A considerable fraction of radioactivity entering the environment from different nuclear events is associated with particles. The impact of these events can only be fully assessed where there is some knowledge about the mobility of particle bound radionuclides entering the environment. The behavior of particulate radionuclides is dependent on several factors, including the physical, chemical and redox state of the environment, the characteristics of the particles (e.g., the chemical composition, crystallinity and particle size) and on the oxidative state of radionuclides contained in the particles. Six plutonium-containing particles stemming from Runit Island soil (Marshall Islands) were characterized using non-destructive analytical and microanalytical methods. By determining the activity of {sup 239,240}Pu and 241Am isotopes from their gamma peaks structural information related to Pu matrix was obtained, and the source term was revealed. Composition and elemental distribution in the particles were studied with synchrotron radiation based micro X-ray fluorescence (SR-[mu]-XRF) spectrometry. Scanning electron microscope equipped with energy dispersive X-ray detector (SEMEDX) and secondary ion mass spectrometer (SIMS) were used to examine particle surfaces. Based on the elemental composition the particles were divided into two groups; particles with plain Pu matrix, and particles where the plutonium is included in Si/O-rich matrix being more heterogeneously distributed. All of the particles were identified as fragments of initial weapons material. As containing plutonium with low 24°Pu/239Pu atomic ratio, ≈2-6%, which corresponds to weapons grade plutonium, the source term was identified to be among the safety tests conducted in the history of Runit Island.

Handbook of Radioactivity Analysis: Radiation Physics and Detectors, Volume One, and Radioanalytical Applications, Volume Two, Fourth Edition, is an authoritative reference on the principles, practical techniques and procedures for the accurate measurement of radioactivity - everything from the very low levels encountered in the environment, to higher levels measured in radioisotope research, clinical laboratories, biological sciences, radionuclide standardization, nuclear medicine, nuclear power, and fuel cycle facilities, and in the implementation of nuclear forensic analysis and nuclear safeguards. It includes sample preparation techniques for all types of matrices found in the environment, including soil, water, air, plant matter and animal tissue, and surface swipes.Users will find a detailed discussion of our current understanding of the atomic nucleus, nuclear stability and decay, nuclear radiation, and the interaction of radiation with matter relating to the best methods for radionuclide detection and measurement. - Spans two volumes, Radiation Physics and Detectors and Radioanalytical Applications - Includes a much-expanded treatment of calculations required in the measurement of radionuclide decay, energy of decay, nuclear reactions, radiation attenuation, nuclear recoil, cosmic radiation, and synchrotron radiation - Includes the latest advances in liquid and solid scintillation analysis, alpha- and gamma spectrometry, mass spectrometric analysis, gas ionization and nuclear track analysis, and neutron detection and measurement - Covers high-sample-throughput microplate techniques and multi-detector assay methods

Endlich ein Fachbuch mit detaillierten Informationen zu einer der fortschrittlichsten Methoden zur Materialcharakterisierung. Ein herausragendes Team aus Herausgebern und Autoren von renommierten Einrichtungen und Institutionen beschäftigt sich mit Synchrotron-Verfahren, die sich in der Materialforschung bewährt haben. Nach einer Einführung in die Synchrotronstrahlung und ihrer Quellen werden die verschiedenen Techniken beschrieben, die von diesem besonders hellen Licht profitieren, u. a. Röntgenabsorption, Diffraktion, Streuung, Bildgebung und Lithographie. Zum Schluss folgt ein Überblick über die Anwendungen der Synchrotronstrahlung in den Materialwissenschaften. Dieses einzigartige, unabdingbare Referenzwerk für akademische Forscher und Forscher aus der Industrie verbindet Spezialisten aus der Synchrotronforschung und Materialwissenschaftler.

This is the first book to cover actinide nano research. It is of interest both for fundamental research into the chemistry and physics of f-block elements as well as for applied researchers such as those studying the long-term safety of nuclear waste disposal and developing remediation strategies. The authors cover important issues of the formation of actinide nano-particles, their properties and structure, environmental behavior of colloids and nanoparticles related to the safe disposal of nuclear wastes, modeling and advanced methods of characterization at the nano-scale.

This PhD sought to determine the mechanisms for the reactor explosions by mapping, collecting and analysing samples from across the area of Japan that received radioactive fallout from the explosions. In doing this, the author conducted significant fieldwork in the restricted-access fallout zone using ground and novel UAV-based mapping of radiation to identify hot-spot areas for sample collecting but also using these tools to verify the efficacy of the clean-up operations ongoing in the prefecture. Such fieldwork was both technically pioneering for its use of UAVs (drones) but also selfless in terms of bravely entering a nuclear danger area to collect samples for the greater benefit of the scientific community.

Studies on the fate and transport of radioactive contaminates in the environment are often constrained by a lack of knowledge on the elemental distribution and general behavior of particulate bound radionuclides contained in hot particles. A number of hot particles were previously isolated from soil samples collected at former U.S. nuclear test sites in the Marshall Islands and characterized using non-destructive techniques [1]. The present investigation at HASYLAB is a part of larger research program at ITU regarding the characterization of environmental radioactive particles different locations and source-terms. Radioactive particles in the environment are formed under a number of different release scenarios and, as such, their physicochemical properties may provide a basis for identifying source-term specific contamination regimes. Consequently, studies on hot particles are not only important in terms of studying the elemental composition and geochemical behavior of hot particles but may also lead to advances in assessing the long-term impacts of radioactive contamination on the environment. Six particles isolated from soil samples collected at the Marshall Islands were studied. The element distribution in the particles was determined by confocal [mu]-XRF analysis using the ANKA FLUO beam line. The CRL (compound refractive lens) was used to focus the exciting beam and the polycapillary half lens to collimate the detector. The dimensions of confocal spot were measured by 'knife edge scanning' method with thin gold structure placed at Si wafer. The values of 3.1 x 1.4 x 18.4 [mu]m were achieved if defined as FWHMs of measured L?intensity profiles and when the19.1 keV exciting radiation was used. The collected XRF spectra were analyzed offline with AXIL [2] software to obtain net intensities of element characteristic lines. Further data processing and reconstruction of element distribution was done with the software 'R' [3] dedicated for statistical calculations. In figure 1 the distributions of Pu, Fe and Ti obtained for one of the studied hot particles are presented. The strongest signal was recorded for plutonium; the signals from iron and titanium are respectively 14 and 38 times less. It means that Pu is the most abundant of the observed elements. However, since the light elements are not detectable with the applied measurement conditions, it cannot be definitely stated if plutonium is the main element present in the sample. The isosurfaces are calculated at 20 % of maximum intensity for each element. Please note that the isosurfaces on the drawing are transparent. Changes in the spatial distribution of Pu, Fe, and Ti within the particle are shown in Fig. 2a, 2b, and 2c. Distinct elemental patterns are clearly visible at the higher concentration levels. The distributions of Cr, Cu, and Pb were also reconstructed but the results are not presented here. As it is shown in Fig. 1, the correlation between elements is good at low concentrations but the maxima of concentrations are not strongly correlated (see Fig. 2.). In general, the particle is inhomogeneous in terms of its elemental composition. Similar inhomogeneities were found for other particles with Pu identified as a major element in three of the six particles examined.

As a result of contamination by radionuclides released during nuclear weapons testing by the United States during the 1940s and 1950s, the residents of Rongelap Atoll were evacuated from the Marshall Islands. This book provides an assessment of issues surrounding their resettlement and an evaluation of radiological conditions on certain Marshall Islands, particularly Rongelap Atoll.

Reports on the outcome of an IAEA coordinated research project in the area of measurement and characterization of radioactive particles in the environment. This publication summarizes the achievements and findings of the project participants and gives guidance for application of the techniques for evaluation of contaminated areas.