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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.

The Danube River is an international river, one part of which flows through Serbia. The eco-chemical status of the Danube River is a constant topic of interest both at the local level, in each country through which the Danube flows, and at the international level. General interest to ensure the sustainable and equitable use of waters and freshwater resources in the Danube River Basin led to the development of a system for monitoring the river, which has produced data sets of its eco-chemical status. These have been collected over many years in Serbia; however, the present interest was focused only on the period from 1992 until 2006, i.e., a 15-year period. The process of defining trends of selected eco-chemical parameters, using linear regression analysis with a defined level of significance, and their separation from natural variability is of the highest importance for defining the changes in the water parameters. Through them, the fate and behavior of the eco-chemical parameters of the Danube in Serbia can be recognized and the prediction of their trends in the near future can be attempted. The obtained results revealed a constant improvement and acceptable trends of the eco-chemical status of the Danube River, as well as, substantial differences in the quality of the inflowing and out flowing water. Dunav je međunarodna reka koja jednim delom prolazi i kroz Srbiju. Ekohemijski status Dunava je tema koja je konstantno u žiži interesovanja kako na lokalnom (unutar država kroz koje Dunav protiče), tako i na međunarodnom nivou. Usled generalnog interesa da se obezbedi i održiva ravnomerna upotreba vode i slatkovodnih resursa u basenu reke Dunav, razvijen je rečni monitoring sistem koji je grupe podataka o ekohemijskom statusu Dunava na prostoru Srbije prikupljao tokom više godina. Ovaj rad je fokusiran na petnaestogodišnji period, od 1992. do 2006. godine. Utvrđivanje postojanja trendova korišćenjem linearne regresije, uz tačno određen nivo značaja vrednosti odabranih ekohemijskih parametara kao i utvrđivanja razlike u odnosu na prirodnu varijabilnost parametara, bilo je od velikog značaja za određivanje promene rečnih parametara. Pomoću njih, pokušano je određivanje sudbine i ponašanja ekohemijskih parametara Dunava na teritoriji Srbije i predviđanje njihove vrednosti u budućnosti. Dobijeni rezultati otkrili su konstantno popravljanje i prihvatljive trendove promena ekohemijskog statusa Dunava kao i primetne razlike kvaliteta vode između ulaza u Srbiju i izlaza Dunava iz Srbije.

The Palic Lake is a shallow lake typical for the Pannonian Plain. Due inadequate water quality, it was dried out in 1971 and re-established in 1977 and since than its trophicity has been worsening. Investigation of the long-term changes in the trophic state of this lake were tracked over the total phosphorous (TP), total nitrogen (TN), chlorophyll-a and Secchi disk transparency (SDT), expressed as the Carlson trophic state index (TSI). Regarding the TSI values, the water of the Palic Lake has been constantly evolving from eutrophic to hypereutrophic. TN/TP values lt 10 indicate that nitrogen is the limiting factor for algal growth. Jezero Palić je plitko jezero tipično za Panonsku niziju. Zbog neadekvatnog kvaliteta vode isušeno je 1971. godine i sanirano do 1977. godine i od tada se njegov trofički status pogoršava. Dugoročna ispitivanja promene trofičkog statusa, koja obuhvataju analize količine ukupnog fosfora, ukupnog azota, hlorofila-a i providnosti vode preko Secchijevog diska, izražena su preko Karlsonovog indeksa trofičkog statusa. Vrednost pomenutog indeksa ukazuje da je voda jezera Palić u eutrofičnoj i hipereutrofičnoj klasi. Odnos ukupnog azota i ukupnog fosfora, koji je manji od 10 ukazuje na to da je azot limitirajući faktor za rast algi.

Honeybees are great bioindicators because they cover wide areas during their foraging activity. Our study included industrial, urban and rural region, where samples were taken in July and September. Industrial region with three apiaries in the area covered two thermal power plants, Kostolac A and B. Two apiaries covered a wide urban region of Belgrade, and the rural region consisting of mainly agricultural-woodland area near village MesiA double dagger was covered with one apiary. Aim of this study was to investigate the capability of bees as bioindicators to detect different concentrations of metals in foraging regions, during two sampling periods, and to compare concentrations of Al, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Na, Ni, Pb, Sr and Zn found in their bodies. Significant differences were detected for Al, Ba, Cr, Cu, Fe, Li, and Ni between at least two analyzed regions. Significant differences in concentrations between sampling dates were found for Al, Ba, Co, Cr and Fe in at least one of the locations. For Cd, Mn, Na, Pb, Sr and Zn, no significant differences were found between locations or sampling dates, suggesting equal and stable levels of concentration for these elements in the environment. Free full text: [http://www.bioline.org.br/pdf?st16037]

Goal, Scope and Background. The objective of this paper is to determine and compare the concentrations of U and Th in soft to hard brown (lignite to sub-bituminous) coals of Serbia and Montenegro. It also presents comparison of the obtained data on U and Th concentrations with the published data on coals located in some other countries of the world. Almost the whole coal production of Serbia and Montenegro is used as feed coals for combustion in thermal power plants. Methods. Channel samples from open pit and underground mines and core samples were collected for hard and soft brown coals. For the analysis the samples were decomposed using microwave technique. Obtained solutions containing U and Th were analyzed by inductively coupled plasma mass spectroscopy (ICP-MS) using NIST standards. Results. Concentration of U from the investigated basins and the corresponding mine fields ranges within 0.60-70.10 mg/kg, 0.65-3.20 mg/kg, 0.95-6.59 rng/kg, 1.20-6.05 mg/kg, 0.80-6.66 mg/kg, 0.18-89.90 mg/kg, 0.19-4.14 mg/kg, and 0.28-3.52 mg/kg for the Kostolac, Kolubara, Krepoljin, Sjenica, Soko Banja, Bogovina East field, Senje-Resavica and Pljevlja basins, respectively. Concentration of Th ranges within 0.20-2.60 mg/kg, 0.846.57 mg/kg, 1.48-6.48 mg/kg, 0.12-2.71 mg/kg, 0.13-4.95 mg/kg, 0.14-3.48 mg/kg, 0.29-3.56 mg/kg, and 0.17-1.89 mg/kg for the Kostolac, Kolubara, Krepoljin, Sjenica, Soko Banja, Bogovina East field, Senje-Resavica and Pljevlja basins, respectively. Discussion. Brown coal from Senje-Resavica, Kolubara, Kostolac and Pljevlja ischaracterized by low U concentration. Coals form the Krepoljin, Soko Banja and Sjenica basins have slightly higher U concentrations than the mentioned group. The highest concentration of U is characteristic for the coal from the Bogovina East field. Concentration of Th in coals from Serbia and Montenegro has proved to be low. Out of all investigated coal basins, only the coal from the Krepoljin and Kolubara basins has high concentration of Th. The hydrothermally altered rocks of the Timok dacite-andesite complex, representing the basement of the Bogovina basin, could be a potential source of U, especially at the bottom part of the Lower seam of the Bogovina East field. Conclusions. This study shows that brown coals in Serbia and Montenegro (soft to hard brown coals or lignite to sub-bituminous) contain low levels of U (5.30 mg/kg, average value and 2.10 mg/kg geometric mean value) and Th (1.80 mg/kg, average value and 1.12 mg/kg geometric mean value). There are some obvious differences in concentration of U and Th in coals from different basins in Serbia and Montenegro. The approximate value for U and Th release mainly from power plants was 644.33 t and 983.46 t, respectively within the period 1965-2000 for the studied mines in Serbia, and 23.76 t and 15.05 t for the Potrlica mine (Montenegro) within the period 1965-1997. Recommendations. The coals in Serbia and Montenegro show no identifiable unfavourable impact on the surrounding environment, due to low natural radioactive concentration of U and Th, but further investigations concerning human health should be performed. Perspectives. Preliminary research revealed that in some Serbian coals (and, particularly, parts of the coal seam) U and Th content are rather high. Such coals should be carefully studied, as well as U and Th concentrations in ash, fly ash, waste disposals, nearby soil and ground water. Further studies should include determination of the radioactivity of all these products, and estimation of possible health impact. Free full text: [http://dx.doi.org/10.1065/espr2006.08.332]

In this paper the so-called independent parameter (IP) fitting method within the standard representation (SR) is explained to the case of a nonlinear model. It is shown that the SRIP-method applied to a non-linear model, converges steadily, if the model is properly chosen and thus, it can be used as a measure of the correctness of the model. This is accomplished by assuming the existence of at least one peak-described by a Gaussian formula-while the SRIP-method is applied in the iterative procedure until convergence is attained. While observing the residuals, the next peak is added to the previous model and the procedure continues. The results are illustrated by examples of oxygen soft X-ray emission spectra deconvolution for periclase, korund, and quartz.