.

    2016-01-01

    The knowledge of natural radioactivity in building materials is an important aspect of or determining the amount of public exposure because people spend most of their time (about 80%) indoors. Further, the knowledge of this radioactivity is useful in setting the standards and national guidelines in regard to the international recommendations and in assessing the associated radiation hazard. In the present work, the concentrations of natural radionuclides were measured in four types of building materials from Thellar of Tiruvannamalai district, Tamilnadu, India using gamma-ray spectrometry and associated radiological hazards are calculated

  9. Assessment of calibration parameters for an aerial gamma spectrometry system using Monte-Carlo technique

    International Nuclear Information System (INIS)

    Srinivasan, P.; Raman, Anand; Sharma, D.N.

    2009-01-01

    Aerial gamma spectrometry is a very effective method for quickly surveying a large area, which might get contaminated following a nuclear accident, or due to nuclear weapon fallout. The technique not only helps in identifying the contaminating radionuclide but also in assessing the magnitude and the extent of contamination. These two factors are of importance for the authorities to quickly plan and execute effective counter measures and controls if required. The development of Airborne gamma ray spectrometry systems have been reported by different institutions. The application of these systems have been reported by different authors. Radiation Safety Systems Division of the Bhabha Atomic Research Centre has developed an Aerial Gamma Spectrometry System (AGSS) and the surveying methodology. For an online assessment of the contamination levels, it is essential to calibrate the system (AGSS) either flying it over a known contaminated area or over a simulated contaminated surface by deploying sealed sources on the ground. AGSS has been calibrated for different detectors in aerial exercises using such simulated contamination on the ground. The calibration methodology essentially needs net photo-peak counts in selected energy windows to finally arrive at the Air to Ground Correlation Factors at selected flight parameters such as altitude, speed of flight and the time interval at which each spectrum is acquired. This paper describes the methodology to predict all the necessary parameters like photon fluence at various altitudes, the photo-peak counts in different energy windows, Air to Ground Correlation Factors(AGCF), the dose rate at any height due to air scattered gamma ray photons etc. These parameters are predicted for a given source deployment matrix, detector and altitude of flying using the Monte-Carlo code MCNP (Monte Carlo Neutron and Photon Transport Code.CCC-200, RSIC, ORNL, Tennessee, USA). A methodology to generate the completely folded gamma ray count

  10. Using airborne GAMMA-ray spectrometry (uranium, thorium, potassium) to quantify weathering and erosion processes

    International Nuclear Information System (INIS)

    Carrier, F.

    2005-01-01

    The airborne gamma-ray spectrometry survey carried out on the Armorican Massif provided soil contents in U, Th and K in ppm. Chemical and mechanical erosion processes within a homogeneous geological unit have been estimated using their variations and those of the 137 Cs. Our new approach, based on a multivariate analysis (hierarchic ascending classification), integrates the airborne gamma-ray spectrometry data, with their broad spatial distribution, together with precisely located station data (major elements, traces and isotopic geochemistry) resulting from a soil and river water erosion products survey. The total export of potassium was estimated in any point of an area catchment (50-m resolution) until 17+2 t/km 2 /a for a 50-m thick weathering profile. Erosion study by river sampling provide important biases, for the perennial river does not integrate the whole range of erosion products: the geochemical signature of the valleys is currently more represented than plateau areas. (author)

  11. Preconcentration of natural protactinium from thorium concentrate with subsequent determination using Gamma (γ) spectrometry

    International Nuclear Information System (INIS)

    Raja, Naine; Swain, Kallola; Kayasth, S.R.; Pathassarathy, R.; Mathur, P.K.; Anil Kumar, S.

    1999-01-01

    A simple and efficient method has been developed to preconcentrate natural protactinium ( 231 Pa) from large size of thorium concentrate (5.0-100.0g) on Dowex 1 X 8 in acid medium. Gamma spectrometry, a powerful determination technique, has been used for quantitative determination of protactinium

  12. A simple gamma spectrometry method for evaluating the burnup of MTR-type HEU fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Makmal, T. [The Unit of Nuclear Engineering, Ben-Gurion University of The Negev, Beer-Sheva 84105 (Israel); Nuclear Physics and Engineering Division, Soreq Nuclear Research Center, Yavne 81800 (Israel); Aviv, O. [Radiation Safety Division, Soreq Nuclear Research Center, Yavne 81800 (Israel); Gilad, E., E-mail: gilade@bgu.ac.il [The Unit of Nuclear Engineering, Ben-Gurion University of The Negev, Beer-Sheva 84105 (Israel)

    2016-10-21

    A simple method for the evaluation of the burnup of a materials testing reactor (MTR) fuel element by gamma spectrometry is presented. The method was applied to a highly enriched uranium MTR nuclear fuel element that was irradiated in a 5 MW pool-type research reactor for a total period of 34 years. The experimental approach is based on in-situ measurements of the MTR fuel element in the reactor pool by a portable high-purity germanium detector located in a gamma cell. To corroborate the method, analytical calculations (based on the irradiation history of the fuel element) and computer simulations using a dedicated fuel cycle burnup code ORIGEN2 were performed. The burnup of the MTR fuel element was found to be 52.4±8.8%, which is in good agreement with the analytical calculations and the computer simulations. The method presented here is suitable for research reactors with either a regular or an irregular irradiation regime and for reactors with limited infrastructure and/or resources. In addition, its simplicity and the enhanced safety it confers may render this method suitable for IAEA inspectors in fuel element burnup assessments during on-site inspections. - Highlights: • Simple, inexpensive, safe and flexible experimental setup that can be quickly deployed. • Experimental results are thoroughly corroborated against ORIGEN2 burnup code. • Experimental uncertainty of 9% and 5% deviation between measurements and simulations. • Very high burnup MTR fuel element is examined, with 60% depletion of {sup 235}U. • Impact of highly irregular irradiation regime on burnup evaluation is studied.

  13. Mass determination of U-233 and Pu-239 by gamma spectrometry technique

    International Nuclear Information System (INIS)

    Moraes, M.A.P.V. de; Pugliesi, R.

    1988-09-01

    The gamma spectrometry technique has been used for masses determinations of uranium-233 and plutonium-239, granted by AERE-HARWELL. A high purity Ge semicondutor detector was used and the total efficiency curve was obtained for the counting system in the energy range 13 KeV to 135 KeV. The calculated values for the masses compared with that obtained by means of gravimetry technique. (author) [pt

  14. Final results of the PIDIE intercomparison exercise for the plutonium isotopic determination by gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Morel, J.; Chauvenet, B.; Etcheverry, M.

    1991-01-01

    Final results from the PIDIE intercomparison exercise organised by the ESARDA Working Group on techniques and standards for non-destructive analysis are presented. The aim of this exercise carried out in 1988 was to test the gamma-ray spectroscopy methods used to determine the plutonium isotopic ratios in a large range of isotopic composition, in order to analyse the parameters and the error sources influencing the results. Sets of seven sealed samples of different plutonium isotopic composition were sent to nine participating laboratories. The final results with uncertainty indicators are reported; they are compared with complementary mass-spectrometry determinations. No important bias has been observed from this exercise. Significant improvements in plutonium isotopic determination by gamma-ray spectrometry come from both more elaborate spectrum analysis methods and better equipment

  15. Results of the 1988 interlaboratory comparison on the gamma spectrometry of dried whey

    International Nuclear Information System (INIS)

    Wiechen, A.; Tait, D.; Bundesanstalt fuer Milchforschung, Kiel

    1988-01-01

    Following the accident in Chernobyl in 1986 the number of units available for monitoring radioactivity, mainly gamma spectrometers, has been increased considerably in the Federal Republic of Germany. Furthermore, new legislation requires that all official monitoring laboratories verify the quality of their analytical technique by participating in interlaboratory comparison studies organized by Federal institutions. Such a study was therefore organized in March 1988. 86 laboratories collaborated on the gamma-spectrometry analysis of the radionuclides Cs-137, Cs-134 and K-40 in dried whey. This paper describes the statistical evaluation of the 144 sets of data received. The results of the study were surprisingly good. (orig./DG) [de

  16. Standard test method for quantitative determination of americium 241 in plutonium by Gamma-Ray spectrometry

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1994-01-01

    1.1 This test method covers the quantitative determination of americium 241 by gamma-ray spectrometry in plutonium nitrate solution samples that do not contain significant amounts of radioactive fission products or other high specific activity gamma-ray emitters. 1.2 This test method can be used to determine the americium 241 in samples of plutonium metal, oxide and other solid forms, when the solid is appropriately sampled and dissolved. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  17. Assessing sample attenuation parameters for use in low-energy efficiency transfer in gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Bruggeman, M.; Verheyen, L.; Vidmar, T.; Liu, B.

    2016-01-01

    We present a numerical fitting method for transmission data that outputs an equivalent sample composition. This output is used as input to a generalised efficiency transfer model based on the EFFTRAN software integrated in a LIMS. The procedural concept allows choosing between efficiency transfer with a predefined sample composition or with an experimentally determined composition based on a transmission measurement. The method can be used for simultaneous quantification of low-energy gamma emitters like "2"1"0Pb, "2"4"1Am, "2"3"4Th in typical environmental samples. - Highlights: • New fitting method for experimentally determined attenuation coefficients. • Generalised efficiency transfer with EFFTRAN based on transmission measurements. • Method of generalized efficiency transfer integrated in LIMS. • Method applicable to gamma-ray spectrometry of environmental samples.

  18. A Comparison between HPGe and NaI(Tl) detectors performance for gamma-spectrometry of low level measurement

    International Nuclear Information System (INIS)

    Poursiamy, N. H.; Tajikahmadi, H.; Mirshojaei, S. F.

    2005-01-01

    According to progressive usage of nuclear technology, it's important to prevent the contamination of the environment by man-made radioisotopes and exposures of human being. Radioisotopes can enter the human body by inhalation and ingestion which are the most important ways to internal exposures. Measurement of radiation level in foodstuff is one of the most important parameters in environmental safety which is performed according to constitution and standard tests in most countries such as Iran. Gamma spectrometry is carried out by NaI(Tl) and HPGe detector systems for foodstuffs. In this research operation of HPGe and NaI(Tl) detectors in gamma spectrometry with a standard radioactive source are investigated and compared. Also the result of NaI superiority in foodstuff radiation measurement given

  19. Specialized software utilities for gamma ray spectrometry. Final report of a co-ordinated research project 1996-2000

    International Nuclear Information System (INIS)

    2002-03-01

    A Co-ordinated Research Project (CRP) on Software Utilities for Gamma Ray Spectrometry was initiated by the International Atomic Energy Agency in 1996 for a three year period. In the CRP several basic applications of nuclear data handling were assayed which also dealt with the development of PC computer codes for various spectrometric purposes. The CRP produced several software packages: for the analysis of low level NaI spectra; user controlled analysis of gamma ray spectra from HPGe detectors; a set of routines for the definition of the detector resolution function and for the unfolding of experimental annihilation spectra; a program for the generation of gamma ray libraries for specific applications; a program to calculate true coincidence corrections; a program to calculate full-energy peak efficiency calibration curve for homogenous cylindrical sample geometries including self-attenuation correction; and a program for the library driven analysis of gamma ray spectra and for the quantification of radionuclide content in samples. In addition, the CRP addressed problems of the analysis of naturally occurring radioactive soil material gamma ray spectra, questions of quality assurance and quality control in gamma ray spectrometry, and verification of the expert system SHAMAN for the analysis of air filter spectra obtained within the framework of the Comprehensive Nuclear Test Ban Treaty. This TECDOC contains 10 presentations delivered at the meeting with the description of the software developed. Each of the papers has been indexed separately

  20. Cosmic veto gamma-spectrometry for Comprehensive Nuclear-Test-Ban Treaty samples

    International Nuclear Information System (INIS)

    Burnett, J.L.; Davies, A.V.

    2014-01-01

    The Comprehensive Nuclear-Test-Ban Treaty (CTBT) is supported by a global network of monitoring stations that perform high-resolution gamma-spectrometry on air filter samples for the identification of 85 radionuclides. At the UK CTBT Radionuclide Laboratory (GBL15), a novel cosmic veto gamma-spectrometer has been developed to improve the sensitivity of station measurements, providing a mean background reduction of 80.8% with mean MDA improvements of 45.6%. The CTBT laboratory requirement for a 140 Ba MDA is achievable after 1.5 days counting compared to 5–7 days using conventional systems. The system consists of plastic scintillation plates that detect coincident cosmic-ray interactions within an HPGe gamma-spectrometer using the Canberra Lynx TM multi-channel analyser. The detector is remotely configurable using a TCP/IP interface and requires no dedicated coincidence electronics. It would be especially useful in preventing false-positives at remote station locations (e.g. Halley, Antarctica) where sample transfer to certified laboratories is logistically difficult. The improved sensitivity has been demonstrated for a CTBT air filter sample collected after the Fukushima incident

  1. Cosmic veto gamma-spectrometry for Comprehensive Nuclear-Test-Ban Treaty samples

    Science.gov (United States)

    Burnett, J. L.; Davies, A. V.

    2014-05-01

    The Comprehensive Nuclear-Test-Ban Treaty (CTBT) is supported by a global network of monitoring stations that perform high-resolution gamma-spectrometry on air filter samples for the identification of 85 radionuclides. At the UK CTBT Radionuclide Laboratory (GBL15), a novel cosmic veto gamma-spectrometer has been developed to improve the sensitivity of station measurements, providing a mean background reduction of 80.8% with mean MDA improvements of 45.6%. The CTBT laboratory requirement for a 140Ba MDA is achievable after 1.5 days counting compared to 5-7 days using conventional systems. The system consists of plastic scintillation plates that detect coincident cosmic-ray interactions within an HPGe gamma-spectrometer using the Canberra LynxTM multi-channel analyser. The detector is remotely configurable using a TCP/IP interface and requires no dedicated coincidence electronics. It would be especially useful in preventing false-positives at remote station locations (e.g. Halley, Antarctica) where sample transfer to certified laboratories is logistically difficult. The improved sensitivity has been demonstrated for a CTBT air filter sample collected after the Fukushima incident.

  2. Cosmic veto gamma-spectrometry for Comprehensive Nuclear-Test-Ban Treaty samples

    Energy Technology Data Exchange (ETDEWEB)

    Burnett, J.L., E-mail: jonathan.burnett@awe.co.uk; Davies, A.V.

    2014-05-21

    The Comprehensive Nuclear-Test-Ban Treaty (CTBT) is supported by a global network of monitoring stations that perform high-resolution gamma-spectrometry on air filter samples for the identification of 85 radionuclides. At the UK CTBT Radionuclide Laboratory (GBL15), a novel cosmic veto gamma-spectrometer has been developed to improve the sensitivity of station measurements, providing a mean background reduction of 80.8% with mean MDA improvements of 45.6%. The CTBT laboratory requirement for a {sup 140}Ba MDA is achievable after 1.5 days counting compared to 5–7 days using conventional systems. The system consists of plastic scintillation plates that detect coincident cosmic-ray interactions within an HPGe gamma-spectrometer using the Canberra Lynx{sup TM} multi-channel analyser. The detector is remotely configurable using a TCP/IP interface and requires no dedicated coincidence electronics. It would be especially useful in preventing false-positives at remote station locations (e.g. Halley, Antarctica) where sample transfer to certified laboratories is logistically difficult. The improved sensitivity has been demonstrated for a CTBT air filter sample collected after the Fukushima incident.

  3. Analysis of burnt nuclear fuel elements by gamma-spectrometry

    International Nuclear Information System (INIS)

    Lammer, M.

    1978-01-01

    Gamma-spectrometry allows a non-destructive determination of the fission and activation product content of spent nuclear fuel. The concentration of some of these products depends significantly on the so-called fuel parameters which describe the irradiation history and the fuel composition. The use of these dependences for deriving ''unknown fuel parameters'' from measured fission product activities is investigated in this work. Relevant application fields are burnup determination, fuel testing and inspections within the nuclear materials safeguards programme. The present thesis investigates how these dependences can be used to derive unknown fuel parameters. The possibilities and basic limitations of deriving information from a measured gamma spectrum are considered on principle. The main conclusion is that only ratios of fission product activities allow the development of an interpretation method which is generally applicable to all types of fuel from different reactors. The dependence of activity ratios on cooling time, irradiation time, integrated and final neutron flux, fuel composition, as well as fission and breeding rates are then investigated and presented graphically in a way suitable for applicaton. These relationships can be used for the analysis of spent fuel, and the detailed procedures, which depend on the applicaton field, are worked out in this work. In order to test the interpretation methods, samples of nuclear fuel have been irradiated and the gamma spectra analysed. The methods developed in this work can be applied successfully to the analysis of burnt fuel in the frame of fuel testing programmes and to safeguards verification purposes. If however, apart from a gamma spectrum, no information on the investigated fuel is available, the above-mentioned parameters can be derived with low accuracy only. (author)

  4. Burn-Up Determination by High Resolution Gamma Spectrometry: Fission Product Migration Studies

    Energy Technology Data Exchange (ETDEWEB)

    Forsyth, R S; Blackadder, W H; Ronqvist, N

    1967-04-15

    The migration of solid fission products, in particular caesium and ruthenium, in high temperature oxide fuel can create a severe problem during the application of non-destructive burn-up methods employing gamma spectrometry, since caesium-137 is otherwise the most convenient long-lived burn-up monitor and ruthenium-106 can be used to distinguish between fissions in U-235 and Pu-239. As part of an experimental programme to develop burn-up methods, gamma scanning experiments have been performed on slices of irradiated UO{sub 2} pellets using a lithium-drifted germanium detector. The usefulness of the technique for migration studies has been demonstrated by comparing the fission product distribution curves across the specimen diameters with the microstructure of the specimens after polishing and etching.

  5. Uranium series radioactive disequilibria study using gamma spectrometry with low energy and application to the dating in geology

    International Nuclear Information System (INIS)

    Khoukhi, T. El.

    1992-01-01

    In this work, the gamma spectrometry with low energy has been used with the help of Ge high purity planar detector, and the means and limits of this spectrometry in the applications to the dating in geology has been studied. A geological sample taken from the moroccan phosphatic deposit of Gantour, having a secondary mineralization wealth of uranium has principally been studied in application. In addition, physical models of uranium genesis have been elaborated in the course of this work in order to interpret the achieved results. 60 figs., 18 tabs., 53 refs. (F.M.)

  6. Natural gamma-ray spectrometry as a tool for radiation dose and radon hazard modelling

    International Nuclear Information System (INIS)

    Verdoya, M.; Chiozzi, P.; De Felice, P.; Pasquale, V.; Bochiolo, M.; Genovesi, I.

    2009-01-01

    We reviewed the calibration procedures of gamma-ray spectrometry with particular emphasis to factors that affect accuracy, detection limits and background radiation in field measurements for dosimetric and radon potential mapping. Gamma-ray spectra were acquired in western Liguria (Italy). The energy windows investigated are centred on the photopeaks of 214 Bi (1.76 MeV), 208 Tl (2.62 MeV) and 40 K (1.46 MeV). The inferred absorbed dose rate and the radon flux are estimated to be lower than 60 nGy h -1 and 22 Bq m -2 h -1 , respectively.

  7. Bibliographical study on the high-purity germanium radiation detectors used in gamma and X spectrometry

    International Nuclear Information System (INIS)

    Bornand, Bernard; Friant, Alain

    1979-03-01

    The germanium or silicon lithium-drifted detectors, Ge(Li) or Si(Li), and high-purity germanium detectors, HP Ge (impurity concentration approximately 10 10 cm -3 ), are the most commonly used at the present time as gamma and X-ray spectrometers. The HP Ge detectors for which room temperature storage is the main characteristic can be obtained with a large volume and a thin window, and are used as the Ge(Li) in γ ray spectrometry or the Si(Li) in X-ray spectrometry. This publication reviews issues from 1974 to 1978 on the state of the art and applications of the HP Ge semiconductor detectors. 101 bibliographical notices with French summaries are presented. An index for authors, documents and periodicals, and subjects is included [fr

  8. The participation of ATOMKI in the G-2 international intercomparison of high precision gamma-ray spectrometry measurements

    International Nuclear Information System (INIS)

    Gaspar, A.; Lakatos, T.; Sulik, B.; Toeroek, I.

    1981-01-01

    International intercomparison had been organized by the IAEA in high precision gamma spectrometry. Five mixed-spectrum sources were prepared and sent to the participants by the IAEA for relative gamma emission rate measurements. This source type enables the whole measuring method and procedure to be tested. Measurements were carried out using two independent methods: a.) simple normalization to an additional radioactive source; b.) using a time variant pulse processor and random pulse generator for correction of dead-time and pile-up losses. The results agreed in most cases within +-1% with the IAEA results. (R.J.)

  9. Application of neutron-induced gamma ray spectrometry for in situ assessment of coal quality

    International Nuclear Information System (INIS)

    Chrusciel, E.; Leutsoa Makhabane, J.

    1990-01-01

    The physical principles of the spectrometric neutron capture borehole logging method and spectrometric neutron activation borehole logging method are presented. Nuclear parameters of major elemental constituents of coal are given. Statistical multiple correlation results of coal core samples assessment are presented for coal quality parameters. The results of in situ spectrometric measurements in a coal field are also given. 7 figs., 11 tabs., 15 refs. (author)

  10. Research on digital airborne gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Ge Liangquan; Lai Wanchang; Zeng Guoqiang; Fan Zhenguo; Xiong Shengqing; Ni Weizhong

    2010-01-01

    Airborne Gamma-ray Spectrometry (AGS) is a main supporting technique for looking for uranium deposits and other non-radioactive mineral deposit, as well as for investigating environmental radiation pollution and monitoring nuclear equipment. This paper describes the newest achievements about the AGS instrument developed by Chengdu university of Technology. Those are: 1) the probe of AGS is composed of 5 NaI(Tl) + PMT scintillation counters with 10 x 10 x 40 mm size, and a special temperature sensor, preamplifier with circuit negative feedback and high voltage with lower electronic noise have been designed. 2)A Y/U double channel digital controlled gain amplifier for adjusting the spectrum drift finely and high speed ADC and CPLD are designed to perform digitalized spectroscopy and to improve the energy resolution and pulse through output rate (more than 100k/s). 3) Two self-stabilization spectrum loops have been designed for spectrum stability: The first loop is roughly adjusted by temperature and the second loop is finely by Kalman filter. 4) The significant characters of new AGS system are: the detective gamma energy range is 0.02∼10.0 MeV, the spectrum drift is ±1 channel, the collecting period is 0.5-1 s, and 20 NaI(Tl)+PMT scintillation counters can be operated at the same time. (authors)

  11. Evaluation of TASTEX task H: measurement of plutonium isotopic abundances by gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Gunnink, R.; Prindle, A.L.; Asakura, Y.; Masui, J.; Ishiguro, N.; Kawasaki, A.; Kataoka, S.

    1981-10-01

    This report describes a computer-based gamma spectrometer system that was developed for measuring isotopic and total plutonium concentrations in nitric acid solutions. The system was installed at the Tokai reprocessing plant where it is undergoing testing and evaluation as part of the Tokai Advanced Safeguards Exercise (TASTEX). Objectives of TASTEX Task H, High-Resolution Gamma Spectrometer for Plutonium Isotopic Analysis, the methods and equipment used, the installation and calibration of the system, and the measurements obtained from several reprocessing campaigns are discussed and described. In general, we find that measurements for gamma spectroscopy agree well with those of mass spectrometry and of other chemical analysis. The system measures both freshly processed plutonium from the product accountability tank and aged plutonium solutions from storage tanks. 14 figures, 15 tables

  12. Determination of activity by gamma spectrometry of radionuclides present in drums of residues generated in nuclear centrals

    International Nuclear Information System (INIS)

    Aguiar, J.C.; Fernandez, J.

    2006-01-01

    The generation of radioactive residuals in nuclear centrals as CNA I (Atucha I Nuclear Central) and CNE (Embalse Nuclear Central) makes that the measurement of those radionuclides has been a previous stage to the waste management. A method used in those nuclear centrals it is the gamma spectrometry with HPGe detectors, previous to the immobilization of the residual in a cemented matrix, with this the contact with the external agents and its possible dispersion to the atmosphere in the short term is avoided. The ARN (Nuclear Regulatory Authority) of Argentina it carries out periodically intercomparisons and evaluations of the measurement and procedures systems used in the nuclear power stations for the correct measurement and determination of activity of radioactive residuals by gamma spectrometry. In this work an independent method of measurement is exposed to the nuclear power stations. To determine the activity of the residuals by gamma spectrometry deposited in drums, it is required of the precise knowledge of the efficiency curve for such geometry and matrix. Due to the RNA doesn't have a pattern of these characteristics, a mathematical model has been used to obtain this efficiency curve. For it, it is necessary to determine previously: 1) the geometric efficiency or solid angle sustained by the source-detector system (drum-detector) applying a mathematical model described in this work. 2) To estimate the auto-attenuation factor that present the photons in the cemented matrix, these calculations are carried out with a simple equation and its are verified with the Micro Shield 6.10 program. The container commonly used by these nuclear power stations its are drums for 220 liters constructed with SAE 1010 steel and with a thickness of 0.127 cm, with an approximate weight 7.73 Kg., internal diameter of 57.1 cm, and height: 87 cm. The results obtained until the moment register a discrepancy from 5 to 10% with relationship to the measurements carried out by the

  13. Evaluation of the natural radioactivity using thermoluminescence, gamma spectrometry and neutron activation techniques

    International Nuclear Information System (INIS)

    Fausto, A.M.; Otsubo, S.M.; Paes, W.S.; Yoshimura, E.M.; Okuno, E.; Hiodo, F.; Marques, L.S.; Alcala, A.L.

    1996-01-01

    The evaluation of the radiation dose in the living species due to the natural radioactivity is the main objective of this paper. The region that had been monitored was Intrusive Suite of Itu near to Sao Paulo city. Lateral[and depth distributions of natural radioactivity of the soil were determined using the techniques of thermoluminescence gamma spectrometry and neutron[activation. From the concentration in the soil of K-40 and radioactive elements of U and Th series experimentally determined, the dose due to gamma rays in air at 1 m from the soil was evaluated and the results compared with the direct dose measured with the portable rate-meter. (authors). 11 refs., 3 figs

  14. Nuclear energy. Waste-packages activity measurement. Part. 1: high-resolution gamma spectrometry in integral mode with open geometry; ISO 14850-1: 2004. Energie nucleaire -- Mesurage de l'activite de colis de dechets. Partie 1: Spectrometrie gamma haute resolution en mode integral et geometrie ouverte

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    ISO 14850:2004 describes a procedure for measurements of gamma-emitting radionuclide activity in homogeneous objects such as unconditioned waste (including process waste, dismantling waste, etc.), waste conditioned in various matrices (bitumen, hydraulic binder, thermosetting resins, etc.), notably in the form of 100 L, 200 L, 400 L or 800 L drums, and test specimens or samples, (vitrified waste), and waste packaged in a container, notably technological waste. It also specifies the calibration of the gamma spectrometry chain. The gamma energies used generally range from 0,05 MeV to 3 MeV.

  15. Nuclear energy - Waste-packages activity measurement - Part.1: high-resolution gamma spectrometry in integral mode with open geometry; ISO 14850-1:2004. Energie nucleaire - Mesurage de l'activite de colis de dechets - Partie 1: spectrometrie gamma haute resolution en mode integral et geometrie ouverte

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    ISO 14850:2004 describes a procedure for measurements of gamma-emitting radionuclide activity in homogeneous objects such as unconditioned waste (including process waste, dismantling waste, etc.), waste conditioned in various matrices (bitumen, hydraulic binder, thermosetting resins, etc.), notably in the form of 100 L, 200 L, 400 L or 800 L drums, and test specimens or samples, (vitrified waste), and waste packaged in a container, notably technological waste. It also specifies the calibration of the gamma spectrometry chain. The gamma energies used generally range from 0,05 MeV to 3 MeV. (authors)

  16. High-z semiconductor nuclear radiation detectors for room-temperature gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Bornand, Bernard; Friant, Alain.

    1978-09-01

    A bibliographical review (182 articles of periodicals, conferences, reports, thesis and french patents) is presented, as addendum of the report CEA-BIB-210 (1974) on high-Z semiconductor compounds used as materials for the gamma and X-ray detection and spectrometry. This publication reviews issues from 1974 to 1977. References and summaries (in french) are incorporated into 182 bibliograhical notices. Index for authors, corporate authors, documents and periodicals, and subjects is included [fr

  17. Multidimensional Gamma-Ray Spectrometry and its Use in Biology; La Spectrometry Gamma Multidimensionnelle et son Application en Biologie; Mnogomernaya spektrometriya gamma-luchej i ee ispol'zovanie v biologii; La Espectrometria Gamma Multidimensional y su Empleo en Biologia

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, J. M.; Kornberg, H. A. [Battelle Memorial Institute, Pacific Northwest Laboratory, Richland, WA (United States)

    1965-10-15

    Multidimensional gamma-ray spectrometry is a new technique for the measurement of radionuclides which has special application in biology. This instrumental technique allows direct identification and measurement of individual gamma-ray emitters in complex mixtures of radionuclides in diverse sample matrices without prior chemical treatment. The detector system is designed to provide: high sensitivity through use of two large (6-in diam., 4-in thick) Nal(Tl) detectors; high selectivity by using coincidence counting techniques which separate gamma ray spectra by taking advantage of the gamma-ray decay characteristics of each radionuclide ; and ultra-low background and reduced Compton interference through a surrounding anticoincidence annulus detector (a NaI(Tl) crystal 11 Vulgar-Fraction-One-Half -in thick with a 6 Vulgar-Fraction-One-Half - in - diam. hole). A 4096-channel multidimensional analyser analyses the two gamma-rays in coincidence according to their energies and stores them in the plane of the 64 X 64-channel memory while non-coincident events are stored only on the axes of the memory. This effectively decreases the background and Compton interference by orders of magnitude while greatly improving the selectivity. Direct gamma-ray spectrometric measurement of trace levels of radionuclides in biological samples has been inhibited by the presence of relatively large amounts of natural 4 Degree-Sign K whose 1.47 MeV gamma-radiation has interfered with their measurement. Since most radionuclides decay through emission of two or more gamma-rays in cascade the new technique does provide a direct selective measurement and permits wider application. For example, {sup 22}Na (a naturally occurring cosmic-ray produced radionuclide), {sup 134}Cs and {sup 137}Cs (fission products) can be readily measured at existing levels (in some cases at less than 1 dpmAg) in meat, fish, foodstuffs, as well as in urine, so that uptake-excretion studies are possible. This technique

  18. Volatiles emitted from flowers by gamma-radiated and nonradiated Jasminum polyanthum Franch. in situ

    International Nuclear Information System (INIS)

    Christensen, L.P.; Jakobsen, H.B.; Kristiansen, K.; Moller, J.

    1997-01-01

    Volatile compounds emitted from flowers of Jasminum polyanthum Pepita in situ were collected by dynamic headspace technique and analyzed by GC-FID and GC-MS. A total of 32 compounds were identified. The flower scent was dominated by benzyl acetate (57.8%), p-cresol (12.2%), (E)-isoeugenol (9.7%), eugenol (3.5%), 2-methoxy-p-cresol (3.1%), linalool (3.0%), phenethyl acetate (2.1%), and (Z)3-hexenyl butyrate (1.9%). The strong scent of Pepita reduces its production potentialities as a pot plant, thus the possibility to reduce or modify the emission of volatiles from Pepita by mutagenesis was investigated. The average total yields of volatiles in Pepita were approximately 2800 ng flower-1 h-1, and in one gamma-radiated clone a significantly lower yield of 1050 ng flower-1 h-1 was found. The volatile profiles of the gamma-radiated plants were made up of the same 32 compounds found in Pepita. Significant differences in the headspace composition between Pepita and gamma-radiated plants were found for some of the major volatiles

  19. Use of gamma spectrometry for studying fuel plates

    International Nuclear Information System (INIS)

    Carteret, Y.; Schley, R.; Simonet, G.

    1979-01-01

    The programme of experimental irradiation performed at the CEA on the CARAMEL plate fuel was followed by gamma spectrometry, jointly with other techniques. The qualitative study of the distribution of fission products constitutes a source of information on the behavior of the fuel (temperature and structure) and enables its utilization limits to be predicted. The quantitative determination of short and long half life fission products makes it possible to calculate the specific power and specific burn-up. Carried out periodically, it is a means of checking the values obtained by the continuous measurement of cladding temperature, directly linked to the specific burn-up. At the end of irradiation, the results are compared against those achieved by neodymium analysis. The study of the change in gadolinium, a burnable poison, is an application of this technique [fr

  20. The {sup 124}Sb activity standardization by gamma spectrometry for medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, M.C.M. de, E-mail: marcandida@yahoo.com.b [Laboratorio Nacional de Metrologia das Radiacoes Ionizantes, Instituto de Radioprotecao e Dosimetria, Comissao Nacional de Energia Nuclear (SEMRA/LNMRI/IRD/CNEN), Av. Salvador Allende s/n, Recreio, Rio de Janeiro, RJ, CEP 22780-160 (Brazil); Iwahara, A.; Delgado, J.U.; Poledna, R.; Silva, R.L. da [Laboratorio Nacional de Metrologia das Radiacoes Ionizantes, Instituto de Radioprotecao e Dosimetria, Comissao Nacional de Energia Nuclear (SEMRA/LNMRI/IRD/CNEN), Av. Salvador Allende s/n, Recreio, Rio de Janeiro, RJ, CEP 22780-160 (Brazil)

    2010-07-21

    This work describes a metrological activity determination of {sup 124}Sb, which can be used as radiotracer, applying gamma spectrometry methods with hyper pure germanium detector and efficiency curves. This isotope with good activity and high radionuclidic purity is employed in the form of meglumine antimoniate (Glucantime) or sodium stibogluconate (Pentostam) to treat leishmaniasis. {sup 124}Sb is also applied in animal organ distribution studies to solve some questions in pharmacology. {sup 124}Sb decays by {beta}-emission and it produces several photons (X and gamma rays) with energy varying from 27 to 2700 keV. Efficiency curves to measure point {sup 124}Sb solid sources were obtained from a {sup 166m}Ho standard that is a multi-gamma reference source. These curves depend on radiation energy, sample geometry, photon attenuation, dead time and sample-detector position. Results for activity determination of {sup 124}Sb samples using efficiency curves and a high purity coaxial germanium detector were consistent in different counting geometries. Also uncertainties of about 2% (k=2) were obtained.

  1. A study for natural radioactivity levels in some soil samples using gamma spectrometry

    International Nuclear Information System (INIS)

    Mohamed, Yousif Hassab El Rasoul

    1997-05-01

    The purpose of this study was to investigate a few selected soil samples and to study their natural radioactivity using gamma spectrometry. The first sample was a rock phosphate from Nuba mountains region which is being considered as a low cost fertilizer. Another sample came from Miri lake area (Nuba mountains) which is known to have elevated natural radioactivity level. The other four samples came from different other regions in Sudan for comparison. The idea was to identify the radioactive nuclides present in these soil samples, to trace their sources and to determine the activity present in them. (Author)

  2. Survey of natural radioactivity levels in Ilex paraguariensis (St. Hil.) by gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Scheibel, Viviane; Appoloni, Carlos Roberto

    2007-01-01

    The mate tea (Ilex paraguariensis - St. Hil.) is a beverage broadly cultivated and consumed in Brazil. The radioactive traces present in three trademarks of toasted mate tea produced at the south of Brazil were analyzed. Measurements were carried out by gamma-ray spectrometry. The average value for the 40 K activity measured for marks A, B and C was 1216 ± 8, 1047 ± 14 and 666 ± 13 Bq.kg -1 , respectively. The 137 Cs activity was lower than the limit of detection. (author)

  3. Self-absorption corrections of various sample-detector geometries in gamma-ray spectrometry using sample Monte Carlo Simulations

    International Nuclear Information System (INIS)

    Ahmad Saat; Appleby, P.G.; Nolan, P.J.

    1997-01-01

    Corrections for self-absorption in gamma-ray spectrometry have been developed using a simple Monte Carlo simulation technique. The simulation enables the calculation of gamma-ray path lengths in the sample which, using available data, can be used to calculate self-absorption correction factors. The simulation was carried out on three sample geometries: disk, Marinelli beaker, and cylinder (for well-type detectors). Mathematical models and experimental measurements are used to evaluate the simulations. A good agreement of within a few percents was observed. The simulation results are also in good agreement with those reported in the literature. The simulation code was carried out in FORTRAN 90,

  4. Inventory control through gamma spectrometry at the enriched uranium laboratory

    International Nuclear Information System (INIS)

    Vicens, H.E.; Korob, R.O.; Goldschmidt, A.E.

    1987-01-01

    The enriched uranium laboratory processes alternatively uranium 90% and 20% enriched in U-235. The control of the isotopic composition of lots is made through mass spectrometry. In the laboratory operation wastes of both enrichments are generated and the recovery is performed with a time delay. To strengthen the administrative controls, avoid errors related to personnel replacement and/or deferred operations, it seemed suitable to adjust the gamma spectrometry as a fast, simple and available method to determine the enrichment. The laboratory work includes a wet and a dry process. The waste recovery necessarily involves the handling of liquid samples. For this reason, it was decided to determine the calibration curve for uranyl nitrate samples of fixed concentration and geometry. The samples were prepared from material purified through double precipitation of uranium peroxide and subsequent ignition to U 3 O 8 in platinum crucible, in tubular oven during 8 hours at 720 deg C. The preparation of samples, the measurement description, the discussion of results and the analysis of errors due to the presence of insoluble material and concentration changes are included. (Author)

  5. Determination of Natural Radioactivity in Building Materials with Gamma Spectrometry

    International Nuclear Information System (INIS)

    Turki, Faten

    2010-01-01

    In the setting of this work, the natural radioactivity of building materials used in Tunisia has been measured by gamma spectrometry. These products have been ground and dried at 100 degree for 12 h. Then, they have been homogenized, weighed and finally conditioned during 23 days in order to reach the radioactive equilibrium. The measures' results proved that all building materials studied except bauxite and the ESC clay, possess doses lower than the acceptable limit (1 mSv.an-1). However, the possibility of reinforcement of the natural radioactivity in some industry of building can exist. To insure that the cement, the most used in the world, don't present any radiological risk on the workers' health, a survey has been made in the factory - les Ciments de Bizerte - about its manufacture's process. The results of this survey showed that this product can be considered like a healthy product.

  6. In-situ investigation of crack propagation in {gamma}-TiAl alloys using atomic force, focus ion beam and scanning electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Farasat; Goeken, Mathias [Lehrstuhl Allgemeine Werkstoffeigenschaften, Friedrich-Alexander-Universitaet Erlangen-Nuernberg (Germany); Pyczak, Florian [GKSS Research Centre Geesthacht, Geesthacht (Germany)

    2009-07-01

    The present study is focused on crack propagation mechanism in Ti-45Al-1Cr and Ti-45Al-5Nb alloys with lamellar microstructure. Atomic force microscopy (AFM) is a versatile technique to study the crack propagation in-situ. AFM was employed to investigate the local deformations near the crack tip. Scanning electron microscopy (SEM) supplements the in-situ observations and was used to get a basic understanding of the crack propagation path over larger distances.A focused ion beam (FIB) was used to investigate the structures and deformation traces underneath the surface. It is concluded that the {gamma}/{alpha}2 interfaces act as favorable sites for new interfacial crack nucleation and also for interlamellar crack propagation. Nucleation of new cracks was often preceded by the interaction of deformation twins with interfaces and also by strong shear band activity in the {gamma}-TiAl lamellae visible as significant surface topography in AFM.Mostly the underneath crack path follows the {gamma}/{alpha}2 interface similar to the situation observed at the surface. The local misorientation measured with electron backscattered diffraction (EBSD) shows {gamma}-lamellae as the region of high deformation as compare to neighboring {alpha}2 -lamellae around the crack tip and its surroundings.

  7. Determination of natural radioactivity in building materials used in Tunisian dwellings by gamma ray spectrometry

    International Nuclear Information System (INIS)

    Hizem, N.; Fredj, A. B.; Ghedira, L.

    2005-01-01

    The radioisotopic content of 17 samples of natural and manufactured building materials collected in Tunisia have been analysed by using gamma spectrometry. From the measured gamma ray spectra, activity concentrations are determined for 232 Th, 226 Ra, 235 U and 40 K. The total effective dose and the activity concentration index are calculated applying the dose criteria recommended by the European Union for building materials. The results of 226 Ra, 232 Th and 40 K found in Tunisian building materials indicate that radium and thorium concentrations do not exceed 40 Bq kg -1 , but potassium concentration varies between 50 and 1215 Bq kg -1 . The total effective dose rates per person indoors are determined to be between 0.07 and 0.86 mSv y -1 . Only two materials exceed the reference level of 0.3 mSv y -1 . The activity concentration index is <1. (authors)

  8. Determination of {sup 126}Sn half-life from ICP-MS and gamma spectrometry measurements

    Energy Technology Data Exchange (ETDEWEB)

    Bienvenu, P.; Arnal, N.; Comte, J. [CEA Cadarache DEN/DEC/SA3C/LARC, Paul Lez Durance (France); Ferreux, L.; Lepy, M.C.; Be, M.M. [CEA Saclay LIST LNE/LNHB, Gif sur Yvette (France); Andreoletti, G. [AREVA Cogema SL/UP2-800, Beaumont Hague (France)

    2009-07-01

    A new value of {sup 126}Sn half-life was determined by combination of inductively coupled plasma-mass spectrometry (ICP-MS) and gamma spectrometry measurements on purified sample solutions collected from nuclear fuel reprocessing. {sup 126}Sn was isolated through dissolution of fission product precipitates and liquid-liquid extraction with N-benzoyl-N-phenyl-hydroxylamine (BPHA). The abundance of {sup 126}Sn atoms together with the absence of interfering species in the analysed solutions made it possible to measure both mass concentration and nuclide activity with high precision and accuracy. This led to a {sup 126}Sn half-life value of 1.980 (57) x 10{sup 5} a. (orig.)

  9. Assessment of the suitability of different random number generators for Monte Carlo simulations in gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Cornejo Diaz, N.; Vergara Gil, A.; Jurado Vargas, M.

    2010-01-01

    The Monte Carlo method has become a valuable numerical laboratory framework in which to simulate complex physical systems. It is based on the generation of pseudo-random number sequences by numerical algorithms called random generators. In this work we assessed the suitability of different well-known random number generators for the simulation of gamma-ray spectrometry systems during efficiency calibrations. The assessment was carried out in two stages. The generators considered (Delphi's linear congruential, mersenne twister, XorShift, multiplier with carry, universal virtual array, and non-periodic logistic map based generator) were first evaluated with different statistical empirical tests, including moments, correlations, uniformity, independence of terms and the DIEHARD battery of tests. In a second step, an application-specific test was conducted by implementing the generators in our Monte Carlo program DETEFF and comparing the results obtained with them. The calculations were performed with two different CPUs, for a typical HpGe detector and a water sample in Marinelli geometry, with gamma-rays between 59 and 1800 keV. For the Non-periodic Logistic Map based generator, dependence of the most significant bits was evident. This explains the bias, in excess of 5%, of the efficiency values obtained with this generator. The results of the application-specific assessment and the statistical performance of the other algorithms studied indicate their suitability for the Monte Carlo simulation of gamma-ray spectrometry systems for efficiency calculations.

  10. Assessment of the suitability of different random number generators for Monte Carlo simulations in gamma-ray spectrometry.

    Science.gov (United States)

    Díaz, N Cornejo; Gil, A Vergara; Vargas, M Jurado

    2010-03-01

    The Monte Carlo method has become a valuable numerical laboratory framework in which to simulate complex physical systems. It is based on the generation of pseudo-random number sequences by numerical algorithms called random generators. In this work we assessed the suitability of different well-known random number generators for the simulation of gamma-ray spectrometry systems during efficiency calibrations. The assessment was carried out in two stages. The generators considered (Delphi's linear congruential, mersenne twister, XorShift, multiplier with carry, universal virtual array, and non-periodic logistic map based generator) were first evaluated with different statistical empirical tests, including moments, correlations, uniformity, independence of terms and the DIEHARD battery of tests. In a second step, an application-specific test was conducted by implementing the generators in our Monte Carlo program DETEFF and comparing the results obtained with them. The calculations were performed with two different CPUs, for a typical HpGe detector and a water sample in Marinelli geometry, with gamma-rays between 59 and 1800 keV. For the Non-periodic Logistic Map based generator, dependence of the most significant bits was evident. This explains the bias, in excess of 5%, of the efficiency values obtained with this generator. The results of the application-specific assessment and the statistical performance of the other algorithms studied indicate their suitability for the Monte Carlo simulation of gamma-ray spectrometry systems for efficiency calculations. Copyright 2009 Elsevier Ltd. All rights reserved.

  11. Radioactive characterization of samples in various geometry by gamma ray spectrometry

    International Nuclear Information System (INIS)

    Dulama, Cristian; Dobrin, Relu; Toma, Alexandru

    2001-01-01

    There are certain limitations concerning the usage of standard source method for efficiency calibration of gamma - ray spectrometers measuring in extended geometry. These limitations arise from the great diversity of forms, dimensions and densities of the objects which are to be measured. One of the steps in fuel fabrication cycle is the radioactive waste conditioning. At Institute for Nuclear Research INR a radioactive waste management facility operates both for its own purposes and for providing external services. This facility is able to perform conditioning of liquid and solid wastes for interim storage. During the waste conditioning operations there are certain stages when the radioactive measurement of the storage drums is demanded. In order to be able to establish the radioactive content within storage drums during the various procedures that are performed on them at our waste treatment facility we designed and manufactured a mobile equipment for 'in situ' spectrometry. A portable high purity germanium detector was used together with a compact workstation Canberra INSPECTOR incorporating a multi-channel analyzer, a spectroscopic amplifier and a high voltage power supply. Spectral data are processed on-line with a SubNote IBM 486 compatible PC using GeniePC, an OS/2 based spectroscopy software from Canberra. A compact, modular lead housing for the detector was designed and manufactured at INR, using uncontaminated Pb and an inner layer of copper. In front of the detector a lead collimator with cylindrical hole was used to reduce the range of variation for incidence angle. Hence several collimators were manufactured with 10, 20, 40 and 60 mm diameter holes to be able to ensure a proper counting rate in a large range of drum's specific activities by simply changing the collimator. For the efficiency calibration of the spectrometric chain a computer program was written, based on a Monte Carlo algorithm, using a semiempirical method to determinate the effective

  12. Accuracy in gamma spectrometry: Pileup, dead time, and fast electornics

    International Nuclear Information System (INIS)

    Lindstrom, R.M.

    1993-01-01

    An important source of inaccuracy in neutron activation analysis is the nonlinear throughput of the counting system, especially at high counting rates. Losses, due to the finite time needed for events to happen, occur in all parts of the spectrometer system: the germanium detector crystal, preamplifier, amplifier, analog-digital converter (ADC), and MCA or computer. The slowest unbuffered units are the ADC and the amplifier, followed by the crystal. Even with modern fast electronics, losses can be important, although compensating circuits can greatly improve accuracy if they are used correctly. The ADC dead time is less of a problem than it was a decade ago. For example, a modern successive-approximation ADC in the author's laboratory takes 6 μs to digitize a gamma ray in the middle of an 8192-channel spectrum, compared with 60 μs for the Wilkinson device that it replaced. Dead-time circuits in MCAs for many years have compensated very well for this dead time. Pulse pileup is as important as ADC dead time. Random coincidence, the accidental arrival of the signal from two nonrelated gamma rays at the amplifier in a time short compared to the shaping time, results in a composite pulse that distorts the spectrum. For accurate spectrometry, each such random-sum pulse should be excluded from the spectrum (pileup rejection), and the system dead time must be adjusted to compensate for the time the system is busy analyzing this rejected event (pileup live-time correction)

  13. Specialised software utilities for gamma-ray spectrometry. Computer codes to IAEA-TECDOC-1275

    International Nuclear Information System (INIS)

    2002-03-01

    A Co-ordinated Research Project (CRP) on 'Software Utilities for Gamma-Ray Spectrometry' was initiated by the International Atomic Energy Agency in 1996. In the CRP several basic applications of nuclear data handling were assayed which also dealt with the development of PC computer codes for various spectrometric purposes. This CD-ROM contains the following computer codes, produced under the CRP: ANGES, a program for the user controlled analysis of gamma-ray spectra from HPGe detectors; NUCL M AN, a program for the generation of gamma-ray libraries (using new, evaluated data) for specific applications; TRUE C OINC, a program to calculate true coincidence corrections; VOLUME, a program to calculate the full-energy peak efficiency calibration curve for homogeneous cylindrical sample geometries including self-attenuation correction; WINDIMEN, a program for the library driven analysis of gamma-ray spectra and for the quantification of radionuclide contents in the sample. RESFIT and DPPUNFOL, a set of programs for the definition of the detector resolution function and for unfolding of experimental annihilation spectra; MLMTEST, a program for the analysis of low-level NaI-spectra together with an extensive library of example reference spectra as well as a spectrum synthesizer

  14. Mapping of contaminated sites using mobile gamma spectrometry: Marcassin system

    International Nuclear Information System (INIS)

    Panza, F.; Demongeot, S.; Crosland, E.; Foissard, B.

    2015-01-01

    Document available in abstract form only. Full text of publication follows: As part of the development of a tool for use in a nuclear emergency, post-accident situations and contaminated sites, the Institute for Radiation Protection and Nuclear Safety (IRSN) has designed an instrument for mapping natural and artificial radioactivity in soil using in situ gamma spectrometry. The development of this mobile system is based on various studies initiated by IRSN. The tool, named MARCASSIN (Moyen Autoporteur pour la Realisation de Cartographies de l'Activite Sur Sites contamINes, or automotive resource for mapping radioactivity at contaminated sites), has already been used to characterise various types of sites: contaminated soil (Fukushima), old open-pit mines (centre of France) and environmental sites (Paris region). Mounted on a quad-type vehicle, the instrument is composed of a spectrometer, a radiation meter and a global positioning system. Using coordinates and nuclear data, results are given in the form of mapping indicating type of radionuclides, radioactivity level, dose rate and contamination distribution in real-time. To improve detection level above sites where radioactivity levels are low, the system also is capable of processing data. Two of these methods are as follows: the first, 're-meshing', improves the estimate of soil radioactivity by increasing measurement statistics. The results agree with the reference values (soil samples measured in the laboratory), even for normal environmental levels of radioactivity. The second method, for which a patent is pending, is based on a deconvolution of mapping data. Re-processing deducts the impulse response of MARCASSIN from the radiation flux measurements in order to restore the value sought, which is the soil emission rate by radiological energy or activity. A theoretical example demonstrates the possibilities of this method. (authors)

  15. Developments in gamma-ray spectrometry: systems, software, and methods-II. 3. Low-Energy Gamma-Ray Spectrometry Using a Compton-Suppressed Telescope Detector

    International Nuclear Information System (INIS)

    Sigg, R.A.; DiPrete, D.P.

    2001-01-01

    The Savannah River Technology Center (SRTC) utilizes gamma-ray spectrometry in studying numerous areas of applied interest to the Savannah River Site (SRS). For example, analyses of long-lived gamma-ray-emitting fission products and actinides are required to meet waste characterization, process holdup, environmental restoration, and decontamination and decommissioning efforts. A significant portion of the overall effort centers on measurements of gamma rays having energies below several hundred kilo-electron-volts. To assist these efforts, the SRTC recently acquired a spectrometer system that provides lower natural and Compton scattered background levels while achieving relatively high counting efficiencies for low-energy gamma rays. The combination of high efficiency and low background provides factor-of- 2-to-4 improvements in minimum detectable activities and allows meeting programmatic objectives with shorter measurement times. Numerous Compton-suppression spectrometers have been reported since the concept was first advanced. The spectrometer consists of two high-purity germanium detectors in a telescope configuration surrounded by a background /Compton-suppression sodium iodide detector. The front germanium detector is a 20-mm-thick x 60-mm-diam broad energy spectrometer, and the rear detector is a 40% efficient 61- mm-diam x 60-cm-thick closed-end coaxial spectrometer. The cryostat housing the germanium detectors (a) includes a carbon composite window for transmitting low-energy gamma rays, (b) is in a J-type configuration to mask the germanium detectors from natural activities in the cryo-pumping media, and (c) is fabricated from materials selected for low background. The telescope detector is in the 8.6-cm-inside-diameter annulus of a 22.9- x 22.9-cm sodium iodide detector encased in a 10-cm-thick lead shield. The counting system is located in a basement counting room having ∼60-cm-thick concrete walls. Initial tests show that the low-energy segment of

  16. Determination of burnup for IEAR-1 fuel elements by non destructive method of gamma spectrometry

    International Nuclear Information System (INIS)

    Madi Filho, T.; Holland, L.

    1982-01-01

    Burnup determination, by non-destructive gamma spectrometry of spent fuel with high and low activity of IEAR-1 reactor, using Cs-137 as burnup monitor, were done. To measure the Cs-137 distribution in these elements a Ge(Li) detector, with volume equal to 73,7 cm 3 , in two measurement systems with defined geometry and good colimation, was used. The IEA-14 taken from the core about 20 years ago, presents a gamma spectra due to Cs-137. The IEA-80, with cooling time approximately to 5 years, shows a more complex gamma spectrum due to other fission products still found in significant quantities. The IEA-14 measures were done in a measurement system used outside the reactor pool (S.I.), being the global efficiency of this system obtained by using a plane, calibrated and extense Ag-110 m source. Detailed measures of gamma transmission, using Cs-137 as a calibrated and punctiforme source, showed the high homogenity of the fuel plates. (E.G.) [pt

  17. Use of wavelet based iterative filtering to improve denoising of spectral information for in-vivo gamma spectrometry

    International Nuclear Information System (INIS)

    Paul, Sabyasachi; Sarkar, P.K.

    2012-05-01

    The characterization of radionuclide in the in-vivo monitoring analysis using gamma spectrometry poses difficulty due to very low activity level in biological systems. The large statistical fluctuations often make identification of characteristic gammas from radionuclides highly uncertain, particularly when interferences from progenies are also present. A new wavelet based noise filtering methodology has been developed for better detection of gamma peaks while analyzing noisy spectrometric data. This sequential, iterative filtering method uses the wavelet multi-resolution approach for the noise rejection and inverse transform after soft thresholding over the generated coefficients. Analyses of in-vivo monitoring data of 235 U and 238 U have been carried out using this method without disturbing the peak position and amplitude while achieving a threefold improvement in the signal to noise ratio, compared to the original measured spectrum. When compared with other data filtering techniques, the wavelet based method shows better results. (author)

  18. Evaluation of gamma-spectrometry equipment for on-site inspection

    International Nuclear Information System (INIS)

    Burnett, J.L.; Milbrath, B.D.; Mueller, W.F.

    2017-01-01

    An On-site Inspection (OSI) is an important component of the verification regime of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), with the objective of gathering evidence of a possible Treaty violation. This includes the use of gamma-spectrometry equipment to identify 17 particulate radionuclides that are indicative of a nuclear explosion. This research provides an evaluation of high- (germanium), medium- (cadmium zinc telluride) and low-resolution (sodium iodide and lanthanum bromide) detectors using modelled radionuclide signatures from a nuclear explosion and Monte Carlo simulations of a detector response. The complex radionuclide signatures are shown to only be distinguishable using a high-resolution system for 1 week and 1 year post-detonation cases. (author)

  19. Assessing soil erosion at landscape level: A step forward in the up-scaling of 137Cs measurements through the use of in-situ lanthanum bromide scintillator

    Science.gov (United States)

    Gonsalves, Basil C.; Darby, Iain G.; Toloza, Arsenio; Mabit, Lionel; Kaiser, Ralf B.; Dercon, Gerd

    2014-05-01

    Measuring Fallout Radionuclides (FRN), in particular 137Cs, is a well-established method to estimate soil erosion and deposition in agricultural landscapes. While extremely sensitive, laboratory based gamma-ray spectrometry requires careful handling and preparation of measurement samples with a lengthy measuring time (~1 day), In-situ gamma-ray spectrometry can give near instantaneous results, allowing prompt decisions to be made and identification of critical spots of soil erosion, while the equipment is in the field. The aim of this investigation was to compare the precision of the in-situ FRN measurements, made by a cost-effective lanthanum bromide (LaBr3 (Ce)) scintillation detector of 137Cs against those from conventional (high-purity germanium HPGe detector) but laborious laboratory based gamma-ray spectrometry for assessing soil erosion. As preliminary test, five cores of a gleyic Cambisol - per increments of 5 cm until 1 m depth - were collected at the experimental research station of the Austrian Agency for Health and Food Safety located in Grabenegg 130 km west of Vienna. Three soil cores were sampled at the study site and, in the vicinity of this experimental site, two additional cores were collected at two different undisturbed reference sites. Laboratory gamma analyses were carried out during 50 000 seconds using a HPGe coaxial detector. The gamma measurements performed at the laboratory confirmed the undisturbed status of the two selected reference sites (i.e. exponential decrease with depth of the 137Cs content). Using the surface area of the sampling tool, the 137Cs areal activities of the cores sampled in the study site have been established at 2134±465 Bq m-2, 1835±356 Bq m-2 and 2553±340 Bq m-2, and, for the two reference sites at 3221±444 Bq m-2 and 3946±527 Bq m-2. At the same location and prior to collect the five soil cores, in-situ measurements using a lanthanum bromide (LaBr3 (Ce)) scintillator were performed. The detector was placed

  20. Characterization of Uranium-Bearing Material by Passive Non-Destructive Gamma Spectrometry

    International Nuclear Information System (INIS)

    Lakosi, L.; Zsigrai, J.; Nguyen, C.T.

    2009-01-01

    Characterization of nuclear materials is equally important in nuclear safeguards (inventory verification) and in nuclear security (revealing illicit trafficking). Analysis of materials is a key issue in both fields. Natural (NU), depleted (DU), low-enriched (LEU), and high-enriched uranium (HEU) samples were analysed by high resolution gamma spectrometry (HRGS). Isotopic composition and total U-content of reactor fuel pellets and powder were determined. A unique HRGS method was developed for the first time for determining the production date of the material of unknown origin. Identifying reprocessed uranium proved to be possible by HRGS as well.

  1. Fisson product control by gamma spectrometry in Purex process solutions

    International Nuclear Information System (INIS)

    Goncalves, Maria A.; Matsuda, H.T.

    1982-01-01

    A radiometric method for fission product analysis by gamma spectrometry, to be applied for fission product control at an irradiated material processing facility, is described. Counting geometry was defined taking into account the activities of process solutions to be analysed, the remotely operated aliquotation device of the analytical cell and the available detection system. Natural and 19,91% enriched uranium samples were irradiated in order to simulate the composition of Purex process solutions. After a short decay time the samples were dissolved with HNO 3 and then conditioned in standard flasks with defined geometry. The spectra were obtained by a Ge(Li) semiconductor detector and analysed by the GELIGAM software system, using a floppy-disk connected to a PDP-11/05 computer. Libraries were prepared and calibrations were made with standard sources to fit the analysis of fission products in irradiated uranium solutions. It was possible to choose the best program to be used in routine analysis with the obtained data. (Author) [pt

  2. Gamma spectrometry today

    International Nuclear Information System (INIS)

    Hemingway, J.

    1990-01-01

    This paper reviews the important advances in gamma spectroscopy made in recent years. Improvements in detectors and other components and the addition of on-line computer control systems is discussed. (UK)

  3. Low-energy X-ray and gamma spectrometry using silicon photodiodes

    International Nuclear Information System (INIS)

    Silva, Iran Jose Oliveira da

    2000-08-01

    The use of semiconductor detectors for radiation detection has increased in recent years due to advantages they present in comparison to other types of detectors. As the working principle of commercially available photodiodes is similar to the semiconductor detector, this study was carried out to evaluate the use of Si photodiodes for low energy x-ray and gamma spectrometry. The photodiodes investigated were SFH-205, SFH-206, BPW-34 and XRA-50 which have the following characteristics: active area of 0,07 cm 2 and 0,25 cm 2 , thickness of the depletion ranging from 100 to 200 μm and junction capacitance of 72 pF. The photodiode was polarized with a reverse bias and connected to a charge sensitive pre-amplifier, followed by a amplifier and multichannel pulse analyzer. Standard radiation source used in this experiment were 241 Am, 109 Cd, 57 Co and 133 Ba. The X-ray fluorescence of lead and silver were also measured through K- and L-lines. All the measurements were made with the photodiodes at room temperature.The results show that the responses of the photodiodes very linear by the x-ray energy and that the energy resolution in FWHM varied between 1.9 keV and 4.4 keV for peaks corresponding to 11.9 keV to 59 keV. The BPW-34 showed the best energy resolution and the lower dark current. The full-energy peak efficiency was also determined and it was observed that the peak efficiency decreases rapidly above 50 keV. The resolution and efficiency are similar to the values obtained with other semiconductor detectors, evidencing that the photodiodes used in that study can be used as a good performance detector for low energy X-ray and gamma spectrometry. (author)

  4. Rapid non-destructive quantitative estimation of urania/ thoria in mixed thorium uranium di-oxide pellets by high-resolution gamma-ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Shriwastwa, B.B.; Kumar, Anil; Raghunath, B.; Nair, M.R.; Abani, M.C.; Ramachandran, R.; Majumdar, S.; Ghosh, J.K

    2001-06-01

    A non-destructive technique using high-resolution gamma-ray spectrometry has been standardised for quantitative estimation of uranium/thorium in mixed (ThO{sub 2}-UO{sub 2}) fuel pellets of varying composition. Four gamma energies were selected; two each from the uranium and thorium series and the time of counting has been optimised. This technique can be used for rapid estimation of U/Th percentage in a large number of mixed fuel pellets from a production campaign.

  5. Rapid non-destructive quantitative estimation of urania/ thoria in mixed thorium uranium di-oxide pellets by high-resolution gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Shriwastwa, B.B.; Kumar, Anil; Raghunath, B.; Nair, M.R.; Abani, M.C.; Ramachandran, R.; Majumdar, S.; Ghosh, J.K.

    2001-01-01

    A non-destructive technique using high-resolution gamma-ray spectrometry has been standardised for quantitative estimation of uranium/thorium in mixed (ThO 2 -UO 2 ) fuel pellets of varying composition. Four gamma energies were selected; two each from the uranium and thorium series and the time of counting has been optimised. This technique can be used for rapid estimation of U/Th percentage in a large number of mixed fuel pellets from a production campaign

  6. A comparative study for the correction of random gamma ray summing effect in HPGe - detector based gamma ray spectrometry

    International Nuclear Information System (INIS)

    Rajput, M.U.

    2007-01-01

    Random coincidence summing of gamma rays is a potential source of errors in gamma ray spectrometry. The effect has a little significance at low counting rates but becomes increasingly important at high counting rates. Careful corrections are required to avoid the introduction of errors in quantitative based measurements. Several correction methods have been proposed. The most common is the pulser method that requires a precision Pulse Generator in the electronic circuitry to provide reference peak. In this work, a comparative study has been carried out both by using pulser method and utilizing radioactive source based method. This study makes the use of 137 Cs radionuclide as a fixed source and the 241 Am as a varied source. The dead time of the system has been varied and the acquisition of the spectra at each position yielded the resulted peak areas with pulsed pile up losses. The linear regression of the data has been carried out. The study has resulted in establishing a consistent factor that can be used as the characteristic of the detector and thereby removes the need of the calibrated or precise Pulse Generator. (author)

  7. Detection limits should be a thing of the past in gamma-ray spectrometry in general as well as in neutron activation analysis

    NARCIS (Netherlands)

    Blaauw, Menno

    2016-01-01

    In gamma-ray spectrometry with high-resolution detectors, full-energy peaks are often to be detected by a peak-search algorithm, with a threshold for detection. Detection limits can be derived from this. Detection limits are often computed along with measured activities or concentrations. When an

  8. Prompt gamma-ray spectrometry for measurement of B-10 concentration in brain tissue and blood

    International Nuclear Information System (INIS)

    Nakagawa, Yoshinobu; Kitamura, Katsuji; Kobayashi, Toru; Matsumoto, Keizo; Hatanaka, Hiroshi.

    1993-01-01

    Boron-10 (B-10) concentration in the brain tissue and blood was measured continuously for 24 hours after injection of the B-10 compound in live rabbits using prompt gamma-ray spectrometry. Following injection of B-10 compound (Na 2 B 12 H 11 SH, 50mg/kg) dissolved in physiological saline, B-10 concentration was continuously measured in the brain tissue. Intermittently the concentration of B-10 in blood and cerebro-spinal fluid (CSF) was also measured. In 10 minutes after the injection of B-10 compound, the level of B-10 concentration reached the peak of 400-500 ppm in blood and 20-30 ppm in the normal brain tissue. In 60 minutes the level of B-10 concentration rapidly decreased and then a gradual decline was observed. The value was 15-30 ppm at 3 hours after injection, 5-10 ppm at 6 hours and 2-5 ppm at 24 hours in the blood. The concentration in the brain tissue was 3-8 ppm at 3 hours, 2-5 ppm at 6 hours and below 1.5 ppm at 24 hours. B-10 concentration in cerebro-spinal fluid was below 1 ppm. B-10 concentration was also measured in the brain tumor and blood in the human cases at boron neutron capture therapy (BNCT). These data studied by prompt gamma-ray spectrometry are very important and useful to decide the irradiation time. (author)

  9. In-situ gamma-ray survey of rare-earth tailings dams – A case study in Baotou and Bayan Obo Districts, China

    International Nuclear Information System (INIS)

    Li, Baochuan; Wang, Nanping; Wan, Jianhua; Xiong, Shengqing; Liu, Hongtao; Li, Shijun; Zhao, Rong

    2016-01-01

    An in-situ gamma-ray spectrometer survey with a scintillation detector of NaI(Tl) (Φ75 mm × 75 mm) was carried out in the Baotou and Bayan Obo Districts in order to estimate the levels of natural radionuclides near rare-earth (RE) tailings dams. In the RE tailings dam of Baotou, the mean concentrations of "2"3"8U and "2"3"2Th were 3.0 ± 1.0 mg/kg (range: 1.9–4.6 mg/kg) and 321 ± 31 mg/kg (range: 294–355 mg/kg), respectively. In the Bayan Obo tailings dam, the mean concentrations of "2"3"8U and "2"3"2Th were 5.7 ± 0.5 mg/kg (range: 5.3–6.1 mg/kg) and 276 ± 0.5 mg/kg (range: 275.5–276.3 mg/kg), respectively. The average "2"3"2Th concentrations in the mining areas of the Bayan Obo Mine and the living areas of the Bayan Obo Town were 18.7 ± 7.5 and 26.2 ± 9.1 mg/kg, respectively. The "2"3"2Th concentration recorded in the tailings dams was much higher than the global average (7.44 mg/kg). Our investigation shows that the "2"3"2Th concentration in the tailings in the Baotou dam was 34.6 times greater than that in the local soil (in Guyang County); the average concentrations of "2"3"2Th in the soil in the Baotou District and Bayan Obo Districts were about 1.35 and 2.82 times greater, respectively, than that in the soil in Guyang County. Based on our results, the highest estimated effective dose due to gamma irradiation was 1.15 mSv per year, estimated from the data observed in the Baotou tailings dams. The results of this preliminary study indicate the potential importance of radioactivity in RE tailings dams and that remedial measures may be required. - Highlights: • In-situ gamma-ray spectrometry to measure natural radionuclides in rare-earth tailings dam. • Comparisons were among the tailings dam, mining area and living areas in Baotou and Bayan Obo. • "2"3"2Th concentrations in tailings dams in Baotou and Bayan Obo were much higher than global average. • Results provide a baseline useful to assess the radiation

  10. Shaly sand evaluation using gamma ray spectrometry, applied to the North Sea Jurassic

    International Nuclear Information System (INIS)

    Marett, G.; Chevalier, P.; Souhaite, P.; Suau, J.

    1976-01-01

    In formations where radioactive minerals other than clay are present, their effects on log responses result in a reduction of the accuracy of determination of the shale fraction. The gamma ray log, which is one of the primary indicators for shaliness determination, is the most affected; other logs used in shaliness indicators are also influenced, particularly when heavy minerals are present, such as those encountered in the micaceous sandstones of the North Sea Jurassic. For comparison purposes, possible ways to correct for heavy radioactive minerals using a conventional logging suite are described. Computer processed examples illustrate the results obtained. A different approach is through an analysis of the natural gamma ray spectrum of the formation, as determined with the gamma ray spectrometry tool. Natural gamma rays originate from the radioactive isotope of potassium and the radioactive elements of the uranium and thorium series. Each of these three elements contributes its distinctive spectrum to that of the formation in proportion to its abundance. Thus, by analysis of the formation spectrum, the presence of each can be detected and its amount estimated. This makes possible quantitative corrections to the shaliness indicators. A computer program which performs the necessary computations is described, and several log examples using this technique are presented

  11. Gamma spectrometry for chronology of recent sediments

    International Nuclear Information System (INIS)

    Pittauerova, Daniela

    2013-01-01

    This thesis deals with several aspects of gamma spectrometric analysis of natural and artificial isotopes in sediments and their use as tracers for qualification and quantification of accumulation and mixing processes in different aquatic environments. Sediment cores from three distinct areas including terrigenous sediments deposited on the continental slope off NW Africa, deep sea sediments off Sumba Island and five stations from the Gulf of Eilat in the Red Sea area were measured and interpreted within this dissertation. The main concern in gamma spectrometry of voluminous environmental samples is a reliable efficiency calibration. This is specially relevant for the analysis of low energy gamma emitters (<100 keV). 210 Pb, an important isotopic tracer to cover the period of the last century, is one of them. Within this work mathematical efficiency calibration was applied using a commercial software package. A series of validation tests was performed and evaluated for point and voluminous samples. When using 210 Pb as a tracer it is necessary to determine its excess portion, which is not supported by ingrowth from the parent nuclide 226 Ra. Its analysis is mostly performed via short lived daughter isotopes that follow after the intermediate gaseous member 222 Rn. Preventing the escape of radon from the sample is a critical step before analysis due to a negative effect of supported 210 Pb underestimation on the chronology, which was also documented in this thesis. Time series registering ingrowth of 214 Pb and 214 Bi towards radioactive equilibrium with 226 Ra in different containers were evaluated for analyses of 226 Ra. Direct analyses of 226 Ra was compared to its detection via daughter products. A method for aligning parallel radionuclide depth profiles was described and applied successfully in two case studies from the continental slope off NW Africa and off Sumba Island, Indonesia. This is primarily important when combined profiles obtained from short

  12. Applications of gamma-ray spectrometry in real-time environmental monitoring

    International Nuclear Information System (INIS)

    Heath, R.L.; Dyer, N.C.

    1974-01-01

    The operation of large nuclear installations involves significant inventories of radioactive materials. Effective monitoring of effluent streams to permit evaluation of potential hazards which might result from discharge of radioisotopes is a requirement for safe operation of such facilities. The purpose of this paper is to present a summary of a program being conducted at the Idaho National Engineering Laboratory (INEL) to apply gamma-ray spectrometry to real-time isotopic monitoring of nuclear installations. The application of the lithium-drifted Ge spectrometer in the laboratory for isotopic assay is well established. To apply these techniques to routine on-line isotopic measurements requires the solution of a number of significant problems. These may be summarized as follows: the development of a remote pulse-height analyzer system; the development of adequate methods for analysis of pulse-amplitude spectra to permit isotopic assay and interpretation of results; and determination of basic nuclear decay data requirements for nuclides of interest to insure acceptance of isotopic assay results

  13. Simultaneous determination of RA-226, natural uranium and natural thorioum by gamma-ray spectrometry INa(Tl) in solid samples

    International Nuclear Information System (INIS)

    Salvador, S.; Navarro, T.; Alvarez, A.

    1990-01-01

    A method has been described to determine activities of Ra-226, natural uranium, and natural thorium, by gamma-ray spectrometry. The system was calibrated for efficiency by using synthetic calibrated standards. It is necessary, in the samples, to assume secular equilibrium between Ra-226 and Th-232 and its daughters nuclides, and U-238 and its immediate daughter Th-234, because the photopeaks measured are from these dsaugthers. Our results indicate that a non destructive gamma spectrometric method can ofter replace the radiochemical techniques used in measuring radiactivities in this type of samples. (Author). 9 refs

  14. Determination of 226Ra by gamma spectrometry: study of packaging vial of sample for analysis

    International Nuclear Information System (INIS)

    Carneiro, Andre Cavalcanti

    2015-01-01

    Determination of radioactivity levels of 226 Ra by gamma spectrometry in a sample is based on measurements of 214 Pb and 214 Bi, daughters of 222 Rn. Because radon is a gas, it can leak from the sample vial or accumulate on the upper empty it. If the vial has any crack, there will be loss of gas, which will cause error in determining the 226 Ra concentration. One possible cause of cracks in the vials, that houses standards and samples, is the radiolysis action in the vial material, usually a polymer. As the demand 226 Ra analysis in different matrices (geological samples, food, plants, etc.) is increasing, it was decided to study some polymer vials available on the market, to verify the feasibility to be used when is applied the analysis method using gamma spectrometry. Four types of polymer vials have been studied. The radiation doses in walls of the vials caused by natural radionuclides present in the sample were simulated using gamma irradiation. Tests, such as compressive strength test and tightness, were applied to the irradiated and non-irradiated vials. First, to verify the effect of radiolysis on the vial material and also if there was 222 Rn diffusion in their walls. These preliminary results pointed out that the acrylic vials are the best option of packaging samples for analysis. This study should be repeated in a larger number of samples for a better evaluation. (author)

  15. Natural radioactivity in extreme south of Bahia, Brazil, using gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Vasconcelos, Danilo C.; Oliveira, Arno H.; Silva, Mario R.S.; Penna, Rodrigo; Santos, Talita O.; Pereira, Claubia; Rocha, Zildete; Menezes, Maria Angela B.C.

    2009-01-01

    The concentrations activity of natural radionuclides in beach sand in extreme south of Bahia-Brazil was measured using gamma-ray spectrometry. The activity concentrations of 226 Ra, 232 Th and 40 K in beach sand ranged from 14.5 to 8,318.4, 20.5 to 18,450.0, 15.4 to 3,109.0 Bq/kg, with a mean value of 1,078.2, 2,429.6, and 417.0 Bq/kg respectively. The values of radiation hazard indexes in sands of Alcobaca, Caraiva and Cumuruxatiba are higher than the limits preconized by Beretka and Mathew. The use of these sands may be not safe in building constructions. The results show that the absorbed dose rates range from 20.4-15,116.6 nGy/h with mean value of 1762.7. The highest value of gamma dose rates among the studied beaches was found in Cumuruxatiba (15,116.6 nGy/h). The annual effective dose varied between 0.028 and 18.539 mSv/year, with a mean of 2.162 mSv/year. Values of Alcobaca, Trancoso, Caraiva and Cumuruxatiba are higher than the worldwide average for outdoor annual effective dose, 0.07 mSv/year. (author)

  16. Radon gamma-ray spectrometry with YAP:Ce scintillator

    CERN Document Server

    Plastino, W; De Notaristefani, F

    2002-01-01

    The detection properties of a YAP:Ce scintillator (YAlO sub 3 :Ce crystal) optically coupled to a Hamamatsu H5784 photomultiplier with standard bialkali photocathode have been analyzed. In particular, the application to radon and radon-daughters gamma-ray spectrometry was investigated. The crystal response has been studied under severe extreme conditions to simulate environments of geophysical interest, particularly those found in geothermal and volcanic areas. Tests in water up to a temperature of 100 deg.C and in acids solutions such as HCl (37%), H sub 2 SO sub 4 (48%) and HNO sub 3 (65%) have been performed. The measurements with standard radon sources provided by the National Institute for Metrology of Ionizing Radiations (ENEA) have emphasized the non-hygroscopic properties of the scintillator and a small dependence of the light yield on temperature and HNO sub 3. The data collected in this first step of our research have pointed out that the YAP:Ce scintillator can allow high response stability for rad...

  17. Gamma spectrometry and chemical characterization of bioactive glass seeds with Holmium-166 for oncological implants

    International Nuclear Information System (INIS)

    Valente, Eduardo S.

    2009-01-01

    Bioactive glass seeds synthesized by the sol-gel technique with Si:Ho:Ca composition with natural holmium incorporated were irradiated in the TRIGA type nuclear reactor IPR-R1 at 100kW, in the central thimble where the thermal neutron flux is 2.8x10 12 n/cm 2 .s and the epithermal neutron flux is 2.6 X 10 11 n/cm 2 .s . After an 8 hour irradiation time, with an induced activity close to 110MBq/seed, a set of seeds was submitted to Gamma Spectrometry Analysis in a counting system with an HPGe detector, ORTEC electronic instrumentation and a Camberra Multichannel Analyser, to determine all radionuclides present on the sample as well as its individual activities. Special attention was paid on the discrimination of Si, 40 Ca, 44 Ca, C and Ho as the other expected elements like 48 Ca, 2 H and 18 O were present in traces or have very short half-lives. The second sample was submitted to Plasma spectrometry to determine the 166 Ho concentration in weight. The third sample was submitted to an X-ray spectrometry in a JEOL-JXA-8900RL equipment to determine its qualitative chemical composition, in order to evaluate impurities and nominal composition. It was determined that most of the activity, after decaying of short half-life elements, was due to 166 Ho present on the sample, with a well characterized β and gamma spectra. The homogeneity of the seeds was tested on the X-ray spectrometry, and verified that there is no discrepancy in composition from distinct seeds or in a same seed. The results are relevant on the investigation of the viability of producing 166 Ho radioactive seeds for oncological implants. (author)

  18. Characterization of radioactive orphan sources by gamma spectrometry

    International Nuclear Information System (INIS)

    Cruz W, H.

    2013-01-01

    The sealed radioactive sources are widely applicable in industry. They must have a permanent control and must be registered with the Technical Office of the National Authority (OTAN). However, at times it has identified the presence of abandoned sealed sources unknown to the owner. These sources are called 'orphan sources'. Of course these sources represent a high potential risk because accidents can trigger dire consequences depending on your activity and chemical form in which it presents the radioisotope. This paper describes the process and the actions taken to characterize two orphan radioactive sources from the smelter a Aceros Arequipa. For characterization we used a gamma spectrometry system using a detector NaI(Tl) 3″ x 3″ with a multichannel analyzer Nucleus PCA-II. The radioisotope identified was cesium - 137 ( 137 Cs) in both cases. Fortunately, the sources maintained their integrity would otherwise have generated significant pollution considering the chemical form of the radioisotope and easy dispersion. (author)

  19. In situ mapping of radionuclides in subsurface and surface soils: 1994 Summary report

    International Nuclear Information System (INIS)

    Schilk, A.J.; Hubbard, C.W.; Knopf, M.A.; Abel, K.H.

    1995-04-01

    Uranium production and support facilities at several DOE sites occasionally caused local contamination of some surface and subsurface soils. The thorough cleanup of these sites is a major public concern and a high priority for the US Department of Energy, but before any effective remedial protocols can be established, the three-dimensional distributions of target contaminants must be characterized. Traditional means of measuring radionuclide activities in soil are cumbersome, expensive, time-consuming, and often do not accurately reflect conditions over very large areas. New technologies must be developed, or existing ones improved, to allow cheaper, faster, and safer characterization of radionuclides in soils at these sites. The Pacific Northwest Laboratory (PNL) was tasked with adapting, developing, and demonstrating technologies to measure uranium in surface and subsurface soils. In partial completion of this effort, PNL developed an improved in situ gamma-ray spectrometry system to satisfy the technical requirements. This document summarizes fiscal-year 1994 efforts at PNL to fulfill requirements for TTP number-sign 321103 (project number-sign 19307). These requirements included (a) developing a user-friendly software package for reducing field-acquired gamma-ray spectra, (b) constructing an improved data-acquisition hardware system for use with high-purity germanium detectors, (c) ensuring readiness to conduct field mapping exercises as specified by the sponsor, (d) evaluating the in situ gamma-ray spectrometer for the determination of uranium depth distribution, and (e) documenting these efforts

  20. 2015 In-Situ Gamma-Ray Assay of the West Cell Line in the 235-F Plutonium Fuel Form Facility

    Energy Technology Data Exchange (ETDEWEB)

    Brand, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Aucott, T. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); DiPrete, D. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-02-01

    In November and December 2015, scientists from SRNL took a series of in-situ gamma-ray measurements through the windows in front of Cells 6-9 on the west line of the PuFF facility using a shielded, 120% high-purity germanium detector. The detector efficiency was estimated using a combination of MCNP simulations and empirical measurements. Where possible, the distribution of the Pu-238 in the cells was determined using the Germanium Gamma-ray Imager (GeGI). This distribution was then fed into the MCNP model to quantify the Pu-238 in each cell. Data analysis was performed using three gamma rays emitted by Pu-238 (99.85 keV, 152.7 keV, and 766.4 keV) providing three independent estimates of the mass of Pu-238 holdup in each of the cells.

  1. Overview of gamma spectrometry measurement devices developed by ENVINET a.s

    International Nuclear Information System (INIS)

    Sidlova, V.; Slama, L.; Holecek, V.; Chaloupkova, H.

    2008-01-01

    This paper demonstrates the development and usage of the devices designed for non- destructive radiological characterization of radioactive waste. All ..systems are based on gamma-spectrometry and are divided into two categories - stable and mobile. Stable ones involve only measurement in fixed detector - package configuration. They are used for assessment of packaged waste, mainly in drums. Mobile ones are flexible and allow measurement of a wide range of objects from various positions and can be also transported to arbitrary location. The calibration of such systems is performed by means of appropriate software which allows computation of full-energy peak efficiency in various configurations. (authors)

  2. Critical review of gamma spectrometry detection approaches for in-plant surface deposition monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Gregorich, Carola [Nuclear Fuels and Chemistry at the Electric Power Research Institute, Palo Alto, CA 94304, (United States)

    2015-07-01

    Surface deposition of activated corrosion product on oxide layers of light-water reactor primary system components is the primary source for ex-core radiation fields and personnel radiation exposure. Understanding the deposition mechanism and what factors influence the deposition and release behaviors are crucial for developing effective radiation field reduction measures. One of the available tools to assess the surface deposition is in-plant gamma spectrometry, which has been performed for several decades using either sodium iodide (NaI) or high-purity germanium (HPGe) detectors. Lately, the much more mobile cadmium-zinc-telluride (CZT) detectors are increasingly employed by stations because of their ease in use and handling. However, all of these gamma detectors face the same challenges; namely large-geometry samples of inconsistent sample compositions and sometimes gaps in the information necessary to establish proper efficiency calibrations. This paper reviews current measurements and efficiency calibration approaches taken in the industry. The validity of the measurement results and the feasibility of the data's use in understanding source term behavior is examined. Suggestions are made for the development of a more robust deposit characterization and radiation field monitoring program. (authors)

  3. Burn-up measurements coupling gamma spectrometry and neutron measurement

    Energy Technology Data Exchange (ETDEWEB)

    Toubon, H.; Pin, P. [AREVA/CANBERRA, 1 rue des Herons, 78182 St Quentin-en-Yvelines Cedex (France); Lebrun, A. [IAEA, Wagramer Strasse 5, PO Box 100, Vienna (Austria); Oriol, L.; Saurel, N. [CEA Cadarache, 13108 Saint Paul Lez Durance Cedex (France); Gain, T. [AREVA/COGEMA Reprocessing Business Unit, La Hague, 50444 Beaumont Hague Cedex (France)

    2006-07-01

    The need to apply for burn-up credit arises with the increase of the initial enrichment of nuclear fuel. When burn-up credit is used in criticality safety studies, it is often necessary to confirm it by measurement. For the last 10 years, CANBERRA has manufactured the PYTHON system for such measurements. However, the method used in the PYTHON itself uses certain reactor data to arrive at burn-up estimates. Based on R and D led by CEA and COGEMA in the framework of burn-up measurement for burn-up credit and safeguards applications, CANBERRA is developing the next generation of burn-up measurement device. This new product, named SMOPY, is able to measure burn-up of any kind of irradiated fuel assembly with a combination of gamma spectrometry and passive neutron measurements. The measurement data is used as input to the CESAR depletion code, which has been developed and qualified by CEA and COGEMA for burn-up credit determinations. In this paper, we explain the complementary nature of the gamma and neutron measurements. In addition, we draw on our previous experience from PYTHON system and from COGEMA La Hague to show what types of evaluations are required to qualify the SMOPY system, to estimate its uncertainties, and to detect discrepancies in the fuel data given by the reactor plant to characterize the irradiated fuel assembly. (authors)

  4. Burn-up measurements coupling gamma spectrometry and neutron measurement

    International Nuclear Information System (INIS)

    Toubon, H.; Pin, P.; Lebrun, A.; Oriol, L.; Saurel, N.; Gain, T.

    2006-01-01

    The need to apply for burn-up credit arises with the increase of the initial enrichment of nuclear fuel. When burn-up credit is used in criticality safety studies, it is often necessary to confirm it by measurement. For the last 10 years, CANBERRA has manufactured the PYTHON system for such measurements. However, the method used in the PYTHON itself uses certain reactor data to arrive at burn-up estimates. Based on R and D led by CEA and COGEMA in the framework of burn-up measurement for burn-up credit and safeguards applications, CANBERRA is developing the next generation of burn-up measurement device. This new product, named SMOPY, is able to measure burn-up of any kind of irradiated fuel assembly with a combination of gamma spectrometry and passive neutron measurements. The measurement data is used as input to the CESAR depletion code, which has been developed and qualified by CEA and COGEMA for burn-up credit determinations. In this paper, we explain the complementary nature of the gamma and neutron measurements. In addition, we draw on our previous experience from PYTHON system and from COGEMA La Hague to show what types of evaluations are required to qualify the SMOPY system, to estimate its uncertainties, and to detect discrepancies in the fuel data given by the reactor plant to characterize the irradiated fuel assembly. (authors)

  5. Development and calibration automatic equipment's measuring in real time of the environmental radioactivity by gamma spectrometry

    International Nuclear Information System (INIS)

    Casanovas, R.; Morant, J. J.; Salvado, M.

    2013-01-01

    In this paper, we describe the general aspects of the implementation of gamma spectrometry in water, as well as the development of two measuring devices based on this technique: aerosol monitor (RARM-F) and a monitor direct measurement (RARMD2) , both patent applications. Furthermore, they described in detail the aspects of calibration of equipment, which has been made by combining experimental measurements with Monte Carlo simulations. (Author)

  6. Dating the age of a recent nuclear event by gamma-spectrometry

    International Nuclear Information System (INIS)

    Nir-El, Y.

    2006-01-01

    The age of a recent, i.e., fresh, nuclear event can be determined by measuring the activity of short-lived parent and daughter fission products. The event studied was a short irradiation, of a small sample of uranium, in a nuclear reactor. Two clocks were investigated, 92 Sr- 92 Y and 135 I- 135 Xe. Measurements of the source by gamma-spectrometry yielded very good agreement between true and measured ages. The upper and lower age limits of applicability for the clocks in question were defined. The half-life of 92 Sr was found 2.635±0.008 hours and of 135 I 6.65±0.04 hours. (author)

  7. Design of an automatic sample changer for the measurement of neutron flux by gamma spectrometry

    International Nuclear Information System (INIS)

    Gago, Javier; Bruna, Ruben; Baltuano, Oscar; Montoya, Eduardo; Descreaux, Killian

    2014-01-01

    This paper presents calculus, selection and components design for the construction of an automatic system in order to measure neutron flux in a working nuclear reactor by the gamma spectrometry technique using samples irradiated on the RP-10 nucleus. This system will perform the measurement of interchanging 100 samples in a programed and automatic way, reducing operation time by the user and obtaining more accurate measures. (authors).

  8. GammaWorkshops Proceedings

    International Nuclear Information System (INIS)

    Ramebaeck, H.; Straelberg, E.; Klemola, S.; Nielsen, Sven P.; Palsson, S.E.

    2012-01-01

    Due to a sparse interaction during the last years between practioners in gamma ray spectrometry in the Nordic countries, a NKS activity was started in 2009. This GammaSem was focused on seminars relevant to gamma spectrometry. A follow up seminar was held in 2010. As an outcome of these activities it was suggested that the 2011 meeting should be focused on practical issues, e.g. different corrections needed in gamma spectrometric measurements. This three day's meeting, GammaWorkshops, was held in September at Risoe-DTU. Experts on different topics relevant for gamma spectrometric measurements were invited to the GammaWorkshops. The topics included efficiency transfer, true coincidence summing corrections, self-attenuation corrections, measurement of natural radionuclides (natural decay series), combined measurement uncertainty calculations, and detection limits. These topics covered both lectures and practical sessions. The practical sessions included demonstrations of tools for e.g. corrections and calculations of the above meantioned topics. (Author)

  9. GammaWorkshops Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramebaeck, H. (ed.) (Swedish Defence Research Agency (Sweden)); Straalberg, E. (Institute for Energy Technology, Kjeller (Norway)); Klemola, S. (Radiation and Nuclear Safety Authority, STUK (Finland)); Nielsen, Sven P. (Technical Univ. of Denmark. Risoe National Lab. for Sustainable Energy, Roskilde (Denmark)); Palsson, S.E. (Icelandic Radiation Safety Authority (Iceland))

    2012-01-15

    Due to a sparse interaction during the last years between practioners in gamma ray spectrometry in the Nordic countries, a NKS activity was started in 2009. This GammaSem was focused on seminars relevant to gamma spectrometry. A follow up seminar was held in 2010. As an outcome of these activities it was suggested that the 2011 meeting should be focused on practical issues, e.g. different corrections needed in gamma spectrometric measurements. This three day's meeting, GammaWorkshops, was held in September at Risoe-DTU. Experts on different topics relevant for gamma spectrometric measurements were invited to the GammaWorkshops. The topics included efficiency transfer, true coincidence summing corrections, self-attenuation corrections, measurement of natural radionuclides (natural decay series), combined measurement uncertainty calculations, and detection limits. These topics covered both lectures and practical sessions. The practical sessions included demonstrations of tools for e.g. corrections and calculations of the above meantioned topics. (Author)

  10. Airborne gamma-ray spectrometry

    DEFF Research Database (Denmark)

    Hovgaard, Jens

    A new method - Noise Adjusted Singular Value Decomposition, NASVD - for processing gamma-ray spectra has been developed as part of a Ph.D. project. By using this technique one is able to decompose a large set of data - for example from airborne gamma-ray surveys - into a few spectral components....... By knowing the spectral components and their amplitudes in each of the measured spectra one is able to extract more information from the data than possible with the methods used otherwise....

  11. Methodology for determination of activity of radionuclides by gamma spectrometry; Metodologia para determinacao da atividade de radionuclideos por sistema de espectrometria gama

    Energy Technology Data Exchange (ETDEWEB)

    Fragoso, Maria da Conceicao de Farias; Oliveira, Victor Rogerio S. de; Oliveira, Mercia L.; Lima, Fernando Roberto de Andrade, E-mail: mariacc05@gmail.com [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-NE), Recife, PE (Brazil)

    2014-07-01

    Due to the growth in the number of procedures that make use of the positron emission tomography (PET), there is a need for standard solutions for the calibration of the systems used for the measurement of the PET radiopharmaceutical (activimeter) in radiopharmacies and in nuclear medicine services. Among the existing alternatives for the standardization of radioactive sources, the method known as gamma spectrometry is widely used for short-lived radionuclides. The purpose of this study was to implement the methodology for standardization of the {sup 18}F solutions by gamma spectrometry at the Regional Center for Nuclear Sciences of the Northeast (CRCN-NE/CNEN-NE), Brazil. (author)

  12. Fission products control by gamma spectrometry in purex process solutions

    International Nuclear Information System (INIS)

    Goncalves, Maria Augusta

    1982-01-01

    This paper deals with a radiometric method for fission products analysisby gamma spectrometry. This method will be applied for fission productscontrol at the irradiated material processing facility, under construction inthe Instituto de Pesquisas Energeticas e Nucleares, SP, Brazil. Countinggeometry was defined taking into account the activities of process solutionsto be analysed, the remotely operated aliquotation device of analytical celland the available detection system. Natural and 19,91% enriched uraniumsamples were irradiated at IEAR-1 reactor in order to simulate thecomposition of Purex process solutions. After a short decay time, the sampleswere dissolved with HNO 3 and then, conditioned in standard flasks withdefined geometry. The spectra were obtained by a Ge(Li) semiconductordetector and analysed by the GELIGAM software system, losing a floppy-diskconnected to a PDP-11/05 computer. Libraries were prepared and calibrationswere made with standard sources to fit the programs to the analysis offission products in irradiated uranium solutions. It was possible to choosethe best program to be used in routine analysis with the obtained data.(author)

  13. Comparison of the analytical methods used to determine natural and artificial radionuclides from environmental samples by gamma, alpha and beta spectrometry

    DEFF Research Database (Denmark)

    Pöllänen, Roy; Virtanen, Sinikka; Kämäräinen, Meerit

    In CAMNAR, an extensive interlaboratory exercise on the analytical methods used to determine several radionuclides present in the environmental samples was organized. Activity concentration of different natural radionuclides, such as Rn-222, Pb-210, Po-210, K-40, Ra-226, Ra-228 and isotopes...... of uranium, in addition to artificial Cs-137 and Am-241 were analysed from lake sediment samples and drinking water. The measurement techniques were gamma-ray spectrometry, alpha spectrometry, liquid scintillation counting and inductively coupled plasma mass spectrometry. Twenty six laboratories from nine...

  14. Comparison of in situ gamma soil analysis and soil sampling data for mapping 241Am and 239Pu soil concentrations at the Nevada Test Site

    International Nuclear Information System (INIS)

    Kirby, J.A.; Anspaugh, L.R.; Phelps, P.L.; Huckabay, G.W.; Markwell, F.; Barnes, M.

    1976-01-01

    Soil sampling and in situ 241 Am-gamma counting with an array of four high purity, planar, Ge detectors are compared as means of determining soil concentration contours of plutonium and their associated uncertainties. Results of this survey, which covered an area of approximately 300,000 m 2 , indicate that with one-third the number of sampling locations, the in situ gamma survey provided soil concentration contours with confidence intervals that were about one-third as wide as those obtained with soil sampling. The methods of the survey are described and a discussion of advantages and limitations of both methods is given

  15. Comparison of in situ gamma soil analysis and soil sampling data for mapping 241Am and 239Pu soil concentrations at the Nevada Test Site

    International Nuclear Information System (INIS)

    Kirby, J.A.; Anspaugh, L.R.; Phelps, P.L.; Huckabay, G.W.; Markwell, F.R.; Barnes, M.G.

    1977-01-01

    Soil sampling and in situ 241 Am-gamma counting with an array of four high-purity, planar, Ge detectors are compared as means of determining soil concentration contours of plutonium and their associated uncertainties. Results of this survey, which covered an area of approximately 300,000 m 2 , indicate that with one-third the number of sampling locations, the in situ gamma survey provided soil concentration contours with confidence intervals that were about one-third as wide as those obtained with soil sampling. The methods of the survey are described and a discussion of advantages and limitations of both methods is given

  16. Gamma spectrometry for chronology of recent sediments

    Energy Technology Data Exchange (ETDEWEB)

    Pittauerova, Daniela

    2013-12-17

    This thesis deals with several aspects of gamma spectrometric analysis of natural and artificial isotopes in sediments and their use as tracers for qualification and quantification of accumulation and mixing processes in different aquatic environments. Sediment cores from three distinct areas including terrigenous sediments deposited on the continental slope off NW Africa, deep sea sediments off Sumba Island and five stations from the Gulf of Eilat in the Red Sea area were measured and interpreted within this dissertation. The main concern in gamma spectrometry of voluminous environmental samples is a reliable efficiency calibration. This is specially relevant for the analysis of low energy gamma emitters (<100 keV). {sup 210}Pb, an important isotopic tracer to cover the period of the last century, is one of them. Within this work mathematical efficiency calibration was applied using a commercial software package. A series of validation tests was performed and evaluated for point and voluminous samples. When using {sup 210}Pb as a tracer it is necessary to determine its excess portion, which is not supported by ingrowth from the parent nuclide {sup 226}Ra. Its analysis is mostly performed via short lived daughter isotopes that follow after the intermediate gaseous member {sup 222}Rn. Preventing the escape of radon from the sample is a critical step before analysis due to a negative effect of supported {sup 210}Pb underestimation on the chronology, which was also documented in this thesis. Time series registering ingrowth of {sup 214}Pb and {sup 214}Bi towards radioactive equilibrium with {sup 226}Ra in different containers were evaluated for analyses of {sup 226}Ra. Direct analyses of {sup 226}Ra was compared to its detection via daughter products. A method for aligning parallel radionuclide depth profiles was described and applied successfully in two case studies from the continental slope off NW Africa and off Sumba Island, Indonesia. This is primarily important

  17. Gamma Spectrometry Analysis of Different Brands of Cement used in Nigeria

    International Nuclear Information System (INIS)

    Olarinoye, I.O.; Baba-Kutigi, A.N.; Sharifat, I.; Kolo, M.T.

    2014-01-01

    The natural radionuclide content of common brands of cement consumed in Nigeria is presented in this work. Samples of 9 brands of grey ordinary Portland cement (OPC) and 5 brands of white cement were collected and analyzed for their radiological content by gamma spectrometry using a 7.6 x 7.6 NaI(TI) detector. The total average content of 226 Ra, 232 Th and 40 k for all the cement brand samples were 38.1, 27.9 and 301.1 Bq/kg respectively and are lower when compared to the world average (50, 50 and 500 Bq/Kg) in building materials. The evaluated radium equivalent activities, external and internal indices were lower than the recommended safe limit and are comparable with result from similar studies concluded in other countries. The evaluation mean gonadal dose of equivalents of two cement brand samples were found to be higher than the world average in soil while others are less than the world average in soil.

  18. Determination of vanadium in titanate-based ferroelectrics by INAA with discriminating gamma-ray spectrometry

    Czech Academy of Sciences Publication Activity Database

    Kameník, Jan; Dragounová, K.; Kučera, Jan; Bryknar, Z.; Trepakov, Vladimír; Strunga, Vladimír

    2017-01-01

    Roč. 311, č. 2 (2017), s. 1333-1338 ISSN 0236-5731. [1st International Conference on Radioanalytical and Nuclear chemistry (RANC). Budapest, 10.04.2016-15.04.2016] R&D Projects: GA ČR(CZ) GBP108/12/G108; GA MŠk LM2015056 Institutional support: RVO:68378271 ; RVO:61389005 Keywords : Titanate-based ferroelectrics * Vanadium * INAA * discriminating gamma-ray spectrometry Subject RIV: CB - Analytical Chemistry, Separation; BM - Solid Matter Physics ; Magnetism (FZU-D) OBOR OECD: Analytical chemistry; Condensed matter physics (including formerly solid state physics, supercond.) (FZU-D) Impact factor: 1.282, year: 2016

  19. Gamma spectrometry on MANITU 271-01 gamma scan wires

    International Nuclear Information System (INIS)

    Dassel, G.; Buurveld, H.A.; Minkema, J.

    1994-08-01

    A series of irradiation experiments (271-series) is being performed of the sustain programme for material development and characterization of the NET (Next European Torus). In the framework of the first irradiation experiment 271-01, with irradiation up to 0.2 dpa, four gamma scan wires have been examined by gamma scanning. The purpose of the gamma scan wires (GSW) is to get information about the neutron fluence distribution in the capsules during irradiation. In the stainless steel wires the nuclides Co-58, Mu-54, Fe-59 and Co-60 are produced, are characteristic for fast and thermal neutron reactions. (orig./HP)

  20. A self-sufficient and general method for self-absorption correction in gamma-ray spectrometry using GEANT4

    International Nuclear Information System (INIS)

    Hurtado, S.; Villa, M.; Manjon, G.; Garcia-Tenorio, R.

    2007-01-01

    This paper presents a self-sufficient and general method for measurement of the activity of low-level gamma-emitters in voluminous samples by gamma-ray spectrometry with a coaxial germanium detector. Due to self-absorption within the sample, the full-energy peak efficiency of low-energy emitters in semiconductor gamma-spectrometers depends strongly on a number of factors including sample composition, density, sample size and gamma-ray energy. As long as those commented factors are well characterized, the influence of self-absorption in the full-energy peak efficiency of low-energy emitters can be calculated using Monte Carlo method based on GEANT4 code for each individual sample. However this task is quite tedious and time consuming. In this paper, we propose an alternative method to determine this influence for voluminous samples of unknown composition. Our method combines both transmission measurements and Monte Carlo simulations, avoiding the application of Monte Carlo full-energy peak efficiency determinations for each individual sample. To test the accuracy and precision of the proposed method, we have calculated 210 Pb activity in sediments samples from an estuary located in the vicinity of several phosphates factories with the proposed method, comparing the obtained results with the ones determined in the same samples using two alternative radiometric techniques

  1. Calculation of “LS-curves” for coincidence summing corrections in gamma ray spectrometry

    Science.gov (United States)

    Vidmar, Tim; Korun, Matjaž

    2006-01-01

    When coincidence summing correction factors for extended samples are calculated in gamma-ray spectrometry from full-energy-peak and total efficiencies, their variation over the sample volume needs to be considered. In other words, the correction factors cannot be computed as if the sample were a point source. A method developed by Blaauw and Gelsema takes the variation of the efficiencies over the sample volume into account. It introduces the so-called LS-curve in the calibration procedure and only requires the preparation of a single standard for each sample geometry. We propose to replace the standard preparation by calculation and we show that the LS-curves resulting from our method yield coincidence summing correction factors that are consistent with the LS values obtained from experimental data.

  2. Study of the parabolic-spherical shape on the energy resolution in gamma spectrometry

    International Nuclear Information System (INIS)

    Silva, Joao Carlos Pereira da

    1997-01-01

    In gamma spectrometry, the energy resolution is an important parameter. This parameter measures the capability of the system to separate two photopeaks that are together. Scintillation systems have various factors that affect the energy resolution: energy deposition, light emission, light collection and electric signal processing. Light collection depended on the mechanisms of light transport until light strikes on the photocathode. In this trajectory the light losses energy by attenuation and refractions on the surfaces. In order to minimize these effects, a parabolic-spherical shape is proposed. The energy resolutions of hemispherical and parabolic-spherical shapes were measured. The results show a better resolution for the new shape, about 33% for Compton edge due to a 137 Cs radioactive source. (author)

  3. Recent advances in matrix-assisted laser desorption/ionisation mass spectrometry imaging (MALDI-MSI) for in situ analysis of endogenous molecules in plants.

    Science.gov (United States)

    Qin, Liang; Zhang, Yawen; Liu, Yaqin; He, Huixin; Han, Manman; Li, Yanyan; Zeng, Maomao; Wang, Xiaodong

    2018-04-17

    Mass spectrometry imaging (MSI) as a label-free and powerful imaging technique enables in situ evaluation of a tissue metabolome and/or proteome, becoming increasingly popular in the detection of plant endogenous molecules. The characterization of structure and spatial information of endogenous molecules in plants are both very important aspects to better understand the physiological mechanism of plant organism. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) is a commonly-used tissue imaging technique, which requires matrix to assist in situ detection of a variety of molecules on the surface of a tissue section. In previous studies, MALDI-MSI was mostly used for the detection of molecules from animal tissue sections, compared to plant samples due to cell structural limitations, such as plant cuticles, epicuticular waxes, and cell walls. Despite the enormous progress that has been made in tissue imaging, there is still a challenge for MALDI-MSI suitable for the imaging of endogenous compounds in plants. This review summarises the recent advances in MALDI-MSI, focusing on the application of in situ detection of endogenous molecules in different plant organs, i.e. root, stem, leaf, flower, fruit, and seed. Further improvements on instrumentation sensitivity, matrix selection, image processing and sample preparation will expand the application of MALDI-MSI in plant research. Copyright © 2018 John Wiley & Sons, Ltd.

  4. Technology information profile: RL321103 -- In situ gamma spectrometer

    International Nuclear Information System (INIS)

    Schilk, A.J.

    1993-11-01

    Past operations of uranium production and support facilities at several Department of Energy (DOE) sites have occasionally resulted in the local contamination of some surface and subsurface soils. Such contamination commonly occurs within waste burial sites, cribs, pond bottom sediments, and areas surrounding waste tanks or uranium scrap, ore, tailing, and slag heaps. The thorough cleanup of these sites is a major public concern and a high priority for the DOE, but before any effective remedial protocols can be established, the three-dimensional distributions of the uranium contaminants must be adequately characterized. Unfortunately, traditional means of obtaining soil activities (e.g., grab sampling followed by laboratory analyses) are notoriously cumbersome, expensive, time-consuming, and often non-representative when very large areas are being surveyed. Hence, new technologies must be developed, or existing ones improved, to allow for the cheaper, better, faster (i.e., real-time) and safer characterization of uranium concentrations at these critical sites. The primary objective for this program is to develop, construct, and field/pilot test the in situ gamma spectrometer for the rapid measurement of uranium in surface and shallow subsurface soils at the Fernald site in Ohio

  5. Gamma-ray spectrometry combined with acceptable knowledge (GSAK). A technique for characterization of certain remote-handled transuranic (RH-TRU) wastes. Part 1. Methodology and techniques

    International Nuclear Information System (INIS)

    Hartwell, J.K.; McIlwain, M.E.

    2005-01-01

    Gamma-ray spectrometry combined with acceptable knowledge (GSAK) is a technique for the characterization of certain remote-handled transuranic (RH-TRU) wastes. GSAK uses gamma-ray spectrometry to quantify a portion of the fission product inventory of RH-TRU wastes. These fission product results are then coupled with calculated inventories derived from acceptable process knowledge to characterize the radionuclide content of the assayed wastes. GSAK has been evaluated and tested through several test exercises. GSAK approach is described, while test results are presented in Part II. (author)

  6. Medium-resolution autonomous in situ gamma detection system for marine and coastal waters

    International Nuclear Information System (INIS)

    Schwantes, J.M.; Addleman, R.S.; Davidson, J.D.; Douglas, M.; Meier, D.; Mullen, O.D.; Myjak, M.; Jones, M.E.; Woodring, M.L.; Johnson, B.; Santschi, P.H.

    2009-01-01

    We are developing a medium-resolution autonomous in situ gamma detection system for marine and coastal waters. The system is designed to extract and preconcentrate isotopes of interest from natural waters prior to detection in order to eliminate signal attenuation of the gamma rays traveling through water and lower the overall background from the presence of naturally occurring radioactive isotopes ( 40 K and U-Th series radionuclides). Filtration is used to preconcentrate target isotopes residing on suspended particles, while chemosorption is employed to preferentially extract truly dissolved components from the water column. Used filter and chemosorbent media will be counted autonomously using two LaBr 3 detectors in a near 4-π configuration around the samples. A compact digital pulse processing system, developed in-house and capable of running in coincidence mode, is used to process the signal from the detectors to a small on-board computer. The entire system is extremely compact (9' dia. x 30' len.) and platform independent, but designed for initial deployment on a research buoy. A variety of commercial and in-house nano-porous chemosorbents have been selected, procured or produced, and these and filter and detector components have been tested. (author)

  7. European coordination of environmental airborne gamma ray spectrometry. Final report 1999

    International Nuclear Information System (INIS)

    Sanderson, D.C.; McLeod, J.J.

    1999-04-01

    This Concerted Action was funded under the EURATOM Nuclear Fission Safety Programme of the Fourth Framework Programme, and was initiated to address transnational issues relating to environmental airborne gamma ray spectrometry (AGS). Significant development of AGS systems and teams has taken place within Europe during the period following the Chernobyl accident. The technique is increasingly recognised as particularly relevant to emergency response. It is also uniquely capable of acquiring data on anthropogenic and natural radionuclides on regional, national and international scales, for reference purposes, ecological studies and epidemiological research. Prior to this EU programme the methodologies and systems used by European AGS teams had undergone rapid and largely uncoordinated development. This raised questions about comparability of systems, applications, and data between teams, duplication of research, the scope for transnational cooperation and standardisation, and future research and development needs in the field. This project, which brought together ten AGS teams from across Europe, was formed to address these issues. The work was conducted in three stages and has largely succeeded in its objectives. An active communication network was developed for collaboration and exchange of information, and to start the process of harmonisation of the different methodologies used by individual AGS teams. Two formal partners' meetings were organised, the first aimed at defining the EU capability in AGS, the second, in the form of an international symposium (RADMAGS), was aimed at reviewing developments on future research needs and the scope for standardisation. This report gives full details of the project and its deliverables together with discussion of the further needs in support of transnational harmonisation of this topic. The European Capability for AGS was defined at an early stage of the project, and monitored throughout. An EU Bibliography on AGS

  8. Determination of U, Th and K in bricks by gamma -ray spectrometry, X-ray fluorescence analysis and neutron activation analysis

    Czech Academy of Sciences Publication Activity Database

    Bártová, H.; Kučera, Jan; Musílek, L.; Trojek, T.; Gregorová, E.

    2017-01-01

    Roč. 140, NOV (2017), s. 161-166 ISSN 0969-806X R&D Projects: GA MŠk LM2015056 Institutional support: RVO:61389005 Keywords : Gamma-ray spectrometry * neutron activation analysis * environmental dosimetry Subject RIV: CB - Analytical Chemistry , Separation OBOR OECD: Analytical chemistry Impact factor: 1.315, year: 2016

  9. Integrated evaluation of the geology, aero gamma spectrometry and aero magnetometry of the Sul-Riograndense Shield, southernmost Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Leo A.; Savian, Jairo F., E-mail: leo.hartmann@ufrgs.br [Universidade Federal do Rio Grande do Sul (UFRS), Porto Alegre, RS (Brazil). Instituto de Geociencias; Lopes, William R. [Servico Geologico do Brasil (CPRM), Porto Alegre, RS (Brazil). Gerencia de Geologia e Mineracao

    2016-03-15

    An integrated evaluation of geology, aero gamma spectrometry and aero magnetometry of the Sul-Riograndense Shield is permitted by the advanced stage of understanding of the geology and geochronology of the southern Brazilian Shield and a 2010 airborne geophysical survey. Gamma rays are registered from the rocks near the surface and thus describe the distribution of major units in the shield, such as the Pelotas batholith, the juvenile São Gabriel terrane, the granulite-amphibolite facies Taquarembo terrane and the numerous granite intrusions in the foreland. Major structures are also observed, e.g., the Dorsal de Cangucu shear. Magnetic signals register near surface crustal compositions (analytic signal) and total crust composition (total magnetic signal), so their variation as measured indicates either shallow or whole crustal structures. The Cacapava shear is outstanding on the images as is the magnetic low along the N-S central portion of the shield. These integrated observations lead to the deepening of the understanding of the largest and even detailed structures of the Sul-Riograndense Shield, some to be correlated to field geology in future studies. Most significant is the presence of different provinces and their limits depending on the method used for data acquisition - geology, aero gamma spectrometry or aero magnetometry. (author)

  10. Corrosion behaviour of selected high-level waste packaging materials under gamma irradiation and in-situ disposal conditions in rock salt

    International Nuclear Information System (INIS)

    Smailos, E.; Schwarzkopf, W.; Koester, R.

    1988-07-01

    Corrosion studies performed until now on a number of materials have shown that unalloyed steels, Hastelloy C4 and Ti 99.8-Pd are the most promising materials for a long-term resistant packaging to be used in high-level waste (HLW) canister disposal in rock salt formations. To characterize their corrosion behaviour in more detail, additional studies have been performed. The influence has been examined which is exerted by the gamma dose rate (1 Gy/h to 100 Gy/h) on the corrosion of three preselected steels and Hastelloy C4 at 90 0 C in a salt brine (Q-brine) rich in MgCl 2 , i.e., conditions relevant to accident scenarios in a repository. In addition, in-situ corrosion experiments have been carried out in the Asse salt mine at elevated temperatures (120 0 C to 210 0 C) in the absence and in the presence of a gamma radiation field of 3 x 10 2 Gy/h, within the framework of the German/US Brine Migration Test. Under the test conditions the gamma radiation did not exert a significant influence on the corrosion of the steels investigated, whereas Hastelloy C4, exposed to dose rates of 10 Gy/h and 100 Gy/h, underwent pitting and crevice corrosion (20 μm/a at the maximum).The low amounts of migrated salt brine (140 ml after 900 days) in the in-situ- experiment did not produce noticeable corrosion of the materials. (orig./RB) [de

  11. Gamma-ray spectrometry combined with acceptable knowledge (GSAK). A technique for characterization of certain remote-handled transuranic (RH-TRU) wastes. Part 2. Testing and results

    International Nuclear Information System (INIS)

    Hartwell, J.K.; McIlwain, M.E.

    2005-01-01

    Gamma-ray spectrometry combined with acceptable knowledge (GSAK) is a technique for the characterization of certain remote-handled transuranic (RH-TRU) wastes. GSAK uses gamma-ray spectrometry to quantify a portion of the fission product inventory of RH-TRU wastes. These fission product results are then coupled with calculated inventories derived from acceptable process knowledge to characterize the radionuclide content of the assayed wastes. GSAK has been evaluated and tested through several test exercises. These tests and their results are described; while the former paper in this issue presents the methodology, equipment and techniques. (author)

  12. Development of high sensitivity gamma and beta sensors for in situ diffusion tests in the mudstone in France

    International Nuclear Information System (INIS)

    Lin, Zhenhua

    2017-01-01

    The precise monitoring of radiotracers, for example used for medical imaging, for the storage of ultimate waste, or for certain industrial applications can be a very complex subject. The development of low-noise sensors with long-term stability and high geometric flexibility were engaged by the AXINT company. (Hautefeuille, et al., 2006). My PhD thesis was focused on experiments in the diffusion of radiotracers, typically to monitor the possible leakage of radioactive products from the geological repositories. We focuses on the study of the "2"2Na and "3"6Cl ion diffusion, which is one of the highest cation and anions diffusion rate in geological medium, as well as actinides, which represent the majority of the radioactive elements of Stored nuclear waste. This thesis is in continuity with the research carried out by ANDRA (National Agency for Radioactive Waste), under contract with the laboratory ILM (Institute Light Matter), of which AXINT is the main subcontractor. The present project describes the research work that foreseen the radiation impact on the environment for the coming years during the deep disposal of nuclear waste. Our work focus on the investigation and quantification of the radionuclide diffusion through the geological clay barriers. A new in situ experiment was considered by Andra for the study of the radionuclide migration. Compared to previous experiments, this new in situ diffusion test required longer distance (hundreds of mm), longer time-scale (over 10 years), and real time in situ monitoring of radionuclides migration. To fulfill these conditions, the work was organized as following: 1: Conception and dimensional design of the Diffusion of Radio Nuclide (DRN) experiments in solving emission of beta and gamma radiations 2: Development of corresponding beta and gamma monitoring systems by means of sensors located in peripheral boreholes. (author) [fr

  13. Determination of low-level Radium isotope activities in fresh waters by gamma spectrometry

    International Nuclear Information System (INIS)

    Molina Porras, Arnold; Condomines, Michel; Seidel, Jean Luc

    2017-01-01

    A new portable sampling system was developed to extract Radium isotopes from large volumes (up to 300 L) of fresh surface- and ground-waters of low Ra-activities (<5 mBq/L). Ra is quantitatively adsorbed on a small amount (6.5 g) of MnO_2-coated acrylic fibers, which are then dried and burned at 600 °C in the laboratory. The resulting Mn-oxide powder (about 2 cm"3 when compacted) is then analyzed through gamma-ray spectrometry which allows measurement of the whole Ra quartet ("2"2"6Ra, "2"2"8Ra, "2"2"4Ra and "2"2"3Ra) in a single counting of a few days. The usual relative standard combined uncertainties (1σ) are 2–3% for "2"2"6Ra, "2"2"8Ra and "2"2"4Ra; and less than 10% for "2"2"3Ra. This method was applied to the analysis of Ra in karstic waters of the Lez aquifer, and surface- and ground-waters of the upper and middle Vidourle watershed (South of France). The analyzed waters have relatively low "2"2"6Ra activities (1–4 mBq/L) in both cases, regardless of the contrasted geology (Mesozoic limestone vs crystalline Variscan basement), but clearly distinct ("2"2"8Ra/"2"2"6Ra) ratios in agreement with the differences in Th/U ratios of the two drained areas. Short-lived Ra isotopes ("2"2"4Ra and "2"2"3Ra) appear to be mainly influenced by near-surface desorption/recoil processes for most of the sampling sites. - Highlights: • New portable system for sampling fresh- and ground-waters of low Ra activities. • Simultaneous measurement of all four radium isotopes through gamma-spectrometry. • Relative uncertainties are 2% to 3% for "2"2"6Ra, "2"2"8Ra and "2"2"4Ra; and <10 % for "2"2"3Ra. • ("2"2"8Ra/"2"2"6Ra) ratios are valuable tracers of water origin in karstic aquifers.

  14. Use of Airborne Gamma-Ray Spectrometry in case of emergency. Example of HELGA exercise - collaboration between France and Germany

    International Nuclear Information System (INIS)

    Guillot, L.

    2004-01-01

    Since Chernobyl accident, airborne gamma-ray spectrometry has been recognised as a useful tool to evaluate consequences of an accident over large areas. Nine European countries have capabilities to perform such measurements. Between 1996 and 2003, a collaboration between these teams was supported by European community. In 2002, an exercise involving airborne and ground-based measurements was organised in Scotland. This exercise demonstrated the ability of European countries to provide assistance to one of them in case of emergency. Since this project has been completed, the French and German team decided to continue a collaboration. The CEA team (France) went in Germany in 2003 to participate to a survey with the German team. In September 2004, an exercise including mapping of contaminated areas and orphan sources search is planned in France. Such actions are good opportunities to exchange technical information about the acquisition systems and operating procedures. It is also essential to improve the availability of teams to obtain comparable and compatible results. The AGRS (airborne gamma ray spectrometry) systems involved in this exercise will be described and compared in this paper. The capacity of teams to work in collaboration in various situation (orphan source search, contamination mapping) will be then evaluated. In particular, a European Radiometric and Spectrometry format defined during Eccomags project will be used to create a database of raw and processed data. The aim is to produce quickly composite maps with data recorded by different teams. A choice of results will be presented and an assessment of capability of teams to work in collaboration will be done. (author)

  15. Gamma-ray spectrometry of granitic suites of the Paranaguá Terrane, Southern Brazil

    Science.gov (United States)

    Weihermann, Jessica Derkacz; Ferreira, Francisco José Fonseca; Cury, Leonardo Fadel; da Silveira, Claudinei Taborda

    2016-09-01

    The Paranaguá Terrane, located in the coastal portion of the states of Santa Catarina, Paraná and São Paulo in Southern Brazil is a crustal segment constituted mainly by an igneous complex, with a variety of granitic rocks inserted into the Serra do Mar ridge. The average altitude is approximately 1200 m above sea level, with peaks of up to 1800 m. Due to the difficulty of accessing the area, a shortage of outcrops and the thick weathering mantle, this terrane is understudied. This research aims to evaluate the gamma-ray spectrometry data of the granitic suites of the Paranaguá Terrane, in correspondence with the geological, petrographical, lithogeochemical, relief and mass movement information available in the literature. Aerogeophysical data were acquired along north-south lines spaced at 500 m, with a mean terrain clearance of 100 m. These data cover potassium (K, %), equivalent in thorium (eTh, ppm) and equivalent in uranium (eU, ppm). After performing a critical analysis of the data, basic (K, eU, eTh) and ternary (R-K/G-eTh/B-eU) maps were generated and then superimposed on the digital elevation model (DEM). The investigation of the radionuclide mobility across the relief and weathering mantle consisted of an analysis of the schematic profiles of elevation related with each radionuclide; a comparison of the K, eU and eTh maps with their 3D correspondents; and the study of mass movements registered in the region. A statistical comparison of lithogeochemical (K, U, Th) and geophysical (K, eU, eTh) data showed consistency in all the granitic suites studied (Morro Inglês, Rio do Poço and Canavieiras-Estrela). Through gamma-ray spectrometry, it was possible to establish relationships between scars (from mass movements) and the gamma-ray responses as well as the radionuclide mobility and the relief and to map the granitic bodies.

  16. Experimental determination of nuclear reaction rates (n,γ) by the gamma-rays capture spectrometry technique

    International Nuclear Information System (INIS)

    Lucatero, M.A.

    1976-01-01

    The technique of the gamma-rays capture spectrometry was used in the experimental determination of nuclear reaction rates of the type (n,γ). This technique consists in the incidence of a thermal neutrons collimated beam upon a sample, detecting the capture spectrum of gamma rays emitted at a solid fixed angle. In the determination of the efficiency curve intrinsic to the detection electronic system the reactions 199 Hg(n,γ) 200 Hg, 56 Fe(n,γ) 57 Fe and 63 Cu(n,γ) 64 Cu were used with the energy of the gamma rays capture of 5.976, 7.635 and 7.915 Mev respectively, through the irradiation of standard samples of Hg(175.3g), Fe(110.4g) and Cu(108.5g) of cylindrical geometry the two former and parallelepiped the latter. The problem concerning the corrections due to the thermal neutrons flux depression, the gammas auto-attenuation, and the geometric factor due to the cylindrical and parallelepiped geometry are involved in the data process. The experimental determination of the reaction 35 Cl(n,γ) 36 Cl rate was made through the observation of the gamma caputre of 6.111 Mev when a sample of CaCl 2 of cylindrical geometry was irradiated. This rate can be favorably compared with the reaction rate determined theoretically. (author)

  17. Characterization of three digital signal processor systems used in gamma ray spectrometry

    International Nuclear Information System (INIS)

    Reguigui, N.; Morel, J.; Ben Kraiem, H.; Mahjoub, A.

    2002-01-01

    Various manufacturers have recently introduced digital signal processing systems that allow data acquisition in gamma spectrometry at high-input counting rates (several thousand pulses per second). In these systems, the signal digitization is performed immediately following the preamplification stage. This allows digital shaping and filtering of the signal which increases the number of possible combinations in signal shaping and as a consequence, optimizes the resolution as a function of the detector characteristics and the counting rate. Basic characteristic parameters of three digital signal processors that were recently introduced in the market have been studied and compared to those of an analog system. This study is carried out using a hyper-pure coaxial type germanium detector and 57 Co, 60 Co and 137 Cs radioactive sources. Performance parameters such as energy resolution, system throughput, and counting losses that are due to dead time and pile-up effects are presented and discussed

  18. Decision Threshold and Detection Limit in Spectrometric Measurements. Part 1: Application to Gamma Spectrometry; Umbral de Decision y Limite de Deteccion en Medidas Espectrometricas. Parte 1: Aplicacion a la Espectrometria Gamma

    Energy Technology Data Exchange (ETDEWEB)

    Perez, C.; Gasco, C.; Lopez, M.A.

    2010-03-03

    This report summarised the author's lecture of the advanced gamma spectrometry course organised by CIEMAT. The characteristic limits determination in gamma spectrometry generally is obtained through the programming that the trade marks offers to the client with the objective of the automatic calculation of the activity concentrations existing in a sample. In this report, the examples shown in the ISO 11929 standard are compared to the programming realised by Genie 2k for determining characteristic limits. The main difference of both is located in the uncertainty calculations due to the efficiency calibration that is considered by ISO and not by Genie 2K. Through implementation in the software developed by trade marks will be possible to introduce this uncertainty and to assimilate to the calculation done by ISO 11929. In the second part of this report will be analyzed the more complicated samples of this application as counting in a whole body counter (following ISO-28218 about Performance Criteria for radio bioassay), multiplet, overlapping, addition of several peaks for obtaining the activity concentration, etc. (Author) 19 refs.

  19. Validation of Am-241 measurement in ion chamber type smoke detector by using gamma spectrometry system

    International Nuclear Information System (INIS)

    Yii Mei Wo; Khairul Nizam Razali

    2005-01-01

    Smoke detectors are useful devices in modern days that able to save many lives. Even though, the use of ion chamber type smoke detector (usually contain Americium-241) was exempted in Malaysia, but the trading of this device was controlled by regulation, under the Atomic Energy Licensing Act (Act 304). The activity of the Am-241 can be measured by using the Gamma Spectrometry System since it was much easier, compared to Alpha Spectrometry System. To do so, the system was first need to be calibrated using the standard reference source to find the efficiency of the germanium detector. The method used for the measurement was first validated for several relevant parameters, which include specificity, precision (repeatability), bias (accuracy), linearity, working range, detection limit, robustness and ruggedness to ensure it was fit for the purpose. The measured Am-241 activity inside the smoke detector will be reported together with a reasonable expanded uncertainty arise from the measurement. (Author)

  20. Simple circuit for precise measurement of live dead or clock time in gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Hammer, W.; Sterlinski, S.

    1976-01-01

    The basic design features and characteristics of circuit are described in the paper. The circuit coupled to a multichannel analyser (MCA) enables one of times: live(Tsub(iota)), dead (Tsub(d)) or clock(Tsub(c)) to be measured precisely. Second one is measured by a built-in timer of MCA. Having the Tsub(c)/Tsub(iota) ratio and utilizing suitable mathematical formulas one can make the corrections for both main effects (dead-time and pile-up) which yield counting losses in gamma-ray spectrometry at high and/or variable activities. Two examples of the dead-time and pile-up corrections by using the new circuit are presented in this paper. (author)

  1. GammaLog Playback 1.0 - mobile gamma ray spectrometry software

    International Nuclear Information System (INIS)

    Watson, R.J.; Smethurst, M.A.

    2011-01-01

    The Geological Survey of Norway (NGU) operates a mobile gamma ray spectrometer system which can be used in nuclear emergency situations to determine the location and type of orphan sources, or the extent and type of fallout contamination. The system consists of a 20 litre (16 litre downward and 4 litre upward looking) RSX-5 NaI detector and spectrometer, and can be mounted in fixed wing aircraft, helicopters, or vans/cars as appropriate. NGU has developed its own data acquisition and analysis software for this system. GammaLog (Smethurst 2005) controls the acquisition, display, and storage of data from the spectrometer, and performs real-time data analysis including estimation of dose rates and fallout concentrations, and separation of geological and anthropogenic components of the signal. The latter is particularly important where the geological radioisotope signal varies strongly from one place to another, and makes it easier to locate and identify anthropogenic sources which might otherwise be difficult to separate from the geological background signal. A modified version of GammaLog has been developed, GammaLog Playback, which allows the replay of previously acquired GammaLog datasets, while performing similar processing and display as the GammaLog acquisition software. This allows datasets to be reviewed and compared in the field or during post-survey analysis to help plan subsequent measurement strategies.(Au)

  2. Determination of 228Th, 226Ra and 40K in Soil Using In-Situ GammaSpectrometer

    International Nuclear Information System (INIS)

    Bunawas; Wahyudi; Syarbaini; Untara

    2000-01-01

    Determination of natural radionuclide in latosol soil at six locationsaround PPTN Serpong by using Inspector portable gamma spectrometer with highpurity Germanium detector (HPGe) which has 26% relative efficiency had beenobtained. Radionuclides data of 228 Th, 226 Ra and 40 K were obtained in4 hours, shorter than laboratories analysis which needed 3 weeks. Thedifferences between in-situ measurement and laboratory were 3.6% to 56.2% forsix conditions of soil measured. According to the specific activity dataanalysis using statistic hypothesis, the result shows that the activity of 228 Th and 226 Ra are independent on location, but 40 K is dependent onlocation. (author)

  3. Basics of Gamma Ray Detection

    Energy Technology Data Exchange (ETDEWEB)

    Stinnett, Jacob [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Venkataraman, Ram [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-09-13

    The objective of this training is to explain the origin of x-rays and gamma rays, gamma ray interactions with matter, detectors and electronics used in gamma ray-spectrometry, and features of a gamma-ray spectrum for nuclear material that is safeguarded.

  4. Efficiency transfer using the GEANT4 code of CERN for HPGe gamma spectrometry

    International Nuclear Information System (INIS)

    Chagren, S.; Tekaya, M.Ben; Reguigui, N.; Gharbi, F.

    2016-01-01

    In this work we apply the GEANT4 code of CERN to calculate the peak efficiency in High Pure Germanium (HPGe) gamma spectrometry using three different procedures. The first is a direct calculation. The second corresponds to the usual case of efficiency transfer between two different configurations at constant emission energy assuming a reference point detection configuration and the third, a new procedure, consists on the transfer of the peak efficiency between two detection configurations emitting the gamma ray in different energies assuming a “virtual” reference point detection configuration. No pre-optimization of the detector geometrical characteristics was performed before the transfer to test the ability of the efficiency transfer to reduce the effect of the ignorance on their real magnitude on the quality of the transferred efficiency. The obtained and measured efficiencies were found in good agreement for the two investigated methods of efficiency transfer. The obtained agreement proves that Monte Carlo method and especially the GEANT4 code constitute an efficient tool to obtain accurate detection efficiency values. The second investigated efficiency transfer procedure is useful to calibrate the HPGe gamma detector for any emission energy value for a voluminous source using one point source detection efficiency emitting in a different energy as a reference efficiency. The calculations preformed in this work were applied to the measurement exercise of the EUROMET428 project. A measurement exercise where an evaluation of the full energy peak efficiencies in the energy range 60–2000 keV for a typical coaxial p-type HpGe detector and several types of source configuration: point sources located at various distances from the detector and a cylindrical box containing three matrices was performed. - Highlights: • The GEANT4 code of CERN has been used to transfer the peak efficiency from point to points and voluminous detection configurations in HPGe gamma

  5. Laser Time-of-Flight Mass Spectrometry for Future In Situ Planetary Missions

    Science.gov (United States)

    Getty, S. A.; Brinckerhoff, W. B.; Cornish, T.; Ecelberger, S. A.; Li, X.; Floyd, M. A. Merrill; Chanover, N.; Uckert, K.; Voelz, D.; Xiao, X.; hide

    2012-01-01

    Laser desorption/ionization time-of-flight mass spectrometry (LD-TOF-MS) is a versatile, low-complexity instrument class that holds significant promise for future landed in situ planetary missions that emphasize compositional analysis of surface materials. Here we describe a 5kg-class instrument that is capable of detecting and analyzing a variety of analytes directly from rock or ice samples. Through laboratory studies of a suite of representative samples, we show that detection and analysis of key mineral composition, small organics, and particularly, higher molecular weight organics are well suited to this instrument design. A mass range exceeding 100,000 Da has recently been demonstrated. We describe recent efforts in instrument prototype development and future directions that will enhance our analytical capabilities targeting organic mixtures on primitive and icy bodies. We present results on a series of standards, simulated mixtures, and meteoritic samples.

  6. In-situ Isotopic Analysis at Nanoscale using Parallel Ion Electron Spectrometry: A Powerful New Paradigm for Correlative Microscopy

    Science.gov (United States)

    Yedra, Lluís; Eswara, Santhana; Dowsett, David; Wirtz, Tom

    2016-01-01

    Isotopic analysis is of paramount importance across the entire gamut of scientific research. To advance the frontiers of knowledge, a technique for nanoscale isotopic analysis is indispensable. Secondary Ion Mass Spectrometry (SIMS) is a well-established technique for analyzing isotopes, but its spatial-resolution is fundamentally limited. Transmission Electron Microscopy (TEM) is a well-known method for high-resolution imaging down to the atomic scale. However, isotopic analysis in TEM is not possible. Here, we introduce a powerful new paradigm for in-situ correlative microscopy called the Parallel Ion Electron Spectrometry by synergizing SIMS with TEM. We demonstrate this technique by distinguishing lithium carbonate nanoparticles according to the isotopic label of lithium, viz. 6Li and 7Li and imaging them at high-resolution by TEM, adding a new dimension to correlative microscopy. PMID:27350565

  7. International comparison of methods to test the validity of dead-time and pile-up corrections for high-precision. gamma. -ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Houtermans, H.; Schaerf, K.; Reichel, F. (International Atomic Energy Agency, Vienna (Austria)); Debertin, K. (Physikalisch-Technische Bundesanstalt, Braunschweig (Germany, F.R.))

    1983-02-01

    The International Atomic Energy Agency organized an international comparison of methods applied in high-precision ..gamma..-ray spectrometry for the correction of dead-time and pile-up losses. Results of this comparison are reported and discussed.

  8. Calibration of the High Resolution Gamma Spectrometry Detection Systems from the Environmental Radioactivity Unit and Radiological Surveillance (ARU and RV); Calibracion de los Sistemas Detectores de Espectrometria Gamma de Alta Resolucion de la Unidad de Radiactividad Ambiental y Vigilancia Radiologica (URA y VR)

    Energy Technology Data Exchange (ETDEWEB)

    Suarez-Navarro, J. A.; Gasco, C.; Arana, M.; Suanez, A.

    2012-11-01

    In accordance with international regulations and with the quality criteria imposed by the internal quality system of the laboratory of gamma spectrometry, which belongs to the Unit of Environmental Radioactivity and Radiation Monitoring (URA y VR), it is necessary to perform a periodic calibration of the measurement systems of gamma spectrometry. The equipment calibration carries with the need for the preparation of the geometries of measurement and calibration in energy and in efficiencies. This report reflects the procedures for the preparation of the wide range of geometries available in the laboratory, as well as the different calibrations performed with those geometries in almost all the laboratory gamma detectors using the CANBERRA software Genie 2k. (Author) 9 refs.

  9. Results from the RESUME-95 exercise. In-situ gamma spectrometry performed at Vesivehmaa Airport, Finland

    Energy Technology Data Exchange (ETDEWEB)

    Raeaef, C.L. [Univ. Hospital MAS, Lund Univ., Dept. of Radiation Physics, Malmoe (Sweden)

    1997-12-31

    The Department of Radiation Physics in Malmoe has an agreement with the Swedish Radiation Protection Institute, in which we are obliged to perform instantaneous field measurements of gamma-emitting radionuclides in case of a major release of radionuclides in the environment. The department possesses a High Purity Germanium detector system (35 % commercial at 1.33 MeV) with a PC software spectrum analyser that was purchased and calibrated for this reason. The aim of our participation in the RESUME-95{sup 1} exercise, which took place in Vaeaexsy, Finland, in August 1995, was both to obtain efficiency values for different source geometries (both artificial and natural radionuclides) in field and to compare our results with those of other groups. Furthermore, this exercise was an ideal opportunity to test the full equipment under field conditions. (au).

  10. Results from the RESUME-95 exercise. In-situ gamma spectrometry performed at Vesivehmaa Airport, Finland

    Energy Technology Data Exchange (ETDEWEB)

    Raeaef, C L [Univ. Hospital MAS, Lund Univ., Dept. of Radiation Physics, Malmoe (Sweden)

    1998-12-31

    The Department of Radiation Physics in Malmoe has an agreement with the Swedish Radiation Protection Institute, in which we are obliged to perform instantaneous field measurements of gamma-emitting radionuclides in case of a major release of radionuclides in the environment. The department possesses a High Purity Germanium detector system (35 % commercial at 1.33 MeV) with a PC software spectrum analyser that was purchased and calibrated for this reason. The aim of our participation in the RESUME-95{sup 1} exercise, which took place in Vaeaexsy, Finland, in August 1995, was both to obtain efficiency values for different source geometries (both artificial and natural radionuclides) in field and to compare our results with those of other groups. Furthermore, this exercise was an ideal opportunity to test the full equipment under field conditions. (au).

  11. Gamma spectrometry of 285-04 ILAS gamma scan wires

    International Nuclear Information System (INIS)

    Dassel, G.; Buurveld, H.A.; Plakman, J.C.

    1996-12-01

    In the frame work of their on-going sustain programme for the material development and characterization of fusion reactors, ECN is investigating the irradiation behaviour of ferritic/martensitic steels. In the fourth irradiation experiment 285-04, 55 steel tensile samples have been irradiated up to 2.5 dpa. Four gamma scan wires from this experiment have been examined by gamma scanning. The results of the measurements have been described in this report. (orig.)

  12. Validation of Cs-137 measurement in food samples using gamma spectrometry system

    International Nuclear Information System (INIS)

    Yii Mei Wo; Kamarozaman Ishak

    2005-01-01

    Cs-137 was found to be one of major radionuclide contaminant present in foods consumed by human. In some countries, regulations required consumption foods moving in international trade to be scanned for caesium (Cs-134 and Cs-137) to ensure it does not exceeding the maximum permissible level. This is to ensure that the intake of such foods will not accumulate radionuclide until the significant level inside the human body. Gamma Spectrometry System was used to perform the measurement of caesium isotopes, because it was one of the easiest methods to be performed. This measuring method must be validated for several parameters include specificity, precision (repeatability), bias (accuracy), linearity, range, detection limit, robustness and ruggedness in order to ensure it is fit for the purpose. This paper would summarise how these parameters were fulfilled for this analytical method using several types certified reference materials. The same validated method would be considered workable on Cs-134 as well. (Author)

  13. Automatic Sample Changing System for Gamma-Ray Spectrometry; Changeur Automatique d'Echantillons Pourla Spectrometrie Gamma; Avtomaticheskaya sistema dlya smeny obraztsov pri gamma-spektrometrii; Cambiador Automatico de Muestras para Espectroscopia Gamma

    Energy Technology Data Exchange (ETDEWEB)

    Lamson, K. C.; Sesko, W. J.; Nicholson, G. C. [Northeastern Radiological Health Laboratory, Winchester, MA (United States)

    1965-10-15

    The detection of gamma-emitting radionuclides at environmental levels in biological media requires that the sensitivity of the counting system be high. To accumulate sufficiently precise data, it is often necessary to count samples for long periods of time - from one to several hours. The most efficient utilization of expensive low-background gamma-ray spectrometric counting equipment requires that it be operated on a continuous basis. This necessitates either the continuous presence of personnel or a completely automated system, including the changing of samples and recording of data. The purpose of this paper is to describe the automated gamma-ray spectrometry counting system designed, built and in use at the Northeastern Radiological Health Laboratory, Winchester, Massachusetts. The sample changing unit was designed to operate in conjunction with a large steel shield, any commercial unit with a front opening door being readily adaptable for this purpose. The changer is equipped to handle a variety of samples including biological and medical types. The unit consists of a revolving tray with a capacity for sixteen samples, an indexing system for positioning the samples, a mechanical arm with an attached electromagnet for inserting and removing the samples from the shield, and a lever for opening and closing the shield door. The changer has been completely integrated with a multichannel analyser with the provision of safety features to interrupt the cycle in case of malfunction at any step. After a preset counting period, the data are punched onto paper tape and processed by an IBM. 1620 computer. The first model of the sample changer, for which a patent is pending, has been in operation at the Northeastern Radiological Health Laboratory for about one year. During that time, it has been used extensively and has proven completely satisfactory. The total cost of the unit, including labour, was less than $ 2000. (author) [French] GAMMAPour deceler les radionucleides

  14. Self-attenuation correction in the environmental sample gamma spectrometry; Correcao de auto-absorcao na espectrometria gama de amostras ambientais

    Energy Technology Data Exchange (ETDEWEB)

    Venturini, Luzia; Nisti, Marcelo B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    1997-10-01

    Self-attenuation corrections were calculated for gamma ray spectrometry of environmental samples with densities from 0.42 g/ml up to 1.59 g/ml, measured in Marinelli beakers and polyethylene flasks. These corrections are to be used when the counting efficiency is calculated for water measured in the same geometry. The model of Debertin for Marinelli beaker, numerical integration and experimental linear attenuation coefficients were used. (author). 3 refs., 4 figs., 6 tabs.

  15. Validation of 226Ra, 228Ra and 210Pb measurements in soil and sediment samples through high resolution gamma ray spectrometry

    International Nuclear Information System (INIS)

    Dias, Danila Carrijo da Silva; Silva, Nivaldo Carlos da; Bonifacio, Rodrigo Leandro; Guerrero, Eder Tadeu Zenun

    2013-01-01

    Radionuclides found in ore extraction waste materials are a great source of concern regarding public health and environmental safety. One technique to determine the concentration of substances is high resolution gamma ray spectrometry using HPGe. Validating a measurement technique is essential to warrant high levels of quality to any scientific work. The Laboratory of Pocos de Caldas of the Brazilian Commission for Nuclear Energy partakes into a Quality Management System project, seeking Accreditation under ISO/IEC 17025 through the validation of techniques of chemical and radiometric analysis of environmental samples from water, soil and sediment. The focus of the Radon Laboratory at LAPOC is validation of Ra-226, Ra-228 and Pb-210 concentration determinations in soil and sediment through a gamma spectrometer system. The stages of this validation process included sample reception and preparation, detector calibration and sample analyses. Dried samples were sealed in metallic containers and analyzed after radioactive equilibrium between Ra-226 and daughters Pb-214 and Bi-214. Gamma spectrometry was performed using CANBERRA HPGe detector and gamma spectrum software Genie 2000. The photo peaks used for Ra-226 determination were 609 keV and 1020 keV of Bi-214 and 351 keV of Pb-214. For the Ra-228 determination a photopeak of 911 keV was used from its short half-life daughter Ac-228 (T1/2 = 6.12 h). For Pb-210, the photopeak of 46.5 keV was used, which, due to the low energy, self-absorption correction was needed. Parameters such as precision, bias/accuracy, linearity, detection limit and uncertainty were evaluated for that purpose. The results have pointed to satisfying results. (author)

  16. Gamma spectrometry of 285-03 ILAS gamma scan wires

    International Nuclear Information System (INIS)

    Dassel, G.; Buurveld, H.A.; Plakman, J.C.

    1996-12-01

    In the frame work of their on-going sustain programme for the material development and characterization of fusion reactors, ECN is investigating the irradiation behaviour of ferritic/martensitic steels. In the third irradiation experiment 285-03, 55 vanadium (V-4Cr-4Ti) tensile samples have been irradiated up to 6 dpa. Four gamma scan wires from this experiment have been examined by gamma scanning. The results of the measurements have been described in this report. (orig.)

  17. Two low-level gamma spectrometry systems of the IAEA Safeguards Analytical Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Parus, J L [IAEA, SAL, Vienna (Austria); Raab, W [IAEA, SAL, Vienna (Austria); Donohue, D [IAEA, SAL, Vienna (Austria); Jansta, V [IAEA, SAL, Vienna (Austria); Kierzek, J [IAEA, SAL, Vienna (Austria)

    1997-03-01

    A gamma spectrometry system designed for the measurement of samples with low and medium radioactivity (activity from a few to about 10{sup 4} Bq in the energy range from 25 to 2700 keV) has been installed at the IAEA Safeguards Analytical Laboratory in Seibersdorf. The system consists of 3 low level detectors: (1) n-type coaxial Ge with 42.4% relative efficiency, 1.85 keV FWHM at 1.33 MeV (2) planar Ge with 2000 mm{sup 2} area and 20 mm thickness, 562 eV FWHM at 122 keV (3) NaI(Tl) annulus of 25.4 cm diameter and 25.4 cm height, hole diameter 90 mm. (orig./DG)

  18. Comparison of results at area 1 and area 2 between different Swedish in-situ teams in the RESUME-95 exercise

    Energy Technology Data Exchange (ETDEWEB)

    Raeaef, C.L. [Malmoe Univ. Hospital, Lund Univ., Dept. of Radiation Physics (Sweden)

    1997-12-31

    In the beginning of 1996 the Department of Radiation Physics in Malmoe was commissioned by the Swedish Radiation Protection Institute to perform a compilation of the results obtained by the Swedish in-situ teams that participated in the RESUME-95 exercise. The aim of this survey is to study the coherence in the reported activity data between the groups. It is not the purpose to see this comparison as a performance ranking of individual laboratories. Any such comparison must be made with precaution since the teams generally have collected their data with different equipment and by different methods. In this work, all in-situ teams have been given code-names, where each team has been labelled a number from 1 to 5. For more details, the interested reader is referred to the internal reports made by each team that (supposedly) also are to be included in the major compilation of the in-situ gamma spectrometry in the RESUME-95 exercise by Danish Emergency Management Agency. (au).

  19. Comparison of results at area 1 and area 2 between different Swedish in-situ teams in the RESUME-95 exercise

    International Nuclear Information System (INIS)

    Raeaef, C.L.

    1997-01-01

    In the beginning of 1996 the Department of Radiation Physics in Malmoe was commissioned by the Swedish Radiation Protection Institute to perform a compilation of the results obtained by the Swedish in-situ teams that participated in the RESUME-95 exercise. The aim of this survey is to study the coherence in the reported activity data between the groups. It is not the purpose to see this comparison as a performance ranking of individual laboratories. Any such comparison must be made with precaution since the teams generally have collected their data with different equipment and by different methods. In this work, all in-situ teams have been given code-names, where each team has been labelled a number from 1 to 5. For more details, the interested reader is referred to the internal reports made by each team that (supposedly) also are to be included in the major compilation of the in-situ gamma spectrometry in the RESUME-95 exercise by Danish Emergency Management Agency. (au)

  20. Comparison of results at area 1 and area 2 between different Swedish in-situ teams in the RESUME-95 exercise

    Energy Technology Data Exchange (ETDEWEB)

    Raeaef, C L [Malmoe Univ. Hospital, Lund Univ., Dept. of Radiation Physics (Sweden)

    1998-12-31

    In the beginning of 1996 the Department of Radiation Physics in Malmoe was commissioned by the Swedish Radiation Protection Institute to perform a compilation of the results obtained by the Swedish in-situ teams that participated in the RESUME-95 exercise. The aim of this survey is to study the coherence in the reported activity data between the groups. It is not the purpose to see this comparison as a performance ranking of individual laboratories. Any such comparison must be made with precaution since the teams generally have collected their data with different equipment and by different methods. In this work, all in-situ teams have been given code-names, where each team has been labelled a number from 1 to 5. For more details, the interested reader is referred to the internal reports made by each team that (supposedly) also are to be included in the major compilation of the in-situ gamma spectrometry in the RESUME-95 exercise by Danish Emergency Management Agency. (au).

  1. Processing of gamma-ray spectrometric logs

    International Nuclear Information System (INIS)

    Umiastowski, K.; Dumesnil, P.

    1984-10-01

    CEA (Commissariat a l'Energie Atomique) has developped a gamma-ray spectrometric tool, containing an analog-to-digital converter. This new tool permits to perform very precise uranium logs (natural gamma-ray spectrometry), neutron activation logs and litho-density logs (gamma-gamma spectrometric logs). Specific processing methods were developped to treate the particular problems of down-hole gamma-ray spectrometry. Extraction of the characteristic gamma-ray peak, even if they are superposed on the background radiation of very high intensity, is possible. This processing methode enables also to obtain geological informations contained in the continuous background of the spectrum. Computer programs are written in high level language for SIRIUS (VICTOR) and APOLLO computers. Exemples of uranium and neutron activation logs treatment are presented [fr

  2. Gamma-ray spectrometry data collection and reduction by simple computing systems

    International Nuclear Information System (INIS)

    Op de Beeck, J.

    1975-01-01

    The review summarizes the present state of the involvement of relatively small computing devices in the collection and processing of gamma-ray spectrum data. An economic and utilitarian point of view has been chosen with regard to data collection in order to arrive at practically valuable conclusions in terms of feasibility of possible configurations with respect to their eventual application. A unified point of view has been adopted with regard to data processing by developing an information theoretical approach on a more or less intuitive level in an attempt to remove the largest part of the virtual disparity between the several processing methods described in the literature. A synoptical introduction to the most important mathematical methods has been incorporated, together with a detailed theoretical description of the concept gamma-ray spectrum. In accordance with modern requirements, the discussions are mainly oriented towards high-resolution semiconductor detector-type spectra. The critical evaluation of the processing methods reviewed is done with respect to a set of predefined criteria. Smoothing, peak detection, peak intensity determination, overlapping peak resolving and detection and upper limits are discussed in great detail. A preferred spectrum analysis method combining powerful data reduction properties with extreme simplicity and speed of operation is suggested. The general discussion is heavily oriented towards activation analysis application, but other disciplines making use of gamma-ray spectrometry will find the material presented equally useful. Final conclusions are given pointing to future developments and shifting their centre of gravity towards improving the quality of the measurements rather than expanding the use of tedious and sophisticated mathematical techniques requiring the limits of available computational power. (author)

  3. Measurement of radon concentration in water by means of {alpha}, {gamma} spectrometry. Radon concentration in ground and spring water in Hiroshima Prefecture

    Energy Technology Data Exchange (ETDEWEB)

    Shizuma, Kiyoshi [Hiroshima Univ. (Japan)

    1997-02-01

    Radon ({sup 222}Rn, T{sub 1/2}=3.8235{+-}0.0003d) is {alpha}-ray releasing nuclide, so that it can not be detected by {gamma}-ray measurement. But, the daughter nuclides {sup 214}Pb (T{sub 1/2}=26.8 min) and {sup 214}Bi (T{sub 1/2}=19.9 min) release {gamma}-ray, accordingly they are measured by Ge detector. Their radioactive equilibrium is kept in the closed vessel, because their half-lives are shorter than that of radon. We developed a measurement method of radon concentration by means of {gamma}-spectrometry. We applied this method to catch radon in the atmosphere by active carbon. The same principle can be applied to radon in water. Radon concentrations in the ground water were measured in 22 points in the Higashi-Hiroshima city and 82 points in the Hiroshima prefecture. The efficiencies of {gamma}-ray were determined. The radon concentration showed between 11 and 459 Bq/l and the average was 123 Bq/l. The high concentration of radon was distributed in the spring of granitic layer and higher concentration of radon were observed in the ground water of fault. (S.Y.)

  4. Direct dating of Tantavel man by non-destructive gamma-ray spectrometry of fossil human skull Arago XXI

    International Nuclear Information System (INIS)

    Yokoyama, Yuji; Nguyen, Huu-Van

    1981-01-01

    A new method to date prehistoric samples is proposed. Non-destructive gamma-ray spectrometry with semi-conductor detector was used in the direct determination of the activities of 238 U, 234 U, 231 Pa, 230 Th and 228 Th. An age of (400sub(-96)sup(+infinite))x10 3 years was obtained from the 230 Th/ 238 U ratio of 0.975+-0.030 [fr

  5. Correcting the effects of the matrix using capture gamma-ray spectrometry: Application to measurement by Active Neutron Interrogation; Correction des effets de matrice par spectrometrie des rayonnements gamma de capture: Application a la mesure par Interrogation Neutronique Active (I.N.A.)

    Energy Technology Data Exchange (ETDEWEB)

    Baudry, G.

    2003-11-15

    In the field of the measurement of low masses of fissile material ({sup 235}U, {sup 239}Pu, {sup 241}Pu) in radioactive waste drums, the Active Neutron Interrogation is a non-destructive method achieving good results. It does however remain reliant upon uncertainties related to the matrix effects on interrogation and fission neutrons. The aim of this thesis is to develop a correction method able to take into account these matrix effects by quantifying the amount of absorbent materials (chlorine and hydrogen) in a 118- liter homogeneous matrix. The main idea is to use the gamma-ray spectrometry of gamma emitted by neutron captures to identify and quantify the composition of the matrix. An indicator from its chlorine content is then deduced in order to choose the calibration coefficient which best represents the real composition of the matrix. This document firstly presents the needs of control and characterization of radioactive objects, and the means used in the field of nuclear measurement. Emphases is put in particular on the Active Neutron Interrogation method. The matrices of interest are those made of light technological waste (density {<=} 0,4 g/cm{sup 3}) containing hydrogenated and chlorinated materials. The advantages of gamma-rays emitted by neutron captures for the determination of a chlorine content indicator of the matrices and the principles of the correction method are then explained. Measurements have been firstly realized with an existing Neutron Interrogation device (PROMETHEE 6). Such measurements have proven its inadequacy: no signal from the matrix hydrogen was detected, due to an intense signal from the polyethylene contained in some cell elements. Moreover, the matrix chlorine content appeared difficult to be measured. A new and specific device, named REGAIN and dedicated to active gamma-rays spectrometry, was defined with the Monte-Carlo N-Particle (MCNP) code. The experiments conducted with this new device made it possible to detect the

  6. Experience gained in gamma spectroscopy; Experience acquise dans la spectrometrie gamma

    Energy Technology Data Exchange (ETDEWEB)

    Jeanmaire, L [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    There are two types of method which make it possible to estimate the internal contamination of individuals. On the one hand these are the indirect techniques based on measurements of the excreted products, on the other there are the direct techniques in which attempts are made to measure directly the radio-activity existing in the organism. We propose to give a few of the results obtained by the direct method using equipment built by the Commissariat a l'Energie Atomique. The apparatus consists of a {gamma} spectrometer. It includes: 1) A crystal of sodium iodide 20 cm in diameter and 10 cm high. The large size of this crystal ensures a good sensitivity and makes it possible to carry out rapid measurements. 2) A 25 channel type SAE 25 selector which classifies the pulses according to their amplitude. It is therefore possible to distinguish between {gamma} rays of varying energy. 3) A comparatively very light radiation protection, consisting of only 5 cm thickness of lead which diminishes the ambient {gamma} ray intensity to a sufficient level for the majority of the measurements. A certain collimation is thus obtained which makes it possible to localise the source approximately and to reduce the undesirable effects of external contamination. (author) [French] Deux types de methodes permettent d'apprecier la contamination interne d'un individu. D'une part, les techniques indirectes basees sur la mesure des produits excretes, d'autre part, les techniques directes au moyen desquelles on essaie de mesurer directement la radioactivite existant dans l'organisme. Nous nous proposons d'indiquer quelques resultats obtenus par la methode directe, au moyen d'ensembles realises par le Commissariat a l'Energie Atomique. L'appareillage est un spectrometre {gamma}. II comprend: 1) Un cristal d'iodure de sodium de 20 cm de diametre et 10 cm de hauteur. La grande taille de ce cristal assure une bonne sensibilite et permet d'effectuer des mesures rapides. 2) Un selecteur a 25 canaux

  7. Comparative and Absolute Measurements of 11 Inorganic Constituents of 38 Human Tooth Samples with Gamma-ray Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Samsahl, K [AB Atomenergi, Stockholm (Sweden); Soeremark, R [The Clinical Laboratory and the Dept. of Prosthetics of the Royal School of Dentistry, Stockholm (Sweden)

    1961-12-15

    The mean concentrations of the following elements have been simultaneously determined in normal human dentine, enamel and dental calculus with gamma-ray spectrometry; Na, P, Cl, Ca, Mn, Cu, Zn, Br, Sr, W and Au. In a typical run one sample each of dentine, enamel and dental calculus were irradiated together with standards of the elements to be determined in a thermal neutron flux of 2 x 10{sup 12} n/cm/sec for 20 hours. The chemical elements were separated into nine groups with ion exchange technique before the subsequent gamma spectrometric measurements. One man can manage the chemical separations and take the necessary gamma spectra from a run in one day. In a few samples of dentine, enamel and dental calculus which had been irradiated in a thermal neutron flux of 7 x 10{sup 13} n/cm/sec for one week the additional long lived trace elements were qualitatively determined Cr, Fe, Co, Rb, Ag, Sb, Cs and Ba.

  8. Comparative and Absolute Measurements of 11 Inorganic Constituents of 38 Human Tooth Samples with Gamma-ray Spectrometry

    International Nuclear Information System (INIS)

    Samsahl, K.; Soeremark, R.

    1961-12-01

    The mean concentrations of the following elements have been simultaneously determined in normal human dentine, enamel and dental calculus with gamma-ray spectrometry; Na, P, Cl, Ca, Mn, Cu, Zn, Br, Sr, W and Au. In a typical run one sample each of dentine, enamel and dental calculus were irradiated together with standards of the elements to be determined in a thermal neutron flux of 2 x 10 12 n/cm/sec for 20 hours. The chemical elements were separated into nine groups with ion exchange technique before the subsequent gamma spectrometric measurements. One man can manage the chemical separations and take the necessary gamma spectra from a run in one day. In a few samples of dentine, enamel and dental calculus which had been irradiated in a thermal neutron flux of 7 x 10 13 n/cm/sec for one week the additional long lived trace elements were qualitatively determined Cr, Fe, Co, Rb, Ag, Sb, Cs and Ba

  9. Neutron activation analysis of lipsticks using gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Mirsa, G.; Mittal, V.K.

    2004-01-01

    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)

  10. A low-energy set-up for gamma-ray spectrometry of NORM tailored to the needs of a secondary smelting facility.

    Science.gov (United States)

    Lutter, G; Schreurs, I Vandael; Croymans, T; Schroeyers, W; Schreurs, S; Hult, M; Marissens, G; Stroh, H; Tzika, F

    2017-08-01

    A measurement station dedicated for quantitative radiological characterisation of naturally occurring radionuclides in a metallurgical company and based on gamma-ray spectrometry was developed. The station is intended for performing quality control of final non-ferrous metal products and for radiological checks of incoming materials. A low-background point-contact HPGe-detector was used and the signal was split in two branches to enable collecting simultaneously spectra with high amplification (for gamma-ray energies below 250keV) and low amplification. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Gamma spectrometry and plastic-scintillator inherent background

    International Nuclear Information System (INIS)

    Pomerantsev, V.V.; Gagauz, I.B.; Mitsai, L.I.; Pilipenko, V.S.; Solomonov, V.M.; Chernikov, V.V.; Tsirlin, Y.A.

    1988-01-01

    The authors measured the energy resolution for a linear dependence of light yield on gamma radiation energy of gamma spectrometers based on plastic scintillation detectors for several plastic scintillators. If there were several gamma lines from the source the line with the highest energy was used to eliminate distortion due to overlap from the Compton background from gamma radiation of higher energy. Attenuation lengths were calculated. The tests were based on three modes of interaction between the gamma radiation and the scintillator: Compton scattering, the photoelectric effect, and pair formation. The contribution from light collection was also considered. The scintillators tested included polystyrene, polymethyl methacrylate, cesium iodide, and sodium iodide. Gamma sources included cesium 137, sodium 22, potassium 40, yttrium 88, thorium 232, and plutonium-beryllium

  12. Simultaneous Determination of Food-Related Biogenic Amines and Precursor Amino Acids Using in Situ Derivatization Ultrasound-Assisted Dispersive Liquid-Liquid Microextraction by Ultra-High-Performance Liquid Chromatography Tandem Mass Spectrometry.

    Science.gov (United States)

    He, Yongrui; Zhao, Xian-En; Wang, Renjun; Wei, Na; Sun, Jing; Dang, Jun; Chen, Guang; Liu, Zhiqiang; Zhu, Shuyun; You, Jinmao

    2016-11-02

    A simple, rapid, sensitive, selective, and environmentally friendly method, based on in situ derivatization ultrasound-assisted dispersive liquid-liquid microextraction (in situ DUADLLME) coupled with ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) using multiple reaction monitoring (MRM) mode has been developed for the simultaneous determination of food-related biogenic amines and amino acids. A new mass-spectrometry-sensitive derivatization reagent 4'-carbonyl chloride rosamine (CCR) was designed, synthesized, and first reported. Parameters and conditions of in situ DUADLLME and UHPLC-MS/MS were optimized in detail. Under the optimized conditions, the in situ DUADLLME was completed speedily (within 1 min) with high derivatization efficiencies (≥98.5%). With the cleanup and concentration of microextraction step, good analytical performance was obtained for the analytes. The results showed that this method was accurate and practical for quantification of biogenic amines and amino acids in common food samples (red wine, beer, wine, cheese, sausage, and fish).

  13. Field {gamma}-ray spectrometry on the Vulcano island (Aeolian Arc, Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Chiozzi, P.; Pasquale, V.; Russo, D.; Verdoya, M. [Dipartimento di Scienze della Terra, Universita di Genova, Genoa (Italy); De Felice, P. [Istituto Nazionale di Metrologica delle Radiazioni Ionizzanti ENEA, Dipartimento Ambiente, Centro Ricerche Casaccia, Rome (Italy)

    1999-08-01

    In situ NaI(Tl) {gamma}-ray spectrometric measurements on the Vulcano island show that the magmatic evolution of the main structural units is reflected by the uranium, thorium and potassium concentrations. The results allowed us to delineate two temporal and radiometric districts. The older district comprises lava flows and pyroclastics of mafic composition forming the whole southern part of the island, with an equivalent uranium concentration and an eTh/eU ratio ranging, on average, from 2.9 to 3.4 ppm and from 2.4 to 4.1, respectively. Rocks of the younger district, ranging from leucitic tephritic and trachytic to rhyolitic composition, show higher K contents (about 6%) and more variable eTh/eU ratios (2.4-6.1)

  14. Correcting the effects of the matrix using capture gamma-ray spectrometry: Application to measurement by Active Neutron Interrogation

    International Nuclear Information System (INIS)

    Baudry, G.

    2003-11-01

    In the field of the measurement of low masses of fissile material ( 235 U, 239 Pu, 241 Pu) in radioactive waste drums, the Active Neutron Interrogation is a non-destructive method achieving good results. It does however remain reliant upon uncertainties related to the matrix effects on interrogation and fission neutrons. The aim of this thesis is to develop a correction method able to take into account these matrix effects by quantifying the amount of absorbent materials (chlorine and hydrogen) in a 118- liter homogeneous matrix. The main idea is to use the gamma-ray spectrometry of gamma emitted by neutron captures to identify and quantify the composition of the matrix. An indicator from its chlorine content is then deduced in order to choose the calibration coefficient which best represents the real composition of the matrix. This document firstly presents the needs of control and characterization of radioactive objects, and the means used in the field of nuclear measurement. Emphases is put in particular on the Active Neutron Interrogation method. The matrices of interest are those made of light technological waste (density ≤ 0,4 g/cm 3 ) containing hydrogenated and chlorinated materials. The advantages of gamma-rays emitted by neutron captures for the determination of a chlorine content indicator of the matrices and the principles of the correction method are then explained. Measurements have been firstly realized with an existing Neutron Interrogation device (PROMETHEE 6). Such measurements have proven its inadequacy: no signal from the matrix hydrogen was detected, due to an intense signal from the polyethylene contained in some cell elements. Moreover, the matrix chlorine content appeared difficult to be measured. A new and specific device, named REGAIN and dedicated to active gamma-rays spectrometry, was defined with the Monte-Carlo N-Particle (MCNP) code. The experiments conducted with this new device made it possible to detect the hydrogen from the

  15. MALDI Mass Spectrometry Imaging for Visualizing In Situ Metabolism of Endogenous Metabolites and Dietary Phytochemicals

    Science.gov (United States)

    Fujimura, Yoshinori; Miura, Daisuke

    2014-01-01

    Understanding the spatial distribution of bioactive small molecules is indispensable for elucidating their biological or pharmaceutical roles. Mass spectrometry imaging (MSI) enables determination of the distribution of ionizable molecules present in tissue sections of whole-body or single heterogeneous organ samples by direct ionization and detection. This emerging technique is now widely used for in situ label-free molecular imaging of endogenous or exogenous small molecules. MSI allows the simultaneous visualization of many types of molecules including a parent molecule and its metabolites. Thus, MSI has received much attention as a potential tool for pathological analysis, understanding pharmaceutical mechanisms, and biomarker discovery. On the other hand, several issues regarding the technical limitations of MSI are as of yet still unresolved. In this review, we describe the capabilities of the latest matrix-assisted laser desorption/ionization (MALDI)-MSI technology for visualizing in situ metabolism of endogenous metabolites or dietary phytochemicals (food factors), and also discuss the technical problems and new challenges, including MALDI matrix selection and metabolite identification, that need to be addressed for effective and widespread application of MSI in the diverse fields of biological, biomedical, and nutraceutical (food functionality) research. PMID:24957029

  16. Coincidence summing corrections for positron emitters in germanium gamma spectrometry

    International Nuclear Information System (INIS)

    Richardson, A.E.; Sallee, W.W.; New Mexico State Univ., Las Cruces

    1990-01-01

    For positron emitters, 511 keV annihilation quanta are in coincidence with other gamma rays in the decay scheme. If the positrons are not localized at the point of decay, annihilation quanta will be produced at a site some distance from the point of emission. The magnitude of the summing coincidence effect will depend upon the position of annihilation. A method for determining the magnitude of the summing effect for a single gamma of energy E in coincidence with the annihilation gammas from non-localized positrons has been developed which makes use of the counting data for the full energy peaks for both the gamma ray (E) and the 511 keV annihilation gammas. With this data and efficiency calibration data one can determine the average total efficiency for the annihilation positions from which 511 keV gammas originate, and thereby obtain the summing correction factor, SCF, for gamma ray (E). Application of the method to a 22 Na NIST standard gave excellent agreement of observed emission rates for the 1275 keV gamma with the NIST value for wide ranging degrees of positron localization having summing correction factors ranging from 1.021 to 1.505. The method was also applied successfully to 58 Co in neutron-irradiated nickel foils. The method shows promise as a check on the accuracy of the efficiency calibration for a particular detector geometry at the 511 keV energy and energies for other gammas associated with positron emission. (orig.)

  17. Characterization of radioactive orphan sources by gamma spectrometry; Caracterizacion de fuentes huerfanas radiactivas por espectrometria gamma

    Energy Technology Data Exchange (ETDEWEB)

    Cruz W, H., E-mail: wcruz@ipen.gob.pe [Instituto Peruano de Energia Nuclear (PGRR/IPEN), Lima (Peru). Planta de Gestion de Residuos Radiactivos

    2013-07-01

    The sealed radioactive sources are widely applicable in industry. They must have a permanent control and must be registered with the Technical Office of the National Authority (OTAN). However, at times it has identified the presence of abandoned sealed sources unknown to the owner. These sources are called 'orphan sources'. Of course these sources represent a high potential risk because accidents can trigger dire consequences depending on your activity and chemical form in which it presents the radioisotope. This paper describes the process and the actions taken to characterize two orphan radioactive sources from the smelter a Aceros Arequipa. For characterization we used a gamma spectrometry system using a detector NaI(Tl) 3″ x 3″ with a multichannel analyzer Nucleus PCA-II. The radioisotope identified was cesium - 137 ({sup 137}Cs) in both cases. Fortunately, the sources maintained their integrity would otherwise have generated significant pollution considering the chemical form of the radioisotope and easy dispersion. (author)

  18. Equipment and applications for gamma spectrometry

    International Nuclear Information System (INIS)

    Hemingway, J.D.

    1986-01-01

    In this article the theoretical aspects of gamma spectroscopy are discussed. Coaxial germanium detectors and planar detectors are described. Applications of gamma spectroscopy to the detection of the exposure of a population to naturally occuring radioactive gases and their daughter products; the accumulation of iodine isotopes in the thyroid and measuring the quantity of 239 Pu in the lungs are discussed. (UK)

  19. Application of gamma spectrometry technique in combination with weighing for material balance taking in the production of highly enriched U-A1 fuel

    International Nuclear Information System (INIS)

    Serin, P.A.

    1975-07-01

    The purpose of this project is to obtain the data on material balance for a batch of highly enriched U-Al alloys (used in the NRX and NRU reactors) during production of fuel, using gamma spectrometry (mainly the 186 KeV photopeak) and weighing, and to determine operational data of the Agency's single channel stabilized spectrometer (SAM-1) for measurement of the product typical for the production of highly enriched U-Al fuel (U-Al billets, fuel elements, scrap). The data collected indicates that gamma spectrometry using the single channel stabilized spectrometer is a valid non-destructive method of determining quantitatively U-235 content of U-Al alloy in the form of cast billets or extruded fuel elements providing that adequate standards are available. An accuracy of better than + 1% relative can be obtained using a simple jig to provide reproducible counting geometry. Count rates should be kept well below the saturation level of the detector and counter, preferably by a lead collimator in front of the detector. This non-destructive method is not easily applicable to scrap because of the inability to maintain constant geometry and to prepare standards closely similar in size and shape to the samples

  20. LAFARA: a new underground laboratory in the French Pyrénées for ultra low-level gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Beek, P. van; Souhaut, M.; Lansard, B.; Bourquin, M.; Reyss, J.-L.; Ballmoos, P. von; Jean, P.

    2013-01-01

    We describe a new underground laboratory, namely LAFARA (for “LAboratoire de mesure des FAibles RAdioactivités”), that was recently created in the French Pyrénées. This laboratory is primarily designed to analyze environmental samples that display low radioactivity levels using gamma-ray spectrometry. Two high-purity germanium detectors were placed under 85 m of rock (ca. 215 m water equivalent) in the tunnel of Ferrières (Ariège, France). The background is thus reduced by a factor of ∼20 in comparison to above-ground laboratories. Both detectors are fully equipped so that the samples can be analyzed in an automatic mode without requiring permanent presence of a technician in the laboratory. Auto-samplers (twenty positions) and systems to fill liquid nitrogen automatically provide one month of autonomy to the spectrometers. The LAFARA facility allows us to develop new applications in the field of environmental sciences based on the use of natural radionuclides present at low levels in the environment. As an illustration, we present two of these applications: i) dating of marine sediments using the decay of 226 Ra in sedimentary barite (BaSO 4 ), ii) determination of 227 Ac ( 231 Pa) activities in marine sediment cores. - Highlights: ► We describe a new underground laboratory that allows us to conduct low-background gamma-ray spectrometry. ► The background in the underground laboratory is reduced by a factor of ∼20 in comparison to above-ground laboratories. ► The 2 gamma spectrometers are equipped so that they can run automatically (one month of autonomy).

  1. Radon fixation for determination of 224Ra, 226Ra and 228Ra via gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Herranz, M.; Idoeta, R.; Abelairas, A.; Legarda, F.

    2006-01-01

    The aim of this work is the improvement of the procedure for the determination of radium isotopes activities in water, which is done through radiochemical separation and subsequent gamma-ray spectrometry. In addition, radon gas retention is studied using different activated carbon materials. The results of the IAEA Proficiency test: 'Determination of radium and uranium radionuclides in water' of December 2002 [IAEA, 2003. Analytical quality control services: determination of radium and uranium radionuclides in water. Preliminary Report, Seibersdorf] are considered for this work

  2. A Field Test of the New Portable Gamma Spectrometry System

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jung-Ki; Park, Uk Ryang; Park, Seunghoon; Chung, Heejun; Kwak, Sung-Woo [Korea Institute of Nuclear Non-proliferation and Control, Daejeon (Korea, Republic of); Kim, Yongkwn [NuCare Medical Systems, Inc., Incheon (Korea, Republic of)

    2015-10-15

    In order to perform a field test of the system, the measurement of U-235 enrichment for nuclear fuel pellets was conducted along with the IAEA Physical Inventory Verification (PIV) inspection at the KEPCO Nuclear Fuel (KNF). The enrichment value of U-235 was calculated based on the total counts of the 185.7 keV photopeak and compared with the reference line, drawn by certified sources. The goal of this study is to experimentally evaluate the system performance of the developed system. In this study, the new portable gamma spectrometry system showed a good linearity (R{sup 2}=1) but overestimated the enrichment values than IAEA inspection device. It could be caused by the stability of the new system since it found, right after this measurement, that the accuracy of the system gradually increases and becomes stable over time. Further steps will optimize the design parameter based on these results and repeat measurement with the same samples under the same environment.

  3. In-situ Measurements and Analysis of Naturally Occurring Radioactive Materials

    International Nuclear Information System (INIS)

    Mueller, W.F.; Ilie, G.; Russ, W.R.; Lange, H.J.; Rotty, M.

    2013-06-01

    The measurement and quantification of naturally occurring radioactive materials (NORM) is an important element of workplace radioprotection in key industries such as oil and gas production, heavy metals mining and refining, coal burning waste, and water treatment. Monitoring of NORM content in home building materials is another challenge for human safety in the prevention of chronic dose uptake. Materials are classified NORM in case they contain significant amounts of the decay chains of U-238 (Ra-226 as a long lived daughter), U-235 or Th- 232 or the primordial nuclide K-40. Due to the decay of the radionuclides, gamma rays with a signature in the energy range from 45 keV up to 2615 keV are emitted. The most accurate method to measure NORM in a sample is to use a high resolution spectrometric instrument such as a germanium detector in a well-shielded laboratory environment. The shield is used to prevent background with the same signature from the building material of the laboratory. There are occasions in which one is required to assay samples in the field. These in situ field applications may require performing measurements with reduced (or no) background shielding conditions, or involve the use of medium resolution spectrometric instruments such as LaBr 3 or NaI detectors. In-situ analyses such as these have increased complexity. The reduced shielding enforces the subtraction of NORM events produced from the environment but the sample material and container can also shield the detector against this background thus biasing the measured results if not appropriately accounted. The use of medium resolution detectors has additional complications that the multiplicity of gamma-rays from NORM materials is such that most of the gamma-rays are interfering and thus require a very careful quantitative analysis. In this presentation, we will discuss the details of the NORM source term both in the environment and what could potentially be in the sample. We will also discuss

  4. A New Method for Processing Airborne Gamma Ray Spectrometry Data for Mapping Low Level Contaminations

    DEFF Research Database (Denmark)

    Aage, Helle Karina; Korsbech, Uffe C C; Bargholz, Kim

    1999-01-01

    A new technique for processing airborne gamma ray spectrometry data has been developed. It is based on the noise adjusted singular value decomposition method introduced by Hovgaard in 1997. The new technique opens for mapping of very low contamination levels. It is tested with data from Latvia...... where the remaining contamination from the 1986 Chernobyl accident together with fallout from the atmospheric nuclear weapon tests includes Cs-137 at levels often well below 1 kBq/m(2) equivalent surface contamination. The limiting factors for obtaining reliable results are radon in the air, spectrum...

  5. Improvements on Low Level Activity Gamma Measurements and X-ray Spectrometry at the CEA-MADERE Measurement Platform

    OpenAIRE

    Sergeyeva Victoria; Domergue Christophe; Destouches Christophe; Girard Jean Michel; Philibert Hervé; Bonora Jonathan; Thiollay Nicolas; Lyoussi Abdallah

    2016-01-01

    The CEA MADERE platform (Measurement Applied to DosimEtry in REactors) is a part of the Instrumentation Sensors and Dosimetry Laboratory (LDCI). This facility is dedicated to the specific activity measurements of solid and radioactive samples using Gamma and X-ray spectrometry. MADERE is a high-performance facility devoted to neutron dosimetry for experimental programs performed in CEA and for the irradiation surveillance programmes of PWR vessels. The MADERE platform is engaged in a continuo...

  6. Extraction of gold and mercury from sea water with bismuth diethyldithiocarbamate prior to neutron activation-. gamma. -spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Yu, J.C.; Lo, J.M.; Wai, C.M. (Idaho Univ. Moscow (USA). Dept. of Chemistry)

    1983-11-01

    Gold and mercury in sea water can be selectively extracted by bismuth diethyldithiocarbamate into chloroform at pH <= 1. The matrix species and many other trace elements in the system are effectively removed during extraction. When neutron activation-..gamma..-spectrometry is used, the detection limits for gold and mercury are 0.001 and 0.01 ..mu..g l/sup -1/, respectively. The relative precision is 9% for gold and 13% for mercury.

  7. Emergency response exercise of laboratories equipped with gamma spectrometry

    International Nuclear Information System (INIS)

    Mala, H.; Jezkova, T.; Rulik, P.; Beckova, V. et al.

    2014-01-01

    Seven laboratories equipped with semiconductor gamma spectrometry (HPGe detectors) are currently included in the Radiation Monitoring Network (RMN) in the Czech Republic. These laboratories have more than 30 spectrometric chains and approximately 20 'experts' and 70 'users' who would guarantee measurements during the radiological emergency (RE). The emergency exercise was carried out in 5 of them in 2014 (in 4 of them also in 2013). The aim was to test repeatedly their capacity in existing technical facilities and with current staff in the event of a RE and identify problems (bottlenecks) in the whole process from receipt of samples to entering the results into the central database of RMN. Duration of the exercise was 12 hours, due to the shortage of staff; work in one 12-hour shift is presumed during a RE, which the laboratories should be able to provide for 14 days. These exercise samples covered a wide range of commodities that would probably come to the laboratories during the RE (aerosol filters, sorbents for sorption of gaseous forms of iodine, fallout, surface and drinking waters, food chain components and soils). Some of the samples were previously spiked with 85 Sr, 88 Y and 40 K (in the exercise these nuclides represented actual contamination that would occur in RE); liquid samples were spiked with 85 Sr and 88 Y and bulk materials with 40 K.During the exercise almost 800 samples were analysed; in addition, the automatic gamma counter (GA) in Prague laboratory measured other 90 samples automatically during the night (samples were prepared during the day-shift). On the basis of the results the total measuring capacity of the laboratories of RMN CR was estimated at about 1300 samples per day. (authors)

  8. Analysis of spectra from portable handheld gamma-ray spectrometry for terrain comparative assessment

    International Nuclear Information System (INIS)

    Dias, Flávio; Lima, Marco; Sanjurjo-Sánchez, Jorge; Alves, Carlos

    2016-01-01

    Geological characteristics can have impacts on societal development by, e.g., geotechnical issues and radiological hazard levels. Due to urban sprawl, there is an increasing need for detailed geological assessment. In this work are analysed data from portable handheld gamma-ray spectra (K, eU and eTh) obtained in granitic and Silurian metaclastic outcrops as well as in an profile, roughly N–S, on soil covered terrains transecting a mapped contact between these rock types (the profile's northern extremity is at locations mapped as granite). Estimations from gamma-ray spectra were studied by univariate and multivariate analyses. K, eU and eTh values were higher on granite in relation to Silurian metaclastic rocks. The northern extremity of the profile showed clearly higher contents of eTh and this contrast was supported by univariate statistical tools (normality plot and Wilk–Shapiro test; boxplots). A ternary plot with the contribution of the elements to gamma-ray absorbed dose showed the separation of granite from Silurian metaclastic rocks with the former being nearer the eTh vertex. The points in the northern extremity of the profile are nearer the eTh vertex than the other points on the profile. These visual suggestions were supported by hierarchical cluster analysis, which was able to differentiate between granite and metaclastic outcrops and separate portions of the profile located on different terrains. Portable gamma-ray spectrometry showed, hence, the potential to distinguish granite and metaclastic terrains at a scale useful for engineering works. These results can also be useful for a first comparative zoning of radiological hazards (which are higher for granite). - Highlights: • Contents of K, eU and eTh were estimated by portable gamma-ray spectra. • Spectra were acquired on a profile across a soil covered granite/metaclastic contact. • Spectra were also collected on granite and Silurian metaclastic outcrops. • Obtained estimations were

  9. Determination of activity by gamma spectrometry of radionuclides present in drums of residues generated in nuclear centrals; Determinacion de actividad por espectrometria gamma de radionucleidos presentes en tambores de residuos generados en centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, J.C.; Fernandez, J. [Autoridad Regulatoria Nuclear, Av. Del Libertador 8250, Ciudad Autonoma de Buenos Aires (Argentina)]. e-mail: jaguiar@cae.arn.gov.ar

    2006-07-01

    The generation of radioactive residuals in nuclear centrals as CNA I (Atucha I Nuclear Central) and CNE (Embalse Nuclear Central) makes that the measurement of those radionuclides has been a previous stage to the waste management. A method used in those nuclear centrals it is the gamma spectrometry with HPGe detectors, previous to the immobilization of the residual in a cemented matrix, with this the contact with the external agents and its possible dispersion to the atmosphere in the short term is avoided. The ARN (Nuclear Regulatory Authority) of Argentina it carries out periodically intercomparisons and evaluations of the measurement and procedures systems used in the nuclear power stations for the correct measurement and determination of activity of radioactive residuals by gamma spectrometry. In this work an independent method of measurement is exposed to the nuclear power stations. To determine the activity of the residuals by gamma spectrometry deposited in drums, it is required of the precise knowledge of the efficiency curve for such geometry and matrix. Due to the RNA doesn't have a pattern of these characteristics, a mathematical model has been used to obtain this efficiency curve. For it, it is necessary to determine previously: 1) the geometric efficiency or solid angle sustained by the source-detector system (drum-detector) applying a mathematical model described in this work. 2) To estimate the auto-attenuation factor that present the photons in the cemented matrix, these calculations are carried out with a simple equation and its are verified with the Micro Shield 6.10 program. The container commonly used by these nuclear power stations its are drums for 220 liters constructed with SAE 1010 steel and with a thickness of 0.127 cm, with an approximate weight 7.73 Kg., internal diameter of 57.1 cm, and height: 87 cm. The results obtained until the moment register a discrepancy from 5 to 10% with relationship to the measurements carried out by the

  10. Burn up determination of IEAR-1 fuel elements by non destructive gamma ray spectrometry method

    International Nuclear Information System (INIS)

    Soares, A.J.

    1977-01-01

    Measurement of nuclear fuel burn up by non destructive gamma ray spectrometry is discussed, and results of such measurements, made at the Instituto de Energia Atomica (IEA), are given. Specifically, the burn up of an MTR (Material Testing Reactor) fuel element removed from the IEAR-1 swimming pool reactor in 1958 is evaluated from the measured Cs-137 activity, which gives a single 661,6 keV gamma ray. Due to the long decay time of the test element, no other fission decay product activity could be detected. Analysis of measurements, made with a 3'' x 3'' NaI(Tl) detector at 330 distinct points of the element, showed the total burn up to 3.3 +- -+ 0.8 mg. This is in agreement with a calculated value. As the maximum temperature of IEAR-1 fuel elements is of the order of 40 0 C, migration effects of Cs-137 was not considered, this being significant only at fuel temperature in excess of 1000 0 C [pt

  11. Detection of methamphetamine in the presence of nicotine using in situ chemical derivatization and ion mobility spectrometry.

    Science.gov (United States)

    Ochoa, Mariela L; Harrington, Peter B

    2004-02-15

    The detection of methamphetamine in the presence of nicotine has been successfully accomplished using in situ chemical derivatization with propyl chloroformate as the derivatization reagent and ion mobility spectrometry (IMS). The rapid detection of methamphetamine is important for forensic scientists in order to establish a chain of evidence and link criminals to the crime scene. Nicotine is pervasive in clandestine drug laboratories from cigarette smoke residue. It has been demonstrated that nicotine obscures the methamphetamine peaks in ion mobility spectrometers due to their similar charge affinities and ion mobilities, which makes their detection a challenging task. As a consequence, false positive or negative responses may arise. In situ chemical derivatization poses as a sensitive, accurate, and reproducible alternative to remove the nicotine background when detecting nanogram amounts of methamphetamine. The derivatization agent was coated onto the sample disk, and the derivatization product corresponding to propyl methamphetamine carbamate was detected. In the present study, in situ chemical derivatization was demonstrated to be a feasible method to detect methamphetamine hydrochloride as the carbamate derivative, which was baseline-resolved from the nicotine peak. Alternating least squares (ALS) was used to model the datasets. A mixture containing both compounds revealed reduced mobilities of 1.61 cm(2)/V.s and 1.54 cm(2)/V.s for methamphetamine and nicotine, respectively. The reduced mobility of propyl methamphetamine carbamate was found at 1.35 cm(2)/V.s.

  12. In situ gamma ray measurements of radionuclides at a disused phosphate mine on the West Coast of South Africa

    International Nuclear Information System (INIS)

    Bezuidenhout, Jacques

    2015-01-01

    High levels of uranium and its radioactive progeny like radium is normally associated with phosphate mining. In Situ gamma ray spectroscopy as a survey tool has been successfully applied to assess radionuclide concentrations in various geographical environments. A transportable and robust gamma ray detection system (GISPI) was therefore employed to determine the concentrations of naturally occurring radionuclides at a disused phosphate mine on the West Coast of South Africa. The concentrations of radium, thorium and potassium were measured and plotted. The measurements showed fairly high concentrations with medians of 320 Bq/kg for "2"2"6Ra, 64 Bq/kg for "2"3"2Th and 390 Bq/kg for "4"0K. The highest concentrations were however confined to specific areas of the mine. The effective dose due to gamma irradiation for the various areas of the mine was also estimated and the highest estimated level was 0.45 mSv/y. The article finally draws conclusions as to the origins and impact of the radiation. - Highlights: • A self-developed transportable and robust gamma ray detection system (the GISPI) was employed in the measurements. • A different mathematical analysis method was used. • QGIS was used extensively. • The results is important for current developments in infrastructure and mining.

  13. Comparative studies for determining U-235/U-238 relation in solutions of natural and depleted uranium using gamma spectrometry and neutron activation analysis

    International Nuclear Information System (INIS)

    Cassorla F, V.; Valle M, L.; Pena V, L.

    1988-01-01

    Two experimental methods were developed for determining U-235/U-238 ratio in uranium solutions. The isotopic was measured by high resolution ratio gamma-ray spectrometry (G.S.) and neutron activation analysis (N.A.A.). The precision obtained was similar for both methods, but better sensitivity was obtained by N.A.A. The accuracy in both cases was stablished by comparison with samples previously analyzed by mass spectrometry, the results were satisfactory for both techniques. Studies involving the influence of the nitric acid concentration on the isotopic ratio measurement, also were done. In addition, computer programs for faster data reduction were developped, in the case of N.A.A. (author)

  14. Use of airborne gamma-ray spectrometry for kaolin exploration

    Science.gov (United States)

    Tourlière, B.; Perrin, J.; Le Berre, P.; Pasquet, J. F.

    2003-08-01

    Airborne gamma-ray spectrometry was used to define targets with kaolin potential in the Armorican Massif of Brittany, France. This exploration method is based on the principle that kaolinite, an aluminosilicate clay mineral constituting kaolin, is formed by the hydrolysis of potash feldspar with the elimination of potassium. Therefore, potassium contrast between favourable host-rock such as a leucogranite and kaolin occurrence is likely a significant pathfinder. As the relationship between the potassium-40 recorded by an airborne gamma-ray spectrometer and total potassium is constant, such data provide us a direct measurement of the potassium content of the ground flown over. Our study tested this by calculating, for each geological unit, the difference between the measured and average potassium content calculated for a given geological formation. The study was based on (i) a recent (1998) high-definition airborne geophysical survey over the Armorican Massif undertaken on behalf of the French Government, and (ii) new geological compilation maps covering the same region. Depleted zones, where the measured potassium is less than the average potassium content calculated target areas with high potential of containing kaolin, provided that the unit was originally rich in potash feldspar. By applying this method to the entire Armorican Massif, it was possible to identify 150 potassium-depleted zones, including 115 that were subjected to rapid field checks and 36 that contained kaolin (21 new discoveries). This method, which is both safe for the environment and easy to use, is therefore a good tool for rapidly defining targets with kaolin potential at a regional scale. The method may also have possibilities in exploring for other types of deposit characterised by an enrichment or depletion in U, K and/or Th.

  15. Towards Molecular Characterization of Mineral-Organic Matter Interface Using In Situ Liquid Secondary Ion Mass Spectrometry

    Science.gov (United States)

    Zhu, Z.; Yu, X. Y.

    2017-12-01

    Organo-Mineral-Microbe interactions in terrestrial ecosystems are of great interest. Quite a few models have been developed through extensive efforts in this field. However, predictions from current models are far from being accurate, and many debates still exist. One of the major reasons is that most experimental data generated from bulk analysis, and the information of molecular dynamics occurring at mineral-organic matter interface is rare. Such information has been difficult to obtain, due to lack of suitable in situ analysis tools. Recently, we have developed in situ liquid secondary ion mass spectrometry (SIMS) at Pacific Northwest National Laboratory1, and it has shown promise to provide both elemental and molecular information at vacuum-liquid and solid-liquid interfaces.2 In this presentation, we demonstrate that in situ liquid SIMS can provide critical molecular information at solid substrate-live biofilm interface.3 Shewanella oneidensis is used as a model micro-organism and silicon nitride as a model mineral surface. Of particular interest, biologically relevant water clusters have been first observed in the living biofilms. Characteristic fragments of biofilm matrix components such as proteins, polysaccharides, and lipids can be molecularly examined. Furthermore, characteristic fatty acids (e.g., palmitic acid), quinolone signal, and riboflavin fragments were found to respond after the biofilm is treated with Cr(VI), leading to biofilm dispersal. Significant changes in water clusters and quorum sensing signals indicative of intercellular communication in the aqueous environment were observed, suggesting that they might result in fatty acid synthesis and inhibition of riboflavin production. The Cr(VI) reduction seems to follow the Mtr pathway leading to Cr(III) formation. Our approach potentially opens a new avenue for in-situ understanding of mineral-organo or mineral-microbe interfaces using in situ liquid SIMS and super resolution fluorescence

  16. Report of the Department of Energy, Office of Environmental Management, Gamma Spectrometry Data Validation Program

    International Nuclear Information System (INIS)

    Decker, K.; Sanderson, C.G.; Greenlaw, P.

    1996-11-01

    This report represents the results of analyses received on or before August 15, 1996 for the first annual Gamma Spectrometry Data Validation Program (May 1996) designed to assess the capability of DOE laboratories and DOE contractors in performing routine gamma spectra analyses. Data reduction of gamma spectra are normally performed with computer codes supplied by commercial manufacturers or are developed in house. Earlier evaluations of commercial codes gave spurious results for complex spectrum. A calibration spectrum, a background spectrum and three sample spectra of increasing complexity were included for each format. The calibration spectrum contained nuclides covering the energy range from 59.5 keV to 1836 keV. The first two samples contained fallout nuclides with halflives of over 30 days. Naturally occurring nuclides were also present. The third sample contained both short and long lived fission product nuclides. The participants were asked to report values and uncertainties as Becquerel per sample with no decay correction. Sixteen software packages were evaluated. In general, the results do not appear to be dependent on the software used. Based on the control limits established for the Program for the three sample spectra, 62%, 63% and 53%, respectively, of the reported results were evaluated as acceptable

  17. Optimization of a neural network model for signal-to-background prediction in gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Dragovic, S.; Onjia, A. . E-mail address of corresponding author: sdragovic@inep.co.yu; Dragovic, S.)

    2005-01-01

    The artificial neural network (ANN) model was optimized for the prediction of signal-to-background (SBR) ratio as a function of the measurement time in gamma-ray spectrometry. The network parameters: learning rate (α), momentum (μ), number of epochs (E) and number of nodes in hidden layer (N) were optimized simultaneously employing variable-size simplex method. The most accurate model with the root mean square (RMS) error of 0.073 was obtained using ANN with online backpropagation randomized (OBPR) algorithm with α = 0.27, μ 0.36, E = 14800 and N = 9. Most of the predicted and experimental SBR values for the eight radionuclides ( 226 Ra, 214 Bi, 235 U, 40 K, 232 Th, 134 Cs, 137 Cs and 7 Be), studied in this work, reasonably agreed to within 15 %, which was satisfactory accuracy. (author)

  18. Determination of the neutron activation profile of core drill samples by gamma-ray spectrometry.

    Science.gov (United States)

    Gurau, D; Boden, S; Sima, O; Stanga, D

    2018-04-01

    This paper provides guidance for determining the neutron activation profile of core drill samples taken from the biological shield of nuclear reactors using gamma spectrometry measurements. Thus, it provides guidance for selecting a model of the right form to fit data and using least squares methods for model fitting. The activity profiles of two core samples taken from the biological shield of a nuclear reactor were determined. The effective activation depth and the total activity of core samples along with their uncertainties were computed by Monte Carlo simulation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Comparison of laser fluorimetry, high resolution gamma-ray spectrometry and neutron activation analysis techniques for determination of uranium content in soil samples

    International Nuclear Information System (INIS)

    Ghods, A.; Asgharizadeh, F.; Salimi, B.; Abbasi, A.

    2004-01-01

    Much more concern is given nowadays for exposure of the world population to natural radiation especially to uranium since 57% of that exposure is due to radon-222, which is a member of uranium decay series. Most of the methods used for uranium determination is low concentration require either tedious separation and preconcentration or the accessibility to special instrumentation for detection of uranium at this low level. this study compares three techniques and methods for uranium analysis among different soil sample with variable uranium contents. Two of these techniques, neutron activation analysis and high resolution gamma-ray spectrometry , are non-destructive while the other, laser fluorimetry is done via chemical extraction of uranium. Analysis of standard materials is done also to control the quality and accuracy of the work. In spite of having quite variable ranges of detection limit, results obtained by high resolution gamma-ray spectrometry based on the assumption of having secular equilibrium between uranium and its daughters, which causes deviation whenever this condition was missed. For samples with reasonable uranium content, neutron activation analysis would be a rapid and reliable technique, while for low uranium content laser fluorimetry would be the most appropriate and accurate technique

  20. Gamma-ray spectrometry of ultra low levels of radioactivity within the material screening program for the GERDA experiment.

    Science.gov (United States)

    Budjás, D; Gangapshev, A M; Gasparro, J; Hampel, W; Heisel, M; Heusser, G; Hult, M; Klimenko, A A; Kuzminov, V V; Laubenstein, M; Maneschg, W; Simgen, H; Smolnikov, A A; Tomei, C; Vasiliev, S I

    2009-05-01

    In present and future experiments in the field of rare events physics a background index of 10(-3) counts/(keV kg a) or better in the region of interest is envisaged. A thorough material screening is mandatory in order to achieve this goal. The results of a systematic study of radioactive trace impurities in selected materials using ultra low-level gamma-ray spectrometry in the framework of the GERDA experiment are reported.

  1. Investigation by gamma-ray spectrometry and INAA of radioactivity impact on phosphate fertilizer plant environment

    International Nuclear Information System (INIS)

    Pantelica, A.; Companis, I.; Georgescu, I. I.; Pincovshi, E.

    2006-01-01

    The radioactive polluting effect of a phosphate fertilizer plant on the environment was investigated by gamma-ray spectrometry and neutron activation analysis (INAA). The hazards could arise from industrial plants using raw phosphate materials to prepare fertilizers for agricultural purposes due to the phosphate rock which, depending on the type and geographical zone of provenance may contain rather large amounts of uranium. The fertilizer plant under study is situated about 4 km from the town of Turnu Magurele, on the left bank of the Danube River in Romania. The main by-products of the factory are: nitro phosphate type fertilizers (NP, NPK), Ammonia, Nitric acid, Ammonium nitrate, Urea, Sulfuric acid, Phosphoric acid, Sodium fluorosilicate and Aluminum sulfate. Gamma-ray spectrometry was used to determine activity concentrations of naturally occurring radionuclides ( 2 26Ra, 2 35U, 2 38U, 2 32Th, and 4 0K), as well as 1 37Cs man-made radionuclide in surface soils collected from semicircular areas within radii of 0.5 and 15 km of the plant; in addition, different NPK type fertilizers and phosphate rocks were investigated. The samples (mass of about 100-g each) were kept tightly closed for one month to permit 2 26Ra to establish radioactive equilibrium with its decay products. This method makes it possible to assess U, Th, and K contents in samples by measuring 2 38U and 2 32Th (in equilibrium with their radioactive daughters) and 4 0K radioactivity, taken into account that 1 g of U, Th and K yield 1 2358 Bq 2 38U, 569 Bq 2 35U, 4057.2 Bq 2 32Th and 33.11 Bq 4 0K, respectively. The spectrometrical chain was based on a HPGe (EG and G Ortec) detector of 30 % relative efficiency and 2.1 keV resolution at 1332 keV of 6 0Co. INAA technique (neutron irradiation at TRIGA reactor of SCN Pitesti) was used to determine macro, micro and trace elements in samples collected from both technological shops of the factory (air dust and drinking tap water) and its surroundings

  2. In-situ γ spectrometry of the Chernobyl fallout using soil-sample independent corrections for surface roughness and migration

    International Nuclear Information System (INIS)

    Karlberg, O.

    1993-12-01

    The 661 keV gamma and 32 keV X-ray fluences from Cs-137 were measured in-situ with a Gamma-X Ge detector on different types of urban and rural surfaces. In comparison with a model calculation, the 661 keV fluence was used to estimate the surface activity assuming an ideal, infinite surface and the quotient between the 32 and 661 fluences was used to estimate the correction factors for the surfaces due to migration and surface roughness. As an alternative to the X-ray method, the use of a collimator for ordinary measurements of the 661 keV peak was analysed, and compared with the X-ray method and with measurements without a collimator. The X-ray method with the optimal soil distribution and composition gives the best results, but ordinary measurements with use of a collimator with a constant correction factor seems to be an appropriate method, when soil profiles for determination of a more exact calibration factor are not available

  3. Gamma ray fluorescence for in situ evaluation of ore in Witwatersrand gold mines

    International Nuclear Information System (INIS)

    Rolle, R.

    1979-01-01

    A system for quantitative in situ evaluation of ore in Witwatersrand gold mines was researched and subsequently developed. The principle of measurement is based on the excitation of gold K X-rays in rock face samples by the 88 keV gamma radiation from a Cadmium-109 radioisotope source. The X-rays and scattered radiation from the rock matrix are detected by a hyperpure germanium detector cooled by liquid nitrogen in a portable probe. In the fluorescence spectrum the intensity ratio of the gold Kβ peaks to their immediate scattered background is evaluated and quantitatively converted in the portable analyser to area concentration units. All aspects of the physical and instrumental measurement had to be investigated to arrive at a system capable of quantitative evaluation of trace concentrations in stope face ore samples. The parameters of spectrum evaluation were investigated from fundamental principles to allow quantitative assessment of different methods of peak evaluation for optimization of the method as a whole. The basic concepts of random signal processing times were developed together with new concepts of pileup parameters to allow a quantitative description of the data acquisition rate of a complete analog pulse processing system. With this foundation a practical measuring geometry and optimum values for signal processing time parameters, for detector size and for discriminator positions for spectrum evaluation could be determined. Parallel with the derivation of optimum measurement parameters went the development of instruments, their field testing and appraisal of the method. The development of the gamma ray fluorescence method has shown the potential of the method to serve as an ore valuation tool and to assist in the geological identification of strata in Witwatersrand gold mines

  4. Two-Step Resonance-Enhanced Desorption Laser Mass Spectrometry for In Situ Analysis of Organic-Rich Environments

    Science.gov (United States)

    Getty, S. A.; Grubisic, A.; Uckert, K.; Li, X.; Cornish, T.; Cook, J. E.; Brinckerhoff, W. B.

    2016-01-01

    A wide diversity of planetary surfaces in the solar system represent high priority targets for in situ compositional and contextual analysis as part of future missions. The planned mission portfolio will inform our knowledge of the chemistry at play on Mars, icy moons, comets, and primitive asteroids, which can lead to advances in our understanding of the interplay between inorganic and organic building blocks that led to the evolution of habitable environments on Earth and beyond. In many of these environments, the presence of water or aqueously altered mineralogy is an important indicator of habitable environments that are present or may have been present in the past. As a result, the search for complex organic chemistry that may imply the presence of a feedstock, if not an inventory of biosignatures, is naturally aligned with targeted analyses of water-rich surface materials. Here we describe the two-step laser mass spectrometry (L2MS) analytical technique that has seen broad application in the study of organics in meteoritic samples, now demonstrated to be compatible with an in situ investigation with technique improvements to target high priority planetary environments as part of a future scientific payload. An ultraviolet (UV) pulsed laser is used in previous and current embodiments of laser desorption/ionization mass spectrometry (LDMS) to produce ionized species traceable to the mineral and organic composition of a planetary surface sample. L2MS, an advanced technique in laser mass spectrometry, is selective to the aromatic organic fraction of a complex sample, which can provide additional sensitivity and confidence in the detection of specific compound structures. Use of a compact two-step laser mass spectrometer prototype has been previously reported to provide specificity to key aromatic species, such as PAHs, nucleobases, and certain amino acids. Recent improvements in this technique have focused on the interaction between the mineral matrix and the

  5. Developments in gamma-ray spectrometry: systems, software, and methods-II. 4. High-Performance Digital Gamma-Ray Spectrometry

    International Nuclear Information System (INIS)

    Michael Momayezi

    2001-01-01

    This paper reviews recent advances in the field of digital spectrometry made by researchers at X-Ray Instrumentation Associates. All XIA spectrometers are based on a core architecture, which employs digitizing the input signal without shaping and applying all basic data processing in real time to the digital data stream coming out of the wave form digitizer. The real-time digital data processing includes filtering, triggering, pileup rejection, and even pulse shape analysis. In this paper we will describe some of those methods that go beyond emulating a conventional analog system in a digital environment. Rather we will concentrate mainly on methods that have no real equivalent in the analog world. In conventional spectrometers pulse pileup recognition is hardwired and serves a single purpose, namely to reject signals that occur too close to each other to allow for a precise measurement of their amplitude. For a digital device, which can also record wave forms, that would be an unfortunate limitation. The study of very short-lived radioactive isotopes is a case in point. If such an isotope is implanted into a detector in which it then decays by charged particle emission, the signature for the sought-after isotope is that of an implant pulse followed by one or more decay pulses from the isotope and its daughters. If the decay products can be absorbed in the same detector channel, as is the case for proton and alpha emitters in a Si-strip detector, then the isotope decay will show up as a pulse train coming from that detector channel. The difficulty usually is to find the few isotopes of interest amongst a huge background of long-lived or stable isotopes. With programmable pileup recognition logic it is possible to trigger specifically on pulse trains, rather than single pulses, thereby picking out very selectively the isotopes of interest. Analyzing the pulse shape of the incoming preamplifier signal proves to be very useful in many applications. The most obvious

  6. Natural activity in Hudson River estuary samples and their influence on the detection limits for gamma emitting radionuclides using NaI gamma spectrometry

    International Nuclear Information System (INIS)

    Wrenn, M.E.; Jinks, S.M.; Hairr, L.M.; Paschoa, A.S.; Lentsch, J.W.

    1972-01-01

    Sources of natural radioactivity in Hudson River Estuary are described. The technique of analysis for gamma spectrometry of environmental samples is presented and its pros and cons discussed. The distribution of natural radioactivity in water, biota and sediment was reported as well as the role played by the vertical distribution of cesium-137 in sediments as an indicator of the rate of sedimentation. The effect of the presence of natural radionuclides on the detection limits of man-made nuclides in the Hudson River environment is thoroughly examined. The results obtained with a 4-in. sodium iodide well crystal housed in a low background mercury shielding compare favorably with a more sophisticated Ge(Li) system which uses anticoincidence, as far as the analysis of environmental samples is concerned. (U.S.)

  7. Open-source implementation of an algorithm for photopeaks search and analysis in gamma-ray spectrometry with semiconductor detectors

    International Nuclear Information System (INIS)

    Maduar, Marcelo F.; Pecequilo, Brigitte R.S.

    2009-01-01

    Radioactivity quantification of gamma-ray emitter radionuclides in samples measured by HPGe gamma spectrometers relies on the analysis of the photopeaks present in the spectra, especially on the accurate determination of their net areas. This paper presents a methodology and an algorithm description for the peak search and analysis in order to obtain the relevant peaks parameters and their uncertainties. The procedure is performed on a three step approach: a preliminary search is done by using the second-difference method; experimental peaks widths are assessed in order to obtain a width vs. channel relationship and to define regions with single or overlapping peaks; a non-linear fit is applied to each region of the spectrum with candidate peaks. The final target function is in the form G(x) = B(x) + F(x), where B(x) is the baseline composed by a sum of a weighed left-side B L (x) and right-side B R (x) base-line quadratic functions and the photopeaks term F(x) is a sum of Gaussian functions. The computational implementation is released entirely in open-source license. The code was developed in C++ language and the interface was developed with Qt GUI software toolkit. GNU scientific library, GSL, was employed to perform linear and non-linear fitting procedures as needed. Spectra previously generated at our laboratories were analyzed with the presented methodology and with the commercial software package WinnerGamma. Results obtained are consistent with those obtained with the aforementioned package, suggesting that it could be safely used in general-purpose gamma-ray spectrometry. (author)

  8. Possibility of applying the gamma-gamma method to the in situ determination of uranium-ore densities

    International Nuclear Information System (INIS)

    Czubek, J.; Guitton, J.

    1965-01-01

    The principles of the gamma-gamma method are reviewed. It is shown in particular that, under certain conditions, the method makes it possible to obtain a representative measurement of the electronic density. Chemical analyses have been carried out on samples obtained from uranium deposits. The results show that an exact correlation exists between the massive and electronic densities. It is possible to consider the possibility of measuring the density of uranium-containing rocks by the gamma-gamma method. (authors) [fr

  9. Iodine 129 measurements by gamma spectrometry in biological samples. Results in seaweeds (Fucus serratus et laminaria digitata)

    International Nuclear Information System (INIS)

    Maro, D.; Hebert, D.; Gandon, R.; Solier, L.

    1999-01-01

    A iodine selective radiochemistry method was developed to measure 129 I(period 1,57 x 10 10 7 years) by gamma spectrometry in biological samples. This method avoids using neutron activation analysis or accelerator mass spectrometry. The method is based on iodine extraction from samples in order to obtain an aqueous matrix with no attenuation agent except 127 I(stable isotope). The parallel determination of 127 I allows to correct 129 I measurements for self attenuation and also monitor seasonal changes in iodine metabolism in biological species. Measurements were performed in two seaweed species (Fucus serratus and Laminaria digitata) samples in the area of La Hague reprocessing plant discharge between January and February 1997). Samples from stations close to the point of release (Goury and Herquemoulin), showed 129 I activities around 60 Bq kg -1 dry weight in Fucus serratus and around 300 Bq kg -1 dry weight in Laminaria digitata. 300 km away from the realize point, 129 I activities were 10 Bq kg -1 dry weight in Fucus serratus and 171 Bq kg -1 dry weight in Laminaria digitata. 127 I concentrations were between 547 and 1,232 mg kg -1 dry weight in Fucus serratus and between 6,624 and 14,296 mg kg -1 dry weight in Laminaria digitata. (authors)

  10. Gamma ray doses proceeding from natural occurring radionuclides in closed environments

    International Nuclear Information System (INIS)

    Aguiar, Vitor Angelo P. de; Medina, Nilberto H.; Silveira, Marcilei A. Guazzelli da; Moreira, Ramon H.

    2009-01-01

    In this work we report on the application of gamma-ray spectrometry in the study of the effective dose coming from terrestrial natural elements present in building materials such as sand, cement, lime (CaO) and milled granitic stones. The major contribution to annual gamma-ray radiation effective dose is due to the natural occurring radionuclides 40 K, 232 Th and 238 U. Two spectrometry systems were employed to measure the gamma radiation: one with a 60% efficient GeHP detector and the second one with a 2''x2'' NaI(Tl) scintillator. The estimated effective dose coming from the three reference rooms assumed is 0.63 mSv/yr, proceeding from terrestrial natural elements. The principal gamma radiation sources are cement, sand and bricks. (author)

  11. Terrestrial gamma radiation baseline mapping using ultra low density sampling methods.

    Science.gov (United States)

    Kleinschmidt, R; Watson, D

    2016-01-01

    Baseline terrestrial gamma radiation maps are indispensable for providing basic reference information that may be used in assessing the impact of a radiation related incident, performing epidemiological studies, remediating land contaminated with radioactive materials, assessment of land use applications and resource prospectivity. For a large land mass, such as Queensland, Australia (over 1.7 million km(2)), it is prohibitively expensive and practically difficult to undertake detailed in-situ radiometric surveys of this scale. It is proposed that an existing, ultra-low density sampling program already undertaken for the purpose of a nationwide soil survey project be utilised to develop a baseline terrestrial gamma radiation map. Geoelement data derived from the National Geochemistry Survey of Australia (NGSA) was used to construct a baseline terrestrial gamma air kerma rate map, delineated by major drainage catchments, for Queensland. Three drainage catchments (sampled at the catchment outlet) spanning low, medium and high radioelement concentrations were selected for validation of the methodology using radiometric techniques including in-situ measurements and soil sampling for high resolution gamma spectrometry, and comparative non-radiometric analysis. A Queensland mean terrestrial air kerma rate, as calculated from the NGSA outlet sediment uranium, thorium and potassium concentrations, of 49 ± 69 nGy h(-1) (n = 311, 3σ 99% confidence level) is proposed as being suitable for use as a generic terrestrial air kerma rate background range. Validation results indicate that catchment outlet measurements are representative of the range of results obtained across the catchment and that the NGSA geoelement data is suitable for calculation and mapping of terrestrial air kerma rate. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  12. Validation of {sup 226}Ra, {sup 228}Ra and {sup 210}Pb measurements in soil and sediment samples through high resolution gamma ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Danila Carrijo da Silva; Silva, Nivaldo Carlos da; Bonifacio, Rodrigo Leandro; Guerrero, Eder Tadeu Zenun [Comissao Nacional de Energia Nuclear (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas

    2013-07-01

    Radionuclides found in ore extraction waste materials are a great source of concern regarding public health and environmental safety. One technique to determine the concentration of substances is high resolution gamma ray spectrometry using HPGe. Validating a measurement technique is essential to warrant high levels of quality to any scientific work. The Laboratory of Pocos de Caldas of the Brazilian Commission for Nuclear Energy partakes into a Quality Management System project, seeking Accreditation under ISO/IEC 17025 through the validation of techniques of chemical and radiometric analysis of environmental samples from water, soil and sediment. The focus of the Radon Laboratory at LAPOC is validation of Ra-226, Ra-228 and Pb-210 concentration determinations in soil and sediment through a gamma spectrometer system. The stages of this validation process included sample reception and preparation, detector calibration and sample analyses. Dried samples were sealed in metallic containers and analyzed after radioactive equilibrium between Ra-226 and daughters Pb-214 and Bi-214. Gamma spectrometry was performed using CANBERRA HPGe detector and gamma spectrum software Genie 2000. The photo peaks used for Ra-226 determination were 609 keV and 1020 keV of Bi-214 and 351 keV of Pb-214. For the Ra-228 determination a photopeak of 911 keV was used from its short half-life daughter Ac-228 (T1/2 = 6.12 h). For Pb-210, the photopeak of 46.5 keV was used, which, due to the low energy, self-absorption correction was needed. Parameters such as precision, bias/accuracy, linearity, detection limit and uncertainty were evaluated for that purpose. The results have pointed to satisfying results. (author)

  13. A rapid dissolution procedure to aid initial nuclear forensics investigations of chemically refractory compounds and particles prior to gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Reading, David G., E-mail: d.reading@noc.soton.ac.uk [GAU-Radioanalytical Laboratories, Ocean and Earth Science, University of Southampton, National Oceanography Centre, European Way, Southampton SO14 3ZH (United Kingdom); Croudace, Ian W.; Warwick, Phillip E. [GAU-Radioanalytical Laboratories, Ocean and Earth Science, University of Southampton, National Oceanography Centre, European Way, Southampton SO14 3ZH (United Kingdom); Britton, Richard [AWE plc, Aldermaston, Reading, Berkshire, RG7 4PR (United Kingdom)

    2015-11-05

    A rapid and effective preparative procedure has been evaluated for the accurate determination of low-energy (40–200 keV) gamma-emitting radionuclides ({sup 210}Pb, {sup 234}Th, {sup 226}Ra, {sup 235}U) in uranium ores and uranium ore concentrates (UOCs) using high-resolution gamma ray spectrometry. The measurement of low-energy gamma photons is complicated in heterogeneous samples containing high-density mineral phases and in such situations activity concentrations will be underestimated. This is because attenuation corrections, calculated based on sample mean density, do not properly correct where dense grains are dispersed within a less dense matrix (analogous to a nugget effect). The current method overcomes these problems using a lithium tetraborate fusion that readily dissolves all components including high-density, self-attenuating minerals/compounds. This is the ideal method for dissolving complex, non-volatile components in soils, rocks, mineral concentrates, and other materials where density reduction is required. Lithium borate fusion avoids the need for theoretical efficiency corrections or measurement of matrix matched calibration standards. The resulting homogeneous quenched glass produced can be quickly dissolved in nitric acid producing low-density solutions that can be counted by gamma spectrometry. The effectiveness of the technique is demonstrated using uranium-bearing Certified Reference Materials and provides accurate activity concentration determinations compared to the underestimated activity concentrations derived from direct measurements of a bulk sample. The procedure offers an effective solution for initial nuclear forensic studies where complex refractory minerals or matrices exist. It is also significantly faster, safer and simpler than alternative approaches. - Highlights: • Low energy gamma photons (<200 keV) are attenuated in U-bearing compounds. • Corrections based on bulk density do not yield accurate activity

  14. Study on the natural radioactivity from the region of Presidente Figueiredo (AM), Brazil, using gamma spectrometry; Estudo da radioatividade natural da regiao de Presidente Figueiredo (AM) utilizando espectrometria gama

    Energy Technology Data Exchange (ETDEWEB)

    Da Silva, Jose Ribamar Silveira

    1999-07-01

    A gamma spectrometry profile was carried out along BR174 highway, that crosses some lithostratigraphic units of the North portion of the Sedimentary Basin of Amazon. Measurements in situ were realized in 116 points, 1 km apart, using a GAD-6 gamma-spectrometer and samples of rocks and soils were collected in geologically representative points, for gamma measurements using a shielded detector of NaI(Tl) available in the Nuclear Geophysics Laboratory of IAG/USP. The criterion used for evaluating the reliability degree of the concentration values of eU (ppm), eTh (ppm) and %K was to establish mathematically detection limits, for all measurement points. Every these points had been located using GPS with accuracy of 50 m to become possible a future detailed study. The purpose of matching portable gamma spectrometer and laboratory determinations was to compare the 2 techniques, using the criterion of detectability limits, and to verify the influence of {sup 222} Rn atmospheric radioactive gas in field measurements. In the case of portable detector, it allows fast measurements and the sensor 'sees' a big volume of material (rock, soil...), that makes it more representative. In some situations where atmospheric phenomena of thermal inversion occurs, measurement can be affected by the {sup 222} Rn cosmic background. Presence of radon daughter elements, associated with aerosols, in this tropical environment (high values of temperature and humidity), where the speed of the wind that could exhaust this gas is practically zero. It is observed that the values of concentration in the some points, got with these 2 techniques, have the same trend, and the stretches where peaks of concentration of K also occur and U and Th are associated with the presence of granite out corps, great boulders, and clay soils from weathering of these rocks. (author)

  15. Study on the natural radioactivity from the region of Presidente Figueiredo (AM), Brazil, using gamma spectrometry; Estudo da radioatividade natural da regiao de Presidente Figueiredo (AM) utilizando espectrometria gama

    Energy Technology Data Exchange (ETDEWEB)

    Da Silva, Jose Ribamar Silveira

    1999-07-01

    A gamma spectrometry profile was carried out along BR174 highway, that crosses some lithostratigraphic units of the North portion of the Sedimentary Basin of Amazon. Measurements in situ were realized in 116 points, 1 km apart, using a GAD-6 gamma-spectrometer and samples of rocks and soils were collected in geologically representative points, for gamma measurements using a shielded detector of NaI(Tl) available in the Nuclear Geophysics Laboratory of IAG/USP. The criterion used for evaluating the reliability degree of the concentration values of eU (ppm), eTh (ppm) and %K was to establish mathematically detection limits, for all measurement points. Every these points had been located using GPS with accuracy of 50 m to become possible a future detailed study. The purpose of matching portable gamma spectrometer and laboratory determinations was to compare the 2 techniques, using the criterion of detectability limits, and to verify the influence of {sup 222} Rn atmospheric radioactive gas in field measurements. In the case of portable detector, it allows fast measurements and the sensor 'sees' a big volume of material (rock, soil...), that makes it more representative. In some situations where atmospheric phenomena of thermal inversion occurs, measurement can be affected by the {sup 222} Rn cosmic background. Presence of radon daughter elements, associated with aerosols, in this tropical environment (high values of temperature and humidity), where the speed of the wind that could exhaust this gas is practically zero. It is observed that the values of concentration in the some points, got with these 2 techniques, have the same trend, and the stretches where peaks of concentration of K also occur and U and Th are associated with the presence of granite out corps, great boulders, and clay soils from weathering of these rocks. (author)

  16. Automated complex for information retrieval and processing in the gamma-resonance spectrometry

    International Nuclear Information System (INIS)

    Belogurov, V.N.; Bylinkin, V.A.

    1977-01-01

    A complex for information retrieval and processing in the Moessbauer effect spectrometry is described. The complex consists of a set of 4 precision spectrometers nad a program system for the computation of Moessbauer effect spectrum. High velocity accuracy - 0.004 mm/s during 6 months operation is achieved by introducing an additional negative feedback, the signal from which is obtained when the time of electromagnetic vibrator driving rod passage in the middle of the cycle is compared to the half-period length of the operation of the multichannel analyser address register. Information from 4 spectrometers via a commutation unit and an equalizer unit is analyzed by one analyser. Descriptions and schemes of spectrometers, procedure and scheme of calibration and checking of their operation are given. Described are the system of connection of spectrometers with the BESM-4 computer and the program complex including programs of information input, check-up,, correction and storage in the computer, the calibration of the spectrometer velocity scale and the programs for computing gamma-resonance spectra. The description of the operational principles of these programs and their block diagrams is given

  17. Simultaneous Determination of 30 Trace Elements in Cancerous and Noncancerous Human Tissue Samples with Gamma-ray Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Samsahl, K; Brune, D; Wester, P O

    1963-10-15

    The following trace elements were quantitatively determined by gamma-ray spectrometry in T samples of non-cancerous and 5 samples of cancerous human tissue: P, Ca, Cr, Fe, Co, Cu, Zn, As, Se, Br, Rb, Mo, Ag, Cd, Sb, Cs, La, Au, and Hg. In some of the samples the following elements were qualitatively determined: Ti+Sc, Ga, Sr, In, Ba, Ce, Hf, Os, Pt, and U. Most of the trace elements were found to be present in much higher concentrations in the non-cancerous than in the corresponding cancerous liver samples. In a typical run one sample each of cancerous and non-cancerous tissue was irradiated together with standards of the elements to be determined in a thermal flux of 2.10{sup 13} n/cm{sup 2}/sec. for 24 hours. The radioactive trace elements were separated into 16, and in some cases 18, groups by means of a chemical group separation method. Subsequently, the gamma spectrometric measurements were performed. Two persons can manage the chemical separations and measure the different activities from a run in 1,5 days. A new method of comparing unknown samples with standards was developed.

  18. Solid state scintillators for gamma spectrometry

    International Nuclear Information System (INIS)

    La Mela, G.; Torrisi, M.

    1991-01-01

    Using different scintillator crystals, measurements of energy resolution and detection efficiency have been performed to detect gamma rays of energy ranging between 500 en 1550 KeV. This investigation is devoted to characterize the best systems to detect photons coming from positron annihilation processes, such as a PET apparatus where the medical image is the final aim of the investigation, and gamma emission from radioisotopes of biomedical interest

  19. Normal-Gamma-Bernoulli Peak Detection for Analysis of Comprehensive Two-Dimensional Gas Chromatography Mass Spectrometry Data.

    Science.gov (United States)

    Kim, Seongho; Jang, Hyejeong; Koo, Imhoi; Lee, Joohyoung; Zhang, Xiang

    2017-01-01

    Compared to other analytical platforms, comprehensive two-dimensional gas chromatography coupled with mass spectrometry (GC×GC-MS) has much increased separation power for analysis of complex samples and thus is increasingly used in metabolomics for biomarker discovery. However, accurate peak detection remains a bottleneck for wide applications of GC×GC-MS. Therefore, the normal-exponential-Bernoulli (NEB) model is generalized by gamma distribution and a new peak detection algorithm using the normal-gamma-Bernoulli (NGB) model is developed. Unlike the NEB model, the NGB model has no closed-form analytical solution, hampering its practical use in peak detection. To circumvent this difficulty, three numerical approaches, which are fast Fourier transform (FFT), the first-order and the second-order delta methods (D1 and D2), are introduced. The applications to simulated data and two real GC×GC-MS data sets show that the NGB-D1 method performs the best in terms of both computational expense and peak detection performance.

  20. Estimation of natural potassium concentration in Romanian males by in vivo gamma-ray spectrometry measurements

    International Nuclear Information System (INIS)

    Mirela Angela Saizu

    2012-01-01

    At the Whole Body Monitoring Laboratory, from IFIN-HH, Bucharest, Romania, there were performed in vivo gamma-ray spectrometry measurements on 108 Romanian males in order to evaluate the mineral natural potassium content in human body, as total value and concentration. The measurements were performed with a shadow shield whole body counter, tilted chair geometry, based on a shielded NaI(Tl) scintillation detector of 12.5 cm (diameter) x 10 cm (height) crystal size. The results revealed a calculated value of the mean total body potassium (TBK) of 135.03 ± 2.94 g and a value of 1.9 ± 0.022 g of potassium/kg of body weight for the mean body potassium concentration, for the measured males. These values are similar with the values declared for the Reference Man, in ICRP23. Correlations between total body potassium, potassium concentration and age, weight and Body Build Index were investigated and peculiar conclusions were resulted. (author)

  1. Study of principle error sources in gamma spectrometry. Application to cross sections measurement

    International Nuclear Information System (INIS)

    Majah, M. Ibn.

    1985-01-01

    The principle error sources in gamma spectrometry have been studied in purpose to measure cross sections with great precision. Three error sources have been studied: dead time and pile up which depend on counting rate, and coincidence effect that depends on the disintegration scheme of the radionuclide in question. A constant frequency pulse generator has been used to correct the counting loss due to dead time and pile up in cases of long and short disintegration periods. The loss due to coincidence effect can reach 25% and over, depending on the disintegration scheme and on the distance source-detector. After establishing the correction formula and verifying its validity for four examples: iron 56, scandium 48, antimony 120 and gold 196 m, an application has been done by measuring cross sections of nuclear reactions that lead to long disintegration periods which need short distance source-detector counting and thus correcting the loss due to dead time effect, pile up and coincidence effect. 16 refs., 45 figs., 25 tabs. (author)

  2. Airborne gamma spectrometry measurements in the context of the exercise ARM02

    International Nuclear Information System (INIS)

    Bucher, B.; Rybach, L.; Schwarz, G.; Baerlocher, C.

    2003-05-01

    The international exercise under the European Union project ECCOMAGS (European Coordination and Calibration of Mobile and Airborne Gamma Spectrometry) stood in the centre of the yearly airborne gamma spectrometry measurement flights which were carried out in the time of 27 -31 May 2002. The exercise was held in Southwest Scotland in the region of Dumfries and Galloway. Unfortunately due to difficulties with flight approvals for military aircrafts data could be taken in the exercise area only on the flight back to Switzerland. Immediately after returning to Switzerland the regular measurements around the nuclear power plants Beznau (KKB) and Leibstadt (KKL), around the intermediate storage facilities for radioactive waste (ZWILAG) and around the research facility Paul Scherrer Institute were performed. The flights took place in the context of the exercise ARM02 and were lead by the Swiss National Emergency Operations Centre (NAZ). Unfortunately just a few measurements in the common intercalibration areas could be taken on the flight back from the international exercise. Nevertheless comparisons of the results with those of other European teams could be made. These comparisons proved the good calibration of our equipment. On the flight back measurements were also carried out at great altitude above the sea. This data allowed to determine very well the background of the aircraft and the cosmic stripping ratios. In the context of the regular measurements in the environs of the nuclear facilities in Switzerland the areas around the nuclear power plants Beznau and Leibstadt and around the nuclear research facility Paul Scherrer Institute were measured. The results were very similar to the results of earlier measurements in the last years. The nuclear power plant Beznau couldn't be recognised on the activity maps. But the nuclear power plant Leibstadt could be identified by its direct radiation which is specific for this type of reactor (BWR). At the site of the Paul

  3. Application of fussy mathematics to the data processing of surface gamma spectrometry for gold exploration

    International Nuclear Information System (INIS)

    Huang Zheming.

    1990-01-01

    This paper introduces a new method by applying fuzzy mathematics to the data processing of uranium thorium and potassium, these data were detected from surface gamma spectrometry in the field and can be used to make quantitative interpretation for delineating gold mineralization in the favourable area. This method provides a rapid means for expanding and tracing gold deposits or occurrences and for prospecting gold deposits of the same kind and also provides an effective means for engineering design in uncovering exploration. It is of high efficiency, low cost and worth popularizing. It can be also used to look for other metallic and nonmetallic ore deposits

  4. Natural background gamma-ray spectrum. List of gamma-rays ordered in energy from natural radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Ichimiya, Tsutomu [Japan Radioisotope Association, Tokyo (Japan); Narita, Tsutomu; Kitao, Kensuke

    1998-03-01

    A quick index to {gamma}-rays and X-rays from natural radionuclides is presented. In the list, {gamma}-rays are arranged in order of increasing energy. The list also contains {gamma}-rays from radioactive nuclides produced in a germanium detector and its surrounding materials by interaction with cosmic neutrons, as well as direct {gamma}-rays from interaction with the neutrons. Artificial radioactive nuclides emitting {gamma}-rays with same or near energy value as that of the natural {gamma}-rays and X-rays are also listed. In appendix, {gamma}-ray spectra from a rock, uranium ore, thorium, monazite and uraninite and also background spectra obtained with germanium detectors placed in iron or lead shield have been given. The list is designed for use in {gamma}-ray spectroscopy under the conditions of highly natural background, such as in-situ environmental radiation monitoring or low-level activity measurements, with a germanium detector. (author)

  5. S100A7 (Psoriasin), highly expressed in Ductal Carcinoma In Situ (DCIS), is regulated by IFN-gamma in mammary epithelial cells

    International Nuclear Information System (INIS)

    Petersson, Stina; Bylander, Anna; Yhr, Maria; Enerbäck, Charlotta

    2007-01-01

    The aim of the present work was to explore signal transduction pathways used in the regulation of S100A7 (psoriasin). Members of the S100 gene family participate in many important cellular functions. Psoriasin, S100A8 (calgranulin A) and S100A9 (calgranulin B) are expressed in ductal carcinoma in situ (DCIS), as well as in the hyperproliferative skin disease, psoriasis. In the latter condition, a disturbance in the STAT pathway has recently been reported. This pathway is implicated in the regulation of IFN-gamma, widely recognized as a key cytokine in psoriasis. IFN-gamma also exerts anti-tumor action in a number of tumor cell types, including breast cancer. We therefore examined the effect of IFN-gamma and STAT-signaling on the psoriasin expression. We established a TAC2 mouse mammary epithelial cell line with tetracycline-inducible psoriasin expression (Tet-Off). Viability in cell culture was estimated using MTS assay. Protein and gene expression were evaluated by Western blotting and quantitative real-time PCR. Statistical analyses were assessed using a one-tailed, paired t-test. We report the downregulation of psoriasin by IFN-gamma in the MDA-MB-468 breast cancer cell line, as well as the downregulation of psoriasin induced by anoikis in cell lines derived from different epithelial tissues. In contrast, IFN-gamma had no suppressive effect on calgranulin A or calgranulin B. IFN-gamma is an important activator of the STAT1 pathway and we confirmed an active signaling pathway in the cell lines that responded to IFN-gamma treatment. In contrast, in the SUM190 breast carcinoma cell line, IFN-gamma did not suppress the expression of endogenous psoriasin. Moreover, a reduced phosphorylation of the STAT1 protein was observed. We showed that IFN-gamma treatment and the inhibition of the transcription factor NFkappaB had a synergistic effect on psoriasin levels. Finally, in TAC2 cells with tetracycline-induced psoriasin expression, we observed the increased viability of

  6. Compton suppression gamma ray spectrometry

    International Nuclear Information System (INIS)

    Landsberger, S.; Iskander, F.Y.; Niset, M.; Heydorn, K.

    2002-01-01

    In the past decade there have been many studies to use Compton suppression methods in routine neutron activation analysis as well as in the traditional role of low level gamma ray counting of environmental samples. On a separate path there have been many new PC based software packages that have been developed to enhance photopeak fitting. Although the newer PC based algorithms have had significant improvements, they still suffer from being effectively used in weak gamma ray lines in natural samples or in neutron activated samples that have very high Compton backgrounds. We have completed a series of experiments to show the usefulness of Compton suppression. As well we have shown the pitfalls when using Compton suppression methods for high counting deadtimes as in the case of neutron activated samples. We have also investigated if counting statistics are the same both suppressed and normal modes. Results are presented in four separate experiments. (author)

  7. The use of difference spectra with a filtered rolling average background in mobile gamma spectrometry measurements

    International Nuclear Information System (INIS)

    Cresswell, A.J.; Sanderson, D.C.W.

    2009-01-01

    The use of difference spectra, with a filtering of a rolling average background, as a variation of the more common rainbow plots to aid in the visual identification of radiation anomalies in mobile gamma spectrometry systems is presented. This method requires minimal assumptions about the radiation environment, and is not computationally intensive. Some case studies are presented to illustrate the method. It is shown that difference spectra produced in this manner can improve signal to background, estimate shielding or mass depth using scattered spectral components, and locate point sources. This approach could be a useful addition to the methods available for locating point sources and mapping dispersed activity in real time. Further possible developments of the procedure utilising more intelligent filters and spatial averaging of the background are identified.

  8. Urban gamma spectrometry. Report 1

    International Nuclear Information System (INIS)

    Aage, H.K.; Kuukankorpi, S.; Moring, M.; Smolander, P.; Toivonen, H.

    2009-06-01

    This report contains the present status and results for the NKS UGS-project per 1 June 2006 for NKS partners DTU, Denmark, and STUK, Finland. The Danish and Finnish CGS (Carborne Gamma Spectrometry) systems are not of similar types. The Danish CGS system(s) only make use of one NaI(Tl) detector whereas the Finnish CGS system consists of several detectors, NaI(Tl) and HPGe both and as an additional feature the Finnish detectors have position dependent different fields of view. Furthermore, the Finnish system is equipped with an air sampling system. In terms of operation, the Danish detector is located on the rooftop where as the Finnish detectors are located inside the vehicle. The Finnish and the Danish team use different methods for data processing. STUK uses a hypothesis test method to get robust real time alarms (within 10 seconds) when significant peaks from a previously defined set of nuclides are detected. An alarm for a significantly elevated total pulse rate is sent if none of the predefined nuclides is identified. All data are stored to the LINSSI database, which facilitates easy data retrieval for post processing. DEMA/DTU bases their calculations on full spectrum fitting using NASVD and the Danish software NucSpec. Source signals are found from spectrum fitting residuals or from stripping of energy windows - either by the standard 4-windows method or by a measurement based method where stripping factors for any window of interest can be derived from the measurements themselves. A thorough description of the two systems and data processing methods (including mathematics) are described in this report. For the Danish methods of data processing some comparisons have been made, but no final conclusion has been reached yet. Raw urban data has been investigated along with urban data sets to which source signals have been added and searched for. For the Finnish method calibration plots of the minimum detection limits for two different detector types have been

  9. Urban gamma spectrometry. Report 1

    Energy Technology Data Exchange (ETDEWEB)

    Aage, H K [Technical Univ. of Denmark, Kgs. Lyngby (Denmark); Kuukankorpi, S; Moring, M; Smolander, P; Toivonen, H [Radiation and Nuclear Safety Authority, Helsinki (Finland)

    2009-06-15

    This report contains the present status and results for the NKS UGS-project per 1 June 2006 for NKS partners DTU, Denmark, and STUK, Finland. The Danish and Finnish CGS (Carborne Gamma Spectrometry) systems are not of similar types. The Danish CGS system(s) only make use of one NaI(Tl) detector whereas the Finnish CGS system consists of several detectors, NaI(Tl) and HPGe both and as an additional feature the Finnish detectors have position dependent different fields of view. Furthermore, the Finnish system is equipped with an air sampling system. In terms of operation, the Danish detector is located on the rooftop where as the Finnish detectors are located inside the vehicle. The Finnish and the Danish team use different methods for data processing. STUK uses a hypothesis test method to get robust real time alarms (within 10 seconds) when significant peaks from a previously defined set of nuclides are detected. An alarm for a significantly elevated total pulse rate is sent if none of the predefined nuclides is identified. All data are stored to the LINSSI database, which facilitates easy data retrieval for post processing. DEMA/DTU bases their calculations on full spectrum fitting using NASVD and the Danish software NucSpec. Source signals are found from spectrum fitting residuals or from stripping of energy windows - either by the standard 4-windows method or by a measurement based method where stripping factors for any window of interest can be derived from the measurements themselves. A thorough description of the two systems and data processing methods (including mathematics) are described in this report. For the Danish methods of data processing some comparisons have been made, but no final conclusion has been reached yet. Raw urban data has been investigated along with urban data sets to which source signals have been added and searched for. For the Finnish method calibration plots of the minimum detection limits for two different detector types have been

  10. A new method for the determination of radionuclide distribution in the soil by in situ gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Zombori, P.; Andrasi, A.; Nemeth, I.

    1992-06-01

    A method was searched for to estimate the penetration characteristics of fallout radioactivity, using only spectral information obtained by in situ spectrometric measurements, and avoiding the need for long and tiresome sampling and sample analysis procedures. To speed up the analysis for depth distribution determination of fallout radioactivity in soil, an instrumental method based on the shape of spectra was developed. The ratio of peak to valley (the region between the photopeak and Compton edge) depends on the penetration of radionuclides in soil, providing an estimation of depth profile. These ratios were calculated and the method was tested by actual measurements. (R.P.) 7 refs.; 14 figs.; 2 tabs

  11. Burn-up measurements of spent fuel using gamma spectrometry technique

    International Nuclear Information System (INIS)

    Pereda, C.; Henriquez, C.; Klein, J.; Medel, J.

    2005-01-01

    Burn-up results obtained for HEU (45% of 235 U) fuel assemblies of the RECH-1 Research Reactor using gamma spectrometry technique are presented. The spectra were got from an in-pool facility built in the reactor to be mainly used to measure the burnup of irradiated fuel assemblies with short cooling time, where 95 Zr is being evaluated as possible fission monitor. A program to measure all spent fuel assemblies of the RECH-1 reactor was initiated in the frame of the Regional Project RLA/4/018: 'Management of Spent Fuel from Research Reactors'. The results presented here were obtained from HEU spent fuel assemblies with cooling time greater than 100 days and 137 Cs was used as fission monitor. The efficiency of the in-pool system was determined using a slightly burnt experimental fuel assembly, which has one fuel plate (one of the outer plates) and the rest are dummy plates. An average burn-up of 2.8% of 235 U was previously measured for the experimental fuel assembly utilizing a facility installed in a hot cell and 137 Cs was used as monitor. (author)

  12. Identification of early Llandovery (Silurian) anoxic palaeo-depressions at the western margin of the Murzuq Basin (southwest Libya), based on gamma-ray spectrometry in surface exposures

    Czech Academy of Sciences Publication Activity Database

    Fello, N.; Lüning, S.; Štorch, Petr; Redfern, J.

    2006-01-01

    Roč. 11, č. 3 (2006), s. 101-118 ISSN 1025-6059 R&D Projects: GA ČR GA205/99/1322 Institutional research plan: CEZ:AV0Z30130516 Keywords : postglacial anoxy * early Llandovery * Murzuq Basin * palaeo-depressions * gamma-spectrometry Subject RIV: DB - Geology ; Mineralogy

  13. Gamma radiation detectors for safeguards applications

    International Nuclear Information System (INIS)

    Carchon, R.; Moeslinger, M.; Bourva, L.; Bass, C.; Zendel, M.

    2007-01-01

    The IAEA uses extensively a variety of gamma radiation detectors to verify nuclear material. These detectors are part of standardized spectrometry systems: germanium detectors for High-Resolution Gamma Spectrometry (HRGS); Cadmium Zinc Telluride (CZT) detectors for Room Temperature Gamma Spectrometry (RTGS); and NaI(Tl) detectors for Low Resolution Gamma Spectrometry (LRGS). HRGS with high-purity Germanium (HpGe) detectors cooled by liquid nitrogen is widely used in nuclear safeguards to verify the isotopic composition of plutonium or uranium in non-irradiated material. Alternative cooling systems have been evaluated and electrically cooled HpGe detectors show a potential added value, especially for unattended measurements. The spectrometric performance of CZT detectors, their robustness and simplicity are key to the successful verification of irradiated materials. Further development, such as limiting the charge trapping effects in CZT to provide improved sensitivity and energy resolution are discussed. NaI(Tl) detectors have many applications-specifically in hand-held radioisotope identification devices (RID) which are used to detect the presence of radioactive material where a lower resolution is sufficient, as they benefit from a generally higher sensitivity. The Agency is also continuously involved in the review and evaluation of new and emerging technologies in the field of radiation detection such as: Peltier-cooled CdTe detectors; semiconductor detectors operating at room temperature such as HgI 2 and GaAs; and, scintillator detectors using glass fibres or LaBr 3 . A final conclusion, proposing recommendations for future action, is made

  14. Metoda pentru analiza spectrometrica cu detector de Ge(Li) a probelor de trasori radioactivi cu rasini schimbatoare de ioni

    International Nuclear Information System (INIS)

    Stanescu, S.P.; Farcasiu, O.M.

    1981-07-01

    The radioactive tracers methods presently in use in hydrology are based on ''in situ'' low resolution gamma-ray spectrometry measurements. However sometimes the information obtained in this way is not conclusive and the need for better spectrometry systems is evident. Therefore the authors present a method for measuring in laboratory conditions samples of radioactive tracers collected ''in situ'' and concentrated on ions exchange resins, sing low level gamma-ray spectrometry with Ge(Li) detector. The advantages of this method in comparison with the methods based on Na(Tl) detectors are also presented in the paper. (authors)

  15. In situ-observation of the vertical motion of soil waters by means of deuterated water using the gamma/neutron method: Laboratory and field

    International Nuclear Information System (INIS)

    Moutonnet, P.; Couchat, P.; Brissaud, F.; Puard, M.; Pappalardo, A.

    1978-01-01

    In order to study water movements in the field, the gamma/neutron method for measuring deuterated water was investigated. A laboratory device is presented which supplies measurements on 5 ml soil solution samples. A probe for in situ experiments is studied in all its performances: Background, calibration (count rate versus volumetric deuterated water content) and resolution. A dispersive transport of D 2 O pulses on soil column is presented and checked with a numerical simulation model. Then simultaneous measurement of soil water content and D 2 O concentration by neutron moisture gauge and gamma/neutron probe enable us to interpret the evolution of D 2 O pulse with an experimental field irrigation. (orig.) [de

  16. A low-energy set-up for gamma-ray spectrometry of NORM tailored to the needs of a secondary smelting facility

    OpenAIRE

    Lutter, Guilome; Vandael Schreurs, Indy; Croymans, Tom; Schroeyers, Wouter; Schreurs, Sonja; Hult, Mikael; Marissens, Gert; Stroh, Heiko; Tzikaa, Faidra

    2017-01-01

    A measurement station dedicated for quantitative radiological characterisation of naturally occurring radio-nuclides in a metallurgical company and based on gamma-ray spectrometry was developed. The station is intended for performing quality control of final non-ferrous metal products and for radiological checks of incoming materials. A low-background point-contact HPGe-detector was used and the signal was split in two branches to enable collecting simultaneously spectra with high amplificati...

  17. Geochemical interpretation of gamma-ray spectrometry images from the Achala granite (Cordoba, Argentina)

    International Nuclear Information System (INIS)

    Lopez, Luis E.

    1998-01-01

    Data of an old spectrometry gamma-ray survey carried out in the Sierras Pampeanas Range by the National Atomic Energy Commission (Argentina) were reprocessed to obtain a corrected digital archive. The geochemical interpretation of the 250 x 250 meters spectrometric grids from the Achala batholith area was based on the behaviour of the radioelements in a peraluminous magma. Spectrometric maps of potassium, uranium, thorium and their ratios were used. In particular, the Th grid was very useful to define the primary magmatic evolution of the granitoids. K and U correlate roughly with Th distribution. The observed positive correlation between Th and U is thought to be the result of surficial leaching of U from uraninite. Finally, U/Th ratio allows to determine both, the magmatic evolution of the rocks and the mineral phase responsible for U content. (author)

  18. Efficiency transfer using the GEANT4 code of CERN for HPGe gamma spectrometry.

    Science.gov (United States)

    Chagren, S; Tekaya, M Ben; Reguigui, N; Gharbi, F

    2016-01-01

    In this work we apply the GEANT4 code of CERN to calculate the peak efficiency in High Pure Germanium (HPGe) gamma spectrometry using three different procedures. The first is a direct calculation. The second corresponds to the usual case of efficiency transfer between two different configurations at constant emission energy assuming a reference point detection configuration and the third, a new procedure, consists on the transfer of the peak efficiency between two detection configurations emitting the gamma ray in different energies assuming a "virtual" reference point detection configuration. No pre-optimization of the detector geometrical characteristics was performed before the transfer to test the ability of the efficiency transfer to reduce the effect of the ignorance on their real magnitude on the quality of the transferred efficiency. The obtained and measured efficiencies were found in good agreement for the two investigated methods of efficiency transfer. The obtained agreement proves that Monte Carlo method and especially the GEANT4 code constitute an efficient tool to obtain accurate detection efficiency values. The second investigated efficiency transfer procedure is useful to calibrate the HPGe gamma detector for any emission energy value for a voluminous source using one point source detection efficiency emitting in a different energy as a reference efficiency. The calculations preformed in this work were applied to the measurement exercise of the EUROMET428 project. A measurement exercise where an evaluation of the full energy peak efficiencies in the energy range 60-2000 keV for a typical coaxial p-type HpGe detector and several types of source configuration: point sources located at various distances from the detector and a cylindrical box containing three matrices was performed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Detection of 210Pb in the lungs of smokers by in-vivo gamma spectrometry

    International Nuclear Information System (INIS)

    Berger, C.D.; Lane, B.H.

    1982-09-01

    Since mainstream smoke is highly enriched in 210 Pb, alpha radiation from inhaled cigarette smoke particles has been proposed as a cancer-producing agent in cigarette smokers. 210 Po and 210 Pb have been observed in tobacco, cigarette smoke and in the lungs of smokers. Since 210 Pb is highly enriched in mainstream smoke, there have been estimates of yearly excesses of 210 Pb in the lungs of one-pack-a-day smokers of 3 to 10 pCi (0.11 to 0.37 Bq). The ORNL Whole Body Counter was used to verify this estimate by the methodology of high-resolution, in vivo gamma spectrometry. Measurements were made on 113 adult male non-radiation workers who have either smoked at least one pack of cigarettes per day for at least five years, or have never smoked cigarettes. An analysis-of-variance table was generated based on the Pb-ratio for each individual which revealed that there was no statistically significant increase in the amount of 210 Pb in the lungs of smokers over those of non-smokers. Sources of error are also discussed

  20. Embedded gamma spectrometry: new algorithms for spectral analysis

    International Nuclear Information System (INIS)

    Martin-Burtart, Nicolas

    2012-01-01

    Airborne gamma spectrometry was first used for mining prospecting. Three main families were looked for: K-40, U-238 and Th-232. The Chernobyl accident acted as a trigger and for the last fifteen years, a lot of new systems have been developed for intervention in case of nuclear accident or environmental purposes. Depending on their uses, new algorithms were developed, mainly for medium or high energy signal extraction. These spectral regions are characteristics of natural emissions (K-40, U-238 and Th-232 decay chains) and fissions products (mainly Cs-137 and Co-60). Below 400 keV, where special nuclear materials emit, these methods can still be used but are greatly imprecise. A new algorithm called 2-windows (extended to 3), was developed. It allows an accurate extraction, taking the flight altitude into account to minimize false detection. Watching radioactive materials traffic appeared with homeland security policy a few years ago. This particular use of dedicated sensors require a new type of algorithms. Before, one algorithm was very efficient for a particular nuclide or spectral region. Now, we need algorithm able to detect an anomaly wherever it is and whatever it is: industrial, medical or SNM. This work identified two families of methods working under these circumstances. Finally, anomalies have to be identified. IAEA recommend to watch around 30 radionuclides. A brand new identification algorithm was developed, using several rays per element and avoiding identifications conflicts. (author) [fr

  1. Cooperation on Improved Isotopic Identification and Analysis Software for Portable, Electrically Cooled High-Resolution Gamma Spectrometry Systems Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Dreyer, Jonathan G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wang, Tzu-Fang [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Vo, Duc T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Funk, Pierre F. [Inst. for Radiological Protection and Nuclear Safety (IRSN), Fontenay-aux-Roses (France); Weber, Anne-Laure [Inst. for Radiological Protection and Nuclear Safety (IRSN), Fontenay-aux-Roses (France)

    2017-07-20

    Under a 2006 agreement between the Department of Energy (DOE) of the United States of America and the Institut de Radioprotection et de Sûreté Nucléaire (IRSN) of France, the National Nuclear Security Administration (NNSA) within DOE and IRSN initiated a collaboration to improve isotopic identification and analysis of nuclear material [i.e., plutonium (Pu) and uranium (U)]. The specific aim of the collaborative project was to develop new versions of two types of isotopic identification and analysis software: (1) the fixed-energy response-function analysis for multiple energies (FRAM) codes and (2) multi-group analysis (MGA) codes. The project is entitled Action Sheet 4 – Cooperation on Improved Isotopic Identification and Analysis Software for Portable, Electrically Cooled, High-Resolution Gamma Spectrometry Systems (Action Sheet 4). FRAM and MGA/U235HI are software codes used to analyze isotopic ratios of U and Pu. FRAM is an application that uses parameter sets for the analysis of U or Pu. MGA and U235HI are two separate applications that analyze Pu or U, respectively. They have traditionally been used by safeguards practitioners to analyze gamma spectra acquired with high-resolution gamma spectrometry (HRGS) systems that are cooled by liquid nitrogen. However, it was discovered that these analysis programs were not as accurate when used on spectra acquired with a newer generation of more portable, electrically cooled HRGS (ECHRGS) systems. In response to this need, DOE/NNSA and IRSN collaborated to update the FRAM and U235HI codes to improve their performance with newer ECHRGS systems. Lawrence Livermore National Laboratory (LLNL) and Los Alamos National Laboratory (LANL) performed this work for DOE/NNSA.

  2. Assessment of coal and ash environmental impact with the use of gamma- and X-ray spectrometry

    International Nuclear Information System (INIS)

    Kierzek, J.; Malozewska-Bucko, B.; Bukowski, P.; Parus, J.L.; Ciurapisnki, A.; Zaras, S.; Kunach, B.; Wiland, K.

    1999-01-01

    Gamma-ray spectrometry (GS), energy dispersive X-ray fluorescence (EDXRF) analysis methods and wavelength dispersive X-ray fluorescence (WDXRF) were applied for the studies of some coal components, e.g., sulphur, light and heavy metal element concentrations and naturally occurring radioactive isotope contents. Hundred fifty coal samples originating mostly from eight different coal mines from Upper Silesian Coal Basin and 150 samples of ash obtained from these coal samples in laboratory by total combustion at final temperature of 820 deg C, were analyzed. Such comparative analyses can be helpful in selection of most suitable kind of coal for burning in electrical power and heat plants to minimize the environmental pollution. (author)

  3. The application of computer technique in routine neutron activation analysis using high resolution gamma ray spectrometry

    International Nuclear Information System (INIS)

    Szopa, Z.; Plejewska, M.; Staszelis, J.

    1982-01-01

    A full system of four computer programs for routine - qualitative and quantitative - neutron activation analysis (NAA) using high resolution gamma ray-spectrometry had been elaborated. The structure and possibilities of the ''data flow'' programs i.e. programs DIDPDP and DIDCDC, dedicated for fast and reliable ''off line'' data transfer between the buffer memory of the spectrometric line (9-track magnetic tape) and the fast access memory (disc) of the used computers PDP-11/45 and CYBER-73 had been presented. The structure and organization of the ''data processing'' programs i.e. programs SAWAPS and MAZYG had been presented as well. The utility and reliability of these programs in the case of the large-scale, routine NAA, exampled by analysis of filters with air polutants, had been tested and discussed. Programs are written mainly in FORTRAN. (author)

  4. Quantification of 235U and 238U activity concentrations for undeclared nuclear materials by a digital gamma-gamma coincidence spectroscopy.

    Science.gov (United States)

    Zhang, Weihua; Yi, Jing; Mekarski, Pawel; Ungar, Kurt; Hauck, Barry; Kramer, Gary H

    2011-06-01

    The purpose of this study is to investigate the possibility of verifying depleted uranium (DU), natural uranium (NU), low enriched uranium (LEU) and high enriched uranium (HEU) by a developed digital gamma-gamma coincidence spectroscopy. The spectroscopy consists of two NaI(Tl) scintillators and XIA LLC Digital Gamma Finder (DGF)/Pixie-4 software and card package. The results demonstrate that the spectroscopy provides an effective method of (235)U and (238)U quantification based on the count rate of their gamma-gamma coincidence counting signatures. The main advantages of this approach over the conventional gamma spectrometry include the facts of low background continuum near coincident signatures of (235)U and (238)U, less interference from other radionuclides by the gamma-gamma coincidence counting, and region-of-interest (ROI) imagine analysis for uranium enrichment determination. Compared to conventional gamma spectrometry, the method offers additional advantage of requiring minimal calibrations for (235)U and (238)U quantification at different sample geometries. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  5. Computers in activation analysis and gamma-ray spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, B. S.; D' Agostino, M. D.; Yule, H. P. [eds.

    1979-01-01

    Seventy-three papers are included under the following session headings: analytical and mathematical methods for data analysis; software systems for ..gamma..-ray and x-ray spectrometry; ..gamma..-ray spectra treatment, peak evaluation; least squares; IAEA intercomparison of methods for processing spectra; computer and calculator utilization in spectrometer systems; and applications in safeguards, fuel scanning, and environmental monitoring. Separate abstracts were prepared for 72 of those papers. (DLC)

  6. Evaluation of In vitro and In vivo Performance of Granisetron In situ ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of various solvent systems and gamma irradiation on the in vitro and in vivo performance of granisetron HCl injectable phase-sensitive in situ forming implants (ISFIs). Methods: ISFIs were prepared by mixing and sterilized by gamma irradiation. Effect of solvent system was studied.

  7. Very little in situ produced radiocarbon retained in accumulating Antarctic ice

    NARCIS (Netherlands)

    Kemp, W.J.M. van der; Alderliesten, C.; Borg, K. van der; Holmlund, P.; Jong, A.F.M. de; Karlöf, L.; Lamers, R.A.N.; Oerlemans, J.; Thomassen, M.; Wal, R.S.W. van de

    2000-01-01

    Ice samples from Dronning Maud Land, Antarctica, were analyzed for 14CO2 and 14CO by accelerator mass spectrometry. Only a small amount (~2%) of in situ produced radiocarbon was detected. The calibrated radiocarbon ages, corrected for in situ produced 14C, are in fair agreement with age estimates

  8. Using multi spherical spectrometry for determination of dosimetric characteristics of mixed neutron and gamma radiation fields of fission sources

    International Nuclear Information System (INIS)

    Fyulep, M.; Nikodemova, D.; Grabovtsova, A.; Galan, P.; Trousil, J.

    1977-01-01

    Possibilities of the application of multispherical spectrometry in personnel dosimetry of neutrons (n) and gamma radiation (γ) are considered. Studies were made to elucidate a possibility of using albedo dosemeters to increase the sensitivity of personnel dosemeters. Determined were the dose due to the (n,γ) reaction in a human body, absorbed dose and dose equivalent. The effect of (n,γ) dose on the reading of personnel gamma dosemeter was considered. It is shown that the above effect on the dosemeter readings for frontal irradiation by a broad neutron beam in everyday personnel dosimetry near 252 Cf sources may be neglected. Only in the case of strongly slowed-down fission spectrum the effect of the (n,γ) reaction is considerable. The application of albedo dosemeter is expedient to take into account the corrections of personnel dosemeter readings [ru

  9. Gamma-emissions of some meteorites and terrestrial rocks. Evaluation of lunar soil radioactivity; Emissions gamma de quelques meteorites et roches terrestres. Evaluation de la radioactivite du sol lunaire

    Energy Technology Data Exchange (ETDEWEB)

    Nordemann, D. [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1966-07-01

    The gamma-emissions of some terrestrial rocks and of the following meteorites: Bogou, Eagle-Station, Granes, and Dosso were studied by quantitative low background gamma spectrometry. These measurements and their interpretation lead to the evaluation of the possible gamma-emissions of several models of lunar soils. (author) [French] Les emissions gamma des meteorites Bogou, Eagle-Station, Granes et Dosso et de quelques roches terrestres ont ete etudiees par spectrometrie gamma quantitative a faible mouvement propre. Ces mesures et leur interpretation permettent d'evaluer les principales contributions des emissions gamma du sol lunaire pour des modeles de compositions possibles variees. (auteur)

  10. Gamma-emissions of some meteorites and terrestrial rocks. Evaluation of lunar soil radioactivity; Emissions gamma de quelques meteorites et roches terrestres. Evaluation de la radioactivite du sol lunaire

    Energy Technology Data Exchange (ETDEWEB)

    Nordemann, D [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1966-07-01

    The gamma-emissions of some terrestrial rocks and of the following meteorites: Bogou, Eagle-Station, Granes, and Dosso were studied by quantitative low background gamma spectrometry. These measurements and their interpretation lead to the evaluation of the possible gamma-emissions of several models of lunar soils. (author) [French] Les emissions gamma des meteorites Bogou, Eagle-Station, Granes et Dosso et de quelques roches terrestres ont ete etudiees par spectrometrie gamma quantitative a faible mouvement propre. Ces mesures et leur interpretation permettent d'evaluer les principales contributions des emissions gamma du sol lunaire pour des modeles de compositions possibles variees. (auteur)

  11. Emergency response exercise of laboratories equipped with gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mala, Helena; Rulik, Petr; Jezkova, Tereza; Beckova, Vera [National Radiation Protection Institute (SURO), 140 00 Praha 28 (Czech Republic)

    2014-07-01

    At present 7 laboratories equipped with semiconductor gamma spectrometry (HPGe detectors) are included in the Radiation Monitoring Network (RMN) in the Czech Republic. These laboratories have 31 spectrometric chains and approximately 20 'experts' and 70 'users' who would guarantee measurements during a radiological emergency (RE). The stress exercise (a load test) was carried out in 4 of them. The aim was to test their measuring capacity in existing technical facilities and staff in the event of a RE and identify problems (bottlenecks) in the whole process from receipt of samples to entering the results into the central database of RMN. Duration of the exercise was 8 to 14 hours. Due to lack of staff, work in one 12-hour shift during a RE is presumed, which the laboratories should be able to provide for 14 days. Exercise samples covered a wide range of commodities that would probably come to the laboratories during RE (aerosol filters, adsorbed gaseous forms of iodine, fallout, surface and drinking waters, food chain components and soils). Some of the samples were previously spiked with {sup 85}Sr, {sup 88}Y and {sup 40}K (these nuclides represented actual nuclides that would occur in RE); soil samples contained higher values of {sup 137}Cs activity originating from the Chernobyl accident. Almost 40 employees took part in the exercise and measurements were carried out at 18 spectrometric chains. An automatic gamma counter which allows automatic operation of two HPGe detectors including the analysis of the spectra with a storage for up to 180 sample containers was operating in one of the laboratories involved in the exercise. The procedures in individual laboratories varied slightly depending on the staff and laboratory space available. During the exercise about 700 samples were evaluated; in addition, gamma-automat measured other 80 samples in the 'night shift'. 700 samples, this means 40 samples per a spectrometric chain or, from

  12. On-line interrogation of pebble bed reactor fuel using passive gamma-ray spectrometry

    Science.gov (United States)

    Chen, Jianwei

    The Pebble Bed Reactor (PBR) is a helium-cooled, graphite-moderated high temperature nuclear power reactor. In addition to its inherently safe design, a unique feature of this reactor is its multipass fuel cycle in which graphite fuel pebbles (of varying enrichment) are randomly loaded and continuously circulated through the core until they reach their prescribed end-of-life burnup limit (˜80,000--100,000 MWD/MTU). Unlike the situation with conventional light water reactors (LWRs), depending solely on computational methods to perform in-core fuel management will be highly inaccurate. As a result, an on-line measurement approach becomes the only accurate method to assess whether a particular pebble has reached its end-of-life burnup limit. In this work, an investigation was performed to assess the feasibility of passive gamma-ray spectrometry assay as an approach for on-line interrogation of PBR fuel for the simultaneous determination of burnup and enrichment on a pebble-by-pebble basis. Due to the unavailability of irradiated or fresh pebbles, Monte Carlo simulations were used to study the gamma-ray spectra of the PBR fuel at various levels of burnup. A pebble depletion calculation was performed using the ORIGEN code, which yielded the gamma-ray source term that was introduced into the input of an MCNP simulation. The MCNP simulation assumed the use of a high-purity coaxial germanium detector. Due to the lack of one-group high temperature reactor cross sections for ORIGEN, a heterogeneous MCNP model was developed to describe a typical PBR core. Subsequently, the code MONTEBURNS was used to couple the MCNP model and ORIGEN. This approach allowed the development of the burnup-dependent, one-group spectral-averaged PBR cross sections to be used in the ORIGEN pebble depletion calculation. Based on the above studies, a relative approach for performing the measurements was established. The approach is based on using the relative activities of Np-239/I-132 in combination

  13. In-situ suspended aggregate microextraction of gold nanoparticles from water samples and determination by electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Choleva, Tatiana G; Kappi, Foteini A; Tsogas, George Z; Vlessidis, Athanasios G; Giokas, Dimosthenis L

    2016-05-01

    This work describes a new method for the extraction and determination of gold nanoparticles in environmental samples by means of in-situ suspended aggregate microextraction and electrothermal atomic absorption spectrometry. The method relies on the in-situ formation of a supramolecular aggregate phase through ion-association between a cationic surfactant and a benzene sulfonic acid derivative. Gold nanoparticles are physically entrapped into the aggregate phase which is separated from the bulk aqueous solution by vacuum filtration on the surface of a cellulose filter in the form of a thin film. The film is removed from the filter surface and is dissociated into an acidified methanolic solution which is used for analysis. Under the optimized experimental conditions, gold nanoparticles can be efficiently extracted from water samples with recovery rates between 81.0-93.3%, precision 5.4-12.0% and detection limits as low as 75femtomolL(-1) using only 20mL of sample volume. The satisfactory analytical features of the method along with the simplicity indicate the efficiency of this new approach to adequately collect and extract gold nanoparticle species from water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Innovative Applications of In Situ Gamma Spectroscopy for Non-destructive Assay of Transuranic Wastes

    International Nuclear Information System (INIS)

    Watters, D.J.; Weismann, J.J.; Duke, S.J.; Nicosia, W.C.

    2009-01-01

    Cabrera Services (CABRERA), under contract to National Security Technologies, LLC (NSTec), supported the transuranic (TRU) waste reduction initiative at the Radioactive Waste Management Complex of the Nevada Test Site (NTS). CABRERA developed advanced NDA techniques for oversized boxes (OSB) and drums using in situ gamma spectroscopy during several phases of the project. A more thorough characterization method was employed during the planning phase of the project to better understand the TRU content and distribution within each container, while a comprehensive NDA program was designed and implemented during the intrusive phase that guided waste segregation and re-packaging of both TRU and low-level wastes (LLW). NSTec took receipt of 58 oversized boxes of suspect TRU waste from Lawrence Livermore National Lab (LLNL). TRU waste is defined as greater than 3.7 kilobecquerels per gram [kBq/g] (100 nanocuries (nCi)/g) activity from alpha-emitting radionuclides with atomic number greater than 92 having a half-life greater than 20 years. Each box was custom-made to house a variety of suspect TRU wastes resulting from years of weapons program research, development, and testing. Since their arrival at NTS, the boxes have undergone several iterations of non-destructive assay (NDA) in preparation for the comprehensive repackaging effort. NDA has included two rounds of in situ gamma spectroscopy and real-time radiography (RTR) scans that were videotaped. Contents have been confirmed to include glove boxes, HEPA filters and their housings, and assorted process equipment and piping. TRU content was determined via directly measuring plutonium-239 (Pu-239), americium-241 (Am-241), and other radionuclides, while adding calculated results for non-measurable nuclides using reliable scaling factors developed from acceptable knowledge (AK). Advantages of CABRERA's NDA methods included: - More NDA information is available in the same amount of counting time, allowing NSTec to make more

  15. Precision measurement of radioactivity in gamma-rays spectrometry using two HPGe detectors (BEGe-6530 and GC0818-7600SL models comparison techniques: Application to the soil measurement

    Directory of Open Access Journals (Sweden)

    Guembou Shouop Cebastien Joel

    2017-01-01

    • Proved that the activity concentration determination in gamma spectrometry depended on the energy range emitted by a radionuclide. This study showed that the standard deviation measurement was less important to the result realized with BEGe-6530 HPGe model. Our findings were demonstrated that the results of the Broad Energy Germanium detector were more reliable.

  16. Terrestrial gamma radiation baseline mapping using ultra low density sampling methods

    International Nuclear Information System (INIS)

    Kleinschmidt, R.; Watson, D.

    2016-01-01

    Baseline terrestrial gamma radiation maps are indispensable for providing basic reference information that may be used in assessing the impact of a radiation related incident, performing epidemiological studies, remediating land contaminated with radioactive materials, assessment of land use applications and resource prospectivity. For a large land mass, such as Queensland, Australia (over 1.7 million km 2 ), it is prohibitively expensive and practically difficult to undertake detailed in-situ radiometric surveys of this scale. It is proposed that an existing, ultra-low density sampling program already undertaken for the purpose of a nationwide soil survey project be utilised to develop a baseline terrestrial gamma radiation map. Geoelement data derived from the National Geochemistry Survey of Australia (NGSA) was used to construct a baseline terrestrial gamma air kerma rate map, delineated by major drainage catchments, for Queensland. Three drainage catchments (sampled at the catchment outlet) spanning low, medium and high radioelement concentrations were selected for validation of the methodology using radiometric techniques including in-situ measurements and soil sampling for high resolution gamma spectrometry, and comparative non-radiometric analysis. A Queensland mean terrestrial air kerma rate, as calculated from the NGSA outlet sediment uranium, thorium and potassium concentrations, of 49 ± 69 nGy h −1 (n = 311, 3σ 99% confidence level) is proposed as being suitable for use as a generic terrestrial air kerma rate background range. Validation results indicate that catchment outlet measurements are representative of the range of results obtained across the catchment and that the NGSA geoelement data is suitable for calculation and mapping of terrestrial air kerma rate. - Highlights: • A baseline terrestrial air kerma map of Queensland, Australia was developed using geochemical data from a major drainage catchment ultra-low density sampling program

  17. Quality assurance system in gamma spectrometry laboratory

    International Nuclear Information System (INIS)

    Mielnikow, A.; Michalik, B.; Chalupnik, S.; Lebecka, J.

    1996-01-01

    On basis of guidelines for development of QUALITY SYSTEM for a testing laboratory (European Standard Series EN 45000) a quality assurance system was implemented in gamma spectroscopy laboratory, where routine measurements of natural (mainly Ra-226, Ra-228, Ra-224, K-40) and artificial (mainly Cs-137 and Cs-134) isotopes are performed. We measure a variety of samples, but mainly coal, vaste rock, ashe, deposits, vegetation and air filters. Laboratory of gamma spectroscopy in Central Mining Institute has three HPGe detectors. There is one coaxial detector with 45% relative efficiency, one detector for low energy region and one detector with extended range). We have also two Ge(Li) detectors from former Czechoslovakia. Shielding is made mainly of steel (40 cm) with the interior covered with lead and copper. The electronics and software (Genie-PC) was bought at 'Canberra' and 'Silena'. The paper describes not only the system of quality assurance but also main problems met by its implementation and results of intercomparison measurements. The QAS has been introduced in 1992. In 1993 the Accreditation Certificate of Testing Laboratory for our Laboratory has been obtained from the Polish Bureau of Research and Certification as a fifth laboratory in Poland. (author)

  18. Low-resolution gamma-ray spectrometry for an information barrier based on a multi-criteria template-matching approach

    Energy Technology Data Exchange (ETDEWEB)

    Göttsche, Malte; Schirm, Janet; Glaser, Alexander

    2016-12-21

    Gamma-ray spectrometry has been successfully employed to identify unique items containing special nuclear materials. Template information barriers have been developed in the past to confirm items as warheads by comparing their gamma signature to the signature of true warheads. Their development has, however, not been fully transparent, and they may not be sensitive to some relevant evasion scenarios. We develop a fully open template information barrier concept, based on low-resolution measurements, which, by design, reduces the extent of revealed sensitive information. The concept is based on three signatures of an item to be compared to a recorded template. The similarity of the spectrum is assessed by a modification of the Kolmogorov–Smirnov test to confirm the isotopic composition. The total gamma count rate must agree with the template as a measure of the projected surface of the object. In order to detect the diversion of fissile material from the interior of an item, a polyethylene mask is placed in front of the detector. Neutrons from spontaneous and induced fission events in the item produce 2.223 MeV gamma rays from neutron capture by hydrogen-1 in the mask. This peak is detected and its intensity scales with the item's fissile mass. The analysis based on MCNP Monte Carlo simulations of various plutonium configurations suggests that this concept can distinguish a valid item from a variety of invalid ones. The concept intentionally avoids any assumptions about specific spectral features, such as looking for specific gamma peaks of specific isotopes, thereby facilitating a fully unclassified discussion. By making all aspects public and allowing interested participants to contribute to the development and benchmarking, we enable a more open and inclusive discourse on this matter.

  19. Radon fixation for determination of {sup 224}Ra, {sup 226}Ra and {sup 228}Ra via gamma-ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Herranz, M. [Departamento Ingenieria Nuclear y Mecanica de Fluidos, E. S. Ingenieros de Bilbao - Universidad del Pais Vasco (UPV/EHU), Alda. Urquijo s/n, 48013 Bilbao (Spain)]. E-mail: inphesom@bi.ehu.es; Idoeta, R. [Departamento Ingenieria Nuclear y Mecanica de Fluidos, E. S. Ingenieros de Bilbao - Universidad del Pais Vasco (UPV/EHU), Alda. Urquijo s/n, 48013 Bilbao (Spain); Abelairas, A. [Departamento Ingenieria Nuclear y Mecanica de Fluidos, E. S. Ingenieros de Bilbao - Universidad del Pais Vasco (UPV/EHU), Alda. Urquijo s/n, 48013 Bilbao (Spain); Legarda, F. [Departamento Ingenieria Nuclear y Mecanica de Fluidos, E. S. Ingenieros de Bilbao - Universidad del Pais Vasco (UPV/EHU), Alda. Urquijo s/n, 48013 Bilbao (Spain)

    2006-04-15

    The aim of this work is the improvement of the procedure for the determination of radium isotopes activities in water, which is done through radiochemical separation and subsequent gamma-ray spectrometry. In addition, radon gas retention is studied using different activated carbon materials. The results of the IAEA Proficiency test: 'Determination of radium and uranium radionuclides in water' of December 2002 [IAEA, 2003. Analytical quality control services: determination of radium and uranium radionuclides in water. Preliminary Report, Seibersdorf] are considered for this work.

  20. 40 K, 137 Cs and 232 Th activities in Brazilian milk samples measured by gamma ray spectrometry

    International Nuclear Information System (INIS)

    Melquiades, Fabio L.; Appoloni, Carlos R.

    2000-01-01

    This work deals with the measurement of radioactive activities in powdered milk, with high resolution gamma-ray spectrometry, using a HPGe detector coupled to a standard electronic nuclear chain and a multichannel card of 8192 channels. Preliminary measurements were accomplished to define the kind of the system shield, the geometry of the sample recipient, the size of the sampling and the self absorption correction. It was possible to measure the radionuclides 40 K, 137 Cs and 208 Tl, whose activities were calculated according to the International Atomic Energy Agency norms. The detector efficiency was measured employing calibrated samples, prepared with IAEA certificate standards mixed with powdered milk. Tukey's average comparison test was used to check the repeatability of the measurements and the absence of significant systematic deviation. (author)

  1. Determination of the Concentration of Radioactive Nuclides of Surface Soils of some Hadhramout's Valleys in Yemen Using Gamma-Ray Spectrometry

    International Nuclear Information System (INIS)

    Bazohair, A. O.; Bayashoot, A. K.; AL-Shamy, A. A.

    2004-01-01

    In this research five surface soil samples have been taken from some Hadhramout's valleys in Yemen (Khrid , Arf , Huwayrah , Buwaish, Khirba ) in the years from (1999) to (2002) and analyzed using gamma-ray spectrometry. The spectra of samples were measured using multichannel analyzer (MCA) that was connected with measurement system for this purpose.A high purity germanium(Hp Ge) detector with resolution of (2.11 keV) at gamma-line(1332 keV) of radioactive source(Co-60) used for detecting ( U 238 , Th 232 , K 40 , Cs 137 ) in the samples. The results showed that the average concentration of radioactive nuclides in the samples of uranium ranged from(37.56 Bq/Kg) to(46.58 Bq/Kg) and for thorium ranged from(37.93 Bq/Kg) to(47.28 Bq/Kg) and for potassium ranged from(347.57 Bq/Kg) to(850.10 Bq/Kg) and for cesium ranged from(6.94 Bq/Kg) to(15.86 Bq/Kg) and the measured precision of samples ranged from(4.71%) to (9.23%). (authors)

  2. Simultaneous determination of Ra-226, natural uranium and natural thorium by gamma-ray spectrometry INa(Ti), in solid samples

    International Nuclear Information System (INIS)

    Salvador, S.; Navarro, T.; Alvarez, A.

    1991-01-01

    A method has been developed to determine activities of Ra-226, natural uranium and natural thorium by gamma-ray spectrometry. The measurement system has been calibrated using standards specially prepared at the laboratory. It is necessary to assume secular equilibrium in the samples, between Ra-226 and Th-232 and its daughters nuclides, and between U-238 and its immediate daughter Th-234, as the photo peaks measured are those of the daughters. The results obtained indicate that this method can of ter replace the radiochemical techniques used to measure activities in this type of sample. The method has been successfully used to determine these natural isotopes in samples from uranium mills. (Author) 9 refs

  3. Prompt gamma-ray activation technique for in-situ analysis of mercury pollution in water

    International Nuclear Information System (INIS)

    Khouri, M.C.; Jayanthi, K.A.; Pascholati, P.R.

    1995-01-01

    Industrial and mining pollutants discharged into water are in general distributed homogeneously and we investigated a prompt neutron activation technique for the in-situ analysis, to start with of Hg content in water. The laboratory test employed a 252 Cf neutron source (of ∼ 3 x 10 6 n/s fluence) submerged in a test tank of water of ∼ 500 litres, and to monitor the gamma-ray emission a 4 x 4 NaI (Tl) detector system was employed. In 3000 is time interval trials, for a 46 ppm contamination level of Hg, we observed an excess of counts of ∼ 9.2 σ significance in the energy range of 4000-6500 keV, which can be attributed to the presence of mercury. This test system for a 10 hour monitoring can provide a minimum detectable sensitivity at 4.78 ppm. In the future experiments, we propose to replace the NaI(Tl) detector by a HPGe detector to facilitate simultaneous analyses of pollutants such as cadmium, chlorine, chromium etc for detection at few tenths to tens of ppm levels or better. (author). 5 refs., 2 figs., 2 tabs

  4. Recent Advances in Low-Level Nuclear Measurements at the CEA

    International Nuclear Information System (INIS)

    Mahe, C.; Lamadie, F.; Le Goaller, C.

    2009-01-01

    For several years the CEA has been performing nuclear measurements at different stages of decommissioning projects. The characterization tools initially developed for high-level radioactive waste analysis must be adapted to a new area of application: low-level measurements. Recent technical improvements in gamma imaging, gamma spectrometry detectors, and data analysis make it possible to provide relevant radiological data for waste management, as well as to develop robust and optimized decommissioning scenarios from the initial dose rate mapping to the final declared activity. These techniques have been implemented at various nuclear sites for both trial measurement campaigns and expert investigations to localize residual contamination, to identify the radioelements and to provide an accurate estimate of the declarable activity. Different types of measurements and devices have been used: gamma cameras, coded aperture techniques, alpha imaging prototypes, gamma spectrometry detectors (CdZnTe, HPGe, NaI, and LaBr 3 ), dose rate cartography, and calculation codes (Mercure, MCNP, etc.), all of which provide complementary data for radioactive waste categorization. This paper describes the latest developments and methods deployed on decommissioning projects focusing on low-level in situ applications. Waste drum characterization and in situ glove box measurements are discussed and the technologies and performance of gamma imaging systems, gamma spectrometry detectors, calculation codes and software are described. The paper concludes with a review of future developments and tests necessary for these applications. (authors)

  5. Preliminary Determination of Natural Radioactivity Levels of the State of Qatar using High-Resolution Gamma-ray Spectrometry

    International Nuclear Information System (INIS)

    Al-Sulaiti, H.A.; Regan, P.H.; Bradley, D.A.; Matthews, M.; Santawamaitre, T.; Malain, D.

    2009-01-01

    The State of Qatar is a peninsula with a total area of 11,437 km 2 which lies over a geological formation comprising a sequence of limestone, chalk, clay and gypsum. Establishing a baseline for the radioactivity concentration in Qatar's soil is the main purpose behind the present study. The project is focused on obtaining measurements of representative soil samples from various areas in Qatar to establish concentrations of the 235 U, 238 U and 232 Th natural decay chains and also the long-lived naturally occurring radionuclide 40 K. The 235 U, 238 U, 232 Th and 40 K concentrations have been measured via high-resolution gamma-ray spectrometry using a hyper-pure germanium detector situated in a low-background environment with a copper inner-plated passive lead shield. A wide range of different gamma-ray energy transitions lines arising from the multiple decay products from the 235 U, 238 U and 232 Th decay chains have been analyzed separately to obtain more statistically significant overall results

  6. Automated gamma spectrometry and data analysis on radiometric neutron dosimeters

    International Nuclear Information System (INIS)

    Matsumoto, W.Y.

    1983-01-01

    An automated gamma-ray spectrometry system was designed and implemented by the Westinghouse Hanford Company at the Hanford Engineering Development Laboratory (HEDL) to analyze radiometric neutron dosimeters. Unattended, automatic, 24 hour/day, 7 day/week operation with online data analysis and mainframe-computer compatible magnetic tape output are system features. The system was used to analyze most of the 4000-plus radiometric monitors (RM's) from extensive reactor characterization tests during startup and initial operation of th Fast Flux Test Facility (FFTF). The FFTF, operated by HEDL for the Department of Energy, incorporates a 400 MW(th) sodium-cooled fast reactor. Aumomated system hardware consists of a high purity germanium detector, a computerized multichannel analyzer data acquisition system (Nuclear Data, Inc. Model 6620) with two dual 2.5 Mbyte magnetic disk drives plus two 10.5 inch reel magnetic tape units for mass storage of programs/data and an automated Sample Changer-Positioner (ASC-P) run with a programmable controller. The ASC-P has a 200 sample capacity and 12 calibrated counting (analysis) positions ranging from 6 inches (15 cm) to more than 20 feet (6.1 m) from the detector. The system software was programmed in Fortran at HEDL, except for the Nuclear Data, Inc. Peak Search and Analysis Program and Disk Operating System (MIDAS+)

  7. Detection of /sup 210/Pb in the lungs of smokers by in-vivo gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Berger, C.D.; Lane, B.H.

    1982-09-01

    Since mainstream smoke is highly enriched in /sup 210/Pb, alpha radiation from inhaled cigarette smoke particles has been proposed as a cancer-producing agent in cigarette smokers. /sup 210/Po and /sup 210/Pb have been observed in tobacco, cigarette smoke and in the lungs of smokers. Since /sup 210/Pb is highly enriched in mainstream smoke, there have been estimates of yearly excesses of /sup 210/Pb in the lungs of one-pack-a-day smokers of 3 to 10 pCi (0.11 to 0.37 Bq). The ORNL Whole Body Counter was used to verify this estimate by the methodology of high-resolution, in vivo gamma spectrometry. Measurements were made on 113 adult male non-radiation workers who have either smoked at least one pack of cigarettes per day for at least five years, or have never smoked cigarettes. An analysis-of-variance table was generated based on the Pb-ratio for each individual which revealed that there was no statistically significant increase in the amount of /sup 210/Pb in the lungs of smokers over those of non-smokers. Sources of error are also discussed.

  8. Assessment of ambient gamma dose rate around a prospective uranium mining area of South India - A comparative study of dose by direct methods and soil radioactivity measurements

    Science.gov (United States)

    Karunakara, N.; Yashodhara, I.; Sudeep Kumara, K.; Tripathi, R. M.; Menon, S. N.; Kadam, S.; Chougaonkar, M. P.

    Indoor and outdoor gamma dose rates were evaluated around a prospective uranium mining region - Gogi, South India through (i) direct measurements using a GM based gamma dose survey meter, (ii) integrated measurement days using CaSO4:Dy based thermo luminescent dosimeters (TLDs), and (iii) analyses of 273 soil samples for 226Ra, 232Th, and 40K activity concentration using HPGe gamma spectrometry. The geometric mean values of indoor and outdoor gamma dose rates were 104 nGy h-1 and 97 nGy h-1, respectively with an indoor to outdoor dose ratio of 1.09. The gamma dose rates and activity concentrations of 226Ra, 232Th, and 40K varied significantly within a small area due to the highly localized mineralization of the elements. Correlation study showed that the dose estimated from the soil radioactivity is better correlated with that measured directly using the portable survey meter, when compared to that obtained from TLDs. This study showed that in a region having localized mineralization in situ measurements using dose survey meter provide better representative values of gamma dose rates.

  9. Software for nuclear spectrometry

    International Nuclear Information System (INIS)

    1998-10-01

    The Advisory Group Meeting (AGM) on Software for Nuclear Spectrometry was dedicated to review the present status of software for nuclear spectrometry and to advise on future activities in this field. Because similar AGM and consultant's meetings had been held in the past; together with an attempt to get more streamlined, this AGM was devoted to the specific field of software for gamma ray spectrometry. Nevertheless, many of the issues discussed and the recommendations made are of general concern for any software on nuclear spectrometry. The report is organized by sections. The 'Summary' gives conclusions and recommendations adopted at the AGM. These conclusions and recommendations resulted from the discussions held during and after presentations of the scientific and technical papers. These papers are reported here in their integral form in the following Sections

  10. On self-attenuation corrections in gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Bolivar, J.P.; Garcia-Leon, M.; Garcia-Tenorio, R.

    1997-01-01

    In this paper we discuss and justify the dependence on the sample density and gamma energy of the self-attenuation correction factor, f, in the transmission method for the full energy peak efficiency calibration of Ge detectors. It is suggested as a method for the direct computing of f in the case that the sample composition is known. (Author)

  11. Application of gamma-spectrometry to post irradiation examination

    International Nuclear Information System (INIS)

    Kim, S.K.; Huh, Y.H.; Park, K.J.

    1982-01-01

    A areat variety of nuclear gamma rays emitted from fission and activation products of spent nuclear fuel contains much information that can be elicited without affecting the integrity of the fuel elements. In the present work, a versatile code CAERI was developed which locates peaks and calculates their areas for X-rays as well as gamma rays using elegant features of some widely used programs for gamma ray peak fitting. CAERI coded in FORTRAN used infinite series approximation more accurate than other workers' various, simple, piecewise series approximations for evaluation of the Voigt function which represents the X-ray peak with nonneglible natural line width. CAERI can handle even a complex multiplet consisting of peaks from X-rays and rays in arbitrary mixture, which one often encounters in the isotopic analysis of heavy elements such as U and Pu. (Author)

  12. In-Situ Compositional Analysis and Provenance Study of the Historic Terengganu Stone (“Batu Bersurat Piagam Terengganu”) Using Neutron-Induced Prompt Gamma-Ray Techniques

    International Nuclear Information System (INIS)

    Abdullah, J.; Yahya, R.; Dahing, N. S.; Shaari, M. R.; Mahmood, A. A.; Hassan, H.; Jamaluddin, T. A.; Abdullah, M. Y.; Mahmud, N. A.; Mosorov, V.

    2018-01-01

    Terengganu inscribed stone is the oldest artifact with Jawi writing on it. It is a most treasured heritage for the history of Malaysian civilisation. The artifact proves that the Kingdom of Terengganu exist earlier than 1326 or 1386. It was accidentally discovered near Tersat River at Kampong Buluh, Kuala Berang, Terengganu, Malaysia by a gold & tin trader after a flash flood hit Kuala Berang in 1902.The inscription turned out to be a proclamation issued by the ''Sri Paduka Tuan'' of Terengganu. The significant is the date on the first face of the inscription, which is given as the year 1303 AD. This project focuses on the development of in-situ compositional analysis and provenance study of the Inscribed Terengganu Stone using Neutron-Induced Prompt Gamma-Ray Techniques (NIPGAT). To date, a lot of studies have been carried out by historians and archaeologists about the content of the inscription, but no scientific investigation about the material composition and its provenance has been performed. In this project, an instrumental analysis NIPGAT was designed as a portable non-destructive investigation tool employing an isotopic neutron source (Cf-252) and a gamma-ray spectroscopy system for in-situ investigation of the Inscribed Stone. (author)

  13. In situ gamma-ray spectrometric measurements of uranium in phosphates soil

    International Nuclear Information System (INIS)

    Lavi, N.; Ne'eman, E.; Brenner, S.; Haquin, G.; Nir-El, Y.

    1997-01-01

    Abstract Radioactivity concentration of 238 U in a phosphate ores quarry was measured in situ. Independently, soil samples collected in the site were measured in the laboratory. It was disclosed that radon emanation from the soil lowers in situ results that are derived from radon daughters. Uranium concentration was found to be 121.6±1.9 mg kg -1 (authors)

  14. An analysis of the potassium concentrations of soft drinks by HPGe gamma spectrometry

    International Nuclear Information System (INIS)

    Guillermo Espinosa; Jose-Ignacio Golzarri; Ilsa Hernandez-Ibinarriaga

    2009-01-01

    Potassium, in a variety of compounds, occurs in abundance in the Earth's crust, and is an essential nutrient for human health. A naturally occurring radioactive isotope of potassium, 40 K, is found in the food and water that we consume. This paper presents the results of a gamma spectrometry analysis of the 40 K concentrations of a selection of commercial soft drinks. The 40 K concentrations are used to calculate the overall potassium concentrations. The analysis was carried out using a hyper-pure germanium (HPGe) detector with Ortec R ASPEC-927 multichannel analyzer module and GammaVision R software. This system was chosen for its high resolution and automatic data processing. The carbonated soft drinks (sodas) Coca-Cola R , Coca-Cola Light R (sold as Diet Coke R in the USA and other countries), Coca-Cola Zero R , Pepsi R , Pepsi Light R , Pepsi Max R , Big Cola R , Lulu-Cola R , Manzana Lift R , Sprite R and Fanta R and the mineral waters Ciel R and Penafiel R were analyzed. These brands are all international registered trademarks. The products analyzed were manufactured and bottled in Mexico. The results show a great variety of potassium concentrations in the different soft drinks analyzed (from 128.0 to 1113.1 mg/L). The concentration of potassium in the sodas, in conjunction with the amounts drank by one person in a year (180 L/year), are high enough to warrant consideration by public health authorities and by people to whom high potassium intakes pose a risk. (author)

  15. In situ gamma-ray spectrometric analysis of radionuclide distributions at a commercial shallow land burial site

    International Nuclear Information System (INIS)

    Kirby, L.J.; Campbell, R.M.

    1984-10-01

    Gamma-ray spectrometric analysis conducted at the Maxey Flats, Kentucky (USA) shallow land burial site confirmed that the waste radionuclides have been retained largely within the restricted area of the burial site. Concentrations of 137 Cs and 60 Co were comparable with those originating from global fallout and lower than concentrations measured in several other areas having similar rainfall. In-situ spectrometric analyses, corroborated by soil sample and vegetation analyses, indicate that the site has influenced 60 Co levels slightly in the west drainage channel, but 137 Cs did not originate from the site. Concentrations of 60 Co, 90 Sr and 137 Cs determined in subsurface soils by well logging techniques confirmed that subsurface migration of waste-derived radionuclides to points outside the restricted area has not been a significant source of contamination of the environs adjacent to the site. 8 references, 8 figures

  16. Optimum method to determine radioactivity in large tracts of land. In-situ gamma spectroscopy or sampling followed by laboratory measurement

    International Nuclear Information System (INIS)

    Bronson, Frazier

    2008-01-01

    In the process of decommissioning contaminated facilities, and in the conduct of normal operations involving radioactive material, it is frequently required to show that large areas of land are not contaminated, or if contaminated that the amount is below an acceptable level. However, it is quite rare for the radioactivity in the soil to be uniformly distributed. Rather it is generally in a few isolated and probably unknown locations. One way to ascertain the status of the land concentration is to take soil samples for subsequent measurement in the laboratory. Another way is to use in-situ gamma spectroscopy. In both cases, the non-uniform distribution of radioactivity can greatly compromise the accuracy of the assay, and makes uncertainty estimates much more complicated than simple propagation of counting statistics. This paper examines the process of determining the best way to estimate the activity on the tract of land, and gives quantitative estimates of measurement uncertainty for various conditions of radioactivity. When the distribution of radioactivity in the soil is not homogeneous, the sampling uncertainty is likely to be larger than the in-situ measurement uncertainty. (author)

  17. Application of full spectrum analysis technique for NaI(TI) based gamma ray spectral monitoring system

    International Nuclear Information System (INIS)

    Pant, Amar D.; Verma, Amit K.; Narayani, K.; Anilkumar, S.; Singh, Rajvir

    2016-01-01

    NaI(Tl) is commonly used for the gamma spectrometry analysis in laboratories. It continues to be the first choice for gamma spectrometry in many applications even today. Many gamma spectrometric methods are developed to experimentally determine activity of radionuclides in samples. Detectors used worldwide for gamma radiation monitoring are either GM based or scintillator based detector based on count rate. For radiation early warning systems radionuclide specific radiation monitoring methodology is required i.e. gamma ray spectrometry based environmental monitoring system. A computer program has been developed for gamma spectral monitoring by the use of full spectrum analysis (FSA). In this measured spectra are fitted using individual spectral components by least square fitting (LSF). The method is found very useful in situations, where radionuclide specific environmental radiation monitoring is required. The paper describes the details of the FSA procedure for the on line acquisition and analysis of gamma ray spectra from Nal(Tl) detectors

  18. Detection and evaluation of uranium in different minerals by gamma spectrometry and laser induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Sergani, F.M.; Khedr, M.A.; Harith, M.A.; El Mongy, S.A.

    2004-01-01

    Analysis, detection and evaluation of source nuclear materials (e.g. uranium) in different minerals by sensitive techniques are a vital objective for uranium exploration, nuclear materials extraction, processing and verification. In this work, uranium in different geological formations was determined using gamma spectrometry and laser induced breakdown spectroscopy (LIBS). The investigated samples were collected from different regions distributed all over Egypt. The samples were then prepared for non-destructive analysis. A hyper pure germanium detector was used to measure the emitted gamma rays of uranium and its daughters in the samples. The concentrations of uranium in ppm (μg/g) in the investigated samples are given and discussed in this work. The highest uranium concentration (4354.9 ppm) was found in uranophane samples of Gattar rocks. In Laser induced breakdown spectroscopy (LIBS) technique, plasma was formed by irradiating the rock surface with focused Q-switched Nd:Yag laser pulses of 7 ns pulse duration at the fundamental wavelength (1064 nm). Atoms and ions originating from the rock surface are excited and ionized in the laser produced hot plasma (∝10 000 K). The plasma emission spectral line is characteristic of the elements present in the plasma and allows identification of the uranium in the uranophane mineral. The strong atomic line at 424.2 nm is used for the qualitative identification of uranium. It can be mentioned that the elevated levels of uranium in some of the investigated uranophane samples are of great economic feasibility to be extracted. (orig.)

  19. {sup 129}I determination by direct Ge gamma-X spectrometry and its application to the concentration variation in two seaweed species

    Energy Technology Data Exchange (ETDEWEB)

    Barker, E.; Bouisset, P. [Institut de Radioprotection et de Surete Nucleaire (IRSN), Environmental Radioactivity Measurement Lab., 91 - Orsay (France); Masson, M.; Germain, P. [Institut de Radioprotection et de Surete Nucleaire (IRSN), Octeville-Cherbourg Radioecology Lab., 50 - Octeville -Cherbourg (France); Siclet, F. [Electricite de France (EDF), 78 - Chatou (France)

    2004-07-01

    The quantification of radionuclides by direct Ge gamma-X spectrometry with energy below 100 keV requires the elementary composition knowledge of the sample or the development of a device for determining the mass attenuation coefficients. This is especially true for {sup 129}I which is characterised by a 29.7 keV X-ray and 39.6 keV gamma ray. An experimental equipment has been developed in order to obtain this mass attenuation coefficient as a function of the energy. The elementary composition of a sample could change according to the biological phase of the organism and the sample preparation. {sup 129}I concentrations have been measured in samples of seaweed (Fucus serratus and Laminaria digitata) collected monthly during one year nearby La Hague reprocessing plant. Its quantification in different parts of these seaweeds was also performed in order to study the activity distribution. This paper will present measurement methodology used for {sup 129}I determination and its concentration variations during one-year period and the organo-tropism of {sup 129}I in the two seaweeds. (author)

  20. The metrological activity determination of 238 U and 230 Th by gamma spectrometry to industrial fuel-cycle application

    International Nuclear Information System (INIS)

    Almeida M, M.C. de; Delgado, J.U.; Poledna, R.

    2006-01-01

    This work describes the difficulty for determining the activity of 238 U and 230 Th using gamma spectrometry due to the low gamma-ray emission probabilities of 92 and 67 keV, and, mainly, the associated high uncertainties about 13 and 11%, respectively. 230 Th is a 238 U daughter and it is product from uranium mills and refineries. 230 Th decays to 226 Ra and this decay has to be measured because these radionuclides are not in secular equilibrium with their daughter products, besides the gamma-energies have high uncertainties in the emission probabilities. These radionuclides, mostly 238 U, are important in the nuclear fuel-cycle, since the mining of uranium ore, where the nominal isotopic content of natural uranium is 99.27% of 238 U, until the irradiated fuel reprocessing, where this isotope, a fertile material, is recovered to be used again. The uranium and thorium are considered safeguarded nuclear materials and the metrology tries to calibrate and standardize these materials to improve the activity determination techniques applied in different fuel-cycle scopes. The essential characteristics of the safeguarded materials are low gamma energies (less than 100 keV) and emission probabilities but with high uncertainties. In this way, the metrology can contribute to homeland security defense against illicit nuclear trafficking with the identification and quantification of the safeguarded radionuclides such as uranium and thorium, using specific gamma window energy and high resolution planar or coaxial germanium detector. The efficiency curve is obtained from the reference source spectrum considering the photopeak areas corresponding the standard activities. This curve depends on radiation energy, sample geometry, photon attenuation (sample absorption and material absorption between sample-detector), dead time and sample-detector position. The metrological activity determinations of 238 U solid sources, and of 230 Th, in solution (5 ml flask), were performed using

  1. Artificial neural networks application for analysis of gamma ray spectrum obtained from the scintillation detectors

    International Nuclear Information System (INIS)

    Stegowski, Z.

    2002-01-01

    Scintillation detectors are commonly used for the gamma ray detection. Actually the small peak resolution and the significant Compton effect fraction limit their utilization in the gamma ray spectrometry analysis. This article presents the artificial neural networks (ANN) application to the analysis of the gamma ray spectra acquired from scintillation detectors. The obtained results validate the effectiveness of the ANN method to spectrometry analysis. (author)

  2. In-situ measurements in Vesivehmaa air field - STUK team

    Energy Technology Data Exchange (ETDEWEB)

    Markkanen, M.; Honkamaa, T.; Niskala, P. [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)

    1997-12-31

    Nineteen in-situ gamma-ray spectrometric measurements were performed in Vesivehmaa air field on 17th August 1995. The results for {sup 137}Cs and natural radionuclides are in good agreement with the results from soil sampling and laboratory analyses. (au).

  3. In-situ measurements in Vesivehmaa air field - STUK team

    Energy Technology Data Exchange (ETDEWEB)

    Markkanen, M; Honkamaa, T; Niskala, P [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)

    1998-12-31

    Nineteen in-situ gamma-ray spectrometric measurements were performed in Vesivehmaa air field on 17th August 1995. The results for {sup 137}Cs and natural radionuclides are in good agreement with the results from soil sampling and laboratory analyses. (au).

  4. Determination of protein content in seeds by prompt gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Carbonari, A.W.; Pecequilo, B.R.S.

    1984-01-01

    The protein level in seeds can be directly calculated through the determination of the nitrogen content in grains. The authors show here that the radioactive thermal neutron capture prompt gamma-rays technique can be used to determine the nitrogen content in grains without chemical destruction, with good precision and relative rapidity, by detecting the prompt gamma rays emitted by the 14 N(n,γ) 15 N reaction product. The samples were irradiated in the tangential tube of the IEA-R1 research reactor, in Sao Paulo, and a pair spectrometer was used for the detection of the prompt gamma-rays. The nitrogen content was determined in several samples of soybean, common bean, peas and rice and the results compared with typical nitrogen content values for each grain. 33 references, 1 figure, 1 table

  5. Study of radionuclide and element characterization of Angola marine sediment using low background gamma spectrometry and instrumental neutron activation analysis techniques

    International Nuclear Information System (INIS)

    Teixeira, M.C.P.; Vuong Huu Tan; Truong Y; Ho Manh Dung; Le Nhu Sieu; Cao Dong Vu; Nguyen Thanh Binh

    2007-01-01

    The concentrations of radionuclides and chemical elements in Angola marine sediment samples were determined by using low background gamma (LBG) spectrometry and instrumental neutron activation analysis (INAA). The combination of radionuclide and elemental concentration values yielded synergy in the validation of analytical data and identification of sediment sources modeled by multivariate factor analysis. Varimax rotation factor analysis based on the elemental concentrations revealed five sources contributed to the sediment composition, i.e. crustal, sea-salt, industrial, coal-related and Se-related sources. (author)

  6. Determination of gamma-aminobutyric acid in food matrices by isotope dilution hydrophilic interaction chromatography coupled to mass spectrometry.

    Science.gov (United States)

    Zazzeroni, Raniero; Homan, Andrew; Thain, Emma

    2009-08-01

    The estimation of the dietary intake of gamma-aminobutyric acid (GABA) is dependent upon the knowledge of its concentration values in food matrices. To this end, an isotope dilution liquid chromatography-mass spectrometry method has been developed employing the hydrophilic interaction chromatography technique for analyte separation. This approach enabled accurate quantification of GABA in apple, potato, soybeans, and orange juice without the need of a pre- or post-column derivatization reaction. A selective and precise analytical measurement has been obtained with a triple quadrupole mass spectrometer operating in multiple reaction monitoring using the method of standard additions and GABA-d(6) as an internal standard. The concentrations of GABA found in the matrices tested are 7 microg/g of apple, 342 microg/g of potatoes, 211 microg/g of soybeans, and 344 microg/mL of orange juice.

  7. An optimum analysis sequence for environmental gamma-ray spectrometry

    International Nuclear Information System (INIS)

    De la Torre, F.; Rios M, C.; Ruvalcaba A, M. G.; Mireles G, F.; Saucedo A, S.; Davila R, I.; Pinedo, J. L.

    2010-10-01

    This work aims to obtain an optimum analysis sequence for environmental gamma-ray spectroscopy by means of Genie 2000 (Canberra). Twenty different analysis sequences were customized using different peak area percentages and different algorithms for: 1) peak finding, and 2) peak area determination, and with or without the use of a library -based on evaluated nuclear data- of common gamma-ray emitters in environmental samples. The use of an optimum analysis sequence with certified nuclear information avoids the problems originated by the significant variations in out-of-date nuclear parameters of commercial software libraries. Interference-free gamma ray energies with absolute emission probabilities greater than 3.75% were included in the customized library. The gamma-ray spectroscopy system (based on a Ge Re-3522 Canberra detector) was calibrated both in energy and shape by means of the IAEA-2002 reference spectra for software intercomparison. To test the performance of the analysis sequences, the IAEA-2002 reference spectrum was used. The z-score and the reduced χ 2 criteria were used to determine the optimum analysis sequence. The results show an appreciable variation in the peak area determinations and their corresponding uncertainties. Particularly, the combination of second derivative peak locate with simple peak area integration algorithms provides the greater accuracy. Lower accuracy comes from the combination of library directed peak locate algorithm and Genie's Gamma-M peak area determination. (Author)

  8. A broadband gamma-ray spectrometry using novel unfolding algorithms for characterization of laser wakefield-generated betatron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Jong Ho, E-mail: jhjeon07@ibs.re.kr; Nakajima, Kazuhisa, E-mail: naka115@dia-net.ne.jp; Pathak, Vishwa Bandhu; Cho, Myung Hoon; Yoo, Byung Ju; Shin, Kang Woo [Center for Relativistic Laser Science, Institute for Basic Science (IBS), Gwangju 500-712 (Korea, Republic of); Kim, Hyung Taek; Sung, Jae Hee; Lee, Seung Ku; Choi, Il Woo [Center for Relativistic Laser Science, Institute for Basic Science (IBS), Gwangju 500-712 (Korea, Republic of); Advanced Photonics Research Institute, GIST, Gwangju 500-712 (Korea, Republic of); Rhee, Yong Joo [Nuclear Data Center, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Shin, Jung Hun; Jo, Sung Ha [Advanced Photonics Research Institute, GIST, Gwangju 500-712 (Korea, Republic of); Hojbota, Calin; Cho, Byeoung Ick; Nam, Chang Hee [Center for Relativistic Laser Science, Institute for Basic Science (IBS), Gwangju 500-712 (Korea, Republic of); Department of Physics and Photon Science, GIST, Gwangju 500-712 (Korea, Republic of)

    2015-12-15

    We present a high-flux, broadband gamma-ray spectrometry capable of characterizing the betatron radiation spectrum over the photon energy range from 10 keV to 20 MeV with respect to the peak photon energy, spectral bandwidth, and unique discrimination from background radiations, using a differential filtering spectrometer and the unfolding procedure based on the Monte Carlo code GEANT4. These properties are experimentally verified by measuring betatron radiation from a cm-scale laser wakefield accelerator (LWFA) driven by a 1-PW laser, using a differential filtering spectrometer consisting of a 15-filter and image plate stack. The gamma-ray spectra were derived by unfolding the photostimulated luminescence (PSL) values recorded on the image plates, using the spectrometer response matrix modeled with the Monte Carlo code GEANT4. The accuracy of unfolded betatron radiation spectra was assessed by unfolding the test PSL data simulated with GEANT4, showing an ambiguity of less than 20% and clear discrimination from the background radiation with less than 10%. The spectral analysis of betatron radiation from laser wakefield-accelerated electron beams with energies up to 3 GeV revealed radiation spectra characterized by synchrotron radiation with the critical photon energy up to 7 MeV. The gamma-ray spectrometer and unfolding method presented here facilitate an in-depth understanding of betatron radiation from LWFA process and a novel radiation source of high-quality photon beams in the MeV regime.

  9. Polymerization in situ by means of radiation gamma for the production of conducting polymeric composites

    International Nuclear Information System (INIS)

    Poblete Pulgar, Victor; Pilleux Cepeda, Mauricio; Fuenzalida Escobar, Victor; Alvarez Vargas, Mariela

    2002-01-01

    The nanocomposites synthesis of copper-methyl metacritate is made using copper spheres from 80 to 120 diameter nm, suspended in a methyl metacrilato (MMA) matrix, for different concentrations (5% to 30% of copper-v/v). The polymerization is carried out by means of gamma radiation, with 16 kGy dose applied 'in situ'. A high homogenous samples were obtained. The morphology and formation of the composite was studied by means of scanning electronic microscopy (SEM). The observed electric resistance is analyzed in function of the distance among electric contacts, meeting a strong dependence of the resistance with the homogeneous distribution of the metal in the composite. The obtained specific resistivities, in function of the concentration of the conductive metal, they are in the order of 42 Ωm for 10% v/v, being this critical concentration, the percolation threshold of the system. The obtained results show a material that is able to conserve principally the mechanical properties of the polymer and the electric properties of the conductive metal (author)

  10. Application of airborne gamma-ray spectrometry in soil/regolith mapping and applied geomorphology

    International Nuclear Information System (INIS)

    Wilford, J.R.; Bierwirth, P.N.; Craig, M.A.

    1997-01-01

    Gamma-ray spectrometric surveys are an important source of information for soil, regolith and geomorphological studies, as demonstrated by the interpretation of airborne surveys in Western Australia, central New South Wales and north Queensland. Gamma-rays emitted from the ground surface relate to the primary mineralogy and geochemistry of the bedrock, and the secondary weathered materials. Weathering modifies the distribution and concentration of radioelements from the original bedrock source. Once the radioelement response of bedrock and weathered materials is understood, the gamma-ray data can provide information on geomorphic processes and soil/regolith properties, including their mineralogy, texture, chemistry and style of weathering. This information can contribute significantly to an understanding of the weathering and geomorphic history of a region and, therefore, has the potential to be used in developing more effective land-management strategies and refining geochemical models in support of mineral exploration. Gamma-ray imagery is enhanced when combined with Landsat TM bands and digital elevation models (DEM). This synergy enables geochemical information derived from the gamma-ray data to be interpreted within a geomorphic framework. Draping gamma-ray images over DEMs as 3D landscape perspective views aids interpretation and allows the interpreter to visualise complex relationships between the gamma-ray response and landform features. 44 refs.,1 tab., 11 figs

  11. Airborne Gamma-Ray Survey in Latvia 1995/96

    DEFF Research Database (Denmark)

    Bargholz, Kim

    1998-01-01

    Based on Airborne Gamma-Ray Spectrometry measurements performed with the Danish AGS equipment in 1995 and 1996 maps of the natural radioactivity have been produdced for selected areas in Latvia. The calibration of the quipment have been improved by comparisons with soil sample measurements....

  12. In-situ pre-concentration through repeated sampling and pyrolysis for ultrasensitive determination of thallium in drinking water by electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Liu, Liwei; Zheng, Huaili; Xu, Bincheng; Xiao, Lang; Chigan, Yong; Zhangluo, Yilan

    2018-03-01

    In this paper, a procedure for in-situ pre-concentration in graphite furnace by repeated sampling and pyrolysis is proposed for the determination of ultra-trace thallium in drinking water by graphite furnace atomic absorption spectrometry (GF-AAS). Without any other laborious enrichment processes that routinely result in analyte loss and contamination, thallium was directly concentrated in the graphite furnace automatically and subsequently subject to analysis. The effects of several key factors, such as the temperature for pyrolysis and atomization, the chemical modifier, and the repeated sampling times were investigated. Under the optimized conditions, a limit of detection of 0.01µgL -1 was obtained, which fulfilled thallium determination in drinking water by GB 5749-2006 regulated by China. Successful analysis of thallium in certified water samples and drinking water samples was demonstrated, with analytical results in good agreement with the certified values and those by inductively coupled plasma mass spectrometry (ICP-MS), respectively. Routine spike-recovery tests with randomly selected drinking water samples showed satisfactory results of 80-96%. The proposed method is simple and sensitive for screening of ultra-trace thallium in drinking water samples. Copyright © 2017. Published by Elsevier B.V.

  13. Determination of tributyltin in environmental water matrices using stir bar sorptive extraction with in-situ derivatisation and large volume injection-gas chromatography-mass spectrometry.

    Science.gov (United States)

    Neng, N R; Santalla, R P; Nogueira, J M F

    2014-08-01

    Stir bar sorptive extraction with in-situ derivatization using sodium tetrahydridoborate (NaBH4) followed by liquid desorption and large volume injection-gas chromatography-mass spectrometry detection under the selected ion monitoring mode (SBSE(NaBH4)in-situ-LD/LVI-GC-MS(SIM)) was successfully developed for the determination of tributyltin (TBT) in environmental water matrices. NaBH4 proved to be an effective and easy in-situ speciation agent for TBT in aqueous media, allowing the formation of adducts with enough stability and suitable polarity for SBSE analysis. Assays performed on water samples spiked at the 10.0μg/L, yielded convenient recoveries (68.2±3.0%), showed good accuracy, suitable precision (RSD<9.0%), low detection limits (23ng/L) and excellent linear dynamic range (r(2)=0.9999) from 0.1 to 170.0µg/L, under optimized experimental conditions. By using the standard addition method, the application of the present methodology to real surface water samples allowed very good performance at the trace level. The proposed methodology proved to be a feasible alternative for routine quality control analysis, easy to implement, reliable and sensitive to monitor TBT in environmental water matrices. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. ICIT contribution to JET gamma-ray diagnostics enhancement

    International Nuclear Information System (INIS)

    Soare, S.; Curuia, M.; Zoita, V.

    2010-01-01

    Full text: Gamma-ray emission of tokamak plasmas is the result of the interaction of fast ions (fusion reaction products, including alpha particles, NBI ions, ICRH-accelerated ions) with main plasma impurities (e.g., carbon, beryllium). Gamma-ray diagnostics involve both gamma-ray imaging (cameras) and gamma-ray spectrometry (spectrometers). For the JET tokamak, gamma-ray diagnostics have been used to provide information on the characteristics of the fast ion population in plasmas. Two gamma-ray diagnostics enhancements project have been launched by JET and the MEdC/EURATOM Association has agreed to lead both of them with ICIT as projects leader. (authors)

  15. Evaluation of an automated assay system to measure soil radionuclides by L x-ray and gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Nyhan, J.W.; Drennon, B.J.; Crowell, J.M.

    1982-08-01

    An automated radionuclide assay system for conducting soil radioassays using L x-ray and gamma-ray spectrometry was evaluated. Wet chemistry assay procedures were shown to be considerably more time consuming than similar analyses of soil on this radionuclide assay system. The detection limits of 241 Am and plutonium were determined, as well as the reproducibility of radionuclide assay results. The L x-ray spectrometric measurements were compared with radiochemical analyses on several tuff samples. The assay system's intrinsic germanium detector was found to respond linearly to varying low concentrations of 241 Am and plutonium, both of which were easily detected in the presence of elevated concentrations of 137 Cs

  16. Determination and quantification of impurities found in samples of {sup 124}I using gamma spectrometry; Determinacao e quantificacao de impurezas encontradas em amostra de {sup 124}I usando a espectrometria gama

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Ronaldo Lins da; Delgado, Jose Ubiratan; Araujo, Miriam Taina Ferreira de; Laranjeira, Adilson da Silva; Poledna, Roberto; Veras, Eduardo de; Almeida, Maria Candida M. [Instituto de Radioprotecao e Dosimetria, (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Braghirolli, Ana Maria S. [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2014-07-01

    {sup 124}I, positron emitter is produced in the IEN/CNEN-RJ and used in diagnosis image of tumors. In this radioisotope production process impurities appear and health agency requires that the level of these characteristics is quantified. These radionuclides emit gamma and X-radiation, allowing the identification and quantitation by gamma spectrometry. With the use of HPGE detector, coupled with the efficiency curve, was identified {sup 125}I and {sup 126}I. The impurity levels measured in the sample were in the range of 0.5% to 90%, respectively, indicating the feasibility of the method for controlling the quality of the radiopharmaceutical.

  17. An optimum analysis sequence for environmental gamma-ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    De la Torre, F.; Rios M, C.; Ruvalcaba A, M. G.; Mireles G, F.; Saucedo A, S.; Davila R, I.; Pinedo, J. L., E-mail: fta777@hotmail.co [Universidad Autonoma de Zacatecas, Centro Regional de Estudis Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2010-10-15

    This work aims to obtain an optimum analysis sequence for environmental gamma-ray spectroscopy by means of Genie 2000 (Canberra). Twenty different analysis sequences were customized using different peak area percentages and different algorithms for: 1) peak finding, and 2) peak area determination, and with or without the use of a library -based on evaluated nuclear data- of common gamma-ray emitters in environmental samples. The use of an optimum analysis sequence with certified nuclear information avoids the problems originated by the significant variations in out-of-date nuclear parameters of commercial software libraries. Interference-free gamma ray energies with absolute emission probabilities greater than 3.75% were included in the customized library. The gamma-ray spectroscopy system (based on a Ge Re-3522 Canberra detector) was calibrated both in energy and shape by means of the IAEA-2002 reference spectra for software intercomparison. To test the performance of the analysis sequences, the IAEA-2002 reference spectrum was used. The z-score and the reduced {chi}{sup 2} criteria were used to determine the optimum analysis sequence. The results show an appreciable variation in the peak area determinations and their corresponding uncertainties. Particularly, the combination of second derivative peak locate with simple peak area integration algorithms provides the greater accuracy. Lower accuracy comes from the combination of library directed peak locate algorithm and Genie's Gamma-M peak area determination. (Author)

  18. Spectrometry techniques for radioactivity measurements

    International Nuclear Information System (INIS)

    Anilkumar, S.

    2016-01-01

    The energy of the radiation emission following the nuclear decay is unique and the characteristic of the radio nuclide which undergoes decay. Thus measurement of the energy of the radiation offers a method of identifying the radio nuclides. The prime requirement of the energy measurement is a suitable detector which shows response proportional to the energy of the radiation rather than the presence of the radiation. The response from such detectors are suitably processed and distributed with respect to the signal strength which is proportional to incident energy. This distribution is normally referred as energy spectrum and is recorded in the multichannel analyser. The measurement of energy and intensity of radiation from the spectrum is called radiation spectrometry. Thus the radiation spectrometry allows the identification and quantification of radioactive isotopes in variety of matrices. The radiation spectrometry has now become a popular radioanalytical technique in wide area of nuclear fuel cycle programs. The popular spectrometry techniques commonly used for the radioactivity measurement and analysis are Alpha spectrometry, Gamma ray spectrometry and Beta spectrometry

  19. Fourier transformation methods in the field of gamma spectrometry

    Indian Academy of Sciences (India)

    The basic principles of a new version of Fourier transformation is presented. This new version was applied to solve some main problems such as smoothing, and denoising in gamma spectroscopy. The mathematical procedures were first tested by simulated data and then by actual experimental data.

  20. Radioactivity measurements in soils surrounding four coal-fired power plants in Serbia by gamma-ray spectrometry and estimated dose

    Directory of Open Access Journals (Sweden)

    Vukašinović Ivana Ž.

    2014-01-01

    Full Text Available The study of spatial distribution of activity concentration of 238U, 226Ra, 210Pb, 232Th, 40K, and 137Cs radionuclides in the surface soil samples (n = 42 collected in the vicinity of four coal-fired power plants in Serbia is presented. Radioactivity measurements in soils performed by gamma-ray spectrometry showed values [Bqkg-1] in the range: 15-117 for 238U, 21-115 for 226Ra, 33-65 for 210Pb, 20-69 for 232Th, 324-736 for 40K, and 2-59 for 137Cs. Surface soil radio-activity that could have resulted from deposition of radionuclides from airborne discharges or resuspension of ash from disposal sites showed no enhanced levels. It was found that variation of soil textural properties, pH values, and carbonate content influenced activity levels of natural radionuclides while radiocesium activities were associated with soil organic matter content. Modification of some soil properties was observed in the immediate vicinity (<1 km of power plants where the soil was more alkaline with coarser particles (0.2-0.05 mm and carbonates accumulated. Calculated average values of the absorbed gamma dose rate and annual external effective dose originating from the terrestrial radionuclides were 69.4 nGy/h and 0.085 mSv, respectively. [Projekat Ministarstva nauke Republike Srbije, br. 4007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation

  1. On background radiation gradients – the use of airborne surveys when searching for orphan sources using mobile gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Kock, Peder; Rääf, Christopher; Samuelsson, Christer

    2014-01-01

    Systematic background radiation variations can lead to both false positives and failures to detect an orphan source when searching using car-borne mobile gamma-ray spectrometry. The stochastic variation at each point is well described by Poisson statistics, but when moving in a background radiation gradient the mean count rate will continually change, leading to inaccurate background estimations. Airborne gamma spectrometry (AGS) surveys conducted on the national level, usually in connection to mineral exploration, exist in many countries. These data hold information about the background radiation gradients which could be used at the ground level. This article describes a method that aims to incorporate the systematic as well as stochastic variations of the background radiation. We introduce a weighted moving average where the weights are calculated from existing AGS data, supplied by the Geological Survey of Sweden. To test the method we chose an area with strong background gradients, especially in the thorium component. Within the area we identified two roads which pass through the high-variability locations. The proposed method is compared with an unweighted moving average. The results show that the weighting reduces the excess false positives in the positive background gradients without introducing an excess of failures to detect a source during passage in negative gradients. -- Highlights: • We present a simple method to account for gradients in the natural background radiation. • Gradients in the natural radiation background can be modelled at the ground level using AGS data. • The number of false positives due to background gradients can be reduced by using airborne data

  2. Development of an open source software of quantitative analysis for radionuclide determination by gamma-ray spectrometry using semiconductor detectors

    International Nuclear Information System (INIS)

    Maduar, Marcelo Francis

    2010-01-01

    Radioactivity quantification of gamma-ray emitter radionuclides in samples measured by HPGe gamma-ray spectrometry relies on the analysis of the photopeaks present in the spectra, especially on the accurate determination of their net areas. Such a task is usually performed with the aid of proprietary software tools. This work presents a methodology, algorithm descriptions and an open source application, called OpenGamma, for the peak search and analysis in order to obtain the relevant peaks parameters and radionuclides activities. The computational implementation is released entirely in open-source license for the main code and with the use of open software packages for interface design and mathematical libraries. The procedure for the peak search is performed on a three step approach. Firstly a preliminary search is done by using the second-difference method, consisting in the generation of a derived spectrum in order to find candidate peaks. In the second step, the experimental peaks widths are assessed and well formed and isolated ones are chosen to obtain a FWHM vs. channel relationship, by application of the Levenberg-Marquardt minimization method for non-linear fitting. Lastly, regions of the spectrum with grouped peaks are marked and a non-linear fit is again applied to each region to obtain baseline and photopeaks terms; from these terms, peaks net areas are then assessed. (author)

  3. Committed effective dose determination in cereal flours by gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Scheibel, Viviane

    2006-01-01

    The health impact from radionuclides ingestion of foodstuffs was evaluated by the committed effective doses determined in commercial samples of South-Brazilian cereal flours (soy, wheat, corn, manioc, rye, oat, barley and rice flour). The radioactivity traces of 228 Th, 228 Ra, 226 Ra, 40 K, 7 Be and 137 Cs were measured by gamma-ray spectrometry employing a 66% relative efficiency HPGe detector. The energy resolution for the 1332.46 keV line of 60 Co was 2.03 keV. The committed effective doses were calculated with the activities analyzed in the present flour samples, the foodstuff rates of consumption (Brazilian Institute of Geography and Statistics) and the ingestion dose coefficients (International Commission of Radiological Protection). The reliability median activities were verified with χ 2 tests, assuring the fittings quality. The highest concentration levels of 228 Th and 40 K were 3.5 ± 0.4 and 1469 ± 17 Bq.kg -1 for soy flour, respectively, with 95% of confidence level. The lower limit of detection for 137 Cs ranged from 0.04 to 0.4 Bq.kg -1 . The highest committed effective dose was 0.36 μSv.y -1 for 228 Ra in manioc flour (adults). All committed effective doses determined at the present work were lower than the UNSCEAR limits of 140 μSv.y -1 and much lower than the ICRP (1991) limits of 1 mSv.y -1 , for general public. There are few literature references for natural and artificial radionuclides in foodstuffs and mainly for committed effective doses. This work brings the barley flour data, which is not present at the literature and 7 Be data which is not encountered in foodstuffs at the literature, besides all the other flours data information about activities and committed effective doses. (author)

  4. Very little in situ produced radiocarbon retained in accumulating Antarctic ice

    International Nuclear Information System (INIS)

    Kemp, W.J.M. van der; Alderliesten, C.; Borg, K. van der; Holmlund, P.; Jong, A.F.M. de; Karloef, L.; Lamers, R.A.N.; Oerlemans, J.; Thomassen, M.; Wal, R.S.W. van de

    2000-01-01

    Ice samples from Dronning Maud Land, Antarctica, were analyzed for 14 CO 2 and 14 CO by accelerator mass spectrometry. Only a small amount (∼2%) of in situ produced radiocarbon was detected. The calibrated radiocarbon ages, corrected for in situ produced 14 C, are in fair agreement with age estimates obtained from stratigraphical methods added to a gas inclusion model. The ages of the entrapped air range from recent to ca. 1200 AD

  5. Application of Ge/Li/-spectrometry in boreholes

    International Nuclear Information System (INIS)

    Chrusciel, E.

    1976-01-01

    The paper presents the results of Ge/Li/ spectrometry applications in boreholes. The natural radioactivity measurements as well as rare elements determinations with the use of 252 Cf neutron source and capture-gamma and activation techniques are described. The minimum concentrations of certain elements to be determined in the field circumstances are evaluated on the basis of the model experiments. (author)

  6. Landscape Erosion Assessment using the {sup 137}Cs-based Method through Laboratory and in-situ Gamma Spectrometry: An Update of On-going Research and Progress

    Energy Technology Data Exchange (ETDEWEB)

    Gonsalves, B. C.; Toloza, A.; Augustin, F.; Dercon, G.; Mabit, L. [Soil and Water Management and Crop Nutrition Laboratory (SWMCNL), Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Seibersdorf (Austria); Darby, I. G.; Kaiser, R. B. [Nuclear Science and Instrumentation Laboratory (NSIL), Division of Physical and Chemical Sciences, Seibersdorf (Austria)

    2014-07-15

    The objective of this research is to compare in-situ {sup 137}Cs measurements using an on-site lanthanum bromide (LaBr{sub 3} (Ce)) scintillation detector with those from a conventional laboratory-based HPGe detector to assess soil erosion. We aimed to establish (i) the strength of the relationship between in-situ and laboratory based measurements, and (ii) to develop improved tools for landscape-based soil erosion assessments in our continuing research, reported in the January 2013 Soils Newsletter.

  7. Gamma-ray spectrometry applied to agricultural soil in the northwest of the State of Rio de Janeiro; Gamaespectrometria aplicada em solo agricola no noroeste do Estado do Rio de Janeiro

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Andrea Cristina Lima dos; Nascimento, Carlos Tadeu Carvalho do [Instituto de Geociencias, Universidade de Brasilia, DF (Brazil); Menezes, Paulo de Tarso Luiz, E-mail: andrealima@unb.br, E-mail: carlostadeu@unb.br, E-mail: ptarsomenezes@pq.cnpq.br [Faculdade de Geologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ (Brazil)

    2008-04-15

    The present work presents the use of gamma-ray spectrometry applied to precision agriculture in a sub-tropical area. Our dataset comprises measurements both in rock and residual soil. The soil dataset shows a reduction of 20% on U and Th and 10% on K, when compared to rock samples. This difference could be related to K supplementation associated to chemical fertilization. (author)

  8. Imaging Mass Spectrometry in Neuroscience

    Science.gov (United States)

    2013-01-01

    Imaging mass spectrometry is an emerging technique of great potential for investigating the chemical architecture in biological matrices. Although the potential for studying neurobiological systems is evident, the relevance of the technique for application in neuroscience is still in its infancy. In the present Review, a principal overview of the different approaches, including matrix assisted laser desorption ionization and secondary ion mass spectrometry, is provided with particular focus on their strengths and limitations for studying different neurochemical species in situ and in vitro. The potential of the various approaches is discussed based on both fundamental and biomedical neuroscience research. This Review aims to serve as a general guide to familiarize the neuroscience community and other biomedical researchers with the technique, highlighting its great potential and suitability for comprehensive and specific chemical imaging. PMID:23530951

  9. Determination of 226Ra contamination depth in soil using the multiple photopeaks method

    International Nuclear Information System (INIS)

    Haddad, Kh.; Al-Masri, M.S.; Doubal, A.W.

    2014-01-01

    Radioactive contamination presents a diverse range of challenges in many industries. Determination of radioactive contamination depth plays a vital role in the assessment of contaminated sites, because it can be used to estimate the activity content. It is determined traditionally by measuring the activity distributions along the depth. This approach gives accurate results, but it is time consuming, lengthy and costly. The multiple photopeaks method was developed in this work for 226 Ra contamination depth determination in a NORM contaminated soil using in-situ gamma spectrometry. The developed method bases on linear correlation between the attenuation ratio of different gamma lines emitted by 214 Bi and the 226 Ra contamination depth. Although this method is approximate, but it is much simpler, faster and cheaper than the traditional one. This method can be applied for any case of multiple gamma emitter contaminant. -- Highlights: • The multiple photopeaks method was developed for 226 Ra contamination depth determination using in-situ gamma spectrometry. • The method bases on linear correlation between the attenuation ratio of 214 Bi gamma lines and 226 Ra contamination depth. • This method is simpler, faster and cheaper than the traditional one, it can be applied for any multiple gamma contaminant

  10. The application of geophysical logging at in-situ leaching uranium mine in China

    International Nuclear Information System (INIS)

    Liu Zeyao; Xu Shusheng; Li Zhongqiu

    1999-01-01

    The status of work, instrument and method employed for geophysical logging in different stages at in-situ leaching uranium mine are discussed and the development of software, electrical current logging and gamma ray logging are presented based on the requirement of in-situ leaching of uranium. In addition, new function and method with regard to home instrument are proposed for future work

  11. Mass Spectrometry in the Home and Garden

    Science.gov (United States)

    Pulliam, Christopher J.; Bain, Ryan M.; Wiley, Joshua S.; Ouyang, Zheng; Cooks, R. Graham

    2015-02-01

    Identification of active components in a variety of chemical products used directly by consumers is described at both trace and bulk levels using mass spectrometry. The combination of external ambient ionization with a portable mass spectrometer capable of tandem mass spectrometry provides high chemical specificity and sensitivity as well as allowing on-site monitoring. These experiments were done using a custom-built portable ion trap mass spectrometer in combination with the ambient ionization methods of paper spray, leaf spray, and low temperature plasma ionization. Bactericides, garden chemicals, air fresheners, and other products were examined. Herbicide applied to suburban lawns was detected in situ on single leaves 5 d after application.

  12. Study pf apatite accurrence from Gaviao and Serra de Jacabina gold deposit by scintillometry and gamma spectrometry

    International Nuclear Information System (INIS)

    Barreto, P.T.

    1974-01-01

    This work presents the results of radiogeologic reconnaissance in the Cenozoic, Mesozoic and Pre-Cambrian formations, localized between Salvador and Miguel Calmon, and of the radiogeologic detail study from areas of the radioactive anomalies: Gaviao in the Riacho do Lacuipe and Canavieira Mine, in the Jacobina, Bahia States Scintilometry and gamma spectrometry results make possible to conclude by the association, in the Gaviao's apatite mineralization with throrium and the gold of the Serra de Corrego's conglamerate with uranium, make possible in the both case, orient the Search and the mining by scintilometry. The petrographic study and the radiactivity elements dispersion, suggest a sedimentary primary origin to the regional metamorphic rocks. In the Canavieiras mine was evident the stratigraphic control of the gold, associated to uranium and pirite in the conglomerates. (C.D.G.) [pt

  13. Natural and artificial nuclides in Salesópolis reservoir by gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Paulo S.C.; Semmler, Renato; Zahn, Guilherme S.; Rocha, Flávio R.; Damatto, Sandra R.; Fávaro, Déborah I.T., E-mail: pscsilva@ipen.br, E-mail: rsemmler@ipen.br, E-mail: gzahn@ipen.br, E-mail: flavio@baquara.com, E-mail: damatto@ipen.br, E-mail: defavaro@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    Natural radioactivity is ubiquitous in the environment mainly due to the presence of the nuclides from the uranium and thorium series and {sup 40}K. Although in the South Hemisphere nuclear tests have been fewer in number than that in the North, artificial radionuclides can also be found spread at ground level. In this study, the activity concentrations of natural nuclides from the uranium and thorium series, {sup 40}K and the artificial {sup 137}Cs were determined in a sediment core with 42 cm depth collected in the middle of the Salesópolis reservoir, located in the Metropolitan Region of São Paulo city (SPMR). The Usina Parque Rio Tietê reservoir belongs to the Alto do Tietê system for the capture, storage and treatment of water for SPMR. Therefore, the quality of the water and sediments of this dam is of great importance. The activity concentrations were measured by gamma spectrometry. Samples were measured and saved at regular intervals at a maximum of 160 000 seconds. The gross area were determined for each peak and plotted against time and the counting rate was obtained by the slope of the curve. Background and reference materials were also counted and treated in the same way. Results showed that {sup 226}Ra varied from 45 to 116 Bq kg{sup -1}; {sup 228}Ra, from 80 to 165 Bq kg{sup -1}; {sup 40}K, from 155 to 1 187 Bq kg{sup -1} and {sup 137}Cs varied from 0.3 to 7 Bq kg{sup -1}. The methodology applied for determining low levels of {sup 137}Cs in sediment proved to be efficient and reproducible. (author)

  14. Natural and artificial nuclides in Salesópolis reservoir by gamma spectrometry

    International Nuclear Information System (INIS)

    Silva, Paulo S.C.; Semmler, Renato; Zahn, Guilherme S.; Rocha, Flávio R.; Damatto, Sandra R.; Fávaro, Déborah I.T.

    2017-01-01

    Natural radioactivity is ubiquitous in the environment mainly due to the presence of the nuclides from the uranium and thorium series and 40 K. Although in the South Hemisphere nuclear tests have been fewer in number than that in the North, artificial radionuclides can also be found spread at ground level. In this study, the activity concentrations of natural nuclides from the uranium and thorium series, 40 K and the artificial 137 Cs were determined in a sediment core with 42 cm depth collected in the middle of the Salesópolis reservoir, located in the Metropolitan Region of São Paulo city (SPMR). The Usina Parque Rio Tietê reservoir belongs to the Alto do Tietê system for the capture, storage and treatment of water for SPMR. Therefore, the quality of the water and sediments of this dam is of great importance. The activity concentrations were measured by gamma spectrometry. Samples were measured and saved at regular intervals at a maximum of 160 000 seconds. The gross area were determined for each peak and plotted against time and the counting rate was obtained by the slope of the curve. Background and reference materials were also counted and treated in the same way. Results showed that 226 Ra varied from 45 to 116 Bq kg -1 ; 228 Ra, from 80 to 165 Bq kg -1 ; 40 K, from 155 to 1 187 Bq kg -1 and 137 Cs varied from 0.3 to 7 Bq kg -1 . The methodology applied for determining low levels of 137 Cs in sediment proved to be efficient and reproducible. (author)

  15. 134Cs emission probabilities determination by gamma spectrometry

    Science.gov (United States)

    de Almeida, M. C. M.; Poledna, R.; Delgado, J. U.; Silva, R. L.; Araujo, M. T. F.; da Silva, C. J.

    2018-03-01

    The National Laboratory for Ionizing Radiation Metrology (LNMRI/IRD/CNEN) of Rio de Janeiro performed primary and secondary standardization of different radionuclides reaching satisfactory uncertainties. A solution of 134Cs radionuclide was purchased from commercial supplier to emission probabilities determination of some of its energies. 134Cs is a beta gamma emitter with 754 days of half-life. This radionuclide is used as standard in environmental, water and food control. It is also important to germanium detector calibration. The gamma emission probabilities (Pγ) were determined mainly for some energies of the 134Cs by efficiency curve method and the Pγ absolute uncertainties obtained were below 1% (k=1).

  16. Estimation of americium in cemented waste block using gamma ray spectrometry

    International Nuclear Information System (INIS)

    Singh, Sarbjit; Mhatre, Amol; Sagar, Veena

    2012-05-01

    A method was developed for the estimation of 241 Am present in the cemented waste block which was cylindrical in shape. In such large sample, the attenuation of gamma rays increases with size of the sample and density of the material present. Attenuation correction was incorporated using linear attenuation coefficients of 59.54 keV gamma ray of 241 Am. Also in such large samples, error due to the distribution of activity is more. Estimation of 241 Am in the cemented sample was carried out by applying corrections for attenuation and for the sample geometry. (author)

  17. Gamma spectrometry of EFTTRA T2BIS R280.2. Gamma scan wires 6 through 10

    International Nuclear Information System (INIS)

    Dassel, G.; Buurveld, H.A.; Plakman, J.C.

    1996-11-01

    In the frame work of the EFTTRA programme on recycling of actinides and fission products, five gamma scan wires which were included in the experiment R280.2 T2bis have been examined by gamma scanning. The results of the measurements have been described in this report. (orig.)

  18. The metrological activity determination of {sup 238} U and {sup 230} Th by gamma spectrometry to industrial fuel-cycle application

    Energy Technology Data Exchange (ETDEWEB)

    Almeida M, M.C. de; Delgado, J.U.; Poledna, R. [Instituto de Radioprotecao e Dosimetria- IRD/SEMRA, CNEN, Av. Salvador Allende s/n, Recreio, CEP 22780-160, Rio de Janeiro (Brazil)]. e-mail: marcandida@yahoo.com.br

    2006-07-01

    This work describes the difficulty for determining the activity of {sup 238} U and {sup 230} Th using gamma spectrometry due to the low gamma-ray emission probabilities of 92 and 67 keV, and, mainly, the associated high uncertainties about 13 and 11%, respectively. {sup 230} Th is a {sup 238} U daughter and it is product from uranium mills and refineries. {sup 230} Th decays to {sup 226} Ra and this decay has to be measured because these radionuclides are not in secular equilibrium with their daughter products, besides the gamma-energies have high uncertainties in the emission probabilities. These radionuclides, mostly {sup 238} U, are important in the nuclear fuel-cycle, since the mining of uranium ore, where the nominal isotopic content of natural uranium is 99.27% of {sup 238} U, until the irradiated fuel reprocessing, where this isotope, a fertile material, is recovered to be used again. The uranium and thorium are considered safeguarded nuclear materials and the metrology tries to calibrate and standardize these materials to improve the activity determination techniques applied in different fuel-cycle scopes. The essential characteristics of the safeguarded materials are low gamma energies (less than 100 keV) and emission probabilities but with high uncertainties. In this way, the metrology can contribute to homeland security defense against illicit nuclear trafficking with the identification and quantification of the safeguarded radionuclides such as uranium and thorium, using specific gamma window energy and high resolution planar or coaxial germanium detector. The efficiency curve is obtained from the reference source spectrum considering the photopeak areas corresponding the standard activities. This curve depends on radiation energy, sample geometry, photon attenuation (sample absorption and material absorption between sample-detector), dead time and sample-detector position. The metrological activity determinations of {sup 238} U solid sources, and of

  19. Drill-Core Scanning for Radioelements by Gamma-Ray Spectrometry

    DEFF Research Database (Denmark)

    Løvborg, Leif; Wollenberg, H.; Rose-Hansen, J.

    1972-01-01

    A system has been developed for the continuous and stepwise scanning of rock drill cores for gamma-ray spectrometric determinations of uranium, thorium, and potassium. The apparatus accomodates 3- to 4-cm-diameter core as it passes two opposing 2-inch diameter by 3-inch- thick NaI(Tl) detectors, ......, disclosing detailed variations of U and Th. Contents of U and Th determined by scanning of drill core were consistent with the gross gamma-ray counting rates measured in the boreholes. ©1972 Society of Exploration Geophysicists......A system has been developed for the continuous and stepwise scanning of rock drill cores for gamma-ray spectrometric determinations of uranium, thorium, and potassium. The apparatus accomodates 3- to 4-cm-diameter core as it passes two opposing 2-inch diameter by 3-inch- thick NaI(Tl) detectors...

  20. Imaging mass spectrometry tackles interfacial challenges in electrochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Xiao-Ying

    2017-12-01

    Electrochemistry has played a significant role in many research fields. Owing to its sensitivity and selectivity, in situ electroanalysis has been widely used as a fast and economical means for achieving outstanding results. Although many spectroscopic techniques have been used in electrochemistry, the challenges to capture short-lived intermediate species as a result of electron transfer in the buried solid electrode and electrolyte solution interface remains a grand challenge. In situ imaging mass spectrometry (IMS) recently has been extended to capture transient species in electrochemistry. This review intends to summarize newest development of IMS and its applications in advancing fundamental electrochemistry.