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Stanovení obsahu benzo(a)pyrénu v uzených masných výrobcích s využitím moderních izolačních technik / Determination of benzo(a)pyrene content in smoked meat products using modern isolation techniquesSuranová, Mária January 2013 (has links)
In this work a new simplified procedure for isolation and determination of PAH in smoked meat products was developed. This procedure is using ASE as selective extraction technique. Its principle is addition of silicagel activated during 18 hours at 140 °C directly to the extraction cell in ratio 10 g to 1 g of homogenized sample. In the next step the sample is extracted by n-hexane at 100 °C and 10 MPa for three 10 minutes static extraction cycles. The flush volume is 60 % and the purge time 120 sec. During the extraction silicagel adsorb koextracted lipids and thus the obtained extract is suitable for immediate HPLC-FLD analysis. On the contrary, the classical extraction procedures with nonpolar solvent require difficult purification of extract for removal of unwanted lipids. Mostly applied techniques here are GPC and SPE. The new procedure was validated for determination of B[a]P as well as for determination of 4 PAH (B[a]A, CHR, B[b]F, B[a]P) in smoked sausages. It meets all requirements to be set by Regulation (EC) No 333/2007, respective by new Regulation (EC) No 836/2011. After the method validation, the content of 4 PAH was investigated in twelve samples of various smoked sausages manufactured in Slovakia. Two analyzed products showed high PAH levels exceeding maximum legislation limits set for B[a]P as well as for sum of 4 PAH by Regulation (EC) No 835/2011.
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Karakterizacija bioremedijacionih procesa u sedimentima zagađenim policikličnim aromatičnim ugljovodonicima i procena biodostupnosti / Characterisation of bioremediation processes in sediment contaminated with polycyclic aromatic hydrocarbons and bioavailability assessmentBeljin Jelena 17 December 2015 (has links)
<p>U okviru ovog istraživanja ispitani su: 1. Optimalni uslovi za<br />eksperimente biodegradacije policikličnih aromatičnih ugljovodonika sa istim i<br />različitim brojem prstenova; 2. Uticaj struture i matriksa na biodegradaciju<br />policikličnih aromatičnih ugljovodonika sa istim brojem prstenova; 3.<br />Fitotoksičnost biljaka (testovi klijavosti i usvajanje policikličnih aromatičnih<br />ugljovodonika); 4. Procena potencijalne biodostupne frakcije primenom<br />različitih hemijskih sorbenata (HPCD, βCD i MCD, XAD4 i TenaxTA) i 5.<br />Korelacija dobijenih rezultata testovima biodegradacije, testovima klijavosti,<br />testovima fitotoksičnosti i rezultata dobijenih iz eksperimenta procene<br />biodostupnosti hemijskim testovima. Rezultati su pokazali da se optimalni<br />uslovi za biodegradaciju postižu dodatkom mineralnih medijuma, inokuluma i<br />surfaktanata. Posmatrajući uticaj sadržaja gline i organske materije i strukture<br />molekula, najveći stepen biorazgradnje ima fluoranten, što je u skladu sa<br />njegovim fizičko-hemijskim osobinama, dok se sadržaj pirena i krizena nije<br />mogao jasno korelirati sa sadržajem organske materije i gline. Što se tiče<br />testova fitotoksičnosti, sva semena su proklijala, što govori u prilog tome da<br />mešavina ovih kontaminanata pri ispitivanim koncentracijama nije inhibirala<br />klijanje biljaka. Testovi usvojivosti ispitivanih PAH-ova su pokazali da je<br />najmanji procenat usvojivosti semenom dobijen za benzo(a)piren, što se može<br />objasniti njegovom kompleksnijom strukturom. Hemijskim testovima za<br />procenu biodostupnosti je sa druge strane pokazano da se desorpcija u prisustvu<br />MCD, XAD4 smole i Tenaxa može koristiti kao jednostavna metoda za procenu<br />potencijalne biodostupne frakcije organskih jedinjenja u sistemima sediment -voda.</p> / <p>The aim of this study was to investigate: 1. The optimal conditions for the biodegradation of polycyclic aromatic hydrocarbons with the same and different numbers of rings; 2. The impact of structure and matrix biodegradation of polycyclic aromatic hydrocarbons with the same number of rings; 3. Phytotoxicity (germination tests and polycyclic aromatic hydrocarbon uptake); 4. The means for assessing the bioavailable fractions using various chemical sorbents (HPCD, βCD, MCD, XAD4 and TenaxTA) and 5. The correlation between the results of the biodegradation tests, germination tests, phytotoxicity tests and the results obtained from the experiments in the assessment of bioavailability and chemical tests. The results showed that the optimal conditions for biodegradation are achieved by the addition of mineral media, inoculum and surfactants. When considering the effect of the contents of clay and organic matter and the structure of the molecules, the highest degree of biodegradation was observed with fluoranthene, which is in line with its physico-chemical properties. The concentrations of pyrene and chrysene were not clearly correlated with the organic matter and clay contents. During thephytotoxicity tests, all seeds sprouted, which speaks in favor of a mixture of these contaminants not inhibiting the germination of the plants. Tests for the uptake of the investigated PAHs showed that the lowest percentage seed uptake was for benzo(a)pyrene, which is explained by its more complex structure. Chemical tests for evaluating bioavailability have shown that desorption in the presence of MCD, XAD4 and Tenax resins can be used as a simple method for the evaluation of a potential bioavailable fraction of organic compounds in water-sediment systems.</p>
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Uticaj različitih tehnoloških parametara na formiranje boje tradicionalne fermentisane kobasice (Petrovačka kobasica) tokom standardizacije bezbednosti i kvaliteta / The influence of different technological parameters during standardization of safety and quality on the color formation of traditional fermented sausage (Petrovačka kobasica)Škaljac Snežana 22 December 2014 (has links)
<p>Zadatak ove doktorske disertacije je bio da se utvrdi uticaj različitih tehnoloških parametara na formiranje boje Petrovačke kobasice, kao i da se modelovanjem tradicionalne tehnologije utvrdi zavisnost između brojnih tehnoloških parametara i optimalnog kvaliteta boje ovog tradicionalnog proizvoda, radi standardizacije kvaliteta i bezbednosti, a u cilju dobijanja prepoznatljivog proizvoda vrhunskog kvaliteta koji bi se kontinuirano proizvodio.<br />U cilju realizacije postavljenih zadataka tokom tri proizvodne sezone je izrađeno 13 modela Petrovačke kobasice kako bi se ispitao uticaj sledećih varijabilnih tehnoloških parametara: proizvodne sezone, vremena otkoštavanja mesa post mortem, vrste upotrebljenog omotača (prirodni i veštački), ručnog i mašinskog mešanja, dimljenja u tradicionalnim i kontrolisanim uslovima, sušenja i zrenja u tradicionalnim i kontrolisanim uslovima, dodatka izolovane autohtone starter kulture, vremena skladištenja i načina pakovanja (neupakovane, pakovane u vakuumu i modifikovanoj atmosferi) na proces formiranja boje.<br />Formiranje boje Petrovačke kobasice tokom procesa dimljenja, sušenja i skladištenja praćeno je određivanjem instrumentalnih pokazatelja boje (L*, a*, b*, h, C*, R, BI i ΔE) na površini i preseku Petrovačkih kobasica. Utvrđeni su brojni tehnološki parametri (vrednost pH, sadržaj vlage, sadržaj ukupnih masti, sadržaj ukupnog pepela i sadržaj hlorida), pokazatelji senzornog kvaliteta (spoljašnji izgled i stanje omotača, boja i održivost boje na preseku, ukupan senzorni kvalitet) i kvalitet ljute začinske paprike. Analizom rezultata dobijenih u ovim ispitivanjima zaključeno je da su kobasice izrađene od ohlađenog mesa dimljene i sušene u tradicionalnim uslovima (B1 i B2 grupe) imale optimalan kvalitet boje i bile vrhunskog (zaštićenog) senzornog kvaliteta. Niže temperature (8,30°C-10,7°C) tokom procesa dimljenja i sušenja, sporiji pad vrednosti pH, od 5,69 (nadev) do ~5,4 (na kraju procesa fermentacije) i sadržaj hlorida ~ 3% u gotovom proizvodu, uz dodatak kvalitetne ljute začinske paprike omogućili su formiranje optimalne boje ove grupe kobasica. Optimalnu boju preseka kobasica karakterišu numerički manje vrednosti instrumentalnih pokazatelja boje (L*, a*, b*, h, C* i BI) u odnosu na kobasice sa nižim senzornim ocenama za boju. Tokom skladištenja (od kraja sušenja do 270. dana proizvodnje) utvrđene su manje promene instrumentalnih pokazatelja boje na površini i preseku Petrovačkih kobasica kada su skladištene upakovane (vakuum i modifikovana atmosfera) u poređenju sa neupakovanim. Pakovanje u vakuumu i modifikovanoj atmosferi je dobro rešenje za očuvanje optimalnih karakteristika boje kobasica, jer su upakovane kobasice B1 i B2 grupe skladištene 4 meseca od završetka procesa sušenja (od 90. do 210. dana od dana proizvodnje) bez promena senzornog kvaliteta boje, a zatim su do kraja perioda skladištenja (270. dana proizvodnje) promene bile neznatne.<br />Uzimajuću u obzir da su ova istraživanja deo šire koncipitranih istraživanja razvoja tradicionalne tehnologije proizvodnje Petrovačke kobasice i standardizacije kvaliteta i bezbednosti, ispitan je uticaj varijabilnih tehnoloških parametara i na formiranje policikličnih aromatičnih ugljovodonika u Petrovačkoj kobasici, kao veoma važnih pokazatelja zdravstvene bezbednosti kobasica.<br />Jedan od najznačajnijih rezultata u ovim istraživanjima je da benzo[a]piren nije detektovan ni u jednom uzorku Petrovačke kobasice. Takođe je zaključeno da je Petrovačka kobasica dimljena na tradicionalan način, kao i u industrijskim uslovima bezbedna za potrošače sa aspekta sadržaja policikličnih aromatičnih ugljovodonika, jer su svi ispitani uzorci kobasica ispunjavali uslove propisane domaćim i evropskim propisima.</p> / <p>The aim of this Ph.D. dissertation was to determine the influence of various technological parameters on the colour formation of Petrovačka kobasica, as well as to define correlation between number of technological parameters and optimal colour quality of traditional product (by modelling traditional technology), in order to standardize quality and safety, and consequently with the main goal to obtain a recognizable high quality product that could be continuously produced throughout the whole year period.<br />To achieve the defined tasks in three production season 13 models of Petrovačka kobasica were produced in order to examine the effect of the following variable technological parameters: production season, post mortem time of meat deboning, type of the casing (natural and artificial), manual or mechanical mixing, smoking in traditional and controlled conditions, drying and ripening in traditional and controlled conditions, the addition of isolated indigenous starter culture, and storage time and packaging (unwrapped, packed in vacuum and modified atmosphere) in the process of colour formation.<br />Colour formation of Petrovačka kobasica during smoking and drying processes and storage was followed by determination of instrumental colour parameters (L*, a*, b*, h, C*, R, BI and ΔE) on the surface and cut cross section of Petrovačka kobasica. The number of technological parameters (pH, content of moisture, total fat, total ash and chloride), indicators of sensory quality (sausage appearance and condition of casing, colour and colour stability at the cut cross section, the overall sensory quality) and quality of red hot paprika powder were determined. Analysing the results obtained in these studies it was concluded that sausages produced from chilled meat and smoked in traditional conditions (sausages of B1 and B2 groups) had the optimal colour quality and superior (protected) sensory quality. Lower temperatures (8.30°C-10.7°C) during smoking and drying processes, slower decrease of pH value from 5.69 (raw sausage after stuffing) to ~ 5.4 (at the end of the fermentation process) and the chloride content ~ 3% in the final product, with the addition of high quality red hot paprika powder enable the formation of the optimal colour of these groups of sausages. Optimal colour of cut cross section of sausages was characterized with numerically smaller values of instrumental colour parameters (L*, a*, b*, h, C* and BI) in relation to sausages with lower scores for sensory evaluated colour. During storage (from the end of drying process up to 270 days of production), minor changes of instrumental colour characteristics on the surface and cut cross section of Petrovačka kobasica were noted when sausages were stored packed in vacuum or modified atmosphere, compared with unpackaged ones. Packing in vacuum and modified atmosphere is a good solution for the preservation of optimal colour characteristics, as packaged sausages of B1 and B2 groups stored for 4 months from the end of the drying process (from 90 to 210 days from the date of production) had no changes in sensory evaluated colour quality. Further, until the end of storage (270 days of production) just minor changes of this sensory parameter were noticed.<br />Considering that these investigations are a part of wider conceived researches of development of traditional technology of Petrovačka kobasica and standardization of quality and safety, the influence of variable technological parameters on the formation of polycyclic aromatic hydrocarbons in Petrovačka kobasica, as a very important indicator of health safety of sausage, were also studied.<br />One of the most important results of these researches is that benzo[a]pyrene was not detected in any sample of Petrovačka kobasica. It was also concluded that Petrovačka kobasica smoked in traditional way, as well as in industrial conditions was safe for consumers in the terms of the content of polycyclic aromatic hydrocarbons, as all samples of analysed sausages meet the requirements defined by national and European regulations.</p>
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Polycyclic heteroaromatic hydrocarbons containing a benzoisoindole coreRichter, Marcus, Schellhammer, Karl Sebastian, Machata, Peter, Cuniberti, Gianaurelio, Popov, Alexey, Ortmann, Frank, Berger, Reinhard, Müllen, Klaus, Feng, Xinliang 31 January 2020 (has links)
By the combination of 9a-azaphenalene and a perpendicularly oriented acene, we have synthesized three derivatives of a series of novel, fully-conjugated nitrogen-containing polycyclic aromatic hydrocarbons (PAHs), namely [7,8]naphtho[2′,3′:1,2]indolizino[6,5,4,3-def]phenanthridine, with an acetylene triisopropylsilyl (TIPS), phenyl or benzothiophenyl substituent. Their optoelectronic properties were studied via UV-Vis-NIR absorption, fluorescence spectroscopy and cyclic voltammetry. In addition, in situ spectroelectrochemistry was performed to investigate the optical and magnetic properties of the mono-radical cation and anion by quasi-reversible oxidation and reduction of 11-(tert-butyl)-5,17-bis((triisopropylsilyl)ethynyl)[7,8]naphtho[2′,3′:1,2]indolizino[6,5,4,3-def]phenanthridine (1a). Theoretical modelling confirmed the predominately closed-shell electronic ground state with a weak diradical character depending on the geometry.
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Biodegradace polycyklických aromatických uhlovodíků ve dřevě ošetřeném kreozotovým olejem / Biodegradation of polycyclic aromatic hydrocarbon in wood treated with creosote oilFabiánová, Tereza January 2010 (has links)
Wood contaminated by polycyclic aromatic hydrocarbons (PAH) represent a serious environmental risk. Composting seems to be an effective method for decontamination of such waste material. PAHs are degraded mainly under aerobic conditions the efficiency of composting could be strongly affected by the process conditions. This work is aimed at the comparison of PAH removal by a 340-days-long composting in laboratory scale composting pilots and a 240-days-long process in a pilot scale. To set up composting piles a "green substrate" commercially used for button-mushroom production and a grass substrate were used. The use of the grass substrate led to a higher PAHs removal (97% of the initial sum of PAHs) in comparison to the green substrate (81% of the initial sum of PAHs). Further, the effect of the size of wood particles on the PAHs removal efficiency was demonstrated. Analysis of phospholipid fatty acids showed an enhanced growth of gramm-negative bacteria and fungi during the composting processes. During the degradation process the enzyme activity of laccase was detected. The ecotoxicological test using a bioluminescent bacteria Vibrio fischeri and a seed germination test using seeds of Hordeum vulgare L. showed that probably no toxic products were formed during the PAHs degradation in these experiments.
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Formation of Polycyclic Aromatic Hydrocarbons On the Surfaces of Ultra-High Temperature Treated MeatFoote, Michelle T. 01 May 1993 (has links)
The effect of ultra-high temperature (UHT) on production of polycyclic aromatic hydrocarbons (PAHs) on the surface of beef steaks was determined. Beef steaks were treated with five treatments, raw, UHT, UHT/grill marks, UHT/grill marks/microwave, and charcoal grilled. Four PAHs, benzo[a]pyrene, benz[a]anthracene, benzo[b]fluoranthene, and benzo[k]fluoranthene, were quantified. High performance liquid chromatography (HPLC) and gas chromatography (GC) were used to purify and analyze the PAH extracts, respectively. Levels of PAH found on charcoal-grilled steaks were higher than those observed in the literature. A balanced incomplete block design was used to analyze the data. There were no significant differences among the treatments in the production of the benzofluoranthenes. There were significant increases in production of benzo[a]pyrene and benz[a]anthracene when grill marks were applied to the UHT steak. Microwaving significantly decreased the levels of benzo[a]pyrene and benz[a]anthracene. The production of these PAHs on UHT/grill mark/microwave steak did not differ significantly from the charcoal-grilled steak in the levels of PAH quantified.
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Anaerobic Degradation of Polycyclic Aromatic Hydrocarbons at a Creosote-Contaminated Superfund Site and the Significance of Increased Methane Production in an Organophilic Clay Sediment CapSmith, Kiara L. 01 January 2010 (has links)
The overall goal of this work was to investigate microbial activity leading to the anaerobic degradation of polycyclic aromatic hydrocarbons and an organophilic clay sediment cap used at a creosote-contaminated Superfund site. To determine whether or not PAHs were being degraded under anaerobic conditions in situ, groundwater and sediment porewater samples were analyzed for metabolic biomarkers, or metabolites, formed in the anaerobic degradation of naphthalene (a low-molecular weight PAH). In addition, a groundwater push-pull method was developed to evaluate whether the transformation of deuterated naphthalene to a deuterated metabolite could be monitored in situ and if conservative rates of transformation can be defined using this method. Metabolites of anaerobic naphthalene degradation were detected in all samples that also contained significant levels of naphthalene. Anaerobic degradation of naphthalene appears to be widespread in the upland contaminated aquifer, as well as within the adjacent river sediments. A zero-order rate of transformation of naphthalene-D₈ to naphthoic acid-D₇was calculated as 31 nM·d-¹. This study is the first reported use of deuterated naphthalene to provide both conclusive evidence of the in situ production of breakdown metabolites and an in situ rate of transformation. Methane ebullition was observed in areas of the sediment cap footprint associated with organophilic clay that was used a reactive capping material to sequester mobile non-aqueous phase liquid (NAPL) at the site. Anaerobic slurry incubations were constructed using sediment core samples to quantify the contribution of the native sediment and the different layers of capping material (sand and organophilic clay) to the overall methane production. Substrate addition experiments using fresh, unused organophilic clay, as well as measured changes in total carbon in organophilic clay over time supported the hypothesis that microbes can use organophilic clay as a carbon source. Quantitative PCR (qPCR) directed at the mcrA gene enumerated methanogens in field samples and incubations of native sediment and capping materials. Denaturing gradient gel electrophoresis (DGGE) was also performed on DNA extracted from these samples to identify some of the predominant microorganisms within the sediment cap footprint. The organophilic clay incubations produced up to 1500 times more methane than the native sediment and sand cap incubations. The organophilic clay field sample contained the greatest number of methanogens and the native sediment contained the least. However, the native sediment incubations had greater numbers of methanogens compared to their respective field sample and comparable numbers to the organophilic clay incubation. An increase in methane production was observed with the addition of fresh, unused organophilic clay to the already active organophilic clay incubations indicating that organophilic clay stimulates methanogenesis. In addition, organophilic clay retrieved from the field lost about 10% of its total carbon over a 300-day incubation period suggesting that some component of organophilic clay may be converted to methane. DGGE results revealed that some of the predominant groups within the native sediment and sediment cap were Bacteriodetes, Firmicutes, Chloroflexi, and Deltaproteobacteria. An organism 98% similar to Syntrophus sp. was identified in the organophilic clay suggesting this organism may be working in concert with methanogens to convert the organic component of organophilic clay ultimately to methane. The capacity of organophilic clay to sequester organic contaminants will likely change over time as the organic component is removed from the clay. This, in turn, affects the use of this material as a long-term remedial strategy in reduced, contaminated environments.
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Model of PAH and PCB bioaccumulation in Mya arenaria and application for site assessment in conjunction with sediment quality screening criteria / Model of polycyclic aromatic hydrocarbon and polychlorinated biphenyl bioaccumulation in Mya arenaria and application for site assessment in conjunction with sediment quality screening criteriaLevine, Rachel H January 1999 (has links)
Thesis (M. Eng. in Ocean Engineering)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Mechanical Engineering; and the Woods Hole Oceanographic Institution), 1999. / Includes bibliographical references (leaves 97-103). / by Rachel H. Levine. / M.Eng.in Ocean Engineering
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CHARACTERIZATION AND RISK ASSESSMENT OF ATMOSPHERIC POLLUTANTS IN KLANG VALLEY,MALAYSIA / マレーシア、クラン渓谷における、大気汚染物質の特性評価およびリスクアセスメントMuhammad Ikram Bin A Wahab 24 September 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18577号 / 工博第3938号 / 新制||工||1605(附属図書館) / 31477 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 米田 稔, 教授 高野 裕久, 教授 清水 芳久 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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Synthesis and Functionalization of Fused Aromatic Ring-layered Compounds / 縮環芳香環積層分子の合成とその機能化Tatsuya, Nakano 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19006号 / 工博第4048号 / 新制||工||1623(附属図書館) / 31957 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 中條 善樹, 教授 赤木 和夫, 教授 秋吉 一成 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
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