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In this work, the probable sites of the radioactive mineralization in the younger granite of the Um Bogma area was mapped, prospected and detected by using geospatial technology. Our approach combined diverse data that have a close relationship with radioactive mineralization. These data are lithological, hydrothermal alteration minerals and airborne data. To achieve the aim of this work, the geospatial technology was used. Two techniques band ratio and Feature Oriented Principal Component Analysis (Crosta technique) were applied on ASTER satellite images to distinguish lithology and minerals indicative of hydrothermal alteration. Estimated weights were assigned to the lithology, alteration minerals and airborne data based on statistical methods. All these weighted data integrated to produce the predictive control models that related to mineralization using GIS applications. Three potential sites for radioactive mineralization were identified from the predictive control model. These potential sites were validated via fieldwork surveillance from these sites. Both of fieldwork and laboratory examinations confirm the association of these potential sites with the altered younger granite where uranophane and other minerals are recorded. [ABSTRACT FROM AUTHOR]

Multispectral imaging is of wide application for its capability in acquiring the spectral information of scenes. Due to hardware limitation, multispectral imaging device usually cannot achieve high-spatial resolution. To address the issue, this paper proposes a multispectral image super-resolution algorithm, referred as SRIF, by fusing the low-resolution multispectral image and the high-resolution (HR) RGB image. It deals with the general circumstance that image intensity is linear to scene radiance for multispectral imaging devices while is nonlinear and unknown for most RGB cameras. The SRIF algorithm first solves the inverse camera response function and a spectral sensitivity function of RGB camera, and establishes the linear relationship between multispectral and RGB images. Then the unknown HR multispectral image is efficiently reconstructed according to the linear image degradation models. Meanwhile, the edge structure of the reconstructed HR multispectral image is kept in accordance with that of the RGB image using a weighted total variation regularizer. The effectiveness of the SRIF algorithm is evaluated on both public datasets and our image set. Experimental results validate that the SRIF algorithm outperforms the state-of-the-arts in terms of both reconstruction accuracy and computational efficiency. [ABSTRACT FROM AUTHOR]

The intermittent flow (slug and plug type) of liquid-gas mixtures in a horizontal pipeline measured by the specific radiometric apparatus is presented. The measurement system consists of two sources of Am-241 gamma radiation and two scintillation probes. An analysis of the signals measured by the radiometric equipment is performed in the domain of time and of frequency. Recognised signal parameters are directly referred to physical quantities associated with a liquid-gas flow. The employed methodology enables determination of gas-phase flow velocity and estimation of the average depth and length of bubble gas structures. In the paper, the processing and interpretation results of the selected experiment are presented to show the in-depth description of gas structures and the type of flows recognition. [ABSTRACT FROM AUTHOR]

This paper discusses the intersatellite radiometric calibration for microwave sounders in support of NASA’s Global Precipitation Measurement (GPM) mission. This paper is an extension of previous GPM Intersatellite Calibration Working Group work, which assesses the robustness of the Central Florida Remote Sensing Laboratory “double difference” technique for sounders intercalibration. In this paper, we will analyze the intercalibration between the Advanced Technology Microwave Sounder on board the National Polar-orbiting Operational Environmental Satellite System Preparatory Project, the Microwave Humidity Sounder on board the MetOp-A and MetOp-B and NOAA-18 and NOAA-19, and the Sondeur Atmosphérique du Profil d’Humidité Intertropicale par Radiométrie sounder onboard the Megha-Tropiques satellite. The sensitivity of the calibration to the geophysical parameters and incidence angles is investigated using two years data. Here, it is observed that a reliable intercalibration can be made only when the path lengths of the two sensors are similar, so when matching the scan angles for the two sensors, the sensitivity of the biases upon the water vapor profiles is significantly reduced. [ABSTRACT FROM AUTHOR]

Ambient gamma dose, radon, and rainfall have been monitored in southern Bucharest, Romania, from 2010 to 2016. The seasonal cycle of background ambient gamma dose peaked between July and October (100–105 nSv h −1 ), with minimum values in February (75–80 nSv h −1 ), the time of maximum snow cover. Based on 10 m a.g.l. radon concentrations, the ambient gamma dose increased by around 1 nSv h −1 for every 5 Bq m −3 increase in radon. Radon variability attributable to diurnal changes in atmospheric mixing contributed less than 15 nSv h −1 to the overall variability in ambient gamma dose, a factor of 4 more than synoptic timescale changes in air mass fetch. By contrast, precipitation-related enhancements of the ambient gamma dose were 15–80 nSv h −1 . To facilitate routine analysis, and account in part for occasional equipment failure, an automated method for identifying precipitation spikes in the ambient gamma dose was developed. Lastly, a simple model for predicting rainfall-related enhancement of the ambient gamma dose is tested against rainfall observations from events of contrasting duration and intensity. Results are also compared with those from previously published models of simple and complex formulation. Generally, the model performed very well. When simulations underestimated observations the absolute difference was typically less than the natural variability in ambient gamma dose arising from atmospheric mixing influences. Consequently, combined use of the automated event detection method and the simple model of this study could enable the ambient gamma dose “attention limit” (which indicates a potential radiological emergency) to be reduced from 200 to 400% above background to 25–50%. [ABSTRACT FROM AUTHOR]

This paper adopts a formal model-testing approach to the Peruvian radiocarbon ( 14 C) record, the site of the first aggregate analysis of this type of archaeological data. Using a large and improved regional dataset of radiometric determinations (n = 1180) from the period 14000–3000 14 C years before present, the study performs a comparative analysis of the demographic trajectories of two sub-regions, the desert coast and Andean highlands. Against the backdrop of theoretical models of population growth, and controlling for taphonomic factors and sampling biases, the study performs global significance and permutation tests on the data. These provide a necessary measure of statistical confidence that have hereto been absent from the discussion of pre-Columbian demography. Contrary to the findings of prior work, this study of radiocarbon data in Peru reveals that regional trends in the data are statistically indistinguishable. Further testing and comparison to climate archives is able to illustrate sustained population growth over the entire Holocene epoch in this region, with only a few notable exceptions at the end of the mid-Holocene (5000 cal BP). The findings of the analysis are viewed in relation to the cultural and technological changes that indigenous societies experienced in the timeframe in question, and some directions for methodological advances are suggested. [ABSTRACT FROM AUTHOR]

The present study addresses the calibration of four types of partial discharge (PD) emulators used in the development of a PD Wireless Sensor Network (WSN). Three PD emulators have been constructed: a floating-electrode emulator, and two internal PD emulators. Both DC and AC high-voltage power supplies are used to initiate PD, which is measured using concurrent free-space radiometry (FSR) and a galvanic contact method based on the IEC 60270 standard. The emulators have been measured and simulated, and a good agreement has been found for the radiated fields. A new method of estimating the absolute PD activity level from radiometric measurements is proposed. [ABSTRACT FROM PUBLISHER]

Flight height is a fundamental parameter for correcting the gamma signal produced by terrestrial radionuclides measured during airborne surveys. The frontiers of radiometric measurements with UAV require light and accurate altimeters flying at some 10 m from the ground. We equipped an aircraft with seven altimetric sensors (three low-cost GNSS receivers, one inertial measurement unit, one radar altimeter and two barometers) and analyzed ~3 h of data collected over the sea in the (35-2194) m altitude range. At low altitudes (H < 70 m) radar and barometric altimeters provide the best performances, while GNSS data are used only for barometer calibration as they are affected by a large noise due to the multipath from the sea. The ~1 m median standard deviation at 50 m altitude affects the estimation of the ground radioisotope abundances with an uncertainty less than 1.3%. The GNSS double-difference post-processing enhanced significantly the data quality for H > 80 m in terms of both altitude median standard deviation and agreement between the reconstructed and measured GPS antennas distances. Flying at 100 m the estimated uncertainty on the ground total activity due to the uncertainty on the flight height is of the order of 2%. [ABSTRACT FROM AUTHOR]

Proximal sensing as the near field counterpart of remote sensing offers a broad variety of applications. Imaging spectroscopy in general and translational laboratory imaging spectroscopy in particular can be utilized for a variety of different research topics. Geoscientific applications require a precise pre-processing of hyperspectral data cubes to retrieve at-surface reflectance in order to conduct spectral feature-based comparison of unknown sample spectra to known library spectra. A new pre-processing chain called GeoMAP-Trans for at-surface reflectance retrieval is proposed here as an analogue to other algorithms published by the team of authors. It consists of a radiometric, a geometric and a spectral module. Each module consists of several processing steps that are described in detail. The processing chain was adapted to the broadly used HySPEX VNIR/SWIR imaging spectrometer system and tested using geological mineral samples. The performance was subjectively and objectively evaluated using standard artificial image quality metrics and comparative measurements of mineral and Lambertian diffuser standards with standard field and laboratory spectrometers. The proposed algorithm provides highly qualitative results, offers broad applicability through its generic design and might be the first one of its kind to be published. A high radiometric accuracy is achieved by the incorporation of the Reduction of Miscalibration Effects (ROME) framework. The geometric accuracy is higher than 1 μpixel. The critical spectral accuracy was relatively estimated by comparing spectra of standard field spectrometers to those from HySPEX for a Lambertian diffuser. The achieved spectral accuracy is better than 0.02% for the full spectrum and better than 98% for the absorption features. It was empirically shown that point and imaging spectrometers provide different results for non-Lambertian samples due to their different sensing principles, adjacency scattering impacts on the signal and anisotropic surface reflection properties. [ABSTRACT FROM AUTHOR]

Radiometric cross-calibration between the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and the Terra-Moderate Resolution Imaging Spectroradiometer (MODIS) has been partially used to derive the ASTER radiometric calibration coefficient (RCC) curve as a function of date on visible to near-infrared bands. However, cross-calibration is not sufficiently accurate, since the effects of the differences in the sensor's spectral and spatial responses are not fully mitigated. The present study attempts to evaluate radiometric consistency across two sensors using an improved cross-calibration algorithm to address the spectral and spatial effects and derive cross-calibration-based RCCs, which increases the ASTER calibration accuracy. Overall, radiances measured with ASTER bands 1 and 2 are on averages 3.9% and 3.6% greater than the ones measured on the same scene with their MODIS counterparts and ASTER band 3N (nadir) is 0.6% smaller than its MODIS counterpart in current radiance/reflectance products. The percentage root mean squared errors (%RMSEs) between the radiances of two sensors are 3.7, 4.2, and 2.3 for ASTER band 1, 2, and 3N, respectively, which are slightly greater or smaller than the required ASTER radiometric calibration accuracy (4%). The uncertainty of the cross-calibration is analyzed by elaborating the error budget table to evaluate the International System of Units (SI)-traceability of the results. The use of the derived RCCs will allow further reduction of errors in ASTER radiometric calibration and subsequently improve interoperability across sensors for synergistic applications. [ABSTRACT FROM AUTHOR]

Proximal imaging remote sensing technologies are used to phenotype and to characterize organisms based on specific external body reflectance features. These imaging technologies are gaining interest and becoming more widely used and applied in ecological, systematic, evolutionary, and physiological studies of plants and also of animals. However, important factors may impact the quality and consistency of body reflectance features and therefore the ability to use these technologies as part of non-invasive phenotyping and characterization of organisms. We acquired hyperspectral body reflectance profiles from three insect species, and we examined how preparation procedures and preservation time affected the ability to detect reflectance responses to gender, origin, and age. Different portions of the radiometric spectrum varied markedly in their sensitivity to preparation procedures and preservation time. Based on studies of three insect species, we successfully identified specific radiometric regions, in which phenotypic traits become significantly more pronounced based on either: 1) gentle cleaning of museum specimens with distilled water, or 2) killing and preserving insect specimens in 70% ethanol. Standardization of killing and preservation procedures will greatly increase the ability to use proximal imaging remote sensing technologies as part of phenotyping and also when used in ecological and evolutionary studies of invertebrates. [ABSTRACT FROM AUTHOR]

Ground investigations of the activity concentrations from primordial radionuclides ( 238 U, 232 Th and 40 K) were conducted in Akpabuyo, southeastern Nigeria. These investigations were aimed at assessing the magnitude and spatial distribution of activity concentrations from primordial radionuclides. Also, radiological hazard assessment and their associated risk to both human environmental healths and suitability of soils in the area for constructing dwellings places will be made. Instrument used for the investigations, which were conducted both randomly and along 6 profiles with inter-profile distance of 100 m, was a potable GRS-2 model of a Pico Envirotec spectrometer. Activity concentrations in the area, which vary with spatial distribution of soil texture, lithology, land use and topography, range between 2.22 and 116.09 Bq kg −1 (mean of 34.67 Bq kg −1 ) for 238 U, 3.65–87.41 Bq kg −1 (mean of 38.59 Bq kg −1 ) for 232 Th and 6.26–384.99 Bq kg −1 (mean of 114.66 Bq kg −1 ) for 40 K. The mean activity concentrations of 238 U and 232 Th are marginally higher than world averages of 30 and 39 Bq kg −1 respectively. However, the activity concentration of 40 K, which is the most abundant radionuclide (60.02%), is less than the world average of 400 Bq kg −1 . Results obtained from skew and kurtosis analyses of the activity concentration data show that the distribution of 238 U and 232 Th radionuclides in the soils is nearly symmetrical. The radiological hazard indicators computed from the activity concentrations of the radionuclides are all below maximum permissible limits. For instance, values of radium equivalent, which vary from 41.72 to 171.02 Bq kg −1 (average of 98.68 Bq kg −1 ), are below the permissible limit of 370 Bq kg −1 . External and internal hazard indices vary between 0.11 and 0.46 Bq kg −1 (mean of 0.27 Bq kg −1 ) and 0.14–0.72 Bq kg −1 (mean of 0.36 Bq kg −1 ) respectively. These results are below the 1 Bq kg −1 benchmark required for materials to be safe for use in constructing residential buildings. Absorbed dose, indoor and outdoor annual effective dose rates vary from 19.37 to 76.72 nGy h −1 (mean of 44.11 nGy h −1 ), 0.10–0.38 mSv yr −1 (mean of 0.22 mSv yr −1 ) and 0.02–0.09 (mean of 0.05 mSv yr −1 ) respectively. The mean absorbed dose rate is almost equal to the world average of 44 nGy hr −1 , but the means of the indoor and outdoor annual effective doses are below the 0.50 mSv yr −1 limit set for materials to be safe. Thus, the soils in Akpabuyo are safe for use in constructing dwelling places for the population. However, periodical monitoring of the radionuclides and radioisotopes should be performed. [ABSTRACT FROM AUTHOR]

The brightness non-uniformity caused by vignetting effects, viewing, and illumination angels in remote sensing images reduces the interpretation precision. A multi-resolution variational Retinex scheme is proposed in this paper to efficiently correct the non-uniform brightness in airborne remote sensing images. This variational Retinex model is non-linear, constrained by the grey-world assumption and the total variation regularization. A Gaussian image pyramid is used to construct the multi-resolution scheme. The multi-resolution scheme reduces the calculation burden and raises the calculation efficiency. The fast split Bregman (SB) iteration method is employed to optimize the proposed non-linear model in each level of the multi-resolution scheme. This decomposes the complicated model into several simple sub-problems and greatly improves the calculation efficiency. The multi-resolution scheme embedded with the SB iteration method was applied to both synthetic and real remote sensing images. The experimental results show that the brightness non-uniformity can be corrected, and the spectral information can be effectively restored. Moreover, the calculation efficiency is raised by about 60–110 times, compared to the traditional single-resolution solving method. [ABSTRACT FROM AUTHOR]

Based on new scientific information and broad public consultation, the Government of Canada updated the guideline for exposure to indoor radon and launched a multi-year radon programme in 2007. Major achievements in radon research accomplished in the past 7 y are highlighted here. [ABSTRACT FROM AUTHOR]

Application capabilities of optical microscopes and microspectroscopes can be considerably enhanced by a proper calibration of their spectral sensitivity. We propose and demonstrate a method of relative and absolute calibration of a microspectroscope over an extraordinary broad spectral range covered by two (parallel) detection branches in visible and near-infrared spectral regions. The key point of the absolute calibration of a relative spectral sensitivity is application of the standard sample formed by a thin layer of Si nanocrystals with stable and efficient photoluminescence. The spectral P L quantum yield and the P L spatial distribution of the standard sample must be characterized by separate experiments. The absolutely calibrated microspectroscope enables to characterize spectral photon emittance of a studied object or even its luminescence quantum yield (QY) if additional knowledge about spatial distribution of emission and about excitance is available. Capabilities of the calibrated microspectroscope are demonstrated by measuring external Q Y of electroluminescence from a standard poly-Si solar-cell and of photoluminescence of Erdoped Si nanocrystals. [ABSTRACT FROM AUTHOR]

Despite eminent development of digital range imaging techniques, difficulties persist in the virtualization of objects with poor radiometric information, in other words, objects consisting of homogeneous colours (totally white, black, etc.), repetitive patterns, translucence, or materials with specular reflection. This is the case for much of the Jorge Oteiza's works, particularly in the sculpture collection of the Museo Fundación Jorge Oteiza (Navarra, Spain). The present study intend to analyse and asses the performance of two digital 3D-modeling methods based on imaging techniques, facing cultural heritage in singular cases, determined by radiometric characteristics as mentioned: Shape from Silhouette and Shape from Stereo. On the other hand, the text proposes the definition of a documentation workflow and presents the results of its application in the collection of sculptures created by Oteiza. [ABSTRACT FROM AUTHOR]

The Visible and Infrared Imaging Radiometer Suite (VIIRS) on board the Suomi National Polar-Orbiting Partnership satellite brings new opportunities for improving scientists' understanding of deep convective cloud (DCC) radiometry with multiple bands in the visible (VIS), near-infrared (NIR), and longwave infrared (LWIR) spectrum. This paper investigated the radiometric sensitivity of DCC reflectance to spatial resolution, brightness temperature of the LWIR band centered at ~11 μm (TB11), TB11 calibration bias, and cluster size using VIIRS VIS (M5), NIR (M7 and I2), and LWIR (M15 and I5) observations at 375- and 750-m spatial resolutions. The mean and mode of the monthly probability distribution functions of DCC reflectance are used as two important indices in using DCC for calibration, and the results show that the onboard radiometric calibration of M5, M7, and I2 are stable during May 2013-April 2014 despite severe instrument responsivity degradations. The standard deviations of the mean and mode of monthly DCC reflectance are 0.5% and 0.2%, respectively, for all bands. It was found that a TB11 calibration bias on the order of 0.5 K has minimal impact on monthly DCC reflectance, especially when the mode method is used. The mean and mode of VIS and NIR DCC reflectance are functions of spatial resolution, TB11 threshold, and DCC cluster size in all seasons. However, the mode of DCC reflectance is more stable than the mean in terms of all three factors. Therefore, the mode is more suitable as an indicator of calibration stability for individual VIS and NIR bands. [ABSTRACT FROM AUTHOR]

The Landsat-7 ETM+ sensor has been operating on orbit for more than 12 years, and characterizations of its performance have been ongoing over this period. In general, the radiometric performance of the instrument has been remarkably stable: 1) noise performance has degraded by 2% or less overall, with a few detectors displaying step changes in noise of 2% or less; 2) coherent noise frequencies and magnitudes have generally been stable, though the within-scan amplitude variation of the 20 kHz noise in bands 1 and 8 disappeared with the failure of the scan line corrector and a new similar frequency noise (now about 18 kHz) has appeared in two detectors in band 5 and increased in magnitude with time; 3) bias stability has been better than 0.25 DN out of a normal value of 15 DN in high gain; 4) relative gains, the differences in response between the detectors in the band, have generally changed by 0.1% or less over the mission, with the exception of a few detectors with a step response change of 1% or less; and 5) gain stability averaged across all detectors in a band, which is related to the stability of the absolute calibration, has been more stable than the techniques used to measure it. Due to the inability to confirm changes in the gain (beyond a few detectors that have been corrected back to the band average), ETM+ reflective band data continues to be calibrated with the prelaunch measured gains. In the worst case, some bands may have changed as much as 2% in uncompensated absolute calibration over the 12 years. [ABSTRACT FROM AUTHOR]

A significant development of the principal component analysis technique, to non-intrusively infer the depth of the fission fragment cesium-137, when it is buried under silica sand has been described. In this paper we describe the advancement of the technique by further validating it using blind tests for applications outside of the laboratory, where not only the depth (z) but also the surface (x, y) location of \gamma-ray emitting contamination is often poorly characterized. Also uncertainty analysis has been conducted to test the robustness of the technique. At present the technique has been tested at the point of maximum activity above the entrained \gamma-ray emitting source (where the optimal x, y location is known). This is not usually practical in poorly characterized environments where the detector cannot be conveniently placed at such an optimal location to begin with and scanning at multiple points around the region of interest is often required. Using a uniform scanning time, the point of maximum intensity can be located by sampling in terms of total count rate, and converging on this optimal point of maximum intensity. [ABSTRACT FROM AUTHOR]

The article offers information on the concept, designing and biological application of chemical probes for bio-imaging purposes. It mentions that chemical probes are of several types including fluorescence resonance energy transfer (FRET) probes, zinc probes and magnetic resonance imaging probes. It also states the advantage of FRET probes which include radiometric measurement in living cells and also reduces the artefacts from microscopic imaging systems.

Abstract: A scored lithological map including 11 radiometric units is established through applying a factor analysis approach to aerial spectrometric data of Area-3, Northern Palmyrides, Syria. Regional uranium migration trends have also been estimated by using the airborne spectrometric data of Area-3, where different regional maps explaining the migration trends have been established. It was found that the four lithological phosphatic units P1, P2, P3 and P4 are the main uranium sources in the study region, where the uranium migration is in an outward direction. The other seven lithological units C1, C2, C3, M1, M2, M3 and M4 are successively and differentially enriched by uranium during the geological evolution of the crust, where uranium migration is generaly in an inward direction. The combination of the obtained uranium migration results with the dominant geological and tectonic conditions allows the proposition of a plausible scenario of six steps, which explain the different geological processes taking place in the study area. Favorable transverse structures for uranium occurences have been localized and qualified as being the most important for prospecting. More detailed exploration activities are needed in the study area to evaluate the potential of such structures as a function of depth. The proposed model could be applicable to similar phosphatic environments. [Copyright &y& Elsevier]

Abstract: Qualitative and quantitative statistical analysis have been applied to the Airborne spectrometric data from the Al-Awabed region and its surroundings (Area-3), Northern Palmyrides, Syria. It was shown that equivalent uranium eU values vary between a minimum of 0.01 and a maximum of 22.33ppm. The probability graph has been used to compute the threshold level of uranium in the study area. It was found that this threshold level of 5.54ppm agrees well with that obtained by traditional statistical computation . Uranium prospecting methodology is proposed in order to explain the origin of the radioactive anomalies related to the Al-Awabed region and its surroundings in Area-3, and to determine the dominant geological conditions that effectively contribute to the radioactive anomalies occurring in the study area. Four radioactive-geological profiles have been established in Area-3, where their analysis and study reveal that lowlands and basins, the unconformity between Paleogene and Neogene, the contact between Cretaceous and Paleogene and the phosphate beds themselves are considered favorable environments for uranium deposits. The proposed methodology is proven and field verified and can be therefore applied in other areas considered as promising for uranium deposits. [Copyright &y& Elsevier]

The article compared the Human Monitoring Laboratory (HML) and the Normalized Man (NORMAN) voxel phantom with the VIP-Man voxel phantom measured in a scanning detector whole body counter. Results reveal that NORMAN gives a counting efficiency that is 21 percent to 46 percent higher than VIP-Man over the energy range of 122 keV to 1,836 keV. According to the article, voxel phantoms has lower counting efficiencies, perhaps due to the more complex internal structure of the voxel phantoms that offers more signal attenuation or simply due to counting geometry effects.

Measurements of 226Ra, 232Th and 40K activity concentrations in commercial granite tiles imported in Greece were performed using gamma-ray spectrometry. The activity concentration of 226Ra, 232Th and 40K ranged from 1 to 434, 2 to 239 and 71 to 1576 Bq kg-1, respectively. The calculated activity concentration index (I) values for all granite samples examined were found to be within the EC limit values for superficial and other materials with restricted use. [ABSTRACT FROM AUTHOR]

Neutron activation analysis of plant samples for trace amounts of nickel has applications in various fields. Landsberger and Robinson (Trans Am Nucl Soc 102:187-188, ) found their measurement of the concentrations of nickel for different NIST reference materials to be significantly greater than the certified values when measuring nickel from the 810.8 keV gamma ray that comes from Co from the Ni(n,p) reaction. They determined that this overestimation was due to a significant interference by the presence of Eu at 810.5 keV, and presented a method for correcting this interference. Their method involved a long thermal irradiation and correction of gamma ray counts based on the 1,408 keV belonging to Eu. This paper presents an alternative approach, which involves irradiating the samples with epithermal neutrons, which suppressed the Eu to the point of being negligible for samples with low levels of europium. Both methods were determined to work well for the identification of nickel concentrations by neutron activation analysis. [ABSTRACT FROM AUTHOR]

A mineralization conceptual model for uranium of the metamorphic massif of Isla de la Juventud was established taking into account the study of the geological and metallogenic characteristic of the territory. The determined indications of mineralization were plotted on the geological map in order to conform a forecasting map and the selection of 22 hypothetical promising areas was carried out. As result of the field words three really promising areas were selected. A group of exploration techniques needed to evaluate the targets areas is presented. [ABSTRACT FROM AUTHOR]

This article reports that the United Nations International Atomic Energy Agency (IAEA)'s inspectors have started using direct satellite feeds from nuclear facilities to track sensitive nuclear materials and check they are not being diverted for non-peaceful use. The first field trial connecting a nuclear power plant in Slovakia to IAEA headquarters, reportedly, started in April 2005. Images and electronic seal data recorded at a Slovak nuclear spent fuel pool and reactor core are now downloaded daily to the IAEA's safeguards computer systems. The images are taken every five minutes, the data is encrypted/authenticated, and then transmitted to Vienna, Austria. The IAEA is now working with the European Space Agency to assess the feasibility and cost of using satellites to relay data from 100 plus surveillance systems the Agency operates in 13 countries. The IAEA first started using remote monitoring of selected nuclear facilities on a trial basis in the 1990's, using telephone lines and the Internet to transmit the data.