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EN
Radioactive aerosols in the confined workplace are a major source of internal exposure hazards for workers. Cloud-type radioactive aerosol elimination system (CRAES) have great potential for radioactive aerosol capture due to their high adsorption capacity, lack of cartridges and less secondary contamination. A CRAES was designed and constructed, and a FeOOH/rGO composite was directly prepared by a hydro-thermal method to characterise and analyse its morphology, chemical structure and removal efficiency for simulated radioactive aerosols. The results show that the FeOOH/rGO composite works in synergy with the CRAES to effectively improve the removal efficiency of simulated radioactive aerosols. A 30-minute simulated radioactive aerosol removal rate of 94.52% was achieved when using the experimentally optimized composite inhibitor amount of 2 mg/L FeOOH/rGO with 0.2 g/L PVA as a surfactant. Therefore, the CRAES coupled with the composite inhibitor FeOOH/rGO has broad application potential for the synergistic treatment of radioactive aerosols.
EN
In this work, source apportionment for unsupported 210Po was conducted. The activity size distributions of both supported and unsupported 210Po in urban aerosols were measured from February to December 2019. The results confirmed that the activity of 210Po in the atmosphere is significantly increased by additional 210Po content related to coal combustion by-product releases, especially in the cold winter season. The sources of this content are local emissions and long-range transport processes. Unsupported activity concentrations of 210Po and weather parameters (temperature, humidity, and wind velocity) were used for source apportionment from three heating systems.
PL
W pracy dokonano podziału źródeł dodatkowych porcji izotopu Po-210. Rozkłady wielkości frakcji zarówno związanej, jak i niezwiązanej Po-210 w aerozolach miejskich mierzono od lutego do grudnia 2019 r. Wyniki potwierdziły, że aktywność Po-210 w atmosferze jest istotnie zwiększona przez dopływ dodatkowych porcji Po-210 związanych z uwalnianiem produktów spalania węgla, zwłaszcza w okresie zimowym. Próbki pobierano w centrum Łodzi, w Polsce. Dwie lokalne elektrownie opalane węglem kamiennym znajdują się około 7 km (205 MW) i 11 km (200 MW) od punktu poboru próbek. W odległości 70 km od punktu poboru próbek znajduje się duża elektrownia na węgiel brunatny (Elektrownia Bełchatów) o mocy 5100 MW. Aerozole zbierano na filtrach z włókna szklanego za pomocą impaktora kaskadowego (TISH). Produkty rozpadu radonu -222, tj. Pb-210, Bi-210 i Po-210 są łatwo adsorbowane na powierzchni cząstek aerozolu zawieszonych w powietrzu i chociaż aktywność 210Pb nie zmienia się znacząco ze względu na stosunkowo długi okres półtrwania wynoszący 22,3 lat, to aktywności Bi-210 i Po-210 przyrastają w czasie przebywania cząstek aerozolu w powietrzu. Temperaturę, wilgotność i prędkość wiatru analizowano wspólnie za pomocą parametru Z, który został zdefiniowany na potrzeby niniejszych badań. Obliczono związane i niezwiązane stężenia aktywności Po-210, a skorelowanie ich z parametrem Z pozwoliło określić ilościowo udział źródeł lokalnej dodatkowej porcji Po-210 i innych źródeł dodatkowej, antropogenicznej emisji Po-210, związanej z transportem dalekiego zasięgu.
EN
Particle size distribution is an important factor governing whether aerosols can be deposited in various respiratory tract regions in humans. Recently, electronic cigarette (EC), as the alternative of tobacco cigarette, has become increasingly popular all over the world. However, emissions from ECs may contribute to both indoor and outdoor air pollution; moreover, comments about their safety remain controversial, and the number of users is increasing rapidly. In this investigation, aerosols were generated from ECs and studied in the indoor air and in a chamber under controlled conditions of radon concentration. The generated aerosols were characterized in terms of particle number concentrations, size, and activity distributions by using aerosol diffusion spectrometer (ADS), diffusion battery, and cascade impactor. The range of ADS assessment was from 10–3 µm to 10 µm. The number concentration of the injected aerosol particles was between 40 000 and 100 000 particles/cm3. The distribution of these particles was the most within the ultrafi ne particle size range (0–0.2 µm), and the other particle were in the size range from 0.3 µm to 1 µm. The surface area distribution and the mass size distribution are presented and compared with bimodal distribution. In the radon chamber, all distributions were clearly bimodal, as the free radon decay product was approximately 1 nm in diameter, with a fraction of 0.7 for a clean chamber (without any additional source of aerosols). The attached fraction with the aerosol particles from the ECs had a size not exceeding 1.0 µm.
EN
The data were collected by the network of the ASS-500 stations, aimed at the detection and monitoring of the presence and activity concentration of radionuclides in the ground-level air in both normal and emergency situation. Results of the monitoring of radionuclide content in the ground-level atmosphere in Poland during the accident in Fukushima Dai-ichi nuclear power plant (FD-NPP) in 2011 are presented. In particular, the results of the measurements cover the period of March–May 2011 focusing on the activity concentration of Cs-137, Cs-136, Cs-134, I-131, I-132 and Te-132. The elevated concentration of radionuclides in the atmosphere was initially detected on 23rd March. The maximum activity concentrations of I-131 – 5.40 mBq/m3 and Cs-137 – 0.73 mBq/m3 were measured on 30th March in Łódź. The ratio of the Cs-134/Cs-137 – 0.82 in Warsaw was calculated for the period 28–30 March. The Fukushima data are compared with the data obtained during the Chernobyl accident and the subsequent period. After the accident in Chernobyl, the maximum measured activity concentration of I-131 reached 180 Bq/m3 on 29th April and Cs-137 – 18 Bq/m3 on 30th April 1986 in Warsaw, however the Cs-134/Cs-137 ratio amounted to 0.49 indicating the presence of the spent fuel of different origin than that of the Fukushima accident. The deposition of the radionuclides from the Fukushima accident does not affect neither Polish people health nor the environment in Poland.
EN
The high volume air sampler AZA-1000 was built in the Environmental Protection Laboratory of the Andrzej Sołtan Institute for Nuclear Studies. In July 2002, this air sampler AZA-1000 was installed in the Polish Polar Observatory of the Polish Academy of Science in Hornsund, Spitsbergen. The device was built with numerous specific features which make possible to operate such station in extra difficult climatic conditions of polar region. Since July 2002, radioactive aerosols were collected at the Petrianov filter tissue FPP-15-1.5 and measured using high resolution g spectrometry in the Environmental Protection Laboratory at Świerk. The concentration of the airborn, cosmogenic radionuclide 7Be and of other natural and man maid radionuclides like 137Cs was determined. A comparison of the preliminary results with those from the ASS-500 sampling station operating at Świder is presented.
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