Thèses : « Polyaromatic hydrocarbones »

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Mistry, Anish. « Non-Kekulé polyaromatic hydrocarbons ». Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/88089/.

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Non-Kekulé PAHs have been studied for a variety of applications due to the interesting chemistry they possess for such simple organic molecules. PAHs can have both closed and open-shell arrangements which have been of interest recently due to the potential magnetic and electronic properties they can acquire. Due to this, there has recently been a strong interest in graphene which can be viewed as a sheet of PAHs fused together. This thesis describes the formation of particular PAHs including open-shell compounds and how PAHs can be fully characterised using one technique. Chapter 2 describes the synthesis of 6H-benzo[cd]pyrene, the starting point of this project. Pentacene and perylene are other five fused ring structures like 6H-benzo[cd]pyrene which are commonly used due to their fluorescence, thus, this PAH could have interesting properties for material scientists. The production of the benzo[cd]pyrene radical by AFM/STM is then described. Chapter 3 describes peri-condensation reactions to form larger PAHs a technique which was commonly used in the 1900s for the addition of an aromatic ring, however, multiple ring additions have been reported to occur. In addition, carbon labelling experiments have been completed to confirm this and the mechanism by which multiple rings add have been discussed. STM/AFM has been used to characterise the compounds formed in the peri-condensation reactions as common techniques for characterisation do not provide enough structural data for compound determination. Chapter 4 discusses the synthesis of 3,8-dihydro-3H,8H-dibenzo[cd,mn]pyrene. Thereafter the use of AFM/STM is then utilised to dehydrogenate 3,8-dihydro-3H,8H-dibenzo[cd,mn]pyrene to form the non-Kekulé structure of triangulene which was simultaneously imaged for the first time.

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Wang, Cong. « Synthesis of Polyaromatic Hydrocarbons via Mechanochemistry ». University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1563525733261563.

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Riaz, Ihsan. « Bioremediation treatments for polyaromatic hydrocarbons contaminated soil ». Thesis, Glasgow Caledonian University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251186.

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Gazdošová, Lucie. « Studium chemického složení atmosférických aerosolů ». Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216356.

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Atmospheric aerosols play an important role in various atmospheric issues (effect to the radiation budget of the atmosphere, visibility reduction, smog production, destruction of stratospheric ozone, …). Epidemiological studies proved a correlation between increased mortality and high concentration of ambient particulate matter. Over the past decade, a growing attention has been focused on the organic compounds that are constituents of aerosol particles. Although organic compounds comprise often up to 60% of the total aerosol mass, their composition, concentration and formation mechanisms are not well understood. Diploma thesis will deal with the study of chemical composition of organic compounds bound to atmospheric aerosols with focus on polyaromatic hydrocarbons and sugars. Atmospheric aerosols will be sampled on filters and filter extracts will be analysed for content of studied organic compounds by means of GC, GC-MS or LC, respectively. Development and optimalization of extraction methods (PSE, …) and detection of compounds of interest. Concentration of studied organic compounds in aerosol size fractions PM 10, PM 2.5 and PM 1 will be compared.

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Yuan, Tao 1968. « Remediation of a soil contaminated with polyaromatic hydrocarbons (PAHs) ». Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=111845.

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Sites contaminated with polyaromatic hydrocarbons (PAHs) pose serious health and safety risks to the surrounding environment due to their toxicity, persistence and accumulation in the environment. Because certain members of this class have been demonstrated to be both carcinogenic and mutagenic, PAHs are considered as environmental priority pollutants (US EPA). The studies in this thesis provide an efficient, economical and environmentally benign technique for the remediation of PAH contaminated soil/sediment by means of PAH mobilization with surfactant followed with a catalytic hydrogenation in supercritical carbon dioxide (scCO2).
Catalytic hydrogenation of naphthalene, acenaphthylene, ancenaphthene, anthracene, phenanthrene, chrysene and benzo[a]pyrene over alumina supported palladium (5% Pd0/gammaAl2O3) commercial catalyst were investigated in either a batch reaction mode or a continuous reaction system in H2-scCO2 (∼5% v/v). The hydrocarbon compounds were efficiently reduced to their corresponding fully saturated polycyclic hydrocarbon homologs with mild conditions of temperature (90°C) and pressure (60 psi H2 or 3000 psi H2-scCO2). The bacterial reverse mutation assay demonstrated that both the fully and partially hydrogenated products of chrysene and benzo[a]pyrene were devoid of mutagenic activity.
A laboratory study was conducted on the surfactant-assisted mobilization of PAH compounds combined with reagent regeneration and detoxification steps to generate innocuous products. Five minutes of ultrasonication of field contaminated soil with a 3% (w/v) surfactant suspension mobilized appreciable quantities of all PAH compounds. Formulating the Brij 98 surfactant in 0.1 M phosphate buffer (pH 8.0) mobilized the largest quantities of PAH compounds and the recovery of surfactant (>90%) but soil residues exceeded permissible maxima for five- and six-ring analytes. Five successive washes were required to reduce the residual fraction to permissible levels. The mobilized PAH compounds were then detoxified at line by catalytic hydrogenation in a 5% H2-scCO2 (v/v) atmosphere.
New palladium hydrogenation catalysts were fabricated in the laboratory with specific processes on various supports. The hydrogenation of phenanthrene and benzo[a]pyrene in a fixed bed micro reactor demonstrated that the catalyst that was fabricated from organosoluble precursor loaded on aluminum oxide (2.5% Pd0/gammaAl2O3) was four times more efficient than the commercial catalyst that was used for PAH hydrogenations.

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Sundqvist, Björn. « POLYAROMATIC HYDROCARBONS IN HYDROCHARS : HYDROTHERMAL CARBONIZATION OF SEWAGE SLUDGE ». Thesis, Umeå universitet, Kemiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-185521.

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Sewage sludge is an inevitable by-product from waste water treatment plants. Sludgemanagement is a difficult task since sludge has a high moisture content, poordewaterability and generally contain heavy metals, pharmaceutical residues,polyfluorinated alkyl substances (PFAS) and organic pollutants. Recentlyhydrothermal carbonization (HTC) has been getting attention for its suitability to treatsewage sludge. HTC is a flexible process which can handle feedstocks with highmoisture content. The process stabilizes the organic content in a solid residue calledhydrochar which has an increased energy content and decreased moisture contentcompared to the starting material. Hydrochar can be used as soil amendment materialsince it has a good nutrient content and can prevent leaching of fertilizers. However,there is a concern for the risk of high levels of poly aromatic hydrocarbons (PAHs) inthe hydrochar which might limit its applicability in soil applications. PAHs are acomplex group of organic pollutants that can be toxic and even cancerogenic tohumans. 16 PAHs have been described as priority pollutants by the US EnvironmentalProtection Agency due to their toxicity and risk for human exposure. In this studyHTC was performed, with municipal sewage sludge as feedstock, at different processconditions to investigate its influence on the PAH content in the produced hydrocharsand aqueous residues. Ten experiments were performed with varying reactiontemperature (ranging from 180 °C to 260 °C fixed at 1 h residence time) and varyingresidence time (ranging from 1 h to 5 h fixed at 200 °C and 260 °C). The PAH contentof the products was analysed using GC/MS. The hydrochars suitability for soil amendment was investigated. At a 1.7wt.%amendment level (approximately 60 tons/hectare) the results showed that the PAHcontribution from the hydrochars to the soil was well below the SwedishEnvironmental Protection Agency (SEPA) contamination guidelines. No significantPAH content in the products, that might limit the hydrochars applicability for landusages, was observed. The content of the 16 priority PAHs (PAH 16) in thehydrochars were below the international biochar (IBI) limit (6mg/kg TS) and theEuropean Biochar Certificate (EBC) EBC-Agro limit (6mg/kg TS). The PAH contentof the filtrates where below the Swedish Petroleum institute (SPI) irrigationguidelines, except for the filtrate produced at 260 °C, 5 h. In the raw material no PAHspecies was found, however, the reporting limit was higher compared to thehydrochars. Overall, the content of PAH was lower in the filtrates compared to thehydrochar, e.g. at 200 °C, 1 h the content PAH M were 0.05 and 0.85 mg/kg sludgeTS for the filtrate and hydrochar respectively. This was expected since PAHsgenerally has a low solubility in water. To assess the toxicity of the hydrochars thetoxic equivalent quantity (TEQ) was used. The TEQ for the hydrochars wereapproximately ~0.0 to 0.68 mg/kg TS which is below the IBI limit level at 3.0 mg/kgTS. Temperatures around 200 °C to 220° C were found to be favourable in terms ofPAH content in the hydrochar, at 220 °C and 1 h the sum of PAH16 is lower than forall other samples, for both the hydrochar and the filtrate (<R.L and 0.01mg/kg sludgeTS for the hydrochar and filtrate respectively). No significant correlation betweenresidence time and PAH content was observed, except at 260 °C where the PAH16content increased significantly in the filtrates between 1 h and 5 h residence time(0.05 to 0.85 mg/kg sludge TS). In conclusion, HTC was found to be a promisingprocess for utilizing sewage sludge and the results indicates that the risk of high levelsof PAH content of the hydrochars are relatively low.

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Roberson, Luke Bennett. « Ultrapurification and deposition of polyaromatic hydrocarbons for field effect transistors ». Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/30950.

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Miller, David J. « Effect of oil age on polyaromatic hydrocarbon emissions from automobiles ». Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/101130.

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Automobiles are known to emit polyaromatic hydrocarbons. The literature indicates that the emission levels of these compounds are correlated with oil age, and it has been hypothesized that entry of oil into the combustion chamber is a major cause of these emissions. This experiment investigated the relationship between oil age and these polyaromatic hydrocarbon emissions. It was found that the three polyaromatics of interest seem to be emitted inconsistently and irregularly. It is possible that this was due to a buildup on the combustion chamber walls of these compounds: polyaromatics are formed in the quench layer near these walls and can accumulate there until dynamic equilibrium is reached. This may not have been reached at the time of the investigation since the engine was relatively new. This would be of interest for future investigations.
M.S.

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Crosswell, Scott Brownlee. « Effects of Grasses on the Remediation of Creosote-Contaminated Surface Soil ». Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/42643.

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A grass phytoremediation field study was initiated in July 1997 at the site of a former railroad tie facility that used creosote for tie preservation. The site is contaminated with polycyclic aromatic hydrocarbons (PAHs). A test matrix consisting of 36 planted (clover, fescue and rye grasses) and unplanted cells was established. The focus of the study was to evaluate PAH remediation in fertilized plots that were unplanted or seeded with clover, fescue or rye. Samples were collected from a depth of 15 to 21 cm, and the six most prevalent PAHs, acenaphthene, fluorene, phenanthrene, fluoranthene, pyrene and chrysene were quantified. Data from four sampling periods, t=0, 9, 12 and 17 months is presented. At t=9 months, substantial loss of the five lowest molecular weight (LMW) PAHs had occurred, and the loss was attributed to natural attenuation. During the first 9 months, below average precipitation at the site delayed grass root development. Between t=9 and 12 months, above average precipitation was recorded and this appeared to accelerate chrysene removal rates in both the unplanted and planted cells; however, the rate was higher rate in the planted cells. Similarly, fluoranthene and pyrene degradation seemed to be enhanced in the fescue and rye cells. Over the last 8 months of the study, acenaphthene, fluorene and phenanthrene concentrations approached constant, minimum levels suggesting additional removal will be limited. PAH compounds with higher solubility correlated to decreased constituent soil concentrations. Additional sampling was initiated at t=17 months to compare PAH concentrations with depth. This was done because the observed root mass changed significantly with depth. Samples were taken at two additional depths 10 to 15 and 32 to 38 cm. Increased removal of fluoranthene and pyrene was observed in the uppermost zone, suggesting a role for plants in remediation of these 4 ringed PAHs.
Master of Science

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Pritchett, Blair. « Mutagenic and genotoxic potential of nitrated polyaromatic hydrocarbons in combustion byproduct mixtures ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0021/MQ55538.pdf.

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Wang, Jiann-Ming. « Intrinsic and enhanced biodegradation of polyaromatic hydrocarbons in aqueous and soil systems ». Diss., The University of Arizona, 1999. http://hdl.handle.net/10150/284046.

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Bioremediation is currently one of the most popular methods for remediating soil and groundwater contaminated by organic compounds. However, it has been found that the availability of the target contaminant to the microbial populations capable of degrading the compound may serve as a limiting factor in many systems. Thus, there is interest in the use of solubilization agents for enhancing bioavailability of organic contaminants. The impact of hydroxypropyl-β-cyclodextrin (HPCD) on the biodegradation of polycyclic aromatic hydrocarbons (PAHs) was investigated in a batch study. Results showed that HPCD can significantly increase the apparent solubility of phenanthrene, which had a major impact on the biodegradation rate of phenanthrene. For example, in the presence of 10⁵ mg L⁻¹ HPCD, the substrate utilization rate increased 5.5 times and only 0.3% of the phenanthrene remained at the end of a 48-hour incubation. It strongly suggests that HPCD can significantly increase the bioavailability, and thereby enhance the biodegradation, of phenanthrene. Biodegradation is often of great importance for the transport, fate, and remediation of organic contaminants in the subsurface. When modeling biodegradation processes, it is usually assumed that the microbial population responsible for biodegradation is composed of a single species. However, this is unlikely to be true for many, if not most, field situations. The effect of multiple species of degraders on phenanthrene biodegradation and transport in a saturated soil (with a high phenanthrene sorption capacity) was evaluated with a series of miscible-displacement experiments. Breakthrough curves obtained for the non-sterile column experiment exhibited oscillations in microbial populations as well as in oxygen and phenanthrene concentrations during the 6 months of continuous injection of a constant-concentration phenanthrene solution. This behavior is due to the response of the heterogeneous bacterial population (24 species) to substrates and oxygen availability, wherein population dynamics is hypothesized to be mediated by competition and other multi-species interactions. The dynamics of heterogeneous microbial populations, especially under growth conditions, should be considered when evaluating contaminant biodegradation and transport in natural subsurface systems.

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Silva, Maria João Cerqueira da. « Polyaromatic hydrocarbons in hepatic tissues of Etmopterus pusillus and Galeus melastomus : multibiomarker analysis ». Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22689.

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Mestrado em Biologia Molecular e Celular
Um dos maiores ecossistemas do planeta, o marinho, apresenta uma biodiversidade enorme e é uma fonte de diversos recursos naturais. Hoje em dia, este ecossistema tornou-se relevante devido ao facto de ser alvo de inúmeras pressões antropológicas. Os tubarões são um dos predadores que estão no topo das cadeias alimentares marinhas, e estão constantemente a absorver contaminantes como consequência da bioacumulação nas redes tróficas. Etmopterus pusillus e Galeus melastomus no Oceano Atlântico estão a sofrer os efeitos da bioacumulação dos hidrocarbonetos poliaromáticos (PAH´s). Por essa mesma razão, no presente estudo foram avaliados um número de biomarcadores como objetivo de estabelecer uma relação entre os níveis de PAH´s e a ocorrência de stress oxidativo em elasmobrânquios. Na pesca comercial, foram capturados 37 indivíduos de Etmopterus pusillus (23 machos e 14 fêmeas) e 15 indivíduos de Galeus melastomus (todos fêmeas) no Oceano Atlântico, nos arredores da costa de Sesimbra. O tecido hepático foi colhido e congelado a -80°C. As amostras hepáticas foram divididas em três grupos de idade: juvenis, adultos e séniores, separados de acordo com o seu peso e tamanho individual. Neste estudo, alguns PAH´s foram quantificados como, naftaleno, pireno, fenantreno e benzo[a]pireno através do método fluorimétrico. Os PAH´s foram detetados em todas as amostras de tecido hepático dos juvenis, adultos e sénior e em ambas as espécies. Visto que foram detetados níveis de PAH´s, diferentes indicadores de stress oxidativo foram quantificados: atividade da catálase (CAT), catividade da glutationa s-transferase (GST), glutationa total (TG), peroxidação lipídica (LPO), sistema transportador de eletrões (ETS), hidratos de carbono (HC) e lípidos. Nos tecidos hepáticos de Etmopterus pusillus foi observado que CAT, GST e LPO aumentam no grupo dos adultos. Contrariamente, TG , ETS e lipidos diminuem no grupo adulto quando comparados com os juvenis. Relativamente ao Galeus melastomus foi observado que GST e LPO diminuem no grupo dos adultos quando comparados com os juvenis. Como a acumulação de PAH´s nos tecidos hepáticos foi detetada e foram encontradas diferenças significativas nos níveis das defesas antioxidantes, isto pode indicar uma relação entre eles, e um eventual estado de stress oxidativo desta população de elasmobrânquios.
One of the biggest ecosystems on the planet, the marine ecosystem, represents huge diversity and is a source of many different natural resources. Today, this ecosystem has become relevant due to the fact that planet ecosystems are a target of several anthropogenic pressures. Sharks are one of the top predators in marine food chain, constantly absorbing contaminants as a consequence of bioaccumulation on trophic nets. Etmopterus pusillus and Galeus melastomus in the Atlantic Ocean are suffering the effects of polyaromatic hydrocarbons (PAH´s) bioaccumulation. For that reason, in the present report were evaluated a number of different biomarkers in order to stablish the relationship between PAH´s levels and the occurrence of oxidative stress in elasmobranchs. In commercial fishing, 37 individuals of Etmopterus pusillus (23 males and 14 females) and 15 individuals of Galeus melastomus (all females) were captured in the Atlantic Ocean, off the coast of Sesimbra. Hepathic tissue was collected and frozen at -80°C. Hepathic samples were split into three age groups: juveniles, adults and seniors, split according to the specimen’s total weight and size. In this study, several PAH´s were quantified, such as naphthalene, pyrene, phenanthrene and benzo[a]pyrene content by a fluorimetric method. PAH´s were detected in hepathic tissue samples of juveniles, adults and seniors group in both species. Since PAH´s accumulation in liver tissue were detected, different stress oxidative parameters were quantified: catalase activity (CAT), glutathione stransferase activity (GST), total glutathione (TG), lipid peroxidation (LPO), electron transport system (ETS), hydrocarbons (HC) and lipids. In hepathic tissue of Etmopterus pusillus it was observed that CAT, GST and LPO increased in adult group. Conversely, TG, ETS and lipids decreased in adult group when compared with juvenile group. Relatively to Galeus melastomus, it was observed that GST and LPO decreased in adult group when compared with juvenile group. As PAH´s accumulation in hepathic tissues were detected and significant differences in antioxidant defense levels were found, it might indicate a relationship between them, and eventually an oxidative stress state of elasmobranch´s population.

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Jacquiau, Hervé Roland. « A novel cloning system and its use in polyaromatic hydrocarbon-utilising Rhodococcus ». Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621838.

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Mastran, Trina Ann. « Distribution of petroleum products with respect to boating activity in a reservoir ». Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-08222009-040425/.

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Yeatts, Karin Beatrice. « An investigation of structure activity relationships for aryl nitrenium stability and mutagenicity for amino polyaromatic hydrocarbons ». Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-02132009-170829/.

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Warne, Michael St John. « Mechanism and Prediction of the Non-Specific Toxicity of Individual Compounds and Mixtures ». Thesis, Griffith University, 1991. http://hdl.handle.net/10072/365986.

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The toxicity of a range of hydrocarbons, phenols and pyridines were assessed. Such chemicals are classed as non-specific toxicants ie. they are neither an acid, base or a salt. Non-specific toxicants exert their toxicity by a mechanism termed narcosis. The toxicity of the test compounds to a mixed marine bacterial culture (containing thirteen different strains) was assessed both individually and in mixtures under static conditions. Thus, the reported toxicity values were actually the average toxicity of a compound or mixture to the thirteen different strains of bacteria. For homologous series of chemicals the toxicity tended to increase with increasing molecular weight until a point was reached beyond which a toxic effect could no longer by exerted. Evidence was presented that this cut off effect may not be due to aqueous solubility limiting accumulation of the toxicant but rather a volume based mechanism. The toxicity of structural isomers were different. These findings are suggestive of a more specific mechanism of action than narcosis. The toxicity of eighteen different mixtures of the test compounds were found to generally be synergistic. A currently accepted model for the toxicity of mixtures states that the toxicity of mixtures composed of toxicants with the same mechanism of action should be additive. Based on the observed mixture toxicity data and the above principle the test compounds exerted their toxicity by three different mechanisms of action. The compounds that exerted their toxicity in the same manner were: firstly polyaromatic hydrocarbons, 1-alkenes, alkyl-substituted benzenes and alkyl-substituted naphthalenes, secondly alkyl-substituted phenols and thirdly alkyl-substituted pyridines. The non-additive toxicity of mixtures composed of structural isomers indicates that structural isomers have different mechanisms of action; which is unusual considering the degree of chemical and structural similarity. High quality relationships were developed to predict the toxicity of individual compounds as well as other environmentally important properties ie. aqueous solubility and octanol-water partition coefficients. Relationships were developed using high performance liquid chromatography (HPLC) capacity factors. HPLC columns containing different stationary phases were combined in series, for the first time, and successful relationships with toxicity developed. This is a significant finding as it indicates there is the potential to specifically design stationary phases to reflect particular properties of the system being modelled. Relationships to describe the toxicity of mixtures were not of as high quality as those for individual compounds, but were satisfactory. A problem with such relationships is that it is difficult to infer a mechanism of action. The exact mechanism of action for non-specific toxicants remains unclear, despite being the subject of extensive research throughout this century. There are currently three major hypotheses for the mechanism of action; the critical concentration, critical volume and the protein binding hypotheses. Whichever, of the hypotheses is correct should be able to explain the toxicity of mixtures of non-specific toxicants as well as that for individual compounds. The ability of the critical concentration and volume hypotheses to describe the toxicity of individual compounds and mixtures was assessed by comparing literature data with predictions based on each of the hypotheses. The critical volume hypothesis, which states that toxicity occurs when the volume of target tissue increases to a certain volume due to the presence of a toxicant, was better able to describe the toxicity of non-specific toxicants. QSARs based upon parameters that measure the change in volume of a solution due to the presence of a solute (partial molar volume) were derived for the toxicity of individual compounds and mixtures. Both relationships lent further support to the critical volume hypothesis. A new hypothesis, called the funnel hypothesis, based upon the principles of the critical volume hypothesis and explaining the toxicity of mixtures in terms of partial molar volume was developed. This hypothesis is mechanistic and led to several predictions about the toxicity of equitoxic and non-equitoxic mixtures. Of these, the predictions for equitoxic mixtures were confirmed based upon comparison of the hypothesis' predictions and available literature toxicity data. Testing the validity of predictions for non-equitoxic mixtures was not possible due to the paucity of non-equitoxic mixture toxicity data. The predictions of the funnel hypothesis are: 1) the probability of a mixture, composed of non-specific toxicants with different mechanisms of action, deviating from toxic additivity will increase as the number of components decreases. The magnitude of the deviation is also likely to increase as the number of mixtures decreases. 2) the probability of a mixture, composed of non-specific toxicants with different mechanisms of action, deviating from toxic additivity will increase as the concentration of the components increases. The magnitude of the deviation is also likely to increase as the concentration increases.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Australian Environmental Studies
Science, Environment, Engineering and Technology
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Heltsley, Rebecca. « Study of Polyaromatic Hydrocarbons Emitted in the Fly Ash from Coal Combustion in a Fluidized Bed Combuster ». TopSCHOLAR®, 2000. http://digitalcommons.wku.edu/theses/718.

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Exposure to Polyaromatic Hydrocarbons (PAHs) has long been identified as an environmental concern because of their carcinogenic and mutagenic effects. The Environmental Protection Agency (EPA) has developed a list of 16 PAHs that are found on the Priority Pollutant List due to the extensive amount of data suggesting the hazards of these compounds. These toxic compounds are often emitted into the atmosphere by anthropogenic sources, such as combustors. Therefore, analysis of these compounds must be conducted during coal combustion. Two 1000-hour coal combustion burns were performed using the 0.1 MWth bench-scale fluidized bed combustor (FBC), which is found in the Combustion Laboratory at Western Kentucky University. The data contained in this thesis were collected from burning coal 97025 and coal 99626 for 1000-hour experiments. The fly ash produced from the combustor was examined as the media for the PAHs. It was collected by an in-situ cyclone sampler that was attached to various ports along the combustor during specific conditions in the combustor. Once the fly ash was collected it was analyzed with two different extraction methods. Solvent extraction was the first method used in this study. Dichloromethane was the solvent used to extract the PAHs in the fly ash. Once the extraction was completed, GC/MS in the selective ion monitoring (SIM) mode was used to analyze the extract. The other method used to extract the PAHs from the fly ash was the thermal extraction method. This method allows direct analysis of the PAHs without any use of a solvent. The GC/TOFMS was used to analyze the samples that were extracted by the thermal extraction method. In this study, the effects of combustion temperature, combustion bed height, sampling height, excess air ratio, and fluidizing velocity were examined to determine how each of these parameters affected the release of PAHs in the fly ash. The results indicated that the parameters investigated have a major influence on the production of PAHs in the combustor. As combustion efficiency decreases, larger PAHs (four to five fused rings) are detected in the fly ash; whereas, during high efficiency combustion, smaller PAHs (two to three fused rings) are more likely to be detected.

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Treanor, Michael-John. « Thermally activated chemical pathways of polyaromatic hydrocarbons on a reactive surface : the assembly of intermediates towards graphene ». Thesis, University of St Andrews, 2017. http://hdl.handle.net/10023/16088.

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Křůmal, Kamil. « Analýza organických markerů pro identifikaci zdrojů atmosférických aerosolů ». Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-233323.

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In this work the organic markers that serve for identification of sources of aerosols are monitored. Theoretic part deals with detailed survey of organic markers emitted from the most significant sources of atmospheric aerosols (biomass combustion, combustion of fossil fuels and traffic) as well as with sampling of aerosols and analysis of organic markers by analytical techniques. Monosaccharide anhydrides (emissions from biomass combustion) and polyaromatic hydrocarbons (emissions from traffic and incomplete combustion) were observed especially. Hopanes and steranes (traffic, coal combustion) and fatty acids (cooking) were next groups of monitored organic markers. Markers were studied mainly in size fraction PM1 because this fraction of aerosols is the most harmful to human health. Aerosols were sampled in two seasons (winter and summer) in two towns in 2009. Higher concentrations of aerosols and organic compounds were found in winter season, which resulted from increased combustion of biomass, coal and other organic material while traffic was the most significant source of aerosols in summer.

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Poltorak, Matthew Robert. « Field and Greenhouse Studies of Phytoremediation with California Native Plants for Soil Contaminated with Petroleum Hydrocarbons, PAHs, PCBs, Chlorinated Dioxins/Furans, and Heavy Metals ». DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1338.

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Native and naturalized California plant species were screened for their phytoremediation potential for the cleanup of soil contaminated with petroleum hydrocarbons (PHCs), poly-aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), chlorinated dioxins/furans, and heavy metals. This screening was followed by controlled greenhouse experiments to further evaluate the phytoremediation potential of the best candidates. Field specimens and soils used for this study were collected from the former Energy Technology Engineering Center (ETEC) at the Santa Susana Field Laboratory in Southern California that was operated by the Department of Energy (DOE). Soils at this site contain all of the contaminants of interest (COIs). Nine plant species were screened in the field: Purple Needlegrass (Nassella pulchra), Blue Elderberry (Sambucus nigra), Laurel Sumac (Malosma laurina), Mule Fat (Baccharis salicifolia), Palmer’s Goldenbush (Ericameria palmeri), Summer Mustard (Hirschfeldia incana), Narrowleaf Milkweed (Asclepias fascicularis), Coyote Brush (Baccharis pilularis), and Thickleaf Yerba Santa (Eriodictyon crassifolium). In the field three samples of each species growing in contaminated soil and one of each species growing in uncontaminated soil were selected for harvesting and analysis. The roots, above ground plant tissue, and soil around the roots were sampled separately and analyzed for the COIs: PHCs, PAHs, PCBs, chlorinated dioxins/furans, and metals (which include mercury, silver, cadmium, and lead). All of the plants in the field appeared to generate compounds which result in higher measured PHC concentrations than those measured in the associated soil. The highest concentrations of PAHs in the roots were observed for Blue Elderberry (1740 ug/kg), Purple Needlegrass (703 ug/kg), and Yerba Santa (200 ug/kg). No uptake of PCBs was observed in the roots or foliage of any species. The highest concentrations of total chlorinated dioxins/furans in the roots were observed for Purple Needlegrass (2237 ng/kg), Blue Elderberry (1026 ng/kg), Palmer’s Goldenbush (432 ng/kg), and Yerba Santa (421 ng/kg). The highest concentrations of total chlorinated dioxins/furans in the foliage were observed for Yerba Santa (901 ng/kg), Palmer’s Goldenbush (757 ng/kg), and Purple Needlegrass (694 ng/kg). No uptake of mercury was observed in the roots or foliage of any species. The highest concentration of silver in the roots was observed for Laurel Sumac (7.34 mg/kg). Summer Mustard (SM) was the only species that showed uptake of silver into the foliage (0.405 mg/kg). The highest concentrations of cadmium in the roots and foliage were observed for Mule Fat (1.84 mg/kg and 3.64 mg/kg) and Coyote Brush (1.52 mg/kg and 2.12 mg/kg) and the greatest concentration of lead in the roots and foliage was observed for Purple Needlegrass (8.92 mg/kg and 1.17 mg/kg). Plants with a wide variety of observed contaminant uptake in the field were selected for a second phase of research in which three of the most promising species were grown in greenhouse microcosms to quantify the removal of contaminants from the soil. The three species selected based on preliminary results from the field study were Coyote Brush, Mule Fat, and Purple Needlegrass. Microcosms consisted of 2.17 kg of soil in 4-L glass jars with glass marbles for an underdrain. Plants were watered with deionized water and no leachate was collected. Five replicates of each microcosm type were created and incubated for 211 days with soil sampling at 85 and 211 days. Soil, plant roots/above ground tissue, and volatilization from the plants were analyzed for COIs to determine the mechanisms of phytoremediation. One set of microcosms was used to test the effect of addition of achelating agent (ethylenediaminetetraacetic acid) and another set was used to test the effect of fertilizer addition on phytoremediation potential. Three control treatments were tested: sterilized (gamma irradiation) soil planted with Purple Needlegrass, unplanted soil, and sterilized unplanted soil. None of the plant species demonstrated volatilization of COIs under these conditions. Volatilization of mercury was not tested for. The average PCB concentration (measured as Aroclor 1260) reductions in soils with Purple Needlegrass and chelated Coyote Brush were 49.4% and 51.4% respectively (p < 0.05). However, the sterilized unplanted control also had a decrease of Aroclor 1260 concentrations in the soil of 36.6% (p < 0.05). None of the species phytoextracted PCBs, so the mechanism of PCB remediation appears to be phytostimulation of the rhizosphere. Purple Needlegrass showed the greatest uptake of dioxins/furans into the foliage but did not appear to reduce the dioxin/furan concentrations in the soil. Coyote Brush, fertilized Coyote Brush, and Mule Fat also showed uptake of dioxins/furans into the roots and foliage. Only the Coyote Brush and fertilized Coyote Brush significantly (p = 0.036, p = 0.022) reduced the total dioxin/furan concentration in the soil (17.8% and 19.8% respectively). Coyote Brush may have stimulated microbes in the rhizosphere to better degrade the dioxins/furans. None of the plants were identified as hyper-accumulators of metals, and none of the soil metal concentrations significantly decreased in any of the microcosms. All of the metals (except mercury) were taken into the roots of plants to some degree, with Purple Needlegrass showing the most promise for metal extraction as it showed some of the highest concentrations of metals in roots and was the only species that contained mercury and silver in the foliage. This study suggests that there is some potential for phytoremediation of PCBs and chlorinated dioxins/furans. The results for petroleum hydrocarbons were inconclusive. Metal uptake was not substantial enough to lower metal concentrations in the soils. Thus phytoremediation of COIs at the site is limited and more aggressive forms of remediation may be required to reduce the concentrations of COIs quickly.

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Furlan, Bianca. « Biodegradação de naftaleno, fenantreno e diesel por isolados do gênero Burkholderia da Amazônia / ». Rio Claro : [s.n.], 2011. http://hdl.handle.net/11449/95001.

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Resumo: O gênero Burkholderia compreende um grupo de bactérias muito diversificado, ocupando vários nichos ecológicos e possui espécies que causam doenças, mas outras espécies apresentam habilidades importantes para os ramos da agricultura, biotecnologia e do ambiente, como a biodegradação. Essas bactérias são morfologicamente semelhantes e o gênero está dividido em dezessete genomovars, onde espécies semelhantes geneticamente são agrupadas, formando o Complexo Burkholderia cepacia (CBC). Por meio de estudos moleculares do gene 16S rRNA e do gene recA foi possível fazer a classificação adequada em espécies dos 450 isolados obtidos da Terra Preta Antropogênica (TPA) e adjacentes, em quatro sítios (TPA Caldeirão Cultivado; TPA Caldeirão Capoeira; TPA Hatahara e TPA Mina-I), foram obtidos 177 isolados do gênero Burkholderia. Desses isolados, pela análise do gene 16S rRNA foi possível classificar 157 isolados ao nível de espécie e pela análise do gene recA somente 105 isolados foram classificados neste mesmo nível. Esses isolados foram utilizados no teste de biodegradação dos hidrocarbonetos. Os hidrocarbonetos poliaromáticos (HPAs) são compostos orgânicos resultantes da combustão incompleta da matéria orgânica e dos derivados de petróleo, são pouco solúveis em água e muito tóxicos para as células, por isso, não são metabolizados por muitos micro-organismos e acabam contaminando e inviabilizando os ambientes. Nos testes de biodegradação os substratos utilizados foram o naftaleno, o fenantreno e o diesel, juntamente com o indicador redox 2,6- diclorofenol-indofenol (DCPIP), que sofre descoloração (de azul para incolor) quando as células utilizam os substratos como fonte de carbono para o crescimento celular, gerando elétrons que vão reduzir o indicador. Pela análise do teste, 19 isolados degradaram o naftaleno, 16 degradaram... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The genus Burkholderia comprises a very diverse group of bacteria occupying various ecological niches and has species that cause disease, but other species have important skills to the branches of agriculture, biotechnology and the environment, as biodegradation. These bacteria are morphologically similar genus and is divided into seventeen genomovars, where genetically similar species are grouped together, forming the Burkholderia cepacia complex (BCC). Through molecular studies of 16S rRNA and recA gene was possible to make the appropriate classification of species in 450 isolates of Terra Preta Antropogênica (TPA) and adjacent at four sites (TPA Caldeirão Cultivado; TPA Caldeirão Capoeira; TPA Hatahara e TPA Mina-I) were obtained 177 isolates of the genus Burkholderia. These isolates by 16S rRNA gene analysis was possible to classify 157 isolates to species level and the recA gene analysis only 105 isolates were classified in the same level. These isolates were used to test the biodegradation of hydrocarbons. Polyaromatic hydrocarbons (PAHs) are organic compounds resulting from incomplete combustion of organic matter and petroleum derivatives, are not very soluble in water and very toxic to cells, therefore, are not metabolized by many microorganisms to contaminate and render environments. In biodegradation tests the substrates used were naphthalene, phenanthrene and the diesel, along with the redox indicator 2,6- dichlorophenol-indophenol (DCPIP), who suffers discoloration (blue to colorless) when cells use the substrates as a source of carbon for cell growth, generating electrons that will reduce the indicator. By analysis of the test, 19 isolates degraded naphthalene, phenanthrene degraded the 16 and 126 degraded diesel, generating a total of 132 isolates of the genus Burkholderia that have the ability to degrade at least... (Complete abstract click eletronic access below)
Orientador: Dejanira de Franceschi de Angelis
Coorientador: Siu Mui Tsai
Banca: Margarete de Fátima Costa
Banca: Eleonora Cano Carmona
Mestre

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Ioannidou, Despoina. « Characterization of environmental inequalities due to Polyaromatic Hydrocarbons in France : developing environmental data processing methods to spatialize exposure indicators for PAH substances ». Thesis, Paris, CNAM, 2018. http://www.theses.fr/2018CNAM1176/document.

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La réduction des inégalités d’exposition environnementale constitue un axe majeur en santé publique en France comme en témoignent les priorités des différents Plan Nationaux Santé Environnement (PNSE). L’objectif de cette thèse est de développer une approche intégrée pour la caractérisation des inégalités environnementales et l’évaluation de l’exposition spatialisée de la population aux HAP en France.Les données produites dans le cadre des réseaux de surveillance de la qualités des milieux environnementaux sont le reflet de la contamination réelle des milieux et de l’exposition globale des populations. Toutefois, elles ne présentent généralement pas une représentativité spatiale suffisante pour caractériser finement les expositions environnementales, ces réseaux n’ayant pas été initialement conçus dans cet objectif. Des méthodes statistiques sont développées pour traiter les bases de données d’entrée (concentrations environnementales dans l’eau, l’air et le sol) et les rendre pertinentes vis à vis des objectifs définis de caractérisation de l’exposition. Un modèle multimédia d’exposition, interfacé avec un Système d’Information Géographique pour intégrer les variables environnementales, est développé pour estimer les doses d’exposition liées à l’ingestion d’aliments, d’eau de consommation, de sol et à l’inhalation de contaminants atmosphériques. La méthodologie a été appliquée pour trois Hydrocarbures Aromatiques Polycycliques (benzo[a]pyrène, benzo[ghi]pérylène et indéno[1,2,3-cd]pyrène) sur l’ensemble du territoire français. Les résultats permettent de cartographier des indicateurs d’exposition, d’identifier les zones de surexposition et de caractériser les déterminants environnementaux. Dans une logique de caractérisation de l’exposition, la spatialisation des données issues des mesures environnementales pose un certain nombre de questions méthodologiques qui confèrent aux cartes réalisées de nombreuses incertitudes et limites relatives à l’échantillonnage et aux représentativités spatiales et temporelles des données. Celles-ci peuvent être réduites par l’acquisition de données supplémentaires et par la construction de variables prédictives des phénomènes spatiaux et temporels considérés.Les outils de traitement statistique de données développés dans le cadre de ces travaux seront intégrés dans la plateforme PLAINE pour être déclinés sur d’autres polluants en vue de prioriser les mesures de gestion à mettre en œuvre
Reducing environmental exposure inequalities has become a major focus of public health efforts in France, as evidenced by the French action plans for health and the environment. The aim of this thesis is to develop an integrated approach to characterize environmental inequalities and evaluate the spatialized exposure to PAH in France.The data produced as part of the monitoring quality networks of environmental media reflect the actual contamination of the environment and the overall exposure of the populations. However they do not always provide an adequate spatial resolution to characterize environmental exposures as they are usually not assembled for this specific purpose. Statistical methods are employed to process input databases (environmental concentrations in water, air and soil) in the objective of characterizing the exposure. A multimedia model interfaced with a GIS, allows the integration of environmental variables in order to yield exposure doses related to ingestion of food, water and soil as well as atmospheric contaminants' inhalation.The methodology was applied to three Polycyclic Aromatic Hydrocarbon substances, (benzo[a]pyrene, benzo[ghi]perylene and indeno[1,2,3-cd]pyrene), in France. The results obtained, allowed to map exposure indicators and to identify areas of overexposure and characterize environmental determinants. In the context of exposure characterization, the direct spatialization of available data from environmental measurement datasets poses a certain number of methodological questions which lead to uncertainties related to the sampling and the spatial and temporal representativeness of data. These could be reduced by acquiring additional data or by constructing predictive variables for the spatial and temporal phenomena considered.Data processing algorithms and calculation of exposure carried out in this work, will be integrated in the French coordinated integrated environment and health platform-PLAINE in order to be applied on other pollutants and prioritize preventative actions

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Morris, Joshua Powell. « Residual Diesel Range Organics and Selected Frothers in Process Waters from Fine Coal Flotation ». Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23174.

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The purpose of this thesis is to examine some of the potential fates of processing reagents in a coal preparation plant. The focus is specifically on petro-diesel (termed "diesel" in this paper), which is used as a collector in the flotation of fine coal. Diesel range organics (DRO) and polyaromatic hydrocarbons (PAHs) are measured in aqueous samples using gas chromatography equipped with either a flame ionization detector (GC-FID) or a mass spectrometer (GC-MS). Samples are subjected to a variety of test conditions in order to understand the behavior of diesel compounds in coal processing streams.
Results show that frother and collector reagents are not likely to partition completely to a single fraction of the process slurry. Further test work has shown that sub-ppm levels of DRO dominated by the water soluble fraction of diesel are expected to be present in process waters; however, PAHs and insoluble DRO may be removed via volatilization and/or degradation. DRO and PAHs are also expected to be desorbed from coal particles when contacted with fresh water. Flotation tests have revealed that low levels of DRO are found in both the concentrate and tailings processing streams with slightly higher concentrations being found in the concentrate stream. From the tests performed in this thesis, it appears as though there is no apparent environmental concern when coal preparation plants are operating under normal conditions.
Master of Science

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Loick, Nadine. « Bioremediation of poly-aromatic hydrocarbon (PAH) contaminated soil by co-composting ». Thesis, Bangor University, 2008. https://research.bangor.ac.uk/portal/en/theses/bioremediation-of-polyaromatic-hydrocarbon-pah-contaminated-soil-by-cocomposting(c9621363-f6c1-438a-a899-f23160ce07c3).html.

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25

Furlan, Bianca [UNESP]. « Biodegradação de naftaleno, fenantreno e diesel por isolados do gênero Burkholderia da Amazônia ». Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/95001.

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O gênero Burkholderia compreende um grupo de bactérias muito diversificado, ocupando vários nichos ecológicos e possui espécies que causam doenças, mas outras espécies apresentam habilidades importantes para os ramos da agricultura, biotecnologia e do ambiente, como a biodegradação. Essas bactérias são morfologicamente semelhantes e o gênero está dividido em dezessete genomovars, onde espécies semelhantes geneticamente são agrupadas, formando o Complexo Burkholderia cepacia (CBC). Por meio de estudos moleculares do gene 16S rRNA e do gene recA foi possível fazer a classificação adequada em espécies dos 450 isolados obtidos da Terra Preta Antropogênica (TPA) e adjacentes, em quatro sítios (TPA Caldeirão Cultivado; TPA Caldeirão Capoeira; TPA Hatahara e TPA Mina-I), foram obtidos 177 isolados do gênero Burkholderia. Desses isolados, pela análise do gene 16S rRNA foi possível classificar 157 isolados ao nível de espécie e pela análise do gene recA somente 105 isolados foram classificados neste mesmo nível. Esses isolados foram utilizados no teste de biodegradação dos hidrocarbonetos. Os hidrocarbonetos poliaromáticos (HPAs) são compostos orgânicos resultantes da combustão incompleta da matéria orgânica e dos derivados de petróleo, são pouco solúveis em água e muito tóxicos para as células, por isso, não são metabolizados por muitos micro-organismos e acabam contaminando e inviabilizando os ambientes. Nos testes de biodegradação os substratos utilizados foram o naftaleno, o fenantreno e o diesel, juntamente com o indicador redox 2,6- diclorofenol-indofenol (DCPIP), que sofre descoloração (de azul para incolor) quando as células utilizam os substratos como fonte de carbono para o crescimento celular, gerando elétrons que vão reduzir o indicador. Pela análise do teste, 19 isolados degradaram o naftaleno, 16 degradaram...
The genus Burkholderia comprises a very diverse group of bacteria occupying various ecological niches and has species that cause disease, but other species have important skills to the branches of agriculture, biotechnology and the environment, as biodegradation. These bacteria are morphologically similar genus and is divided into seventeen genomovars, where genetically similar species are grouped together, forming the Burkholderia cepacia complex (BCC). Through molecular studies of 16S rRNA and recA gene was possible to make the appropriate classification of species in 450 isolates of Terra Preta Antropogênica (TPA) and adjacent at four sites (TPA Caldeirão Cultivado; TPA Caldeirão Capoeira; TPA Hatahara e TPA Mina-I) were obtained 177 isolates of the genus Burkholderia. These isolates by 16S rRNA gene analysis was possible to classify 157 isolates to species level and the recA gene analysis only 105 isolates were classified in the same level. These isolates were used to test the biodegradation of hydrocarbons. Polyaromatic hydrocarbons (PAHs) are organic compounds resulting from incomplete combustion of organic matter and petroleum derivatives, are not very soluble in water and very toxic to cells, therefore, are not metabolized by many microorganisms to contaminate and render environments. In biodegradation tests the substrates used were naphthalene, phenanthrene and the diesel, along with the redox indicator 2,6- dichlorophenol-indophenol (DCPIP), who suffers discoloration (blue to colorless) when cells use the substrates as a source of carbon for cell growth, generating electrons that will reduce the indicator. By analysis of the test, 19 isolates degraded naphthalene, phenanthrene degraded the 16 and 126 degraded diesel, generating a total of 132 isolates of the genus Burkholderia that have the ability to degrade at least... (Complete abstract click eletronic access below)

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Silva, Celyna K?ritas Oliveira da. « Avalia??o do processo oxidativo avan?ado por permanganato de pot?ssio no tratamento de solos contaminados com idrocarbonetos poliarom?ticos ». Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15801.

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The soil contamination with petroleum is one of the major concern of industries operating in the field and also of environmental agencies. The petroleum consists mainly of alkanes and aromatic hydrocarbons. The most common examples of hydrocarbons polyaromatic are: naphthalene, anthracene, phenanthrene, benzopyrene and their various isomers. These substances cause adverse effects on human and the environment. Thus, the main objective of this work is to study the advanced oxidation process using the oxidant potassium permanganate (KMnO4) for remediation of soils contaminated with two polyaromatic hydrocarbons (PAHs): anthracene and phenanthrene. This study was conducted at bench scale, where the first stage was at batch experiment, using the variables: the time and oxidant dosage in the soil. The second stage was the remediation conducted in continous by a fix column, to this stage, the only variable was remediation time. The concentration of oxidant in this stage was based on the best result obtained in the tests at batch, 2,464 mg / L. The results of degradation these contaminants were satisfactory, at the following dosages and time: (a) 5g of oxidant per kg soil for 48 hours, it was obtained residual contaminants 28 mg phenanthrene and 1.25 mg anthracene per kg of soil and (b) for 7g of oxidant per kg soil in 48 hours remaining 24 mg phenanthrene and anthracene 0.77 mg per kg soil, and therefore below the intervention limit residential and industrial proposed by the State Company of Environmental Sao Paulo (CETESB)
A contamina??o de solo com petr?leo ? uma das grandes preocupa??es das ind?strias que atuam no ramo e tamb?m dos ?rg?os ambientais. O petr?leo ? constitu?do basicamente por hidrocarbonetos alcanos e arom?ticos. Os exemplos mais comuns dos hidrocarbonetos poliarom?ticos s?o: naftaleno, antraceno, fenantreno, benzopireno e seus v?rios is?meros. Estas subst?ncias apresentam efeitos nocivos ao ser humano e ao meio ambiente. Logo, este trabalho tem como principal objetivo, estudar o processo de oxida??o avan?ada, utilizando o oxidante permanganato de pot?ssio (KMnO4), na remedia??o de solos contaminados com dois hidrocarbonetos poliarom?ticos (HPAs): antraceno e fenantreno. Este estudo foi realizado em escala de bancada, sendo a primeira etapa realizada experimentos em batelada, utilizando as vari?veis: tempo de remedia??o e dosagem do oxidante. Na segunda etapa, a remedia??o foi realizada em regime cont?nuo utilizando coluna de leito fixo, para esta etapa a ?nica vari?vel foi tempo de remedia??o. A concentra??o do oxidante nesta etapa, foi baseada no melhor resultado obtido nos ensaios em batelada, 2464 mg/L. Os resultados da degrada??o destes contaminantes foram satisfat?rios, nas seguintes dosagens de oxidante e tempo de remedia??o: (a) 5g de oxidante por kg de solo em 48 horas, foram obtidos contaminantes residuais de 28 mg de fenantreno e 1,25 mg de antraceno por kg de solo e (b) para 7g de oxidante por kg de solo em 48 horas restaram 24 mg de fenantreno e 0,77 mg de antraceno por kg de solo, ficando abaixo dos valores de interven??o residencial e industrial propostos pela Companhia Ambiental do Estado de S?o Paulo (CETESB)

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Lindborg, Marcus. « GC-MS analysis for Polyaromatic Hydrocarbons (PAH) in Moroccan medicinal tars : An ethnobotanical study and chemical investigation of the use and safety of medicinal tars in Marrakesh and the High Atlas Mountains, Morocco ». Thesis, Uppsala universitet, Systematisk biologi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-141819.

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28

Stewart, Shona Diane. « Surface enhanced Raman scattering on electrochemically prepared silver surfaces ». Thesis, Queensland University of Technology, 1999.

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29

Cupák, Petr. « STUDIUM BIOGENNÍCH POJIV ». Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-233964.

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oundry production, which forms an integral part of the engineering industry, is a source of waste with a negative impact on the working and living environment. The pressure on greening the production in all production branches of industry does not dodge the foundry industry and technical engineers seek out possibilities of decreasing the negative impact of the production of casting on the environment. An important source of environmentally dangerous waste in foundry operation is the use of organic compounds during the preparation of shaping and core mixtures. Their substitution with materials that would ensure similar technological features of the shaping and core mixtures as the organic materials used hitherto and at the same time decrease the amount of solid, liquid and gaseous ecologically undesirable compounds used in or arising during the preparation and use of shaping and core mixtures, would be significant for decreasing the ecological burden connected to casting production. A promising group of materials usable as components of shaping and core mixtures are the biopolymer materials which can substitute the organic connective systems used in the production of foundry cores by the means of the so-called hot processes – Hot-Box and Warm-Box. This work focuses on the exploration of the technological and ecological features of several biopolymer materials available on the domestic market which have the potential to become a full alternative of the binders used so far on the basis of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and furan resins.

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Benigni, Paolo. « Trapped Ion Mobility Spectrometry coupled to Fourier Transform Ion Cyclotron Resonance Mass Spectrometry for the analysis of Complex Mixtures ». FIU Digital Commons, 2017. https://digitalcommons.fiu.edu/etd/3547.

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Analytical Characterization of complex mixtures, such as crude oil, environmental samples, and biological mixtures, is challenging because of the large diversity of molecular components. Mass spectrometry based techniques are among the most powerful tools for the separation of molecules based on their molecular composition, and the coupling of ion mobility spectrometry has enabled the separation and structural elucidation using the tridimensional structure of the molecule. The present work expands the ability of analytical chemists by furthering the development of IMS-MS instrumentation by coupling Trapped Ion Mobility Spectrometry to Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (TIMS-FT-ICR MS). The TIMS-FT-ICR MS platform combines the high-resolution separation of TIMS, which has mobility resolving powers up to 400, and ultra-high mass resolution of FT-ICR MS, with mass resolving power over 1,000,000. This instrumentation allows the assignment of exact chemical composition for compounds in a complex mixture, as well as measurement of the collision cross-section of the molecule. Herein, the principles of the TIMS separation and its coupling to FT-ICR MS are described, as well as how the platform can be applied to targeted analysis of molecules, and untargeted characterization of complex mixtures. Molecular standards were analyzed by TIMS-MS in order to develop a computational workflow that can be utilized to elucidate molecular structure, using the measured collision cross-section of the ion. This workflow enabled identification of structural, cis/trans isomers, and chelated molecules and provides the basis for unsupervised structural elucidation of a complex mixture, and in particular for the elucidation of hydrocarbons from fossil fuels. In summary, this work presents the coupling of TIMS-FT-ICR MS and provides examples of applications as a proof of concept of the potential of this platform for solving complex analytical challenges.

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Mailu, Stephen Nzioki. « Development of electrochemical sensors containing bimerallic silver and gold nanoparticles ». Thesis, University of the Western Cape, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_7576_1305534870.

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In this work, a simple, less time consuming electrochemical method in the form of an electrochemical sensor has been developed for the detection of PAHs. The sensor was fabricated by the deposition of silver-gold (1:3) alloy nanoparticles (Ag-AuNPs) on ultrathin overoxidized polypyrrole (PPyox) film which formed a PPyox/Ag-AuNPs composite on glassy carbon electrode (PPyox/Ag-AuNPs/GCE). The silver-gold alloy nanoparticles deposited to form the composite were chemically prepared by simultaneous reduction of silver nitrate (AgNO3) and chloroauric acid (HAuCl4) using sodium citrate and characterized by UV-visible spectroscopy technique which confirmed the homogeneous formation of the alloy nanoparticles.

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Левчук, Ірина Володимирівна. « Науково-методологічні основи удосконалення технохімічного контролю сировини і готової продукції олійножирових виробництв ». Thesis, Національний технічний університет "Харківський політехнічний інститут", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/39036.

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Дисертація на здобуття наукового ступеню доктора технічних наук за спеціальністю 05.18.06 − технологія жирів, ефірних масел і парфумерно-косметичних продуктів – Національний технічний університет "Харківський політехнічний інститут" Міністерства освіти і науки України, Харків, 2018 р. Дисертаційну роботу присвячено науковому обґрунтуванню застосування системного комплексного підходу щодо створення сучасних схем технохімічного контролю сировини і готової продукції олійножирових виробництв з використанням виключно інструментальних методів аналізу: газорідинної хроматографії, високоефективної рідинної хроматографії, газової хромато-масспектроскопії, зонального капілярного електрофорезу та ін. На основі узагальнення теоретичних і експериментальних даних розроблено схему забруднення олійного насіння, соняшникової олії та олієжировмісних продуктів природними та антропогенними екотоксикантами: пестицидами, поліхлорованими біфенілами, поліароматичними вуглеводнями, фталатами, сторонніми домішками органічного і неорганічного походження, харчовими добавками. Удосконалено стандартизований метод визначення воскоподібних речовин. Експериментально досліджено розподіл пестицидів різних класів у насінні соняшнику і продуктах його переробки. Розроблено науково обґрунтовані способи визначення пестицидів, в т.ч. за умови їх сумісної присутності. Гармонізовано з міжнародними вимогами спосіб визначення поліароматичних вуглеводнів (ПАВ) і встановлено, що вміст бенз(а)пірену є технологічним маркером по відношенню до суми ПАВ. Розроблено пріоритетний спосіб визначення фталатів, що мігрують з ПЕТ-упаковки у рослинні олії та жировмісні продукти. Теоретично та експериментально обгрунтовано необхідність застосування методів визначення жирнокислотного, ацилгліцерольного (в т.ч. індивідуального) та складу стеролової фракції для ідентифікації олій та жирів, зокрема для виявлення сторонніх домішок мінерального (мінеральних олив) та органічного (нехарчового курячого жиру) походження, тобто для цілей фальсифікації. Створено наукове та методологічне підґрунтя щодо створення національного стандарту щодо контролювання вмісту консервантів у жировмісних продуктах. Розроблено практичні рекомендації щодо удосконалення схем технохімконтролю сировини і готової продукції у виробництві соняшникової олії, в т.ч. фасованої в полімерну тару, маргаринової продукції, майонезу та салатних соусів, купажованих олій.
Thesis for the Doctor's of Engineering by specialty 05.18.06 − technology of fats, essential oils and perfumery and cosmetic products. − National Technical University "Kharkiv Polytechnic Institute" of the Ministry of Education and Science of Ukraine, Kharkiv, 2018. The thesis is devoted to the scientific substantiation of the application of the system complex approach to the creation of modern schemes of techno-chemical control of raw materials and finished products of fat-and-oil production with the use of exclusively instrumental methods of analysis: gas-liquid chromatography, high-performance liquid chromatography, gas chromatography, zonal capillary electrophoresis, etc. It has been developed the scheme on the basis of theoretical and experimental data generalization of oilseed, sunflower oil and oily products contamination by natural and anthropogenic ecotoxicants, namely pesticides, polychlorinated biphenyls, polyaromatic hydrocarbons, phthalates, foreign impurities of organic and inorganic origin, and food additives. The standardized method of determining wax-like substances has been improved. The distribution of pesticides of various classes in sunflower seed and products of its processing has been experimentally investigated. Scientifically grounded methods of pesticide determination have been developed including their simultaneous presence. A priority method for determination of migrating phthalates from PET packaging in vegetable oils and fat-containing products has been developed. The necessity of using methods for determining the fatty acid, acylglycerol (including individual) and composition of the sterol fraction for the identification of oils and fats, in particular for the foreign impurities detection of mineral (mineral oils) and organic (nonfood chicken fat) origin, i.e. for goals of falsification, has been grounded scientifically and theoretically. A scientific and methodological basis for establishing a national standard for controlling the content of preservatives in fatty products has been created. Practical recommendations for improving the schemes of technochemical control of raw materials and finished products in the sunflower oil production, including packed in plastic containers, margarine products, mayonnaise, salad dressings and blended oils have been developed.

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Левчук, Ірина Володимирівна. « Науково-методологічні основи удосконалення технохімічного контролю сировини і готової продукції олійножирових виробництв ». Thesis, Національний технічний університет "Харківський політехнічний інститут", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/39037.

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Дисертація на здобуття наукового ступеню доктора технічних наук за спеціальністю 05.18.06 − технологія жирів, ефірних масел і парфумерно-косметичних продуктів – Національний технічний університет "Харківський політехнічний інститут" Міністерства освіти і науки України, Харків, 2018 р. Дисертаційну роботу присвячено науковому обґрунтуванню застосування системного комплексного підходу щодо створення сучасних схем технохімічного контролю сировини і готової продукції олійножирових виробництв з використанням виключно інструментальних методів аналізу: газорідинної хроматографії, високоефективної рідинної хроматографії, газової хромато-масспектроскопії, зонального капілярного електрофорезу та ін. На основі узагальнення теоретичних і експериментальних даних розроблено схему забруднення олійного насіння, соняшникової олії та олієжировмісних продуктів природними та антропогенними екотоксикантами: пестицидами, поліхлорованими біфенілами, поліароматичними вуглеводнями, фталатами, сторонніми домішками органічного і неорганічного походження, харчовими добавками. Удосконалено стандартизований метод визначення воскоподібних речовин. Експериментально досліджено розподіл пестицидів різних класів у насінні соняшнику і продуктах його переробки. Розроблено науково обґрунтовані способи визначення пестицидів, в т.ч. за умови їх сумісної присутності. Гармонізовано з міжнародними вимогами спосіб визначення поліароматичних вуглеводнів (ПАВ) і встановлено, що вміст бенз(а)пірену є технологічним маркером по відношенню до суми ПАВ. Розроблено пріоритетний спосіб визначення фталатів, що мігрують з ПЕТ-упаковки у рослинні олії та жировмісні продукти. Теоретично та експериментально обгрунтовано необхідність застосування методів визначення жирнокислотного, ацилгліцерольного (в т.ч. індивідуального) та складу стеролової фракції для ідентифікації олій та жирів, зокрема для виявлення сторонніх домішок мінерального (мінеральних олив) та органічного (нехарчового курячого жиру) походження, тобто для цілей фальсифікації. Створено наукове та методологічне підґрунтя щодо створення національного стандарту щодо контролювання вмісту консервантів у жировмісних продуктах. Розроблено практичні рекомендації щодо удосконалення схем технохімконтролю сировини і готової продукції у виробництві соняшникової олії, в т.ч. фасованої в полімерну тару, маргаринової продукції, майонезу та салатних соусів, купажованих олій.
Thesis for the Doctor's of Engineering by specialty 05.18.06 − technology of fats, essential oils and perfumery and cosmetic products. − National Technical University "Kharkiv Polytechnic Institute" of the Ministry of Education and Science of Ukraine, Kharkiv, 2018. The thesis is devoted to the scientific substantiation of the application of the system complex approach to the creation of modern schemes of techno-chemical control of raw materials and finished products of fat-and-oil production with the use of exclusively instrumental methods of analysis: gas-liquid chromatography, high-performance liquid chromatography, gas chromatography, zonal capillary electrophoresis, etc. It has been developed the scheme on the basis of theoretical and experimental data generalization of oilseed, sunflower oil and oily products contamination by natural and anthropogenic ecotoxicants, namely pesticides, polychlorinated biphenyls, polyaromatic hydrocarbons, phthalates, foreign impurities of organic and inorganic origin, and food additives. The standardized method of determining wax-like substances has been improved. The distribution of pesticides of various classes in sunflower seed and products of its processing has been experimentally investigated. Scientifically grounded methods of pesticide determination have been developed including their simultaneous presence. A priority method for determination of migrating phthalates from PET packaging in vegetable oils and fat-containing products has been developed. The necessity of using methods for determining the fatty acid, acylglycerol (including individual) and composition of the sterol fraction for the identification of oils and fats, in particular for the foreign impurities detection of mineral (mineral oils) and organic (nonfood chicken fat) origin, i.e. for goals of falsification, has been grounded scientifically and theoretically. A scientific and methodological basis for establishing a national standard for controlling the content of preservatives in fatty products has been created. Practical recommendations for improving the schemes of technochemical control of raw materials and finished products in the sunflower oil production, including packed in plastic containers, margarine products, mayonnaise, salad dressings and blended oils have been developed.

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Šubrt, Michal. « Stanovení derivátů polycyklických aromatických uhlovodíků v životním prostředí ». Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2013. http://www.nusl.cz/ntk/nusl-216946.

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Le, Maître Johann. « Développement de la spectrométrie de masse à ultra- haute résolution associée à la spectrométrie de mobilité ionique pour la caractérisation de coupes pétrolières lourdes. structural analysis of heavy oil fractions afterr hydrodenitrogenation by high-resolution tandem mass spectrometry and ion mobility spectrometry Structural analysis of neutral nitrogen compounds refractory to the hydrodenitrogenation process of heavy oil fractions by high-resolution tandem mass spectrometry and ion mobility-mass spectrometry Chemical characterization of 15 biocrudes obtained from hydrothermal liquefaction of industrially cultivated wild micro algae Chemical characterization with different analytical techniques, a way to understand the process : Case of the paraffinic base oil production line Exploring complex mixtures by cyclic ion mobility high-resolution mass spectrometry – Application towards Petroleum. Simulation and modeling of Collision Cross Section for structural elucidation of heavy oil fraction by ion mobility-mass spectrometry : Using polyaromatic hydrocarbons compounds mixture as calibration standard Characterization of sulfoxides compounds in dimeric distribution of heavy oil fractions by positive-ion electrospray ionization FTICR mass spectrometry Structural analysis of Petroporphyrins from asphaltene by trapped ion mobility coupled with a Fourier transform ion cyclotron resonance mass spectrometer. Cyclic ion mobility spectrometry coupled to high-resolution time-of-flight mass spectrometry equipped with atmospheric solid analysis probe for the molecular characterization of combustion particulate matter. Structural study of analogues of Titan’s haze by trapped ion mobility coupled with a Fourier transform ion cyclotron mass spectrometer ». Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR051.

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L'évolution des réserves de pétrole implique l'utilisation en raffinerie de pétroles bruts non conventionnels, bien souvent plus lourds et donc difficiles à caractériser. Les produits pétroliers sont en effet des mélanges chimiques extrêmement complexes. La partie légère et volatile peut être analysée par chromatographie en phase gazeuse couplée à la spectrométrie de masse (GC/MS), permettant l'identification des composés par l'utilisation de mesures de masses précises et de modèles de fragmentation. Cependant ces techniques sont inadaptées à l'analyse des fractions lourdes. Dans la pratique, la caractérisation des mélanges les plus complexes implique l'utilisation de spectromètres de masse à ultra-haute résolution généralement par analyse directe sans séparation chromatographique. La technique de référence est aujourd’hui la spectrométrie de masse à transformée de Fourier par résonance cyclotronique des ions (FTICR). Grâce à une résolution supérieure à 106 et à une précision de mesure de masse inférieure à 0,1 ppm, cet instrument permet de séparer toutes les espèces présentes dans un produit pétrolier et d'attribuer à chaque valeur de m/z une composition élémentaire unique. Ceci permet d'obtenir très facilement des cartes moléculaires qui peuvent être présentées graphiquement en utilisant le diagramme de Kendrick, le diagramme de van Krevelen ou le nombre d'insaturations (DBE) en fonction du nombre de carbones. Ce travail de thèse a permis grâce à la caractérisation moléculaire de produits pétroliers (Vacuum Gas Oil, Pétroles Bruts, Matériel Interfacial, Asphaltènes et Bio-Oil…) d'aborder la complexité de leur traitement dans l’outil de raffinage. Des protocoles d'analyses des échantillons ont été développés, à l'aide de différentes sources d'ionisation à pression atmosphérique (ESI, APCI et APPI) ainsi que par désorption/ionisation laser (LDI) sur le spectromètre de masse FTICR 12T. Les informations sur le contenu isomérique des produits pétroliers ont ensuite été déterminées grâce à l'apport de la spectrométrie de mobilité ionique (IMS)
The evolution of oil reserves requires the use in refineries of unconventional crude oils, which are often heavier and therefore difficult to characterize. Petroleum products are in fact extremely complex chemical mixtures. The light and volatile part can be analysed by gas chromatography coupled with mass spectrometry (GC/MS), allowing the identification of compounds by using precise mass measurements and fragmentation models. However, these techniques are inappropriate for the analysis of heavy fractions. In practice, the characterization of the most complex mixtures involves the use of ultra-high-resolution mass spectrometers generally by direct analysis without chromatographic separation. The reference technique today is Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FTICR). With a resolution of more than 106 and a mass measurement accuracy of less than 0.1 ppm, this instrument can separate all the species present in a petroleum product and assign a unique elemental composition to each m/z value. This makes it very easy to obtain molecular maps that can be presented graphically using the Kendrick diagram, the van Krevelen diagram or the number of unsaturations (DBE) as a function of the number of carbons. This thesis work has allowed thanks to the molecular characterization of petroleum products (Vacuum Gas Oil, Crude Oil, Interfacial Material, Asphaltenes and Bio-Oil...) addressing the complexity of their treatment in the refining tool. Protocols for sample analysis have been developed, using different sources of ionization at atmospheric pressure (ESI, APCI and APPI) as well as laser desorption/ionization (LDI) on the FTICR 12T mass spectrometer. Information on the isomeric content of petroleum products was then determined using ion mobility spectrometry (IMS)

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SEYED, KHOEI NAZANINALSADAT. « Study of the biogenic potential of nanoparticle formation from selenite and tellurite by two environmental strains of Burkholderia fungorum and assessment of their resistance as planktonic cells or biofilms to polyaromatic hydrocarbons ». Doctoral thesis, 2016. http://hdl.handle.net/11562/940778.

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Qui riportiamo due ceppi di Burkholderia Fungorum (DBT1 e 95) e la loro capacità sia in modalità planctonici e biofilm resistere elevate concentrazioni di idrocarburi per essere utilizzata nei protocolli di biorisanamento. B. Fungorum DBT1 stato isolato da drenaggio raffineria di petrolio, mentre B. Fungorum 95 è stato isolato dai tessuti interni di una pianta pioppo ibrido coltivata in terreno contaminato da idrocarburi aromatici policiclici (IPA). Gli idrocarburi testati sono stati dibenzotiofene (DBT) come campione di tiofeni ed una miscela di IPA, e cioè: naftalene, fenantrene e pirene. Inoltre, la loro capacità di trasformare ossianioni metalloidi tossici (selenite e telluriti) a forma elementare non tossica è stata valutata. Questa trasformazione non solo sradicare i composti metalloidi tossici nella zona contaminata, ma può anche essere utilizzato per ottenere forma elementare del metalloide in forma di nanoparticelle con applicazioni in tecnologia e della medicina. I nostri risultati hanno dimostrato che entrambi i ceppi degradate alta concentrazione di dibenzotiofene e entrambe le forme di biofilm e planctonici di batteri resistito fino a 2000 mg l-1 di questo composto. Inoltre, B. Fungorum DBT1 ha mostrato riduzione della tolleranza agli IPA miscela (naftalene 2000 mg l-1, fenantrene 800 mg l-1 e pirene 400 mg l-1) come biofilm e forme planctoniche. Al contrario, la formazione di biofilm aiutato B. Fungorum 95 per resistere IPA a queste concentrazioni, mentre forma planctoniche non poteva resistere. Infatti, alta concentrazione di DBT causato la formazione di aggregazione biofilm. D'altra parte, ceppo DBT1 era in grado di ridurre 0,5 mM selenite e 0,1 mM tellurite, mentre ceppo 95 ridotta più di 1 mM selenite e 0,05 mM Tellurite a forme elementari entro 96 ore di incubazione aerobica. B. Fungorum 95 prodotti 1 mM di selenio in presenza di 2 mM selenite. nanoparticelle prodotte selenio erano sferica e lo zero accusati di diametro medio idrodinamica di 170 nm (per il ceppo 95) e 200 nm (per ceppo DBT1). Tuttavia, le nanoparticelle prodotte tellurio erano ago come e positivo accusato di diametro medio idrodinamica di 120 nm e 170 nm per i ceppi 95 e DBT1 rispettivamente. La scansione e la microscopia elettronica a trasmissione analisi hanno mostrato entrambe le nanoparticelle selenio extracellulari e intracellulari. Selenite test di attività riduzione evidenziato attivazione enzimatica citoplasmatica accettando elettrone da donatori di elettroni. Dal momento che le nanoparticelle sono verificati extracellulare ma sono prodotti all'interno delle cellule in base al test di attività riduzione selenite, sia in uscita dalla secrezione o dopo la lisi cellulare. Tuttavia, le nanoparticelle di tellurio sono prodotti e si sono verificati intracellulare dalle attività citoplasmatica. In conclusione, i risultati per la resistenza contro idrocarburi forniscono nuove prospettive sulla efficienza di utilizzo di ceppi batterici DBT-degradanti in biorisanamento dei siti contaminati che contengono un'alta concentrazione di idrocarburi aromatici poli e tiofeni e bassa concentrazione di ossianioni metalloidi di selenio e tellurio. Produzione di nanoparticelle di selenio e tellurio in condizioni aerobiche da ceppi DBT1 e 95 potrebbe essere dovuto a meccanismi di riduzione intracellulari. Queste nanoparticelle biogene di entrambi i tipi presenti dimensioni compatibili con le applicazioni mediche e tecnologiche che sono attualmente in fase di studio.
Here we report on two strains of Burkholderia fungorum (DBT1 and 95) and their ability in both planktonic and biofilm modes to resist high concentrations of hydrocarbons in order to be exploited in bioremediation protocols. In nature, bacteria often attach to surfaces by establishing biofilms. B. fungorum DBT1 was isolated from an oil refinery drainage, while B. fungorum 95 was isolated from the inner tissues of a hybrid poplar plant cultivated in a soil contaminated by polycyclic aromatic hydrocarbons (PAHs). The hydrocarbons tested were dibenzothiophene (DBT) as a sample of thiophenes and a mixture of PAHs, namely: naphthalene, phenanthrene and pyrene. Moreover, their ability to transform toxic metalloid oxyanions (namely selenite and tellurite) to non-toxic elemental form was evaluated. This transformation not only eradicate the toxic metalloid compounds in contaminated area, but also can be utilized in order to obtain elemental form of metalloid in the form of nanoparticles with applications in technology and medicine. Our results showed that both strains degraded high concentration of dibenzothiophene and both forms of biofilm and planktonic of bacteria resisted up to 2000 mg l-1 of this compound. Moreover, B. fungorum DBT1 showed reduction in tolerance to PAHs mixture (naphthalene 2000 mg l-1, phenanthrene 800 mg l-1 and pyrene 400 mg l-1) as biofilm and planktonic forms. In contrary, formation of biofilm helped B. fungorum 95 to resist PAHs in these concentrations while planktonic form could not resist. Confocal laser scanning microscopy pictures showed that by exposing biofilm to DBT and PAHs, the structure changes. In fact, high concentration of DBT caused the formation of aggregation in biofilm. On the other hand, the result of both strains behavior in the presence of metalloids showed that strain DBT1 was able to reduce 0.5 mM selenite and 0.1 mM tellurite, while strain 95 reduced more than 1 mM selenite and 0.05 mM tellurite to elemental forms within 96 hours of aerobic incubation. B. fungorum 95 produced 1 mM selenium in the presence of 2 mM selenite. Produced selenium nanoparticles were spherical and zero charged with average hydrodynamic diameter of 170 nm (for strain 95) and 200 nm (for strain DBT1). However, produced tellurium nanoparticles were needle like and positive charged with average hydrodynamic diameter of 120 nm and 170 nm for strains 95 and DBT1 respectively. Scanning and transmission electron microscopy analyses showed both extracellular and intracellular selenium nanoparticles. Selenite reduction activity test evidenced cytoplasmic enzymatic activation by accepting electron from electron donors. Since nanoparticles occurred extracellularly but they are produced intracellularly according to selenite reduction activity test, either they exit by secretion or after cell lysis. However, tellurium nanoparticles are produced and occurred intracellularly by cytoplasmic activity. In conclusion, the findings for the resistance against hydrocarbons provide new perspectives on the efficiency of using DBT-degrading bacterial strains in bioremediation of contaminated sites containing high concentration of poly aromatic hydrocarbons and thiophenes and low concentration of metalloid oxyanions of selenium and tellurium. Production of selenium and tellurium nanoparticles under aerobic conditions by strains DBT1 and 95 could be due to intracellular reduction mechanisms. These biogenic nanoparticles of both kinds present size compatible with medical and technological applications which are currently under study.

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Chen, Tse-An, et 陳則安. « Synthesis and Characterization of New Polyaromatic Hydrocarbons (PAHs) ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/81072117322150886702.

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博士
國立清華大學
化學系
100
Chapter I： We reported regiocontrolled syntheses of ethene-bridged para-phenylene oligomers in three distinct classes using Pt(II)- and Ru(II)-catalyzed aromatization. This synthetic approach is developed based on two-fold aromatization of 1-aryl-2-alkynylbenzene functionality, which proceeds via distinct regioselectivity for platinum and ruthenium catalysts. Variable-temperature NMR spectra provide evidence that large arrays of these oligomers are prone to twist from planarity. The ultra violet (UV), photoluminescence (PL) and band gaps of these regularly growing arrays show a pattern of extensive π-conjugation with increasing array sizes except for one instance. Chapter II： Part 1：A facile synthesis of three series cata-condensed polyaromatic hydrocarbons, initial ICl-promoted cyclization of bis(biaryl)acetylenes, followed by the Mizoroki-Heck coupling reaction has been reported. This approach works well for various bis(biaryl)acetylenes to afford dibenzo[g,p]chrysenes as core structure and extended the conjugated benzene ring from different direction. The photophysical and electronic properties of these highly twist cata-ondensed polyaromatic hydrocarbons has affected by aromaticity and the position of new extended conjugated benzene ring. Part 2：We also demonstrated Pt(II)- and Ru(II)-catalyzed cyclization of 1,3,5-(tri-4-tert-butylbenzene)-2,4,6-triethynylbenzene to synthesis new cata-ondensed polyaromatic hydrocarbons. Chapter III： Part 1：A new synthesis of large PAHs with low Clar sextets was developed. Dibenzochrysene derivatives can be transformed into planar polyaromatic hydrocarbons by using DDQ-oxidation reaction. The photophysical and electronic properties of these compound including UV/Vis, photoluminscence and cyclic voltammetry indicate that these properties are greatly affected by the increasing array size. Part 2：We have developed a new synthesis of large-sized PAHs with low Clar sextets. This two-step synthesis involves starting bis(biaryl)diynes, which undergo initial PtCl2-catalyzed aromatizations, and subsequent DDQ-oxidation. The resulting PAH products have aromatic characters on the outer benzenes and polyene properties on indicates an efficient electron-delocalization within the frameworks of these PAHs. This convenient approach is applicable to a large PAH that has small energy gap (2.07 eV). Chapter IV： The last chapter study for interior aromatic addition chemistry on planar dibenzo[de, op]bisanthracene (DBBA), unfortunately we didn’t find any evidence for addition chemistry on interior carbon, but still find some interesting reaction bear high regioselectivity on DBBA compound, such as Friedal-craft reaction, nucleophilic addition, epoxidation and new type intermolecular Scholl reaction.

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Vipotnik, Ziva. « Bioremediation and biodegradation of selected polyaromatic hydrocarbons by fungi ». Doctoral thesis, 2021. http://hdl.handle.net/1822/75428.

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Tese de doutoramento em Engenharia Química e Biológica
Despite the amount of pollutants in the ecosphere has been increasing for a long time, soil contaminated with polyaromatic hydrocarbons (PAH) still remains one of the most important environmental problems worldwide. PAH are universal pollutants with a big variation in their concentration levels in different regions. PAH tend to bind to clays as these have high surface area, which allows more binding and adsorption of PAH on finer soil fractions. However, clay particles reduce in size as time goes by, diminishing porosity and transferable species in soil, and with aging of PAH also lose bioavailability, becoming persistent. Despite the different reported bioremediation techniques, this work focus on the biological degradation of PAH with fungi and their enzymes, mainly laccase and laccase-mediator systems. Laccases are receiving attention from different researchers due to their specific nature. They may be used in different industrial applications as they present the ability to oxidize a broad spectrum of phenolic and nonphenolic compounds. Moreover, processes with laccases are quite competitive with conventional chemical processes in different industries. However, the main limiting factor to their application still remains – large-scale production of laccase, mainly of highly active and stable laccase, is still to be attained. The work is globally divided into two parts, depending on the soil used: artificially contaminated or naturally contaminated soils. In the first part of this work the effect of soil pH and of different supports was evaluated, and the enzyme activities during the PAH degradation in soil were measured. Moreover, laccase degradation was set up, produced by fungal co- cultivation, using kiwi peels as substrate. The produced laccase was applied to PAH contaminated soil to evaluate its efficiency on enzymatic bioremediation. In a second part, heavily PAH and metals polluted soil obtained from Lagos, Nigeria, was used. Trametes versicolor was isolated from this soil and used in degradation experiments, with plantain peels as support. Laccase degradation assays were also set up, in batch and in PBR, with and without mediators. The mediators used were ferulic acid, coumaric acid and ABTS. It was observed that mediators as ABTS and ferulic acid were more successful enhancing PAH degradation.
Apesar da crescente poluição da ecosfera que se verifica desde há muito tempo, a contaminação dos solos com hidrocarbonetos poliaromáticos (PAH) mantem-se como um importante problema ambiental a nível mundial. Os PAH são poluentes universais com uma enorme variação dos seus níveis de concentração em diferentes regiões. Os PAH tendem a ligar-se a argilas graças à elevada área superficial destas últimas, favorecendo a sua ligação e adsorção em frações mais finas de solo. No entanto, com a passagem do tempo e os efeitos de erosão, as partículas de argila vão diminuindo de tamanho, reduzindo a porosidade e a transferência de espécies no solo, assim como os PAH vão perdendo biodisponibilidade, tornando-se mais persistentes. Apesar de diferentes técnicas de biorremediação já terem sido publicadas e exploradas, este trabalho foca-se na degradação biológica de PAH com fungos e suas enzimas, em especial com lacases e sistemas lacases-mediadores. As lacases têm recebido especial atenção por parte dos investigadores graças à sua natureza específica. Elas podem ser usadas em diferentes aplicações industriais já que têm a capacidade de oxidar um largo espetro de compostos fenólicos e não fenólicos. Além disso, processos que usam lacases são bastante competitivos com processos químicos convencionais usados em indústrias distintas. No entanto, o principal fator limitante da sua aplicação ainda permanece – a produção de lacase em larga escala, sobretudo de lacase de elevadas atividade e estabilidade, ainda não foi conseguida Este trabalho está dividido em duas partes gerais, dependendo do solo usado: solo artificialmente contaminado ou solo naturalmente contaminado. Na primeira parte deste manuscrito, o efeito do pH do solo e de diferentes suportes foi avaliado, assim como foram medidas as atividades enzimáticas durante a degradação de PAH no solo. A degradação por lacase foi avaliada por co-cultivo de fungos em substrato de cascas de kiwi. A lacase produzida foi aplicada em solo contaminado por PAH para avaliação da eficiência da biorremediação enzimática. Na segunda parte do trabalho usou-se um solo muito poluído em PAH e metais, obtido em Lagos, na Nigéria. A partir desse solo, isolou-se o Trametes versicolor que foi usado nos ensaios de degradação, com cascas de banana como suporte. Realizaram-se ensaios em batch e em contínuo de degradação de lacase, sem e com mediadores. Os mediadores usados foram o ácido ferúlico, o ácido cumárico e o ABTS. Observou-se que os mediadores ABTS e ácido ferúlico implementam com mais sucesso a degradação dos PAH.
This thesis was financially supported by grant NORTE-69- 2015-15, by Doctoral Program in Applied and Environmental Microbiology (DP_AEM); operation NORTE-08-5369-FSE- 000060; co-financed by North 2020 through the European Social Fund (ESF).

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Ferrari, Diana Noemi Guillen. « Assessment of compost for bioremediation of polyaromatic hydrocarbon (pah) and petroleum hydrocarbon soils ». Master's thesis, 2017. http://hdl.handle.net/10400.1/10159.

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Dissertação de mestrado, Inovação Química e Regulamentação (Erasmus Mundus), Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2017
Bioremediation of petroleum and polyaromatic hydrocarbon (PAH) contaminated soils can be a cost effective and efficient treatment approach. The introduction of organic amendments which can provide available nitrogen, and potentially additional microorganisms, can contribute to improve the biodegradation process. However, little work has considered which organic amendments are best in terms of their relative abundance of degraders for specific pollutants. In this work, green waste (GW) composts of different stability were assessed for their bioremediation potential. Twelve compost samples were characterised for parameters including stability (using a modified set up validated in this project), culturable microbial Pseudomonas and Actinomycetes plate counts and degradative gene (alkB, PAH-RHD GP and PAH-RHD GN) abundance. These are important for the degradation of alkanes and PAH respectively. Comparing finished and un-finished green compost from the same site, results showed that the abundance of alkB (encoding alkane monooxygenase) was highest in the less stable compost samples, which corresponds with the higher Pseudomonas counts. Similar results were obtained for PAH-RHD GN (encoding Polycyclic Aromatic Hydrocarbon-Ring Hydroxylating Dioxygenase in Gram negative bacteria), the less stable samples presented higher abundance of degrading genes. For PAH-RHD GP (encoding Polycyclic Aromatic Hydrocarbon-Ring Hydroxylating Dioxygenase in Gram positive bacteria) abundance, it was not possible to see a clear difference between finished and un-finished samples. Given that less stable composts tend to have higher available N this would support the use of these composts for bioremediation of aliphatic petroleum hydrocarbon and Poly aromatic hydrocarbon contaminated soils.
A biorremediação dos solos contaminados com hidrocarbonetos de petróleo e hidro carboneto poli aromático (HAP) pode ser uma abordagem de tratamento econômica e eficiente. A introdução de emendas orgânicas que podem fornecer nitrogênio disponível e a potencial adicion de microorganismos pode contribuir para melhorar o processo de biodegradação. No entanto, pouco trabalho considerou quais emendas orgânicas são melhores em termos de sua abundância relativa de degradadores para poluentes específicos. Neste trabalho, os compostos de resíduos verdes (GW) de diferentes estabilidades foram avaliados pelo potencial de biorremediação. Doze amostras de compostagem foram caracterizadas por parâmetros incluindo estabilidade (usando uma configuração modificada validada neste projeto), contagens de placas de Pseudomonas e Actinomicetos cultiváveis e abundância degradativa de gene (alkB, PAH-RHD GP e PAH-RHD GN). Estes são importantes para a degradação de alcanos e PAH, respectivamente. Comparando os compostos de residuos verdes acabado e não acabado do mesmo site, os resultados mostraram que a abundância de alk B (codificando alcano monoxigenase) foi maior nas amostras de compostagem menos estáveis, o que corresponde à maior contagem de Pseudomonas. Resultados semelhantes foram obtidos para o PAH-RHD GN (que codifica a Dioxigenase Hidroxilante de hidrocarbonetos aromáticos poliaromáticos em bactérias Gram negativas), as amostras menos estáveis apresentaram maior abundância de genes degradantes. Para PAH-RHD GP (codificando a Dioxigenase Hidroxilante de hidrocarbonetos aromáticos poliaromáticos em bactérias Gram positivas), não foi possível ver uma diferença clara entre amostras acabadas e não acabadas. Dado que os composts menos estáveis tendem a ter maior Nitrogenio disponível, isso apoiaria o uso desses compostos para a biorremediação de solos contaminados com hidrocarbonetos de petróleo alifáticos e com hidrocarbonetos poli aromáticos.

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Tovide, Oluwakemi Omotunde. « Graphenated polyaniline nanocomposite for the determination of polyaromatic hydrocarbons (pahs) in water ». 2013. http://hdl.handle.net/11394/3851.

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Philosophiae Doctor - PhD
The thesis presents a simple, sensitive, low cost and a novel graphenated polyaniline doped tungsten trioxide nanocomposite, as an electrochemical sensor for the detection and quantitative and determination of PAHs, which are ubiquitous, toxic, as well as dangerous organic pollutant compounds in the environment. The selected PAHs (anthracene, phenanthrene and pyrene) in wastewater were given priority as a result of their threat to human nature and that of the environment. In order for a healthy, non-polluted and well sustainable environment, there is need for an instrument that is capable of detecting and quantifying these organic pollutants onsite and also for constant monitoring. The nanocomposites were developed by chemical and electrochemical methods of preparations, exploiting the intrinsic properties of polyaniline, graphene and tungsten trioxide semiconducting materials. Chemically, graphene-polyaniline (GR-PANI) nanocomposite was synthesised by in situ polymerisation method, then casted on a surface of glassy carbon electrode to form GR-PANI modified electrode. The properties of the prepared electrode were investigated through morphological and spectroscopic techniques, which confirmed the formation of the composite. The electroactivity of the prepared modified electrode revealed great improvement in cyclic and square wave voltammetric response on anthracene. A dynamic range of 2.0 × 10-5 to 1.0 × 10-3 M and detection limit of 4.39 x 10-7 M was established.

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Milewski, Daniel Aaron. « Statistical analysis of New York state surface soil background concentrations for select polyaromatic hydrocarbons (PAHs) ». 2005. http://proquest.umi.com/pqdweb?did=994251641&sid=16&Fmt=2&clientId=39334&RQT=309&VName=PQD.

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Thesis (M.S.)--State University of New York at Buffalo, 2005.
Title from PDF title page (viewed on Mar. 16, 2006) Available through UMI ProQuest Digital Dissertations. Thesis adviser: Weber, Scott A., Rabideau, Alan J. Includes bibliographical references.

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謝, 永發, et Yongfa Xie. « Synthesis, Structure, and Electronic Properties of Novel Polyaromatic Hydrocarbons Annulated with Sulfur and Nitrogen Heterocycles ». Thesis, 2013. http://hdl.handle.net/2237/18987.

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Suter, Katie Ann. « How Physical and Chemical Properties Change Ice Nucleation Efficiency of Soot and Polyaromatic Hydrocarbon Particles ». Thesis, 2011. http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-9734.

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Heterogeneous freezing processes in which atmospheric aerosols act as ice nuclei (IN) cause nucleation of ice crystals in the atmosphere. Heterogeneous nucleation can occur through several freezing mechanisms, including contact and immersion freezing. The mechanism by which this freezing occurs depends on the ambient conditions and composition of the IN. Aerosol properties change through chemical aging and reactions with atmospheric oxidants such as ozone. We have conducted a series of laboratory experiments using an optical microscope apparatus equipped with a cooling stage to determine how chemical oxidation changes the ability of atmospheric aerosols to act as IN. Freezing temperatures are reported for aerosols composed of fresh and oxidized soot and polyaromatic hydrocarbons (PAHs) including anthracene, phenanthrene, and pyrene. Our results show that oxidized soot particles initiate ice freezing events at significantly warmer temperatures than fresh soot, 3 °C on average. All oxidized PAHs studied had significantly warmer freezing temperatures than fresh samples. The chemical changes presumably causing the improved ice nucleation efficiency were observed using Fourier Transform Infrared Spectroscopy with Horizontal Attenuated Total Reflectance (FTIR-HATR). The addition of C=O bonds at the surface of the soot and PAHs led to changes in freezing temperatures. Finally, we have used classical nucleation theory to derive heterogeneous nucleation rates for the IN compositions in this research. The overall efficiency of the IN can be compared in order of least efficient to most efficient: fresh phenanthrene, fresh anthracene, fresh soot, oxidized phenanthrene, fresh pyrene, oxidized anthracene, oxidized soot, and oxidized pyrene. Overall oxidation of aerosols increases their ability to act as IN. Our results suggest that oxidation processes facilitate freezing at warmer temperatures at a broader range of conditions on the atmosphere.

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