71. Neznanka, ki na odgovor še čaka2021, intervju Opis: Vprašanje, kako in kje nastajajo kozmični delci ekstremnih energij, je odprto že več kot petdeset let. Med najverjetnejšimi kraji njihovega nastanka sodijo aktivna galaktična jedra; to so središča galaksij, v katerih se skrivajo črne luknje, ki požirajo snov iz okolice. V raziskavah mednarodne kolaboracije Pierre Auger sodelujejo tudi slovenski raziskovalci z Univerze v Novi Gorici in Instituta Jožef Stefan.
Ključne besede: kozmični delci ekstremnih energij, aktivna galaktična jedra, observatorij Pierre Auger, observatorij Cherenkov Telescope Array, CTA
Objavljeno v RUNG: 02.06.2021; Ogledov: 2395; Prenosov: 0
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73. Analiza utjecaja zagađenja zraka na zdravlje ljudi u Bosni i Hercegovini : predavanje na 2. Studentskom kongresu okolišnog zdravlja s medjunarodnim sudjelovanjem, Rijeka, Hrvatska, 6. 6. 2018Katja Džepina, 2018, prispevek na konferenci brez natisa Ključne besede: PM2.5, Ozone, Sarajevo, Tuzla, Zenica, Bosnia and Herzegovina, US EPA BenMAP, Cost-Benefit Analysis, Adverse health effects
Objavljeno v RUNG: 29.05.2021; Ogledov: 2211; Prenosov: 0
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75. Utjecaj atmosferskih lebdećih čestica na ljudsko zdravljeKatja 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: 2294; Prenosov: 0
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76. 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: 2280; Prenosov: 0
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77. Molekularna karakterizacija lebdećih čestica slobodne troposfere sa Opservatorija Pico planineKatja 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: 2631; Prenosov: 0
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78. Sarajevo Canton Winter Field Campaign 2018 : particulate air pollution in a global hotspotKatja 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: 2511; Prenosov: 20
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79. Opazovanja plimskih raztrganj zvezd z Velikim sinoptičnim pregledovalnim teleskopomKatja Bricman, Andreja Gomboc, 2018, objavljeni povzetek znanstvenega prispevka na konferenci Opis: Plimska raztrganja zvezd so redki dogodki, do katerih pride, ko zvezdo zanese v bližino masivne črne luknje v središču galaksije, kjer jo močne plimske sile črne luknje raztrgajo. Blišč svetlobe, ki ob tem nastane, lahko opazujemo do kozmoloških razdalj. Veliki sinoptični pregledovalni teleskop (Large Synoptic Survey Telescope - LSST), ki je v gradnji v Čilu, bo ponavljajoče opazoval 18.000 kvadratnih stopinj južnega neba v šestih optičnih filtrih do limitne magnitude 24,5 v r filtru. Omogočal bo opazovanja 20 milijard zvezd in 20 milijard galaksij, s primerjavo starih in novih posnetkov pa bo zaznal spremembe na nebu oziroma tranzientne izvore ter bo tako odlično orodje za iskanje plimskih raztrganj zvezd. Z uporabo simulacijskega orodja LSST smo simulirali opazovanja plimskih raztrganj zvezd na majhnem delu neba velikosti 20,25 kvadratnih stopinj. S pomočjo simuliranih svetlobnih krivulj smo ocenili število plimskih raztrganj zvezd, ki jih bo teleskop odkril v desetih letih delovanja.
Ključne besede: Plimska raztrganja zvezd, pregledovalni teleskopi
Objavljeno v RUNG: 10.05.2021; Ogledov: 1938; Prenosov: 0 |
80. Zofka Kveder : Slavic cultural and feminist icon of the early 20th centuryKatja Mihurko, 2021, samostojni znanstveni sestavek ali poglavje v monografski publikaciji Ključne besede: Zofka Kveder, slovenska književnost, Martha Tausk, Zdenka Haskova, Avgust Cesarec, Elvira Dolinar, Zdenka Marković, Julka Chlapec-Đorđević, Minka Govekar, Vladimir Jelovšek, Josef Svetopluk Machar
Objavljeno v RUNG: 12.04.2021; Ogledov: 1933; Prenosov: 57
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