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Abstract  

In recent years, environmental concerns regarding antimony have grown considerably due to anthropogenic processes that have resulted in increasing concentration of Sb in the environment, and also because of its impacts and possible adverse effects to living organisms. Several techniques have been used, to obtain reliable results for Sb, since Sb is present at low level concentration, requiring analytical instrumentation with low detection limits. The neutron activation analysis (NAA) technique has a high metrological level for the determination of several elements in different matrices. However, Sb determination in environmental and biological samples presents some analytical difficulties due to its low concentrations and gamma ray spectrum interferences. The objective of this research was to study on Sb determination in environmental reference materials by NAA. Ten environmental reference materials were selected and analyzed using long period irradiation at IEA-R1 research nuclear reactor. The induced gamma activities of 122Sb and 124Sb were measured. Relative errors of the results demonstrated that the accuracy depends mainly on Sb radioisotope measured, the decay time for counting and the sample composition.

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Abstract  

A method is described for the determination of 90Sr in environmental samples using combination of developed in-house method, Eichrom Sr resin and Beta Counter. Strontium was efficiently, rapidly and simply separated from Ca and other interfering matrix components by Eichrom Sr resin. All the results in general showed good accuracy, high precision, reliable and in good agreement between these two measured and certified value of SRM (i.e. IAEA-375, IAEA-326, IAEA-152 and IAEA-414). As a whole, the procedure described in this work notably improves conventional methods in particular concerning the time needed, sample volume, safer and others. Thus, the introduced method was successfully performed and will be applied to actual sample for the determination of 90Sr in different environmental materials such as soil, sediments, milk, biological sample, water etc.

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Abstract  

The measurement of fission product cesium isotopes 135Cs and 137Cs at low femtogram (fg) 10−15 levels in ground water by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) is reported. To eliminate the natural barium isobaric interference on the cesium isotopes, in-line chromatographic separation of the cesium from barium was performed followed by high sensitivity ICP-MS analysis. A high efficiency desolvating nebulizer system was employed to maximize ICP-MS sensitivity ~10 cps/fg. The three sigma detection limit for 135Cs was 2 fg/mL (0.1 μBq/mL) and for 137Cs 0.9 fg/mL (0.0027 Bq/mL) measured from the standard with analysis time of less than 30 min/sample. Cesium detection and 135/137 isotope ratio measurement at very low femtogram levels using this method in a spiked ground water matrix is also demonstrated.

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, A. , Felder-Casagrande , S. , Foster , G. and Odlyha , M. , “ Development of Environmentally Benign Coatings based on Artists' Materials ” in Preprints 11th Congress on Thermal Analysis and Calorimetry, Philadelphia 1996 , p. 359

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Abstract  

A new rapid method for the determination of actinides and radiostrontium in vegetation samples has been developed at the Savannah River Site Environmental Lab (Aiken, SC, USA) that can be used in emergency response situations or for routine analysis. The actinides in vegetation method utilizes a rapid sodium hydroxide fusion method, a lanthanum fluoride matrix removal step, and a streamlined column separation process with stacked TEVA, TRU and DGA Resin cartridges. Lanthanum was separated rapidly and effectively from Am and Cm on DGA Resin. Alpha emitters are prepared using rare earth microprecipitation for counting by alpha spectrometry. The purified 90Sr fractions are mounted directly on planchets and counted by gas flow proportional counting. The method showed high chemical recoveries and effective removal of interferences. The actinide and 90Sr in vegetation sample analysis can be performed in less than 8 h with excellent quality for emergency samples. The rapid fusion technique is a rugged sample digestion method that ensures that any refractory actinide particles or vegetation residue after furnace heating is effectively digested.

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Abstract  

Some frontiers of environmental radioactivity are outlined where radioecologists and chemists are required to solve environmental problems. The first theme is the need for research on biogeochemical cycling of both stable and radioactive nuclides. The second theme discusses measurement challenges in radioecology. The third theme is related to predictive abilities where much of the present radioecology work is aimed at estimates of impacts in the future. These three themes are linked because our predictive abilities of radionuclide transport require a better knowledge of nuclide cycling, and nuclide cycling can only be studied with the availability of good measurement techniques.

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Abstract  

As part of Canada’s international commitment for the collective defence of allied nations, nuclear submarines from allied nations berth at three approved locations on both east and west coasts of Canada. In the case of any untoward event, a nuclear emergency response (NER) organisation has been established. In addition, regular sampling of the coastal environment is undertaken as the Environmental Radionuclide Monitoring Programme (ERMP). This continuing effort consists of a long-term programme and a visit sub-programme. In the former, samples are ocean sediment, seawater, aquatic plants and sealife; in the latter, samples are seawater taken before, during and after each visit. Samples are collected according to a prescribed schedule and follow a chain of custody to the accredited laboratory in the SLOWPOKE-2 Facility at RMC. Counting and analyses are done by gamma-ray spectroscopy by the Analytical Services Group (ASG) at RMC. With most results below detection limit, the safety of the NPV visits is assured.

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Abstract  

Environmental radiation monitoring in Korea can be categorized as (1) nationwide monitoring program and (2) monitoring program for nuclear facilities. The former is designed to quickly detect any abnormal situation in environmental radioactivity levels. The latter has the objective of evaluating environmental radioactivity levels resulting from the operation of nuclear facilities. This paper describes the two monitoring programs, how they are implemented, items of being measured, analytical techniques, quality control programs and R&D activities associated with the monitoring. Also, some of the latest data obtained by the monitoring programs are introduced.

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Abstract  

Activation analysis in various modifications is one of the most frequently applied analytical methods for environmental research. The method is widely used for routine analysis but its specific approaches allow it to be used for very special research that can hardly be done by other methods. This review gives a brief survey of some examples.

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Abstract  

Two programmes of work are described involving the measurement of environmental pollution over periods from two hours to many years. The long period measurements are deduced from neutron activation analysis of whole wood samples taken from individual tree rings for trees grown in various locations, and some results for cadmium, antimony and germanium levels are reported. In a second series of experiments the concentration of airborne particulate matter is being measured using a moving filter (streak sampler) technique to give a continuous record with two hour resolution. The filter samples are being analysed by proton induced X-ray emission (PIXE) and preliminary data is presented.

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