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Melidonie, Jason, Junzhi Liu, Yubin Fu, Jan J. Weigand, Reinhard Berger i Xinliang Feng. "Pyrene-Fused s-Indacene". ACS Publications, 2018. https://tud.qucosa.de/id/qucosa%3A36576.
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One antiaromatic polycyclic hydrocarbon (PH) with and without solubilizing tert-butyl substituents, namely s-indaceno[2,1-a:6,5-a′]dipyrene (IDPs), has been synthesized by a four-step protocol. The IDPs represent the longitudinal, peri-extension of the indeno[1,2-b]fluorene skeleton towards a planar 40 π-electron system. Their structures were unambiguously confirmed by X-ray crystallographic analysis. The optoelectronic properties were studied by UV/vis absorption spectroscopy and cyclic voltammetry. These studies revealed that peri-fusion renders the IDP derivatives with a narrow optical energy gap of 1.8 eV. The maximum absorption of IDPs is shifted by 160 nm compared to the parent indenofluorene. Two quasi-reversible oxidation as well as reduction steps indicate an excellent redox behavior attributed to the antiaromatic core. Formation of the radical cation and the dication was monitored by UV/vis absorption spectroscopy during titration experiments. Notably, the fusion of s-indacene with two pyrene moieties lead to IDPs with absorption maxima approaching the near infrared (NIR) regime.
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Mangnall, T. I. "Pyrene based Metal Organic Frameworks". Thesis, University of Liverpool, 2016. http://livrepository.liverpool.ac.uk/3000462/.
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Metal Organic Frameworks (MOFs) are a type of multifunctional porous material. Comprised of metal centres or metal clusters known as Secondary Building Units (SBUs) linked together into an extended 1, 2 or 3 dimensional structure by bridging organic ligands coordinated to the metal SBUs. MOFs offer the opportunity to customise the pore size and chemical functionality of the fra mework. The degree of customisation possible from the wide array of different metal clusters and organic ligands MOFs have been proposed for many applications such as gas storage, separation, catalysis, photocatalysis, sensing and drug delivery. In this thesis the synthesis and characterisation of pyrene based MOFs is presented and the hydrogen evolution photocatalytic applications are tested. This thesis contains details on three different MOFs. Firstly a new aluminium pyrene MOF which was characterised and tested for photocatalysis and CO 2 and CH 4 storage applications; which also had platinum nanoparticles successfully incorporated within the pores. Secondly a very recently reported zirconium pyrene MOF was made, had its photocatalytic applications exp lored for the first time and had platinum deposited within the pores. Thirdly a new Europium Pyrene MOF was developed using high throughput techniques and its new structure was calculated from single crystal XRD.
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Launen, Loren A. "Pyrene biodegradation by Penicillium janthinellum SFU403". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0022/NQ51887.pdf.
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TEIXEIRA, SILVIO CESAR GODINHO. "PYRENE ADSORPTION IN BRAZILIAN SOILS STUDY". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2008. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=12309@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROA maioria dos estudos envolvendo adsorção de hidrocarbonetos policíclicos aromáticos (HPA) é realizada em solos de regiões de clima frio. Como em países tropicais as características dos processos pedológicos e os solos resultantes são diferentes há necessidade desses estudos em solos brasileiros. Com esse objetivo, este trabalho estudou a adsorção de pireno em sete categorias representativas de solos brasileiros: Argissolo, Latossolo Amarelo, Latossolo Vermelho acriférrico, Latossolo Vermelho Amarelo distrófico, Neossolo Quartzarênico, Organossolo e Vertissolo. Foram realizados ensaios de adsorção usando massa de amostra dos solos de 2,5 g e 5,0 g. Para todas as categorias de solos estudados observou-se diferentes tempos de equilíbrio tanto nos estudos feitos com 2,5 g de solo quanto naqueles com 5,0 g. Nos experimentos realizados com a menor massa (2,5 g), observou-se que os perfis das curvas de adsorção para o Latossolo Vermelho acriférrico e para o Vertissolo apresentaram diferenças significativas sugerindo maiores competições pelos sítios de sorção. Para as demais categorias não foi observada diferença significativa no perfil das curvas de adsorção. Verificou-se ainda que não foi somente o teor de matéria orgânica responsável pelo equilíbrio do processo de adsorção como esperado. A presença de argilas expansivas pode ter contribuição para o aumento da quantidade de pireno adsorvida no solo (Q), como foi verificado para o Vertissolo. Foi observado que as categorias de solos estudadas apresentam características físico-químicas e Koc muito diferentes indicando que o processo de adsorção de pireno nestes solos não pode ser considerado como um modelo único. Neste trabalho o processo de adsorção de pireno foi descrito pelas isotermas de Langmuir (Argissolo e Latossolo Vermelho acriférrico), de Langmuir com linearização (Latossolo Vermelho Amarelo distrófico), de BET (Neossolo Quartzarênico) e isoterma linear (Vertissolo). Os resultados obtidos para o Latossolo Amarelo não se ajustam aos modelos de isotermas testados.
Since most of the studies that involve polycyclic aromatic hydrocarbons (PAH) adsorption in soils are make in regions of temperate or cold climate. In tropical countries, the characteristics of the pedological processes and the resultant soils are quite different there is the necessity of working on new studies in the Brazilian soils. In this dissertation, the pyrene adsorption in seven differents Brazilian soils was studied: Clays soils, Yellow Latosoil, Red Anionic Latosoil, Red Yellow Latosoil, Neosoil Quartzarenic, Organic soil and Vertisoil. Two groups of adsorption tests were carried out, in the first one we used samples of 2.5g of soil and in the second one the soil mass was increased to 5.0g. To all soils, it was possible to observe that, when the initial mass of soil was changed, different times of reaction were needed so that the sorption process could reach the thermodynamic equilibrium. And yet because of this bigger competition, the profile of the Red Anionic Latosoil and Vertisoil curves, obtained by the usage of different pyrene/soil relations, presented meaningful differences when compared. The presence of the swelling clays may contribute to the increase of the quantity of pyrene adsorpted in the soil (Q), such as happened in the Vertisoil. In this work, was found the Langmuir`s isotherms to Clays soils and Red Yellow Latosoil, BET to Neosoil Quartzarenic and linear isotherm to Vertisoil.
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Karabaeva, Kanykey E. "Photochemistry of Masked Pyrene-4,5-Dione". Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1371083757.
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Castle, Saffron Jane. "Sensing bilayer pressures with pyrene-labelled probes". Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281742.
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Carter, Tom Scott. "Synthetic lectins with pyrene at the core". Thesis, University of Bristol, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.702443.
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Carbohydrates are displayed on the outer layer of cells by glycoproteins and glycolipids, forming the glycocalyx. These carbohydrates hold a huge amount of information, acting as a cell 'barcode', facilitating communication and acting as targets for pathogens. The proteins which recognise carbohydrates in nature are called lectins. Synthetic mimics of these proteins, binding through noncovalent interactions in water, are termed 'synthetic lectins'. The design and synthesis of these synthetic lectins could allow reading of parts of the cell barcode and give a greater understanding of the operation of natural lectins. Furthermore, robust selective synthetic lectins could act as sensors for important sugars such as N-acetylglucosamine (important in protein regulation) or blood glucose levels (for surgery or diabetics). However the design of synthetic lectins that are able to overcome the hydromimetic nature of carbohydrates and show selectivity between carbohydrates is very difficult. Within this body of work a variety of synthetic lectin architectures are presented, with their design, synthesis and binding properties reported. Two designs within are of particular note. Firstly, a highly cationic pyrene based platform shaped receptor (PyPlat-Guan) was prepared to target α-sialosides (components of important antigens such as Sialyl Lewis X). This resulted in strong selective binding of methyla α-sialoside and both the first non-macrocyclic synthetic lectin and the first synthetic lectin with divalency by design. Secondly, a pyrene based four-pillared cage receptor was prepared (Py4P) to target O-linked N-acetylglucosamine (O-GlcNAc). This resulted in a pair of receptor isomers, which demonstrate the highest binding affinities ever obtained by a synthetic lectin for a monosaccharide. It was then also possible to test the interaction of these synthetic lectins with a glycopeptide, which was bound with unprecedented affinity.
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Fagla-Amoussou, Akouavi Balbine. "Etude des interactions polluants aromatiques polycycliques (HAP)-récepteurs adrénergiques-phospholipides membranaires dans le tissu adipeux". Thesis, Vandoeuvre-les-Nancy, INPL, 2010. http://www.theses.fr/2010INPL080N/document.
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L'obésité est une maladie définie par une accumulation de masse grasse dans le tissu adipeux ayant des conséquences néfastes pour la santé. Les causes de l’obésité sont multiples. Dans un travail récent, il y a été démontré le rôle de la pollution environnementale dans la prise de poids. Dans ce travail, les hypothèses selon lesquelles les récepteurs adrénergiques situés à la surface des cellules adipeuses seraient le siège de l’action des polluants aromatiques polycycliques ont été vérifiées par le dosage de plusieurs agonistes et antagonistes spécifiques et non spécifiques en présence ou non du benzo[a]pyrène sur des récepteurs humains et de cellules d’hamster chinois (CHO). Les quantités d’AMPc obtenues montrent que les HAP ne se déposent pas sur les récepteurs β1, β2, β3 adrénergiques.Cette accumulation se fait au niveau des phospholipides de la membrane cytoplasmique des cellules. Ce qui cause une rigidité des membranes.Cette observation tend à renforcer l'hypothèse selon laquelle le benzo[a]pyrène induirait une inhibition de la lipolyse par l'accumulation au niveau de la bicouche de phospholipides et des changements de conformation de la bicouche de phospholipides dans les environs des récepteurs à sept domaines transmembranaires qui sont β-adrénergiques.La liaison de la bicouche phospholipidique avec les HAP utilisés est une réaction exothermi-que avec un faible dégagement de chaleurObesity is a disease defined by an accumulation of fat in adipose tissue with adverse consequences for health. The causes of obesity are many.In recent work, there was demonstrated the role of environmental pollution in weight gain.In this work, the assumptions that the adrenergic receptors on the surface of fat cells would home to the accumulation of polycyclic aromatic pollutants have been verified by measurement of several agonists and antagonists specific and non-specific in the presence or absence of benzo[a]pyrene receptors on human cells and Chinese hamster (CHO). The amounts of cAMP obtained showed that PAHs are not deposited on β-receptors, β1, β2, β3 adrenergic receptors.This accumulation occurs at the cytoplasmic membrane phospholipids of the cells. What cau-ses stiffness of the membranes. This observation tends to reinforce the hypothesis that benzo [a]pyrene induce an inhibition of lipolysis by the accumulation in the phospholipid bilayer and conformational changes of the bilayer phospholipids in the vicinity of receptors seven transmembrane domains which are β-adrenergic receptors
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Boateng, Stephen. "Photophysical properties of pyrene, 2,7 diazapyrene and 1,3-bis(β-naphthyl)propane". Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc3999/.
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The luminescence properties of Van Der Waals' dimers and clusters of pyrene and diazapyrene have been investigated. Excimers, dimeric species which are associative in an excited electronic state and dissociative in their ground state, have long been established and play an important role in many areas of photochemistry. My work here focuses on the luminescence and absorption properties of ground state dimers/aggregates, which are less understood, and allows further characterization of the ground state and excited state association of these aromatic molecules.
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Chercka, Dennis [Verfasser]. "Pyrene derivatives as donors and acceptors / Dennis Chercka". Mainz : Universitätsbibliothek Mainz, 2015. http://d-nb.info/1069521256/34.
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Bilash, О. М., О. М. Galaichenko, O. A. Sushko i M. M. Rozhitskii. "New nanophotonic detection method of benzo[a]pyrene". Thesis, КНУ імені Тараса Шевченка, 2011. http://openarchive.nure.ua/handle/document/8853.
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Benzo[a]pyrene is the representative of polycyclic aromatic hydrocarbons family, the substance of the first hazard class. In present work for the development of novel nanophotonic assay method as a PAH representative benzo[a]pyrene was choose.
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De, Halleux Véronique. "Fluorescent discotic liquid crystalline materials based on pyrene". Doctoral thesis, Universite Libre de Bruxelles, 2002. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211395.
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Maivaldová, Iva. "Interakce fosfolipidů s polyelektrolyty ve vodném prostředí". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-216675.
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This diploma thesis is focused on determination of aggregation behavior of selected phospholipids (lecithin; 1,2-dipalmitoyl-sn-glycerol-3-phosphocholine) in water and on the effect of native hyaluronan addition of various molecular weights and concentrations on this behavior. The behavior has been investigated with fluorescence spectroscopy using pyrene and perylene as fluorescence probes being able to penetrate into hydrophobic cavities of formed aggregates. Critical aggregation concentration and the concentration at which lecithin begins to aggregate have been determined. Regarding 1,2-dipalmitoyl-sn-glycerol-3-phosphocholine, it was possible to determine only the beginning of aggregation value. The values of this parameter for lecithin and for 1,2-dipalmitoyl-sn-glycerol-3-phosphocholine correspond in the order. It has been investigated, that the addition of native hyaluronan has only in some systems slight effect on the aggregate behavior of selected phospholipids.
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Barboříková, Hana. "Směsné lipidy a jejich interakce s biopolymery". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-316157.
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This thesis focuses on the study of interactions between hyaluronan and lipid DOTAP and its mixtures with DPPC in water. First, the aggregation behavior of the lipid itself and its mixtures was measured, afterwards the influence of hyaluronan in different concentration was studied. Further the fluorescence anisotropy of fluorescence probe DPH in these mixtures and influence of cholesterol was measured. These properties were investigated by fluorescence spectoscopy using pyrene and DPH as fluorescence probes. The measurements revealed that the addition of hyaluronan has observable influence on the aggregation behavior of the lipid DOTAP and its mixtures with DPPC and that cholesterol influences liposomes fluidity.
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Sho, Michiei 1976. "Characterization of pyrene degradation by Mycobacterium sp. strain S65". Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79125.
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The microbial degradation of pyrene, a 4-ring polycyclic aromatic hydrocarbon (PAH), has been elucidated with the increasing number of pyrene-degrading bacteria that have been isolated in recent years. A pyrene degrading bacterium identified as Mycobacterium sp. strain S65, was isolated from a jet-fuel contaminated site in Sept-Iles, northern Quebec, Canada. S65 utilized pyrene, phenanthrene, and fluoranthene as sole carbon and energy sources, but did not degrade naphthalene, anthracene, and fluorene. Pyrene mineralization was enhanced by adding benz[a]anthracene, benzy[a]pyrene, or phenanthrene as cosubstrates. When added to PAH contaminated soil as a potential bioaugmentation agent, S65 did not appear to survive well, nor was it effective at degrading PAHs under these conditions.Pyrene catabolic genes in S65 were partially characterized by Southern hybridization using a probe constructed from the naphthalene inducible pyrene dioxygenase gene, nidA, from the pyrene-degrading bacterium, Mycobacterium sp. strain PYR-1.
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Ross, Helen L. "The metabolism of benzo(a)pyrene in human cells". Thesis, University of Nottingham, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253019.
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Alqurashy, Bakhet. "Pyrene based donor-acceptor conjugated polymers for photovoltaic applications". Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/17244/.
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Photovoltaic devices have emerged as a promising and efficient technology to address rising global energy demands as the current energy source, which depends on fossil fuels is running out. This technology has the ability to directly convert sunlight to electricity. Inorganic photovoltaic devices exhibit relatively high power conversion efficiencies from 8 to 29%. However, the high cost of these devices has impeded their widespread usage. Intensive research has been done in order to find different approaches to explore less expensive materials to maintain a technology path for photovoltaic devices. Organic photovoltaic devices based on conjugated polymers have gained a large amount of attention from researchers and academicians owing to their potential characteristics when compared with inorganic solar cells. The potential characteristics of organic photovoltaic devices are as follows: they are economical, light weight, and their roll to-roll production is fast and inexpensive. Several types of π-conjugated polymers have been synthesized and applied as electron donor materials in organic photovoltaic devices, either as homopolymers or alternating donor-acceptor copolymers. In this project, different type of donor-acceptor conjugated polymers, consisting of pyrene as the electron donor and benzothiadiazole or thieno[3,4-c]pyrrole-4,6-dione as the electron acceptor, have been prepared via palladium catalysed cross-coupling reactions such as Stille or direct arylation. The purity and identity of all monomers were confirmed by 1H and 13C NMR spectroscopy, GC-MS and elemental analysis. The structures of all synthesised polymers have been confirmed by 1H NMR spectroscopy and elemental analysis. The thermal, optical and electrochemical properties of all polymers have been investigated using TGA, UV-vis, CV and XRD in order to evaluate their suitability for application in organic photovoltaic devices. The optical band gap of all polymers ranged between 1.76 and 2.06 eV. Bulk heterojunction devices were fabricated from all polymers using PC70BM as the electron acceptor. Preliminary studies indicated that the power conversion efficiencies of the polymers ranged from 0.33 and 2.06 %.
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Weyand, Eric Henry. "The metabolic fate of benzo [a] pyrene in vivo". Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/77786.
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[³H]-B[a]P absorption, distribution, metabolism, excretion and macromolecular binding in male Sprague-Dawley rats were investigated following administration by intratracheal instillation through a cannula. [³H]- radioactivity in various organs was determined at timed intervals between 5 and 360 min. Elimination of radioactivity from lungs was biphasic with half-lives of 5 and 116 min. Radioactivity in liver increased rapidly, reaching a maximum of 21% of the dose within 10 min after installation and decreasing thereafter, until less than 5% of the dose was detected at 360 min. Radioactivity in intestinal contents accounted for 45% of the dose 360 min after installation. Carcass accounted for 15-30% of the dose within the time intervals investigated. Toxicokinetic parameters to describe B[a]P disposition following intratracheal administration were similar to those following intravenous injection of B[a]P. HPLC was used to identify various types of metabolites in lungs, liver, and intestinal contents at selected times after B[a]P instillation. Notably, quinones were at highest concentrations in both lung and liver 5 min after installation, accounting for 12 and 7% of organic extractable material, respectively. Covalent binding of B[a]P metabolites to DNA, RNA, and protein at 6 hrs after installation was also quantified for lung and liver. There was extensive binding of metabolites to RNA while much lesser amounts of metabolites were associated with protein and DNA in both organs. Six B[a]P:DNA adducts were detected in lung, while only three such adducts were detected in liver.
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Biliary excretion of B[a]P was investigated in SpragueDawley rats, Gunn rats, hamsters, and guinea pigs following instillation of [³H]-B[a]P. [³H]-B[a]P was administered at concentrations ranging from 6 ng to 380 μg and biliary radioactivity was monitored for 6 hrs. In addition, tissue distribution of radioactivity was determined. Species differences in biliary excretion of B[a]P and/or metabolites were detected. Rats and guinea pigs, but not hamsters, exhibited differences in biliary excretion of low and high doses of B[a]P. Phase II metabolites of B[a]P in bile were quantified for all species. The majority of these metabolites were glucuronides and thio-ether conjugates. Enterohepatic circulation of B[a]P biliary metabolites was investigated in Sprague-Dawley rats.Ph. D.
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Zvaigzne, Anita Ilze. "Thermochemical investigations of crystalline solutes in non-electrolyte solutions: Mathematical representation of solubility data and the development of predictive solubility equations in systems with specific and non-specific interactions". Thesis, University of North Texas, 2008. https://digital.library.unt.edu/ark:/67531/metadc28369/.
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Understanding the thermodynamic properties of multicomponent mixtures is of critical importance in many chemical and industrial applications. Experimental measurements become progressively difficult as the number of solution components increases -- producing the need for predictive models. Problems in development of predictive models arise if the mixture has one or more components that interact through molecular complexation or association. Experimental solubilities of anthracene and pyrene dissolved in binary systems containing one or more alcohols were measured in order to address this problem. Alcohols examined in this study were: 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 3-methyl-1-butanol, and 1-octanol. In binary solvent mixtures containing only a single self-associating alcoholic solvent, the alkane cosolvents studied were: n-hexane, n-heptane, n-octane, 2,2,4-trimethylpentane, cyclohexane, methylcyclohexane, tert-butylcyclohexane. Predictive solubility equations were developed using mobile order theory. This approach differs from classical solution models by representing hydrogen bonding with a probability term rather than with expressions derived from stepwise equilibria or expressions to represent hypothetical solution aggregates. Results were compared with the predicted solubilities found from using expressions developed using the Kretschmer-Wiebe and Mecke-Kempter approaches for modeling associated solutions. It was found that the mobile order approach provided reasonably accurate predictions for the solute solubilities in the systems studied. The limitations and applications for mathematical methods of representing experimental isothermal solubility data were also studied for 72 systems. Two possible descriptive forms for this mathematical representation were suggested based on the various nearly ideal binary solvent (NIBS) and modified Wilson models.
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Ramos, Chagas Gabriela. "Polymères électrodéposés nanostructurés : design et propriétés de films dérivés de monomères du thienothiophène et du pyrène". Thesis, Université Côte d'Azur (ComUE), 2017. http://www.theses.fr/2017AZUR4108/document.
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Le contrôle de l'hydrophobie de surface et de l'adhésion à l'eau est un outil fondamental pour diverses applications. L'électropolymérisation est une méthode très polyvalente qui peut être utilisée pour contrôler ces paramètres et pour la production de matériaux nanostructurés à façon. Ici, nous montrons qu'en différentiant le noyau polymérisable (thienothiophène ou pyrène), des morphologies et des mouillabilités de surface variées sont produites par un procédé direct d'électropolymérisation. Des nanotubes et des structures en forme d'arbre sont obtenus en utilisant des dérivés de thienothiophène sans utiliser de membrane structurante. En fonction de la méthode d'électrodéposition et des paramètres, différents types de nanotubes sont obtenus. La méthode électrochimique et le substituant greffé jouent un rôle important dans la structuration de surface. Les surfaces affichent différents angles de contact, mais toujours une forte adhésion à l'eau. D'autre part, des pyrènes avec divers substituants sont utilisés pour conduire à des propriétés hydrophobes/superhydrophobes, fluorescentes et, pour la première fois, à des applications en anti-bioadhesion et anti-biofilm. Des copolymères de pyrène ont été électrodéposés pour donner des surfaces avec une sensibilité au pH et une adhérence contrôlable à l'eau. Une nouvelle méthode utilisant un système de catapult a été mise en œuvre pour mesurer le comportement adhésif de surfaces collantes et non collantes. Ainsi, il a été montré le rôle important du noyau de monomère sur les propriétés finales des surfaces ouvrant de nouvelles portes pour explorer ce domaine dans le domaine des sciences de surface et de leurs applicationsControlling surface hydrophobicity and water adhesion is a fundamental tool for various applications. Electropolymerization is a very versatile method that can be used to control these parameters and for the production of tunable nanostructured materials. Here, we show that by differentiating the polymerizable core (thienothiophene or pyrene), varied surface morphologies and wettabilities are produced by a direct electropolymerization process. Nanotubes and tree-like structures are obtained starting from thienothiophene derivatives without using any template. Depending on the electrodeposition method and parameters, different kinds of nanotubes are obtained. The electrochemical method and the grafted substituent play an important role on the surface structuration. The surfaces display different contact angles, but always with high water adhesion. On the other hand, pyrenes with various substituents are employed to produce hydrophobic/ superhydrophobic and fluorescent surfaces and, for the first time, with anti-bioadhesion and anti-biofilm properties. Copolymers of pyrenes were electrodeposited to yield surfaces with pH-responsivity and controllable water adhesion. A new method using a catapult system was implemented to measure the adhesive behavior of sticky and non-sticky surfaces. Thus, it has been shown the important role of the monomer core on the final properties of the surfaces opening new doors to explore this domain in the surface science field and applications
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Shirdel, Javid. "Photo-physical characterization of flavin-pyrene-phenothiazine molecular photonic complexes". [S.l.] : [s.n.], 2007. http://deposit.ddb.de/cgi-bin/dokserv?idn=985128062.
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RIZEL, PATRICIA. "QUALITATIVE STUDIES FOR DETERMINATION OF PYRENE METABOLITES USING GC/MS". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2003. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4329@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOOs Hidrocarbonetos Policíclicos Aromáticos (HPAs) são contaminantes carcinogênicos e mutagênicos, freqüentemente encontrados no ambiente. Muitos organismos são capazes de metabolizá-los rapidamente, tornando de fundamental importância o desenvolvimento de técnicas analíticas para a determinação de seus metabólitos. A determinação do 1- hidroxipireno é considerada com uma das primeiras etapas para a avaliação do risco ambiental por exposição dos HPAs. O pireno é um dos compostos predominantes desta classe de xenobióticos e o 1-hidroxipireno é o seu principal metabólito. Neste estudo é apresentado uma método para análise qualitativa do 1-hidroxipireno. Testes foram realizados afim de viabilizar a aplicação de uma metodologia para análises de rotina em amostras biológicas. O método escolhido envolve uma etapa de hidrólise ácida com subsequente extração líquido-líquido para obtenção do 1- hidroxipireno. A cromatografia de permeação em gel (CPG) foi empregada como um método de separação de lipídios, seguida de uma etapa de cromatografia líquida de coluna aberta. Uma vez que o 1-hidroxipireno é um composto de baixa volatilidade, foi incluída uma etapa de derivação com BSTFA e seguida de análise por CG/EM.
Polycyclic Aromatic Hydrocarbons are ubiquitous pollutants that usually present carinogenic and mutagenic effects. Several organisms are able to metabolize them quickly, and therefore becoming very important the development of analytical techniques for their metabolites determination. The chemical analyses of 1-hydroxipyrene is one of the first steps for evaluation of environmental assessment by PAH exposure. Pyrene is one of the principal compounds of this xenobiotic class and 1-hydroxipyrene is yours major metabolite. This study presents a method for qualitative analysis of 1-hydroxipirene. Tests were performed due to allow the use of a methodology for routine analysis in biological samples. The chosen method included acid hydrolysis followed of liquid-liquid extraction to obtain 1- hydroxipyrene. Gel permeation chromatography (GPC) was applied as a lipid separation method, and then liquid chromatography of opened column. As long as the 1- hydroxipyrene is a low volatile compound, it was included one step of derivatization with BSTFA followed by gas chromatography/mass spectrometer (GC/MS) analysis.
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Yang, Yang. "The in vivo metabolism of benzo[a]pyrene studied by chromatography in combination with mass spectrometry /". Stockholm, 1997. http://diss.kib.ki.se/1997/91-628-2640-9/.
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Souleymanou, Myriam. "Pyrene-tagged Ligands as a Bridge between Homogeneous and Heterogeneous Catalysis". Doctoral thesis, Universitat Rovira i Virgili, 2019. http://hdl.handle.net/10803/668974.
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La present tesi tracta sobre el desenvolupament de catalitzadors homogenis que contenen fragments poliaromàtics
per facilitar el seu ancoratge en suports sòlids per aconseguir la fàcil separació i reciclatge del catalitzador. Es van
triar els grups pirè, ja que és conegut que promouen interaccions aromàtiques fortes pi-pi per apilament en
superfícies de carboni. En conseqüència, el treball s'ha centrat en els suports de carboni (nanotubs de carboni, òxid
de grafè reduït i perles de carboni) com a suports sòlids per a aquesta estratègia d'ancoratge no covalent en suports
sòlids. A més, s'ha explorat un sistema catalític bifàsic com una altra estratègia per al reciclatge i la reutilització de
catalitzadors homogenis. Aquest sistema catalític bifàsic, que consisteix en líquids iònics (IL) i diòxid de carboni
supercrític (scCO2), s'usa en la reacció de telomerització de 1,3-butadiè amb diòxid de carboni per produir ä-lactona
en un flux continu.La presente tesis trata sobre el desarrollo de catalizadores homogéneos que contienen fragmentos poliaromáticos que se han introducido con el objetivo de facilitar el anclaje en soportes sólidos para conseguir la fácil separación y el reciclaje del catalizador. Se eligieron grupos pireno, ya que es conocido que promueve interacciones aromáticas fuertes pi-pi por apilamiento en superficies de carbono. En consecuencia, el trabajo se ha centrado en los soportes de carbono (nanotubos de carbono, óxido de grafeno reducido y perlas de carbono) como materiales para esta estrategia de anclaje no covalente en soportes sólidos. Además, se ha explorado un sistema catalítico bifásico como otra estrategia para el reciclaje y la reutilización de catalizadores homogéneos. Este sistema catalítico bifásico, que consiste en líquidos iónicos (IL) y dióxido de carbono supercrítico (scCO2), se usa en la reacción de telomerización de 1,3-bytadieno con dióxido de carbono para producir ä-lactona en un flujo continuo.
The present thesis deals with the development of established homogeneous catalysts bearing polyaromatic fragments that would facilitate catalyst separation and recycling. Pyrene tags were chosen as it is a well-known antenna that promotes strong aromatic pi-pi stacking interactions onto carbon surfaces. Consequently, we focused our attention on carbon supports (carbon nanotubes, reduced graphene oxide and carbon beads) as solid supports for this noncovalent anchoring strategy on solid supports. In addition, a biphasic catalytic system as another strategy for the recycling and reuse of homogeneous catalysts is explored. This biphasic catalytic system consisting of ionic liquids (ILs) and supercritical carbon dioxide (scCO2) was used in the Pd-catalyzed telomerization reaction of 1,3-butadiene with carbon dioxide to yield ä-lactone in a continuous flow-manner.
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Stylianou, Kyriakos C. "Biologically derived and pyrene-based metal-organic frameworks for advanced applications". Thesis, University of Liverpool, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.569888.
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Metal-Organic Frameworks (MOFs) represent a new type of multi functional porous materials. These materials can be obtained from the connection of metal centres or clusters and organic ligands in such way that extended ID, 2D or 3D structures can be isolated. The unlimited possibilities of connecting the different building blocks within these materials make possible the formation of networks with a range of pore sizes and applications in gas storage and separation, catalysis, molecular sensing and drug delivery. In this thesis, the synthesis and characterisation of adenine based and pyrene derived MOFs is presented. Based on the physical properties of these MOFs, we are demonstrating that they can potentially used for advanced applications in CO2 capture, C}--4 storage, C02/C}--4 separation, xylene separation, sensing and base pairing recognition. The first part of this thesis deals with the synthesis of novel adenine based MO F s. Within the isolated MOFs, adenine provides a wide range of binding modes for metal coordination and different protonated forms acting as a bridging or terminal ligand. The diverse functionality of small biologically relevant building blocks such as adenine can tune the chemistry of MOF type structures to permit increased chemical interactions with guest molecules (C02 and C}--4) for applications such as gas storage and separation. The second part describes the design of a tetracarboxylate ligand based on an optically active pyrene core, H4 TBAPy. The choice of the ligand for the construction of extended networks is important for the construction of fluorescent MOFs for sensing applications. The isolated MOFs show interesting properties for CO2 capture and CH4 storage and due to the specific size and shape of the channels and nature of the polyaromatic ligand used for the isolation of the frameworks, aromatic molecules were introduced for separation applications. The [mal part demonstrates the synthesis of a network based on Zn, adenine and }--4TBAPy. The Watson-Crick face of the nucleobase within this framework is located within the channels, responsible for the hydrogen bonding with thymine, the pair base of adenine. Thymine solution isotherms revealed that the 3D structure can adsorb thymine molecules and this is further confirmed with Infrared Spectroscopy and Thermogravimetric and Elemental Analyses. In conclusion, this thesis represents a small contribution to the extraordinary field of Metal-Organic Framework chemistry. The formation of novel materials with unprecedented network topologies and possible applications in gas storage, gas and liquid separation and molecular sensing is important in order to create novel materials with improved and advanced properties.
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Wang, Yixi, i 王义熙. "Exposure to benzo[a]pyrene and breast cancer : a systematic review". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206972.
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Objective: Breast cancer is the most common invasive cancer in women in the world. Benzo[a]pyrene (B[a]P), a carcinogenic component of cigarette smoke and grilled meat, was related to expression of enzymes involved in several epithelial malignancies including breast cancer. Understanding the association of exposure to B[a]P and breast cancer risks may inform potential disease preventive measures. The objective of this systematic review was to assess from epidemiological studies the relationship between the exposure to and the risks and development of breast cancer in humans.
Study design: A systematic search using keywords in PubMed (1990-2014), CNKI (1994-2014) and Google Scholar databases was carried out to identify eligible epidemiological studies on the association between the exposure to B[alP and breast cancer risks published during 1990-2014.
Results: Nine studies met the inclusion criteria and included in this review. All nine included studies used case-control design, with B[a]P exposure mainly proxied by benzo(a)pyrene diolepoxide (BPDE) and dietary consumption of B[a]P-rich food. Of these, seven found a significant positive association between B[a]P exposure and breast cancer risks, after adjustment for age, family history of breast cancer, smoking, ethnicity, alcohol use and parity in most studies.
Discussion: Discuss the potential reason for inconsistence, the possible biological pathways explaining the role of B[a]P in the development of breast cancer, limitations of the studies and the public health implication from this review.
Conclusion: A positive association between B[a]P exposure and breast cancer risks was suggestive from the systematic review. However given the limited number of studies included, further prospective cohort studies in humans as well as molecular/animal studies are warranted to explore the impact of B[a]P on the development of breast cancer to inform evidence based preventive measures against breast cancer.published_or_final_version
Public Health
Master
Master of Public Health
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Lawrence, Deirdre Michelle. "DNA adducts as molecular biomarkers of exposure to benzo(a)pyrene". Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42792.
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Gu, Jie. "Effects of benzo[a]pyrene on the biological function of eosinophils". HKBU Institutional Repository, 2011. http://repository.hkbu.edu.hk/etd_ra/1279.
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Boateng, Stephen Omary Mohammad A. "Photophysical properties of pyrene, 2, 7 diazapyrene and 1, 3-bis ([beta] naphthyl) propane". [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3999.
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Hurk, Peter van den. "Interactive effects of cadmium and benzo(a)pyrene in mummichog (Fundulus heteroclitus)". W&M ScholarWorks, 1998. https://scholarworks.wm.edu/etd/1539616705.
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van, den Hurk Peter. "Interactive effects of cadmium and benzo(a)pyrene in mummichog (Fundulus heteroclitus)". W&M ScholarWorks, 1998. https://scholarworks.wm.edu/etd/1539616888.
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When animals are exposed to mixtures of environmental pollutants, it is generally assumed that the toxic effects of the individual components are additive. However, examples of synergistic and antagonistic effects have been described. to study the mechanisms of interaction between a metal and a polycyclic aromatic hydrocarbon, mummichog (Fundulus heteroclitus) were injected with combinations of cadmium (Cd) and benzo (a) pyrene (BP). Measured effect parameters were: mortality, BP-metabolite production in isolated hepatocytes and microsomes, hepatic induction of CYP1A (the BP metabolizing enzyme) and metallothionein (the Cd binding protein), and biliary excretion of BP-metabolites. The mortality data demonstrated that both synergistic and antagonistic effects can occur. A Cd dose of 0.32 mg/kg significantly reduced the expected mortality caused by BP. In contrast, a BP dose of 10 mg/kg significantly increased the toxicity of Cd above the expected mortality. to study the mechanisms of these interactive effects, liver cells (hepatocytes) were isolated from fish that were previously injected with combinations of Cd and BP. These cells were exposed to radiolabeled BP to study the rate of BP metabolism, and the formation of BP-metabolites. Cadmium exposure had an overall inhibiting effect on the metabolism of BP. No effects of Cd were observed on the formation of individual metabolites. to distinguish between direct interference of Cd with CYP1A at the active site versus indirect interference by inhibiting CYP1A induction, microsomal preparations were evaluated for enzyme activity and enzyme concentration. While there was no direct effect of Cd on enzyme catalytic activity, there was an effect on CYP1A production. The demonstrated inhibition of BP metabolism by Cd would suggest a reduced excretion of BP-metabolites. However, analysis of bile and water samples after fish were injected with radiolabeled BP demonstrated an enhanced biliary excretion of conjugated BP-metabolites under influence of Cd. Cadmium exposure caused a significant induction of hepatic metallothionein in the fish. When BP was dosed together with Cd, the induction of MT was inhibited. The hypothesis that reactive BP metabolites would compete with Cd for binding sites on MT could not be confirmed. There was no measurable binding of BP to MT.
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Holínková, Petra. "Pokročilé fluorescenční techniky ve výzkumu micelárních systémů a jejich interakcí s biopolymery". Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-402106.
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The dissertation thesis deals with study of advanced steady-state and time-resolved fluorescence techniques, which can be used for study of micellar systems properties. Selected fluorescence techniques were used for characterization of Septonex and CTAB cationic micellar systems and theirs interactions with hyaluronan. Fluorescent probe pyrene was used for determination of critical micelle concentration (CMC) and micellar aggregation number of these surfactants. The changes of fluorescence behaviour of fluorescein and prodan were studied in wide concentration range of Septonex. Next chapter of thesis deals with study of Förster resonance energy transfer between perylene and fluorescein in Septonex and CTAB micellar solutions and the effect of hyaluronan addition to these systems. Also steady-state and time-resolved fluorescence anisotropy studies were used for research of the effect of hyaluronan addition to micellar solutions. The last chapter of this thesis is focused on photophysical behaviour of Prodan in different solutions (water, Septonex solutions below CMC, hyaluronan solution, Septonex micellar solution and Septonex micellar solution with hyaluronan), which was discussed on the basis of time-resolved emission spectra.
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Venerová, Tereza. "Interakce a agregace v systémech hyaluronan-aminokyseliny-tenzid". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2009. http://www.nusl.cz/ntk/nusl-216525.
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The effect of native hyaluronan addition on CMC of excluded surfactants (Tween 20, BETADET THC 2, SDS, CTAT a CTAB) in physiological solution (0,15 M NaCl) has been investigated by fluoresence spectroscopy with Pyrene and Nile red as probes. The greatest influence on CMC has been observed in systems with cationic surfactant. System of cetyltrimethylamonnium bromid has been closely studied. Solubilization experiments with a hydrophobic dye Sudan red has been realized and aggregation number of this system has been determinated via fluorescence quenching with cetylpyridinium chloride as quencher and Pyrene as fluorescence probe. Addition of hyaluronan (native or hydrophobicaly modified) reduces aggregation number of system.
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Nordling, Mirjam. "Characterization of toxicological effects of a novel in vivo benzo[a]pyrene metabolite in colonic cells /". Stockholm, 2004. http://diss.kib.ki.se/2004/91-7140-034-6/.
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Le, Thi Nhi Cong, Thi Ngoc Mai Cung, Thi Thanh Vu, Ngoc Minh Nghiem, Phuong Ha Hoang, Thi Lien Do i Thi To Uyen Do. "Pyrene degradation of biofilm-forming Paracoccus sp. DG25 isolated from oil polluted samples collected in petroleum storage Duc Giang, Hanoi". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-190617.
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In this study, a well biofilm-forming bacterial strain was isolated from oil contaminated water and sediment samples collected in petroleum storage Duc Giang, Hanoi. It was identified as Paracoccus sp. DG25 and registered in the GenBank database with the accession numbers KJ608354. Several biophysical and bio-chemical conditions for the biofilm formation of the strain were estimated such as pH, temperature, carbon sources and nitrogen sources. As the results the biofilm forming capacity was highest at pH 7, 37 oC, on maltose and supplemented with KNO3. Using these optimal conditions, the formed biofilm degraded 76.07 % of pyrene after 7 day-incubation, with the initial concentration of 300 ppm by high-performance liquid chromatography (HPLC) analysis. To our knowledge, there is rare publication on pyrene degradation by biofilm-forming bacteria. Therefore, the obtained results show that biofilm formed the strain Paracoccus sp. DG25 may considerably increase the degrading efficiency of pyrene and may lead to a new approach to treat polycyclic aromatic hydrocarbons containing in petroleum oil contaminated water in VietnamTrong nghiên cứu này, từ các mẫu đất và nước nhiễm dầu lấy tại kho xăng Đức Giang, Hà Nội, chúng tôi đã phân lập được chủng vi khuẩn có khả năng tạo màng sinh học tốt. Chủng vi khuẩn này đã được phân loại và định tên là Paracoccus sp. DG25 với số đăng ký trên ngân hàng Gen là KJ608354. Chúng tôi cũng đã nghiên cứu một số điều kiện hóa lý ảnh hưởng tới khả năng hình thành màng sinh học như pH, nhiệt độ, nguồn Carbon và nguồn Nitơ. Kết quả cho thấy, chủng DG25 có khả năng tạo màng tốt nhất ở các điều kiện pH 7, 37 oC, nguồn Carbon là maltose và nguồn Nitơ là KNO3. Sử dụng các điều kiện tối ưu này để tạo màng và đánh giá khả năng phân hủy pyrene của màng tạo thành. Bằng phương pháp sắc ký lỏng cao áp, chúng tôi đã đánh giá được hàm lượng pyrene bị phân hủy sau 7 ngày nuôi tĩnh bởi màng sinh học của chủng DG25 lên tới 76,07 % với nồng độ ban đầu là 300 ppm. Cho tới nay, chưa có nhiều công bố về hiệu quả phân hủy pyrene của các chủng vi khuẩn tạo màng sinh học. Do vậy, kết quả đạt được này mở ra khả năng sử dụng màng tạo thành bởi chủng DG25 để nâng cao hiệu quả phân hủy pyren và có thể mở ra phương pháp mới nhằm xử lý các hợp chất hydrocarbon thơm có trong nước ô nhiễm dầu ở Việt Nam
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Ayoub, Pierre. "Molecular dynamics study of pyrene excimer formation and oxidation in lipid bilayer models". Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAE038/document.
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Nous proposons une nouvelle approche pour déterminer le coefficient de diffusion dans des membranes lipidiques se basant sur la formation d'excimères. Alors que les autres modèles statistiques considèrent le système comme un ensemble de points sur un réseau, nous utilisons un modèle à gros grain afin d'étudier des bicouches lipidiques simulées à l'aide du champs de force Martini. Nous déterminons le taux de réaction dépendant du temps à partir des probabilités de survie obtenues a posteriori à l'aide des trajectoires numeriques des bicouches symétriques de DOPC (1,2-Dioleoyl-sn-glycero-3-phosphocholine) et POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) simulées à 283 K et 293 K respectivement. Les dynamiques de collision sont obtenues en distinguant virtuellement les molécules simulées. Les sondes fluorescentes sont supposées semblables aux lipides, et par conséquent, ne modifient pas la dynamique. Nous obtenons une expression générale pour la probabilité de survie en combinant approximation des paires indépendantes et propriétés d'échelle, mais aucune hypothèse n'est faite pour le taux de formation d'excimère. En superposant les intensités d'émission de fluorescence normalisées, déterminées numériquement, aux courbes de titrations expérimentales, nous obtenons deux ensembles de résultats pour le coefficient de diffusion latéral, selon que l'association entre feuillets est autorisée ou pas. Nous utilisons un rayon de capture de 0.5 nm, la distance à partir de laquelle les deux sondes réagissent pour former un excimère. En comparant la dynamique Martini aux expériences de fluorescence, il est possible d'estimer le facteur d'accélérationWe propose a novel approach to extract the lateral diffusion coefficient in lipid bilayers using excimer formation. In contrast to previous statistical models that modeled the system as points undergoing jumps from site to site on a lattice, we use coarse-grained molecular dynamics to study lipid bilayers simulated using the Martini force field. We derive time dependent reaction rates from survival probabilities obtained a posteriori from numerically generated trajectories of symmetric DOPC (1,2-Dioleoyl-sn-glycero-3-phosphocholine) and POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) bilayers at 283K and 293K respectively. Collision dynamics are determined by virtually relabeling the simulated molecules. The fluorescent probes are assumed to behave like ordinary membrane lipids and therefore the dynamics remain unaffected. We derive a generalized expression for the survival probability combining independent pairs and size scaling assumptions, but no assumption is made regarding the kinetic rate of the excimer formation process. By fitting the numerically determined normalized fluorescence emission intensities to experimental titration curves, we obtain two sets of results for the lateral diffusion coefficients depending whether interleaflet excimer association is allowed or not. We use a capture radius of 0.5 nm, the distance at which the probes react to form excimers. By relating Martini dynamics to real fluorescence experiments, we estimate the numerical Martini acceleration factor. We also study mixtures of oxidized-non oxidized DOPC and POPC bilayers using a hydroperoxidized model of these lipids for different concentrations of the oxidized component (3.1%, 25% and 50%). Using pair correlation functions, we extract structural information on the systems and determine whether the two components are prone to mixing or not. Finally, we calculate the thermodynamic mixing parameters within the framework of the virial expansion
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Zöphel, Lukas Julian [Verfasser]. "Chemical transformations of the pyrene K-region for functional materials / Lukas Julian Zöphel". Mainz : Universitätsbibliothek Mainz, 2012. http://d-nb.info/1026397146/34.
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Crawford, Andrew. "Catalytic borylation of C-H bonds : a route to photophysically interesting pyrene derivatives". Thesis, Durham University, 2011. http://etheses.dur.ac.uk/663/.
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Pyrene derivatives have found use in a wide range of applications that make use of the unique structural, optical and charge-transfer properties of pyrene. Nearly all pyrene derivatives are substituted at the 1-, 3-, 6- and 8-positions, i.e. the sites of electrophilic aromatic substitution. In contrast, derivatives substituted at the 2- and 2,7-postions of pyrene are rare, as their syntheses involve laborious multistep processes. Such derivatives are of interest because they retain the long axis of symmetry and display unusual photophysical properties. Using the regiospecific direct C-H borylation of pyrene with an Ir-based catalyst, prepared in situ via reaction of [Ir(OMe)COD]2 with 4,4’-di-tert-butyl-2,2’-bipyridine, 2,7-bis(Bpin)pyrene 1 and 2-(Bpin)pyrene 2 (pin = OCMe2CMe2O) were synthesized. Straightforward derivatization strategies, converted 1 and 2 into nominally nucleophilic and electrophilic pyrene derivatives, which were further utilized in Suzuki-Miyaura, Sonogashira, Buchwald-Hartwig and Negishi cross-coupling reactions. Using this methodology, a library of 2- and 2,7-substituted pyrenes bearing donor and acceptor groups, including aryl, ethynyl, arylethynyl, alkyl, hydroxy, alkoxy, diarylamino, carboxylic acid and diarylboryl derivatives, was prepared. The solid-state structures of several derivatives obtained by single-crystal X-ray diffraction revealed a diverse range of structures and packing modes. The influence of the substitution position and the nature of the substituent upon pyrene was investigated in a detailed photophysical study. The existence of nodal planes passing through the 2- and 7-positions, perpendicular to the molecular plane, in both the HOMO and LUMO of pyrene accounts for the differing photophysical behaviour of derivatives substituted at 2- and 2,7-positions from those substituted at the 1-position. Finally, the applicability of iridium-catalysed C-H borylation and metal-catalyzed cross-coupling is further demonstrated on a range of interesting substrates.
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Bilash, О. М., О. М. Galaichenko, O. A. Sushko i M. M. Rozhitskii. "Benzo[a]pyrene its influence on human organism and new nanophotonic detection method". Thesis, Benzo[a]pyrene its influence on human organism and new nanophotonic detection method, 2011. http://openarchive.nure.ua/handle/document/8860.
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Benzo[a]pyrene (BaP) is representative of polycyclic aromatic hydrocarbons (PAHs) family, the substance of the first hazard class. In an environmental, BaP accumulates mainly in a soil and less in a water. It comes from soil to plants and human tissues and continues to move on in the food chain in living organisms where at each stage the BaP concentration is increasing sufficiently. To human organism BaP can come through skin, respiratory organs, digestive system and transplacental infections. Besides that BaP is the most typical chemical carcinogen in environmental, it is dangerous to humans even at low concentrations, since its metabolites are mutagenic and highly carcinogenic and has the property for bioaccumulation. Being chemically relatively stable, BaP can migrate for a long time from one object to another. As a result, many objects and process in the environmental objects which do not have the ability to synthesize the BaP, are the secondary sources of its production.
Content control of BaP in environmental can be accomplished by different assay among which the most wide-spread is liquid chromatography. Known methods possess both positive and negative characteristics the last are connected with assay complexity, not allowing of their used in a field conditions, duration, high cost. So new technologies especially based on nanotechnologies and nanomaterials are in great demand both for BaP and other hazardous organic PAHs compounds. Having in mind that BaP as most of PAH has high fluorescence yield in visible spectrum and is capable to emit electrogenerated chemiluminescence (ECL), it is quite possible to use this well-known assay method for both direct and indirect definition [1]. At the same time mentioned ECL methods of BaP definition provide not enough low limit of detection (LOD). Using luminescent nanomaterials such as semiconductor quantum dots (SCQD) as highly efficient detector elements in appropriate nanophotonic sensor can provide assay for BaP detection in surrounding objects water in the first turn with rather low LOD (10 nmol/l). The proposed combined photonic (electrochemiluminescent), nanotechnology (sensor’s electrode modification) and electrochemical (analytical signal excitation) techniques are possessing a number of advantages which are discussed in the given paper.
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Poon, Po Ying. "The cyto-protective effect of ginsenosides towards benzo[a]pyrene : induced-DNA damage". HKBU Institutional Repository, 2010. http://repository.hkbu.edu.hk/etd_ra/1231.
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Özbal, Can Cemil 1971. "Quantification of benzo[a]pyrene-diol-epoxide adducts by laser-induced fluorescence spectroscopy". Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9513.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Division of Bioengineering and Environmental Health, 1999.Includes bibliographical references.
Quantification of adducts in human samples is a challenging task in analytical chemistry. Humans are typically exposed to low levels of a wide range of different carcinogens. As a result, adduct quantification requires both a highly sensitive and a highly selective method. This project has focused on the development of new laser-induced fluorescence (LIF) based methods for the quantification of adducts in human samples. Two new instruments were built for LIF analysis. A cryogenic LIF instrument using a pulsed tunable dye laser as the excitation source was developed to obtain low temperature fluorescence emission spectra. A second instrument using a LIF detector interfaced to a HPLC separation system was developed to provide a higher level of selectivity than the cryogenic LIF system. The LIF instruments were used to quantify adducts of benzo[a]pyrene-7,8-diol-9,10- epoxide (BPDE) in human lung tissue and human bronchial epithelial cell histones and DNA and in human serum albumin. The presence of BPDE adducts in human lung tissue and human bronchial epithelial cell histones and DNA was proven by cryogenic fluorescence line-narrowing (FLN) spectroscopy. (-)-anti-BPDE-serum albumin adducts were quantified by HPLC-LIF in plasma obtained from 63 healthy volunteers. The method was shown to have a coefficient of variability of 22% and a detection limit of 20 attomoles of BPDE adduct. Adducts were detected in 60 of 63 samples (95%) at an average level of 0.22 femtomoles of adduct per mg of albumin. The investigation of histones as possible long-term molecular dosimeters was another focus in this research. The close proximity of histones and DNA coupled with the lack of repair and long lifetime make histones very attractive candidates as molecular dosimeters. The kinetics of histone turnover can most likely be accurately modeled by cellular turnover rates in vivo. Histone adducts were detected in human lung tissue and human bronchial epithelial cells. Histones were also shown to form adducts with BPDE, aflatoxin B1 (AFB,) and nitrosomethylurea (NMU) in TK6 cells grown in vitro. Histone adducts of AFB 1 , NMU, and BPDE were shown to be stable over 5 cell divisions.
by Can Cemil Özbal.
Ph.D.
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Kučerová, Petra. "Přenos energie ve studiu hydrofobních domén koloidních systémů". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2009. http://www.nusl.cz/ntk/nusl-216523.
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In this thesis resonance energy transfer between perylene and fluorescein in tetradecyltrimethylammonium bromide (TTAB) solution was studied. The influence of addition of native or modified sodium hyaluronate on resonance energy transfer was also investigated. The addition of native sodium hyaluronate supports energy transfer at lower fluorescein concentrations and the addition of modified sodium hyaluronate influences the maximal value of energy transfer effectivity. Strong influence on the critical micelle concentration (CMC) values with the addition of sodium hyaluronate during CMC of TTAB determination was investigated. The data indicates not only micelles formation, but also formation of aggregates of sodium hyaluronate with TTAB. Aggregation numbers of TTAB with addition of native and modified sodium hyaluronate by the quenching of pyrene by cetylpyridinium chloride (CPC) was investigated. The addition of sodium hyaluronate into the solution of TTAB changes the average mean aggregation number. Solute exchange between micelles of TTAB and the influence of addition of modified sodium hyaluronate on this exchange was also investigated. No solute exchange between micelles in TTAB and in TTAB with added modified sodium hyaluronate was discovered during this experiment.
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Neesu, Rachana. "Fused Arene-Based Molecular Systems as Additives for Organic Photovoltaics". TopSCHOLAR®, 2015. http://digitalcommons.wku.edu/theses/1471.
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Organic photovoltaics (OPVs) are mainly based on organic semiconducting small molecules, macromolecules, and polymers, which form an active layer in photovoltaics. They act as an active material in absorbing light and causing charge mobility to generate electricity from sunlight. This thesis describes the molecular systems derived from fused arenes such as anthracene, pyrene, carbazole and thiophene for use as either a donor or an acceptor component of the active layer of OPVs. Two novel molecular systems (9- anthracenecarboxy-1-methylpyrene, (1) and Py-bi-TH-ANT, (2) were prepared using Steglich esterification and Grignard metathesis followed by Kumada coupling. The molecular structure of each was confirmed by 1H-NMR and IR analysis respectively. The photophysical properties of the products were also evaluated in solution. The potential applicability of these two novel systems for OPVs will be studied in the future.
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Baldi, Leonardo Dela Coleta. "Avaliação da polaridade superficial de nailons por espectroscopia de fluorescencia". [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249452.
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Orientador: Teresa D. Z. AtvarsDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Mestrado
Físico-Química
Mestre em Química
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Serpi, R. (Raisa). "Mechanism of benzo(a)pyrene-induced accumulation of p53 tumour suppressor protein in mouse". Doctoral thesis, University of Oulu, 2003. http://urn.fi/urn:isbn:9514270398.
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Abstract
The tumour suppressor gene TP53 is the most commonly mutated gene in human cancers. The protein it codes, p53, becomes activated as a response to stress signals. When activated, p53 binds to DNA and affects the transcription of its target genes. They then cause cell cycle arrest, DNA repair and/or induction of programmed cell death, thus preventing mutations and cancer. Specific mutations in TP53 are associated with exposure to certain carcinogens, such as polycyclic aromatic hydrocarbons (PAHs). These environmental chemical carcinogens are formed through incomplete combustion of organic material. Benzo(a)pyrene (BP) is commonly used as a model compound for PAH carcinogenesis. BP causes accumulation of p53, but the mechanism of accumulation is not known. The aim of this study was to gain more insight into the p53 protein in the first phases of PAH carcinogenesis in vivo in mouse, using BP as the model compound.
Mice from the inbred C57BL/6 strain were treated topically or intraperitoneally with BP or were exposed to cigarette smoke inhalation. The amount of p53 protein was studied by immunoblotting, immunohistochemistry and immuno electron microscopy, and the mdm2, p21 and p19ARF proteins were studied by immunoblotting. The binding of BP to DNA was measured by synchronous fluorescence spectrophotometry.
The p53 protein was induced in vivo in skin and lung after BP treatment and in lung after cigarette smoke treatment. An increase in p53 was associated with an increase in the amount of BP-DNA adducts. In skin, the induction of p53 was accompanied by induction of the p21 and mdm2 proteins, which are transcriptional targets of p53. This indicates that the in vivo induced p53 is a wild-type protein and functional. In lungs, the induction of p53 was accompanied by a decrease of mdm2 and an increase of p19ARF. These results confirm that BP is metabolized and binds to DNA in mouse tissues and indicate that BP-DNA adducts are the trigger for p53 protein induction. The in vivo regulation of the p53 protein is different in different tissues of C57BL/6 mouse.
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Costa, Telma Sofia Martins. "Photophysics of macromolecular pyrene-containing systems". Doctoral thesis, 2009. http://hdl.handle.net/10316/9622.
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Su, Chun Hsien, i 蘇俊憲. "Pyrene Based Initiator in Photo-induced ATRP and Persistently Enhanced Fluorescence Observed from Poly(styrene) with Pyrene Chromophore". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/01861654838819565291.
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碩士國立清華大學
化學系
103
Chromophoric initiator containing pyrene moiety was synthesized and was used to the normal and photo-induced ATRP of various monomers to obtain the flourscent polymer. These well-controlled dye-labeled polymer showed a low polydispersity (Mw / Mn = 1.20 ~ 1.30), and could form the diblock copolymers. Photo-induced or Photo-mediated ATRP was performed in our study. Photo-induced ATRP is an efficient or economical method for methyl acrylate, methyl methacrylate and styrene polymerization. The photo-mediated polymerization could use the handheld UV light as the low energy source to replace the traditional oil bath or the high temperature condition. Besides, during the photo-induced ATRP process we found the poly(styrene) had the strongest fluorescence than other polymers. For this reason, we compared the fluorescence of dye-labeled polymer by ATRP and photo-induced ATRP. Moreover we designed some control experiments to illustrate and explain the strongly fluorescent effect in poly(styrene) by photo-induced ATRP. Meanwhile, we used the homo or diblock copolymer with chromophore to form the nanotube polymer structure by AAO (anodic aluminum oxide) template. The nanotube structure could be observed by the SEM (Scanning electron microscopy) and the fluorescence of nanotube polymer structure was also discussed.
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Hsieh, Yun-chu, i 謝雲竹. "Phytoremediation of PAHs(pyrene) Contaminated Soils through mangroves". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/q2ep2f.
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碩士國立中山大學
海洋環境及工程學系研究所
96
In this study,we used mangrove phytoremediation ecotechniques to treat polycyclic aromtic hydrocarbons (pyrene) contaminated soil. First, we compared the four species of mangroves in Taiwan, Kandelia candel Druce, Rhizophora stylosa Griff, Avicennia marina Vierh and Lumnitzera racemosa Willd, inoculated by endomycorrhizae in no contaminated soils. According to the experimental results, the four species of mangroves could be colonized by Glomus aggregatum and Glomus mosseae. In colonization rate and colonization intensity, Glomus aggregatum were found higher than those of Glomus mosseae. For the degradation efficiencies of pyrene in soils, according to the experimental results, we found that the Lumnitzera racemosa Willd exhibited best growing conditions among the four species. The degradation rates for all tests systems pyrene were measured above 90% . In accordance with passed study, the species of Kandelia candel Druce presented effective efficiencics for pyrene degradation. The speacis of Lumnitzera racemosa Willd and Kandelia candel Druce were planted in the artifical pyrene contaminated soils, which were incubated in a greenhouse , while the control systems without vegetation were used for comparison. After 90 days of incubation, the experimental result showed that the soils planted with Lumnitzera racemosa Willd and Kandelia candel Druce were found able to enhance the microbial and dehydrogenase activities. The addition of Glomus aggregatum could help plants to prevent from the stress of pyrene. The addition of salinity into the siols was a pressure for mangroves so the mangroves, incoculated by endomycorrhizae showed stronger dependence on mycorrhizal fungi than those in the siols of no salinity. In salty siol, mangroves exhibited high effective degradation rates for pyrene. In the siols for the illumination groups, the pyrene degradation rates for all test systems were measured about 85%. The siols for the dark groups showed that the average pyrene degradation rates were about 70%.
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Chang, Yi Chih, i 張益銍. "Molecular Mechanism Studies of Benzo(a)pyrene Carcinogenesis". Thesis, 1999. http://ndltd.ncl.edu.tw/handle/35098957245627872584.
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碩士國立陽明大學
醫學生物技術研究所
87
Abstract Benzo(a)pyrene( B(a)P ) is a kind of environmental pollutants that commonly exists in our circumstance. It has been shown that B(a)P is carcinogenic in many researches of genotoxicities and experimental animals , but the underlying mechanism is still not clear. To surmise the possible molecular mechanisms, we studied the effects of B(a)P on the molecules in cytoplasm ( protein kinase C ) and nucleus ( proto-oncogene : c-jun , c-fos ) , individually , and B(a)P's transformation ability by performing doubling time , saturation density , transformation assays. From the doubling time and saturation density tests , we found that the cells doubling time was shortened and its saturation density was increased when the cells were treated with B(a)P (1-5 uM). Combined treatment of both B(a)P and the well known tumor promotor 12-o-tetradecanoyl phorbol 13-acetate (TPA) enhanced these observed phenomena. In cell transformation test , we observed that treatment of B(a)P alone transformed cells to foci formation. Its transformation ability was not as good as the well-known carrcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) , but better than TPA. If B(a)P was combined with TPA , the transformation ability was similar to positive control (MNNG+TPA). These results suggested that B(a)P could play a role as an initiator but not promotor during cell transformation. Protein kinase C (PKC) is pivotal in intracellular signal transduction, Therefore we analyzed B(a)P's effect on PKC translocation. From western blot results , B(a)P did not affect PKC-αandδisoform translocation. As we known , c-Jun and c-Fos are proteins that accelerate the processing of cell cycle. From northern blot analysis , B(a)P did not have significant effect on c-jun and c-fos expression. In summary , our data suggest that B(a)P may alter some events related to cell growth but not via PKC signal transduction and c-jun and c-fos expression. During carcinogenesis , B(a)P causes cell transformation and may play a role as an initiator.
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Hu, Hsiao-Yun, i 胡曉雲. "Studies on the Phytoremediation of Pyrene Contaminated Soils". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/52927547311263973055.
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碩士朝陽科技大學
環境工程與管理系碩士班
96
Polycyclic Aromatic the Hydrocarbons contamination concern has received takes seriously, PAHs was confirmed that surpasses several hundred derivatives has the carcinogenicity and causes the sudden change. At present improvement of processing PAHs often transforms into regarding the soil in the extract way, but transforms into the method to be able only to each interaction transformation, Following still needed - step by other technical processing, moreover also possibly destroys the local ecology resources. In recent years studied the discovery use plant cicada chrysalis to be possible in-situ repair soil of the organic matter pollution. In this study, as supply take alluvial soils and red soils was used for experiment which are the main category soil for farming in Taiwan, the quartz sand take the control group, and Pyrene was spiked into soils to simulate the contaminated soils, the use pot experiment planter Bermuda grass and Medicago sativa. Pyrene of contaminated soil in the different density, increases 5% raise earth separately, the test Bermuda grass and Medicago sativa to the soil in degeneration of effect the Pyrene. The result showed that increases 5% raise earth in the Pyrene density is 100 mg kg-1,200 mg kg-1,300 mg kg-1,400 mg kg-1, of contaminated quartz sand in 500 mg kg-1, the Medicago sativa to the Pyrene degeneration rate respectively is 73.3%, 58.1%, 49.7%, 37.7%, 30.6%. But increases 5% raise earth in the Pyrene density is 50 mg kg-1,100 mg kg-1,150 mg kg-1, of contaminated quartz sand in 200 mg kg-1 the Pyrene degeneration rate respectively is 74.7%, 65.7%, 57.2%, 51.7%. The result showed that contaminated quartz sand in 50 mg kg-1, the Medicago sativa to the Pyrene degeneration rate respectively is 74.7%, Therefore if the suggestion plants by the Bermuda grass and Medicago sativa lives cicada chrysalis processing the Pyrene contaminated soil, its soil increases 5% raise earth to be possible to promote degeneration of effect effectively the pollutant.