The evaluation of radioactivity accidentally released into the atmosphere involves determining the radioactivity levels of rainwater samples. Rainwater scavenges atmospheric airborne radioactivity in such a way that surface contamination can be deduced from rainfall rate and rainwater radioactivity content. For this purpose, rainwater is usually collected in large surface collectors and then measured by gamma-spectrometry after such treatments as evaporation or iron hydroxide precipitation. We found that collectors can be adapted to accept large surface (diameter 47mm) cartridges containing a strongly acidic resin (Dowex AG 88) which is able to quantitatively extract radioactivity from rainwater, even during heavy rainfall. The resin can then be measured by gamma-spectrometry. The detection limit is 0.1Bq per sample of resin (80g) for (137)Cs. Natural (7)Be and (210)Pb can also be measured and the activity ratio of both radionuclides is comparable with those obtained through iron hydroxide precipitation and air filter measurements. Occasionally (22)Na has also been measured above the detection limit. A comparison between the evaporation method and the resin method demonstrated that 2/3 of (7)Be can be lost during the evaporation process. The resin method is simple and highly efficient at extracting radioactivity. Because of these great advantages, we anticipate it could replace former rainwater determination methods. Moreover, it does not necessitate the transportation of large rainwater volumes to the laboratory.
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http://dx.doi.org/10.1016/j.jenvrad.2009.01.006 | DOI Listing |
Environ Technol
January 2025
Shaanxi Huashan Road and Bridge Group Co., Ltd., Xi'an, People's Republic of China.
Due to the rapid development of urbanisation, cities frequently experience waterlogging during rainfall. Rain gardens are widely used in new urban construction because they effectively control surface runoff from rainwater, thereby reducing waterlogging. The runoff control effectiveness of rain gardens is influenced by multiple factors.
View Article and Find Full Text PDFJ Agric Food Chem
January 2025
State Key Laboratory of Coordination Chemistry, Key Laboratory of Mesoscopic Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Facile pesticide nanocapsules were successfully prepared by directly encapsulating the antisolvent precipitation of pesticides through instantaneous "on site" coordination assembly of tannic acid and Fe, avoiding tedious preparation, time consumption, and large amounts of organic solvents. The pesticide nanocapsules showed excellent resistance to ultraviolet photolysis and rainwater washing owing to the nanocapsule walls. The smart pesticide nanocapsules exhibited the controlled release of pesticides under multidimensional stimuli, such as acidic/alkaline pH, glutathione, HO, phytic acid, laccase, tannase, and sunlight, which were related to the physiological and natural environments of crops, pests, and pathogens.
View Article and Find Full Text PDFHeliyon
January 2025
Faculty of Science and Technology, Campus of Banekane, Université des Montagnes, P.O. Box 208, Bangangté, Cameroon.
This article evaluates the prospects for rainwater harvesting (RWH) as a means of optimizing water management in the Mandara Mountains. RWH is a small-scale water conservation approach for locally intercepting and storing rainfall before it enters the usual hydrologic cycle. This ancient practice has recently sustained lives in semiarid areas of the world (e.
View Article and Find Full Text PDFLancet Neurol
February 2025
Department of Clinical Neurological Sciences, University of Western Ontario, London, ON, Canada; Department of Cognitive Neurology, St Joseph's Health Care London, London, ON, Canada. Electronic address:
Background: No treatments exist for apathy in people with frontotemporal dementia. Previously, in a randomised double-blind, placebo-controlled, dose-finding study, intranasal oxytocin administration in people with frontotemporal dementia improved apathy ratings on the Neuropsychiatric Inventory over 1 week and, in a randomised, double-blind, placebo-controlled, crossover study, a single dose of 72 IU oxytocin increased blood-oxygen-level-dependent signal in limbic brain regions. We aimed to determine whether longer treatment with oxytocin improves apathy in people with frontotemporal dementia.
View Article and Find Full Text PDFJ Contam Hydrol
January 2025
Department of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois St, Golden, CO 80401, USA. Electronic address:
Soil samples collected from an aqueous film-forming foam (AFFF)-impacted sandy soil formation at two depth intervals above the water table were used in bench-scale column experiments to evaluate the release of poly- and perfluoroalkyl substances (PFASs) under different degrees of water saturation. Artificial rainwater was applied to the soils under constant and variably saturated conditions. Results from constant saturation experiments suggest that retention of PFAS mass at air-water interfaces was evident in the deep soil (f < 0.
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