Absolute Measurement of Thoron in Surface Waters
Thoron (radon-220, <sup>220</sup>Rn, half-life 55.6 s) is a useful aqueous tracer suitable for applications such as locating and measuring groundwater discharge in surface waters (including the coastal ocean) and detecting radium-224 (<sup>224</sup>Ra) bearing scale inside wa...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-11-01
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| Series: | Water |
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| Online Access: | https://www.mdpi.com/2073-4441/12/11/3083 |
| _version_ | 1797548939805720576 |
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| author | Derek Lane-Smith Michael Schubert |
| author_facet | Derek Lane-Smith Michael Schubert |
| author_sort | Derek Lane-Smith |
| collection | DOAJ |
| description | Thoron (radon-220, <sup>220</sup>Rn, half-life 55.6 s) is a useful aqueous tracer suitable for applications such as locating and measuring groundwater discharge in surface waters (including the coastal ocean) and detecting radium-224 (<sup>224</sup>Ra) bearing scale inside water pipes. Generally, such applications require only relative thoron measurements in the water. However, if a thoron-in-water quantification in absolute numbers is desired the knowledge of the thoron sensitivity of the measurement system is obligatory. Absolute readings would, e.g., give a measure of the <sup>224</sup>Ra activity in the sediment, supporting the thoron, or of the quantity of <sup>224</sup>Ra in the pipe scale. Since there is no standardised source of thoron-in-water (such as a NIST standard), there is no way to calibrate a thoron-in-water measurement system, in the usual sense. Up until now, therefore, it has not been possible to make absolute measurements of thoron in water. This paper presents a novel method of assessing the sensitivity of a mobile thoron-in-water measurement system. The paper analyses such systems and describes a straightforward experimental approach to obtain all setup-specific values of critical parameters that will allow a reasonably precise determination of the system thoron sensitivity. The method is simple enough that a thoron sensitivity calibration can be performed on site with no additional equipment. |
| first_indexed | 2024-03-10T15:06:55Z |
| format | Article |
| id | doaj.art-4b5172dc5f124bd9b556406f5fa02ea5 |
| institution | Directory Open Access Journal |
| issn | 2073-4441 |
| language | English |
| last_indexed | 2024-03-10T15:06:55Z |
| publishDate | 2020-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Water |
| spelling | doaj.art-4b5172dc5f124bd9b556406f5fa02ea52023-11-20T19:38:20ZengMDPI AGWater2073-44412020-11-011211308310.3390/w12113083Absolute Measurement of Thoron in Surface WatersDerek Lane-Smith0Michael Schubert1Smith Air Consulting, London, ON N5X 3A1, CanadaUFZ-Helmholtz Centre for Environmental Research, 04318 Leipzig, GermanyThoron (radon-220, <sup>220</sup>Rn, half-life 55.6 s) is a useful aqueous tracer suitable for applications such as locating and measuring groundwater discharge in surface waters (including the coastal ocean) and detecting radium-224 (<sup>224</sup>Ra) bearing scale inside water pipes. Generally, such applications require only relative thoron measurements in the water. However, if a thoron-in-water quantification in absolute numbers is desired the knowledge of the thoron sensitivity of the measurement system is obligatory. Absolute readings would, e.g., give a measure of the <sup>224</sup>Ra activity in the sediment, supporting the thoron, or of the quantity of <sup>224</sup>Ra in the pipe scale. Since there is no standardised source of thoron-in-water (such as a NIST standard), there is no way to calibrate a thoron-in-water measurement system, in the usual sense. Up until now, therefore, it has not been possible to make absolute measurements of thoron in water. This paper presents a novel method of assessing the sensitivity of a mobile thoron-in-water measurement system. The paper analyses such systems and describes a straightforward experimental approach to obtain all setup-specific values of critical parameters that will allow a reasonably precise determination of the system thoron sensitivity. The method is simple enough that a thoron sensitivity calibration can be performed on site with no additional equipment.https://www.mdpi.com/2073-4441/12/11/3083environmental tracerthoron<sup>220</sup>Rnradon<sup>222</sup>Rngroundwater discharge |
| spellingShingle | Derek Lane-Smith Michael Schubert Absolute Measurement of Thoron in Surface Waters Water environmental tracer thoron <sup>220</sup>Rn radon <sup>222</sup>Rn groundwater discharge |
| title | Absolute Measurement of Thoron in Surface Waters |
| title_full | Absolute Measurement of Thoron in Surface Waters |
| title_fullStr | Absolute Measurement of Thoron in Surface Waters |
| title_full_unstemmed | Absolute Measurement of Thoron in Surface Waters |
| title_short | Absolute Measurement of Thoron in Surface Waters |
| title_sort | absolute measurement of thoron in surface waters |
| topic | environmental tracer thoron <sup>220</sup>Rn radon <sup>222</sup>Rn groundwater discharge |
| url | https://www.mdpi.com/2073-4441/12/11/3083 |
| work_keys_str_mv | AT dereklanesmith absolutemeasurementofthoroninsurfacewaters AT michaelschubert absolutemeasurementofthoroninsurfacewaters |