Science.gov

Sample records for aerial gamma spectrometry

  1. Modern aerial gamma-ray spectrometry and regional potassium map of the conterminous United States

    USGS Publications Warehouse

    Duval, Joseph S.

    1990-01-01

    The aerial gamma-ray data were obtained as part of the National Uranium Resource Evaluation (NURE) Program sponsored by the U.S. Department of Energy during the period 1975-1983. References for the Open-File Reports that describe the surveys and data collection can be found in Bendix Field Engineering Corp. (1983). The aerial surveys were flown by contractors using fixed-wing and helicopter systems with 33-50 L (liters) of thallium-activated sodium iodide (NaI (TI)) crystals. The nominal survey altitude used is 122 m. The survey lines were generally east-west with line spacings of 1.6-10 km. Tie lines were flown perpendicular to the flight lines at intervals of 16- 30 km. The data were corrected for background from aircraft contamination and cosmic rays, altitude variations, airborne 214Bi, and Compton scattering. The gamma-ray systems were calibrated using the calibrations pads at Grand Junction, Colorado (Ward, 1978 ) and the dynamic test strip at Lake Mead, Arizona (Geodata International, Inc., 1977).  

  2. Low-level gamma-ray spectrometry

    SciTech Connect

    Brodzinski, R.L.

    1990-10-01

    Low-level gamma-ray spectrometry generally equates to high-sensitivity gamma-ray spectrometry that can be attained by background reduction, selective signal identification, or some combination of both. Various methods for selectively identifying gamma-ray events and for reducing the background in gamma-ray spectrometers are given. The relative magnitude of each effect on overall sensitivity and the relative cost'' for implementing them are given so that a cost/benefit comparison can be made and a sufficiently sensitive spectrometer system can be designed for any application without going to excessive or unnecessary expense. 10 refs., 8 figs.

  3. Airborne Gamma-Spectrometry in Switzerland

    NASA Astrophysics Data System (ADS)

    Butterweck, Gernot; Bucher, Benno; Rybach, Ladislaus

    2008-08-01

    Airborne gamma-spectrometry is able to obtain fast radiological information over large areas. The airborne gamma-spectrometry unit deployed in Switzerland by the Swiss National Emergency Operations Centre (NEOC) consists of a Swiss army Super Puma helicopter equipped with four NaI-Detectors with a total volume of 17 liters, associated electronics and a real-time data evaluation and mapping unit developed by the Swiss Federal Institute of Technology (ETH) and the Paul Scherrer Institut (PSI). The operational readiness of the airborne gamma-spectrometry system is validated in annual exercises of one week duration. Data from 2005 and 2006 exercises are represented in maps of 137Cs activity concentration for two towns located in southern and western Switzerland. An indicator of man-made radioactivity (MMGC ratio) is demonstrated for an area with four different types of nuclear installations. The intercomparison between airborne gamma-spectrometry and ground measurements showed good agreement between both methods.

  4. Airborne Gamma-Spectrometry in Switzerland

    SciTech Connect

    Butterweck, Gernot; Bucher, Benno; Rybach, Ladislaus

    2008-08-07

    Airborne gamma-spectrometry is able to obtain fast radiological information over large areas. The airborne gamma-spectrometry unit deployed in Switzerland by the Swiss National Emergency Operations Centre (NEOC) consists of a Swiss army Super Puma helicopter equipped with four NaI-Detectors with a total volume of 17 liters, associated electronics and a real-time data evaluation and mapping unit developed by the Swiss Federal Institute of Technology (ETH) and the Paul Scherrer Institut (PSI). The operational readiness of the airborne gamma-spectrometry system is validated in annual exercises of one week duration. Data from 2005 and 2006 exercises are represented in maps of {sup 137}Cs activity concentration for two towns located in southern and western Switzerland. An indicator of man-made radioactivity (MMGC ratio) is demonstrated for an area with four different types of nuclear installations. The intercomparison between airborne gamma-spectrometry and ground measurements showed good agreement between both methods.

  5. Environmental monitoring and in situ gamma spectrometry

    NASA Astrophysics Data System (ADS)

    Klusoň, J.

    2001-06-01

    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, spent fuel storages and waste depositories, radioactive contamination measurements and mapping, environmental, radiohygienic and radiation safety studies, geological prospecting and mapping, etc. Progressive spectrometric methods based on scintillation and semiconductor spectrometry and spectral deconvolution are discussed, including experimental arrangement as well as detection system responses/response matrixes simulation using stochastic (Monte Carlo) models. Methods for ground-level and airborne measurements are presented.

  6. GAMMA FACILITY, TRA641. AERIAL CONTEXTUAL VIEW OF GAMMA FACILITY, UNDER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GAMMA FACILITY, TRA-641. AERIAL CONTEXTUAL VIEW OF GAMMA FACILITY, UNDER CONSTRUCTION NEXT TO CONTROL HOUSE, TRA-620. CAMERA FACING NORTHWEST. CONCRETE SLAB AND BUILDING AT RIGHT EDGE OF VIEW IS TRA-614, IN USE AS A COLD METALLURGICAL LAB. INL NEGATIVE NO. 13187. Unknown Photographer, 11/24/1954 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  7. Recent advances in aerial gamma-ray surveying.

    PubMed

    Dickson, Bruce L

    2004-01-01

    Aerial gamma-ray surveying uses NaI(Tl) detectors mounted in small aircraft to measure gamma radiation, emitted from the earth's surface. The data are collected as gamma-ray spectra, typically with 1 s counting times, from which are derived K, U and Th concentrations in the ground. Applications of aerial surveying include geological mapping for mineral exploration, soil mapping for agriculture, pollution studies and location of lost sources. Recent advances in applying statistical methods to the spectral data have resulted in large reductions in the noise levels in the surveys. Some of the methods available to do this include noise adjusted singular value decomposition (NASVD) [Proceedings of Exploration 97: Fourth Decennial International Conference on Mineral Exploration (1997) 753] and maximum noise fraction (MNF) and enhanced MNF (eMNF) [Explor. Geophys. 31 (2000) 73]. These methods, in general, apply normalization for variance to the spectra, use a principal component method to obtain the "significant" components of the data and reconstruct cleaned spectra, which are then processed in a standard manner to get radionuclide concentrations. However, they differ in the detail of the application and thus give slightly different results. In this paper, the application of noise reduction methods to various synthetic surveys is used to examine the strengths and weaknesses of the methods. In tests where there are high correlations between U and Th, the eMNF method performs best although the results are improved by prior clustering of the data by the Th/U ratio. If the data show no correlations, then the effectiveness of all the noise removal methods is reduced. If a data set is small (<1500 spectra), then MNF appears to be the better method. Consideration of the various tests suggests an optimum process whereby spectra are sorted into groups by the Th/U ratio of areas identified in a standard processing and then cleaned by eMNF or MNF, depending on the number of spectra

  8. EML Gamma Spectrometry Data Evaluation Program

    SciTech Connect

    Decker, Karin M.

    2001-01-01

    This report presents the results of the analyses for the third EML Gamma Spectrometry Data Evaluation Program (October 1999). This program assists laboratories in providing more accurate gamma spectra analysis results and provides a means for users of gamma data to assess how a laboratory performed on various types of gamma spectrometry analyses. This is accomplished through the use of synthetic gamma spectra. A calibration spectrum, a background spectrum, and three sample spectra are sent to each participant in the spectral file format requested by the laboratory. The calibration spectrum contains nuclides covering the energy range from 59.5 keV to 1836 keV. The participants are told fallout and fission product nuclides could be present. The sample spectra are designed to test the ability of the software and user to properly resolve multiplets and to identify and quantify nuclides in a complicated fission product spectrum. The participants were asked to report values and uncertainties as Becquerel per sample with no decay correction. Thirty-one sets of results were reported from a total of 60 laboratories who received the spectra. Six foreign laboratories participated. The percentage of the results within 1 of the expected value was 68, 33, and 46 for samples 1, 2, and 3, respectively. From all three samples, 18% of the results were more than 3 from the expected value. Eighty-three (12%) values out of a total of 682 expected results were not reported for the three samples. Approximately 30% of these false negatives were due the laboratories not reporting 144Pr in sample 2 which was present at the minimum detectable activity level. There were 53 false positives reported with 25% of these responses due to problems with background subtraction. The results show improvement in the ability of the software or user to resolve peaks separated by 1 keV. Improvement is still needed either in the analysis report produced by the software or in the review of these

  9. Parametric Studies for 233U Gamma Spectrometry

    SciTech Connect

    Scheffing, C.C.; Krichinsky, A.

    2004-01-01

    Quantification of special nuclear material is a necessary aspect to assuring material accountability and is often accomplished using non-destructive gamma spectrometry. For 233U, gamma rays are affected by matrix and packaging attenuation and by a strong Compton continuum from decay products of 232U (inherently found in 233U) that obscure 233U gamma photopeaks. This project, based on current work at the national repository for separated 233U located at Oak Ridge National Laboratory (ORNL), explores the effects of various parameters on the quantification of 233U– including material form and geometry. Using an attenuation correction methodology for calculating the mass of 233U from NDA analysis, a bias of almost 75% less than the actual 233U mass was identified. The source of the bias needs to be understood at a more fundamental level for further use of this quantification method. Therefore, controlled experiments using well characterized packages of 233U were conducted at the repository and are presented in this paper.

  10. Composite mapping experiences in airborne gamma spectrometry.

    PubMed

    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.

  11. EML Gamma Spectrometry Data Evaluation Program

    SciTech Connect

    Decker, Karin M.

    1998-02-28

    This report represents the results of the analyses for the second EML Gamma Spectrometry Data Evaluation Program (August 1997). A calibration spectrum, a background spectrum and three sample spectra were included for each software format as part of the evaluation. The calibration spectrum contained nuclides covering the range from 59.5 keV to 1836 keV. The participants were told fallout and fission product nuclides as well as naturally occurring nuclides could be present. The samples were designed to test the detection and quantification of very low levels of nuclides and the ability of the software and user to properly resolve multiplets. The participants were asked to report values and uncertainties as Becquerel per sample with no decay correction. Twenty-nine sets of results were reported from a total of 70 laboratories who received the spectra. The percentage of the results within 1 F of the expected value was 76, 67, and 55 for samples 1, 2, and 3, respectively. From all three samples, 12% of the results were more than 3 F from the expected value. Sixty-two nuclides out of a total of 580 expected results were not reported for the three samples. Sixty percent of these false negatives were due to nuclides which were present at the minimum detectable activity level. There were 53 false positives reported with 60% of the responses due to problems with background subtraction. The results indicate that the Program is beneficial to the participating laboratories in that it provides them with analysis problems that are difficult to create with spiked samples due to the unavailability of many nuclides and the short half-lives of others. EML will continue its annual distribution, the third is to be held in March 1999.

  12. Gamma spectrometry of the minor bodies of the solar system

    SciTech Connect

    Surkov, Yu.A.; Moskaleva, L.P.; Manvelyan, O.S.

    1987-01-01

    The authors investigate the possibility of determining the elemental composition of the surfaces of minor bodies of the solar system (asteroids, the Martian satellites Phobos and Deimos, etc.) using spacecraft-based ..gamma..-spectrometry. The dependence of ..gamma..-photon flux on altitude above the body was calculated for body radii from 13 to 500 km. Estimates were made of the sensitivity of the determination of basic rock-forming elements with respect to changes in geometry of a factor of two, using ..gamma..-spectrometry with a 100 mm by 100 mm crystal of NaI(Tl). Finally, the time required to determine the stipulated characteristic ..gamma..-radiation of surface rocks with the given precision was derived as a function of altitude.

  13. A gamma-ray spectrometry analysis software environment.

    PubMed

    Lutter, G; Hult, M; Marissens, G; Stroh, H; Tzika, F

    2017-06-30

    At the JRC-Geel's RadioNuclide Metrology sector, a Monte Carlo code based on EGSnrc, and a general purpose calculation sheet implemented in Microsoft Excel(®), have been developed to make the quantitative gamma-ray spectrometry analysis of samples simpler and more robust. The further aim is that the software can be used by non-experts in gamma-ray spectrometry e.g. external researchers using JRC-Geel's facilities through the EUFRAT transnational access scheme. This paper presents the developed Monte Carlo software and the functionality included in the calculation sheet. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. National Uranium Resource Evaluation. General procedure for calibration and reduction of aerial gamma-ray measurements: specification BFEC 1250-B

    SciTech Connect

    Purvance, D.; Novak, E.

    1983-12-01

    The information contained in this specification was acquired over the course of the US Department of Energy (DOE) National Uranium Resource Evaluation (NURE) program during the period 1974 through 1982. NURE was a program of the DOE Grand Junction Area Office to acquire and compile geologic and other information with which to assess the magnitude and distribution of uranium resources and to determine areas favorable for the occurrence of uranium in the United States. Bendix Field Engineering Corporation (BFEC) has been the operating contractor for the DOE Grand Junction facility. The requirements stipulated herein had been incorporated as contractual specifications for the various subcontractors engaged in the aerial gamma-ray surveys, which were a major aspect of the NURE program. Although this phase of NURE activities has been completed, there exists valuable knowledge gained from these years of experience in the calibration of gamma-ray spectrometer systems and in the reduction of calibration data. Specification BFEC 1250-B is being open-filed by the US Department of Energy at this time to make this knowledge available to those desiring to apply gamma-ray spectrometry to other geophysical problems.

  15. Photon energy conversion efficiency in gamma-ray spectrometry.

    PubMed

    Švec, Anton

    2016-01-01

    Photon energy conversion efficiency coefficient is presented as the ratio of total energy registered in the collected spectrum to the emitted photon energy. This parameter is calculated from the conventional gamma-ray histogram and in principle is not affected by coincidence phenomena. This feature makes it particularly useful for calibration and measurement of radionuclide samples at close geometries. It complements the number of efficiency parameters used in gamma-ray spectrometry and can partly change the view as to how the gamma-ray spectra are displayed and processed.

  16. Profiles of gamma-ray and magnetic data from aerial surveys over the conterminous United States

    USGS Publications Warehouse

    Duval, Joseph S.; Riggle, Frederic E.

    1999-01-01

    This publication contains images for the conterminous U.S. generated from geophysical data, software for displaying and analyzing the images, and software for displaying and examining the profile data from the aerial surveys flown as part of the National Uranium Resource Evaluation (NURE) Program of the U.S. Department of Energy. The images included are of gamma-ray data (uranium, thorium, and potassium channels), Bouguer gravity data, isostatic residual gravity data, aeromagnetic anomalies, topography, and topography with bathymetry.

  17. New shield for gamma-ray spectrometry

    NASA Technical Reports Server (NTRS)

    Brar, S. S.; Gustafson, P. F.; Nelson, D. M.

    1969-01-01

    Gamma-ray shield that can be evacuated, refilled with a clean gas, and pressurized for exclusion of airborne radioactive contaminants effectively lowers background noise. Under working conditions, repeated evacuation and filling procedures have not adversely affected the sensitivity and resolution of the crystal detector.

  18. A dedicated LIMS for routine gamma-ray spectrometry.

    PubMed

    Bruggeman, M; Verheyen, L; Vidmar, T

    2014-05-01

    We developed a Microsoft(®) Access-based LIMS (Laboratory Information and Management Systems), γ-LIMS, for the management of our gamma-spectrometry laboratory, in which thousands of routine, but high-quality analyses are performed each year. This paper explains the main features of the γ-LIMS and puts special attention on the interfacing methods and solutions for using the Genie™2000 spectrometry software in conjunction with the EFFTRAN package, which serves for efficiency transfer calculations, coincidence summing corrections and a procedure for uncertainty estimation. © 2013 Published by Elsevier Ltd.

  19. A Case Study Correlating Innovative Gamma Ray Scanning Detection Systems Data to Surface Soil Gamma Spectrometry Results - 13580

    SciTech Connect

    Thompson, Shannon; Rodriguez, Rene; Billock, Paul; Lit, Peter

    2013-07-01

    HydroGeoLogic (HGL), Inc. completed a United States Environmental Protection Agency (USEPA) study to characterize radiological contamination at a site near Canoga Park, California. The characterized area contained 470 acres including the site of a prototype commercial nuclear reactor and other nuclear design, testing, and support operations from the 1950's until 1988 [1]. The site history included radiological releases during operation followed by D and D activities. The characterization was conducted under an accelerated schedule and the results will support the project remediation. The project has a rigorous cleanup to background agenda and does not allow for comparison to risk-based guidelines. To target soil sample locations, multiple lines of evidence were evaluated including a gamma radiation survey, geophysical surveys, historical site assessment, aerial photographs, and former worker interviews. Due to the time since production and decay, the primary gamma emitting radionuclide remaining is cesium-137 (Cs-137). The gamma ray survey covered diverse, rugged terrain using custom designed sodium iodide thallium-activated (NaI(Tl)) scintillation detection systems. The survey goals included attaining 100% ground surface coverage and detecting gamma radiation as sensitively as possible. The effectiveness of innovative gamma ray detection systems was tested by correlating field Cs-137 static count ratios to Cs-137 laboratory gamma spectrometry results. As a case study, the area encompassing the former location of the first nuclear power station in the U. S. was scanned, and second by second global positioning system (GPS)-linked gamma spectral data were evaluated by examining total count rate and nuclide-specific regions of interest. To compensate for Compton scattering from higher energy naturally occurring radionuclides (U-238, Th-232 and their progeny, and K-40), count rate ratios of anthropogenic nuclide-specific regions of interest to the total count rate were

  20. Martian Provinces From Neutron and Gamma Spectrometry

    NASA Astrophysics Data System (ADS)

    Gasnault, O.

    2003-12-01

    This study intends to identify and characterize the major provinces at the surface of Mars. We used the data from the Neutron Spectrometer (NS) and the Gamma-ray Sensor Head (GSH) aboard Mars Odyssey. NS data help to define broad provinces that should present uniform composition. GSH data can be then summed over these provinces to derive their chemical compositions with good statistics. At the present stage, we manage to conduct the first step that identifies the provinces, while the second step is still under progress to characterize them. Variations in NS epithermal and fast neutron data are largely dominated by the distribution of hydrogen and carbon at the surface or at shallow depths. Neutrons are also affected by the presence of an atmosphere. To limit these effects, we chose frost free data (i.e. measured during the summer at high-latitudes), between -60 and +60 degrees latitude, and corrected for atmospheric thickness (normalization to 16 g/cm2). On the other hand, it has been demonstrated that neutron fluxes can be used as a proxy for composition: thermal neutrons are strongly attenuated by absorbing elements such as iron, titanium, chlorine, gadolinium, and samarium; on the contrary, the fast neutron flux increases in presence of high-atomic mass elements such as iron or titanium. For a dry and airless body it is known that the ratio of epithermal over fast neutron counts is correlated to the ratio of thermal over fast neutron counts. This correlation leads to a unique parameter, which characterizes the various soil compositions. A similar behaviour has been observed within our subset of NS data. Effects of hydrogen and carbon are quite obvious, allowing us to focus on secondary components, which are driven by soil composition. From there, we derived four provinces besides the poles. The first province is made of H-rich equatorial regions (Arabia Terra and south of Lucus Planum). The second and third provinces are found north and south of the crustal

  1. Interpretation of detailed aerial gamma-ray survey, Jabal Ashirah area, southeastern Arabian Shield, Kingdom of Saudi Arabia

    USGS Publications Warehouse

    Duval, J.S.

    1987-01-01

    A detailed aerial gamma-ray spectrometric survey of the Jabal Ashirah area in the southeastern Arabian Shield has been analyzed using computer-classification algorithms. The analysis resulted in maps that show radiometric map units and gamma-ray anomalies indicating the presence of possible concentrations of potassium and uranium. The radiometric-unit map was interpreted to 'produce a simplified radiolithic map that was correlated with the mapped geology. The gamma-ray data show uranium anomalies that coincide with a tin-bearing granite, but known gold and nickel mineralization do not have any associated gamma-ray signatures.

  2. Application of mobile gamma-ray spectrometry for soil mapping

    NASA Astrophysics Data System (ADS)

    Werban, Ulrike; Lein, Claudia; Pohle, Marco; Dietrich, Peter

    2017-04-01

    Gamma-ray measurements have a long tradition for geological surveys and deposit exploration using airborne and borehole logging systems. For these applications, the relationships between the measured physical parameter - the concentration of natural gamma emitters 40K, 238U and 232Th - and geological origin or sedimentary developments are well described. Thus, Gamma-ray spectrometry seems a useful tool for carrying out spatial mapping of physical parameters related to soil properties. The isotope concentration in soils depends on different soil parameters (e.g. geochemical composition, grain size fractions), which are a result of source rock properties and processes during soil geneses. There is a rising interest in the method for application in Digital Soil Mapping or as input data for environmental, ecological or hydrological modelling, e.g. as indicator for clay content. However, the gamma-ray measurement is influenced by endogenous factors and processes like soil moisture variation, erosion and deposition of material or cultivation. We will present results from a time series of car borne gamma-ray measurements to observe heterogeneity of soil on a floodplain area in Central Germany. The study area is characterised by high variations in grain size distribution and occurrence of flooding events. For the survey, we used a 4 l NaI(Tl) detector with GPS connection mounted on a sledge, which is towed across the field sites by a four-wheel-vehicle. The comparison of data from different dates shows similar structures with small variation between the data ranges and shape of structures. We will present our experiences concerning the application of gamma-ray measurements under variable field conditions and their impacts on data quality.

  3. Gamma ray spectrometry of LDEF samples at SRS

    NASA Technical Reports Server (NTRS)

    Winn, Willard G.

    1991-01-01

    A total of 31 samples from Long Duration Exposure Facility (LDEF), including materials of Al, V, and steel trunnions were analyzed by ultralow level gamma spectrometry. The study quantified particle induced activations of Na-22, Sc-46, Cr-51, Mn-54, Co-56, Co-57, Co-58, and Co-60. The samples of trunnion sections exhibited increasing activity toward the outer end of the trunnion and decreasing activity toward its radial center. The trunnion sections did not include an end piece that collects noticeable Be-7 on its leading surface. No significant Be-7 was detected in the samples analyzed. The most sensitive analyses were performed with a 90 pct. efficient HPGe gamma ray detector, which is enclosed in a purged active/passive active shield.

  4. Airborne gamma spectrometry--towards integration of European operational capability.

    PubMed

    Toivonen, Harri

    2004-01-01

    Airborne gamma spectrometry is an excellent tool for finding out in a timely manner the extent and magnitude of the dispersion of radioactive materials resulting from a nuclear disaster. To utilise existing European airborne monitoring capabilities for multilateral assistance in an accident is a complex administrative and technical matter. Several international exercises have been organised demonstrating the capability to cooperate. However, efficient mutual assistance between European countries requires conceptual work, standards and harmonisation of software. A unified radiological vocabulary and data exchange format in XML need to be developed. A comprehensive database is essential for data assimilation. An operations centre is needed for management and planning of surveys. Copyright 2004 Oxford University Press

  5. In-situ gamma spectrometry in environmental monitoring.

    PubMed

    Kluson, J

    2010-01-01

    In-situ gamma spectrometry (scintillation or semiconductor) can be used effectively for monitoring natural and man-made radionuclide concentrations, together with the corresponding photon fields, in the environment and in workplaces. It is applied in operational and emergency monitoring of nuclear facilities, waste storage facilities and the uranium industry, in radioactive contamination measurements and mapping, environmental, radiohygienic and radiation safety studies, etc. Methods for processing and interpreting data, experimental techniques (ground or airborne arrangement), calibration and verification and examples of applications are discussed in this paper. Copyright 2009 Elsevier Ltd. All rights reserved.

  6. Carborne gamma-ray spectrometry. Calibration and applications.

    PubMed

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

    2006-08-01

    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 m x 62 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.

  7. Gamma ray spectrometry of LDEF samples at SRL

    NASA Technical Reports Server (NTRS)

    Winn, Willard G.

    1992-01-01

    A total of 31 samples from the Long Duration Exposure Facility (LDEF), including materials of aluminum, vanadium, and steel trunnions were analyzed by ultra-low-level gamma spectrometry. The study quantified particle induced activations of Na-22, Sc-46, Cr-51, Mn-54, Co-56, Co-57, Co-58, and Co-60. The samples of trunnion sections exhibited increasing activity toward the outer end of the trunnion and decreasing activity toward its radial center. The trunnion sections did not include end pieces, which were reported to collect noticeable Be-7 on their leading surfaces. No significant Be-7 was detected in the samples analyzed.

  8. Cadium-Zinc-Telluride (CZT) Gamma Ray Spectrometry

    SciTech Connect

    William Quam

    2001-09-01

    This report describes CZT crystals and their use in large arrays for generation of gamma ray spectra. Laboratory spectra will be shown together with spectra accumulated by various battery powered portable instruments (see Appendix A). One of these portable instruments was specifically constructed to minimize power consumption and yet provide reasonable isotope identification capability. Detailed data will be presented covering gamma energy resolution, gamma peak shapes, system background, and detector efficiency. Nearly all data were taken with very small crystals of CZT; cubes 5 mm on a side. A few spectra will be presented from cylindrical crystals of about the same size (see Appendix A). The small crystal size leads to low counting rates and extended counting times for reliable isotope identification. We have addressed this problem by using arrays of CZT crystals, initially two crystals and, at present, arrays of eight crystals. Data will be shown relating spectral parameters for these two arrays. System MDA is one way of combining resolution, efficiency, and background that will enable direct comparison of various detector types for individual isotope identification. We have calculated the MDA for an early dual crystal array and the current eight crystal array. Data derived from each array will be presented. In addition, it is possible to extrapolate the MDA methodology to much larger arrays. A 32-crystal array is under construction and extrapolations to 256 and 1024 crystals are considered possible. Estimated MDA values for these larger arrays are also presented. Several 8-crystal arrays have been constructed and versions have been incorporated into portable instruments. Descriptions of these small instruments are given covering physical size, weight, and general configuration. These instruments have been tested for shock and temperature effects and data will be presented on the results of these tests. The MDA concept will also allow extrapolation to large

  9. Guide to plutonium isotopic measurements using gamma-ray spectrometry

    SciTech Connect

    Lemming, J.F.; Rakel, D.A.

    1982-08-26

    Purpose of this guide is to assist those responsible for plutonium isotopic measurements in the application of gamma-ray spectrometry. Objectives are to promote an understanding of the measurement process, including its limitations and applicability, by reviewing the general features of a plutonium spectrum and identifying the quantities which must be extracted from the data; to introduce state-of-the-art analysis techniques by reviewing four isotopic analysis packages and identifying their differences; to establish the basis for measurement control and assurance by discussing means of authenticating the performance of a measurement system; and to prepare for some specific problems encountered in plutonium isotopic analyses by providing solutions from the practical experiences of several laboratories. 29 references, 12 figures, 17 tables.

  10. High-resolution gamma-ray spectrometry in uranium exploration

    USGS Publications Warehouse

    Moxham, Robert M.; Tanner, Allan B.

    1977-01-01

    Sedimentary-type uranium deposits accumulate at favorable sites along a migration path which may be kilometers in length. Their source is a large volume of rock from which the uranium has been leached. The geochemical mobilities and half lives of uranium and its daughter products vary widely so that they are transported from the source rocks, at different rates, along the migration path to their ultimate site. The radioactive disequilibrium resulting from this process has been well documented in the immediate vicinity of ore deposits, and disequilibrium is commonly recorded on gamma-ray logs up the hydraulic gradient from uranium ore. Little is known about the state of secular equilibrium in the leached host rocks, which often represent the only part of the migration path that is at or near the surface and is thus most accessible to the exploration geophysicist. High-resolution gamma-ray spectrometry provides a means of investigating the disequilibrium associated with uranium leaching and migration. Direct measurement of uranium can be made by this method, and the equivalent weight percents can be determined for six of the seven daughter-product decay groups that characterize the state of radioactive equilibrium. The technique has been used quantitatively in laboratory studies, where the results compare favorably with radiochemical analyses; field experiments suggest that semi-quantitative data may be obtained at the outcrop.

  11. Determination of the measurement threshold in gamma-ray spectrometry.

    PubMed

    Korun, M; Vodenik, B; Zorko, B

    2017-03-01

    In gamma-ray spectrometry the measurement threshold describes the lover boundary of the interval of peak areas originating in the response of the spectrometer to gamma-rays from the sample measured. In this sense it presents a generalization of the net indication corresponding to the decision threshold, which is the measurement threshold at the quantity value zero for a predetermined probability for making errors of the first kind. Measurement thresholds were determined for peaks appearing in the spectra of radon daughters (214)Pb and (214)Bi by measuring the spectrum 35 times under repeatable conditions. For the calculation of the measurement threshold the probability for detection of the peaks and the mean relative uncertainty of the peak area were used. The relative measurement thresholds, the ratios between the measurement threshold and the mean peak area uncertainty, were determined for 54 peaks where the probability for detection varied between some percent and about 95% and the relative peak area uncertainty between 30% and 80%. The relative measurement thresholds vary considerably from peak to peak, although the nominal value of the sensitivity parameter defining the sensitivity for locating peaks was equal for all peaks. At the value of the sensitivity parameter used, the peak analysis does not locate peaks corresponding to the decision threshold with the probability in excess of 50%. This implies that peaks in the spectrum may not be located, although the true value of the measurand exceeds the decision threshold.

  12. Extraction of Point Source Gamma Signals from Aerial Survey Data Taken over a Las Vegas Nevada Residential Area

    SciTech Connect

    Thane J. Hendricks

    2007-05-01

    Detection of point-source gamma signals from aerial measurements is complicated by widely varying terrestrial gamma backgrounds, since these variations frequently resemble signals from point-sources. Spectral stripping techniques have been very useful in separating man-made and natural radiation contributions which exist on Energy Research and Development Administration (ERDA) plant sites and other like facilities. However, these facilities are generally situated in desert areas or otherwise flat terrain with few man-made structures to disturb the natural background. It is of great interest to determine if the stripping technique can be successfully applied in populated areas where numerous man-made disturbances (houses, streets, yards, vehicles, etc.) exist.

  13. Use of airborne gamma-ray spectrometry for kaolin exploration

    NASA Astrophysics Data System (ADS)

    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.

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

    SciTech Connect

    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.

  15. Demonstration of lightweight gamma spectrometry systems in urban environments.

    PubMed

    Cresswell, A J; Sanderson, D C W; Harrold, M; Kirley, B; Mitchell, C; Weir, A

    2013-10-01

    Urban areas present highly complex radiation environments; with small scale features resulting from different construction materials, topographic effects and potential anthropogenic inputs from past industrial activity or other sources. Mapping of the radiation fields in urban areas allows a detailed assessment of exposure pathways for the people who live and work there, as well as locating discrete sources of activity that may warrant removal to mitigate dose to the general public. These areas also present access difficulties for radiometric mapping using vehicles or aircraft. A lightweight portable gamma spectrometry system has been used to survey sites in the vicinity of Glasgow to demonstrate the possibilities of radiometric mapping of urban areas, and to investigate the complex radiometric features such areas present. Variations in natural activity due to construction materials have been described, the presence of (137)Cs used to identify relatively undisturbed ground, and a previously unknown NORM feature identified. The effect of topographic enclosure on measurements of activity concentration has been quantified. The portable system is compared with the outputs that might be expected from larger vehicular or airborne systems. For large areas airborne surveys are the most cost effective approach, but provide limited spatial resolution, vehicular surveys can provide sparse exploratory data rapidly or detailed mapping of open areas where off-road access is possible. Backpack systems are ideally suited to detailed surveys of small areas, especially where vehicular access is difficult.

  16. Basic characterization of 233U: Determination of age and 232U content using sector field ICP-MS, gamma spectrometry and alpha spectrometry

    NASA Astrophysics Data System (ADS)

    Ramebäck, H.; Nygren, U.; Lagerkvist, P.; Verbruggen, A.; Wellum, R.; Skarnemark, G.

    2008-03-01

    The possibility to determine the age, i.e. the time since the last chemical separation, of 233U was studied using two fundamentally different measurement techniques: inductively coupled plasma mass spectrometry (ICP-MS) and gamma spectrometry. Moreover, the isotope ratio 232U/233U was measured using both alpha spectrometry and gamma spectrometry. For the two materials analysed, all measurement results were in agreement, i.e. consistent within the combined uncertainties. One of the materials was also measured using gamma spectrometry under field conditions. This measurement was also in agreement with the other results on this material.

  17. Recovery and reanalysis of archived airborne gamma spectrometry data from the 1991 Dounreay survey.

    PubMed

    Cresswell, A J

    2012-01-01

    Archived Airborne Gamma Spectrometry (AGS) data from the 1991 NIREX characterisations of Caithness have been recovered. The separate gamma spectrometry and positional data streams for approximately 120,000 measurements have been combined into a single data stream using the European Radiometrics and Spectrometry (ERS) data format. An analysis using working calibration coefficients and spectral stripping procedure has verified that the original survey recorded high quality data. The converted data stream is in a format more accessible to future research use, including evaluation of environmental change in the Caithness region.

  18. Study of gamma spectrometry laboratory measurement in various sediment and vulcanic rocks

    NASA Astrophysics Data System (ADS)

    Nurhandoko, Bagus Endar B.; Kurniadi, Rizal; Rizka Asmara Hadi, Muhammad; Rizal Komara, Insan

    2017-01-01

    Gamma-ray spectroscopy is the quantitative study of the energy spectra of gamma-ray sources. This method is powerful to characterize some minerals, especially to differentiate rocks which contains among Potassium, Uranium, dan Thorium. Rock contains radioactive material which produce gamma rays in various energies and intensities. When these emissions are detected and analyzed with a spectroscopy system, a gamma-ray energy spectrum can be used as indicator for mineral content of rock. Some sediment and vulcanic rock have been collected from East Java Basin. Samples are ranging from Andesite vulcanics, Tuff, Shale, various vulcanic clay and Alluvial clay. We present some unique characteristics of gamma spectrometry in various sedimentar and vulcanic rocks of East Java Basins. Details contents of gamma ray spectra give enrichments to characterize sample of sediment and vulcanic in East Java. Weathered vulcanic clay has lower counting rate of gamma ray than alluvial deltaic clay counting rate. Therefore, gamma spectrometrometry can be used as tool for characterizing the enviroment of clay whether vulcanic or alluvial-deltaic. This phenomena indicates that gamma ray spectrometry can be as tool for characterizing the clay whether it tends to Smectite or Illite

  19. A simple method for the absolute determination of uranium enrichment by high-resolution gamma spectrometry.

    PubMed

    Korob, R O; Blasiyh Nuño, G A

    2006-05-01

    A simple method for the determination of uranium enrichment using high-resolution gamma spectrometry is presented in this paper. The method relies solely on the gamma-ray emission probabilities of 235U and 234mPa, and an iterative procedure for the least squares fit of a polynomial to a set of experimentally determined data. To ensure the reliability of the 234mPa gamma-ray emission probabilities employed, a new determination of these probabilities was carried out using a combination of gamma spectrometry and Cerenkov counting of a purified 234Th solution. Using these new data, a maximum difference of approximately 5% has been found between the experimental and declared uranium enrichment in a set of solid and liquid samples containing uranium compounds.

  20. The Dortmund Low Background Facility - Low-background gamma ray spectrometry with an artificial overburden.

    PubMed

    Gastrich, Holger; Gößling, Claus; Klingenberg, Reiner; Kröninger, Kevin; Neddermann, Till; Nitsch, Christian; Quante, Thomas; Zuber, Kai

    2016-06-01

    The Dortmund Low Background Facility is an instrument for low-level gamma ray spectrometry with an artificial overburden of ten meters of water equivalent, an inner shielding, featuring a neutron absorber, and an active muon veto. An integral background count rate between 40keV and 2700keV of (2.528±0.004)counts/(kgmin) enables low-background gamma ray spectrometry with sensitivities in the range of some 10mBq/kg within a week of measurement time.

  1. In-flight, online processing and mapping of airborne gamma spectrometry data

    NASA Astrophysics Data System (ADS)

    Bucher, Benno; Rybach, Ladislaus; Schwarz, Georg

    2005-03-01

    Airborne gamma spectrometry is a technique especially useful for environmental monitoring and emergency preparedness. Because time is a critical factor in emergency response a fast data processing and mapping software is needed, which also supports online monitoring and data processing features. Therefore a new online data processing and mapping software was developed, which also displays successfully the gamma spectra, the ground activity and the topographical data. The software was successfully tested during various survey flights.

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

    DOEpatents

    Hartwell, Jack K.; Goodwin, Scott G.; Johnson, Larry O.; Killian, E. Wayne

    1990-01-01

    An improved system for gamma-ray spectroscopy characterized by an interface module that controls the injection of electronic pulses as well as separation logic that enables storage of pulser events in a region of the spectrum of a multichannel analyzer distinct from the region reserved for storage of gamma-ray events. The module accomplishes this by tagging pulser events (high or low) injected into the amplification circuitry, adding an offset to the events so identified at the time the events are at the output of the analog to digital converter, and storing such events in the upper portion of the spectrum stored in the multichannel analyzer. The module can be adapted for use with existing gamma-ray spectroscopy equipment to provide for automatic analyses of radioisotopes.

  3. On homogeneity approximation in calibration of gamma-spectrometry assessment of bulk samples.

    PubMed

    Sima, Octavian

    2017-08-03

    The effect of the intrinsic inhomogeneity of a sample on the efficiency for the measurement of the sample by gamma-ray spectrometry is studied. The difference between the efficiency for the inhomogeneous sample and the efficiency for a sample made from the equivalent homogeneous matrix is evaluated. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Airborne gamma-ray spectrometry in uranium exploration

    NASA Astrophysics Data System (ADS)

    Raghuwanshi, S. S.

    1992-07-01

    Uranium exploration is of paramount importance to India to maximize the indigeneous resources to meet the ever increasing demand for energy. Comprehensive regional and local zones of uranium mineralization are needed to be resolved. Such data comprise information on radioactivity in various energy ranges and on lithological knowledge. Airborne gamma-ray spectrometric techniques are particularly suited to provide spatial information. This review briefly discusses the conventional data presentation, statistically significant maps and the schemes suitable for classification of mineralized zones. A brief introduction is provided to airborne gamma-ray data, their acquisition, analysis, processing and interpretation to bring out their role in designing suitable models of uranium resources. State-of-the-art in uranium exploration covers radiometric mapping through airborne gamma-ray surveys. Through the examples of the Indian work done during this decade, the state-of-the-art and its usefulness in the country has been illustrated. It is concluded that the high sensitivity airborne gamma-ray spectrometric surveys coupled with modern methods of data analysis can further narrow down the targets.

  5. Digital approach to high rate gamma-ray spectrometry

    SciTech Connect

    Korolczuk, Stefan; Mianowski, Slawomir; Rzadkiewicz, Jacek; Sibczynski, Pawel; Swiderski, Lukasz; Szewinski, Jaroslaw; Zychor, Izabella

    2015-07-01

    Basic concepts and preliminary results of creating high rate digital spectrometry system using efficient ADCs and latest FPGA are presented as well as a comparison with commercially available devices. The possibility to use such systems, coupled to scintillators, in plasma experiments is discussed. (authors)

  6. Characterization of coal and charcoal by alpha-particle and gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    Carrasco Lourtau, A. M.; Rubio Montero, M. P.; Jurado Vargas, M.

    2015-11-01

    Although coal and charcoal have similar physical and chemical characteristics, there are several crystallographic procedures used to distinguish and characterize them. But if the matrix is crushed, there is no standard procedure to distinguish coal from charcoal. In this work, a procedure to characterize coal and charcoal samples based on the radioactive content is proposed. The first assay is by gamma-ray spectrometry, which allows a part of the radioactive content to be determined rapidly and non-destructively. Then, alpha-particle spectrometry is applied to assay the content of those radionuclides which are difficult to determine precisely by gamma-ray spectrometry. This second technique requires prior chemical purification of the carbon sample in order to separate the corresponding radionuclides of interest.

  7. Some applications of gamma absorptiometry and spectrometry for the control of nuclear materials

    NASA Astrophysics Data System (ADS)

    Guery, M.

    1991-02-01

    In nuclear fuels, and neutrons absorbers used in control rods, the thermal power generated is locally dependent on the concentration of the fissile or absorbing nucleus. In order to control the homogeneity of such materials, non-destructive methods using either gamma absorptiometry or gamma spectrometry were developed; some applications of these methods are presented in this paper. The fuel of the High Temperature Reactor (HTR) is frequently composed of UO 2 and ThO 2 spherical particles dispersed in a carbon matrix; the axial distribution of the particles along the fuel rods can be controlled in two ways: with gamma absorptiometry the heavy elements atoms (U+Th) can be detected but without discrimination between U and Th; with gamma spectrometry, separate distributions of uranium and thorium, deduced from the intensity of characteristic gamma rays are obtained. In nuclear power plants (PWR, FBR) the control rods are made usually with boron carbide (B 4C) pellets. By mean of gamma absorptiometry scanning the density distribution along the axis and the radius of the pellets are obtained. The originality of the method consists in the use of a self-calibration process, then the knowledge of the mass absorption coefficient is not required to perform the examinations. A computerized apparatus has been developed for these controls.

  8. Monitoring radioactive plumes by airborne gamma-ray spectrometry

    SciTech Connect

    Grasty, R.L.; Hovgaard, J.; Multala, J.

    1996-06-01

    Airborne gamma-ray spectrometer surveys using large volume sodium-iodide detectors are routinely flown throughout the world for mineral exploration and geological mapping. Techniques have now been developed to detect and map man-made sources of radiation. In Canada, airborne gamma-rays surveys have been flown around nuclear reactors to map {sup 41}Ar plumes from nuclear reactors and to calculate the dose rate at ground level. In May 1986, the Finnish Geological survey aircraft flew through a radioactive plume from the Chernobyl nuclear accident. As the aircraft flew through the plume, the aircraft became increasingly contaminated. By measuring the final aircraft contamination, the activity of the plume could be separated from the contamination due to the aircraft. Within 1 h of encountering the plume, the aircraft activity was comparable to the maximum levels found in the plume. From an analysis of the gamma-ray spectra, the concentration of {sup 131}I and {sup 140}La within the plume were calculated as a function of time.

  9. Gamma-ray spectrometry of LDEF samples at SRL

    SciTech Connect

    Winn, W.G.

    1991-07-22

    A total of 31 samples from the Long Duration Exposure Facility (LDEF), including materials of aluminum, vanadium, and steel trunnions were analyzed by ultra-low-level gamma spectroscopy. The study quantified particle induced activations of {sup 22}Na, {sup 46}Sc, {sup 51}Cr, {sup 54}Mn, {sup 56}Co, {sup 57}Co, {sup 58}Co, and {sup 60}Co. The samples of trunnion sections exhibited increasing activity toward the outer end of the trunnion and decreasing activity toward its radial center. The trunnion sections did not include end pieces, which have been reported to collect noticeable {sup 7}Be on their leading surfaces. No significant {sup 7}Be was detected in the samples analyzed. The Underground Counting Facility at Savannah River Laboratory (SRL) was used in this work. The facility is 50 ft. underground, constructed with low-background shielding materials, and operated as a clean room. The most sensitive analyses were performed with a 90%-efficient HPGe gamma-ray detector, which is enclosed in a purged active/passive shield. Each sample was counted for one to six days in two orientations to yield more representative average activities for the sample. The non-standard geometries of the LDEF samples prompted the development of a novel calibration method, whereby the efficiency about the samples surfaces (measured with point sources) predicted the efficiency for the bulk sample.

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

    SciTech Connect

    Wilhelm, Emilien; Gutierrez, Sebastien; Reboli, Anne; Menard, Stephanie; Nourreddine, Abdel-Mjid; Arbor, Nicolas

    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)

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

    SciTech Connect

    Li, T.K.; Parker, J.L. ); Kuno, Y.; Sato, S.; Kurosawa, A.; Akiyama, T. )

    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.

  12. Metrological characterization of the ADONIS system used in gamma-ray spectrometry.

    PubMed

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

    2004-01-01

    In gamma-ray spectrometry, new acquisition systems based on digital signal processing are now commercially available. In order to determine their performance at high count rates, the Commissariat à l'Energie Atomique (CEA), Laboratoire National Henri Becquerel has tested several of these systems. These tests have clearly shown that the performance levels announced by the manufacturers were generally not met. It was therefore a logical step to include the Atelier de DévelOppement Numérique pour l'Instrumentation en Spectrométrie (ADONIS) system in these tests. ADONIS is the new numerical system for gamma-ray spectrometry, developed by the CEA Service d'Instrumentation et d'Application des Rayonnements.

  13. Advances in room-temperature solid-state gamma-ray spectrometry

    SciTech Connect

    Iwanczyk, J.S.

    1983-01-01

    This article presents a review and analysis of different concepts of gamma-ray spectrometry using room-temperature solid-state detectors. The classical approach involving the use of a charge-sensitive preamplifier and attempting to collect all the ionization charge produced by the gamma ray is analyzed and discussed in terms of the charge transport parameters of the most promising compound semiconductor materials. It is concluded that compound semiconductor detector materials having a large disparity between the ..mu.. tau products for electrons and holes (such as HgI/sub 2/ and CdTe) will have rather poor energy resolution if the classical method of spectrometry requiring full charge collection is employed. 30 references.

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

    PubMed

    Sanderson, D C W; Cresswell, A J; Scott, E M; Lang, J J

    2004-01-01

    Airborne gamma spectrometry (AGS) is being increasingly recognised as an important means for mapping environmental radioactivity in emergency response. Progress has been made in recent years towards methodological convergence and cooperation between European teams. Recently, an international comparison was undertaken in SW Scotland in 2002 to evaluate AGS and ground-based methods. Teams from 18 institutions in 10 European countries attended, collecting some 140,000 AGS spectra, with 750 laboratory gamma spectrometry analyses and 120 in situ observations from the ground sites. Comparisons between AGS and ground-based methods have confirmed the validity of AGS protocols. A composite mapping task, where AGS teams recorded data over adjacent parts of a 90 x 40 km2 area within a few days, confirmed the ability of teams to work together in an effective manner. This paper provides a summary of the results of the exercise. These demonstrate the operational capabilities of European AGS teams and confirm the quantitative nature of the method.

  15. Aerial Magnetic, Electromagnetic, and Gamma-ray Survey, Berrien County, Michigan

    USGS Publications Warehouse

    Duval, Joseph S.; Pierce, Herbert A.; Daniels, David L.; Mars, John L.; Webring, Michael W.; Hildenbrand, Thomas G.

    2002-01-01

    This publication includes maps, grids, and flightline databases of a detailed aerial survey and maps and grids of satellite data in Berrien County, Michigan. The purpose of the survey was to map aquifers in glacial terrains. This was accomplished by using a DIGHEMVRES mufti-coil, mufti-frequency electromagnetic system supplemented by a high sensitivity cesium magnetometer and 256-channel spectrometer. The information from these sensors was processed to produce maps, which display the conductive, magnetic and radioactive properties of the survey area. A GPS electronic navigation system ensured accurate positioning of the geophysical data. This report also includes data from the advanced spaceborne thermal emission and reflection (ASTER) radiometer. ASTER measures thermal emission and reflection data for 14 bands of the spectrum.

  16. The potential of gamma-ray spectrometry as supplementary information for mapping central European soils

    NASA Astrophysics Data System (ADS)

    Schuler, U.; Bock, M.; Baritz, R.; Willer, J.; Pickert, E.; Kardel, K.; Herrmann, L.

    2012-04-01

    Permanently updated soil maps are needed inter alia for the prediction of landslide hazards, flooding and drought effects, land degradation monitoring, and precision farming. Since comprehensive and intensive field mapping is not affordable, alternative mapping approaches are required. A promising tool, with quite unrecognised potential for modern soil science is gamma-ray spectrometry. As the radioelements potassium, thorium and uranium respond differently to soil forming processes, it should be possible to infer from their concentration on weathering status, and after calibration on soil properties and types. This paper aims to investigate the potential of airborne gamma spectrometry for mapping of central European soils and soil properties. The study was conducted for a test site in Southern Saxony, Germany, 140*85 km wide, representing diverse soil landscapes. Seven different petrographic training and validation areas were chosen each. To assess the potential of gamma-ray spectrometry as additional data layer, predictions were carried out (i) with and (ii) without radiometric data. The outputs were compared with independent soil information of the validation areas. Both prediction runs used the following predictors: elevation, slope, curvature, planform curvature, profile curvature, terrain ruggedness index, relative altitude, vertical distance above drainage network, wetness index, and convergence index. As additional predictor parent material derived from a reclassification of the official geological map (1:1M scale) was used. As radiometric properties potassium, thorium and uranium were used. The radiometric raster datasets were generated by universal kriging using relative altitude as covariate. Training and validation datasets were selected from a comprehensive dataset representing more than 14.000 point data. Point data include soil types and substrates, and for more than 800 sites soil profiles with analysed texture, pH, exchangeable cations, nutrients

  17. Determination of impurities in (124)I samples by high resolution gamma spectrometry.

    PubMed

    de Almeida, M C M; da Silva, R L; Delgado, J U; Poledna, R; de Araújo, M T F; Laranjeira, A S; de Veras, E; Braghirolli, A M S; Dos Santos, G R; Lopes, R T

    2016-03-01

    (124)I is a radionuclide used in the diagnosis of tumors. The National Health Agency requires identification and activity measurement of impurities. Using gamma spectrometry with an efficiency calibrated high-purity germanium detector, impurities (125)I and (126)I in an (1)(24)I production sample were identified. Activity ratios of (125)I and (126)I to (124)I were approximately 0.5% and 98%, respectively. Published by Elsevier Ltd.

  18. Early detection of radioactive fallout by gamma spectrometry.

    PubMed

    Aage, H K; Korsbech, U; Bargholz, K

    2003-01-01

    Radioactive fallout should be detected as early as possible. A new and efficient method for detection of low-level irradiation from manmade radioactivity is developed. Radiation abnormalities are detectable down to air kerma rates of 0.5 to 1.0 nGy h(-1) for 137Cs and even lower for 131I. For multi-gamma energy radioactivity the detection level is 2.6-3.5 nGy h(-1). A standard NaI detector and a 512-channel analyser are used together with noise adjusted singular value decomposition (NASVD). Statistical noise is removed and the measured spectra are reproduced using spectral components produced by NASVD. Stripping is not used and false alarms due to washout of atmospheric radon progeny are almost eliminated. Detection levels and the criteria for setting warning and alarm levels are discussed. The method may also be useful in other situations, for example where low-level signals from radioactive sources need to be detected.

  19. NMIS With Gamma Spectrometry for Attributes of Pu and HEU, Explosives and Chemical Agents

    SciTech Connect

    Mihalczo, J. T.; Mattingly, J. K.; Mullens, J. A.; Neal, J. S.

    2002-05-10

    The concept for the system described herein is an active/passive Nuclear Materials Identification System{sup 2} (NMIS) that incorporates gamma ray spectrometry{sup 3}. This incorporation of gamma ray spectrometry would add existing capability into this system. This Multiple Attribute System can determine a wide variety of attributes for Pu and highly enriched uranium (HEU) of which a selected subset could be chosen. This system can be built using commercial off the shelf (COTS) components. NMIS systems are at All-Russian Scientific Research Institute of Experimental Physics (VNIIEF) and Russian Federal Nuclear Center Institute of Technical Physics, (VNIITF) and measurements with Pu have been performed at VNIIEF and analyzed successfully for mass and thickness of Pu. NMIS systems are being used successfully for HEU at the Y-12 National Security Complex. The use of active gamma ray spectrometry for high explosive HE and chemical agent detection is a well known activation analysis technique, and it is incorporated here. This report describes the system, explains the attribute determination methods for fissile materials, discusses technical issues to be resolved, discusses additional development needs, presents a schedule for building from COTS components, and assembly with existing components, and discusses implementation issues such as lack of need for facility modification and low radiation exposure.

  20. Determination of saponins in aerial parts of barrel medic (Medicago truncatula) by liquid chromatography-electrospray ionization/mass spectrometry.

    PubMed

    Kapusta, Ireneusz; Janda, Bogdan; Stochmal, Anna; Oleszek, Wieslaw

    2005-10-05

    Triterpene saponins from aerial parts of Medicago truncatula cv. Jemalong A-17, M. truncatula Gaertn.var. longispina Urb., and M. truncatula Gaertn. var. truncatula were profiled and quantified using reverse-phase liquid chromatography with on-line photodiode array detection and electrospray ionization mass spectrometry (LC-PDA/ESI/MS/MS). The determination was based on standard curves obtained for the 18 available saponin standards, previously isolated from Jemalong A-17. Aerial parts of all three subspecies contained 17 saponins previously identified and also a substantial amount of astragaloside VIII (3-GlcA-Xyl-Rha soyasapogenol B), not previously reported in M. truncatula. The compositions of saponin mixtures were very similar in the three subspecies with three dominant groups, recognized as zanhic acid, medicagenic acid, and soyasapogenol glycosides. Relative proportions of these three groups were also similar in the three subspecies: var. longispina had 49.5, 48.1, and 2.4%; var. truncatula, 41.5, 53.4, and 5.1%; and Jemalong A-17, 42.1, 56.6, and 1.3% of zanhic acid, medicagenic acid, and soyasapogenol glycosides, respectively. Jemalong A-17 had 30% lower total content of saponins as compared to M. truncatula var. longispina and M. truncatula var. truncatula; in relation to the dry matter, var. longispina contained 0.22%, var. truncatula, 0.22%, and Jemalong A-17, 0.15% dry matter of saponins. If one takes into consideration that this determination was performed on spring-collected samples, it can be concluded that the concentration of saponins in M. truncatula is similar to the concentration in alfalfa (Medicago sativa); the proportions of the three groups of saponins in these species are slightly different from those found in alfalfa, having a higher content of zanhic acid glycosides.

  1. Initial recommendations for restricting gamma-ray spectrometry measurements of radionuclides for on-site inspections

    SciTech Connect

    Buckley, W F; Kreek, S A; Wild, J F

    1998-11-06

    The US paper "Radionuclide Sampling, Sample Handling and Analytical Laboratory Equipment for Comprehensive Test Ban Treaty On-Site Inspections," CTBT/PC/V/OSI/WSII/PR/29 identified the radionuclides of interest to an OS1 as 144Ce, 147Nd, 141Ce, 149Ba140La), 95 Zr(95Nb), 131mXe, 133mXe, 133gXe, 135gXe, and 37Ar. All of these nuclides (except 37Ar) can be measured via some form of conventional or coincidence-based gamma-ray spectrometry. The non-gaseous radionuclides [144Ce, 147Nd, 141Ce, 140Ba(140La), and 95Zr(95Nb)] can be measured via conventional high-resolution gamma-ray spectrometry using a shielded, high-purity germanium (HPGe) detector. The gaseous radionuclides 131mXe, 133mXe, 133gXe, and 135gXe are best measured (after separation from their homologous elements) via a gamma & beta/electron coincidence technique such as that described in CTBT/WGB/TL-11/5 which could utilize either a HPGe or low-resolution (NaI(TI)) gamma-ray spectrometer to detect the gamma-ray/x-ray and a plastic scintillator to detect the beta particle/electron from the decay of the various Xe isotopes. The US paper CTBT/PC/V/IOSI/WSII/PR/29 (and other papers) identified a need to limit the information that can be extracted from high-resolution gamma-ray spectra to ensure that only information relevant to an OSI is accessible. The term "blinding" has been used to describe the need to limit the information available to the Inspection Team from the high-resolution gamma-ray measurement. A better term is "measurement restriction"; the need for restricting the information is particularly relevant to conventional high-resolution gamma-ray spectrometry measurements, but not to the gamma & beta/electron coincidence-type measurements

  2. Testing of regolith of celestial bolides with active neutron gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    Vostrukhin, Andrey; Mitrofanov, Igor; Golovin, Dmitry; Litvak, Maxim; Sanin, Anton

    2015-04-01

    Current space instruments for studying planet's surface include gamma ray spectrometers that detect natural radioactive isotopes as well as gamma-rays induced in subsurface by galactic cosmic rays. When measuring from celestial body's surface, statistics and amount of detected elements can be dramatically increased with active methods, where soil exposed to artificial flux of particles. One good example is the Russian Dynamic Albedo of Neutron (DAN) instrument onboard Martian Science Laboratory mission (Curiosity rover) developed in 2005-2011. It is the first active neutron spectrometer flown to another planet as part of a landed mission to investigate subsurface water distribution and which has now successfully operated for more than two years on the Martian surface. Presentation describes a number of space instruments for different landers and rovers being developed in Russian Space Research Institute for studying Moon and Mars, as well as method of active neutron and gamma spectrometry overview.

  3. Characterization of gamma irradiated petrolatum eye ointment base by headspace-gas chromatography-mass spectrometry.

    PubMed

    Hong, Lan; Altorfer, Hans

    2002-06-20

    The effects of gamma irradiation on petrolatum eye ointment base (EOB) and its ingredients (white petrolatum, liquid paraffin, and wool fat) were studied at different irradiation doses. Forty-one volatile radiolysis products were detected and identified by a combined system of headspace-gas chromatography-mass spectrometry (HS-GC-MS). The characteristics of the radiolysis products and the degradation pathway were discussed in each case, respectively. GC method demonstrates that the component distribution patterns of eye ointment as well as its individual ingredients have no differences before and after gamma irradiation. The influence of gamma treatment on EOB was quantitatively determined at 15, 25 and 50 kGy. The concentrations of the radiolysis products increase linearly with increasing doses. Both qualitative and quantitative data show that irradiated eye ointment is safe for human use.

  4. Use of Gamma Spectrometry Method for Environmental Monitoring in the area of NPP

    NASA Astrophysics Data System (ADS)

    Thinova, L.; Cechak, T.; Kluson, J.; Trojek, T.

    2006-05-01

    It is generally not possible to correctly determine the long and short term impact of human activity upon the environment, without thorough processing of data, obtained through monitoring. It was confirmed that such impact on the environment must be monitored over a long time period. The data obtained must be of high quality, an attribute assured by present state of scientific knowledge. One of the well established methods for monitoring atmospheric deposition of radionuclides in the environment is laboratory and in situ gamma spectrometry. With the aim to monitor an occurrence of a one-time escape or persistent release of fission products into the air, resulting from an operation of a nuclear plant, two types of monitoring are performed: i/ measurement of samples from the environment (Schreber moss, forest humus, pine bark, mushrooms and forest berries) using laboratory gamma spectrometry method in the range up to 3 MeV (those data are used for the trend analysis and for the construction of the contaminationmaps); ii/ in situ gama spectrometry for assessment dosimetry and spectrometry characteristic of photon-fields (those data are used for the dose rate calculation).

  5. Measurement of gamma radiation levels in soil samples from Thanjavur using gamma-ray spectrometry and estimation of population exposure.

    PubMed

    Senthilkumar, B; Dhavamani, V; Ramkumar, S; Philominathan, P

    2010-01-01

    This study assesses the level of terrestrial gamma radiation and associated dose rates from the naturally occurring radionuclides (232)Th, (238)U and (40)K in 10 soil samples collected from Thanjavur (Tamil Nadu, India) using gamma-ray spectrometry. The activity profile of radionuclides has clearly showed the existence of low level activity in Thanjavur. The geometric mean activity concentrations of (232)Th, (238)U and (40)K is 42.9+/-9.4 Bq.kg(-1), 14.7+/-1.7 Bq.kg(-1) and 149.5+/-3.1 Bq.kg(-1) respectively are derived from all the soil samples studied. The activity concentration of (232)Th, (238)U and (40)K in soil is due to the presence of metamorphic rocks like shale, hornblende-biotite gneiss and quartzofeldspathic gneiss in these areas. Gamma absorbed dose rates in air outdoors were calculated to be in the range between 32 nGy.h(-1) and 59.1 nGy.h(-1) with an arithmetic mean of 43.3 +/-9 nGy.h(-1). This value is lesser than the population weighted world-averaged of 60 nGy.h(-1). Inhabitants of Thanjavur are subjected to external gamma radiation exposure (effective dose) ranging between 39.2 and 72.6 muSv.y(-1) with an arithmetic mean of 53.1+/-11 muSv.y(-1). The values of the external hazard index determined from the soil radioactivity of the study area are less than the recommended safe levels.

  6. Radioactivity Levels and Gamma-Ray Dose Rate in Soil Samples from Kohistan (Pakistan) Using Gamma-Ray Spectrometry

    NASA Astrophysics Data System (ADS)

    Hasan, M. Khan; Ismail, M.; K., Khan; Akhter, P.

    2011-01-01

    The analysis of naturally occurring radionuclides (226Ra, 232Th and 40K) and an anthropogenic radionuclide 137Cs is carried out in some soil samples collected from Kohistan district of N.W.F.P. (Pakistan), using gamma-ray spectrometry. The gamma spectrometry is operated using a high purity Germanium (HPGe) detector coupled with a computer based high resolution multi channel analyzer. The specific activity in soil ranges from 24.72 to 78.48Bq·kg-1 for 226Ra, 21.73 to 75.28Bq·kg-1 for 232Th, 7.06 to 14.9Bq·kg-1 for 137Cs and 298.46 to 570.77Bq·kg-1 for 40K with the mean values of 42.11, 43.27, 9.5 and 418.27Bq·kg-1, respectively. The radium equivalent activity in all the soil samples is lower than the safe limit set in the OECD report (370Bq·kg-1). Man-made radionuclide 137Cs is also present in detectable amount in all soil samples. Presence of 137Cs indicates that the samples in this remote area also receive some fallout from nuclear accident in Chernobyl power plant in 1986. The internal and external hazard indices have the mean values of 0.48 and 0.37 respectively. Absorbed dose rates and effective dose equivalents are also determined for the samples. The concentration of radionuclides found in the soil samples during the present study is nominal and does not pose any potential health hazard to the general public.

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

    PubMed

    Wilhelm, Emilien; Gutierrez, Sébastien; Arbor, Nicolas; Ménard, Stéphanie; Nourreddine, Abdel-Mjid

    2016-11-01

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

  8. GEANT4 calibration of gamma spectrometry efficiency for measurements of airborne radioactivity on filter paper.

    PubMed

    Alrefae, Tareq

    2014-11-01

    A simple method of efficiency calibration for gamma spectrometry was performed. This method, which focused on measuring airborne radioactivity collected on filter paper, was based on Monte Carlo simulations using the toolkit GEANT4. Experimentally, the efficiency values of an HPGe detector were calculated for a multi-gamma disk source. These efficiency values were compared to their counterparts produced by a computer code that simulated experimental conditions. Such comparison revealed biases of 24, 10, 1, 3, 7, and 3% for the radionuclides (photon energies in keV) of Ce (166), Sn (392), Cs (662), Co (1,173), Co (1,333), and Y (1,836), respectively. The output of the simulation code was in acceptable agreement with the experimental findings, thus validating the proposed method.

  9. Evaluation of radiological data of some saturated fatty acids using gamma ray spectrometry

    NASA Astrophysics Data System (ADS)

    Kore, Prashant S.; Pawar, Pravina P.; Palani Selvam, T.

    2016-02-01

    Radiological parameters such as mass attenuation coefficients (μm), total attenuation cross section (σtot), molar extinction coefficient (ε), mass energy absorption coefficient (μen/ρ) and effective electronic cross section (σt, el) of saturated fatty acids, namely butyric acid (C4H8O2), caproic acid (C6H12O2), enanthic acid (C7H14O2), caprylic acid (C8H16O2), pelargonic acid (C9H18O2) and valeric acid (C5H10O2) were measured using NaI(Tl)-based gamma spectrometry. Radioactive sources used in the study are 57Co, 133Ba, 137Cs, 54Mn, 60Co and 22Na. Gamma ray transmission method in a narrow beam good geometry set up was used in the study. The measured data were compared against Win-XCOM-based data. The agreement is within 1%.

  10. Fluence Evaluations For Applications of In Situ Gamma-Ray Spectrometry in Non-Flat Terrain

    SciTech Connect

    Miller, Kevin M.

    1999-02-28

    Evaluations of gamma-ray fluence are made for source geometries that depart from the flat ground geometry that is used in standard applications of in situ spectrometry. Geometries considered include uniform source distributions for soil mounds on top of flat terrain, cylindrical wells, and rectangular trenches. The results indicate that scaling the standard fluence values for flat terrain by the ratio of solid angle subtended by the soil to 2π leads to fluence estimates that are accurate to within a few percent. Practical applications of in situ spectrometry in non-flat terrain also appears to be simplified by the fact that the angular correction factor for a typical coaxial detector in these geometries may typically be about the same as that computed for flat ground.

  11. Contribution of atmospherical radon to in-situ scintillation gamma spectrometry data.

    PubMed

    Klusoň, J; Thinová, L

    2011-08-01

    In-situ gamma spectrometry can be used for monitoring and determining natural and man-made radionuclide concentrations in the environment. The low detection limit of potential contaminants depends on the natural background variations, including variations in the atmospheric concentrations of radon and its decay products. The scintillation spectrometer response for atmospheric radon was simulated by the Monte Carlo method, and the results were compared with the experimental measurements over large water surfaces. The contributions of atmospheric radon to the natural background were assessed. 2010 Elsevier Ltd. All rights reserved.

  12. A new technique for processing airborne gamma ray spectrometry data for mapping low level contaminations.

    PubMed

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

    1999-12-01

    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 137Cs at levels often well below 1 kBq/m2 equivalent surface contamination. The limiting factors for obtaining reliable results are radon in the air, spectrum stability and accurate altitude measurements.

  13. Precipitation correction of airborne gamma-ray spectrometry data using monitoring profiles: methodology and case study

    NASA Astrophysics Data System (ADS)

    Ahl, Andreas; Motschka, Klaus; Slapansky, Peter

    2014-08-01

    Variations of soil moisture content caused by precipitation often complicate the interpretation of airborne gamma-ray spectrometry data. This is particularly the case in repeated surveys designed to monitor the change of near surface abundances of radioactive elements or in large and time-consuming surveys. To counter this precipitation effect we propose a correction method based on repeated survey flights over a monitoring profile. Assuming that the weather and the soil conditions at the monitoring profile are representative for the survey area, the weather dependent effect of soil moisture can be observed and sufficiently corrected.

  14. Determination of the neutron activation profile of core drill samples by gamma-ray spectrometry.

    PubMed

    Gurau, D; Boden, S; Sima, O; Stanga, D

    2017-08-04

    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.

  15. Measurements of activation induced by environmental neutrons using ultra low-level gamma-ray spectrometry.

    PubMed

    Martínez Canet, M J; Hult, M; Köhler, M; Johnston, P N

    2000-03-01

    The flux of environmental neutrons is being studied by activation of metal discs of selected elements. Near the earth's surface the total neutron flux is in the order of 10(-2) cm(-2)s(-1), which gives induced activities of a few mBq in the discs. Initial results from this technique, involving activation at ground level for several materials (W, Au, Ta, In, Re, Sm, Dy and Mn) and ultra low-level gamma-ray spectrometry in an underground laboratory located at 500 m.w.e., are presented. Diffusion of environmental neutrons in water is also measured by activation of gold at different depths.

  16. Low level activity determination by means of gamma spectrometry with respect to the natural background fluctuation.

    PubMed

    Dragounová, Lenka; Rulík, Petr

    2013-11-01

    The determination of low level activities of natural radionuclides from the uranium and thorium series by gamma-spectrometry faces the problem of proper natural background subtraction. Background fluctuation can cause differences in activity determination. Also the minimum detectable activity (MDA) of natural and artificial radionuclides can be influenced by background fluctuation. In this paper, results of the background fluctuation of shielded HPGe detectors with relative efficiency of 50-150% are presented together with the assessment of its influence on the determination of natural and artificial radionuclides. © 2013 Elsevier Ltd. All rights reserved.

  17. Thorium determination in intercomparison samples and in some Romanian building materials by gamma ray spectrometry.

    PubMed

    Pantelica, A; Georgescu, I I; Murariu-Magureanu, M D; Margaritescu, I; Cincu, E

    2001-01-01

    Thorium content in zircon sand, thorium ore and a thorium liquid sample (EU Laboratories Network Intercomparison), as well as in some Romanian building materials: sand, wood, tufa, asbestos-cement. cement mill dust, coal fly ash, bricks, and tile (28 samples) was deterimined by gamma ray spectrometry. For the building materials, 226Ra, 40K and 137Cs specific activities were also measured. The results were compared with the Romanian legal norms concerning the highest admissible levels for 232Th, 226Ra. and 40K radioactivity. and to Th, U, and K concentration values previously determined in our laboratory on similar types of samples.

  18. Characterisation of uranium(VI) sorption by two environmental fungal species using gamma spectrometry.

    PubMed

    Gargarello, R; Cavalitto, S; Di Gregorio, D; Niello, J Fernández; Huck, H; Pardo, A; Somacal, H; Curutchet, G

    2008-12-01

    Uranium(VI) sorption by two highly uranium-resistant air-borne fungi in a low-pH medium was measured by means of gamma spectrometry. Growth kinetics and stoichiometry of the two fungal species were also studied. Results show acceptable growth rates in synthetic medium with glucose and ammonia as carbon and nitrogen sources, respectively. Typical oxidative metabolism of carbohydrates was found. In vivo uptake of the radionuclide was negligible, but biosorption dry biomass presented a remarkable performance. The fungal strains showed potential for use in bioremediation.

  19. Nuclear chemistry of returned lunar samples: Nuclide analysis by gamma-ray spectrometry

    NASA Technical Reports Server (NTRS)

    Okelley, G. D.

    1975-01-01

    Primordial and cosmogenic radionuclide concentrations are determined nondestructively by gamma-ray spectrometry in soil and rock samples from the returned Apollo 17 sample collection from Taurus-Littrow and Descartes. Geochemical evidence in support of field geology speculation concerning layering of the subfloor basalt flows is demonstrated along with a possible correlation of magmatic fractionation of K/U as a function of depth. The pattern of radionuclide concentrations observed in these samples is distinct due to proton bombardment by the intense solar flares of August 4-9, 1972. Such radionuclide determinations are used in determining lunar sample orientation and characterizing solar flare activity.

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

    PubMed

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

    2010-07-01

    Radium isotopes are widely used in marine studies (eg. to trace water masses, to quantify mixing processes or to study submarine groundwater discharge). While 228Ra and 226Ra are usually measured using gamma spectrometry, short-lived Ra isotopes (224Ra and 223Ra) 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 226Ra, 228Ra, 224Ra, 223Ra activities measured using low-background gamma spectrometry in standard samples, in water samples collected in the vicinity of our laboratory (La Palme and Vaccarès lagoons, France) but also in seawater samples collected in the plume of the Amazon river, off French Guyana (AMANDES project). The 223Ra and 224Ra 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 224Ra activities are similar for the two techniques. RaDeCC is more sensitive for the detection of low 223Ra activities. Gamma spectrometry thus constitutes an alternate method for the determination of short-lived Ra isotopes. 2009 Elsevier Ltd. All rights reserved.

  1. Measurement of uranium series radionuclides in rock and groundwater at the Koongarra ore deposit, Australia, by gamma spectrometry

    SciTech Connect

    Yanase, Nobuyuki; Sekine, Keiichi

    1995-12-31

    Gamma spectrometry without any self-absorption correction was developed to measure low energy gamma rays emitted by uranium and actinium series radionuclides in rock samples and groundwater residues collected at the Koongarra ore deposit, Australia. Thin samples were prepared to minimize the self-absorption by uranium in the samples. The present method gave standard deviations of 0.9 to 18% for the measurements of concentrations of uranium and actinium series radionuclides. The concentrations of {sup 238}U, {sup 230}Th and {sup 235}U measured by gamma spectrometry were compared with those by alpha spectrometry that requires a complicated chemical separation procedure. The results obtained by both methods were in fairly good agreement, and it was found that the gamma spectrometry is applicable to rock and groundwater samples having uranium content sup to 8.1% (10{sup 3} B1/g) and 3 Bq/l of {sup 238}U, respectively. The detection limits were calculated to be of the order of 10{sup {minus}2} Bq/g for rock samples and 10{sup {minus}1} Bq/l for groundwater samples. The concentrations of uranium and actinium series radionuclides can be determined precisely in these samples using gamma spectrometry without any self-absorption correction.

  2. Total Absorption Gamma-ray Spectrometer (TAGS) Intensity Distributions from INL's Gamma-Ray Spectrometry Center

    DOE Data Explorer

    Greenwood, R. E.

    A 252Cf fission-product source and the INL on-line isotope separator were used to supply isotope-separated fission-product nuclides to a total absorption -ray spectrometer. This spectrometer consisted of a large (25.4-cm diameter x 30.5-cm long) NaI(Tl) detector with a 20.3-cm deep axial well in which is placed a 300-mm2 x 1.0-mm Si detector. The spectra from the NaI(Tl) detector are collected both in the singles mode and in coincidence with the B-events detected in the Si detector. Ideally, this detector would sum all the energy of the B- rays in each cascade following the population of daughter level by B- decay, so that the event could be directly associated with a particular daughter level. However, there are losses of energy from attenuation of the rays before they reach the detector, transmission of rays through the detector, escape of secondary photons from Compton scattering, escape of rays through the detector well, internal conversion, etc., and the measured spectra are thus more complicated than the ideal case and the analysis is more complex. Analysis methods have been developed to simulate all of these processes and thus provide a direct measure of the B- intensity distribution as a function of the excitation energy in the daughter nucleus. These data yield more accurate information on the B- distribution than conventional decay-scheme studies for complex decay schemes with large decay energies, because in the latter there are generally many unobserved and observed but unplaced rays. The TAGS data have been analyzed and published [R. E. Greenwood et al., Nucl Instr. and metho. A390(1997)] for 40 fission product-nuclides to determine the B- intensity distributions. [Copied from the TAGS page at http://www.inl.gov/gammaray/spectrometry/tags.shtml]. Those values are listed on this page for quick reference.

  3. The use of gamma spectrometry in the determination of fission products migration in irradiated fuel

    SciTech Connect

    2015-07-01

    Non destructive examinations realized in hot cells of LECA STAR facility give main data on irradiated fuel rods and pins. Among those examinations, gamma spectrometry allows access to fuel, inside the cladding, thanks to gamma rays of fission products such as {sup 137}Cs, {sup 154}Eu coming from pellets... From those gamma scannings we can detect the position and the length of the fuel column and of its pellets, calculate local burnup.. In the database of our lab we have already such gamma scannings on hundreds of rods or pins with different fuels, claddings and irradiations conditions (under nominal or non nominal). We have detected that in specific cases, an unusual shape of the {sup 137}Cs scanning (distribution quite different from those of {sup 154}Eu) can be explained by the migration of this isotope, moving to the cold sides of the pellet. This phenomenon is mainly associated with an increasing of the pellet's temperature. Based on our observations, we have developed a quantitative approach of the changes on the {sup 137}Cs scannings through the calculation of appropriate 'indicators'. Those calculations allow us to be able to localize, quantify and compare the {sup 137}Cs migration all along rods or pins. Those migration results are so quickly and easily achievable from gamma measurements and can then be easily correlated to other observations realized with destructive examinations, puncturing and calculations, already realized or to come. Because such a migration is the result of temperature increasing in the pellets, our indicators can be directly associated with this local temperature. In perspective, thermically activated phenomena such as geometrical changes in the shape of the pellets, fission gas release... can also indirectly be deduced from our indicators. (authors)

  4. Determination of radionuclide levels in rainwater using ion exchange resin and gamma-spectrometry.

    PubMed

    Jungck, Matthias H A; Andrey, Jean-Louis; Froidevaux, Pascal

    2009-04-01

    The evaluation of radioactivity accidentally released into the atmosphere involves determining the radioactivity levels of rainwater samples. Rainwater scavenges atmospheric airborne radioactivity in such a way that surface contamination can be deduced from rainfall rate and rainwater radioactivity content. For this purpose, rainwater is usually collected in large surface collectors and then measured by gamma-spectrometry after such treatments as evaporation or iron hydroxide precipitation. We found that collectors can be adapted to accept large surface (diameter 47mm) cartridges containing a strongly acidic resin (Dowex AG 88) which is able to quantitatively extract radioactivity from rainwater, even during heavy rainfall. The resin can then be measured by gamma-spectrometry. The detection limit is 0.1Bq per sample of resin (80g) for (137)Cs. Natural (7)Be and (210)Pb can also be measured and the activity ratio of both radionuclides is comparable with those obtained through iron hydroxide precipitation and air filter measurements. Occasionally (22)Na has also been measured above the detection limit. A comparison between the evaporation method and the resin method demonstrated that 2/3 of (7)Be can be lost during the evaporation process. The resin method is simple and highly efficient at extracting radioactivity. Because of these great advantages, we anticipate it could replace former rainwater determination methods. Moreover, it does not necessitate the transportation of large rainwater volumes to the laboratory.

  5. Optimal measurement counting time and statistics in gamma spectrometry analysis: The time balance

    NASA Astrophysics Data System (ADS)

    Joel, Guembou Shouop Cebastien; Penabei, Samafou; Maurice, Ndontchueng Moyo; Gregoire, Chene; Jilbert, Nguelem Mekontso Eric; Didier, Takoukam Serge; Werner, Volker; David, Strivay

    2017-01-01

    The optimal measurement counting time for gamma-ray spectrometry analysis using HPGe detectors was determined in our laboratory by comparing twelve hours measurement counting time at day and twelve hours measurement counting time at night. The day spectrum does not fully cover the night spectrum for the same sample. It is observed that the perturbation come to the sun-light. After several investigations became clearer: to remove all effects of radiation from outside (earth, the sun, and universe) our system, it is necessary to measure the background for 24, 48 or 72 hours. In the same way, the samples have to be measured for 24, 48 or 72 hours to be safe to be purified the measurement (equality of day and night measurement). It is also possible to not use the background of the winter in summer. Depend on to the energy of radionuclide we seek, it is clear that the most important steps of a gamma spectrometry measurement are the preparation of the sample and the calibration of the detector.

  6. Rapid determination of (237)Np in soil samples by multi-collector inductively-coupled plasma mass spectrometry and gamma spectrometry.

    PubMed

    Yi, Xiaowei; Shi, Yanmei; Xu, Jiang; He, Xiaobing; Zhang, Haitao; Lin, Jianfeng

    A radiochemical procedure is developed for the determination of (237)Np in soil with multi-collector inductively-coupled plasma mass spectrometry (MC-ICP-MS) and gamma-spectrometry. (239)Np (milked from (243)Am) was used as an isotopic tracer for chemical yield determination. The neptunium in the soil is separated by thenoyl-trifluoracetone extraction from 1 M HNO3 solution after reducing Np to Np(IV) with ferrous sulfamate, and then purified with Dowex 1 × 2 anion exchange resin. (239)Np in the resulting solution is measured with gamma-spectrometry for chemical yield determination while the (237)Np is measured with MC-ICP-MS. Measurement results for soil samples are presented together with those for two reference samples. By comparing the determined value with the reference value of the (237)Np activity concentration, the feasibility of the procedure was validated.

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

    SciTech Connect

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

    2014-09-03

    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 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 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 spectrometry burnup evaluations and the expected burnup from simulation. For all four compacts analyzed by mass spectrometry, the maximum range in the three experimentally determined values and the predicted value was 6% or less. Furthermore, the results confirm the accuracy of the nondestructive burnup evaluation from gamma spectrometry

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

    DOE PAGES

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

    2014-09-03

    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 methodsmore » 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 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 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 spectrometry burnup evaluations and the expected burnup from simulation. For all four compacts analyzed by mass spectrometry, the maximum range in the three experimentally determined values and the predicted value was 6% or less. Furthermore, the results confirm the accuracy of the nondestructive burnup evaluation from gamma

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

    NASA Astrophysics Data System (ADS)

    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.

  10. The 124Sb activity standardization by gamma spectrometry for medical applications

    NASA Astrophysics Data System (ADS)

    de Almeida, M. C. M.; Iwahara, A.; Delgado, J. U.; Poledna, R.; da Silva, R. L.

    2010-07-01

    This work describes a metrological activity determination of 124Sb, 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. 124Sb is also applied in animal organ distribution studies to solve some questions in pharmacology. 124Sb decays by β-emission and it produces several photons (X and gamma rays) with energy varying from 27 to 2700 keV. Efficiency curves to measure point 124Sb solid sources were obtained from a 166mHo 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 124Sb 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.

  11. NMIS with Imaging and Gamma Ray Spectrometry for Pu, HEU, HE and Other Materials

    SciTech Connect

    Mihalczo, John T; Mullens, James Allen

    2012-03-01

    The Nuclear Material Identification System (NMIS) has been under development at ORNL and the National Nuclear Security Administration (NNSA) Y-12 National Security Complex since 1984. In the mid-1990s, what is now the US Department of Energy (DOE) Office of Nuclear Verification (ONV) realized that it was a useful technology for future arms control treaty applications and supported further development of the system. In 2004, fast-neutron imaging was incorporated into the system. In 2007, the ONV decided to develop a fieldable version of the system, designated as FNMIS, for potential use in future treaties. The FNMIS is being developed to be compatible with the eventual incorporation of gamma-ray spectrometry and an information barrier. This report addresses how and what attributes could be determined by the FNMIS system with gamma-ray spectrometry. The NMIS is a time-dependent coincidence system that incorporates tomographic imaging (including mapping of the fission sites) and gamma-ray spectrometry. It utilizes a small, lightweight (30 lb), portable deuterium-tritium (DT) neutron (14.1 MeV) generator (4 x 10{sup 7} neutrons/second) for active interrogation and can also perform passive interrogation. A high-purity germanium (HPGe) gamma-ray detector with multichannel analysis can be utilized in conjunction with the source for active interrogation or passively. The system uses proton recoil scintillators: 32 small 2.5 x 2.5 x 10.2-cm-thick plastic scintillators for imaging and at least two 2 x 2 arrays of 27 x 27 x 10-cm-thick plastic scintillators that detect induced fission radiation. The DT generator contains an alpha detector that time and directionally tags a fan beam of some of the neutrons emitted and subdivides it into pixels. A fast (1 GHz) time correlation processor measures the time-dependent coincidence among all detectors in the system. A computer-controlled scanner moves the small detectors and the source appropriately for scanning a target object for

  12. Analysis of spectra from portable handheld gamma-ray spectrometry for terrain comparative assessment.

    PubMed

    Dias, Flávio; Lima, Marco; Sanjurjo-Sánchez, Jorge; Alves, Carlos

    2016-04-01

    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). Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Fission Product Inventory and Burnup Evaluation of the AGR-2 Irradiation by Gamma Spectrometry

    SciTech Connect

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

    2016-11-01

    Gamma spectrometry has been used to evaluate the burnup and fission product inventory of different components from the US Advanced Gas Reactor Fuel Development and Qualification Program's second TRISO-coated particle fuel irradiation test (AGR-2). TRISO fuel in this irradiation included both uranium carbide / uranium oxide (UCO) kernels and uranium oxide (UO2) kernels. Four of the 6 capsules contained fuel from the US Advanced Gas Reactor program, and only those capsules will be discussed in this work. The inventories of gamma-emitting fission products from the fuel compacts, graphite compact holders, graphite spacers and test capsule shell were evaluated. These data were used to measure the fractional release of fission products such as Cs-137, Cs-134, Eu-154, Ce-144, and Ag-110m from the compacts. The fraction of Ag-110m retained in the compacts ranged from 1.8% to full retention. Additionally, the activities of the radioactive cesium isotopes (Cs-134 and Cs-137) have been used to evaluate the burnup of all US TRISO fuel compacts in the irradiation. The experimental burnup evaluations compare favorably with burnups predicted from physics simulations. Predicted burnups for UCO compacts range from 7.26 to 13.15 % fission per initial metal atom (FIMA) and 9.01 to 10.69 % FIMA for UO2 compacts. Measured burnup ranged from 7.3 to 13.1 % FIMA for UCO compacts and 8.5 to 10.6 % FIMA for UO2 compacts. Results from gamma emission computed tomography performed on compacts and graphite holders that reveal the distribution of different fission products in a component will also be discussed. Gamma tomography of graphite holders was also used to locate the position of TRISO fuel particles suspected of having silicon carbide layer failures that lead to in-pile cesium release.

  14. Fission Product Inventory and Burnup Evaluation of the AGR-2 Irradiation by Gamma Spectrometry

    SciTech Connect

    Harp, Jason Michael; Stempien, John Dennis; Demkowicz, Paul Andrew

    2016-09-01

    Gamma spectrometry has been used to evaluate the burnup and fission product inventory of different components from the US Advanced Gas Reactor Fuel Development and Qualification Program's second TRISO-coated particle fuel irradiation test (AGR-2). TRISO fuel in this irradiation included both uranium carbide / uranium oxide (UCO) kernels and uranium oxide (UO2) kernels. Four of the 6 capsules contained fuel from the US Advanced Gas Reactor program, and only those capsules will be discussed in this work. The inventories of gamma-emitting fission products from the fuel compacts, graphite compact holders, graphite spacers and test capsule shell were evaluated. These data were used to measure the fractional release of fission products such as Cs-137, Cs-134, Eu-154, Ce-144, and Ag-110m from the compacts. The fraction of Ag-110m retained in the compacts ranged from 1.8% to full retention. Additionally, the activities of the radioactive cesium isotopes (Cs-134 and Cs-137) have been used to evaluate the burnup of all US TRISO fuel compacts in the irradiation. The experimental burnup evaluations compare favorably with burnups predicted from physics simulations. Predicted burnups for UCO compacts range from 7.26 to 13.15 % fission per initial metal atom (FIMA) and 9.01 to 10.69 % FIMA for UO2 compacts. Measured burnup ranged from 7.3 to 13.1 % FIMA for UCO compacts and 8.5 to 10.6 % FIMA for UO2 compacts. Results from gamma emission computed tomography performed on compacts and graphite holders that reveal the distribution of different fission products in a component will also be discussed. Gamma tomography of graphite holders was also used to locate the position of TRISO fuel particles suspected of having silicon carbide layer failures that lead to in-pile cesium release.

  15. Waste Characterization Using Gamma Ray Spectrometry with Automated Efficiency Optimization - 13404

    SciTech Connect

    Bosko, A.; Venkataraman, R.; Bronson, F.L.; Ilie, G.; Russ, W.R.

    2013-07-01

    Gamma ray spectrometry using High Purity Germanium (HPGe) detectors is commonly employed in assaying radioactive waste streams from a variety of sources: nuclear power plants, Department of Energy (DOE) laboratories, medical facilities, decontamination and decommissioning activities etc. The radioactive material is typically packaged in boxes or drums (for e.g. B-25 boxes or 208 liter drums) and assayed to identify and quantify radionuclides. Depending on the origin of the waste stream, the radionuclides could be special nuclear materials (SNM), fission products, or activation products. Efficiency calibration of the measurement geometry is a critical step in the achieving accurate quantification of radionuclide content. Due to the large size of the waste items, it is impractical and expensive to manufacture gamma ray standard sources for performing a measurement based calibration. For well over a decade, mathematical efficiency methods such as those in Canberra's In Situ Object Counting System (ISOCS) have been successfully employed in the efficiency calibration of gamma based waste assay systems. In the traditional ISOCS based calibrations, the user provides input data such as the dimensions of the waste item, the average density and fill height of the matrix, and matrix composition. As in measurement based calibrations, the user typically defines a homogeneous matrix with a uniform distribution of radioactivity. Actual waste containers can be quite nonuniform, however. Such simplifying assumptions in the efficiency calibration could lead to a large Total Measurement Uncertainty (TMU), thus limiting the amount of waste that can be disposed of as intermediate or low activity level waste. To improve the accuracy of radionuclide quantification, and reduce the TMU, Canberra has developed the capability to optimize the efficiency calibration using the ISOCS method. The optimization is based on benchmarking the efficiency shape and magnitude to the data available in the

  16. Recent developments in ultra low-level gamma-ray spectrometry at IRMM

    PubMed

    Hult; Martinez Canet MJ; Kohler; das Neves J; Johnston

    2000-07-01

    IRMM performs ultra low-level gamma-ray spectrometry in the underground laboratory HADES, located at the SCK-CEN site in Mol, Belgium. Recently a third low-background coaxial HPGe detector was put into operation. The detector has 60% relative efficiency and better background characteristics than the two previous detectors: The shield comprises 14 cm of lead with 21OPb specific activity of 20 Bq kg(-1) and 14 cm of freshly produced electrolytic copper. The background count rate integrated from 40 to 2700 keV is 394 +/- 2 counts per day. Details of the background and the shield are presented together with applications to nuclear safeguards and material selection.

  17. Gamma-ray spectrometry in the cascade area of a gas centrifuge enrichment plant

    SciTech Connect

    Lauppe, W.D.; Richter, B.; Stein, G.

    1985-01-01

    In the frame of the programme of the Federal Republic of Germany in support of the IAEA, measurements were performed in the SP4 gas centrifuge enrichment plant in Almelo, the Netherlands. The objective was the investigation of the applicability of non-destructive ..gamma..-spectrometry equipment - presently available to the IAEA - at uranium-hexafluoride cascade piping for the purpose of measuring the uranium enrichment. The measurement locations were chosen at the product pipework between the top of a cascade and the first valve, which is inside the cascade area. Taking account of the results of the Hexapartite Safeguards Project, the measurement method should be capable of giving a go/no go result on current and preceding production of high-enriched uranium. The paper gives a description of the acquired measurement method and evaluation. The measurement results are discussed and conclusions are drawn.

  18. A review of the nationwide proficiency test on natural radioactivity measurements by gamma spectrometry.

    PubMed

    Şahin, N K; Yeltepe, E; Yücel, Ü

    2016-03-01

    This study is the review of the first proficiency test on radioactivity measurement organized in Turkey by Sarayköy Nuclear Research and Training Center (SANAEM) of Turkish Atomic Energy Authority (TAEK) in 2013. The objective of the test was to determine (226)Ra, (232)Th and (40)K activity concentrations in natural soil samples using gamma-ray spectrometry. The bulk material consisting of uranium- and thorium-rich soil and sand was milled, mixed thoroughly and sieved. Homogeneity of the final mix was tested with 6 randomly taken samples. 16 proficiency test samples were distributed to 16 participating laboratories. 12 laboratories reported results. The results were evaluated on the accuracy and precision criteria adopted by the IAEA Proficiency Testing Group. The percentage of acceptable scores was 49%. Some recommendations have been provided to the laboratories to improve the quality of their results. It is planned to extend these proficiency tests periodically for various radionuclides in various matrices.

  19. Summary of gamma spectrometry on local air samples from 1985--1995

    SciTech Connect

    Winn, W.G.

    1997-04-02

    This report summarizes the 1985--1995 results of low-level HPGe gamma spectrometry analysis of high-volume air samples collected at the Aiken Airport, which is about 25 miles north of SRS. The author began analyzing these samples with new calibrations using the newly developed GRABGAM code in 1985. The air sample collections were terminated in 1995, as the facilities at the Aiken Airport were no longer available. Air sample measurements prior to 1985 were conducted with a different analysis system (and by others prior to 1984), and the data were not readily available. The report serves to closeout this phase of local NTS air sample studies, while documenting the capabilities and accomplishments. Hopefully, the information will guide other applications for this technology, both locally and elsewhere.

  20. Semi-automated structural analysis of high resolution magnetic and gamma-ray spectrometry airborne surveys

    NASA Astrophysics Data System (ADS)

    Debeglia, N.; Martelet, G.; Perrin, J.; Truffert, C.; Ledru, P.; Tourlière, B.

    2005-08-01

    A user-controlled procedure was implemented for the structural analysis of geophysical maps. Local edge segments are first extracted using a suitable edge detector function, then linked into straight discontinuities and, finally, organised in complex boundary lines best delineating geophysical features. Final boundary lines may be attributed by a geologist to lithological contacts and/or structural geological features. Tests of some edge detectors, (i) horizontal gradient magnitude (HGM), (ii) various orders of the analytic signal ( An), reduced to the pole or not, (iii) enhanced horizontal derivative (EHD), (iv) composite analytic signal (CAS), were performed on synthetic magnetic data (with and without noise). As a result of these comparisons, the horizontal gradient appears to remain the best operator for the analysis of magnetic data. Computation of gradients in the frequency domain, including filtering and upward continuation of noisy data, is well-suited to the extraction of magnetic gradients associated to deep sources, while space-domain smoothing and differentiation techniques is generally preferable in the case of shallow magnetic sources, or for gamma-ray spectrometry analysis. Algorithms for edge extraction, segment linking, and line following can be controlled by choosing adequate edge detector and processing parameters which allows adaptation to a desired scale of interpretation. Tests on synthetic and real case data demonstrate the adaptability of the procedure and its ability to produce basic layer for multi-data analysis. The method was applied to the interpretation of high-resolution airborne magnetic and gamma-ray spectrometry data collected in northern Namibia. It allowed the delineation of dyke networks concealed by superficial weathering and demonstrated the presence of lithological variations in alluvial flows. The output from the structural analysis procedure are compatible with standard GIS softwares and enable the geologist to (i) compare

  1. Investigation of the soil-plant transfer of primordial radionuclides in tomatoes by low-level gamma-ray spectrometry.

    PubMed

    Köhler, M; Gleisberg, B; Niese, S

    2000-01-01

    The paper presents actual data from investigations of the soil-plant transfer of the primordial radionuclides 40K, 238U, 226Ra, 210Pb and 227Ac for tomatoes growing at soils from former uranium mining areas. The analysis were carried out using low-level gamma-ray spectrometry in a 47 m deep underground laboratory. For tomato fruits transfer factors of (0.0007 +/- 0.0006) for 235U, (0.0021 +/- 0.0017) for 226Ra, (0.0015 +/- 0.0009) for 210Pb and (0.0018 +/- 0.0012) for 227Ac were obtained. The investigation of the soil-plant transfer by low-level gamma-ray spectrometry is often limited by the Compton-continuum from the always present high-energy gamma-ray emitter 40K.

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

    SciTech Connect

    Gregorich, Carola

    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. Application of gamma-ray spectrometry in a NORM industry for its radiometrical characterization

    NASA Astrophysics Data System (ADS)

    Mantero, J.; Gázquez, M. J.; Hurtado, S.; Bolívar, J. P.; García-Tenorio, R.

    2015-11-01

    Industrial activities involving Naturally Occurring Radioactive Materials (NORM) are found among the most important industrial sectors worldwide as oil/gas facilities, metal production, phosphate Industry, zircon treatment, etc. being really significant the radioactive characterization of the materials involved in their production processes in order to assess the potential radiological risk for workers or natural environment. High resolution gamma spectrometry is a versatile non-destructive radiometric technique that makes simultaneous determination of several radionuclides possible with little sample preparation. However NORM samples cover a wide variety of densities and composition, as opposed to the standards used in gamma efficiency calibration, which are either water-based solutions or standard/reference sources of similar composition. For that reason self-absorption correction effects (especially in the low energy range) must be considered individually in every sample. In this work an experimental and a semi-empirical methodology of self-absorption correction were applied to NORM samples, and the obtained results compared critically, in order to establish the best practice in relation to the circumstances of an individual laboratory. This methodology was applied in samples coming from a TiO2 factory (NORM industry) located in the south-west of Spain where activity concentration of several radionuclides from the Uranium and Thorium series through the production process was measured. These results will be shown in this work.

  4. An airborne gamma-ray spectrometry survey of nuclear sites in Belgium.

    PubMed

    Sanderson, D C W; Cresswell, A J; Hardeman, F; Debauche, A

    2004-01-01

    As part of a wider study to define the existing background levels in Belgium an airborne gamma-ray survey was conducted in two areas associated with nuclear sites. In the Mol area, the survey zone included areas surrounding the SCK-CEN nuclear research centre, and its associated neighbourhood which includes radioactive waste stores, fuel manufacture and fabrication facilities and an international accelerator laboratory. In the vicinity of Fleurus, the survey included the IRE complex with radiochemical laboratories, irradiation facilities and stores, and isotope production accelerators. The survey was conducted using a twin engined helicopter equipped with a combined scintillation and semiconductor spectrometer. The system was installed and tested in the UK, and then transferred to Belgium for operations. The complete survey was conducted successfully within 1 week. The results provide a comprehensive record of the radiation environment of the nuclear sites at time of survey, and show a range of signals associated with the types of activity present in each area. They confirm that radiation fields are largely confined to the operational sites, and provide a traceable record against which future changes could be assessed. The demonstration of efficient deployment between two European countries, coupled with rapid mapping of many different radiometric signals around these sites confirms the utility of the airborne gamma spectrometry approach for accurate definition of enhanced radiation fields. This has important implications for emergency response.

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

    NASA Astrophysics Data System (ADS)

    Makmal, T.; Aviv, O.; Gilad, E.

    2016-10-01

    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.

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

    PubMed

    Chagren, S; Ben Tekaya, M; 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.

  7. Gamma-ray spectrometry data collection and reduction by simple computing systems.

    PubMed

    Op de Beeck, J

    1975-12-01

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

  9. On-line interrogation of pebble bed reactor fuel using passive gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    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

  10. Uncertainty of gamma-ray spectrometry measurement of environmental samples due to uncertainties in matrix composition, density and sample geometry.

    PubMed

    Kaminski, S; Jakobi, A; Wilhelm, Chr

    2014-12-01

    This paper is intended to identify the uncertainties of activities in environmental samples measured with gamma-ray spectrometry that result from uncertainties in matrix composition, density and geometrical dimensions of the sample. For that purpose efficiencies were calculated for a wide range of environmental matrices such as fresh and ashed food samples, water samples and soil samples. Compositions were mainly taken from literature. Densities and geometry parameters were varied in a range occurring in practice. Considered energies cover a range from 46.5keV to 2000keV. Finally, a couple of recommendations in respect to gamma-ray spectrometric measurements of environmental samples are given.

  11. Application of low-background gamma-ray spectrometry to monitor radioactivity in the environment and food.

    PubMed

    Khan, A J; Semkow, T M; Beach, S E; Haines, D K; Bradt, C J; Bari, A; Syed, U-F; Torres, M; Marrantino, J; Kitto, M E; Menia, T; Fielman, E

    2014-08-01

    The results are described of an upgrade of the low-background gamma-ray spectrometry laboratory at New York State Department of Health by acquiring sensitivity to low-energy gamma rays. Tuning of the spectrometer and its low-energy response characteristics are described. The spectrometer has been applied to monitor the environment by measuring aerosols and water in New York State contaminated by the 2011 Fukushima accident plume. In addition, the spectrometer has been used to monitor radioactivity in food by performing a study of cesium in Florida milk.

  12. Gamma-ray spectrometry across the Aalenian-Bajocian boundary in the Lusitanian Basin (Western Portugal)

    NASA Astrophysics Data System (ADS)

    Santos, Marisa; Henriques, Helena; Pena, Rui

    2016-04-01

    supply, which has enabled the faunal recovery, as well as the raise of deep infaunal foraminifers recorded at the latest part of the Discites Biochron. This could be related to the increase of calcareous nannofossil fluxes that coincide with a positive shift in carbon isotope compositions of bulk carbonate in the earliest Bajocian reported by some authors for the Murtinheira and other Iberian sections. In basin analysis of carbonate platforms the integration of major biotic turnovers and gamma-ray spectrometry data can be a useful tool in the improvement of correlation between wells and outcrops. Moreover, they assist in the interpretation of depositional environment and paleoclimatic constrains assigned to a basin.

  13. Analysis by gas chromatography-mass spectrometry of the essential oil from the aerial parts of Pimpinella junoniae Ceb. & Ort., gathered in La Gomera, Canary Islands, Spain.

    PubMed

    Velasco-Negueruela, A; Pérez-Alonso, M J; Pérez de Paz, P L; Paúl-Palá, J; Sanz, J

    2003-09-05

    The essential oil from the aerial parts of Pimpinella junoniae Ceb. & Ort., growing in La Gomera, Canary Islands, Spain, was studied by gas chromatography and gas chromatography-mass spectrometry, and 43 constituents were identified. The major components were found to be alpha-zingiberene (20.6%), alpha-pinene (17.9%), (E)-beta-farnesene (9.3%), ar-curcumene (7.4%), beta-phellandrene (7.0%), beta-bisabolene (6.1%) and epoxypseudoisoeugenyl 2-methylbutyrate (6.0%). The decomposition product of epoxypseudoisoeugenol derivatives, 5-methoxy-2-methylbenzofuran (5.7%), moderate amounts of other arylpropanoids with the pseudoisoeugenol skeleton (total percentage, 5.2%) and other compounds such as beta-sesquiphellandrene (3.0%), cis-beta-guaiene (1.5%), alpha-phellandrene (1.5%) and alpha-bisabolol (1.3%), were also found.

  14. 137Cs measurement uncertainties and detection limits for airborne gamma spectrometry (AGS) data analysed using a spectral windows method.

    PubMed

    Cresswell, A J; Sanderson, D C W; White, D C

    2006-02-01

    The uncertainties associated with airborne gamma spectrometry (AGS) measurements analysed using a spectral windows method, and associated detection limits, have been investigated. For individual short measurements over buried 137Cs activity detection limits of 10 kBq m(-2) are achieved. These detection limits are reduced for superficial activity and longer integration times. For superficial activity, detection limits below 1 kBq m(-2) are achievable. A comparison is made with the detection limits for other data processing methods.

  15. Comparison of airborne and terrestrial gamma spectrometry measurements - evaluation of three areas in southern Sweden.

    PubMed

    Kock, Peder; Samuelsson, Christer

    2011-06-01

    The Geological Survey of Sweden (SGU) has been conducting airborne gamma spectrometry measurements of natural radioactivity in Sweden for more than 40 years. Today, the database covers about 80% of the country's land surface. This article explores the first step of putting this data into use in radioactive source search at ground level. However, in order to be able to use the airborne background measurements at ground level, SGU data must be validated against terrestrial data. In this work, we compare the SGU data with data measured by a portable backpack system. This is done for three different areas in southern Sweden. The statistical analysis shows that a linear relationship and a positive correlation exist between the air and ground data. However, this linear relationship could be revealed only when the region possessed large enough variations in areal activity. Furthermore, the activity distributions measured show good agreement to those of SGU. We conclude that the SGU database could be used for terrestrial background assessment, given that a linear transfer function is established.

  16. Detection of /sup 210/Pb in the lungs of smokers by in-vivo gamma spectrometry

    SciTech Connect

    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.

  17. Low-background gamma-ray spectrometry in the Garching underground laboratory

    NASA Astrophysics Data System (ADS)

    Hofmann, M.; Mannel, T.; Sivers, M. V.

    2013-08-01

    We describe two setups that were built for low-background gamma-ray spectrometry in the Garching Underground Laboratory (˜ 10 m.w.e.). Both setups are based on HPGe detectors surrounded by several layers of passive shielding as well as an active muon veto. The first setup (GEM) comprises a single HPGe detector surrounded by a NaI(Tl) scintillation detector that serves as anti-Compton veto. The second setup (LoAx) consists of two smaller HPGe detectors which are arranged face-to-face to cover a large solid angle around the sample. The detection efficiency of both systems is determined using a calibrated Monte-Carlo simulation. The count rate finally achieved in the energy range 40-2700keV is 10250±26cts/day for the GEM setup, and 5258±27cts/day and 6876±31cts/day between 20-1500keV for the two detectors of the LoAx setup. This leads to detection sensitivities of a few mBq/kg for U and Th at both screening stations.

  18. Rapid measurements of concentrations of natural uranium in process stream samples via gamma spectrometry at an extraction facility.

    PubMed

    Sundar, Uma; Ramamurthy, Vasantha; Buche, Vinay; Rao, D Narasinga; Sivadasan, P C; Yadav, R B

    2007-09-30

    A new application of gamma spectrometry in the efficient measurement of natural uranium in the process stream at an extraction plant is described here. The inherent nuclear properties of uranium viz. emanation of characteristic gamma rays (185.7keV) has been exploited for the determination of concentrations ranging from 5 to 450gl(-1) by passive photon counting of 185.7keV gamma rays from (235)U isotope for a maximum of 3-10min per sample. This technique is totally matrix independent unlike other instrumental analytical techniques like wavelength dispersive X-ray fluorescence spectrometry and UV-vis spectrophotometry. Solution samples of aqueous and organic phase can be directly counted without the requirement of sample preparation. A MINIM-based gamma spectrometer consisting of a multichannel pulse height analyzer and a 3in.x3in. well-type NaI(Tl) scintillation detector with an approximately 2in. thick lead shield has been employed for the measurements. The results are compared with those obtained by potentiometry and wavelength dispersive X-ray fluorescence spectrometry (WD-XRF). Relative standard deviation of 1-5% has been obtained depending upon the concentration of uranium, which is more than adequate for routine process control samples. This paper also discusses in detail the problems associated with the determination of high concentrations of uranium in using 63 and 93keV gamma rays emanating from (234)Th (t(1/2) 24 days) the immediate daughter of (238)U isotope in samples that have attained secular equilibrium and the limitations of these energies in the routine analysis of freshly extracted uranium.

  19. A NEW METHDOLOGY FOR DETERMINING FISSILE MASS IN INDIVIDUAL ACCOUNTING ITEMS WITH THE USE OF GAMMA-RAY SPECTROMETRY.

    SciTech Connect

    KANE,W.R.; VANIER,P.E.; ZUHOSKI,P.B.; LEMLEY,J.R.

    2000-07-16

    In the safeguards, arms control, and nonproliferation regimes measurements are required which give the quantity of fissile material in an accounting item, e.g., a standard container of plutonium or uranium oxide. Because of the complexity of modeling the absorption of gamma rays in high-Z materials, gamma-ray spectrometry is not customarily used for this purpose. Gamma-ray measurements can be used to determine the fissile mass when two conditions are met: (1) The material is in a standard container, and (2) The material is finely divided, or a solid item with a reproducible shape. The methodology consists of: (A) Measurement of the emitted gamma rays, and (B) Measurement of the transmission through the item of the high-energy gamma rays of Co-60 and Th-228. We have demonstrated that items containing nuclear materials possess a characteristic ''fingerprint'' of gamma rays which depends not only on the nuclear properties, but also on the mass, density, shape, etc.. The material's spectrum confirms its integrity, homogeneity, and volume as well. While there is attenuation of radiation from the interior, the residual radiation confirms the homogeneity of the material throughout the volume. Transmission measurements, where the attenuation depends almost entirely on Compton scattering, determine the material mass. With well-characterized standards, this methodology can provide an accurate measure of the contained fissile material.

  20. Quantification of endogenous alpha- and gamma-endorphins in rat brain by liquid chromatography-tandem mass spectrometry.

    PubMed

    Kosanam, Hari; Ramagiri, Suma; Dass, Chhabil

    2009-09-01

    Quantification of alpha- and gamma-endorphins in rat brain using liquid chromatography-electrospray ionization-tandem mass spectrometry is described. [D-Ala(2)]-gamma-endorphin is used as an internal standard. The precursor-to-product ion MRM transitions for alpha-endorphin, gamma-endorphin, and [D-Ala(2)]-gamma-endorphin were m/z 873.6-->429.6; 929.6-->542.3; 936.6-->542.3, respectively. The method was validated in terms of linearity, specificity, sensitivity, recovery, precision, and accuracy. The assay was linear over a concentration range of 0.1-200 ng/mL with the limit-of-detection of 0.03 ng/mL and limit-of-quantification of 0.1 ng/mL. The endogenous concentrations of alpha- and gamma-endorphins in rat brains were 13.8+/-0.57 (mean+/-SD; n=5) and 2.5+/-0.43 ng/g of wet tissue weight, respectively.

  1. Neanderthal skeleton from Tabun: U-series data by gamma-ray spectrometry.

    PubMed

    Schwarcz, H P; Simpson, J J; Stringer, C B

    1998-12-01

    The Neanderthal hominid Tabun C1, found in Israel by Garrod & Bate, was attributed to either layer B or C of their stratigraphic sequence. We have used gamma-ray spectrometry to determine the 230Th/234U and 231Pa/235U ratios of two bones from this skeleton, the mandible and a femur. The ages calculated from these ratios depend on the uranium uptake history of the bones. Assuming a model of early U (EU) uptake the age of the Tabun C1 mandible is 34+/-5 ka. The EU age of the femur is 19+/-2 ka. The femur may have experienced continuous (linear) U uptake which would give an age of 33+/-4 ka, in agreement with the mandible's EU age, but implies marked inhomogeneity in U uptake history at the site. These new age estimates for the skeleton suggest that it was younger than deposits of layer C. This apparent age is less than those of other Neanderthals found in Israel, and distinctly younger than the ages of the Skhul and Qafzeh burials. This suggests that Neanderthals did not necessarily coexist with the earliest modern humans in the region. All of the more complete Neanderthal fossils from Israel are now dated to the cool period of the last glacial cycle, suggesting that Neanderthals may have arrived in this region as a result of the southward expansion of their habitable range. The young age determined for the Tabun skeleton would suggest that Neanderthals survived as late in the Levant as they did in Europe.

  2. Car-borne gamma spectrometry: a virtual exercise in emergency response.

    PubMed

    Dowdall, M; Smethurst, M A; Watson, R; Mauring, A; Aage, H K; Andersson, K G; Pálsson, S E

    2012-05-01

    In recent years car-borne gamma spectrometry has expanded from its role as a geological survey platform to being a useful asset in searching for orphan sources and for surveying in the aftermath of an incident involving the release of radioactive materials. The opportunities for gaining practical experience in the field however are limited by cost considerations and practicability. These limitations are exacerbated by the fact that field data can differ significantly from data generated in the laboratory. As a means of exercising existing emergency measuring/surveying capability and introducing car-borne measurements to a larger group, a virtual exercise was devised. The exercise ORPEX (Orphan Sources and Fresh Fallout Virtual Exercise in Mobile Measurement) featured two typical emergency scenarios: a search for orphan sources and surveying to delineate fallout from a local release point. Synthetic spectral data were generated for point sources and inserted into genuine car-borne measurement data. Participants were presented with a typical software tool and data and were asked to report source locations and isotopes within a time limit. In the second scenario, synthetic data representing fallout from a local fire involving radioactive material were added to real car-borne data, participants being asked to produce maps identifying and characterising the regions of contamination. Fourteen individual organisations from seven different countries supplied results which indicated that for strong sources of isotopes with simple spectra featuring high energy peaks, location and identification was not a problem. Problems arose for isotopes with low energy signals or that presented a weak signal even when visible for extended periods. Experienced analysts tended to perform better in identification of sources irrespective of experience with mobile measurements whereas those with experience in such measurements were more confident in providing more precise estimates of

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

    PubMed

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

    2017-02-01

    A new portable sampling system was developed to extract Radium isotopes from large volumes (up to 300L) of fresh surface- and ground-waters of low Ra-activities (<5mBq/L). Ra is quantitatively adsorbed on a small amount (6.5g) of MnO2-coated acrylic fibers, which are then dried and burned at 600°C in the laboratory. The resulting Mn-oxide powder (about 2cm(3) when compacted) is then analyzed through gamma-ray spectrometry which allows measurement of the whole Ra quartet ((226)Ra, (228)Ra, (224)Ra and (223)Ra) in a single counting of a few days. The usual relative standard combined uncertainties (1σ) are 2-3% for (226)Ra, (228)Ra and (224)Ra; and less than 10% for (223)Ra. 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 (226)Ra activities (1-4mBq/L) in both cases, regardless of the contrasted geology (Mesozoic limestone vs crystalline Variscan basement), but clearly distinct ((228)Ra/(226)Ra) ratios in agreement with the differences in Th/U ratios of the two drained areas. Short-lived Ra isotopes ((224)Ra and (223)Ra) appear to be mainly influenced by near-surface desorption/recoil processes for most of the sampling sites. Copyright © 2016. Published by Elsevier Ltd.

  4. Accurate gamma-ray spectrometry measurements of the half-life of 92Sr.

    PubMed

    Leconte, P; Hudelot, J P; Antony, M

    2008-10-01

    Studies of the nuclear fuel cycle require an accurate knowledge of the energy release from the decay of radioactive nuclides produced in a reactor, including precise half-life data for the short-lived radionuclides. Moreover, short-lived fission products are crucial for fission rate distribution measurements performed in low-power facilities, such as EOLE and MINERVE of CEA Cadarache [Fougeras, P., 2005. EOLE, MINERVE and MASURCA facilities and their associated neutron experimental programs. In: 13th International Conference on Nuclear Engineering, Beijing, China, 16-20 May 2005], and their nuclear decay data need to be known to high precision. For these reasons, the half-life of (92)Sr has been measured to solve a recently observed inconsistency identified with the quoted value in the main nuclear applications libraries (including JEFF3.1): T(1/2)=2.71+/-0.01 h [Parsa, B., Ashari, A., Goolvard, L., Nobar, Y.M., 1971. Decay scheme of 2.71 h (92)Sr. Nucl. Phys. A 175, 629-640]. An overestimation of 4.5% has been identified in this work, based on two independent methods. Specific gamma-ray spectrometry measurements on activated fissile foils have been carried out, using two HPGe detectors. Influencing factors such as net area measurements of photopeaks, pulse pile-up accuracy and dead time corrections in the presence of decaying activity are discussed. A new value has been obtained by combining eight series of measurements: T(1/2)=2.594+/-0.006 h. The uncertainty has been reduced by a factor of two with respect to previous evaluations. This measured value also shows good agreement with the most recent studies of T(1/2)=2.627+/-0.009 h [Nir-El, Y., 2003. Private Communications. Soreq Research Centre, Yavne, Israel].

  5. Methylation of gamma-carboxylated Glu (Gla) allows detection by liquid chromatography-mass spectrometry and the identification of Gla residues in the gamma-glutamyl carboxylase

    PubMed Central

    Hallgren, K. W.; Zhang, D.; Kinter, M.; Willard, B.; Berkner, K. L.

    2013-01-01

    Gamma-carboxylated Glu (Gla) is a post-translational modification required for the activity of vitamin K-dependent (VKD) proteins that has been difficult to study by mass spectrometry due to the properties of this negatively-charged residue. Gla is generated by a single enzyme, the gamma-glutamyl carboxylase, which has broad biological impact because VKD proteins have diverse functions that include hemostasis, apoptosis, and growth control. The carboxylase also contains Glas, of unknown function, and is an integral membrane protein with poor sequence coverage. To locate these Glas, we first established methods that resulted in high coverage (92%) of uncarboxylated carboxylase. Subsequent analysis of carboxylated carboxylase identified a Gla-peptide (729-758) and a missing region (625-647) that was detected in uncarboxylated carboxylase. We therefore developed an approach to methylate Gla, which efficiently neutralized Gla and improved mass spectrometric analysis. Methylation eliminated CO2 loss from Gla, increased the ionization of Gla-containing peptide, and appeared to facilitate trypsin digestion. Methylation of a carboxylated carboxylase tryptic digest identified Glas in the 625-647 peptide. These studies provide valuable information for testing the function of carboxylase carboxylation. The methylation approach for studying Gla by mass spectrometry is an important advance that will be broadly applicable to analyzing other VKD proteins. PMID:22536908

  6. (239)Pu, (240)Pu, and (241)Am determination in hot particles by low level gamma-spectrometry.

    PubMed

    Jiménez-Ramos, M C; Hurtado, S; Chamizo, E; García-Tenorio, R; León-Vintró, L; Mitchell, P I

    2010-06-01

    A nondestructive method based on low-energy, high-resolution photon spectrometry is presented which allows accurate determination of (239)Pu, (240)Pu, and (241)Am (as a daughter of (241)Pu) activities in radioactive particles containing relatively high levels of plutonium isotopes. The proposed method requires only one measurement for the establishment of an absolute efficiency curve. Since the density and composition of the radioactive particles of interest may vary, a self-absorption correction is required for the accurate determination of isotopic activities and ratios. This correction is carried out for each individual particle using the convenient gamma-ray emissions of (241)Am.

  7. Application of GUM Supplement 1 to uncertainty of Monte Carlo computed efficiency in gamma-ray spectrometry.

    PubMed

    Sima, Octavian; Lépy, Marie-Christine

    2016-03-01

    The uncertainty of quantities relevant in gamma-ray spectrometry (efficiency, transfer factor, self-attenuation FA and coincidence summing FC correction factors) is realistically evaluated by Monte Carlo propagation of the distributions characterizing the parameters on which these quantities depend. Probability density functions are constructed and summarized as recommended in the GUM Supplement 1 and compared with the values obtained using the traditional approach (GUM uncertainty framework). Special cases when this approach encounters difficulties (FC uncertainty due to the uncertainty of decay scheme parameters, effect of activity and matrix inhomogeneity on efficiency) are also discussed.

  8. Investigation of Failed TRISO Fuel Assay Using Gamma-Ray Spectrometry

    NASA Astrophysics Data System (ADS)

    Harp, Jason Michael

    uncertainties associated with direct comparison are nullified through the use of relative indicators. Each R/B model has a unique set of indicators that reflect the physical processes simulated in the model. Trends in the model indicators can be matched up with trends in indicators derived from the release spectra to validate either an entire model or validate the need to consider certain parameters in the creation of a complete and successful release to birth model. Gamma spectrometry is a useful tool for the understanding of fission gas release from failed TRISO particles. A better understanding of the processes that influence fission gas release will influence the fuel manufacturing and quality assurance protocols during the continued development of the VHTR. Future work in this area includes experiment in which the conditions can be better controlled to document the effects of temperature and fission rate in the fuel.

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

    SciTech Connect

    Lester, Rosemary; Wilkins, Colin; Chard, Patrick; Jaederstroem, Henrik; LeBlanc, Paul; Mowry, Rick; MacDonald, Sanders; Gunn, William

    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)

  10. A rapid dissolution procedure to aid initial nuclear forensics investigations of chemically refractory compounds and particles prior to gamma spectrometry.

    PubMed

    Reading, David G; Croudace, Ian W; Warwick, Phillip E; Britton, Richard

    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 ((210)Pb, (234)Th, (226)Ra, (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. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. gamma-Ray-mediated oxidative labeling for detecting protein conformational changes by electrospray mass spectrometry.

    PubMed

    Tong, Xin; Wren, J Clara; Konermann, Lars

    2008-03-15

    Exposure of proteins to hydroxyl radicals induces the incorporation of oxygen atoms into solvent-exposed side chains. Earlier studies have employed this approach for mapping protein-protein interactions in mass spectrometry-based footprinting experiments. This work explores whether the overall level of gamma-ray mediated oxidative labeling can be used for monitoring large-scale conformational changes. According to a recently developed kinetic model (Tong, X.; Wren, J. C.; Konermann, L. Anal. Chem. 2007, 79, 6376-6382), the apparent first-order rate constant for oxidative labeling can be approximated as k(app) = k(RAD)/([P](tot) + C/k(u)), where k(RAD) is the primary rate of *OH formation, [P](tot) is the protein concentration, C reflects the presence of competing radical deactivation channels, and ku is the rate constant at which hydroxyl radicals react with the protein. The current study introduces conformational effects into this model by proposing that k(u) = [see text for formula] , where N is the number of amino acids, alphai is a measure for the solvent exposure of residue i, and k(ch)(i) is the oxidation rate constant that would apply for a completely solvent-exposed side chain. Using myoglobin and cytochrome c as model systems, it is demonstrated that unfolding by addition of H(3)PO(4) increases k(app) by up to 30% and 70%, respectively. Unfolding by other commonly used denaturants such as organic acids or urea results in dramatically lower oxidation levels than for the native state, a behavior that is due to the radical scavenging activity of these substances (corresponding to an increased value of C). Control experiments on model peptides are suitable for identifying such "secondary" effects, i.e., factors that modify oxidation levels without being related to conformational changes. In conclusion, the overall *OH labeling level represents a viable probe of large-scale protein conformational changes only under conditions where secondary effects are known

  12. The radioactivity measurements in soils and fertilizers using gamma spectrometry technique.

    PubMed

    Boukhenfouf, Wassila; Boucenna, Ahmed

    2011-04-01

    Because of their mineral content, soils are naturally radioactive and one of the sources of radioactivity other than those of natural origin is mainly due to the extensive use of fertilizers. The main aim of this paper is to evaluate the fluxes of natural radionuclides in local production of phosphate fertilizers to determine the content of radioactivity in several commercial fertilizers produced in Algeria and to estimate their radiological impact in a cultivated soil even for the long-term exposure due to their application. For these purposes, virgin and fertilized soils were collected from outlying Setif region in Algeria and from phosphate fertilizers used in this area. Gamma spectrometry was exploited to determine activity concentration due to naturally occurring (226)Ra, (232)Th and (40)K in five types of samples (two different sorts of fertilizers, virgin and fertilized soils and well water used for irrigation) taken from Setif's areas. The results show that these radionuclides were present in an average concentration of 134.7 ± 24.1, 131.8 ± 16.7, 11644 ± 550 Bq/kg for the first fertilizer NPK and 190.3 ± 30, 117.2 ± 10.3, 5312 ± 249 Bq/kg for the second fertilizer (NPKs). For the virgin and the fertilized soils, the corresponding values were respectively 47.01 ± 7.3, 33 ± 7, 329.4 ± 19.7 Bq/kg and 53.2 ± 10.6, 50.0 ± 7, 311.4 ± 18.7 Bq/kg. For well water, the values were 1.93 and 0.12 Bq/kg; however the third value was below the Minimum Detectable Activity (MDA). The radium equivalent activity (Raeq) and the representative level index I(γr) for all samples were also calculated. The data were discussed and compared with those given in the literature. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Implementation of gamma-ray spectrometry in two real-time water monitors using NaI(Tl) scintillation detectors.

    PubMed

    Casanovas, R; Morant, J J; Salvadó, M

    2013-10-01

    In this study, the implementation of gamma-ray spectrometry in two real-time water monitors using 2 in. × 2 in. NaI(Tl) scintillation detectors is described. These monitors collect the water from the river through a pump and it is analyzed in a vessel, which is shielded with Pb. The full calibration of the monitors was performed experimentally, except for the efficiency curve, which was set using validated Monte Carlo simulations with the EGS5 code system. After the calibration, the monitors permitted the identification and quantification of the involved isotopes in a possible radioactive increment and made it possible to discard possible leaks in the nuclear plants. As an example, a radiological increment during rain is used to show the advantages of gamma-ray spectrometry. To study the capabilities of the monitor, the minimum detectable activity concentrations for (131)I, (137)Cs and (40)K are presented for different integration times. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Self-absorption correction factor applied to 129I measurement by direct gamma-X spectrometry for Fucus serratus samples

    NASA Astrophysics Data System (ADS)

    Lefèvre, O.; Bouisset, P.; Germain, P.; Barker, E.; Kerlau, G.; Cagnat, X.

    2003-06-01

    Self-absorption corrections have been determined for the energies characterising 129I below 40 keV in the frame of studying Fucus serratus samples by direct gamma-X spectrometry. This work was performed on a large spatio-temporal scale in order to integrate the fluctuations of the matrix. More than 200 samples monthly collected from January 1983 to December 1996 along the French Atlantic and English Channel coasts, have been measured as part of the Permanent Observatory of the radioactivity programme of the Institut de Radioprotection et de Sûreté Nucléaire (IRSN). A relationship has been established between experimental mass attenuation coefficients at low energy and the 40K concentrations of the samples, where the latter showed the same temporal variation as the 127I concentration (iodine stable isotope). Based on the mean correction factors determined in the present work, a simplified method is proposed to quantify the content of 129I. The direct gamma-X spectrometry results obtained in this way are in good agreement with those reported by Patti et al. (Radioprotection 23 (1988) 381) using neutron activation analysis for the samples collected between October 1983 and December 1984 at Herquemoulin, located near the La Hague reprocessing plant.

  15. Dating of sediments from four Swiss prealpine lakes with (210)Pb determined by gamma-spectrometry: progress and problems.

    PubMed

    Putyrskaya, V; Klemt, E; Röllin, S; Astner, M; Sahli, H

    2015-07-01

    In this paper the most important problems in dating lake sediments with unsupported (210)Pb are summarized and the progress in gamma-spectrometry of the unsupported (210)Pb is discussed. The main topics of these studies concern sediment samples preparation for gamma-spectrometry, measurement techniques and data analysis, as well as understanding of accumulation and sedimentation processes in lakes. The vertical distributions of artificial ((137)Cs, (241)Am, (239)Pu) and natural radionuclides ((40)K, (210,214)Pb, (214)Bi) as well as stable trace elements (Fe, Mn, Pb) in sediment cores from four Swiss lakes were used as examples for the interpretation, inter-comparison and validation of depth-age relations established by three (210)Pb-based models (CF-CSR, CRS and SIT). The identification of turbidite layers and the influence of the turbidity flows on the accuracy of sediment dating is demonstrated. Time-dependent mass sedimentation rates in lakes Brienz, Thun, Biel and Lucerne are discussed and compared with published data.

  16. Radiation hazards and lifetime risk assessment of tap water using liquid scintillation counting and high-resolution gamma spectrometry.

    PubMed

    Al-Shboul, K F; Alali, A E; Batayneh, I M; Al-Khodire, H Y

    2017-09-12

    In this work, two complementary techniques, viz. liquid scintillation counting and high-resolution gamma spectrometry are utilized to analyze radionuclides concentrations in tap water of Irbid governorate, Jordan, and study their correlation. Gross alpha and gross beta concentrations, in the tap water samples collected from the nine districts of Irbid governorate, ranged from <82 to 484 mBq/L with a mean of 295 mBq/L and from <216 to 984 mBq/L with a mean of 611 mBq/L, respectively. Furthermore, gamma spectrometry analysis, for the tap water samples, shows that the activity concentrations of (226)Ra, (232)Th, and (40)K ranged between <19 and 302 mBq/L, 24 to 119 mBq/L, and <101 to 342 mBq/L, respectively. There was a weak or even no correlation among the identified natural radionuclides with no trace of artificial radioactivity. In addition, the results of both techniques show that storing tap water in drilled wells leads to higher levels of radioactivity concentrations beyond the international permissible limits. Furthermore, the average lifetime risk and annual effective dose received by age-grouped inhabitants due to direct and indirect tap water consumption are evaluated, where most of the received dose is attributed to (226)Ra. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Data quality objectives for surface-soil cleanup operation using in situ gamma spectrometry for concentration measurements.

    PubMed

    Fong, S H; Alvarez, J L

    1997-02-01

    In situ gamma spectrometry is an efficient method for monitoring the progress of cleanup activities for radioactive contaminants in surface soil and for evaluating the attainment of cleanup standards. However, desired data precision and accuracy must be specified for such a detection system prior to the operation to ensure that the level of uncertainty associated with the concentration measurements is acceptable. A method for developing data quality objectives is described in this paper for in situ gamma spectrometry to achieve numerical goals for data precision and accuracy for cleanup operations. Concentration measurement for a radionuclide at its cleanup level must have a precision commensurate with the importance of cleanup decisions. The 95% lower limit of detection of the system is suggested to be about one tenth the expected system response at the cleanup level. The count time required to achieve the preferred 95% lower limit of detection, and hence the desired precision, can then be determined. The accuracy error arises from the overall calibration factor, which relates the detector responses (e.g., count rate) to physical quantities of interest (e.g., radionuclide soil concentration). The major source of error for the calibration factor using in situ gamma spectrometry is the misidentification of the type of the depth profile of radionuclide concentration in soil. If surrogate radionuclides are used, such as 241Am for plutonium, the variation in the concentration ratio would be another significant source of error. Soil sampling programs performed prior to a cleanup operation will greatly reduce the accuracy error for an in situ detection system, and the analysis of system errors may determine the degree of sampling required. The planning of such a program is discussed in the study. Uncertainty analysis using a Latin Hypercube sampling technique for the calibration factor is also demonstrated. The quantitative result of the uncertainty analysis is useful

  18. A method for the comparison of performance of gamma-ray spectrometry calibration cocktails.

    PubMed

    Legarda, F; Los Arcos, J M; Herranz, M

    2004-01-01

    In order to make quantitative assessments about the usefulness of different gamma-ray emitting radionuclide cocktails to carry out efficiency calibrations of gamma-ray spectrometers, a method has been developed that allows the comparison of their different performances and to optimize the choice of gamma energy lines for the radionuclides within a specific cocktail. The method has been applied to compare different cocktail configurations obtained from measurements made in the laboratory with monoenergetic radionuclides, and their relative performances are presented and discussed.

  19. Environmental Protection Agency (EPA) airborne gamma spectrometry system for environmental and emergency response surveys

    NASA Astrophysics Data System (ADS)

    Cardarelli, John, II; Thomas, Mark; Curry, Timothy

    2010-08-01

    The EPA Airborne Spectral Photometric Environmental Collection Technology (ASPECT) Program provides airborne ortho-rectified imagery, video, chemical and now radiological information directly to emergency response personnel via a commercial satellite link onboard the aircraft. EPA initiated the ASPECT Gamma Emergency Mapper GEM Project in 2008 to improve its airborne gamma-screening and mapping capability for monitoring any ground-based gamma contamination. This paper will provide an overview of the system, which can be configured to carry six 2"x4"x16" NaI(Tl) detectors and two 3"x3" LaBr3(Ce) detectors or eight 2"x4"x16" NaI(Tl) detectors. The paper will provide an overview of the analysis of gamma radiation spectra, system limitations, and emergency response applications.

  20. A broadband gamma-ray spectrometry using novel unfolding algorithms for characterization of laser wakefield-generated betatron radiation

    SciTech Connect

    Jeon, Jong Ho Nakajima, Kazuhisa Pathak, Vishwa Bandhu; Cho, Myung Hoon; Yoo, Byung Ju; Shin, Kang Woo; Kim, Hyung Taek; Sung, Jae Hee; Lee, Seung Ku; Choi, Il Woo; Rhee, Yong Joo; Shin, Jung Hun; Jo, Sung Ha; Hojbota, Calin; Cho, Byeoung Ick; Nam, Chang Hee

    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.

  1. A broadband gamma-ray spectrometry using novel unfolding algorithms for characterization of laser wakefield-generated betatron radiation.

    PubMed

    Jeon, Jong Ho; Nakajima, Kazuhisa; Kim, Hyung Taek; Rhee, Yong Joo; Pathak, Vishwa Bandhu; Cho, Myung Hoon; Shin, Jung Hun; Yoo, Byung Ju; Hojbota, Calin; Jo, Sung Ha; Shin, Kang Woo; Sung, Jae Hee; Lee, Seung Ku; Cho, Byeoung Ick; Choi, Il Woo; Nam, Chang Hee

    2015-12-01

    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.

  2. A convenient method for discriminating between natural and depleted uranium by gamma-ray spectrometry.

    PubMed

    Shoji, M; Hamajima, Y; Takatsuka, K; Honoki, H; Nakajima, T; Kondo, T; Nakanishi, T

    2001-08-01

    A convenient method for discriminating between natural and depleted uranium reagent was developed by measuring and analyzing the gamma-ray spectra of some reagents with no standard source. The counting rates (R) of photoelectric peaks of gamma-rays from nuclides with the same radioactivity divided by their emission probability (B) are expressed as a function of gamma-ray energy. The radioactivities of 234Th and 234mPa and 21.72 times that of 235U are equal to the radioactivity of 235U in natural uranium. Therefore, the plot of 21.72-fold R/B for 235U should be on a curve fitted to the points for 234Th and 234mPa in natural uranium. Depleted uranium with a 235U isotopic composition of less than 0.68% could be discriminated from natural uranium in the case of a reagent containing 4.0 g of uranium.

  3. Isotopic composition analysis and age dating of uranium samples by high resolution gamma ray spectrometry

    NASA Astrophysics Data System (ADS)

    Apostol, A. I.; Pantelica, A.; Sima, O.; Fugaru, V.

    2016-09-01

    Non-destructive methods were applied to determine the isotopic composition and the time elapsed since last chemical purification of nine uranium samples. The applied methods are based on measuring gamma and X radiations of uranium samples by high resolution low energy gamma spectrometric system with planar high purity germanium detector and low background gamma spectrometric system with coaxial high purity germanium detector. The ;Multigroup γ-ray Analysis Method for Uranium; (MGAU) code was used for the precise determination of samples' isotopic composition. The age of the samples was determined from the isotopic ratio 214Bi/234U. This ratio was calculated from the analyzed spectra of each uranium sample, using relative detection efficiency. Special attention is paid to the coincidence summing corrections that have to be taken into account when performing this type of analysis. In addition, an alternative approach for the age determination using full energy peak efficiencies obtained by Monte Carlo simulations with the GESPECOR code is described.

  4. Mathematical model of gamma-ray spectrometry borehole logging for quantitative analysis

    USGS Publications Warehouse

    Schimschal, Ulrich

    1981-01-01

    A technique for analyzing gamma-ray spectral-logging data has been developed, in which a digital computer is used to calculate the effects of gamma-ray attentuation in a borehole environment. The computer model allows for the calculation of the effects of lithology, porosity, density, and the thickness of a horizontal layer of uniformly distributed radioactive material surrounding a centralized probe in a cylindrical borehole. The computer program also contains parameters for the calculation of the effects of well casing, drilling fluid, probe housing, and losses through the sodium-iodide crystal. Errors associated with the commonly used mathematical assumption of a point detector are eliminated in this model. (USGS)

  5. Low-background gamma-ray spectrometry for the international monitoring system.

    PubMed

    Greenwood, L R; Cantaloub, M G; Burnett, J L; Myers, A W; Overman, C T; Forrester, J B; Glasgow, B G; Miley, H S

    2016-12-28

    PNNL has developed two low-background gamma-ray spectrometers in a new shallow underground laboratory, thereby significantly improving its ability to detect low levels of gamma-ray emitting fission or activation products in airborne particulate in samples from the IMS (International Monitoring System). The combination of cosmic veto panels, dry nitrogen gas to reduce radon and low background shielding results in a reduction of the background count rate by about a factor of 100 compared to detectors operating above ground at our laboratory.

  6. Low-background gamma-ray spectrometry for the international monitoring system

    DOE PAGES

    Greenwood, L. R.; Cantaloub, M. G.; Burnett, J. L.; ...

    2016-12-28

    PNNL has developed two low-background gamma-ray spectrometers in a new shallow underground laboratory, thereby significantly improving its ability to detect low levels of gamma-ray emitting fission or activation products in airborne particulate in samples from the IMS (International Monitoring System). Furthermore, the combination of cosmic veto panels, dry nitrogen gas to reduce radon and low background shielding results in a reduction of the background count rate by about a factor of 100 compared to detectors operating above ground at our laboratory.

  7. Aerial Explorers

    NASA Technical Reports Server (NTRS)

    Young, Larry A.; Pisanich, Greg; Ippolito, Corey

    2005-01-01

    This paper presents recent results from a mission architecture study of planetary aerial explorers. In this study, several mission scenarios were developed in simulation and evaluated on success in meeting mission goals. This aerial explorer mission architecture study is unique in comparison with previous Mars airplane research activities. The study examines how aerial vehicles can find and gain access to otherwise inaccessible terrain features of interest. The aerial explorer also engages in a high-level of (indirect) surface interaction, despite not typically being able to takeoff and land or to engage in multiple flights/sorties. To achieve this goal, a new mission paradigm is proposed: aerial explorers should be considered as an additional element in the overall Entry, Descent, Landing System (EDLS) process. Further, aerial vehicles should be considered primarily as carrier/utility platforms whose purpose is to deliver air-deployed sensors and robotic devices, or symbiotes, to those high-value terrain features of interest.

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

    SciTech Connect

    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.

  9. Gamma spectrometry efficiency calibration using Monte Carlo methods to measure radioactivity of 137Cs in food samples.

    PubMed

    Alrefae, T

    2014-12-01

    A simple method of efficiency calibration for gamma spectrometry was performed. This method, which focused on measuring the radioactivity of (137)Cs in food samples, was based on Monte Carlo simulations available in the free-of-charge toolkit GEANT4. Experimentally, the efficiency values of a high-purity germanium detector were calculated for three reference materials representing three different food items. These efficiency values were compared with their counterparts produced by a computer code that simulated experimental conditions. Interestingly, the output of the simulation code was in acceptable agreement with the experimental findings, thus validating the proposed method. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. The influence of exogenous conditions on mobile measured gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    Dierke, C.; Werban, U.; Dietrich, P.

    2012-12-01

    In the past, gamma ray measurements have been used for geological surveys and exploration using airborne and borehole logging systems. For these applications, the relationships between the measured physical parameter - the concentration of natural gamma emitters 40K, 238U and 232Th - and geological origin or sedimentary developments are well described. Based on these applications and knowledge in combination with adjusted sensor systems, gamma ray measurements are used to derive soil parameters to create detailed soil maps e.g., in digital soil mapping (DSM) and monitoring of soils. Therefore, not only qualitative but also quantitative comparability is necessary. Grain size distribution, type of clay minerals and organic matter content are soil parameters which directly influence the gamma ray emitter concentration. Additionally, the measured concentration is influenced by endogenous processes like soil moisture variation due to raining events, foggy weather conditions, or erosion and deposition of material. A time series of gamma ray measurements was used to observe changes in gamma ray concentration on a floodplain area in Central Germany. The study area is characterised by high variations in grain size distribution and occurrence of flooding events. For the survey, we used a 4l NaI(Tl) detector with GPS connection mounted on a sledge, which is towed across the field sites by a four-wheel-vehicle. The comparison of data from different time steps shows similar structures with minor variation between the data ranges and shape of structures. However, the data measured during different soil moisture contents differ in absolute value. An average increase of soil moisture of 36% leads to a decrease of Th (by 20%), K (by 29%), and U (by 41%). These differences can be explained by higher attenuation of radiation during higher soil moisture content. The different changes in nuclide concentration will also lead to varying ratios. We will present our experiences concerning

  11. In-situ ground gamma spectrometry — an effective tool for geological mapping (the Male Karpaty Mts., Slovakia)

    NASA Astrophysics Data System (ADS)

    Mojzeš, Andrej; Porubčanová, Barbara

    2016-06-01

    This contribution presents the results of profile in-situ gamma spectrometry measurements that sought to determine the content of natural radionuclides 40K, 238U and 232Th in a near surface horizon of rocks, their weathering cover and soils in the area of the Malé Karpaty Mts. It is widely established that the exploration of radioactivity of bedrocks and cover rocks can be a very effective and useful tool for both geological mapping, for identifying deposits of mineral resources, and even addressing the issues of structural and tectonic geology. This assertion is equally confirmed by the ground gamma spectrometry measurements carried out as part of this case study on larger scales, seeking more detailed geological structure solutions. The results obtained provide a welcome addition to an already existing database, which monitors the content of naturally occurring radionuclides individually for every rock lithotype of the Western Carpathians, by elaborating on the data collected by previous research and by updating this database for any future needs. The presented results confirmed the low to medium radioactivity levels of rocks and soils in the studied area. The highest values were detected in granitoids and metamorfic phyllitic rocks of the Malé Karpaty Mts. core; the lowest values were detected in carbonates, arenaceous sediments and, above all, amphibolite bodies. In this way, the presented results of the interpreted profile (P5) confirm the model of local geological structure as represented on the most up-to-date edition of the geological map of the Male Karpaty Mts. (Polak et al. 2011).

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

    NASA Astrophysics Data System (ADS)

    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.

  13. The Application of High-Resolution Gamma-Ray Spectrometry (HRGS) to Nuclear Safeguards, Nonproliferation, and Arms Control Activities

    SciTech Connect

    Kane, Walter R.; Lemley, James R.; Forman, Leon

    1997-12-31

    While well-developed methodologies exist for the employment of high- resolution gamma ray spectrometry (HRGS) in determining the isotopic composition of plutonium samples, the potential capabilities of such measurements in determining the properties of nuclear materials otherwise remain largely unexploited. These measurements contain information sufficiently detailed such that not only can the isotopic composition of uranium and plutonium materials be determined, but the details of the spectrum obtained will depend reproducibly upon other factors including the total mass, density, chemical composition, and geometrical configuration of the material, and for certain materials, the elapsed time since chemical processing. The potential thus exists to obtain a `gamma-ray fingerprint` for typical containers or assemblies of nuclear material which will then serve to identify that class of item in a later confirmatory measurement. These measurements have the additional advantage that, by comparison with active interrogation techniques which usually require the introduction of some extraneous form of radiation or other intrusive activity, they are totally passive, and thus impose only minimal additional safety or regulatory burdens on the operators. In the application of these measurements to the verification of treaty-limited items, where the information acquired may be sensitive in nature, the use of the CIVET (Controlled Intrusiveness Verification Technique) approach, where a computer-based interface is employed to limit access to the information obtained, may be followed.

  14. Gamma spectrometry and chemical characterization of ceramic seeds with samarium-153 and holmium-166 for brachytherapy proposal.

    PubMed

    Valente, Eduardo S; Campos, Tarcísio P R

    2010-12-01

    Ceramic seeds were synthesized by the sol-gel technique with Si:Sm:Ca and Si:Ho:Ca. One set of seeds was irradiated in the TRIGA type nuclear reactor IPR-R1 and submitted to instrumental neutron activation analysis (INAA), K(0) method, to determine mass percentage concentration of natural samarium and holmium in the seed as well as to determine all existing radionuclides and their activities. Attention was paid to discrimination of Si-31, Ca-40, Ca-45, Ca-47, Ca-49, Sm-145, Sm-155, Sm-153 and Ho-166. A second sample was submitted to atomic emission spectrometry (ICP-AES) also to determine samarium and holmium concentrations in weight. A third sample was submitted to X-ray fluorescence spectrometry to qualitatively determine chemical composition. The measured activity was due to Sm-153 and Ho-166 with a well-characterized gamma spectrum. The X-ray fluorescence spectrum demonstrated that there is no discrepancy in seed composition. The maximum ranges in the water of beta particles from Sm-153 and Ho-166 decay were evaluated, as well as the dose rate and total dose delivered within the volume delimited by the range of the beta particles. The results are relevant for investigation of the viability of producing Sm-153 and Ho-166 radioactive seeds for use in brachytherapy.

  15. NURE aerial gamma-ray and magnetic reconnaissance survey of portions of New Mexico, Arizona and Texas. Volume II. New Mexico-Las Cruces NI 13-10 Quadrangle. Final report

    SciTech Connect

    Not Available

    1981-09-01

    The results of a high-sensitivity, aerial gamma-ray spectrometer and magnetometer survey of the Las Cruces two degree quadrangle, New Mexico, are presented. Instrumentation and methods are described in Volume 1 of this final report. The work was done by Carson Helicopters, Inc., and International Exploration, Inc. The work was performed for the US Department of Energy - National Uranium Resource Evaluation (NURE) program. Analysis of this radiometric data yielded 192 statistically significant eU anomalies. Of this number, thirty-nine were considered to be of sufficient strength to warrant further investigation.

  16. The Study of Equilibrium factor between Radon-222 and its Daughters in Bangkok Atmosphere by Gamma-ray Spectrometry

    NASA Astrophysics Data System (ADS)

    Rujiwarodom, Rachanee

    2010-05-01

    To study the Equilibrium between radon-222 and its daughters in Bangkok atmosphere by Gamma-ray spectrometry, air sample were collected on 48 activated charcoal canister and 360 glass fiber filters by using a high volume jet-air sampler during December 2007 to November 2008.The Spectra of gamma-ray were measured by using a HPGe (Hyper Pure Germanium Detector). In the condition of secular equilibrium obtaining between Radon-222 and its decay products, radon-222 on activated charcoal canister and its daughters on glass fiber filters collected in the same time interval were calculated. The equilibrium factor (F) in the open air had a value of 0.38 at the minimum ,and 0.75 at the maximum. The average value of equilibrium factor (F) was 0.56±0.12. Based on the results, F had variations with a maximum value in the night to the early morning and decreased in the afternoon. In addition, F was higher in the winter than in the summer. This finding corresponds with the properties of the Earth atmosphere. The equilibrium factor (F) also depended on the concentration of dust in the atmosphere. People living in Bangkok were exposed to average value of 30 Bq/m3 of Radon-222 in the atmosphere. The equilibrium factor (0.56±0.12) and the average value of Radon-222 showed that people were exposed to alpha energy from radon-222 and its daughters decay at 0.005 WL(Working Level) which is lower than the safety standard at 0.02 WL. Keywords: Radon, Radon daughters , equilibrium factor, Gamma -ray spectrum analysis ,Bangkok ,Thailand

  17. Measurement of gamma radiation levels in soil samples from Thanjavur using γ-ray spectrometry and estimation of population exposure

    PubMed Central

    Senthilkumar, B.; Dhavamani, V.; Ramkumar, S.; Philominathan, P.

    2010-01-01

    This study assesses the level of terrestrial gamma radiation and associated dose rates from the naturally occurring radionuclides 232Th, 238U and 40K in 10 soil samples collected from Thanjavur (Tamil Nadu, India) using γ-ray spectrometry. The activity profile of radionuclides has clearly showed the existence of low level activity in Thanjavur. The geometric mean activity concentrations of 232Th, 238U and 40K is 42.9±9.4 Bq.kg−1, 14.7±1.7 Bq.kg−1 and 149.5±3.1 Bq.kg−1 respectively are derived from all the soil samples studied. The activity concentration of 232Th, 238U and 40K in soil is due to the presence of metamorphic rocks like shale, hornblende-biotite gneiss and quartzofeldspathic gneiss in these areas. Gamma absorbed dose rates in air outdoors were calculated to be in the range between 32 nGy.h−1 and 59.1 nGy.h−1 with an arithmetic mean of 43.3 ±9 nGy.h−1. This value is lesser than the population weighted world-averaged of 60 nGy.h−1. Inhabitants of Thanjavur are subjected to external gamma radiation exposure (effective dose) ranging between 39.2 and 72.6 μSv.y−1 with an arithmetic mean of 53.1±11 μSv.y−1. The values of the external hazard index determined from the soil radioactivity of the study area are less than the recommended safe levels. PMID:20177570

  18. Development of low level 226Ra analysis for live fish using gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    Chandani, Z.; Prestwich, W. V.; Byun, S. H.

    2017-06-01

    A low level 226Ra analysis method for live fish was developed using a 4π NaI(Tl) gamma-ray spectrometer. In order to find out the best algorithm for accomplishing the lowest detection limit, the gamma-ray spectrum from a 226Ra point was collected and nine different methods were attempted for spectral analysis. The lowest detection limit of 0.99 Bq for an hour counting occurred when the spectrum was integrated in the energy region of 50-2520 keV. To extend 226Ra analysis to live fish, a Monte Carlo simulation model with a cylindrical fish in a water container was built using the MCNP code. From simulation results, the spatial distribution of the efficiency and the efficiency correction factor for the live fish model were determined. The MCNP model will be able to be conveniently modified when a different fish or container geometry is employed as fish grow up in real experiments.

  19. Characterisation of imperial college reactor centre legacy waste using gamma-ray spectrometry

    SciTech Connect

    Shuhaimi, Alif Imran Mohd

    2016-01-22

    Waste characterisation is a principal component in waste management strategy. The characterisation includes identification of chemical, physical and radiochemical parameters of radioactive waste. Failure to determine specific waste properties may result in sentencing waste packages which are not compliant with the regulation of long term storage or disposal. This project involved measurement of intensity and energy of gamma photons which may be emitted by radioactive waste generated during decommissioning of Imperial College Reactor Centre (ICRC). The measurement will use High Purity Germanium (HPGe) as Gamma-ray detector and ISOTOPIC-32 V4.1 as analyser. In order to ensure the measurements provide reliable results, two quality control (QC) measurements using difference matrices have been conducted. The results from QC measurements were used to determine the accuracy of the ISOTOPIC software.

  20. Gamma ray spectrometry logs as a hydrocarbon indicator for clastic reservoir rocks in Egypt.

    PubMed

    Al-Alfy, I M; Nabih, M A; Eysa, E A

    2013-03-01

    Petroleum oil is an important source for the energy in the world. The Gulf of Suez, Nile Delta and South Valley are important regions for studying hydrocarbon potential in Egypt. A thorium normalization technique was applied on the sandstone reservoirs in the three regions to determine the hydrocarbon potentialities zones using the three spectrometric radioactive gamma ray-logs (eU, eTh and K% logs). The conventional well logs (gamma-ray, deep resistivity, shallow resistivity, neutron, density and sonic logs) are analyzed to determine the net pay zones in these wells. Indices derived from thorium normalized spectral logs indicate the hydrocarbon zones in petroleum reservoirs. The results of this technique in the three regions (Gulf of Suez, Nile Delta and South Valley) are in agreement with the results of the conventional well log analyses by ratios of 82%, 78% and 71% respectively.

  1. Characterisation of imperial college reactor centre legacy waste using gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    Shuhaimi, Alif Imran Mohd

    2016-01-01

    Waste characterisation is a principal component in waste management strategy. The characterisation includes identification of chemical, physical and radiochemical parameters of radioactive waste. Failure to determine specific waste properties may result in sentencing waste packages which are not compliant with the regulation of long term storage or disposal. This project involved measurement of intensity and energy of gamma photons which may be emitted by radioactive waste generated during decommissioning of Imperial College Reactor Centre (ICRC). The measurement will use High Purity Germanium (HPGe) as Gamma-ray detector and ISOTOPIC-32 V4.1 as analyser. In order to ensure the measurements provide reliable results, two quality control (QC) measurements using difference matrices have been conducted. The results from QC measurements were used to determine the accuracy of the ISOTOPIC software.

  2. Using gamma spectrometry indicators to detect and quantify fission products changes in irradiated fuel

    SciTech Connect

    Loubet, L.; Martella, Th.

    2015-07-01

    A new analysis method based on gamma scanning of fission products on irradiated rods is presented. Indicators calculated from this method can be used for the qualitative treatment and comparison of irradiated rods from PWR, SFR or and MTR. Differences in the behavior of fission products (FP) can thus be quantified. Phenomena such as migration or geometrical changes in pellets should thus benefit from these accurate, yet quickly and easily achievable results. (authors)

  3. Simultaneous measurements of indoor radon, radon-thoron progeny and high-resolution gamma spectrometry in Greek dwellings.

    PubMed

    Clouvas, A; Xanthos, S; Antonopoulos-Domis, M

    2006-01-01

    Simultaneous indoor radon, radon-thoron progeny and high-resolution in situ gamma spectrometry measurements, with portable high-purity Ge detector were performed in 26 dwellings of Thessaloniki, the second largest town of Greece, during March 2003-January 2005. The radon gas was measured with an AlphaGUARD ionisation chamber (in each of the 26 dwellings) every 10 min, for a time period between 7 and 10 d. Most of the values of radon gas concentration are between 20 and 30 Bq m(-3), with an arithmetic mean of 34 Bq m(-3). The maximum measured value of radon gas concentration is 516 Bq m(-3). The comparison between the radon gas measurements, performed with AlphaGUARD and short-term electret ionisation chamber, shows very good agreement, taking into account the relative short time period of the measurement and the relative low radon gas concentration. Radon and thoron progeny were measured with a SILENA (model 4s) instrument. From the radon and radon progeny measurements, the equilibrium factor F could be deduced. Most of the measurements of the equilibrium factor are within the range 0.4-0.5. The mean value of the equilibrium factor F is 0.49 +/- 0.10, i.e. close to the typical value of 0.4 adopted by UNSCEAR. The mean equilibrium equivalent thoron concentration measured in the 26 dwellings is EEC(thoron) = 1.38 +/- 0.79 Bq m(-3). The mean equilibrium equivalent thoron to radon ratio concentration, measured in the 26 dwellings, is 0.1 +/- 0.06. The mean total absorbed dose rate in air, owing to gamma radiation, is 58 +/- 12 nGy h(-1). The contribution of the different radionuclides to the total indoor gamma dose rate in air is 38% due to 40K, 36% due to thorium series and 26% due to uranium series. The annual effective dose, due to the different source terms (radon, thoron and external gamma radiation), is 1.05, 0.39 and 0.28 mSv, respectively.

  4. Assay for uranium and determination of disequilibrium by means of in situ high resolution gamma-ray spectrometry

    USGS Publications Warehouse

    Tanner, Allan B.; Moxham, Robert M.; Senftle, F.E.

    1977-01-01

    Two sealed sondes, using germanium gamma-ray detectors cooled by melting propane, have been field tested to depths of 79 m in water-filled boreholes at the Pawnee Uranium Mine in Bee Co., Texas. When, used as total-count devices, the sondes are comparable in logging speed and counting rate with conventional scintillation detectors for locating zones of high radioactivity. When used with a multichannel analyzer, the sondes are detectors with such high resolution that individual lines from the complex spectra of the uranium and thorium series can be distinguished. Gamma rays from each group of the uranium series can be measured in ore zones permitting determination of the state of equilibrium at each measurement point. Series of 10-minute spectra taken at 0.3- to 0.5-m intervals in several holes showed zones where maxima from the uranium group and from the 222Rn group were displaced relative to each other. Apparent excesses of 230Th at some locations suggest that uranium-group concentrations at those locations were severalfold greater some tens of kiloyears, ago. At the current state of development a 10-minute count yields a sensitivity of about 80 ppm U308. Data reduction could in practice be accomplished in about 5 minutes. The result is practically unaffected by disequilibrium or radon contamination. In comparison with core assay, high-resolution spectrometry samples a larger volume; avoids problems due to incomplete core recovery, loss of friable material to drilling fluids, and errors in depth and marking; and permits use of less expensive drilling methods. Because gamma rays from the radionuclides are accumulated simultaneously, it also avoids the problems inherent in trying to correlate logs made in separate runs with different equipment. Continuous-motion delayed-gamma activation by a 163-?g 252Cf neutron source attached to the sonde yielded poor sensitivity. A better neutron-activation method, in which the sonde is moved in steps so as to place the detector

  5. In situ subterranean determination of actinides by high-resolution gamma-ray spectrometry

    SciTech Connect

    Brodzinski, R. L.

    1981-04-01

    A system utilizing high resolution germanium diode gamma-ray spectroscopy for the simple, safe, and economical in situ determination of actinides is described. Six isotopes, /sup 235/U, /sup 238/U, /sup 237/Np, /sup 239/Pu, /sup 241/Pu, and /sup 241/Am, can be simultaneously measured at the 10 nCi g/sup -1/ level in less than 7 minutes. Collimators provide for measurement of horizontal strata as thin as 1 cm or solid angles as small as 0.1 steradians. Information obtainable with the system is discussed and compared to that obtainable with neutron activation/detection systems.

  6. Ultra low-level gamma ray spectrometry of thorium in human bone samples.

    PubMed

    Martínez Canet, M J; Hult, M; Johnston, P N; Lambrichts, I

    2001-01-01

    Following the use of in vivo measurements of 210Pb to estimate retrospectively radon exposure, interest has been expressed in the use of in vivo measurements of 208Tl to estimate thorium intake. To aid with calibration and to determine the optimum part of the body on which in vivo measurements should be made, the distribution of 208Tl and 228Ac amongst different human bones was measured in the underground laboratory HADES. The 208Tl activity was determined by the 2614.5 keV and the 583.2 keV gamma ray lines. The 225Ac activity was determined by the 911.2 keV and the 969.0 keV gamma ray lines. The background under those peaks when measured on the 106% relative efficiency coaxial HPGe detector in HADES is of the order of 1 d(-1), resulting in detection limits in the order of 1 mBq for both radionuclides for a typical 10 g bone sample and for a measuring time of I week.

  7. Radiometric analysis of construction materials using HPGe gamma-ray spectrometry.

    PubMed

    Khandaker, M U; Jojo, P J; Kassim, H A; Amin, Y M

    2012-11-01

    Concentrations of primordial radionuclides in common construction materials collected from the south-west coastal region of India were determined using a high-purity germanium gamma-ray spectrometer. Average specific activities (Bq kg(-1)) for (238)U((226)Ra) in cement, brick, soil and stone samples were obtained as 54 ± 13, 21 ± 4, 50 ± 12 and 46 ± 8, respectively. Respective values of (232)Th were obtained as 65 ± 10, 21 ± 3, 58 ± 10 and 57 ± 12. Concentrations of (40)K radionuclide in cement, brick, soil and stone samples were found to be 440 ± 91, 290 ± 20, 380 ± 61 and 432 ± 64, respectively. To evaluate the radiological hazards, radium equivalent activity, various hazard indices, absorbed dose rate and annual effective dose have been calculated, and compared with the literature values. Obtained data could be used as reference information to assess any radiological contamination due to construction materials in future.

  8. Optimized background reduction in low-level gamma-ray spectrometry at a surface laboratory.

    PubMed

    Hurtado, S; García-León, M; García-Tenorio, R

    2006-09-01

    The background of a coaxial Ge detector placed at a surface laboratory has been reduced by means of a background reduction setup consisting of a passive shield of low-activity lead, a simple radon suppression system and an active shield with a plastic scintillation plate. In particular, we have devoted our efforts to in-depth optimization of each parameter associated with different anticoincidence setups and to their subsequent intercomparison. The overall performance of the active shield was improved by using the optimum time parameters for each setup. The final objective is to decrease the cosmic-ray background and, by this way, to reduce the detection limits of gamma-ray spectrometers at conventional laboratories, and consequently make them competitive for different measurements like (210)Pb dating.

  9. Determination of Copper by Neutron Activation Analysis in Conjunction with Compton Suppression Gamma Spectrometry

    SciTech Connect

    W. H. Zhang; A. Chatt

    2000-06-04

    Copper is considered to be an essential element. Its accurate determination in tissues, foods, and other biological materials is needed to study the effect of copper on human nutrition and health. Using and Advance Prediction Computer Program, it has been shown that short-lived {sup 66}Cu (half-life = 5.09 min) can be used to determine copper in biological materials by instrumental neutron activation analysis (INAA). However, it is seldom done in practice-in particular, for low copper content in high-salt biological materials-because of the Compton background interference from nuclides such as {sup 28}Al, {sup 38}Cl, and {sup 24}Na. To eliminate the Compton interference, a preconcentration NAA method has recently been developed in our laboratory using reversed-phase extraction chromatography of copper followed by short irradiation and conventional gamma-spectrometric counting of {sup 66}Cu; the detection limit is {approx}5 ppb.

  10. PC/FRAM: New capabilities for the gamma-ray spectrometry measurement of plutonium isotopic composition

    SciTech Connect

    Sampson, T.E.; Kelley, T.A.; Cremers, T.L.; Konkel, T.R.; Friar, R.J.

    1995-10-01

    We describe the new capability of and.present measurement results from the PC/FRAM plutonium isotopic analysis code. This new code allows data acquisition from a single coaxial germanium detector and analysis over an energy range from 120 keV to above I MeV. For the first time we demonstrate a complete isotopic analysis using only gamma rays greater than 200 keV in energy. This new capability allows the measurement of the plutonium isotopic composition of items inside shielded or heavy-walled containers without having to remove the items from the container. This greatly enhances worker safety by reducing handling and the resultant radiation exposure. Another application allows international inspectors to verify the contents of items inside sealed, long-term storage containers that may not be opened for national security or treaty compliance reasons. We present measurement results for traditional planar germanium detectors as well as coaxial detectors measuring shielded and unshielded samples.

  11. Detection of frozen salt in pipes using gamma-ray spectrometry of potassium self-activity

    SciTech Connect

    Grena, Roberto; Scafe, Raffaele; Pisacane, Fabrizio; Pilato, Renzo; Crescenzi, Tommaso; Mazzei, Domenico

    2010-01-15

    Solar plants that use molten salts as heat transfer fluid need careful control to avoid the freezing of the salt in the pipes; if such a problem occurs, a diagnostic instrument to localize where is the frozen salt plug and to determine its length is useful. If the salt contains potassium (as is the case of the most common mixture used in solar plants, NaNO{sub 3}/KNO{sub 3} 60/40% by weight), the gamma decay of the natural unstable isotope {sup 40}K can be exploited to detect the frozen salt in a non-invasive way. Simulations and experimental results regarding the detectability of such plugs with different masses/lengths are presented. (author)

  12. Quantification of gamma-aminobutyric acid in Sri Lankan tea by means of ultra performance tandem mass spectrometry.

    PubMed

    Carvalho, Elisabete; Punyasiri, P A Nimal; Somasiri, H P P Sudarshana; Abeysinghe, I Sarath B; Martens, Stefan

    2014-04-01

    Gamma-Aminobutyric acid (GABA), an important bioactive component of tea, acts as a major inhibitory neurotransmitter and is considered to influence other physiological processes in human as well as in planta. In the hereby presented study, the content of this valuable metabolite was investigated in two novel types of Ceylon Tea, explicitly "Silver Tips" and "White Tea", originating from minimally processed buds of the unique cultivar, "TRI 2043". The samples were subjected to hot water infusion, equivalent to the traditional beverage preparation procedure, and analyzed by means of hydrophilic interaction ultra performance liquid chromatography coupled to tandem mass spectrometry (HILIC LC-MS/MS). The registered GABA levels were compared with those obtained for the classic "Black Tea" and "Green Tea" samples from Sri Lanka. A high variation of GABA content was observed among the different tea types, especially in the case of "Silver Tips" and "White Tea", indicating the crucial influence of the manufacturing procedure (processing extent) on the final abundance of the bioactive component of interest. Furthermore, "White Tea" samples boasted the highest GABA concentration reported for this type of tea so far, reaching up to 50% of that characteristic of the high-priced "GABA Tea". Therefore, "White Tea" and "Silver Tips" were proved to be high quality tea with amounts of gamma-aminobutyric acid comparable with those described for similar types before. To our knowledge, this is the first report on HILIC LC-MS/MS application for the quantification of GABA and for in-depth characterization of teas from Sri Lanka.

  13. Theoretical determination of gamma spectrometry systems efficiency based on probability functions. Application to self-attenuation correction factors

    NASA Astrophysics Data System (ADS)

    Barrera, Manuel; Suarez-Llorens, Alfonso; Casas-Ruiz, Melquiades; Alonso, José J.; Vidal, Juan

    2017-05-01

    A generic theoretical methodology for the calculation of the efficiency of gamma spectrometry systems is introduced in this work. The procedure is valid for any type of source and detector and can be applied to determine the full energy peak and the total efficiency of any source-detector system. The methodology is based on the idea of underlying probability of detection, which describes the physical model for the detection of the gamma radiation at the particular studied situation. This probability depends explicitly on the direction of the gamma radiation, allowing the use of this dependence the development of more realistic and complex models than the traditional models based on the point source integration. The probability function that has to be employed in practice must reproduce the relevant characteristics of the detection process occurring at the particular studied situation. Once the probability is defined, the efficiency calculations can be performed in general by using numerical methods. Monte Carlo integration procedure is especially useful to perform the calculations when complex probability functions are used. The methodology can be used for the direct determination of the efficiency and also for the calculation of corrections that require this determination of the efficiency, as it is the case of coincidence summing, geometric or self-attenuation corrections. In particular, we have applied the procedure to obtain some of the classical self-attenuation correction factors usually employed to correct for the sample attenuation of cylindrical geometry sources. The methodology clarifies the theoretical basis and approximations associated to each factor, by making explicit the probability which is generally hidden and implicit to each model. It has been shown that most of these self-attenuation correction factors can be derived by using a common underlying probability, having this probability a growing level of complexity as it reproduces more precisely

  14. Design and implementation of a mobile gamma spectrometry system to in vivo measure the accumulated activity of (131)I in patients with thyroid diseases.

    PubMed

    Bahamonde, Sebastián; Díaz-Londoño, Gloria M; García, Marcía; Albornoz, Felipe; Andrade, Pablo

    2017-08-13

    The design and implementation of a mobile gamma spectrometry system to in vivo measure the accumulated activity of (131)I in whole body and thyroid of patients with thyroid diseases are presented in this work. This system may be used for both pre-therapeutic and post-therapeutic dosimetry calculations. It consists of a detector and a movable support that allows its movement from one place to another. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Visualization of spatial distribution of gamma-aminobutyric acid in eggplant (Solanum melongena) by matrix-assisted laser desorption/ionization imaging mass spectrometry.

    PubMed

    Goto-Inoue, Naoko; Setou, Mitsutoshi; Zaima, Nobuhiro

    2010-01-01

    We applied imaging mass spectrometry (IMS) to determine the spatial distribution of gamma-aminobutyric acid (GABA). We found that GABA had a specific localization in seeds. We also visualized various biomolecules as well as GABA with higher spatial resolution than in the previous report. Our work suggests that IMS might be a powerful tool for exploring functional food factors, investigating the specific distribution of nutrients in unused natural resources, and evaluating the quality of functional foods.

  16. Determination of 137Cs activity in soil from Qatar using high-resolution gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    Al-Sulaiti, Huda; Nasir, Tabassum; Al Mugren, K. S.; Alkhomashi, N.; Al-Dahan, N.; Al-Dosari, M.; Bradley, D. A.; Bukhari, S.; Matthews, M.; Regan, P. H.; Santawamaitre, T.; Malain, D.; Habib, A.; Al-Dosari, Hanan; Al Sadig, Ibrahim; Daar, Eman

    2016-10-01

    With interest in establishing baseline concentrations of 137Cs in soil from the Qatarian peninsula, we focus on determination of the activity concentrations in 129 soil samples collected across the State of Qatar prior to the 2011 Fukushima Dai-ichi nuclear power plant accident. As such, the data provides the basis of a reference map for the detection of releases of this fission product. The activity concentrations were measured via high-resolution gamma-ray spectrometry using a hyper-pure germanium detector enclosed in a copper-lined passive lead shield that was situated in a low-background environment. The activity concentrations ranged from 0.21 to 15.41 Bq/kg, with a median value of 1 Bq/kg, the greatest activity concentration being observed in a sample obtained from northern Qatar. Although it cannot be confirmed, it is expected that this contamination is mainly due to releases from the Chernobyl accident of 26 April 1986, there being a lack of data from Qatar before the accident. The values are typically within but are sometimes lower than the range indicated by data from other countries in the region. The lower values than those of others is suggested to be due to variation in soil characteristics as well as metrological factors at the time of deposition.

  17. Radon loss from encapsulated sediments in Ge gamma-ray spectrometry for the annual radiation dose determination in luminescence dating

    NASA Astrophysics Data System (ADS)

    de Corte, F.; Vandenberghe, D.; de Wispelaere, A.; Buylaert, J.-P.; van den Haute, P.

    2006-01-01

    In Ge gamma-ray spectrometry for the annual radiation dose determination in the luminescence dating of sediments, the picture of 226Ra enrichment or depletion (in the 238U decay series) obtained via measurement of its 214Pb and 214Bi daughters may be disturbed by the 222Rn-content of the sample being decreased due to manipulations such as drying and pulverizing. Therefore, it is common practice to start the measurement only about 1 month after encapsulating the material, after which the 226Ra(1600 a)- 222Rn(3.82 d) mother-daughter equilibrium is re-established. Evidently, this only holds on condition that no significant escape of Rn occurs out of the sediment after making it up for counting. In order to experimentally investigate this effect, in the present work measurements were carried out with various types of dried and pulverized sediments that were either encapsulated in screw-cap polystyrene vials or in sealed glass containers, or that were mixed with molten wax followed by solidification in a cylindrical geometry. From the results obtained, it could be concluded that preparation and counting of the sediment-wax mixture is the method of choice.

  18. Development and application of Marinelli beaker standards for monitoring radioactivity in Dairy-Products by gamma-ray spectrometry.

    PubMed

    Lavi, N; Alfassi, Z B

    2004-12-01

    Marinelli (reentrant) beakers are recommended for measurement of low-activity radioactive environmental samples, in both liquid and solid phase. The preparation of Marinelli beaker standards of milk powder containing 232ThO2 at secular equilibrium with its daughter radionuclides was studied. Standards were prepared by mixing of known amounts of solid ThO2 and milk powder. The densities of the standards were 0.5-0.7 kg dm(-3). Measurements of calibrated Marinelli beaker standards with HPGe detector showed that the energy dependence of the efficiency is similar to that of a point source, i.e. an almost linear dependence of log-efficiency vs. log-energy in the 200-2000 keV range, however the parabolic correlation fits better. The validity of these standards was checked by comparison with certified standard reference material IAEA-152-Milk powder containing radiocesium and radiopotassium. The results obtained were found to be in a good agreement with the published certified data. The limit of detection for the determination of radiocesium by gamma ray spectrometry under the prevailing experimental conditions is 0.03 Bq (i.e. 0.8 pCi), for samples of dairy products having lower densities of 0.7 kg dm(-1).

  19. Comparison of SensL and Hamamatsu 4×4 channel SiPM arrays in gamma spectrometry with scintillators

    NASA Astrophysics Data System (ADS)

    Grodzicka-Kobylka, M.; Szczesniak, T.; Moszyński, M.

    2017-06-01

    The market of Silicon Photomultipliers (SiPMs) consists of many manufacturers that produce their detectors in different technology. Hamamatsu (Japan) and SensL (Ireland) seems to be the most popular companies that produce large SiPM arrays. The aim of this work is characterization and comparison of 4×4 channel SiPM arrays produced by these two producers. Both of the tested SiPMs are made in through-silicon via (TSV) technology, consist of 16, 3×3 mm avalanche photodiode (APD) cells and have fill factor slightly above 60%. The largest difference is a single APD cell size and hence total number of APD cells (55,424 for Hamamatsu, 76,640 for SensL). In the case of SensL SiPM, its spectral response characteristics is shifted slightly toward shorter wavelengths with maximum at 420 nm (450 nm for Hamamatsu). The presented measurements cover selection of the SiPM optimum operating voltage (in respect to energy resolution), verification of the excess noise factor and check of the linearity characteristics. Moreover, the gamma spectrometry with LSO, BGO and CsI:Tl scintillators together with pulse characteristics for these crystals (rise time and fall time) is reported, as well as temperature dependence. The presented measurements show better performance of the SensL array comparing to the Hamamatsu detector.

  20. In situ gamma spectrometry measurements and Monte Carlo computations for the detection of radioactive sources in scrap metal.

    PubMed

    Clouvas, A; Xanthos, S; Takoudis, G; Potiriadis, C; Silva, J

    2005-02-01

    A very limited number of field experiments have been performed to assess the relative radiation detection sensitivities of commercially available equipment used to detect radioactive sources in recycled metal scrap. Such experiments require the cooperation and commitment of considerable resources on the part of vendors of the radiation detection systems and the cooperation of a steel mill or scrap processing facility. The results will unavoidably be specific to the equipment tested at the time, the characteristics of the scrap metal involved in the tests, and to the specific configurations of the scrap containers. Given these limitations, the use of computer simulation for this purpose would be a desirable alternative. With this in mind, this study sought to determine whether Monte Carlo simulation of photon flux energy distributions resulting from a radiation source in metal scrap would be realistic. In the present work, experimental and simulated photon flux energy distributions in the outer part of a truck due to the presence of embedded radioactive sources in the scrap metal load are compared. The experimental photon fluxes are deduced by in situ gamma spectrometry measurements with portable Ge detector and the calculated ones by Monte Carlo simulations with the MCNP code. The good agreement between simulated and measured photon flux energy distributions indicate that the results obtained by the Monte Carlo simulations are realistic.

  1. Detection limit calculations for peak evaluation methods in HPGe gamma-ray spectrometry according to ISO 11929

    NASA Astrophysics Data System (ADS)

    Kanisch, Günter

    2017-05-01

    Two peak area estimation methods in gamma-ray spectrometry, the total peak area (TPA) and the background step function (BSF) methods are re-considered first. For least-squares (LS) peak fitting then, a new net peak area uncertainty model is established. It results in a new function fB replacing a TPA method internal design factor. This allows applying the TPA-related decision threshold (DT) and detection limit (DL) formulae, based on ISO 11929(2010), also for peak fitting. Linear LS adapted to Poisson counting data is suggested to derive fB values for a single peak and different combinations of background shape components including a fitted BSF. fB is then adapted to penalized non-linear fitting including Poisson maximum likelihood estimation by MC simulations. Within the DL iteration the fB method is much faster than with non-linear re-fitting. The fitted peak area uncertainty can be safely modeled for peak areas up to 10 DT which is sufficient for DL calculations. The extension for peak multiplets is indicated.

  2. Martian surface heat production and crustal heat flow from Mars Odyssey Gamma-Ray spectrometry

    NASA Astrophysics Data System (ADS)

    Hahn, B. C.; McLennan, S. M.; Klein, E. C.

    2011-07-01

    Martian thermal state and evolution depend principally on the radiogenic heat-producing element (HPE) distributions in the planet's crust and mantle. The Gamma-Ray Spectrometer (GRS) on the 2001 Mars Odyssey spacecraft has mapped the surface abundances of HPEs across Mars. From these data, we produce the first models of global and regional surface heat production and crustal heat flow. As previous studies have suggested that the crust is a repository for approximately 50% of the radiogenic elements on Mars, these models provide important, directly measurable constraints on Martian heat generation. Our calculations show considerable geographic and temporal variations in crustal heat flow, and demonstrate the existence of anomalous heat flow provinces. We calculate a present day average surface heat production of 4.9 ± 0.3 × 10-11 W · kg-1. We also calculate the average crustal component of heat flow of 6.4 ± 0.4 mW · m-2. The crustal component of radiogenically produced heat flow ranges from <1 mW · m-2 in the Hellas Basin and Utopia Planitia regions to ˜13 mW · m-2 in the Sirenum Fossae region. These heat production and crustal heat flow values from geochemical measurements support previous heat flow estimates produced by different methodologies.

  3. Neutron activation analysis, gamma ray spectrometry and radiation environment monitoring instrument concept: GEORAD

    NASA Astrophysics Data System (ADS)

    Ambrosi, R. M.; Talboys, D. L.; Sims, M. R.; Bannister, N. P.; Makarewicz, M.; Stevenson, T.; Hutchinson, I. B.; Watterson, J. I. W.; Lanza, R. C.; Richter, L.; Mills, A.; Fraser, G. W.

    2005-02-01

    Geological processes on Earth can be related to those that may have occurred in past epochs on Mars, if analytical methods used on Earth can be operated remotely on the surface of the Red Planet. Nuclear analytical techniques commonly used in terrestrial geology are neutron activation analysis (NAA) and gamma-ray spectroscopy (GRS), which determine the elemental composition, elemental concentration and stratigraphical distribution of water in rocks and soils. We describe a detector concept called GEORAD (GEOlogical and RADiation environment package) for the proposed ExoMars rover within the ESA's Aurora Programme for the exploration of the Solar System. GEORAD consists of a compact neutron source for the NAA of rocks and soils and a GRS. The GRS has a dual role since it can be used for natural radioactivity studies and NAA. A fully depleted silicon detector coupled to neutron sensitive converters measures the solar particle and neutron flux interacting with the Martian surface. We describe how the GEORAD detector suite could contribute to the geological and biological characterisation of Mars both for the detection of extinct or extant life and to evaluate potential hazards facing future manned missions. We show how GEORAD measurements complement the astrobiological objectives of the Aurora programme.

  4. Depleted uranium in Kosovo: results of a survey by gamma spectrometry on soil samples.

    PubMed

    Uyttenhove, J; Lemmens, M; Zizi, M

    2002-10-01

    The presence of depleted uranium in the soil of former Yugoslavia after the 1999 conflict raised great public concern all over the world. The so-called Balkan-syndrome is often linked with depleted uranium contamination. An excellent compilation of data about DU and its possible impact on health and environment can be found in the 1999 UNEP report and publications from the Swedish Radiation Protection Institute. Unfortunately, very few systematic and reliable data on the possible depleted uranium concentrations were until now available. Some of these rare data are only available on the web, without adequate information about the experimental procedure used. To clarify the situation, a systematic survey was started in the summer of 2000 as a collaborative effort between Ghent University (Physics Laboratory) and the Belgian Ministry of Defense (Medical Service). From 50 sites selected all over Kosovo, 150 soil samples were measured in the laboratory with a high-resolution gamma-spectrometer. Some sites (14) were explicitly selected based on military information on the use of depleted uranium munitions in the vicinity. After careful analysis we can conclude that there is no indication of any depleted uranium contamination on these 50 sites with a minimal detectable activity of 15 Bq; this corresponds approximately to 1 mg depleted uranium in a typical sample (100-150 g).

  5. Reconstruction of distribution functions of fast ions and runaway electrons in fusion plasmas using gamma-ray spectrometry with applications to ITER

    NASA Astrophysics Data System (ADS)

    Shevelev, A. E.; Khilkevitch, E. M.; Kiptily, V. G.; Chugunov, I. N.; Gin, D. B.; Doinikov, D. N.; Naidenov, V. O.; Litvinov, A. E.; Polunovskii, I. A.; Contributors, JET-EFDA

    2013-12-01

    Gamma-ray spectrometry on ITER can provide information both on confined fusion alpha particles for optimization of plasma heating and runaway electrons, which is important for safe reactor operations. For the purpose of deconvolution of gamma-ray spectra recorded in fusion plasma experiments the DeGaSum code has been developed. The code can be applied for processing of both spectra of monoenergetic gamma rays, which are born in nuclear reactions produced by alpha particles and other fast ions, and continuous bremsstrahlung spectra generated by runaway electrons in the MeV range in the plasma and reactor structure materials. Gamma-ray spectrometer response functions and bremsstrahlung spectra generated by electrons in the MeV energy range are calculated and used in the DeGaSum code. The deconvolution of the discrete spectra allows the identification of nuclear reactions, which give rise to gamma rays, and the calculation of their intensities. By applying the code for continuous hard x-ray spectra, the runaway electron energy distribution can be inferred. It can provide the maximal energy of runaway electrons with accuracy, which satisfies the ITER project requirements. The code has been used for processing of spectra recorded in JET experiments. An application of the deconvolution technique for gamma-ray emission measurements on ITER is discussed.

  6. Estimation of the Vertical Distribution of Radiocesium in Soil on the Basis of the Characteristics of Gamma-Ray Spectra Obtained via Aerial Radiation Monitoring Using an Unmanned Helicopter.

    PubMed

    Ochi, Kotaro; Sasaki, Miyuki; Ishida, Mutsushi; Hamamoto, Shoichiro; Nishimura, Taku; Sanada, Yukihisa

    2017-08-17

    After the Fukushima Daiichi Nuclear Power Plant accident, the vertical distribution of radiocesium in soil has been investigated to better understand the behavior of radiocesium in the environment. The typical method used for measuring the vertical distribution of radiocesium is troublesome because it requires collection and measurement of the activity of soil samples. In this study, we established a method of estimating the vertical distribution of radiocesium by focusing on the characteristics of gamma-ray spectra obtained via aerial radiation monitoring using an unmanned helicopter. The estimates are based on actual measurement data collected at an extended farm. In this method, the change in the ratio of direct gamma rays to scattered gamma rays at various depths in the soil was utilized to quantify the vertical distribution of radiocesium. The results show a positive correlation between the abovementioned and the actual vertical distributions of radiocesium measured in the soil samples. A vertical distribution map was created on the basis of this ratio using a simple equation derived from the abovementioned correlation. This technique can provide a novel approach for effective selection of high-priority areas that require decontamination.

  7. Estimation of the Vertical Distribution of Radiocesium in Soil on the Basis of the Characteristics of Gamma-Ray Spectra Obtained via Aerial Radiation Monitoring Using an Unmanned Helicopter

    PubMed Central

    Ochi, Kotaro; Sasaki, Miyuki; Ishida, Mutsushi; Sanada, Yukihisa

    2017-01-01

    After the Fukushima Daiichi Nuclear Power Plant accident, the vertical distribution of radiocesium in soil has been investigated to better understand the behavior of radiocesium in the environment. The typical method used for measuring the vertical distribution of radiocesium is troublesome because it requires collection and measurement of the activity of soil samples. In this study, we established a method of estimating the vertical distribution of radiocesium by focusing on the characteristics of gamma-ray spectra obtained via aerial radiation monitoring using an unmanned helicopter. The estimates are based on actual measurement data collected at an extended farm. In this method, the change in the ratio of direct gamma rays to scattered gamma rays at various depths in the soil was utilized to quantify the vertical distribution of radiocesium. The results show a positive correlation between the abovementioned and the actual vertical distributions of radiocesium measured in the soil samples. A vertical distribution map was created on the basis of this ratio using a simple equation derived from the abovementioned correlation. This technique can provide a novel approach for effective selection of high-priority areas that require decontamination. PMID:28817098

  8. Gamma-ray spectrometry in the field: Radioactive heat production in the Central Slovakian Volcanic Zone

    NASA Astrophysics Data System (ADS)

    Harley, Thomas L.; Westaway, Rob; McCay, Alistair T.

    2017-05-01

    We report 62 sets of measurements from central-southern Slovakia, obtained using a modern portable gamma-ray spectrometer, which reveal the radioactive heat production in intrusive and extrusive igneous rocks of the Late Cenozoic Central Slovakian Volcanic Zone. Sites in granodiorite of the Štiavnica pluton are thus shown to have heat production in the range 2.2-4.9 μW m- 3, this variability being primarily a reflection of variations in content of the trace element uranium. Sites in dioritic parts of this pluton have a lower, but overlapping, range of values, 2.1-4.4 μW m- 3. Sites that have been interpreted in adjoining minor dioritic intrusions of similar age have heat production in the range 1.4-3.3 μW m- 3. The main Štiavnica pluton has zoned composition, with potassium and uranium content and radioactive heat production typically increasing inward from its margins, reflecting variations observed in other granodioritic plutons elsewhere. It is indeed possible that the adjoining dioritic rocks, hitherto assigned to other minor intrusions of similar age, located around the periphery of the Štiavnica pluton, in reality provide further evidence for zonation of the same pluton. The vicinity of this pluton is associated with surface heat flow 40 mW m- 2 above the regional background. On the basis of our heat production measurements, we thus infer that the pluton has a substantial vertical extent, our preferred estimate for the scale depth for its downward decrease in radioactive heat production being 8 km. Nonetheless, this pluton lacks any significant negative Bouguer gravity anomaly. We attribute this to the effect of the surrounding volcanic caldera, filled with relatively low-density lavas, 'masking' the pluton's own gravity anomaly. We envisage that emplacement occurred when the pluton was much hotter, and thus of lower density, than at present, its continued uplift, evident from the local geomorphology, being the isostatic consequence of localized erosion

  9. Implications of Martian Surface Composition Determined by Mars Odyssey Gamma-Ray Spectrometry

    NASA Astrophysics Data System (ADS)

    Taylor, G. J.

    2006-12-01

    The Mars Odyssey spacecraft carries a gamma-ray spectrometer (GRS) that allows measurement of several elements (K, Th, Fe, Si, Al, Ca, Cl, and H) on the surface of Mars. Although its spatial resolution is 500 km, it measures the composition in the upper few tens of centimeters (compared to microns to a few hundred microns for reflectance or emission spectral techniques). GRS provides the first global chemical perspective on the composition of the Martian surface, allowing us to assess the composition of the crust and, with judicious assumptions, the bulk silicate composition of the planet. The data also allow us to identify major geochemical provinces to understand the evolution of the crust and search for the effects of aqueous alteration. GRS data show that the Martian surface is chemically heterogeneous. Elemental concentrations vary across the surface, including variations within high-albedo areas that are presumably covered with dust. Fe concentrations are uniformly high, in accord with the compositions of Martian meteorites and most rock samples analyzed by landed instruments. K/Th is variable, but 95% of the surface has a weight ratio between 3000 and 7000. The mean (5300) is double that in terrestrial crustal rocks and in the bulk silicate Earth. These data indicate that bulk silicate Mars is enriched in moderately volatile elements and in FeO compared to Earth, suggesting that there was not extensive mixing throughout the inner solar system during planetary accretion. Cl varies substantially, with the highest values (0.8 wt%) in the region west of the Tharsis Montes. Surface Types (ST) 1 and 2 (identified from TES spectra) are indistinguishable in Si and Fe concentrations, but ST2 is enriched in K and Th by about 30% relative to ST1 (the K/Th ratio is similar in both regions). The combination of TES and GRS data suggests that ST2 is composed of a different suite of (probably) basaltic rocks than is ST1 and has been weathered. The H2O mass fraction (derived

  10. Applied gamma ray spectrometry and remote sensing in delineation of nepheline syenites in rift tectonic settings

    NASA Astrophysics Data System (ADS)

    Chiwona, Annock Gabriel; Manning, David A. C.; Gaulton, Rachel; Cortes, Joaquin A.

    2017-04-01

    The United Nations (2016) observes that 'Neglected Development Minerals' including industrial minerals such as nepheline syenites have great potential for sustainable development, yet their exploitation has not been equally promoted like high value minerals. Nepheline syenites have great potential as alternative potassium (K) silicate fertiliser, as well as a source of Rare Earths. Demand for K fertiliser keeps rising by 3-3.5% annually (Jena et al., 2014) due to increased need to replace K removal from the soil (Sheldrick et al., 2002). The situation is most critical in Sub-Sahara Africa where nutrient loss due to intensive farming accounts to 22kg N, 2.5 kg P and 15 kg of K per hectare annually (Keeble, 2012). Ironically, Africa with 15% of global population, which is also expected to double by 2040 (Manning, 2015), uses only 1.5% of global K fertiliser. In this study, we use recently acquired countrywide airborne geophysical gamma ray data of Malawi (Bates & Mechennef, 2013) and satellite remote sensing data to identify nepheline syenites, suitable as sources of K silicate fertilizer, in rift tectonic settings. Initial focus was on the East African Rift System (EARS) starting with Malawi. Results from these two techniques are compared with X-ray fluorescence (XRF) geochemical analyses of sample collected from fieldwork in some potential areas of Malawi. With lessons from the Rochagem movement (Theodoro & Leonardos, 2006), identification of novel alternative potash sources in Africa will greatly benefit millions of farmers in developing countries, especially in Sub Sahara Africa where fertiliser costs are very high. Considering that high-resolution airborne geophysical data is not available in many African countries due to high costs associated with data acquisition campaigns, alternative and effective remote sensing approaches for delineating nepheline syenite rocks are necessary. References: [1] Bates M & Mechennef, F (2013) Data Acquisition Report, Sander

  11. NURE aerial gamma-ray and magnetic reconnaissance survey of portions of New Mexico, Arizona and Texas. Volume II. Texas-New Mexico-El Paso NH 13-1 Quadrangle. Final report

    SciTech Connect

    Not Available

    1981-09-01

    The results of a high-sensitivity, aerial gamma-ray spectrometer and magnetometer survey of the El Paso, two degree quadrangle, New Mexico, are presented. Instrumentation and methods are described in Volume I of this final report. The work was done by Carson Helicopters Inc., and Carson Helicopters was assisted in the interpretation by International Exploration, Inc. The work was performed for the US Department of Energy - National Uranium Resource Evaluation (NURE) program. A total of 72 statistically significant eU anomalies were identified in this quadrangle. Of this number 20 were considered to be of sufficient intensity to warrant field investigations, however, many of these anomalies appear to be wholly, or in part, associated with various unconsolidated Quaternary deposits. Only three of the 20 can, with certainty be identified with bedrock; one with a Quaternary flow, one with Cambrian sandstone and one with a Precambrian granite.

  12. Characterization of a gamma-butyrolactone synthetase gene homologue (stcA) involved in bafilomycin production and aerial mycelium formation in Streptomyces sp. SBI034.

    PubMed

    Intra, Bungonsiri; Euanorasetr, Jirayut; Nihira, Takuya; Panbangred, Watanalai

    2016-03-01

    Streptomyces SBI034 produces several bafilomycin derivatives. Its afsA homologue (stcA) and putative γ-butyrolactone receptor gene (stcB) were cloned. Construction of a stcA disruptant (stcA gene knockout) resulted in complete abolishment of all bafilomycin production. Electron microscopic analysis showed a defect of aerial mycelium formation and sporulation in the stcA disruptant. Restoration of all phenotypic defects and bafilomycin production was observed in a stcA complemented strain. Addition of exogenous γ-butyrolactone (GBL) extracted from the culture broth of the wild-type strain could stimulate the aerial mycelium and spore formation of the stcA disruptant. These results suggest that stcA plays a role in GBL-mediated regulation of bafilomycin biosynthesis and morphological development in Streptomyces strain SBI034.

  13. Identifying soil management zones in a sugarcane field using proximal sensed electromagnetic induction and gamma-ray spectrometry data

    NASA Astrophysics Data System (ADS)

    Dennerley, Claire; Huang, Jingyi; Nielson, Rod; Sefton, Michael; Triantafilis, John

    2017-04-01

    Over 70% of the Australian sugarcane industry operates in alluvial-estuarine areas characterised by sodic and infertile soils. There is a need to supply ameliorants and improve fertilisers and minimise off-farm pollution to the Great Barrier Reef. Therefore, information is required about the spatial variation in soils. However, traditional approaches are cost-prohibitive. Herein we showed how a digital soil mapping (DSM) approach can be used to identify soil management zones. In the first instance, ancillary data, including electromagnetic induction and gamma-ray spectrometry data were collected. Using a fuzzy k-means clustering algorithm management zones from two to six were identified. Using restricted maximum likelihood (REML) analysis of various topsoil (0-0.3m) and subsoil (0.6-0.9m) physical (e.g. clay) and chemical (e.g. exchangeable sodium percentage [ESP], exchangeable calcium and magnesium) properties, 3 zones were determined from minimising the mean squared prediction error. To manage the moderately sodic topsoil ESP of zones 3A and 3C and sodic 3B, different gypsum requirements were prescribed. Lime can also be added differentially to address low exchangeable Ca in zone 3A, 3B and 3C. With regard to exchangeable Mg, zones 3A and 3C do not require any fertiliser, whereas zone 3A requires the addition of a moderate amount. The results were consistent with percentage yield variance, suggesting the lower yield in 3C due to topsoil sodicity and strongly sodic subsoil with higher clay content. We concluded that the DSM approach was successful in identifying soil management zones and can be used to improve structural stability and soil fertility.

  14. Improvements on Low Level Activity Gamma Measurements and X-ray Spectrometry at the CEA-MADERE Measurement Platform

    NASA Astrophysics Data System (ADS)

    Sergeyeva, Victoria; Domergue, Christophe; Destouches, Christophe; Girard, Jean Michel; Philibert, Hervé; Bonora, Jonathan; Thiollay, Nicolas; Lyoussi, Abdallah

    2016-02-01

    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 continuous improvement process. Recently, two High Efficiency diodes have been integrated to the MADERE platform in order to manage the accurate low level activity measurements (few Bq per sample). This new equipment provides a good level of efficiency over the energy range from 60 keV to 2 MeV. The background continuum is reduced due to the use of a Ultra Low Background (ULB) lead shielding. Relative and absolute X-ray measurement techniques have been improved in order to facilitate absolute rhodium activity measurement (Rh103m) on solid samples. Additional efforts have been made to increase the accuracy of the relative niobium (Nb93m) activity measurement technique. The way of setting up an absolute measurement method for niobium is under investigation. After a presentation of the MADERE's measurement devices, this paper focuses on the technological options taken into account for the design of high efficiency measurement devices. Then, studies performed on X-ray measurement techniques are presented. Some details about the calculation of uncertainties and correction factors are also mentioned. Finally, future research and development axes are exposed.

  15. Aerial Photography

    NASA Technical Reports Server (NTRS)

    1985-01-01

    John Hill, a pilot and commercial aerial photographer, needed an information base. He consulted NERAC and requested a search of the latest developments in camera optics. NERAC provided information; Hill contacted the manufacturers of camera equipment and reduced his photographic costs significantly.

  16. Development and calibration of a real-time airborne radioactivity monitor using direct gamma-ray spectrometry with two scintillation detectors.

    PubMed

    Casanovas, R; Morant, J J; Salvadó, M

    2014-07-01

    The implementation of in-situ gamma-ray spectrometry in an automatic real-time environmental radiation surveillance network can help to identify and characterize abnormal radioactivity increases quickly. For this reason, a Real-time Airborne Radioactivity Monitor using direct gamma-ray spectrometry with two scintillation detectors (RARM-D2) was developed. The two scintillation detectors in the RARM-D2 are strategically shielded with Pb to permit the separate measurement of the airborne isotopes with respect to the deposited isotopes.In this paper, we describe the main aspects of the development and calibration of the RARM-D2 when using NaI(Tl) or LaBr3(Ce) detectors. The calibration of the monitor was performed experimentally with the exception of the efficiency curve, which was set using Monte Carlo (MC) simulations with the EGS5 code system. Prior to setting the efficiency curve, the effect of the radioactive source term size on the efficiency calculations was studied for the gamma-rays from (137)Cs. Finally, to study the measurement capabilities of the RARM-D2, the minimum detectable activity concentrations for (131)I and (137)Cs were calculated for typical spectra at different integration times. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Profiles of gamma-ray and magnetic data for aerial surveys over parts of the Western United States from longitude 108 to 126 degrees W. and from latitude 34 to 49 degrees N.

    USGS Publications Warehouse

    Duval, Joseph S.

    1995-01-01

    This CD-ROM contains images generated from geophysical data, software for displaying and analyzing the images and software for displaying and examining profile data from aerial surveys flown as part of the National Uranium Resource Evaluation (NURE) Program of the U.S. Department of Energy. The images included are of gamma-ray data (uranium, thorium, and potassium channels), Bouguer gravity data, isostatic residual gravity data, aeromagnetic anomalies, topography, and topography with bathymetry. This publication contains image data for the conterminous United States and profile data for the conterminous United States within the area longitude 108 to 126 degrees W. and latitude 34 to 49 degrees N. The profile data include apparent surface concentrations of potassium, uranium, and thorium, the residual magnetic field, and the height above the ground. The images on this CD-ROM include graytone and color images of each data set, color shaded-relief images of the potential-field and topographic data, and color composite images of the gamma-ray data. The image display and analysis software can register images with geographic and geologic overlays. The profile display software permits the user to view the profiles as well as obtain data listings and export ASCII versions of data for selected flight lines.

  18. Measurement of {sup 25}Mg(p, {gamma}){sup 26}Al{sup g} resonance strengths via accelerator mass spectrometry

    SciTech Connect

    Arazi, A.; Niello, J. O. Fernandez; Faestermann, T.; Knie, K.; Korschinek, G.; Poutivtsev, M.; Rugel, G.; Richter, E.; Wallner, A.

    2006-08-15

    The strengths of resonances located at center-of-mass energies of E{sub c.m.}=189, 304, 374, and 418 keV for the {sup 25}Mg(p,{gamma}) reaction have been measured for the first time with an off-line method: Mg targets were firstly activated with protons at the resonance energies and the produced {sup 26}Al{sup g} nuclei were counted by means of highly sensitive accelerator mass spectrometry (AMS). Thus, the production of {sup 26}Al in its ground state is determined independently from the {gamma}-decay branching ratio. While the 304, 374, and 418 keV resonances show fair agreement with previous measurements, the 189 keV resonance yield a significantly less strength. In addition, an experimental upper limit for the E{sub c.m.}=92 keV resonance was determined.

  19. Gamma-ray spectrometry method used for radioactive waste drums characterization for final disposal at National Repository for Low and Intermediate Radioactive Waste--Baita, Romania.

    PubMed

    Done, L; Tugulan, L C; Dragolici, F; Alexandru, C

    2014-05-01

    The Radioactive Waste Management Department from IFIN-HH, Bucharest, performs the conditioning of the institutional radioactive waste in concrete matrix, in 200 l drums with concrete shield, for final disposal at DNDR - Baita, Bihor county, in an old exhausted uranium mine. This paper presents a gamma-ray spectrometry method for the characterization of the radioactive waste drums' radionuclides content, for final disposal. In order to study the accuracy of the method, a similar concrete matrix with Portland cement in a 200 l drum was used. © 2013 The Authors. Published by Elsevier Ltd All rights reserved.

  20. Low-resolution gamma-ray spectrometry for an information barrier based on a multi-criteria template-matching approach

    NASA Astrophysics Data System (ADS)

    Göttsche, Malte; Schirm, Janet; Glaser, Alexander

    2016-12-01

    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.

  1. On background radiation gradients--the use of airborne surveys when searching for orphan sources using mobile gamma-ray spectrometry.

    PubMed

    Kock, Peder; Rääf, Christopher; Samuelsson, Christer

    2014-02-01

    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.

  2. Construction and testing of a neutron and gamma spectrometry system using pulse shape discrimination with an organic scintillator

    NASA Astrophysics Data System (ADS)

    Pope, Robert S.

    1993-03-01

    The goal of this thesis was to construct and test a neutron detector to measure the energy spectrum of 1 to 14-MeV neutrons in the presence of gammas. A spectrometer based on the process of pulse shape discrimination (PSD) was constructed, in which the scintillator NE-213 was used. The primary neutron/gamma sources used were 78-mCi and 4.7-Ci Pu-239Be sources, while 4.7-micro-Ci and 97.6-micro-Ci Na-22 gamma sources were used for energy calibration and additional testing of the detector. Proton recoil spectra and Compton electron spectra were unfolded with the neutron and gamma unfolding code FORIST to generate the incident neutron and gamma spectra, respectively. FORIST, which was written for a CDC computer, was modified to run on a VAX 6420. The experimental spectra were compared to those in the literature. The locations of the peaks in the Pu-239Be spectrum agreed with the literature to within 8.3%, the Pu-239Be gamma spectrum agreed to within 0.7%, while the Na-22 gamma spectrum agreed exactly. Uncertainties in the detection system and unfolding procedure are on the order of 5-10%. This thesis is intended to be a summary of the relevant literature and a user's guide to the PSD spectrometer.

  3. Calculation spreadsheet for uncertainty estimation of measurement results in gamma-ray spectrometry and its validation for quality assurance purpose.

    PubMed

    Ceccatelli, Alessia; Dybdal, Ashild; Fajgelj, Ales; Pitois, Aurelien

    2017-03-03

    An Excel calculation spreadsheet has been developed to estimate the uncertainty of measurement results in γ-ray spectrometry. It considers all relevant uncertainty components and calculates the combined standard uncertainty of the measurement result. The calculation spreadsheet has been validated using two independent open access software and is available for download free of charge at: https://nucleus.iaea.org/rpst/ReferenceProducts/Analytical_Methods/index.htm. It provides a simple and easy-to-use template for estimating the uncertainty of γ-ray spectrometry measurement results and supports the radioanalytical laboratories seeking accreditation for their measurements using γ-ray spectrometry.

  4. Favourable uranium-phosphate exploration trends guided by the application of statistical factor analysis technique on the aerial gamma spectrometric data in Syrian desert (Area-1), Syria

    NASA Astrophysics Data System (ADS)

    Asfahani, J.; Al-Hent, R.; Aissa, M.

    2016-02-01

    A scored lithological map including 10 radiometric units is established through applying factor analysis approach to aerial spectrometric data of Area-1, Syrian desert, which includes Ur, eU, eTh, K%, eU/eTh, eU/K%, and eTh/K%. A model of four rotated factors F1, F2, F3, and F4 is adapted for representing 234,829 data measured points in Area-1, where 86% of total data variance is interpreted. A geological scored pseudo-section derived from the lithological scored map is established and analyzed in order to show the possible stratigraphic and structural traps for uranium occurrences associated with phosphate deposits in the studied Area-1. These identified traps presented in this paper need detailed investigation and must be necessarily followed and checked by ground validations and subsurface well logging, in order to locate the anomalous uranium occurrences and explore with more confidence and certitude their characteristics as a function of depth.

  5. Spectral interference corrections for the measurement of (238)U in materials rich in thorium by a high resolution gamma-ray spectrometry.

    PubMed

    Yücel, H; Solmaz, A N; Köse, E; Bor, D

    2009-11-01

    In this study, the spectral interferences are investigated for the analytical peaks at 63.3 keV of (234)Th and 1001.0 keV of (234m)Pa, which are often used in the measurement of (238)U activity by the gamma-ray spectrometry. The correction methods are suggested to estimate the net peak areas of the gamma-rays overlapping the analytical peaks, due to the contribution of (232)Th that may not be negligible in materials rich in natural thorium. The activity results for the certified reference materials (CRMs) containing U and Th were measured with a well type Ge detector. The self-absorption and true coincidence-summing (TCS) effects were also taken into account in the measurements. It is found that ignoring the contributions of the interference gamma-rays of (232)Th and (235)U to the mixed peak at 63.3 keV of (234)Th ((238)U) leads to the remarkably large systematic influence of 0.8-122% in the measured (238)U activity, but in case of ignoring the contribution of (232)Th via the interference gamma-ray at 1000.7 keV of (228)Ac to the mixed peak at 1001 keV of (234m)Pa ((238)U) results in relatively smaller systematic influence of 0.05-3%, depending on thorium contents in the samples. The present results showed that the necessary correction for the spectral interferences besides self-absorption and TCS effects is also very important to obtain more accurate (238)U activity results. Additionally, if one ignores the contribution of (232)Th to both (238)U and (40)K activities in materials, the maximum systematic influence on the effective radiation dose is estimated to be ~6% and ~1% via the analytical peaks at 63.3 and 1001 keV for measurement of the (238)U activity, respectively.

  6. Comparison of optimised germanium gamma spectrometry and multicollector inductively coupled plasma mass spectrometry for the determination of 134Cs, 137Cs and 154Eu single ratios in highly burnt UO 2

    NASA Astrophysics Data System (ADS)

    Caruso, S.; Günther-Leopold, I.; Murphy, M. F.; Jatuff, F.; Chawla, R.

    2008-05-01

    Non-destructive and destructive methods have been compared to validate their corresponding assessed accuracies in the measurement of 134Cs/137Cs and 154Eu/137Cs isotopic concentration ratios in four spent UO2 fuel samples with very high (52 and 71 GWd/t) and ultra-high (91 and 126 GWd/t) burnup values, and about 10 (in the first three samples) and 4 years (in the latter sample) cooling time. The non-destructive technique tested was high-resolution gamma spectrometry using a high-purity germanium detector (HPGe) and a special tomographic station for the handling of highly radioactive 400 mm spent fuel segments that included a tungsten collimator, lead filter (to enhance the signal to Compton background ratio and reduce the dead time) and paraffin wax (to reduce neutron damage). The non-destructive determination of these isotopic concentration ratios has been particularly challenging for these segments because of the need to properly derive non-Gaussian gamma-peak areas and subtract the background from perturbing capture gammas produced by the intrinsic high-intensity neutron emissions from the spent fuel. Additionally, the activity distribution within each pin was determined tomographically to correct appropriately for self-attenuation and geometrical effects. The ratios obtained non-destructively showed a 1σ statistical error in the range 1.9-2.9%. The destructive technique used was a high-performance liquid chromatographic separation system, combined online to a multicollector inductively coupled plasma mass spectrometer (HPLC-MC-ICP-MS), for the analysis of dissolved fuel solutions. During the mass spectrometric analyses, special care was taken in the optimisation of the chromatographic separation for Eu and the interfering element Gd, as also in the mathematical correction of the 154Gd background from the 154Eu signal. The ratios obtained destructively are considerably more precise (1σ statistical error in the range 0.4-0.8% for most of the samples, but up to

  7. Development and validation of a high-throughput based on liquid chromatography with ultraviolet absorption and mass spectrometry detection method for quantitation of cichoric acid in Echinacea purpurea aerial-based dietary supplements.

    PubMed

    Chen, Pei

    2006-01-01

    A new, rapid, and reproducible reversed-phased liquid chromatography (LC) method with ultraviolet (UV) absorption and/or mass spectrometry (MS) detection has been developed and validated for quantitation of cichoric acid, a major constituent of Echinacea spp. The method involves the use of a short Phenomenex Hydro-RP C18 column (4 microm, 50 mm x 3.0 mm id) and a simple isocratic mobile phase profile. Both UV (diode array detector) and selective-ion monitoring (SIM) at m/z 472.8 were used for quantitation of cichoric acid. The limit of detection was 0.75 ng for UV and 0.15 ng for MS-SIM, and the limit of quantitation was is 2.5 ng for UV and 0.5 ng for MS-SIM. Water-methanol (1 + 1) soluble extracts of 6 commercially available Echinacea purpurea aerial parts-based dietary supplements (EPADS). EPADS were first profiled using a traditional HPLC-UV method. Their UV chromatograms were compared, and cichoric acid was identified to be a key biomarker for EPADS. Then the samples were analyzed by the fast LC-UV/MS method. The turnaround time for a single analysis was 3 min, compared to 15 to 60 min needed for traditional reported LC methods. The high-throughput method was able to separate the cichoric acid peak from peaks of other components in extracts of complex matrixes of EPADS.

  8. Analysis by gas chromatography-mass spectrometry of the essential oils from the aerial parts of Pimpinella anagodendron Bolle and Pimpinella rupicola Svent., two endemic species to the Canary Islands, Spain.

    PubMed

    Velasco-Negueruela, A; Pérez-Alonso, M J; de Paz, P L Pérez; Palá-Paúl, J; Sanz, J

    2005-11-18

    The essential oils from the aerial parts of Pimpinella anagodendron Bolle and Pimpinella rupicola Svent., two endemic species growing in Tenerife, Canary Islands, Spain, were studied by gas chromatography and gas chromatography-mass spectrometry. The major components of the flowering tops (flowers+unripe fruits) of P. rupicola (PRFT) were found to be beta-bisabolene (34.8%), limonene (10.9%) and alpha-zingiberene (10.5%), whereas in the flowering tops of P. anagodendron (PAFT), the main constituents were alpha-zingiberene (32.9%), beta-bisabolene (17.9%), beta-pinene (15.8%) and ar-curcumene (11.5%). The major compounds found in the stems+leaves of P. rupicola (PRSL) were beta-bisabolene (31.6%), alpha-zingiberene (11.4%) and limonene (10.8%), whereas those of P. anagodendron (PASL) were alpha-zingiberene (32.3%), beta-bisabolene (14.0%) and ar-curcumene (12.6%). In all the oils were found the characteristic constituents of genus Pimpinella, the pseudoisoeugenol esters. In accordance with the morphological, chorological and chemical differences between both species, we suggest that P. rupicola Svent. is a good taxon and not a synonym of P. anagodendron.

  9. Intercomparison of inductively coupled plasma mass spectrometry, quantitative neutron capture radiography, and prompt gamma activation analysis for the determination of boron in biological samples.

    PubMed

    Schütz, C L; Brochhausen, C; Hampel, G; Iffland, D; Kuczewski, B; Otto, G; Schmitz, T; Stieghorst, C; Kratz, J V

    2012-10-01

    Boron determination in blood and tissue samples is a crucial task especially for treatment planning, preclinical research, and clinical application of boron neutron capture therapy (BNCT). Comparison of clinical findings remains difficult due to a variety of analytical methods, protocols, and standard reference materials in use. This paper addresses the comparability of inductively coupled plasma mass spectrometry, quantitative neutron capture radiography, and prompt gamma activation analysis for the determination of boron in biological samples. It was possible to demonstrate that three different methods relying on three different principles of sample preparation and boron detection can be validated against each other and yield consistent results for both blood and tissue samples. The samples were obtained during a clinical study for the application of BNCT for liver malignancies and therefore represent a realistic situation for boron analysis.

  10. Thermal neutron fluence from ultra low-level gamma-ray spectrometry of spoons activated during the JCO criticality accident at Tokai-mura in 1999.

    PubMed

    Hult, Mikael; Martínez Canet, María Jose; Johnston, Peter N; Komura, Kazuhisa

    2002-01-01

    During the JCO-accident in Tokai-mura in 1999, the surrounding village was irradiated by an uncontrolled neutron flux. At some locations in that village, the thermal neutron flux was determined retrospectively by measurement of the very low activity of 51Cr and 60Co in stainless-steel spoons using gamma-ray spectrometry in underground laboratories. Activities determined in the HADES underground facility are presented here, together with calibrations performed using a well-defined thermal neutron flux to directly estimate the fluence of thermal neutrons independent of most assumptions. The results show measurable 51Cr in three samples and 60Co in four samples taken from locations at distances of up to 430m from the accident location despite the elapse of 4 half-lives of 51Cr before measurement. Effects of air transport of the samples were considered and shown to be negligible.

  11. Determination of thorium-232 in Canadian soils by gamma-ray spectrometry via lead-212 and actinium-228, interference from uranium

    SciTech Connect

    Zikovsky, L.; Blagoeva, R.

    1994-12-31

    Thorium-232 background levels in non-cultivated Canadian soils (southern and northern Quebec and the Northwest Territories) are presented. Gamma-ray spectrometry was used to determine the activity of {sup 232}Th by measuring the activities of {sup 228}Ac and {sup 212}Pb at 37 sites. The specific activity levels ranged from 2.7 to 95.5 Bq/kg with an overall mean of 24.0 {+-} 15.4 Bq/kg. This activity generated an annual absorbed dose equivalent in air of 0.1 mSv. The activities of {sup 228}Ac and {sup 212}Pb in the soil increased with increasing depth. IT was found that uranium, via its decay product radium, can interfere with the determination of thorium in the soil.

  12. Radon potential mapping of the Tralee-Castleisland and Cavan areas (Ireland) based on airborne gamma-ray spectrometry and geology.

    PubMed

    Appleton, J D; Doyle, E; Fenton, D; Organo, C

    2011-06-01

    The probability of homes in Ireland having high indoor radon concentrations is estimated on the basis of known in-house radon measurements averaged over 10 km × 10 km grid squares. The scope for using airborne gamma-ray spectrometer data for the Tralee-Castleisland area of county Kerry and county Cavan to predict the radon potential (RP) in two distinct areas of Ireland is evaluated in this study. Airborne data are compared statistically with in-house radon measurements in conjunction with geological and ground permeability data to establish linear regression models and produce radon potential maps. The best agreement between the percentage of dwellings exceeding the reference level (RL) for radon concentrations in Ireland (% > RL), estimated from indoor radon data, and modelled RP in the Tralee-Castleisland area is produced using models based on airborne gamma-ray spectrometry equivalent uranium (eU) and ground permeability data. Good agreement was obtained between the % > RL from indoor radon data and RP estimated from eU data in the Cavan area using terrain specific models. In both areas, RP maps derived from eU data are spatially more detailed than the published 10 km grid map. The results show the potential for using airborne radiometric data for producing RP maps.

  13. Analysis of gamma-irradiated melon, pumpkin, and sunflower seeds by electron paramagnetic resonance spectroscopy and gas chromatography-mass spectrometry.

    PubMed

    Sin, Della W M; Wong, Yiu Chung; Yao, Wai Yin

    2006-09-20

    Seeds of melon (Citrullus lanatus var. sp.), pumpkin (Cucurbita moschata), and sunflower (Heliantus annus) were gamma-irradiated at 1, 3, 5, and 10 kGy and analyzed by electron paramagnetic resonance (EPR) and gas chromatography-mass spectrometry (GC-MS) according to EN1787:2000 and EN1785:2003, respectively. Distinguishable triplet signals due to the presence of induced cellulose radicals were found at 2.0010-2.0047 g in the EPR spectra. The gamma-irradiated radiolytic markers of 2-dodecylcyclobutanone (2-DCB) and 2-tetradecylcyclobutanone (2-TCB) were identified in all irradiated seed samples. Both the free radicals and the alkylcyclobutanones were found to increase with irradiation dose. In general, linear relationships between the amount of radicals and irradiation dosage could be established. Studies at an ambient temperature (20-25 degrees C) in a humidity-controlled environment showed a complete disappearance of the cellulosic peaks for irradiated samples upon 60 days of storage. Such instability behavior was considered to render the usefulness of using EPR alone in the determination of irradiated seed samples. On the other hand, 2-DCB and 2-TCB were also found to decompose rapidly (>85% loss after 120 days of storage), but the radiolytic markers remained quantifiable after 120 days of postirradiation storage. These results suggest that GC-MS is a versatile and complimentary technique for the confirmation of irradiation treatment to seeds.

  14. Performance of cerium-doped Gd3Al2Ga3O12 (GAGG:Ce) scintillator in gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    Iwanowska, Joanna; Swiderski, Lukasz; Szczesniak, Tomasz; Sibczynski, Pawel; Moszynski, Marek; Grodzicka, Martyna; Kamada, Kei; Tsutsumi, Kousuke; Usuki, Yoshiyuki; Yanagida, Takayuki; Yoshikawa, Akira

    2013-06-01

    Performance of cerium-doped Gd3Al2Ga3O12 (GAGG:Ce) scintillator in gamma-ray spectrometry has been investigated. The measurements of two samples of GAGG:Ce cover the tests of emission spectra (maximum of emission at about 530 nm), light output, non-proportionality, energy resolution, time resolution and decay time of light pulses. We compare the results with commonly known scintillators, such as NaI(Tl), LSO, LuAG etc. The results show that GAGG:Ce has a high light yield of about 33000 ph/MeV as measured with Hamamatsu S3590-18 Si PiN photodiode [1]. The total energy resolution for 662 keV gamma-rays from 137Cs source is equal to about 6%, whereas intrinsic resolution is equal to 5.2%. Additionally, we made basic measurements of photoelectron yield, non-proportionality and total energy resolution of small sample (5×5×5 mm3) of GAGG:Ce crystal coupled to Hamamatsu MPPC array (6×6 mm2). The results show that the performance of GAGG:Ce measured with the MPPC array are similar to those measured with the PMT.

  15. Determination of (241)Pu by the method of disturbed radioactive equilibrium using 2πα-counting and precision gamma-spectrometry.

    PubMed

    Alekseev, I; Kuzmina, T

    2016-04-01

    A simple technique is proposed for the determination of the content of (241)Pu, which is based on disturbance of radioactive equilibrium in the genetically related (237)U←(241)Pu→(241)Am decay chain of radionuclides, with the subsequent use of 2πα-counting and precision gamma-spectroscopy for monitoring the process of restoration of that equilibrium. It has been shown that the data on dynamics of accumulation of the daughter (241)Am, which were obtained from the results of measurements of α- and γ-spectra of the samples, correspond to the estimates calculated for the chain of two genetically related radionuclides, the differences in the estimates of (241)Pu radioactivity not exceeding 2%. Combining the different methods of registration (2πα-counting, semiconductor alpha- and gamma-spectrometry) enables the proposed method to be efficiently applied both for calibration of (241)Pu-sources (from several hundreds of kBq and higher) and for radioisotopic analysis of plutonium mixtures. In doing so, there is a deep purification of (241)Pu from its daughter decay products required due to unavailability of commercial detectors that could make it possible, based only on analysis of alpha-spectra, to conduct quantitative analysis of the content of (238)Pu and (241)Am. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Carbon isotopic ratio analysis by gas chromatography/combustion/isotope ratio mass spectrometry for the detection of gamma-hydroxybutyric acid (GHB) administration to humans.

    PubMed

    Saudan, Christophe; Augsburger, Marc; Mangin, Patrice; Saugy, Martial

    2007-01-01

    Since GHB (gamma-hydroxybutyric acid) is naturally produced in the human body, clinical and forensic toxicologists must be able to discriminate between endogenous levels and a concentration resulting from exposure. To suggest an alternative to the use of interpretative concentration cut-offs, the detection of exogenous GHB in urine specimens was investigated by means of gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). GHB was isolated from urinary matrix by successive purification on Oasis MCX and Bond Elute SAX solid-phase extraction (SPE) cartridges prior to high-performance liquid chromatography (HPLC) fractioning using an Atlantis dC18 column eluted with a mixture of formic acid and methanol. Subsequent intramolecular esterification of GHB leading to the formation of gamma-butyrolactone (GBL) was carried out to avoid introduction of additional carbon atoms for carbon isotopic ratio analysis. A precision of 0.3 per thousand was determined using this IRMS method for samples at GHB concentrations of 10 mg/L. The (13)C/(12)C ratios of GHB in samples of subjects exposed to the drug ranged from -32.1 to -42.1 per thousand, whereas the results obtained for samples containing GHB of endogenous origin at concentration levels less than 10 mg/L were in the range -23.5 to -27.0 per thousand. Therefore, these preliminary results show that a possible discrimination between endogenous and exogenous GHB can be made using carbon isotopic ratio analyses.

  17. Nondestructive and quantitative characterization of TRU and LLW mixed-waste using active and passive gamma-ray spectrometry and computed tomography

    SciTech Connect

    Camp, D.C.; Martz, H.E.

    1991-11-12

    The technology being proposed by LLNL is an Active and Passive Computed Tomography (A P CT) Drum Scanner for contact-handled (CH) wastes. It combines the advantages offered by two well-developed nondestructive assay technologies: gamma-ray spectrometry and computed tomography (CT). Coupled together, these two technologies offer to nondestructively and quantitatively characterize mixed- wastes forms. Gamma-ray spectroscopy uses one or more external radiation detectors to passively and nondestructively measure the energy spectrum emitted from a closed container. From the resulting spectrum one can identify most radioactivities detected, be they transuranic isotopes, mixed-fission products, activation products or environmental radioactivities. Spectral libraries exist at LLNL for all four. Active (A) or transmission CT is a well-developed, nondestructive medical and industrial technique that uses an external-radiation beam to map regions of varying attenuation within a container. Passive (P) or emission CT is a technique mainly developed for medical application, e.g., single-photon emission CT. Nondestructive industrial uses of PCT are under development and just coming into use. This report discuses work on the A P CT Drum Scanner at LLNL.

  18. Identification of surfactins and iturins produced by potent fungal antagonist, Bacillus subtilis K1 isolated from aerial roots of banyan (Ficus benghalensis) tree using mass spectrometry.

    PubMed

    Pathak, Khyati V; Keharia, Hareshkumar

    2014-06-01

    The banyan endophyte, Bacillus subtilis K1, produces a complex mixture of lipopeptides exhibiting potent antifungal activity. These lipopeptides were purified by high-performance liquid chromatography and analyzed using MALDI-TOF-MS as well as liquid chromatography coupled with ESI-MS. A heterogenous mixture of lipopeptides belonging to three different families of cyclic lipopeptides, viz., fengycins, iturins and surfactins, was detected in the cell-free extracellular extract of B. subtilis K1. The detailed mass spectrometric characterization revealed the presence of four variants of iturin A and three variants of iturin C varying in the β-amino fatty acid chain length from C13 to C17. The MS/MS of monovalent alkali metal ion adducts (Na and K) of iturin suggested the Glu(4) as a binding site for metal ion. The LC-ESI-MS/MS analysis of surfactins enabled the identification of seven surfactin variants with the variations in Val/Ile/Leu at position 4 and C13-C17 β-hydroxy fatty acids. This study demonstrates the application of tandem mass spectrometry in identification of closely related lipopeptides from a heterogenous mixture obtained from a natural source. Furthermore, this is the first report of an endophytic bacillus strain co-producing so many variants of surfactins and iturins.

  19. Mapping the spatial distribution and activity of (226)Ra at legacy sites through Machine Learning interpretation of gamma-ray spectrometry data.

    PubMed

    Varley, Adam; Tyler, Andrew; Smith, Leslie; Dale, Paul; Davies, Mike

    2016-03-01

    Radium ((226)Ra) contamination derived from military, industrial, and pharmaceutical products can be found at a number of historical sites across the world posing a risk to human health. The analysis of spectral data derived using gamma-ray spectrometry can offer a powerful tool to rapidly estimate and map the activity, depth, and lateral distribution of (226)Ra contamination covering an extensive area. Subsequently, reliable risk assessments can be developed for individual sites in a fraction of the timeframe compared to traditional labour-intensive sampling techniques: for example soil coring. However, local heterogeneity of the natural background, statistical counting uncertainty, and non-linear source response are confounding problems associated with gamma-ray spectral analysis. This is particularly challenging, when attempting to deal with enhanced concentrations of a naturally occurring radionuclide such as (226)Ra. As a result, conventional surveys tend to attribute the highest activities to the largest total signal received by a detector (Gross counts): an assumption that tends to neglect higher activities at depth. To overcome these limitations, a methodology was developed making use of Monte Carlo simulations, Principal Component Analysis and Machine Learning based algorithms to derive depth and activity estimates for (226)Ra contamination. The approach was applied on spectra taken using two gamma-ray detectors (Lanthanum Bromide and Sodium Iodide), with the aim of identifying an optimised combination of detector and spectral processing routine. It was confirmed that, through a combination of Neural Networks and Lanthanum Bromide, the most accurate depth and activity estimates could be found. The advantage of the method was demonstrated by mapping depth and activity estimates at a case study site in Scotland. There the method identified significantly higher activity (<3 Bq g(-1)) occurring at depth (>0.4m), that conventional gross counting algorithms

  20. Depth profiling of Pu, 241Am and 137Cs in soils from southern Belarus measured by ICP-MS and alpha and gamma spectrometry.

    PubMed

    Boulyga, Sergei F; Zoriy, Myroslav; Ketterer, Michael E; Becker, J Sabine

    2003-08-01

    The depth distribution of plutonium, americium, and 137Cs originating from the 1986 accident at the Chernobyl Nuclear Power Plant (NPP) was investigated in several soil profiles in the vicinity from Belarus. The vertical migration of transuranic elements in soils typical of the 30 km relocation area around Chernobyl NPP was studied using inductively coupled plasma mass spectrometry (ICP-MS), alpha spectrometry, and gamma spectrometry. Transuranic concentrations in upper soil layers ranged from 6 x 10(-12) g g(-1) to 6 x 10(-10) g g(-1) for plutonium and from 1.8 x 10(-13) g g(-1) to 1.6 x 10(-11) g g(-1) for americium. These concentrations correspond to specific activities of (239+240)Pu of 24-2400 Bq kg(-1) and specific activity of 241Am of 23-2000 Bq kg(-1), respectively. Transuranics in turf-podzol soil migrate slowly to the deeper soil layers, thus, 80-95%, of radionuclide inventories were present in the 0-3 cm intervals of turf-podzol soils collected in 1994. In peat-marsh soil migration processes occur more rapidly than in turf-podzol and the maximum concentrations are found beneath the soil surface (down to 3-6 cm). The depth distributions of Pu and Am are essentially identical for a given soil profile. (239+240)Pu/137Cs and 241Am/137Cs activity ratios vary by up to a factor of 5 at some sites while smaller variations in these ratios were observed at a site close to Chernobyl, suggesting that 137Cs is dominantly particle associated close to Chernobyl but volatile species of 137Cs are of relatively greater importance at the distant sites.

  1. Use of airborne gamma-ray spectrometry for environmental assessment of the rehabilitated nabarlek uranium mine, Australia.

    PubMed

    Martin, Paul; Tims, Stephen; McGill, Anthony; Ryan, Bruce; Pfitzner, Kirrilly

    2006-04-01

    This article describes an airborne gamma survey of a 7 x 5 km region around the rehabilitated Nabarlek uranium mine in northern Australia. An unusually tight line spacing (100 m) and low aircraft height (50 m) were used, enabling the survey to distinguish man-made structures such as ponds and accommodation areas, as well as creek lines. Positive correlations between airborne data and ground-based readings enabled an estimation of the average absorbed dose rate arising from terrestrial gamma radiation over large areas of the site to be derived. For the fenced minesite area this estimate was 0.31 micro Gy hr(- 1). The airborne survey data were found to be invaluable in helping to plan further ground-level investigations and showed promise as an assessment tool for rehabilitated minesites.

  2. Interpretation of Gravity and Gamma-Ray Spectrometry Data in Low Temperature Hydrothermal Systems, Southeastern Part of Fukuoka, Japan

    NASA Astrophysics Data System (ADS)

    Nishijima, Jun; Fujimitsu, Yasuhiro

    2016-12-01

    The Hakata hot springs area is located in Fukuoka City, which is in the southwestern part of Japan. Gamma-ray and gravity surveys were conducted to understand the relationship between the low-temperature hydrothermal systems and geophysical data of the area. The depth of the reservoir basement, which was derived from gravity data, gradually deepens toward the east; it includes some steep depth gradients in the Hakata hot springs area. High intensities of gamma-rays were detected around these gradients. In addition, higher hot spring temperatures and flow rates can be observed in this area. These results indicate that some part of the level of the basement where the hot springs are concentrated is a part of the Kego Fault and is similar to the fracture zone created by past activities of the fault. Moreover, these steep depth gradients act as a path for hot spring water from the deeper side of the granitic body to the surface.

  3. Gamma-ray spectrometry: a new tool for exploring archaeological sites; a case study from East Sinai, Egypt

    NASA Astrophysics Data System (ADS)

    Moussa, Mohamed

    2001-10-01

    In geophysical literature the application of gamma-ray spectrometric (GRS) methods in archaeological exploration is not known. This paper demonstrates the applicability of the GRS technique to archaeological exploration. The study was conducted in the Tell Abu Seef area, which is located ˜6 km from El-Qantara city, Egypt where some buried walls (of possible archaeological interest) were detected in 1981. The recorded K% values as well as the readings of total gamma-ray intensities were related to two different radiometric areas that match the building remains and the surrounding sediments. The highest concentrations of K% coincide with the wall remains, which consist of muddy material. Lower values of K% were found in the surrounding media, which consists of Quaternary sediments. The contrast between the building remains and the surrounding sediments is so clear that it is obvious that GRS is capable of offering solutions to important archaeological problems.

  4. Determination of the natural radioactivity levels in north west of Dukhan, Qatar using high-resolution gamma-ray spectrometry.

    PubMed

    Al-Sulaiti, Huda; Nasir, Tabassum; Al Mugren, K S; Alkhomashi, N; Al-Dahan, N; Al-Dosari, M; Bradley, D A; Bukhari, S; Matthews, M; Regan, P H; Santawamaitre, T; Malain, D; Habib, A

    2012-07-01

    This study is aimed at the determination of the activity concentrations of naturally occuring and technologically enhanced levels of radiation in 34 representative soil samples that have been collected from an inshore oil field area which was found to have, in a previous study, the highest observed value of 226Ra concentration among 129 soil samples. The activity concentrations of 238U and 226Ra have been inferred from gamma-ray transitions associated with their decay progenies and measured using a hyper-pure germanium detector. Details of the sample preparation and the gamma-ray spectroscopic analysis techniques are presented, together with the values of the activity concentrations associated with the naturally occuring radionuclide chains for all the samples collected from NW Dukhan. Discrete-line, gamma-ray energy transitions from spectral lines ranging in energy from ∼100 keV up to 2.6 MeV have been associated with characteristic decays of the various decay products within the 235.8U and 232Th radioactive decay chains. These data have been analyzed, under the assumption of secular equilibrium for the U and Th decay chains. Details of the sample preparation and the gamma-ray spectroscopic analysis techniques are presented. The weighted mean value of the activity concentrations of 226Ra in one of the samples was found to be around a factor of 2 higher than the values obtained in the previous study and approximately a factor of 10 higher than the accepted worldwide average value of 35 Bq/kg. The weighted mean values of the activity concentrations of 232Th and 40K were also deduced and found to be within the worldwide average values of 30 and 400 Bq/kg, respectively. Our previous study reported a value of 201.9±1.5Stat.±13Syst.Bq/kg for 226Ra in one sample and further investigation in the current work determined a measured value for 226Ra of 342.00±1.9Stat.±25Syst.Bq/kg in a sample taken from the same locality. This is significantly higher than all the other

  5. The natural radioactivity measurements in coastal sediment samples along the East Coast of Tamilnadu using gamma spectrometry technique

    SciTech Connect

    Chandramohan, J.; Tholkappian, M.; Harikrishnan, N.; Ravisankar, R.

    2015-08-28

    The natural radioactivity concentration in beach sediment samples collected from Pattipulam to Devanampattinam of East Coast of Tamilnadu have been determined by NaI (TI) gamma ray spectrometer. The specific activity concentrations range from ≤ 2.21 (BDL) to 37.02 Bq kg{sup −1} with a mean of 3.79 Bqkg{sup −1} for {sup 238}U, ≤ 2.11 (BDL) to 643.77 Bqkg{sup −1} with a mean of 49.60 Bqkg{sup −1} for {sup 232}Th and 300.34 Bqkg{sup −1} to 449.08 Bqkg{sup −1} with a mean of 360.23 Bqkg{sup −1} for {sup 40}K. The potential radiological hazards due to natural radionuclides content such as Radium Equivalent activity (Ra{sub eq}), Representative level index (RLI), External hazard index (H{sub ex}), absorbed gamma does rate (D{sub R}), and Annual effective dose rate (AEDR) are estimated to assess the radiation hazard associated with the sediments. The obtained data are compared with the recommended safety limits and international approved values. All the values are well below the recommended safety limits indicating that radiation levels do not poses any significant health hazard to the public in the area as a result of the natural radioactivity of beach sediments. This study may help the baseline data for more extensive works in the same subjects of future studies.

  6. Rapid determination of radon daughters and of artificial radionuclides in air by online gamma-ray spectrometry.

    PubMed

    Hötzl, H; Winkler, R

    1993-01-01

    For the determination of airborne radionuclide concentrations in real time, a fixed filter device was constructed which fits directly onto a germanium detector with standard nuclear electronics and a multichannel analyzer buffer connected via a data line to a personal computer for remote control and on-line spectrum evaluation. The on-line gamma-ray spectrometer was applied to the study of radon decay product concentrations in ground-level air and to the rapid detection of any contamination of the environmental air by artificial radionuclides. At Munich-Neuherberg, depending on the meterological conditions, the measured air concentrations of 214Pb, the first gamma-ray-emitting member of the 222Rn decay series, varied from about 1 to 50 Bq m-3. For the artificial radionuclides 60Co, 131I and 137Cs the detection limits were determined as a function of the varying natural radon daughter concentrations at sampling and counting times of 1 h or 1 day. For these radionuclides minimum detectable air activity concentrations of 0.3 or 0.001 Bq m-3, respectively, were obtained at low radon daughter levels. At high radon daughter levels the respective detection limits were found to be higher by a factor of only about 2.

  7. The determination of the pulse pile-up reject (PUR) counting for X and gamma ray spectrometry

    NASA Astrophysics Data System (ADS)

    Karabıdak, S. M.; Kaya, S.

    2017-02-01

    The collection the charged particles produced by the incident radiation on a detector requires a time interval. If this time interval is not sufficiently short compared with the peaking time of the amplifier, a loss in the recovered signal amplitude occurs. Another major constraint on the throughput of modern x or gamma-ray spectrometers is the time required for the subsequent the pulse processing by the electronics. Two above-mentioned limitations are cause of counting losses resulting from the dead time and the pile-up. The pulse pile-up is a common problem in x and gamma ray radiation detection systems. The pulses pile-up in spectroscopic analysis can cause significant errors. Therefore, inhibition of these pulses is a vital step. A way to reduce errors due to the pulse pile-up is a pile-up inspection circuitry (PUR). Such a circuit rejects some of the pulse pile-up. Therefore, this circuit leads to counting losses. Determination of these counting losses is an important problem. In this work, a new method is suggested for the determination of the pulse pile-up reject.

  8. The use of mercury as a supplementary inner shielding material for low-background gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    Al-Sharkawy, A.; Sharshar, T.; Badran, H. M.

    2013-07-01

    Gamma-ray spectroscopic measurements of low-level environmental samples require the reduction of the background as low as practicable. In the present work, we investigate the advantages of adding Hg passive shielding inside a low-background Pb-shield to further reduce the background radiation. The background count rate achieved by the Pb-shield alone over the energy interval from 25 to 2700 keV, amounts to 8.4 × 10-4 counts/s.keV which is ~ 1.5% of the normal background. The introduction of Hg-shield adds another 15% reduction. On the average, the Hg-shield suppresses the net peak areas of X- and gamma-rays to < 3 and 1% of the normal background, respectively. On the other hand, the reduction in the count rate of these peaks due to the addition of Hg-shield varies according to the energy. The measurements showed no evidence of the presence of cosmogenically produced 194Hg in the measured spectra. An additional 2% reduction was achieved by using neutron moderators.

  9. Determination of total fluorine in five coal reference materials by proton-induced gamma-ray emission spectrometry.

    PubMed

    Roelandts, I; Robaye, G; Delbrouck-Habaru, J M; Weber, G

    1996-03-01

    The direct non-destructive proton-induced gamma-ray emission (PIGE) technique with a germanium detector was applied to the determination of total fluorine concentration in five coal reference materials (BCR 40, NIST 1632b, NIST 1635, SARM 20 and USGS CLB-1). Duplicate analyses were made from five randomly selected bottles of each coal. Individual data are presented and some problems (calibration, proton stopping power, effects of sample heating by the proton beam, background estimation) which were encountered during this study are discussed. Sensitivity and reproducibility of the determinations, and homogeneity of the coal samples with respect to fluorine contents by analysis of variance were investigated. The present data are also compared with the few published values for these reference samples, including other PIGE data. The use of synthetic standards and spiked samples in the present study suggested that the PIGE method was more accurate than other techniques.

  10. Aerial radiation surveys

    SciTech Connect

    Jobst, J.

    1980-01-01

    A recent aerial radiation survey of the surroundings of the Vitro mill in Salt Lake City shows that uranium mill tailings have been removed to many locations outside their original boundary. To date, 52 remote sites have been discovered within a 100 square kilometer aerial survey perimeter surrounding the mill; 9 of these were discovered with the recent aerial survey map. Five additional sites, also discovered by aerial survey, contained uranium ore, milling equipment, or radioactive slag. Because of the success of this survey, plans are being made to extend the aerial survey program to other parts of the Salt Lake valley where diversions of Vitro tailings are also known to exist.

  11. Radiation surveillance using an unmanned aerial vehicle.

    PubMed

    Pöllänen, Roy; Toivonen, Harri; Peräjärvi, Kari; Karhunen, Tero; Ilander, Tarja; Lehtinen, Jukka; Rintala, Kimmo; Katajainen, Tuure; Niemelä, Jarkko; Juusela, Marko

    2009-02-01

    Radiation surveillance equipment was mounted in a small unmanned aerial vehicle. The equipment consists of a commercial CsI detector for count rate measurement and a specially designed sampling unit for airborne radioactive particles. Field and flight tests were performed for the CsI detector in the area where (137)Cs fallout from the Chernobyl accident is 23-45 kBq m(-2). A 3-GBq (137)Cs point source could be detected at the altitude of 50 m using a flight speed of 70 km h(-1) and data acquisition interval of 1s. Respective response for (192)Ir point source is 1 GBq. During the flight, the detector reacts fast to ambient external dose rate rise of 0.1 microSv h(-1), which gives for the activity concentration of (131)I less than 1 kB qm(-3). Operation of the sampler equipped with different type of filters was investigated using wind-tunnel experiments and field tests with the aid of radon progeny. Air flow rate through the sampler is 0.2-0.7 m(3)h(-1) at a flight speed of 70 km h(-1) depending on the filter type in question. The tests showed that the sampler is able to collect airborne radioactive particles. Minimum detectable concentration for transuranium nuclides, such as (239)Pu, is of the order of 0.2 Bq m(-3) or less when alpha spectrometry with no radiochemical sample processing is used for activity determination immediately after the flight. When a gamma-ray spectrometer is used, minimum detectable concentrations for several fission products such as (137)Cs and (131)I are of the order of 1 Bq m(-3).

  12. Determination of the activity concentration levels of the artificial radionuclide137Cs in soil samples collected from Qatar using high-resolution gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    Al-Sulaiti, Huda; Nasir, Tabassum; Al Mugren, K. S.; Alkhomashi, N.; Al-Dahan, N.; Al-Dosari, M.; Bradley, D. A.; Bukhari, S.; Regan, P. H.; Santawamaitre, T.; Malain, D.; Habib, A.; Al-Dosari, Hanan; Daar, Eman

    2016-09-01

    The goal of this study was to establish the first baseline measurements for radioactivity concentration of the artificial radionuclide 137Cs in soil samples collected from the Qatarian peninsula. The work focused on the determination of the activity concentrations levels of man-made radiation in 129 soil samples collected across the landscape of the State of Qatar. All the samples were collected before the most recent accident in Japan, “the 2011 Fukushima Dai-ichi nuclear power plant accident”. The activity 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 radiological map showing the activity concentrations of 137Cs is presented in this work. The concentration wasfound to range from 0.21 to 15.41 Bq/kg. The highest activity concentration of 137Cs was observed in sample no. 26 in North of Qatar. The mean value was found to be around 2.15 ± 0.27 Bq/kg. These values lie within the expected range relative to the countries in the region. It is expected that this contamination is mainly due to the Chernobyl accident on 26 April 1986, but this conclusion cannot be confirmed because of the lack of data before this accident.

  13. LAFARA: a new underground laboratory in the French Pyrénées for ultra low-level gamma-ray spectrometry.

    PubMed

    van Beek, P; Souhaut, M; Lansard, B; Bourquin, M; Reyss, J-L; von Ballmoos, P; Jean, P

    2013-02-01

    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.

  14. Bioactive compounds of fourth generation gamma-irradiated Typhoniumflagelliforme Lodd. mutants based on gas chromatography-mass spectrometry

    NASA Astrophysics Data System (ADS)

    Sianipar, N. F.; Purnamaningsih, R.; Rosaria

    2016-08-01

    Rodent tuber (Typhonium flagelliforme Lodd.) is an Indonesian anticancer medicinal plant. The natural genetic diversity of rodent tuber is low due to vegetative propagation. Plant's genetic diversity has to be increased for obtaining clones which contain a high amount of anticancer compounds. In vitro calli were irradiated with 6 Gy of gamma ray to produce in vitro mutant plantlets. Mutant plantlets were acclimated and propagated in a greenhouse. This research was aimed to identify the chemical compounds in the leaves and tubers ofthe fourth generation of rodent tuber's vegetative mutant clones (MV4) and control plantsby using GC- MS method. Leaves and tubers of MV4 each contained 2 and 5 anticancer compounds which quantities were higher compared to control plants. MV4 leaves contained 5 new anticancer compounds while its tubers contained 3 new anticancer compounds which were not found in control. The new anticancer compounds in leaves were hexadecanoic acid, stigmast-5-en-3-ol, ergost-5-en-3-ol, farnesol isomer a, and oleic acid while the new anticancer compounds in tubers were alpha tocopherol, ergost-5-en-3-ol, and beta-elemene. Rodent tuber mutant clones are very potential to be developed into anticancer drugs.

  15. Systematic influences of gamma-ray spectrometry data near the decision threshold for radioactivity measurements in the environment.

    PubMed

    Zorko, Benjamin; Korun, Matjaž; Mora Canadas, Juan Carlos; Nicoulaud-Gouin, Valerie; Chyly, Pavol; Blixt Buhr, Anna Maria; Lager, Charlotte; Aquilonius, Karin; Krajewski, Pawel

    2016-07-01

    Several methods for reporting outcomes of gamma-ray spectrometric measurements of environmental samples for dose calculations are presented and discussed. The measurement outcomes can be reported as primary measurement results, primary measurement results modified according to the quantification limit, best estimates obtained by the Bayesian posterior (ISO 11929), best estimates obtained by the probability density distribution resembling shifting, and the procedure recommended by the European Commission (EC). The annual dose is calculated from the arithmetic average using any of these five procedures. It was shown that the primary measurement results modified according to the quantification limit could lead to an underestimation of the annual dose. On the other hand the best estimates lead to an overestimation of the annual dose. The annual doses calculated from the measurement outcomes obtained according to the EC's recommended procedure, which does not cope with the uncertainties, fluctuate between an under- and overestimation, depending on the frequency of the measurement results that are larger than the limit of detection. In the extreme case, when no measurement results above the detection limit occur, the average over primary measurement results modified according to the quantification limit underestimates the average over primary measurement results for about 80%. The average over best estimates calculated according the procedure resembling shifting overestimates the average over primary measurement results for 35%, the average obtained by the Bayesian posterior for 85% and the treatment according to the EC recommendation for 89%.

  16. Measurement of natural radioactivity in building materials of Namakkal, Tamil Nadu, India using gamma-ray spectrometry.

    PubMed

    Ravisankar, R; Vanasundari, K; Chandrasekaran, A; Rajalakshmi, A; Suganya, M; Vijayagopal, P; Meenakshisundaram, V

    2012-04-01

    The natural level of radioactivity in building materials is one of the major causes of external exposure to γ-rays. The primordial radionuclides in building materials are one of the sources of radiation hazard in dwellings made of these materials. By the determination of the radioactivity level in building materials, the indoor radiological hazard to human health can be assessed. This is an important precautionary measure whenever the dose rate is found to be above the recommended limits. The aim of this work was to measure the specific activity concentration of (226)Ra, (232)Th and (40)K in commonly used building materials from Namakkal, Tamil Nadu, India, using gamma-ray spectrometer. The radiation hazard due to the total natural radioactivity in the studied building materials was estimated by different approaches. The concentrations of the natural radionuclides and the radium equivalent activity in studied samples were compared with the corresponding results of different countries. From the analysis, it is found that these materials may be safely used as construction materials and do not pose significant radiation hazards.

  17. Reliability of the peak-analysis results in gamma-ray spectrometry for high relative peak-area uncertainties.

    PubMed

    Korun, M; Vodenik, B; Zorko, B

    2015-11-01

    When measurement results with values near the decision threshold are being considered, a relative uncertainty of 60% is expected. Since such measurement results can be reported, the performance of the peak-analysing software for gamma-ray spectra needs to be examined for peaks that have a large relative uncertainty. The investigation was performed on a series of spectra measured with a HPGe detector under identical counting conditions. It was found that under a limit value of the relative peak area uncertainty the peak-analysis results are reliable with respect to both the peak location and the peak area evaluation. At relative uncertainties exceeding this uncertainty, the probability of type-II errors increases and a systematic influence on the peak area occurs, which originates in fluctuations of the continuous background in the vicinity of the peak. For the counting conditions used in this investigation, the limit relative uncertainty is about 35%, and whereas a systematic influence can be taken into account by a correction factor, the frequency of the type-II errors can only be reduced at the expense of increasing the frequency of the type-I errors.

  18. Effect of small potassium-rich dykes on regional gamma-spectrometry image of a potassium-poor volcanic complex: A case from the Doupovské hory Volcanic Complex, NW Czech Republic

    NASA Astrophysics Data System (ADS)

    Zuzana, Skácelová; Vladislav, Rapprich; Bedřich, Mlčoch

    2009-10-01

    Basaltic rocks with low K, U and Th contents dominate the entire Volcanic Complex of the Doupovské hory Mts. Significant potassium anomaly exceeding 1.5 atomic wt.% of potassium over an area of 4 × 8 km and 2 atomic wt.% of potassium over an area of 2 × 6 km was defined by airborne gamma-ray spectrometry above the central part of the Doupovské hory Volcanic Complex. The following detailed field study, supported by field and laboratory gamma-spectrometry measurements and geochemical analyses of rock samples, resulted in discovery of a swarm of potassium-rich trachytic dykes. The existence of such highly-differentiated rocks in the volcanic complex was unknown till present. These dykes are commonly less than 1 m wide, but their potassium content varies between 4 and 8 atomic wt.%. Owing to this high-K composition and relative abundance of dykes, the dyke rocks significantly modify the regional pattern of gamma-spectrometry data. The potassium anomaly cannot be explained by the presence of Flurbühl intrusive body dominated by ijolites and essexites, as all these rocks are poor in K, with potassium typically not exceeding 1.5 wt.%. On the other hand, much more extensive intermediate trachybasaltic lavas with K content varying within the range 1.8-3 wt.% cause only minor or undetectable anomalies.

  19. The use of MCNP and gamma spectrometry in supporting the evaluation of NORM in Libyan oil pipeline scale

    NASA Astrophysics Data System (ADS)

    Habib, Ahmed S.; Bradley, D. A.; Regan, P. H.; Shutt, A. L.

    2010-07-01

    The accumulation of scales in production pipes is a common problem in the oil industry, reducing fluid flow and also leading to costly remedies and disposal issues. Typical materials found in such scale are sulphates and carbonates of calcium and barium, or iron sulphide. Radium arising from the uranium/thorium present in oil-bearing rock formations may replace the barium or calcium in these salts to form radium salts. This creates what is known as technologically enhanced naturally occurring radioactive material (TENORM or simply NORM). NORM is a serious environmental and health and safety issue arising from commercial oil and gas extraction operations. Whilst a good deal has been published on the characterisation and measurement of radioactive scales from offshore oil production, little information has been published regarding NORM associated with land-based facilities such as that of the Libyan oil industry. The ongoing investigation described in this paper concerns an assessment of NORM from a number of land based Libyan oil fields. A total of 27 pipe scale samples were collected from eight oil fields, from different locations in Libya. The dose rates, measured using a handheld survey meter positioned on sample surfaces, ranged from 0.1-27.3 μSv h -1. In the initial evaluations of the sample activity, use is being made of a portable HPGe based spectrometry system. To comply with the prevailing safety regulations of the University of Surrey, the samples are being counted in their original form, creating a need for correction of non-homogeneous sample geometries. To derive a detection efficiency based on the actual sample geometries, a technique has been developed using a Monte Carlo particle transport code (MCNPX). A preliminary activity determination has been performed using an HPGe portable detector system.

  20. Aerial Image Systems

    NASA Astrophysics Data System (ADS)

    Clapp, Robert E.

    1987-09-01

    Aerial images produce the best stereoscopic images of the viewed world. Despite the fact that every optic in existence produces an aerial image, few persons are aware of their existence and possible uses. Constant reference to the eye and other optical systems have produced a psychosis of design that only considers "focal planes" in the design and analysis of optical systems. All objects in the field of view of the optical device are imaged by the device as an aerial image. Use of aerial images in vision and visual display systems can provide a true stereoscopic representation of the viewed world. This paper discusses aerial image systems - their applications and designs and presents designs and design concepts that utilize aerial images to obtain superior visual displays, particularly with application to visual simulation.

  1. FEASIBILITY EVALUATION OF AN AERIAL RADIAC SURVEY SYSTEM

    DTIC Science & Technology

    An aerial radiac monitor system was evaluated in manned and drone aircraft to determine the feasibility of automatically correcting gamma radiation...telemetry system relayed height-corrected information from drone aircraft to a ground station for recording. The equipment demonstrated the...feasibility of per forming aerial radiological survey, with automatic height correction, in manned and drone air craft of the surveillance types now in

  2. 11. Photocopy of aerial photograph (original aerial located in the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Photocopy of aerial photograph (original aerial located in the U.S. Forest Service, Toiyabe National Forest, Carson District Office). AERIAL VIEW OF THE GENOA PEAK ROAD, SPUR. - Genoa Peak Road, Spur, Glenbrook, Douglas County, NV

  3. 18. Photocopy of aerial photograph (original aerial located in the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Photocopy of aerial photograph (original aerial located in the U.S. Forest Service, Toiyabe National Forest, Carson District Office). AERIAL VIEW OF THE GENOA PEAK ROAD SEGMENT - Genoa Peak Road, Glenbrook, Douglas County, NV

  4. Quantification of DNA strand breaks and abasic sites by oxime derivatization and accelerator mass spectrometry: application to gamma-radiation and peroxynitrite.

    PubMed

    Zhou, Xinfeng; Liberman, Rosa G; Skipper, Paul L; Margolin, Yelena; Tannenbaum, Steven R; Dedon, Peter C

    2005-08-01

    We report a highly sensitive method to quantify abasic sites and deoxyribose oxidation products arising in damaged DNA. The method exploits the reaction of aldehyde- and ketone-containing deoxyribose oxidation products and abasic sites with [(14)C]methoxyamine to form stable oxime derivatives, as originally described by Talpaert-Borle and Liuzzi [Reaction of apurinic/apyrimidinic sites with [(14)C]methoxyamine. A method for the quantitative assay of AP sites in DNA, Biochim. Biophys. Acta 740 (1983) 410-416]. The sensitivity of the method was dramatically improved by the application of accelerator mass spectrometry to quantify the (14)C, with a limit of detection of 1 lesion in 10(6) nucleotides in 1 microg of DNA. The method was validated using DNA containing a defined quantity of abasic sites, with a >0.95 correlation between the quantities of abasic sites and those of methoxyamine labels. The original applications of this and similar oxyamine derivatization methods have assumed that abasic sites are the only aldehyde-containing DNA damage products. However, deoxyribose oxidation produces strand breaks and abasic sites containing a variety of degradation products with aldehyde and ketone moieties. To assess the utility of methoxyamine labeling for quantifying strand breaks and abasic sites, the method was applied to plasmid DNA treated with gamma-radiation and peroxynitrite. For gamma-radiation, there was a 0.99 correlation between the quantity of methoxyamine labels and the quantity of strand breaks and abasic sites determined by a plasmid nicking assay; the abasic sites comprised less than 10% of the radiation-induced DNA damage. Studies with peroxynitrite demonstrate that the method, in conjunction with DNA repair enzymes that remove damaged bases to produce aldehydic sugar residues or abasic sites, is also applicable to quantifying nucleobase lesions in addition to strand break products. Compared to other abasic site quantification techniques, the modified

  5. Evaluating airborne and ground based gamma spectrometry methods for detecting particulate radioactivity in the environment: a case study of Irish Sea beaches.

    PubMed

    Cresswell, A J; Sanderson, D C W

    2012-10-15

    In several places, programmes are in place to locate and recover radioactive particles that have the potential to cause detrimental health effects in any member of the public who may encounter them. A model has been developed to evaluate the use of mobile gamma spectrometry systems within such programmes, with particular emphasis on large volume (16l) NaI(Tl) detectors mounted in low flying helicopters. This model uses a validated Monte Carlo code with assessment of local geochemistry and natural and anthropogenic background radiation concentrations and distributions. The results of the model, applied to the example of particles recovered from beaches in the vicinity of Sellafield, clearly show the ability of rapid airborne surveys conducted at 75 m ground clearance and 120 kph speeds to demonstrate the absence of sources greater than 5 MBq (137)Cs within large areas (10-20 km(2)h(-1)), and identify areas requiring further ground based investigation. Lowering ground clearance for airborne surveys to 15m whilst maintaining speeds covering 1-2 km(2) h(-1) can detect buried (137)Cs sources of 0.5MBq or greater activity. A survey design to detect 100 kBq (137)Cs sources at 10 cm depth has also been defined, requiring surveys at <15m ground clearance and <2 ms(-1) ground speed. The response of airborne systems to the Sellafield particles recovered to date has also been simulated, and the proportion of the existing radiocaesium background in the vicinity of the nuclear site has been established. Finally the rates of area coverage and sensitivities of both airborne and ground based approaches are compared, demonstrating the ability of airborne systems to increase the rate of particle recovery in a cost effective manner. The potential for equipment and methodological developments to improve performance are discussed.

  6. Statistical data evaluation in mobile gamma spectrometry: an optimization of on-line search strategies in the scenario of lost point sources.

    PubMed

    Hjerpe, T; Finck, R R; Samuelsson, C

    2001-06-01

    There is a potential risk that hazardous radioactive sources could enter the environment, e.g., via satellite debris, smuggled radioactive goods, or lost metal scrap. From a radiation protection point of view there is a need for rapid and reliable methods for locating and identifying sources. The methods could also be used to locate hot spots after radioactive fallout. Carborne and airborne gamma spectrometry systems are suitable for the task. This work focuses on a situation where the radionuclide to search for is known, which is not an unlikely scenario. The possibility that the source is located near a road can be high, and thus motivating a carborne spectrometer system. The main object is to optimize on-line statistical methods in order to achieve a high probability for locating the point source and still have reasonably few false alarms caused by variations in the natural background radiation. Data were obtained from a carborne 3-L NaI(Tl) detector and two point sources located at various distances from the road. The nuclides used were 137Cs and 131I. Spectra were measured stationary on the road. From these measurements we have reconstructed counts in spectral windows applicable to different speed and sampling times; the time 3 s and speeds 32 and 54 km h(-1) are used in this work. The maximum distance a source can be located from the road and still be detected is estimated with four different statistical analysis methods. This distance is called the critical distance, CD. The method is applied on gross counts in the full energy peak spectral window. For each method alarm levels have been calculated from background data obtained in Scania (Skåne), in the south of Sweden. The results show large differences in CD. With the best approach, the two sources could be detected from about 180 m (137Cs, 6 GBq) and 170 m (131I, 4.5 GBq).

  7. A Users' Guide for the Computer Program ISDMAP: Analysis and Mapping of In-Situ Gamma-Ray Spectrometry and Soil Sample Data

    SciTech Connect

    Reginatto, Marcel; Bailey, Paul; Shebell, Peter

    2000-11-30

    The computer program ISDMAP was written to analyze data from a set of in situ gamma-ray spectrometry measurements on a grid. It can also do a combined analysis of this type of data and data from soil samples. One well-known difficulty with attempting this type of analysis is that such sets of data can never provide enough information to determine a unique solution. This can be understood intuitively since a finite number of measurements cannot be sufficient to determine a continuous distribution (this observation is not restricted to data collected with the in situ technique, but holds for any set of discrete measurements, such as a series of soil samples). One can, however, restrict to particular types of solutions by requiring that they satisfy other conditions in addition to the measurements, and this is the approach taken by ISDMAP. In ISDMAP, the data are analyzed in a different manner depending on whether the data is from a characterization survey or from a post-remediation survey. The ''characterization'' option creates a map of contamination in surface soil that is smooth and fits the data. The ''post-remediation'' option creates a map with a summary of potential hot spots over a constant background level, providing a map of hot spots that might be ''hidden'' in the data. This report describes the operation of ISDMAP in sufficient detail to allow a user to prepare the necessary input files and run the program. The program requires a PC with DOS or a DOS emulator (most Windows machines have this).

  8. Extraction of full absorption peaks in airborne gamma-spectrometry by filtering techniques coupled with a study of the derivatives. Comparison with the window method.

    PubMed

    Guillot, L

    2001-01-01

    In this paper, an adaptation of a spectral profile analysis method, currently used in high-resolution spectrometry, to airborne gamma measurements is presented. A new algorithm has been developed for extraction of full absorption peaks by studying the variations in the spectral profile of data recorded with large-volume NaI detectors (16 l) with a short sampling time (2 s). The use of digital filters, taking into consideration the characteristics of the absorption peaks, significantly reduced the counting fluctuations, making detection possible based on study of the first and second derivatives. The absorption peaks are then obtained by modelling, followed by subtraction of the Compton continuum in the detection window. Compared to the conventional stripping ratio method, spectral profile analysis offers similar performance for the natural radioelements. The 137Cs 1SD detection limit is approximately 1200 Bq/m2 in a natural background of 200 Bq/kg 40K, 33 Bq/kg 238U and 33 Bq/kg 232Th. At low energy the very high continuum leads to detection limits similar to those obtained by the windows method, but the results obtained are more reliable. In the presence of peak overlaps, however, analysis of the spectral profile alone is not sufficient to separate the peaks, and further processing is necessary. Within the framework of environmental monitoring studies, spectral profile analysis is of great interest because it does not require any assumptions about the nature of the nuclides. The calculation of the concentrations from the results obtained is simple and reliable, since only the full absorption contributions are taken into consideration. A quantitative estimate of radioactive anomalies can thus be obtained rapidly.

  9. Aerial photographic reproductions

    USGS Publications Warehouse

    ,

    1975-01-01

    The National Cartographic Information Center of the U.S. Geological Survey maintains records of aerial photographic coverage of the United States and its Territories, based on reports from other Federal agencies as well as State governmental agencies and commercial companies. From these records, the Center furnishes data to prospective purchasers on available photography and the agency holding the aerial film.

  10. EML HASL-300 Method Ga-01-R: Gamma Radioassay

    EPA Pesticide Factsheets

    This method uses gamma spectrometry for measurement of gamma photons emitted from radionuclides. Samples are placed into a standard geometry for gamma counting, typically using an high purity Germanium [HP(Ge)] detector.

  11. Authenticity assessment of gamma- and delta-decalactone from prunus fruits by gas chromatography combustion/pyrolysis isotope ratio mass spectrometry (GC-C/P-IRMS).

    PubMed

    Tamura, Hirotoshi; Appel, Markus; Richling, Elke; Schreier, Peter

    2005-06-29

    Authenticity assessment of gamma-decalactone (1) and delta-decalactone (2) from peach (Prunus persica var. persica), apricot (Prunus armeniaca), and nectarine (Prunus persica var. nectarina) was performed using gas chromatography-isotope ratio mass spectrometry (GC-IRMS) in the combustion (C) and pyrolysis (P) mode. In addition, commercially available synthetic (nature-identical) 1 and 2 as well as biotechnologically produced samples (declared to be "natural") were characterized by their delta(2)H(V)(-)(SMOW) and delta(13)C(V)(-)(PDB) values. For the Prunus fruits under study, rather narrow ranges of delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data of 1, varying from - 34.6 per thousand to - 38.4 per thousand and -160 per thousand to -206 per thousand, respectively, were obtained. Synthetic references of 1 showed delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data ranging from -27.4 per thousand to -28.3 per thousand and -151 per thousand to -184 per thousand, respectively. Samples of 1 declared to be "natural" exhibited ranges from -28.1 per thousand to -29.2 per thousand and -192 per thousand to -286 per thousand for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively. For 2 from peach, apricot, and nectarine, delta(13)C(V)(-)(PDB) values ranging from -34.0 per thousand to -37.9 per thousand were determined; the delta(2)H(V)(-)(SMOW) values ranged from -171 per thousand to -228 per thousand. The delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data for synthetic 2 were -28.2 per thousand and -171 per thousand, respectively, that is, similar to those of 2 from "natural" origin, ranging from -27.7 per thousand to -30.1 per thousand and -185 per thousand to -230 per thousand for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively. GC-C/P-IRMS allowed clear-cut analytical differentiation of the synthetic and "ex-plant" origin of 1 and 2, whereas narrow ranges of delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data were found for samples of

  12. AERIAL METHODS OF EXPLORATION

    DTIC Science & Technology

    The development of photointerpretation techniques for identifying kimberlite pipes on aerial photographs is discussed. The geographic area considered is the Daldyn region, which lies in the zone of Northern Taiga of Yakutiya.

  13. SITE I - AERIAL - MSC

    NASA Image and Video Library

    1965-08-01

    S65-51530 (September 1965) --- Aerial view of Manned Spacecraft Center, Site 1, Houston, Texas, looking north. NOTE: The Manned Spacecraft Center was named Lyndon B. Johnson Space Center in memory of the late President following his death.

  14. SITE I - AERIAL - MSC

    NASA Image and Video Library

    1966-07-01

    S66-42379 (1966) --- Aerial view of construction progress at the Manned Spacecraft Center, Houston, Texas. NOTE: The Manned Spacecraft Center was named Lyndon B. Johnson Space Center in memory of the late President following his death.

  15. Aerial Refueling Test Methods

    DTIC Science & Technology

    2015-04-13

    guide to assess technical compatibility to complement the Aerial Refueling clearance process defined in ARSAG document 43-08-14. The purpose of this...operate the tanker and receiver aircraft. The technical , political, and operational authorities for both aircraft must agree that the appropriate amount of...law, regulation, or technical evaluation. This document serves as an informative database for organizations to consult when developing an aerial

  16. Analysis of gamma-hydroxybutyric acid, DL-lactic acid, glycolic acid, ethylene glycol and other glycols in body fluids by a direct injection gas chromatography-mass spectrometry assay for wide use.

    PubMed

    Van Hee, Paul; Neels, Hugo; De Doncker, Mireille; Vrydags, Nicolas; Schatteman, Katinka; Uyttenbroeck, Wim; Hamers, Nicole; Himpe, Dirk; Lambert, Willy

    2004-01-01

    Analysis of blood of severely intoxicated patients always requires prompt investigation. Diagnosis of intoxication with ethylene glycol, gamma-hydroxybutyric acid or D-lactic acid takes hours, since several different procedures are required. Rapid derivatization of the common hydroxyl function may resolve this analytical problem. Here we describe a fast method for the simultaneous measurement of ethylene glycol, glycolic acid, gamma-hydroxybutyric acid and racemic lactic acid. Only 20 microl of serum, plasma or urine are required for immediate derivatization at 70 degrees C with 750 microl of bis-N,O-trimethylsilyl trifluoroacetamide after adding 20 microl of internal standard solution (1,3-propylene glycol) and 20 microl of the catalyst dimethylformamide. After centrifugation an aliquot is transferred to a gas chromatographic system and analyzed with electron-impact mass spectrometry in selective ion monitoring mode. The derivatized acids and ethylene glycol are well separated and detected with a limit of detection ranging from 0.12 mg/l for ethylene glycol to 0.95 mg/l for gamma-hydroxybutyric acid, while the limit of quantification ranged from 0.4 mg/l for ethylene glycol to 3.15 mg/l for gamma-hydroxybutyric acid. The method is linear from 0.5 to 1800 mg/l blood for ethylene glycol, from 0.7 to 1200 mg/l for lactic acid, from 1.2 to 1800 mg/l for glycolic acid, and from 3.2 to 200 mg/l for gamma-hydroxybutyric acid, with analytical recoveries, accuracy, day-to-day and within-day precision well within the required limits. Total analysis time with one calibrator was 30 min, derivatization time included. This method is very suitable for emergency toxicology, since several toxic substances can be quantified simultaneously in a fast and sensitive manner.

  17. Radiation metabolomics. 3. Biomarker discovery in the urine of gamma-irradiated rats using a simplified metabolomics protocol of gas chromatography-mass spectrometry combined with random forests machine learning algorithm.

    PubMed

    Lanz, Christian; Patterson, Andrew D; Slavík, Josef; Krausz, Kristopher W; Ledermann, Monika; Gonzalez, Frank J; Idle, Jeffrey R

    2009-08-01

    Abstract Radiation metabolomics employing mass spectral technologies represents a plausible means of high-throughput minimally invasive radiation biodosimetry. A simplified metabolomics protocol is described that employs ubiquitous gas chromatography-mass spectrometry and open source software including random forests machine learning algorithm to uncover latent biomarkers of 3 Gy gamma radiation in rats. Urine was collected from six male Wistar rats and six sham-irradiated controls for 7 days, 4 prior to irradiation and 3 after irradiation. Water and food consumption, urine volume, body weight, and sodium, potassium, calcium, chloride, phosphate and urea excretion showed major effects from exposure to gamma radiation. The metabolomics protocol uncovered several urinary metabolites that were significantly up-regulated (glyoxylate, threonate, thymine, uracil, p-cresol) and down-regulated (citrate, 2-oxoglutarate, adipate, pimelate, suberate, azelaate) as a result of radiation exposure. Thymine and uracil were shown to derive largely from thymidine and 2'-deoxyuridine, which are known radiation biomarkers in the mouse. The radiation metabolomic phenotype in rats appeared to derive from oxidative stress and effects on kidney function. Gas chromatography-mass spectrometry is a promising platform on which to develop the field of radiation metabolomics further and to assist in the design of instrumentation for use in detecting biological consequences of environmental radiation release.

  18. Toward prompt gamma spectrometry for monitoring boron distributions during extra corporal treatment of liver metastases by boron neutron capture therapy: a Monte Carlo simulation study.

    PubMed

    Khelifi, R; Nievaart, V A; Bode, P; Moss, R L; Krijger, G C

    2009-07-01

    A Monte Carlo calculation was carried out for boron neutron capture therapy (BNCT) of extra corporal liver phantom. The present paper describes the basis for a subsequent clinical application of the prompt gamma spectroscopy set-up aimed at in vivo monitoring of boron distribution. MCNP code was used first to validate the homogeneity in thermal neutron field in the liver phantom and simulate the gamma ray detection system (collimator and detector) in the treatment room. The gamma ray of 478 keV emitted by boron in small specific region can be detected and a mathematical formalism was used for the tomography image reconstruction.

  19. Aerial Photography Summary Record System

    USGS Publications Warehouse

    ,

    1998-01-01

    The Aerial Photography Summary Record System (APSRS) describes aerial photography projects that meet specified criteria over a given geographic area of the United States and its territories. Aerial photographs are an important tool in cartography and a number of other professions. Land use planners, real estate developers, lawyers, environmental specialists, and many other professionals rely on detailed and timely aerial photographs. Until 1975, there was no systematic approach to locate an aerial photograph, or series of photographs, quickly and easily. In that year, the U.S. Geological Survey (USGS) inaugurated the APSRS, which has become a standard reference for users of aerial photographs.

  20. Aerial Radiation Detection

    SciTech Connect

    W. M. Quam

    1999-09-30

    An airborne system designed for the detection of radioactive sources on the soil surface from an aircraft normally senses gamma rays emitted by the source. Gamma rays have the longest path length (least attenuation) through the air of any of the common radioactive emissions and will thus permit source detection at large distances. A secondary benefit from gamma rays detection if that nearly all radioactive isotopes can be identified by the spectrum of gammas emitted. Major gaseous emissions from fuel processing plants emit gammas that may be detected and identified. Some types of special nuclear material also emit neutrons which are also useful for detection at a distance.

  1. Anatomy and histophysiology of the periosteum: quantification of the periosteal blood supply to the adjacent bone with 85Sr and gamma spectrometry.

    PubMed

    Chanavaz, M

    1995-01-01

    The periosteum or periosteal membrane is a continuous composite fibroelastic covering membrane of the bone to which it is intimately linked. Although the bone cortex is the main beneficiary of the principal anatomical and physiological functions of the periosteal membrane, the behavior of the entire bone remains closely influenced by periosteal activity. These principal functions are related to the cortical blood supply, osteogenesis, and muscle and ligament attachments. Through its elastic and contractile nature, it participates in the maintenance of bone shape, and plays an important role in metabolic ionic exchange and physiologic distribution of electro-chemical potential differences across its membranous structure. It has also been suggested that the periosteum may have its own specific proprioceptive property. This paper presents a study of the anatomy and histophysiology of the periosteum, and discusses in detail its main functions of cortical blood supply and osteogenesis. It also presents the third intermediary report on a current study of the quantification of cortical vascularization of femoral bone via the periosteum, using an isotonic salt solution containing 85 Strontium. The afferent-efferent (arterio-venous) flows of this solution in the thigh vascular system of guinea pigs were measured by gamma spectrometry after a series of selective macro- and micro-injections of radioactive salt into the femoral arterial system was carried out. Each vascular territory was meticulously selected and the injections were made according to size, starting with the larger vessels, with or without ligatures of neighboring vessels, going progressively to smaller and smaller vessels with diameters not exceeding 100 microns. The principal technical difficulty at this stage of experimentation was related to the identifying and acquiring of appropriate microcatheters. The study also includes a series of measurements after blockage of the transmuscular blood flow and the

  2. 26. Photocopy of aerial photograph (original aerial located in the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. Photocopy of aerial photograph (original aerial located in the U.S. Forest Service, Toiyabe National Forest, Carson District Office). AERIAL VIEW OF THE WESTERN END OF THE KINGS CANYON ROAD SEGMENT, 1993. - Kings Canyon Road, Carson City, Carson City, NV

  3. 27. Photocopy of aerial photograph (original aerial located in the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. Photocopy of aerial photograph (original aerial located in the U.S. Forest Service, Toiyabe National Forest, Carson District Office). AERIAL VIEW OF THE WEST-CENTRAL END OF THE KINGS CANYON ROAD SEGMENT, 1993. - Kings Canyon Road, Carson City, Carson City, NV

  4. Aerial Explorers and Robotic Ecosystems

    NASA Technical Reports Server (NTRS)

    Young, Larry A.; Pisanich, Greg

    2004-01-01

    A unique bio-inspired approach to autonomous aerial vehicle, a.k.a. aerial explorer technology is discussed. The work is focused on defining and studying aerial explorer mission concepts, both as an individual robotic system and as a member of a small robotic "ecosystem." Members of this robotic ecosystem include the aerial explorer, air-deployed sensors and robotic symbiotes, and other assets such as rovers, landers, and orbiters.

  5. Spectral anomaly methods for aerial detection using KUT nuisance rejection

    NASA Astrophysics Data System (ADS)

    Detwiler, R. S.; Pfund, D. M.; Myjak, M. J.; Kulisek, J. A.; Seifert, C. E.

    2015-06-01

    This work discusses the application and optimization of a spectral anomaly method for the real-time detection of gamma radiation sources from an aerial helicopter platform. Aerial detection presents several key challenges over ground-based detection. For one, larger and more rapid background fluctuations are typical due to higher speeds, larger field of view, and geographically induced background changes. As well, the possible large altitude or stand-off distance variations cause significant steps in background count rate as well as spectral changes due to increased gamma-ray scatter with detection at higher altitudes. The work here details the adaptation and optimization of the PNNL-developed algorithm Nuisance-Rejecting Spectral Comparison Ratios for Anomaly Detection (NSCRAD), a spectral anomaly method previously developed for ground-based applications, for an aerial platform. The algorithm has been optimized for two multi-detector systems; a NaI(Tl)-detector-based system and a CsI detector array. The optimization here details the adaptation of the spectral windows for a particular set of target sources to aerial detection and the tailoring for the specific detectors. As well, the methodology and results for background rejection methods optimized for the aerial gamma-ray detection using Potassium, Uranium and Thorium (KUT) nuisance rejection are shown. Results indicate that use of a realistic KUT nuisance rejection may eliminate metric rises due to background magnitude and spectral steps encountered in aerial detection due to altitude changes and geographically induced steps such as at land-water interfaces.

  6. Aerial Views of KSC

    NASA Image and Video Library

    2003-07-23

    This aerial view, looking northwest, shows the newly opened Space Commerce Way that winds from S.R 3 on the right to its exit on S.R. 405 (near the top) in the background. The road is the new public access from Merritt Island to the KSC Visitor Complex (seen at top).

  7. Aerial of the VAB

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Even in this aerial view at KSC, the Vehicle Assembly Building is imposing. In front of it is the Launch Control Center. In the background is the Rotation/Processing Facility, next to the Banana Creek. In the foreground is the Saturn Causeway that leads to Launch Pads 39A and 39B.

  8. Aerial photographic reproductions

    USGS Publications Warehouse

    ,

    1971-01-01

    Geological Survey vertical aerial photography is obtained primarily for topographic and geologic mapping. Reproductions from this photography are usually satisfactory for general use. Because reproductions are not stocked, but are custom processed for each order, they cannot be returned for credit or refund.

  9. Development activities of a CdTe/CdZnTe pixel detector for gamma-ray spectrometry with imaging and polarimetry capability in astrophysics

    NASA Astrophysics Data System (ADS)

    Gálvez, J. L.; Hernanz, M.; Álvarez, J. M.; Álvarez, L.; La Torre, M.; Caroli, E.; Lozano, M.; Pellegrini, G.; Ullán, M.; Cabruja, E.; Martínez, R.; Chmeissani, M.; Puigdengoles, C.

    2013-05-01

    In the last few years we have been working on feasibility studies of future instruments in the gamma-ray range, from several keV up to a few MeV, in collaboration with other research institutes. High sensitivities are essential to perform detailed studies of cosmic explosions and cosmic accelerators, e.g., Supernovae, Classical Novae, Supernova Remnants (SNRs), Gamma-Ray Bursts (GRBs), Pulsars, Active Galactic Nuclei (AGN).Cadmium Telluride (CdTe) and Cadmium Zinc Telluride (CdZnTe) are very attractive materials for gamma-ray detection, since they have already demonstrated their great performance onboard current space missions, such as IBIS/INTEGRAL and BAT/SWIFT, and future projects like ASIM onboard the ISS. However, the energy coverage of these instruments is limited up to a few hundred keV, and there has not been yet a dedicated instrument for polarimetry.Our research and development activities aim to study a gamma-ray imaging spectrometer in the MeV range based on CdTe detectors, suited either for the focal plane of a focusing mission or as a calorimeter for a Compton camera. In addition, our undergoing detector design is proposed as the baseline for the payload of a balloon-borne experiment dedicated to hard X- and soft gamma-ray polarimetry, currently under study and called CμSP (CZT μ-Spectrometer Polarimeter). Other research institutes such as INAF-IASF, DTU Space, LIP, INEM/CNR, CEA, are involved in this proposal. We will report on the main features of the prototype we are developing at the Institute of Space Sciences, a gamma-ray detector with imaging and polarimetry capabilities in order to fulfil the combined requirement of high detection efficiency with good spatial and energy resolution driven by the science.

  10. Large-scale radon hazard evaluation in the Oslofjord region of Norway utilizing indoor radon concentrations, airborne gamma ray spectrometry and geological mapping.

    PubMed

    Smethurst, Mark Andrew; Strand, Terje; Sundal, Aud Venke; Rudjord, Anne Liv

    2008-12-15

    We test whether airborne gamma ray spectrometer measurements can be used to estimate levels of radon hazard in the Oslofjord region of Norway. We compile 43,000 line kilometres of gamma ray spectrometer data from 8 airborne surveys covering 10,000 km2 and compare them with 6326 indoor radon measurements. We find a clear spatial correlation between areas with elevated concentrations of uranium daughters in the near surface of the ground and regions with high incidence of elevated radon concentrations in dwellings. This correlation permits cautious use of the airborne data in radon hazard evaluation where direct measurements of indoor radon concentrations are few or absent. In radon hazard evaluation there is a natural synergy between the mapping of radon in indoor air, bedrock and drift geology mapping and airborne gamma ray surveying. We produce radon hazard forecast maps for the Oslofjord region based on a spatial union of hazard indicators from all four of these data sources. Indication of elevated radon hazard in any one of the data sets leads to the classification of a region as having an elevated radon hazard potential. This approach is inclusive in nature and we find that the majority of actual radon hazards lie in the assumed elevated risk regions.

  11. An aerial radiological survey of the Nevada Test Site

    SciTech Connect

    Hendricks, T J; Riedhauser, S R

    1999-12-01

    A team from the Remote Sensing Laboratory conducted an aerial radiological survey of the US Department of Energy's Nevada Test Site including three neighboring areas during August and September 1994. The survey team measured the terrestrial gamma radiation at the Nevada Test Site to determine the levels of natural and man-made radiation. This survey included the areas covered by previous surveys conducted from 1962 through 1993. The results of the aerial survey showed a terrestrial background exposure rate that varied from less than 6 microroentgens per hour (mR/h) to 50 mR/h plus a cosmic-ray contribution that varied from 4.5 mR/h at an elevation of 900 meters (3,000 feet) to 8.5 mR/h at 2,400 meters (8,000 feet). In addition to the principal gamma-emitting, naturally occurring isotopes (potassium-40, thallium-208, bismuth-214, and actinium-228), the man-made radioactive isotopes found in this survey were cobalt-60, cesium-137, europium-152, protactinium-234m an indicator of depleted uranium, and americium-241, which are due to human actions in the survey area. Individual, site-wide plots of gross terrestrial exposure rate, man-made exposure rate, and americium-241 activity (approximating the distribution of all transuranic material) are presented. In addition, expanded plots of individual areas exhibiting these man-made contaminations are given. A comparison is made between the data from this survey and previous aerial radiological surveys of the Nevada Test Site. Some previous ground-based measurements are discussed and related to the aerial data. In regions away from man-made activity, the exposure rates inferred from the gamma-ray measurements collected during this survey agreed very well with the exposure rates inferred from previous aerial surveys.

  12. Low energy photoelectron resonance capture ionization aerosol mass spectrometry of small peptides with cysteine residues: Cys-Gly, [gamma]-Glu-Cys, and glutathione ([gamma]-Glu-Cys-Gly)

    NASA Astrophysics Data System (ADS)

    Geddes, Scott; Zahardis, James; Eisenhauer, Jessica; Petrucci, Giuseppe A.

    2009-04-01

    The photoelectron resonance capture ionization (PERCI) of cysteine (Cys) and small gas-phase neutral peptides that contain the Cys residue (Cys-Gly, [gamma]-Glu-Cys, and glutathione ([gamma]-Glu-Cys-Gly)) is reported. At an ionization energy less than 1 eV two types of dissociative electron attachment ionization were observed for Cys: hydrogen atom loss, resulting in formation of the ion [Cys-H]-, and dissociation of the CH2-SH bond, resulting in formation of the ion [SH]-. The presence of these ions suggests that both the [pi]*(-CO2H) and [sigma]*(C-S) orbitals can act as low energy electrophores on Cys. This ionization trend was observed for the dipeptides Cys-Gly and [gamma]-Glu-Cys as well as glutathione, with evidence that dissociation of the CH2-SH bond in these peptides can also result in ions of the form [M-SH]-. Also measured were ions resulting from bond dissociation of the amide linkage as well as for the amide N-C[alpha] bond. In both of these cases the charge is retained on the fragment containing the nitrogen of the amide bond, indicating that ion formation by the PERCI process is directed by the electron affinity (EA) of the fragments. The backbone fragmentation of the PERCI process appears distinct from other low energy processes, including electron detachment dissociation and electron capture dissociation, as evidenced by the lack of amide C[alpha]-C cleavage; the dependence of ion formation on the EA of the fragments, not their H affinity; and the observation that PERCI is not a directionally restricted mechanism.

  13. Defense Science Board Study on Unmanned Aerial Vehicles and Uninhabited Combat Aerial Vehicles

    DTIC Science & Technology

    2004-02-01

    Defense Science Board Study on Unmanned Aerial Vehicles and Uninhabited Combat Aerial Vehicles February 2004 Office...COVERED - 4. TITLE AND SUBTITLE Defense Science Board Study on Unmanned Aerial Vehicles and Uninhabited Combat Aerial Vehicles 5a. CONTRACT...the Defense Science Board Task Force on Unmanned Aerial Vehicles and Uninhabited Combat Aerial Vehicles I am pleased to forward the final report of

  14. NURE aerial gamma-ray and magnetic reconnaissance survey of portions of New Mexico, Arizona and Texas. Volume II. New Mexico-Carlsbad NI 31-11 Quadrangle. Final report

    SciTech Connect

    Not Available

    1981-09-01

    As part of the Department of Energy (DOE) Nation Uranium Resource Evaluation Program, a rotary-wing high sensitivity radiometric and magnetic survey was flown covering the Carlsbad Quadrangle of the State of New Mexico. The area surveyed consisted of approximately 1732 line miles. The survey was flown with a Sikorsky S58T helicopter equipped with a high sensitivity gamma ray spectrometer which was calibrated at the DOE calibration facilities at Walker Field in Grand Junction, Colorado, and the Dynamic Test Range at Lake Mead, Arizona. Instrumentation and data reduction methods are presented in Volume I of this report. The reduced data is presented in the form of stacked profiles, standard deviation anomaly plots, histogram plots and microfiche listings. The results of the geologic interpretation of the radiometric data together with the profiles, anomaly maps and histograms are presented in this Volume II final report.

  15. 2. AERIAL VIEW OF MINUTEMAN SILOS. Low oblique aerial view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. AERIAL VIEW OF MINUTEMAN SILOS. Low oblique aerial view (original in color) of the two launch silos, covered. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Missile Silo Type, Test Area 1-100, northeast end of Test Area 1-100 Road, Boron, Kern County, CA

  16. Aerial Video Imaging

    NASA Technical Reports Server (NTRS)

    1991-01-01

    When Michael Henry wanted to start an aerial video service, he turned to Johnson Space Center for assistance. Two NASA engineers - one had designed and developed TV systems in Apollo, Skylab, Apollo- Soyuz and Space Shuttle programs - designed a wing-mounted fiberglass camera pod. Camera head and angles are adjustable, and the pod is shaped to reduce vibration. The controls are located so a solo pilot can operate the system. A microprocessor displays latitude, longitude, and bearing, and a GPS receiver provides position data for possible legal references. The service has been successfully utilized by railroads, oil companies, real estate companies, etc.

  17. KSC Aerial Photos SI

    NASA Image and Video Library

    2016-11-28

    KSC Aerial Photos; 00;00;12;00-00;00;28;50 VAB 00;00;28;50 -00;02;11;55 Pad 39B 00;02;11;55 -00;02;31;13 Sand Dunes/Beach 00;02;31;13-00;03;41;33 Pad 39A SpaceX 00;03;41;33-00;04;41;45 LC-41 ULA 00;04;41;45-00;05;54;40 NASA KSC Headquarters 00;05;54;40-00;07;18;00 KSC Industrial Area; Center Contact - Gregory B. Harland (321) 867-2468

  18. Deuterium/hydrogen ratio analysis of thymol, carvacrol, gamma-terpinene and p-cymene in thyme, savory and oregano essential oils by gas chromatography-pyrolysis-isotope ratio mass spectrometry.

    PubMed

    Nhu-Trang, Tran-Thi; Casabianca, Hervé; Grenier-Loustalot, Marie-Florence

    2006-11-03

    Isotope ratio mass spectrometry online coupled with capillary gas chromatography (GC-Py-IRMS) on column INNOWAX is used in the origin specific analysis and the authenticity control of the phenolic essential oils (EOs). Isotopic data delta(2)H(V-SMOW) of thymol and carvacrol in natural essential oils were evidently more depleted than synthetic products (from -49 to 7 per thousand for thymol and -61 per thousand for carvacrol). delta(2)H(V-SMOW) values of p-cymene, gamma-terpinene and thymol in authentic thyme oils (Thymus vulgaris L. and Thymus zygis L.) were found from -300 to -270 per thousand, from -285 to -248 per thousand and from -259 to -234 per thousand, respectively. delta(2)H(V-SMOW) values of carvacrol and p-cymene in authentic oregano oils (Origanum heracleoticum L., Coridothymus capitatus L. and Origanum compactum L.) varied from -223 to -193 per thousand and from -284 to -259 per thousand, respectively. For authentic Satureja montana subsp. montana essential oils, the mean delta(2)H(V-SMOW) value for aromatic compounds were found to be the following: gamma-terpinene -273 per thousand (SD=4.6 per thousand) and p-cymene -283 per thousand (SD=3.0 per thousand), thymol -245 per thousand (SD=1.8 per thousand) and carvacrol -226 per thousand (SD=1.7 per thousand). In addition, p-cymene was previously found as a precursor of the biosynthesis of thymol and carvacrol in thyme oil, thus, we considered p-cymene as an endogenous reference compound (ERC) for D/H ratio analysis. The isotopic fractionation factors alpha(thymol/p-cymene)=1.05 and alpha(carvacrol/p-cymene)=1.08 were obtained and also used to control the authenticity of the phenolic EOs.

  19. Aerial radiological survey of Areas 1, 2, 3, 4, 6, 7, 8, 9, 10, 12, 15 and 17, Yucca Flat, Nevada Test Site, 8 August-2 September 1978

    SciTech Connect

    Fritzsche, A E

    1982-06-01

    An aerial gamma survey was conducted over Yucca Flat during August 1978. A limited quantity of soil samples was obtained and evaluated in support of the aerial survey. Results are presented in the form of exposure rate isopleths from man-made isotopes and estimates of concentrations and inventories of /sup 152/Eu, /sup 137/Cs and /sup 60/Co.

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

    PubMed

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

    2016-02-01

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

  1. Analysis of gamma-hydroxybutyric acid (GHB) in spiked water and beverage samples using solid phase microextraction (SPME) on fiber derivatization/gas chromatography-mass spectrometry (GC/MS).

    PubMed

    Meyers, Jodi E; Almirall, José R

    2005-01-01

    Gamma-Hydroxybutyric acid (GHB) is a CNS depressant that has been abused recreationally for its purported euphoric and relaxation effects and for the purposes of drug facilitated sexual assault due to its sedative and amnesic effects at higher doses. The dramatic increase in the abuse of GHB and association in criminal investigations over the past decade has created the need for forensic laboratories to develop analytical methods to detect GHB in a variety of matrices. The method developed in this work used solid-phase microextraction (SPME) to extract GHB from aqueous samples followed by on-fiber derivatization and analysis by gas chromatography/mass spectrometry (GC/MS). This method detected GHB in aqueous matrices with good sensitivity, high precision, excellent linearity from 0.01 mg/mL to 0.25 mg/mL, and without the need for sample manipulation that could cause interconversion between GHB and its lactone, GBL. The method was successfully applied for detection of GHB in spiked water and beverage samples.

  2. Identification of differentially expressed proteins of gamma-ray irradiated rat intestinal epithelial IEC-6 cells by two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionisation-time of flight mass spectrometry.

    PubMed

    Bo, Zhang; Yongping, Su; Fengchao, Wang; Guoping, Ai; Yongjiang, Wei

    2005-02-01

    To identify proteins involved in the processes of cellular and molecular response to radiation damage repair in intestinal epithelial IEC-6 cells, we comparatively analyzed the proteome of irradiated IEC-6 cells with that of normal cells. A series of methods were used, including two-dimensional gel electrophoresis (Z-DE), PDQuest software analysis of 2-DE gels, peptide mass fingerprinting based on matrix-assisted laser desorption/ionisation-time of flight-mass spectrometry (MALDI-TOF-MS), and Swiss-Prot database searching, to separate and identify differentially expressed proteins. Western blotting and reverse transcriptase polymerase chain reaction (RT-PCR) were used to validate the differentially expressed proteins. Image analysis revealed that averages of 608 +/- 39 and 595 +/- 31 protein spots were detected in normal and irradiated IEC-6 cells, respectively. Sixteen differential protein spots were isolated from gels, and measured with MALDI-TOF-MS. A total of 14 spots yielded good spectra, and 11 spots matched with known proteins after database searching. These proteins were mainly involved in anti-oxidation, metabolism, and protein post-translational processes. Western blotting confirmed that stress-70 protein was down-regulated by gamma-irradiation. Up-regulation of ERP29 was confirmed by RT-PCR, indicating that it is involved in ionizing radiation. The clues provided by the comparative proteome strategy utilized here will shed light on molecular mechanisms of radiation damage repair in intestinal epithelial cells.

  3. Spatial mapping of soil and radioactivity redistribution at the hillslope scale using in-situ gamma spectrometry, terrestrial laser scanning and RFID tags after the Fukushima nuclear accident fallout.

    NASA Astrophysics Data System (ADS)

    Patin, Jeremy; Onda, Yuichi; Noguchi, Takehiro; Parsons, Anthony

    2013-04-01

    In March 2011, the Fukushima Daiichi Nuclear Power Plant disaster, triggered by the Tohoku earthquake and the consequent tsunami, released a large amount of radionuclides in the environment. To provide a rapid assessment of the soil contamination and its potential redistribution, intensive scientific monitoring has been conducted since July 2011 in our study site, located in the Yamakiya district of Kawamata town, in Fukushima prefecture, Japan, about 37 km from the power plant. In this paper, we summarize and analyze a dataset combining multiple innovative methods deployed inside a 5m x 22m bounded hillslope plot. In addition to runoff volumes and sediments radiocesium concentrations, each major rainfall event was followed by in situ gamma spectrometry measurements. In 2012, to trace the complex behavior of sediments inside the plot, about 300 RFID (Radio-Frequency IDentification) tags representing coarse sediments were scattered and their spatial position was periodically checked using a total station. Finally, several high resolutions Digital Elevation Models were acquired with a terrestrial laser scanner to assess the surface structure and changes. The observed processes at the event scale include interrill and rill erosion, as well as local deposition and remobilization phenomenon. Not only do they directly provide information on the erosion spatio-temporal variability and the associated radionuclides transfers, but combined together they can constitute a solid basis to improve and challenge process-based distributed erosion models.

  4. SNIFFER: An aerial platform for the plume phase of a nuclear emergency

    NASA Astrophysics Data System (ADS)

    Castelluccio, D. M.; Cisbani, E.; Frullani, S.

    2012-04-01

    When a nuclear or radiological accident results in a release of a radioactive plume, AGS (Aerial Gamma Spectrometry) systems used in many countries, equipped with passive detectors, can help in giving quantitative assessment on the radiological situation (land surface contamination level) only when the air contamination due to the passage of the travelling plume has become negligible. To overcome this limitation, the Italian Institute of Health has developed and implemented a multi purpose air sampling system based on a fixed wing aircraft, for time-effective, large areas radiological surveillance (to face radiological emergency and to support homeland security). A fixed wing aircraft (Sky Arrow 650) with the front part of the fuselage properly adapted to house the detection equipment has been equipped with a compact air sampling line where the isokinetic sampling is dynamically maintained. Aerosol is collected on a Teflon® filter positioned along the line and hosted on a rotating 4-filters disk. A complex of detectors allows radionuclide identification in the collected aerosol samples. A correlated analysis of these two detectors data allows a quantitative measurement of air as well as ground surface concentration of gamma emitting radioisotopes. Environmental sensors and a GPS receiver support the characterization of the sampling conditions and the temporal and geolocation of the acquired data. Acquisition and control system based on compact electronics and real time software that operate the sampling line actuators, guarantee the dynamical isokinetic condition, and acquire the detectors and sensor data. The system is also equipped with other sampling lines to provide information on the concentration of other chemical pollutants. Operative flights have been carried out in the last years, and performances and results are presented.

  5. Aerial thermography for energy conservation

    NASA Technical Reports Server (NTRS)

    Jack, J. R.

    1978-01-01

    Thermal infrared scanning from an aircraft is a convenient and commercially available means for determining relative rates of energy loss from building roofs. The need to conserve energy as fuel costs makes the mass survey capability of aerial thermography an attractive adjunct to community energy awareness programs. Background information on principles of aerial thermography is presented. Thermal infrared scanning systems, flight and environmental requirements for data acquisition, preparation of thermographs for display, major users and suppliers of thermography, and suggested specifications for obtaining aerial scanning services were reviewed.

  6. Aerial Measuring System Sensor Modeling

    SciTech Connect

    R. S. Detwiler

    2002-04-01

    This project deals with the modeling the Aerial Measuring System (AMS) fixed-wing and rotary-wing sensor systems, which are critical U.S. Department of Energy's National Nuclear Security Administration (NNSA) Consequence Management assets. The fixed-wing system is critical in detecting lost or stolen radiography or medical sources, or mixed fission products as from a commercial power plant release at high flying altitudes. The helicopter is typically used at lower altitudes to determine ground contamination, such as in measuring americium from a plutonium ground dispersal during a cleanup. Since the sensitivity of these instruments as a function of altitude is crucial in estimating detection limits of various ground contaminations and necessary count times, a characterization of their sensitivity as a function of altitude and energy is needed. Experimental data at altitude as well as laboratory benchmarks is important to insure that the strong effects of air attenuation are modeled correctly. The modeling presented here is the first attempt at such a characterization of the equipment for flying altitudes. The sodium iodide (NaI) sensors utilized with these systems were characterized using the Monte Carlo N-Particle code (MCNP) developed at Los Alamos National Laboratory. For the fixed wing system, calculations modeled the spectral response for the 3-element NaI detector pod and High-Purity Germanium (HPGe) detector, in the relevant energy range of 50 keV to 3 MeV. NaI detector responses were simulated for both point and distributed surface sources as a function of gamma energy and flying altitude. For point sources, photopeak efficiencies were calculated for a zero radial distance and an offset equal to the altitude. For distributed sources approximating an infinite plane, gross count efficiencies were calculated and normalized to a uniform surface deposition of 1 {micro}Ci/m{sup 2}. The helicopter calculations modeled the transport of americium-241 ({sup 241}Am

  7. Venus Aerial Platform Modeling Needs

    NASA Astrophysics Data System (ADS)

    Cutts, J. A.; Matthies, L. H.; Thompson, T. W.

    2017-05-01

    The purpose of this paper is to define the models that are important for both engineering and scientific aspects of the design of Venus aerial platform missions and to discuss how they will be applied in assessing technology readiness.

  8. Modeling aerial refueling operations

    NASA Astrophysics Data System (ADS)

    McCoy, Allen B., III

    Aerial Refueling (AR) is the act of offloading fuel from one aircraft (the tanker) to another aircraft (the receiver) in mid flight. Meetings between tanker and receiver aircraft are referred to as AR events and are scheduled to: escort one or more receivers across a large body of water; refuel one or more receivers; or train receiver pilots, tanker pilots, and boom operators. In order to efficiently execute the Aerial Refueling Mission, the Air Mobility Command (AMC) of the United States Air Force (USAF) depends on computer models to help it make tanker basing decisions, plan tanker sorties, schedule aircraft, develop new organizational doctrines, and influence policy. We have worked on three projects that have helped AMC improve its modeling and decision making capabilities. Optimal Flight Planning. Currently Air Mobility simulation and optimization software packages depend on algorithms which iterate over three dimensional fuel flow tables to compute aircraft fuel consumption under changing flight conditions. When a high degree of fidelity is required, these algorithms use a large amount of memory and CPU time. We have modeled the rate of aircraft fuel consumption with respect to AC GrossWeight, Altitude and Airspeed. When implemented, this formula will decrease the amount of memory and CPU time needed to compute sortie fuel costs and cargo capacity values. We have also shown how this formula can be used in optimal control problems to find minimum costs flight plans. Tanker Basing Demand Mismatch Index. Since 1992, AMC has relied on a Tanker Basing/AR Demand Mismatch Index which aggregates tanker capacity and AR demand data into six regions. This index was criticized because there were large gradients along regional boundaries. Meanwhile tankers frequently cross regional boundaries to satisfy the demand for AR support. In response we developed continuous functions to score locations with respect to their proximity to demand for AR support as well as their

  9. Aerial Refueling Clearance Initiation Request

    DTIC Science & Technology

    2016-07-14

    Signed] _________ __________ [Signed] _________ Thomas Swiderek, Omega Air Working Group Lead Group Number 5 Thomas Swiderek, Omega Air Document...Definitions ARSAG Aerial Refueling Systems Advisory Group, International AR Aerial Refueling AAR Air -to- Air Refueling AR Boom Tanker fuel delivery system via...1995 NATO ATP 3.3.4.2, Air to Air Refuelling Ed C Ver 1 Edition D accepting edits through April 2016. Expected Promulgation Sep 2016. Nov 2013 AR

  10. Aerial Refueling Clearance Process Guide

    DTIC Science & Technology

    2014-08-21

    08-2014 2. REPORT TYPE Guidance Document 3. DATES COVERED 2008-2014 4. TITLE AND SUBTITLE Aerial Refueling Clearance Process Guide Attachment: Aerial...ATP-3.3.4.2 covers general operational procedures for AR and national/organizational SRDs cover data and procedures specific to their AR platforms...Receptacle, Probe/Drogue, and BDA Kit. 3.1.3 The items for assessment consideration cover several areas of interface for both the tanker and the

  11. An aerial radiological survey of the area surrounding the Rifle Mill sites, Rifle, Colorado

    SciTech Connect

    Jobst, J

    1980-08-01

    Gamma ray isopleth maps have been constructed from aerial data taken over the old and new Rifle tailing piles near Rifle, Colorado. Spectral data from the more active areas reveal anomalous concentrations of bismuth-214. Tables that convert these anomalous levels to ground concentrations and corresponding exposure rates are included.

  12. Aerial radiometric and magnetic reconnaissance survey of south-central Colorado Trinidad Quadrangle

    SciTech Connect

    Not Available

    1980-01-01

    The results of a high-sensitivity, aerial, gamma-ray spectrometer and magnetometer survey of the Trinidad Quadrangle, Colorado, are presented. Instrumentation and methods are described in Volume 1 of this final report. Statistical and geological analysis of radiometric data revealed 51 uranium anomalies worthy of field-checking as possible prospects.

  13. Status of aerial survey emergency preparedness and ground support equipment, calibration, and sensitivities

    SciTech Connect

    Dahlstrom, T.S.

    1986-01-01

    During the course of EG and G Energy Measurements, Inc. history in aerial surveillance, the scope of response has broadened from routine surveys and accident response with aerial systems, to being prepared to respond to any radiological incident with aerial, ground mobile, and hand-held instrumentation. The aerial survey system presently consists of four MBB BO-105 helicopters outfitted with gamma pods and specialized navigation systems (MRS or URS) that allow the operator and pilot to fly well-defined survey lines. Minimum detectable activities (MDA) for various isotopes range from a few tenths of a mCi to 100 mCI for point sources and from 1 to 200 pCi/g for volume sources.

  14. Gamma Knife

    MedlinePlus

    ... equipment? How is safety ensured? What is this equipment used for? The Gamma Knife® and its associated ... in size. top of page How does the equipment work? The Gamma Knife® utilizes a technique called ...

  15. Chemical constituents from the aerial parts of Gynura bicolor.

    PubMed

    Chen, Jian; Mangelinckx, Sven; Adams, An; Li, Wei-Lin; Wang, Zheng-Tao; De Kimpe, Norbert

    2012-12-01

    Gynura bicolor (Willd.) DC., is used in folk recipes for the treatment of diabetes mellitus in Jiangsu, Zhejiang and Sichuan province in the south of China. A previous pharmacological study proved that the plant showed significant hypoglycemic activity on normal and alloxan-diabetic mice. In this study, two terpenes, four megastigmane-type norisoprenoids and two glycosides were isolated from the aqueous ethanolic extract of the aerial parts of Gynura bicolor and characterized mainly by NMR spectroscopy and mass spectrometry. Thes e compounds were isolated for the first time from this plant, and no evidence could be found for the previous reported presence of megastigmane-type norisoprenoids in the genus Gynura.

  16. Dynamics of aerial target pursuit

    NASA Astrophysics Data System (ADS)

    Pal, S.

    2015-12-01

    During pursuit and predation, aerial species engage in multitasking behavior that involve simultaneous target detection, tracking, decision-making, approach and capture. The mobility of the pursuer and the target in a three dimensional environment during predation makes the capture task highly complex. Many researchers have studied and analyzed prey capture dynamics in different aerial species such as insects and bats. This article focuses on reviewing the capture strategies adopted by these species while relying on different sensory variables (vision and acoustics) for navigation. In conclusion, the neural basis of these capture strategies and some applications of these strategies in bio-inspired navigation and control of engineered systems are discussed.

  17. Aerial detection surveys in the United States

    Treesearch

    E. W. Johnson; D. Wittwer

    2006-01-01

    Aerial detection surveys, also known as aerial sketchmapping, is a remote sensing technique of observing forest change events from an aircraft and documenting them manually onto a map. Data from aerial surveys have become an important component of the Forest Health Monitoring, a national program designed to determine the status, changes, and trends in indicators of...

  18. 47 CFR 32.2421 - Aerial cable.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Aerial cable. 32.2421 Section 32.2421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2421 Aerial cable. (a) This account shall include the original cost of aerial cable and of drop and block wires served by such...

  19. 47 CFR 32.2421 - Aerial cable.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Aerial cable. 32.2421 Section 32.2421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2421 Aerial cable. (a) This account shall include the original cost of aerial cable and of drop and block wires served by such...

  20. 47 CFR 32.2421 - Aerial cable.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Aerial cable. 32.2421 Section 32.2421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2421 Aerial cable. (a) This account shall include the original cost of aerial cable and of drop and block wires served by such...

  1. 47 CFR 32.2421 - Aerial cable.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Aerial cable. 32.2421 Section 32.2421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2421 Aerial cable. (a) This account shall include the original cost of aerial cable and of drop and block wires served by such...

  2. North West Shelf Unmanned Aerial System Trial

    DTIC Science & Technology

    2007-02-01

    North West Shelf Unmanned Aerial System Trial Duncan Craig Intelligence, Surveillance and Reconnaissance Division Defence... Unmanned Aerial System Trial Executive Summary In response to a government policy announcement issued during the lead-up to the 2004...federal election, Defence invited General Atomics Aeronautical Systems Incorporated (GA-ASI) and Northrop Grumman (NG) to participate in an Unmanned Aerial System (UAS

  3. Nematicidal activity of the essential oil of Rhododendron anthopogonoides aerial parts and its constituent compounds against Meloidogyne incognita.

    PubMed

    Bai, Peng Hua; Bai, Chun Qi; Liu, Qi Zhi; Du, Shu Shan; Liu, Zhi Long

    2013-01-01

    Hydrodistilled essential oil from Rhododendron anthopogonoides Maxim. (Ericaceae) aerial parts was analysed by gas chromatography-mass spectrometry (GC-MS). A total of 42 compounds, accounting for 95.48% of the total oil, were identified. The main constituents of the essential oil were benzyl acetone (34.41%), nerolidol (10.19%), 1,4-cineole (8.41%), beta-caryophyllene (5.63%), gamma-elemene (5.10%), and spathulenol (3.06%). Four constituents were isolated from the essential oil based on fractionation. The essential oil of R. anthopogonoides possessed nematicidal activity against the root knot nematode (Meloidogyne incognita) with an LC50 value of 130.11 microg/ml. The main compound of the essential oil, benzyl acetone, exhibited nematicidal activity against M. incognita with an LC50 value of 74.17 microg/ml while 1,4-cineole, nerolidol, and beta-caryophyllene were not nematicidal at a concentration of 5 mg/ml. The essential oil of R. anthopogonoides and benzyl acetone show potential for their development as possible natural nematicides for the control of the root knot nematode.

  4. The chaplins: a family of hydrophobic cell-surface proteins involved in aerial mycelium formation in Streptomyces coelicolor

    PubMed Central

    Elliot, Marie A.; Karoonuthaisiri, Nitsara; Huang, Jianqiang; Bibb, Maureen J.; Cohen, Stanley N.; Kao, Camilla M.; Buttner, Mark J.

    2003-01-01

    The filamentous bacterium Streptomyces coelicolor differentiates by forming specialized, spore-bearing aerial hyphae that grow into the air. Using microarrays, we identified genes that are down-regulated in a mutant unable to erect aerial hyphae. Through this route, we identified a previously unknown layer of aerial mycelium surface proteins (the “chaplins”). The chaplins share a hydrophobic domain of ∼40 residues (the “chaplin domain”), and all have a secretion signal. The five short chaplins (ChpD,E,F,G,H) have one chaplin domain, whereas the three long chaplins (ChpA,B,C) have two chaplin domains and a C-terminal “sorting signal” that targets them for covalent attachment to the cell wall by sortase enzyme. Expression of the two chaplin genes examined (chpE, chpH) depended on aerial hyphae formation but not sporulation, and egfp fusions showed their expression localized to aerial structures. Mass spectrometry of cell wall extracts confirmed that the short chaplins localized to the cell surface. Deletion of chaplin genes caused severe delays in aerial hyphae formation, a phenotype rescued by exogenous application of chaplin proteins. These observations implicate the chaplins in aerial mycelium formation, and suggest that coating of the envelope by the chaplins is required for aerial hyphae to grow out of the aqueous environment of the substrate mycelium into the air. PMID:12832397

  5. Aerial shows Stennis test stands

    NASA Image and Video Library

    2004-04-16

    An aerial photo shows the B-1/B-2 Test Stand (foreground), A-2 Test Stand (middle) and A-1 Test Stand (back). The historic stands have been used to test engines used on every manned Apollo and space shuttle mission.

  6. Constructing aerial photo volume tables.

    Treesearch

    Robert B. Pope

    1962-01-01

    Although most foresters are familiar with the use of aerial photo volume tables, little has been written on how to make them. Certain pitfalls in the construction process have either been ignored or only casually mentioned in the existing literature. The forester tackling his first photo volume table is likely to bypass some of the important considerations without...

  7. Reconnaissance mapping from aerial photographs

    NASA Technical Reports Server (NTRS)

    Weeden, H. A.; Bolling, N. B. (Principal Investigator)

    1975-01-01

    The author has identified the following significant results. Engineering soil and geology maps were successfully made from Pennsylvania aerial photographs taken at scales from 1:4,800 to 1:60,000. The procedure involved a detailed study of a stereoscopic model while evaluating landform, drainage, erosion, color or gray tones, tone and texture patterns, vegetation, and cultural or land use patterns.

  8. Radioactively-hot particles detected in dusts and soils from Northern Japan by combination of gamma spectrometry, autoradiography, and SEM/EDS analysis and implications in radiation risk assessment.

    PubMed

    Kaltofen, Marco; Gundersen, Arnie

    2017-12-31

    After the March 11, 2011, nuclear reactor meltdowns at Fukushima Dai-ichi, 180 samples of Japanese particulate matter (dusts and surface soils) and 235 similar U.S. and Canadian samples were collected and analyzed sequentially by gamma spectrometry, autoradiography, and scanning electron microscopy with energy dispersive X-ray analysis. Samples were collected and analyzed over a five-year period, from 2011 to 2016. Detectable levels of (134)Cs and (137)Cs were found in 142 of 180 (80%) Japanese particulate matter samples. The median radio-cesium specific activity of Japanese particulate samples was 3.2kBqkg(-1)±1.8kBqkg(-1), and the mean was 25.7kBqkg(-1) (σ=72kBqkg(-1)). The U.S. and Canadian mean and median radio‑cesium activity levels were <0.03kBqkg(-1). U.S. and Canadian samples had detectable (134)Cs and (137)Cs in one dust sample out of 32 collected, and four soils out of 74. The maximum US/Canada radio-cesium particulate matter activity was 0.30±0.10kBqkg(-1). The mean in Japan was skewed upward due to nine of the 180 (5%) samples with activities >250kBqkg(-1). This skewness was present in both the 2011 and 2016 sample sets. >300 individual radioactively-hot particles were identified in samples from Japan; composed of 1% or more of the elements cesium, americium, radium, polonium, thorium, tellurium, or strontium. Some particles reached specific activities in the MBqμg(-1) level and higher. No cesium-containing hot particles were found in the U.S. sample set. Only naturally-occurring radionuclides were found in particles from the U.S. background samples. Some of the hot particles detected in this study could cause significant radiation exposures to individuals if inhaled. Exposure models ignoring these isolated hot particles would potentially understate human radiation dose. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Mass spectrometry.

    NASA Technical Reports Server (NTRS)

    Burlingame, A. L.; Johanson, G. A.

    1972-01-01

    Review of the current state of mass spectrometry, indicating its unique importance for advanced scientific research. Mass spectrometry applications in computer techniques, gas chromatography, ion cyclotron resonance, molecular fragmentation and ionization, and isotope labeling are covered. Details are given on mass spectrometry applications in bio-organic chemistry and biomedical research. As the subjects of these applications are indicated alkaloids, carbohydrates, lipids, terpenes, quinones, nucleic acid components, peptides, antibiotics, and human and animal metabolisms. Particular attention is given to the mass spectra of organo-inorganic compounds, inorganic mass spectrometry, surface phenomena such as secondary ion and electron emission, and elemental and isotope analysis. Further topics include mass spectrometry in organic geochemistry, applications in geochronology and cosmochemistry, and organic mass spectrometry.

  10. Mass spectrometry.

    NASA Technical Reports Server (NTRS)

    Burlingame, A. L.; Johanson, G. A.

    1972-01-01

    Review of the current state of mass spectrometry, indicating its unique importance for advanced scientific research. Mass spectrometry applications in computer techniques, gas chromatography, ion cyclotron resonance, molecular fragmentation and ionization, and isotope labeling are covered. Details are given on mass spectrometry applications in bio-organic chemistry and biomedical research. As the subjects of these applications are indicated alkaloids, carbohydrates, lipids, terpenes, quinones, nucleic acid components, peptides, antibiotics, and human and animal metabolisms. Particular attention is given to the mass spectra of organo-inorganic compounds, inorganic mass spectrometry, surface phenomena such as secondary ion and electron emission, and elemental and isotope analysis. Further topics include mass spectrometry in organic geochemistry, applications in geochronology and cosmochemistry, and organic mass spectrometry.

  11. Aerial Photographs and Satellite Images

    USGS Publications Warehouse

    ,

    1997-01-01

    Photographs and other images of the Earth taken from the air and from space show a great deal about the planet's landforms, vegetation, and resources. Aerial and satellite images, known as remotely sensed images, permit accurate mapping of land cover and make landscape features understandable on regional, continental, and even global scales. Transient phenomena, such as seasonal vegetation vigor and contaminant discharges, can be studied by comparing images acquired at different times. The U.S. Geological Survey (USGS), which began using aerial photographs for mapping in the 1930's, archives photographs from its mapping projects and from those of some other Federal agencies. In addition, many images from such space programs as Landsat, begun in 1972, are held by the USGS. Most satellite scenes can be obtained only in digital form for use in computer-based image processing and geographic information systems, but in some cases are also available as photographic products.

  12. Aerial robotic data acquisition system

    SciTech Connect

    Hofstetter, K.J.; Hayes, D.W.; Pendergast, M.M.; Corban, J.E.

    1993-12-31

    A small, unmanned aerial vehicle (UAV), equipped with sensors for physical and chemical measurements of remote environments, is described. A miniature helicopter airframe is used as a platform for sensor testing and development. The sensor output is integrated with the flight control system for real-time, interactive, data acquisition and analysis. Pre-programmed flight missions will be flown with several sensors to demonstrate the cost-effective surveillance capabilities of this new technology.

  13. Aerial Interdiction of WMD Shipments

    DTIC Science & Technology

    2007-01-01

    interdiction near Alaska with russian tu–95 U .S . A ir Fo rc e Download as wallpaper at ndupress.ndu.edu JFQ44[text].indd 34 11/27/06 10:34:17...Download as wallpaper at ndupress.ndu.edu JFQ44[text].indd 37 11/27/06 10:34:24 AM Aerial Interdiction not been widely publicized.21 The doctrine

  14. Telemetry of Aerial Radiological Measurements

    SciTech Connect

    H. W. Clark, Jr.

    2002-10-01

    Telemetry has been added to National Nuclear Security Administration's (NNSA's) Aerial Measuring System (AMS) Incident Response aircraft to accelerate availability of aerial radiological mapping data. Rapid aerial radiological mapping is promptly performed by AMS Incident Response aircraft in the event of a major radiological dispersal. The AMS airplane flies the entire potentially affected area, plus a generous margin, to provide a quick look at the extent and severity of the event. The primary result of the AMS Incident Response over flight is a map of estimated exposure rate on the ground along the flight path. Formerly, it was necessary to wait for the airplane to land before the map could be seen. Now, while the flight is still in progress, data are relayed via satellite directly from the aircraft to an operations center, where they are displayed and disseminated. This permits more timely utilization of results by decision makers and redirection of the mission to optimize its value. The current telemetry capability can cover all of North America. Extension to a global capability is under consideration.

  15. An aerial radiological survey of the Sandia National Laboratories and surrounding area

    SciTech Connect

    Riedhauser, S.R.

    1994-06-01

    A team from the Remote Sensing Laboratory conducted an aerial radiological survey of the area surrounding the Sandia National Laboratories and Kirtland Air Force Base in Albuquerque, New Mexico, during March and April 1993. The survey team measured the terrestrial gamma radiation at the site to determine the levels of natural and man-made radiation. This survey includes the areas covered by a previous survey in 1981. The results of the aerial survey show a background exposure rate which varies between 5 and 18 {mu}R/h plus an approximate 6 {mu}R/h contribution from cosmic rays. The major radioactive isotopes found in this survey were: potassium-40, thallium-208, bismuth-214, and actinium-228, which are all naturally-occurring isotopes, and cobalt-60, cesium-137, and excess amounts of thallium-208 and actinium-228, which are due to human actions in the survey area. In regions away from man-made activity, the exposure rates inferred from this survey`s gamma ray measurements agree almost exactly with the exposure rates inferred from the 1981 survey. In addition to the aerial measurements, another survey team conducted in situ and soil sample radiation measurements at three sites within the survey perimeter. These ground-based measurements agree with the aerial measurements within {+-} 5%.

  16. An aerial radiological survey of the Millstone Nuclear Power Station and surrounding area

    SciTech Connect

    Vojtech, R.J.

    1994-03-01

    An aerial radiological survey was conducted during the period of September 10 to 18, 1990, over a 40-square-mile (104-square-kilometer) area surrounding the Millstone Nuclear Power Station (MNPS). The MNPS is located on the Long Island Sound shoreline, three kilometers south of Waterford, Connecticut. The purpose of the survey was to measure and document the terrestrial gamma ray environment of the plant and surrounding areas. A contour map showing radiation exposure rates at 1 meter above ground level was constructed from the aerial data and overlaid on an aerial photograph and a United States Geological Survey map of the area. The exposure rates within the survey region are quite uniform. The area is characterized by an exposure rate of 10-12 microroentgens per hour including an estimated cosmic ray contribution of 3.6 {mu}R/h. This is typical of natural background. The only exception to the natural background readings is the Millstone station itself, which is characterized by an exposure rate consistent with the standard operation of the reactor units. Radionuclide assays of soil samples and pressurized-ion-chamber gamma ray measurements were obtained at five locations within the survey boundaries. These measurements were taken in support of, and are in agreement with, the aerial data. The radiological environment near the plant is consistent with normal plant operation.

  17. Spatial Feature Evaluation for Aerial Scene Analysis

    SciTech Connect

    Swearingen, Thomas S; Cheriyadat, Anil M

    2013-01-01

    High-resolution aerial images are becoming more readily available, which drives the demand for robust, intelligent and efficient systems to process increasingly large amounts of image data. However, automated image interpretation still remains a challenging problem. Robust techniques to extract and represent features to uniquely characterize various aerial scene categories is key for automated image analysis. In this paper we examined the role of spatial features to uniquely characterize various aerial scene categories. We studied low-level features such as colors, edge orientations, and textures, and examined their local spatial arrangements. We computed correlograms representing the spatial correlation of features at various distances, then measured the distance between correlograms to identify similar scenes. We evaluated the proposed technique on several aerial image databases containing challenging aerial scene categories. We report detailed evaluation of various low-level features by quantitatively measuring accuracy and parameter sensitivity. To demonstrate the feature performance, we present a simple query-based aerial scene retrieval system.

  18. Unmanned Aerial Vehicles Master Plan, 1993.

    DTIC Science & Technology

    2007-11-02

    PHOTOGRAPH THIS SHEET AND RETURN To DTIC-FDAC DTIC 70A DOCUMENT PROCESSMING I~ SlEW -, mmllamm LOAN DOCUMENT DEPARTMENT OF DEFENSE UNMANNED AERIAL VEHICLES (UAV...11 B. Program Executive Officer for Cruise Missiles 3 and Unmanned Aerial Vehicles (PEO[CU...69 I ! I I ivI -- UAV 1993 MASTER PLAN U I EXECUTIVE SUMMARY 3 A. OVERVIEW Unmanned Aerial Vehicles (UAVs)* can make significant

  19. Twenty-First-Century Aerial Mining

    DTIC Science & Technology

    2015-04-01

    Views March–April 2015 Air & Space Power Journal | 129 Twenty-First-Century Aerial Mining Col Michael W. Pietrucha, USAFR On 23 September 2014, a B...52H bomber at high altitude north of Guam accomplished an aviation first—the release of a winged, precision aerial mine (fig. 1). The inert, orange...settled to the bottom to lie in wait for a target. This effort marked the first advance in aerial mine - delivery techniques since 1943 and demonstrated

  20. Raman Spectrometry.

    ERIC Educational Resources Information Center

    Gardiner, Derek J.

    1980-01-01

    Reviews mainly quantitative analytical applications in the field of Raman spectrometry. Includes references to other reviews, new and analytically untested techniques, and novel sampling and instrument designs. Cites 184 references. (CS)

  1. Raman Spectrometry.

    ERIC Educational Resources Information Center

    Gardiner, Derek J.

    1980-01-01

    Reviews mainly quantitative analytical applications in the field of Raman spectrometry. Includes references to other reviews, new and analytically untested techniques, and novel sampling and instrument designs. Cites 184 references. (CS)

  2. An aerial radiological survey of the Paducah Gaseous Diffusion Plant and surrounding area, Paducah, Kentucky

    SciTech Connect

    Not Available

    1992-11-01

    An aerial radiological survey of the Paducah Gaseous Diffusion Plant (PGDP) and surrounding area in Paducah, Kentucky, was conducted during May 15--25, 1990. The purpose of the survey was to measure and document the terrestrial radiological environment at the PGDP and surrounding area for use in effective environmental management and emergency response planning. The aerial survey was flown at an altitude of 61 meters (200 feet) along a series of parallel lines 107 meters (350 feet) apart. The survey encompassed an area of 62 square kilometers (24 square miles), bordered on the north by the Ohio River. The results of the aerial survey are reported as inferred exposure rates at 1 meter above ground level in the form of a gamma radiation contour map. Typical background exposure rates were found to vary from 5 to 12 microroentgens per hour ([mu]R/h). Protactinium-234m, a radioisotope indicative of uranium-238, was detected at several facilities at the PGDR. In support of the aerial survey, ground-based exposure rate and soil sample measurements were obtained at several sites within the survey perimeter. The results of the aerial and ground-based measurements were found to agree within [plus minus]15%.

  3. 28. Photocopy of aerial photograph (original aerial located in U.S. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. Photocopy of aerial photograph (original aerial located in U.S. Forest Service, Toiyabe National Forest, Carson District Office). AERIAL VIEW OF THE CENTRAL SECTION OF THE KINGS CANYON ROAD SEGMENT, 1993. - Kings Canyon Road, Carson City, Carson City, NV

  4. 29. Photocopy of aerial photograph (original aerial located in U.S. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. Photocopy of aerial photograph (original aerial located in U.S. Forest Service, Toiyabe National Forest, Carson District Office). AERIAL VIEW OF THE EASTERN END OF THE KINGS CANYON ROAD SEGMENT, 1993. - Kings Canyon Road, Carson City, Carson City, NV

  5. About cosmic gamma ray lines

    NASA Astrophysics Data System (ADS)

    Diehl, Roland

    2017-06-01

    Gamma ray lines from cosmic sources convey the action of nuclear reactions in cosmic sites and their impacts on astrophysical objects. Gamma rays at characteristic energies result from nuclear transitions following radioactive decays or high-energy collisions with excitation of nuclei. The gamma-ray line from the annihilation of positrons at 511 keV falls into the same energy window, although of different origin. We present here the concepts of cosmic gamma ray spectrometry and the corresponding instruments and missions, followed by a discussion of recent results and the challenges and open issues for the future. Among the lessons learned are the diffuse radioactive afterglow of massive-star nucleosynthesis in 26Al and 60Fe gamma rays, which is now being exploited towards the cycle of matter driven by massive stars and their supernovae; large interstellar cavities and superbubbles have been recognised to be of key importance here. Also, constraints on the complex processes making stars explode as either thermonuclear or core-collapse supernovae are being illuminated by gamma-ray lines, in this case from shortlived radioactivities from 56Ni and 44Ti decays. In particular, the three-dimensionality and asphericities that have recently been recognised as important are enlightened in different ways through such gamma-ray line spectroscopy. Finally, the distribution of positron annihilation gamma ray emission with its puzzling bulge-dominated intensity disctribution is measured through spatially-resolved spectra, which indicate that annihilation conditions may differ in different parts of our Galaxy. But it is now understood that a variety of sources may feed positrons into the interstellar medium, and their characteristics largely get lost during slowing down and propagation of positrons before annihilation; a recent microquasar flare was caught as an opportunity to see positrons annihilate at a source.

  6. A Spherical Aerial Terrestrial Robot

    NASA Astrophysics Data System (ADS)

    Dudley, Christopher J.

    This thesis focuses on the design of a novel, ultra-lightweight spherical aerial terrestrial robot (ATR). The ATR has the ability to fly through the air or roll on the ground, for applications that include search and rescue, mapping, surveillance, environmental sensing, and entertainment. The design centers around a micro-quadcopter encased in a lightweight spherical exoskeleton that can rotate about the quadcopter. The spherical exoskeleton offers agile ground locomotion while maintaining characteristics of a basic aerial robot in flying mode. A model of the system dynamics for both modes of locomotion is presented and utilized in simulations to generate potential trajectories for aerial and terrestrial locomotion. Details of the quadcopter and exoskeleton design and fabrication are discussed, including the robot's turning characteristic over ground and the spring-steel exoskeleton with carbon fiber axle. The capabilities of the ATR are experimentally tested and are in good agreement with model-simulated performance. An energy analysis is presented to validate the overall efficiency of the robot in both modes of locomotion. Experimentally-supported estimates show that the ATR can roll along the ground for over 12 minutes and cover the distance of 1.7 km, or it can fly for 4.82 minutes and travel 469 m, on a single 350 mAh battery. Compared to a traditional flying-only robot, the ATR traveling over the same distance in rolling mode is 2.63-times more efficient, and in flying mode the system is only 39 percent less efficient. Experimental results also demonstrate the ATR's transition from rolling to flying mode.

  7. Unmanned aerial vehicles in astronomy

    NASA Astrophysics Data System (ADS)

    Biondi, Federico; Magrin, Demetrio; Ragazzoni, Roberto; Farinato, Jacopo; Greggio, Davide; Dima, Marco; Gullieuszik, Marco; Bergomi, Maria; Carolo, Elena; Marafatto, Luca; Portaluri, Elisa

    2016-07-01

    In this work we discuss some options for using Unmanned Aerial Vehicles (UAVs) for daylight alignment activities and maintenance of optical telescopes, relating them to a small numbers of parameters, and tracing which could be the schemes, requirements and benefits for employing them both at the stage of erection and maintenance. UAVs can easily reach the auto-collimation points of optical components of the next class of Extremely Large Telescopes. They can be equipped with tools for the measurement of the co-phasing, scattering, and reflectivity of segmented mirrors or environmental parameters like C2n and C2T to characterize the seeing during both the day and the night.

  8. Accuracy of field spectrometry in estimating 137Cs contamination in high altitude alpine soils.

    PubMed

    Agnesod, G; Lazzaron, R; Operti, C; Zappa, C

    2001-01-01

    In situ gamma ray spectrometry is an attractive method for providing information on the concentrations of radionuclides in the soil. This method requires separate knowledge of the soil density and of the radioactivity distribution relative to soil depth. In-field gamma spectrometry measurements were performed together with sampling of the soil at the same site for subsequent gamma spectrometry analysis in the laboratory. Results of 137Cs concentration were compared in order to: (i) verify the effectiveness of in situ gamma spectrometry in averaging local inhomogeneties in the soil; and (ii) quantify the sensitivity of the gamma ray spectrometry soil radioactivity evaluation with respect to the variability of the depth profiles obtained from a single site sampling. The site of study is a high altitude pasture, in the Alpine environment.

  9. Gamma II

    NASA Astrophysics Data System (ADS)

    Barker, Thurburn; Castelaz, M.; Cline, J.; Owen, L.; Boehme, J.; Rottler, L.; Whitworth, C.; Clavier, D.

    2011-05-01

    GAMMA II is the Guide Star Automatic Measuring MAchine relocated from STScI to the Astronomical Photographic Data Archive (APDA) at the Pisgah Astronomical Research Institute (PARI). GAMMA II is a multi-channel laser-scanning microdensitometer that was used to measure POSS and SERC plates to create the Guide Star Catalog and the Digital Sky Survey. The microdensitometer is designed with submicron accuracy in x and y measurements using a HP 5507 laser interferometer, 15 micron sampling, and the capability to measure plates as large as 0.5-m across. GAMMA II is a vital instrument for the success of digitizing the direct, objective prism, and spectra photographic plate collections in APDA for research. We plan several targeted projects. One is a collaboration with Drs. P.D. Hemenway and R. L. Duncombe who plan to scan 1000 plates of 34 minor planets to identify systematic errors in the Fundamental System of celestial coordinates. Another is a collaboration with Dr. R. Hudec (Astronomical Institute, Academy of Sciences of the Czech Republic) who is working within the Gaia Variability Unit CU7 to digitize objective prism spectra on the Henize plates and Burrell-Schmidt plates located in APDA. These low dispersion spectral plates provide optical counterparts of celestial high-energy sources and cataclysmic variables enabling the simulation of Gaia BP/RP outputs. The astronomical community is invited to explore the more than 140,000 plates from 20 observatories now archived in APDA, and use GAMMA II. The process of relocating GAMMA to APDA, re-commissioning, and starting up the production scan programs will be described. Also, we will present planned research and future upgrades to GAMMA II.

  10. Astronomical Methods in Aerial Navigation

    NASA Technical Reports Server (NTRS)

    Beij, K Hilding

    1925-01-01

    The astronomical method of determining position is universally used in marine navigation and may also be of service in aerial navigation. The practical application of the method, however, must be modified and adapted to conform to the requirements of aviation. Much of this work of adaptation has already been accomplished, but being scattered through various technical journals in a number of languages, is not readily available. This report is for the purpose of collecting under one cover such previous work as appears to be of value to the aerial navigator, comparing instruments and methods, indicating the best practice, and suggesting future developments. The various methods of determining position and their application and value are outlined, and a brief resume of the theory of the astronomical method is given. Observation instruments are described in detail. A complete discussion of the reduction of observations follows, including a rapid method of finding position from the altitudes of two stars. Maps and map cases are briefly considered. A bibliography of the subject is appended.

  11. BOREAS Level-0 ER-2 Aerial Photography

    NASA Technical Reports Server (NTRS)

    Newcomer, Jeffrey A.; Dominquez, Roseanne; Hall, Forrest G. (Editor)

    2000-01-01

    For BOReal Ecosystem-Atmosphere Study (BOREAS), the ER-2 and other aerial photography was collected to provide finely detailed and spatially extensive documentation of the condition of the primary study sites. The ER-2 aerial photography consists of color-IR transparencies collected during flights in 1994 and 1996 over the study areas.

  12. A Classroom Simulation of Aerial Photography.

    ERIC Educational Resources Information Center

    Baker, Simon

    1981-01-01

    Explains how a simulation of aerial photography can help students in a college level beginning course on interpretation of aerial photography understand the interrelationships of the airplane, the camera, and the earth's surface. Procedures, objectives, equipment, and scale are discussed. (DB)

  13. 29 CFR 1926.453 - Aerial lifts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... American National Standards for “Vehicle Mounted Elevating and Rotating Work Platforms,” ANSI A92.2-1969, including appendix. Aerial lifts acquired before January 22, 1973 which do not meet the requirements of ANSI... conform with the applicable design and construction requirements of ANSI A92.2-1969. Aerial lifts include...

  14. 29 CFR 1926.453 - Aerial lifts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... American National Standards for “Vehicle Mounted Elevating and Rotating Work Platforms,” ANSI A92.2-1969, including appendix. Aerial lifts acquired before January 22, 1973 which do not meet the requirements of ANSI... conform with the applicable design and construction requirements of ANSI A92.2-1969. Aerial lifts include...

  15. 47 CFR 32.2431 - Aerial wire.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Aerial wire. 32.2431 Section 32.2431... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2431 Aerial wire. (a) This account shall include the original cost of bare line wire and other material used in...

  16. 47 CFR 32.2431 - Aerial wire.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Aerial wire. 32.2431 Section 32.2431... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2431 Aerial wire. (a) This account shall include the original cost of bare line wire and other material used in...

  17. 47 CFR 32.2431 - Aerial wire.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Aerial wire. 32.2431 Section 32.2431... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2431 Aerial wire. (a) This account shall include the original cost of bare line wire and other material used in...

  18. 47 CFR 32.2431 - Aerial wire.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Aerial wire. 32.2431 Section 32.2431... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2431 Aerial wire. (a) This account shall include the original cost of bare line wire and other material used in...

  19. A new G(gamma) chain variant: Hb F-Bron [gamma20(B2)val-->Ala].

    PubMed

    Lacan, Philippe; Burnichon, Nelly; Becchi, Michel; Zanella-Cleon, Isabelle; Aubry, Martine; Couprie, Nicole; Francina, Alain

    2005-01-01

    A new G(gamma) hemoglobin (Hb) variant, Hb F-Bron [gamma20(B2)Val-->Ala] on the first exon of the G(gamma)-globin gene is described. The variant was characterized by DNA sequencing and mass spectrometry (MS). Hematological abnormalities included hypochromia and microcytosis and were probably caused by an interaction with an alpha-thalassemia (thal) (3.7 kb) deletion in the heterozygous state.

  20. Adaptive planning of emergency aerial photogrammetric mission

    NASA Astrophysics Data System (ADS)

    Shen, Fuqiang; Zhu, Qing; Zhang, Junxiao; Miao, Shuangxi; Zhou, Xingxia; Cao, Zhenyu

    2015-12-01

    Aiming at the diversity of emergency aerial photogrammetric mission requirements, complex ground and air environmental constraints make the planning mission time-consuming. This paper presents a fast adaptation for the UAV aerial photogrammetric mission planning. First, Building emergency aerial UAVs mission the unified expression of UAVs model and mechanical model of performance parameters in the semantic space make the integrated expression of mission requirements and low altitude environment. Proposed match assessment method which based on resource and mission efficiency. Made the Adaptive match of UAV aerial resources and mission. According to the emergency aerial resource properties, considering complex air-ground environment and mission requirements constraints. Made accurate design of UAV route. Experimental results show, the method scientific and efficient, greatly enhanced the emergency response rate.

  1. Gamma watermarking

    DOEpatents

    Ishikawa, Muriel Y.; Wood, Lowell L.; Lougheed, Ronald W.; Moody, Kenton J.; Wang, Tzu-Fang

    2004-05-25

    A covert, gamma-ray "signature" is used as a "watermark" for property identification. This new watermarking technology is based on a unique steganographic or "hidden writing" digital signature, implemented in tiny quantities of gamma-ray-emitting radioisotopic material combinations, generally covertly emplaced on or within an object. This digital signature may be readily recovered at distant future times, by placing a sensitive, high energy-resolution gamma-ray detecting instrument reasonably precisely over the location of the watermark, which location may be known only to the object's owner; however, the signature is concealed from all ordinary detection means because its exceedingly low level of activity is obscured by the natural radiation background (including the gamma radiation naturally emanating from the object itself, from cosmic radiation and material surroundings, from human bodies, etc.). The "watermark" is used in object-tagging for establishing object identity, history or ownership. It thus may serve as an aid to law enforcement officials in identifying stolen property and prosecuting theft thereof. Highly effective, potentially very low cost identification-on demand of items of most all types is thus made possible.

  2. Maximizing feature detection in aerial unmanned aerial vehicle datasets

    NASA Astrophysics Data System (ADS)

    Byrne, Jonathan; Laefer, Debra F.; O'Keeffe, Evan

    2017-04-01

    This paper compares several feature detectors applied to imagery from an unmanned aerial vehicle to find the best detection algorithm when applied to datasets that vary in translation and have little or no image overlap. Metrics of inliers and reconstruction accuracy of feature detectors are considered with respect to three-dimensional reconstruction results. The image matching results are tested experimentally, and an approach to detecting false matches is outlined. Results showed that although the detectors varied in the number of keypoints generated, a large number of inliers does not necessarily translate into more points in the final point cloud reconstruction and that the process of comparing a large quantity of redundant keypoints may outweigh the advantage of having the extra points. The results also showed that despite the development of keypoint detectors and descriptors, none of them consistently demonstrated a substantial improvement in the quality of structure from motion reconstruction when applied to a wide range of disparate urban and rural images.

  3. Underwater gamma surveys of Mururoa and Fangataufa lagoons.

    PubMed

    Osvath, I; Povinec, P; Huynh-Ngoc, L; Comanducci, J F

    1999-09-30

    Underwater gamma-ray spectrometry is an effective alternative or complement to traditional sampling and laboratory analyses for applications such as contamination assessment in emergency situations, long-term monitoring of radioactive releases or investigation of sunken radioactive objects. This technique was recently used in a seabed contamination study undertaken at the South Pacific nuclear weapons test sites of the Mururoa and Fangataufa atolls in order to guide and focus sediment core sampling in the areas with highest gamma-emitting radionuclide levels. 60Co inventories estimated on the basis of the underwater gamma-ray spectrometry survey were in good agreement with results previously obtained by traditional sediment sampling and laboratory analysis.

  4. Analysis of expressed sequence tags from a single wheat cultivar facilitates interpretation of tandem mass spectrometry data and discrimination of gamma gliadin proteins that may play different functional roles in flour

    USDA-ARS?s Scientific Manuscript database

    The complement of gamma gliadin genes expressed in the wheat cultivar Butte 86 was evaluated by analyzing publicly available expressed sequence tag (EST) data. Eleven contigs were assembled from 153 Butte 86 ESTs. Nine of the contigs encoded full-length proteins and four of the proteins contained an...

  5. Emission Spectrometry.

    ERIC Educational Resources Information Center

    Keliher, Peter N.; And Others

    1984-01-01

    Presented is a review of selected literature on emission spectrometry published during 1982 and 1983. The review is organized under these headings: books and reviews; spectral descriptions and classifications; instrumentation; standards, samples, nomenclature, calibration, calculations; excitation sources; selected applications; and meetings. (JN)

  6. MEMS Based Micro Aerial Vehicles

    NASA Astrophysics Data System (ADS)

    Joshi, Niranjan; Köhler, Elof; Enoksson, Peter

    2016-10-01

    Designing a flapping wing insect robot requires understanding of insect flight mechanisms, wing kinematics and aerodynamic forces. These subsystems are interconnected and their dependence on one another affects the overall performance. Additionally it requires an artificial muscle like actuator and transmission to power the wings. Several kinds of actuators and mechanisms are candidates for this application with their own strengths and weaknesses. This article provides an overview of the insect scaled flight mechanism along with discussion of various methods to achieve the Micro Aerial Vehicle (MAV) flight. Ongoing projects in Chalmers is aimed at developing a low cost and low manufacturing time MAV. The MAV design considerations and design specifications are mentioned. The wings are manufactured using 3D printed carbon fiber and are under experimental study.

  7. COCOA: tracking in aerial imagery

    NASA Astrophysics Data System (ADS)

    Ali, Saad; Shah, Mubarak

    2006-05-01

    Unmanned Aerial Vehicles (UAVs) are becoming a core intelligence asset for reconnaissance, surveillance and target tracking in urban and battlefield settings. In order to achieve the goal of automated tracking of objects in UAV videos we have developed a system called COCOA. It processes the video stream through number of stages. At first stage platform motion compensation is performed. Moving object detection is performed to detect the regions of interest from which object contours are extracted by performing a level set based segmentation. Finally blob based tracking is performed for each detected object. Global tracks are generated which are used for higher level processing. COCOA is customizable to different sensor resolutions and is capable of tracking targets as small as 100 pixels. It works seamlessly for both visible and thermal imaging modes. The system is implemented in Matlab and works in a batch mode.

  8. How To Obtain Aerial Photographs

    USGS Publications Warehouse

    ,

    1999-01-01

    The U.S. Geological Survey (USGS) maintains an informational data base of aerial photographic coverage of the United States and its territories that dates back to the 1940?s. This information describes photographic projects from the USGS, other Federal, State, and local government agencies, and commercial firms. The pictures on this page show a part of a standard 9- by 9-inch photograph and the results obtained by enlarging the original photograph two and four times. Compare the size of the Qualcomm Stadium, Jack Murphy Field, in San Diego, Calif, and the adjacent parking lot and freeways shown at the different scales. USGS Earth Science Information Center (ESIC) representatives will assist you in locating and ordering photographs. Please submit the completed checklist and a marked map showing your area of interest to any ESIC.

  9. Unmanned Aerial Survey of Elephants

    PubMed Central

    Vermeulen, Cédric; Lejeune, Philippe; Lisein, Jonathan; Sawadogo, Prosper; Bouché, Philippe

    2013-01-01

    The use of a UAS (Unmanned Aircraft System) was tested to survey large mammals in the Nazinga Game Ranch in the south of Burkina Faso. The Gatewing ×100™ equipped with a Ricoh GR III camera was used to test animal reaction as the UAS passed, and visibility on the images. No reaction was recorded as the UAS passed at a height of 100 m. Observations, made on a set of more than 7000 images, revealed that only elephants (Loxodonta africana) were easily visible while medium and small sized mammals were not. The easy observation of elephants allows experts to enumerate them on images acquired at a height of 100 m. We, therefore, implemented an aerial strip sample count along transects used for the annual wildlife foot count. A total of 34 elephants were recorded on 4 transects, each overflown twice. The elephant density was estimated at 2.47 elephants/km2 with a coefficient of variation (CV%) of 36.10%. The main drawback of our UAS was its low autonomy (45 min). Increased endurance of small UAS is required to replace manned aircraft survey of large areas (about 1000 km of transect per day vs 40 km for our UAS). The monitoring strategy should be adapted according to the sampling plan. Also, the UAS is as expensive as a second-hand light aircraft. However the logistic and flight implementation are easier, the running costs are lower and its use is safer. Technological evolution will make civil UAS more efficient, allowing them to compete with light aircraft for aerial wildlife surveys. PMID:23405088

  10. The DOE ARM Aerial Facility

    SciTech Connect

    Schmid, Beat; Tomlinson, Jason M.; Hubbe, John M.; Comstock, Jennifer M.; Mei, Fan; Chand, Duli; Pekour, Mikhail S.; Kluzek, Celine D.; Andrews, Elisabeth; Biraud, S.; McFarquhar, Greg

    2014-05-01

    The Department of Energy Atmospheric Radiation Measurement (ARM) Program is a climate research user facility operating stationary ground sites that provide long-term measurements of climate relevant properties, mobile ground- and ship-based facilities to conduct shorter field campaigns (6-12 months), and the ARM Aerial Facility (AAF). The airborne observations acquired by the AAF enhance the surface-based ARM measurements by providing high-resolution in-situ measurements for process understanding, retrieval-algorithm development, and model evaluation that are not possible using ground- or satellite-based techniques. Several ARM aerial efforts were consolidated into the AAF in 2006. With the exception of a small aircraft used for routine measurements of aerosols and carbon cycle gases, AAF at the time had no dedicated aircraft and only a small number of instruments at its disposal. In this "virtual hangar" mode, AAF successfully carried out several missions contracting with organizations and investigators who provided their research aircraft and instrumentation. In 2009, AAF started managing operations of the Battelle-owned Gulfstream I (G-1) large twin-turboprop research aircraft. Furthermore, the American Recovery and Reinvestment Act of 2009 provided funding for the procurement of over twenty new instruments to be used aboard the G-1 and other AAF virtual-hangar aircraft. AAF now executes missions in the virtual- and real-hangar mode producing freely available datasets for studying aerosol, cloud, and radiative processes in the atmosphere. AAF is also engaged in the maturation and testing of newly developed airborne sensors to help foster the next generation of airborne instruments.

  11. Unmanned aerial survey of elephants.

    PubMed

    Vermeulen, Cédric; Lejeune, Philippe; Lisein, Jonathan; Sawadogo, Prosper; Bouché, Philippe

    2013-01-01

    The use of a UAS (Unmanned Aircraft System) was tested to survey large mammals in the Nazinga Game Ranch in the south of Burkina Faso. The Gatewing ×100™ equipped with a Ricoh GR III camera was used to test animal reaction as the UAS passed, and visibility on the images. No reaction was recorded as the UAS passed at a height of 100 m. Observations, made on a set of more than 7000 images, revealed that only elephants (Loxodonta africana) were easily visible while medium and small sized mammals were not. The easy observation of elephants allows experts to enumerate them on images acquired at a height of 100 m. We, therefore, implemented an aerial strip sample count along transects used for the annual wildlife foot count. A total of 34 elephants were recorded on 4 transects, each overflown twice. The elephant density was estimated at 2.47 elephants/km(2) with a coefficient of variation (CV%) of 36.10%. The main drawback of our UAS was its low autonomy (45 min). Increased endurance of small UAS is required to replace manned aircraft survey of large areas (about 1000 km of transect per day vs 40 km for our UAS). The monitoring strategy should be adapted according to the sampling plan. Also, the UAS is as expensive as a second-hand light aircraft. However the logistic and flight implementation are easier, the running costs are lower and its use is safer. Technological evolution will make civil UAS more efficient, allowing them to compete with light aircraft for aerial wildlife surveys.

  12. Aerial shaking performance of wet Anna's hummingbirds

    PubMed Central

    Ortega-Jimenez, Victor Manuel; Dudley, Robert

    2012-01-01

    External wetting poses problems of immediate heat loss and long-term pathogen growth for vertebrates. Beyond these risks, the locomotor ability of smaller animals, and particularly of fliers, may be impaired by water adhering to the body. Here, we report on the remarkable ability of hummingbirds to perform rapid shakes in order to expel water from their plumage even while in flight. Kinematic performance of aerial versus non-aerial shakes (i.e. those performed while perching) was compared. Oscillation frequencies of the head, body and tail were lower in aerial shakes. Tangential speeds and accelerations of the trunk and tail were roughly similar in aerial and non-aerial shakes, but values for head motions in air were twice as high when compared with shakes while perching. Azimuthal angular amplitudes for both aerial and non-aerial shakes reached values greater than 180° for the head, greater than 45° for the body trunk and slightly greater than 90° for the tail and wings. Using a feather on an oscillating disc to mimic shaking motions, we found that bending increased average speeds by up to 36 per cent and accelerations of the feather tip up to fourfold relative to a hypothetical rigid feather. Feather flexibility may help to enhance shedding of water and reduce body oscillations during shaking. PMID:22072447

  13. Aerial videotape mapping of coastal geomorphic changes

    USGS Publications Warehouse

    Debusschere, Karolien; Penland, Shea; Westphal, Karen A.; Reimer, P. Douglas; McBride, Randolph A.

    1991-01-01

    An aerial geomorphic mapping system was developed to examine the spatial and temporal variability in the coastal geomorphology of Louisiana. Between 1984 and 1990 eleven sequential annual and post-hurricane aerial videotape surveys were flown covering periods of prolonged fair weather, hurricane impacts and subsequent post-storm recoveries. A coastal geomorphic classification system was developed to map the spatial and temporal geomorphic changes between these surveys. The classification system is based on 10 years of shoreline monitoring, analysis of aerial photography for 1940-1989, and numerous field surveys. The classification system divides shorelines into two broad classes: natural and altered. Each class consists of several genetically linked categories of shorelines. Each category is further subdivided into morphologic types on the basis of landform relief, elevation, habitat type, vegetation density and type, and sediment characteristics. The classification is used with imagery from the low-altitude, high-resolution aerial videotape surveys to describe and quantify the longshore and cross-shore geomorphic, sedimentologic, and vegetative character of Louisiana's shoreline systems. The mapping system makes it possible to delineate and map detailed geomorphic habitat changes at a resolution higher than that of conventional vertical aerial photography. Morphologic units are mapped parallel to the regional shoreline from the aerial videotape imagery onto the base maps at a scale of 1:24,000. The base maps were constructed from vertical aerial photography concurrent with the data of the video imagery.

  14. Distribution of radionuclides in the surface sea water developed by aerial radiological survey

    NASA Astrophysics Data System (ADS)

    Inomata, Yayoi; Aoyama, Michio; Hirose, Katsumi; Sanada, Yukihisa; Torii, Tatsuo; Tsubono, Takaki; Tsumune, Daisuke; Yamada, Masatoshi

    2014-05-01

    This study provides new data analysis method of aerial radiological survey to monitor the distribution of anthropogenic radioactivity in surface seawaters as a first attempt. The aerial radiological survey was performed by the U.S. Department of Energy National Nuclear Security Administration (DOE/NNSA) within a 30 km radius of the Fukushima Daiichi Nuclear Power Plant (FNPP1) on 18 April 2011. We found good correlations between the observed concentrations of FNPP1 derived radionuclides (131I, 134Cs, 137Cs) in the surface seawater and gamma-ray dose rates by aerial radiological surveys (correlation coefficients for 131I, 0.89; 134Cs, 0.96;137Cs, 0.95). The detection limits of 131I, 134Cs, and 137Cs in surface seawaters for the aerial radiological survey are 25, 21, 24 Bq L-1, respectively. Based on these relations, we find that the area with high concentrations of the FNPP1 derived radionuclides spread south-southeast from the FNPP1. The maximum concentrations of 131I, 134Cs, and 137Cs reached 303, 456, and 528 Bq L-1, respectively. The131I/134Cs ratios in surface waters of the high activities area are about 0.6-0.7. Considering the radioactive decay of 131I (half-life: 8.021 d), we confirm that radionuclides in the surface seawater of this area are due to direct release from FNPP1 to the ocean. From these results, it is concluded that the aerial radiological survey is very effective to investigate the accurate distribution of anthropogenic radioactivity in the surface seawater. Furthermore, the model reproduced the distribution pattern of the FNPP1 derived radionuclides in surface seawater obtained by the aerial radiological survey, although simulated results by regional ocean model are underestimated.

  15. Gamma Processes

    DTIC Science & Technology

    1986-01-01

    E[exp{-Bn Xn 1 U-Y nU-X vi ] - EeUY )Ee (v+Bu)X1 (2.4) where, in the last step, we have dropped the indices n and n-1 because of stationarity and...1967). "Some Problems of Statistical Inference Relating to Double-Gamma Distribution," Trabajos de Estadistica , 18, 67-87. Hugus, D. K. (1982

  16. Overview of NASA aerial applications research

    NASA Technical Reports Server (NTRS)

    Holmes, B. J.

    1978-01-01

    Aerial applications research conducted by NASA seeks improvements in environmental safety, fuel efficiency, and aircraft productivity and safety. From 1976 to 1978, NASA studied the technology needs of the aerial applications industry and developed in-house research capabilities for meeting those needs. This paper presents the research plans developed by NASA. High potential appears to exist for near term contributions to the industry from existing NASA research capabilities in drift reduction, stall departure safety, and dry materials dispersal system technology. A brief, annotated bibliography is included listing documents recently produced as a result of NASA aerial applications research efforts.

  17. 7 CFR 1755.507 - Aerial cable services.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false Aerial cable services. 1755.507 Section 1755.507... § 1755.507 Aerial cable services. (a) Where more than six pairs are needed initially, and where an aerial service is necessary, the service shall consist of 22 AWG filled aerial cable of a pair size adequate for...

  18. 7 CFR 1755.507 - Aerial cable services.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false Aerial cable services. 1755.507 Section 1755.507... § 1755.507 Aerial cable services. (a) Where more than six pairs are needed initially, and where an aerial service is necessary, the service shall consist of 22 AWG filled aerial cable of a pair size adequate for...

  19. 7 CFR 1755.507 - Aerial cable services.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false Aerial cable services. 1755.507 Section 1755.507... § 1755.507 Aerial cable services. (a) Where more than six pairs are needed initially, and where an aerial service is necessary, the service shall consist of 22 AWG filled aerial cable of a pair size adequate for...

  20. Unmanned Aerial Vehicles: Replacing the Army’s Comanche Helicopter?

    DTIC Science & Technology

    2007-11-02

    This strategic research project explores the possibility of unmanned aerial vehicles replacing the Comanche Helicopter in its doctrinal missions...capabilities of unmanned aerial vehicles , and analyzes unmanned aerial vehicles capabilities against those aviation critical tasks. This research will...Army’s current helicopters, this analysis reveals that unmanned aerial vehicles can only perform 67% of the reconnaissance critical tasks, 50% of the

  1. An aerial radiological survey of the Brookhaven National Laboratory and surrounding area, Upton, New York

    SciTech Connect

    Not Available

    1992-09-01

    An aerial radiological survey was performed from March 21 to March 24, 1990, over approximately a 65-square-kilometer (25-square-mile) area surrounding the Brookhaven National Laboratory (BNL) which is located at the center of Suffolk County, Long Island, New York. All gamma radiation data were collected flying east-west lines spaced 76 meters (250 feet) apart at an altitude of 46 meters (150 feet) above ground level (AGL). Count rates obtained from the aerial platform were converted to exposure rates at 1 meter above the ground. The typical terrestrial-plus-cosmic background exposure rate in the survey area ranged from 5 to 10 microroentgens per hour ([mu]R/h). The reported exposure rate values include an estimated cosmic ray contribution of 3.6 [mu]R/h. Ground-based measurements made two weeks later were compared to the aerial survey results. Pressurized ion chamber readings, soil samples, and in situ high purity germanium measurements were taken from 54 locations within the survey area. Exposure rate values obtained from these measurements were in general agreement with those obtained from the aerial data. A total of 16 areas of man-made radioactivity were identified within the survey boundary. The dominant man-made radioisotopes found were cesium-137, sodium-22, manganese-54, cobalt-58, and cobalt-60. The BNL was previously surveyed in June 1983 and May 1980. The results of the present survey are in good agreement with the results of the previous surveys.

  2. Identifying Southern Forest Types on Aerial Photographs

    Treesearch

    Gene Avery

    1960-01-01

    This booklet has been prepared to assist photo interpreters in recognizing broad forest types on aerial photographs of the South, and to illustrate primary differences between panchromatic and infrared photography from the standpoint of timber type-mapping.

  3. AERIAL - MSC SITE - CONSTRUCTION PROGRESS - MSC

    NASA Image and Video Library

    1963-12-24

    S63-23656 (1963) --- Aerial view of construction progress at the Manned Spacecraft Center, Houston, Texas. NOTE: The Manned Spacecraft Center was named Lyndon B. Johnson Space Center in memory of the late President following his death.

  4. Rangeland monitoring with unmanned aerial vehicles (UAVs)

    USDA-ARS?s Scientific Manuscript database

    Unmanned aerial vehicles (UAVs) have great potential for rangeland management applications, such as monitoring vegetation change, developing grazing strategies, determining rangeland health, and assessing remediation treatment effectiveness. UAVs have several advantages: they can be deployed quickly...

  5. Future Role of Aerial Platforms at Venus

    NASA Astrophysics Data System (ADS)

    Cutts, J. A.; Pauken, M.; Hall, J. L.; Baines, K. H.; Grimm, R.

    2017-02-01

    This paper reviews the brief experience with deploying aerial platforms at Venus, the various mission concepts that have been proposed over the last three decades, and a vision for their application through 2050.

  6. Virtual Gamma Ray Radiation Sources through Neutron Radiative Capture

    SciTech Connect

    Scott Wilde, Raymond Keegan

    2008-07-01

    The countrate response of a gamma spectrometry system from a neutron radiation source behind a plane of moderating material doped with a nuclide of a large radiative neutron capture cross-section exhibits a countrate response analogous to a gamma radiation source at the same position from the detector. Using a planar, surface area of the neutron moderating material exposed to the neutron radiation produces a larger area under the prompt gamma ray peak in the detector than a smaller area of dimensions relative to the active volume of the gamma detection system.

  7. Locating buildings in aerial photos

    NASA Technical Reports Server (NTRS)

    Green, James S.

    1994-01-01

    Algorithms and techniques for use in the identification and location of large buildings in digitized copies of aerial photographs are developed and tested. The building data would be used in the simulation of objects located in the vicinity of an airport that may be detected by aircraft radar. Two distinct approaches are considered. Most building footprints are rectangular in form. The first approach studied is to search for right-angled corners that characterize rectangular objects and then to connect these corners to complete the building. This problem is difficult because many nonbuilding objects, such as street corners, parking lots, and ballparks often have well defined corners which are often difficult to distinguish from rooftops. Furthermore, rooftops come in a number of shapes, sizes, shadings, and textures which also limit the discrimination task. The strategy used linear sequences of different samples to detect straight edge segments at multiple angles and to determine when these segments meet at approximately right-angles with respect to each other. This technique is effective in locating corners. The test image used has a fairly rectangular block pattern oriented about thirty degrees clockwise from a vertical alignment, and the overall measurement data reflect this. However, this technique does not discriminate between buildings and other objects at an operationally suitable rate. In addition, since multiple paths are tested for each image pixel, this is a time consuming task. The process can be speeded up by preprocessing the image to locate the more optimal sampling paths. The second approach is to rely on a human operator to identify and select the building objects and then to have the computer determine the outline and location of the selected structures. When presented with a copy of a digitized aerial photograph, the operator uses a mouse and cursor to select a target building. After a button on the mouse is pressed, with the cursor fully within

  8. Reliable aerial thermography for energy conservation

    NASA Technical Reports Server (NTRS)

    Jack, J. R.; Bowman, R. L.

    1981-01-01

    A method for energy conservation, the aerial thermography survey, is discussed. It locates sources of energy losses and wasteful energy management practices. An operational map is presented for clear sky conditions. The map outlines the key environmental conditions conductive to obtaining reliable aerial thermography. The map is developed from defined visual and heat loss discrimination criteria which are quantized based on flat roof heat transfer calculations.

  9. Aerial righting reflexes in flightless animals.

    PubMed

    Jusufi, Ardian; Zeng, Yu; Full, Robert J; Dudley, Robert

    2011-12-01

    Animals that fall upside down typically engage in an aerial righting response so as to reorient dorsoventrally. This behavior can be preparatory to gliding or other controlled aerial behaviors and is ultimately necessary for a successful landing. Aerial righting reflexes have been described historically in various mammals such as cats, guinea pigs, rabbits, rats, and primates. The mechanisms whereby such righting can be accomplished depend on the size of the animal and on anatomical features associated with motion of the limbs and body. Here we apply a comparative approach to the study of aerial righting to explore the diverse strategies used for reorientation in midair. We discuss data for two species of lizards, the gecko Hemidactylus platyurus and the anole Anolis carolinensis, as well as for the first instar of the stick insect Extatosoma tiaratum, to illustrate size-dependence of this phenomenon and its relevance to subsequent aerial performance in parachuting and gliding animals. Geckos can use rotation of their large tails to reorient their bodies via conservation of angular momentum. Lizards with tails well exceeding snout-vent length, and correspondingly large tail inertia to body inertia ratios, are more effective at creating midair reorientation maneuvers. Moreover, experiments with stick insects, weighing an order of magnitude less than the lizards, suggest that aerodynamic torques acting on the limbs and body may play a dominant role in the righting process for small invertebrates. Both inertial and aerodynamic effects, therefore, can play a role in the control of aerial righting. We propose that aerial righting reflexes are widespread among arboreal vertebrates and arthropods and that they represent an important initial adaptation in the evolution of controlled aerial behavior.

  10. Non-Lethal Unmanned Aerial Vehicles (UAVs)

    DTIC Science & Technology

    1993-06-15

    ELEMENT NO. NO. NO. ACCESSION N.- Same as Item Yb 11. TITLE (Include Security Clasiiicotion) "Non- Lethal Unmanned Aerial Vehicles (UAVs)" (U) 12. PERSONAL...NOTATION Non- Lethal Unmanned Aerial Vehicle (UAV) reflects current terminolcgy. Remotely Piloted Vehicle (RPV) and Drone Aircraft are outdated terms...1?. COSAT CODES tS SUBJECT T-RMS (Cont,’we on reverfe if necesary and identi•y by block number) FIELD GROUP SUB-GROUP UAVs Flight Terminal I

  11. Non-Lethal Unmanned Aerial Vehicles (UVs)

    DTIC Science & Technology

    1993-06-15

    Security Classification) "Non- Lethal Unmanned Aerial Vehicles (UAVs)" (U) ERSONAL AUTHOR(S) 13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT (Year...Month,,Oay) 15. PAGE COUNT Final FROM TO 1 1993 June 15 39 16. SUPPLEMENTARY NOTATION Non- Lethal Unmanned Aerial Vehicle (UAV) reflects current...identify by 3lock number) FIELD GROUP SUB-GROUP UAVs Flight Terminal Payload FLIR Infrared 19. ABSTRACT (Continue on reverse if necessary and

  12. CFD Simulation of Aerial Crop Spraying

    NASA Astrophysics Data System (ADS)

    Omar, Zamri; Qiang, Kua Yong; Mohd, Sofian; Rosly, Nurhayati

    2016-11-01

    Aerial crop spraying, also known as crop dusting, is made for aerial application of pesticides or fertilizer. An agricultural aircraft which is converted from an aircraft has been built to combine with the aerial crop spraying for the purpose. In recent years, many studies on the aerial crop spraying were conducted because aerial application is the most economical, large and rapid treatment for the crops. The main objective of this research is to study the airflow of aerial crop spraying system using Computational Fluid Dynamics. This paper is focus on the effect of aircraft speed and nozzle orientation on the distribution of spray droplet at a certain height. Successful and accurate of CFD simulation will improve the quality of spray during the real situation and reduce the spray drift. The spray characteristics and efficiency are determined from the calculated results of CFD. Turbulence Model (k-ɛ Model) is used for the airflow in the fluid domain to achieve a more accurate simulation. Furthermore, spray simulation is done by setting the Flat-fan Atomizer Model of Discrete Phase Model (DPM) at the nozzle exit. The interaction of spray from each flat-fan atomizer can also be observed from the simulation. The evaluation of this study is validation and grid dependency study using field data from industry.

  13. Endurance bounds of aerial systems

    NASA Astrophysics Data System (ADS)

    Harrington, Aaron M.; Kroninger, Christopher M.

    2014-06-01

    Within the past few years micro aerial vehicles (MAVs) have received much more attention and are starting to proliferate into military as well as civilian roles. However, one of the major drawbacks for this technology currently, has been their poor endurance, usually below 10 minutes. This is a direct result of the inefficiencies inherent in their design. Often times, designers do not consider the various components in the vehicle design and match their performance to the desired mission for the vehicle. These vehicles lack a prescribed set of design guidelines or empirically derived design equations which often limits their design to selection of commercial off-the-shelf components without proper consideration of their affect on vehicle performance. In the current study, the design space for different vehicle configurations has been examined including insect flapping, avian flapping, rotary wing, and fixed wing, and their performance bounds are established. The propulsion system typical of a rotary wing vehicle is analyzed to establish current baselines for efficiency of vehicles at this scale. The power draw from communications is analyzed to determine its impact on vehicle performance. Finally, a representative fixed wing MAV is examined and the effects of adaptive structures as a means for increasing vehicle endurance and range are examined. This paper seeks to establish the performance bounds for micro air vehicles and establish a path forward for future designs so that efficiency may be maximized.

  14. Design and realization of an AEC&AGC system for the CCD aerial camera

    NASA Astrophysics Data System (ADS)

    Liu, Hai ying; Feng, Bing; Wang, Peng; Li, Yan; Wei, Hao yun

    2015-08-01

    An AEC and AGC(Automatic Exposure Control and Automatic Gain Control) system was designed for a CCD aerial camera with fixed aperture and electronic shutter. The normal AEC and AGE algorithm is not suitable to the aerial camera since the camera always takes high-resolution photographs in high-speed moving. The AEC and AGE system adjusts electronic shutter and camera gain automatically according to the target brightness and the moving speed of the aircraft. An automatic Gamma correction is used before the image is output so that the image is better for watching and analyzing by human eyes. The AEC and AGC system could avoid underexposure, overexposure, or image blurring caused by fast moving or environment vibration. A series of tests proved that the system meet the requirements of the camera system with its fast adjusting speed, high adaptability, high reliability in severe complex environment.

  15. An aerial radiological survey of the West Valley Demonstration Project and surrounding area, West Valley, New York

    SciTech Connect

    Berry, H.A.

    1991-09-01

    An aerial radiological survey of the West Valley Demonstration Project and the surrounding area was conducted from mid-August through early September 1984 by EG G Energy Measurements, Inc. for the United States Department of Energy. The radiological survey was part of the United States Department of Energy Comprehensive Integrated Remote Sensing (CIRS) program, which provides state-of-the-art remote sensing to support the needs of the various DOE facilities. The survey consisted of airborne measurements of both natural and man-made gamma radiation emanating from the terrestrial surface. These measurements allowed an estimate of the distribution of isotopic concentrations in the area surrounding the project site. Results are reported as isopleths superimposed on aerial photographs of the area. Gamma ray energy spectra are also presented for the net man-made radionuclides. 8 refs., 16 figs., 9 tabs.

  16. Aerial photo SBVC1962". Photo no. 360. Low oblique aerial view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Aerial photo -SBVC-1962". Photo no. 360. Low oblique aerial view of the campus, looking southeast. Stamped on the rear: "Ron Wilhite, Sun-Telegram photo, file, 10/22/62/ - San Bernardino Valley College, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  17. Integration of aerial imaging and variable-rate technology for site-specific aerial herbicide application

    USDA-ARS?s Scientific Manuscript database

    As remote sensing and variable rate technology are becoming more available for aerial applicators, practical methodologies on effective integration of these technologies are needed for site-specific aerial applications of crop production and protection materials. The objectives of this study were to...

  18. Aerial radiometric and magnetic reconnaissance survey of south-central Colorado Trinidad Quadrangle. Volume 1. Instrumentation and methods

    SciTech Connect

    Not Available

    1980-01-01

    Instrumentation and methods described were used for a Department of Energy (DOE) sponsored high-sensitivity, aerial gamma-ray spectrometer and magnetometer survey of the Trinidad, Colorado, NTMS, 1:250,000-scale quadrangle. The survey was carried out by Texas Instruments Incorporated under Bendix Field Engineering Corporation Subcontract No. 79-263-L. Objective of the work was to define areas showing surface indications of a generally higher uranium content where detailed exploration for uranium would most likely be successful.

  19. Measurement of radionuclide activities induced in target components of an IBA CYCLONE 18/9 by gamma-ray spectrometry with HPGe and LaBr3: Ce detectors.

    PubMed

    Tomarchio, Elio

    2014-08-01

    Cyclotrons are used worldwide to produce radiopharmaceuticals by proton irradiation of a suitable target. The intense secondary neutron beam generated by proton interactions with the target induce high radionuclide activities in the target assembly parts that may result in an exposure to high dose levels of the operators during maintenance. The main goal of this work is to evaluate gamma-emitting radionuclide activities induced in Havar foils and titanium windows of a target assembly and carousel stripper forks of an IBA CYCLONE 18/9 cyclotron. The knowledge of radionuclide inventory for each component is required by many companies to assess risk for operators before waste handling and disposal. Gamma-ray spectrometric analyses were carried out with High Purity Germanium (HPGe) and Lanthanum bromide (LaBr3:Ce) scintillation detectors. HPGe is the most used detector for its high energy resolution although it is more suitable for use in a laboratory. The use of LaBr3:Ce can be considered a viable option, particularly in realizing a portable spectrometric system to perform "on-site" measurements and a fast dose rate evaluation before the disposal of activated parts. Due to a high activity of target assembly components replaced after a typical irradiation cycle (about 5000 μAh integrated beam current), gamma-ray spectrometric measurements were performed at a large distance from the detector, even more than 100 cm, or by using a purposely realized Lead-walled collimator. The identification of some key-radionuclides allows to evaluate through simple formulations the dose rate behavior for each component as function of decay time from the last irradiation. The knowledge of the dose rate behavior is a significant piece of information to health physicists for waste handling with safety at work. For an Havar™ foil, the dose rate will be reduced to about 1/1,000 of the starting value after a decay period of approximately 4 y (about 1,500 d), with a relatively safety at

  20. Cloning and characterization of a gene involved in aerial mycelium formation in Streptomyces griseus.

    PubMed Central

    Kudo, N; Kimura, M; Beppu, T; Horinouchi, S

    1995-01-01

    A-factor (2-isocapryloyl-3R-hydroxymethyl-gamma-butyrolactone) is essentially required for aerial mycelium formation and streptomycin production in Streptomyces griseus. A DNA fragment which induced aerial mycelium formation and sporulation in an A-factor-deficient mutant strain, S. griseus HH1, was cloned from this strain on a high-copy-number plasmid. Subcloning and nucleotide sequencing revealed that one open reading frame with 218 amino acids, named AmfC, served as a multicopy suppressor of the aerial mycelium-defective phenotype of the A-factor-deficient strain. The amfC gene did not restore A-factor or streptomycin production, indicating that amfC is involved in aerial mycelium formation independently of secondary metabolic function. Disruption of the chromosomal amfC gene in the wild-type S. griseus strain caused a severe reduction in the abundance of spores but no effect on the shape or size of the spores. The infrequent sporulation of the amfC disruptant was reversed by introduction of amfC on a plasmid. The amfC-defective phenotype was also restored by the orf1590 gene but not by the amfR-amfA-amfB gene cluster. Nucleotide sequences homologous to the amfC gene were distributed in all of 12 Streptomyces species tested, including Streptomyces coelicolor A3(2). The amfC homolog of S. coelicolor A3(2) was cloned and its nucleotide sequence was determined. The AmfC products of S. griseus and S. coelicolor A3(2) showed a 60% identity in their amino acid sequences. Introduction of the amfC gene of S. coelicolor A3(2) into strain HH1 induced aerial mycelium formation and sporulation, which suggests that both play the same functional role in morphogenesis in the strains. PMID:7592414

  1. Looking for an old aerial photograph

    USGS Publications Warehouse

    ,

    1997-01-01

    Attempts to photograph the surface of the Earth date from the 1800's, when photographers attached cameras to balloons, kites, and even pigeons. Today, aerial photographs and satellite images are commonplace. The rate of acquiring aerial photographs and satellite images has increased rapidly in recent years. Views of the Earth obtained from aircraft or satellites have become valuable tools to Government resource planners and managers, land-use experts, environmentalists, engineers, scientists, and a wide variety of other users. Many people want historical aerial photographs for business or personal reasons. They may want to locate the boundaries of an old farm or a piece of family property. Or they may want a photograph as a record of changes in their neighborhood, or as a gift. The U.S. Geological Survey (USGS) maintains the Earth Science Information Centers (ESIC?s) to sell aerial photographs, remotely sensed images from satellites, a wide array of digital geographic and cartographic data, as well as the Bureau?s wellknown maps. Declassified photographs from early spy satellites were recently added to the ESIC offerings of historical images. Using the Aerial Photography Summary Record System database, ESIC researchers can help customers find imagery in the collections of other Federal agencies and, in some cases, those of private companies that specialize in esoteric products.

  2. Studies in humans using deuterium-labeled alpha- and gamma-tocopherols demonstrate faster plasma gamma-tocopherol disappearance and greater gamma-metabolite production.

    PubMed

    Leonard, Scott W; Paterson, Elaine; Atkinson, Jeffrey K; Ramakrishnan, Rajasekhar; Cross, Carroll E; Traber, Maret G

    2005-04-01

    We hypothesized that human plasma alpha- and gamma-tocopherol concentrations reflect differences in their kinetics, especially influenced by gamma-tocopherol metabolism. Vitamin E kinetics were evaluated in humans (n=14) using approximately 50 mg each of an equimolar ratio of d6-alpha- and d2-gamma-tocopheryl acetates administered orally. Mass spectrometry was used to measure deuterated plasma tocopherols, as well as plasma and urinary vitamin E metabolites, alpha- and gamma-carboxyethylhydroxychromans (CEHCs). Plasma d2-gamma-tocopherol fractional disappearance rates (FDR; 1.39+/-0.44 pools/day, mean+/-SD) were more than three times greater than those of d6-alpha-tocopherol (0.33+/-0.11, p<0.001). The d2-gamma-tocopherol half-life was 13+/-4 h compared with 57+/-19 for d6-alpha-tocopherol. Whereas neither plasma nor urinary d6-alpha-CEHC was detectable (limit of detection 1 nmol/L), gamma-CEHC (labeled plus unlabeled) increased from 129+/-20 to 258+/-40 nmol/L by 12 h and returned to baseline by 48 h; at 12 h d2-gamma-CEHC represented 54+/-4% of plasma gamma-CEHC. Women compared with men had a greater d2-gamma-tocopherol FDR (p<0.004) and a greater maximal plasma d2-gamma-CEHC concentration (p<0.02) and CEHC FDR (p<0.007), as well as excreting four times as much d2-gamma-CEHC (p<0.04) in urine. Thus, gamma-tocopherol is rapidly metabolized to gamma-CEHC, and to a greater degree in women than in men, whereas alpha-tocopherol is maintained in the plasma and little is metabolized to alpha-CEHC.

  3. Measurement of gamma and 2 beta + gamma

    SciTech Connect

    Albert, J.

    2005-01-03

    We report on the initial measurements of the angle {gamma} and the sum of angles 2{beta} +{gamma} of the Unitarity Triangle. When compared with indirect information on the value of {gamma} from other measurements of CKM parameters, the measurement of these angles will provide a precise test of Standard Model predictions, as statistics increase. There are several methods for directly measuring {gamma} and 2{beta} +{gamma}. We report on the status of each of these techniques, and the resulting constraints on the values of these angles.

  4. USGS Releases New Digital Aerial Products

    USGS Publications Warehouse

    ,

    2005-01-01

    The U.S. Geological Survey (USGS) Center for Earth Resources Observation and Science (EROS) has initiated distribution of digital aerial photographic products produced by scanning or digitizing film from its historical aerial photography film archive. This archive, located in Sioux Falls, South Dakota, contains thousands of rolls of film that contain more than 8 million frames of historic aerial photographs. The largest portion of this archive consists of original film acquired by Federal agencies from the 1930s through the 1970s to produce 1:24,000-scale USGS topographic quadrangle maps. Most of this photography is reasonably large scale (USGS photography ranges from 1:8,000 to 1:80,000) to support the production of the maps. Two digital products are currently available for ordering: high-resolution scanned products and medium-resolution digitized products.

  5. Detection of linear features in aerial images

    NASA Astrophysics Data System (ADS)

    Gao, Rui

    Over the past decades, considerable progress had been made to develop automatic image interpretation tools in remote sensing. However, there is still a gap between the results and the requirements for accuracy and robustness. Noisy aerial image interpretation, especially for low resolution images, is still difficult. In this thesis, we propose a fully automatic system for linear feature detection in aerial images. We present how the system works on the application of extraction and reconstruction of road and pipeline networks. The work in this thesis is divided by three parts: line detection, feature interpretation, and feature tracking. An improved Hough transform based on orientation information is introduced for the line detection. We explore the Markov random field model and Bayesian filtering for feature interpretation and tracking. Experimental results show that our proposed system is robust and effective to deal with low resolution aerial images.

  6. Resource understanding: a challenge to aerial methods

    USGS Publications Warehouse

    Udall, Stewart L.

    1965-01-01

    Aerial survey methods are speeding acquisition of survey data needed to provide and manage the nation's resources. These methods have been applied to topographic mapping for a number of years and the record clearly shows their advantages in terms of cost and speed in contrast to the ground methods that have been historically employed. Limited use is now being made of aerial methods to assist cadastral surveys, in location, acquisition and development of National Parks, in mapping the geology of the nation, in locating and developing water resources, and in surveys of the oceans. It is the purpose of this paper to call attention to these uses and to encourage the scientific community to further refine aerial methods so that their use may be increased and the veracity of data improved.

  7. Shutter/aperture settings for aerial photography

    NASA Technical Reports Server (NTRS)

    Lockwood, H. E.; Perry, L.

    1976-01-01

    Determination of aerial camera shutter and aperture settings to produce consistently high-quality aerial photographs is a task complicated by numerous variables. Presented in this article are brief discussions of each variable and specific data which may be used for the systematic control of each. The variables discussed include sunlight, aircraft altitude, subject and season, film speed, and optical system. Data which may be used as a base reference are included, and encompass two sets of sensitometric specifications for two film-chemistry processes along with camera-aircraft parameters, which have been established and used to produce good exposures. Information contained here may be used to design and implement an exposure-determination system for aerial photography.

  8. The Development and Flight Testing of an Aerially Deployed Unmanned Aerial System

    NASA Astrophysics Data System (ADS)

    Smith, Andrew

    An investigation into the feasibility of aerial deployed unmanned aerial vehicles was completed. The investigation included the development and flight testing of multiple unmanned aerial systems to investigate the different components of potential aerial deployment missions. The project consisted of two main objectives; the first objective dealt with the development of an airframe capable of surviving aerial deployment from a rocket and then self assembling from its stowed configuration into its flight configuration. The second objective focused on the development of an autopilot capable of performing basic guidance, navigation, and control following aerial deployment. To accomplish these two objectives multiple airframes were developed to verify their completion experimentally. The first portion of the project, investigating the feasibility of surviving an aerial deployment, was completed using a fixed wing glider that following a successful deployment had 52 seconds of controlled flight. Before developing the autopilot in the second phase of the project, the glider was significantly upgraded to fix faults discovered in the glider flight testing and to enhance the system capabilities. Unfortunately to conform to outdoor flight restrictions imposed by the university and the Federal Aviation Administration it was required to switch airframes before flight testing of the new fixed wing platform could begin. As a result, an autopilot was developed for a quadrotor and verified experimentally completely indoors to remain within the limits of governing policies.

  9. Chemical composition of the essential oil of the flowering aerial Parts of Pimpinella monoica.

    PubMed

    Joshi, Rajesh K

    2013-11-01

    The essential oil composition of the flowering aerial parts of Pimpinella monoica Dalzell was analyzed by gas chromatography equipped with flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC/MS). Fifty four compounds were identified, representing 94.7% of the total oil. The main constituents were bornyl acetate (26.2%), beta-caryophyllene (24.0%), limonene (6.7%) and amorpha-4, 11-dien (4.9%). The oil was dominated by sesquiterpene hydrocarbons (40.7%), followed by oxygenated monoterpenes (27.2%), monoterpene hydrocarbons (15.6%), oxygenated sesquiterpenes (7.6%) and others (3.6%).

  10. Metrically preserving the USGS aerial film archive

    USGS Publications Warehouse

    Moe, Donald; Longhenry, Ryan

    2013-01-01

    Since 1972, the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center in Sioux Falls, South Dakota, has provided fi lm-based products to the public. EROS is home to an archive of 12 million frames of analog photography ranging from 1937 to the present. The archive contains collections from both aerial and satellite platforms including programs such as the National High Altitude Program (NHAP), National Aerial Photography Program (NAPP), U.S. Antarctic Resource Center (USARC), Declass 1(CORONA, ARGON, and LANYARD), Declass 2 (KH-7 and KH-9), and Landsat (1972 – 1992, Landsat 1–5).

  11. ARM Unmanned Aerial Systems Implementation Plan

    SciTech Connect

    Schmid, Beat; Ivey, Mark

    2016-11-01

    Recent advances in Unmanned Aerial Systems (UAS) coupled with changes in the regulatory environment for operations of UAS in the National Airspace increase the potential value of UAS to the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility. UAS include unmanned aerial vehicles (UAV) and tethered balloon systems (TBS). The roles UAVs and TBSs could play within the ARM Facility, particularly science questions they could help address, have been discussed in several workshops, reports, and vision documents, including: This document describes the implementation of a robust and vigorous program for use of UAV and TBS for the science missions ARM supports.

  12. Aerial Robotic System for Transportation and Logistics

    NASA Astrophysics Data System (ADS)

    Iwata, Kakuya; Hashimoto, Naohisa; Komoriya, Kiyoshi

    The status quo of a research on a novel aerial robotic system for transportation and logistics is presented. Under a new concept for an aerial robotic transportation system, three-Dimensional Transportation Robots (3DTR) were constructed with twin turbojet engines equipped by high performance noise reduction system and a flexibly jointed delta wing controlled by 2-axis actuators. This vehicle is also stable in the air due to its pendulum structure. The first flight was successfully conducted on November 22, 2005. Flight examination of 3DTR indicates its short take-off and landing (STOL) capability.

  13. MicroProbe Small Unmanned Aerial System

    NASA Technical Reports Server (NTRS)

    Bland, Geoffrey; Miles, Ted

    2012-01-01

    The MicroProbe unmanned aerial system (UAS) concept incorporates twin electric motors mounted on the vehicle wing, thus enabling an aerodynamically and environmentally clean nose area for atmospheric sensors. A payload bay is also incorporated in the fuselage to accommodate remote sensing instruments. A key feature of this concept is lightweight construction combined with low flying speeds to minimize kinetic energy and associated hazards, as well as maximizing spatial resolution. This type of aerial platform is needed for Earth science research and environmental monitoring. There were no vehicles of this type known to exist previously.

  14. Advanced Image Processing of Aerial Imagery

    NASA Technical Reports Server (NTRS)

    Woodell, Glenn; Jobson, Daniel J.; Rahman, Zia-ur; Hines, Glenn

    2006-01-01

    Aerial imagery of the Earth is an invaluable tool for the assessment of ground features, especially during times of disaster. Researchers at the NASA Langley Research Center have developed techniques which have proven to be useful for such imagery. Aerial imagery from various sources, including Langley's Boeing 757 Aries aircraft, has been studied extensively. This paper discusses these studies and demonstrates that better-than-observer imagery can be obtained even when visibility is severely compromised. A real-time, multi-spectral experimental system will be described and numerous examples will be shown.

  15. Ground cover estimated from aerial photographs

    NASA Technical Reports Server (NTRS)

    Gerbermann, A. H.; Cuellar, J. A.; Wiegand, C. L.

    1976-01-01

    Estimates of per cent ground cover made by ground observers were compared with independent estimates made on the basis of low-altitude (640-1219 m) aerial photographs of the same fields. Standard statistical simple correlation and linear regression analyses revealed a high correlation between the two estimation methods. In crops such as grain, sorghum, corn, and forage sorghum, in which the broadest part of the leaf canopy is near the top of the plant, there was a tendency to overestimate the per cent ground cover from aerial photographs.

  16. Career Profile- Jim Ross, Aerial Photographer

    NASA Image and Video Library

    2016-12-21

    Check out what it takes to “capture the moment” at Mach speeds. The stunning aerial imagery of NASA Armstrong Flight Research Center comes from well-skilled photographers like Jim Ross, Photo Lead. This career profile video highlights Jim’s job responsibilities in documenting aircraft hardware installations, aerial research, and mission work that happens both on center and around the world. During Jim’s 27-year career, he has logged over 800 flight hours in twelve different types of aircraft.

  17. Noise from aerial bursts of fireworks

    NASA Technical Reports Server (NTRS)

    Maglieri, D. J.; Henderson, H. R.

    1973-01-01

    A study was made recording the pressure time histories of the aerial bursts of mortars of various sizes launched during an actual fireworks display. The peak overpressure and duration of blast noise as well as the energy spectral density are compared with the characteristics of a blasting cap and of an F-104 aircraft at a Mach number of 1.4 and an altitude of 42,000 ft. Noise levels of the fireworks aerial bursts peaked 15 decibels below levels deemed damaging to hearing.

  18. Noise from aerial bursts of fireworks

    NASA Technical Reports Server (NTRS)

    Maglieri, D. J.; Henderson, H. R.

    1973-01-01

    A study was made recording the pressure time histories of the aerial bursts of mortars of various sizes launched during an actual fireworks display. The peak overpressure and duration of blast noise as well as the energy spectral density are compared with the characteristics of a blasting cap and of an F-104 aircraft at a Mach number of 1.4 and an altitude of 42,000 ft. Noise levels of the fireworks aerial bursts peaked 15 decibels below levels deemed damaging to hearing.

  19. Laser Doppler velocimeter aerial spray measurements

    NASA Technical Reports Server (NTRS)

    Zalay, A. D.; Eberle, W. R.; Howle, R. E.; Shrider, K. R.

    1978-01-01

    An experimental research program for measuring the location, spatial extent, and relative concentration of airborne spray clouds generated by agricultural aircraft is described. The measurements were conducted with a ground-based laser Doppler velocimeter. The remote sensing instrumentation, experimental tests, and the results of the flight tests are discussed. The cross section of the aerial spray cloud and the observed location, extent, and relative concentration of the airborne particulates are presented. It is feasible to use a mobile laser Doppler velocimeter to track and monitor the transport and dispersion of aerial spray generated by an agricultural aircraft.

  20. 59. AERIAL VIEW OF OWYHEE DAM SHOWING RINGGATE SPILLWAY. VIEW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    59. AERIAL VIEW OF OWYHEE DAM SHOWING RING-GATE SPILLWAY. VIEW TO NORTHEAST. Aerial photo by Glade Walker, U.S. Bureau of Reclamation, Pacific Northwest Region, September 29, 1989. - Owyhee Dam, Across Owyhee River, Nyssa, Malheur County, OR

  1. AERIAL OF VISITORS INFORMATION CENTER [VIC] & ROCKET GARDEN

    NASA Technical Reports Server (NTRS)

    1973-01-01

    AERIAL OF VISITORS INFORMATION CENTER [VIC] & ROCKET GARDEN KSC-373C-0556.20 116-KSC-373C-556.20, P-01622-B, ARCHIVE-04455 Aerial view of Easter crowds at Visitors Information Center, Kennedy Space Center, Florida.

  2. AERIAL OF SHUTTLE LANDING FACILITY [SLF] POURING OF CONCRETE

    NASA Technical Reports Server (NTRS)

    1975-01-01

    AERIAL OF SHUTTLE LANDING FACILITY [SLF] POURING OF CONCRETE KSC-375C-10036.31 108-KSC-375C-10036.31, P-21426, ARCHIVE-04502 Aerial oblique of Shuttle runway facilities. Pouring concrete on runway. Direction north - altitude 100'.

  3. A mass spectrometric analysis of {gamma}-GPS films

    SciTech Connect

    Dillingham, R.G.; Boerio, F.J.; Bertelsen, C.; Savina, M.R.; Lykke, K.R.; Calaway, W.F.

    1996-06-01

    {gamma}-glycidoxypropyltrimethoxysilane ({gamma}-GPS) is used for pre-treatment of grit-blasted aluminum before adhesive bonding. This paper discusses analysis of non-reflective grit-blasted surfaces using mass spectrometry of species that were either sputtered off using an ion beam or thermally desorbed as neutrals using a pulsed laser and then post-ionized using a secondary laser. Results show that fragmentation is excessive and structural information is difficult to obtain from the spectra.

  4. Unmanned Aerial Vehicles DOD’s Acquisition Efforts.

    DTIC Science & Technology

    2007-11-02

    Unmanned Aerial Vehicles : Hunter System Is Not Appropriate for Navy Fleet Use (GAO/NSIAD-96-2, Dec. 1, 1995). Unmanned Aerial Vehicles : Maneuver...System Schedule Includes Unnecessary Risk (GAO/NSIAD-95-161, Sept. 15, 1995). Unmanned Aerial Vehicles : No More Hunter Systems...Should Be Bought Until Problems are Fixed (GAO/NSIAD-95-52, Mar. 1, 1995). Unmanned Aerial Vehicles : Performance of Short-Range System in Question

  5. An aerial radiological survey of the Oyster Creek Nuclear Power Plant and surrounding area, Forked River, New Jersey. Date of survey: September 18--25, 1992

    SciTech Connect

    Hopkins, H.A.; McCall, K.A.

    1994-05-01

    An aerial radiological survey was conducted over the Oyster Creek Nuclear Power Plant in Forked River, New Jersey, during the period September 18 through September 24, 1992. The survey was conducted at an altitude of 150 feet (46 meters) over a 26-square-mile (67-square-kilometer) area centered on the power station. The purpose of the survey was to document the terrestrial gamma radiation environment of the Oyster Creek Nuclear Power plant and surrounding area. The results of the aerial survey are reported as inferred gamma radiation exposure rates at 1 meter above ground level in the form of a contour map. Outside the plant boundary, exposure rates were found to vary between 4 and 10 microroentgens per hour and were attributed to naturally-occurring uranium, thorium, and radioactive potassium gamma emitters. The aerial data were compared to ground-based benchmark exposure rate measurements and radionuclide assays of soil samples obtained within the survey boundary. The ground-based measurements were found to be in good agreement with those inferred from the aerial measuring system. A previous survey of the power plant was conducted in August 1969 during its initial startup phase. Exposure rates and radioactive isotopes revealed in both surveys were consistent and within normal terrestrial background levels.

  6. Spatial distribution of gamma radiation levels in surface soils from Jaduguda uranium mineralization zone, Jharkhand, India, using γ-ray spectrometry, and determination of outdoor dose to the population

    PubMed Central

    Maharana, Mandakini; Krishnan, Narayani; Sengupta, D.

    2010-01-01

    The concentrations of natural radionuclides in surface soil samples around selected villages of Jaduguda were investigated and compared with the radioactivity level in the region. Concentrations of 238U, 232Th, and 40K were determined by a gamma ray spectrometer using the HPGe detector with 50% relative efficiency, and the radiation dose to the local population was estimated. The average estimated activity concentrations of 238U, 232Th, and 40K in the surface soil were 53.8, 44.2 and 464.2 Bq kg−1 respectively. The average absorbed dose rate in the study area was estimated to be 72.5 nGy h-1, where as the annual effective dose to the population was 0.09 mSv y-1. A correlation analysis was made between measured dose rate and individual radionuclides, in order to delineate the contribution of the respective nuclides towards dose rate. The radio-elemental concentrations of uranium, thorium and potassium estimated for the soils, in the study area, indicated the enrichment of uranium series nuclide. The results of the present study were subsequently compared with international and national recommended values. PMID:21170189

  7. Gamma ray generator

    SciTech Connect

    Firestone, Richard B; Reijonen, Jani

    2014-05-27

    An embodiment of a gamma ray generator includes a neutron generator and a moderator. The moderator is coupled to the neutron generator. The moderator includes a neutron capture material. In operation, the neutron generator produces neutrons and the neutron capture material captures at least some of the neutrons to produces gamma rays. An application of the gamma ray generator is as a source of gamma rays for calibration of gamma ray detectors.

  8. System for interactive management of aerial imaging campaigns

    NASA Astrophysics Data System (ADS)

    Wypych, Tom; Kuester, Falko

    We present a system to enable real time management of interchangeable imaging platforms aboard commodity unmanned aerial vehicles (UAVs) to improve interactivity during aerial imaging campaigns. We argue that this improvement in interactivity enables powerful immediate-mode inspection by the ground operator, and implements a more intuitive, flexible, and ultimately useful control interface to aerial imaging systems.

  9. 47 CFR 32.6421 - Aerial cable expense.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Aerial cable expense. 32.6421 Section 32.6421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6421 Aerial cable expense. (a) This account shall include expenses associated with aerial cable. (b) Subsidiary record categories...

  10. 47 CFR 32.6421 - Aerial cable expense.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Aerial cable expense. 32.6421 Section 32.6421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6421 Aerial cable expense. (a) This account shall include expenses associated with aerial cable. (b) Subsidiary record categories...

  11. 47 CFR 32.6421 - Aerial cable expense.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Aerial cable expense. 32.6421 Section 32.6421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6421 Aerial cable expense. (a) This account shall include expenses associated with aerial cable. (b) Subsidiary record categories...

  12. 47 CFR 32.6421 - Aerial cable expense.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Aerial cable expense. 32.6421 Section 32.6421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6421 Aerial cable expense. (a) This account shall include expenses associated with aerial cable. (b) Subsidiary record categories...

  13. 47 CFR 32.6421 - Aerial cable expense.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Aerial cable expense. 32.6421 Section 32.6421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6421 Aerial cable expense. (a) This account shall include expenses associated with aerial cable. (b) Subsidiary record categories...

  14. 47 CFR 32.6431 - Aerial wire expense.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Aerial wire expense. 32.6431 Section 32.6431... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6431 Aerial wire expense. This account shall include expenses associated with aerial wire. ...

  15. Multifunctional aerial display through use of polarization-processing display

    NASA Astrophysics Data System (ADS)

    Uchida, Keitaro; Ito, Shusei; Yamamoto, Hirotsugu

    2017-02-01

    We have realized a multifunctional aerial display. An aerial image of a polarization-processing display is formed through aerial imaging by retro-reflection. By changing the polarization modulation patterns, we can switch between a three-layered display and a secure display.

  16. 47 CFR 32.6431 - Aerial wire expense.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Aerial wire expense. 32.6431 Section 32.6431... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6431 Aerial wire expense. This account shall include expenses associated with aerial wire....

  17. 47 CFR 32.6431 - Aerial wire expense.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Aerial wire expense. 32.6431 Section 32.6431... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6431 Aerial wire expense. This account shall include expenses associated with aerial wire....

  18. 47 CFR 32.6431 - Aerial wire expense.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Aerial wire expense. 32.6431 Section 32.6431... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6431 Aerial wire expense. This account shall include expenses associated with aerial wire....

  19. 47 CFR 32.6431 - Aerial wire expense.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Aerial wire expense. 32.6431 Section 32.6431... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6431 Aerial wire expense. This account shall include expenses associated with aerial wire....

  20. Unmanned Aerial Vehicle Mishap Taxonomy for Range Safety Reviews

    DTIC Science & Technology

    2016-02-01

    RANGE SAFETY GROUP DOCUMENT 326-16 UNMANNED AERIAL VEHICLE MISHAP TAXONOMY FOR RANGE SAFETY REVIEWS DISTRIBUTION A: APPROVED...DOCUMENT 326-16 UNMANNED AERIAL VEHICLE MISHAP TAXONOMY FOR RANGE SAFETY REVIEWS February 2016 Prepared by Range...intentionally left blank. Unmanned Aerial Vehicle Mishap Taxonomy for Range Safety Reviews, RCC 326-16, February 2016 iii Table of Contents Preface

  1. Extreme Agility Micro Aerial Vehicle - Control of Hovering Maneuvers for a Mini-Aerial Vehicle with an Onboard Autopilot System

    DTIC Science & Technology

    2011-02-01

    Extreme Agility Micro Aerial Vehicle - Control of hovering maneuvers for a mini-aerial vehicle with an onboard autopilot system P.-R. Bilodeau AEREX...Micro Aerial Vehicle - Control of hovering maneuvers for a mini-aerial vehicle with an onboard autopilot system P.-R. Bilodeau AEREX Avionique inc...onboard autopilot. The implementation of the controllers on the onboard autopilot reduced system delays observed from an off board controller

  2. An aerial radiological survey of Project Gasbuggy and surrounding area, Rio Arriba County, New Mexico. Date of survey: October 27, 1994

    SciTech Connect

    1995-08-01

    An aerial radiological survey was conducted over the Project Gasbuggy site, 55 miles (89 kilometers) east of Farmington, New Mexico, on October 27, 1994. Parallel lines were flown at intervals of 300 feet (91 meters) over a 16-square-mile (41-square-kilometer) area at a 150-foot (46-meter) altitude centered on the Gasbuggy site. The gamma energy spectra obtained were reduced to an exposure rate contour map overlaid on a high altitude aerial photograph of the area. The terrestrial exposure rate varied from 14 to 20 {micro}R/h at 1 meter above ground level. No anomalous or man-made isotopes were found.

  3. Isolation, chemical and free radical scavenging characterization of phenolics from Trifolium scabrum L. aerial parts.

    PubMed

    Kowalska, Iwona; Jedrejek, Dariusz; Ciesla, Lukasz; Pecio, Lukasz; Masullo, Milena; Piacente, Sonia; Oleszek, Wieslaw; Stochmal, Anna

    2013-05-08

    For the first time Trifolium scabrum L. was researched for its phenolic profile. Sixteen phenolics (isoflavones and flavonoids) were isolated and identified in the aerial parts of T. scabrum L. Their structures were established by electrospray ionization-mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) techniques. Quantitative analysis of individual phenolics performed by means of ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) was based on calibration curves obtained for previously isolated standard compounds. Additionally, the free radical scavenging potential of these substances was assessed by means of a simple benchtop thin-layer chromatography-2,2-diphenyl-1-picrylhydrazyl radical (TLC-DPPH(•)) bioassay. Thus, T. scabrum L. can be regarded as a potential source of estrogenic and antioxidant compounds, both of significance in the pharmaceutical as well as the food industry. The results show that T. scabrum L. can be considered as a natural and very good commercial source of phenolic compounds (mainly isoflavones).

  4. "A" Is for Aerial Maps and Art

    ERIC Educational Resources Information Center

    Todd, Reese H.; Delahunty, Tina

    2007-01-01

    The technology of satellite imagery and remote sensing adds a new dimension to teaching and learning about maps with elementary school children. Just a click of the mouse brings into view some images of the world that could only be imagined a generation ago. Close-up aerial pictures of the school and neighborhood quickly catch the interest of…

  5. Aerial Infrared Photos for Citrus Growers

    NASA Technical Reports Server (NTRS)

    Blazquez, C. H.; Horn, F. W. J.

    1982-01-01

    Handbook advises on benefits and methods of aerial photography with color infrared film. Interpretation of photographs is discussed in detail. Necessary equipment for interpretation is described--light table, magnifying lenses, and microfiche viewers, for example. Advice is given on rating tree condition; identifying effects of diseases, insects, and nematodes; and evaluating effects of soil, water, and weather.

  6. Using Unmanned Aerial Vehicles and GPS Receivers

    NASA Technical Reports Server (NTRS)

    Gary, B.

    1995-01-01

    It is proposed that a small fleet of unmanned aerial vehicles (UAVs) be used over a period of years to monitor the rise of pressure surfaces caused by the hypothesized rise in average temperature of the troposphere due to global warming. Global Positioning Satellite System (GPS) receivers would be used for the precise tracking required.

  7. Aerial view of KSC's Visitor Complex

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This aerial view is of Kennedy Space Center's Visitor Complex. The full-scale replicas of the Space Shuttle external tank, solid rocket boosters and orbiter are located to the left of the various buildings which comprise the complex. The long narrow building in the left foreground is the Center for Space Education which houses the Educators Resource Center and the Astronauts Memorial Foundation.

  8. A TOOL FOR PLANNING AERIAL PHOTOGRAPHY

    EPA Science Inventory

    abstract The U.S. EPAs Pacific Coastal Ecology Branch has developed a tool in the form of an Excel. spreadsheet that facilitates planning aerial photography missions. The spreadsheet accepts various input parameters such as desired photo-scale and boundary coordinates of the stud...

  9. Aerial Infrared Photos for Citrus Growers

    NASA Technical Reports Server (NTRS)

    Blazquez, C. H.; Horn, F. W. J.

    1982-01-01

    Handbook advises on benefits and methods of aerial photography with color infrared film. Interpretation of photographs is discussed in detail. Necessary equipment for interpretation is described--light table, magnifying lenses, and microfiche viewers, for example. Advice is given on rating tree condition; identifying effects of diseases, insects, and nematodes; and evaluating effects of soil, water, and weather.

  10. 47 CFR 32.2431 - Aerial wire.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2431 Aerial wire. (a) This account shall include the original cost of bare line wire and other material used in the construction of such plant. (b) The cost of permits and privileges for the construction of cable and wire...

  11. 29 CFR 1926.453 - Aerial lifts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Qualification Procedure, AWS B3.0-41. (ii) Recommended Practices for Automotive Welding Design, AWS D8.4-61... 22, 1973 shall be designed and constructed in conformance with the applicable requirements of the... conform with the applicable design and construction requirements of ANSI A92.2-1969. Aerial lifts include...

  12. 29 CFR 1926.453 - Aerial lifts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Qualification Procedure, AWS B3.0-41. (ii) Recommended Practices for Automotive Welding Design, AWS D8.4-61... 22, 1973 shall be designed and constructed in conformance with the applicable requirements of the... conform with the applicable design and construction requirements of ANSI A92.2-1969. Aerial lifts include...

  13. Sea Ice Mapping using Unmanned Aerial Systems

    NASA Astrophysics Data System (ADS)

    Solbø, S.; Storvold, R.

    2011-12-01

    Mapping of sea ice extent and sea ice features is an important task in climate research. Since the arctic coastal and oceanic areas have a high probability of cloud coverage, aerial platforms are superior to satellite measurements for high-resolution optical measurements. However, routine observations of sea ice conditions present a variety of problems using conventional piloted aircrafts. Specially, the availability of suitable aircrafts for lease does not cover the demand in major parts of the arctic. With the recent advances in unmanned aerial systems (UAS), there is a high possibility of establishing routine, cost effective aerial observations of sea ice conditions in the near future. Unmanned aerial systems can carry a wide variety of sensors useful for characterizing sea-ice features. For instance, the CryoWing UAS, a system initially designed for measurements of the cryosphere, can be equipped with digital cameras, surface thermometers and laser altimeters for measuring freeboard of ice flows. In this work we will present results from recent CryoWing sea ice flights on Svalbard, Norway. The emphasis will be on data processing for stitching together images acquired with the non-stabilized camera payload, to form high-resolution mosaics covering large spatial areas. These data are being employed to map ice conditions; including ice and lead features and melt ponds. These high-resolution mosaics are also well suited for sea-ice mechanics, classification studies and for validation of satellite sea-ice products.

  14. Converting aerial imagery to application maps

    USDA-ARS?s Scientific Manuscript database

    Over the last couple of years in Agricultural Aviation and at the 2014 and 2015 NAAA conventions, we have written about and presented both single-camera and two-camera imaging systems for use on agricultural aircraft. Many aerial applicators have shown a great deal of interest in the imaging systems...

  15. The Art and Science of Aerial Perspective

    ERIC Educational Resources Information Center

    Kegel, Susan

    2006-01-01

    The author is always looking for ways to see connections and to adapt experiences across different subjects. Combining art with other disciplines helps keep students engaged, even the really analytical and verbal learners. Aerial perspective is an art technique, a scientific principle, and a vehicle for introducing Chinese painting and…

  16. A short cut for scaling aerial photos

    Treesearch

    Earl J. Rogers

    1948-01-01

    Aerial photos are a handy tool for the forester. They furnish forest data quickly. But when the photo is used as a map, care is necessary - especially in rough country. In flat country photo scales are quite uniform and distances can be measured accurately. But in rough country photo scale varies with changes in elevation, and it is more difficult to measure distances...

  17. Using Unmanned Aerial Vehicles and GPS Receivers

    NASA Technical Reports Server (NTRS)

    Gary, B.

    1995-01-01

    It is proposed that a small fleet of unmanned aerial vehicles (UAVs) be used over a period of years to monitor the rise of pressure surfaces caused by the hypothesized rise in average temperature of the troposphere due to global warming. Global Positioning Satellite System (GPS) receivers would be used for the precise tracking required.

  18. "A" Is for Aerial Maps and Art

    ERIC Educational Resources Information Center

    Todd, Reese H.; Delahunty, Tina

    2007-01-01

    The technology of satellite imagery and remote sensing adds a new dimension to teaching and learning about maps with elementary school children. Just a click of the mouse brings into view some images of the world that could only be imagined a generation ago. Close-up aerial pictures of the school and neighborhood quickly catch the interest of…

  19. A TOOL FOR PLANNING AERIAL PHOTOGRAPHY

    EPA Science Inventory

    abstract The U.S. EPAs Pacific Coastal Ecology Branch has developed a tool in the form of an Excel. spreadsheet that facilitates planning aerial photography missions. The spreadsheet accepts various input parameters such as desired photo-scale and boundary coordinates of the stud...

  20. Aerial Scene Recognition using Efficient Sparse Representation

    SciTech Connect

    Cheriyadat, Anil M

    2012-01-01

    Advanced scene recognition systems for processing large volumes of high-resolution aerial image data are in great demand today. However, automated scene recognition remains a challenging problem. Efficient encoding and representation of spatial and structural patterns in the imagery are key in developing automated scene recognition algorithms. We describe an image representation approach that uses simple and computationally efficient sparse code computation to generate accurate features capable of producing excellent classification performance using linear SVM kernels. Our method exploits unlabeled low-level image feature measurements to learn a set of basis vectors. We project the low-level features onto the basis vectors and use simple soft threshold activation function to derive the sparse features. The proposed technique generates sparse features at a significantly lower computational cost than other methods~\\cite{Yang10, newsam11}, yet it produces comparable or better classification accuracy. We apply our technique to high-resolution aerial image datasets to quantify the aerial scene classification performance. We demonstrate that the dense feature extraction and representation methods are highly effective for automatic large-facility detection on wide area high-resolution aerial imagery.

  1. Projection-viewer for microscale aerial photography

    Treesearch

    Robert C. Aldrich; James von Mosch; Wallace Greentree

    1972-01-01

    A low-cost projection-viewer has been developed to enlarge portions of microscale aerial photographs. These pictures can be used for interpretation or mapping, or for comparison with existing photographs, maps, and overlays to monitor environmental changes. The projection-viewer can enlarge from 2.5 to 20 times, and can be calibrated so that maps may be drawn with a...

  2. 47 CFR 32.2421 - Aerial cable.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the original cost of single or paired conductor cable, wire and other associated material used in... cable or aerial wire as well as the cost of other material used in construction of such plant... cost of optical fiber cable and other associated material used in constructing a physical path for...

  3. An Aerial Radiological Survey of the Portsmouth Gaseous Diffusion Plant and Surrounding Area, Portsmouth, Ohio

    SciTech Connect

    Namdoo Moon

    2007-12-01

    An aerial radiological survey was conducted over the 16 square-mile (~41 square-kilometer) area surrounding the Portsmouth Gaseous Diffusion Plant. The survey was performed in August 2007 utilizing a large array of helicopter mounted sodium iodide detectors. The purpose of the survey was to update the previous radiological survey levels of the environment and surrounding areas of the plant. A search for a missing radium-226 source was also performed. Implied exposure rates, man-made activity, and excess bismuth-214 activity, as calculated from the aerial data are presented in the form of isopleth maps superimposed on imagery of the surveyed area. Ground level and implied aerial exposure rates for nine specific locations are compared. Detected radioisotopes and their associated gamma ray exposure rates were consistent with those expected from normal background emitters. At specific plant locations described in the report, man-made activity was consistent with the operational histories of the location. There was no spectral activity that would indicate the presence of the lost source.

  4. Rapid In-Situ Measurement of Gamma Activity in Soil for Environmental Assessment

    NASA Astrophysics Data System (ADS)

    Honeycutt, T. K.

    2003-12-01

    In-situ measurements of gamma radiation in soil are used as a rapid, low-cost, non-intrusive alternative to conventional sampling and analysis methods in the preliminary assessment of environmental impacts to watersheds at the Savannah River Site (SRS). The method resolves the ambient gamma-radiation field near ground surface into background and residual components and provides radionuclide-specific soil activity determination. The efficacy of the method has been evaluated and compares favorably with conventional gamma-PHA soil analyses and aerial survey data. The method has garnered regulatory approval and is being successfully deployed to evaluate the impact of Cs-137 contamination from CERCLA sites.

  5. The gamma-ray telescope Gamma-1

    NASA Technical Reports Server (NTRS)

    Akimov, V. V.; Nesterov, V. E.; Kalinkin, L. F.; Balibanov, V. M.; Prilutsky, O. F.; Rodin, V. G.; Leikov, N. G.; Bielaoussov, A. S.; Dobrian, L. B.; Poluektov, V. P.

    1985-01-01

    French and Soviet specialists have designed and built the gamma-ray telescope GAMMA-1 to detect cosmic gamma rays above 50 MeV. The sensitive area of the detector is 1400 sq cm, energy resolution is 30% at 300 MeV, and angular resolution 1.2 deg at 300 MeV (and less than 20' arc when a coded aperture mask is used). Results on calibration of the qualification model and Monte-Carlo calculations are presented.

  6. Object and activity detection from aerial video

    NASA Astrophysics Data System (ADS)

    Se, Stephen; Shi, Feng; Liu, Xin; Ghazel, Mohsen

    2015-05-01

    Aerial video surveillance has advanced significantly in recent years, as inexpensive high-quality video cameras and airborne platforms are becoming more readily available. Video has become an indispensable part of military operations and is now becoming increasingly valuable in the civil and paramilitary sectors. Such surveillance capabilities are useful for battlefield intelligence and reconnaissance as well as monitoring major events, border control and critical infrastructure. However, monitoring this growing flood of video data requires significant effort from increasingly large numbers of video analysts. We have developed a suite of aerial video exploitation tools that can alleviate mundane monitoring from the analysts, by detecting and alerting objects and activities that require analysts' attention. These tools can be used for both tactical applications and post-mission analytics so that the video data can be exploited more efficiently and timely. A feature-based approach and a pixel-based approach have been developed for Video Moving Target Indicator (VMTI) to detect moving objects at real-time in aerial video. Such moving objects can then be classified by a person detector algorithm which was trained with representative aerial data. We have also developed an activity detection tool that can detect activities of interests in aerial video, such as person-vehicle interaction. We have implemented a flexible framework so that new processing modules can be added easily. The Graphical User Interface (GUI) allows the user to configure the processing pipeline at run-time to evaluate different algorithms and parameters. Promising experimental results have been obtained using these tools and an evaluation has been carried out to characterize their performance.

  7. GRABGAM Analysis of Ultra-Low-Level HPGe Gamma Spectra

    SciTech Connect

    Winn, W.G.

    1999-07-28

    The GRABGAM code has been used successfully for ultra-low level HPGe gamma spectrometry analysis since its development in 1985 at Savannah River Technology Center (SRTC). Although numerous gamma analysis codes existed at that time, reviews of institutional and commercial codes indicated that none addressed all features that were desired by SRTC. Furthermore, it was recognized that development of an in-house code would better facilitate future evolution of the code to address SRTC needs based on experience with low-level spectra. GRABGAM derives its name from Gamma Ray Analysis BASIC Generated At MCA/PC.

  8. An aerial radiological survey of the Davis-Monthan Air Force Base and surrounding area, Tucson, Arizona

    SciTech Connect

    1995-09-01

    An aerial radiological survey, which was conducted from March 1 to 13, 1995, covered a 51-square-mile (132-square-kilometer) area centered on the Davis-Monthan Air Force Base (DMAFB) in Tucson, Arizona. The results of the survey are reported as contours of bismuth-214 ({sup 214}Bi) soil concentrations, which are characteristic of natural uranium and its progeny, and as contours of the total terrestrial exposure rates extrapolated to one meter above ground level. All data were scaled and overlaid on an aerial photograph of the DMAFB area. The terrestrial exposure rates varied from 9 to 20 microroentgens per hour at one meter above the ground. Elevated levels of terrestrial radiation due to increased concentrations of {sup 214}Bi (natural uranium) were observed over the Southern Pacific railroad yard and along portions of the railroad track bed areas residing both within and outside the base boundaries. No man-made, gamma ray-emitting radioactive material was observed by the aerial survey. High-purity germanium spectrometer and pressurized ionization chamber measurements at eight locations within the base boundaries were used to verify the integrity of the aerial results. The results of the aerial and ground-based measurements were found to be in agreement. However, the ground-based measurements were able to detect minute quantities of cesium-137 ({sup 137}Cs) at six of the eight locations examined. The presence of {sup 137}Cs is a remnant of fallout from foreign and domestic atmospheric nuclear weapons testing that occurred in the 1950s and early 1960s. Cesium-137 concentrations varied from 0.1 to 0.3 picocuries per gram, which is below the minimum detectable activity of the aerial system.

  9. Recent progress in low-level gamma imaging

    SciTech Connect

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

    2007-07-01

    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 {gamma} 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. An aerial radiological survey of the neutron products company and surrounding area

    SciTech Connect

    Vojtech, R.J.

    1994-12-01

    An aerial radiological survey was conducted from November 1-10, 1993, over the Neutron Products Company and neighboring areas. The company, located in Dickerson, Maryland, has two major operations involving the radioisotope cobalt-60 ({sup 60}Co)-the manufacture of commercial {sup 60}Co sources and the sterilization of medical products by exposure to radiation. The sterilization facility consists of two {sup 60}Co sources with activities of approximately 500,000 and 1,500,000 Ci, respectively. The purpose of the aerial survey was to detect and document any anomalous gamma-emitting radionuclides in the environment which may have resulted from operations of the Neutron Products Company. The survey covered two areas: the first was a 6.5- by 6.5-kilometer area centered over the Neutron Products facility; the second area was a 2- by 2.5-kilometer region surrounding a waste pumping station on Muddy Branch in Gaithersburg, Maryland. This site is approximately fifteen kilometers southeast of the Neutron Products facility and was included because sanitary and other liquid waste materials from the plant site are being disposed of at the pumping station. Contour maps showing gamma radiation exposure rates at 1 meter above ground level, overlaid on an aerial photo of the area, were constructed from the data measured during the flights. The exposure rates measured within the survey regions were generally uniform and typical of rates resulting from natural background radiation. Only one area showed an enhanced exposure rate not attributable to natural background. This area, located directly over the Neutron Products facility, was analyzed and identified as {sup 60}Co, the radioisotope used in the irradiation and source production operations conducted at the Neutron Products Company. The measurements over the Muddy Branch area in Gaithersburg were typical of natural background radiation and showed no evidence of {sup 60}Co or any other man-made radionuclide.

  11. Application of nondestructive gamma-ray and neutron techniques for the safeguarding of irradiated fuel materials

    SciTech Connect

    Phillips, J.R.; Halbig, J.K.; Lee, D.M.; Beach, S.E.; Bement, T.R.; Dermendjiev, E.; Hatcher, C.R.; Kaieda, K.; Medina, E.G.

    1980-05-01

    Nondestructive gamma-ray and neutron techniques were used to characterize the irradiation exposures of irradiated fuel assemblies. Techniques for the rapid measurement of the axial-activity profiles of fuel assemblies have been developed using ion chambers and Be(..gamma..,n) detectors. Detailed measurements using high-resolution gamma-ray spectrometry and passive neutron techniques were correlated with operator-declared values of cooling times and burnup.

  12. gamma-Hexachlorocyclohexane (gamma-HCH)

    Integrated Risk Information System (IRIS)

    gamma - Hexachlorocyclohexane ( gamma - HCH ) ; CASRN 58 - 89 - 9 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Asse

  13. An aerial radiological survey of the Evans Area, US Army Communications-Electronics Command, Fort Monmouth, New Jersey

    SciTech Connect

    Maurer, R.J.

    1989-12-01

    An aerial radiological survey was conducted over the Evans Area, US Army Communications-Electronics Command, Fort Monmouth, New Jersey, during the period November 14--18, 1988. The purposes of the survey were to document the terrestrial gamma environment of the Evans site and surrounding area and to determine if there had been any radiological impact on the area due to past laboratory operations. The results of the aerial survey are reported as inferred radiation exposure rates at 1 meter above ground level in the form of a contour map. The aerial data were compared to ground-based benchmark'' exposure rate measurements and radionuclide assay of soil samples obtained at sites outside the survey perimeter. Similar ground-based measurements were also made at several locations on the Evans site and at the bank of the Shark River bordering the Evans Area. No evidence for contamination was identified by either radionuclide assay of soil samples or the aerial survey. 6 refs., 5 figs., 2 tabs.

  14. A simple gamma ray direction finder.

    PubMed

    Fujimoto, K

    2006-07-01

    One of the simplest gamma spectrometry systems that could provide the directional information of incident gamma rays has been developed. The system consists of a 3'' x 3'' phi NaI (Tl) scintillator, a specially shaped lead shield, and software. The measurement was carried out four times by rotating the shield position along the axis of the detector to obtain four energy spectra at one location. Four count rates at a special region of interest in the spectra were fed into the software for determining incident directions of gamma rays. Experiments using (137)Cs and (54)Mn at the same time demonstrated that the direction of gamma rays from several dominant sources from any direction could be identified with good precision by the total measurement time of 10 to 20 min. The system could be used to identify the locations of missing radioactive sources or the cause of elevation in ambient radiation dose rates. The disadvantages of the present system are follows: (1) It requires four time measurements at one location; (2) It can provide one pseudo incident angle when several contamination sources exist around the detector system and emit the same energy gamma rays; and (3) It can scan only one plane geometry that is usually chosen as the horizontal plane.

  15. Gamma ray detector shield

    DOEpatents

    Ohlinger, R.D.; Humphrey, H.W.

    1985-08-26

    A gamma ray detector shield comprised of a rigid, lead, cylindrical-shaped vessel having upper and lower portions with an pneumatically driven, sliding top assembly. Disposed inside the lead shield is a gamma ray scintillation crystal detector. Access to the gamma detector is through the sliding top assembly.

  16. Aerial color infrared photography applications to citriculture

    NASA Technical Reports Server (NTRS)

    Blazquez, C. H.; Horn, F. W., Jr.

    1980-01-01

    Results of a one-year experimental study on the use of aerial color infrared photography in citrus grove management are presented. It is found that the spring season, when trees are in flush (have young leaves), is the best season to photograph visible differences between healthy and diseased trees. It is also shown that the best photography can be obtained with a 12-in. focal length lens. The photographic scale that allowed good photo interpretation with simple inexpensive equipment was 1 in. = 330 ft. The use of a window-overlay transparency method allowed rapid photo interpretation and data recording in computer-compatible forms. Aerial color infrared photography carried out during the spring season revealed a more accurate status of tree condition than visual inspection.

  17. Locating waterfowl observations on aerial surveys

    USGS Publications Warehouse

    Butler, W.I.; Hodges, J.I.; Stehn, R.A.

    1995-01-01

    We modified standard aerial survey data collection to obtain the geographic location for each waterfowl observation on surveys in Alaska during 1987-1993. Using transect navigation with CPS (global positioning system), data recording on continuously running tapes, and a computer data input program, we located observations with an average deviation along transects of 214 m. The method provided flexibility in survey design and data analysis. Although developed for geese nesting near the coast of the Yukon-Kuskokwim Delta, the methods are widely applicable and were used on other waterfowl surveys in Alaska to map distribution and relative abundance of waterfowl. Accurate location data with GIS analysis and display may improve precision and usefulness of data from any aerial transect survey.

  18. Aerial color infrared photography applications to citriculture

    NASA Technical Reports Server (NTRS)

    Blazquez, C. H.; Horn, F. W., Jr.

    1980-01-01

    Results of a one-year experimental study on the use of aerial color infrared photography in citrus grove management are presented. It is found that the spring season, when trees are in flush (have young leaves), is the best season to photograph visible differences between healthy and diseased trees. It is also shown that the best photography can be obtained with a 12-in. focal length lens. The photographic scale that allowed good photo interpretation with simple inexpensive equipment was 1 in. = 330 ft. The use of a window-overlay transparency method allowed rapid photo interpretation and data recording in computer-compatible forms. Aerial color infrared photography carried out during the spring season revealed a more accurate status of tree condition than visual inspection.

  19. An aerial radiological survey of the Tonopah Test Range including Clean Slate 1,2,3, Roller Coaster, decontamination area, Cactus Springs Ranch target areas. Central Nevada

    SciTech Connect

    Proctor, A.E.; Hendricks, T.J.

    1995-08-01

    An aerial radiological survey was conducted of major sections of the Tonopah Test Range (TTR) in central Nevada from August through October 1993. The survey consisted of aerial measurements of both natural and man-made gamma radiation emanating from the terrestrial surface. The initial purpose of the survey was to locate depleted uranium (detecting {sup 238}U) from projectiles which had impacted on the TTR. The examination of areas near Cactus Springs Ranch (located near the western boundary of the TTR) and an animal burial area near the Double Track site were secondary objectives. When more widespread than expected {sup 241}Am contamination was found around the Clean Slates sites, the survey was expanded to cover the area surrounding the Clean Slates and also the Double Track site. Results are reported as radiation isopleths superimposed on aerial photographs of the area.

  20. Comparative Analysis of the Tour Jete and Aerial with Detailed Analysis of Aerial Takeoff Mechanics

    NASA Astrophysics Data System (ADS)

    Pierson, Mimi; Coplin, Kim

    2006-10-01

    Whether internally as muscle tension or from external sources, forces are necessary for all motion. This research focused on athletic rotations where conditions of flight are established during takeoff. By studying reaction forces that produce torques, moments of inertia, and linear and angular differences between distinct rotations around different principle axes of the body (tour jete in ballet - longitudinal axis; aerial in gymnastics - anteroposterior axis), and by looking at the values of angular momentum in the specific mechanics of aerial takeoff, we can gain insight into possible causes of injury, flaws in technique and limitations of athletes. Results showed significant differences in the horizontal and vertical components of takeoff between the tour jete and the aerial, and a realization that torque was produced in different biomechanical planes. Both rotations showed braking forces before takeoff to counteract forward momentum and increase vertical lift, but the angle of applied force varied, and the horizontal components of velocity and force and vertical velocity as well as moment of inertia throughout flight were consistently greater for the aerial. Breakdown of aerial takeoff highlighted the relative importance of the takeoff phases, showing that completion depends fundamentally upon the rotation of the rear foot and torso twisting during takeoff rather than the last foot in contact with the ground.

  1. Aerial view of Johnson Space Center

    NASA Image and Video Library

    1990-09-07

    S90-47653 (7 Sept. 1990) --- This aerial photograph of NASA's Johnson Space Center includes the entire 1625-acre site with the exception of a few security-associated facilities and part of the Manned Space Flight Exhibit Complex (AKA "Rocket Park"). The bottom half of the image includes many business and residential edifices as well as a hospital and other medical facilities in the Nassau Bay community. Photo credit: NASA

  2. U.S. Unmanned Aerial Systems

    DTIC Science & Technology

    2012-01-03

    decades for crop dusting and other agricultural purposes.84 Historically, UAS were predominately operated by DoD in support of combat operations in...advocates state that in order for UAS to take an active role in homeland security, law enforcement, aerial surveying, crop dusting, and other...isn’t ready for.93 The issue of when and how UAS will be allowed to operate in U.S. airspace continues to evolve, and continues to be of interest

  3. Ultralight photovoltaic modules for unmanned aerial vehicles

    SciTech Connect

    Nowlan, M.J.; Maglitta, J.C.; Darkazalli, G.; Lamp, T.

    1997-12-31

    New lightweight photovoltaic modules are being developed for powering high altitude unmanned aerial vehicles (UAVs). Modified low-cost terrestrial solar cell and module technologies are being applied to minimize vehicle cost. New processes were developed for assembling thin solar cells, encapsulant films, and cover films. An innovative by-pass diode mounting approach that uses a solar cell as a heat spreader was devised and tested. Materials and processes will be evaluated through accelerated environmental testing.

  4. Aerial vehicles collision avoidance using monocular vision

    NASA Astrophysics Data System (ADS)

    Balashov, Oleg; Muraviev, Vadim; Strotov, Valery

    2016-10-01

    In this paper image-based collision avoidance algorithm that provides detection of nearby aircraft and distance estimation is presented. The approach requires a vision system with a single moving camera and additional information about carrier's speed and orientation from onboard sensors. The main idea is to create a multi-step approach based on a preliminary detection, regions of interest (ROI) selection, contour segmentation, object matching and localization. The proposed algorithm is able to detect small targets but unlike many other approaches is designed to work with large-scale objects as well. To localize aerial vehicle position the system of equations relating object coordinates in space and observed image is solved. The system solution gives the current position and speed of the detected object in space. Using this information distance and time to collision can be estimated. Experimental research on real video sequences and modeled data is performed. Video database contained different types of aerial vehicles: aircrafts, helicopters, and UAVs. The presented algorithm is able to detect aerial vehicles from several kilometers under regular daylight conditions.

  5. Orientation Strategies for Aerial Oblique Images

    NASA Astrophysics Data System (ADS)

    Wiedemann, A.; Moré, J.

    2012-07-01

    Oblique aerial images become more and more distributed to fill the gap between vertical aerial images and mobile mapping systems. Different systems are on the market. For some applications, like texture mapping, precise orientation data are required. One point is the stable interior orientation, which can be achieved by stable camera systems, the other a precise exterior orientation. A sufficient exterior orientation can be achieved by a large effort in direct sensor orientation, whereas minor errors in the angles have a larger effect than in vertical imagery. The more appropriate approach is by determine the precise orientation parameters by photogrammetric methods using an adapted aerial triangulation. Due to the different points of view towards the object the traditional aerotriangulation matching tools fail, as they produce a bunch of blunders and require a lot of manual work to achieve a sufficient solution. In this paper some approaches are discussed and results are presented for the most promising approaches. We describe a single step approach with an aerotriangulation using all available images; a two step approach with an aerotriangulation only of the vertical images plus a mathematical transformation of the oblique images using the oblique cameras excentricity; and finally the extended functional model for a bundle block adjustment considering the mechanical connection between vertical and oblique images. Beside accuracy also other aspects like efficiency and required manual work have to be considered.

  6. Localization of aerial broadband noise by pinnipeds.

    PubMed

    Holt, Marla M; Schusterman, Ronald J; Southall, Brandon L; Kastak, David

    2004-05-01

    Although many pinnipeds (seals, sea lions, and walruses) emit broadband calls on land as part of their communication system, few studies have addressed these animals' ability to localize aerial broadband sounds. In this study, the aerial sound localization acuities of a female northern elephant seal (Mirounga angustirostris), a male harbor seal (Phoca vitulina), and a female California sea lion (Zalophus californianus) were measured in the horizontal plane. The stimulus was broadband white noise that was band pass filtered between 1.2 and 15 kHz. Testing was conducted in a hemi-anechoic chamber using a left/right forced choice procedure to measure the minimum audible angle (MAA) for each subject. MAAs were defined as half the angular separation of two sound sources bisected by a subject's midline that corresponded to 75% correct discrimination. MAAs were 4.7 degrees, 3.6 degrees, and 4.2 degrees for the northern elephant seal, harbor seal, and California sea lion, respectively. These results demonstrate that individuals of these pinniped species have sound localization abilities comparable to the domestic cat and rhesus macaque. The acuity differences between our subjects were small and not predicted by head size. These results likely reflect the relatively acute general abilities of pinnipeds to localize aerial broadband signals.

  7. Remotely deployable aerial inspection using tactile sensors

    NASA Astrophysics Data System (ADS)

    MacLeod, C. N.; Cao, J.; Pierce, S. G.; Sullivan, J. C.; Pipe, A. G.; Dobie, G.; Summan, R.

    2014-02-01

    For structural monitoring applications, the use of remotely deployable Non-Destructive Evaluation (NDE) inspection platforms offer many advantages, including improved accessibility, greater safety and reduced cost, when compared to traditional manual inspection techniques. The use of such platforms, previously reported by researchers at the University Strathclyde facilitates the potential for rapid scanning of large areas and volumes in hazardous locations. A common problem for both manual and remote deployment approaches lies in the intrinsic stand-off and surface coupling issues of typical NDE probes. The associated complications of these requirements are obviously significantly exacerbated when considering aerial based remote inspection and deployment, resulting in simple visual techniques being the preferred sensor payload. Researchers at Bristol Robotics Laboratory have developed biomimetic tactile sensors modelled on the facial whiskers (vibrissae) of animals such as rats and mice, with the latest sensors actively sweeping their tips across the surface in a back and forth motion. The current work reports on the design and performance of an aerial inspection platform and the suitability of tactile whisking sensors to aerial based surface monitoring applications.

  8. Localization of aerial broadband noise by pinnipeds

    NASA Astrophysics Data System (ADS)

    Holt, Marla M.; Schusterman, Ronald J.; Southall, Brandon L.; Kastak, David

    2004-05-01

    Although many pinnipeds (seals, sea lions, and walruses) emit broadband calls on land as part of their communication system, few studies have addressed these animals' ability to localize aerial broadband sounds. In this study, the aerial sound localization acuities of a female northern elephant seal (Mirounga angustirostris), a male harbor seal (Phoca vitulina), and a female California sea lion (Zalophus californianus) were measured in the horizontal plane. The stimulus was broadband white noise that was band pass filtered between 1.2 and 15 kHz. Testing was conducted in a hemi-anechoic chamber using a left/right forced choice procedure to measure the minimum audible angle (MAA) for each subject. MAAs were defined as half the angular separation of two sound sources bisected by a subject's midline that corresponded to 75% correct discrimination. MAAs were 4.7°, 3.6°, and 4.2° for the northern elephant seal, harbor seal, and California sea lion, respectively. These results demonstrate that individuals of these pinniped species have sound localization abilities comparable to the domestic cat and rhesus macaque. The acuity differences between our subjects were small and not predicted by head size. These results likely reflect the relatively acute general abilities of pinnipeds to localize aerial broadband signals.

  9. Mask degradation monitoring with aerial mask inspector

    NASA Astrophysics Data System (ADS)

    Tseng, Wen-Jui; Fu, Yung-Ying; Lu, Shih-Ping; Jiang, Ming-Sian; Lin, Jeffrey; Wu, Clare; Lifschitz, Sivan; Tam, Aviram

    2013-06-01

    As design rule continues to shrink, microlithography is becoming more challenging and the photomasks need to comply with high scanner laser energy, low CDU, and ever more aggressive RETs. This give rise to numerous challenges in the semiconductor wafer fabrication plants. Some of these challenges being contamination (mainly haze and particles), mask pattern degradation (MoSi oxidation, chrome migration, etc.) and pellicle degradation. Fabs are constantly working to establish an efficient methodology to manage these challenges mainly using mask inspection, wafer inspection, SEM review and CD SEMs. Aerial technology offers a unique opportunity to address the above mask related challenges using one tool. The Applied Materials Aera3TM system has the inherent ability to inspect for defects (haze, particles, etc.), and track mask degradation (e.g. CDU). This paper focuses on haze monitoring, which is still a significant challenge in semiconductor manufacturing, and mask degradation effects that are starting to emerge as the next challenge for high volume semiconductor manufacturers. The paper describes Aerial inspector (Aera3) early haze methodology and mask degradation tracking related to high volume manufacturing. These will be demonstrated on memory products. At the end of the paper we take a brief look on subsequent work currently conducted on the more general issue of photo mask degradation monitoring by means of an Aerial inspector.

  10. Inertial instrument system for aerial surveying

    USGS Publications Warehouse

    Brown, R.H.; Chapman, W.H.; Hanna, W.F.; Mongan, C.E.; Hursh, J.W.

    1985-01-01

    An inertial guidance system for aerial surveying has been developed under contract to the U.S. Geological Survey. This prototype system, known as the aerial profiling of terrain (APT) system, is designed to determine continuously the positions of points along an aircraft flight path, or the underlying terrain profile, to an accuracy of + or - 0.5 ft (15 cm) vertically and + or - 2 ft (61 cm) horizontally. The system 's objective thus is to accomplish, from a fixed-wing aircraft, what would traditionally be accomplished from ground-based topographic surveys combined with aerial photography and photogrammetry. The two-part strategy for measuring the terrain profile entails: (1) use of an inertial navigator for continuous determination of the three-coordinate position of the aircraft, and (2) use of an eye-safe pulsed laser profiler for continuous measurement of the vertical distance from aircraft to land surface, so that the desired terrain profile can then be directly computed. The APT system, installed in a DeHavilland Twin Otter aircraft, is typically flown at a speed of 115 mph (105 knots) at an altitude of 2,000 ft (610 m) above the terrain. Performance-evaluation flights have shown that the vertical and horizontal accuracy specifications are met. (USGS)

  11. Remotely deployable aerial inspection using tactile sensors

    SciTech Connect

    MacLeod, C. N.; Cao, J.; Pierce, S. G.; Dobie, G.; Summan, R.; Sullivan, J. C.; Pipe, A. G.

    2014-02-18

    For structural monitoring applications, the use of remotely deployable Non-Destructive Evaluation (NDE) inspection platforms offer many advantages, including improved accessibility, greater safety and reduced cost, when compared to traditional manual inspection techniques. The use of such platforms, previously reported by researchers at the University Strathclyde facilitates the potential for rapid scanning of large areas and volumes in hazardous locations. A common problem for both manual and remote deployment approaches lies in the intrinsic stand-off and surface coupling issues of typical NDE probes. The associated complications of these requirements are obviously significantly exacerbated when considering aerial based remote inspection and deployment, resulting in simple visual techniques being the preferred sensor payload. Researchers at Bristol Robotics Laboratory have developed biomimetic tactile sensors modelled on the facial whiskers (vibrissae) of animals such as rats and mice, with the latest sensors actively sweeping their tips across the surface in a back and forth motion. The current work reports on the design and performance of an aerial inspection platform and the suitability of tactile whisking sensors to aerial based surface monitoring applications.

  12. Rehabilitation of gamma

    NASA Astrophysics Data System (ADS)

    Poynton, Charles A.

    1998-07-01

    Gamma characterizes the reproduction of tone scale in an imaging system. Gamma summarizes, in a single numerical parameter, the nonlinear relationship between code value--in an 8-bit system, from 0 through 255--and physical intensity. Nearly all image coding systems are nonlinear, and so involve values of gamma different from unity. Owing to poor understanding of tone scale reproduction, and to misconceptions about nonlinear coding, gamma has acquired a terrible reputation in computer graphics and image processing. In addition, the world-wide web suffers from poor reproduction of grayscale and color images, due to poor handling of nonlinear image coding. This paper aims to make gamma respectable again.

  13. Gamma-ray waveguides

    SciTech Connect

    Tournear, D. M.; Hoffbauer, M. A.; Akhadov, E. A.; Chen, A. T.; Pendleton, S. J.; Williamson, T. L.; Cha, K. C.; Epstein, R. I.

    2008-04-14

    We have developed an approach for gamma-ray optics using layered structures acting as planar waveguides. Experiments demonstrating channeling of 122 keV gamma rays in two prototype waveguides validate the feasibility of this technology. Gamma-ray waveguides allow one to control the direction of radiation up to a few MeV. The waveguides are conceptually similar to polycapillary optics, but can function at higher gamma-ray energies. Optics comprised of these waveguides will be able to collect radiation from small solid angles or concentrate radiation into small area detectors. Gamma-ray waveguides may find applications in medical imaging and treatment, astrophysics, and homeland security.

  14. An aerial radiological survey of the former Chemetron factory site and surrounding area, Newburgh Heights, Ohio. Date of survey: April 1991

    SciTech Connect

    1992-04-01

    An aerial radiological survey was conducted during the period April 15--27, 1991, over an area surrounding the former location of a Chemetron Corporation factory and an associated disposal site. The area surveyed is situated in Newburgh Heights, Ohio, 3 kilometers south of Cleveland, Ohio. The purpose of the survey was to measure and document the gamma ray environment of the former factory and dump site and surrounding area. Contour maps showing gamma radiation exposure rates at 1 meter above ground level were constructed from the aerial data and overlaid on an aerial photograph of the area. The exposure rates measured within the survey region were generally uniform and typical of natural background: 3--7 microroentgens per hour ({mu}R/h), excluding an estimated cosmic ray contribution of 3.6 {mu}R/h. Enhanced exposure rates not attributable to natural background were measured over three areas within the survey region. Two areas, both within the boundary of a sewage processing plant, showed evidence of cobalt-60 ({sup 60}CO). A third area, measured over a chemical factory, showed evidence of thorium-232 ({sup 232}Th). Radionuclide assays of soil samples and pressurized ionization chamber measurements were obtained at seven locations within the survey boundaries. These measurements are in agreement with the aerial data.

  15. Unmanned Aerial Vehicles: Background and Issues for Congress

    DTIC Science & Technology

    2005-11-21

    Congressional Research Service ˜ The Library of Congress CRS Report for Congress Received through the CRS Web Order Code RL31872 Unmanned Aerial Vehicles : Background...00-2005 4. TITLE AND SUBTITLE Unmanned Aerial Vehicles : Background and Issues for Congress 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Unmanned Aerial Vehicles : Background and

  16. Unmanned Aerial Systems: Quality As Well As Quantity

    DTIC Science & Technology

    2010-08-01

    effectiveness of unmanned aerial system coverage for troops on the ground. The same report also recommended that DOD develop a systematic process to...units in offensive operations. A Shadow unmanned aerial system vehicle launches to conduct a surveillance mission, in Baghdad, Iraq. P ho to b y S S...interest produced similar lackluster results. On the rare occasions when the unmanned aerial system observed seem- ingly “suspicious” activity, the

  17. The Impact of Unmanned Aerial Systems on Joint Operational Art

    DTIC Science & Technology

    2012-05-17

    The Impact of Unmanned Aerial Systems on Joint Operational Art A Monograph by Major Joel E Pauls USAF School of Advanced Military Studies...Unmanned Aerial Systems on Joint Operational Art 6. AUTHOR(S) Joel E. Pauls Major, United States Air Force 7. PERFORMING ORGANIZATION NAME(S) AND...Approved for Public Release; Distribution is Unlimited 13. ABSTRACT (Maximum 200 Words) The use of Unmanned Aerial Systems (UAS) by the United States

  18. Quantification of 235U and 238U activity concentrations for undeclared nuclear materials by a digital gamma-gamma coincidence spectroscopy.

    PubMed

    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.

  19. Resonance production in. gamma gamma. collisions

    SciTech Connect

    Renard, F.M.

    1983-04-01

    The processes ..gamma gamma.. ..-->.. hadrons can be depicted as follows. One photon creates a q anti q pair which starts to evolve; the other photon can either (A) make its own q anti q pair and the (q anti q q anti q) system continue to evolve or (B) interact with the quarks of the first pair and lead to a modified (q anti q) system in interaction with C = +1 quantum numbers. A review of the recent theoretical activity concerning resonance production and related problems is given under the following headings: hadronic C = +1 spectroscopy (q anti q, qq anti q anti q, q anti q g, gg, ggg bound states and mixing effects); exclusive ..gamma gamma.. processes (generalities, unitarized Born method, VDM and QCD); total cross section (soft and hard contributions); q/sup 2/ dependence of soft processes (soft/hard separation, 1/sup +- +/ resonances); and polarization effects. (WHK)

  20. 1. Aerial view, looking northeast up Newark Bay, showing entire ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Aerial view, looking northeast up Newark Bay, showing entire island Charles Wisniewski, photographer, January 1985 - Shooters Island, Ships Graveyard, Newark Bay, Staten Island (subdivision), Richmond County, NY

  1. HISTORIC IMAGE: AERIAL VIEW WITH THE CEMETERY IN BACKGROUND. PHOTOGRAPH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    HISTORIC IMAGE: AERIAL VIEW WITH THE CEMETERY IN BACKGROUND. PHOTOGRAPH 29 OCTOBER 1959. NCA HISTORY COLLECTION. - Black Hills National Cemetery, 20901 Pleasant Valley Drive, Sturgis, Meade County, SD

  2. HISTORIC IMAGE: AERIAL VIEW WITH NEW EXPRESSWAY IN FOREGROUND. PHOTOGRAPH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    HISTORIC IMAGE: AERIAL VIEW WITH NEW EXPRESSWAY IN FOREGROUND. PHOTOGRAPH 19 SEPTEMBER 1978. NCA HISTORY COLLECTION. - Black Hills National Cemetery, 20901 Pleasant Valley Drive, Sturgis, Meade County, SD

  3. Application of airborne gamma spectrometric survey data to estimating terrestrial gamma-ray dose rates: an example in California.

    PubMed

    Wollenberg, H A; Revzan, K L; Smith, A R

    1994-01-01

    We examined the applicability of radioelement data from the National Aerial Radiometric Reconnaissance, an element of the National Uranium Resource Evaluation, to estimate terrestrial gamma-ray absorbed dose rates, by comparing dose rates calculated from aeroradiometric surveys of uranium, thorium, and potassium concentrations with dose rates calculated from a radiogeologic data base and the distribution of lithologies in California. Gamma-ray dose rates increase generally from north to south following lithological trends, with low values of 25-30 nGy h-1 in the northernmost 1 x 2 degrees quadrangles between 41 and 42 degrees N to high values of 75-100 nGy h-1 in southeastern California. Lithologic-based estimates of mean dose rates in the quadrangles generally match those from aeroradiometric data, with statewide means of 63 and 60 nGy h-1, respectively. These are intermediate between a population-weighted global average of 51 nGy h-1 reported in 1982 by UNSCEAR and a weighted continental average of 70 nGy h-1, based on the global distribution of rock types. The concurrence of lithologically and aeroradiometrically determined dose rates in California, with its varied geology and topography encompassing settings representative of the continents, indicates that the National Aerial Radiometric Reconnaissance data are applicable to estimates of terrestrial absorbed dose rates from natural gamma emitters.

  4. Formation of gamma(sup prime)-Ni3Al via the Peritectoid Reaction: gamma + beta (+ Al2O3)=gamma(sup prime)(+ Al2O3)

    NASA Technical Reports Server (NTRS)

    Copeland, Evan

    2008-01-01

    The activities of Al and Ni were measured using multi-cell Knudsen effusion-cell mass spectrometry (multi-cell KEMS), over the composition range 8-32 at.%Al and temperature range T=1400-1750 K in the Ni-Al-O system. These measurements establish that equilibrium solidification of gamma(sup prime)-Ni3Al-containing alloys occurs by the eutectic reaction, L (+ Al2O3)=gamma + Beta(+ Al2O3), at 1640 +/- 1 K and a liquid composition of 24.8 +/- 0.2 at.%al (at an unknown oxygen content). The {gamma + Beta (+Al2O3} phase field is stable over the temperature range 1633-1640 K, and gamma(sup prime)-Ni3Al forms via the peritectoid, gamma + Beta (+ Al2O3)=gamma(sup prime) (+ Al2O3), at 1633 +/- 1 K. This behavior is consistent with the current Ni-Al phase diagram and a new diagram is proposed. This new Ni-Al phase diagram explains a number of unusual steady-state solidification structures reported previously and provides a much simpler reaction scheme in the vicinity of the gamma(sup prime)-Ni2Al phase field.

  5. Formation of gamma'-Ni3Al via the Peritectoid Reaction: gamma plus beta (+Al2O3) equals gamma'(+Al2O3)

    NASA Technical Reports Server (NTRS)

    Copland, Evan

    2008-01-01

    The activities of Al and Ni were measured using multi-cell Knudsen effusion-cell mass spectrometry (multi-cell KEMS), over the composition range 8 - 32 at.%Al and temperature range T = 1400 - 1750 K in the Ni-Al-O system. These measurements establish that equilibrium solidification of gamma'-Ni3Al-containing alloys occurs by the eutectic reaction, L (+ Al2O3) = gamma + beta (+ Al2O3), at 1640 plus or minus 1 K and a liquid composition of 24.8 plus or minus 0.2 at.%Al (at an unknown oxygen content). The {gamma + beta + Al2O3} phase field is stable over the temperature range 1633 - 1640 K, and gamma'-Ni3Al forms via the peritectiod, gamma + beta (+ Al2O3) = gamma'(+ Al2O3), at 1633 plus or minus 1 K. This behavior is inconsistent with the current Ni-Al phase diagram and a new diagram is proposed. This new Ni-Al phase diagram explains a number of unusual steady state solidification structures reported previously and provides a much simpler reaction scheme in the vicinity of the gamma'-Ni3Al phase field.

  6. An aerial 3D printing test mission

    NASA Astrophysics Data System (ADS)

    Hirsch, Michael; McGuire, Thomas; Parsons, Michael; Leake, Skye; Straub, Jeremy

    2016-05-01

    This paper provides an overview of an aerial 3D printing technology, its development and its testing. This technology is potentially useful in its own right. In addition, this work advances the development of a related in-space 3D printing technology. A series of aerial 3D printing test missions, used to test the aerial printing technology, are discussed. Through completing these test missions, the design for an in-space 3D printer may be advanced. The current design for the in-space 3D printer involves focusing thermal energy to heat an extrusion head and allow for the extrusion of molten print material. Plastics can be used as well as composites including metal, allowing for the extrusion of conductive material. A variety of experiments will be used to test this initial 3D printer design. High altitude balloons will be used to test the effects of microgravity on 3D printing, as well as parabolic flight tests. Zero pressure balloons can be used to test the effect of long 3D printing missions subjected to low temperatures. Vacuum chambers will be used to test 3D printing in a vacuum environment. The results will be used to adapt a current prototype of an in-space 3D printer. Then, a small scale prototype can be sent into low-Earth orbit as a 3-U cube satellite. With the ability to 3D print in space demonstrated, future missions can launch production hardware through which the sustainability and durability of structures in space will be greatly improved.

  7. D Surface Generation from Aerial Thermal Imagery

    NASA Astrophysics Data System (ADS)

    Khodaei, B.; Samadzadegan, F.; Dadras Javan, F.; Hasani, H.

    2015-12-01

    Aerial thermal imagery has been recently applied to quantitative analysis of several scenes. For the mapping purpose based on aerial thermal imagery, high accuracy photogrammetric process is necessary. However, due to low geometric resolution and low contrast of thermal imaging sensors, there are some challenges in precise 3D measurement of objects. In this paper the potential of thermal video in 3D surface generation is evaluated. In the pre-processing step, thermal camera is geometrically calibrated using a calibration grid based on emissivity differences between the background and the targets. Then, Digital Surface Model (DSM) generation from thermal video imagery is performed in four steps. Initially, frames are extracted from video, then tie points are generated by Scale-Invariant Feature Transform (SIFT) algorithm. Bundle adjustment is then applied and the camera position and orientation parameters are determined. Finally, multi-resolution dense image matching algorithm is used to create 3D point cloud of the scene. Potential of the proposed method is evaluated based on thermal imaging cover an industrial area. The thermal camera has 640×480 Uncooled Focal Plane Array (UFPA) sensor, equipped with a 25 mm lens which mounted in the Unmanned Aerial Vehicle (UAV). The obtained results show the comparable accuracy of 3D model generated based on thermal images with respect to DSM generated from visible images, however thermal based DSM is somehow smoother with lower level of texture. Comparing the generated DSM with the 9 measured GCPs in the area shows the Root Mean Square Error (RMSE) value is smaller than 5 decimetres in both X and Y directions and 1.6 meters for the Z direction.

  8. Photogrammetric mapping using unmanned aerial vehicle

    NASA Astrophysics Data System (ADS)

    Graça, N.; Mitishita, E.; Gonçalves, J.

    2014-11-01

    Nowadays Unmanned Aerial Vehicle (UAV) technology has attracted attention for aerial photogrammetric mapping. The low cost and the feasibility to automatic flight along commanded waypoints can be considered as the main advantages of this technology in photogrammetric applications. Using GNSS/INS technologies the images are taken at the planned position of the exposure station and the exterior orientation parameters (position Xo, Yo, Zo and attitude ω, φ, χ) of images can be direct determined. However, common UAVs (off-the-shelf) do not replace the traditional aircraft platform. Overall, the main shortcomings are related to: difficulties to obtain the authorization to perform the flight in urban and rural areas, platform stability, safety flight, stability of the image block configuration, high number of the images and inaccuracies of the direct determination of the exterior orientation parameters of the images. In this paper are shown the obtained results from the project photogrammetric mapping using aerial images from the SIMEPAR UAV system. The PIPER J3 UAV Hydro aircraft was used. It has a micro pilot MP2128g. The system is fully integrated with 3-axis gyros/accelerometers, GPS, pressure altimeter, pressure airspeed sensors. A Sony Cyber-shot DSC-W300 was calibrated and used to get the image block. The flight height was close to 400 m, resulting GSD near to 0.10 m. The state of the art of the used technology, methodologies and the obtained results are shown and discussed. Finally advantages/shortcomings found in the study and main conclusions are presented

  9. BOREAS Level-0 C-130 Aerial Photography

    NASA Technical Reports Server (NTRS)

    Newcomer, Jeffrey A.; Dominguez, Roseanne; Hall, Forrest G. (Editor)

    2000-01-01

    For BOReal Ecosystem-Atmosphere Study (BOREAS), C-130 and other aerial photography was collected to provide finely detailed and spatially extensive documentation of the condition of the primary study sites. The NASA C-130 Earth Resources aircraft can accommodate two mapping cameras during flight, each of which can be fitted with 6- or 12-inch focal-length lenses and black-and-white, natural-color, or color-IR film, depending upon requirements. Both cameras were often in operation simultaneously, although sometimes only the lower resolution camera was deployed. When both cameras were in operation, the higher resolution camera was often used in a more limited fashion. The acquired photography covers the period of April to September 1994. The aerial photography was delivered as rolls of large format (9 x 9 inch) color transparency prints, with imagery from multiple missions (hundreds of prints) often contained within a single roll. A total of 1533 frames were collected from the C-130 platform for BOREAS in 1994. Note that the level-0 C-130 transparencies are not contained on the BOREAS CD-ROM set. An inventory file is supplied on the CD-ROM to inform users of all the data that were collected. Some photographic prints were made from the transparencies. In addition, BORIS staff digitized a subset of the tranparencies and stored the images in JPEG format. The CD-ROM set contains a small subset of the collected aerial photography that were the digitally scanned and stored as JPEG files for most tower and auxiliary sites in the NSA and SSA. See Section 15 for information about how to acquire additional imagery.

  10. Aerial thermography in archaeological prospection: Applications & processing

    NASA Astrophysics Data System (ADS)

    Cool, Autumn Chrysantha

    Aerial thermography is one of the least utilized archaeological prospection methods, yet it has great potential for detecting anthropogenic anomalies. Thermal infrared radiation is absorbed and reemitted at varying rates by all objects on and within the ground depending upon their density, composition, and moisture content. If an area containing archaeological features is recorded at the moment when their thermal signatures most strongly contrast with that of the surrounding matrix, they can be visually identified in thermal images. Research conducted in the 1960s and 1970s established a few basic rules for conducting thermal survey, but the expense associated with the method deterred most archaeologists from using this technology. Subsequent research was infrequent and almost exclusively appeared in the form of case studies. However, as the current proliferation of unmanned aerial vehicles (UAVs) and compact thermal cameras draws renewed attention to aerial thermography as an attractive and exciting form of survey, it is appropriate and necessary to reevaluate our approach. In this thesis I have taken a two-pronged approach. First, I built upon the groundwork of earlier researchers and created an experiment to explore the impact that different environmental and climatic conditions have on the success or failure of thermal imaging. I constructed a test site designed to mimic a range of archaeological features and imaged it under a variety of conditions to compare and contrast the results. Second, I explored a new method for processing thermal data that I hope will lead to a means of reducing noise and increasing the clarity of thermal images. This step was done as part of a case study so that the effectiveness of the processing method could be evaluated by comparison with the results of other geophysical surveys.

  11. Gamma titanium aluminide alloys

    SciTech Connect

    Yamaguchi, M.; Inui, H.; Kishida, K.; Matsumuro, M.; Shirai, Y.

    1995-08-01

    Extensive progress and improvements have been made in the science and technology of gamma titanium aluminide alloys within the last decade. In particular, the understanding of their microstructural characteristics and property/microstructure relationships has been substantially deepened. Based on these achievements, various engineering two-phase gamma alloys have been developed and their mechanical and chemical properties have been assessed. Aircraft and automotive industries arc pursuing their introduction for various structural components. At the same time, recent basic studies on the mechanical properties of two-phase gamma alloys, in particular with a controlled lamellar structure have provided a considerable amount of fundamental information on the deformation and fracture mechanisms of the two-phase gamma alloys. The results of such basic studies are incorporated in the recent alloy and microstructure design of two-phase gamma alloys. In this paper, such recent advances in the research and development of the two-phase gamma alloys and industrial involvement are summarized.

  12. Aerial view of the Press Site

    NASA Technical Reports Server (NTRS)

    1998-01-01

    In this aerial view, The News Center sits beyond a large parking lot, on a hill at the northeastern end of the Launch Complex 39 Area , next to the turn basin (at left). From left, the grandstand faces the launch pads several miles away on the Atlantic seashore; behind it, the television studio is the site of media conferences; next, the large white-roofed building is the hub of information and activity for press representatives. Lined up on the right of the Press Site are various buildings and trailers, home to major news networks. The parking lot can accommodate the hundreds of media personnel who attend Space Shuttle launches.

  13. Human Operator Modeling for Aerial Tracking.

    DTIC Science & Technology

    1980-12-01

    HUMAN OPERATOR MODELING FOR AERIAL TRACKING JONA THAN KORN ARTER. EPHRATH DA VLD L. KLEINMAN DBCXMBt 19MDTICSELECTE APR 3 1981.j B Approwd for pVA& u...8217the "Guid 8en th Cart end Use of laboratory Animals, "Inatitate of Laboratory Animl ReaNuWAes, National Rtesarch CouncL The voluntary Infomed consent...Continue. on reverse aide If necessary and identify hc block numbrh) ._Modern Optimal Control techniques are e:iployed to investigate and model human

  14. Adaptive control of an unmanned aerial vehicle

    NASA Astrophysics Data System (ADS)

    Nguen, V. F.; Putov, A. V.; Nguen, T. T.

    2017-01-01

    The paper deals with design and comparison of adaptive control systems based on plant state vector and output for unmanned aerial vehicle (UAV) with nonlinearity and uncertainty of parameters of the aircraft incomplete measurability of its state and presence of wind disturbances. The results of computer simulations of flight stabilization processes on the example of the experimental model UAV-70V (Aerospace Academy, Hanoi) with presence of periodic and non-periodic vertical wind disturbances with designed adaptive control systems based on plant state vector with state observer and plant output.

  15. Aerial views of the San Andreas Fault

    USGS Publications Warehouse

    Moore, M.

    1988-01-01

    These aerial photographs of the San Andreas fault were taken in 1965 by Robert E. Wallace of the U.S Geological Survey. The pictures were taken with a Rolliflex camera on 20 format black and white flim; Wallace was aboard a light, fixed-wing aircraft, flying mostly at low altitudes. He photographed the fault from San Francisco near its north end where it enters by the Salton Sea. These images represent only a sampling of the more than 300 images prodcued during this project. All the photographs reside in the U.S Geological Survey Library in Menlo Park, California. 

  16. Delivery of Unmanned Aerial Vehicle Data

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.; Sullivan, Donald V.

    2011-01-01

    To support much of NASA's Upper Atmosphere Research Program science, NASA has acquired two Global Hawk Unmanned Aerial Vehicles (UAVs). Two major missions are currently planned using the Global Hawk: the Global Hawk Pacific (GloPac) and the Genesis and Rapid Intensification Processes (GRIP) missions. This paper briefly describes GloPac and GRIP, the concept of operations and the resulting requirements and communication architectures. Also discussed are requirements for future missions that may use satellite systems and networks owned and operated by third parties.

  17. Aerial view of Runway 33 at SLF

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This aerial view shows the approach on Runway 33 at the KSC Shuttle Landing Facility. The runway is 15,000 feet long, with 1,000-foot paved overruns at each end; 300 feet wide (about length of football field), with 50-foot asphalt shoulders each side; 16 inches thick in the center, and 15 inches thick on sides. It has a slope of 24 inches from the center line to the edge for drainage. The single landing strip is considered two runways, depending on approach -- Runway 15 from northwest, Runway 33 from southeast.

  18. Aerial view of Runway 33 at SLF

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This aerial view shows the approach on Runway 33 at the KSC Shuttle Landing Facility. The runway is 15,000 feet long, with 1,000-foot paved overruns at each end; 300 feet wide (about length of football field), with 50-foot asphalt shoulders each side; 16 inches thick in the center, and 15 inches thick on sides. It has a slope of 24 inches from the center line to the edge for drainage. The single landing strip is considered two runways, depending on approach -- Runway 15 from northwest, Runway 33 from southeast.

  19. Aeolic vibration of aerial electricity transmission cables

    NASA Astrophysics Data System (ADS)

    Avila, A.; Rodriguez-Vera, Ramon; Rayas, Juan A.; Barrientos, Bernardino

    2005-02-01

    A feasibility study for amplitude and frequency vibration measurement in aerial electricity transmission cable has been made. This study was carried out incorporating a fringe projection method for the experimental part and horizontal taut string model for theoretical one. However, this kind of model ignores some inherent properties such as cable sag and cable inclination. Then, this work reports advances on aeolic vibration considering real cables. Catenary and sag are considered in our theoretical model in such a way that an optical theodolite for measuring has been used. Preliminary measurements of the catenary as well as numerical simulation of a sagged cable vibration are given.

  20. Indirect Signatures of CP Violation in the Processes {gamma}{gamma} {yields} {gamma}{gamma}, {gamma}Z, and ZZ

    SciTech Connect

    Petriello, Frank J

    2001-07-25

    This paper studies the utility of the processes {gamma}{gamma} {yields} {gamma}{gamma}, {gamma}Z, and ZZ in searching for sources of CP violation arising from energy scales beyond the production thresholds of planned future colliders. In the context of an effective Lagrangian approach we consider the most general set of CP odd SU(2) x U(1) operators that give rise to genuinely quartic gauge boson couplings which can be probed in 2 {yields} 2 scattering processes at a {gamma}{gamma} collider. We study each process in detail, emphasizing the complementary information that is obtained by varying the initial beam polarizations. Finally, we compare our results to other constraints in the literature on CP odd gauge boson interactions and quartic gauge boson couplings; the search reaches obtained here are typically stronger and nicely complement previous studies which have focused primarily on W boson, top quark, or Higgs production.