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Organic pollutants in indoor air
No full textU ovom radu naglasak je bio na analizi onečišćenja zraka u zatvorenim prostorima. Onečišćujuće tvari u zatvorenim prostorima mogu potjecati od uobičajenih predmeta koji se nalaze u kućanstvima, kao što su namještaj, tepih, sredstva za čišćenje, uređaji za kuhanje i drugi. Onečišćenje unutrašnjeg zraka može biti puno izraženije od onečišćenja vanjskog zraka. Dozvoljene koncentracije onečišćujućih tvari vanjskog zraka propisane su zakonima i direktivama, međutim kvaliteta unutrašnjeg zraka nije regulirana. U ovom radu određene su koncentracije PM1 frakcije lebdećih čestica (čestice aerodinamičkog promjera 1 μm ili manje) te sadržaj policikličkih aromatskih ugljikovodika (PAH) u PM1 frakciji. Uzorkovanje je provedeno u kućanstvima na području Zagreba i okolice. Za čestice PM1 Direktivom o kvaliteti zraka i čišćem zraku za Europu (EU, 2008) nisu propisane granične vrijednosti, iako mogu biti opasnije po ljudsko zdravlje od čestica PM2,5 i PM10 jer se mogu lakše distribuirati po tijelu zbog svojih dimenzija. Najviša masena koncentracija PM1 frakcija čestica, kao i najviša masena koncentracija svih PAH-ova izmjerena je u uzorku uzorkovanom u kućanstvu na području naselja Trstenik. Osim Trstenika povećana koncentracija PM1 i PAH-ova izmjerena je u kućanstvu u Sigetu i Jarunu. Uočene su značajne prostorne razlike što ukazuje na nužnost daljnjih istraživanja koje će uzeti u obzir brojne čimbenike kao što su kvaliteta vanjskog zraka, fizičke karakteristike kućanstva i same navike ukućana. Dominantni PAH-ovi na gotovo svim mjernim mjestima su benzo[b]fluoranten (BbF), benzo[a]piren (BaP), benzo[ghi]perilen (BghiP) i indeno[1,2,3-cd]piren (IP). Na temelju specifičnih omjera pojedinačnih PAH-ova izvedeni su zaključci o potencijalnim izvorima onečišćenja (fosilna goriva, sagorijevanje ugljena). Utvrđen je veći doprinos PAH-ova s većim brojem prstenova u odnosu PAH-ove s 2 ili 3 prstena. Izračunati mutageni ekvivalent za detektirane PAH-ove u uzorcima iznosio je 0,439 ng/m^3, dok je karcinogeni ekvivalent iznosio 0,313 ng/m^3. Dobiveni rezultati potvrdili su prikladnost BaP-a kao markera mutagenog i kancerogenog potencijala različitih PAH-ova u zraku. Razine za dobivene ekvivalente su bile niske, stoga nisu ukazivale na lošu kvalitetu unutarnjeg zraka s obzirom na PAH-ove.The focus of this work was on the analysis of indoor air pollution. Indoor pollutants can come from typical household items such as furniture, carpets, cleaning products, cooking appliances and much more. Indoor air pollution can be much worse than outdoor air. While the concentrations of pollutants in outdoor air are regulated by laws and directives, there are no regulations for indoor air quality. The concentrations of the PM1 fraction (particles with an aerodynamic diameter of 1 μm or less) of particulate matter and the composition of polycyclic aromatic hydrocarbons (PAH) in the PM1 fraction were determined, and sampling was carried out in households in the Zagreb area and its surroundings. The Air Quality and Cleaner Air for Europe Directive (EU, 2008) does not set limit values for PM1, although they can be more dangerous to human health than PM2.5 and PM10 particles because their size makes them easier to disperse in the body. The highest mass concentration of PM1 particle fractions and the highest mass concentration of all PAHs were measured in the sample taken from a household in the Trstenik. In addition to Trstenik, elevated concentrations of PM1 and PAHs were also measured in households in Siget and Jarun. Significant spatial differences were observed, which indicates the necessity of further research that will take into account numerous factors such as the quality of the outdoor air, the physical characteristics of the household and the habits of the householders themselves. The dominant PAHs at almost all measurement sites are benzo[b]fluoranthene (BbF), benzo[a]pyrene (BaP), benzo[ghi]perylene (BghiP), and indeno[1,2,3-cd]pyrene (IP ). Based on the specific ratios of the individual PAHs, conclusions were drawn about possible sources of pollution (fossil fuels, coal combustion). A greater contribution was found from PAHs with a larger number of rings than from PAHs with 2 or 3 rings. The calculated mutagenic equivalent for the PAHs detected in the samples was 0.439 ng/m^3, while the carcinogenic equivalent was 0.313 ng/m^3.
The results obtained confirm the suitability of BaP as a marker for the mutagenic and carcinogenic potential of various PAHs in the air. The values determined for the equivalents were low and therefore not indicative of poor indoor air quality in view of PAHs
Organic pollutants in indoor air
No full textU ovom radu naglasak je bio na analizi onečišćenja zraka u zatvorenim prostorima. Onečišćujuće tvari u zatvorenim prostorima mogu potjecati od uobičajenih predmeta koji se nalaze u kućanstvima, kao što su namještaj, tepih, sredstva za čišćenje, uređaji za kuhanje i drugi. Onečišćenje unutrašnjeg zraka može biti puno izraženije od onečišćenja vanjskog zraka. Dozvoljene koncentracije onečišćujućih tvari vanjskog zraka propisane su zakonima i direktivama, međutim kvaliteta unutrašnjeg zraka nije regulirana. U ovom radu određene su koncentracije PM1 frakcije lebdećih čestica (čestice aerodinamičkog promjera 1 μm ili manje) te sadržaj policikličkih aromatskih ugljikovodika (PAH) u PM1 frakciji. Uzorkovanje je provedeno u kućanstvima na području Zagreba i okolice. Za čestice PM1 Direktivom o kvaliteti zraka i čišćem zraku za Europu (EU, 2008) nisu propisane granične vrijednosti, iako mogu biti opasnije po ljudsko zdravlje od čestica PM2,5 i PM10 jer se mogu lakše distribuirati po tijelu zbog svojih dimenzija. Najviša masena koncentracija PM1 frakcija čestica, kao i najviša masena koncentracija svih PAH-ova izmjerena je u uzorku uzorkovanom u kućanstvu na području naselja Trstenik. Osim Trstenika povećana koncentracija PM1 i PAH-ova izmjerena je u kućanstvu u Sigetu i Jarunu. Uočene su značajne prostorne razlike što ukazuje na nužnost daljnjih istraživanja koje će uzeti u obzir brojne čimbenike kao što su kvaliteta vanjskog zraka, fizičke karakteristike kućanstva i same navike ukućana. Dominantni PAH-ovi na gotovo svim mjernim mjestima su benzo[b]fluoranten (BbF), benzo[a]piren (BaP), benzo[ghi]perilen (BghiP) i indeno[1,2,3-cd]piren (IP). Na temelju specifičnih omjera pojedinačnih PAH-ova izvedeni su zaključci o potencijalnim izvorima onečišćenja (fosilna goriva, sagorijevanje ugljena). Utvrđen je veći doprinos PAH-ova s većim brojem prstenova u odnosu PAH-ove s 2 ili 3 prstena. Izračunati mutageni ekvivalent za detektirane PAH-ove u uzorcima iznosio je 0,439 ng/m^3, dok je karcinogeni ekvivalent iznosio 0,313 ng/m^3. Dobiveni rezultati potvrdili su prikladnost BaP-a kao markera mutagenog i kancerogenog potencijala različitih PAH-ova u zraku. Razine za dobivene ekvivalente su bile niske, stoga nisu ukazivale na lošu kvalitetu unutarnjeg zraka s obzirom na PAH-ove.The focus of this work was on the analysis of indoor air pollution. Indoor pollutants can come from typical household items such as furniture, carpets, cleaning products, cooking appliances and much more. Indoor air pollution can be much worse than outdoor air. While the concentrations of pollutants in outdoor air are regulated by laws and directives, there are no regulations for indoor air quality. The concentrations of the PM1 fraction (particles with an aerodynamic diameter of 1 μm or less) of particulate matter and the composition of polycyclic aromatic hydrocarbons (PAH) in the PM1 fraction were determined, and sampling was carried out in households in the Zagreb area and its surroundings. The Air Quality and Cleaner Air for Europe Directive (EU, 2008) does not set limit values for PM1, although they can be more dangerous to human health than PM2.5 and PM10 particles because their size makes them easier to disperse in the body. The highest mass concentration of PM1 particle fractions and the highest mass concentration of all PAHs were measured in the sample taken from a household in the Trstenik. In addition to Trstenik, elevated concentrations of PM1 and PAHs were also measured in households in Siget and Jarun. Significant spatial differences were observed, which indicates the necessity of further research that will take into account numerous factors such as the quality of the outdoor air, the physical characteristics of the household and the habits of the householders themselves. The dominant PAHs at almost all measurement sites are benzo[b]fluoranthene (BbF), benzo[a]pyrene (BaP), benzo[ghi]perylene (BghiP), and indeno[1,2,3-cd]pyrene (IP ). Based on the specific ratios of the individual PAHs, conclusions were drawn about possible sources of pollution (fossil fuels, coal combustion). A greater contribution was found from PAHs with a larger number of rings than from PAHs with 2 or 3 rings. The calculated mutagenic equivalent for the PAHs detected in the samples was 0.439 ng/m^3, while the carcinogenic equivalent was 0.313 ng/m^3.
The results obtained confirm the suitability of BaP as a marker for the mutagenic and carcinogenic potential of various PAHs in the air. The values determined for the equivalents were low and therefore not indicative of poor indoor air quality in view of PAHs
Thermal radiation
No full textToplinsko zračenje je širenje topline elektromagnetskim valovima. Sve tvari s temperaturom većom od apsolutne nule u prirodi emitiraju toplinsko zračenje. Ono nastaje toplinskim gibanjem unutar tvari. Ljudi nisu ni svjesni kako se toplinsko zračenje nalazi svuda oko nas. Nekih od primjera su: zagrijavanje Zemlje pomoću Sunca; toplinska energija koju emitira radijator; svjetlosna energija koju zrače žarulje sa žarnom niti; plamenovi, ugljen i vruće cigle zrače toplinu izravno na predmete u prostoriji. Svrha ovog rada bila je dati pregled najvažnijih zakona kojima se može opisati djelovanje toplinskog zračenja, a to su Wienov zakon, Planckov zakon zračenja crnog tijela, Stefan-Boltzmannov zakon i Kirchhoffov zakon. Pojašnjeno je ponašanje navedenih zakona na idealnom crnom tijelu, ali i kod realnih sustava.Thermal radiation is the spread of heat by electromagnetic waves. All matter in nature with a temperature higher than absolute zero emits thermal radiation. It is created by thermal motion within matter. People are not even aware that thermal radiation is everywhere around us. Some examples are: the heating of the Earth by the Sun; the heat energy emitted by the radiator; the light energy emitted by incandescent bulbs; the flames, coal and hot bricks radiate heat directly to the objects in the room. The aim of this paper was to provide an overview of the most important laws that can describe the action of thermal radiation, namely Wien's law, Planck's law of blackbody radiation, Stefan-Boltzmann's law and Kirchhoff's law. The behavior of the aforementioned laws on an ideal blackbody, but also on the real systems, is clarified
Organic pollutants in indoor air
No full textU ovom radu naglasak je bio na analizi onečišćenja zraka u zatvorenim prostorima. Onečišćujuće tvari u zatvorenim prostorima mogu potjecati od uobičajenih predmeta koji se nalaze u kućanstvima, kao što su namještaj, tepih, sredstva za čišćenje, uređaji za kuhanje i drugi. Onečišćenje unutrašnjeg zraka može biti puno izraženije od onečišćenja vanjskog zraka. Dozvoljene koncentracije onečišćujućih tvari vanjskog zraka propisane su zakonima i direktivama, međutim kvaliteta unutrašnjeg zraka nije regulirana. U ovom radu određene su koncentracije PM1 frakcije lebdećih čestica (čestice aerodinamičkog promjera 1 μm ili manje) te sadržaj policikličkih aromatskih ugljikovodika (PAH) u PM1 frakciji. Uzorkovanje je provedeno u kućanstvima na području Zagreba i okolice. Za čestice PM1 Direktivom o kvaliteti zraka i čišćem zraku za Europu (EU, 2008) nisu propisane granične vrijednosti, iako mogu biti opasnije po ljudsko zdravlje od čestica PM2,5 i PM10 jer se mogu lakše distribuirati po tijelu zbog svojih dimenzija. Najviša masena koncentracija PM1 frakcija čestica, kao i najviša masena koncentracija svih PAH-ova izmjerena je u uzorku uzorkovanom u kućanstvu na području naselja Trstenik. Osim Trstenika povećana koncentracija PM1 i PAH-ova izmjerena je u kućanstvu u Sigetu i Jarunu. Uočene su značajne prostorne razlike što ukazuje na nužnost daljnjih istraživanja koje će uzeti u obzir brojne čimbenike kao što su kvaliteta vanjskog zraka, fizičke karakteristike kućanstva i same navike ukućana. Dominantni PAH-ovi na gotovo svim mjernim mjestima su benzo[b]fluoranten (BbF), benzo[a]piren (BaP), benzo[ghi]perilen (BghiP) i indeno[1,2,3-cd]piren (IP). Na temelju specifičnih omjera pojedinačnih PAH-ova izvedeni su zaključci o potencijalnim izvorima onečišćenja (fosilna goriva, sagorijevanje ugljena). Utvrđen je veći doprinos PAH-ova s većim brojem prstenova u odnosu PAH-ove s 2 ili 3 prstena. Izračunati mutageni ekvivalent za detektirane PAH-ove u uzorcima iznosio je 0,439 ng/m^3, dok je karcinogeni ekvivalent iznosio 0,313 ng/m^3. Dobiveni rezultati potvrdili su prikladnost BaP-a kao markera mutagenog i kancerogenog potencijala različitih PAH-ova u zraku. Razine za dobivene ekvivalente su bile niske, stoga nisu ukazivale na lošu kvalitetu unutarnjeg zraka s obzirom na PAH-ove.The focus of this work was on the analysis of indoor air pollution. Indoor pollutants can come from typical household items such as furniture, carpets, cleaning products, cooking appliances and much more. Indoor air pollution can be much worse than outdoor air. While the concentrations of pollutants in outdoor air are regulated by laws and directives, there are no regulations for indoor air quality. The concentrations of the PM1 fraction (particles with an aerodynamic diameter of 1 μm or less) of particulate matter and the composition of polycyclic aromatic hydrocarbons (PAH) in the PM1 fraction were determined, and sampling was carried out in households in the Zagreb area and its surroundings. The Air Quality and Cleaner Air for Europe Directive (EU, 2008) does not set limit values for PM1, although they can be more dangerous to human health than PM2.5 and PM10 particles because their size makes them easier to disperse in the body. The highest mass concentration of PM1 particle fractions and the highest mass concentration of all PAHs were measured in the sample taken from a household in the Trstenik. In addition to Trstenik, elevated concentrations of PM1 and PAHs were also measured in households in Siget and Jarun. Significant spatial differences were observed, which indicates the necessity of further research that will take into account numerous factors such as the quality of the outdoor air, the physical characteristics of the household and the habits of the householders themselves. The dominant PAHs at almost all measurement sites are benzo[b]fluoranthene (BbF), benzo[a]pyrene (BaP), benzo[ghi]perylene (BghiP), and indeno[1,2,3-cd]pyrene (IP ). Based on the specific ratios of the individual PAHs, conclusions were drawn about possible sources of pollution (fossil fuels, coal combustion). A greater contribution was found from PAHs with a larger number of rings than from PAHs with 2 or 3 rings. The calculated mutagenic equivalent for the PAHs detected in the samples was 0.439 ng/m^3, while the carcinogenic equivalent was 0.313 ng/m^3.
The results obtained confirm the suitability of BaP as a marker for the mutagenic and carcinogenic potential of various PAHs in the air. The values determined for the equivalents were low and therefore not indicative of poor indoor air quality in view of PAHs
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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