Primena kontinualne "off-line" pirolize za detekciju degradacionih proizvoda poli(vinilkaprolaktama)

U ovom radu su izvedeni eksperimenti u cilju optimizacije uslova za detekciju degradacionih proizvoda poli(vinilkaprolaktama), primenom kontinualne „off-line“ pirolize u sprezi sa gasnom hromatografijom i masenom spektrometrijom (Py-GC-MS). Cilj rada je bio detekcija i identifikacija najvažnijih proizvoda pirolize, kao i kvantitativno određivanje ovog polimera na osnovu dobijenih degradacionih proizvoda

Free radical scavenging and antibacterial activities of southern Serbian red wines

Free radical scavenging and antibacterial activities were determined for several red wines from different grape varieties from the southern Serbia wine region. The amount of polyphenols and anthocyanins in selected wines was investigated and the potential antibacterial activity of the wines against pathogenic strains of Staphylococcus aureus and Escherichia coli was also determined. The free radical scavenging and antibacterial activity of the wines was correlated with polyphenolic and anthocyanin content. The significant differences in the antioxidant and antibacterial activities between the wines from grape cultivars (Cobernet Sauvingon and Pinot Noir) and the indigenous varieties (Vranac and Prokupac) were not confirmed. The hypothesis of a protective effect of red wine is supported by our results that show that the red wines with higher amounts of polyphenols and anthocyanins had higher antioxidant and antibacterial properties. (C) 2009 Published by Elsevier Ltd

The electronic structure and vibrational frequencies of the stable C84 isomer of D2 symmetry: theory and experiment

The validity of semi-empirical and DFT theoretical calculations in predicting the general pattern of IR absorption and vibrational frequencies, as well as the molecular structure of the C84 isomer of D2 symmetry is confirmed, based on recent experimental results. An excellent correlation was found between the previously reported theoretical data and the recently obtained experimental results for this molecule over the relevant spectral range for the identification of fullerenes. These results indicate that there is no error in the calculations in the significant infrared region, an assumption that was based on a previous comparison with partial experimental results

Steranes and triterpanes as a tool for identification of petroleum-type pollutants in alluvial ground waters (Danube alluvial sediments, Yugoslavia)

In this paper, ground waters from the alluvial Formation of the Danube River were investigated (samples Were taken from boreholes within the Pancevo Oil Refinery, Northern Serbia). The organic substances were extracted, their bulk composition determined, and n-alkanes were analysed in the alkane fractions, as well as the isoprenoid aliphatic alkanes, pristane and phytane (by GC analysis), and the polycyclic alkanes of the sterane and triterpane types (GC-MS analysis). The obtained results have shown that, in case that n-alkanes, pristane and phytane cannot be used (e.g. if their biodegradation has occurred in ground waters), steranes and triterpanes may serve as most useful tools in identifying oil-type pollution

Steranes and triterpanes as a tool for identification of petroleum-type pollutants in alluvial ground waters (Danube alluvial sediments, Yugoslavia)

In this paper, ground waters from the alluvial Formation of the Danube River were investigated (samples Were taken from boreholes within the Pancevo Oil Refinery, Northern Serbia). The organic substances were extracted, their bulk composition determined, and n-alkanes were analysed in the alkane fractions, as well as the isoprenoid aliphatic alkanes, pristane and phytane (by GC analysis), and the polycyclic alkanes of the sterane and triterpane types (GC-MS analysis). The obtained results have shown that, in case that n-alkanes, pristane and phytane cannot be used (e.g. if their biodegradation has occurred in ground waters), steranes and triterpanes may serve as most useful tools in identifying oil-type pollution

Development of a procedure for bioremediation treatment of underground waters and soils polluted by petroleum

Crude oil as a raw material, and all its refined products that are used as fuel, is a highly complex mixture of a large number of saturated and aromatic hydrocarbons and various nitrogen, sulphur and oxygen compounds (NSO compounds). On the other hand, there are some new inorganic and organic compounds formed during the usage of the refined products. It can be easily concluded that they are very serious environmental pollutants. The man has a duty and responsibility to clean the contaminated segments of the environment by petroleum and return them to the form in which they were before pollution. In this sense, remediation procedures are undertaken. Microbial bioremediation procedure (i.e. bioremediation), is justifiably considered the most efficient remediation procedure. This paper will present research aimed at optimizing the conditions for bioremediation of various segments of the environment (in the first place of underground waters and soils) contaminated with oil-Type pollutants. This research covers a ten-year long pathway starting from the laboratory experiments, through ex situ processes, then in situ conditions and finally to practical application. © 2018 International Social Science CouncilISSC. All rights reserved