Plutonium-239, 240 atmospheric radioactivity measurements at Mururoa from 1986 to 1991

1994 ◽  
Vol 177 (1) ◽  
pp. 107-120 ◽  
Author(s):  
Y. Bourlat ◽  
J. -C. Millies-Lacroix ◽  
B. Dunoyer
Keyword(s):  
Atmospheric Radioactivity ◽  
Radioactivity Measurements

Atmospheric radioactivity measurements at the SMEAR Estonia Station

2020 ◽  
Author(s):  
Heikki Junninen ◽  
Jussi Paatero ◽  
Urmas Hõrrak ◽  
Xuemeng Chen
Keyword(s):  
Gamma Radiation ◽  
Dose Rate ◽  
Aerosol Particles ◽  
Chem Phys ◽  
Gamma Dose ◽  
Gamma Dose Rate ◽  
Air Ions ◽  
Atmospheric Radioactivity ◽  
Atmospheric Radon ◽  
Radioactivity Measurements

<p>The SMEAR Estonia is a Station for Measuring Ecosystem-Atmosphere Relations (SMEAR). It is built on the same concept as the Finnish SMEAR stations <sup>[1]</sup> and belongs to the same measurement network. It is located in a hemiboreal forest at Järvselja, South-Eastern Estonia (58.2714 N, 27.2703 E at 36 m a.s.l.) <sup>[2]</sup>. The Estonian University of Life Sciences runs long-term measurements on meteorological parameters, trace gases and fluxes at the station. Atmospheric aerosol and air ions measurements are deployed by the University of Tartu (UT). </p><p> </p><p>Our main interest at UT lies in characterising atmospheric ions and aerosols, studying their connections to atmospheric new particle formation and cloud processes, and understanding the impacts of these processes on air quality, local weather and climate. Air ions are known to participate in forming atmospheric new particles <sup>[3]</sup>. Newly formed aerosol particles have the potential to modify cloud properties, once they reach big enough sizes via condensational and coagulational growth<sup>[4]</sup>. Air ions are primarily produced by the ionisation of air molecules, with the ionisation energy provided by natural radioactivity present in the atmosphere. The initial ionisation produces are subject to different dynamic processes, including charge transfer, clustering, coagulation and condensational growth <sup>[5]</sup>. At UT, we are launching a five-year project, starting from Jan. 2020, to investigate how atmosphere transforms the new-born air ions to climatically relevant aerosol particles. In order to get insights into the transformation process, atmospheric radioactivity measurements are crucial together with air ion and aerosol measurements.</p><p> </p><p>In the lower troposphere, ionization of the atmospheric originates from the decay of radon and other radioactive nuclides in the air and the Earth's crust as well as cosmic radiation. In collaboration with the Finnish Meteorological Institute, we initiated atmospheric radioactivity measurements at the SMEAR Estonia. The total gamma radiation (50 keV to 1.3 MeV) is measured with a gamma radiation meter (RADOS RD-02L) (since June 2019). The atmospheric radon is monitored using a filter-based Geiger-Müller counter (since Nov. 2019), which is a one-counter variation of an earlier design<sup>[6]</sup>. Atmospheric radon concentration is determined based on deposited beta activity. Preliminary results show that SMEAR Estonia (mean gamma dose rate = 0.03 uSv/h, mean radon conc. = 2.5 Bq/m<sup>3</sup>) has less ionization than SMEAR II station in Finland (mean gamma dose rate = 0.08 uSv/h, mean radon conc. = 2 Bq/m<sup>3</sup>). The linkage of this observation to air ion properties is under progress.</p><p>References:</p><p>[1]       Hari P., Kulmala M., Boreal Environ. Res. <strong>2005</strong>, 10, 315-322.</p><p>[2]       Noe S. M. et al., Forestry Studies <strong>2015</strong>, 63.</p><p>[3]       Tammet H. et al., Atmospheric Research <strong>2014</strong>, 135-136, 263-273.</p><p>[4]       Merikanto J. et al., Atmos. Chem. Phys. <strong>2009</strong>, 9, 8601-8616.</p><p>[5]       Chen X. et al. Atmos. Chem. Phys. <strong>2016</strong>, 16, 14297-14315.</p><p>[6]       Paatero J. et al., Radiat. Prot. Dosim. <strong>1994</strong>, 54, 33-39.</p>

A compact NaI(Tl) with avalanche photodiode gamma spectrometer for in situ radioactivity measurements in marine environment

2021 ◽  
Vol 92 (3) ◽  
pp. 033301
Author(s):  
Zhenyu Sun ◽  
Fan Zhou ◽  
Zhe Cao ◽  
Ziheng Zhou ◽  
Xiaohu Wang ◽  
...  
Keyword(s):  
Marine Environment ◽  
Avalanche Photodiode ◽  
Gamma Spectrometer ◽  
Radioactivity Measurements

Studying of characteristics of the HPGe detector for radioactivity measurements

2013 ◽  
Vol 8 (10) ◽  
pp. P10027-P10027 ◽  
Author(s):  
D Demir ◽  
M Eroğlu ◽  
A Turşucu
Keyword(s):  
Hpge Detector ◽  
Radioactivity Measurements

The Measurement of Calcium Absorption and Absorption Rate with an External Arm Radioactivity Counter

1978 ◽  
Vol 54 (1) ◽  
pp. 93-97
Author(s):  
R. C. Smart ◽  
C. D. Holdsworth
Keyword(s):  
Absorption Rate ◽  
Calcium Absorption ◽  
Scintillation Counter ◽  
Total Calcium ◽  
Ratio Determination ◽  
Lead Shielding ◽  
Deconvolution Techniques ◽  
Serial Measurements ◽  
Radioactivity Measurements

1. A large-volume scintillation counter was used to measure calcium absorption from the ratio of forearm uptake of 47Ca after oral 47CaCl2 (administered with milk) to forearm uptake after intravenously administered 47CaCl2. 2. In some subjects serial measurements of both forearm uptake of 47Ca and blood 47Ca radioactivity were also recorded, and by using deconvolution both total calcium absorption and calcium absorption rate were determined. 3. The forearm ratio determination of 47Ca absorption correlated well with that obtained by deconvolution of either serial blood 47Ca or forearm 47Ca measurements provided that the forearm radioactivity measurements were made at least 8 h after the administrations of 47CaCl2. 4. Although the two deconvolution techniques gave similar estimates of total calcium absorption there were discrepancies between their measurements of calcium absorption rate. These discrepancies were reduced but not eliminated by the use of additional lead shielding around the Armac counter.

Comparison of radioactivity measurements with radionuclide calibrators in the Republic of Korea

2005 ◽  
Vol 63 (2) ◽  
pp. 201-205 ◽  
Author(s):  
G.-Y. Kim ◽  
H.-K. Lee ◽  
H.K. Jeong ◽  
M.J. Woods
Keyword(s):  
Republic Of Korea ◽  
The Republic ◽  
Radioactivity Measurements
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