11. Analysis of polychlorinated biphenyls adsorbed on plastic pellets: Comparison of extraction techniquesPetra Makorič, 2017, magistrsko delo Opis: Plastic resin pellets are one of the main components of plastic fragments in the marine environment. They are small granules, generally cylinder or disk-shaped, with a diameter of a few millimetres used as industrial raw material for the production of plastic manufactured items. Resin pellets can be unintentionally released to the environment during manufacturing and transport, and can reach the ocean through processes such as surface run-off. Because of their environmental persistence, they are widely distributed in the oceans and on the beaches, all over the globe. Plastic pellets are also a sink of toxic compounds such as polychlorinated biphenyls (PCBs) that are present in the environment.
During this thesis, we designed a protocol for extracting and analysing PCBs from marine plastic resin pellets. Although pressurized fluid extraction (PFE) is not commonly used in the field of microplastics, it is a reliable and efficient technique applied in other research areas. Thus, this method was tested in this work. PCBs were extracted from plastic pellets with PFE at 65 ºC and under 100 bar with hexane. Then, the extracts were concentrated to 1 mL, cleaned up on Florisil cartridge through solid-phase extraction. Prior to analysis on GC-ECD, the cleaned extracts were concentrated again.
In the second part of the thesis, the following four extraction techniques of PCBs from plastic resin pellets were compared: Soxhlet extraction, PFE, ultrasonication and maceration. The obtain results have shown that the best efficiency and repeatability of extraction is achieved with PFE. In case of Soxhlet extraction, the results were unrepeatable. Maceration and ultrasonication had 40-45 % lower extraction efficiencies than PFE. Ključne besede: PCB, plastic resin pellets, pressurized fluid extraction, Soxhlet, maceration, ultrasonication, microplastics Objavljeno v RUNG: 22.06.2017; Ogledov: 5254; Prenosov: 268 Celotno besedilo (1,95 MB) |
12. Parallel waveform extraction algorithms for the Cherenkov Telescope Array Real-Time AnalysisAndrea Zoli, Andrej Filipčič, Gašper Kukec Mezek, Samo Stanič, Serguei Vorobiov, Lili Yang, Gabrijela Zaharijas, Danilo Zavrtanik, Marko Zavrtanik, 2015, objavljeni znanstveni prispevek na konferenci Ključne besede: Cherenkov Telescope Array (CTA), algorithms for the CTA real-time analysis, parallel waveform extraction Objavljeno v RUNG: 16.02.2017; Ogledov: 4355; Prenosov: 248 Celotno besedilo (151,69 KB) |
13. ASYMMETRIES IN SUB-EXTRACTION OUT OF NP IN SLOVENIAN : A MAGNITUDE ESTIMATION STUDYArthur Stepanov, Manca Mušič, Penka Stateva, 2016, izvirni znanstveni članek Opis: In this work, we aim to clarify the empirical paradigm that bears on two aspects of syntactic locality in Slovenian. First, building on previous work, we investigate how
robustly Slovenian observes the syntactic locality constraint precluding constituent sub-extraction out of subject noun phrases. Second, we ask whether Slovenian allows Left Branch Extraction in interrogative and non-interrogative sentences. To elucidate both issues, we conducted a magnitude estimation study, the results of which support our previous claim that there is a subject island effect in Slovenian. Furthermore,
our results suggest that Slovenian disallows Left Branch Extraction, in contrast with some other Slavic languages. We also discuss theoretical consequences of our empirical findings. Ključne besede: syntactic island, Left Branch extraction, magnitude estimation, Slovenian Objavljeno v RUNG: 03.01.2017; Ogledov: 4985; Prenosov: 251 Celotno besedilo (334,95 KB) |
14. Polyphenol, antioxidant and antimicrobial potential of six different white and red wine grape processing leftovers : /Kajetan Trošt, Anja Klančnik, Branka Mozetič Vodopivec, Melita Sternad Lemut, Katja Jug, Peter Raspor, Sonja Smole Možina, 2016, izvirni znanstveni članek Opis: BACKGROUND
During winemaking, grape polyphenols are only partly extracted, and consequently unexploited. The main aim was to characterise the phenolic content of freeze-dried grape skin and seed (FDSS) extracts obtained from Slovenian and international grape varieties and evaluate their antioxidant, antimicrobial, and anti-adhesive activities.
RESULTS
FDSS of six Vitis vinifera L. grapevine cultivars from Vipava Valley region (Slovenia) underwent extraction and sonification under different conditions. Flavonols were the predominant content of extracts from white ‘Zelen’ and ‘Sauvignon Blanc’ grape varieties, with strong antimicrobial activities against Gram-negative bacteria. ‘Pinot Noir’ FDSS extracted with 50% aqueous ethanol extraction produced a high phenolic content in the final extract, which was further associated with strong antioxidant and antimicrobial activities against all tested bacteria. Bacterial adhesion to stainless steel surfaces with minimal and maximal surface roughness was significantly inhibited (up to 60%) across a wide FDSS concentration range, with lower concentrations also effective with two types of stainless steel surfaces.
CONCLUSION
FDSS extracts from winery by-products show interesting phenolic profiles that include flavonols, catechins, anthocyanins, and hydroxycinnamic acids, with yields influenced by grapevine cultivar and extraction conditions. The antioxidant, antimicrobial and anti-adhesive activities of 50% aqueous ethanol ‘Pinot Noir’ FDSS extract reveals potential applications in food, pharmaceutical and cosmetic industries for these bioactive residues. Ključne besede: grape skins and seeds, extraction solvents, phenolic profile, antioxidant activity, antimicrobial activity, anti-adhesion activity to stainless steel Objavljeno v RUNG: 08.08.2016; Ogledov: 5296; Prenosov: 0 Gradivo ima več datotek! Več... |
15. |
16. The impact of gravel extraction on hyporheic ecology: a case study of the Bača river (W Slovenia) : dissertationNataša Mori, 2008, doktorska disertacija Ključne besede: hyporheic invertebrate, Soča river, Bača river, hyporheic biota, benthic organisms, particulate organic matter, POM, fine sediment, ETS activity, electron transport system, sediments, Nematoda, Harpacticoida, Chironomidae, gravel extraction, environmental impact assessment Objavljeno v RUNG: 19.02.2015; Ogledov: 5566; Prenosov: 392 Celotno besedilo (1,14 MB) Gradivo ima več datotek! Več... |
17. Amélioration de l´extraction des composés phénoliques du Merlot par champ électrique pulséCristèle Delsart, C. Cholet, Rémy Ghidossi, Christian Poupot, Nabil Grimi, Eugène Vorobiev, V. Milisic, Martine Mietton-Peuchot, 2012, drugi znanstveni članki Ključne besede: polyphenols, pulsed electric fields, wine, extraction, distribution Objavljeno v RUNG: 22.01.2015; Ogledov: 5539; Prenosov: 34 Povezava na celotno besedilo |
18. Effect of pulsed electric field on grape polyphenols extractionCristèle Delsart, C. Cholet, Rémy Ghidossi, Christian Poupot, Nabil Grimi, Eugène Vorobiev, V. Milisic, Martine Mietton-Peuchot, 2010, objavljeni povzetek znanstvenega prispevka na konferenci Ključne besede: pulsed electric field, red wine, extraction, polyphenols Objavljeno v RUNG: 22.01.2015; Ogledov: 5421; Prenosov: 31 Povezava na celotno besedilo |
19. |