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Utjecaj atmosferskih lebdećih čestica na ljudsko zdravlje
Katja Džepina, 2018, objavljeni povzetek znanstvenega prispevka na konferenci (vabljeno predavanje)

Opis: Kvalitetu zraka u današnjem svijetu određuju ljudske aktivnosti iz kojih nastaje antropogeno zagađenje zraka. Utjecaj antropogenog zagađenja na kvalitetu zraka snažno se povećao od početka industrijske revolucije prije cc 150 godina. Na globalnom nivou, smanjenje kvalitete zraka u svijetu nakon pre-industrijskih vremena nepobitno uzrokuje zagrijavanje planeta Zemlje zbog ljudskih aktivnosti, kako je nedavno objavljeno i u izvještaju Međunarodnog panela za promjenu klime (eng. Intergovernmental Panel for Climate Change, IPCC). Ljudi posebno izloženi lošoj kvaliteti zraka su oni koji žive u područjima gdje standardi kvalitete zraka ne postoje ili se ne sprovode, poput ljudi koji žive pored izvora zagađenja ili u društvima koja se razvijaju. Tijekom zime 2017. - 2018. u periodu kada se po dostupnim podacima događaju epizode najgore kvalitete zraka u Kantonu Sarajevo (4. decembar 2017. – 15. mart 2018.) u Kantonu Sarajevo odvila su se terenska mjerenja sastojaka atmosfere u sklopu kampanje SAFICA 2017-2018 (“Sarajevo Canton Winter Field Campaign 2017-2018“). SAFICA projekt vodili su Federalni hidrometeorološki zavod BiH, Zavoda za javno zdravstvo Kantona Sarajeva, Univerzitet u Sarajevu i Sveučilište u Rijeci, a mjerenja su se odvijala na tri urbane lokacije unutar grada Sarajeva (Otoka, Pofalići i Bjelave) i jednoj pozadinskoj (planinski prijevoj Ivan Sedlo). U ovom predavanju, objasnit će se osnove antropogenog zagađenja zraka i njegovog globalnog utjecaja na kvalitetu zraka, i dati primjeri različitih kvaliteta zraka u modernim društvima kao i u onima koja se tek razvijaju. Posebna pažnja bit će posvećena atmosferskim lebdećim česticama i objasnit će se njihov nastanak i važnost parametara čestica poput atmosferske koncentracije, veličine i kemijskog sastava. Također, dat će se prikaz negativnog utjecaja čestica na ljudsko zdravlje i objasniti zašto su atmosferske koncentracije sitnih atmosferskih čestica linearno korelirane sa smrtnošću ljudi. Konačno, predstavit će se preliminarni rezultati mjerenja sastojaka atmosfere u kantonu Sarajevo tijekom SAFICA kampanje i usporedit sa rezultatima iz drugih svjetskih urbanih područja.
Ključne besede: Atmosferske lebdeće čestice, Antropogeno zagađenje zraka, Sarajevo, Bosna i Hercegovina, SAFICA 2018
Objavljeno v RUNG: 27.05.2021; Ogledov: 2219; Prenosov: 0
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14.
Chemical characterization of atmospheric aerosols in the Sarajevo Canton : results of 2017-2018 Sarajevo Canton Winter Field Campaign (SAFICA)
Katja Džepina, 2018, objavljeni povzetek znanstvenega prispevka na konferenci (vabljeno predavanje)

Opis: The World Health Organization (WHO) identified air pollution as the world’s largest single environmental health risk causing seven million deaths per year, one in eight deaths globally. Of particular concern are heavily polluted and understudied urban centres: while thousands of scientific papers have been published on air quality of the cities such as London, UK and Los Angeles, USA, only 41 papers exist on the top 10 globally most polluted cities. Sarajevo, the capital of Bosnia and Herzegovina (B&H), is one of urban centres which often experiences low air quality due to the extensive use of non-renewable energy sources and geographical location. For example, in Sarajevo during 2010, an annual average concentration of particulate matter (PM) with a diameter smaller than 10 µm (PM10) was 50 µg/m3, a value 2.5x higer than the recommended WHO guidelines value of 20 µg/m3. Sarajevo Canton Winter Field Campaign 2017-2018 (SAFICA) took place in the Sarajevo Canton during the cold winter season of 2017 – 2018 (Dec 4, 2017 – Mar 15, 2018), the period historically characterized with the lowest air quality according to the available data. SAFICA project was lead by Federal hydrometeorological Institute of B&H, Institute of Public Health of the Sarajevo Canton, University of Sarajevo and University of Rijeka, and field measurements took place at three urban locations within the city of Sarajevo (Otoka, Pofalići i Bjelave) i one remote location (Ivan Sedlo mountain ridge). In this presentation, the basics of anthropogenic air pollution and its global influece on the air quality will be explained. Particular attention will be given to the atmospheric PM or aerosols, and aerosols formation mechanisms and the importance of their characteristics such as atmospheric concentration, size and chemical composition will be explained. Also, the reasons for the adverse effects of aerosols on human health and the correlation of atmospheric fine PM (PM2.5) concentrations and human mortality will be explained. Finally, preliminary results of SAFICA measurements campaign will be presented and compared with those from other global urban centers.
Ključne besede: atmospheric aerosol, Sarajevo, urban air pollution, SAFICA 2018
Objavljeno v RUNG: 26.05.2021; Ogledov: 2193; Prenosov: 0
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15.
Molekularna karakterizacija lebdećih čestica slobodne troposfere sa Opservatorija Pico planine
Katja Džepina, Claudio Mazzoleni, Paulo Fialho, Swarup China, B. Zhang, R. Chris Owen, D. Helmig, J. Hueber, Sumit Kumar, J. A. Perlinger, 2017, objavljeni povzetek znanstvenega prispevka na konferenci

Opis: Long-range transported free tropospheric aerosol was sampled at the PMO (38°28’15’’N, 28°24’14’’W; 2225 m amsl) on Pico Island of the Azores in the North Atlantic. Filter-collected aerosol during summer 2012 was analysed for organic and elemental carbon, and inorganic ions. The average aerosol ambient concentration was 0.9 µg m-3. Organic aerosol contributed the majority of mass (57%), followed by sulphate (21%) and nitrate (17%). Filter-collected aerosol was positively correlated with on-line aerosol measurements of black carbon, light scattering and number concentration. Water-soluble organic compounds (WSOC) from 9/24 and 9/25 samples collected during a pollution event were analysed with ultrahigh-resolution FT-ICR MS. FLEXPART analysis showed the air masses were very aged (>12 days). ~4000 molecular formulas were assigned to each of the mass spectra between m/z 100-1000. The majority of the assigned molecular formulas have unsaturated structures with CHO and CHNO elemental compositions. WSOC have an average O/C of ~0.45, relatively low compared to O/C of other aged aerosol, which might be the result of evaporation and fragmentation during long-range transport. The increase in aerosol loading during 9/24 was linked to biomass burning emissions from North America by FLEXPART and MODIS fire counts. This was confirmed with WSOC biomass burning markers and with the morphology and mixing state of particles as determined by SEM. The presence of markers characteristic of aqueous-phase reactions of biomass burning phenolic species suggests that the aerosol collected at Pico had undergone cloud processing. The air masses on 9/25 were more aged (~15 days) and influenced by marine emissions, as indicated by organosulphates and species characteristic for marine aerosol (e.g. fatty acids). The change in air masses for the two samples was corroborated by the changes in ozone, ethane, propane, morphology of particles, as well as by FLEXPART. In this presentation we will presents the first detailed molecular characterization of free tropospheric aged aerosol intercepted at the PMO.
Ključne besede: Atmospheric aerosol, Free troposphere, Mass spectrometry, Pico mountain observatory
Objavljeno v RUNG: 26.05.2021; Ogledov: 2530; Prenosov: 0
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16.
Sarajevo Canton Winter Field Campaign 2018 : particulate air pollution in a global hotspot
Katja Džepina, Vaios Moschos, Anna Tobler, Francesco Canonaco, Deepika Bhattu, Roberto Casotto, Athanasia Vlachou, Jasna Huremović, Sabina Žero, Griša Močnik, 2020, objavljeni povzetek znanstvenega prispevka na konferenci

Opis: Nowadays, urban centres in countries of the Western Balkan region (including Bosnia and Herzegovina (B&H)) are experiencing some of the poorest European and global air quality due to the extensive use of solid fuels (e.g., wood, coal) and old vehicle fleet. Western Balkan countries lack state-of-the-art atmospheric sciences research despite high levels of ambient pollution, which makes the efforts to understand the mechanisms of their air pollution imperative. The city of Sarajevo, the capital of B&H, is situated in a basin surrounded by mountains. Particularly during the winter months, topography and meteorology cause significant pollution episodes. The Sarajevo Canton Winter Field Campaign 2018 (SAFICA) took place from Dec 04, 2017 to Mar 15, 2018 with on-line aerosol measurements and collection of daily, continuous filter PM10 samples for off-line laboratory analyses. SAFICA aimed to give the first detailed characterization of the Western Balkans aerosol composition including organic aerosol (OA) to elucidate aerosol emission sources and atmospheric processing and to estimate the adverse health effects. PM10 samples (ntotal=180) were collected at four sites in the Sarajevo Canton: a) Bjelave and b) Pofalići (urban background); c) Otoka (urban); d) Ivan Sedlo (remote). The urban sites were distributed along the city basin to study the pollutants’ urban evolution and the remote site was chosen to compare urban to background air masses. SAFICA PM10 samples underwent different off-line laboratory chemical analyses: 1) Bulk chemical composition of the total filter-collected water-soluble inorganic and OA by a high-resolution Aerodyne Aerosol Mass Spectrometer (AMS). The measured AMS OA spectra were further analysed by Positive Matrix Factorization (PMF) using the graphical user interface SoFi (Source Finder) to separate OA into subtypes characteristic for OA sources and atmospheric processes. 2) Organic and elemental carbon (OC/EC), water-soluble organic carbon, polycyclic aromatic hydrocarbons, levoglucosan, and 14C content of total carbon to evaluate OA chemical composition. 3) Major inorganic anions and cations to evaluate aerosol inorganic species. 4) Metal content in aerosol determined by two analytical techniques (AAS and ICP-MS). SAFICA on-line measurements of black carbon (Aethalometer) and the particle number concentration (Condensation Particle Counter and Optical Particle Sizer) enabled the insights into the daily evolution of primary pollutants and an assessment of aerosol size and number distribution. The combined SAFICA results for on- and off-line measurements will be presented. Our results show that the carbon-containing species make ~2/3 of PM10 mass and the majority are oxygenated, water-soluble OA species with an average OM/OC = 1.9 (Fig.1). Urban air pollution crises in the Western Balkan will be put in the context of local, regional and global air quality. Finally, we will present the scientific questions opened by SAFICA, including the advantages and limitations of SAFICA data set, and give the recommendations for future studies.
Ključne besede: Sarajevo, urban air pollution, PM10, PM2.5
Objavljeno v RUNG: 26.05.2021; Ogledov: 2442; Prenosov: 20
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17.
Long-term ozone data analysis
Vjera Butković, Tomislav Cvitaš, Katja Džepina, Nenad Kezele, Leo Klasinc, 2002, izvirni znanstveni članek

Opis: Various approaches to the analysis of 10-year continuous ozone monitoring from the EUROTRAC-TOR network station Puntijarka near Zagreb are reported. The site has a rural character (45.90degrees N; 15.97degrees E, 980 m a.s.l.) and is representative of the lower troposphere of a wider region. Mean hourly ozone volume fractions measured from 1990-1999, autocorrelation plots for all data and for data for summer periods (May-Sep.), box and whiskers representations of diurnal variations during winter (Nov.-March) and summer periods, mean monthly values and 12-month moving averages, and the Fourier transform of the complete set of 94,248 hourly mean ozone volume fractions are discussed. The data show no increase, or possibly a slight decrease, of the ozone volume fraction toward the end of the decade.
Ključne besede: long term ozone data, fourier analysis, ozone trend analysis, Puntijarka field station
Objavljeno v RUNG: 12.04.2021; Ogledov: 1974; Prenosov: 0
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18.
Characterization of ambient aerosols in Mexico City during the MCMA-2003 campaign with aerosol mass spectrometry : results from the CENICA Supersite
Dara Salcedo, T. B. Onasch, Katja Džepina, M. R. Canagaratna, Qi Zhang, J. A. Huffman, P. F. DeCarlo, J. Jayne, P. Mortimer, D. Worsnop, 2006, izvirni znanstveni članek

Opis: An Aerodyne Aerosol Mass Spectrometer (AMS) was deployed at the CENICA Supersite, during the Mexico City Metropolitan Area field study (MCMA-2003) from 31 March-4 May 2003 to investigate particle concentrations, sources, and processes. The AMS provides real time information on mass concentration and composition of the non-refractory species in particulate matter less than 1 mu m (NR-PM1) with high time and size-resolution. In order to account for the refractory material in the aerosol, we also present estimates of Black Carbon (BC) using an aethalometer and an estimate of the aerosol soil component obtained from Proton-Induced X-ray Emission Spectrometry (PIXE) analysis of impactor substrates. Comparisons of AMS + BC + soil mass concentration with other collocated particle instruments (a LASAIR Optical Particle Counter, a PM2.5 Tapered Element Oscillating Microbalance (TEOM), and a PM2.5 DustTrak Aerosol Monitor) show that the AMS + BC + soil mass concentration is consistent with the total PM2.5 mass concentration during MCMA-2003 within the combined uncertainties. In Mexico City, the organic fraction of the estimated PM2.5 at CENICA represents, on average, 54.6% (standard deviation sigma=10%) of the mass, with the rest consisting of inorganic compounds ( mainly ammonium nitrate and sulfate/ammonium salts), BC, and soil. Inorganic compounds represent 27.5% of PM2.5 (sigma=10%); BC mass concentration is about 11% (sigma=4%); while soil represents about 6.9% (sigma=4%). Size distributions are presented for the AMS species; they show an accumulation mode that contains mainly oxygenated organic and secondary inorganic compounds. The organic size distributions also contain a small organic particle mode that is likely indicative of fresh traffic emissions; small particle modes exist for the inorganic species as well. Evidence suggests that the organic and inorganic species are not always internally mixed, especially in the small modes. The aerosol seems to be neutralized most of the time; however, there were some periods when there was not enough ammonium to completely neutralize the nitrate, chloride and sulfate present. The diurnal cycle and size distributions of nitrate suggest local photochemical production. On the other hand, sulfate appears to be produced on a regional scale. There are indications of new particle formation and growth events when concentrations of SO2 were high. Although the sources of chloride are not clear, this species seems to condense as ammonium chloride early in the morning and to evaporate as the temperature increases and RH decreases. The total and speciated mass concentrations and diurnal cycles measured during MCMA-2003 are similar to measurements during a previous field campaign at a nearby location.
Ključne besede: aerosol mass-spectrometer, atmospheric aerosol, atmospheric chemistry, atmospheric physics
Objavljeno v RUNG: 12.04.2021; Ogledov: 2083; Prenosov: 0
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19.
Sources and transformations of particle-bound polycyclic aromatic hydrocarbons in Mexico City
L. C. Marr, Katja Džepina, Jose L. Jimenez, F. Reisen, H. L. Bethel, Janet Arey, J. S. Gaffney, N. A. Marley, Luisa T. Molina, Mario J. Molina, 2006, izvirni znanstveni članek

Opis: Understanding sources, concentrations, and transformations of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere is important because of their potent mutagenicity and carcinogenicity. The measurement of particle-bound PAHs by three different methods during the Mexico City Metropolitan Area field campaign in April 2003 presents a unique opportunity for characterization of these compounds and intercomparison of the methods. The three methods are ( 1) collection and analysis of bulk samples for time-integrated gas- and particle-phase speciation by gas chromatography/ mass spectrometry; ( 2) aerosol photoionization for fast detection of PAHs on particles' surfaces; and ( 3) aerosol mass spectrometry for fast analysis of size and chemical composition. This research represents the first time aerosol mass spectrometry has been used to measure ambient PAH concentrations and the first time that fast, real-time methods have been used to quantify PAHs alongside traditional filter-based measurements in an extended field campaign. Speciated PAH measurements suggest that motor vehicles and garbage and wood burning are important sources in Mexico City. The diurnal concentration patterns captured by aerosol photoionization and aerosol mass spectrometry are generally consistent. Ambient concentrations of particle-phase PAHs typically peak at similar to 110 ng m(-3) during the morning rush hour and rapidly decay due to changes in source activity patterns and dilution as the boundary layer rises, although surface-bound PAH concentrations decay faster. The more rapid decrease in surface versus bulk PAH concentrations during the late morning suggests that freshly emitted combustion-related particles are quickly coated by secondary aerosol material in Mexico City's atmosphere and may also be transformed by heterogeneous reactions.
Ključne besede: aerosol mass-spectrometer, aerodynamic diameter measurements, oxygenated organic aerosols, relative rate constants
Objavljeno v RUNG: 12.04.2021; Ogledov: 2104; Prenosov: 0
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20.
Secondary organic aerosol formation from anthropogenic air pollution : rapid and higher than expected
Rainer Volkamer, Jose L. Jimenez, F. M. San Martini, Katja Džepina, Q. Zhang, Dara Salcedo, Luisa T. Molina, D. Worsnop, 2006, izvirni znanstveni članek

Opis: The atmospheric chemistry of volatile organic compounds (VOCs) in urban areas results in the formation of 'photochemical smog', including secondary organic aerosol (SOA). State-of-the-art SOA models parameterize the results of simulation chamber experiments that bracket the conditions found in the polluted urban atmosphere. Here we show that in the real urban atmosphere reactive anthropogenic VOCs (AVOCs) produce much larger amounts of SOA than these models predict, even shortly after sunrise. Contrary to current belief, a significant fraction of the excess SOA is formed from first-generation AVOC oxidation products. Global models deem AVOCs a very minor contributor to SOA compared to biogenic VOCs (BVOCs). If our results are extrapolated to other urban areas, AVOCs could be responsible for additional 3 - 25 Tg yr(-1) SOA production globally, and cause up to - 0.1 W m(-2) additional top-of-the-atmosphere radiative cooling.
Ključne besede: atmospheric aerosol, atmospheric chemistry, volatile organic compounds, secondary organic aerosols
Objavljeno v RUNG: 12.04.2021; Ogledov: 2909; Prenosov: 0
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