High efficiency and portable monitor of atmospheric radon concentration activity for environmental applications

Author(s):  
Roger Curcoll Masanes ◽  
Claudia Grossi ◽  
Arturo Vargas

<p>The natural radioactive noble gas radon (<sup>222</sup>Rn) is originated from the decay of radium into the soil and then continuously exhaled to the lower atmosphere. Its diffusion and exhalation rate depend both on the physical and environmental conditions of the soil layers and on the meteorological conditions. With a half-life of 3.8 days and a very limited chemical activity, the <sup>222</sup>Rn is nowadays being used as an atmospheric tracer for: i) the improvement of atmospheric transport models used, among others, to identify greenhouse gas (GHG) emission sources; ii) for the indirect estimation of GHG fluxes by the Radon Tracer Method (RTM). These previous applications need high sensitivity and precision at low radon concentrations range (< 100 Bq m<sup>-3</sup>).</p><p>A new monitor, based on alpha spectrometry of <sup>218</sup>Po electrostatically collected on a PIPs detector, has been designed and developed at the Institute of Energy Technologies (INTE) of the Universitat Politecnica de Catlunya (UPC)  in the mark of the project ‘High efficiency monitor of atmospheric radon concentration for radiation protection and environmental applications (MARE<sup>2</sup>EA), reference: 2019-LLAV-00035, funded by the Catalan Agency for Management of University and Research Grants. The aim is building an instrument able to measure atmospheric radon concentration activities with high precision in order to be running at GHG atmospheric networks for the RTM applications.</p><p>The monitor is an improved version of a previous prototype instrument (Grossi et al., 2012, 2020). The new instrument will allow a higher efficiency, robustness and portability. In addition, it will have a GUI interface to be user friendly. Finally, in order to reduce the air sample humidity within the detection volume of the instrument which affects the <sup>218</sup>Po collection, a portable drying system has also been built to keep the instrument ongoing without maintenance during several weeks.</p><p> </p><p><strong>References</strong></p><p>Grossi, C., Arnold, D., Adame, J. A., López-Coto, I., Bolívar, J. P., De La Morena, B. A., & Vargas, A. (2012). Atmospheric 222Rn concentration and source term at El Arenosillo 100 m meteorological tower in southwest Spain. Radiation Measurements, 47(2), 149–162. https://doi.org/10.1016/j.radmeas.2011.11.006</p><p>Grossi, C., Chambers, S. D., Llido, O., Vogel, F. R., Kazan, V., Capuana, A., Werczynski, S., Curcoll, R., Delmotte, M., Vargas, A., Morguí, J.-A., Levin, I., & Ramonet, M. (2020). Intercomparison study of atmospheric <sup>222</sup>Rn and <sup>222</sup>Rn progeny monitors. Atmospheric Measurement Techniques, 13(5). https://doi.org/10.5194/amt-13-2241-2020</p>

2020 ◽  
Vol 13 (5) ◽  
pp. 2241-2255
Author(s):  
Claudia Grossi ◽  
Scott D. Chambers ◽  
Olivier Llido ◽  
Felix R. Vogel ◽  
Victor Kazan ◽  
...  

Abstract. The use of the noble gas radon (222Rn) as a tracer for different research studies, for example observation-based estimation of greenhouse gas (GHG) fluxes, has led to the need of high-quality 222Rn activity concentration observations with high spatial and temporal resolution. So far a robust metrology chain for these measurements is not yet available. A portable direct atmospheric radon monitor (ARMON), based on electrostatic collection of 218Po, is now running at Spanish stations. This monitor has not yet been compared with other 222Rn and 222Rn progeny monitors commonly used at atmospheric stations. A 3-month intercomparison campaign of atmospheric 222Rn and 222Rn progeny monitors based on different measurement techniques was realized during the fall and winter of 2016–2017 to evaluate (i) calibration and correction factors between monitors necessary to harmonize the atmospheric radon observations and (ii) the dependence of each monitor's response in relation to the sampling height and meteorological and atmospheric aerosol conditions. Results of this study have shown the following. (i) All monitors were able to reproduce the atmospheric radon variability on a daily basis. (ii) Linear regression fits between the monitors exhibited slopes, representing the correction factors, between 0.62 and 1.17 and offsets ranging between −0.85 and −0.23 Bq m−3 when sampling 2 m above ground level (a.g.l.). Corresponding results at 100 m a.g.l. exhibited slopes of 0.94 and 1.03 with offsets of −0.13 and 0.01 Bq m−3, respectively. (iii) No influence of atmospheric temperature and relative humidity on monitor responses was observed for unsaturated conditions at 100 m a.g.l., whereas slight influences (order of 10−2) of ambient temperature were observed at 2 m a.g.l. (iv) Changes in the ratio between 222Rn progeny and 222Rn monitor responses were observed under very low atmospheric aerosol concentrations. Results also show that the new ARMON could be useful at atmospheric radon monitoring stations with space restrictions or as a mobile reference instrument to calibrate in situ 222Rn progeny monitors and fixed radon monitors. In the near future a long-term comparison study between ARMON, HRM, and ANSTO monitors would be useful to better evaluate (i) the uncertainties of radon measurements in the range of a few hundred millibecquerels per cubic meter to a few becquerels per cubic meter and (ii) the response time correction of the ANSTO monitor for representing fast changes in the ambient radon concentrations.


2019 ◽  
Author(s):  
Claudia Grossi ◽  
Olivier Llido ◽  
Felix R. Vogel ◽  
Victor Kazan ◽  
Alessandro Capuana ◽  
...  

Abstract. The use of the noble gas radon (222Rn) as tracer for different research studies, for example observation-based estimation of greenhouse gas (GHG) fluxes, has led to the need of high-quality 222Rn activity concentration observations with high spatial and temporal resolution. So far a robust metrology chain for these measurements is not yet available. A 3-month inter-comparison campaign of atmospheric 222Rn and 222Rn progeny monitors based on different measurement techniques was realized during the fall and winter of 2016-2017 to evaluate: i) calibration and correction factors between monitors necessary to harmonize the atmospheric radon observations; and ii) the dependence of each monitor’s response in relation to the sampling height, meteorological and atmospheric aerosol conditions. Results of this study have shown that: i) all monitors were able to reproduce the atmospheric radon variability on daily basis; ii) linear regression fits between the monitors exhibited slopes between 0.62 and 1.17 and offsets ranging between −0.85 Bq m−3 and −0.23 Bq m−3 when sampling 2 m above ground level (a.g.l.). Corresponding results at 100 m a.g.l. exhibited slopes of 0.94 and 1.03 with offsets of −0.13 Bq m−3 and 0.01 Bq m−3, respectively; iii) no influence of atmospheric temperature and relative humidity on monitor responses was observed for unsaturated conditions; and iv) changes of the ratio between radon progeny and radon monitor responses were observed under very high atmospheric humidity and under very low atmospheric aerosol concentrations. However, a more statistically robust evaluation of these last influences based on a longer dataset should be conducted to improve the harmonization of the data.


2019 ◽  
Vol 26 (11) ◽  
pp. 1946-1959 ◽  
Author(s):  
Le Minh Tu Phan ◽  
Lemma Teshome Tufa ◽  
Hwa-Jung Kim ◽  
Jaebeom Lee ◽  
Tae Jung Park

Background:Tuberculosis (TB), one of the leading causes of death worldwide, is difficult to diagnose based only on signs and symptoms. Methods for TB detection are continuously being researched to design novel effective clinical tools for the diagnosis of TB.Objective:This article reviews the methods to diagnose TB at the latent and active stages and to recognize prospective TB diagnostic methods based on nanomaterials.Methods:The current methods for TB diagnosis were reviewed by evaluating their advantages and disadvantages. Furthermore, the trends in TB detection using nanomaterials were discussed regarding their performance capacity for clinical diagnostic applications.Results:Current methods such as microscopy, culture, and tuberculin skin test are still being employed to diagnose TB, however, a highly sensitive point of care tool without false results is still needed. The utilization of nanomaterials to detect the specific TB biomarkers with high sensitivity and specificity can provide a possible strategy to rapidly diagnose TB. Although it is challenging for nanodiagnostic platforms to be assessed in clinical trials, active TB diagnosis using nanomaterials is highly expected to achieve clinical significance for regular application. In addition, aspects and future directions in developing the high-efficiency tools to diagnose active TB using advanced nanomaterials are expounded.Conclusion:This review suggests that nanomaterials have high potential as rapid, costeffective tools to enhance the diagnostic sensitivity and specificity for the accurate diagnosis, treatment, and prevention of TB. Hence, portable nanobiosensors can be alternative effective tests to be exploited globally after clinical trial execution.


Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 667
Author(s):  
Pavel Rudenko ◽  
Yuriy Vatnikov ◽  
Nadezhda Sachivkina ◽  
Andrei Rudenko ◽  
Evgeny Kulikov ◽  
...  

Despite the introduction of modern methods of treatment, the creation of new generations of antibacterial agents, and the constant improvement of aseptic and antiseptic methods, the treatment of purulent–inflammatory processes remains one of the most complex and urgent problems in veterinary practice. The article presents the results of the isolation of indigenous microbiota from various biotopes of healthy cats, as well as the study of their biological marker properties for the selection of the most optimal strains in probiotic medicines for the control of surgical infections. It was demonstrated that isolated cultures of bifidobacteria and lactobacilli, which we isolated, revealed high sensitivity to antibiotics of the β-lactam group (excepting L. acidophilus No. 24, L. plantarum “Victoria” No. 22, L. rhamnosus No. 5, L. rhamnosus No. 20, and L. rhamnosus No. 26, which showed a significant variability in sensitivity to antibacterial drugs of this group, indicating the great potential of these microorganisms) and resistance to aminoglycosides, lincosamides, and fluoroquinolones (with the exception of gatifloxacin, which showed high efficiency in relation to all lactic acid microorganisms). The adhesive properties of the isolated lactobacteria and bifidobacteria were variable, even within the same species. It was found that the B. adolescentis No. 23 strain of the Bifidobacterium genus, as well as the L. plantarum No. 8, L. plantarum “Victoria” No. 22, L. rhamnosus No. 6, L. rhamnosus No. 26, L. acidophilus No. 12, and L. acidophilus No. 24 strains of the Lactobacillus genus had the highest adhesive activity. Thus, when conducting a detailed analysis of the biological marker properties of candidate cultures (determining their sensitivity to antimicrobial agents, studying the adhesive properties, and antagonistic activity in relation to causative agents of surgical infection in cats), it was found that the most promising are L. plantarum “Victoria” No. 22, L. rhamnosus No. 26, and L. acidophilus No. 24.


2008 ◽  
Vol 8 (10) ◽  
pp. 2811-2832 ◽  
Author(s):  
K. Zhang ◽  
H. Wan ◽  
M. Zhang ◽  
B. Wang

Abstract. The radioactive species radon (222Rn) has long been used as a test tracer for the numerical simulation of large scale transport processes. In this study, radon transport experiments are carried out using an atmospheric GCM with a finite-difference dynamical core, the van Leer type FFSL advection algorithm, and two state-of-the-art cumulus convection parameterization schemes. Measurements of surface concentration and vertical distribution of radon collected from the literature are used as references in model evaluation. The simulated radon concentrations using both convection schemes turn out to be consistent with earlier studies with many other models. Comparison with measurements indicates that at the locations where significant seasonal variations are observed in reality, the model can reproduce both the monthly mean surface radon concentration and the annual cycle quite well. At those sites where the seasonal variation is not large, the model is able to give a correct magnitude of the annual mean. In East Asia, where radon simulations are rarely reported in the literature, detailed analysis shows that our results compare reasonably well with the observations. The most evident changes caused by the use of a different convection scheme are found in the vertical distribution of the tracer. The scheme associated with weaker upward transport gives higher radon concentration up to about 6 km above the surface, and lower values in higher altitudes. In the lower part of the atmosphere results from this scheme does not agree as well with the measurements as the other scheme. Differences from 6 km to the model top are even larger, although we are not yet able to tell which simulation is better due to the lack of observations at such high altitudes.


2006 ◽  
Vol 21 (6) ◽  
pp. 1064-1072 ◽  
Author(s):  
Yumi Yasuoka ◽  
George Igarashi ◽  
Testuo Ishikawa ◽  
Shinji Tokonami ◽  
Masaki Shinogi

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Akbar Abbasi ◽  
Hesham M.H. Zakaly ◽  
Mahmoud M. Hessien

Abstract Radon (222Rn) exposure in the environment is an important issue, and many pathways exist for radon exposure to humans. One of these pathways is 222Rn release through the consumption of natural gas. The issues of 222Rn concentration measurement techniques and worldwide concentration distribution were reviewed in natural gas, with emphasis on performing an active method to determine 222Rn concentration in LPG and CNG gases used in Cyprus. The obtained results were compared with 222Rn concentration in natural gas worldwide and UNSCEAR reports. The average 222Rn concentration value in LPG gas was observed higher than CNG gas. Also, the 222Rn concentration in LPG and CNG gases was less than the UNSCEAR reported value.


Author(s):  
Yusuke Arashida ◽  
Atsushi Taninaka ◽  
Takayuki Ochiai ◽  
Hiroyuki Mogi ◽  
Shoji YOSHIDA ◽  
...  

Abstract We have developed a multiplex Coherent anti-Stokes Raman scattering (CARS) microscope effective for low-wavenumber measurement by combining a high-repetition supercontinuum light source of 1064 nm and an infrared high-sensitivity InGaAs diode array. This system could observe the low-wavenumber region down to 55 cm-1 with high sensitivity. In addition, using spectrum shaping and spectrum modulation techniques, we simultaneously realized a wide bandwidth (<1800 cm-1), high wavenumber resolution (9 cm-1), high efficiency, and increasing signal to noise ratio by reducing the effect of the background shape in low-wavenumber region. Spatial variation of a sulfur crystal phase transition with metastable states was visualized.


2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Daichi Iwata ◽  
Hiroyuki Nagahama ◽  
Jun Muto ◽  
Yumi Yasuoka

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