Semi-continuous measurement of the unattached radon decay products size distributions from 0.5 to 5nm by an array of annular diffusion channels

Autor: G. Tymen, N. Michielsen
Přispěvatelé: Laboratoire de Physique et de Métrologie des Aérosols (DSU/SERAC/LPMA), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Université européenne de Bretagne - European University of Brittany (UEB)
Rok vydání: 2007
Předmět:
Inverse problems
Radon decay products
radon isotope
Atmospheric Science
geometry
Environmental Engineering
Materials science
radioisotope decay
010504 meteorology & atmospheric sciences
aerosol
Particle size analysis
Inverse transform sampling
chemistry.chemical_element
Radon
010501 environmental sciences
01 natural sciences
Diffusion
size distribution
measurement method
Sampling
radiation monitor
0105 earth and related environmental sciences
particulate matter
[PHYS]Physics [physics]
Fluid Flow and Transfer Processes
environmental radioactivity
algorithm
EVE algorithm
Mechanical Engineering
Detector
article
radon 222
radon
particle size
Inverse problem
Pollution
Aerosol
Computational physics
Annular diffusion channels
priority journal
chemistry
Diffusion batteries
Unattached fraction
Particle-size distribution
Nanoparticles
radon 222 daughter
Particle size
Deconvolution
radiation monitoring
Zdroj: Journal of Aerosol Science
Journal of Aerosol Science, 2007, 38 (11), pp.1129-1139. ⟨10.1016/j.jaerosci.2007.08.008⟩
ISSN: 0021-8502
DOI: 10.1016/j.jaerosci.2007.08.008
Popis: A new diffusion battery was designed to make precise measurements of the indoor activity size distribution of short-lived 222Rn decay products in the size range of 0.5-5 nm. It relies on the selection of particles by five annular diffusion channels (ADCs) and on the use of a non-linear inversion method, EVE, for the reconstruction of the particle size distributions. The ADC geometry proved to allow a better selection of the particles size compared to the wire screen and the implementation of an alpha detector set in front of the sampling filter for semi-continuous activity measurements. EVE algorithm was chosen in order to take into account the uncertainties of the measurement in the deconvolution process. The diffusion battery was tested in a radon chamber, and results showed a good reproducibility of the measurements. The degree of confidence on the obtained size distributions is then discussed. Results show that the relative uncertainty on the penetration data has to be less than 10% in order to obtain a reliable size distribution. © 2007 Elsevier Ltd. All rights reserved.
Databáze: OpenAIRE
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