Nivo policikličnih aromatičnih ugljovodonika u gasnoj i čestičnoj fazi u školama na različitim lokacijama u Srbiji

This study investigated seasonal variation of PAHs and their partition between gas and particulate-bounded phases in indoor and outdoor air in 4 schools In Serbia located at different locations. The sampling campaigns were conducted during one workweek at each school successively. Campaigns were conducted in schools during heating and non-heating seasons in December 2011 and June 2012. Seasonal variations of gas and particle-bounded PAHs concentrations were observed with higher levels during heating season. The highest total PAH values were associated with the gas phase in both sampling periods. The total PAHs concentration at indoor and at the outdoor sites, during heating season, ranged from 88.45 to 447.72 ng/m(3) and 201.69 to 1017.15 ng/m(3), respectively. During non-heating season, the total PAHs concentration ranged from 36.91 to 271.57 ng/m(3) in Indoor environment and 27.00 to 132.32 ng/m(3) in outdoor environment. Most of the I/O ratios were less than 1, which indicated that the indoor PAHs were mostly from outdoor sources. The use of diagnostic ratio showed that traffic emission and coal combustion are the major sources of PAHs. Only the diagnostic ratios for the school located near the industrial area showed significant deviation compared to other schools.U ovom radu su istraživane sezonske promene PAH i njihova raspodela, u gasnoj fazi i respirabilnim česticama u vazduhu unutrašnjeg prostora i spoljašnje sredine u 4 škole u Srbiji koje se nalaze na različitim lokacijama. Kampanja uzorkovanja je sprovedena tokom jedne radne nedelje u toku grejnog i negrejnog perioda (od decembra 2011. do juna 2012.) u svakoj školi. Uočene su sezonske promene nivoa PAH u gasnoj fazi i česticama, sa višim koncentracijama tokom grejnog perioda. Izmerena je veća vrednost zbira ukupnih PAH tokom oba perioda u gasnoj fazi nego PAH u česticama. Ukupna koncentracija PAH tokom grejnog perioda u unutrašnjem prostoru se kretala u opsegu od 88,45 do 447,72 ng/m3, a u spoljašnjoj sredini od 201,69 do 1017,15 ng/m3. Tokom negrejnog perioda, ukupna koncentracija PAH-ova je bila 36,91-271,57 ng/m3 u unutrašnjem prostoru, dok je u spoljašnjoj sredini bila 27,00-132,32 ng/m3. Većina I/O odnosa je bila manja od 1, što ukazuje da PAH u unutrašnjem prostoru uglavnom potiču iz spoljašnjeg vazduha. Na osnovu dijagnostičkih odnosa zaključeno je da su saobraćaj i sagorevanje uglja glavni izvori PAH. Jedino dijagnostički odnosi za školu koja se nalazi u blizini industrijske zone pokazuju značajno odstupanje u poređenju sa drugim školama

Koncentracija suspendovanih čestica (PM10 I PM2.5) i njihov odnos unutra/spolja u odabranim obrazovnim ustanovama u Nišu

Mass concentrations of particulate matter (PM) fractions were measured in educational buildings in the city of Nis, Serbia. Two sampling campaigns were conducted in winter periods. The first campaign was in the period from 21 February to 15 April 2010 at the Faculty of Occupational Safety (FOS) and the second campaign was from 20 March to 4 April 2013 at the primary school Void Karadorde (VK). PM measurements were carried out with low volume samplers Sven/Leckel LVS3. The average daily PM10 concentration inside the FOS (47.0 +/- 21.8 mu g/m(3)) was lower than PM10 concentration in outdoor air (50.7 +/- 28.1 mu g/m(3)). The average daily PM10 concentration inside the VK (54.6 +/- 17.6 mu g/m(3)) was higher than in outdoor air (47.9 +/- 22.8 mu g/m(3)). The 24-hours, average PM10 concentrations at FOS exceeded the EU limit value (50 mu g/m(3)) during 34% of days outdoors and 39% of days indoors. The 24-hours average PM10 concentrations at VK exceeded the limit value during 35% of days outdoors and 53% of days indoors. The 24-hours average PM2.5 concentrations at VK exceeded the WHO daily mean guideline value (25 mu g/m(3)) during 71% of days outdoors and 88% of days indoors. The average PM10 I/O ratio at VK was 1.57 during teaching hours, and 1.00 during no teaching hours. Similarly, average PM2.5 I/O ratio at VK was 1.11 during teaching hours and 0.90 during no teaching hours. Average daily PM2.5/PM10 ratio in the ambient air at VK was 0.87 and 0.82 at FOS. Very strong correlations between the indoor and outdoor PM concentrations were observed at VK during no teaching hours (r gt 0.8). Moderate to strong negative correlations were found between the wind speed and PM at both schools. High outdoor PM concentrations and resuspension of particles are possible reasons for the elevated indoor PM concentrations found in the study.U radu su prikazani rezultati merenja suspendovanih čestica frakcija PM10 i PM2.5 u dve izabrane obrazovne ustanove u Nišu. Kampanje merenja sprovedene su u zimskom periodu. Prva u periodu od 21.02. do 15.04.2010. na Fakultetu zaštite na radu (FOS), a druga u periodu od 20.03. do 04.04.2013. u osnovnoj školi Vožd Karađorđe (VK). Uzorkovanje suspendovanih čestica vršeno je uzorkivačima Sven/Leckel LVS3, simultano, unutar i izvan odabranih ustanova. Prosečna dnevna koncentracija čestica PM10 unutar objekta FOS (47,0±21,8 μg/m3) bila je niža u odnosu na prosečnu dnevnu koncentraciju PM10 u ambijentalnom vazduhu (50,7±28,1 μg/m3). Prosečna dnevna koncentracija čestica PM10 unutar objekta VK (54.6±17.6 μg/m3) bila je viša u odnosu na prosečnu dnevnu koncentraciju PM10 u ambijentalnom vazduhu (47.9±22.8 μg/m3). Srednje dnevne koncentracije čestica PM10 izmerene na lokaciji FOS u ambijentalnom vazduhu prelazile su dnevnu graničnu vrednost (50 ìg/m3) tokom 34% dana trajanja kampanje merenja. Srednje dnevne koncentracije čestica PM10 izmerene unutar objekta FOS prelazile su dnevnu graničnu vrednost tokom 39% dana trajanja kampanje merenja. Srednje dnevne koncentracije čestica PM10 izmerene na lokaciji VK u ambijentalnom vazduhu prelazile su dnevnu graničnu vrednost tokom 35% dana trajanja kampanje merenja, odnosno tokom 53% dana trajanja kampanje u unutrašnjosti objekta VK. Srednje dnevne koncentracije čestica PM2,5 izmerene na lokaciji VK u ambijentalnom vazduhu prelazile su dnevnu graničnu vrednost (25 ìg/m3) tokom 71% dana trajanja kampanje, odnosno tokom 88% dana u unutrašnjosti objekta VK. Prosečan dnevni odnos unutra/spolja čestica frakcije PM10 na lokaciji VK iznosio je 1,57 u vreme nastave, odnosno 1,00 kada nije bilo nastave. Prosečan dnevni odnos unutra/spolja čestica frakcije PM2,5 na lokaciji VK iznosio je 1.11 u vreme nastave, odnosno 0.90 kada nije bilo nastave. Prosečan dnevni odnos PM2,5/PM10 u ambijentalnom vazduhu na lokaciji VK bio je 0,87, odnosno 0,82 na lokaciji FOS. Detektovana je veoma jaka korelacija između koncentracija suspendovanih čestica unutar i izvan objekta VK u periodu kada nije bilo nastave (r gt 0.8). Umerena do jaka korelacija detektovana je između brzine vetra i koncentracija suspendovanih čestica na obe lokacije (FOS i VK). Visoke koncentracije suspendovanih čestica u ambijentalnom vazduhu i resuspenzija čestica najverovatniji su razlog koji utiče na povećane koncentracije suspendovanih čestica u unutrašnjem prostoru posmatranih obrazovnih ustanova

Indicative Levels of Pm in the Ambient Air in the Surrounding Villages of the Copper Smelter Complex Bor, Serbia

While information on air pollution in the form of particulate matter (PM) has been monitored for a longer period for EU countries, availability of PM data sets in the Western Balkan countries, including the Republic of Serbia, are still limited. Studies related to particulate pollution research have only been carried out in the past several years. The main objective of this paper is to present PM levels measured in the ambient air in the surrounding settlements of the Copper Smelter Complex Bor, as well as a comparison of PM levels in the surrounding settlements with those measured in Bor town. The ambient levels of PM particles (PM10, PM2.5) were measured by automatic PM monitors in 4 nearby settlements: Slatina, Ostrelj, Krivelj and Brezonik in the time interval from 2005 to 2010. According to the measurement results, PM10 and PM2.5 levels in the ambient air were higher in the cold, heating, (October-March) than In the warm no heating period (April-September). Exceeding of the daily limit of PM10 and PM2.5 mass concentration levels was observed at all measuring points. A higher number of exceedances was detected in the cold period. The results indicate that there is a significant seasonal change in the level of fine particles at all measuring places in surroundings. In addition, the PM levels in Bar are more influenced by the air pollution from the Copper Smelter Complex than the settlements in the vicinity, where the PM concentrations were greatly Influenced by the presence of domestic heating in the cold period

Half a Century of Computing in Copper Mining and Metallurgy Industry in Serbia

The Copper Mining and Smelting Complex Bor (RTB Bor) in the Republic of Serbia has a long history of computer control and computer-aided data processing. Working within the confines of the Cold War era, RTB implemented and developed four generations of computers, becoming a major influence in the IT sector and the primary computer training resource in the region

Calibration System for Thermocouple Testing

One of activities of the Mining and Metallurgy Institute is production of thermocouple elements made of precious metals. Since this is a complex technological process and the quality control of produced elements is performed by other institutions, sometimes the whole series of products can happen to be bad and not useful. This is increasing costs and time of production, as well. To prevent wasting of time and money, the special measuring system is developed. The kernel of the system is already existing microprocessor measuring station - MMS. The MMS’s hardware configuration, initially designed for industrial process control requirements with suitable input channel characteristics and adequate response time is adapted for the purpose of thermocouple calibration. Appropriate software solution is developed, as well. This article describes the practical solution for thermocouple testing and calibration. Hardware interface, principles of system integration and developed software are also included

PM and CO2 variability and relationship in the different school environments

Indoor air quality (IAQ) is very important for children health and well-being, since children are particularly vulnerable and sensitive to the presence of air pollutants. This study was performed in two naturally ventilated schools located in the same municipality. The first school is located in an urban area, at a residential-industrial site, while the other school is situated in a rural area. School buildings were chosen based on their urban environment features. The measurements were carried out in heating and non-heating periods in duration of five consecutive working days. The objective of the study was to analyze IAQ in the classrooms with special emphasis on levels and diurnal variations of particulate matter (PM10 and PM2.5), carbon dioxide (CO2) and nitrogen dioxide (NO2) in occupied and unoccupied school classrooms. In this paper, the CO2 concentrations were measured at both indoor and outdoor environments. Concentrations of CO2 higher than 1000 ppm were regularly detected in the Classrooms during teaching hours. Indoor concentrations of PM10 were not exceeded the guideline, daily average, value of 50 mu g/m(3). Concentrations of PM2.5 exceeded the guideline daily average value of 25 mu g/m(3) in both school during heating period. Concentrations of NO2 did not exceed the guideline value of 200 mu g/m(3). Ventilation rates were calculated and compared with the prescribed limits. In both occupied and unoccupied periods high correlation between CO2 and PM concentrations was determined

Comparative assessment of a real-time particle monitor against the reference gravimetric method for PM10 and PM2.5 in indoor air

Accurate monitoring of indoor mass concentrations of particulate matter is very important for health risk assessment as people in developed countries spend approximately 90% of their time indoors. The direct reading, aerosol monitoring device, Turnkey, OSIRIS Particle Monitor (Model 2315) and the European reference low volume sampler, LVS3 (Sven/Leckel LVS3) with size-selective inlets for PM10 and PM2.5 fractions were used to assess the comparability of available optical and gravimetric methods for particulate matter characterization in indoor air. Simultaneous 24-hour samples were collected in an indoor environment for 60 sampling periods in the town of Bor, Serbia. The 24-hour mean PM10 levels from the OSIRIS monitor were well correlated with the LVS3 levels (R-2=0.87) and did not show statistically significant bias. The 24-hour mean PM2.5 levels from the OSIRIS monitor were moderately correlated with the LVS3 levels (R-2=0.71), but show statistically significant bias. The results suggest that the OSIRIS monitor provides sufficiently accurate measurements for PM10. The OSIRIS monitor under-estimated the indoor PM10 concentrations by approximately 12%, relative to the reference LVS3 sampler. The accuracy of PM10 measurements could be further improved through empirical adjustment. For the fine fraction of particulate matter, PM2.5, it was found that the OSIRIS monitor underestimated indoor concentrations by approximately 63%, relative to the reference LVS3 sampler. This could lead to exposure misclassification in health effects studies relying on PM2.5 measurements collected with this instrument in indoor environments. (C) 2012 Elsevier Ltd. All rights reserved

Application of the final flotation waste for obtaining the glass-ceramic materials

This work describes the investigation of the final flotation waste (FFW), originating from the RTB Bor Company (Serbia), as the main component for the production of glass-ceramic materials. The glass-ceramics was synthesized by the sintering of FFW, mixtures of FFW with basalt (10%, 20%, and 40%), and mixtures of FFW with tuff (20% and 40%). The sintering was conducted at the different temperatures and with the different time duration in order to find the optimal composition and conditions for crystallization. The increase of temperature, from 1100 to 1480°C, and sintering time, from 4 to 6h resulted in a higher content of hematite crystal in the obtained glass-ceramic (up to 44%). The glass-ceramics sintered from pure FFW (1080°C/36h) has good mechanical properties, such as high propagation speed (4500 m/s) and hardness (10800 MPa), as well as very good thermal stability. The glass-ceramics obtained from mixtures shows weaker mechanical properties compared to that obtained from pure FFW. The mixtures of FFW with tuff have a significantly lower bulk density compared to other obtained glass-ceramics. Our results indicate that FFW can be applied as a basis for obtaining the construction materials