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

International Nuclear Information System (INIS)

Al-Azmi, Darwish; Karunakara, N.

2007-01-01

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

Measurements of Soil Carbon by Neutron-Gamma Analysis in Static and Scanning Modes.

Science.gov (United States)

Yakubova, Galina; Kavetskiy, Aleksandr; Prior, Stephen A; Torbert, H Allen

2017-08-24

The herein described application of the inelastic neutron scattering (INS) method for soil carbon analysis is based on the registration and analysis of gamma rays created when neutrons interact with soil elements. The main parts of the INS system are a pulsed neutron generator, NaI(Tl) gamma detectors, split electronics to separate gamma spectra due to INS and thermo-neutron capture (TNC) processes, and software for gamma spectra acquisition and data processing. This method has several advantages over other methods in that it is a non-destructive in situ method that measures the average carbon content in large soil volumes, is negligibly impacted by local sharp changes in soil carbon, and can be used in stationary or scanning modes. The result of the INS method is the carbon content from a site with a footprint of ~2.5 - 3 m 2 in the stationary regime, or the average carbon content of the traversed area in the scanning regime. The measurement range of the current INS system is >1.5 carbon weight % (standard deviation ± 0.3 w%) in the upper 10 cm soil layer for a 1 hmeasurement.

Measurement of structured purple soil porosity by using gamma ray transmission technique

International Nuclear Information System (INIS)

Costa, Elizabeth Cristina S. da; Rocha, Wilson Roberto Dejato da; Oliveira, Ricardo M. de; Silva, Luzeli Moreira da; Moreira, Anderson Camargo; Portezan, Otaio Portezan; Appoloni, Carlos Roberto; Coimbra, Melayne Martins

2002-01-01

The soil structure defines the particle arrangement which in turn largely determines the pore size distribution. In this work, we present the measurements of total, macro and microporosity for TRe soil with clayey texture. Soil samples were collected from a trench located at University of Londrina. The deformed and undeformed soil samples were collected from soil surface down to the depth of 0,50 m in 0,10 m intervals and separated into six aggregate size classes: 0.053; 0.125; 0.30; 0.71; 2 e 4 mm. We also prepared samples mixing different size classes, like as: (4+0.125), (2+0.125), (4+2+0.71), (4+2+0.30) e (4+0.30+0.125)mm. Measurements of particle density and aggregate bulk density using conventional method were performed to all depths. The linear soil attenuation coefficients and aggregate soil attenuation coefficients were measured with gamma-ray transmission system using an 241 Am (59,53 keV and 100 mCi) radiation source, a (2 x 2) in NaI scintillation detector, cylindric collimators (2 mm diameter to the source and 5 mm diameter to the detector) and gamma spectrometry standard electronics, connected to a multichannel. The obtained results for total, macro and microporosity are in a good agreement with the ones using the convention method, showing the applicability of the gamma-ray transmission method. (author)

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

CERN Document Server

American Society for Testing and Materials. Philadelphia

2004-01-01

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

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

International Nuclear Information System (INIS)

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

1976-01-01

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

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

International Nuclear Information System (INIS)

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

1977-01-01

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

Soil sample moisture content as a function of time during oven drying for gamma-ray spectroscopic measurements

International Nuclear Information System (INIS)

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

1999-01-01

In routine gamma-ray spectroscopic analysis of collected soil samples, procedure often calls to remove soil moisture by oven drying overnight at a temperature of 100 deg. C . Oven drying not only minimizes the gamma-ray self-attenuation of soil samples due to the absence of water during the gamma-ray spectroscopic analysis, but also allows for a straightforward calculation of the specific activity of radionuclides in soil, historically based on the sample dry weight. Because radon exhalation is strongly dependent on moisture , knowledge of the oven-drying time dependence of the soil moisture content, combined with radon exhalation measurements during oven drying and at room temperature for varying soil moisture contents, would allow conclusions to be made on how the oven-drying radon exhalation rate depends on soil moisture content. Determinations of the oven-drying radon exhalation from soil samples allow corrections to be made for the immediate laboratory gamma-ray spectroscopy of radionuclides in the natural uranium decay chain. This paper presents the results of soil moisture content measurements during oven drying and suggests useful empirical fits to the moisture data

Prediction of terrestrial gamma dose rate based on geological formations and soil types in the Johor State, Malaysia

International Nuclear Information System (INIS)

Saleh, Muneer Aziz; Ramli, Ahmad Termizi; Hamzah, Khaidzir bin; Alajerami, Yasser; Moharib, Mohammed; Saeed, Ismael

2015-01-01

This study aims to predict and estimate unmeasured terrestrial gamma dose rate (TGDR) using statistical analysis methods to derive a model from the actual measurement based on geological formation and soil type. The measurements of TGDR were conducted in the state of Johor with a total of 3873 measured points which covered all geological formations, soil types and districts. The measurements were taken 1 m above the soil surface using NaI [Ti] detector. The measured gamma dose rates ranged from 9 nGy h −1 to 1237 nGy h −1 with a mean value of 151 nGy h −1 . The data have been normalized to fit a normal distribution. Tests of significance were conducted among all geological formations and soil types, using the unbalanced one way ANOVA. The results indicated strong significant differences due to the different geological formations and soil types present in Johor State. Pearson Correlation was used to measure the relations between gamma dose rate based on geological formation and soil type (D G,S ) with the gamma dose rate based on geological formation (D G ) or soil type (D s ). A very good correlation was found between D G,S and D G or D G,S and D s . A total of 118 pairs of geological formations and soil types were used to derive the statistical contribution of geological formations and soil types to gamma dose rates. The contribution of the gamma dose rate from geological formation and soil type were found to be 0.594 and 0.399, respectively. The null hypotheses were accepted for 83% of examined data, therefore, the model could be used to predict gamma dose rates based on geological formation and soil type information. - Highlights: • A very good correlation coefficient was found between D G,S and D G or D G,S and D s . • The contribution of the gamma dose rate from geological formation (GDR) is 0.594. • The contribution of the GDR from soil type was found to be 0.399. • A 83% of examined data were accepted the null hypotheses. • The model

Gamma-emissions of some meteorites and terrestrial rocks. Evaluation of lunar soil radioactivity

International Nuclear Information System (INIS)

Nordemann, D.

1966-01-01

The gamma-emissions of some terrestrial rocks and of the following meteorites: Bogou, Eagle-Station, Granes, and Dosso were studied by quantitative low background gamma spectrometry. These measurements and their interpretation lead to the evaluation of the possible gamma-emissions of several models of lunar soils. (author) [fr

Study of time variation of terrestrial gamma radiation due to depth distribution of soil moisture content

International Nuclear Information System (INIS)

Yoshioka, Katsuhiro

1994-01-01

An empirical equation was deduced from studies of time variations of terrestrial gamma exposure rate and soil moisture content with depth distribution in the surface layer. It was definitely suggested that the variation of terrestrial gamma exposure rate is most strongly influenced by the change of soil moisture content at 5 cm depth. The seasonal variation with a relative maximum in early autumn and a relative minimum in early spring was clearly obtained in the consequence of long time measurements of terrestrial gamma exposure rate and degree of soil dryness. The diurnal change and phase difference due to the effect of depth were also obtained in the dynamic characteristics of soil moisture content at 3 different depths. From the comparison between measured terrestrial gamma exposure rate and that evaluated from soil moisture content using the empirical equation, it was seen that seasonal variations of the both agreed fairly well as a whole. (author)

Prediction of terrestrial gamma dose rate based on geological formations and soil types in the Johor State, Malaysia.

Science.gov (United States)

Saleh, Muneer Aziz; Ramli, Ahmad Termizi; bin Hamzah, Khaidzir; Alajerami, Yasser; Moharib, Mohammed; Saeed, Ismael

2015-10-01

This study aims to predict and estimate unmeasured terrestrial gamma dose rate (TGDR) using statistical analysis methods to derive a model from the actual measurement based on geological formation and soil type. The measurements of TGDR were conducted in the state of Johor with a total of 3873 measured points which covered all geological formations, soil types and districts. The measurements were taken 1 m above the soil surface using NaI [Ti] detector. The measured gamma dose rates ranged from 9 nGy h(-1) to 1237 nGy h(-1) with a mean value of 151 nGy h(-1). The data have been normalized to fit a normal distribution. Tests of significance were conducted among all geological formations and soil types, using the unbalanced one way ANOVA. The results indicated strong significant differences due to the different geological formations and soil types present in Johor State. Pearson Correlation was used to measure the relations between gamma dose rate based on geological formation and soil type (D(G,S)) with the gamma dose rate based on geological formation (D(G)) or soil type (D(s)). A very good correlation was found between D(G,S) and D(G) or D(G,S) and D(s). A total of 118 pairs of geological formations and soil types were used to derive the statistical contribution of geological formations and soil types to gamma dose rates. The contribution of the gamma dose rate from geological formation and soil type were found to be 0.594 and 0.399, respectively. The null hypotheses were accepted for 83% of examined data, therefore, the model could be used to predict gamma dose rates based on geological formation and soil type information. Copyright © 2015 Elsevier Ltd. All rights reserved.

Feasibility study of photodiodes utilization in the soil-moisture determination by gamma transmission

International Nuclear Information System (INIS)

Santos, L.A.P. dos.

1992-08-01

This study was done to verify the viability of photodiodes, as gamma radiation detector ( 241 Am - Energy=60 KeV), to measure soil water content. The photodiodes used had different mechanical and electrical characteristics, and were tested on soils of different textures. A good linear correlation between the logarithm of the attenuation factor and soil-moisture demonstrated such viability, and that the low photopeak efficiency of these devices is not a limitation to the measurement of soil water content. Furthermore, the stability, the portability, and low cost of such semiconductor devices, including its electronic system, represent relevant characteristics that may justify the development of a reliable gamma meter system for field studies. (author). 37 refs, 21 figs, 20 tabs

Evaluation of gamma activities of naturally occurring radioactive materials in uncontaminated surface soils of Jamaica

International Nuclear Information System (INIS)

Maurice Miller; Mitko Voutchkov

2014-01-01

In this study a geological, lithological or pedogenesis analysis is used to explain the values and distribution of the primordial specific gamma activities in the Jamaican soil environment. A random systematic sampling method resulted in Jamaica being divided into 50 square grids with a maximum sampling density of 225 square meters per sample. The resulting sixty-eight (68) samples were measured on a Canberra HPGe detector for 24 h and the photopeaks for the primordial gammas of 238 U, 232 Th and 40 K analyzed. Spearman's correlation was used to investigate the relationships between the primordial specific activities and the geological features of the soil samples collected and the geographic information system, ArcGIS v10.1 used to graphically depict the gamma profile of the primordials across the island. The Kruskal-Wallis test indicated that in general the variations of the primordial gamma specific activities over the underlying soil geologies were statistically significant. However, the pairwise Post-Hoc test results did not suggest a significant variation in mean specific for any of the primordial with all the underlying geology even when the unadjusted p value was used. This result along with the Spearman's coefficient correlation values suggested a moderate to weak relationship between the gamma profile of the top soil and its underlying geology. With the exception of a weak correlation with 232 Th (-0.295) no other primordial radionuclide correlated with the UNESCO/FAO soil categories for the island. The most significant correlations for soil characteristics and gamma activities were organic matters which were positive for 232 Th (0.518), 238 U (0.481) but negative for 40 K (-0.284). (author)

Measurement of the vertical infiltration parameters and water redistribution in LRd and LEa soils by gamma-ray transmission technique

International Nuclear Information System (INIS)

Souza, A.D.B. de; Saito, H.; Appoloni, C.R.; Coimbra, M.M.; Parreira, P.S.

1991-01-01

The properties of soil water diffusivity and soil hydraulic conductivity of two horizons (0-20 cm and 20-40 cm) from Latossolo Roxo distrofico (LRd) and Latossolo Vermelho escuro (LEa) soil samples, have been measured in laboratory through the vertical infiltration and redistribution of water in soil columns. The moisture profile as a function of time for each position in the soil column were obtained with the gamma-ray transmission technique, using a sup(241)Am gamma-ray source, a Na (I) T1 scintillation detector and gamma spectrometry standard electronic. (author)

Monitoring of Natural Soil Radioactivity with Portable Gamma-Ray Spectrometers

DEFF Research Database (Denmark)

Bøtter-Jensen, Lars; Løvborg, Leif; Kirkegaard, Peter

1979-01-01

Two portable NaI(Tl) spectrometers with four energy windows were used for the recording of gamma-ray counts over soil and rock of differing natural radioactivity. The exposure rates at the field sites were simultaneously measured with a high-pressure argon ionization chamber. Background measureme......Two portable NaI(Tl) spectrometers with four energy windows were used for the recording of gamma-ray counts over soil and rock of differing natural radioactivity. The exposure rates at the field sites were simultaneously measured with a high-pressure argon ionization chamber. Background...... measurements at sea were carried out in order to estimate the non-terrestrial contributions to the instrument readings. Counts recorded in the three high-energy windows of the spectrometers were converted into radiometrically equivalent concentrations of thorium, uranium, and potassium in the ground. Large....... The theoretical exposure rates deducible from the experimental radioelement concentrations at the field sites were in good agreement both with the ionization-chamber readings (corrected for cosmic-ray background) and with the exposure rates measured by total gamma-ray counting. From this and other results...

Application of airborne gamma-ray spectrometry in soil/regolith mapping and applied geomorphology

International Nuclear Information System (INIS)

Wilford, J.R.; Bierwirth, P.N.; Craig, M.A.

1997-01-01

Gamma-ray spectrometric surveys are an important source of information for soil, regolith and geomorphological studies, as demonstrated by the interpretation of airborne surveys in Western Australia, central New South Wales and north Queensland. Gamma-rays emitted from the ground surface relate to the primary mineralogy and geochemistry of the bedrock, and the secondary weathered materials. Weathering modifies the distribution and concentration of radioelements from the original bedrock source. Once the radioelement response of bedrock and weathered materials is understood, the gamma-ray data can provide information on geomorphic processes and soil/regolith properties, including their mineralogy, texture, chemistry and style of weathering. This information can contribute significantly to an understanding of the weathering and geomorphic history of a region and, therefore, has the potential to be used in developing more effective land-management strategies and refining geochemical models in support of mineral exploration. Gamma-ray imagery is enhanced when combined with Landsat TM bands and digital elevation models (DEM). This synergy enables geochemical information derived from the gamma-ray data to be interpreted within a geomorphic framework. Draping gamma-ray images over DEMs as 3D landscape perspective views aids interpretation and allows the interpreter to visualise complex relationships between the gamma-ray response and landform features. 44 refs.,1 tab., 11 figs

Proximal gamma-ray spectroscopy to predict soil properties using windows and full-spectrum analysis methods.

Science.gov (United States)

Mahmood, Hafiz Sultan; Hoogmoed, Willem B; van Henten, Eldert J

2013-11-27

Fine-scale spatial information on soil properties is needed to successfully implement precision agriculture. Proximal gamma-ray spectroscopy has recently emerged as a promising tool to collect fine-scale soil information. The objective of this study was to evaluate a proximal gamma-ray spectrometer to predict several soil properties using energy-windows and full-spectrum analysis methods in two differently managed sandy loam fields: conventional and organic. In the conventional field, both methods predicted clay, pH and total nitrogen with a good accuracy (R2 ≥ 0.56) in the top 0-15 cm soil depth, whereas in the organic field, only clay content was predicted with such accuracy. The highest prediction accuracy was found for total nitrogen (R2 = 0.75) in the conventional field in the energy-windows method. Predictions were better in the top 0-15 cm soil depths than in the 15-30 cm soil depths for individual and combined fields. This implies that gamma-ray spectroscopy can generally benefit soil characterisation for annual crops where the condition of the seedbed is important. Small differences in soil structure (conventional vs. organic) cannot be determined. As for the methodology, we conclude that the energy-windows method can establish relations between radionuclide data and soil properties as accurate as the full-spectrum analysis method.

Dried gamma-irradiated sewage solids use on calcareous soils: crop yields and heavy metals uptake

International Nuclear Information System (INIS)

McCaslin, B.D.; Sivinski, J.S.

1980-01-01

The fertilizer values of gamma-irradiated digested sewage solids (RDSS) and gamma-irradiated undigested sewage solids (RUSS) have been examined on calcareous soils. Previously published data from Sandia Laboratories have shown that approximately 1 mega-rad of gamma-irradiation effectively destroys pathogenic bacteria, parasites and plant seeds in dried sewage solids. Greenhouse experiments directly comparing gamma-irradiated and non-irradiated undigested and digested dried sewage solids as fertilizers indicate little or no effect of 1 mega-rad gamma radiation treatment on plant yield or plant-nutrient uptake and demonstrated considerable benefit from using sewage solids on calcareous soils. Plant response to undigested sewage solids was considerably greater than to digested sewage solids when applied at levels that were isonitrogenous. The calcareous soils in New Mexico typically range in pH from 7.5 to 9.0, limiting the plant-availability of many elements, especially heavy metals. Soils irrigated with sewage-effluent for 40 years demonstrated beneficial use of supplied plant-nutrients with no apparent increase in plant-uptake of heavy metals. RDSS applied to a calcareous soil low in plant-available iron increased plant growth in the greenhouse considerably more than treatments with equal amounts of nitrogen, phosphorus and iron applied as common fertilizer materials. Plant tissue concentrations of Fe, Zn, Mn and Cu showed that RDSS was a good source of these nutrients. Results also indicated that the total soluble salt concentration of the RDSS was the factor most limiting plant growth. Chromium, Cd, Ni and Pd plant-tissue concentrations were apparently not increased by RDSS treatments. (Auth.)

Remote sensing of acid sulfate soils using multispectral and gamma-ray data

International Nuclear Information System (INIS)

Bierwirth, P.N.; Graham, T.L.

1998-01-01

Acid sulfate soils are a significant environmental problem in coastal regions of Australia. Drainage and disturbance of coastal lands can result in acid soil degradation and the release of sulfuric acid and toxic metals into coastal waters. Remote sensing can provide a useful tool for detection of these soils and monitoring of their disturbance. As acid sulfate soils become oxidised with exposure to air, iron-minerals are produced and precipitate at the surface. This results from the breakdown of pyrite to form hydrated iron minerals and elemental sulfur, the oxidation of which produces acidity. The concentration of iron minerals at the surface can be an indicator of the level of acid sulfate soil activity in the near subsurface. These iron minerals include goethite, ferrihydrite and jarosite. Space-borne remote sensing scanners such as Landsat TM are capable of detecting iron minerals as a result of ferric ion absorption of solar radiation. Hyperspectral scanners are capable of further discrimination of individual minerals. This paper will discuss spectral characteristics of active acid sulfate soils and demonstrate the use of spectral unmixing algorithms on Landsat TM to detect problem areas at the surface. This method matches multispectral data to material reflectance-spectra known as end-members. These end-members or materials are then resolved mathematically as to their respective contributions to the overall reflectance (Bierwirth, 1990). In this way, abundances for particular materials can be derived.Digital elevation data was used to distinguish between the iron minerals due to weathering of bedrock in upland areas and acid sulfate soils on the plains. Also, the results of a high resolution (200m linespacing) airborne gamma-ray survey are presented. This data senses the concentration of radioelements down to about 40 cm depth and is largely unaffected by vegetation. Concentrations of gamma-emitting elements can indicate the type and depth of alluvium that

Gamma-ray beam attenuation to assess the influence of soil texture on structure deformation

International Nuclear Information System (INIS)

Pires, L.F.; Bacchi, O.O.S.; Dias, N.M.P.

2006-01-01

Gamma-ray beam attenuation is a non-invasive technique that permits analysis of soil porosity without disturbing the region of interest of the core sample. The technique has as additional advantage to allow measurements point by point on a millimetric scale in contrast to other methodologies that are invasive and analyze the soil properties in the bulk sample volume. Soil porosity can be used as an important parameter to quantify soil structural damages, which affect soil aeration, water movement and retention. In this study, porosities of three soils different in texture were measured at various positions in order to analyze the impact of the sampling procedure on the structure of each particular soil texture. The gamma-ray attenuation system consisted of an 241 Am radioactive source having an activity of 3.7 GBq, collimated with cylindrical lead collimators of 2 mm diameter. The results obtained show the presence of dense regions near the edges of samples and that different soil textures can suffer distinct deformations at sampling. (author)

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

International Nuclear Information System (INIS)

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

2015-01-01

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

Effect of Azospirillum brasilense inoculation on urease activity in soil and gamma-sterilized soil

International Nuclear Information System (INIS)

Perotti, E.B.R.; Pidello, A.

1999-01-01

Azospirillum spp. is considered a PGPR (plant growth promoting rhyzobacteria) bacterium, besides this interest, there is little information about its effects on other functional microbial groups or on soil enzymes. In this paper, the impact that Azospirillum brasilense 7001 inoculation has on urease activity expression in a Typic Argiudoll was studied. Evolution of urease activity of soil and of gamma irradiation (25 KGy) sterilized soil, and the inoculated strain survival were tested. The relation between soil urease activity and soil NH 4 +-N was also determined. In γ-sterilized soil, urease activity of inoculated soil increased with time, showing significant differences with regard to the control soil without inoculum at day 15. In non-sterile soil, urease activity decreased during the studied period in all treatments; in inoculated soil, it showed higher or lower values than the control depending on sampling time. Azospirillum survival was important and different according to soil condition conditions. The negative relation between NH 4 +-N concentration and soil urease activity (r 2 = 0.62) was observed in inoculated soil. The role of the addition of autoclaved inoculum in the urease activity expression is discussed. The research proves that in both studied situations Azospirillum modified soil urease activity, and that the competition with native microorganisms and soil NH 4 +-N may affect this bacterium capacity. (author)

Determination of the hydraulic conductivity in column of undeformed soil by gamma rays transmission

International Nuclear Information System (INIS)

Moreira, Anderson C.; Cavalcante, Fabio H.M.; Portezan Filho, Otavio; Coimbra, Melayne M.; Appoloni, Carlos Roberto

2000-01-01

The water infiltration process in undeformed soil column and the measurement of redistribution process by gamma rays transmission in different depth allow the determination of Hydraulic Conductivity K(Θ) function, using the Sisson et al. (1980) method. A LRd (dystrophic dark red soil) soil column with 60 cm of height, 10 cm of width and 5 cm of thickness, was analyzed in laboratory, reproducing the field conditions concerning to the water infiltration and redistribution in the soil. The soil moisture content data was obtained with a radioactivity source 241 Am (100 mCi; 59,6 keV), NaI (Tl) 2x2 detector, coupled to an gamma rays spectrometric electronic chain and a measurement table that allowed the vertical displacement of the soil column. The results indicate a growing behavior for K(Θ) in relation to the depth. The collimators had 2 mm and 5 mm diameter for radioactivity source and detector respectively. (author)

Effluent and gamma-irradiated digested sludge additions on calcareous soils

International Nuclear Information System (INIS)

Lee-Rodriguez, V.

1978-01-01

The long-term use of sewage effluent and the use of gamma-irradiated treated digested sewage sludge (RDSS) were studied under field and greenhouse conditions, respectively. The purpose of this investigation was to: (1) study the effect of long and short-term application of secondary sewage effluent and RDSS, respectively, on the buildup of iron and phytotoxicity problems on calcareous soils; (2) study the potential phytotoxicity of RDSS and observe the micronutrient fertilizer value of RDSS through three successive plantings on calcareous soil; (3) evaluate RDSS as a source of iron in a soil known to be severely iron-deficient

Simultaneous measurement of unfrozen water content and ice content in frozen soil using gamma ray attenuation and TDR

Science.gov (United States)

Zhou, Xiaohai; Zhou, Jian; Kinzelbach, Wolfgang; Stauffer, Fritz

2014-12-01

The freezing temperature of water in soil is not constant but varies over a range determined by soil texture. Consequently, the amounts of unfrozen water and ice change with temperature in frozen soil, which in turn affects hydraulic, thermal, and mechanical properties of frozen soil. In this paper, an Am-241 gamma ray source and time-domain reflectometry (TDR) were combined to measure unfrozen water content and ice content in frozen soil simultaneously. The gamma ray attenuation was used to determine total water content. The TDR was used to determine the dielectric constant of the frozen soil. Based on a four-phase mixing model, the amount of unfrozen water content in the frozen soil could be determined. The ice content was inferred by the difference between total water content and unfrozen water content. The gamma ray attenuation and the TDR were both calibrated by a gravimetric method. Water contents measured by gamma ray attenuation and TDR in an unfrozen silt column under infiltration were compared and showed that the two methods have the same accuracy and response to changes of water content. Unidirectional column freezing experiments were performed to apply the combined method of gamma ray attenuation and TDR for measuring unfrozen water content and ice content. The measurement error of the gamma ray attenuation and TDR was around 0.02 and 0.01 m3/m3, respectively. The overestimation of unfrozen water in frozen soil by TDR alone was quantified and found to depend on the amount of ice content. The higher the ice content, the larger the overestimation. The study confirmed that the combined method could accurately determine unfrozen water content and ice content in frozen soil. The results of soil column freezing experiments indicate that total water content distribution is affected by available pore space and the freezing front advance rate. It was found that there is similarity between the soil water characteristic and the soil freezing characteristic of

Correlation between gamma radiation levels and soil radium concentrations at the Edgemont uranium mill site

International Nuclear Information System (INIS)

Wallace, R.G.; Reed, R.P.; Polehn, J.L.; Wilson, G.T.

1985-01-01

The Tennessee Valley Authority's uranium mill in Edgemont, South Dakota, is being decommissioned. Approximately 4 million tons of contaminated tailings, building equipment, and contaminated soil and debris on the mill site will be removed to the disposal site located approximately 3 kilometers to the southeast. To minimize recontamination of cleaned areas, tailings removal will progress from the northwest corner to the southeast corner of the mill site. As specific areas are cleaned, surveys will be conducted to determine if the concentrations of radium-226 in soil are within the limits outlined in 40 CFR, Part 192. Conformance with the criteria will be demonstrated by a gamma survey of the area employing the differential, or delta-measurement, technique. This technique involves fitting the detector with a base and a receptacle for a removable high-density filter. By making measurements with and without the filter in place, a gamma radiation level proportional to the radium-226 concentration in soil can be determined. This paper describes the results obtained in the development of the correlation between the gamma survey measurements and the soil radium concentrations

Correlation between gamma radiation levels and soil radium concentrations at the Edgemont uranium mill site

International Nuclear Information System (INIS)

Wallace, R.G.; Reed, R.P.; Polehn, J.L.; Wilson, G.T.

1986-01-01

The Tennessee Valley Authority's uranium mill in Edgemont, South Dakota is being decommissioned. Approximately 4 million tons of contaminated tailings, building equipment, and contaminated soil and debris on the mill site will be removed to the disposal site located approximately 3 kilometers to the southeast. To minimize recontamination of cleaned areas, tailings removal will progress from the northwest corner to the southeast corner of the mill site. As specific areas are cleaned, surveys will be conducted to determine if the concentrations of radium-226 in soil are within the limits outlined in 40 CFR, Part 192. Conformance with the criteria will be demonstrated by a gamma survey of the area employing the differential, or delta-measurement, technique. This technique involves fitting the detector with a base and a receptacle for a removable high-density filter. By making measurements with and without the filter in place, a gamma radiation level proportional to the radium-226 concentration in soil can be determined. This paper describes the results obtained in the development of the correlation between the gamma survey measurements and the soil radium concentrations

A gamma-source method of measuring soil moisture

International Nuclear Information System (INIS)

Al-Jeboori, M.A.; Ameen, I.A.

1986-01-01

Water content in soil column was measured using NaI scintillation detector 5 mci Cs-137 as a gamma source. The measurements were done with a back scatter gauge, restricted with scattering angle less to than /2 overcome the effect of soil type. A 3 cm air gap was maintained between the front of the detector and the wall of the soil container in order to increase the counting rate. The distance between the center of the source and the center of the back scattering detector was 14 cm. The accuracy of the measurements was 0.63. For comparision, a direct rays method was used to measure the soil moisture. The results gave an error of 0.65. Results of the two methods were compared with the gravimetric method which gave an error of 0.18 g/g and 0.17 g/g for direct and back method respectively. The quick direct method was used to determine the gravimetric and volumetric percentage constants, and were found to be 1.62 and 0.865 respectively. The method then used to measure the water content in the layers of soil column.(6 tabs., 4 figs., 12 refs.)

Determination of soil parameters during the water horizontal infiltration and redistribution by gamma ray attenuation method and tensiometry

International Nuclear Information System (INIS)

Oliveira, J.C.M. de.

1991-04-01

The present work studies the water diffusivity and hydraulic conductivity in a Latossolo Roxo distrofico soil, during the water infiltration and redistribution processes. Variation water flow equations were utilized for the calculations. The data of wetting front positions and of soil water content profiles were obtained through the gamma ray attenuation from a 241-Am source, with 100 mCi activity detected by a standard electronic equipment of gamma spectrometry, with NaI CTD scintillation detector. From the soil water content data in function of space and time and from analytic models, the properties of soil water diffusivity and soil hydraulic conductivity were determined in the laboratory for the 0-10 cm and 10-25 soil layers. (author)

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

International Nuclear Information System (INIS)

Dragovic, Snezana; Onjia, Antonije

2006-01-01

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

Characterization of the gamma radioactive content in soils of the south cost of Guatemala

International Nuclear Information System (INIS)

Perez, Hector

2001-01-01

In this thesis results of measurements of 137C s in soils of the south cost of Guatemala are presented. The technique used is gamma spectroscopy using Ge(Hi) detector. The results shows that cesium is the main radionuclide present in the cultivated soils of Guatemala

Gamma Radiation Dose from Radionuclides in Soil Samples of Udagamandalam (Ooty) in India

International Nuclear Information System (INIS)

Selvasekarapandian, S.; Muguntha Manikandan, N.; Sivakumar, R.; Balasubramanian, S.; Venkatesan, T.; Meenakshisundram, V.; Ragunath, V.M.; Gajendran, V.

1999-01-01

The systematic study of background radiation and the distribution of radionuclides in the environment of Udagamandalam in Nilgiri District of Tamil Nadu has been made. Gamma spectrometric analysis of the soil samples of this area has been carried out. The measured gamma dose in air is in the range 31.6 nGy.h -1 - 221.1 nGy.h -1 with a mean value 121.8 nGy.h -1 . The average activities of the 232 Th series, 238 U series and 40 K in soil samples are 114.6 ± 52.5 Bq.kg -1 , 43.2 ± 23.2 Bq.kg -1 and 274.6 ± 86.7 Bq.kg -1 respectively. (author)

Gamma-spectrometric measurement of radioactivity in agricultural soils of the Lombardia region, northern Italy.

Science.gov (United States)

Guidotti, Laura; Carini, Franca; Rossi, Riccardo; Gatti, Marina; Cenci, Roberto M; Beone, Gian Maria

2015-04-01

This work is part of a wider monitoring project of the agricultural soils in Lombardia, which aims to build a database of topsoil properties and the potentially toxic elements, organic pollutants and gamma emitting radionuclides that the topsoils contain. A total of 156 agricultural soils were sampled according to the LUCAS (Land Use/Cover Area frame statistical Survey) standard procedure. The aim was to provide a baseline to document the conditions present at the time of sampling. The results of the project concerning soil radioactivity are presented here. The aim was to assess the content of (238)U, (232)Th, (137)Cs and (40)K by measuring soil samples by gamma spectrometry. (238)U, (232)Th and (40)K activities range 24-231, 20-70, and 242-1434 Bq kg(-1) respectively. The geographic distribution of (238)U reflects the geophysical framework of the Lombardia region: the soils with high content of uranium are distributed for the most part in the South Alpine belt, where the presence of magmatic rocks is widespread. These soils show an higher activity of (238)U than of (232)Th. The (238)U activities become lower than (232)Th when soils are located in the plain, originating from basic sedimentary rocks. (137)Cs activity ranges 0.4-86.8 kBq m(-2). The lowest activity of (137)Cs is in the plain, whereas the highest is in the North on soils kept as lawn or pasture. The (137)Cs activity of some samples suggests the presence of accumulation processes that lead to (137)Cs enriched soils. This is the first survey of gamma emitting radionuclides in Lombardia that is based on the LUCAS standard sampling. The results from this monitoring campaign are important for the human radiation exposure and provide the zero point, which will be useful for assessing future effects due to external factors such as human activities. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Mobility of gamma-emitting fission products in typical black and laterite soils

International Nuclear Information System (INIS)

D'Souza, T.J.; Mistry, K.B.

1981-01-01

Studies on the movement of the gamma-emitting fission products 106 Ru, 125 Sb, 137 Cs and 144 Ce, surface deposited on columns of the black and laterite soils revealed that the mobility of these nuclides in the two soils depended mainly on the ionic form of the nuclide, soil reaction and predominant clay mineral type in the soil. Results showed a rapid breakthrough of 106 Ru in the black soil and considerable migration to the lower layers in the laterite soil on leaching with rain water, or moderately high calcium or sodium irrigation waters. While near complete fixation of 144 Ce and 137 Cs in the top contaminated layer of both soils was observed, a slight movement of 125 Sb only in the black soil was noticed. Incorporation of organic matter had no effects on the movement of fission products in both soil types, whereas ethylenediaminetraacetic acid (EDTA) induced variable movement of the different radionuclides in the two soil types. (author)

Alpha-beta-gamma spectrometer as an aid in directing decontamination of soils

International Nuclear Information System (INIS)

Berger, C.D.

1981-01-01

This technique permits rapid assessment of alpha-beta-gamma-emitter contamination in soils at sufficiently low concentrations to direct field operations. Of particular importance is its applicability during initial decommissioning and decontamination surveys when characterization of alpha and beta contamination in the presence of a high gamma background is necessary. This system has not yet been made portable for in-situ use, but it is expected that results willbe favorable when operated as a field instrument, resulting in simplified standard decontamination operation

Deposition of gamma emitters from Chernobyl accident and their transfer in lichen-soil columns.

Science.gov (United States)

Lehto, Jukka; Paatero, Jussi; Pehrman, Reijo; Kulmala, Seija; Suksi, Juhani; Koivula, Teija; Jaakkola, Timo

2008-10-01

Lichen-soil column samples were taken from several locations in the Southern Finland between 1986 and 2006. Columns were divided into three parts, upper lichen, lower lichen and underlying soil, and their gamma emitting radionuclides, 134Cs, 137Cs, 103Ru, 95Zr, 106Ru, 110mAg, 125Sb and 144Ce, were measured with gamma spectrometry. Deposition values were calculated as Bq/m2 for each sampling site. Distribution of various radionuclides in the three compartments as a function of time was determined. Both effective and ecological half-lives of all radionuclides were calculated for upper lichen, whole lichen and whole lichen-soil column. A linear relation was derived between the physical half-lives and effective half-lives for whole lichen and for whole lichen-soil column. Reindeer meat activity concentrations of various radionuclides and ensuing radiation doses to reindeer-herding people were also estimated for a hypothetical case where a similar high radioactive pollution, as was taken place in the Southern Finland, would have occurred in the reindeer-herding areas in the Finnish Lapland.

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

International Nuclear Information System (INIS)

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

2015-01-01

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

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

International Nuclear Information System (INIS)

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

2010-12-01

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

Radon survey and soil gamma doses in primary schools of Batman, Turkey.

Science.gov (United States)

Damla, Nevzat; Aldemir, Kamuran

2014-06-01

A survey was conducted to evaluate levels of indoor radon and gamma doses in 42 primary schools located in Batman, southeastern Anatolia, Turkey. Indoor radon measurements were carried out using CR-39 solid-state nuclear track detector-based radon dosimeters. The overall mean annual (222)Rn activity in the surveyed area was found to be 49 Bq m(-3) (equivalent to an annual effective dose of 0.25 mSv). However, in one of the districts (Besiri) the maximum radon value turned out to be 307 Bq m(-3). The estimated annual effective doses are less than the recommended action level (3-10 mSv). It is found that the radon concentration decreases with increasing floor number. The concentrations of natural and artificial radioisotopes were determined using gamma-ray spectroscopy for soil samples collected in close vicinity of the studied schools. The mean gamma activity concentrations in the soil samples were 31, 25, 329 and 12 Bq kg(-1) for (226)Ra, (232)Th, (40)K and (137)Cs, respectively. The radiological parameters such as the absorbed dose rate in air and the annual effective dose equivalent were calculated. These radiological parameters were evaluated and compared with the internationally recommended values.

Beta and Gamma Gradients

DEFF Research Database (Denmark)

Løvborg, Leif; Gaffney, C. F.; Clark, P. A.

1985-01-01

Experimental and/or theoretical estimates are presented concerning, (i) attenuation within the sample of beta and gamma radiation from the soil, (ii) the gamma dose within the sample due to its own radioactivity, and (iii) the soil gamma dose in the proximity of boundaries between regions...... of differing radioactivity. It is confirmed that removal of the outer 2 mm of sample is adequate to remove influence from soil beta dose and estimates are made of the error introduced by non-removal. Other evaluations include variation of the soil gamma dose near the ground surface and it appears...... that the present practice of avoiding samples above a depth of 0.3 m may be over-cautious...

Gamma-spectrometric measurement of radioactivity in agricultural soils of the Lombardia region, northern Italy

International Nuclear Information System (INIS)

Guidotti, Laura; Carini, Franca; Rossi, Riccardo; Gatti, Marina; Cenci, Roberto M.; Beone, Gian Maria

2015-01-01

This work is part of a wider monitoring project of the agricultural soils in Lombardia, which aims to build a database of topsoil properties and the potentially toxic elements, organic pollutants and gamma emitting radionuclides that the topsoils contain. A total of 156 agricultural soils were sampled according to the LUCAS (Land Use/Cover Area frame statistical Survey) standard procedure. The aim was to provide a baseline to document the conditions present at the time of sampling. The results of the project concerning soil radioactivity are presented here. The aim was to assess the content of 238 U, 232 Th, 137 Cs and 40 K by measuring soil samples by gamma spectrometry. 238 U, 232 Th and 40 K activities range 24–231, 20–70, and 242–1434 Bq kg −1 respectively. The geographic distribution of 238 U reflects the geophysical framework of the Lombardia region: the soils with high content of uranium are distributed for the most part in the South Alpine belt, where the presence of magmatic rocks is widespread. These soils show an higher activity of 238 U than of 232 Th. The 238 U activities become lower than 232 Th when soils are located in the plain, originating from basic sedimentary rocks. 137 Cs activity ranges 0.4–86.8 kBq m −2 . The lowest activity of 137 Cs is in the plain, whereas the highest is in the North on soils kept as lawn or pasture. The 137 Cs activity of some samples suggests the presence of accumulation processes that lead to 137 Cs enriched soils. This is the first survey of gamma emitting radionuclides in Lombardia that is based on the LUCAS standard sampling. The results from this monitoring campaign are important for the human radiation exposure and provide the zero point, which will be useful for assessing future effects due to external factors such as human activities. - Highlights: • A monitoring campaign of agricultural soils was carried out in Lombardia, Italy. • 156 topsoils were sampled according to the European standard

Gamma-emissions of some meteorites and terrestrial rocks. Evaluation of lunar soil radioactivity; Emissions gamma de quelques meteorites et roches terrestres. Evaluation de la radioactivite du sol lunaire

Energy Technology Data Exchange (ETDEWEB)

Nordemann, D. [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

1966-07-01

The gamma-emissions of some terrestrial rocks and of the following meteorites: Bogou, Eagle-Station, Granes, and Dosso were studied by quantitative low background gamma spectrometry. These measurements and their interpretation lead to the evaluation of the possible gamma-emissions of several models of lunar soils. (author) [French] Les emissions gamma des meteorites Bogou, Eagle-Station, Granes et Dosso et de quelques roches terrestres ont ete etudiees par spectrometrie gamma quantitative a faible mouvement propre. Ces mesures et leur interpretation permettent d'evaluer les principales contributions des emissions gamma du sol lunaire pour des modeles de compositions possibles variees. (auteur)

Gamma-emissions of some meteorites and terrestrial rocks. Evaluation of lunar soil radioactivity; Emissions gamma de quelques meteorites et roches terrestres. Evaluation de la radioactivite du sol lunaire

Energy Technology Data Exchange (ETDEWEB)

Nordemann, D [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

1966-07-01

The gamma-emissions of some terrestrial rocks and of the following meteorites: Bogou, Eagle-Station, Granes, and Dosso were studied by quantitative low background gamma spectrometry. These measurements and their interpretation lead to the evaluation of the possible gamma-emissions of several models of lunar soils. (author) [French] Les emissions gamma des meteorites Bogou, Eagle-Station, Granes et Dosso et de quelques roches terrestres ont ete etudiees par spectrometrie gamma quantitative a faible mouvement propre. Ces mesures et leur interpretation permettent d'evaluer les principales contributions des emissions gamma du sol lunaire pour des modeles de compositions possibles variees. (auteur)

The application of high-speed photography and spectrography for investigations of erosive pulsed plasma streams

International Nuclear Information System (INIS)

Kiselevskiy, L.I.; Minko, L.Ja.

The extensive information of pulsed plasma dynamic processes related to formation and interaction of plasma streams with a surrounding medium and obstacles is obtained with the help of high-speed photo and spectrography. The wave structure of pulsed supersonic under-expanded erosive plasma jets is studied. Some physical processes which are due to interactions of laser radiation with the laser-produced erosive plasma and of this plasma with a surrounding medium are investigated. The wide possibilities of frame photography of spectra quantitative spectroscopic investigations of fast-proceeding plasma processes are shown on the basis of joint use of high-speed photographic apparatus (type SFR) and standard spectrographs. The radial distribution of charged-particle concentrations at separate moments of time is obtained from the broadening of spectral lines at the brightness of the continuous spectrum of an erosive plasma jet from a pulsed accelerator

Study of stability of humic acids from soil and peat irradiated by gamma rays

International Nuclear Information System (INIS)

Silva, Wilson Tadeu Lopes da

1995-01-01

Humic acids samples (one deriving from a sedimentary soil and other from a peat), in aqueous media, were irradiated with gamma rays, in doses of 10, 50 and 100 kGy, in order to understand their chemical behavior after the irradiation. The material, before and after irradiation, was analyzed by Elemental Analysis, Functional Groups (carboxylic acids and phenols), UV/Vis Spectroscopy (E 4 /E 6 ratio), IR spectroscopy, CO 2 content and Gel permeation Chromatography (GPC) ). The Elemental Analysis showed the humic acid derived from a peat had a most percentage quantity of Carbon and Hydrogen than the material from a sedimentary soil. From the UV/Vis Spectroscopy, it was observed a decrease of E 4 /E 6 ratio with an increase of the applied dose. The data from GPC are in agreement with this. The results showed that the molecular weight of the material increased by exposing it to a larger radiolitical dose. The peat material was less affected by the gamma radiation than the soil material. The carboxylic groups were responsible by radiochemical behavior of the material. (author)

Efficiency calibration and measurement of self-absorption correction of environmental gamma spectroscopy of soils samples using Marinelli beaker

International Nuclear Information System (INIS)

Abdi, M. R.; Mostajaboddavati, M.; Hassanzadeh, S.; Faghihian, H.; Rezaee, Kh.; Kamali, M.

2006-01-01

A nonlinear function in combination with the method of mixing activity calibrated is applied for fitting the experimental peak efficiency of HPGe spectrometers in 59-2614 keV energy range. The preparation of Marinelli beaker standards of mixed gamma and RG-set at secular equilibrium with its daughter radionuclides was studied. Standards were prepared by mixing of known amounts of 13B a, 241 Am, 152 Eu, 207 Bi, 24 Na, Al 2 O 3 powder and soil. The validity of these standards was checked by comparison with certified standard reference material RG-set and IAEA-Soil-6 Self-absorption was measured for the activity calculation of the gamma-ray lines about series of 238 U daughter, 232 Th series, 137 Cs and 40 K in soil samples. Self-absorption in the sample will depend on a number of factor including sample composition, density, sample size and gamma-ray energy. Seven Marinelli beaker standards were prepared in different degrees of compaction with bulk density ( ρ) of 1.000 to 1.600 g cm -3 . The detection efficiency versus density was obtained and the equation of self-absorption correction factors calculated for soil samples

Remediation of soil contaminated with pesticides by treatment with gamma radiation

International Nuclear Information System (INIS)

Santos, Janilson Silva

2009-01-01

The discharge of empty plastic packaging of pesticides can be an environmental concern mainly by soil contamination. Nowadays, Brazil figures in third place among the leading world pesticide markets. An understanding of the processes that affect the transport and fate of pesticides is crucial to assess their potential for contamination of soil and groundwater, and to develop efficient and cost-effective site management and soil remediation strategies. Due to its impact on soil remediation has made sorption a major topic of research on soil-pesticide interactions. The main objective of this study is the evaluation of the pesticides transferring from contaminated mixture of commercial polymeric packing of high-density polyethylene, HDPE, used in agriculture to soil and their removal by gamma irradiation. Two soil samples of argyles compositions and media composition were exposed to a mixture of commercial polymeric packing contaminated with the pesticides methomyl, dimethoate, carbofuran, methidathion, triazine, thiophos, atrazine, ametryne, endosulfan, chloropyrifos, thriazophos and trifluralin. The pesticides leaching from packaging to soil was homogeneous considering a experimental research. The radiation treatment presented high efficiency on removal pesticides from both soil, but it depends on the physical-chemical characteristics of the contaminated soil. The higher efficiency was obtained in soils with higher organic material and humidity. The higher efficiency was obtained for the medium texture soil, with 20 kGy all present pesticides were removed in all layers. In the case of argyles texture soil, it was necessary a 30 kGy to remove the totality of present pesticides. (author)

Effect of collimator size and absorber thickness on soil bulk density evaluation by gamma-ray attenuation

International Nuclear Information System (INIS)

Costa, J.C.; Borges, J.A.R.; Pires, L.F.

2014-01-01

Representative measurements of the soil bulk density (ρ s ) can be affected depending on the geometry selected for gamma-ray attenuation (GRA) measurements. In this study, the effect of collimator size (2–4 mm diameters) and absorber thickness (2–15 cm) on ρ s measurements of sandy and clayey soils was investigated. In summary, the results obtained for the 137 Cs show that ρ s remained fairly constant for values of thickness larger than 7 cm (both soils). The very same result was observed for collimator sizes 2–4 mm. Regarding the 241 Am source, ρ s values presented variations with the collimator size (both soils) for the different thicknesses. The best values of ρ s were obtained for samples smaller than 5 cm and also for the small collimator diameters. - Highlights: ► Representative measurements of the soil bulk density by gamma-ray attenuation. ► For 137 Cs the best bulk density values were obtained for samples larger than 7 cm. ► For 241 Am the best bulk density values were obtained for samples smaller than 5 cm

Determination of residual boron in thermally treated controlled-porosity glasses, by colorimetry, spectrography and isotachophoresis

International Nuclear Information System (INIS)

Dawidowicz, A.L.; Matusewicz, J.; Wysocka-Lisek, J.

1989-01-01

Controlled-porosity glasses (CPGs) are often applied as sorbents in chromatography. Besides having high thermal, chemical and mechanical resistance they are characterized by a very narrow pore-size distribution and the choice of mean pore diameter and porosity covers a wide range. In spite of these advantages, their range of use in chromatography is restricted because of their strong adsorption properties, which are connected with the presence of residual boron atoms in the porous CPG skeleton. The boron concentration on the CPG surface can be increased by proper thermal treatment. When CPGs are heated in the range 400-800 0 the residual boron atoms in the network diffuse from the bulk to the surface. The paper discusses the boron content in porous glasses of different mean pore diameters and the determination of the enrichment of boron on the GPG surface, by three independent methods: colorimetry, spectrography and isotachophoresis. (author)

Hydraulic conductivity of indeformed soil columns determination by gamma ray transmission

International Nuclear Information System (INIS)

Moreira, Anderson Camargo; Moraes Cavalcante, Fabio Henrique de; Rocha, Marcos Correa da; Filho, Otavio Portezan; Quinones, Fernando Rodolfo Espinosa; Appoloni, Carlos Roberto

2000-01-01

The spatial variation of the soil structure influences the water movement through its porous geometry, which could cause problems in the development of agricultural cultures and also accelerate processes of soil erosion. The gamma ray transmission method has established efficiency for the non-destructive measurement of moisture temporal and space evolution, and consequently in the determination of the hydraulic conductivity of the soil, K(θ). Columns of undisturbed soil (approximately 0.11 x 0.06 x 0.60 m) were removed from a trench in the Campus of Londrina State University. The used soil was classified like distrophic dark red soil (LRd). The indeformed soil columns were wrapped up with paraffin and gauze and were fixed on the table of measurement. The water vertical infiltration in the soil was accomplished by maintaining a water layer of approximately 0.01 m over an area of soil of 75 x 10 -4 m 2 . Layers of filter papers and foam controlled the flow of water in the soil surface. After the conclusion of the infiltration, began the process of redistribution of the water in the soil column, with the objective to determine the function K(θ) in relation to the depth in the column. The moisture profiles θ(z,t) are obtained using a radioactive source of 241 Am (3.7 x 10 9 Bq; 0.0596 MeV), spectrometric electronic chain, a 2x2'' NaI(Tl) detector and a measurements table , which allows the sample to move vertically. The hydraulic conductivity function was determined, applying the Sisson model , at 10 levels in the soil column and the results exhibit an increase of K(θ) with depth. (author)

Gamma ray transmission for hydraulic conductivity measurement of undisturbed soil columns

Directory of Open Access Journals (Sweden)

Anderson Camargo Moreira

2007-03-01

Full Text Available This work had the objective to determine the Hydraulic Conductivity K(theta function for different depth levels z, of columns of undisturbed soil, using the gamma ray transmission technique applied to the Sisson method. The results indicated a growing behavior for K(theta and a homogeneous soil density, both in relation to the increase of the depth. The methodology of gamma ray transmission showed satisfactory results on the determination of the hydraulic conductivity in columns of undisturbed soil, besides being very reliable and a nondestructive method.O estudo da condutividade hidráulica para solos não saturados é essencial quando aplicado às situações relacionadas à irrigação, drenagem e transporte de nutrientes no solo, é uma importante propriedade para desenvolvimentos de culturas agrícolas. Este trabalho tem o objetivo de determinar a função Condutividade Hidráulica K(teta, em diferentes níveis z de profundidade, em colunas de solo indeformado, utilizando a transmissão de raios gama aplicada ao método de Sisson. Os resultados indicam um comportamento crescente para K(teta e uma densidade de solo homogênea, ambos em relação ao aumento da profundidade. A metodologia de transmissão de raios gama mostrou resultados bastante satisfatórios na determinação da condutividade hidráulica em colunas de solo indeformado, além de ser muito confiável e não destrutivo.

Measurement of gamma-ray dose rate in soil and transfer of radionuclides from soil to vegetation

International Nuclear Information System (INIS)

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

2012-01-01

Analysis of natural radionuclides in soil, vegetation and vegetable samples collected from some Northern areas of Pakistan was carried out by gamma -ray spectrometry (HPGe detector). The activity concentrations in soil ranged from 24.7 to 78.5 Bqkg/sup -1/, 21.7 to 75.3 Bqkg/sup -1/ and 298.5 to 570.8 Bqkg/sup -1/ for /sup 226/Ra, /sup 232/Th, and /sup 40/K with the mean values of 42.1, 43.3 and 418.3 Bqkg/sup -1/, respectively. In the present analysis, /sup 40/K was the major radionuclide present in soil, vegetation, fruit and vegetable samples. The transfer factors of these radionuclides from soil to vegetation, fruit and vegetable were found in the order: /sup 40/K>/sup 232/Th>/sup 226/Ra. The mean value of outdoor and indoor absorbed dose rate (D) in air was 64.61 and 77.54 nGyh/sup -1/. The activity concentrations of radionuclides found in all samples were nominal. Therefore, they are not associated with any potential source of health hazard to the general public. (Orig./A.B.)

STUDY CONCERNING THE POSSIBILITY OF GAMMA-SPECTROSCOPY METHOD TO DETERMINE THE TOTAL POTASSIUM IN SOILS

Directory of Open Access Journals (Sweden)

Tamara Leah

2011-12-01

Full Text Available It was proved the possibility of determination the total potassium in soils by gamma-spectroscopic method with subsequent calculation of total potassium content in according to value of 40K isotope (expressed in Becquerel, Bq, using the formula: К2О, % = С . А, where: C – conversion coefficient, A – activity of isotope 40K in soil, Bq/kg. Conversion coefficient for chernozems of Moldova – C=0,00337.

Soil nutrient content of old-field and agricultural ecosystems exposed to chronic gamma irradiation

International Nuclear Information System (INIS)

Armentano, T.V.; Holt, B.R.; Bottino, P.J.

1975-01-01

Soil nutrients (extractable P. and NO 3 -N, exchangeable Ca, Mg and K), exchangeable Al, pH and organic matter content were measured over the top six inches of the soils of the seven-year old-field portion and the cultivated portion of the Brookhaven gamma field. Although concentrations of all nutrient elements were higher in the agricultural soil, the distributions of Ca, P, Al, pH and organic matter were similar along the radiation gradient in both fields. There was also a regular reduction in the phosphorus with decreasing exposure, but distribution of other elements was not clearly related to radiation effects. The distribution of all elements except K was significantly correlated with pH in the agricultural soil. In the old-field only Ca, Mg and Al showed this relationship. The most conspicuous effects of nearly 25 yr of chronic irradiation of the site were a reduction in soil organic matter content and an increase in soil P in both fields. (author)

Chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade uranyl nitrate solutions

International Nuclear Information System (INIS)

Anon.

1981-01-01

The standard covers analytical procedures to determine compliance of nuclear-grade uranyl nitrate solution to specifications. The following methods are described in detail: uranium by ferrous sulfate reduction-potassium dichromate titrimetry and by ignition gravimetry; specific gravity by pycnometry; free acid by oxalate complexation; thorium by the Arsenazo(III) (photometric) method; chromium by the diphenylcarbazide (photometric) method; molybdenum by the thiocyanate (photometric) method; halogens separation by steam distillation; fluorine by specific ion electrode; halogen distillate analysis: chloride, bromide and iodide by amperometric microtitrimetry; bromine by the fluorescein (photometric) method; sulfate sulfur by (photometric) turbidimetry; phosphorus by the molybdenum blue (photometric) method; silicon by the molybdenum blue (photometric) method; carbon by persulfate oxidation-acid titrimetry; nonvolatile impurities by spectrography; volatile impurities by rotating-disk spark spectrography; boron by emission spectrography; impurity elements by spark source mass spectrography; isotopic composition by multiple filament surface-ionization mass spectrometry; uranium-232 by alpha spectrometry; total alpha activity by direct alpha counting; fission product activity by beta and gamma counting; entrained organic matter by infrared spectrophotometry

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

International Nuclear Information System (INIS)

Mohamed, Yousif Hassab El Rasoul

1997-05-01

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

Gamma spectroscopy analysis of archived Marshall Island soil samples

International Nuclear Information System (INIS)

Herman, S.; Hoffman, K.; Lavelle, K.; Trauth, A.; Glover, S.E.; Connick, W.; Spitz, H.; LaMont, S.P.; Hamilton, T.

2016-01-01

Four samples of archival Marshall Islands soil were subjected to non-destructive, broad energy (17 keV-2.61 MeV) gamma-ray spectrometry analysis using a series of different high-resolution germanium detectors. These archival samples were collected in 1967 from different locations on Bikini Atoll and were contaminated with a range of fission and activation products, and other nuclear material from multiple weapons tests. Unlike samples collected recently, these samples have been stored in sealed containers and have been unaffected by approximately 50 years of weathering. Initial results show that the samples contained measurable but proportionally different concentrations of plutonium, 241 Am, and 137 Cs, and 60 Co. (author)

Natural gamma radioactivity and of 137 Cs in soil of the Chimaltitan municipality, Jalisco, Mexico

International Nuclear Information System (INIS)

Garay, A.; Mireles, F.; Quirino, L.L.; Davila, J.I.; Rios, C.; Lugo, J.F.; Soriano, J.M.; Angoli, A.

2003-01-01

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

Natural {gamma}-radiation of rocks and soils from Vulcano (Aeolian Islands, Mediteranean Sea)

Energy Technology Data Exchange (ETDEWEB)

Brai, M. [Palermo Univ. (Italy). Ist. della Biocomunicazione; Hauser, S.; Bellia, S. [Palermo Univ. (Italy). Ist. di Mineralogia, Petrografia e Geochimica; Puccio, P.; Rizzo, S. [Palermo Univ. (Italy). Dipt. di Ingegneria Nucleare

1995-04-01

Gamma-ray spectra of the main lithotypes and soils from Vulcano island (Mediterranean Sea) have been carried out in order to quantify the natural radioactivity. The {sup 238}U, {sup 232}Th, and {sup 40}K contents obtained are in agreement with the genesis of the rock formation. In fact, basaltic rocks showed the lowest content of radionuclides whereas the rhyolitic rocks showed the highest concentrations. The results are comparable with other volcanic areas of southern Italy. Measurements of absorbed dose in air by TL dosimeters were also performed. The values ranged between 0.5 and 2.0 mGy y{sup -1}. Comparison between these values and those computed from {gamma}-ray spectra showed a good correlation. (author).

Soil gamma ray spectrometry of the Buquira river basin, SP, Brazil

International Nuclear Information System (INIS)

Rivera, Alice

2002-12-01

Natural radioactivity found in rocks and its evaluation been frequently used for studies of environmental geochemistry, particularly those of detection and control of pollutants and the consequent changes in environment after antropic interferences. In this work natural radioactivity in forty nine soil samples in the basin of Buquira river, at the Northeast region of Sao Paulo State, has been analysed and measured with a Ge-HP gamma ray spectrometer. A table with the most relevant results found in rocks is shown and discussed. (author)

Radioactivity Levels And Gamma Dose Rate In Soil Samples From Federation Of Bosnia And Herzegovina

International Nuclear Information System (INIS)

Deljkic, D.; Kadic, I.; Ilic, Z.; Vidic, A.

2015-01-01

Activity concentrations of 226Ra, 232Th, 40K and 137Cs in soil samples collected from different regions of Federation of Bosnia and Herzegovina have been measured by gamma-ray spectrometry. The measured activity concentrations for these radionuclides are compared with the reported data from different other countries and it is found that measured activity concentrations are comparable with the worldwide measured average values reported by the UNSCEAR. Experimental results were obtained by using a high-purity germanium (HPGe) detector and gamma - ray spectrometry analysis system at Institute for Public Health FBiH (Radiation Protection Center). The measuring time of all soil samples was 86000 seconds. It was found that the soil specific activity ranges from 24.59 to 161.20 Bq/kg for 226Ra, from 17.60 to 66.45 Bq/kg for 232Th, from 179.50 to 598.04 Bq kg-1 for 40K and from 11.13 to 108.69 Bq/kg for 137Cs with the mean values of 62.34; 46.97; 392.76 and 51.49 Bq/kg, respectively. The radium equivalent activity in all the soil samples is lower than the safe limit (370 Bq/kg), ranges from 63.58 to 287.03 Bq/kg with the mean value of 159.71 Bq/kg. Man-made radionuclide 137Cs is also present in detectable amount in all soil samples. Presence of 137Cs indicates that the samples in this area also receive some fallout from nuclear accident in Chernobyl power plant in 1986. The value of external radiation hazard indices is found to be less than unity (mean value of 0.43). 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 does not pose any potential health hazard to the general public. (author).

Focal plane detector for QDD spectrography in Institute of Nuclear Study and detector for SMART 2nd focal plane in RIKEN

Energy Technology Data Exchange (ETDEWEB)

Fuchi, Yoshihide [Tokyo Univ., Tanashi (Japan). Inst. for Nuclear Study

1996-09-01

The focal plane detector for QDD spectrography in Institute of Nuclear Study was composed of drift space and a proportional counter tube, and the latter is composed of position detector and two delta E detector for recognizing the particles. In this detector, a uniform parallel electric field can be obtained by placing a guard plate at the same height as that of a drift plate outer place of the detector. On the other hand, the detector for SMART 2nd focal plate in RIKEN is composed of drift space and a single wire proportional counter, and has two cathode read out single wire drift counters set so as to hold the focal plane. (G.K.)

A first attempt to derive soil erosion rates from 137Cs airborne gamma measurements in two Alpine valleys

Science.gov (United States)

Arata, Laura; Meusburger, Katrin; Bucher, Benno; Mabit, Lionel; Alewell, Christine

2016-04-01

The application of fallout radionuclides (FRNs) as soil tracers is currently one of the most promising and effective approach for evaluating soil erosion magnitudes in mountainous grasslands. Conventional assessment or measurement methods are laborious and constrained by the topographic and climatic conditions of the Alps. The 137Cs (half-life = 30.2 years) is the most frequently used FRN to study soil redistribution. However the application of 137Cs in alpine grasslands is compromised by the high heterogeneity of the fallout due to the origin of 137Cs fallout in the Alps, which is linked to single rain events occurring just after the Chernobyl accident when most of the Alpine soils were still covered by snow. The aim of this study was to improve our understanding of the 137Cs distribution in two study areas in the Central Swiss Alps: the Ursern valley (Canton Uri), and the Piora valley (Canton Ticino). In June 2015, a helicopter equipped with a NaI gamma detector flew over the two study sites and screened the 137Cs activity of the top soil. The use of airborne gamma measurements is particularly efficient in case of higher 137Cs concentration in the soil. Due to their high altitude and high precipitation rates, the Swiss Alps are expected to be more contaminated by 137Cs fallout than other parts of Switzerland. The airborne gamma measurements have been related to several key parameters which characterize the areas, such as soil properties, slopes, expositions and land uses. The ground truthing of the airborne measurements (i.e. the 137Cs laboratory measurements of the soil samples collected at the same points) returned a good fit. The obtained results offer an overview of the 137Cs concentration in the study areas, which allowed us to identify suitable reference sites, and to analyse the relationship between the 137Cs distribution and the above cited parameters. The authors also derived a preliminary qualitative and a quantitative assessment of soil redistribution

Spasmodic dysphonia follow-up with videolaryngoscopy and voice spectrography during treatment with botulinum toxin.

Science.gov (United States)

Esposito, Marcello; Dubbioso, R; Apisa, P; Allocca, R; Santoro, L; Cesari, U

2015-09-01

Spasmodic dysphonia (SD) is a focal dystonia of laryngeal muscles seriously impairing quality of voice. Adductor SD (ADSD) is the most common presentation of this disorder that can be identified by specialized phoniatricians and neurologists firstly on a clinical evaluation and then confirmed by videolaryngoscopy (VL). Botulinum toxin (BTX) injection with electromyographic guidance in muscles around vocal cords is the most effective treatment. Voice Handicap Index (VHI) questionnaire is the main tool to assess dysphonia and response to treatment. Objective of this study is to perform VL and voice spectrography (VS) to confirm the efficacy of BTX injections over time. 13 patients with ADSD were studied with VHI, VL and VS before and after 4 consecutive treatment with onobotulinumtoxin-A. For each treatment vocal improvement was proved by a significant reduction of VHI score and increase of maximum time phonation and harmonic-to-noise ratio while VL showed the absence of spasm in most of patients. No change of the response to BTX was found between injections. This study supports the efficacy of the treatment of SD with BTX with objective measurements and suggests that the efficacy of recurring treatments is stable over time.

Natural gamma radiation levels, indoor and water 222RN Concentrations in soil division of Kerio valley, kenya

International Nuclear Information System (INIS)

Nderitu, S.K.; Maina, D.M.; Kinyua, A.M.

2001-01-01

Human beings are constantly exposed to natural radioactivity. This radiation is mainly from natural gamma rays and radon and its decay products. The gamma rays are as a result of the decay of primordial nuclides and their daughter radioactive nuclides present in the earth's crust. Radon is produced from the decay of 226 Ra and it diffuses to the indoor environment through cracks on the floor or from building materials containing radium and hence radon problem is mainly indoors. In Kenya, some parts have been identified as having high gamma radiation causing exposure to the public. These areas include Mrima Hill (Kwale), Homa Bay, Bufayo, Weast Pokot, Kitui, Nanyuki, Kerio Valley and Tura. It is therefore necessary to carry out studies on the levels of radiation and determine whether they are within safe limits. Kerio valley, which is the area of study in this work, has been identified as one of the areas with uranium traces associated with fluorite mineralisation. In this study an assessment of the natural radiation levels in this area was carried out and in addition the radon concentrations indoor as well in water that the public is exposed were determined. To measure the radiation levels, soil samples were collected from the area of study, Kerio valley, and analysed for gamma levels using gamma spectroscopy technique. Indoor 222 Rn and radon in water concentrations were measured using the E-perm system. The activity concentrations of the radionuclides present, the doses as well as the annual effective dose equivalents were calculated for the soils using conversion factors adopted from the UNSCEAR (1988 and 1993) reports. Similarly, the dose equivalents and the annual effective doses for 222 Rn concentrations were evaluated. For natural gamma radiation 74 samples were analysed. The soil samples yielded activity concentrations ranging from 194.54??2.89 to 995.77??5.48 Bq Kg-1 for 40 K, 17.04??0.43 to 122.4??0.94 Bq Kg-1 for 232 Th which was evaluated from the 212

Radioactivity measurements in soils surrounding four coal-fired power plants in Serbia by gamma-ray spectrometry and estimated dose

Directory of Open Access Journals (Sweden)

Vukašinović Ivana Ž.

2014-01-01

Full Text Available The study of spatial distribution of activity concentration of 238U, 226Ra, 210Pb, 232Th, 40K, and 137Cs radionuclides in the surface soil samples (n = 42 collected in the vicinity of four coal-fired power plants in Serbia is presented. Radioactivity measurements in soils performed by gamma-ray spectrometry showed values [Bqkg-1] in the range: 15-117 for 238U, 21-115 for 226Ra, 33-65 for 210Pb, 20-69 for 232Th, 324-736 for 40K, and 2-59 for 137Cs. Surface soil radio-activity that could have resulted from deposition of radionuclides from airborne discharges or resuspension of ash from disposal sites showed no enhanced levels. It was found that variation of soil textural properties, pH values, and carbonate content influenced activity levels of natural radionuclides while radiocesium activities were associated with soil organic matter content. Modification of some soil properties was observed in the immediate vicinity (<1 km of power plants where the soil was more alkaline with coarser particles (0.2-0.05 mm and carbonates accumulated. Calculated average values of the absorbed gamma dose rate and annual external effective dose originating from the terrestrial radionuclides were 69.4 nGy/h and 0.085 mSv, respectively. [Projekat Ministarstva nauke Republike Srbije, br. 4007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation

Radon flux maps for the Netherlands and Europe using terrestrial gamma radiation derived from soil radionuclides

Science.gov (United States)

Manohar, S. N.; Meijer, H. A. J.; Herber, M. A.

2013-12-01

Naturally occurring radioactive noble gas, radon (222Rn) is a valuable tracer to study atmospheric processes and to validate global chemical transport models. However, the use of radon as a proxy in atmospheric and climate research is limited by the uncertainties in the magnitude and distribution of the radon flux density over the Earth's surface. Terrestrial gamma radiation is a useful proxy for generating radon flux maps. A previously reported radon flux map of Europe used terrestrial gamma radiation extracted from automated radiation monitoring networks. This approach failed to account for the influence of local artificial radiation sources around the detector, leading to under/over estimation of the reported radon flux values at different locations. We present an alternative approach based on soil radionuclides which enables us to generate accurate radon flux maps with good confidence. Firstly, we present a detailed comparison between the terrestrial gamma radiation obtained from the National Radiation Monitoring network of the Netherlands and the terrestrial gamma radiation calculated from soil radionuclides. Extending further, we generated radon flux maps of the Netherlands and Europe using our proposed approach. The modelled flux values for the Netherlands agree reasonably well with the two observed direct radon flux measurements (within 2σ level). On the European scale, we find that the observed radon flux values are higher than our modelled values and we introduce a correction factor to account for this difference. Our approach discussed in this paper enables us to develop reliable and accurate radon flux maps in countries with little or no information on radon flux values.

SOILD: A computer model for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil

International Nuclear Information System (INIS)

Chen, S.Y.; LePoire, D.; Yu, C.; Schafetz, S.; Mehta, P.

1991-01-01

The SOLID computer model was developed for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil. It is designed to assess external doses under various exposure scenarios that may be encountered in environmental restoration programs. The models four major functional features address (1) dose versus source depth in soil, (2) shielding of clean cover soil, (3) area of contamination, and (4) nonuniform distribution of sources. The model is also capable of adjusting doses when there are variations in soil densities for both source and cover soils. The model is supported by a data base of approximately 500 radionuclides. 4 refs

In situ-observation of the vertical motion of soil waters by means of deuterated water using the gamma/neutron method: Laboratory and field

International Nuclear Information System (INIS)

Moutonnet, P.; Couchat, P.; Brissaud, F.; Puard, M.; Pappalardo, A.

1978-01-01

In order to study water movements in the field, the gamma/neutron method for measuring deuterated water was investigated. A laboratory device is presented which supplies measurements on 5 ml soil solution samples. A probe for in situ experiments is studied in all its performances: Background, calibration (count rate versus volumetric deuterated water content) and resolution. A dispersive transport of D 2 O pulses on soil column is presented and checked with a numerical simulation model. Then simultaneous measurement of soil water content and D 2 O concentration by neutron moisture gauge and gamma/neutron probe enable us to interpret the evolution of D 2 O pulse with an experimental field irrigation. (orig.) [de

Validation of a model for calculating environmental doses caused by gamma emitters in the soil

International Nuclear Information System (INIS)

Ortega, X.; Rosell, J.R.; Dies, X.

1991-01-01

A model has been developed to calculate the absorbed dose rates caused by gamma emitters of both natural and artificial origin distributed in the soil. The model divides the soil into five compartments corresponding to layers situated at different depths, and assumes that the concentration of radionuclides is constant in each one of them. The calculations, following the model developed, are undertaken through a program which, based on the concentrations of the radionuclides in the different compartments, gives as a result the dose rate at a height of one metre above the ground caused by each radionuclide and the percentage this represents with respect to the total absorbed dose rate originating from this soil. The validity of the model has been checked in the case of sandy soils by comparing the exposure rates calculated for five sites with the experimental values obtained with an ionisation chamber. (author)

Dosimetry for terrestrial gamma-ray sources

International Nuclear Information System (INIS)

Abdullah, S.A.; Dickson, H.W.; Kerr, G.D.; Miah, M.F.K.; Perdue, P.T.

1975-01-01

Dose rates from natural radionuclides and 137 Cs in soils of the Oak Ridge area have been determined from in situ and core sample measurements. Information on soil composition, density, and moisture content and on the distribution of cesium in the soil was obtained from the core samples. Measurements of radionuclide concentrations in the samples were made with a 4 x 4 in. NaI detector. Gamma-ray spectroscopy using a lithium-drifted germanium (GeLi) detector has been applied to the determination of radionuclide concentrations in soil and the associated gamma dose rates above the earth plane. An unshielded GeLi detector placed about 1 m above the earth detects gamma radiation from an area of about 100 m 2 . The equipment and data processing procedure are briefly described

Airborne gamma-ray and magnetic anomaly signatures of serpentinite in relation to soil geochemistry, northern California

Science.gov (United States)

McCafferty, A.E.; Van Gosen, B. S.

2009-01-01

Serpentinized ultramafic rocks and associated soils in northern California are characterized by high concentrations of Cr and Ni, low levels of radioelements (K, Th, and U) and high amounts of ferrimagnetic minerals (primarily magnetite). Geophysical attributes over ultramafic rocks, which include airborne gamma-ray and magnetic anomaly data, are quantified and provide indirect measurements on the relative abundance of radioelements and magnetic minerals, respectively. Attributes are defined through a statistical modeling approach and the results are portrayed as probabilities in chart and map form. Two predictive models are presented, including one derived from the aeromagnetic anomaly data and one from a combination of the airborne K, Th and U gamma-ray data. Both models distinguish preferential values within the aerogeophysical data that coincide with mapped and potentially unmapped ultramafic rocks. The magnetic predictive model shows positive probabilities associated with magnetic anomaly highs and, to a lesser degree, anomaly lows, which accurately locate many known ultramafic outcrops, but more interestingly, locate potentially unmapped ultramafic rocks, possible extensions of ultramafic bodies that dip into the shallow subsurface, as well as prospective buried ultramafic rocks. The airborne radiometric model shows positive probabilities in association with anomalously low gamma radiation measurements over ultramafic rock, which is similar to that produced by gabbro, metavolcanic rock, and water bodies. All of these features share the characteristic of being depleted in K, Th and U. Gabbro is the only rock type in the study area that shares similar magnetic properties with the ultramafic rock. The aerogeophysical model results are compared to the distribution of ultramafic outcrops and to Cr, Ni, K, Th and U concentrations and magnetic susceptibility measurements from soil samples. Analysis of the soil data indicates high positive correlation between

Preliminary results on soil-emitted gamma radiation and its relation with the local atmospheric electric field at Amieira (Portugal)

International Nuclear Information System (INIS)

Lopes, F; Barbosa, S M; Silva, H G; Bárias, S

2015-01-01

The atmospheric electric field near the Earth's surface is dominated by atmospheric pollutants and natural radioactivity, with the latter directly linked to radon ( 222 Rn) gas. For a better comprehension on the temporal variability of both the atmospheric electric field and the radon concentration and its relation with local atmospheric variables, simultaneous measurements of soil-emitted gamma radiation and potential gradient (defined from the vertical component of the atmospheric electric field) were taken every minute, along with local meteorological parameters (e.g., temperature, atmospheric pressure, relative humidity and daily solar radiation). The study region is Amieira, part of the Alqueva lake in Alentejo Portugal, where an interdisciplinary meteorological campaign, ALEX2014, took place from June to August 2014. Soil gamma radiation is more sensitive to small concentrations of radon as compared with alpha particles measurements, for that reason it is more suited for sites with low radon levels, as expected in this case. Preliminary results are presented here: statistical and spectral analysis show that i) the potential gradient has a stronger daily cycle as compared with the gamma radiation, ii) most of the energy of the gamma signal is concentrated in the low frequencies (close to 0), contrary to the potential gradient that has most of the energy in frequency 1 (daily cycle) and iii) a short-term relation between gamma radiation and the potential gradient has not been found. Future work and plans are also discussed. (paper)

Elemental analysis of water and soil environmental samples in Tabuk area by neutron capture gamma-ray spectroscopy techniques

International Nuclear Information System (INIS)

Al-Aseery, Sh.M.; Alamoudi, Z.; Hassan, A.M.

2006-01-01

The prompt and delayed gamma-rays due to neutron capture in the nuclei of the constituent elements of three soil samples and one drinking water sample have been measured. The 252 Cf and 226 Ra/Be isotopic neutron sources are used for neutron irradiation. Also, the hyper pure germanium detection system is used. The soil samples were from Astra, Tadco and El-Gammaz farms, while the water sample was taken from Tabuk city. In case of prompt gamma-ray analysis, a total of 16 elements were identified and the concentration percentage values by weight were calculated for: C, Na, Mg, Al, Si, S, Cl,, Ca, Ti, Cr, Mn, Fe, Co, Zn, Sr ad Pb elements. A comparative study between the results obtained in this work and the results obtained by ICP-MS and EDX-Ray techniques for the same samples is given

Evaluation of the synergistic effect of gamma irradiated Steinernema scapterisci and soil depth in controlling Bactrocera zonata Saunders (Diptera: Tephritidae

Directory of Open Access Journals (Sweden)

R.M. Sayed

2018-01-01

Full Text Available The Peach fruit fly, Bactrocera zonata (Saunders is a serious devastating pest in Egypt. This pest spends in soil from full grown larvae till adult emergence. Therefore, the present study was planned to evaluate the pathogenicity of Steinernema scapterisci against larvae and 1 day old pupae (at different soil depths, and to investigate the effect of gamma radiation on its virulence. The results revealed that adult emergence percentage decrease as the soil depth and S. scapterisci concentration increase. In contrast, the larval mortality increased with S. scapterisci concentration increased. In addition, this study showed that gamma irradiation of S. scapterisci juveniles with 2Gy increased its virulence against both larvae and pupae, which presented by lower LC50 values than unirradiated S. scapterisci. Subsequently, it could be concluded that 2Gy irradiated S. scapterisci can serve as a bio-tolerated control method for B. zonata.

A GIS model-based assessment of the environmental distribution of gamma-hexachlorocyclohexane in European soils and waters.

Science.gov (United States)

Vizcaíno, P; Pistocchi, A

2010-10-01

The MAPPE GIS based multimedia model is used to produce a quantitative description of the behaviour of gamma-hexachlorocyclohexane (gamma-HCH) in Europe, with emphasis on continental surface waters. The model is found to reasonably reproduce gamma-HCH distributions and variations along the years in atmosphere and soil; for continental surface waters, concentrations were reasonably well predicted for year 1995, when lindane was still used in agriculture, while for 2005, assuming severe restrictions in use, yields to substantial underestimation. Much better results were yielded when same mode of release as in 1995 was considered, supporting the conjecture that for gamma-HCH, emission data rather that model structure and parameterization can be responsible for wrong estimation of concentrations. Future research should be directed to improve the quality of emission data. Joint interpretation of monitoring and modelling results, highlights that lindane emissions in Europe, despite the marked decreasing trend, persist beyond the provisions of existing legislation. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Simultaneous determination of soil density and moisture by gamma ray attenuation from Cs137 and Am241

International Nuclear Information System (INIS)

Barros Ferraz, E.S. de.

1974-09-01

The method of simultaneous bulk density and soil moisture determination by attenuation of 241 Am and 137 Cs gamma-radiation is introduced and studied with details. Theoretical considerations are made about the attenuation process in the absorbers, the form of solving the problem of two unknowns; the sensitivity of the method; the influences of the resolution time of the electronic counting equipment, and of the compton scattering in the sample. From the methodological point of view studies are made about the influence of the geometry, adjustment of counting system, choice of radiation sources, attenuation coeficients and the manner of obtaining reliable measurements. It is also presented some applications of the method, its use in soil-water movement studies, in soil profile compaction studies, and specially in swelling soils

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

International Nuclear Information System (INIS)

Bunawas; Wahyudi; Syarbaini; Untara

2000-01-01

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

Assessment of ambient gamma dose rate around a prospective uranium mining area of South India - A comparative study of dose by direct methods and soil radioactivity measurements

Science.gov (United States)

Karunakara, N.; Yashodhara, I.; Sudeep Kumara, K.; Tripathi, R. M.; Menon, S. N.; Kadam, S.; Chougaonkar, M. P.

Indoor and outdoor gamma dose rates were evaluated around a prospective uranium mining region - Gogi, South India through (i) direct measurements using a GM based gamma dose survey meter, (ii) integrated measurement days using CaSO4:Dy based thermo luminescent dosimeters (TLDs), and (iii) analyses of 273 soil samples for 226Ra, 232Th, and 40K activity concentration using HPGe gamma spectrometry. The geometric mean values of indoor and outdoor gamma dose rates were 104 nGy h-1 and 97 nGy h-1, respectively with an indoor to outdoor dose ratio of 1.09. The gamma dose rates and activity concentrations of 226Ra, 232Th, and 40K varied significantly within a small area due to the highly localized mineralization of the elements. Correlation study showed that the dose estimated from the soil radioactivity is better correlated with that measured directly using the portable survey meter, when compared to that obtained from TLDs. This study showed that in a region having localized mineralization in situ measurements using dose survey meter provide better representative values of gamma dose rates.

Effect of soil moisture content on the radiosensitivity of soil bacteria and fungi

International Nuclear Information System (INIS)

Massoud, M.A.; El-Nennah, M.E.; El-Kholi, A.F.; Abd-Elmonem, M.A.

1982-01-01

The purpose of this investigation was to study the effect of soil moisture on the radiosensitivity of soil bacteria and fungi. The percentages of survival of soil bacteria and fungi, after exposure to different doses of gamma radiation, were lower in the moistened soil samples than in the dry one, inspite of the observed encouragement of wetting the soil samples, before gamma radiation exposure, on the proliferation of soil micro-organisms. This effect was explained by the indirect action from the breakdown products of radiolysis of water rather than by the direct damage to the cell structure

Gamma-ray and electrical resistivity measurements in soil with application of carbonatite and agricultural fertilizers in Distrito Federal

International Nuclear Information System (INIS)

Nascimento, Carlos Tadeu Carvalho do; Gaspar, Jose Carlos; Pires, Augusto Cesar Bittencourt; Ferreira, Francisco Jose Fonseca; Andrade, Leide Rovenia Miranda de

2008-01-01

EMBRAPA (Empresa Brasileira de Pesquisa Agropecuaria) and Brasilia University developed a research project about the viability of carbonatite rock as agricultural fertilizer. As an initial experiment, several mixtures of carbonatite, limestone, phosphorous and potassium compounds were added as fertilizers in an oxisol area (red-latosol, according with Brazilian System of Soil Classification), in Distrito Federal, central Brazil. The experiment area was divided in 56 plots (4 x 7m) and each plot received a fertilizer mixture. The purpose of this work was to verify if the addition of fertilizer mixture to the soil modified its radiometric and resistivity properties and if it is possible to identify this change. Gamma-ray and electrical resistivity measurements were obtained in an experimental area and in a natural savannah type vegetation area. The results showed that the fertilizer addition modified soil natural properties causing a small increase in K, U, Th levels and decreasing ten times electrical resistivity. A low contrast of radiation was observed between plots, and then it was not possible to differentiate the several treatments in base of gamma-ray measurements. Electrical resistivity was efficient to identify three groups of plots related to mixtures characteristics, respectively with phosphorous, potassium and limestone / carbonatite predominance. (author)

The measurement of moisture content and dry bulk-density of the top layer of agricultural soils, with minimum calibration, using a gamma-ray attenuation method

International Nuclear Information System (INIS)

Van der Westhuizen, M.; Van der Bank, D.J.; Meulke, M.

1978-06-01

Various methods of measuring moisture content and dry bulk-density of soil by means of gamma-ray attenuation are discussed. A new method is described in which the same parameters can be measured in consecutive determinations, but for which only one sample of unknown volume is needed for calibration. This method employs a radioactive source in a lead container in an aluminium tube in the soil. From the container the gamma rays follow a path at an angle upwards through the soil towards the detector. The method was tested in a number of experiments and the results are given in tables and graphs. The conclusion is that this method, which is fairly easy and quick to use, is accurate enough for most applications [af

Terrestrial gamma radioactivity levels and their corresponding external exposure of some soil samples from Elba protective area, Southeastern of Egypt

International Nuclear Information System (INIS)

El Arabi, A.M.; Ahmed, N.K.; Salahel Din, K.; Tykva, R.

2007-01-01

The study of natural gamma radioactivity was made to determine the concentrations of natural radionuclides in soil. Fifty four surface soil samples collected from three different cites (Wadi Daeeb , Wadi Sarara and Wadi Hodein) in Elba protective area, Southeastern of Egypt, were analyzed by Nal(Tl) detector to determine the activity concentrations of 226 Ra, 232 Th and 40 K. The mean activity concentration of radionuclides 226 Ra, 232 Th and 40 K are 20.9±1.6, 13.5 ± 1.1 and 477 ± 24 Bq kg -1 , respectively for Wadi Daeeb soils. The corresponding values for Wadi Sarara and Wadi Hodein soils are 27.8 ± 2.6, 17.8 ± 1.4 and 735.3 ± 29.8 Bq kg -1 and 20.3 ± 1.5, 12 ± 1 and 664.2 ± 20 Bq kg -1 , respectively. In order to evaluate the radiological hazard of the natural radioactivity, the radium equivalent activity (Ra eq ) and gamma activity concentration index (I) have been calculated and compared with the internationally approved values. The average annual effective doses outdoors, indoors and in total are estimated to be 0.046, 0.26 and 0.30 mSv, respectively for Wadi Daeeb soils. For Wadi Sarara and Wadi Hodein soils the corresponding values are 0.066, 0.37 and 0.44 mSv and 0.054, 0.30 and 0.36 mSv, respectively. Also the annual gonadal dose equivalent was calculated and found to be within safe limit

The use of gamma ray computed tomography to investigate soil compaction due to core sampling devices

International Nuclear Information System (INIS)

Pires, Luiz F.; Arthur, Robson C.J.; Correchel, Vladia; Bacchi, Osny O.S.; Reichardt, Klaus; Brasil, Rene P. Camponez do

2004-01-01

Compaction processes can influence soil physical properties such as soil density, porosity, pore size distribution, and processes like soil water and nutrient movements, root system distribution, and others. Soil porosity modification has important consequences like alterations in results of soil water retention curves. These alterations may cause differences in soil water storage calculations and matrix potential values, which are utilized in irrigation management systems. Because of this, soil-sampling techniques should avoid alterations of sample structure. In this work soil sample compaction caused by core sampling devices was investigated using the gamma ray computed tomography technique. A first generation tomograph with fixed source-detector arrangement and translation/rotational movements of the sample was utilized to obtain the images. The radioactive source is 241 Am, with an activity of 3.7 GBq, and the detector consists of a 3 in. x 3 in. NaI(Tl) scintillation crystal coupled to a photomultiplier tube. Soil samples were taken from an experimental field utilizing cylinders 4.0 cm high and 2.6 cm in diameter. Based on image analyses it was possible to detect compacted regions in all samples next to the cylinder wall due to the sampling system. Tomographic unit profiles of the sample permitted to identify higher values of soil density for deeper regions of the sample, and it was possible to determine the average densities and thickness of these layers. Tomographic analyses showed to be a very useful tool for soil compaction characterization and presented many advantages in relation to traditional methods. (author)

Natural radioactivity levels in soil samples around the flood affected salt field area, Kelambakkam, Chennai, Tamilnadu, India using gamma ray spectrometry

International Nuclear Information System (INIS)

Rajalakshmi, A.; Chandrasekaran, A.; Thangam, V.; Jananee, B.

2018-01-01

Humans are exposed to natural radiation from external sources, which include radionuclides in the earth and cosmic radiation. Gamma Ray spectroscopic technique was used to assess the natural radioactivity in soils around the flood affected salt field area, Kelambakkam Chennai, Tamilnadu, India. The activity concentration of 238 U, 232 Th, 40 K and absorbed dose rate of soil samples were calculated to assess the radiation hazards in the study area

Assessment of the equilibrium of Th-228 and Ra-228 by gamma-ray spectrometry in mangrove soils

International Nuclear Information System (INIS)

Paiva, Jose Daniel S.; Farias, Emerson E.G.; Franca, Elvis J. De

2015-01-01

The mangrove environment consists of soil containing high organic matter, characterized by the influence of continental and oceanic waters, relatively high concentrations of salts and exuberant vegetation. Mangroves also present high dynamics of chemical compound cycling, in which soils become quite relevant due to the influence of continental and oceanic sediments. Taking into account the different sources and transport of radionuclides within the mangrove environment, this study focused at the radioactive equilibrium of Thorium-232 series radionuclides, especially the Ra-228 and Thorium-228. For this, soil samples were collected in the crown projection of tree species from two mangroves located in the municipalities of Olinda/Recife and Rio Formoso, Pernambuco State, Brazil. The material was oven-dried and milled and test portions of 38 g were transferred to cylindrical vials and sealed. After 30 days, the natural radioactivity was measured during 80,000 seconds using High Resolution Gamma-Ray Spectrometry with a germanium detector of 2.2 keV of resolution at the 1,332 keV Co-60 photopeak. For Ra-228 determination, 911 keV gamma-ray line (Ac-228) were employed, while 238 keV (Pb-212) and 727 keV (Bi-212) were considered for estimating activity concentrations of Th-228. As a result, Ra-228 and Th 228 were in equilibrium since the activity concentrations (ranging from 35 Bq/kg to 50 Bq/kg) were not significantly different at the 95% confidence level. The results have confirmed that, even for environments of high dynamics such as mangroves, radioactive equilibrium of Th-228 and Ra-228 was kept, corroborating Th-232 determination in mangrove soils. (author)

Assessment of the equilibrium of Th-228 and Ra-228 by gamma-ray spectrometry in mangrove soils

Energy Technology Data Exchange (ETDEWEB)

Paiva, Jose Daniel S.; Farias, Emerson E.G.; Franca, Elvis J. De, E-mail: paivajds@gmail.com, E-mail: emersonemiliano@yahoo.com.br, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

2015-07-01

The mangrove environment consists of soil containing high organic matter, characterized by the influence of continental and oceanic waters, relatively high concentrations of salts and exuberant vegetation. Mangroves also present high dynamics of chemical compound cycling, in which soils become quite relevant due to the influence of continental and oceanic sediments. Taking into account the different sources and transport of radionuclides within the mangrove environment, this study focused at the radioactive equilibrium of Thorium-232 series radionuclides, especially the Ra-228 and Thorium-228. For this, soil samples were collected in the crown projection of tree species from two mangroves located in the municipalities of Olinda/Recife and Rio Formoso, Pernambuco State, Brazil. The material was oven-dried and milled and test portions of 38 g were transferred to cylindrical vials and sealed. After 30 days, the natural radioactivity was measured during 80,000 seconds using High Resolution Gamma-Ray Spectrometry with a germanium detector of 2.2 keV of resolution at the 1,332 keV Co-60 photopeak. For Ra-228 determination, 911 keV gamma-ray line (Ac-228) were employed, while 238 keV (Pb-212) and 727 keV (Bi-212) were considered for estimating activity concentrations of Th-228. As a result, Ra-228 and Th 228 were in equilibrium since the activity concentrations (ranging from 35 Bq/kg to 50 Bq/kg) were not significantly different at the 95% confidence level. The results have confirmed that, even for environments of high dynamics such as mangroves, radioactive equilibrium of Th-228 and Ra-228 was kept, corroborating Th-232 determination in mangrove soils. (author)

Gamma-ray attenuation to measure water contents and/or bulk densities of porous materials

International Nuclear Information System (INIS)

Ferraz, E.S.B.

1983-01-01

Attenuation of gamma radiation during transmission through soil and porous materials has been used for approximately three decades as a method for determining volumetric water content, theta, and bulk density, rho. This method is particularly suited for laboratory determinations of theta and rho in soil columns but it also has been used with success under field conditions. Measurements of attentuation of a collimated beam of monoernergetic gamma-rays has been used successfully by many investigators to provide rapid, non-destructive determinations for small volumes of soil. For stable soils, i.e. soils which do not swell upon wetting or shrink upon drying, rho may be assumed to remain constant during water flow through the soil, and thus changes in intensity or transmitted radiation may be attributed to changes in water content, theta. However, for unstable soils, the dry bulk density is subject to change with time during water flow through the soil and cannot be assumed to be a constant. Several investigators have utilized either a single beam of dual-energy gamma photons or two separate monoenergetic photon beams with greatly different energies to simultaneously determine theta and rho in these soils. A general review of gamma-ray attenuation methods for determining theta and rho in laboratory soil cores and in field soil profiles is reported in this paper. Theoretical equations for transmission and attenuation of gamma radiation in soils are presented for both single and double beams of gamma photons. Sensitivity, precision, accuracy, and experimental errors for the method are evaluated and discussed with respect to the theory. (author)

Feasibility study of photodiodes utilization in the soil-moisture determination by gamma transmission; Estudo da viabilidade da utilizacao de fotodiodos na determinacao de umidade de solos por transmissao gama

Energy Technology Data Exchange (ETDEWEB)

Santos, L A.P. dos

1992-08-01

This study was done to verify the viability of photodiodes, as gamma radiation detector ({sup 241} Am - Energy=60 KeV), to measure soil water content. The photodiodes used had different mechanical and electrical characteristics, and were tested on soils of different textures. A good linear correlation between the logarithm of the attenuation factor and soil-moisture demonstrated such viability, and that the low photopeak efficiency of these devices is not a limitation to the measurement of soil water content. Furthermore, the stability, the portability, and low cost of such semiconductor devices, including its electronic system, represent relevant characteristics that may justify the development of a reliable gamma meter system for field studies. (author). 37 refs, 21 figs, 20 tabs.

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.

Science.gov (United States)

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.

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

Science.gov (United States)

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

Gamma-ray measurements of natural radioactivity in cultivated and reclaimed soil, Upper Egypt

International Nuclear Information System (INIS)

Abbady, A.; El-Arabi, A.M.; Abbady, A.E.; Taha, S.

2007-01-01

Specific activity of primordial radionuclides in soil samples from 10 different locations in Qena governorate and wadi Elakita were determined by gamma-ray spectrometry. A total of 50 soil samples were collected from different sorts of soil with depth ranged from 0 - 25 cm . The energy peaks used were: 352.0 KeV of 214 Pb and 609.3, 1120.3 and 1764.5 KeV of 214 Bi for 226 Ra. In the case of 232 Th the energy peaks used were: 238.6 KeV of 212 Pb, 2615 of 208 Ti and 911.1 KeV of 228 Ac. While the radioactivity of 40 K was obtained from the single photopeak of this isotope at 1460.75 KeV. The total uncertainty of the obtained values of the radioactivity was calculated from the systematic and the random error of the measurements. Concentrations of radionuclides in soils analyzed in this study ranged from 7.5 to 85.5, 7.2 to 19.3 and 77.3 to 267.5 with mean values are 18.8 ± 3.4, 11.4 ± 3.4 and 150.8 ±12.3 (Bq.kg -1 ) for 226 Ra, 232 Th and 40 K ,respectively. The results obtained were compared with those from other studies in the world. The radiological health implication to the population that may result from these values is found to be very low and almost insignificant. No artificial radionuclide, however, was detected in any of the samples, hence, measurements have been taken as representing baseline values of these radionuclides in the soil in studying areas

Uranium, radium and thorium in soils with high-resolution gamma spectroscopy, MCNP-generated efficiencies, and VRF non-linear full-spectrum nuclide shape fitting

Directory of Open Access Journals (Sweden)

Metzger Robert

2017-01-01

Full Text Available A new method for analysis of uranium and radium in soils by gamma spectroscopy has been developed using VRF (“Visual RobFit” which, unlike traditional peak-search techniques, fits full-spectrum nuclide shapes with non-linear least-squares minimization of the chi-squared statistic. Gamma efficiency curves were developed for a 500 mL Marinelli beaker geometry as a function of soil density using MCNP. Collected spectra were then analyzed using the MCNP-generated efficiency curves and VRF to deconvolute the 90 keV peak complex of uranium and obtain 238U and 235U activities. 226Ra activity was determined either from the radon daughters if the equilibrium status is known, or directly from the deconvoluted 186 keV line. 228Ra values were determined from the 228Ac daughter activity. The method was validated by analysis of radium, thorium and uranium soil standards and by inter-comparison with other methods for radium in soils. The method allows for a rapid determination of whether a sample has been impacted by a man-made activity by comparison of the uranium and radium concentrations to those that would be expected from a natural equilibrium state.

Uranium, radium and thorium in soils with high-resolution gamma spectroscopy, MCNP-generated efficiencies, and VRF non-linear full-spectrum nuclide shape fitting

Science.gov (United States)

Metzger, Robert; Riper, Kenneth Van; Lasche, George

2017-09-01

A new method for analysis of uranium and radium in soils by gamma spectroscopy has been developed using VRF ("Visual RobFit") which, unlike traditional peak-search techniques, fits full-spectrum nuclide shapes with non-linear least-squares minimization of the chi-squared statistic. Gamma efficiency curves were developed for a 500 mL Marinelli beaker geometry as a function of soil density using MCNP. Collected spectra were then analyzed using the MCNP-generated efficiency curves and VRF to deconvolute the 90 keV peak complex of uranium and obtain 238U and 235U activities. 226Ra activity was determined either from the radon daughters if the equilibrium status is known, or directly from the deconvoluted 186 keV line. 228Ra values were determined from the 228Ac daughter activity. The method was validated by analysis of radium, thorium and uranium soil standards and by inter-comparison with other methods for radium in soils. The method allows for a rapid determination of whether a sample has been impacted by a man-made activity by comparison of the uranium and radium concentrations to those that would be expected from a natural equilibrium state.

Assessment of gamma radiation levels and natural radioactivity in soils along a subtropical river basin, China

Energy Technology Data Exchange (ETDEWEB)

Huang, Dekun; Yu, Tao [Third Institute of Oceanography, Xiamen (China). Lab. of Marine Isotopic Technology and Environmental Risk Assessment

2017-07-01

The activities of natural radionuclides in the environment can be used to assess radiological effects. Monitoring the radiation level in soils is important for public health. It also has important geochemical implications as most of the sediment eroded from river basins is from soil. Therefore, we carried out a soil sampling campaign along a subtropical river basin in southeastern China (Jiulong River). Surface and depth profile soils were collected, and the natural radionuclide activities were measured. The activities of the natural radionuclides {sup 238}U, {sup 232}Th, and {sup 40}K in the surface soils varied from 31.6 to 132.1 Bq kg-dry{sup -1}, 37.8 to 174.0 Bq kg-dry{sup -1}, and 52.3 to 596.2 Bq kg-dry{sup -1}, with average values of 56.7±30.3 Bq kg-dry{sup -1}, 86.7±41.3 Bq kg-dry{sup -1}, and 352.8±190.6 Bq kg-dry{sup -1}, respectively. The absorbed gamma dose in air and the annual effective dose equivalent (AEDE) in surface soils along the river basin were both higher than the world average. In the depth profiles, excess {sup 210}Pb ({sup 210}Pbex) decreased with depth and significant correlation between {sup 210}Pbex and TOC was observed, suggesting that they are affected by similar processes (leaching and sorption).

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

Energy Technology Data Exchange (ETDEWEB)

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

2003-07-01

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

Uranium in soil and gamma dose rate as proxies for the indoor radon risk: situation in Belgium

International Nuclear Information System (INIS)

Tondeur, F.; Cinelli, G.; Dehandschutter, B.

2017-01-01

Radon risk maps are usually based either on indoor radon data, or on measurements of soil gas radon and soil permeability. If these data are not available or not sufficient, it was suggested that other data could be used as an approximate substitute (a proxy) to the missing information, like the concentration of 238 U or 226 Ra in soils or the terrestrial gamma dose rate (TGDR). We examine here the correlation between airborne measurements of soil U and indoor radon, and between airborne U and TGDR, and their link with affected/unaffected areas. No clear correlation is found between airborne U and affected areas, as strongly affected areas are not characterised by a higher U level. Only the moderately affected area of Condroz can be connected to a higher U level, related to a few U anomalies. TGDR shows a rather good correlation with airborne U, but its relation with radon risk is less clear. Soil uranium and TGDR may help to screen out areas with very low U and very low TGDR, which have a low indoor radon risk, but they cannot be considered as good proxies for predicting radon-affected areas in Belgium. (authors)

Evaluation of an automated assay system to measure soil radionuclides by L x-ray and gamma-ray spectrometry

International Nuclear Information System (INIS)

Nyhan, J.W.; Drennon, B.J.; Crowell, J.M.

1982-08-01

An automated radionuclide assay system for conducting soil radioassays using L x-ray and gamma-ray spectrometry was evaluated. Wet chemistry assay procedures were shown to be considerably more time consuming than similar analyses of soil on this radionuclide assay system. The detection limits of 241 Am and plutonium were determined, as well as the reproducibility of radionuclide assay results. The L x-ray spectrometric measurements were compared with radiochemical analyses on several tuff samples. The assay system's intrinsic germanium detector was found to respond linearly to varying low concentrations of 241 Am and plutonium, both of which were easily detected in the presence of elevated concentrations of 137 Cs

Absorption of gamma-emitting fission products and activation products by rice under flooded and unflooded conditions from two tropical soils

International Nuclear Information System (INIS)

D'Souza, T.J.; Mistry, K.B.

1980-01-01

The absorption of gamma-emitting fission products 106 Ru, 125 Sb, 137 Cs and 144 Ce and activation products 59 Fe, 58 Co, 54 Mn and 65 Zn by rice plants grown on two contrasting tropical soils, namely, a blak soil (pellustert) and a laterite (oxisol), and the effects of flooding were studied under controlled conditions. Results indicated greater uptake of 106 Ru and 125 Sb from the black soil than from the laterite. In contrast, the uptake of 144 Ce and 137 Cs was greater in the laterite than in the black soil. Flooding treatment enhanced the uptake of all these fission products by rice plants in the laterite soil whereas this effect was observed only for 125 Sb and 137 Cs in the black soil. The plant uptake of activation products from the two soil types showed maximum accumulation of 65 Zn followed by 54 Mn, 59 Fe and 58 Co in both soil types. Besides, uptake of these nuclides was greater from the laterite soil than from the black soil. Flooding treatment for rice while showing a reduction of 59 Fe uptake showed an increase in plant uptake of 58 Co, 54 Mn and 65 Zn in both soil types. (orig.)

Laccase from a non-melanogenic, alkalotolerant gamma-proteobacterium JB isolated from industrial wastewater drained soil.

Science.gov (United States)

Bains, Jasleen; Capalash, Neena; Sharma, Prince

2003-07-01

A gram-negative, alkalotolerant bacterium, isolated from the soil continually drained with industrial wastewater and identified as gamma-proteobacterium by partial 16S rRNA sequence analysis, produced a polyphenol oxidase, which showed laccase but not tyrosinase activity. The organism grew well from pH 6 to 10 and produced laccase maximally at pH 10. The enzyme was stable from pH 3 to 10.6 for at least 24 h and was optimally active at 55 degrees C and pH 6.5 in a 5 min assay.

Dried gamma-irradiated sewage solids use on calcareous soils: crop yeilds and heavy metals uptake

International Nuclear Information System (INIS)

McCaslin, B.D.; Sivinski, J.S.

1979-01-01

Experiments designed to examine gamma-radiation effects on extractable and plant-available sludge elements and to examine the response of crops to sludge applications on two typical, calcareous soils in New Mexico are summarized. Information has been given indicating that the radiation process of reducing pathogens in sewage products being developed by Sandia Laboratories, does not significantly increase the chemical extractability and plant uptake of a broad range of nutrients and heavy metals. However, radiation treatment greatly facilitates handling sewage for experimentation, because pathogen contamination precautions are eliminated and weed seeds killed. Studies on the effects of sludge irradiation on plant nutrient uptake revealed no concentration increases, agreeing with results presented herein. Sewage products may have special potential for use on calcareous soils, such as in New Mexico. For instance, in New Mexico the lack of potassium in sewage products is not a problem and the naturally high pH of New Mexico soil greatly reduces plant availability of many problem heavy metals. Dramatic increases in yield are typified by the greenhouse and field results presented herein, especially for the known micronutrient deficient soils of New Mexico. Results indicate that sewage sludge is an excellent Zn and Fe fertilizer. More research needs to be done before the economics of sludge application can be calculated and more field information is needed before irradiated sewage products are used indiscriminately

Dried gamma-irradiated sewage solids use on calcareous soils: crop yeilds and heavy metals uptake

Energy Technology Data Exchange (ETDEWEB)

McCaslin, B.D.; Sivinski, J.S.

1979-01-01

Experiments designed to examine gamma-radiation effects on extractable and plant-available sludge elements and to examine the response of crops to sludge applications on two typical, calcareous soils in New Mexico are summarized. Information has been given indicating that the radiation process of reducing pathogens in sewage products being developed by Sandia Laboratories, does not significantly increase the chemical extractability and plant uptake of a broad range of nutrients and heavy metals. However, radiation treatment greatly facilitates handling sewage for experimentation, because pathogen contamination precautions are eliminated and weed seeds killed. Studies on the effects of sludge irradiation on plant nutrient uptake revealed no concentration increases, agreeing with results presented herein. Sewage products may have special potential for use on calcareous soils, such as in New Mexico. For instance, in New Mexico the lack of potassium in sewage products is not a problem and the naturally high pH of New Mexico soil greatly reduces plant availability of many problem heavy metals. Dramatic increases in yield are typified by the greenhouse and field results presented herein, especially for the known micronutrient deficient soils of New Mexico. Results indicate that sewage sludge is an excellent Zn and Fe fertilizer. More research needs to be done before the economics of sludge application can be calculated and more field information is needed before irradiated sewage products are used indiscriminately. (ERB)

Attenuation coefficients of soils

International Nuclear Information System (INIS)

Martini, E.; Naziry, M.J.

1989-01-01

As a prerequisite to the interpretation of gamma-spectrometric in situ measurements of activity concentrations of soil radionuclides the attenuation of 60 to 1332 keV gamma radiation by soil samples varying in water content and density has been investigated. A useful empirical equation could be set up to describe the dependence of the mass attenuation coefficient upon photon energy for soil with a mean water content of 10%, with the results comparing well with data in the literature. The mean density of soil in the GDR was estimated at 1.6 g/cm 3 . This value was used to derive the linear attenuation coefficients, their range of variation being 10%. 7 figs., 5 tabs. (author)

Detector calibration for in-situ gamma ray spectrometry

CERN Document Server

Balea, G

2002-01-01

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

Absorption of gamma-emitting fission products and activation products by rice under flooded and unflooded conditions from two tropical soils

Energy Technology Data Exchange (ETDEWEB)

D' Souza, T J; Mistry, K B [Bhabha Atomic Research Centre, Bombay (India). Biology and Agriculture Div.

1980-01-01

The absorption of gamma-emitting fission products /sup 106/Ru, /sup 125/Sb, /sup 137/Cs and /sup 144/Ce and activation products /sup 59/Fe, /sup 58/Co, /sup 54/Mn and /sup 65/Zn by rice plants grown on two contrasting tropical soils, namely, a blak soil (pellustert) and a laterite (oxisol), and the effects of flooding were studied under controlled conditions. Results indicated greater uptake of /sup 106/Ru and /sup 125/Sb from the black soil than from the laterite. In contrast, the uptake of /sup 144/Ce and /sup 137/Cs was greater in the laterite than in the black soil. Flooding treatment enhanced the uptake of all these fission products by rice plants in the laterite soil whereas this effect was observed only for /sup 125/Sb and /sup 137/Cs in the black soil. The plant uptake of activation products from the two soil types showed maximum accumulation of /sup 65/Zn followed by /sup 54/Mn, /sup 59/Fe and /sup 58/Co in both soil types. Besides, uptake of these nuclides was greater from the laterite soil than from the black soil. Flooding treatment for rice while showing a reduction of /sup 59/Fe uptake showed an increase in plant uptake of /sup 58/Co, /sup 54/Mn and /sup 65/Zn in both soil types.

Towards a methodology for removing and reconstructing soil protists with intact soil microbial communities

Science.gov (United States)

Hu, Junwei; Tsegaye Gebremikael, Mesfin; Salehi Hosseini, Pezhman; De Neve, Stefaan

2017-04-01

Soil ecological theories on the role of soil fauna groups in soil functions are often tested in highly artificial conditions, i.e. on completely sterilized soils or pure quartz sand re-inoculated with a small selection of these fauna groups. Due to the variable sensitivity of different soil biota groups to gamma irradiation, the precise doses that can be administered, and the relatively small disturbance of soil physical and chemical properties (relative to e.g. autoclaving, freezing-thawing and chemical agents), gamma irradiation has been employed to selectively eliminate soil organisms. In recent research we managed to realistically estimate on the contribution of the entire nematode communities to C and N mineralization in soil, by selective removal of nematodes at 5 kGy gamma irradiation doses followed by reinoculation. However, we did not assess the population dynamics of protozoa in response to this irradiation, i.e. we could not assess the potential contribution of protists to the mineralization process. Selective removal of protists from soils with minimal disturbance of the soil microflora has never been attempted and constitutes a highly challenging but potentially groundbreaking technique in soil ecology. Accordingly, the objective of this research is to modify the successful methodology of selective elimination of nematodes, to selectively eliminate soil fauna including nematodes and protists with minimal effects on the soil microbial community and reconstruct soil protists and microbial communities in completely sterilized soil. To this end, we here compared two different approaches: 1) remove nematodes and protists while keeping the microbial community intact (through optimizing gamma irradiation doses); 2) reconstruct protists and microbial communities in sterilized soil (through adding multicellular fauna free pulverized soil). The experiment consists of 7 treatments with soil collected from 0 to 15 cm layer of an organically managed agricultural

Detailed deposition density maps constructed by large-scale soil sampling for gamma-ray emitting radioactive nuclides from the Fukushima Dai-ichi Nuclear Power Plant accident.

Science.gov (United States)

Saito, Kimiaki; Tanihata, Isao; Fujiwara, Mamoru; Saito, Takashi; Shimoura, Susumu; Otsuka, Takaharu; Onda, Yuichi; Hoshi, Masaharu; Ikeuchi, Yoshihiro; Takahashi, Fumiaki; Kinouchi, Nobuyuki; Saegusa, Jun; Seki, Akiyuki; Takemiya, Hiroshi; Shibata, Tokushi

2015-01-01

Soil deposition density maps of gamma-ray emitting radioactive nuclides from the Fukushima Dai-ichi Nuclear Power Plant (NPP) accident were constructed on the basis of results from large-scale soil sampling. In total 10,915 soil samples were collected at 2168 locations. Gamma rays emitted from the samples were measured by Ge detectors and analyzed using a reliable unified method. The determined radioactivity was corrected to that of June 14, 2011 by considering the intrinsic decay constant of each nuclide. Finally the deposition maps were created for (134)Cs, (137)Cs, (131)I, (129m)Te and (110m)Ag. The radioactivity ratio of (134)Cs-(137)Cs was almost constant at 0.91 regardless of the locations of soil sampling. The radioactivity ratios of (131)I and (129m)Te-(137)Cs were relatively high in the regions south of the Fukushima NPP site. Effective doses for 50 y after the accident were evaluated for external and inhalation exposures due to the observed radioactive nuclides. The radiation doses from radioactive cesium were found to be much higher than those from the other radioactive nuclides. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Gamma radiometric survey of Jamaica

International Nuclear Information System (INIS)

Lalor, G.C.; Robotham, H.; Miller, J.M.; Simpson, P.R.

1989-01-01

The results of a total gamma radiometric survey of Jamaica, carried out with car-borne instrumentation, are presented and the data compared with the contents of potassium, thorium and uranium in rocks and in surface (soil, stream-sediment, pan concentrate and water) samples obtained at six sites selected to be representative of the principal rock types and surface environments of Jamaica. The work formed part of an orientation study for a regional geochemical survey of the CARICOM countries of the Caribbean. The initial results indicate that enhanced gamma activity is correlated with enrichment in uranium and thorium, but not potassium, in terra rossa soils and/or bauxite deposits in limestone. Elsewhere, gamma levels are increased on the Above Rocks Cretaceous basement Inlier, where they correlate generally with the presence of volcanogenic sediments and a granodiorite intrusion. The lowest radioactivity was recorded in the vicinity of ultrabasic rocks in the Blue Mountains Inlier. (author)

Calibration of a Gamma Spectrometry System Used for the Determination of Cs-137 in Spanish Soils

International Nuclear Information System (INIS)

Barreraa, M.; Romero, M. L.; Valino, F.

2008-01-01

The document describes the methodology used at CIEMAT in order to determine, by gamma spectrometry, the background levels of the radionuclide Cs-137 in soils of the Spanish peninsular territory. the work is a part of an extensive research project developed jointly by the University of the Basque Country (UPV-EHU) and the CIEMAT, endellite Content and migration of radiocaesium and radiostrontium in Spanish soils, which is funded by the Plan I+D of the Spanish Nuclear Security Council (CSN). The objective of the project is to establish the reference levels of man-made radionuclides in Spanish soils, with respect to which the evaluation of a possible posterior accidental release of radioactive material could be appraised. The activity concentration of the fission products Cs-137 has been determined in 34 soil cores extracted from representative Spanish soils type zones. This publication describes the experimental system employed, its calibration, the particular conditions applied to perform the measurements, as well as the experimental validation of the methodology. The activity profiles and inventories of the radioactive element so obtained are also presented. The estimation of the background Cs-137 reference levels, will provide a basis for later applications as the study of the spatial distribution in the region, the determination of the correlation between the deposited activity and the meteorological conditions, or the calculation of the specific migration parameters of the radioactive elements in Mediterranean conditions. (Author) 15 refs

Validation of 226Ra, 228Ra and 210Pb measurements in soil and sediment samples through high resolution gamma ray spectrometry

International Nuclear Information System (INIS)

Dias, Danila Carrijo da Silva; Silva, Nivaldo Carlos da; Bonifacio, Rodrigo Leandro; Guerrero, Eder Tadeu Zenun

2013-01-01

Radionuclides found in ore extraction waste materials are a great source of concern regarding public health and environmental safety. One technique to determine the concentration of substances is high resolution gamma ray spectrometry using HPGe. Validating a measurement technique is essential to warrant high levels of quality to any scientific work. The Laboratory of Pocos de Caldas of the Brazilian Commission for Nuclear Energy partakes into a Quality Management System project, seeking Accreditation under ISO/IEC 17025 through the validation of techniques of chemical and radiometric analysis of environmental samples from water, soil and sediment. The focus of the Radon Laboratory at LAPOC is validation of Ra-226, Ra-228 and Pb-210 concentration determinations in soil and sediment through a gamma spectrometer system. The stages of this validation process included sample reception and preparation, detector calibration and sample analyses. Dried samples were sealed in metallic containers and analyzed after radioactive equilibrium between Ra-226 and daughters Pb-214 and Bi-214. Gamma spectrometry was performed using CANBERRA HPGe detector and gamma spectrum software Genie 2000. The photo peaks used for Ra-226 determination were 609 keV and 1020 keV of Bi-214 and 351 keV of Pb-214. For the Ra-228 determination a photopeak of 911 keV was used from its short half-life daughter Ac-228 (T1/2 = 6.12 h). For Pb-210, the photopeak of 46.5 keV was used, which, due to the low energy, self-absorption correction was needed. Parameters such as precision, bias/accuracy, linearity, detection limit and uncertainty were evaluated for that purpose. The results have pointed to satisfying results. (author)

Physiological response of lovage (levisticum officinale, koch) plant to gamma radiation and organic fertilizers

International Nuclear Information System (INIS)

Taha, A.T.A.

2009-01-01

The main objective of this work is to study physiological response of lovage plant to gamma radiation and organic fertilizers.Two field experiments were conduct under conditions of newly reclaimed soil (sandy loam soil) during two successive seasons (2003/2004 and 2004/2005) in experimental farm , NRC,AEA Inshas. lovage fruits were irradiated before sowing with gamma rays at 0,20,40,60 and 80 Gy. Before planting farm yard manure (FYM) at rates of 0,20,30 and 40 m 3 /fed. Was applied to soil in combination with gamma doses in the first experiment, in the second one, chicken manure at 0,10,15 and 20 m 3 /fed. was added to soil before planting in combination with the same used gamma doses in first experiment. Growth of lovage plants was considerably stimulated by irradiating fruits before sowing with low gamma doses, in particularly at 60 Gy, which greatly increased plant height, number of branches/plant, stem thickness and dry matter yield of shoots. Similar trend was also observed with leaf chlorophyll content which increased due to low gamma doses . Low gamma doses markedly encouraged nutrients uptake by lovage plants which increased levels and total contents of N, P, K, Fe,Zn and Mn in plant shoots. Fruits yield, volatile oil % and oil yield and fruits index value were increased by low gamma doses particularly at 60 Gy.

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

Directory of Open Access Journals (Sweden)

Todorovik Aleksandra

2012-01-01

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

Introduction to nuclear techniques in agronomy and plant biology

International Nuclear Information System (INIS)

Vose, P.B.

1980-01-01

The subject is covered in chapters, entitled: nature of isotopes and radiation; nuclear reactions; working with radioisotopes; detection systems and instrumentation; radioassay; radioisotopes and tracer principles; stable isotopes as tracers - mainly the use of 15 N; activation analysis for biological samples; x-ray fluorescence spectrography for plants and soils; autoradiography; isotopes in soils studies; isotopic tracers in field experimentation; nuclear techniques in plant science; nuclear techniques for soil water; radiation and other induced mutation in plant breeding. (author)

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

Science.gov (United States)

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

2017-12-01

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

Investigation of zones with increased ground surface gamma radiation

International Nuclear Information System (INIS)

Butkus, D.V.; Morkunas, G.S.; Styro, B.I.

1989-01-01

Measurements of the increased gamma radiation zones of soils were conducted in the South-Western part of the Litvinian. The shores of lakes in the north-eastern part of the Suduva high land were investigated. the maximum values of the gamma radiation dose rates were distributed along the lake shores at a distance of 1 m from the water surface, while farther than 1.5 m from it the dose rate was close to the natural value. The increased gamma radiation intensity zones on the ground surface were found only at the northern (Lake Reketija) or the western shore (other lakes under investigation). The highest values of the gamma radiation dose 200-600 μR/h (0.5-1.5 nGy/s) were observed in the comparatively small areas (up to several square metres). The gamma radiation intensity of soil surface increased strongly moving towards the point where the maximum intensity was obsered. 10 figs

Pesticide-soil microflora interactions in flooded rice soils

International Nuclear Information System (INIS)

Sethunathan, N.; Siddaramappa, R.; Siddarame Gowda, T.K.; Rajaram, K.P.; Barik, S.; Rao, V.R.

1976-01-01

Isotope studies revealed that gamma and beta isomers of HCH (hexachlorocyclohexane) decomposed rapidly in nonsterile soils capable of attaining redox potentials of -40 to -100mV within 20 days after flooding. Degradation was slow, however, in soils low in organic matter and in soils with extremely low pH and positive potentials, even after several weeks of flooding. Under flooded conditions, endrin decomposed to six metabolites in most soils. There is evidence that biological hydrolysis of parathion is more widespread than hitherto believed, particularly under flooded soil conditions. Applications of benomyl (fungicide) to a simulated-oxidized zone of flooded soils favoured heterotrophic nitrification. (author)

Aspects of land application of sewage solids and gamma-irradiated dried sewage solids on calcareous soils

International Nuclear Information System (INIS)

McCaslin, B.D.; O'Connor, G.A.; Sivinski, J.S.

1980-01-01

One of the cheapest and generally most convenient methods of disposing of sewage sludge is by land application. The greatest risks of land application are potential contamination of the environment by heavy metals, other toxicants, and pathogens. Irradiation of sewage sludge has been shown to have little or no effect on sludge elements available to plants, and can remove the potential pathogen problem. Work at New Mexico State University has shown that, with little risk, gamma-irradiated sewage sludge can be used to great advantage for crop production, especially on highly calcareous soils low in heavy metals essential for plant growth

Determination of density and volumetric water content of soil at multiple photon energies

Energy Technology Data Exchange (ETDEWEB)

Un, A., E-mail: ademun25@yahoo.co [Department of Physics, Faculty of Science and Arts, Agri Ibrahim Cecen University, 04100 Agri (Turkey); Demir, D.; Sahin, Y. [Department of Physics, Faculty of Science, Atatuerk University, 25240 Erzurum (Turkey)

2011-08-15

Gamma ray transmission methods have been used accurately for the study of the properties of soil for agricultural purposes. In this study, density and volumetric water content of soil are determined by using gamma ray transmission method. To this end, the soil sample was collected from Erzurum, Turkey. The attenuation of strongly collimated monoenergetic gamma beam through the soil sample was measured using a 3x3x1 mm{sup 3} cadmium telluride (CdTe) detector. The radioactive sources used in the experiment were {sup 241}Am, {sup 133}Ba and {sup 137}Cs. The mass attenuation coefficients of dry soil sample were calculated from the transmission measurements. It was observed that gamma ray transmission method in measurement of the soil parameters with the portable CdTe detector has advantages such as practical, inexpensive, non-destructive and fast analysis.

Determination of density and volumetric water content of soil at multiple photon energies

International Nuclear Information System (INIS)

Un, A.; Demir, D.; Sahin, Y.

2011-01-01

Gamma ray transmission methods have been used accurately for the study of the properties of soil for agricultural purposes. In this study, density and volumetric water content of soil are determined by using gamma ray transmission method. To this end, the soil sample was collected from Erzurum, Turkey. The attenuation of strongly collimated monoenergetic gamma beam through the soil sample was measured using a 3x3x1 mm 3 cadmium telluride (CdTe) detector. The radioactive sources used in the experiment were 241 Am, 133 Ba and 137 Cs. The mass attenuation coefficients of dry soil sample were calculated from the transmission measurements. It was observed that gamma ray transmission method in measurement of the soil parameters with the portable CdTe detector has advantages such as practical, inexpensive, non-destructive and fast analysis.

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

International Nuclear Information System (INIS)

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

2016-01-01

With interest in establishing baseline concentrations of 137 Cs 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. - Highlights: • A baseline for the radionuclide 137 Cs in soil samples collected from Qatar was established. • 129 soil samples collected across the landscape. • Samples were collected before the most recent accident “the 2011 Fukushima Dai-ichi NNP accident”. • The highest activity concentration was found to be 15.41±0.67 Stat. and 0.11 Syst. • The relatively high concentrations can be attributed to rain washout.

Factors influencing in situ gamma-ray measurements

Science.gov (United States)

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

2009-04-01

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

Different bacterial communities in heat and gamma irradiation treated replant disease soils revealed by 16S rRNA gene analysis – contribution to improved aboveground apple plant growth?

Directory of Open Access Journals (Sweden)

Bunlong eYim

2015-11-01

Full Text Available Replant disease (RD severely affects apple production in propagation tree nurseries and in fruit orchards worldwide. This study aimed to investigate the effects of soil disinfection treatments on plant growth and health in a biotest in two different RD soil types under greenhouse conditions and to link the plant growth status with the bacterial community composition at the time of plant sampling. In the biotest performed we observed that the aboveground growth of apple rootstock M26 plants after eight weeks was improved in the two RD soils either treated at 50 °C or with gamma irradiation compared to the untreated RD soils. Total community DNA was extracted from soil loosely adhering to the roots and quantitative real-time PCR revealed no pronounced differences in 16S rRNA gene copy numbers. 16S rRNA gene-based bacterial community analysis by denaturing gradient gel electrophoresis (DGGE and 454-pyrosequencing revealed significant differences in the bacterial community composition even after eight weeks of plant growth. In both soils, the treatments affected different phyla but only the relative abundance of Acidobacteria was reduced by both treatments. The genera Streptomyces, Bacillus, Paenibacillus and Sphingomonas had a higher relative abundance in both heat treated soils, whereas the relative abundance of Mucilaginibacter, Devosia and Rhodanobacter was increased in the gamma-irradiated soils and only the genus Phenylobacterium was increased in both treatments. The increased abundance of genera with potentially beneficial bacteria, i.e. potential degraders of phenolic compounds might have contributed to the improved plant growth in both treatments.

Effect of gamma irradaition on growth and nutrients uptake of sorghum plants

International Nuclear Information System (INIS)

Eleiwa, M.E.; Rabie, M.H.

1994-01-01

A pot experiment was carried out using sandy calcareous soils to study the effects of gamma irradiating doses for sorghum seeds on dry matter yield and elemental uptake. Three cuttings were taken during the experiment every 40 days. Results showed that 4 Kr. dose was the best dose that caused significant higher increase of dry matter yield and nutrients uptake for three cuttings under both types of soil. Gamma irradiation doses at 8 Kr. and above all had an adverse affect on dry matter yield and nutrients uptake, especially under calcareous soil. (author)

Use of gamma surveys from the aircraft for hydrological forecasts on the area with irregular snow pack

Energy Technology Data Exchange (ETDEWEB)

Vershinina, L K

1979-01-01

Gamma snow surveys from the aircraft based on the measurements of the attenuation of gamma-radiation of soils by the snow pack are discussed. Radiation rate depends on the amount of water on the soil surface and in the top layer 30 to 40 cm deep. Therefore, if measurements are made twice (without snow and with snow pack available) water equivalent of snow cover may be determined only when soil moisture content changes do not occur during the period between the dates of gamma surveys. In the areas with frequent winter thaws, standard land snow surveys do not provide snow storage evaluation with the accuracy sufficient for spring flow prediction. It is shown that when gamma-radiation of absolutely dry soils determined at the laboratory is known as well as of naturally moistened soils during the periods of gamma surveys of the snow pack from the aircraft, and when data is available on soil moisture content obtained from the measurements at the base land network, then a reliable estimation of snow storage on the watershed surfaces in the regions with irregular snow cover is quite possible. This ensures a significant accuracy increase of spring snow melt flood forecasting, particularly concerning winters with little snow.

Use of gamma surveys from the airraft for hydrological forecasts on the area with irregular snow pack

Energy Technology Data Exchange (ETDEWEB)

Vershinina, L K [State Hydrological Institute, Leningrad (USSR)

1979-01-01

Gamma snow surveys from aircraft based on the measurement of the attenuation of gamma-radiation of soils by the snow pack are discussed. Radiation rate depends on the amount of water on the soil surface and in the top layer 30 to 40 cm deep. Therefore, if measurements are made twice (without snow and with snow pack available) the water equivalent of the snow cover may be determined only in cases when soil moisture content changes do not occur during the period between the dates of gamma surveys. In areas with frequent winter thaws standard land snow surveys do not provide snow storage evaluation with accuracy sufficient for spring flow prediction. It is shown that when gamma-radiation of absolutely dry soils determined at the laboratory is known, as well as of naturally moistened soils during the periods of gamma surveys of the snow pack from aircraft, and when data is available on soil moisture content obtained from measurements at the base land network, then a reliable estimation of snow storage on the watershed surfaces in regions with irregular snow cover is quite possible. This ensures a significant accuracy increase in spring snow melt flood forecasting, in particular during winters with little snow.

Population doses from terrestrial gamma exposure in China

International Nuclear Information System (INIS)

Ren, T.; Wang, Z.; Zhu, C.

1993-01-01

In order to estimate terrestrial gamma radiation exposures, three nationwide surveys have been completed since 1981. The population weighted outdoor and indoor arithmetic means of gamma dose rates based on momentary measurements using a NaI(T1) environmental radiation meter and a high pressured ionization chamber are 80.3 and 120 nGy.h -1 . The means based on integrating measurements using TLD natural radionuclides concentrations in soil, determined by gamma spectrometry analyses, are 72.8 and 102 nGy.h -1 , respectively. These surveys were conducted independently and equally representative. The best estimation of site-averaged and population weighted gamma dose rates in China, based on all these surveys, would be 70 and 98 nGy.h -1 for indoor and outdoor, respectively. The annual average of effective dose equivalent is 0.56 mSv. These values are higher than the world averages estimated by UNSCEAR. The main reason is that the concentrations of 232 Th and 40 K in soil of China are much higher than the world average estimated. (author). 4 refs, 2 tabs

Simultaneous measurements of global vibrational spectra and dephasing times of molecular vibrational modes by broadband time-resolved coherent anti-Stokes Raman scattering spectrography

International Nuclear Information System (INIS)

Yin Jun; Yu Ling-Yao; Liu Xing; Wan Hui; Lin Zi-Yang; Niu Han-Ben

2011-01-01

In broadband coherent anti-Stokes Raman scattering (CARS) spectroscopy with supercontinuum (SC), the simultaneously detectable spectral coverage is limited by the spectral continuity and the simultaneity of various spectral components of SC in an enough bandwidth. By numerical simulations, the optimal experimental conditions for improving the SC are obtained. The broadband time-resolved CARS spectrography based on the SC with required temporal and spectral distributions is realised. The global molecular vibrational spectrum with well suppressed nonresonant background noise can be obtained in a single measurement. At the same time, the measurements of dephasing times of various molecular vibrational modes can be conveniently achieved from intensities of a sequence of time-resolved CARS signals. It will be more helpful to provide a complete picture of molecular vibrations, and to exhibit a potential to understand not only both the solvent dynamics and the solute-solvent interactions, but also the mechanisms of chemical reactions in the fields of biology, chemistry and material science. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

Soil water management

International Nuclear Information System (INIS)

Nielsen, D.R.; Cassel, D.K.

1984-01-01

The use of radiation and tracer techniques in investigations into soil water management in agriculture, hydrology etc. is described. These techniques include 1) neutron moisture gauges to monitor soil water content and soil water properties, 2) gamma radiation attenuation for measuring the total density of soil and soil water content, 3) beta radiation attenuation for measuring changes in the water status of crop plants and 4) radioactive and stable tracers for identifying pathways, reactions and retention times of the constituents in soils and groundwater aquifers. The number and spacing of soil observations that should be taken to represent the management unit are also considered. (U.K.)

Determination of radionuclides and elemental composition of clay soils by gamma and X-ray spectrometry

International Nuclear Information System (INIS)

Isinkaye, O. M.; Shitta, O. M. B.; Oderinde, O. M.

2011-01-01

Radiochemical and elemental analysis of clay soils collected from different locations within Ekiti State have been performed in this study using gamma and XRF spectrometric measurements. The results of this study show that the mean concentration of 238 U ranged from 2.2±1.0ppm to 3.2±1.1ppm, 232 Th ranged from 4.0±0.5ppm to 5.7±1.7ppm, while 40 K presented in percent by weight ranged from 0.4±0.2 to 1.3±0.3. The XRF analysis revealed 4 major elements and 11 minor or trace elements present in the clay samples. The distribution of the various major and trace elements in all the sampling sites do not follow any systematic trend but vary from point to point. To assess the level of contamination and the possible anthropogenic impact in the clay soils, the enrichment factor (EF) and the geoaccumulation index (Igeo) were estimated for some potential hazardous elements. The results indicate that Cu, Zn, Ni and Mn have EF<2 indicating minimal or no enrichment while Pb is moderately enriched in all the locations.

Validation of {sup 226}Ra, {sup 228}Ra and {sup 210}Pb measurements in soil and sediment samples through high resolution gamma ray spectrometry

Energy Technology Data Exchange (ETDEWEB)

Dias, Danila Carrijo da Silva; Silva, Nivaldo Carlos da; Bonifacio, Rodrigo Leandro; Guerrero, Eder Tadeu Zenun [Comissao Nacional de Energia Nuclear (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas

2013-07-01

Radionuclides found in ore extraction waste materials are a great source of concern regarding public health and environmental safety. One technique to determine the concentration of substances is high resolution gamma ray spectrometry using HPGe. Validating a measurement technique is essential to warrant high levels of quality to any scientific work. The Laboratory of Pocos de Caldas of the Brazilian Commission for Nuclear Energy partakes into a Quality Management System project, seeking Accreditation under ISO/IEC 17025 through the validation of techniques of chemical and radiometric analysis of environmental samples from water, soil and sediment. The focus of the Radon Laboratory at LAPOC is validation of Ra-226, Ra-228 and Pb-210 concentration determinations in soil and sediment through a gamma spectrometer system. The stages of this validation process included sample reception and preparation, detector calibration and sample analyses. Dried samples were sealed in metallic containers and analyzed after radioactive equilibrium between Ra-226 and daughters Pb-214 and Bi-214. Gamma spectrometry was performed using CANBERRA HPGe detector and gamma spectrum software Genie 2000. The photo peaks used for Ra-226 determination were 609 keV and 1020 keV of Bi-214 and 351 keV of Pb-214. For the Ra-228 determination a photopeak of 911 keV was used from its short half-life daughter Ac-228 (T1/2 = 6.12 h). For Pb-210, the photopeak of 46.5 keV was used, which, due to the low energy, self-absorption correction was needed. Parameters such as precision, bias/accuracy, linearity, detection limit and uncertainty were evaluated for that purpose. The results have pointed to satisfying results. (author)

Gamma-ray spectrometry applied to agricultural soil in the northwest of the State of Rio de Janeiro; Gamaespectrometria aplicada em solo agricola no noroeste do Estado do Rio de Janeiro

Energy Technology Data Exchange (ETDEWEB)

Santos, Andrea Cristina Lima dos; Nascimento, Carlos Tadeu Carvalho do [Instituto de Geociencias, Universidade de Brasilia, DF (Brazil); Menezes, Paulo de Tarso Luiz, E-mail: andrealima@unb.br, E-mail: carlostadeu@unb.br, E-mail: ptarsomenezes@pq.cnpq.br [Faculdade de Geologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ (Brazil)

2008-04-15

The present work presents the use of gamma-ray spectrometry applied to precision agriculture in a sub-tropical area. Our dataset comprises measurements both in rock and residual soil. The soil dataset shows a reduction of 20% on U and Th and 10% on K, when compared to rock samples. This difference could be related to K supplementation associated to chemical fertilization. (author)

Potential of recycling gamma-irradiated sewage sludge for use as a fertilizer: a study on chickpea (Cicer arietinum)

International Nuclear Information System (INIS)

Pandya, G.A.; Sachidanand, S.; Modi, V.V.

1989-01-01

The effects of gamma-irradiated sludge on the growth and yield of chickpea (Cicer arietinum) in pot cultures have been studied. Compared to plants grown only in soil, root length, fresh weight and dry weight of plants grown in soil supplemented with unirradiated sludge were found to be significantly reduced. This inhibition in growth was found to be nullified when plants were grown in soil supplemented with gamma-irradiated sludge, suggesting that gamma radiation induced inactivation of toxic substance(s) in sludge. The protein content of plants grown in soil supplemented with irradiated sludge was also found to be significantly increased compared to those grown with unirradiated or no sludge, after 45 days. There was no significant effect of gamma irradiated sludge on shoot length, total soluble sugars, starch content and yield of chickpea plants. The results obtained suggest that the sludge tested, and obtained from the digester of a conventional domestic sewage treatment plant, is inhibitory to several growth parameters. Gamma irradiation of sewage resulted in removal of this inhibition. This suggests a possibility of beneficial and safe recycling of gamma-irradiated sludge for agricultural uses. (author)

Application of neutron-gamma analysis for determination of C/N ratio in compost

Science.gov (United States)

Neutron-gamma analysis is based on the acquisition of gamma rays from neutron irradiated study objects. The intensity and energy of the registered gamma rays gives information on the types and amounts of elements in the studied object. The use of this method for measurements of soil carbon demonstra...

Indoor radon in a Spanish region with different gamma exposure levels

International Nuclear Information System (INIS)

Quindos, L.S.; Fernandez, P.L.; Sainz, C.; Fuente, I.; Nicolas, J.; Quindos, L.; Arteche, J.

2008-01-01

In the beginning of 1990s within the framework of a national radon survey of more than 1500 points, radon measurements were performed in more than 100 houses located in Galicia region, in the Northwest area of Spain. The houses were randomly selected only bearing in mind general geological aspects of the region. Subsequently, a nationwide project called MARNA dealt with external gamma radiation measurements in order to draw a Spanish natural radiation map. The comparison in Galicia between these estimations and the indoor radon levels previously obtained showed good agreement. With the purpose of getting a confirmation of this relationship and also of creating a radon map of the zone, a new set of measurements were carried out in 2005. A total of 300 external gamma radiation measurements were carried out as well as 300 measurements of 226 Ra, 232 Th and 40 K content in soil. Concerning radon, 300 1-m-depth radon measurements in soil were performed, and indoor radon concentration was determined in a total of 600 dwellings. Radon content in soil gave more accurate indoor radon predictions than external gamma radiation or 226 Ra concentration in soil

Study of gamma irradiation effects on the etching and optical properties of CR-39 solid state nuclear track detector and its application to uranium assay in soil samples

International Nuclear Information System (INIS)

Amol Mhatre; Kalsi, P.C.

2011-01-01

The gamma irradiation effects in the dose range of 2.5-43.0 Mrad on the etching and optical characteristics of CR-39 solid state nuclear track detector (SSNTD) have been studied by using etching and UV-Visible spectroscopic techniques. From the measured bulk etch rates at different temperatures, the activation energies for bulk etching at different doses have also been determined. It is seen that the bulk etch rates increase and the activation energies for bulk etching decrease with the increase in gamma dose. The optical band gaps of the unirradiated and the gamma -irradiated detectors determined from the UV-Visible spectra were found to decrease with the increase in gamma dose. These results have been explained on the basis of scission of the detector due to gamma irradiation. The present studies can be used for the estimation of gamma dose in the range of 2.5-43.0 Mrad and can also be used for estimating track registration efficiency in the presence of gamma dose. The CR-39 detector has also been applied for the assay of uranium in some soil samples of Jammu city. (author)

A computer program integrating a multichannel analyzer with gamma analysis for the estimation of 226 Ra concentration in soil samples

International Nuclear Information System (INIS)

Wilson, J. E.

1992-08-01

A new hardware/software system has been implemented using the existing three-regions-of-interest method for determining the concentration of 226 Ra in soil samples for the Pollutant Assessment Group of the Oak Ridge National Laboratory. Consisting of a personal computer containing a multichannel analyzer, the system utilizes a new program combining the multichannel analyzer with a program analyzing gamma-radiation spectra for 226 Ra concentrations. This program uses a menu interface to minimize and simplify the tasks of system operation

HT oxidation activity of soil irradiated with gamma radiation

International Nuclear Information System (INIS)

Momoshima, Noriyuki; Tjahaja, P.I.; Takashima, Yoshimasa

1992-01-01

The HT oxidation activity was examined for soils irradiated with 60 Co γ-rays at various doses. The HT oxidation rate decreased with increase of initial H 2 concentration, indicating a similar oxidation mechanism between HT and H 2 . Irradiated soils showed decrease of oxidation activity with dose suggests that HT and H 2 oxidation activities were affected by sterilization with γ-rays. The decline of the oxidation activity with dose was analyzed by a composite of two components with different radiosensitivity and they were considered to be activities of soil microorganisms and abiotic soil enzymes. The oxidation activity due to soil microorganisms would be important at low dose range and more radioresistant abiotic soil enzymes would be responsible for the oxidation activity observed at more than several kGy. In non-irradiated soil about half of the oxidation activity was considered resulting from abiotic soil enzymes. (author)

Field GE gamma spectrometry for on site measurements of some parameters characterizing radon-222 exhalation rates from soils and covers

International Nuclear Information System (INIS)

Zettwoog, P.; Kobal, I.; Pineau, J.F.

1997-01-01

We describe a new method based on differential gamma spectrometry for on site determination of some of the parameters which are relevant for the production of radon 222 in soil gas and its transfer from soil to indoor and outdoor atmospheres. This method is investigated in the context of a 3-year Slovenian-French cooperation programme, the PROTEUS project. We are currently using a germanium detector of 100 cm 3 . The height of the 20 deg. C collimated detector above the soil surface is from 1.5 to 3 m when using a tripod. This arrangement provides results which are representative of soil areas ranging from 1 to 4 square metres. Routine measurements would require larger detector volumes. The main objective is to provide technology and methodology for an efficient mapping of zones with potential for being the source of a high level of indoor radon, eliminating the need for soil sampling followed by laboratory analysis. The feasibility of an airborne mapping laboratory flying at low altitude will be investigated. Another objective is the rapid measurement of radon profiles across covers used to reduce exhalation rates from the surface of a pile of tailings, with characterisation of the influence of humidity content of the top layer. Airborne survey would allow for measuring exhalations from surfaces of slurries not otherwise accessible. (author)

Studying and measuring the gamma radiation doses in Homs city

International Nuclear Information System (INIS)

Sofaan, A. H.

2001-01-01

The gamma radiation dose was measured in Homs city by using many portable dosimeters (electronic dosimeter and Geiger-Muller). The measurements were carried out in the indoor and outdoor buildings, for different time period, through one year (1999-2000). High purity germanium detector with low back ground radiation (HpGe) was used to determine radiation element contained in some building and the surrounding soil. The statistical analysis laws were applied to make sure that the measured dose distribution around average value is normal distribution. The measurement indicates that the gamma indoor dose varies from 312μSv/y to 511μSv/y, with the average annual dose of 385μSv/y. However the gamma outdoor dose rate varies from 307μSv/y to 366μSv/y with an average annual dose 385μSv/y. The annual outdoor gamma radiation dose is about %16 lower than the outdoor dose in Homs City. These measurements have indicated that environmental gamma doses in Homs City are relatively low. This is because that most of the soils and rocks in the area are limestone. (author)

The gamma dose assessment and pH correlation for various soil types at Batu Pahat and Kluang districts, Johor, Malaysia

Science.gov (United States)

Johar, Saffuwan Mohamed; Embong, Zaidi; Tajudin, Saiful Azhar Ahmad

2016-01-01

An assessment of absorbed dose and radiation hazard index as well as its relationship with soil pH was performed in this study. The area was chosen due to its variety of soil types from the Alluvial and the Sedentary group. The radioactivity concentration levels and the soil acidity were measured using the Canberra GC3518 high pure germanium with a relative efficiency of 35% at 1.3 MeV and the Takemura Soil pH and Moisture Tester (DM15), respectively. Overall results show the Holyrood-Lunas soil of Alluvial group recorded the highest external terrestrial gamma radiation dose rate (TGRD) of 286.4±37.9 nGy h-1 and radioactivity concentrations of 78.1±8.9 Bq kg-1 (226Ra), 410.5±55.4 Bq kg-1 (232Th) and 56.4±8.8 Bq kg-1 (40K), respectively, while the Peat soil of Alluvial group recorded the lowest TGRD of 4.4±2.7 nGy h-1 and radioactivity concentrations of 4.8±1.7 Bq kg-1 (226Ra), 3.1±1.1 Bq kg-1 (232Th) and 6.1±2.0 Bq kg-1 (40K), respectively. The estimated mean outdoor annual effective dose, the mean radium equivalent activity (Req) and the mean external (Hext) and internal hazard index (Hint) associated with the alluvial and sedentary soil group were evaluated at 0.15 and 0.20 mSv, 280 and 364 Bq kg-1, Hext = 0.78 and 1.01, and Hint = 0.93 and 1.26, respectively. Correlation analysis between 238U, 232Th and 40K with soil pH level for alluvial group was r = +0.68, +0.48 and 0, respectively, while for sedentary soil, the Pearson's, r = -0.30, -0.90 and +0.14, respectively.

The use of proximal soil sensor data fusion and digital soil mapping for precision agriculture

OpenAIRE

Ji, Wenjun; Adamchuk, Viacheslav; Chen, Songchao; Biswas, Asim; Leclerc, Maxime; Viscarra Rossel, Raphael

2017-01-01

Proximal soil sensing (PSS) is a promising approach when it comes to detailed characterization of spatial soil heterogeneity. Since none of existing PSS systems can measure all soil information needed for implementation precision agriculture, sensor data fusion can provide a reasonable al- ternative to characterize the complexity of soils. In this study, we fused the data measured using a gamma-ray sensor, an apparent electrical conductivity (ECa) sensor, and a commercial Veris MS...

Improvement of vitamin B-6 production by gamma radiation in bacterial isolates from soil sample

International Nuclear Information System (INIS)

Trongpanich, Yanee; Anutrakunchai, Chitchanok; Piadang, Nattayana

2006-09-01

A vitamin B-6 producing bacterium, Rhizobium sp. 6.1C1 was isolated from soil and produced vitamin B-6 (mainly pyridoxamine) 0.27 mg per liter. Rhizobium sp. 6.1C1 is mesophile bacterium which was not able to grow at over 4 0C. The objective of this study was to improve vitamin B-6 production in high temperature by gamma radiation. The result showed that 677 mutant isolates which were obtained from irradiation dose 0.8 and 1 kGy, were able to grow at 5 0C. Only 4 isolates (08-361, 10-3, 10-94 and 10-98) showed high amount of vitamin B-6 per mg protein. From the results of optimum temperature and initial pH of medium showed high amount of vitamin B-6 per mg protein. From the results of optimum temperature and initial pH of medium showed that isolate 08-361 showed higher amount of vitamin b-6 than wild type. However, this value of vitamin B-6 from this mutant was lower than that when screening. Forms of produced vitamin B-6 from mutant were identified by HPLC. The result showed produced vitamin B-6 were PM and PMP, similar with wild type. Effect of gamma radiation stability of mutant is further study.

Environmental Gamma Radiation Measurements in Baskil District

International Nuclear Information System (INIS)

Canbazoglu, C.

2008-01-01

In this study, we have determined environmental gamma radiation dose rate in Baskil district which has very high granite content in its geographical structure. Gamma radiation dose rate measurements were achieved by portable radiation monitoring equipment based on the energy range between 40 keV and 1.3 MeV. The measurements were performed on asphalt and soil surface level and also one meter above the ground surface. The gamma dose rate was also performed inside and outside of buildings over the district. The dose rates were found to be between 8.46μR/h and 34.66 μR/h. Indoor and outdoor effective dose rate of the gamma radiation exposure has been calculated to be 523μSv/y and 196μSv/y, respectively

Population doses from terrestrial gamma exposure in China

International Nuclear Information System (INIS)

Ren, T.; Wang, Z.; Zhu, C.

1992-01-01

In order to estimate terrestrial gamma radiation exposure three nationwide surveys have been completed since 1981. The population-weighted outdoor and indoor arithmetic means of gamma dose rate based on momentary dose rate measurements using a NaI(Tl) environmental radiation meter and high-pressure ionisation chamber are, respectively, 80.3 nGy.h -1 and 120 nGy.h -1 . Based on integrating dose measurement using TLD CaSO 4 /Dy they are 67 nGy.h -1 and 89 nGy.h -1 respectively, and based on natural radionuclides concentrations in soil, determined by gamma spectroscopy analyses, they are 72.8 nGy.h -1 and 102 nGy.h -1 , respectively. These surveys were conducted independently by different groups. The best estimations of population-weighted gamma dose rates in China, based on all these surveys, would be 70 nGy.h -1 and 98 nGy.h -1 for outdoors and indoors, respectively. The annual average of effective dose equivalent is 0.56 mSv. These values are higher than the world averages estimated by UNSCEAR. The main reason is that the concentrations of 232 Th and 40 K in the soil of China are much higher than the world average estimated. (author)

Elementary representative sizes of soil attributes via attenuation of gamma rays and computerized tomography

International Nuclear Information System (INIS)

Borges, Jaqueline Aparecida Ribaski

2015-01-01

In this study, the Computed Tomography (CT) and gamma-ray attenuation (GRA) techniques were used in the investigation of representative sample sizes for attributes related to soil structure. First of all, the representative elementary length (REL) for experimental measurements of soil mass attenuation coefficient (μes), of samples from a sandy and a clayey soil, was analyzed. The study was conducted with two radioactive sources ( 241 Am and 137 Cs), three collimators (2 - 4 mm diameters), and 14 thickness (x) samples (2-5 cm). From these analyzes, it was possible to identify an ideal thickness range for each of the studied sources (2-4 cm and 12-15 cm for the sources of 241 Am and 137 Cs, respectively). The application of such results in representative elementary area evaluations, in clayey soil clods via CT, indicated that experimental soil mass attenuation coefficient average values obtained for x>4 cm and source 241 Am might induce the use of samples which are not large enough for soil bulk density evaluations. Subsequently, μCT images with a total volume of 39×39×33 mm 3 and spatial resolution of 60 μm were used for macroporous system morphological characterization of a Rhodic Ferralsol with clayey texture, under no-till (NT) and conventional till (CT) systems. Attributes as macroporosity (MAP), number of macropores (NMAP), tortuosity (τ) and connectivity (C) of the pores were assessed. The C degree was estimated based on the Euler-Poincare characteristic (EPC). Once 3D images enable the study of these attributes in different sample volumes, the proposed study is ideal for the analysis of representative elementary volume (REV). Usually, the selection of subvolumes for REV analysis occurs concentrically to a small volume or in adjacent positions. Here, we introduced a new method for selecting the positions of subvolumes, which are randomly chosen within the total image volume (random selection). It was observed that higher fluctuations in amplitude of each

Hydraulic conductivity determination of a dark red latosol by gamma attenuation and tensiometry

International Nuclear Information System (INIS)

Oliveira, Julio Cesar Martins de; Reichardt, Klaus; Costa, Antonio Carlos Saraiva da

1995-01-01

Results for the hydraulic conductivity of a dark red latosol (Oxisol) under laboratory and field conditions are presented. The laboratory experiments simulated field conditions through the measurement of the soil water content profiles as a function of time in soil columns. The data were obtained by the 241 Am gamma-ray transmission method, using standard gamma ray spectrometry equipment. Tensiometers at the depths of 10 and 25 cm were used to obtain the soil water content profiles as a function of time in the field experiments. The hydraulic conductivity functions were determined through internal soil drainage. The results showed higher values of the hydraulic conductivity measured in the field, compared with the laboratory values. The hydraulic conductivity determination methods presented distinct values for the field experiments as well as for the laboratory ones. (author)

Possibilities of using Eisenia Andrei earthworms as bioindicators of radioactive soil contamination

International Nuclear Information System (INIS)

Galanda, D.; Strisovska, J.; Lacenova, A.

2017-01-01

Eisenia Andrei is known under various generic names such as Californian daisy, red daisy, tiger worm etc. It is a species of earthworm that is physiologically adapted to life in a medium containing organic matter. Staining (vermiremedia technology) of soils contaminated with heavy metals belongs among innovative and efficient techniques. According to published works, this technology is easy to apply. Dandelions are used for soil rehabilitation, rejuvenation and mineral enrichment in the soil. In the soil environment, the effect of the sunsets is known as the drilosphere of the system, that is, the soil is under their direct influence. The aim of the present paper was to verify the possibility of application and subsequent use of Eisenia Andrei sunflowers as bioindicators in soil contaminated by radionuclides "2"3"9Pu and "2"4"1Am, which are significant anthropogenic radionuclides emitting alpha particles. Another circle of radionuclides were anthropogenic radionuclides "6"0Co and "1"3"7Cs emitting gamma rays. Based on the radionuclides used, two groups of target-contaminated samples were subjected to experimentation and spectrometric analysis alone. The first group of experimental subjects was made up of earthworms living in alpha radionuclide-enriched soils, and in the second group of gamma-radionuclides. Radiochemical analysis of alpha radionuclides was performed by a separation method of extraction chromatography using commercial sorbents from Triskem-TEVA Resin and DGA Resin. The preparation of specimens for the spectroscopic analysis of the emitted alpha configuration was performed by co-precipitation with NdCl_3. The measurement itself was performed with the ORTEC 576A Alpha Spectrometer with the GammaVision software. The activity of gamma radionuclides in a sample of animals devoid of possible surface contamination from the nutrient medium of the contaminated soil was measured using the Ortec gamma spectrometer. (authors)

Soil gamma ray spectrometry of the Buquira river basin, SP, Brazil; Gamametria de solos da bacia do rio Buquira, SP, Brazil

Energy Technology Data Exchange (ETDEWEB)

Rivera, Alice

2002-12-01

Natural radioactivity found in rocks and its evaluation been frequently used for studies of environmental geochemistry, particularly those of detection and control of pollutants and the consequent changes in environment after antropic interferences. In this work natural radioactivity in forty nine soil samples in the basin of Buquira river, at the Northeast region of Sao Paulo State, has been analysed and measured with a Ge-HP gamma ray spectrometer. A table with the most relevant results found in rocks is shown and discussed. (author)

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

International Nuclear Information System (INIS)

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

1996-01-01

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

Effect of gamma-irradiated sludge on the growth and yield of rice (Oryza sativa L. var. GR-3)

International Nuclear Information System (INIS)

Pandya, G.A.; Prakash, L.; Devasia, Preston; Modi, V.V.

1988-01-01

The effects of gamma-irradiated sludge on the growth and yield of rice (Oryza sativa L. var. GR-3) in pot cultures have been studied. Compared to plants grown only in soil, shoot length, root length, fresh weight, dry weight, total proteins, total soluble sugars, starch and chlorophyll content of plants grown in soil supplemented with unirradiated or gamma-irradiated sludge were found to be significantly increased. Irradiation of sludge significantly stimulated the linear growth of shoot and root systems as well as fresh and dry weights of plants, compared to those grown in soil containing unirradiated sludge. There was also an improvement in the grain yield (weight of seed) when plants were grown in soil supplemented with irradiated sludge. The results obtained suggest that the gamma-irradiated sewage sludge can be beneficially recycled for agricultural uses. (author)

Measurement of radionuclide activities of uranium-238 series in soil samples by gamma spectrometry: case of Vinaninkarena

International Nuclear Information System (INIS)

Randrianantenaina, F.R.

2017-01-01

The aim of this work is to determine the activity level of radionuclides of uranium-238 series. Eight soil samples are collected at Rural Commune of Vinaninkarena. After obtaining secular equilibrium, these samples have been measured using gamma spectrometry system in the Nuclear Analyses and Techniques Department of INSTN-Madagascar, with HPGe detector (30 % relative efficiency) and a Genie 2000 software. Activities obtained vary from (78±2)Bq.kg -1 to (49 231 ± 415)Bq.kg -1 . Among these eight samples, three activity levels are shown. Low activity is an activity which has value lower or equal to (89±3)Bq.kg -1 . Average activity is an activity which has value between (186± 1)Bq.kg -1 and (1049 ±7)Bq.kg -1 . And high activity is an activity which has value higher or equal to (14501±209)Bq.kg -1 . According to UNSCEAR 2000, these value are all higher than the world average value which is 35 Bq.kg -1 .It is due to the localities of sampling points. The variation of the activity level depends on radionuclide concentration of uranium-238 series in the soil. [fr

Study of stability of humic acids from soil and peat irradiated by gamma rays; Estudo da estabilidade de acidos humicos extraidos de solo e turfa, frente a radiacao ionizante gama

Energy Technology Data Exchange (ETDEWEB)

Silva, Wilson Tadeu Lopes da

1995-07-01

Humic acids samples (one deriving from a sedimentary soil and other from a peat), in aqueous media, were irradiated with gamma rays, in doses of 10, 50 and 100 kGy, in order to understand their chemical behavior after the irradiation. The material, before and after irradiation, was analyzed by Elemental Analysis, Functional Groups (carboxylic acids and phenols), UV/Vis Spectroscopy (E{sub 4}/E{sub 6} ratio), IR spectroscopy, CO{sub 2} content and Gel permeation Chromatography (GPC) ). The Elemental Analysis showed the humic acid derived from a peat had a most percentage quantity of Carbon and Hydrogen than the material from a sedimentary soil. From the UV/Vis Spectroscopy, it was observed a decrease of E{sub 4}/E{sub 6} ratio with an increase of the applied dose. The data from GPC are in agreement with this. The results showed that the molecular weight of the material increased by exposing it to a larger radiolitical dose. The peat material was less affected by the gamma radiation than the soil material. The carboxylic groups were responsible by radiochemical behavior of the material. (author)

Hymenobacter swuensis sp. nov., a gamma-radiation-resistant bacteria isolated from mountain soil.

Science.gov (United States)

Lee, Jae-Jin; Srinivasan, Sathiyaraj; Lim, Sangyong; Joe, Minho; Lee, Sang Hee; Kwon, Shin Ae; Kwon, Yoon Jung; Lee, Jin; Choi, Jin Ju; Lee, Hye Min; Auh, Young Kyung; Kim, Myung Kyum

2014-03-01

Gram stain-negative and non-motile bacteria, designated as DY53(T) and DY43, were isolated from mountain soil in South Korea prior exposure with 5 kGy gamma radiation. Phylogenetic analysis based on 16S rRNA gene sequence revealed that the strains belonged to the family Cytophagaceae in the class Cytophagia. 16S rRNA gene sequence similarity of strains DY53(T) and DY43 was 100 %. The highest degrees of sequence similarities of strains DY53(T) and DY43 were found with Hymenobacter perfusus A1-12(T) (98.8 %), Hymenobacter rigui WPCB131(T) (98.5 %), H. yonginensis HMD1010(T) (97.9 %), H. xinjiangensis X2-1g(T) (96.6 %), and H. gelipurpurascens Txg1(T) (96.5 %). The DNA G+C content of the novel strains DY53(T) and DY43 were 59.5 mol%. Chemotaxonomic data revealed that strains possessed major fatty acids such as C₁₅:₀ iso, C₁₅:₀ anteiso, C₁₆:₁ ω5c, summed feature 3 (16:1 ω7c/ω6c), summed feature 4 (17:1 anteiso B/iso I) and C₁₇:₀ iso, and major polar lipid was phosphatidylethanolamine. The novel strains showed resistance to gamma radiation, with a D10 value (i.e., the dose required to reduce the bacterial population by tenfold) in excess of 5 kGy. Based on these data, strains DY53(T) and DY43 should be classified as representing a novel species, for which the name Hymenobacter swuensis sp. nov. is proposed, with the type strain DY53(T) (=KCTC 32018(T) = JCM 18582(T)) and DY43 (=KCTC 32010).

Population doses from terrestrial gamma exposure in China

Energy Technology Data Exchange (ETDEWEB)

Ren, T.; Wang, Z.; Zhu, C. (Ministry of Public Health, Beijing, BJ (China))

1992-01-01

In order to estimate terrestrial gamma radiation exposure three nationwide surveys have been completed since 1981. The population-weighted outdoor and indoor arithmetic means of gamma dose rate based on momentary dose rate measurements using a NaI(Tl) environmental radiation meter and high-pressure ionisation chamber are, respectively, 80.3 nGy.h[sup -1] and 120 nGy.h[sup -1]. Based on integrating dose measurement using TLD CaSO[sub 4]/Dy they are 67 nGy.h[sup -1] and 89 nGy.h[sup -1] respectively, and based on natural radionuclides concentrations in soil, determined by gamma spectroscopy analyses, they are 72.8 nGy.h[sup -1] and 102 nGy.h[sup -1], respectively. These surveys were conducted independently by different groups. The best estimations of population-weighted gamma dose rates in China, based on all these surveys, would be 70 nGy.h[sup -1] and 98 nGy.h[sup -1] for outdoors and indoors, respectively. The annual average of effective dose equivalent is 0.56 mSv. These values are higher than the world averages estimated by UNSCEAR. The main reason is that the concentrations of [sup 232]Th and [sup 40]K in the soil of China are much higher than the world average estimated. (author).

Measuring naturally occurring uranium in soil and minerals by analysing the 352 keV gamma-ray peak of 214Pb using a NaI(Tl)-detector

International Nuclear Information System (INIS)

Bezuidenhout, J.

2013-01-01

This article investigates the prospect of utilising the 351.9 keV gamma-ray of 214 Pb when determining the concentration of uranium. Soil samples were collected from various locations around South Africa and laboratory gamma ray spectra for each were obtained by means of a NaI(Tl)-detector (7.62×7.62 cm 2 ). The potassium, uranium and thorium concentrations where extracted by analysing gamma ray peaks that are associated with these radionuclides. Two separate uranium concentrations were extracted; one by means of the 214 Pb decay and the other one by means of the 214 Bi decay. These uranium concentrations were compared in terms of accuracies and detection limits. - Highlights: • Investigated a method to improve uranium concentrations measurements. • Expansion on an existing method that analyses naturally occurring radionuclides. • Utilise pill containers opposed to Marrinelli beakers. • Possible application to in situ measurements. • The method utilise NaI(Tl)-detectors with relative high efficiency

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

Science.gov (United States)

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.

Determination of the Concentration of Radioactive Nuclides of Surface Soils of some Hadhramout's Valleys in Yemen Using Gamma-Ray Spectrometry

International Nuclear Information System (INIS)

Bazohair, A. O.; Bayashoot, A. K.; AL-Shamy, A. A.

2004-01-01

In this research five surface soil samples have been taken from some Hadhramout's valleys in Yemen (Khrid , Arf , Huwayrah , Buwaish, Khirba ) in the years from (1999) to (2002) and analyzed using gamma-ray spectrometry. The spectra of samples were measured using multichannel analyzer (MCA) that was connected with measurement system for this purpose.A high purity germanium(Hp Ge) detector with resolution of (2.11 keV) at gamma-line(1332 keV) of radioactive source(Co-60) used for detecting ( U 238 , Th 232 , K 40 , Cs 137 ) in the samples. The results showed that the average concentration of radioactive nuclides in the samples of uranium ranged from(37.56 Bq/Kg) to(46.58 Bq/Kg) and for thorium ranged from(37.93 Bq/Kg) to(47.28 Bq/Kg) and for potassium ranged from(347.57 Bq/Kg) to(850.10 Bq/Kg) and for cesium ranged from(6.94 Bq/Kg) to(15.86 Bq/Kg) and the measured precision of samples ranged from(4.71%) to (9.23%). (authors)

Calibration of a Gamma Spectrometry System Used for the Determination of Cs-137 in Spanish Soils; Puesta a Punto de un sistema de Expectrometria Gamma para la Determinacion de Cs-137 en Suelos Espanoles

Energy Technology Data Exchange (ETDEWEB)

Barreraa, M.; Romero, M. L.; Valino, F.

2008-07-01

The document describes the methodology used at CIEMAT in order to determine, by gamma spectrometry, the background levels of the radionuclide Cs-137 in soils of the Spanish peninsular territory. the work is a part of an extensive research project developed jointly by the University of the Basque Country (UPV-EHU) and the CIEMAT, endellite Content and migration of radiocaesium and radiostrontium in Spanish soils, which is funded by the Plan I+D of the Spanish Nuclear Security Council (CSN). The objective of the project is to establish the reference levels of man-made radionuclides in Spanish soils, with respect to which the evaluation of a possible posterior accidental release of radioactive material could be appraised. The activity concentration of the fission products Cs-137 has been determined in 34 soil cores extracted from representative Spanish soils type zones. This publication describes the experimental system employed, its calibration, the particular conditions applied to perform the measurements, as well as the experimental validation of the methodology. The activity profiles and inventories of the radioactive element so obtained are also presented. The estimation of the background Cs-137 reference levels, will provide a basis for later applications as the study of the spatial distribution in the region, the determination of the correlation between the deposited activity and the meteorological conditions, or the calculation of the specific migration parameters of the radioactive elements in Mediterranean conditions. (Author) 15 refs.

Neutron activation and radiometric investigation of Kazakhstan soils

International Nuclear Information System (INIS)

Gwozdz, R.; Popov, J.V.; Shishkov, I.A.; Poznyak, V.; Solodukhin, V.P.

2001-01-01

Full text: Great diversity of radio-ecological problems requires measurement of materials with vastly differing chemical composition and density, and varying volume. In case of gamma spectrometry such variation in composition, density and volume changes the response of a measuring system quite drastically. A necessary correction is usually achieved by applying one of the four correction methods. The first one is applying a standard with composition as close to the measured sample as possible. The second method needs some previous knowledge about the chemical composition of the sample and a subsequent calculation of the mass absorption coefficient. The third method, an intensity ratio of two gamma lines, can only be applied when an isotope in the investigated sample has two measurable gamma lines. The fourth method consists in an additional gamma transmission measurement, using an isotopic source. Application of the first two methods to samples collected in Kazakhstan is evaluated and the results achieved are described. Instrumental neutron activation analysis by either long, or short irradiation was applied to three groups of samples. The first 15 samples were from the Semipalatinsk area, the next 15 from the area north for the Kara-Tau range. The third group of 5 samples was from the Syr-Darya valley. The Kara-Tau and Syr-Darya samples originate from the area adjacent to an uranium mining site. Only two samples are collected at cultivated soil, all the other are collected at the steppe or semi-desert areas, In the additional group measured there were ten sub-samples of the environmental soil standard, prepared at the Institute of Nuclear Physics. Activation analysis was applied as well to Soil-6 and Soil IAEA-375, two reference materials distributed by IAEA. Determination of concentration of about 40 elements in very sample enabled computation of mass absorption coefficients for all the investigated samples. Results of calculation and experimental testing prove

Environmental gamma radiation measurement in District Swat (Pakistan))

International Nuclear Information System (INIS)

Jabbar, T.; Khan, K.; Akhter, P.; Jabbar, A.; Subhani, M.S.

2008-01-01

External exposure to environmental gamma ray sources is an important component of exposure to the public. A survey was carried out to determine activity concentration levels and associated doses from 226 Ra, 232 Th, 40 K and 137 Cs by means of high-resolution gamma ray spectrometry in the Swat district, famous for tourism. The mean concentrations for 226 Ra, 232 Th and 40 K were found to be 50.4 ± 0.7, 34.8 ± 0.7 and 434.5 ± 7.4 Bq kg -1 , respectively, in soil samples, which are slightly more than the world average values. However, 137 Cs was only found in the soil sample of Barikot with an activity concentration of 34 ± 1.2 Bq kg -1 . Only 40 K was determined in vegetation samples with an average activity of 172.2 ± 1.7 Bq kg -1 , whereas in water samples, all radionuclides were found below lower limits of detection. The radium equivalent activity in all soil samples is lower than the limit set in the Organisation for Economic Cooperation and Development report (370 Bq kg -1 ). The value of the external exposure dose has been determined from the content of these radionuclides in soil. The average terrestrial gamma air absorbed dose rate was observed to be 62.4 nGy h -1 , which yields an annual effective dose of 0.08 mSv. The average value of the annual effective dose lies close to the global range of outdoor radiation exposure given in United Nations Scientific Committee on the Effects of Atomic Radiation. However, the main component of the radiation dose to the population residing in the study area arises from cosmic ray due to high altitude. (authors)

Determining a pre-mining radiological baseline from historic airborne gamma surveys: A case study

International Nuclear Information System (INIS)

Bollhöfer, Andreas; Beraldo, Annamarie; Pfitzner, Kirrilly; Esparon, Andrew; Doering, Che

2014-01-01

Knowing the baseline level of radioactivity in areas naturally enriched in radionuclides is important in the uranium mining context to assess radiation doses to humans and the environment both during and after mining. This information is particularly useful in rehabilitation planning and developing closure criteria for uranium mines as only radiation doses additional to the natural background are usually considered ‘controllable’ for radiation protection purposes. In this case study we have tested whether the method of contemporary groundtruthing of a historic airborne gamma survey could be used to determine the pre-mining radiological conditions at the Ranger mine in northern Australia. The airborne gamma survey was flown in 1976 before mining started and groundtruthed using ground gamma dose rate measurements made between 2007 and 2009 at an undisturbed area naturally enriched in uranium (Anomaly 2) located nearby the Ranger mine. Measurements of 226 Ra soil activity concentration and 222 Rn exhalation flux density at Anomaly 2 were made concurrent with the ground gamma dose rate measurements. Algorithms were developed to upscale the ground gamma data to the same spatial resolution as the historic airborne gamma survey data using a geographic information system, allowing comparison of the datasets. Linear correlation models were developed to estimate the pre-mining gamma dose rates, 226 Ra soil activity concentrations, and 222 Rn exhalation flux densities at selected areas in the greater Ranger region. The modelled levels agreed with measurements made at the Ranger Orebodies 1 and 3 before mining started, and at environmental sites in the region. The conclusion is that our approach can be used to determine baseline radiation levels, and provide a benchmark for rehabilitation of uranium mines or industrial sites where historical airborne gamma survey data are available and an undisturbed radiological analogue exists to groundtruth the data. - Highlights: �

External exposure from radionuclides in soil: analytical vs. simulation procedures

International Nuclear Information System (INIS)

Velasco, Hugo; Rizzotto, Marcos

2008-01-01

Full text: The external gamma irradiation resulting from radionuclides deposited on the ground surface can be an important source of radiation exposure. The assessment of this irradiation is extremely complex due to the large number of environmental factors which affect the gamma photon flux in air originating from the ground. The source energy affects the interaction between the radiation and the medium, and the characteristics and the properties of the soil are the most relevant factors to determine the energy and the angular distribution of gamma radiation in air 1 m above the ground surface. From an analytical point of view the calculations are based on the point-kernel integration method and assume that the source concentration at any depth in soil is uniform over an infinite surface parallel to the ground plane. The dose-rate factor is applied to environmental dose assessments by means of the general equation: H(t)= χ (t) x DRF where H is the external dose rate at time t, χ is the source concentration at the location of the exposed individual, and DRF is the dose-rate factor. Dose-rate factors in air at a height of 1 m above ground are tabulated for discrete photon energies between 0.01 and 10 MeV and for source depths in soil between 0 and 300 cm. These factors were determined for sources distributed in a slab of finite thickness and sources which are exponentially distributed with depth. A Monte Carlo algorithm was developed to simulate the gamma photons transport calculation for the soil/air configuration. In this case the soil constituents were assumed to be similar to those on the earth's crust. The model considers the gamma photons source distributed uniformly in the soil profile, from the ground surface to a depth beyond which the soil is considered uncontaminated. Source gamma photons were randomly selected from the contaminated soil zone and their subsequent interactions determined by the probability of occurrence via photoelectric effect, Compton

Effects of of habitats and pesticides on aerobic capacity and survival of soil fauna.

Science.gov (United States)

Tripathi, G; Sharma, B M

2005-06-01

Faunal health is largely dependent on their soil environment and available litter quality. So the effects of different soil habitats and pesticides on citrate synthase (CS) activity of soil fauna and its population were studied. The soil animals were collected from different pedoecosystems for habitat study. Whereas Vigna radiata based system was selected for pesticidal observations. The field was divided into five equal plots for control and treatment of gamma-BHC, quinalphos, carbaryl and cypermethrin. Soil fauna was collected by quadrat method and extracted by Tullgren funnel. Individuals of a species having similar sizes were collected for the estimation of CS activity. They were homogenized and fractions were obtained by differential centrifugation. The activity of CS was assayed spectrophotometrically. Citrate synthase (CS) activity of beetle (Rasphytus fregi), woodlouse (Porcellio laevis) and centipede (Scolopendra morsitans) varied significantly with respect to changes in different soil habitats. Though the CS activity of R. fregi, P. laevis, and S. morsitans differed among themselves but the highest activity of CS in these animals was in V. radiata and lowest in A. nilotica based pedoecosystem. The aerobic capacity of centipede was maximum followed by woodlouse and beetle. The treatment of gamma-BHC, quinalphos, carbaryl and cypermethrin significantly reduced the CS activity of these animals. Gamma-BHC showed maximum reduction in CS activity indicating highly toxic effect of organochlorine on aerobic metabolism of soil fauna. However, minimum reduction was observed in response to carbaryl (in beetle) or cypermethrin (in woodlouse/centipede) leading to impairment of aerobic capacity. The differences in pesticide effects might be assigned to the differences in chemical nature of pesticides and their interactions with below-ground fauna. Treatment of gamma-BHC and quinalphos reduced the population of Acari, Coleoptera, Collembola, other arthropods as well as

The gamma dose assessment and pH correlation for various soil types at Batu Pahat and Kluang districts, Johor, Malaysia

Energy Technology Data Exchange (ETDEWEB)

Johar, Saffuwan Mohamed, E-mail: saffuwan@uthm.edu.my [Department of Science, Faculty of Science, Technology and Human Development, Universiti Tun Hussein Onn Malaysia (Malaysia); Embong, Zaidi [Department of Science, Faculty of Science, Technology and Human Development, Universiti Tun Hussein Onn Malaysia (Malaysia); Research Center for Soft Soil (RECESS), Faculty of Civil and Environmental Engineering, Universiti Tun Hussein Onn Malaysia (Malaysia); Tajudin, Saiful Azhar Ahmad [Research Center for Soft Soil (RECESS), Faculty of Civil and Environmental Engineering, Universiti Tun Hussein Onn Malaysia (Malaysia)

2016-01-22

An assessment of absorbed dose and radiation hazard index as well as its relationship with soil pH was performed in this study. The area was chosen due to its variety of soil types from the Alluvial and the Sedentary group. The radioactivity concentration levels and the soil acidity were measured using the Canberra GC3518 high pure germanium with a relative efficiency of 35% at 1.3 MeV and the Takemura Soil pH and Moisture Tester (DM15), respectively. Overall results show the Holyrood-Lunas soil of Alluvial group recorded the highest external terrestrial gamma radiation dose rate (TGRD) of 286.4±37.9 nGy h{sup −1} and radioactivity concentrations of 78.1±8.9 Bq kg{sup −1} ({sup 226}Ra), 410.5±55.4 Bq kg{sup −1} ({sup 232}Th) and 56.4±8.8 Bq kg{sup −1} ({sup 40}K), respectively, while the Peat soil of Alluvial group recorded the lowest TGRD of 4.4±2.7 nGy h{sup −1} and radioactivity concentrations of 4.8±1.7 Bq kg{sup −1} ({sup 226}Ra), 3.1±1.1 Bq kg{sup −1} ({sup 232}Th) and 6.1±2.0 Bq kg{sup −1} ({sup 40}K), respectively. The estimated mean outdoor annual effective dose, the mean radium equivalent activity (R{sub eq}) and the mean external (H{sub ext}) and internal hazard index (H{sub int}) associated with the alluvial and sedentary soil group were evaluated at 0.15 and 0.20 mSv, 280 and 364 Bq kg{sup −1}, H{sub ext} = 0.78 and 1.01, and H{sub int} = 0.93 and 1.26, respectively. Correlation analysis between 238U, {sup 232}Th and {sup 40}K with soil pH level for alluvial group was r = +0.68, +0.48 and 0, respectively, while for sedentary soil, the Pearson’s, r = −0.30, −0.90 and +0.14, respectively.

Pyrosequencing Based Microbial Community Analysis of Stabilized Mine Soils

Science.gov (United States)

Park, J. E.; Lee, B. T.; Son, A.

2015-12-01

Heavy metals leached from exhausted mines have been causing severe environmental problems in nearby soils and groundwater. Environmental mitigation was performed based on the heavy metal stabilization using Calcite and steel slag in Korea. Since the soil stabilization only temporarily immobilizes the contaminants to soil matrix, the potential risk of re-leaching heavy metal still exists. Therefore the follow-up management of stabilized soils and the corresponding evaluation methods are required to avoid the consequent contamination from the stabilized soils. In this study, microbial community analysis using pyrosequencing was performed for assessing the potential leaching of the stabilized soils. As a result of rarefaction curve and Chao1 and Shannon indices, the stabilized soil has shown lower richness and diversity as compared to non-contaminated negative control. At the phyla level, as the degree of contamination increases, most of phyla decreased with only exception of increased proteobacteria. Among proteobacteria, gamma-proteobacteria increased against the heavy metal contamination. At the species level, Methylobacter tundripaludum of gamma-proteobacteria showed the highest relative portion of microbial community, indicating that methanotrophs may play an important role in either solubilization or immobilization of heavy metals in stabilized soils.

Gamma-ray Full Spectrum Analysis for Environmental Radioactivity by HPGe Detector

Science.gov (United States)

Jeong, Meeyoung; Lee, Kyeong Beom; Kim, Kyeong Ja; Lee, Min-Kie; Han, Ju-Bong

2014-12-01

Odyssey, one of the NASA¡¯s Mars exploration program and SELENE (Kaguya), a Japanese lunar orbiting spacecraft have a payload of Gamma-Ray Spectrometer (GRS) for analyzing radioactive chemical elements of the atmosphere and the surface. In these days, gamma-ray spectroscopy with a High-Purity Germanium (HPGe) detector has been widely used for the activity measurements of natural radionuclides contained in the soil of the Earth. The energy spectra obtained by the HPGe detectors have been generally analyzed by means of the Window Analysis (WA) method. In this method, activity concentrations are determined by using the net counts of energy window around individual peaks. Meanwhile, an alternative method, the so-called Full Spectrum Analysis (FSA) method uses count numbers not only from full-absorption peaks but from the contributions of Compton scattering due to gamma-rays. Consequently, while it takes a substantial time to obtain a statistically significant result in the WA method, the FSA method requires a much shorter time to reach the same level of the statistical significance. This study shows the validation results of FSA method. We have compared the concentration of radioactivity of 40K, 232Th and 238U in the soil measured by the WA method and the FSA method, respectively. The gamma-ray spectrum of reference materials (RGU and RGTh, KCl) and soil samples were measured by the 120% HPGe detector with cosmic muon veto detector. According to the comparison result of activity concentrations between the FSA and the WA, we could conclude that FSA method is validated against the WA method. This study implies that the FSA method can be used in a harsh measurement environment, such as the gamma-ray measurement in the Moon, in which the level of statistical significance is usually required in a much shorter data acquisition time than the WA method.

Gamma-ray Full Spectrum Analysis for Environmental Radioactivity by HPGe Detector

Directory of Open Access Journals (Sweden)

Meeyoung Jeong

2014-12-01

Full Text Available Odyssey, one of the NASA’s Mars exploration program and SELENE (Kaguya, a Japanese lunar orbiting spacecraft have a payload of Gamma-Ray Spectrometer (GRS for analyzing radioactive chemical elements of the atmosphere and the surface. In these days, gamma-ray spectroscopy with a High-Purity Germanium (HPGe detector has been widely used for the activity measurements of natural radionuclides contained in the soil of the Earth. The energy spectra obtained by the HPGe detectors have been generally analyzed by means of the Window Analysis (WA method. In this method, activity concentrations are determined by using the net counts of energy window around individual peaks. Meanwhile, an alternative method, the so-called Full Spectrum Analysis (FSA method uses count numbers not only from full-absorption peaks but from the contributions of Compton scattering due to gamma-rays. Consequently, while it takes a substantial time to obtain a statistically significant result in the WA method, the FSA method requires a much shorter time to reach the same level of the statistical significance. This study shows the validation results of FSA method. We have compared the concentration of radioactivity of 40K, 232Th and 238U in the soil measured by the WA method and the FSA method, respectively. The gamma-ray spectrum of reference materials (RGU and RGTh, KCl and soil samples were measured by the 120% HPGe detector with cosmic muon veto detector. According to the comparison result of activity concentrations between the FSA and the WA, we could conclude that FSA method is validated against the WA method. This study implies that the FSA method can be used in a harsh measurement environment, such as the gamma-ray measurement in the Moon, in which the level of statistical significance is usually required in a much shorter data acquisition time than the WA method.

Soil Segregation Methods for Reducing Transportation and Disposal Costs - 13544

Energy Technology Data Exchange (ETDEWEB)

Frothingham, David; Andrews, Shawn; Barker, Michelle; Boyle, James; Buechi, Stephen; Graham, Marc; Houston, Linda; Polek, Michael; Simmington, Robert; Spector, Harold [U.S. Army Corps of Engineers, Buffalo District, 1776 Niagara St., Buffalo, NY 14207 (United States); Elliott, Robert ' Dan' [U.S. Army Reserve, 812A Franklin St.,Worcester, MA 01604 (United States); Durham, Lisa [Argonne National Laboratory, Environmental Science Division, 9700 S. Cass Ave., Argonne, IL 60439 (United States)

2013-07-01

At Formerly Utilized Sites Remedial Action Program (FUSRAP) sites where the selected alternative for contaminated soil is excavation and off-site disposal, the most significant budget items of the remedial action are the costs for transportation and disposal of soil at an off-site facility. At these sites, the objective is to excavate and dispose of only those soils that exceed derived concentration guideline levels. In situ soil segregation using gross gamma detectors to guide the excavation is often challenging at sites where the soil contamination is overlain by clean soil or where the contaminated soil is located in isolated, subsurface pockets. In addition, data gaps are often identified during the alternative evaluation and selection process, resulting in increased uncertainty in the extent of subsurface contamination. In response, the U.S. Army Corps of Engineers, Buffalo District is implementing ex situ soil segregation methods. At the remediated Painesville Site, soils were excavated and fed through a conveyor-belt system, which automatically segregated them into above- and below-cleanup criteria discharge piles utilizing gamma spectroscopy. At the Linde Site and the Shallow Land Disposal Area (SLDA) Site, which are both in the remediation phase, soils are initially segregated during the excavation process using gross gamma detectors and then transported to a pad for confirmatory manual surveying and sampling. At the Linde Site, the ex situ soils are analyzed on the basis of a site-specific method, to establish compliance with beneficial reuse criteria that were developed for the Linde remediation. At the SLDA Site, the ex situ soils are surveyed and sampled based on Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) final status survey guidance to demonstrate compliance with the derived concentration guideline levels. At all three sites, the ex situ soils that meet the site- specific DCGLs are retained on-site and used as backfill

Soil Segregation Methods for Reducing Transportation and Disposal Costs - 13544

International Nuclear Information System (INIS)

Frothingham, David; Andrews, Shawn; Barker, Michelle; Boyle, James; Buechi, Stephen; Graham, Marc; Houston, Linda; Polek, Michael; Simmington, Robert; Spector, Harold; Elliott, Robert 'Dan'; Durham, Lisa

2013-01-01

At Formerly Utilized Sites Remedial Action Program (FUSRAP) sites where the selected alternative for contaminated soil is excavation and off-site disposal, the most significant budget items of the remedial action are the costs for transportation and disposal of soil at an off-site facility. At these sites, the objective is to excavate and dispose of only those soils that exceed derived concentration guideline levels. In situ soil segregation using gross gamma detectors to guide the excavation is often challenging at sites where the soil contamination is overlain by clean soil or where the contaminated soil is located in isolated, subsurface pockets. In addition, data gaps are often identified during the alternative evaluation and selection process, resulting in increased uncertainty in the extent of subsurface contamination. In response, the U.S. Army Corps of Engineers, Buffalo District is implementing ex situ soil segregation methods. At the remediated Painesville Site, soils were excavated and fed through a conveyor-belt system, which automatically segregated them into above- and below-cleanup criteria discharge piles utilizing gamma spectroscopy. At the Linde Site and the Shallow Land Disposal Area (SLDA) Site, which are both in the remediation phase, soils are initially segregated during the excavation process using gross gamma detectors and then transported to a pad for confirmatory manual surveying and sampling. At the Linde Site, the ex situ soils are analyzed on the basis of a site-specific method, to establish compliance with beneficial reuse criteria that were developed for the Linde remediation. At the SLDA Site, the ex situ soils are surveyed and sampled based on Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) final status survey guidance to demonstrate compliance with the derived concentration guideline levels. At all three sites, the ex situ soils that meet the site- specific DCGLs are retained on-site and used as backfill

Airborne Gamma-Ray Survey in Latvia 1995/96

DEFF Research Database (Denmark)

Bargholz, Kim

1998-01-01

Based on Airborne Gamma-Ray Spectrometry measurements performed with the Danish AGS equipment in 1995 and 1996 maps of the natural radioactivity have been produdced for selected areas in Latvia. The calibration of the quipment have been improved by comparisons with soil sample measurements....

Effect Of GAMMA Radiation On Antimicrobial Activity And Chemical Constituents Of Marjoram (Majorana Hortensis Essential Oil

International Nuclear Information System (INIS)

GALAL, Y.G.M.; EL-GHANDOUR, I.A.; ABOU SEER, A.M.M.; DESOUKY, E.M.; ARAFA, R.A.

2010-01-01

Field experiment was set up to study the response of marjoram plant grown on sandy soil and inoculated with Bradyrhizobium sp. and/or B. polymixa in combination with organic fertilizers. The extracted oil was irradiated with gamma irradiation at doses of 10, 20, 30, 40 and 50 kGy. The chemical constituents of the essential oils were analyzed by GC-Ms techniques after exposure to gamma radiation. The gamma irradiated essential oils of marjoram were tested for their antimicrobial activities against some pathogenic microorganisms i.e. Klebsiella pneumoniae, Bacillus cereus, Staphylococcus aureus, Salmonella enteritidis, Pseudomonas citri, Fusarium oxysporum, Aspergillus niger, Trichoderma viride and Aspergillus flavus. Extracted oil was the best when soil was treated with faba bean straw and inoculated with B. polymixa + Bradyrhizobium sp. Similarly, the extracted oil from plant cultivated in soil treated with sheep manure in combination with B. polymixa recorded the highest value. Results also revealed that gamma irradiation doses increased the antimicrobial activity with different magnitudes. The essential oil extracted from herb exposed to 30 kGy was found to be the most active antimicrobial with slight increases in the main components.

The error sources appearing for the gamma radioactive source measurement in dynamic condition

International Nuclear Information System (INIS)

Sirbu, M.

1977-01-01

The error analysis for the measurement of the gamma radioactive sources, placed on the soil, with the help of the helicopter are presented. The analysis is based on a new formula that takes account of the attenuation gamma ray factor in the helicopter walls. They give a complete error formula and an error diagram. (author)

Gamma dose rate changes in buildings in the region of Southeastern Iran using thermoluminescence dosimetry

International Nuclear Information System (INIS)

Jomehzadeh Mahani, A.; Bahreyni Toosi, M.T.

2006-01-01

Introduction: It is important to measure background radiation, because human beings are always exposed to environmental radiation. The terrestrial component of the natural background depends on the compositions of soils and rocks in which are contained. A significant contribution to total dose from natural sources comes from terrestrial radionuclides such as U- 238, Th- 232 and K- 40. The level of gamma dose rate in buildings depends on the climate / weather, ventilation of living environment, local geology, drainage patterns and other factors. The objective of this study was to establishing the distribution of environmental gamma dose rates in the type of building sampled included cement-sand and soil brick buildings. Materials and Methods: Equipments used in this study include: 1-TLD-100 H (LiF: Mg, Cu, P) dosimeters. 2- TLD-Reader 3500 made by Harshaw, USA. In order to determine indoor gamma dose rate, the dosimeters were calibrated at room temperature with Co-60 source. Before using the dosimeters to measure environmental dose they were subjected to the thermal treatment in a normal oven. Two TLDs, were embedded in a 5 mm PMMA mini-phantom to register only gamma ray. 20 buildings for this study chosen randomly throughout Kerman town, southeastern Iran. Inside each building a holder was hung at a height of above 3 m. The period of monitoring of TLDs was 15 days. The TLDs were retrieved from the buildings and taken to the Mashhad university of medical sciences where they were read with a Harshaw TLD reader model 3500. Results: Our results indicate that indoor gamma dose rate ranged from 106 n Sv/h to 133 n Sv/h for cement-sand buildings with an average of 114.72 n Sv/h. For soil buildings the indoor gamma dose rate varied from 86 n Sv/h to 116 n Sv/h with an average of 100.50 n Sv/h. While the average gamma dose rate in cement-sand buildings is highest (114.72 n Sv/h), that of soil buildings is lowest (100.50 n Sv/h). Discussion: Average values vary from building

Gamma dose rate changes in buildings in the region of Southeastern Iran using thermoluminescence dosimetry

Energy Technology Data Exchange (ETDEWEB)

Jomehzadeh Mahani, A. [Hormozgan un Univ. of medical sciences, Paramedical School, Bandarabbas (Iran, Islamic Republic of); Bahreyni Toosi, M.T. [Mashhad Univ. of medical sciences, Medical school (Iran, Islamic Republic of)

2006-07-01

oduction: It is important to measure background radiation, because human beings are always exposed to environmental radiation. The terrestrial component of the natural background depends on the compositions of soils and rocks in which are contained. A significant contribution to total dose from natural sources comes from terrestrial radionuclides such as U- 238, Th- 232 and K- 40. The level of gamma dose rate in buildings depends on the climate / weather, ventilation of living environment, local geology, drainage patterns and other factors. The objective of this study was to establishing the distribution of environmental gamma dose rates in the type of building sampled included cement-sand and soil brick buildings. Materials and Methods: Equipments used in this study include: 1-TLD-100 H (LiF: Mg, Cu, P) dosimeters. 2- TLD-Reader 3500 made by Harshaw, USA. In order to determine indoor gamma dose rate, the dosimeters were calibrated at room temperature with Co-60 source. Before using the dosimeters to measure environmental dose they were subjected to the thermal treatment in a normal oven. Two TLDs, were embedded in a 5 mm PMMA mini-phantom to register only gamma ray. 20 buildings for this study chosen randomly throughout Kerman town, southeastern Iran. Inside each building a holder was hung at a height of above 3 m. The period of monitoring of TLDs was 15 days. The TLDs were retrieved from the buildings and taken to the Mashhad university of medical sciences where they were read with a Harshaw TLD reader model 3500. Results: Our results indicate that indoor gamma dose rate ranged from 106 n Sv/h to 133 n Sv/h for cement-sand buildings with an average of 114.72 n Sv/h. For soil buildings the indoor gamma dose rate varied from 86 n Sv/h to 116 n Sv/h with an average of 100.50 n Sv/h. While the average gamma drate in cement-sand buildings is highest (114.72 n Sv/h), that of soil buildings is lowest (100.50 n Sv/h). Discussion: Average values vary from building to

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

International Nuclear Information System (INIS)

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

1995-01-01

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

Radioactive elements and earthworms in contaminated soils

International Nuclear Information System (INIS)

Suleymanova, A.S.; Abdullayev, A.S.; Ahmadov, G.S.; Naghiyev, J.A.; Samadov, P.A.

2010-11-01

Earthworms are one of the indispensable soil animals which treat soil with letting it through their gut and help increasing soil fertility. The effect of radioactive elements and comparative effect of heavy metals to the vital functions of earthworms were determined in laboratory conditions. Experiments were continued for a month, and first of all, each soil type, grey-brown soil from Ramana iodine plant territory of Baku city, brown soil from Aluminum plant territory of Ganja city, aborigine grey-brown soil of Absheron peninsula, treated with Ra and U salts as model variants and brown soil of Ganja city was analyzed by gamma-spectrometer for radionuclide determining at the beginning and at the end of the experiment. Earthworms (Nicodrilus Caliginosus Sav.trapezoides) aboriginal for Absheron peninsula and plant residues were added to the soil. At the end of the month the biomass, survival value, coprolite allocation value, food activity and catalase value in earthworms and in soil were determined. The gamma-spectrometric analysis results gave interesting values in coprolites, soils which had been treated through the earthworms' gut. In comparison with the initial variants in experimental results more percent of radioactivity was gathered in coprolites. By this way earthworms absorbed most of radioactive elements and allocated them as coprogenous substances on the upper layer of soil. During absorbing, some percents of radioactive elements were also gathered in gut cells of the earthworms. Thereby determination of some vital functions of earthworms was expedient. Thus, by the instrumentality of these experiments we can use earthworms for biodiagnosis and for bioremediation of contaminated soils with radionuclides and heavy metals.

Assessment of radiological significance of naturally occurring radionuclides in soil and rock matrices around Kakrapar environment

International Nuclear Information System (INIS)

Patra, A.K.; Jaison, T.J.; Baburajan, A.; Hegde, A.G.

2008-01-01

The activity and gamma-absorbed dose rate due to the naturally occurring radionuclides in the terrestrial environment such as 238 U, 232 Th and 40 K were determined in soil and rock samples collected around Kakrapar Atomic Power Plant site, using gamma-ray spectrometry. The mean concentration levels measured in Kakrapar soil from naturally occurring radioisotopes such as 238 U, 232 Th and 40 K are lower than the corresponding global average values obtained in worldwide soil. The external hazard index (Hex) and absorbed gamma dose rate in air outdoors is observed to be 0.04-0.18 and 3.1-14.1 nGy h -1 , respectively. (authors)

Behaviour of lindane (gamma HCH) in soil under laboratory conditions

International Nuclear Information System (INIS)

Bennaceur, M.; Ghezal, F.; Coste, C.M.

1997-01-01

The degradation of lindane in solid after multiple application was studied. The rate of disappearance of lindane increased at long periods after application. The dissipation of lindane was more rapid in soil collected from treated a plot than an untreated plot, owing to the degradation by micro-organisms suggesting that microorganisms had become adapted to degrade it. The rates of mineralization, mobility and degradation of lindane were also investigated under laboratory conditions using 14 C-labelled lindane. The results showed that most of the applied dose remained on the upper 6cm in the soil columns. Over a periods of three months, extractable residues, bound residues and evolution of 14 CO 2 were recorded. After 12 weeks, the soil contained about 50% of the initially applied 14 C and 20% was bound to the soil. The evolution of 14 CO 2 increased with time, amounting to 3.1% in non-sterile soil and less than 1% in sterile soil. The hexane 14 C-extractable residues were shown, by TLC, to contain lindane as the main product. (author). 5 refs, 4 tabs

THE POTENTIAL OF γ-RAY SPECTROSCOPY FOR SOIL PROXIMAL SURVEY IN CLAYEY SOILS

Directory of Open Access Journals (Sweden)

Simone Priori

2014-01-01

Full Text Available Gamma-ray spectroscopy surveys the intensity and distribution of γ-rays emitted from radionuclides of soils and bedrocks. The most important radionuclides of soils and rocks are: 40K, 232Th, 238U and 137Cs, the latter due to Chernobyl burst or radioactive pollution. Distribution and quantity of these radionuclides into the soil is strictly linked to parent material mineralogy and soil cation exchange capacity. The aim of this work is to show the makings of γ-ray spectroscopy proximal survey within experimental fields with clayey soils in western Sicily.The γ-ray spectrometer used for the fieldwork was “The Mole”, made by “The Soil Company”, “Medusa system” and the University of Groningen, from The Netherlands. During the survey of eight experimental fields, 55 soil samples were collected for laboratory analysis of particle size distribution, calcium carbonate, organic carbon and total nitrogen content. The results of the work showed the statistical correlations between soil features and γ-ray data. 

Waste reduction by separation of contaminated soils during environmental restoration

International Nuclear Information System (INIS)

Roybal, J.A.; Conway, R.; Galloway, B.; Vinsant, E.; Slavin, P.; Guerin, D.

1998-06-01

During cleanup of contaminated sites, Sandia National Laboratories, New Mexico (SNL/NM) frequently encounters soils with low-level radioactive contamination. The contamination is not uniformly distributed, but occurs within areas of clean soil. Because it is difficult to characterize heterogeneously contaminated soils in detail and to excavate such soils precisely using heavy equipment, it is common for large quantities of uncontaminated soil to be removed during excavation of contaminated sites. This practice results in the commingling and disposal of clean and contaminated material as low-level waste (LLW), or possibly low-level mixed waste (LLMW). Until recently, volume reduction of radioactively contaminated soil depended on manual screening and analysis of samples, which is a costly and impractical approach and does not uphold As Low As Reasonably Achievable (ALARA) principles. To reduce the amount of LLW and LLMW generated during the excavation process, SNL/NM is evaluating two alternative technologies. The first of these, the Segmented Gate System (SGS), is an automated system that located and removes gamma-ray emitting radionuclides from a host matrix (soil, sand, dry sludge). The matrix materials is transported by a conveyor to an analyzer/separation system, which segregates the clean and contaminated material based on radionuclide activity level. The SGS was used to process radioactively contaminated soil from the excavation of the Radioactive Waste Landfill. The second technology, Large Area Gamma Spectroscopy (LAGS), utilizes a gamma spec analyzer suspended over a slab upon which soil is spread out to a uniform depth. A counting period of approximately 30 minutes is used to obtain a full-spectrum analysis for the isotopes of interest. The LAGS is being tested on the soil that is being excavated from the Classified Waste Landfill

Porosity measurement of amorphous materials by gamma ray transmission

International Nuclear Information System (INIS)

Poettker, Walmir Eno

2000-01-01

In this work it is presented the measurement of the total porosity of TRe soil, Sandstone Berea rocks and porous ceramics samples. For the determination of the total porosity, the Arquimedes method (conventional) and the gamma ray transmission methodology were employed. The porosity measurement using the gamma methodology has a significant advantage respect to the conventional method due to the fast and non-destructive determination, and also for supplying results with a greater characterization in small scales, in relation to the heterogeneity of the porosity. The conventional methodology presents good results only for homogeneous samples. The experimental set up for the gamma ray transmission technique consisted of a 241 Am source (59,53 keV), a NaI (Tl) scintillation detector, collimators, a XYZ, micrometric table and standard gamma spectrometry electronics connected to a multichannel analyser. (author)

Determining photon energy absorption parameters for different soil samples

International Nuclear Information System (INIS)

Kucuk, Nil; Cakir, Merve; Tumsavas, Zeynal

2013-01-01

The mass attenuation coefficients (μ s ) for five different soil samples were measured at 661.6, 1173.2 and 1332.5 keV photon energies. The soil samples were separately irradiated with 137 Cs and 60 Co (370 kBq) radioactive point gamma sources. The measurements were made by performing transmission experiments with a 2″ x 2″ NaI(Tl) scintillation detector, which had an energy resolution of 7% at 0.662 MeV for the gamma-rays from the decay of 137 Cs. The effective atomic numbers (Z eff ) and the effective electron densities (N eff ) were determined experimentally and theoretically using the obtained μ s values for the soil samples. Furthermore, the Z eff and N eff values of the soil samples were computed for the total photon interaction cross-sections using theoretical data over a wide energy region ranging from 1 keV to 15 MeV. The experimental values of the soils were found to be in good agreement with the theoretical values. Sandy loam and sandy clay loam soils demonstrated poor photon energy absorption characteristics. However, clay loam and clay soils had good photon energy absorption characteristics. (author)

Distribution Of Natural Radioactivity On Soil Size Particles

International Nuclear Information System (INIS)

Tran Van Luyen; Trinh Hoai Vinh; Thai Khac Dinh

2008-01-01

This report presents a distribution of natural radioactivity on different soil size particles, taken from one soil profile. On the results shows a range from 52% to 66% of natural radioisotopes such as 238 U, 232 Th, 226 Ra and 40 K concentrated on the soil particles below 40 micrometers in diameter size. The remained of natural radioisotopes were distributed on a soil particles with higher diameter size. The study is available for soil sample collected to natural radioactive analyze by gamma and alpha spectrometer methods. (author)

Radionuclide mobility in soils and its effect on the external radiation exposure

International Nuclear Information System (INIS)

Bunzl, K.; Hillmann, U.; Jacob, P.; Kretner, R.; Schimmack, W.; Tikhomirov, F.; Scheglov, A.; Arkhipov, N.P.; Arkhipov, A.N.; Alexakhin, R.M.; Kruglov, S.V.; Loschilov, N.; Ivanov, Y.; Levchuk, S.; Kashparov, V.; Oreshich, L.

1996-01-01

In order to predict the gamma-dose rate of 137 Cs for a period of about 100 years after the Chernobyl accident, the present vertical distribution of radiocesium in several meadow soils in the Chernobyl area and in Germany was determined and the corresponding residence half-times of this radionuclide in the various soil layers were evaluated with a compartment model. The resulting residence half-times were subsequently used to calculate the vertical distribution of 137 Cs in the soil as a function of time and finally to predict the external gamma-dose rates in air for these sites at various times. The results show that the time dependence of the relative gamma-dose rate in air D/D t=0 at both sites can be described by a two-term exponential equation. At a given time, the relative gamma-dose rate at the Chernobyl sites is always higher as compared to the German sites. This difference is the result of the slower vertical migration of 137 Cs at the Chernobyl sites

77 FR 62267 - Proposed Extension of Existing Information Collection; Gamma Radiation Surveys

Science.gov (United States)

2012-10-12

... debilitating occupational diseases. Natural sources include rocks, soils, and ground water. Gamma radiation..., electronic, mechanical, or other technological collection techniques or other forms of information technology...

Isodose mapping of terrestrial gamma radiation dose rate of Selangor state, Kuala Lumpur and Putrajaya, Malaysia

International Nuclear Information System (INIS)

Sanusi, M.S.M.; Ramli, A.T.; Gabdo, H.T.; Garba, N.N.; Heryanshah, A.; Wagiran, H.; Said, M.N.

2014-01-01

A terrestrial gamma radiation survey for the state of Selangor, Kuala Lumpur and Putrajaya was conducted to obtain baseline data for environmental radiological health practices. Based on soil type, geological background and information from airborne survey maps, 95 survey points statistically representing the study area were determined. The measured doses varied according to geological background and soil types. They ranged from 17 nGy h −1 to 500 nGy h −1 . The mean terrestrial gamma dose rate in air above the ground was 182 ± 81 nGy h −1 . This is two times higher than the average dose rate of terrestrial gamma radiation in Malaysia which is 92 nGy h −1 (UNSCEAR 2000). An isodose map was produced to represent exposure rate from natural sources of terrestrial gamma radiation. - Highlights: • A methodology is presented to reduce terrestrial gamma dose rate field survey. • Geological background of acid intrusive of granitic type has the highest dose rates. • The mean dose rate is 2 times higher than the world average. • Isodose map of terrestrial gamma radiation for Selangor, Kuala Lumpur and Putrajaya was produced

Assessment of soil sample quality used for density evaluations through computed tomography

International Nuclear Information System (INIS)

Pires, Luiz F.; Arthur, Robson C.J.; Bacchi, Osny O.S.

2005-01-01

There are several methods to measure soil bulk density (ρ s ) like the paraffin sealed clod (PS), the volumetric ring (VR), the computed tomography (CT), and the neutron-gamma surface gauge (SG). In order to evaluate by a non-destructive way the possible modifications in soil structure caused by sampling for the PS and VR methods of ρ s evaluation we proposed to use the gamma ray CT method. A first generation tomograph was used having a 241 Am source and a 3 in x 3 in NaI(Tl) scintillation crystal detector coupled to a photomultiplier tube. Results confirm the effect of soil sampler devices on the structure of soil samples, and that the compaction caused during sampling causes significant alterations of soil bulk density. Through the use of CT it was possible to determine the level of compaction and to make a detailed analysis of the soil bulk density distribution within the soil sample. (author)

Measurement of activity concentration of primordial radionuclides in the soil samples of Tiruchirappalli, Tamil Nadu, India

International Nuclear Information System (INIS)

Sadiq Bukhari, A.; Saiyad Musthafa, M.; Syed Mohamed, H.E.; Krishnamoorthy, R.; Shahul Hameed, M.M.; Shahul Hameed, P.

2008-01-01

Full text: Radioactive minerals such as uranium ( 238 U), thorium ( 232 Th) and potassium ( 40 K) are considered to be Primordial radionuclides which are widely distributed in the earth's crust. Gamma-radiation from these radionuclides represents the main external source of irradiation for the human body. Human beings are exposed outdoors to the natural terrestrial radiation that originates predominantly from the upper 30 cm of the soil. A pilot project was therefore initiated aiming at systematically measuring the terrestrial gamma radiation in Tiruchirappalli city, Tamil Nadu, South India and to establish baseline data on the terrestrial background radiation level determining its contribution to the annual effective dose equivalent to the human population. The natural radioactivity concentrations were studied in soil samples collected from 50 locations in Tiruchirappalli city. The concentration varies significantly over different soil types and the highest radioactivity was measured over soil types of granite origin followed by red soil and alluvial loam. The mean activity concentrations of 232 Th, 238 U and 40 K in soil samples are found to be 81.78 Bq.kg -1 , 32.62 Bq.kg -1 , and 551.35 Bq.kg -1 respectively. The calculated gamma dose from the soil is in the range between 38.86nGy.h -1 and 240.59 nGy.h -1 with a mean value of 89.76 nGy.h -1 . The mean annual effective dose to the population from outdoor terrestrial gamma radiation was estimated to be 0.11mSv.y -1 which is low as compared with the maximum permissible effective dose equivalent of 1mSv.y -1 (ICRP,1991). In the present study it is observed that the major sources of gamma radiation in soils are mainly derived from rocky area with granite basement. (author)

Soil structure changes evaluated with computed tomography

International Nuclear Information System (INIS)

Pires, Luiz Fernando

2010-01-01

The objective of this work was to evaluate in millimetric scale changes in soil bulk density and porosity, using the gamma-ray computed tomography in soil samples with disturbed structure due to wetting and drying (W-D) cycles. Soil samples with 98.1 cm 3 were sieved using a 2 mm mesh and homogeneously packed in PVC cylinders. Soil samples were submitted to 1, 2, and 3 W-D cycles. Control samples were not submitted to W-D cycles. After repetitions of W-D cycles, soil sample porosity decreased and soil layers became denser. Computed tomography allowed a continuous analysis of soil bulk density and also soil porosity along millimetric (0.08 cm) layers, what cannot be provided by traditional methods used in soil physics. (author)

GAMMA-RAY CHARACTERIZATION OF THE U-SERIES INTERMEDIATE DAUGHTERS FROM SOIL SAMPLES AT THE PENA BLANCA NATURAL ANALOG, CHIHUAHUA, MEXICO

International Nuclear Information System (INIS)

French, D.C.; Anthony, E.Y.; Goodell, P.C.

2005-01-01

The Pena Blanca natural analog is located in the Sierra Pena Blanca, approximately 50 miles north of Chihuahua City, Mexico. The Sierra Pena Blanca is composed mainly of ash-flow tuffs, and the uranium in the region is contained in the brecciated zones of these tuffs. The Pena Blanca site is considered a natural analog to the proposed Yucca Mountain Nuclear Waste Repository because they share similar characteristics of structure, volcanic lithology, tectonic activity, and hydrologic regime. One of the mineralized zones, the Nopal I deposit, was mined in the early 1980s and the ore was stockpiled close to the mine. This stockpile area has subsequently been cleared and is referred to as the prior high-grade stockpile (PHGS) site. Soil surrounding boulders of high-grade ore associated with the PHGS site have been sampled. The purpose of this study is to characterize the transport of uranium series radioisotopes from the boulder to the soil during the past 25 years. Transport is characterized by determining the activities of individual radionuclides and daughter to parent ratios. The daughter to parent ratios are used to establish whether the samples are in secular equilibrium. Activities are determined using gamma-ray spectroscopy. Isotopes of the uranium series decay chain detected by gamma-ray spectroscopy include 210 Pb, 234 U, 234 Th, 230 Th, 226 Ra, 214 Pb, 214 Bi, and 234 Pa. Preliminary results indicate that some daughter to parent pairs appear to be in secular disequilibrium. Thorium is in excess relative to uranium, and radium is in excess relative to thorium. A deficiency appears to exist for 210 Pb relative to 214 Bi and 214 Pb. If these results are borne out by further analysis, they would suggest transport of nuclides from the high-grade boulder into its surroundings, followed by continued leaching of uranium and lead from the environment

Response of soil aggregate stability to storage time of soil samples

International Nuclear Information System (INIS)

Gerzabek, M.H.; Roessner, H.

1993-04-01

The aim of the present study was to investigate the well known phenomenon of changing aggregate stability values as result of soil sample storage. In order to evaluate the impact of soil microbial activity, the soil sample was split into three subsamples. Two samples were sterilized by means of chloroform fumigation and gamma irradiation, respectively. However, the aggregate stability measurements at three different dates were not correlated with the microbial activity (dehydrogenase activity). The moisture content of the aggregate samples seems to be of higher significance. Samples with lower moisture content (range: 0.4 to 1.9%) exhibited higher aggregate stabilities. Thus, airdried aggregate samples without further treatment don't seem to be suitable for standardized stability measurements. (authors)

Problem of cadmium, arsenic and zinc determination in enviroment samples

International Nuclear Information System (INIS)

Malyugin, M.S.; Luzhnova, M.A.; Lontsikh, S.V.

1983-01-01

Using the emission spectroscopy technique new information has been obtained on cadmium-, arsenic and zinc content in some reference samples (RS) of rocks and soils not previously certified as to the content of the elements, as well as in nealy issued RS of soils. Metrologic estimation of the results obtained is carried out. A comparison with the atomic-absorption analysis data as well as with those of the neutron-activation-, colorimetric and other methods of the analysis permits to refer to the advantages of using the spectrographic determination technique based on fractionated evaporation, in case of determining cadmium and arsenic in rocks and soils. Consideration of the results of cadmium, arsenic and zinc spectrography contributed greatly to the certification of reference samples of soils

Radiological impact of a municipal solid waste landfill on soil and groundwater using 2-D resistivity tomography and gamma ray spectroscopy

International Nuclear Information System (INIS)

Ehirim, C.N.; Itota, G.O.

2011-01-01

The radiological impacts of a municipal solid waste landfill on soil and groundwater in Port Harcourt municipality was investigated by integrating 2-D resistivity imaging and gamma-ray spectroscopy. The objective of the study is to determine the lateral and vertical limits of leachate contamination, and to estimate the radioactivity concentrations in soil and groundwater. Results show that the soil and ground water have been contaminated by landfill emissions and radioactive materials throughout the landfill area. The distribution of the contamination is uneven and spotty, both horizontally and vertically, and has penetrated to depths exceeding 31m into the ground water aquifer. The primary contaminants found in the site were leachate, landfill gases, and 40 K, 226 Ra, and 228 Ra radionuclides. The mean absorbed dose rates of 31.98nGy/hr, 10.51nGy/hr and 6.98nGy/hr, and mean dose rate equivalents of 0.28mSv/yr, 0.09mSv/yr and 0.06mSv/yr were obtained for the soil, leachate and water samples, respectively. The mean absorbed and equivalent dose rates in the soil and water samples are greater than their controls, suggesting that the landfill area is contaminated. These results are comparable to those reported for other waste sites in the area and lower than the maximum permitted limits for the general public of 1mSv/yr and 0.1mSv/yr for soil and water, respectively. These therefore, have no immediate radiological health burden on the inhabitants who depend on the soil and groundwater for their crops and potable water supply, except for the effects of disease causing micro-organism and non-methane volatile organic compounds (VOCs) from the leachate. However, with continuous consumption of crop products and intake of groundwater, increase in the activity concentration and dose rates of these radionuclides may occur over time, with adverse effects on humans.

Soil compaction and gamma radiation ({sup 60}Co) in the development of the cowpea beans [Vigna unguiculata, (L) Walp]; Compactacao do solo e radiacao gama ({sup 60}Co) no desenvolvimento do feijao caupi [Vigna unguiculata, (L) Walp

Energy Technology Data Exchange (ETDEWEB)

Viana, Eliane Ferreira; Colaco, Waldeciro [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Radioagronomia]. E-mails: aroucha@ufpe.br; wcolaco@ufpe.br

2005-08-15

The objective is to investigate the effect of compaction and increased doses of gamma radiation on the development of cowpea [Vigna unguiculata, (L) Walp] var. IPA-206 cultivated in a Neossolo fluvic soil, artificially compacted. Significant differences were observed in plant height, with the increase doses in soil density (1.30 Mg.m{sup -3} - compacted soil and 1.70 Mg.m{sup -3} - non-compacted soil), and in response to increased doses of irradiation (y-rays) [ [0, 100, 200 and 300 Gy). The diameter of the stem was significantly reduced in response to the increase in soil density, however the same did not occur in relation to the doses of irradiation (y-rays) holding capacity of the soil was reduced in response to the increase in soil density. (author)

Benchmarking the inelastic neutron scattering soil carbon method

Science.gov (United States)

The herein described inelastic neutron scattering (INS) method of measuring soil carbon was based on a new procedure for extracting the net carbon signal (NCS) from the measured gamma spectra and determination of the average carbon weight percent (AvgCw%) in the upper soil layer (~8 cm). The NCS ext...

Committed dose assessment based on background outdoor gamma exposure in Chihuahua City, Mexico

International Nuclear Information System (INIS)

Luevano G, S.; Perez T, A.; Pinedo A, C.; Renteria V, M.; Carrillo F, J.; Montero C, M. E.

2015-10-01

Full text: Determining ionizing radiation in a geographic area serves to assess its effects on populations health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the committed dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, annual effective dose, and the lifetime cancer risk, 48 sampling points were randomly selected along the Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Muller counter. At the same sites, 48 soil samples were taken to obtain the activity concentrations of 226 Ra, 232 Th, 40 K and their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Outdoor gamma dose rates ranged from 56 to 193 n Gy h -1 . Results indicated that lifetime effective dose to inhabitants of Chihuahua City is in average of 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of activity concentrations in soil were 51.8, 73.1, and 1096.5 Bq kg -1 , of 226 Ra, 232 Th and 40 K, respectively. From the analysis of the spatial distribution of 232 Th, 226 Ra, and 40 K is to north, to north-center, and to south of city, respectively. In conclusion, natural background gamma dose received by inhabitants of Chihuahua City is high and mainly due to geological characteristics of the zone. (Author)

Transmission coefficients of radiation dose equivalents in soil

International Nuclear Information System (INIS)

Simovic, R.; Marinkovic, N.

1993-01-01

In this paper an exponential formula wa proposed for calculating transmission of neutron and secondary gamma radiation through soil slabs. Parameters α and A of the transmission formula are given as rational functions dependent on the percent of water in the soil. Results are compared to those obtained by SABINE-3 code and a satisfactory agreement is shown for soil slab thicknesses for 50 - 500 cm (author) [sr

Natural radioactivity measurements in soil samples from Hamirpur district, Himachal Pradesh, India

International Nuclear Information System (INIS)

Singh, Surinder; Singh, Baldev; Kumar, Ajay

2003-01-01

Radium, thorium and potassium analysis have been made in soil samples collected from some villages of Hamirpur district, Himachal Pradesh, India using gamma ray spectrometry. The work has been undertaken keeping in view the health hazard effects of these radioelements in the environment. The results for radium activity are also compared using track etch technique employing radon alpha method developed by Somogyi (Technical reports series no. 310, vol. 1, IAEA, Vienna, 1990, p. 229). The measurements have been taken using 5''x4'' NaI(Tl) detector. The gamma ray lines of 1.46, 1.76 and 2.62 MeV were employed for potassium, radium and thorium analysis. The results for radium content in soil obtained by gamma ray spectrometry agrees with that determined by the track etch technique. The radium activity in soil samples of Hamirpur district is found to be within the safe limits

Effects of gamma-rays on an indigenous Bacillus isolate

International Nuclear Information System (INIS)

Jong Bor Chyan; Liew Pauline Woan Ying; Ahmad Zainuri Mohd Dzomir; Siti Khadijah Abu Hadin; Nabilahuda Mohd Tumirin

2010-01-01

A preliminary study was carried out with the aim to obtain strong cellulolytic bacteria by ionizing radiation using a 60 Co source. An indigenous cellulolytic Bacillus sp. NMBCC 10023 originally isolated from soil origin was used in the study. The harvested bacterial pellets from overnight growth cultures were exposed to gamma-irradiation with doses ranging from 1 kGy to 40 kGy. The numbers of surviving bacteria on agar plate decreased as the gamma irradiation dose increased. No isolates were recovered after exposure to doses greater than 10 kGy. Based on the cell count using plate count method, the 90 % lethal dose (LD90) of gamma radiation of Bacillus sp. NMBCC 10023 was between 2-4 kGy. (author)

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

International Nuclear Information System (INIS)

Tyler, A.

2004-01-01

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

Instrumental basis utilizing a sodium iodide detector for radioactive soil evaluations for site remediation

International Nuclear Information System (INIS)

Davis, A.I.

1996-07-01

This document provides the design rational for using a 5.08 by 5.08 cm (2 by 2 in.) sodium iodide detector to aid in boundary mapping of the radioactive contaminated soils at the Hanford Site. The detector can provide adequate response to a homogeneously contaminated soil volume of at least 1.22 to 1.52 m in diameter and up to 45.7 cm deep. The gamma activity basis is described by a soil column in a right circular cylinder that is uniformly isotopic. The detection techniques and characteristics are used to define contaminated areas requiring excavation by locating regions where gamma activities exceed cleanup standards. To determine the areas and boundary of contamination, the boundary and adjacent surfaces will be mapped using the detector operated in a windowed gross-gamma mode

Radon in soil gas in Kosovo.

Science.gov (United States)

Kikaj, Dafina; Jeran, Zvonka; Bahtijari, Meleq; Stegnar, Peter

2016-11-01

An assessment of the radiological situation due to exposure to radon and gamma emitting radionuclides was conducted in southern Kosovo. This study deals with sources of radon in soil gas. A long-term study of radon concentrations in the soil gas was carried out using the SSNTDs (CR-39) at 21 different locations in the Sharr-Korabi zone. The detectors were exposed for an extended period of time, including at least three seasonal periods in a year and the sampling locations were chosen with respect to lithology. In order to determine the concentration of the natural radioactive elements 238 U and 226 Ra, as a precursor of 222 Rn, soil samples were collected from each measuring point from a depth of 0.8 m, and measured by gamma spectrometry. The levels (Bq kg -1 ) of naturally occurring radionuclides and levels (kBq m -3 ) of radon in soil gas obtained at a depth 0.8 m of soil were: 21-53 for 226 Ra, 22-160 for 238 U and 0.295-32 for 222 Rn. With respect to lithology, the highest value for 238 U and 226 Ra were found in limestone and the highest value for 222 Rn was found in metamorphic rocks. In addition, the results showed seasonal variations of the measured soil gas radon concentrations with maximum concentration in the spring months. Copyright © 2016 Elsevier Ltd. All rights reserved.

Analysis of the gamma spectra of the uranium, actinium, and thorium decay series

International Nuclear Information System (INIS)

Momeni, M.H.

1981-09-01

This report describes the identification of radionuclides in the uranium, actinium, and thorium series by analysis of gamma spectra in the energy range of 40 to 1400 keV. Energies and absolute efficiencies for each gamma line were measured by means of a high-resolution germanium detector and compared with those in the literature. A gamma spectroscopy method, which utilizes an on-line computer for deconvolution of spectra, search and identification of each line, and estimation of activity for each radionuclide, was used to analyze soil and uranium tailings, and ore

Fixation of Soil Using PEC and Separation of Fixed Soil

Energy Technology Data Exchange (ETDEWEB)

Choi, Yong Suk; Yang, Hee-Man; Lee, Kune Woo; Seo, Bum-Kyoung; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-10-15

Radioactive cesium (Cs-137) is the most apprehensive element due to its long half-lives, high solubility in water, and strong radiation emission in the form of gamma rays. Because the radioactivity is localized within topsoil, soil surface on topsoil should be fixed to prevent the spreading of the contaminated soils by wind and water erosion. Many methods have been developing for soil fixation to remove radioactive contaminants in soil and prevent to diffuse radioactive materials. Various materials have been used as fixatives such as clays, molecular sieves, polymer, and petroleum based products. One of the methods is a soil fixation or solidification using polyelectrolyte. Polyelectrolytes have many ionic groups and form the polyelectrolyte complex (PEC) due to electrostatic interaction of anion and cation in an aqueous solution. polyelectrolyte complex can fix soil particles by flocculation and formation of crust between soil. The method can prevent a spread of radioactive material by floating on a soil surface. The decontamination efficiency of the surface soils reached about 90%, and dust release was effectively suppressed during the removal of surface soils. However it has a problem that the removed soil must separate soil and polymer to treat as the waste. In this study, the fixation of soil by polyelectrolyte complex to suppress the spread of contaminant and the separation method of soil and polymer was investigated. The properties of polyelectrolyte complex solution and the stability of fixed soil by polyelectrolyte complex were investigated. The concentration of salt in the polyelectrolyte complex solution is a very important parameter for the soil fixation.

Car-borne survey of natural background gamma dose rate in Canakkale region (Turkey)

International Nuclear Information System (INIS)

Turhan, S.; Arikan, I. H.; Oquz, F.; Aezdemir, T.; Yuecel, B.; Varinlioqlu, A.; Koese, A.

2012-01-01

Natural background gamma radiation was measured along roads in the environs of Canakkale region by using a car-borne spectrometer system with a plastic gamma radiation detector. In addition, activity concentrations of 238 U, 226 Ra, 232 Th and 40 K in soil samples from the Canakkale region were determined by using a gamma spectrometer with an HPGe detector. A total of 92 856 data of the background gamma dose rate were collected for the Canakkale region. The background gamma dose rate of the Canakkale region was mapped using ArcGIS software, applying the geostatistical inverse distance-weighted method. The average and population-weighted average of the gamma dose are 55.4 and 40.6 nGy h -1 , respectively. The corresponding average annual effective dose to the public ranged from 26.6 to 96.8 μSv. (authors)

Assessment of terrestrial gamma radiation dose rate (TGRD) of Kelantan State, Malaysia. Relationship between the geological formation and soil type to radiation dose rate

International Nuclear Information System (INIS)

Garba, N.N.; Gabdo, H.T.; Federal College of Education, Yola

2014-01-01

Terrestrial gamma radiation dose rates (TGRD) of Kelantan State were measured in situ using a portable [NaI(TI)] micro roentgen (μR) survey meter. The TGRD rates ranged between 44 and 500 nGy h -1 with a mean value of 209 ± 8 nGy h -1 . The distribution of these measurements in various districts of the state shows the statistically the influence of geology and soil types on the dose rate values. The data obtained could be used in formulating safety standard and radiological guidelines. (author)

Temporal reduction of the external gamma dose rate due to 137Cs mobility in sandy beaches

International Nuclear Information System (INIS)

Rizzotto, M.; Toso, J.; Velasco, H.; Belli, M.; Sansone, U.

2009-01-01

In the present paper the contribution to the external gamma dose rate due o 137 Cs in soil as a function of time is presented. Sampling sites were elected along the Calabria and Basilicata Regions coastal beaches (southern art of Italy) to assess the external gamma dose rate in air, 1 m above the round level. A convection-dispersion model, with constant parameters was sed to approximate the radiocesium soil vertical migration. The model was calibrated using the initial 137 Cs activity deposition in this region Chernobyl fallout) and 137 Cs activity concentration down the soil profile, measured 10 years later. The dispersion coefficient and the advection velocity values, were respectively: 2.17 cm 2 y -1 and 0.32 cm -1 . The Radionuclide Software Package (RSP), which uses a Monte Carlo simulation code, was used to determine the primary 137 Cs gamma dose contribution in air 1 m above the ground surface. The resulting 137 Cs external dose rate ranged from 0.42 nGy h -1 in 1986, to 0.05 nGy h -1 in 007. (author)

Effect of Gamma Rays and Salinity on Growth and Chemical Composition of Ambrosia maritima L. Plant

International Nuclear Information System (INIS)

Moemen, A.M.E.

2012-01-01

This work achieved to study the effects of, mixture of salt 2:2:1 (Na Cl-CaCl 2 and Mg SO 4 ), concentration of (0, 2000, 4000 and 6000 ppm). on growth characters, some chemical components and some active ingredients in shoots of Ambrosia maritima plants, at different stages of growth, during two seasons. Pots 30 cm in diameter were filled of sand-loamy soils in appropriate concentration, all pots were irrigated with tap water. The exposed damsisa seeds to gamma rays, doses (0, 20, 40, and 80 Gy) before sowing together with control non irradiated seeds were sown in saline soils (0, 2000, 4000 and 6000 ppm). Soil salinity treatments caused a decrease in plant height, number of leaves, content of damsin, and an increase in fresh weigh, dry weight, total sugars, total chlorophyll, amino acids and ambrosine content. Also, Gamma rays caused an increase in most of growth parameters and most of chemical composition. It was observed that 40 or 80 Gy was more effective. We investigated the combined effect of levels of salinity and doses of radiation used, this interference improve growth parameters and chemical composition in ambrosia maritima plants and caused ascertain the role of gamma irradiation in plants tolerance to soil salinity and alleviation their harmful effect on plants.

Investigation of soil radioactivity of Alkhwai area central Sudan

International Nuclear Information System (INIS)

Mohammed, R. H. A.

2012-10-01

The present study is the first of its type to be conducted in Alkhwai area aiming at thorough investigation of natural environmental radioactivity. Considerable variation in soil radioactivity with location is observed. Results show that the average concentrations of 2 38U , 2 32T h and 4 0K in soil were found to be 14.79± 2.43, 20.71± 3.59 and 162.09± 21.19 respectively and have the range 10.0-21.98, 13.89-28.55 and from 113.51 to 219.45 respectively. It is observed that there is strong correlation between Uranium-Thorium and fair correlation between Uranium-Potassium and Thorium-Potassium. The average value of calculated gamma radiation dose rate in Alkhwai district was estimated to be (26.10) n Gy h -1 comparable with the world average (59 n Gy/h). The average dose from gamma radiation dose rate to an individual assuming a tropical rural setting is estimated to be 32.03 μSv/year, which is considered to be within the normal range for doses from natural sources. Further measurements of ambient dose for more soil type at different geological features of Sudan are needed to establish a more comprehensive database on the relationship between gamma radiation dose and geological-soil information. (Author)

Radioactivity in Soil Samples Collected in Southern Serbia

International Nuclear Information System (INIS)

Jankovic, M.; Nikolic, J.; Pantelic, G.; Rajacic, M.; Sarap, N.; Todorovic, D.

2013-01-01

In the attack on the Federal Republic of Yugoslavia (the focus effect was of Kosovo and Metohija and southern Serbia) in 1999, NATO forces used ammunition containing depleted uranium. Cleaning action of depleted uranium was performed by Radiation and Environmental Protection Department of the Vinca Institute of Nuclear Science, during 2002?2007 at locations: Pljackovica, Bratoselce, Borovac and Reljan. At all locations underwent detailed dosimetric screening and decontamination was performed. Because of the loose soil, DU projectils were found to a depth of 1 m. Found missiles, contaminated soil and radioactive material has been collected and stored on radioactive waste. After cleaning the ground is leveled and another dosimetric prospecting was performed. Monitoring of radioactivity in southern Serbia included determination of gamma emitters as well as determination of gross alpha and beta activities in soil, water and plant. Sampling was carried out at Pljackovica, Borovac, Bratoselce and Reljan in July 2011. This paper presents only the results of measurement of gamma emitters in soil samples and showed the presence of natural radionuclides: 226Ra, 232Th, 40K, 235U, 238U and the produced radionuclide 137Cs (from the Chernobyl accident). Also, the ratio between the 235U and 238U is given. In order to evaluate the radiological hazard of the natural radioactivity, the radium equivalent activity, the gamma-absorbed dose rate and the external hazard index have been calculated. (author)

Committed dose assessment based on background outdoor gamma exposure in Chihuahua City, Mexico

Energy Technology Data Exchange (ETDEWEB)

Luevano G, S.; Perez T, A.; Pinedo A, C.; Renteria V, M. [Universidad Autonoma de Chihuahua, Facultad de Zootecnia y Ecologia, Perif. Francisco R. Almada Km 1, 31415 Chihuahua, Chih. (Mexico); Carrillo F, J.; Montero C, M. E., E-mail: mrenteria@uach.mx [Centro de Investigacion en Materiales Avanzados, Miguel de Cervantes 120, 31136 Chihuahua, Chih. (Mexico)

2015-10-15

Full text: Determining ionizing radiation in a geographic area serves to assess its effects on populations health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the committed dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, annual effective dose, and the lifetime cancer risk, 48 sampling points were randomly selected along the Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Muller counter. At the same sites, 48 soil samples were taken to obtain the activity concentrations of {sup 226}Ra, {sup 232}Th, {sup 40}K and their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Outdoor gamma dose rates ranged from 56 to 193 n Gy h{sup -1}. Results indicated that lifetime effective dose to inhabitants of Chihuahua City is in average of 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of activity concentrations in soil were 51.8, 73.1, and 1096.5 Bq kg{sup -1}, of {sup 226}Ra, {sup 232}Th and {sup 40}K, respectively. From the analysis of the spatial distribution of {sup 232}Th, {sup 226}Ra, and {sup 40}K is to north, to north-center, and to south of city, respectively. In conclusion, natural background gamma dose received by inhabitants of Chihuahua City is high and mainly due to geological characteristics of the zone. (Author)

A generalized transmission method for gamma-efficiency determinations in soil samples

International Nuclear Information System (INIS)

Bolivar, J.P.; Garcia-Tenorio, R.; Garcia-Leon, M.

1994-01-01

In this paper, a generalization of the γ-ray transmission method which is useful for measurements on soil samples, for example, is presented. The correction factor, f, is given, which is a function of the apparent density of the soil and the γ-ray energy. With this method, the need for individual determinations of f, for each energy and apparent soil density is avoided. Although the method has been developed for soils, the general philosophy can be applied to other sample matrices, such as water or vegetables for example. (author)

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

International Nuclear Information System (INIS)

Fueloep, M.

2000-01-01

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

Soil biological shield exposed to high energy neutrons; Zemlja kao bioloski stit od neutrona visokih energija

Energy Technology Data Exchange (ETDEWEB)

Simovic, R; Marinkovic, N [Institute of nuclear sciences Vinca, Belgrade (Yugoslavia)

1993-04-15

Shielding efficiency of soil biological shield exposed to high energy neutrons was investigated. Dose rate equivalents for neutrons, secondary gamma and gamma radiation were computed on the surface of soil slabs having different thicknesses. Yields of primary and secondary nuclear radiation in the total dose were evaluated. Influence of the incident neutron spectrum, water content and chemical composition of the material on its shielding efficiency was examined. It was found that the soil density and the water content determine the quality of biological shield, the influence of other factors being less important. Comparison of shielding efficiencies for soil with sand, brick and ordinary concrete shields was done.

Study of 137Cs redistribution in semi-arid land of western Algeria for soil loss assessment

Directory of Open Access Journals (Sweden)

Ahmed Azbouche

2017-06-01

Full Text Available Abstract: Soil erosion is a global environmental problem, and anthropogenic fallout radionuclides offer a promising tool for describing and quantifying soil redistribution on decadal time scales. The 137Cs technique for investigating rates and patterns of soil erosion has now been successfully applied in a wide range of environments. This radionuclide strongly adheres to soil particles and therefore can be used as a tracer in soil movement studies. In this work we present the 137Cs redistribution in an agricultural area, to assess the soil erosion and sedimentation zones. 36 samples were collected in small watershed called Sidi Mohamed Cherif at Oued Isser located in North West of Algeria. The preparation of soil samples required drying, crushing and sieving to finally lower than 2mm diameter. The sample analysis was analyzed by gamma spectrometry technique composed with a high resolution HPGe semi-conductor detector with 1.8 keV to 60Co 1332.5 keV line, after soil characterization with WDXRF. The spectrums treatment was carried out using the Genie 2000 software dedicated to the processing of gamma spectra. The specific activity of 137Cs is obtained variable from 0.25Bq kg-1 and 7.8 Bq kg-1. These results allow determining the erosion global erosion rate, is about 12.5 t ha?1 yr?1. Keywords: 137Cs, Soil Characterization, Soil erosion, Gamma spectrometry, North West of Algeria.

The exposure of the Greek population to natural gamma radiation of terrestrial origin

International Nuclear Information System (INIS)

Probonas, M.; Kritidis, P.

1993-01-01

The terrestrial natural radioactivity is a significant source of exposure of the population to ionising radiations. To evaluate the external doses received by the Greek population due to this source, soil samples from all Greek provinces have been collected and analysed using two high resolution gamma spectroscopy devices with germanium detectors of high purity (HPGe detectors). The concentrations of 238 U, 226 Ra, 228 Ra, 228 Th and 40 K show significant variations, which correlate with the chemical consistency of soils from region to region. A theoretical evaluation of the dose equivalent rates due to the external natural gamma radiation of terrestrial origin has been made. The mean value does not differ greatly from the average dose rates in other countries of the world. (Author)

Optimisation of beryllium-7 gamma analysis following BCR sequential extraction

Energy Technology Data Exchange (ETDEWEB)

Taylor, A. [Plymouth University, School of Geography, Earth and Environmental Sciences, 8 Kirkby Place, Plymouth PL4 8AA (United Kingdom); Blake, W.H., E-mail: wblake@plymouth.ac.uk [Plymouth University, School of Geography, Earth and Environmental Sciences, 8 Kirkby Place, Plymouth PL4 8AA (United Kingdom); Keith-Roach, M.J. [Plymouth University, School of Geography, Earth and Environmental Sciences, 8 Kirkby Place, Plymouth PL4 8AA (United Kingdom); Kemakta Konsult, Stockholm (Sweden)

2012-03-30

Graphical abstract: Showing decrease in analytical uncertainty using the optimal (combined preconcentrated sample extract) method. nv (no value) where extract activities were soil to underpin the assumption of irreversible adsorption. Sequential extractions offer a readily accessible means of determining the associations of {sup 7}Be with operationally defined soil phases. However, the subdivision of the low activity concentrations of fallout {sup 7}Be in soils into geochemical fractions can introduce high gamma counting uncertainties. Extending analysis time significantly is not always an option for batches of samples, owing to the on-going decay of {sup 7}Be (t{sub 1/2} = 53.3 days). Here, three different methods of preparing and quantifying {sup 7}Be extracted using the optimised BCR three-step scheme have been evaluated and compared with a focus on reducing analytical uncertainties. The optimal method involved carrying out the BCR extraction in triplicate, sub-sampling each set of triplicates for stable Be analysis before combining each set and coprecipitating the {sup 7}Be with metal oxyhydroxides to produce a thin source for gamma analysis. This method was applied to BCR extractions of natural {sup 7}Be in four agricultural soils. The approach gave good counting statistics from a 24 h analysis period ({approx}10% (2

Gamma-ray measurements in uppermost soil profile of a grazing area around Londrina city, Parana State, Brazil

International Nuclear Information System (INIS)

Bastos, Rodrigo O.; Andrello, Avacir C.; Appoloni, Carlos R.

2005-01-01

Using high-resolution .-ray spectrometry, soil profiles were measured to assess the depth distribution of 232 Th, 238 U, 226 Ra, 40 K and 137 Cs. The surveyed soil is the Latossolo Vermelho Distroferrico, clayey texture, in a soft wave relief area used for grazing, near Londrina city, Parana, Brazil. Knowledge of radioelement depth distributions is important to understand their behavior along soil history, and in the same time, give clues about it, from pedogenesis to more recent events, such as weathering, erosion or interaction with biosphere. Five points were sampled, three of them in increment depths of 0 to 5 cm, 5 to 10 cm, 10 to 15 cm, 15 to 20 cm, 20 to 35 cm, and for two of them the increment 35-50 cm was collected either. These totalized 27 samples, each of them dried in open air during 48 hours, sieved through 2 mm mesh, sealed in 1-litre plastic Marinelli beakers, and measured in the laboratory. It was employed a standard gamma ray spectrometry electronic chain, with a 66% relative efficiency HPGe detector. Measurement of the efficiency in the range from 60 to 1800 keV was carried out with certified IAEA 375 soil sample. From the measured γ-ray spectra, activity concentrations were determined for 232 Th (from 15.4 to 25.1 Bq kg -1 ), 238 U (from 11.0 to 18.9 Bq kg -1 ), 226 Ra (from 4.0 to 10.9 Bq kg -1 ), 40 K (from 36.0 to 133.9 Bq kg -1 ) and 137 Cs (from 0.0 to 2.2 Bq kg -1 ). Average values and respective deviations are 21.0 ± 2.6 Bq kg -1 for 232 Th, 13.8 ± 1.7 Bq kg -1 for 238 U, 7.8 ± 1.9 Bq kg -1 for 226 Ra, 72.8 ± 30.5 Bq kg -1 for 40 K, and 0.8 ± 0.8 Bq kg -1 for 137 Cs. Depth distributions of each radioelement are presented and possible relations among activities are analyzed (author)

Terrestrial gamma dose rate in Pahang state Malaysia

International Nuclear Information System (INIS)

Gabdo, H.T.; Federal College of Education, Yola; Ramli, A.T.; Sanusi, M.S.; Saleh, M.A.; Garba, N.N.; Ahmadu Bello University, Zaria

2014-01-01

Environmental terrestrial gamma radiations (TGR) were measured in Pahang state Malaysia between January and April 2013. The TGR dose rates ranged from 26 to 750 nGy h -1 . The measurements were done based on geology and soil types of the area. The mean TGR dose rate was found to be 176 ± 5 nGy h -1 . Few areas of relatively enhanced activity were located in Raub, Temerloh, Bentong and Rompin districts. These areas have external gamma dose rates of between 500 and 750 nGy h -1 . An Isodose map of the state was produced using ArcGIS9 software version 9.3. To evaluate the radiological hazard due to terrestrial gamma dose, the annual effective dose equivalent and the mean population weighted dose rate were calculated and found to be 0.22 mSv year -1 and 168 nGy h -1 respectively. (author)

Radionuclide content determination in the soil and 210Pb content in the leaves in Novi Sad parks

International Nuclear Information System (INIS)

Forkapic, S.; Bikit, I.; Mrdja, D.; Todorovic, N.; Krmar, M.; Slivka, J.; Veskovic, M.; Forkapic, S.)

2007-01-01

During the 2005 and 2006 low-level gamma spectrometry measurements of leaves and soil samples from the three greatest city parks were performed on Department of Physics, Faculty of Sciences in Novi Sad. Very susceptible gamma spectrometry method was developed for 210 Pb content determination in the samples of fallen leaves. In order to control radioactivity of soil and transfer of radionuclides to plants, the activity concentrations of radionuclides in the soil were determined by means of two ultra high resolute HPGe detectors [sr

Comparison of laser fluorimetry, high resolution gamma-ray spectrometry and neutron activation analysis techniques for determination of uranium content in soil samples

International Nuclear Information System (INIS)

Ghods, A.; Asgharizadeh, F.; Salimi, B.; Abbasi, A.

2004-01-01

Much more concern is given nowadays for exposure of the world population to natural radiation especially to uranium since 57% of that exposure is due to radon-222, which is a member of uranium decay series. Most of the methods used for uranium determination is low concentration require either tedious separation and preconcentration or the accessibility to special instrumentation for detection of uranium at this low level. this study compares three techniques and methods for uranium analysis among different soil sample with variable uranium contents. Two of these techniques, neutron activation analysis and high resolution gamma-ray spectrometry , are non-destructive while the other, laser fluorimetry is done via chemical extraction of uranium. Analysis of standard materials is done also to control the quality and accuracy of the work. In spite of having quite variable ranges of detection limit, results obtained by high resolution gamma-ray spectrometry based on the assumption of having secular equilibrium between uranium and its daughters, which causes deviation whenever this condition was missed. For samples with reasonable uranium content, neutron activation analysis would be a rapid and reliable technique, while for low uranium content laser fluorimetry would be the most appropriate and accurate technique

The Northern Marshall Islands radiological survey: A quality control program for radiochemical and gamma spectroscopy analysis

International Nuclear Information System (INIS)

Kehl, S.R.; Mount, M.E.; Robison, W.L.

1995-09-01

From 1979 to 1989, approximately 25,000 Post Northern Marshall Islands Radiological Survey (PNMIRS) samples were collected, and over 71,400 radiochemical and gamma spectroscopy analyses were performed to establish the concentration of 90 Sr, 137 Cs, 241 Am, and plutonium isotopes in soil, vegetation, fish, and animals in the Northern Marshall Islands. While the Low Level Gamma Counting Facility (B379) in the Health and Ecological Assessment (HEA) division accounted for over 80% of all gamma spectroscopy analyses, approximately 4889 radiochemical and 5437 gamma spectroscopy analyses were performed on 4784 samples of soil, vegetation, terrestrial animal, and marine organisms by outside laboratories. Four laboratories were used by Lawrence Livermore National Laboratory (LLNL) to perform the radiochemical analyses: Thermo Analytical Norcal, Richmond, California (TMA); Nuclear Energy Services, North Carolina State University (NCSU); Laboratory of Radiation Ecology, University of Washington (LRE); and Health and Ecological Assessment (HEA) division, LLNL, Livermore, California. Additionally, LRE and NCSU were used to perform gamma spectroscopy analyses. The analytical precision and accuracy were monitored by including blind duplicates and natural matrix standards in each group of samples analyzed. On the basis of reported analytical values for duplicates and standards, 88% of the gamma and 87% of the radiochemical analyses in this survey were accepted. By laboratory, 93% of the radiochemical analyses by TMA; 88% of the gamma-ray spectrometry and 100% of the radiochemistry analyses by NCSU; 89% of the gamma spectroscopy and 87% of the radiochemistry analyses by LRE; and 90% of the radiochemistry analyses performed by HEA's radiochemistry department were accepted

Radioactivity measurement of radioactive contaminated soil by using a fiber-optic radiation sensor

Science.gov (United States)

Joo, Hanyoung; Kim, Rinah; Moon, Joo Hyun

2016-06-01

A fiber-optic radiation sensor (FORS) was developed to measure the gamma radiation from radioactive contaminated soil. The FORS was fabricated using an inorganic scintillator (Lu,Y)2SiO5:Ce (LYSO:Ce), a mixture of epoxy resin and hardener, aluminum foil, and a plastic optical fiber. Before its real application, the FORS was tested to determine if it performed adequately. The test result showed that the measurements by the FORS adequately followed the theoretically estimated values. Then, the FORS was applied to measure the gamma radiation from radioactive contaminated soil. For comparison, a commercial radiation detector was also applied to measure the same soil samples. The measurement data were analyzed by using a statistical parameter, the critical level to determine if net radioactivity statistically different from background was present in the soil sample. The analysis showed that the soil sample had radioactivity distinguishable from background.

Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico

Directory of Open Access Journals (Sweden)

Sergio Luevano-Gurrola

2015-09-01

Full Text Available Determining ionizing radiation in a geographic area serves to assess its effects on a population’s health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h−1. At the same sites, 48 soil samples were taken to obtain the activity concentrations of 226Ra, 232Th and 40K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h−1. Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg−1, for 226Ra, 232Th and 40K, respectively. From the analysis, the spatial distribution of 232Th, 226Ra and 40K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize.

Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico.

Science.gov (United States)

Luevano-Gurrola, Sergio; Perez-Tapia, Angelica; Pinedo-Alvarez, Carmelo; Carrillo-Flores, Jorge; Montero-Cabrera, Maria Elena; Renteria-Villalobos, Marusia

2015-09-30

Determining ionizing radiation in a geographic area serves to assess its effects on a population's health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h(-1). At the same sites, 48 soil samples were taken to obtain the activity concentrations of (226)Ra, (232)Th and (40)K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h(-1). Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg(-1), for (226)Ra, (232)Th and (40)K, respectively. From the analysis, the spatial distribution of (232)Th, (226)Ra and (40)K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize.

Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico

Science.gov (United States)

Luevano-Gurrola, Sergio; Perez-Tapia, Angelica; Pinedo-Alvarez, Carmelo; Carrillo-Flores, Jorge; Montero-Cabrera, Maria Elena; Renteria-Villalobos, Marusia

2015-01-01

Determining ionizing radiation in a geographic area serves to assess its effects on a population’s health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h−1. At the same sites, 48 soil samples were taken to obtain the activity concentrations of 226Ra, 232Th and 40K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h−1. Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg−1, for 226Ra, 232Th and 40K, respectively. From the analysis, the spatial distribution of 232Th, 226Ra and 40K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize. PMID:26437425

GAMMA-RAY CHARACTERIZATION OF THE U-SERIES INTERMEDIATE DAUGHTERS FROM SOIL SAMPLES AT THE PENA BLANCA NATURAL ANALOG, CHIHUAHUA, MEXICO

Energy Technology Data Exchange (ETDEWEB)

D.C. French; E.Y. Anthony; P.C. Goodell

2005-07-18

The Pena Blanca natural analog is located in the Sierra Pena Blanca, approximately 50 miles north of Chihuahua City, Mexico. The Sierra Pena Blanca is composed mainly of ash-flow tuffs, and the uranium in the region is contained in the brecciated zones of these tuffs. The Pena Blanca site is considered a natural analog to the proposed Yucca Mountain Nuclear Waste Repository because they share similar characteristics of structure, volcanic lithology, tectonic activity, and hydrologic regime. One of the mineralized zones, the Nopal I deposit, was mined in the early 1980s and the ore was stockpiled close to the mine. This stockpile area has subsequently been cleared and is referred to as the prior high-grade stockpile (PHGS) site. Soil surrounding boulders of high-grade ore associated with the PHGS site have been sampled. The purpose of this study is to characterize the transport of uranium series radioisotopes from the boulder to the soil during the past 25 years. Transport is characterized by determining the activities of individual radionuclides and daughter to parent ratios. The daughter to parent ratios are used to establish whether the samples are in secular equilibrium. Activities are determined using gamma-ray spectroscopy. Isotopes of the uranium series decay chain detected by gamma-ray spectroscopy include {sup 210}Pb, {sup 234}U, {sup 234}Th, {sup 230}Th, {sup 226}Ra, {sup 214}Pb, {sup 214}Bi, and {sup 234}Pa. Preliminary results indicate that some daughter to parent pairs appear to be in secular disequilibrium. Thorium is in excess relative to uranium, and radium is in excess relative to thorium. A deficiency appears to exist for {sup 210}Pb relative to {sup 214}Bi and {sup 214}Pb. If these results are borne out by further analysis, they would suggest transport of nuclides from the high-grade boulder into its surroundings, followed by continued leaching of uranium and lead from the environment.

Introduction to nuclear techniques in agronomy and plant biology

International Nuclear Information System (INIS)

Vose, P.B.

1980-01-01

A scientific textbook concerning the use of nuclear techniques in agricultural and biological studies has been written. In the early chapters, basic radiation physics principles are described including the nature of isotopes and radiation, nuclear reactions, working with radioisotopes, detection systems and instrumentation, radioassay and tracer techniques. The remaining chapters describe the applications of various nuclear techniques including activation analysis for biological samples, X-ray fluorescence spectrography for plants and soils, autoradiography, isotopes in soils studies, isotopic tracers in field experimentation, nuclear techniques in plant function and soil water studies and radiation-induced mutations in plant breeding. The principles and methods of these nuclear techniques are described in a straightforward manner together with details of many possible agricultural and biological studies which students could perform. (U.K.)

[The restoration of the enzyme activity of chernozem soil after gamma-irradiation].

Science.gov (United States)

Denisova, T V; Kazeev, K Sh

2006-01-01

The Influence of gamma-radiation by dozes 1, 5, 10 and 20 kGy on enzyme activity of ordinary chemozem were studied. Dynamics of the restoration of the enzyme activity after the influence of gamma-radiation in model experiments in 3, 30, 90 and 180 days was investigated. The doze 1 kGy did no statistically significant influence on the investigated enzymes. Dehydrogenase is more radiosensitive enzyme than catalase. Values of the saccharase activity differed a significant variation so in most cases it has not been registered statistically significant changes. In 90-180 days of the incubation enzymes activity was restored up to control values. Dehydrogenase activity in 180 days in variants with dozes 10 and 20 kGy was restored up to a level of the control, over variants with dozes 1 and 5 kGy--is higher than the control over 78% and 23% accordingly. Saccharase activity in 180 days after the influence of gamma-radiation with a doze 20 kGy was on 61% lower than the control.

Body composition to climate change studies - the many facets of neutron induced prompt gamma-ray analysis

International Nuclear Information System (INIS)

Mitra, S.

2008-01-01

In-vivo body composition analysis of humans and animals and in-situ analysis of soil using fast neutron inelastic scattering and thermal neutron capture induced prompt-gamma rays have been described. By measuring carbon (C), nitrogen (N) and oxygen (O), protein, fat and water are determined. C determination in soil has become important for understanding below ground carbon sequestration process in the light of climate change studies. Various neutron sources ranging from radio isotopic to compact 14 MeV neutron generators employing the associated particle neutron time-of-flight technique or micro-second pulsing were implemented. Gamma spectroscopy using recently developed digital multi-channel analyzers has also been described

Body composition to climate change studies - the many facets of neutron induced prompt gamma-ray analysis

Energy Technology Data Exchange (ETDEWEB)

Mitra,S.

2008-11-17

In-vivo body composition analysis of humans and animals and in-situ analysis of soil using fast neutron inelastic scattering and thermal neutron capture induced prompt-gamma rays have been described. By measuring carbon (C), nitrogen (N) and oxygen (O), protein, fat and water are determined. C determination in soil has become important for understanding below ground carbon sequestration process in the light of climate change studies. Various neutron sources ranging from radio isotopic to compact 14 MeV neutron generators employing the associated particle neutron time-of-flight technique or micro-second pulsing were implemented. Gamma spectroscopy using recently developed digital multi-channel analyzers has also been described.

Gamma-ray and electrical resistivity measurements in soil with application of carbonatite and agricultural fertilizers in Distrito Federal; Radiacao gama e resistividade eletrica em solo com aplicacao de carbonatito e fertilizantes agricolas no Distrito Federal

Energy Technology Data Exchange (ETDEWEB)

Nascimento, Carlos Tadeu Carvalho do; Gaspar, Jose Carlos; Pires, Augusto Cesar Bittencourt, E-mail: carlostadeu@unb.br, E-mail: gasp@unb.br, E-mail: acbpires@unb.br [Instituto de Geociencias, Universidade de Brasilia, DF (Brazil); Ferreira, Francisco Jose Fonseca, E-mail: francisco.ferreira@ufpr.br [Departamento de Geologia, Universidade Federal do Parana, Curitiba, PR (Brazil); Andrade, Leide Rovenia Miranda de, E-mail: leide@cpac.embrapa.br [Empresa Brasileira de Pesquisa Agropecuaria, Centro de Pesquisa Agropecuaria dos Cerrados, Planaltina, DF (Brazil)

2008-01-15

EMBRAPA (Empresa Brasileira de Pesquisa Agropecuaria) and Brasilia University developed a research project about the viability of carbonatite rock as agricultural fertilizer. As an initial experiment, several mixtures of carbonatite, limestone, phosphorous and potassium compounds were added as fertilizers in an oxisol area (red-latosol, according with Brazilian System of Soil Classification), in Distrito Federal, central Brazil. The experiment area was divided in 56 plots (4 x 7m) and each plot received a fertilizer mixture. The purpose of this work was to verify if the addition of fertilizer mixture to the soil modified its radiometric and resistivity properties and if it is possible to identify this change. Gamma-ray and electrical resistivity measurements were obtained in an experimental area and in a natural savannah type vegetation area. The results showed that the fertilizer addition modified soil natural properties causing a small increase in K, U, Th levels and decreasing ten times electrical resistivity. A low contrast of radiation was observed between plots, and then it was not possible to differentiate the several treatments in base of gamma-ray measurements. Electrical resistivity was efficient to identify three groups of plots related to mixtures characteristics, respectively with phosphorous, potassium and limestone / carbonatite predominance. (author)

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

International Nuclear Information System (INIS)

Miller, K.M.; Shebell, P.

1993-10-01

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

Measurement of radiation levels in soil samples by γ-ray spectrometry

International Nuclear Information System (INIS)

Sontakke, C.V.; Thamke, A.N.; Devika, K.; Srikanth, S.; Jayachandran, N.; Chander, Harish

2016-01-01

The natural terrestrial gamma radiation dose rate is an important contribution to the average dose rate received by the world's population. Estimation of the radiation dose distribution is important in assessing the health risk to a population and serve as the reference in documenting changes to environmental radioactivity in soil due to anthropogenic activities. Human beings are exposed outdoors to the natural terrestrial radiation that originates predominantly from the upper 30 cm of the soil. Only radionuclides with half-lives comparable with the age of the earth or their corresponding decay products existing in terrestrial material such as 238 U, 232 Th and 40 K are of great interest. Since these radionuclides are not uniformly distributed, the knowledge of their distribution in soil and rock play an important role in radiation protection and measurement. Gamma radiation from these represents the main external source of irradiation to the human body and the concentrations of these radionuclides in soil are determined by the radioactivity of the rock and also nature of the process of the formation of the soils. Therefore, radionuclides in soil generate a significant component of the background radiation exposure to the population

Radon emanation from soils

International Nuclear Information System (INIS)

Markkanen, M.; Arvela, H.

1992-01-01

The results of gamma spectrometric sample measurements of radon ( 222 Rn) emanation coefficients and radium concentrations ( 226 Ra) from about 800 Finnish soil samples are presented. The radon emanation rate was measured in about 400 soil samples, using radon-tight cans and Lucas cells. The effects of water content and temperature on radon emanation were investigated, using various samples of different soil types. Radon emanation and the effect of water content on radon emanation were investigated separately for different grain sizes (samples of till). The results provide some information on radon emanation in different soil types and relate emanation in laboratory conditions to conditions in ground soil. In routine measurements of radon emanation from soil samples, use of a 5% water content was considered advisable. The correction coefficients of radon emanation varied between 0.3 and 1.5, depending on the water content and soil type. At 5% water content, hardly any difference was found between radon emanation at temperatures of 20 and 1 o C. Radon emanation was found to be an inverse function of grain sizes larger than 0.5 mm in diameter. (author)

The Utilization of Background Spectrum to Calibrate Gamma Spectrometry

International Nuclear Information System (INIS)

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

2004-01-01

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

Detecting buried radium contamination using soil-gas and surface-flux radon meaurements

International Nuclear Information System (INIS)

Karp, K.E.

1988-06-01

The Technical Measurements Center (TMC) has investigated the effectiveness of using radon soil-gas under surface-flux measurments to locate radium contamination that is buried sufficiently deep to be undetectable by surface gamma methods. At the first test site studied, an indication of a buried source was revealed by mapping anomalous surface-flux and soil-gas concentrations in the near surface overburden. The mapped radon anomalies were found to correspond in rough outline to the shape of the areal extent of the deposit as determined by borehole gamma-ray logs. The 5.9pCi/g radium deposit, buried 2 feet below the surface, went undetected by conventional surface gamma measurements. Similar results were obtained at the second test site where radon and conventional surface gamma measurements were taken in an area having radium concentrations ranging from 13.3 to 341.0 pCi/g at a depth of 4 feet below the surface. The radon methods were found to have a detection limit for buried radium lower than that of the surface gamma methods, as evidenced by the discovery of the 13.3 pCi/g deposit which went undetected by the surface gamma methods. 15 refs., 33 figs., 8 tabs

Study on natural radioactive elements in soil and rock samples around Mandya district, India

International Nuclear Information System (INIS)

Shivakumara, B.C.; Paramesh, L.; Shashikumar, T.S.; Chandrashekara, M.S.

2012-01-01

The soil is a complex mixture of different compounds and rocks. In the natural environment, it is an important source of exposure to radiation due to naturally occurring, gamma emitting radionuclides which include 226 Ra, 232 Th and 40 K present in the soil. The study of distribution of these radionuclides in soil and rock is of great importance for radiation protection and measurements. The activity concentrations of 226 Ra, 232 Th, and 40 K in soil and rock samples collected in Mandya District, Karnataka state, India have been measured by gamma ray spectrometry. The average activity concentrations of 226 Ra, 232 Th, and 40 K (Bq/kg) are found to be 40.2, 62.3, and 317.5 Bq/kg, respectively, in soil samples and 30.5, 34.4, and 700.2 Bq/kg, respectively, in rock samples. The concentrations of radionuclides in soil samples are found to higher than in rock samples. The concentrations of radionuclides in soil and rock samples in the study area are slightly higher than Indian average and world average values. (author)

A new method for studying the transport of gamma photons in various geological materials by combining the SSNTD technique with Monte Carlo simulations

International Nuclear Information System (INIS)

Misdaq, M.A.; Merzouki, A.; Bourzik, W.; Sfairi, T.

2000-01-01

The gamma dose rate due to the uranium and thorium series as well as the potassium 40 nuclei represents a large fraction of the total dose rate from the natural background. Natural gamma-activities of rock and soil samples collected from volcanic areas have been determined using gamma-ray spectrometry. The corresponding gamma dose rates in air have been measured by means of thermoluminescence (TL) dosimeters. Annual absorbed gamma dose rates have been evaluated in different soil samples belonging to an archaeological site by using experimental and calculational methods. Uranium and thorium contents in different geological samples have been determined by using CR-39 and LR-115 type II solid state nuclear track detectors (SSNTD) and calculating the probabilities for alpha particles emitted by the uranium and thorium series to reach and be registered on the SSNTD films. A new method has been developed based on calculating the self-absorption and transmission coefficients of the gamma photons emitted by the uranium and thorium families as well as the potassium 40 isotope for evaluating the gamma dose rate in the considered geological samples. Transport of gamma-photons across parallelepipedic blocks of the geological materials studied has been investigated. Gamma dose rates have been evaluated in the atmosphere of different geological deposits. (author)

Monte Carlo simulation of gamma-ray total counting efficiency for a Phoswich detector

Energy Technology Data Exchange (ETDEWEB)

Yalcin, S. [Education Faculty, Kastamonu University, 37200 Kastamonu (Turkey)], E-mail: syalcin@kastamonu.edu.tr; Gurler, O. [Department of Physics, Faculty of Arts and Sciences, Uludag University, Gorukle Campus, 16059 Bursa (Turkey); Gundogdu, O. [Department of Physics, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH (United Kingdom); NCCPM, Medical Physics, Royal Surrey County Hospital, Guildford, GU2 7XX (United Kingdom); Kaynak, G. [Department of Physics, Faculty of Arts and Sciences, Uludag University, Gorukle Campus, 16059 Bursa (Turkey)

2009-01-15

The LB 1000-PW detector is mainly used for determining total alpha, beta and gamma activity of low activity natural sources such as water, soil, air filters and any other environmental sources. Detector efficiency needs to be known in order to measure the absolute activity of such samples. This paper presents results on the total gamma counting efficiency of a Phoswich detector from point and disk sources. The directions of photons emitted from the source were determined by Monte Carlo techniques and the true path lengths in the detector were determined by analytical equations depending on photon directions. Results are tabulated for various gamma energies.

Monte Carlo simulation of gamma-ray total counting efficiency for a Phoswich detector

International Nuclear Information System (INIS)

Yalcin, S.; Gurler, O.; Gundogdu, O.; Kaynak, G.

2009-01-01

The LB 1000-PW detector is mainly used for determining total alpha, beta and gamma activity of low activity natural sources such as water, soil, air filters and any other environmental sources. Detector efficiency needs to be known in order to measure the absolute activity of such samples. This paper presents results on the total gamma counting efficiency of a Phoswich detector from point and disk sources. The directions of photons emitted from the source were determined by Monte Carlo techniques and the true path lengths in the detector were determined by analytical equations depending on photon directions. Results are tabulated for various gamma energies

Measurement of the porosity of amorphous materials by gamma ray transmission methodology

International Nuclear Information System (INIS)

Pottker, Walmir Eno; Appoloni, Carlos Roberto

2000-01-01

In this work it is presented the measurement of the total porosity of TRe soil, Sandstone Berea rocks and porous ceramics samples. For the determination of the total porosity, the Arquimedes method (conventional) and the gamma ray transmission methodology were employed. The porosity measurement using the gamma methodology has a significant advantage respect to the conventional method due to the fast and non-destructive determination, and also for supplying results with a greater characterization in small scales, in relation to the heterogeneity of the porosity. The conventional methodology presents good results only for homogeneous samples. The experimental set up for the gamma ray transmission technique consisted of a 241 Am source (59,53 keV ), a NaI(Tl) scintillation detector, collimators, a XYZ micrometric table and standard gamma spectrometry electronics connected to a multichannel analyser. (author)

$\\gamma$-$\\gamma$ and $\\gamma$-p events at high energies

CERN Document Server

Schuler, Gerhard A.; Gerhard A Schuler; Torbjorn Sjostrand

1994-01-01

A real photon has a complicated nature, whereby it may remain unresolved or fluctuate into a vector meson or a perturbative q-qbar pair. Based on this picture, we previously presented a model for gamma-p events that is based on the presence of three main event classes: direct, VMD and anomalous. In gamma-gamma events, a natural generalization gives three-by-three combinations of the nature of the two incoming photons, and thus six distinct event classes. The properties of these classes are constrained by the choices already made, in the gamma-p model, of cut-off procedures and other aspects. It is therefore possible to predict the energy-dependence of the cross section for each of the six components separately. The total cross section thus obtained is in good agreement with data, and also gives support to the idea that a simple factorized ansatz with a pomeron and a reggeon term can be a good approximation. Event properties undergo a logical evolution from p-p to gamma-p to gamma-gamma events, with larger cha...

137 Cs in the soil from Pljevlja region

International Nuclear Information System (INIS)

Vukotic, P.; Jovanovic, S.; Dapcevic, S.; Zic, J.

1996-01-01

Surface layer of the seven characteristic types of soil in Pljevlja region (Montenegro) is sampled. Soil samples are taken 33 locations, at eight of them from three layers up to 20 cm in depth. Specific activity of 137 Cs is then measured in the soil samples by a method of semiconductor gamma-spectrometry. Average cesium contamination in the region is found to be about 10 times higher than the same before Chernobyl accident. 137 Cs is still in the superficial soil layer, mostly to the depth of 10 cm. Contamination level of soil has certain regularities in distribution over the region, and is the highest on the two mutually almost parallel geographic directions. 7 refs.; 1 figs.; 1 tabs

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

International Nuclear Information System (INIS)

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

1978-01-01

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

Precise measurement of {gamma}(K{yields}e {nu}({gamma}))/{gamma}(K{yields}{mu} {nu}({gamma})) and study of K{yields}e {nu} {gamma}

Energy Technology Data Exchange (ETDEWEB)

Ambrosino, F.; Massarotti, P.; Meola, S.; Napolitano, M. [Dipartimento di Scienze Fisiche dell' Universita ' ' Federico II' ' , Napoli (Italy); INFN Sezione di Napoli, Napoli (Italy); Antonelli, A.; Antonelli, M.; Bencivenni, G.; Bloise, C.; Bossi, F.; Capon, G.; Capussela, T.; Ciambrone, P.; De Lucia, E.; De Simone, P.; Dreucci, M.; Felici, G.; Gatti, C.; Giovannella, S.; Jacewicz, M.; Lanfranchi, G.; Miscetti, S.; Moulson, M.; Murtas, F.; Palutan, M.; Santangelo, P.; Sciascia, B.; Sibidanov, A.; Spadaro, T.; Venanzoni, G. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Archilli, F. [Dipartimento di Fisica dell' Universita ' ' Tor Vergata' ' , Rome (Italy); INFN Sezione di Roma Tor Vergata, Rome (Italy); Beltrame, P.; Denig, A.; Mueller, S. [Johannes Gutenberg-Universitaet, Institut fuer Kernphysik, Mainz (Germany); Bini, C.; De Santis, A.; De Zorzi, G.; Di Domenico, A.; Fiore, S.; Franzini, P.; Gauzzi, P. [Dipartimento di Fisica dell' Universita ' ' La Sapienza' ' , Rome (Italy); INFN Sezione di Roma, Rome (Italy); Bocchetta, S.; Ceradini, F.; Di Micco, B.; Nguyen, F. [Dipartimento di Fisica dell' Universita ' ' Roma Tre' ' , Rome (Italy); INFN Sezione di Roma Tre, Rome (Italy); Branchini, P.; Graziani, E.; Passeri, A.; Tortora, L. [INFN Sezione di Roma Tre, Rome (Italy); Capriotti, D. [Dipartimento di Fisica dell' Universita ' ' Roma Tre' ' , Rome (Italy); Di Donato, C. [INFN Sezione di Napoli, Napoli (Italy); Kulikov, V. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Lee-Franzini, J. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); State University of New York, Physics Department, Stony Brook (United States); Martini, M.; Patera, V.; Versaci, R. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Dipartimento di Energetica dell' Universita ' ' La Sapienza' ' , Rome (Italy); Valente, P. [INFN Sezione di Roma, Rome (Italy)

2009-12-15

We present a precise measurement of the ratio R{sub K}={gamma}(K{yields}e{nu}({gamma}))/{gamma}(K{yields}{mu}{nu}({gamma})) and a study of the radiative process K{yields}e{nu}{gamma}, performed with the KLOE detector. The results are based on data collected at the Frascati e{sup +}e{sup -} collider DA {phi}NE for an integrated luminosity of 2.2 fb{sup -1}. We find R{sub K}=(2.493{+-}0.025{sub stat}{+-}0.019{sub syst}) x 10{sup -5}, in agreement with the Standard Model expectation. This result is used to improve constraints on parameters of the Minimal Supersymmetric Standard Model with lepton flavor violation. We also measured the differential decay rate d {gamma}(K{yields}e{nu}{gamma})/dE{sub {gamma}} for photon energies 10gamma}}<250 MeV. Results are compared with predictions from theory. (orig.)

Use of neutron water and gamma density gauges in soil water studies

International Nuclear Information System (INIS)

Kirda, C.

1990-01-01

Irrigation practices should be improved to increase effective use of water and thereby increasing irrigated areas as well as securing soil productivity under irrigated agriculture. Under dry farming systems of rainfed agriculture, different tillage practices should be tested for improved soil water conservation and rain harvesting. The research work addressing the above mentioned problems requires methods to measure soil water content accurately and conveniently. In the following article, the methods which are currently used to measure field soil water content were discussed. 34 refs, 13 figs, 13 tabs

Using proximal soil sensors and fuzzy classification for mapping Amazonian Dark Earths

Directory of Open Access Journals (Sweden)

Mats Söderström

2013-12-01

Full Text Available We tested if hand-carried field proximal soil sensing (PSS can be used to map the distribution of anthropogenic Amazonian Dark Earths (ADE. ADE soils are rich in archaeological artefacts, nutrients, organic matter and carbon in the very stable form of pyrogenic carbon, also referred to as black carbon or biochar. To test the capacity of PSS to detect signature ADE properties we measured electrical conductivity (ECa, magnetic susceptibility (MSa and gamma ray data by transect sampling and compared these readings, using fuzzy classification, with datasets on chemical soil properties from a 28 ha large study area located on the Belterra Plateau of the Lower Amazon in northern Brazil. Results indicate that ECa and MSa measurements were good indicators of ADE signatures, but that the gamma radiation sensor was less useful in the deeply weathered soils. PSS and fuzzy classification can be used for rapid field mapping of ADE for both agricultural and archaeological purposes.

Investigation of elemental and radiological contamination of soils in two shipyards in Chittagong, Bangladesh

International Nuclear Information System (INIS)

Uddin, M. Shuza; Shariff, M. Asad; Hasan, M. Mehedi

2014-01-01

An analysis of metallic elements and natural radioactivity in soils collected from two shipyards and their surroundings in Chittagong, Bangladesh is presented. The elemental concentrations of the metals Cr, Mn, Fe, Ni and Cu were obtained by PIXE analysis with a 3 MV Tandem Accelerator, and the radioactivity of 226 Ra, 232 Th and 40 K was determined using HPGe gamma-ray spectrometry. From the mean specific activities of the three radionuclides in soil samples, the radium equivalent activity, the gamma absorbed dose rate, the annual effective dose rate and the external hazard index were calculated. The study was focused on investigation of soil contamination via shipbreaking activities, if any. The somewhat higher contents of Cr, Mn, Fe, Ni and Cu in soil samples of shipyards, as compared to other locations, seem to be caused by the shipbreaking activities. The specific radioactivities as well as radium equivalent activity in soils of shipyards are also higher and thus possibly an indirect result of shipbreaking activities.

Investigation of elemental and radiological contamination of soils in two shipyards in Chittagong, Bangladesh

Energy Technology Data Exchange (ETDEWEB)

Uddin, M. Shuza; Shariff, M. Asad; Hasan, M. Mehedi [Tandem Accelerator Facility, Dhaka (Bangladesh). Inst. of Nuclear Science and Technology, Atomic Energy Research Establishment; Barua, Bijoy Sonker [Tandem Accelerator Facility, Dhaka (Bangladesh). Inst. of Nuclear Science and Technology, Atomic Energy Research Establishment; Chittagong Univ. of Engineering and Technology, Chittagong (Bangladesh). Dept. of Physics; Rashid, M. Abdur [Chittagong Univ. of Engineering and Technology, Chittagong (Bangladesh). Dept. of Physics; Kamal, Masud [Radioactivity Testing and Monitoring Lab. Bangladesh Atomic Energy Commission, Chittagong (Bangladesh)

2014-10-01

An analysis of metallic elements and natural radioactivity in soils collected from two shipyards and their surroundings in Chittagong, Bangladesh is presented. The elemental concentrations of the metals Cr, Mn, Fe, Ni and Cu were obtained by PIXE analysis with a 3 MV Tandem Accelerator, and the radioactivity of {sup 226}Ra, {sup 232}Th and {sup 40}K was determined using HPGe gamma-ray spectrometry. From the mean specific activities of the three radionuclides in soil samples, the radium equivalent activity, the gamma absorbed dose rate, the annual effective dose rate and the external hazard index were calculated. The study was focused on investigation of soil contamination via shipbreaking activities, if any. The somewhat higher contents of Cr, Mn, Fe, Ni and Cu in soil samples of shipyards, as compared to other locations, seem to be caused by the shipbreaking activities. The specific radioactivities as well as radium equivalent activity in soils of shipyards are also higher and thus possibly an indirect result of shipbreaking activities.

Using gamma irradiation to improve sterile turf and forage bermudagrasses

International Nuclear Information System (INIS)

Burton, G.W.; Georgia Univ., Tifton

1976-01-01

The widely-used Tif-series of turf bermudagrasses - Tifgreen, Tifway, and Tifdwarf - are vegetatively propagated sterile triploids that cannot be improved by conventional breeding methods. Dormant stolons, washed free of soil and cut into one-or two-node sections were treated with varying dosages of EMS (ethyl methane sulfonate) and gamma irradiation ranging from 7 to 12 kR. EMS failed to produce noticeable variants but gamma irradiation from a Cobalt 60 source created 158 mutants. These mutants differed in many characters such as leaf size, hairiness, stem diameter, internode length, basic plant color, herbicide tolerance, spreading rate, and nematode resistance. Attempts to improve the winterhardiness of tetraploid sterile Coastcross-1 forage bermudagrass by exposing over 1,400,000 sprigs (vegetative stems) to 7 kR of gamma rays gave chlorophyll deficient mutants but progress in increasing winterhardiness has not been established. (author)

Nuclear equipment to determine soil and water mass attenuation coefficients

International Nuclear Information System (INIS)

Zucchi, O.L.A.D.; Nascimento Filho, V.F. do

1984-01-01

The feasibility of substituting the monochannel gamma spectrometer, traditionally used in the gamma ray attenuation technique, for a less sophisticated and less expensive system of integral counting is studied. The proposed system can be operated by a non-specialized person. Three detection systems were used in the determination of the mass attenuation coefficients for different types of soil and for water. (M.A.C.) [pt

Assessment of natural radioactivity concentrations and gamma dose levels around Shorapur, Karnataka

Energy Technology Data Exchange (ETDEWEB)

Rajesh, S.; Avinash, P.; Kerur, B. R., E-mail: kerurpbk@rediffmail.com.com [Department of Physics, Gulbarga University Kalaburagi – 585 106 India (India); Anilkumar, S. [Radiation Safety Systems Division, BARC, Mumbai - 400 085 (India)

2015-08-28

This study assesses the level of background radiation around Shorapur. The study region locates the western part of the Yadgir district of Karnataka. Shorapur and Shahapur talukas are mostly composed of clay, shale sandstone, granite rock and part of study area is black soil. Thirty sample locations were selected along the length and breadth of Shorapur and Shahapur taluka. Natural radionuclide activity concentrations in soil samples were determined using 4'X4' NaI (Tl) gamma spectroscopy. Outdoor gamma dose measurements in air at 1 m above ground level were determined using Rad Eye PRD survey meter. Estimated dose values are compared with the survey meter values and found to be good agreement between them and also with the data obtained from different other areas of Karnataka and India. The average values were found to be slightly higher in the present investigation.

Feasibility, system design, and economic evaluation of radiolytic degradation of 2,3,7,8-tetrachlorodibenzo-p-dioxin on soil

International Nuclear Information System (INIS)

Hilarides, R.J.; Gray, K.A.; Guzzetta, J.; Cortellucci, N.; Sommer, C.

1996-01-01

This research shows that gamma irradiation is both a technically and economically feasible method to degrade chlorinated dioxins on soil. Approximately 99% degradation of dioxin on a model soil was achieved using gamma radiation at a dose of 800 kGy. In addition, this research determined the initial pathway of destruction, identified several controlling parameters, and developed a mass balance on degradation. The general applicability of this model behavior was successfully tested in a native contaminated soil where nearly 75% of the dioxin was destroyed at a dose of 450 kGy. Through a theoretical and conceptual understanding of radiolysis in soil, a sound basis for engineering design was established. Gamma radiation sources are commercially available, and this research outlines a new application of an established technology. A number of irradiator designs are proposed, and preliminary economic estimates are made to demonstrate that radiolysis can be a real alternative to incineration. (author)

Radiative decay of the eta-, eta'-mesons in the nonlocal quark model. [eta(eta'). --> gamma gamma. ; eta. -->. pi. /sup +/. pi. /sup -/. gamma. ; eta. -->. pi. /sup 0/2. gamma. ; eta'. -->. rho/sup 0/. gamma. ; eta'. -->. omega gamma. ;. pi. /sup 0/. -->. gamma. e/sup +/e/sup -/; eta(eta'). -->. gamma mu. /sup +/. mu. /sup -/

Energy Technology Data Exchange (ETDEWEB)

Efimov, G V; Ivanov, M A; Nogovitsyn, E A [Joint Inst. for Nuclear Research, Dubna (USSR)

1981-07-01

P..--> gamma gamma.. (P=..pi../sup 0/, eta, eta'), eta..--> pi../sup +/..pi../sup -/..gamma.., eta..--> pi../sup 0/..gamma gamma.., eta/sup 1/..-->..V..gamma.. (V=rho/sup 0/, ..omega..), p..--> gamma..l/sup +/l/sup -/ (p=..pi../sup 0/, eta, eta') radiation decays are studied for testing the applicability of the non-local quark model for description of the experimental data. The Feynman diagrams of these decays are presented, values of the widths of the Veta..--> gamma gamma.., eta..--> pi../sup +/..pi../sup -/..gamma.., eta..--> pi../sup 0/..gamma gamma.., eta'..--> gamma gamma.., eta'..-->..rho/sup 0/..gamma.., eta'..--> omega gamma.. decays are calculated and given in the form of a table. Calculations are carried out for two values of the eta eta'-crossing angle: THETA=-11 deg and -18 deg. Values of invariant amplitudes of these decays are determined for ..pi../sup 0/..--> gamma..e/sup +/e/sup -/, eta..--> gamma mu../sup +/..mu../sup -/, eta'..--> gamma mu../sup +/..mu../sup -/ decays at THETA=-11 deg and -18 deg. The best agreement with the experimental data is noted to take place at THETA=-11 deg, the determined width of the eta..--> pi../sup 0/..gamma gamma.. decays is underestimated as compared with the experimental one.

Soil and ground cover

International Nuclear Information System (INIS)

Wiechen, A.; Heine, K.; Bundesanstalt fuer Milchforschung, Kiel

1985-01-01

The monitoring programmes set up in accordance with the directives for the surveillance of effluents from nuclear installations oblige operators of such installations to take samples of vegetation (grass) and soil twice a year at the least favourable place in the industrial plant's environment, and at a reference site, for radioactivity monitoring by gamma spectroscopy. In addition, the samples are to be examined for their Sr-90 content. Data recorded over the years show that nuclear facilities do not significantly contribute to soil and vegetation contamination with Sr-90 or Cs-137. The directives require regular interlaboratory comparisons, which are coordinated by the directing centre at Kiel. (DG) [de

Radiocaesium in uncultivated soil on some locations in Croatia

International Nuclear Information System (INIS)

Petrinec, B; Franic, Z.

2005-01-01

Institute for Medical Research and Occupational Health carries out a programme of long-term monitoring of radioactive contamination of human environment in Croatia, which involves investigation of man-made fission radionuclides in soil. Contaminated soil can significantly increase exposure doses due to the indirect contamination of edible plants entering the human food chain. This article reports the specific activity of 1 37C s in soil on two locations in Croatia monitored over the last decade. Soil samples were taken from three different layers, 0-5 cm, 5-10 cm, and 10-15 cm, in the cities of Zagreb and Zadar. A gamma-ray spectrometry system based on a low-level ORTEC Ge(Li) detector (FWHM 1.82 keV at 1.33 MeV) coupled to a computerized data acquisition system was used to determine radiocaesium levels in the samples from their gamma-ray spectra. The exponential decline was found in soil samples collected in Zadar with the estimated ecological half-life of 13.5 years, while no such behaviour was observed in the samples collected near Zagreb. Transient increases in 1 37C s specific activity concentrations in Zagreb soil, such as those in 1997 and 2000, can only be partially explained by a variety of environmental physical factors that naturally fluctuate, which calls for further investigations. As with time radiocaesium signal in undisturbed soils penetrated deeper layers, it would be appropriate to study deeper soil cores in the future. No direct correlation was found between fallout radioactivity and soil radioactivity in the first layer. However, 1 37C s activity concentrations in fallout could now be regarded as no more than background variations, having no deeper impact on the existing caesium levels in soil.(author)

Assessment of radionuclides in the drone affected soils of North Waziristan Agency and Orakzai Agency (abstract)

International Nuclear Information System (INIS)

Tabinda, A.B.; Shafi, A.

2011-01-01

When the drone affected soils of North Waziristan and Orakzai Agency were exposed to high resolution gamma ray spectrometry technique to determine the activity concentration levels the results were quite alarming. The results revealed that the mean concentration for the activity of the natural radionuclides including /sup 226/Ra, /sup 232/Th, and /sup 40/K were 42.37 +- 1.85, 47.18 +- 3.45 and 471.28 +- 23.77 Bq kg/sup -1/ respectively. On the other hand the anthropogenic activities were adding radioactive Cs 137 to soils of drone affected areas of North Waziristan and Orakzai Agency with the mean activity concentration of 5.95 +- 0.25 Bq kg/sup -1/. The maximum activity concentration of /sup 137/Cs was in North Waziristan affected soil with the value of 15.15 +- 0.39. /sup 137/Cs is an anthropogenic radionuclide produced as a fission product. However the presence of /sup 137/Cs in all the soil samples reveals the anthropogenic changes in the soils. The exact source of the introduction of /sup 137/Cs is assumed to be drone bombardment. /sup 137/Cs has radioactive half life of 30.17 years and it decays by emitting gamma and beta radiations. These gamma radiations can create havoc in our environment. (author)

Gamma irradiation for sewage treatment at US army facilities

International Nuclear Information System (INIS)

Van den Berg, A.J.; Hollis, H.D.; Musselman, H.D.; Woodbridge, D.D.

1975-01-01

The US Army Corps of Engineers has been sponsoring research for many years on the use of gamma irradiation for disinfection and sterilization of sewage plant effluents. Initial research was directed to laboratory experiments using sterile solutions to determine the effects of gamma irradiation on E. coli, M-pyogenes and M-smegmatis organisms, and on the chemical constituents of sewage such as phenols, surfactants and pesticides. The results of the initial research warranted further study using municipal sewage secondary effluent as test samples. Current research is directed towards investigating the effects of radiation on the constituents of sewage sludge and on the cyst stage of the amoebic protozoa. Consideration has been given by the Corps to the management of waste-waters by disposal on land. Legal and medical reasons dictate that the plant effluents be sterilized before being used as fertilizers and soil conditioners. Gamma radiation from isotopic sources appears to be the best source of sterilizing energy for Army waste-water disposal. The Corps of Engineers is considering the construction of an experimental gamma irradiation pilot facility to validate laboratory experimental work and to establish design criteria for operating plants. The data obtained will provide a basis for performing detailed cost effectiveness studies on gamma irradiation as a method to treat secondary plant effluent. In addition, optimization work will be conducted to determine where in the sewage treatment cycle the use of gamma irradiation will produce the best results in meeting current and anticipated standards. (author)

Indoor and soil radon measurements in the Hyblean Foreland (South-East Sicily

Directory of Open Access Journals (Sweden)

G. Alessandro

2007-06-01

Full Text Available Indoor radon behavior in two sites of SE Sicily was studied as a function of the soil radon concentration. The chosen locations were Ragusa and Modica towns, placed in the Hyblean Plateau (northern margin of the African Plate. Soil samples were analysed by gamma spectrometry to determine the amount of radionuclides. Indoor air and soil gas radon measurements were simultaneously performed in both sites using active detectors. Radon in soil was measured one meter deep. A positive correlation was obtained between indoor radon concentration and the soil gas concentration.

Gamma-ray self-attenuation corrections in environmental samples

International Nuclear Information System (INIS)

Robu, E.; Giovani, C.

2009-01-01

Gamma-spectrometry is a commonly used technique in environmental radioactivity monitoring. Frequently the bulk samples that should be measured differ with respect to composition and density from the reference sample used for efficiency calibration. Correction factors should be applied in these cases for activity measurement. Linear attenuation coefficients and self-absorption correction factors have been evaluated for soil, grass and liquid sources with different densities and geometries.(authors)

Natural radioactivity levels in soils of Fiji

International Nuclear Information System (INIS)

Garimella, S.; Kumar, A.; Prasad, U.; Jafar, M.

1998-01-01

A 10 cm (diameter) x 7.5 cm NaI(Tl) gamma-ray spectrometer with a low background shield has been used to measure the natural radioactivity levels in soils of Viti Levu, the main island of Fiji. From this, the external gamma-dose which is likely to be delivered to the local population in this region is computed and found to be 99 μGy a -1 . This is well below the world average, but it is comparable to that observed in Marshall Islands and the Micronesia

Natural radioactivity levels in soils of Fiji

International Nuclear Information System (INIS)

Garimella, S.; Kumar, A.; Prasad, U.; Jafar, M.

1998-01-01

A 10 cm (diameter) x 7.5 cm NaI(TI) gamma-ray spectrometer with a low background shield has been used to measure the natural radioactivity levels in soils of Viti Levu, the main island of Fiji. From this, the external gamma-dose which is likely to be delivered to the local population in this region is computed and found to be 99 microG a -1 . This is well below the world average, but it is comparable to that observed in Marshall Islands and the Micronesia. (author). 17 refs., 3 figs., 5 tabs

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

International Nuclear Information System (INIS)

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

2014-01-01

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

A mower detector to judge soil sorting

International Nuclear Information System (INIS)

Bramlitt, E.T.; Johnson, N.R.

1995-01-01

Thermo Nuclear Services (TNS) has developed a mower detector as an inexpensive and fast means for deciding potential value of soil sorting for cleanup. It is a shielded detector box on wheels pushed over the ground (as a person mows grass) at 30 ft/min with gamma-ray counts recorded every 0.25 sec. It mirror images detection by the TNS transportable sorter system which conveys soil at 30 ft/min and toggles a gate to send soil on separate paths based on counts. The mower detector shows if contamination is variable and suitable for sorting, and by unique calibration sources, it indicates detection sensitivity. The mower detector has been used to characterize some soil at Department of Energy sites in New Jersey and South Carolina

A mower detector to judge soil sorting

Energy Technology Data Exchange (ETDEWEB)

Bramlitt, E.T.; Johnson, N.R. [Thermo Nuclear Services, Inc., Albuquerque, NM (United States)

1995-12-31

Thermo Nuclear Services (TNS) has developed a mower detector as an inexpensive and fast means for deciding potential value of soil sorting for cleanup. It is a shielded detector box on wheels pushed over the ground (as a person mows grass) at 30 ft/min with gamma-ray counts recorded every 0.25 sec. It mirror images detection by the TNS transportable sorter system which conveys soil at 30 ft/min and toggles a gate to send soil on separate paths based on counts. The mower detector shows if contamination is variable and suitable for sorting, and by unique calibration sources, it indicates detection sensitivity. The mower detector has been used to characterize some soil at Department of Energy sites in New Jersey and South Carolina.

Shielding system for the detection of radioisotopes gamma-rays emitters

International Nuclear Information System (INIS)

Nascimento Filho, V.F. do

1983-01-01

A shielding system for detection of radioisotopes gamma-rays emitters in samples of big volumes (plants, animals, soils) is presented. The detection between the beaker Marinelli and the glass tube (inside of the scintillator crystal well) is compared. The beaker Marinelli method allows a drastic reduction in the time detection of the sample. (M.A.C.) [pt

Sterilization affects soil organic matter chemistry and bioaccumulation of spiked p,p'-DDE and anthracene by earthworms

Energy Technology Data Exchange (ETDEWEB)

Kelsey, Jason W., E-mail: kelsey@muhlenberg.ed [Program in Environmental Science and Department of Chemistry, Muhlenberg College, 2400 Chew Street, Allentown, PA 18104 (United States); Slizovskiy, Ilya B.; Peters, Richard D.; Melnick, Adam M. [Program in Environmental Science and Department of Chemistry, Muhlenberg College, 2400 Chew Street, Allentown, PA 18104 (United States)

2010-06-15

Laboratory experiments were conducted to assess the effects of soil sterilization on the bioavailability of spiked p,p'-DDE and anthracene to the earthworms Eisenia fetida and Lumbricus terrestris. Physical and chemical changes to soil organic matter (SOM) induced by sterilization were also studied. Uptake of both compounds added after soil was autoclaved or gamma irradiated increased for E. fetida. Sterilization had no effect on bioaccumulation of p,p'-DDE by L. terrestris, and anthracene uptake increased only in gamma-irradiated soils. Analyses by FT-IR and DSC indicate sterilization alters SOM chemistry and may reduce pollutant sorption. Chemical changes to SOM were tentatively linked to changes in bioaccumulation, although the effects were compound and species specific. Artifacts produced by sterilization could lead to inaccurate risk assessments of contaminated sites if assumptions derived from studies carried out in sterilized soil are used. Ultimately, knowledge of SOM chemistry could aid predictions of bioaccumulation of organic pollutants. - Soil sterilization affects soil organic matter chemistry and pollutant bioaccumulation.

Characterization of leveling problems of Patagonia gamma-ray spectrometry survey, Chubut province (Argentina)

International Nuclear Information System (INIS)

Ford, Kenneth L.; Lopez, Luis E.

1998-01-01

Measuring the radioelement concentrations of the soils along traverses perpendicular to the flight line direction was performed in order to gather useful information in support of the leveling of the airborne gamma-ray spectrometer survey of Patagonia. Two sites were selected as test areas which ground and airborne spectrometric data were systematically compared to asses the nature of the leveling problems. It is suspected that variations in soil moisture may play a significant roll in the leveling variations. (author)

An overview of the measurements of soil moisture and modeling of moisture flux in FIFE

Science.gov (United States)

Wang, J. R.

1992-01-01

Measurements of soil moisture and calculations of moisture transfer in the soil medium and at the air-soil interface were performed over a 15-km by 15-km test site during FIFE in 1987 and 1989. The measurements included intensive soil moisture sampling at the ground level and surveys at aircraft altitudes by several passive and active microwave sensors as well as a gamma radiation device.

Optimization of sampling for the determination of the mean Radium-226 concentration in surface soil

International Nuclear Information System (INIS)

Williams, L.R.; Leggett, R.W.; Espegren, M.L.; Little, C.A.

1987-08-01

This report describes a field experiment that identifies an optimal method for determination of compliance with the US Environmental Protection Agency's Ra-226 guidelines for soil. The primary goals were to establish practical levels of accuracy and precision in estimating the mean Ra-226 concentration of surface soil in a small contaminated region; to obtain empirical information on composite vs. individual soil sampling and on random vs. uniformly spaced sampling; and to examine the practicality of using gamma measurements in predicting the average surface radium concentration and in estimating the number of soil samples required to obtain a given level of accuracy and precision. Numerous soil samples were collected on each six sites known to be contaminated with uranium mill tailings. Three types of samples were collected on each site: 10-composite samples, 20-composite samples, and individual or post hole samples; 10-composite sampling is the method of choice because it yields a given level of accuracy and precision for the least cost. Gamma measurements can be used to reduce surface soil sampling on some sites. 2 refs., 5 figs., 7 tabs

Effect of gamma radiation on plant growth, nodulation, nutritional status and yield of soybean

International Nuclear Information System (INIS)

Mohamed, F.A.; Hefni, E.H.; Maghraby, G.M.

1988-01-01

Field experiment was conducted under the conditions of a sandy clay-loam soil. Soybean seeds were exposed to gamma rays (0,5,10,20,40,80 and 160 Gry) before planting. Low-medium range of gamma rays (5-40 Gry), particularly at 20 Gry, considerably stimulated plant growth, nodules formation and development as well as the total uptake of N and Mn by plants. Significant increase in seed yield was obtained as a result of gamma rays ranged from 10 to 40 Gry, but the dose of 160 Gry, reduced it. The total contents of protein and oil in seeds were highly related to the produced yield, however their concentrations did not affect by the tested range of gamma rays. Generally, seed yield of soybean seemed to be positively related to the rate of plant growth, nodulation and nutritional status. Therefore, irradiation of seeds before planting with low gamma doses could be recommended to improve the productivity of soybean

Cesium-137 and natural radionuclides in soils from southern Brazil and soils and others environmental samples from Antarctic

International Nuclear Information System (INIS)

Schuch, L.A.

1993-04-01

This work presents a study of environmental artificial and natural radioactivity levels in soil samples from the Southern Brazil and in soils and other environmental samples form Antarctica. Artificial radioactivity was determined by measuring Cs-137 which is a 30.1 year half-life man-made radionuclide produced in the past by atmospheric tests of nuclear weapons. Natural radioactivity was determined by measuring some radionuclides belonging to Th-232 and U-238 natural radioactive families, and of K-40 concentrations. Several types of soils from Southern Brazil; and soil samples, marine sediments, lichens, mosses and algae collected at King George and other nearby islands (South Shetland Archipelago, Antarctica) were analyzed. A gamma-ray spectrometer was used to measure radioactivity levels of the collected samples and its overall characteristics are analyzed in this work. (author)

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

International Nuclear Information System (INIS)

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

1996-06-01

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

Transport of radioactive ions in soil by electrokinetics

International Nuclear Information System (INIS)

Buehler, M.F.; Surma, J.E.; Virden, J.W.

1994-10-01

An electrokinetic approach is being evaluated for in situ soil remediation at the Hanford Site in Richland, Washington. This approach uses an applied electric field to induce transport of both radioactive and hazardous waste ions in soil. The work discussed in this paper involves the development of a new method to monitor the movement of the radioactive ions within the soil during the electrokinetic process. A closed cell and a gamma counter were used to provide iii situ measurements of 137 Cs and 60 Co movement in Hanford soil. Preliminary results show that for an applied potential of 200 V over approximately 200 hr, 137 Cs and 60 60 were transported a distance of 4 to 5 in. The monitoring technique demonstrated the feasibility of using electrokinetics for soil separation applications

Terrestrial gamma radiation baseline mapping using ultra low density sampling methods.

Science.gov (United States)

Kleinschmidt, R; Watson, D

2016-01-01

Baseline terrestrial gamma radiation maps are indispensable for providing basic reference information that may be used in assessing the impact of a radiation related incident, performing epidemiological studies, remediating land contaminated with radioactive materials, assessment of land use applications and resource prospectivity. For a large land mass, such as Queensland, Australia (over 1.7 million km(2)), it is prohibitively expensive and practically difficult to undertake detailed in-situ radiometric surveys of this scale. It is proposed that an existing, ultra-low density sampling program already undertaken for the purpose of a nationwide soil survey project be utilised to develop a baseline terrestrial gamma radiation map. Geoelement data derived from the National Geochemistry Survey of Australia (NGSA) was used to construct a baseline terrestrial gamma air kerma rate map, delineated by major drainage catchments, for Queensland. Three drainage catchments (sampled at the catchment outlet) spanning low, medium and high radioelement concentrations were selected for validation of the methodology using radiometric techniques including in-situ measurements and soil sampling for high resolution gamma spectrometry, and comparative non-radiometric analysis. A Queensland mean terrestrial air kerma rate, as calculated from the NGSA outlet sediment uranium, thorium and potassium concentrations, of 49 ± 69 nGy h(-1) (n = 311, 3σ 99% confidence level) is proposed as being suitable for use as a generic terrestrial air kerma rate background range. Validation results indicate that catchment outlet measurements are representative of the range of results obtained across the catchment and that the NGSA geoelement data is suitable for calculation and mapping of terrestrial air kerma rate. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Collection and preparation of samples for gamma spectrometry

International Nuclear Information System (INIS)

Pan Jingquan

1994-01-01

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

In situ gamma-ray spectrometric measurements of uranium in phosphates soil

International Nuclear Information System (INIS)

Lavi, N.; Ne'eman, E.; Brenner, S.; Haquin, G.; Nir-El, Y.

1997-01-01

Abstract Radioactivity concentration of 238 U in a phosphate ores quarry was measured in situ. Independently, soil samples collected in the site were measured in the laboratory. It was disclosed that radon emanation from the soil lowers in situ results that are derived from radon daughters. Uranium concentration was found to be 121.6±1.9 mg kg -1 (authors)

The optimal dosage of 60 co gamma irradiation for obtaining salt gland mutants of exo-recretohalophyte limonium bicolor (bunge) o. kuntze

International Nuclear Information System (INIS)

Yuan, F.; Chen, M.; Yang, J.; Wang, B.

2015-01-01

Limonium bicolor (Bunge) O. Kuntze is a typical exo-recretohalophyte with multi-cellular salt glands. It is often used to improve saline-alkali soil. Seeds of L. bicolor were treated with different doses of 60 Co gamma irradiation to determine the LD50 for 60 Co gamma irradiation; the goal was to produce a relatively high number of mutants in salt gland development and salt secretion with a relatively low level of mortality. 60 Co gamma irradiation did not greatly affect germination, but an increase in gamma dose prevented the development of true leaves and reduced the percentage of seedlings that emerged from soil. The LD50 for 60 Co gamma irradiation was 120 Gy. Two mutants (few and many) were obtained under the LD50 using the screening methods - differential interference contrast microscope and leaf discs excretion model. Compared with the wild type, few and many had mutation in salt gland development, and many showed lower salt secretion rate per single salt gland than WT. These mutants would provide insight into the molecular mechanisms of salt gland development and salt secretion and into the development of salt-tolerant crop plants. (author)

Gamma transmission gauge for assay of integral water content in soil

International Nuclear Information System (INIS)

Fishman, A.; Notea, A.; Segal, Y.

1981-01-01

A photon transmission gauge applied for integral water content measurement in a soil layer was analyzed. The gauge may be used as a control unit for automatic irrigation in a field, or as a scanner employed for establishing an irrigation policy. The characteristic functions of the gauge: response and relative resolving power were developed. The functions provide parameter study at the design stage and interpretational ability at the operational stage. The model led to a design which eliminates sensitivity to water distribution in the examined soil. It is shown that a resolving power of 2% was obtained for a 2.3 mCi 137 Cs source at 53 cm below surface, in measuring water content of 0.2 g water/cm 3 soil during 1000 s. (orig.)

Emission of radon from soil

International Nuclear Information System (INIS)

Ahlberg, P.; Lindmark, A.; Rosen, B.

1980-03-01

The report deals with the measurement of radon daughters in the soil Radon migrates readily through the limestone which is superpositioned the alum shale. The level of gamma radiation is normal. Measurements have been made by the track etch technique and with Kodak film. The contents of radon daughters are shown to be due to the measuring depth. (G.B.)

PENGGUNAAN Aspergilus niger YANG DIRADIASI GAMMA SEBAGAI BIOREMEDIAN RESIDU TRIAZOFOS DAN LOGAM BERAT PADA BAWANG MERAH (Allium cepa L.

Directory of Open Access Journals (Sweden)

Beny Maulana Satria

2015-06-01

Full Text Available The use of pesticides and fertilizers containing Pb in agriculture will leave residues in soil, water, and plants. This Pb will be accumulated in the human body and, have a negative impact gradually on human health. The use of gamma-irradiation of Aspergillus niger is expected to reduce the levels of metals and residues triazofos onions. Bioremediation technique using gamma rays against a. niger is still quite a bit or a new research so the research on this is still a little The purpose of this study was to determine the effectiveness of technology A. niger low dose gamma irradiation in reducing heavy metals and low triazofos residue on onion. Apergillus niger low dose gamma irradiated, mixed with organic materials such as Kohe, rice husk and bran. The mixture is fermented for 8 days and then applied to the soil of onion in Bradford to measure levels of Pb and triazofosnya residue. The Atomic Absorption Spectrophotometer (AAS and Gas Chromatography Mass Spectrophotometer (GCMS was used in this study. The result showed Pb that goes into the water very small and more are stuck in the ground and Pb accumulated in onion is still quite high. Triazofos residue concentrations in onions undetectable or very low in quality standards established under 0,005 ppm. The conclusion of this study, Aspergillus niger were not irradiated and irradiated can withstand heavy metals Pb in soil so it goes into the water a little, but not optimal in Pb which adsorbs into the onion and pesticide residues on onions Triazofos undetected.Keywords: Aspergillus niger, residual triazofos, gamma radiation, onion

Levels and effects of natural radionuclides in soil samples of Garhwal Himalaya

International Nuclear Information System (INIS)

Manjulata Yadav; Mukesh Rawat; Anoop Dangwal; Mukesh Prasad; Gusain, G.S.; Ramola, R.C.

2014-01-01

Distribution of natural radionuclide gives significant parameter to assess the presence of gamma radioactivity and its radiological effect in our environment. Natural radionuclides are present in the form of 226 Ra, 232 Th and 40 K in soil, rocks, water, air, and building materials. Distribution of natural radionuclides depends on the type of minerals present in the soil and rocks. For this purpose gamma spectrometer is used as tool for finding the concentration of these radionuclides. The activity concentration of naturally occurring radionuclides 226 Ra, 232 Th and 40 K in these soil samples were found to vary from of 8 ± 1 Bq/kg to 50 ± 10 Bq/kg with an average 20 Bq/kg, 7 ± 1-88 ± 16 Bq/kg with an Average 26 Bq/kg and 115 ± 18-885 ± 132 Bq/kg with an average 329 Bq/kg, respectively. In this paper, we are presenting the radiological effect due to distribution of natural radionuclide present in soil of Garhwal Himalaya. (author)

Gamma radiation fields from activity deposited on road and soil surfaces

International Nuclear Information System (INIS)

Hedemann Jensen, P.

1993-12-01

Radioactive material deposited in the environment after an accidental release would cause exposure of the population living in the affected areas. The radiation field will depend on many factors such as radionuclide composition, surface contamination density, removal of activity by weathering and migration, and protective measures like decontamination, ploughing and covering by asphalt. Methods are described for calculation of air kerma rate from deposited activity on road and soil surfaces, both from the initially deposited activity and from activity distributed in the upper layer of soil as well as from activity covered by asphalt or soil. Air kerma rates are calculated for different source geometries and the results are fitted to a power-exponential function of photon energy, depth distributions in soil and horizontal dimensions. Based on this function calculations of air kerma rate can easily be made on a personal computer or programmable pocket calculator for specific radionuclide compositions and different horizontal and vertical distributions of the deposited activity. The calculations are compared to results from other methods like the Monte Carlo method and good agreement is found between the results. (au) (7 tabs., 12 ills., 8 refs.)

Gamma exposure rate reduction and residual radium-226 concentrations resulting from decontamination activities conducted at the former uranium millsite in Shiprock, New Mexico

International Nuclear Information System (INIS)

Hans, J.M. Jr.; Hurst, T.L.

1981-01-01

Gamma radiation surveys and residual radium 226 soil samples were taken as part of the decontamination activities of the former Shiprock uranium mill site in New Mexico. In order to facilitate the decontamination activities, the mill site and its contaminated environs were divided into 6 major areas. Extensive data are presented in 2 appendices of the pre- and post-decontamination gamma ray exposure rates made on mill site, and of radium 226 concentrations in surface soil samples. A training program established on the mill site by the Navajo Engineering and Construction Authority is described

Infiltration and redistribution of water in soils

International Nuclear Information System (INIS)

Stroosnijder, L.

1976-01-01

The flow of the liquid phase through a soil can be predicted from pressure gradients. Different ways of predicting infiltration for irrigation of a basin were compared: numerical approximation; semi-analytical and analytical. A partly empirical equation was developed for description of rate of infiltration, after examination of existing equations. Under certain conditions, infiltration was influenced by under or over pressure of the trapped gas phase and by swelling of clays. Complex models for redistribution were of little value in practice, since they could not be generalized and required too many physical data about the soil. A scheme was developed that grouped techniques for estimating physical properties of soil, according to cost and expertise required. A new experimental technique based on gamma transmission is described for estimating the physical properties of the soil. (Auth.)

HI-resolution gamma spectrometry measurements of U-238, TH-232, K-40 and CS-137 concentrations in soil samples from Capao Island at CTEx

International Nuclear Information System (INIS)

Oliveira, Luciano S.R.; Oliveira, Celio J.V.; Vilela, Paulo R.T.; Vital, Helio C.

2013-01-01

Absolute soil concentrations of U-238, Th-232, K-40 and Cs-137 samples collected from Capao Island have been measured by using Hi-Resolution Gamma HPGe Spectrometry. The area of interest encompasses an embankment in a mangrove swamp in Guaratiba, Rio de Janeiro, where nuclear, chemical and biological defense laboratories of the Brazilian Army Technology Center (CTEx) are located. In order to ensure that no significant environmental impact has resulted from neutron physics experiments performed in a graphite subcritical assembly in addition to the operation of two cesium-driven irradiating facilities, routine monitoring of those isotopes have been regularly performed. A total of eight 250 ml samples of mangrove and embankment soils were extracted from four sites of known coordinates within an area of 300 x 300 m 2 and remained stored for a minimum thirty-day period to allow equilibrium to be reached. Collection and preparation of samples were made according to previously established procedures. High purity germanium detectors were used to obtain high-resolution gamma spectra and counting times were required to exceed 30 hours in order to yield sufficient statistical accuracy. Energy and efficiency calibration curves of the counting system were determined by using the GENIE 2000 software for analysis of the gamma spectrum generated by nine standard sources with a total of 11 peak energies ranging from 0.05 to 1.3 MeV. The results, corrected for background, have been expressed as absolute specific activities. All experiments have been made in the Laboratory for Identification of Radiological Agents (LIAR) at CTEx. No trace of cesium-137 has been found and the measured levels of uranium-238, in the order of 10 Bq/kg, are close to the global mean. However, some data have been found to slightly exceed the expected normal range for thorium-232 (60% of samples) and potassium-40 (20% of samples). Since there is no handling of those isotopes in the site or others that could

HI-resolution gamma spectrometry measurements of U-238, TH-232, K-40 and CS-137 concentrations in soil samples from Capao Island at CTEx

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Luciano S.R.; Oliveira, Celio J.V.; Vilela, Paulo R.T.; Vital, Helio C., E-mail: vital@ctex.eb.br [Centro Tecnologico do Exercito (DDQBN/CTEX), Rio de Janeiro, RJ (Brazil). Div. de Defesa Quimica, Biologica e Nuclear. Secao de Defesa Nuclear

2013-07-01

Absolute soil concentrations of U-238, Th-232, K-40 and Cs-137 samples collected from Capao Island have been measured by using Hi-Resolution Gamma HPGe Spectrometry. The area of interest encompasses an embankment in a mangrove swamp in Guaratiba, Rio de Janeiro, where nuclear, chemical and biological defense laboratories of the Brazilian Army Technology Center (CTEx) are located. In order to ensure that no significant environmental impact has resulted from neutron physics experiments performed in a graphite subcritical assembly in addition to the operation of two cesium-driven irradiating facilities, routine monitoring of those isotopes have been regularly performed. A total of eight 250 ml samples of mangrove and embankment soils were extracted from four sites of known coordinates within an area of 300 x 300 m{sup 2} and remained stored for a minimum thirty-day period to allow equilibrium to be reached. Collection and preparation of samples were made according to previously established procedures. High purity germanium detectors were used to obtain high-resolution gamma spectra and counting times were required to exceed 30 hours in order to yield sufficient statistical accuracy. Energy and efficiency calibration curves of the counting system were determined by using the GENIE 2000 software for analysis of the gamma spectrum generated by nine standard sources with a total of 11 peak energies ranging from 0.05 to 1.3 MeV. The results, corrected for background, have been expressed as absolute specific activities. All experiments have been made in the Laboratory for Identification of Radiological Agents (LIAR) at CTEx. No trace of cesium-137 has been found and the measured levels of uranium-238, in the order of 10 Bq/kg, are close to the global mean. However, some data have been found to slightly exceed the expected normal range for thorium-232 (60% of samples) and potassium-40 (20% of samples). Since there is no handling of those isotopes in the site or others that

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

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Maharana Mandakini

2010-01-01

Full Text Available 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 238 U, 232 Th, and 40 K 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 238 U, 232 Th, and 40 K 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.

Measurement of 222Rn and 220Rn exhalation rate from soil samples of Kumaun Hills, India

Science.gov (United States)

Semwal, Poonam; Singh, Kuldeep; Agarwal, T. K.; Joshi, Manish; Pant, Preeti; Kandari, Tushar; Ramola, R. C.

2018-03-01

The source terms, i.e., exhalation and emanation from soil and building materials are the primary contributors to the radon (222Rn)/thoron (220Rn) concentration levels in the dwellings, while the ecological constraints like ventilation rate, temperature, pressure, humidity, etc., are the influencing factors. The present study is focused on Almora District of Kumaun, located in Himalayan belt of Uttarakhand, India. For the measurement of 222Rn and 220Rn exhalation rates, 24 soil samples were collected from different locations. Gamma radiation level was measured at each of these locations. Chamber technique associated with Smart Rn Duo portable monitor was employed for the estimation of 222Rn and 220Rn exhalation rates. Radionuclides (226Ra, 232Th and 40K) concentrations were also measured in soil samples using NaI(Tl) scintillation based gamma ray spectrometry. The mass exhalation rate for 222Rn was varying between 16 and 54 mBq/kg/h, while the 220Rn surface exhalation rate was in the range of 0.65-6.43 Bq/m2/s. Measured gamma dose rate for the same region varied from 0.10 to 0.31 µSv/h. Inter-correlation of exhalation rates and intra-correlation with background gamma levels were studied.

Natural radioactivity in soils from Piracicaba, SP (Brazil)

International Nuclear Information System (INIS)

Oliveira, H. de.

1988-01-01

Using high resolution gamma spectrometry, the specific radioactivity of soils and rocks from Piracicaba, SP (Brazil) was determined. For this purpose, the Ra, Th and Ac natural series and some other nuclides such as sup(40)K and sup(137)Cs were considered. Soil samples representing the main Soil Groups were collected at 60-cm depth. Typical rock samples were also collected. After initial sample preparation, the sealed sample were allowed to rest until reaching the conditions approaching the secular equilibrium. Thereafter, counting was carried out, peak areas being the measurements basis. The mean ponderated values for soil specific activity were 24.1 and 34.8 Bq.kg sup(-1) for the sup(226)Ra and sup(232)Th, respectively. (author)

Natural and artificial radioactivity in soils of forests

International Nuclear Information System (INIS)

Alvarado, E.; Segovia, N.; Gaso P, M.I.; Pena, P.; Morton, O.; Armienta, M.A.

2001-01-01

Levels of 222 Rn, 40 K, 235 U, 226 Ra and 137 Cs were studied in soils of a forest zone located at 3000 m altitude in the central portion of Mexico. the radon concentrations in different soil horizons were determined with solid state nuclear track detectors and the concentrations of 40 K, 235 U, 226 Ra and 137 Cs in soil samples were measured with a gamma spectrometer at low level coupled to a High purity Ge detector. The results indicate differences of a magnitude order in the radon concentrations inside the studied area. The levels of 40 K, 235 U, 226 Ra and 137 Cs are discussed as function of the perturbation grade of the soil and atmospheric pollution. (Author)

Measurement of water content and density of soil using photon multiplescattering

International Nuclear Information System (INIS)

Ertek, C.; Haselberger, N.

1981-04-01

A gamma-backscatter gauge for field and laboratory applications was set up for the measurement of density and water content of soil at the same time. The method works successfully between 0-40 cm depth of the soil and is superior to the neutron gauge between 0-30 cm depth. The system is extremely simple and practical and can be installed on a tractor during ploughing. The developed method also works for absolute values of densities and moisture content and is able to distinguish the bulk density changes due to vacancies in the soil or the water content taken inside the soil grains

Gamma-ray spectra from the age of the dinosaurs

International Nuclear Information System (INIS)

Johnson, M.W.

1994-01-01

Gamma-ray spectroscopy has been tested as a technique for assisting in the excavation of paleontological sites in the Morrison Formation of western New Mexico. Excavation of these sites is difficult, owing to remoteness and to environmental concerns that militate against wholesale removal of overburden. Various researchers have used remote-sensing techniques to attempt to locate sub-surface bone near known, exposed fossils, thereby to confine excavation to areas where success in finding bone is most likely. Bones accumulate uranium from surrounding rock during fossilization; accordingly, in-situ gamma-ray spectroscopy might serve to locate bone, by detecting the 609- and 1764-keV gamma rays from uranium daughters. Because of the high uranium content of fossils in the Morrison Formation, calculations suggest the feasibility of locating bone despite the presence of several cm of rock and soil overburden. Investigations at several sites with fossils of large sauropods have revealed increased count rates for the key gamma rays near exposed bone, possibly implying the presence of additional fossils beneath the surface of the ground. However, attempts to use spectroscopy inside shafts drilled into possible fossil-bearing rock have been less successful. Results are presented and prospects for additional work discussed

Effect of the grain size of the soil on the measured activity and variation in activity in surface and subsurface soil samples

International Nuclear Information System (INIS)

Sulaiti, H.A.; Rega, P.H.; Bradley, D.; Dahan, N.A.; Mugren, K.A.; Dosari, M.A.

2014-01-01

Correlation between grain size and activity concentrations of soils and concentrations of various radionuclides in surface and subsurface soils has been measured for samples taken in the State of Qatar by gamma-spectroscopy using a high purity germanium detector. From the obtained gamma-ray spectra, the activity concentrations of the 238U (226Ra) and /sup 232/ Th (/sup 228/ Ac) natural decay series, the long-lived naturally occurring radionuclide 40 K and the fission product radionuclide 137CS have been determined. Gamma dose rate, radium equivalent, radiation hazard index and annual effective dose rates have also been estimated from these data. In order to observe the effect of grain size on the radioactivity of soil, three grain sizes were used i.e., smaller than 0.5 mm; smaller than 1 mm and greater than 0.5 mm; and smaller than 2 mm and greater than 1 mm. The weighted activity concentrations of the 238U series nuclides in 0.5-2 mm grain size of sample numbers was found to vary from 2.5:f:0.2 to 28.5+-0.5 Bq/kg, whereas, the weighted activity concentration of 4 degree K varied from 21+-4 to 188+-10 Bq/kg. The weighted activity concentrations of 238U series and 4 degree K have been found to be higher in the finest grain size. However, for the 232Th series, the activity concentrations in the 1-2 mm grain size of one sample were found to be higher than in the 0.5-1 mm grain size. In the study of surface and subsurface soil samples, the activity concentration levels of 238 U series have been found to range from 15.9+-0.3 to 24.1+-0.9 Bq/kg, in the surface soil samples (0-5 cm) and 14.5+-0.3 to 23.6+-0.5 Bq/kg in the subsurface soil samples (5-25 cm). The activity concentrations of 232Th series have been found to lie in the range 5.7+-0.2 to 13.7+-0.5 Bq/kg, in the surface soil samples (0-5 cm)and 4.1+-0.2 to 15.6+-0.3 Bq/kg in the subsurface soil samples (5-25 cm). The activity concentrations of 4 degree K were in the range 150+-8 to 290+-17 Bq/kg, in the surface

Application of the similitude principle to gamma-gamma density measurements; Application du principe de similitude a la mesure gamma-gamma de densite

Energy Technology Data Exchange (ETDEWEB)

Czubek, J A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires. Departement d' Electronique Generale, Service d' Electronique Industrielle; Institut de Recherches Nucleaires, Dep. VI, Cracow (Poland)

1966-07-01

The work presented here deals with the problem of the application of the similitude principle to rock density measurements by the gamma-gamma method. A formula is presented which makes it possible to transform results of gamma-gamma measurements carried out on models in order to make them suitable for comparison with results obtained under actual field conditions. Both the space coordinates and the densities are transformed. This transformation makes it possible to obtain a calibration curve as a function of the density for a gamma-gamma probe using only a single model of given density. The influence has also been studied of the chemical composition on the results obtained from gamma-gamma measurements. A method has been developed for estimating the equivalent Z parameter of the medium; the possibility of completely eliminating the influence of the chemical composition of the medium on the measurement results has been studied. (author) [French] L'etude presentee ci-dessous traite le probleme de l'application du principe de similitude aux mesures de densite des roches par la methode gamma-gamma. Nous indiquons une formule qui permet de transformer les resultats des mesures gamma-gamma effectuees sur les modeles pour les comparer aux resultats obtenus dans les conditions reelles sur le terrain. On transforme les coordonnees spatiales ainsi que les densites. Cette transformation donne la possibilite d'obtenir une courbe d'etalonnage (en fonction de la densite) pour une sonde gamma-gamma en utilisant un seul modele de densite donnee. On a etudie aussi l'influence de la composition chimique sur les resultats obtenus des mesures gamma-gamma. On a etabli une methode d'estimation du parametre Z equivalent du milieu, ainsi que la possibilite d'eliminer completement l'influence de la composition chimique du milieu sur les resultats des mesures de densite. (auteur)

Dynamics of bacterial communities in two unpolluted soils after spiking with phenanthrene: soil type specific and common responders

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Guo-Chun eDing

2012-08-01

Full Text Available Considering their key role for ecosystem processes, it is important to understand the response of microbial communities in unpolluted soils to pollution with polycyclic aromatic hydrocarbons (PAH. Phenanthrene, a model compound for PAH, was spiked to a Cambisol and a Luvisol soil. Total community DNA from phenanthrene-spiked and control soils collected on days 0, 21 and 63 were analyzed based on PCR-amplified 16S rRNA genefragments. Denaturing gradient gel electrophoresis (DGGE fingerprints of bacterial communities increasingly deviated with time between spiked and control soils. In taxon specific DGGE, significant responses of Alphaproteobacteria and Actinobacteria became only detectable after 63 days, while significant effects on Betaproteobacteria were detectable in both soils after 21 days. Comparison of the taxonomic distribution of bacteria in spiked and control soils on day 63 as revealed by pyrosequencing indicated soil type specific negative effects of phenanthrene on several taxa, many of them belonging to the Gamma-, Beta- or Deltaproteobacteria. Bacterial richness and evenness decreased in spiked soils. Despite the significant differences in the bacterial community structure between both soils on day 0, similar genera increased in relative abundance after PAH spiking, especially Sphingomonas and Polaromonas. However, this did not result in an increased overall similarity of the bacterial communities in both soils.

Studies of the effect of radioactive waste on the transport phenomena in soil

International Nuclear Information System (INIS)

El-Reefy, A.I.A.F

1992-01-01

This thesis introduces a new concept in the field of soil mechanics. It is an integrated work between soil and radiation in the form of gamma-rays. Chapter II was introduced to cover the basics in geotechnical engineering so as to draw a clearer picture to radiologists. Similarly, Chapter III was introduced to enable geotechnical engineers to comprehend radioactive behaviour in general. Although these two chapters are for further reading they contain various points that will be referred to regularly in the latter pages. The aim of this work is to investigate: - The effect of γ -radiations on the transport phenomena in soil. This was carried out by studying the effect of the following factors on the transmission of γ -rays with different energies: 1) Soil sample thickness 2) Grain size 3)Water content 4) Degree of compaction. - The effect of γ -radiations on moisture movement through soil. -Using the -ray transmission method to determine the soil physical properties. - Improvement of soil to increase its ability to attenuate -radiations. Experimental work took place under strict conditions at the Hot Lab. Center located at Inchas. Soil sample was sought from a nearby site which eventually will be the actual radioactive disposal site. The physical properties of the soil sample were determined as well as its grain size distribution. Accurate and detailed data on the gamma rays transport phenomena in soils was obtained using an up to date γ -radiation measurement technique. Finally, the extensive data obtained throughout this research was recorded and analyzed to ultimately approach our aim

Separate assessment of natural beta and gamma dose-rates with TL from α-Al2O3:C single-crystal chips

International Nuclear Information System (INIS)

Kalchgruber, R.; Wagner, G.A.

2006-01-01

A measurement procedure was developed for fast and separate assessment of beta and gamma dose-rates in natural sediments using highly sensitive α-Al 2 O 3 :C single-crystal chips. The dosemeters were buried for periods from two days to three weeks in sediments with different layer structure and homogeneity. For each measurement, a pair of dosemeters was buried, in order to assess beta and gamma dose-rates separately. One dosemeter was wrapped only in thin plastic foil to shield it from alpha radiation, thus measuring beta + gamma components. The second one, used for the gamma component only, was packed additionally in a 1mm copper container for absorption of beta radiation. For calibration, another set of dosemeters was buried in reference soil with a well-known dose-rate and similar content of radioactive nuclides. By comparing the thermally stimulated luminescence signals from the dosemeters the gamma dose-rate and also, by subtraction, the beta dose-rate in the unknown soil could be determined. The calculated uncertainties were 5-7% and 10%, respectively. The resulting dose-rates for homogeneous and inhomogeneous media were compared with the results obtained by Ge- and on-site NaI-gamma-ray spectrometry. An agreement within 2σ-error limits was found for homogeneous media after only few days of exposure

Natural radioactivity and dose rates for soil samples around Tiruchirapalli, South India using γ-ray spectrometry

International Nuclear Information System (INIS)

Senthilkumar, Bojarajan; Manikandan, Sabapathy; Musthafa, Mohamed Saiyad

2012-01-01

The activity concentrations and the gamma-absorbed dose rates of the naturally occurring radionuclides 226 Ra, 232 Th, and 40 K were determined for 40 soil samples collected from Tiruchirapalli, South India, using γ-ray spectrometry. The average activity concentrations of 226 Ra, 232 Th, and 40 K in the soil samples were found to be 29.9, 39.0, and 369.7 Bq kg -1 , respectively. The measured activity concentrations of both 226 Ra and 40 K in the soil were lower than the world average, whereas, the activity of 232 Th was higher than the world average. The concentrations of these radionuclides were also compared with the average activity of the Indian soil. The radiological hazard index was calculated and compared with the internationally approved values. The average external absorbed gamma dose rate was observed to be 79.9 nGy h -1 , with a corresponding average annual effective dose of 97.9 mSv y -1 , which was above the world average values. The values of Ra eq and H ex were found to be within the criterion limit, whereas, the radioactivity level index (l γ ) and total gamma dose rate were above the worldwide average values. (author)

A comparative study of 232Th and 238U activity estimation in soil samples by gamma spectrometry and neutron activation analysis technique

International Nuclear Information System (INIS)

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

2012-01-01

Neutron activation analysis (NAA) is a well-established analytical technique. It has many advantages as compared to the other commonly used techniques. NAA can be performed in a variety of ways depending on the element, its activity level in the sample, interference from the sample matrix and other elements, etc. This technique is used to get high analytical sensitivity and low detection limits (ppm to ppb). The high sensitivity is due to the irradiation at high neutron flux available from the research reactors and the activity measurement is done using high resolution HPGe detectors. In this paper, the activity estimation of soil samples using neutron activation and direct gamma spectrometry methods are compared. Even though the weights of samples considered and samples preparation methods are different for these two methods, the estimated activity values are comparable. (author)

Natural radioactivity and metal concentrations in soil samples taken along the Izmir - Ankara E-023 highway, Turkey

International Nuclear Information System (INIS)

Baba, A.; Bassari, A.; Erees, F; Cam, S.

2004-01-01

The specific activity and the gamma-absorbed dose rates of the terrestrial naturally occurring radionuclides ( 238 U, 232 Th, and 40 K) were determined in roadside soil obtained from fifteen sites along Izmir-Ankara Highway, using gamma-ray spectrometry. The soil activity ranged from 42.6 to 47.3 Bqkg -1 for 238 U, 31.8 to 36.3 Bqkg -1 for 232 Th, and 432 to 488 Bqkg -1 for 40 K. The highest mean value of 238 U was found in the soil samples obtained from a site close to the intersection of the roads. The study yielded an annual effective dose equivalent in the range of 58 - 80 μSv. The average value falls within the global range of outdoor radiation exposure given in UNSCEAR-2000 publications. Also Ca, Ti, Fe, Cu, Zn, Rb, Sr and Zr concentrations were determined in roadside soil. Rb, Sr, Zr and Zn concentrations in roadside soil around the intersection of the roads were higher than maximum concentration levels of these heavy metals in normal soil

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

International Nuclear Information System (INIS)

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

1995-04-01

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

Sensitivity to Antibiotics of Bacteria Exposed to Gamma Radiation Emitted from Hot Soils of the High Background Radiation Areas of Ramsar, Northern Iran

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Seyed Mohammad Javad Mortazavi

2017-04-01

Full Text Available Background: Over the past several years our laboratories have investigated different aspects of the challenging issue of the alterations in bacterial susceptibility to antibiotics induced by physical stresses. Objective: To explore the bacterial susceptibility to antibiotics in samples of Salmonella enterica subsp. enterica serovar Typhimurium (S. typhimurium, Staphylococcus aureus, and Klebsiella pneumoniae after exposure to gamma radiation emitted from the soil samples taken from the high background radiation areas of Ramsar, northern Iran. Methods: Standard Kirby-Bauer test, which evaluates the size of the zone of inhibition as an indicator of the susceptibility of different bacteria to antibiotics, was used in this study. Results: The maximum alteration of the diameter of inhibition zone was found for K. pneumoniae when tested for ciprofloxacin. In this case, the mean diameter of no growth zone in non-irradiated control samples of K. pneumoniae was 20.3 (SD 0.6 mm; it was 14.7 (SD 0.6 mm in irradiated samples. On the other hand, the minimum changes in the diameter of inhibition zone were found for S. typhimurium and S. aureus when these bacteria were tested for nitrofurantoin and cephalexin, respectively. Conclusion: Gamma rays were capable of making significant alterations in bacterial susceptibility to antibiotics. It can be hypothesized that high levels of natural background radiation can induce adaptive phenomena that help microorganisms better cope with lethal effects of antibiotics.

Sensitivity to Antibiotics of Bacteria Exposed to Gamma Radiation Emitted from Hot Soils of the High Background Radiation Areas of Ramsar, Northern Iran.

Science.gov (United States)

Mortazavi, Seyed Mohammad Javad; Zarei, Samira; Taheri, Mohammad; Tajbakhsh, Saeed; Mortazavi, Seyed Alireza; Ranjbar, Sahar; Momeni, Fatemeh; Masoomi, Samaneh; Ansari, Leila; Movahedi, Mohammad Mehdi; Taeb, Shahram; Zarei, Sina; Haghani, Masood

2017-04-01

Over the past several years our laboratories have investigated different aspects of the challenging issue of the alterations in bacterial susceptibility to antibiotics induced by physical stresses. To explore the bacterial susceptibility to antibiotics in samples of Salmonella enterica subsp. enterica serovar Typhimurium ( S. typhimurium ), Staphylococcus aureus , and Klebsiella pneumoniae after exposure to gamma radiation emitted from the soil samples taken from the high background radiation areas of Ramsar, northern Iran. Standard Kirby-Bauer test, which evaluates the size of the zone of inhibition as an indicator of the susceptibility of different bacteria to antibiotics, was used in this study. The maximum alteration of the diameter of inhibition zone was found for K. pneumoniae when tested for ciprofloxacin. In this case, the mean diameter of no growth zone in non-irradiated control samples of K. pneumoniae was 20.3 (SD 0.6) mm; it was 14.7 (SD 0.6) mm in irradiated samples. On the other hand, the minimum changes in the diameter of inhibition zone were found for S. typhimurium and S. aureus when these bacteria were tested for nitrofurantoin and cephalexin, respectively. Gamma rays were capable of making significant alterations in bacterial susceptibility to antibiotics. It can be hypothesized that high levels of natural background radiation can induce adaptive phenomena that help microorganisms better cope with lethal effects of antibiotics.

Radioactivity levels of 238U and 232Th, the α and β activities and associated dose rates from surface soil in Ulu Tiram, Malaysia

International Nuclear Information System (INIS)

Abdul Rahman, A.T.; Ramli, A.T.

2007-01-01

A survey was carried out to determine terrestrial gamma radiation dose rates, the concentration level of 238 U and 232 Th and α and β activities for the surface soil in Ulu Tiram, Malaysia. A 125 measurements were performed using a NaI(Tl) gamma-ray detector with crystal size of 1' x 1' on 15 soil samples collected from the site area about 102 km 2 . 238 U and 232 Th concentrations were determined in soils by using hyper pure germanium (HPGe) gamma-ray spectrometry. The activity of α and β from the surface soil was counted by using alpha beta counting system. The average value of 238 U and 232 Th concentrations in soil samples collected are 3.63±0.39 ppm within the range of 1.74±0.20 to 4.58±0.48 and 43.00±2.31 ppm within the range of 10.68±0.76 to 82.10±4.01 ppm, respectively. The average estimate of α and β activity in soil samples collected are 0.65±0.09 Bq x g -1 and 0.68±0.08 Bq x g -1 , respectively. The average of terrestrial gamma-radiation dose rates measured in Ulu Tiram was found to be 200 nGy x h -1 , within the range of 96 to 409 nGy x h -1 . The population weighted outdoor annual effective dose was 1.2 mSv. (author)

Tests of the space gamma spectrometer prototype at the JINR experimental facility with different types of neutron generators

Science.gov (United States)

Litvak, M. L.; Vostrukhin, A. A.; Golovin, D. V.; Dubasov, P. V.; Zontikov, A. O.; Kozyrev, A. S.; Krylov, A. R.; Krylov, V. A.; Mitrofanov, I. G.; Mokrousov, M. I.; Repkin, A. N.; Timoshenko, G. N.; Udovichenko, K. V.; Shvetsov, V. N.

2017-07-01

The results of the tests of the HPGe gamma spectrometer performed with a planetary soil model and different types of pulse neutron generators are presented. All measurements have been performed at the experimental nuclear planetary science facility (Joint Institute for Nuclear Research) for the physical calibration of active gamma and neutron spectrometers. The aim of the study is to model a space experiment on determining the elemental composition of Martian planetary matter by neutron-induced gamma spectroscopy. The advantages and disadvantages of a gas-filled neutron generator in comparison with a vacuum-tube neutron generator are examined.

Radionuclide content of soils from Barrio Islote, Arecibo, Puerto Rico

International Nuclear Information System (INIS)

Block, A.McB.; Clements, R.G.

1976-06-01

The purpose of this report is to present and interpret gamma ray energy spectra from natural radioactivity and fallout radionuclides measured on soil samples collected in the projected thermonuclear power plant exclusion zone in Barrio Islote, Puerto Rico

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

International Nuclear Information System (INIS)

Da Silva, Jose Ribamar Silveira

1999-01-01

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

A nonlinear wavelet method for data smoothing of low-level gamma-ray spectra

International Nuclear Information System (INIS)

Gang Xiao; Li Deng; Benai Zhang; Jianshi Zhu

2004-01-01

A nonlinear wavelet method was designed for smoothing low-level gamma-ray spectra. The spectra of a 60 Co graduated radioactive source and a mixed soil sample were smoothed respectively according to this method and a 5 point smoothing method. The FWHM of 1,332 keV peak of 60 Co source and the absolute activities of 238 U of soil sample were calculated. The results show that the nonlinear wavelet method is better than the traditional method, with less loss of spectral peak and a more complete reduction of statistical fluctuation. (author)

Spatial distribution of 40K, 228Ra, 226Ra, 238U and 137Cs in surface soil layer observed at small areas

International Nuclear Information System (INIS)

Barisic, D.; Lulic, S.; Prohic, E.; Culinovic, M.

1997-01-01

The main goal of this study is to give a more detailed insight into spatial radionuclide distribution in soils. It has been necessary in order to plant the future soil sampling procedure that would assure the representative soil samples for broader areas that are usually covered by in situ gamma-spectrometry measurements or aerial gamma-ray spectrometry. The spatial distributions of natural radionuclides and 137 Cs activity in surface soil layer were studed in five regular grids, consisting of 9 points each. The distances between sampled points were 30 cm (A grid), 2.45 m (B grid), 19.5 m (C grid), 156 m (D grid) and 213 m (E grid), respectively. Soil samples were dominantly taken at agricultural ploughed fields from areas of ca. 315 cm 2 (circle of a. 20 cm diameter), from surface up to 15 cm depth. The results indicate that representative soil sample must cover the broader area to provide data that could be compared with data collected by aerial gamma-spectrometry. The average sample on each locality must be prepared from several point samples. It seems that the central point and four points, each at approximately 50-100 m N, S, E, and W from the central point, could be enough

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

International Nuclear Information System (INIS)

Carrier, F.

2005-01-01

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

Radiation exposure parameters resulting from the radionuclides in soil collected from Manavalakurichi

International Nuclear Information System (INIS)

Jose, Reeba Maria; Ben Byju, S.; Arunima, S.; Jojo, P.J.

2014-01-01

Naturally occurring radioactive materials (NORMS) are and have always been a part of our environment. Exposure to ionizing radiation film natural sources is a continuous and unavoidable feature of life on earth. Human beings are exposed outdoors to the natural terrestrial radiation that originates predominantly from the upper 30 cm of the soil. Only radionuclides with half-lives comparable with the age of the earth or their corresponding decay products existing in terrestrial material such as 232 Th, 238 U and 40 K are of great interest. The radiological implication of these radionuclides is due to the gamma ray exposure of the body and irradiation of lung tissue from inhalation of radon and its daughters. Therefore the assessment of gamma radiation dose from natural source is of particular importance as natural radiation is the largest contributor to the external dose of the world population. The natural environmental radioactivity and the external exposure due to gamma radiation depend primarily on the geology and geographical condition and appear at different levels in the soils of each region in the world. A systematic radiological survey has been carried out in the region of high level natural radioactive area in South West India to assess the natural gamma radiation level

Development of a soil water dispersion index (SOWADIN) for testing the effectiveness of a soil-wetting agent

International Nuclear Information System (INIS)

Sawada, Y.; Aylmore, L.A.G.; Hainsworth, J.M.

1989-01-01

Computer-assisted tomography (CAT) applied to gamma-ray attenuation measurement has been used to develop an index termed the soil water dispersion index (SOWADIN), which describes quantitatively the amount and distribution of water in soil columns. The index, which is determined by classifying pixels in a scanned slice into three categories according to their attenuation coefficients, contains two numerical values. The first value corresponds to the water content of the scanned slice and the second value is a measure of the dispersion of the water throughout the slice. Artificially wetted zones were created in soil columns to give one-third of the scanned layer wetted with various patterns of wetted-area distribution. The SOWADIN values obtained accurately reflected the differences in water distribution associated with the different patterns. Application of SOWADIN to columns of a water-repellent sand before and after treatment with a soil-wetting agent clearly illustrates both the increase in water content and improvement in water distribution in the soil column following treatment. 33 refs., 3 figs., 2 tabs

Physiological response of soybean and wheat to gamma radiation and gibberellin

International Nuclear Information System (INIS)

Maghraby, G. M.

1997-01-01

The main objective of this work is to study and evaluate physiological effects of gamma radiation and/or GA 3 on plant growth, nutritional status of plants, yield and some quality of seeds of soybean and wheat. Two field experiments were conducted under the condition of clay loam soil at kaliobia governorate during 1993 and 1994 and 1992/1993 and 1993/1994 for soybean and wheat, respectively. Growth of soybean and wheat plants was considerably stimulated by irradiation seeds before sowing with low gamma doses and/or concentration of Ga 3. Maximum growth of both plants was obtained by the combined treatment of 2 0 Gy x 25 ppm GA 3 and 1 0 Gy x 100 ppm GA 3 for soybean and wheat, respectively. On the contrary high gamma doses and/or high rates of GA 3 depressed growth of both plants. Low gamma doses and/or GA 3 at low concentration greatly encouraged nutrients uptake by soybean and wheat plants, i.e., N, Fe, Mn and Zn which seemed to be positively related to plant growth. Whereas, high doses and/or high concentrations of GA 3 reduced these nutrients in plant. 53 tabs., 5 figs., 91 refs

Natural radionuclides in soil profiles surrounding the largest coal-fired power plant in Serbia

OpenAIRE

Tanić Milan N.; Janković-Mandić Ljiljana J.; Gajić Boško A.; Daković Marko Z.; Dragović Snežana D.; Bačić Goran G.

2016-01-01

This study evaluates the influence of the largest Serbian coal-fired power plant on radionuclide concentrations in soil profiles up to 50 cm in depth. Thirty soil profiles were sampled from the plant surroundings (up to 10 km distance) and analyzed using standard methods for soil physicochemical properties and gamma ray spectrometry for specific activities of natural radionuclides (40K, 226Ra and 232Th). Spatial and vertical distribution of radionuclides wa...

Fingerprinting: Modelling and mapping physical top soil properties with the Mole

Science.gov (United States)

Loonstra, Eddie; van Egmond, Fenny

2010-05-01

The Mole is a passive gamma ray soil sensor system. It is designed for the mobile collection of radioactive energy stemming from soil. As the system is passive, it only measures energy that reaches the surface of soil. In general, this energy comes from upto 30 to 40 cm deep, which can be considered topsoil. The gathered energy spectra are logged every second, are processed with the method of Full Spectrum Analysis. This method uses all available spectral data and processes it with a Chi square optimalisation using a set of standard spectra into individual nuclide point data. A standard spectrum is the measured full spectrum of a specific detector derived when exposed to 1 Bq/kg of a nuclide. With this method the outcome of the surveys become quantitative.The outcome of a field survey with the Mole results in a data file containing point information of position, Total Counts and the decay products of 232Th, 238U, 40K and 137Cs. Five elements are therefor available for the modelling of soil properties. There are several ways for the modelling of soil properties with sensor derived gamma ray data. The Mole generates ratio scale output. For modelling a quantitative deterministic approach is used based on sample locations. This process is called fingerprinting. Fingerprinting is a comparison of the concentration of the radioactive trace elements and the lab results (pH, clay content, etc.) by regression analysis. This results in a mathematical formula describing the relationship between a dependent and independent property. The results of the sensor readings are interpolated into a nuclide map with GIS software. With the derived formula a soil property map is composed. The principle of fingerprinting can be applied on large geographical areas for physical soil properties such as clay, loam or sand (50 micron), grain size and organic matter. Collected sample data of previous field surveys within the same region can be used for the prediction of soil properties elsewhere

Natural radionuclides in soils from Sao Paulo State cerrado forest

International Nuclear Information System (INIS)

Miranda, Marcia V.F.E.S.; Farias, Emerson E.G. de; Cantinha, Rebeca S.; Franca, Elvis J. de

2015-01-01

Considering the long life history, forests should be preferentially evaluated for the monitoring of radionuclides, mainly artificial radioisotopes. However, little is known about nuclides from Uranium and Thorium series, as well as, K-40, in soils from the Sao Paulo State forests. Soils are the main reservoir of natural radionuclides for vegetation, thereby deserving attention. Taking into account the advantages of High-Resolution Gamma-ray Spectrometry (HRGS), diverse radionuclides can be quantified simultaneously. In this work natural radionuclides in soils from the Estacao Ecologica de Assis were evaluated by HRGS. Samples of 0-10 cm depth were collected under crown projection of most abundant tree species of long-term plots installed within the Estacao Ecologica de Assis, Sao Paulo State, Brazil. After drying and milling until 0.5 mm particle size, test portions of 30 g were transferred to polypropylene vials, sealed with silicone and kept under controlled conditions until 30 days to achieve secular equilibrium. A group of gamma-ray spectrometers was used to analyze about 27 samples by 80,000 seconds. Activity concentrations of Pb-214, Ac-228 and K-40 and their respective expanded analytical uncertainties at the 95% confidence level were calculated by Genie software from Canberra. Abnormal values were not detected for radionuclides in soils samples, however K-40 activity concentrations changed considerably due to the mineral cycling, in which K and, consequently K-40, is mainly stocked in vegetation in spite of soils. (author)

Natural radionuclides in soils from Sao Paulo State cerrado forest

Energy Technology Data Exchange (ETDEWEB)

Miranda, Marcia V.F.E.S.; Farias, Emerson E.G. de; Cantinha, Rebeca S.; Franca, Elvis J. de, E-mail: mvaleria@cnen.gov.br, E-mail: emersonemiliano@yahoo.com.br, E-mail: rebecanuclear@gmail.com, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

2015-07-01

Considering the long life history, forests should be preferentially evaluated for the monitoring of radionuclides, mainly artificial radioisotopes. However, little is known about nuclides from Uranium and Thorium series, as well as, K-40, in soils from the Sao Paulo State forests. Soils are the main reservoir of natural radionuclides for vegetation, thereby deserving attention. Taking into account the advantages of High-Resolution Gamma-ray Spectrometry (HRGS), diverse radionuclides can be quantified simultaneously. In this work natural radionuclides in soils from the Estacao Ecologica de Assis were evaluated by HRGS. Samples of 0-10 cm depth were collected under crown projection of most abundant tree species of long-term plots installed within the Estacao Ecologica de Assis, Sao Paulo State, Brazil. After drying and milling until 0.5 mm particle size, test portions of 30 g were transferred to polypropylene vials, sealed with silicone and kept under controlled conditions until 30 days to achieve secular equilibrium. A group of gamma-ray spectrometers was used to analyze about 27 samples by 80,000 seconds. Activity concentrations of Pb-214, Ac-228 and K-40 and their respective expanded analytical uncertainties at the 95% confidence level were calculated by Genie software from Canberra. Abnormal values were not detected for radionuclides in soils samples, however K-40 activity concentrations changed considerably due to the mineral cycling, in which K and, consequently K-40, is mainly stocked in vegetation in spite of soils. (author)

Radiological risk assessment of use of phosphate fertilizers in soil

International Nuclear Information System (INIS)

Kant, K.; Upadhyay, S. B.; Sonkawade, R. G.; Chakarvarti, S. K.

2006-01-01

The radiological impact of the use of phosphate fertilizers in soil is due to the internal irradiation of the lung by the alpha particles, short lived radon-thoron progeny and the external irradiation of the body by gamma rays emitted from radionuclides in situ. This paper describes the results of gamma spectrometric measurements of the concentration of the natural radionuclides namely 226 Ra, 232 Th and 40 K in the soil samples collected from the fields where a variety of phosphate fertilizers are being used by the farmers to enhance the crop yield. Materials and Methods: The experimental work utilizes actual measurements of 226 Ra, 232 Th and 40 K using gamma spectrometry and radon concentration and exhalation rates measurements using solid state nuclear track (LR-115, Type-ll plastic) detectors to asses a first order exposure risk for the persons working in the fields where lot of fertilizers are being used to enhance crop yield in terms of occupational exposure. Results:The concentration of Radium, Thorium and Potassium in the mixed soil sample from crop fields is 16.2 ±0.22, 68.1±1.44 and 875.0±9.68 Bq/kg, where as in barren soil sample is 9.1±0.13, 59.4±1.45 and 668.4± 8.01 Bq/kg respectively. The radium equivalent activity (Ra eq ) in the mixed soil sample from crop fields is 225.9 Bq/kg, where as in barren soil sample is 193.1 Bq/kg. The values of absorbed dose and annual effective dose (indoors and outdoors) are found to vary from 90.87 nGyh -1 to 119.71 nGyh -1 , 0.45 mSv/y to 0.59 mSv/y and 0.11 mSv/y to 0.15 mSv/y respectively in soil sample from crop fields, whereas the value of absorbed dose and annual effective dose (indoors and outdoors) is 92.29 nGyh -1 , 0.45 mSv/y, 0.11 respectively in soil sample collected from barren land. The radon concentration and exhalation rates have also been reported. Conclusion:The activity concentration, exhalation rate and absorbed dose were found to increase substantially with the use of phosphate fertilizers

AMELIORATIVE EFFECT OF GAMMA RADIATION ON SODIUM CHLORIDE STRESSED TOMATO PLANT GROWTH IN SOIL INFESTED WITH FUSARIUM OXYSPORUM F.SP. LYCOPERSICI

International Nuclear Information System (INIS)

RIZK, M.A.; BOTROS, H.W.

2009-01-01

The present study was carried out to investigate the influence of saline stress and/or gamma radiation on the tomato seedlings development, mycelial growth and sporulation of Fusarium oxysporum. Irradiation of the fungus ameliorated the detrimental effect of salinity and improved the percentage of seedlings emergence and increased the root and shoot lengths and dry weight of tomato seedlings. Also, coupling salinity with irradiation significantly increased the mycelial growth in soil and biomass gain of Fusarium oxysporum up to 2 kGy, above which the growth and sporulation were hardly affected and completely suppressed at 5 kGy. On the other hand, exposure of the tomato seeds up to 4 Gy counteracted the suppressive effect of salinity and increased the growth parameters in presence or absence of the fungus. Fusarium oxysporum f.sp. lycopersici appeared to be tolerant to salinity up to 4.8 EC (millimohse) and highly sensitive to irradiation dose 5 kGy.

Trace element analysis of soil type collected from the Manjung and central Perak

Energy Technology Data Exchange (ETDEWEB)

Azman, Muhammad Azfar, E-mail: m-azfar@nuclearmalaysia.gov.my; Hamzah, Suhaimi; Rahman, Shamsiah Abdul; Elias, Md Suhaimi; Abdullah, Nazaratul Ashifa; Hashim, Azian; Shukor, Shakirah Abd; Kamaruddin, Ahmad Hasnulhadi Che [Blok 18, Makmal Analisis Kimia (Aca/Bas), Agensi Nuklear Malaysia, 43000 Kajang, Selangor (Malaysia)

2015-04-29

Trace elements in soils primarily originated from their parent materials. Parents’ material is the underlying geological material that has been undergone different types of chemical weathering and leaching processes. Soil trace elements concentrations may be increases as a result of continuous input from various human activities, including power generation, agriculture, mining and manufacturing. This paper describes the Neutron Activation Analysis (NAA) method used for the determination of trace elements concentrations in part per million (ppm) present in the terrestrial environment soil in Perak. The data may indicate any contamination of trace elements contributed from human activities in the area. The enrichment factors were used to check if there any contamination due to the human activities (power plants, agricultural, mining, etc.) otherwise the values would serve as a baseline data for future study. The samples were collected from 27 locations of different soil series in the area at two different depths: the top soil (0-15cm) and the sub soil (15-30cm). The collected soil samples were air dried at 60°C and passed through 2 µm sieve. Instrumental Neutron Activation Analysis (NAA) has been used for the determination of trace elements. Samples were activated in the Nuclear Malaysia TRIGA Mark II reactor followed by gamma spectrometric analysis. By activating the stable elements in the samples, the elements can be determined from the intensities of gamma energies emitted by the respected radionuclides.

beta- and gamma-Comparative dose estimates on Eniwetok Atoll

Energy Technology Data Exchange (ETDEWEB)

Crase, K.W.; Gudiksen, P.H.; Robison, W.L.

1982-05-01

Eniwetok Atoll is one of the Pacific atolls used for atmospheric testing of U.S. nuclear weapons. Beta dose and gamma-ray exposure measurements were made on two islands of the Eniwetok Atoll during July-August 1976 to determine the beta and low energy gamma-contribution to the total external radiation doses to the returning Marshallese. Measurements were made at numerous locations with thermoluminescent dosimeters (TLD), pressurized ionization chambers, portable NaI detectors, and thin-window pancake GM probes. Results of the TLD measurements with and without a beta-attenuator indicate that approx. 29% of the total dose rate at 1 m in air is due to beta- or low energy gamma-contribution. The contribution at any particular site, however, is somewhat dependent on ground cover, since a minimal amount of vegetation will reduce it significantly from that over bare soil, but thick stands of vegetation have little effect on any further reductions. Integral 30-yr external shallow dose estimates for future inhabitants were made and compared with external dose estimates of a previous large scale radiological survey (En73). Integral 30-yr shallow external dose estimates are 25-50% higher than whole body estimates. Due to the low penetrating ability of the beta's or low energy gamma's, however, several remedial actions can be taken to reduce the shallow dose contribution to the total external dose.

Radionuclide analysis in the soil of Kumaun Himalaya, India, using gamma ray spectrometry

International Nuclear Information System (INIS)

Ramola, R.C.; Prasad, Ganesh; Gusain, G.S.; Choubey, V.M.; Tosheva, Z.; Kies, A.

2011-01-01

Environmental release of low levels of radioactivity can occur as a consequence of normal radionuclides present in the earth's crust. We present here the results of a survey undertaken in 2003 on the radionuclide concentration in different rock formations in the eastern part of Kumaun Himalaya. The activity concentration and gamma-absorbed dose rates of the terrestrial radionuclides caused by 226 Ra, 232 Th and 40 K were determined in the soil samples collected from the eastern part of Kumaun Himalaya. The mean concentration of 238 U and 232 Th in the earth's crust varied from 0.5 to 5 ppm (6 to 60 Bq/kg) and 2 to 20 ppm (8 to 80 Bq/kg) respectively. The reported activity concentration for the different rock formations varied from 32.6 to 1305.5 Bq/kg for 238 U, 16.3 to 136.3 Bq/kg for 232 Th and 124.6 to 1758.0 Bq/kg for 40 K. The distribution of the radionuclides varied with rock type due to different chemical properties of the measured radionuclides and the rocks. The result shows that high activity levels were found in Saryu Formation consisting of augen-gneiss, granite interbedded with schists and flaggy quartzite. The total air-absorbed dose rate in air above 1 m height was calculated from the three radionuclides ( 226 Ra, 232 Th and 40 K), which varied from 39.1 to 226.8 nGy h -1 . The internal and external health-hazard indices were calculated based on the concentration of 226 Ra, 232 Th and 40 K. Strong positive correlations were observed between 235 U and 226 Ra, 232 Th and 226 Ra, 40 K and 232 Th as well as 40 K and 226 Ra. However, no significant correlation was observed between 238 U and 226 Ra because of radioactive disequilibrium between them. (author)

Natural radioactivity in soils of the state of Rio de Janeiro (Brazil): Radiological characterization and relationships to geological formation, soil types and soil properties.

Science.gov (United States)

Ribeiro, F C A; Silva, J I R; Lima, E S A; do Amaral Sobrinho, N M B; Perez, D V; Lauria, D C

2018-02-01

Located in the south-western part of Brazil, the state of Rio de Janeiro is geotectonically contained within a complex structural province that resulted in the amalgamation of the Western Gondwana Paleocontinent. To undertake an extensive radiological characterization of this complex geological province and investigate the influence of bedrock, soil type and soil chemical-physical characteristics on natural radionuclide levels in soils, 259 surface soil samples were collected that encompassed the main soil types and geological formations throughout the state. Gamma spectrometry analysis of the samples resulted in median values of 114 Bq.kg -1 for 40 K, 32 Bq.kg -1 for 226 Ra and 74 Bq.kg -1 for 228 Ra. The median value for 226 Ra was similar to the world median value for soils, the 40 K value was well below the worldwide value, and that for 228 Ra exceeded the world median value. The intense weathering caused by the high rainfall rates and high temperatures may be responsible for the low levels of 40 K in the soils, of which the strongly acidic and clayey soils are markedly K-depleted. A soil from a high-grade metamorphic rock (granulite) presented the lowest 226 Ra (18 Bq.kg -1 ) content, whereas the highest levels for 226 Ra (92 Bq.kg -1 ) and 228 Ra (139 Bq.kg - 1) were observed in a young soil enriched in primary minerals (Leptsol). A lowland soil (Gleysol) showed the highest median of 40 K (301 Bq.kg -1 ). Strongly acidic soils tended to present high amounts of 226 Ra, and sandy soils tended to contain low levels of 228 Ra. The external radiation dose indicates that the state has a background radiation level within the natural range. Copyright © 2017 Elsevier Ltd. All rights reserved.

Surface and subsurface gamma survey of the Kellex Site, Jersey City, New Jersey: dates of survey, September 8-November 11, 1980

International Nuclear Information System (INIS)

Fritzsche, A.E.

1981-04-01

The Kellex Site of about 6.2 hectares in Jersey City, New Jersey was surveyed by an in situ gamma measuring system. The system consisted of a high purity germanium detector and electronics mounted on a tracked vehicle. The entire site was surveyed on a 20 meter grid that may be transformed to New Jersey grid coodinates. A fraction of the site was surveyed on a 5 m grid. The subsurface soil was surveyed to a 1 m depth by means of a trenching operation that brought the subsurface soil to the surface. The in situ gamma data were converted to activity concentrations of uranium, thorium and potassium in the Kellex soil. Individual measurements were compared to the mean site concentrations to ascertain those areas that differ significantly from the mean. Only 238 U and 235 U appear to exist at Kellex in significant excess of the Kellex means, which in turn approximate New Jersey natural concentrations. No Kellex soil appears to exceed the investigative guideline for 238 U of 40 pCi/g in a 400 m 2 area 20 cm thick

Use of gamma ray spectroscopy measurements for assessment of the average effective dose from the analysis of 226Ra, 232Th and 40K in soil samples

International Nuclear Information System (INIS)

Mehra, Rohit; Singh, Surinder

2008-01-01

The activity concentrations of soil samples collected from different locations of Ludhiana and Patiala districts of Punjab were determined by using HPGe detector based on high-resolution gamma spectrometry system. The range of activity concentrations of 226 Ra, 232 Th and 40 K in the soil from the studied areas varies from 23.32 Bq kg -1 to 43.64 Bq kg -1 , 104.23 Bq kg -1 to 148.21 Bq kg -1 and 289.83 Bq kg -1 to 394.41 Bq kg -1 with overall mean values of 32 Bq kg -1 , 126 Bq kg -1 and 348 Bq kg -1 respectively. The absorbed dose rate calculated from activity concentration of 226 Ra, 232 Th and 40 K ranges between 10.75 and 20.12, 64.93 and 92.33, and 11.99 and 16.32 n Gy h -1 , respectively. The total absorbed dose in the study area ranges from 91.35 n Gy h -1 to 119.76 n Gy h -1 with an average value of 107.97 n Gy h -1 . The calculated values of external hazard index (H ex ) for the soil samples of the study area range from 0.55 to 0.72. Since these values are lower than unity, therefore, according to the Radiation Protection 112 (European Commission, 1999) report, soil from these regions is safe and can be used as a construction material without posing any significant radiological threat to population. The concentration of 232 Th in soil samples of Malwa region of Punjab are higher than the world figures reported in UNSCEAR (2000). However, the concentrations for 226 Ra is very much comparable and concentration of 40 K are lower than world figures. The results obtained have shown that the indoor and outdoor effective dose due to natural radioactivity of soil samples is lower than the average national and world recommended value of 1.0 mSv.Y -1 . These values reported for radium content in soils of study area are generally low as compared to the values reported for radium concentration in soils of Himachal Pradesh. (author)

Assessment of the geometric coincidence of neutron and gamma probe measurements with solo 40 and CPN 501 B

International Nuclear Information System (INIS)

Valles, V.; Guiresse, M.; Tcherbakov, R.

1989-01-01

The distance between the gamma and neutron probe measurement centres was determined for the Nardeux Solo 40 and CPN 501 B probes. The centre of the spheres of influence was localized using a water-air interface constituted by a metal cylinder filled with 200 liters of water. For Solo 40, the discrepancy between the two measurement centres was 6 cm. This shift value, which is quite acceptable, does not require any correction for these measurements, even when the soil is heterogeneous. For CNP 501 B, the discrepancy between the neutron and gamma measurement was 11 cm, i.e. nearly twice the value observed with Solo 40. In soils with a marked vertical heterogeneity, it therefore seems preferable to operate a 11 cm shift of the probe between the moisture and density measurements [fr

Study of the $e^+ e^- \\to Z\\gamma\\gamma \\to q\\overline{q}\\gamma\\gamma$ Process at LEP

CERN Document Server

Acciarri, M.; Adriani, O.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Ambrosi, G.; Anderhub, H.; Andreev, Valery P.; Angelescu, T.; Anselmo, F.; Arefev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, L.; Balandras, A.; Baldew, S.V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillere, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B.L.; Bhattacharya, S.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J.J.; Blyth, S.C.; Bobbink, G.J.; Bohm, A.; Boldizsar, L.; Borgia, B.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J.G.; Brochu, F.; Buffini, A.; Buijs, A.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.M.; Casaus, J.; Castellini, G.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Cesaroni, F.; Chamizo, M.; Chang, Y.H.; Chaturvedi, U.K.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G.M.; Chen, H.F.; Chen, H.S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Civinini, C.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; Cotorobai, F.; de la Cruz, B.; Csilling, A.; Cucciarelli, S.; Dai, T.S.; van Dalen, J.A.; D'Alessandro, R.; de Asmundis, R.; Deglon, P.; Degre, A.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; van Dierendonck, D.; Dionisi, C.; Dittmar, M.; Dominguez, A.; Doria, A.; Dova, M.T.; Duchesneau, D.; Dufournaud, D.; Duinker, P.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Erne, F.C.; Ewers, A.; Extermann, P.; Fabre, M.; Falagan, M.A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J.H.; Filthaut, F.; Fisher, P.H.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gau, S.S.; Gentile, S.; Gheordanescu, N.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; van Gulik, R.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hasan, A.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hidas, P.; Hirschfelder, J.; Hofer, H.; Holzner, G.; Hoorani, H.; Hou, S.R.; Hu, Y.; Iashvili, I.; Jin, B.N.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Khan, R.A.; Kafer, D.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, D.; Kim, J.K.; Kirkby, Jasper; Kiss, D.; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopal, M.; Kopp, A.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Krenz, W.; Kruger, A.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Lee, H.J.; Le Goff, J.M.; Leiste, R.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Lubelsmeyer, K.; Luci, C.; Luckey, David; Lugnier, L.; Luminari, L.; Lustermann, W.; Ma, W.G.; Maity, M.; Malgeri, L.; Malinin, A.; Mana, C.; Mangeol, D.; Mans, J.; Marian, G.; Martin, J.P.; Marzano, F.; Mazumdar, K.; McNeil, R.R.; Mele, S.; Merola, L.; Meschini, M.; Metzger, W.J.; von der Mey, M.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G.B.; Moulik, T.; Muanza, G.S.; Muijs, A.J.M.; Musicar, B.; Musy, M.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Niessen, T.; Nisati, A.; Kluge, Hannelies; Ofierzynski, R.; Organtini, G.; Oulianov, A.; Palomares, C.; Pandoulas, D.; Paoletti, S.; Paolucci, P.; Paramatti, R.; Park, H.K.; Park, I.H.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pieri, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Postema, H.; Pothier, J.; Prokofev, D.O.; Prokofiev, D.; Quartieri, J.; Rahal-Callot, G.; Rahaman, M.A.; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Ranieri, R.; Raspereza, A.; Raven, G.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, Keith; Rodin, J.; Roe, B.P.; Romero, L.; Rosca, A.; Rosier-Lees, S.; Roth, Stefan; Rosenbleck, C.; Roux, B.; Rubio, J.A.; Ruggiero, G.; Rykaczewski, H.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Sanders, M.P.; Schafer, C.; Schegelsky, V.; Schmidt-Kaerst, S.; Schmitz, D.; Schopper, H.; Schotanus, D.J.; Schwering, G.; Sciacca, C.; Seganti, A.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Siedenburg, T.; Son, D.; Smith, B.; Spillantini, P.; Steuer, M.; Stickland, D.P.; Stone, A.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Sushkov, S.; Suter, H.; Swain, J.D.; Szillasi, Z.; Sztaricskai, T.; Tang, X.W.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Uchida, Y.; Ulbricht, J.; Valente, E.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobev, I.; Vorobov, A.A.; Vorvolakos, A.; Wadhwa, M.; Wallraff, W.; Wang, M.; Wang, X.L.; Wang, Z.M.; Weber, A.; Weber, M.; Wienemann, P.; Wilkens, H.; Wu, S.X.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Ye, J.B.; Yeh, S.C.; Zalite, A.; Zalite, Yu.; Zhang, Z.P.; Zhu, G.Y.; Zhu, R.Y.; Zichichi, A.; Zilizi, G.; Zimmermann, B.; Zoller, M.

2001-01-01

The process e^+e^- -> Z gamma gamma -> q q~ gamma gamma$ is studied in 0.5\\,fb-1$ of data collected with the L3 detector at centre-of-mass energies between 130.1 GeV and 201.7 GeV. Cross sections are measured and found to be consistent with the Standard Model expectations. The study of the least energetic photon constrains the quartic gauge boson couplings to -0.008 GeV-2 < a_0/\\Lambda^2 < 0.005 GeV-2 and -0.007 GeV-2 < a_c/\\Lambda^2 < 0.011 GeV-2, at 95% confidence level.

Semi-Broad-Beam Gamma Spectrometry of Some Mixtures and Solutions

International Nuclear Information System (INIS)

El-Kateb, A.H.

2000-01-01

The 33- and 662-keV X rays and gamma rays from 137 Cs and the 1173- and 1333-keV gamma rays from 60 Co have been employed as single and dual beams to study the attenuation of applied materials. These materials are soil containing water, dextrose solutions, and solutions of lithium chloride, sodium chloride, and potassium chloride. In soil the measurements covered water content ranging from saturation to nearly dry points. For dextrose, the content ranged from 0.25 g.cm -3 to zero. For the chloride solutions, the salt mass fraction was varied up to the ratio 0.1667. The setup geometry was arranged with a source-detector angle of 8.63 deg to allow good reception of the 33-keV line. The results were analyzed on the basis of the dependence of the absorption of intensity (intensities) on the content of the added component. The curves are fitted with concentration-dependent expansions, the coefficients of which are tabulated. It is concluded that soft X rays (33 keV) produce the most sensitive responses to concentrations. Correspondingly, a dual energy of 33 and 1250 keV (or 1333 keV) is the preferred combination to detect a desired component in a sample

System for gamma-gamma formation density logging while drilling

International Nuclear Information System (INIS)

Paske, W.C.

1991-01-01

The patent relates to a system for logging subterranean formations for the determination of formation density by using gamma radiation. Gamma ray source and detection means are disposed within a housing adapted for positioning within a borehole for the emission and detection of gamma rays propagating through earth formations and borehole drilling fluid. The gamma ray detection means comprises first and second gamma radiation sensors geometrically disposed within the housing, the same longitudinal distance from the gamma ray source and diametrically opposed in a common plane. A formation matrix density output signal is produced in proportion to the output signal from each of the gamma ray sensors and in conjunction with certain constants established by the geometrical configuration of the sensors relative to the gamma ray source and the borehole diameter. Formation density is determined without regard to the radial position of the logging probe within the borehole in a measuring while drilling mode. 6 figs

Very high-energy gamma rays from gamma-ray bursts.

Science.gov (United States)

Chadwick, Paula M

2007-05-15

Very high-energy (VHE) gamma-ray astronomy has undergone a transformation in the last few years, with telescopes of unprecedented sensitivity having greatly expanded the source catalogue. Such progress makes the detection of a gamma-ray burst at the highest energies much more likely than previously. This paper describes the facilities currently operating and their chances for detecting gamma-ray bursts, and reviews predictions for VHE gamma-ray emission from gamma-ray bursts. Results to date are summarized.

Assessment of Radioactivity Concentration in Soil of some Mining

African Journals Online (AJOL)

ABSTRACT. A study was conducted to determine 226Ra, 232Th, and 40K natural activity concentrations in surface soils/sediments of some mining areas in Central Nasarawa State Nigeria, using. Sodium Iodide-Thallium Gamma Spectroscopy. Seven major sites were identified from the highly mining areas of the zone.

Determination of the emanation coefficient of radon for the South Karelia soil

Energy Technology Data Exchange (ETDEWEB)

Filimonov, V V

1975-01-01

Measurements have been obtained for so-called 'reference' plots which are used for the calibration of airborne gamma-spectrometric instruments - in all about 200 spot observations, not counting the results of continuous survey taken while in motion. The gamma-spectrometric measurements were carried out taking into account as far as possible a number of disturbing factors, such as the fluctuations in soil moisture, atmospheric precipitation, variations in the atmospheric radon concentration due to the temperature inversions.

Contamination of soil and food with radionuclides from Chernobyl

International Nuclear Information System (INIS)

Bikit, I.; Slivka, J.; Veskovic, M.; Conkic, Lj.; Krmar, M.

2004-01-01

The results of systematic gamma spectroscopic analyses of fission products performed on the territory of SAP Vojvodina after the Chernobyl accident are presented. Samples of soil grass and food were periodically taken at 5 representative locations and the regions of highest activity concentration are identified on the basis of the results obtained. In the controlled chain soil-plants (feeds)-cow's (milk) on three characteristic locations (soil with different physico-chemical and mechanical properties) the activity concentration of fission radionuclides was determined and transfer factors for soil-plants; feed-milk were calculated. At the territory of hunting sites of SAP Vojvodina, artificial radionuclides were determined in meat and bones of fallow-deer, deer, boar and wild hare; and the highest content of radionuclides was found in meat and bones of boar. (author)

Assessment of soil contamination in area surrounding Tuwaitha nuclear facilities

International Nuclear Information System (INIS)

Al-Taii, A.A.F.; AI-Jobori, S.H.; Al-Maadhidi, J.F.

2012-01-01

The wide spread looting of the Tuwaitha Nuclear Facilities as well as damaging of some buildings in 2003, had offered possibilities of contamination of soil environment inside the Site. The objective of the present work was to investigate soil contamination to help in future decontamination programs. A total of 25 soil surface samples (including one reference sample) covered different locations in the Site were collected in March 2011. High purity Ge detector was used for gamma spectrometry of soil samples. Data of total and spectral gamma for U series, Th series, 40 K and 137 Cs are presented. Slight variations were observed in specific activity of the U series 214 Bi or 214 Pb and 226 Ra among measured soil samples where the range was 10.3-12.7 for 214 Bi as compared with 12.2-33.4 Bq/kg for 226 Ra. Values of both 214 Bi and 226 Ra are in the range of reference sample specific activity indicating that no evidence of contamination had occurred in the investigated area. Results of activity concentrations of thorium series 228 Ac or 208 Tl, 212 Pb, and 212 Bi are in the range of reference sample and close to those values given worldwide for natural uranium in soil. The levels of 40 K in soil are within the natural abundance of this isotope in the soil where the range was 207.6-266.1 with 220.3 Bq/kg for the reference sample. On the other hand, 137 Cs specific activities showed great variation among measured samples. The minimum value for 137 Cs was 0.6 and the maximum 7.6 compared with 0.8 Bq/kg for the control soil sample. The non-uniformity of radioactivity concentration of 137 Cs suggest the presence of contamination in some locations although this level is considered as an acceptable level and no hazardous effect will be generated.

Natural radionuclides in mangrove soils from the State of Pernambuco, Brazil

International Nuclear Information System (INIS)

Paiva, J.D.S. de; Sousa, E.E.; Farias, E.E.G. de; Carmo, A.M.; Souza, E.M.; Franca, E.J. De

2016-01-01

Mangroves are essential for protecting coastal environments and biodiversity; however few studies encompass the distribution of radionuclides in soils from these ecosystems. By applying high resolution gamma-ray spectrometry, natural radionuclides were quantified in soils from the Chico Science Mangrove and Rio Formoso Mangrove (RFM), areas subjected to different human impacts. The activity concentrations of 226 Ra and 228 Ra were quite similar for the mangroves despite the differences found for 40 K. Moreover, no correlation with the environmental impacts on the mangroves was observed, although RFM soil was 40 K-enriched compared to deep sediments from other estuaries in the world. (author)

Determination of microelement distribution in different components of soil-plant system

International Nuclear Information System (INIS)

Luu Viet Hung; Maslov, O.D.; Gustova, M.V.; Trinh Thi Thu My; Phung Khac Nam Ho

2011-01-01

Leaves, stem, and roots of two shrub types: tea (Camellia sinensis), sweet leaf (Sauropus androgynus) and two herb types: vetiver grass (Vetiveria zizanioides L.Nash), maize (Zea mays L) and Thucuc soil where the plants grow, were collected to be studied. Contents of 22 elements in the samples were determined by three methods: XRFA (X-Ray Fluorescence Analysis), GAA (Gamma Activation Analysis), and tracking method to study distribution of these elements in plants and soil-plant relationship. The study was carried out at the Flerov Laboratory of Nuclear Reactions, JINR, Dubna. Distribution of the elements in the soil-plant system was studied

The deployment of an innovative real-time radiological soil characterization system

International Nuclear Information System (INIS)

Allen, David; Danahy, Raymond; Laird, Gregory; Seiller, Dale; White, Joan; Janke, Robert

2000-01-01

Fluor Fernald Inc., in conjunction with partners from Argonne National Laboratory, the Department of Energy's Environmental Measurements Laboratory, and Idaho National Engineering and Environmental Laboratory, has developed a program for characterizing radiological contaminants in soil in real time. The soil characterization system in use at the Fernald Environmental Management Project (FEMP) for over three years combines gamma ray spectrometry equipment with other technologies to produce a system that can scan large areas of ground and produce color coded maps which display quantitative information regarding isotopic contamination patterns. Software running on a battery powered lap-top computer, is used to control acquisition of gamma spectral data to link the spectral Information with precise detector position measurements from Global Positioning System (GPS) satellites, and to control transmission of data to a central station or van via a wireless Ethernet link where Surfer6 mapping software is used to produce maps showing the position and amount of each target analyte. Either sodium iodide (NaI) gamma ray detectors mounted on three different vehicles for mobile measurements or stationary tripod-mounted hyper-pure germanium (HPGe) detectors can be used in this system to radiologically characterize soil. The operational and performance characteristics, as well as the strengths and limitations of each of these units, will be described. The isotopic information generated by this system can be made available to remediation project mangers within an hour after the completion of a scan to aid in determination of excavation footprints, segregation of contaminated soil and verification of contamination removal. The immediate availability of radiological characterization data made possible by this real-time scanning system has allowed Fluor Fernald to accelerate remediation schedules and reduce costs by avoiding excavation delays and expensive and time consuming

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

International Nuclear Information System (INIS)

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

2016-01-01

Geological characteristics can have impacts on societal development by, e.g., geotechnical issues and radiological hazard levels. Due to urban sprawl, there is an increasing need for detailed geological assessment. In this work are analysed data from portable handheld gamma-ray spectra (K, eU and eTh) obtained in granitic and Silurian metaclastic outcrops as well as in an profile, roughly N–S, on soil covered terrains transecting a mapped contact between these rock types (the profile's northern extremity is at locations mapped as granite). Estimations from gamma-ray spectra were studied by univariate and multivariate analyses. K, eU and eTh values were higher on granite in relation to Silurian metaclastic rocks. The northern extremity of the profile showed clearly higher contents of eTh and this contrast was supported by univariate statistical tools (normality plot and Wilk–Shapiro test; boxplots). A ternary plot with the contribution of the elements to gamma-ray absorbed dose showed the separation of granite from Silurian metaclastic rocks with the former being nearer the eTh vertex. The points in the northern extremity of the profile are nearer the eTh vertex than the other points on the profile. These visual suggestions were supported by hierarchical cluster analysis, which was able to differentiate between granite and metaclastic outcrops and separate portions of the profile located on different terrains. Portable gamma-ray spectrometry showed, hence, the potential to distinguish granite and metaclastic terrains at a scale useful for engineering works. These results can also be useful for a first comparative zoning of radiological hazards (which are higher for granite). - Highlights: • Contents of K, eU and eTh were estimated by portable gamma-ray spectra. • Spectra were acquired on a profile across a soil covered granite/metaclastic contact. • Spectra were also collected on granite and Silurian metaclastic outcrops. • Obtained estimations were

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

Energy Technology Data Exchange (ETDEWEB)

Winkelmann, I

1994-12-31

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

The forming of the complexes of soil mezofauna in the zone of radioactive contamination

International Nuclear Information System (INIS)

Maksimova, S.L.

2002-01-01

We carried out the pedobiological research in the different biogeocenoses in the zone of radioactive contamination. Based on the obtained data we can conclude a direct correlation between the viability of the soil invertebrates and the background gamma-radiation intensity. All the facts indicate that soil animal complexes in biogeocenoses exposed to radiation for a long time impact clearly noticeable suppression

Measurement of K40 in mine soil

International Nuclear Information System (INIS)

Salazar R, A. R.; Vega C, H. R.

2014-10-01

The natural radioactivity of the soil and the external exposition of the gamma radiation mainly depend of the geologic characteristics of the same soil. Their radioactivity levels provide information of the radio-nuclides distribution in the environment and allow estimating the radiological risk. For this reason, the objective of this work was to determine the K 40 concentration in four soil samples of a mine that produces Ag, Pb, Cu, and Zn, in Zacatecas State (Mexico), through gamma rays spectrometry using a Sodium Iodide detector doped with Thallium (Nal (Tl)). The results it was found that the soil sample contaminated by the liquid effluents of the mine it has a specific activity of 353 Bq/kg, for draw Los Angeles of 55 Bq/kg, in the old dam of 307 Bq/kg and inside the mine of 485 Bq/kg, mentioning that all the sites refer to the same mine. Using a conversion factor of 0.043 n Gy/h (Bq/kg) -1 to calculate the absorbed dose in air of the natural radionuclide as the K 40 in the soil samples were founded the following dose reasons; of 15.18 n Gy/h, 2.37 n Gy/h, 13.2 n Gy/h and 20.86 n Gy/h, respectively. These results are similar to those reported for soil samples of Texas (USA), Karabuk (Turkey) and Kalpakkam (India), it should be noted that these samples are not mine samples; only were used like reference for this work. Our results are in an average of 300 Bq/kg that corresponds to one dose reason of 12.9 n Gy/h, comparing it with the highest value reported in the case of Chinese that is of 580 Bq/kg (24.94 n Gy/h) throwing a difference of 48.3% and compared with the smallest average value that belongs to Tripoli (Libya) of 270 Bq/kg (11.61 n Gy/h) is of 10%. The concentration average of the K 40 activity was below the world average of absorbed dose, which is of 55 n Gy/h of the average reported for the world, therefore these results can be used as a reference for the radioactivity analysis in the soil of this mine. (Author)

Rapid assay of plutonium in soils by passive L x-ray counting

International Nuclear Information System (INIS)

Gehrke, R.J.; Putnam, M.H.; Goodwin, S.G.; Kynaston, R.L.

1992-05-01

A technique has been developed to rapidly measure the presence of plutonium in soils, filters, smears, and glass waste forms by measuring the uranium L-shell x-ray emissions associated with the decay of plutonium. In addition, the technique can simultaneously acquire spectra of samples and automatically analyze them for the amount of americium, and gamma-ray emitting activation and fission products present. The samples are counted with a large area, thin-window, n-type Ge spectrometer which is equally efficient for the detection of low energy x-rays (>10 key), as well as high-energy gamma rays (>1 MeV). A 8192-channel analyzer is used to acquire the entire photon spectrum at one time. A dual-energy, time-tagged pulser, that is injected into the test input of the preamplifier to monitor the energy scale, detector resolution, and pulse pile-up will be installed in FY-92. The L x-ray portion of each spectrum is analyzed by a linear least-squares spectral fitting technique originally developed for the analysis of spectra from NaI(Tl) detectors. The gamma-ray portion of each spectrum is analyzed by a standard Ge gamma-ray analysis package. Detection limits (also referred to as lower limits of detection) for plutonium in contaminated soils that have been achieved by this technique are reported

Relationship of soil terrestrial radionuclide concentrations and the excess of lifetime cancer risk in western Mazandaran Province, Iran.

Science.gov (United States)

Abbaspour, M; Moattar, F; Okhovatian, A; Kharrat Sadeghi, M

2010-12-01

The main goal of this study is to lay out the map of the soil radionuclide activity concentrations and the terrestrial outdoor gamma dose rates in the western Mazandaran Province of Iran, and to present an evaluation scheme. Mazandaran Province was selected due to its special geographical characteristics, high population density and the long terrestrial and aquatic borders with the neighbouring countries possessing nuclear facilities. A total of 54 topsoil samples were collected, ranging from the Nour to Ramsar regions, and were based on geological conditions, vegetation coverage and the sampling standards outlined by the International Atomic Energy Agency. The excess lifetime cancer risks (ELCRs) were evaluated and the coordinates of sampling locations were determined by the global positioning system. The average terrestrial outdoor gamma dose rate was 612.38 ± 3707.93 nGy h(-1), at 1 m above the ground. The annual effective gamma dose at the western part of Mazandaran Province was 750 μSv, and the ELCR was 0.26 × 10(-2). Soil samples were analysed by gamma spectrometry with a high-purity germanium detector. The average (226)Ra, (232)Th, (40)K and (137)Cs activities were 1188.50 ± 7838.40, 64.92 ± 162.26, 545.10 ± 139.42 and 10.41 ± 7.86 Bq kg(-1), respectively. The average soil radionuclide concentrations at the western part of Mazandaran Province were higher than the worldwide range. The excess lifetime risks of cancer and the annual effective gamma doses were also higher than the global average.

Cross-Section of Hadron Production in $\\gamma\\gamma$ Collisions at LEP

CERN Document Server

Acciarri, M; Aguilar-Benítez, M; Ahlen, S P; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alverson, G; Alviggi, M G; Ambrosi, G; Anderhub, H; Andreev, V P; Angelescu, T; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Baksay, L; Banerjee, S; Banerjee, Sw; Banicz, K; Barczyk, A; Barillère, R; Barone, L; Bartalini, P; Baschirotto, A; Basile, M; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Bhattacharya, S; Biasini, M; Biland, A; Bilei, G M; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böck, R K; Böhm, A; Boldizsar, L; Borgia, B; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brigljevic, V; Brock, I C; Buffini, A; Buijs, A; Burger, J D; Burger, W J; Busenitz, J K; Button, A M; Cai, X D; Campanelli, M; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Castellini, G; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada-Canales, M; Cesaroni, F; Chamizo-Llatas, M; Chang, Y H; Chaturvedi, U K; Chekanov, S V; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chéreau, X J; Chiefari, G; Chien, C Y; Cifarelli, Luisa; Cindolo, F; Civinini, C; Clare, I; Clare, R; Cohn, H O; Coignet, G; Colijn, A P; Colino, N; Commichau, V; Costantini, S; Cotorobai, F; de la Cruz, B; Csilling, Akos; Dai, T S; D'Alessandro, R; De Asmundis, R; Degré, A; Deiters, K; Della Volpe, D; Denes, P; De Notaristefani, F; DiBitonto, Daryl; Diemoz, M; Van Dierendonck, D N; Di Lodovico, F; Dionisi, C; Dittmar, Michael; Dominguez, A; Doria, A; Dova, M T; Duchesneau, D; Duinker, P; Durán, I; Dutta, S; Easo, S; Efremenko, Yu V; El-Mamouni, H; Engler, A; Eppling, F J; Erné, F C; Ernenwein, J P; Extermann, Pierre; Fabre, M; Faccini, R; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, Marta; Fenyi, B; Ferguson, T; Ferroni, F; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisk, I; Forconi, G; Fredj, L; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gau, S S; Gentile, S; Gheordanescu, N; Giagu, S; Goldfarb, S; Goldstein, J; Gong, Z F; Gougas, Andreas; Gratta, Giorgio; Grünewald, M W; Gupta, V K; Gurtu, A; Gutay, L J; Hartmann, B; Hasan, A; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Van Hoek, W C; Hofer, H; Hong, S J; Hoorani, H; Hou, S R; Hu, G; Innocente, Vincenzo; Jenkes, K; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Kasser, A; Khan, R A; Kamrad, D; Kamyshkov, Yu A; Kapustinsky, J S; Karyotakis, Yu; Kaur, M; Kienzle-Focacci, M N; Kim, D; Kim, D H; Kim, J K; Kim, S C; Kim, Y G; Kinnison, W W; Kirkby, A; Kirkby, D; Kirkby, Jasper; Kiss, D; Kittel, E W; Klimentov, A; König, A C; Kopp, A; Korolko, I; Koutsenko, V F; Krämer, R W; Krenz, W; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lapoint, C; Lassila-Perini, K M; Laurikainen, P; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Leonardi, E; Levchenko, P M; Li Chuan; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lu, W; Lü, Y S; Lübelsmeyer, K; Luci, C; Luckey, D; Luminari, L; Lustermann, W; Ma Wen Gan; Maity, M; Majumder, G; Malgeri, L; Malinin, A; Maña, C; Mangeol, D J J; Mangla, S; Marchesini, P A; Marin, A; Martin, J P; Marzano, F; Massaro, G G G; McNally, D; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Von der Mey, M; Mi, Y; Mihul, A; Van Mil, A J W; Mirabelli, G; Mnich, J; Molnár, P; Monteleoni, B; Moore, R; Morganti, S; Moulik, T; Mount, R; Müller, S; Muheim, F; Muijs, A J M; Nahn, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Niessen, T; Nippe, A; Nisati, A; Nowak, H; Oh, Yu D; Opitz, H; Organtini, G; Ostonen, R; Palomares, C; Pandoulas, D; Paoletti, S; Paolucci, P; Park, H K; Park, I H; Pascale, G; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Peach, D; Pei, Y J; Pensotti, S; Perret-Gallix, D; Petersen, B; Petrak, S; Pevsner, A; Piccolo, D; Pieri, M; Pinto, J C; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Postema, H; Produit, N; Prokofev, D; Prokofiev, D O; Rahal-Callot, G; Raja, N; Rancoita, P G; Rattaggi, M; Raven, G; Razis, P A; Read, K; Ren, D; Rescigno, M; Reucroft, S; Van Rhee, T; Riemann, S; Riles, K; Robohm, A; Rodin, J; Roe, B P; Romero, L; Rosier-Lees, S; Rosselet, P; Van Rossum, W; Roth, S; Rubio, Juan Antonio; Ruschmeier, D; Rykaczewski, H; Salicio, J; Sánchez, E; Sanders, M P; Sarakinos, M E; Sarkar, S; Sassowsky, M; Schäfer, C; Shchegelskii, V; Schmidt-Kärst, S; Schmitz, D; Schmitz, P; Scholz, N; Schopper, Herwig Franz; Schotanus, D J; Schwenke, J; Schwering, G; Sciacca, C; Sciarrino, D; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shukla, J; Shumilov, E; Shvorob, A V; Siedenburg, T; Son, D; Sopczak, André; Smith, B; Spillantini, P; Steuer, M; Stickland, D P; Stone, A; Stone, H; Stoyanov, B; Strässner, A; Strauch, K; Sudhakar, K; Sultanov, G G; Sun, L Z; Susinno, G F; Suter, H; Swain, J D; Tang, X W; Tauscher, Ludwig; Taylor, L; Ting, Samuel C C; Ting, S M; Tonutti, M; Tonwar, S C; Tóth, J; Tully, C; Tuchscherer, H; Tung, K L; Uchida, Y; Ulbricht, J; Uwer, U; Valente, E; Van de Walle, R T; Vesztergombi, G; Vetlitskii, I; Viertel, Gert M; Vivargent, M; Völkert, R; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Vorvolakos, A; Wadhwa, M; Wallraff, W; Wang, J C; Wang, X L; Wang, Z M; Weber, A; Wittgenstein, F; Wu, S X; Wynhoff, S; Xu, J; Xu, Z Z; Yang, B Z; Yang, C G; Yao, X Y; Ye, J B; Yeh, S C; You, J M; Zalite, A; Zalite, Yu; Zemp, P; Zeng, Y; Zhang, Z; Zhang, Z P; Zhou, B; Zhu, G Y; Zhu, R Y; Zichichi, Antonino; Ziegler, F

1997-01-01

The reaction $\\mathrm{e}^{+} \\mathrm{e}^{-} \\rightarrow \\mathrm{e}^{+} \\mathrm{e}^{-} \\gamma ^{*} \\gamma ^{*} \\rightarrow \\mathrm{e}^{+} \\mathrm{e}^{-} $ {\\sl hadrons} is analysed using data collected by the L3 detector during the LEP runs at $\\sqrt {s}$ = 130-140 GeV and $\\sqrt {s}$ = 161 GeV. The cross sections $\\sigma(\\mathrm{e}^{+} \\mathrm{e}^{-} \\rightarrow \\mathrm{e}^{+} \\mathrm{e}^{-} $ {\\sl hadrons}) and $\\sigma (\\gamma\\gamma \\rightarrow $ {\\sl hadrons}) are measured in the interval 5 $\\leq W_{\\gamma\\gamma} \\leq$ 75 GeV. The energy dependence of the $\\sigma (\\gamma\\gamma \\rightarrow $ {\\sl hadrons}) cross section is consistent with the universal Regge behaviour of total hadronic cross sections. %\\end{abstract}

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

International Nuclear Information System (INIS)

Gasser, Estelle

2014-01-01

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

Radio biogeochemical assessment of the soil near the Issyk-Kul region

International Nuclear Information System (INIS)

Kaldybaev, B.; Djenbaev, B.

2014-01-01

Full text : Soil is one of the main natural resources, providing for the sustainable development of the country. For environmentally well founded and balanced use and protection of land resources it is necessary to create the optimal structure of arable farming, minimizing negative impacts on the land of diverse of agricultural activities. Determination of chemical elements in the soil was conducted by the methods of X-ray fluorescence analysis and radionuclide by the methods of instrumental gamma spectrometry

Neutron moisture gaging of agricultural soil

International Nuclear Information System (INIS)

Pospisil, S.; Janout, Z.; Kovacik, M.

1987-01-01

The design is described of a neutron moisture gage which consists of a measuring probe, neutron detector, small electronic recording device and a 241 Am-Be radionuclide source. The neutron detector consists of a surface barrier semiconductor silicon detector and a conversion layer of lithium fluoride. The detection of triton which is the reaction product of lithium with neutrons by the silicon detector is manifested as a voltage pulse. The detector has low sensitivity for fast neutrons and for gamma radiation and is suitable for determining moisture values in large volume samples. Verification and calibration measurements were carried out of chernozem, brown soil and podzolic soils in four series. The results are tabulated. Errors of measurement range between 0.8 to 1.0%. The precision of measurement could be improved by the calibration of the device for any type of soil. (E.S.). 4 tabs., 6 refs., 5 figs

Radioactivity analysis of sounai region by gamma spectrometry and radiation monitoring network

International Nuclear Information System (INIS)

El-Mongy, S.A.; Abd El-Aziz, N.; El-Tahawy, M.S.; Morsy, S.

2000-01-01

Levels of natural and man-made radioactivity in soil and plant of southern sinai region are investigated by using Gamma- spectrometric analysis. The found average concentrations of 2 26Ra ( 2 38U) series, 2 32Th series and 4 0K are 20.2, 17.0 and 378.8 Bq/Kg respectively. The fall out 1 37Cs is the only man-made radionuclide detected with concentrations not exceed 3 Bq/Kg (dry weight) in both soil and plant samples. The effective dose rate equivalent are 106, 129, 114 and 104 n Sv/h for El-Tour, Sharm El-Shaik, Nwuiba and Taba as detected by the corresponding stations of the national radiation monitoring network (NRMN) respectively. The radium equivalent (Req) and absorbed dose rate resulted due to the natural radionuclides in soil are also calculated and given

Gamma Knife

Science.gov (United States)

... News Physician Resources Professions Site Index A-Z Gamma Knife Gamma Knife® is a radiation therapy that uses computerized ... If you're scheduled for radiation therapy using Gamma Knife®, a treatment team consisting of a radiation ...

Formulation of the relationship between indices of neutron-gamma and gamma-gamma method and the percentrage of iron

International Nuclear Information System (INIS)

Majorowicz, J.

1973-01-01

In this article, the author presents the possibility of a complex utilization of radiometric logging methods, neutron-gamma profiling and gamma-gamma density logging for determining percentage of iron and establishing geophysical possibilities of identifying zones of economically profitable ores in borehole profiles. Figures present the correlations between indices of neutron-gamma and gamma-gamma logging methods and the percentage of iron, as well as the correlation of neutron-gamma and gamma-gamma indices for zones minerallized with iron ores. The article presents the correlational analyses of the results: the correlational coefficients are given as well as total error in determining iron content on the basis of each of the methods described. Next, a multidimensional statistical analysis is carried out on the results obtained. On the basis of the two-dimensional correlational coefficients calculated and the average standard deviation, an equation of linear regression was formulated, simultaneously involving three parameters - the indices of neutron-gamma and gamma-gamma logging and the percentage of iron. The multiple correlational coefficient obtained markedly exceeds the two-dimentional correlation coefficient (r=0.974>rsub(xz)>rsub(yz)>rsub(xy)). The given method of utilizing multidimensional statistics in borehole geophysics for identifying iron ores is an efficient one. On the basis of several relationships among independent variables which are less obvious (smaller values of correlational coefficient), it is possible to obtain a single distinct relationship involving all variables simultaneously. (author)

Determination of Radium transfer factor from soil to vegetables by Gamma spectrometry in high levels of natural radiation areas of Ramsar

International Nuclear Information System (INIS)

Reza-nejad, F.

2000-01-01

One of the most important and prevalent radioactive contaminants in the environment is radium-226 from uranium-238 decay series. This radionuclide after entering in to the food chain, especially through consumed drinking water and vegetables is transferred to man. In order to determine the transfer factor of 226 Ra from soil to veg tables and to assess the effective dose due to ingestion of vegetables by the critical group of Talesh-Mahaleh which is one of the high levels natural radiation areas of Ramsar, more than 90 samples of soil, seed and vegetable were collected and analysed by gamma spectrometry using a High Purity Germanium detector coupled to a Canberra Mca-series 100. The concentrations of 226 Ra were determined by 609 KeV photopeak of bismuth-214 in secular equilibrium with 226 Ra. Concentrations of 226 Ra in dried soil samples were ranged from a minimum of 733 ± 25 to a maximum of 45100 ± 37 Bq Kg -1 . The maximum and minimum transfer factor of 226 Ra were determined in leafy and root vegetables respectively. The average transfer factor of 226 RA were calculated 1.2 * 10 -2 for all 14 kind of vegetables. The results indicated that by increasing the 226 Ra concentration in substrate, the uptake of this radionuclide has exponentially increased while, the transfer factors were decreased. Also there is a positive correlation between uptake of 226 Ra and Ca in vegetable. The highest and lowest ratio of 226 Ra/Ca were measured 127.8 Bq Kg -1 and 8 Bq Kg -1 and 8 Bq Kg -1 in carrot and tomato samples respectively. The effective dose resulting from 226 Ra due to consumption of vegetables for critical group was 51.6 μ Sv a -1 which is 13 times more than average of effective dose resulting from this radionuclide due to intake of all kind of foods and water in background region

Assessment of radioactivity concentration in soil of some mining ...

African Journals Online (AJOL)

A study was conducted to determine 226Ra, 232Th, and 40K natural activity concentrations in surface soils/sediments of some mining areas in Central Nasarawa State Nigeria, using Sodium Iodide-Thallium Gamma Spectroscopy. Seven major sites were identified from the highly mining areas of the zone and a total of ...

Natural environmental radioactivity and estimation of radiation exposure from saline soils

International Nuclear Information System (INIS)

Akhtar, N.; Tufail, M.; Ashraf, M.

2005-01-01

The study was conducted for the investigation of amount of radioactivity in the barren and cultivated soil of Bio saline Research Station in Pakka Anna, established by Nuclear Institute for Agriculture and Biology in 1990, 34 km. away from the city of Faisalabd, in the Punjab Province of Pakistan. The studies were done on an area of about 100 hectares of two types of virgin and fertilized saline soils. The technique of gamma ray spectrometry was applied using High Purity Germanium gamma ray detector and a P C based MCA. Activity concentration levels due to 40 K, 137 Cs, 226 Ra and 232 Th were measured in 250 saline soil samples collected at a spacing of about 4 hectares at the depth level of 0-25 cm. with a step of 5 cm. depth. Activity concentration ranges of the concerned radionuclides for both of the soils were as follows: 40 K, for virgin and cultivated saline soil was 500-610.2 and Bq/kg 560.2-635.6 respectively; 137 Cs, 3.57-3.63 and 1.98-5.15 Bq/kg 238 U, 26.3-31.6 and 30.6-38.7 Bq/kg, and 232 Th, 50.6-55.3 and 50.6-64.0 Bq/kg respectively. The absorbed dose rate in air lies in the region 63-73 nGyh -1 and 68-83 nGyh -1 for virgin and fertilized soils respectively. This indicates that this region lies in the area of higher radiation background, while comparing with the worlds' average. The slightly higher value of dose in the fertilized farm may be due to the use of fertilizers for cultivation. Before the radiometric measurements, chemical analysis for concentration of Na, Ca and Mg was also carried out along with the measurement of electrical conductivity and p H of the soil samples

Comparative uptake of gamma-emitting fission product nuclides by plants

International Nuclear Information System (INIS)

D'souza, T.J.; Mistry, K.B.

1974-01-01

The comparative uptake of long-lived gamma-emitting fission product nuclides 106 Ru, 125 Sb, 137 Cs and 144 Ce, present in global fallout from nuclear explosions, by maize (Zea mays L) plants was examined in water culture experiments. Over identical duration of plant growth, the extent of accumulation of the radionuclides in aerial tissues was in the following decreasing order: 137 Cs >, 125 Sb >, 106 Ru > and 144 Ce. In roots, however, the retention of 144 Ce and 106 Ru was greater than that of 137 Cs and 125 Sb. Complementary studies with maize and rice (Oryza sativa L) grown on two contrasting soil types, namely, laterite and black clay loam indicated that 137 Cs uptake by plants was markedly greater than that of the other radionuclides in both soil types. Plant uptake of 106 Ru and 125 Sb was significantly higher than that of 144 Ce in the black soil. In the laterite, however, 144 Ce uptake far exceeded that of 106 Ru and 125 Sb. In general, maize removed higher amounts of the radionuclides than rice from both soil types. (author)

Effects of acute gamma-irradiation on reproduction of the collembolan (Folsomia candida) in a standard laboratory test

International Nuclear Information System (INIS)

Nakamori, Taizo; Yoshida, Satoshi; Kubota, Yoshihisa; Ban-nai, Tadaaki

2006-01-01

The abstract of this study was to provide data for radiological protection of the environment, the dose-effect relationship of acute gamma irradiation on the reproduction of the soil invertebrate Folsomia candida (Collembola) was studied according to a standard laboratory test. Juvenile collembolans were exposed to 137 Cs gamma-radiation at a dose range of 4-110 Gy. After four weeks' rearing, the number of neonate juveniles was compared with that of the non-irradiated control. The value of the 10% effective dose for reproduction was estimated to be 7.1 Gy. (author)

Preliminary measurements of gamma radiation in Chilean Antarctic Stations

Energy Technology Data Exchange (ETDEWEB)

Stuardo B, E. (Comision Chilena de Energia Nuclear, Santiago. Dept. de Aplicaciones Nucleares)

1983-11-01

Natural and artificial gamma radiation, 1 m above the soil, is being investigated in 4 Chilean Antartic Stations. The measurements are performed with different types of TLD detectors. Preliminary results in the Tte. Marsh Station are reported and discussed. An average exposition of 3,5 ..mu..R/h was found during a 108 days period. This exposition corresponds to an annual dose of about 40 mrad, 8% of the annual dose limit for individual of the public. The presence of low energy artificial radioisotopes was not found.

The high intensity {gamma}-ray source (HI{gamma}S) and recent results

Energy Technology Data Exchange (ETDEWEB)

Tonchev, A.P. [Duke University and TUNL, Triangle University Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 0308 (United States)]. E-mail: tonchev@tunl.duke.edu; Boswell, M. [University of North Carolina at Chapel Hill and TUNL, Chapel Hill, NC 27599 (United States); Howell, C.R. [Duke University and TUNL, Triangle University Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 0308 (United States); Karwowski, H.J. [University of North Carolina at Chapel Hill and TUNL, Chapel Hill, NC 27599 (United States); Kelley, J.H. [North Carolina State University and TUNL, Raleigh, NC 27695 (United States); Tornow, W. [Duke University and TUNL, Triangle University Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 0308 (United States); Wu, Y.K. [Duke University and Duke Free Electron Laser Laboratory, Durham, NC 27708-0319 (United States)

2005-12-15

The high intensity {gamma}-ray source (HI{gamma}S) utilizes intra-cavity backscattering of free electron laser photons from the Duke electron storage ring to produce a unique monoenergetic beam of high-flux {gamma}-rays with high polarization and selectable energy resolution. At present, {gamma}-ray beams with energies from 2 to 58 MeV are available with intensities as high as 10{sup 5}-5 x 10{sup 6} {gamma}/s, energy spreads of 3% or better, and nearly 100% linear polarization. The quality and intensity of the {gamma}-ray beams at HI{gamma}S are responsible for the unprecedented performance of this facility in a broad range of research programs in nuclear structure, nuclear astrophysics and nuclear applications. Recent results from excitation of isomeric states in ({gamma}, n) reactions and parity assignments of dipole states determined via the ({gamma}, {gamma}') reaction are presented.

Mapping natural radioactivity of soils in the eastern Canary Islands.

Science.gov (United States)

Arnedo, M A; Rubiano, J G; Alonso, H; Tejera, A; González, A; González, J; Gil, J M; Rodríguez, R; Martel, P; Bolivar, J P

2017-01-01

The Canary Islands archipielago (Spain) comprises seven main volcanic islands and several islets that form a chain extending for around 500 km across the eastern Atlantic, between latitudes 27°N and 30°N, with its eastern edge only 100 km from the NW African coast. The administrative province of Las Palmas comprises the three eastern Canary Islands (Lanzarote, Fuerteventura and Gran Canaria). An extensive study of terrestrial gamma dose rates in surface soils has been carried out to cover the entire territory of the province (4093 km 2 ). The average outdoor gamma dose rate in air at 1 m above ground is 73 nGyh -1  at Gran Canaria, 32 nGyh -1  at Fuerteventura, and 25 nGyh -1  at Lanzarote. To complete the radiological characterization of this volcanic area, 350 soil samples at 0-5 cm depth were collected to cover all the geologic typologies of the islands. These samples were measured using high resolution gamma spectrometry to determine the activity concentrations of 226 Ra, 232 Th and 40 K. The average values obtained were 25.2 Bq/kg, 28.9 Bq/kg, and 384.4 Bq/kg, respectively. Maps of terrestrial gamma activity, effective dose, and activity concentrations of 226 Ra, 232 Th and 40 K for the region have been developed through the use of geostatistical interpolation techniques. These maps are in accord with the geology of the islands. Copyright © 2016 Elsevier Ltd. All rights reserved.

Release of bound residues of atrazine from soils through autoclaving and gamma radiation sterilization

International Nuclear Information System (INIS)

Nakagawa, L.E.; Andréa, M.M.

1997-01-01

The sterilization methods are particularly important to study the influence of microorganisms on the pesticide dissipation in soils. This study, conducted in the laboratories of the Instituto Biológico of São Paulo in august 1996, tested the influence of two methods of soil sterilization - moist heat (autoclaving) and γ radiation - on the release of nonextractable or bound residues. It was studied, as example, bound residues of the herbicide atrazine in two types of soil (gley humic and dark red latosol). In the soil samples submitted to the moist heat sterilization, the recovery of the previously bound residues as reextractable residues was 5.6 and 5.9 times higher than in the control soils, not submitted to any sterilization process. Therefore, the method itself released the residues, indicating that the autoclaving is not the most appropriate method for studies on the influence of microorganisms on the release of bound residues. Otherwise, the γ radiation did not modify the residues recovery when compared to the controls. (author) [pt

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

International Nuclear Information System (INIS)

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

1995-01-01

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

Optimisation of beryllium-7 gamma analysis following BCR sequential extraction

International Nuclear Information System (INIS)

Taylor, A.; Blake, W.H.; Keith-Roach, M.J.

2012-01-01

Graphical abstract: Showing decrease in analytical uncertainty using the optimal (combined preconcentrated sample extract) method. nv (no value) where extract activities were 7 Be geochemical behaviour is required to support tracer studies. ► Sequential extraction with natural 7 Be returns high analytical uncertainties. ► Preconcentrating extracts from a large sample mass improved analytical uncertainty. ► This optimised method can be readily employed in studies using low activity samples. - Abstract: The application of cosmogenic 7 Be as a sediment tracer at the catchment-scale requires an understanding of its geochemical associations in soil to underpin the assumption of irreversible adsorption. Sequential extractions offer a readily accessible means of determining the associations of 7 Be with operationally defined soil phases. However, the subdivision of the low activity concentrations of fallout 7 Be in soils into geochemical fractions can introduce high gamma counting uncertainties. Extending analysis time significantly is not always an option for batches of samples, owing to the on-going decay of 7 Be (t 1/2 = 53.3 days). Here, three different methods of preparing and quantifying 7 Be extracted using the optimised BCR three-step scheme have been evaluated and compared with a focus on reducing analytical uncertainties. The optimal method involved carrying out the BCR extraction in triplicate, sub-sampling each set of triplicates for stable Be analysis before combining each set and coprecipitating the 7 Be with metal oxyhydroxides to produce a thin source for gamma analysis. This method was applied to BCR extractions of natural 7 Be in four agricultural soils. The approach gave good counting statistics from a 24 h analysis period (∼10% (2σ) where extract activity >40% of total activity) and generated statistically useful sequential extraction profiles. Total recoveries of 7 Be fell between 84 and 112%. The stable Be data demonstrated that the

Investigation of soil erosion in arable land in Hungary using radiotracer technique

International Nuclear Information System (INIS)

Dezsoe, Z.; Szabo, Sz.

2004-01-01

Quantitative data on long-term soil erosion rates on agricultural land are an essential requirement for the development of effective soil management and conservation strategies. Although several methods to estimate soil erosion exist, the use of 137 Cs and/or 210 Pb as fallout radionuclides for tracing soil movement overcomes many of the limitations of the traditional methods. Recently, the 137 Cs-technique has been widely accepted and is now commonly used for estimating the magnitude of soil loss. Long-term migration of 137 Cs in the Buekkzserc-Cserepfalu-Bogacs triangle area, at the foot of Buekk mountain (NE Hungary) was studied. The samples were analysed for 137 Cs by gamma spectrometry, using a calibrated high-resolution, low background HPGe coaxial detector. Migration of fallout nuclides in an undisturbed stable soil reflects the influence of a range of physico-chemical and biological processes operating in the soil system. (N.T.)

Study of {gamma}'s in Naiade; Etude des gamma de Naiade

Energy Technology Data Exchange (ETDEWEB)

Millot, J P; Rastoin, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

Following a study of the gamma sources, the flux of gamma of different energies in the swimming pool is investigated. The biological dose can thus be obtained by calculation, and compared with the results given by photographic plates. The influence of photoneutrons is estimated by calculation, and research is being carried out on their influence on the thermal neutron flux curve on the axis of the uranium plate, with the plate emitting neutrons and with the plate protected by boral. (author) [French] Apres l'etude des sources de gamma, l'on etudie le flux de gamma de differentes energies dans la piscine. La dose biologique peut etre obtenue ainsi par le calcul et comparee avec les resultats donnes par les plaques photographiques. L'influence des photoneutrons est estimee par le calcul et l'on recherche leur influence sur la courbe de flux de neutrons thermiques sur l'axe de la plaque d'uranium, la plaque emettant des neutrons et la plaque protegee par du boral. (auteur)

Measurement of K{sup {+-}}{yields}{pi}{sup {+-}}{gamma}{gamma} decays

Energy Technology Data Exchange (ETDEWEB)

Morales Morales, Cristina

2009-07-21

The goal of this thesis was an experimental test of an effective theory of strong interactions at low energy, called Chiral Perturbation Theory (ChPT). Weak decays of kaon mesons provide such a test. In particular, K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} decays are interesting because there is no tree-level O(p{sup 2}) contribution in ChPT, and the leading contributions start at O(p{sup 4}). At this order, these decays include one undetermined coupling constant, c. Both the branching ratio and the spectrum shape of K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} decays are sensitive to this parameter. O(p{sup 6}) contributions to K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} ChPT predict a 30-40% increase in the branching ratio. From the measurement of the branching ratio and spectrum shape of K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} decays, it is possible to determine a model dependent value of c and also to examine whether the O(p{sup 6}) corrections are necessary and enough to explain the rate. About 40% of the data collected in the year 2003 by the NA48/2 experiment have been analyzed and 908 K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} candidates with about 8% background contamination have been selected in the region with z=m{sup 2}{sub {gamma}}{sub {gamma}}/m{sub K}{sup 2}{>=}0.2. Using 5,750,121 selected K{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup 0} decays as normalization channel, a model independent differential branching ratio of K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} has been measured to be: BR(K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma}, z{>=}0.2)=(1.018{+-}0.038{sub stat}{+-}0.039{sub syst}{+-}0.004{sub ext}).10{sup -6}. From the fit to the O(p{sup 6}) ChPT prediction of the measured branching ratio and the shape of the z-spectrum, a value of c=1.54{+-}0.15{sub stat}{+-}0.18{sub syst} has been extracted. Using the measured c value and the O(p{sup 6}) ChPT prediction, the branching ratio for z=m{sup 2}{sub

Determination of correction and conversion factor of exposure rate generated Gamma spectrometer GR-320 to Victoreen data

International Nuclear Information System (INIS)

Supardjo-AS; Mappa, Djody-Rachim; Nasrun-Syamsul; Syamsul-Hadi

2000-01-01

Exposure rate data of Muria Peninsula were generated from Victoreen-491 measurement and calculation of radioelement content in soil which were measured by Exploranium GR-320, using IAEA formula. However those data are not be comparable so the exposure rate calculated from Gamma Spectrometer data necessarily to be corrected. The correction factor was determinate by measuring the exposure rate of at the NMDC's back yard selected location using Victoreen-491 and Gamma Spectrometer Exploranium GR-320 . Correction factor was created by comparing mean exposure rate data that calculated from 30 data measured by Gamma Spectrometer instrument and to those Victoreen's exposure rate. Conversion factor was gained from comparing of total count data of Gamma Spectrometer Exploranium GR-320 to Victoreen's exposure rate data. The correction factor of Exploranium GR-320's exposure rate is 0.34 μR/hours, and the conversion factor of total count is 0.0092 μR/hours per c/m. Deviation Victoreen 491 = 4.7 % and Gamma Spectrometer Exploranium GR-320 8.6 %

137Cs Transfer Factor from Latosol Soil to Swamp Gabbages (Ipomea Reptans Poir)

International Nuclear Information System (INIS)

Leli-Nirwani; Yurfida; Buchori

2001-01-01

A study of 137 Cs transfer factor from Latosol soil to swamp cabbages plant has been conducted using pot treatment system with complete random design. The aim of the research is to determine transfer factor of 137 Cs from latosol soil to swamp cabbages plant. Cs-137 concentration administered was 7.5287 kBq/pot. The number of swamp cabbages planted in 137 Cs treated soil and in cannot soil respectively was 12 pots filled with 1 kg soil/pot. After harvest, the weight of dried plant was measured. Transfer factor was determined according to the accumulation of 137 Cs concentration in swamp cabbages and soil and counted using Spectrometer Gamma. It was found that is a significant difference between 137 Cs concentration in swamp cabbages planted inthe treated soil and that of control soil. Transfer factor ranges between 0.02 and 0.13 with the averageof 0.08. (author)

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

Science.gov (United States)

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.

Soil structure restoration by wet/dry cycles assessed by computed tomography

Energy Technology Data Exchange (ETDEWEB)

Pires, L.F. [Univ. of Sao Paulo, Center for Nuclear Energy in Agriculture, Piracicaba, Sao Paulo (Brazil)

2005-07-01

Some studies have shown that soil structures can be restored through the sequence of wetting and drying cycles. These cycles causes changes in the soil pore system, which is very important to agriculture, because directly affect plant growth by root penetration, retention and movement of water and gases. The aim of this study was to follow by gamma-ray computed tomography (CT) the effect of soil wetting/drying process on the soil structure repairing of samples collected in cylinders. A first-generation tomograph with an {sup 241}Am source and a 7.62 x 7.62 cm NaI(Tl) scintillation crystal detector coupled to a photomultiplier tube was employed. Image analysis and tomographic unit profiles show that CT can provide an insight to sample structure restoration, which helps to have a better comprehension of soil physical hydraulic phenomena. (author)

Soil structure restoration by wet/dry cycles assessed by computed tomography

International Nuclear Information System (INIS)

Pires, L.F.

2005-01-01

Some studies have shown that soil structures can be restored through the sequence of wetting and drying cycles. These cycles causes changes in the soil pore system, which is very important to agriculture, because directly affect plant growth by root penetration, retention and movement of water and gases. The aim of this study was to follow by gamma-ray computed tomography (CT) the effect of soil wetting/drying process on the soil structure repairing of samples collected in cylinders. A first-generation tomograph with an 241 Am source and a 7.62 x 7.62 cm NaI(Tl) scintillation crystal detector coupled to a photomultiplier tube was employed. Image analysis and tomographic unit profiles show that CT can provide an insight to sample structure restoration, which helps to have a better comprehension of soil physical hydraulic phenomena. (author)

Measurement and Analysis of Specific Activities of 238U, 232Th,226Ra, 40K and 137Cs in Soil Samples from Phatthalung Province (Thailand) using Gamma Ray Spectrometry

International Nuclear Information System (INIS)

Daoh, Murnee; Kessaratikoon, Prasong; Udomsomporn, Suchin

2011-06-01

Full text: Specific activity of natural (238 U , 232 T h, 226 R a and 40 K ) and anthropogenic radionuclide (137 C s) in 109 soil samples collected from 11 districts in Phathalung province have been measured and analyzed. Experimental results were obtained by using a high purity germanium (HPGe) detector and gamma spectrometry analysis system at Nuclear and Material Physics laboratory in Department of Physics Faculty of Science Thaksin University Songkhla Campus. Gamma ray radioactive standard sources 60 C o, 137 C s and 133 B a were used to calibrate the measurement system. The KCl and two reference materials (RGU-1 and RGTh-1) obtained from the International Atomic Energy Agency were also used to analyze and compute the 40 K , 238 U (or 226 R a) and 232 T h specific activity in all soil samples. The IAEA/SL-2 was also used to evaluate the specific activity of 137 C s in all soil samples. The measuring time of each sample was 10,800 seconds. It was found that specific activity ranged from 148.17 to 11276.78 Bq/kg for 40 K , 58.29 to 518.45 Bq/kg for 226 R a, 8.40 to 236.19 Bq/kg for 232 T h and 0.00 tp 12.39 Bq/kg for 137 C s with mean values of 3573.35 ± 203.89 Bq/kg, 135.89 ± 6.71 Bq/kg, 76.34 ± 5.32 Bq/kg and 1.05 ± 0.70 Bq/kg respectively. Furthermore, absorbed dose rate in air (D), radium equivalent activity (Ra e q), external hazard index (H e x), and annual effective dose rate (AEDout) of this area were also evaluated by using the mean values of specific activities of the 40 K , 226 R a and 232 T h. Moreover, the experimental results were also compared with Office of Atoms for Peace (OAP) research data, Thailand and global radioactivity measurement and evaluations. The radioactive contour maps of specific activities of natural and anthropogenic radionuclides from this study were created by using the program ArcGis Version 9.2

Bulk density of an alfisol under cultivation systems in a long-term experiment evaluated with gamma ray computed tomography

International Nuclear Information System (INIS)

Bamberg, Adilson Luis; Silva, Thiago Rech da; Pauletto, Eloy Antonio; Pinto, Luiz Fernando Spinelli; Lima, Ana Claudia Rodrigues de; Timm, Luis Carlos

2009-01-01

The sustainability of irrigated rice (Oryza sativa L.) in lowland soils is based on the use of crop rotation and succession, which are essential for the control of red and black rice. The effects on the soil properties deserve studies, particularly on soil compaction. The objective of this study was to identify compacted layers in an albaqualf under different cultivation and tillage systems, by evaluating the soil bulk density (Ds) with Gamma Ray Computed Tomography (TC). The analysis was carried out in a long-term experiment, from 1985 to 2004, at an experimental station of EMBRAPA Clima Temperado, Capao do Leao, RS, Brazil, in a random block design with seven treatments, with four replications (T1 - one year rice with conventional tillage followed by two years fallow; T2 - continuous rice under conventional tillage; T4 - rice and soybean (Glycine Max L.) rotation under conventional tillage; T5 - rice, soybean and corn (Zea maize L.) rotation under conventional tillage; T6 - rice under no-tillage in the summer in succession to rye-grass (Lolium multiflorum L.) in the winter; T7 - rice under no-tillage and soybean under conventional tillage rotation; T8 - control: uncultivated soil). The Gamma Ray Computed Tomography method did not identify compacted soil layers under no tillage rice in succession to rye-grass; two fallow years in the irrigated rice production system did not prevent the formation of a compacted layer at the soil surface; and in the rice, soybean and corn rotation under conventional tillage two compacted layers were identified (0.0 to 1.5 cm and 11 to 14 cm), indicating that they may restrict the agricultural production in this cultivation system on Albaqualf soils. (author)

Measurement of ²²⁶Ra in soil from oil field: advantages of γ-ray spectrometry and application to the IAEA-448 CRM.

Science.gov (United States)

Ceccatelli, A; Katona, R; Kis-Benedek, G; Pitois, A

2014-05-01

The analytical performance of gamma-ray spectrometry for the measurement of (226)Ra in TENORM (Technically Enhanced Naturally Occurring Radioactive Material) soil was investigated by the IAEA. Fast results were obtained for characterization and certification of a new TENORM Certified Reference Material (CRM), identified as IAEA-448 (soil from oil field). The combined standard uncertainty of the gamma-ray spectrometry results is of the order of 2-3% for massic activity measurement values ranging from 16500 Bq kg(-1) to 21500 Bq kg(-1). Methodologies used for the production and certification of the IAEA-448 CRM are presented. Analytical results were confirmed by alpha spectrometry. The "t" test showed agreement between alpha and gamma results at 95% confidence level. © 2013 Published by Elsevier Ltd.

Gamma ray generator

Science.gov (United States)

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.

Detection of irradiation induced changes on the activity and diversity of soil organisms: the effect of soil type

International Nuclear Information System (INIS)

Parekh, N.R.; Beresford, N.A.; Black, H.I.J.; Potter, E.D.; Poskitt, J.M.; Dodd, B.A.

2004-01-01

Whilst non-radiological environmental impact assessments consider impacts on ecosystem function by assessing soil health the techniques of doing so have rarely been applied to radiological studies. Our aim in the study described was to measure the effects of irradiation treatments on soil communities from three different soils. Undisturbed soil cores from two temperate woodland sites (deciduous and coniferous) and a grassland site were irradiated to give a range of cumulative doses from 0 160 Gy. All cores were incubated at 15 deg C and three cores from each treatment sampled after <1, 3 and 8 days post irradiation. Soil samples were analysed for the presence and abundance of fauna, fungi and heterotrophic bacteria. The activity and functional diversity of soil microbial communities was also assessed in terms of their potential to utilise a range of carbon sources. There was a small impact on Oribatid mites at the highest dose but no significant effect on other soil faunal groups. Although significant changes in the numbers of cultivable fungi or fast growing heterotrophic bacteria were not observed at any of the treatment doses, the numbers of cultivable Pseudomonas spp. declined in all three soil types after irradiation at 80 and 160 Gy. This decline was greatest in the coniferous forest soil. Microbial communities from this soil also showed a dramatic decrease in metabolic activity and in the number of substrates utilised after irradiation at 160 Gy as compared with control non-irradiated samples. Our results show that the affects of gamma irradiation on soil microorganisms are more pronounced in the two organic forest soils as compared to the mineral grassland soil. These differences can be related to two factors; variations in the physico-chemical shielding properties of the soils and differences in the indigenous communities in terms of radioresistant species. (author)

Gamma-spectrometric surveys in differentiated granites. I: a review of the method and of the geochemical behavior of K, Th and U

International Nuclear Information System (INIS)

Ulbrich, Horstpeter Herberto Gustavo Jose; Ulbrich, Mabel Norma Costas; Guimaraes, Gilson Burigo

2009-01-01

This contribution is part of a research project on the Neo proterozoic Cunhaporanga Granitic Complex (CGC), cropping out in the Ponta Grossa Arch (Parana state, SE Brazil). An initial study used the gamma-spectrometric data of the Serra do Mar Sul Aero geophysical Project, performed during the 70's for CPRM. Later, terrestrial gamma-spectrometric surveys focused on the study of the differentiated Joaquim Murtinho Granite (JMG) in the NW corner of CGC, and the Serra do Carambei Granite, to the SW. In this paper, the results obtained for JMG are presented in two parts. The first deals with methodology and the presentation of several gamma-spectrometric 'color-scale' maps, indicating that results obtained in granites depend strongly on a climatic factor, given the mobility of K during weathering in subtropical climates with strong rainfalls, also favoring a greater mobility of U. Minerals that are U and Th hosts, documented in granites, are reviewed, together with the weathering processes that control the mobility of K, U and Th in soils. Strong K signals in granitic areas submitted to these climates document the presence of fresh rock and/or effects of hydrothermal alteration, while weak or nil signals are evidence of strong leaching of K during weathering. U and Th will be retained in the residual soils, in part leading to their selective enrichment, also coupled with soil migration to lower topographic levels by colluvial transport. The larger solubility of U (as uranyl ion) allows its liberation under oxidizing conditions, and its migration, limited by the possibility of absorption in newly formed mineral and organic soil phases. Th should be retained almost totally in resistant phases and, when liberated in solution, will mostly be fixed in organic and inorganic soil substances. (author)

Correlation of natural and artificial radionuclides in soils with pedological, climatological and geographic parameters

International Nuclear Information System (INIS)

Schuch, L.A.; Nordemann, D.J.R.; Zago, A.; Dallpai, D.L.; Godoy, J.M.; Pecequilo, B.

1994-01-01

Various types of soil samples were collected in the southern part of Brazil, with depth intervals of 5 cm, down to 50 cm, using a specially designed sampler. Pedological analysis of these soils were performed. Nuclear activities of 137 Cs (expressed in Bq m -2 ) and radioactive natural element ( 226 Ra, 228 Ra and 40 K) concentrations were determined by low background gamma-ray spectrometry. 137 Cs concentrations were correlated with radioactive natural element concentrations and pedological, climatological and geographic parameters to the soil samples collected. (author) 6 refs.; 4 tabs

Reference levels of natural radioactivity and (137)Cs in and around the surface soils of Kestanbol pluton in Ezine region of Çanakkale province, Turkey.

Science.gov (United States)

Öztürk, Buket Canbaz; Çam, N Füsun; Yaprak, Günseli

2013-01-01

The aim of the study was to conduct a systematic investigation on the natural gamma emitting radionuclides ((226)Ra, (232)Th and (40)K) as well as (137)Cs in the surface soils from Kestanbol/Ezine plutonic area in Çanakkale province as part of the environmental monitoring program on radiologic impact of the granitoid areas in Western Anatolia. The activity measurements of the gamma emitters in the surface soil samples collected from 52 sites distributed all over the region has been carried out, by means of HPGe gamma-ray spectrometry system. The activity concentrations of the relevant radionuclides in the soil samples appeared in the ranges as follows: (226)Ra was 20-521 Bq kg(-1); (232)Th, 11-499 Bq kg(-1)and; (40)K, 126-3181 Bq kg(-1), yet the (137)Cs was much lower than 20 Bq kg(-1)at most. Furthermore, based on the available data, the radiation hazard parameters associated with the surveyed soils were calculated. The present data also allowed evaluation of some correlations that may exist in the investigated natural radionuclides of the soil samples from the plutonic area in Çanakkale province. It is concluded from the above that the concerned region did not lead to any significant radiological exposure to the environment.

Quantifying Soil Erosion and Deposition Rates in Tea Plantation Area, Cameron Highlands, Malaysia Using 137Cs

International Nuclear Information System (INIS)

Zaini Hamzah; Che Yasmin Amirudin; Ahmad Saat; Ahmad Saat; Ab Khalik Wood

2014-01-01

The soil erosion and deposition in the hilly area is a great concern for the planters. In this study, the tea plantation was chosen to quantify the rates of soil erosion and deposition for it will provide information on the improvement of soil conditions and cost reduction of fertilizer consumption. The aims of this research are to determine the rate of soil erosion and deposition using environmental radionuclide, 137 Cs. Soil profile samples were collected by using scrapper plate and two cores soil sample were collected in the undisturbed forests area nearby. The 137 Cs activity concentration was measured using low background coaxial hyper pure germanium detector gamma spectrometer based on 137 Cs gamma energy peak at 661.66 keV. The highest erosion rate using Proportional Models and Mass Balance Model 1 was found in point HE top area which is 52.39 t ha -1 yr -1 and 95.53 t ha -1 yr -1 respectively while the lowest at location HF top which is 4.78 t ha -1 yr -1 and 4.97 t ha -1 yr -1 . The deposition rate was higher in HF center which is 216.82 t ha -1 yr -1 and 97.51 t ha -1 yr -1 and the lowest at HE center which is 0.05 t ha -1 yr -1 for both models used. (author)

Use of thermoluminescent dosimetry in gamma radiation fields studies

International Nuclear Information System (INIS)

Carron, W.

1987-01-01

The depth-dose curves for gamma rays in material of interest to agronomy were obtained using lithium fluoride thermoluminescent dosimeters. The dose conversion factors for LiF were determined from curves of the absorved dose versus depth in water, wood and soil. Mathematics equations were chosen to best fit these curves. In the view of the results we came to the conclusion that in the studied materials the absorved radiation dose presents a great variation to the depth and could be correlated through of the exponential regression. (author)

Preliminary measurements of gamma radiation in Chilean Antarctic Stations

International Nuclear Information System (INIS)

Stuardo B, E.

1983-01-01

Natural and artificial gamma radiation, 1 m above the soil, is being investigated in 4 Chilean Antartic Stations. The measurements are performed with different types of TLD detectors. Preliminary results in the Tte. Marsh Station are reported and discussed. An average exposition of 3,5 μR/h was found during a 108 days period. This exposition corresponds to an annual dose of about 40 mrad, 8% of the annual dose limit for individual of the public. The presence of low energy artificial radioisotopes was not found. (Author)

Surface gamma-ray survey of SX Tank Farm

International Nuclear Information System (INIS)

Stromswold, D.C.; Arthur, R.J.

1996-08-01

Measurements made over the surface of the SX Tank Farm at Hanford show Cs 137 to be the only significant gamma ray emitting contaminant. A high-purity germanium detector collected the data in the surface survey. Most of the detected radiation originated from specific above ground objects, such as pipes and vents. One area of increased radiation in the north section of the tank farm between tanks SX-102 and SX-105, was apparently due to contamination of the soil by Cs 137. An area of interest near tanks SX-108, SX-111, and SX-112, below which borehole logs has indicated deep Cs 137 contamination, also showed Cs 137 at the surface, but the signal originated mainly from surface objects rather than from contaminated soils. A significant result of the surface survey is the understanding that surface objects with contamination can affect the signal observed by borehole logging tools as they reach the ground surface

Vertical migration of 85Sr, 137Cs and 131I in various arable and undisturbed soils

International Nuclear Information System (INIS)

Palagyi, S.; Palagyiova, J.

2003-01-01

The vertical migration of 85 Sr, 137 Cs and 131 I in some arable and undisturbed single-contaminated soils was studied by gamma-spectrometry measurements under lysimetric laboratory conditions during irrigation of the soil profiles with wet atmospheric precipitation for about one year, except 131 I. A new simple exponential compartment (box) model was derived, which makes it possible to calculate the migration rate constants and migration rates in the individual soil layers (vertical sections) as well as the total vertical migration rate constants and total vertical migration rates of radionuclides in the bulk soil horizon. The relaxation times of radionuclides in respective soil horizons can also be evaluated. (author)

Two media method for linear attenuation coefficient determination of irregular soil samples

International Nuclear Information System (INIS)

Vici, Carlos Henrique Georges

2004-01-01

In several situations of nuclear applications, the knowledge of gamma-ray linear attenuation coefficient for irregular samples is necessary, such as in soil physics and geology. This work presents the validation of a methodology for the determination of the linear attenuation coefficient (μ) of irregular shape samples, in such a way that it is not necessary to know the thickness of the considered sample. With this methodology irregular soil samples (undeformed field samples) from Londrina region, north of Parana were studied. It was employed the two media method for the μ determination. It consists of the μ determination through the measurement of a gamma-ray beam attenuation by the sample sequentially immersed in two different media, with known and appropriately chosen attenuation coefficients. For comparison, the theoretical value of μ was calculated by the product of the mass attenuation coefficient, obtained by the WinXcom code, and the measured value of the density sample. This software employs the chemical composition of the samples and supplies a table of the mass attenuation coefficients versus the photon energy. To verify the validity of the two media method, compared with the simple gamma ray transmission method, regular pome stone samples were used. With these results for the attenuation coefficients and their respective deviations, it was possible to compare the two methods. In this way we concluded that the two media method is a good tool for the determination of the linear attenuation coefficient of irregular materials, particularly in the study of soils samples. (author)

Caesium Radionuclide Uptake from Wet Soil to Kangkung Plant (Ipomoea sp)

International Nuclear Information System (INIS)

Putu Sukmabuana; Poppy Intan Tjahaja

2009-01-01

Caesium radionuclide transfer from soil to kangkung plant (Ipomoea sp) generally consumed by people had been examined to obtain transfer factor value for internal radiation dose assessment via soil-plant-human pathway. The kangkung plants were cultivated on watered soil medium containing 134 Cs with concentration of about 80 Bq/g, and the 134 Cs uptake by plants, i.e root, stem, and leaves, were measured using gamma spectrometer. The 134 Cs plant uptake was expressed as transfer factor, i.e. ratio of plant 134 Cs concentration to 134 Cs concentration on soil medium. From this research it was obtained transfer factor value of 134 C from soil to plant is 0.07, and the transfer factor for root, stem, and leaves are 0.34 ; 0.05 ; 0,03 respectively, after 45 days cultivation. The transfer factor values are less than one, indicate that kangkung plant do not accumulate Cs radionuclide from soil. (author)

MAPRAD: mapping of radioactivity in Brazilian soils

International Nuclear Information System (INIS)

Ribeiro, Fernando C.A.; Signorelli, Carla de A.; Conti, Claudio de C.; Lauria, Dejanira da C.; Ferreira, Ingryd M.; Carvalho, Laercio L. de; Rio, Monica A. Pires do; Trindade Filho, Octavio Luiz; Gonzalez, Sergio de A.; Silva, Tadeu Augusto de A.; Sousa, Wanderson de O.; Cunha, Fernanda G. da

2011-01-01

The MAPRAD Project main objective is to increase the knowledge of the distribution of natural radioactivity in soils of Brazilian national territory and to provide (among others) information which are essential for medical geology and environmental radiation safety researches and for decision-making process regarding soil contamination levels. It also aims to make available the generated information for researchers and for public, through an online database. Soil samples are collected by the Geological Survey of Brazil (CPRM) and are sent to the Institute of Radioprotection and Dosimetry (IRD), National Commission of Nuclear Energy (CNEN), where they are processed and analyzed for determination of concentrations of radionuclides by gamma spectrometry. The results are inserted into a database containing the sample information as geographic coordinates of the samples and land use. After the sample analysis, results are made available for the scientific community access on Internet. (author)

Environmental radiation in coal and soil samples from Savannah area (Chatham County, GA)

International Nuclear Information System (INIS)

Hongo, D.; Ghuman, G.S.; Chandra, K.

1997-01-01

Radiation measurements were made in coal and fly ash samples from Savannah Electric ampersand Power Company (SEPCO) plant on the Savannah River and the soil core samples from three sites along the flow gradient of Savannah State University Campus Creek. The objective of this study was to determine the magnitude of natural radiation due to radon and potassium in the Savannah area and possible effect of external factors such as the operations at Savannah River Site (SRS). The instrument used for this purpose was Geiger Counter Model 500 (Tennelec/Nucleus, Inc.) which was standardized with known samples of Sr-90 (0.1 μCi t 1/2 = 28.6 yrs., beta radiation) and Co-60 (1.0 μCi t 1/2 = 5.27 yrs., gamma radiation). Beta and gamma radiations in the samples were differentiated with the help of polyethylene and lead absorbers. Results showed quite low radioactivity in bituminous coal from SEPCO plant and it reduced by a factor of 0.5 and 0.25 in fly ash and weathered fly ash, respectively. Radioactivity of soil samples was slightly greater in the top soil (0-3 cm) of two sites and it decreased markedly with depth (20 cm). Site III soil samples containing lime shells had a negligible radioactivity because carbonate rocks developed from calcareous skeletal matter have low radioactivity from their beginning. Radioactivity appeared to be mainly associated with the fine textured top soil of two sites (high clay content) and it exhibited very little leaching downward into lower layers. Clay particles with greater radioactivity, are formed from the decomposition of feldspars and micas which contain a large fraction of earth's potassium fraction. Measurements with the use of absorbers indicated that the observed radiation in all the samples was mainly due to the gamma rays. A comparison with the radioactivity in coal dust and fly ash samples from SRS revealed that the Savannah samples contained extremely low radiation, which may be due only to the natural sources

External exposure from gamma radiation in uranium mines

International Nuclear Information System (INIS)

Thomson, J.E.

1982-01-01

Radiation doses received by workers in a high ore grade uranium mine are compared to those of other radiation workers and the need to be able to calculate the exposure rate from an ore body is indicated. The uranium-238 decay chain is presented and particular reference is made to the main gamma emitters and secular equilibrium of the members of the chain. Difficulties in dealing with a self attenuating volume source, in which scattering is important, are pointed out and traditional methods of solution are mentioned. It is shown that in the special case of an infinite ore body a simple solution may be obtained using the energy conservation principle. A straightforward method for calculating the exposure rate from an arbitrarily shaped ore body is given and corrections due to air attenuation, different soil types and possible lack of secular equilibrium are dealt with. The gamma ray spectrum from the ore is discussed with specific reference to the selection of suitable exposure monitors and the calculation of transmission through shields

Procedures for sampling radium-contaminated soils

International Nuclear Information System (INIS)

Fleischhauer, H.L.

1985-10-01

Two procedures for sampling the surface layer (0 to 15 centimeters) of radium-contaminated soil are recommended for use in remedial action projects. Both procedures adhere to the philosophy that soil samples should have constant geometry and constant volume in order to ensure uniformity. In the first procedure, a ''cookie cutter'' fashioned from pipe or steel plate, is driven to the desired depth by means of a slide hammer, and the sample extracted as a core or plug. The second procedure requires use of a template to outline the sampling area, from which the sample is obtained using a trowel or spoon. Sampling to the desired depth must then be performed incrementally. Selection of one procedure over the other is governed primarily by soil conditions, the cookie cutter being effective in nongravelly soils, and the template procedure appropriate for use in both gravelly and nongravelly soils. In any event, a minimum sample volume of 1000 cubic centimeters is recommended. The step-by-step procedures are accompanied by a description of the minimum requirements for sample documentation. Transport of the soil samples from the field is then addressed in a discussion of the federal regulations for shipping radioactive materials. Interpretation of those regulations, particularly in light of their application to remedial action soil-sampling programs, is provided in the form of guidance and suggested procedures. Due to the complex nature of the regulations, however, there is no guarantee that our interpretations of them are complete or entirely accurate. Preparation of soil samples for radium-226 analysis by means of gamma-ray spectroscopy is described

Soil structure changes evaluated with computed tomography;Mudancas na estrutura do solo avaliada com uso de tomografia computadorizada

Energy Technology Data Exchange (ETDEWEB)

Pires, Luiz Fernando [Universidade Estadual de Ponta Grossa (UEPG), PR (Brazil). Dept. de Fisica; Bacchi, Osny Oliveira Santos, E-mail: osny@cena.usp.b [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

2010-04-15

The objective of this work was to evaluate in millimetric scale changes in soil bulk density and porosity, using the gamma-ray computed tomography in soil samples with disturbed structure due to wetting and drying (W-D) cycles. Soil samples with 98.1 cm{sup 3} were sieved using a 2 mm mesh and homogeneously packed in PVC cylinders. Soil samples were submitted to 1, 2, and 3 W-D cycles. Control samples were not submitted to W-D cycles. After repetitions of W-D cycles, soil sample porosity decreased and soil layers became denser. Computed tomography allowed a continuous analysis of soil bulk density and also soil porosity along millimetric (0.08 cm) layers, what cannot be provided by traditional methods used in soil physics. (author)

PIXE analysis of sand and soil from Ulaanbaatar and Karakurum, Mongolia

Science.gov (United States)

Markwitz, A.; Barry, B.; Shagjjamba, D.

2008-09-01

Twenty-one sand and soil samples were collected at the surface from 22 to 25 June 2007 at sampling sites from Ulaanbaatar to Karakurum, Mongolia. The sand samples were collected from constantly changing sand dunes which may still contain salt from prehistoric oceans. The dry sand and soil samples were processed for PIXE and PIGE analyses. A clear division between soils and sand become apparent in the silicon results. Concentrations of all bulk elements in human habitation samples and of Si, Al, K and Fe in dry lake/flood plain samples are similar to those in the soils and sands. Among elements which could be regarded as being at trace concentrations the average S concentration in the soils is 0.9 g kg-1 whereas it is not detected in the sand samples. Zinc and Cu concentrations are both higher in the soils than the sands and are strongly correlated. A surprising presence of uranium at a concentration of 350 mg kg-1 was detected in the PIXE measurement on one of the dry lake samples. Gamma spectrometry confirmed the presence of U in this sample and also at a lower level in a sample from the lake shore, but in none of the other samples. Further, the gamma spectrometry showed that 238U decay products were present only at a level corresponding to about 3 mg kg-1 U for a system in radioactive equilibrium, a figure which is typical for U in the earth's crust. Disequilibria between 238U and its decay products occur naturally but such a high degree of separation at high concentration would be unique if confirmed. PIXE and PIGE measurements of these samples highlight the difficulty in correlating trace element measurements with occurrence of indicators of sea salt in air particulate samples.

Assessment of background gamma radiation levels around Tummalapalle uranium mining and processing facility, Andhra Pradesh

International Nuclear Information System (INIS)

Rana, B.K.; Dhumale, M.R.; Molla, Samim; Rao, K.B.; Jha, S.K.; Tripathi, R.M.; Sahu, S.K.

2018-01-01

Natural environmental radioactivity and the associated external exposure due to gamma radiation depend primarily on the geological and geographical conditions, and appear at different levels in the soil of each region in the world. The dose received by the population in a region comprises of (i) external gamma radiation dose due to cosmic rays and primordial radionuclides; (ii) inhalation dose due to radon, thoron and their progeny, and (iii) ingestion dose due to the intake of radionuclides through the consumption of food, milk, water, etc. In this study, background gamma radiation level around Tummalapalle uranium mining and processing site was estimated by using radiation survey meter and deploying environmental TLDs. The generated data can be served as baseline for this area for future comparison for prolonged operation of the plant, for the upcoming adjacent projects and during decommissioning phase of the mine, mill and tailings pond

An injected gamma-tracer method for soil-moisture movement investigations in arid zones

International Nuclear Information System (INIS)

Nair, A.R.; Navada, S.V.; Rao, S.M.

1980-01-01

A method for the in-situ determination of soil-moisture transport rates using K 3 60 Co(CN) 6 is discussed. The tracer compares well with tritiated water in laboratory investigations and the results obtained in limited field studies are very encouraging. The method promises to be of specific interest in arid-zone investigations where the soil-moisture fluxes in liquid and vapour phases could cause complications for tritium tracer data interpretation. (author)

Retention of low-level radioacrive waste material by soil

International Nuclear Information System (INIS)

Essington, E.H.; Fowler, E.B.; Polzer, W.L.

1979-01-01

Beacuse of the wide variations in soil and waste characteristics, the degree of radionuclide retention would be expected to vary; knowledge of that variation may be of value in predicting radionuclde mobility. This report discusses results of investigations of radioactive waste/soil interactions as they relate to radionucldie retention and its variability among soils and radionuclides. In soil column leaching studies, radioactive waste solutions were applied to four different soil types; 241 Am, 88 Y, and 172 Hf were retained in the top four cm of soil with better than 90% retained by a protective surface sand layer. Less than 50% of the 85 Sr, 137 Cs, and 83 Rb was retained by the surface sand. No 88 Y, 172 Hf, 85 Sr, 137 Cs, or 83 Rb was detected by gamma counting in the leachate solutions, however, using a more sensitive analytical technique small amounts of 238 Pu, 239 240 Pu and 241 Am were found in leachates from all soils. It appears that release of this small fraction of mobile radionuclide may have a significant long-term impact on the environment. It aslo appears that reliance for attenuation of some radionuclides can not be placed solely on characteristics of the soil matrix

Environmental gamma and radon dosimetry in Venezuela

CERN Document Server

Sajo-Bohus, L; Urbani, F; Castro, D D; Greaves, E D; Liendo, J A

1999-01-01

Environmental gamma exposure and radon concentration levels measured in Venezuelan regions are presented. A new generation image analyser was used for alpha particle track counting in CR-39 detectors. Mineral water wells from where water is supplied for massive consumption have an alpha activity around 0.450 Bq L sup - sup 1 and few of them have concentrations above 50 Bq L sup - sup 1. Coastal potable water activity is on the average around 5.3 +- 12% Bq L sup - sup 1. Indoor radon national average is 36 +- 5% Bq m sup - sup 3; in two of the 36 monitored sites, the measured average is above 400 +- 5% Bq m sup - sup 3. In air gamma dose values are between 100 and 144 nGy h sup - sup 1. In soil, sup 1 sup 3 sup 7 Cs concentration is around 0.5 and 10 Bq kg sup - sup 1 at the depth of down to 20 cm. Building materials were included in this study. sup 7 Be and sup 1 sup 3 sup 7 Cs were measured in low concentration in tropical plants on Tepuy-s (sacred mountains in the Amazonas State). Geological active faults w...

Aircraft-borne spectrometry - a fast method for nuclide-specific measurement of soil contamination

International Nuclear Information System (INIS)

Winkelmann, I.; Schweiger, M.; Thomas, M.; Endrulat, H.J.

1991-01-01

An airworthy gamma spectrometer system for fast and large-area, nuclide-specific measurement of the soil contamination is described. The system encompasses an ultrapure germanium detector combined with a computer-controlled multichannel analyser system. The development from the laboratory system to an industrial-scale measuring system is explained. The practical testing is explained and first results are reported, obtained from measuring flights for the nuclide-specific determination of the soil contamination in the free State of Bavaria. (orig.) [de

Technology information profile: RL321103 -- In situ gamma spectrometer

International Nuclear Information System (INIS)

Schilk, A.J.

1993-11-01

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

Correlation of gamma spectrometer measurements at surface with concentrations and distributions of subsurface radium contamination: Development, verification and application of methodology

International Nuclear Information System (INIS)

McCallum, B.A.; Clement, C.H.; Huffman, D.; Stager, R.H.

2000-01-01

This work is a step forward in the investigation of data gathering principles and analysis tools for improved estimates of subsurface radium contamination concentrations and distributions using surface gamma radiation spectra. Techniques to solve the inverse problem of estimating surface gamma radiation spectra given a fully known subsurface radium distribution have been investigated and applied with success. These techniques fell into three broad categories: empirical (using laboratory and field data), analytical (using mathematical derivations of relationships), and computer simulation (using Monte-Carlo photon transport simulation methods). Methods of analyzing surface spectra to estimate certain source parameters have been studied. The most fully developed methods are those involving the ratio of the areas of two peaks of differing energy from the same radionuclide to determine the source depth. For a point source of radium and its progeny, these techniques are able to reliably estimate the source depth from a single gamma radiation spectrum taken at the surface directly above the source. The only significant uncertainties in this case are the soil density and uncertainties introduced as a result of counting statistics. Further work remains to fully achieve the goals of the larger project: to develop a comprehensive suite of tools for the improved interpretation of surface gamma radiation spectra from subsurface distributions of radium contaminated soil. (author)