Implantation of recoiling radionuclides of U and Th radioactive series applied to estimation of surficial erosion of CaCO3 materials |
| |
| Institution: | 1. C.N.R., Centro di Studio per il Quaternario, e l’Evoluzione Ambientale, c/o Dipartimento di Scienze della Terra, Università La Sapienza-P.le A. Moro 5, 00185 Rome, Italy;2. Istituto di Medicina Sperimentale-C.N.R., Area di Ricerca di Tor Vergata, via del Fosso del Cavaliere 100, 00133 Rome, Italy;3. Via Pierluigi da Palestrina, 79-04100 Latina, Italy;4. Geochenv-via Ugo, Foscolo, 9-00040 Pomezia (Rome), Italy;1. Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia (UTM), 81310 Johor Bahru, Johor, Malaysia;2. School of Chemical Sciences, Univeristy Sains Malaysia, 11800 Minden, Pulau Pinang, Malaysia;3. School of Chemical Sciences & Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia;4. Department of Physics, Faculty of Science, Universiti Teknologi Malaysia (UTM), 81310 Johor Bahru, Johor, Malaysia;1. Swinburne University of Technology, Department of Civil and Construction Engineering, Hawthorn, Victoria, 3122, Australia;2. Department of Civil Engineering, Faculty of Engineering and Architecture, Rajamangala University of Technology Isan, Nakhon Ratchasima 30000, Thailand;3. School of Civil Engineering, and Center of Excellence in Innovation for Sustainable Infrastructure Development, Suranaree University of Technology, Nakhon Ratchasima, Thailand;1. College of Economics and Management, Nanjing University of Aeronautics and Astronautics(NUAA), Nanjing 211100, China;2. School of Economics, Ocean University of China(OUC), Qingdao 266100, China;3. Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo N2L 3G1, Canada;1. Eduardo Torroja Institute for Construction Science (IETcc- C.S.I.C.), E28033, Madrid, Spain;2. CQVR, Department of Engineering, University of Trás-os-Montes e Alto Douro, 5000-801 Vila Real, Portugal;3. ISISE, Department of Civil Engineering, University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal;1. Hebei and China Geological Survey Key Laboratory of Groundwater Remediation, Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, 050061, China;2. Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China |
| |
| Abstract: | A method to detect the extent of rainfall-dependent erosion of CaCO3 materials, based on implantation of recoiling nuclei of U–Th disequilibrium series (UTHIRN) is outlined here. Radon chambers provided natural implantation of short and medium-lived isotopes (212Pb and 210Pb) on surfaces of natural varieties of CaCO3. Equal thicknesses of CaCO3 were dissolved in order to measure the distribution of the recoiled nuclei inside the target material. The measured distribution was found to be consistent with the theoretical distribution expected for mechanisms of nuclear stopping. The 216Po half-recoil range (18 nm) obtained from the experimental curve was slightly higher than the theoretical one (16 nm).The ratio between residual and initial activity, monitored by non-destructive methods, was then used to calculate the eroded thickness of CaCO3 tablets. The ‘chemical’ and ‘mechanical’ contributions of the surficial erosive process were evaluated by leaching experiments and by simulated rainfall, respectively. Successively, the erosion rates produced during single rainfall events were compared with the experimentally obtained rates, using ternary diagrams (pH/ mm of rainfall/eroded thickness). The difference between the total eroded thickness measured by the proposed method (22.5 nm) and the total eroded thickness predicted by the theoretical model (16.9 nm) for the considered rainfalls was about 25%. The temporal resolution of the erosion rate, the extension of monitored area and the detail of the surficial eroded thickness (up to ～40 nm) are notably improved by the UTHIRN method. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
