Az energiaszektor légköri kibocsátásának éghajlati hatása szempontjából fontos primer és szekunder aeroszolok jellemzése = Characterization of primary and secondary aerosols relevant for climate effect of the atmospheric emissions of the energy sector

Az aeroszolrészecskék kémiai összetételének, morfológiájának és heterogenitásának jellemzése érdekében nagyérzékenységű roncsolásmentes mikroanalitikai módszereket fejlesztettünk és alkalmaztunk; a méret szerint frakcionált aeroszol nyomelemtartalmának meghatározásához totálreflexiós röntgenfluoreszcencia-analízist, az ammónium és nitrát mólarányának meghatározásához, valamint a szén és a cink kémiai állapotának vizsgálatához totálreflexiós geometriájú röntgenabszorpciós spektroszkópiát, egyedi részecskék morfológiájának és heterogenitásának jellemzéséhez elektronmikroszkópos méréseket. Kidolgoztuk a velük harmonizáló méret szerint frakcionált aeroszol-mintavételi technikát, lehetővé téve ugyanazon minta mérését mindhárom módszerrel. Megfelelően alacsony kimutatási határuk (< 1 ng/m3) miatt nagyon rövid mintavételi időkkel gyorsan változó légköri folyamatok nyomonkövetését teszik lehetővé. A módszerek teljesítőképességének bemutatását és a projekt keretében vett aeroszol-mintákon való alkalmazását kiegészítettük a másodlagos aeroszol keletkezését figyelembe vevő modellszámításokkal, a koncentrációk és az aeroszol optikai vastagság összevetésével, valamint kutatórepülőgépes mérésekkel. | In order to characterize chemical composition, morphology and heterogeneity of aerosol particles, highly sensitive non-destructive microanalytical methods were developed and applied. Total reflection X-ray fluorescence analysis was used for determination of trace elemental composition of size fractionated aerosol. X-ray absorption spectrometry was used for determination of the molar ratio of ammonium and nitrate, as well as for studying the chemical state of carbon and zinc. A sampling technique was elaborated that harmonizes with the microanalytical methods and allows the collection of size fractionated aerosols. This technique enables the measurement of the same samples with the three microanalytical methods. Because of the sufficiently low detection limits (< 1 ng/m3), the techniques are suitable for tracing of rapidly changing atmospheric processes using extremely short sampling durations. In addition to demonstration of the capabilities of the methods and their application to aerosol samples collected in the framework of the project, atmospheric dispersion model calculations were performed, taking into account the formation of secondary aerosols. The concentrations were compared with aerosol optical thickness data. The sampling apparatus was also tested during research aircraft missions

Ruthenium Oxidation in High Temperature Air and Release of Gaseous Ruthenium KFKI-3/2008

The RUSET experimental programme was launched in order to study Ru oxidation and release from fuel in high temperature air. More than forty small scale tests have been performed with mixed powder components of inactive materials and with short fuel rods. The influence of temperature, air flow rate and the presence of other fission products on the gaseous Ru release and the retention role of fuel pellets and cladding have been investigated. The test series indicated that if an air ingress type severe accident occurs most of the initial Ru mass can be released from the reactor core to the containment or environment. Some part of the released gaseous Ru undergoes precipitation and deposits on the cold surfaces, another part is released in gaseous form. The deposited Ru oxides can serve as a secondary source for further gaseous Ru releas

Nagyfelbontású aszály detektálás űrfelvételek tér- és időbeli fúziójával

Nagyfelbontású aszály detektálás űrfelvételek tér- és időbeli fúziójáva

Edms model verification considering remarkable changes in airport traffic system

This paper presents the verification process of the Emission and Dispersion Modeling System adapted to evaluate the air quality of Liszt Ferenc International Airport. One receptor point was selected at the Airport, at Terminal Building 2 for the analysis, where an air quality monitoring station has been operating. Modeling results completed with background concentrations generated from another suburban monitoring station were compared with measured hourly concentrations using statistical indicators for three compounds (CO, NOX and PM10). Acceptable correlation coefficients (0.53-0.76) were obtained, however modeled PM10 concentrations were significantly underestimated. Pollution roses were generated that highlighted the areal distribution of the pollution sources influencing air quality at the receptor point. The contribution of aircraft movement and apron area emission was found to be well rated, but in case of CO and NOX small (17%) deficiency was found for ground vehicles emission, moreover a much higher (65%) difference was obtained for PM10 2018 Hungarian Meteorological Service.Scopu

Highly Time-Resolved Apportionment of Carbonaceous Aerosols from Wildfire Using the TC–BC Method: Camp Fire 2018 Case Study

The Camp Fire was one of California’s deadliest and most destructive wildfires, and its widespread smoke threatened human health over a large area in Northern California in November 2018. To analyze the Camp Fire influence on air quality on a 200 km distant site in Berkeley, highly time-resolved total carbon (TC), black carbon (BC), and organic carbon (OC) were measured using the Carbonaceous Aerosol Speciation System (CASS, Aerosol Magee Scientific), comprising two instruments, a Total Carbon Analyzer TCA08 in tandem with an Aethalometer AE33. During the period when the air quality was affected by wildfire smoke, the BC concentrations increased four times above the typical air pollution level presented in Berkeley before and after the event, and the OC increased approximately ten times. High-time-resolution measurements allow us to study the aging of OC and investigate how the characteristics of carbonaceous aerosols evolve over the course of the fire event. A higher fraction of secondary carbonaceous aerosols was observed in the later phase of the fire. At the same time, the amount of light-absorbing organic aerosol (brown carbon) declined with time

High-time-resolution carbonaceous aerosols fingerprint using an advanced total carbon–black carbon (TC-BC(λ)) method in Greater Paris, France

International audienc

Contribution of black carbon and desert dust to aerosol absorption in the atmosphere of the Eastern Arabian Peninsula

Discriminating the absorption coefficients of aerosol mineral dust and black carbon (BC) in different aerosol size fractions is a challenge because of BC\u27s large mass absorption cross-section compared to dust. Ambient aerosol wavelength dependent absorption coefficients ($b_{abs}$) in supermicron and submicron size fractions were determined with a high time resolution. The measurements were performed simultaneously using identical systems at an urban and a regional background site in Qatar. At each site, measurements were taken by co-located Aethalometers, one with a virtual impactor (VI) and the other with a PM1 cyclone to respectively collect super-micron-enhanced and submicron fractions. The combined measurement of aerosol absorption and scattering coefficients enabled the particles to be classified based on their optical properties\u27 wavelength dependence. The classification reveals the presence of BC internally/externally mixed with different aerosols. Helium ion microscopy images provided information concerning the extent of mineral dust in the submicron fraction. The determination of absorption coefficients during dust storms and non-dust periods was used to establish the absorption Ångström exponent for dust and BC. Non-parametric wind regression, potential source contribution function and back-trajectory analysis reveal major regional sources of desert dust associated with north-westerly winds and a minor local dust contribution. In contrast, major BC sources found locally were associated with south-westerly winds with a smaller contribution made by offshore emissions transported by north-easterly and easterly winds. The use of a pair of Aethalometers with VI and PM1 inlets separates contributions of BC and dust to the aerosol absorption coefficient