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Vestlund, Hanne. "Development of a Method for GC/MS Analysis of PAHs and Alkylated PAHs for Use in Characterization and Source Identification of PAH Contaminated Sites." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-42008.
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Polycyclic aromatic hydrocarbons (PAHs) are toxic and carcinogenic environmental contaminants originating from different sources; petrogenic, pyrogenic or biogenic. Depending on the source of contamination there will be different ratios of PAHs and the effects on the environment will differ. Petrogenic sources will be higher in concentration of alkyl substituted PAHs (APAHs) while pyrogenic sources will be higher in parent PAHs. In the present study a GC/MS method was developed to separate and calibrate PAHs, dibenzothiophenes and alkyl substituted PAHs in a mix containing 49 standards. The method was able to differentiate between PAHs and APAHs with the same mass number; up to six different compounds with the same mass number was separated. The developed method was used to analyse six different soil samples from various contamination sites. PAHs, APAHs and dibenzothiophenes were identified and quantified in all samples. In order to establish the source of contamination, the distribution pattern, the ratio between different PAHs, and the ratio between APAHs and parent PAHs were used. There was a higher ratio of APAHs/PAHs and a lower ratio between the parent PAHs in the soil samples from sites contaminated with oils compared to the other samples, indicating petrogenic source.Polycykliska aromatiska kolväten (PAH) är giftiga och cancerframkallande miljögifter som härstammar från olika källor; petrogena, pyrogena eller biogena. Olika föroreningskällor kommer att ha olika förhållanden av PAH och effekterna på miljön kommer att skilja. Petrogena källor innehåller högre koncentrationer av alkylsubstituerade PAH (APAH) medan pyrogena källor kommer att ha högre koncentration av PAH. I denna studie har en GC/MS-metod utvecklats för att separera och kalibrera PAH, dibensotiofener och alkylsubstituerade PAH i en blandning innehållande 49 standarder. Metoden kunde skilja mellan PAH och alkylsubstituerade PAH med samma masstal; upp till sex olika föreningar med samma masstal särskildes. Den utvecklade metoden användes för att analysera sex olika jordprover från olika föroreningsplatser. PAH, APAH och dibensotiofener identifierades och kvantifieras i samtliga prover. För att fastställa föroreningskällan användes fördelningsmönstret för APAH och PAH, förhållandet mellan olika PAH och ration mellan APAH och PAH. Det fanns en högre kvot APAH/PAH i jordprover från områden som var förorenade med olja, vilket indikerar på petrogena föroreningskällor.
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Diédhiou, Malick. "Ion Chemistry of Hydrogenated PAHs." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/40452.
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Polycyclic aromatic hydrocarbons (PAHs) are a class of organic molecules suggested to constitute roughly 20% of carbon in the interstellar medium (ISM). These species exist in both neutral and ionic forms and both are potentially involved in processes such as H2 formation. Catalyzing H2 formation necessarily involves the participation of hydrogenated PAHs as reaction intermediates. Employing tandem mass spectrometry and imaging photoelectron photoion coincidence spectroscopy and theory, we have explored the unimolecular reactions of five ionized hydrogenated PAHs that vary in degree and position of hydrogenation: tetralin (1,2,3,4-tetrahydronaphthalene), 9,10-dihydroanthracene (DHA+•), 1,2,3,4-tetra- and 1,2,3,4,9,10-hexa-hydrophenanthrene (THP+• and HHP+•) and 1,2,3,4,5,6,7,8-octahydroanthracene (OHA+•). The major reactions observed were the losses of the hydrocarbons CH3•, C2H4 and C3H5• together with H• atom loss. RRKM modeling of the iPEPICO data suggested that the unimolecular chemistries were based around a two-well potential energy surface in each case. Ionized tetralin can lose all four neutrals via H-shift and ring-opening reactions, or CH3• and C2H4 after interconversion to the 1-methylindane ion, a process similar to that found for ionized 1,2-dihydronaphthalene (isomerizing to form the 1-methylindene ion structure). DHA+• exhibits the same reactions previously observed for 1,2-dihydronaphthalene and 9,10-dihydrophenanthrene, namely competing loss of H• and CH3•. However, the energy required for H•-loss, as predicted by RRKM modeling of the iPEPICO results, was lower than the latter ions, presumably due to an expansion of the electron delocalization across the central ring upon dehydrogenation. OHA+• behaves similarly to ionized tetralin, displaying losses of H•, CH3•, C2H4 and C3H5• in its collision induced dissociation (CID) mass spectra, but under iPEPICO conditions CH3•-loss is not observed. THP+•
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and HHP+• have aspects of both DHA+• and OHA+• chemistries, displaying losses of H•, CH3•, C2H4 and C3H5•. Minimum energies for all observed reaction channels were thus obtained, together with selected mechanisms computationally explored at the B3-LYP/6-31+G(d,p) level of theory. The trend in reactivity in going from tetralin and DHA+• to THP+•, HHP+• and ultimately OHA+• sees decreasing abundance of H• and CH3•-loss and an increasing dominance of the formation of C2H4, C3H5• and higher hydrocarbons with degree of hydrogenation as isomerization to a methyl-substituted ion becomes less significant. As this isomerization decreases in significance, the ions become sources of small hydrocarbon molecules and not hydrogen atoms or molecules.
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Wanene, Wilson Kamau. "Toward curved polycyclic aromatic hydrocarbons (PAHs)." abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1445914.
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Herwijnen, René van. "Metabolic and cometabolic biodegradation of PAHs." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2003. http://dare.uva.nl/document/87041.
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Castaldini, Francesca. "Bioremediation of PAHs - Limitations and soultions." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amslaurea.unibo.it/130/.
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Introduction
1.1 Occurrence of polycyclic aromatic hydrocarbons (PAH) in the environment
Worldwide industrial and agricultural developments have released a large number of natural and synthetic hazardous compounds into the environment due to careless waste disposal, illegal waste dumping and accidental spills. As a result, there are numerous sites in the world that require cleanup of soils and groundwater.
Polycyclic aromatic hydrocarbons (PAHs) are one of the major groups of these contaminants (Da Silva et al., 2003). PAHs constitute a diverse class of organic compounds consisting of two or more aromatic rings with various structural configurations (Prabhu and Phale, 2003). Being a derivative of benzene, PAHs are thermodynamically stable. In addition, these chemicals tend to adhere to particle surfaces, such as soils, because of their low water solubility and strong hydrophobicity, and this results in greater persistence under natural conditions. This persistence coupled with their potential carcinogenicity makes PAHs problematic environmental contaminants (Cerniglia, 1992; Sutherland, 1992). PAHs are widely found in high concentrations at many industrial sites, particularly those associated with petroleum, gas production and wood preserving industries (Wilson and Jones, 1993).
1.2 Remediation technologies
Conventional techniques used for the remediation of soil polluted with organic contaminants include excavation of the contaminated soil and disposal to a landfill or capping - containment - of the contaminated areas of a site. These methods have some drawbacks.
The first method simply moves the contamination elsewhere and may create significant risks in the excavation, handling and transport of hazardous material. Additionally, it is very difficult and increasingly expensive to find new landfill sites for the final disposal of the material. The cap and containment method is only an interim solution since the contamination remains on site, requiring monitoring and maintenance of the isolation barriers long into the future, with all the associated costs and potential liability.
A better approach than these traditional methods is to completely destroy the pollutants, if possible, or transform them into harmless substances. Some technologies that have been used are high-temperature incineration and various types of chemical decomposition (for example, base-catalyzed dechlorination, UV oxidation).
However, these methods have significant disadvantages, principally their technological complexity, high cost , and the lack of public acceptance. Bioremediation, on the contrast, is a promising option for the complete removal and destruction of contaminants.
1.3 Bioremediation of PAH contaminated soil & groundwater
Bioremediation is the use of living organisms, primarily microorganisms, to degrade or detoxify hazardous wastes into harmless substances such as carbon dioxide, water and cell biomass Most PAHs are biodegradable unter natural conditions (Da Silva et al., 2003; Meysami and Baheri, 2003) and bioremediation for cleanup of PAH wastes has been extensively studied at both laboratory and commercial levels- It has been implemented at a number of contaminated sites, including the cleanup of the Exxon Valdez oil spill in Prince William Sound, Alaska in 1989, the Mega Borg spill off the Texas coast in 1990 and the Burgan Oil Field, Kuwait in 1994 (Purwaningsih, 2002).
Different strategies for PAH bioremediation, such as in situ , ex situ or on site bioremediation were developed in recent years. In situ bioremediation is a technique that is applied to soil and groundwater at the site without removing the contaminated soil or groundwater, based on the provision of optimum conditions for microbiological contaminant breakdown.. Ex situ bioremediation of PAHs, on the other hand, is a technique applied to soil and groundwater which has been removed from the site via excavation (soil) or pumping (water). Hazardous contaminants are converted in controlled bioreactors into harmless compounds in an efficient manner.
1.4 Bioavailability of PAH in the subsurface
Frequently, PAH contamination in the environment is occurs as contaminants that are sorbed onto soilparticles rather than in phase (NAPL, non aqueous phase liquids). It is known that the biodegradation rate of most PAHs sorbed onto soil is far lower than rates measured in solution cultures of microorganisms with pure solid pollutants (Alexander and Scow, 1989; Hamaker, 1972). It is generally believed that only that fraction of PAHs dissolved in the solution can be metabolized by microorganisms in soil. The amount of contaminant that can be readily taken up and degraded by microorganisms is defined as bioavailability (Bosma et al., 1997; Maier, 2000).
Two phenomena have been suggested to cause the low bioavailability of PAHs in soil (Danielsson, 2000).
The first one is strong adsorption of the contaminants to the soil constituents which then leads to very slow release rates of contaminants to the aqueous phase. Sorption is often well correlated with soil organic matter content (Means, 1980) and significantly reduces biodegradation (Manilal and Alexander, 1991). The second phenomenon is slow mass transfer of pollutants, such as pore diffusion in the soil aggregates or diffusion in the organic matter in the soil. The complex set of these physical, chemical and biological processes is schematically illustrated in Figure 1.
As shown in Figure 1, biodegradation processes are taking place in the soil solution while diffusion processes occur in the narrow pores in and between soil aggregates (Danielsson, 2000).
Seemingly contradictory studies can be found in the literature that indicate the rate and final extent of metabolism may be either lower or higher for sorbed PAHs by soil than those for pure PAHs (Van Loosdrecht et al., 1990). These contrasting results demonstrate that the bioavailability of organic contaminants sorbed onto soil is far from being well understood.
Besides bioavailability, there are several other factors influencing the rate and extent of biodegradation of PAHs in soil including microbial population characteristics, physical and chemical properties of PAHs and environmental factors (temperature, moisture, pH, degree of contamination).
Figure 1: Schematic diagram showing possible rate-limiting processes during bioremediation of hydrophobic organic contaminants in a contaminated soil-water system (not to scale) (Danielsson, 2000).
1.5 Increasing the bioavailability of PAH in soil
Attempts to improve the biodegradation of PAHs in soil by increasing their bioavailability include the use of surfactants , solvents or solubility enhancers.. However, introduction of synthetic surfactant may result in the addition of one more pollutant. (Wang and Brusseau, 1993).A study conducted by Mulder et al. showed that the introduction of hydropropyl-ß-cyclodextrin (HPCD), a well-known PAH solubility enhancer, significantly increased the solubilization of PAHs although it did not improve the biodegradation rate of PAHs (Mulder et al., 1998), indicating that further research is required in order to develop a feasible and efficient remediation method.
Enhancing the extent of PAHs mass transfer from the soil phase to the liquid might prove an efficient and environmentally low-risk alternative way of addressing the problem of slow PAH biodegradation in soil.
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Wang, Yu. "Development and application of a solidphase extraction method for simultaneousdetermination of PAHs, oxy-PAHs andazaarenes in water samples." Thesis, Umeå universitet, Kemiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-56332.
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In this study, a solid phase extraction (SPE) method was developed that can be used to extract a wide range of polycyclic aromatic compounds (PACs), including polycyclic aromatic hydrocarbons (PAHs), oxygenated PAHs (oxy-PAHs) and azaarenes, from water samples. Three commercially available SPE materials, i.e. Oasis HLB, ISOLUTE C2/C18 (EC) and ISOLUTE PAH, were tested for their capability to accomplish the extraction, and two were chosen for further optimization. Several different combinations of solvents were tested. Experiments were performed on both spiked and real contaminated water samples. The ISOLUTE C2/C18 (EC) performed best on spiked samples for most of the target PACs while the Oasis HLB material was more suitable for real samples. The results from both materials agreed well with the results obtained with a traditional method based on liquid-liquid extraction (LLE) followed by silica gel fractionation. The final method was based on Oasis HLB eluted with dichloromethane/ methanol (7:3) using a flow rate not exceeding 2ml/min. This method was applied on ten real samples collected from a water treatment plant operating at a creosote contaminated wood preservation site in order to exam how much the dissolved concentrations of target PACs varied in the plant. The SPE method is faster and consumes much less solvent than a method based on LLE for instance and it is also less labor intensive. The SPE method is therefore favorable during larger studies on PACs contamination in aqueous environments.
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LeÌrida, Laura Cano. "New synthetic receptors for sensors for PAHs." Thesis, University of York, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433998.
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Karlsson, Elin. "Förekomst av polycykliska aromatiska kolväten (PAHer) i vilda och odlade blåmusslor." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-45457.
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I denna studie har förekomst av Polycykliska aromatiska kolväten (PAHer) i musslor undersökts. Syftet var att undersöka vilka PAHer som förekom, i vilka halter och ifall dessa nivåer överskred gränsvärdena för humankonsumtion. Vissa PAHer är skadliga för människan då de kan ge upphov till cancer. Vilda och odlade musslor jämfördes för att se om innehållet av PAHer skiljde sig åt. Musslor från sex olika provplatser undersöktes. Två prov handplockades vilda utanför Stenungssund, Sverige. Danska vildfångade musslor undersöktes, likaså vildfångade svenska musslor. Även odlade musslor från Irland och odlade musslor från Sverige undersöktes. Resultaten visar att fluoranten, fenantren, pyren, krysen, benzo(e)pyren och benzo(b)fluoranten var de ämnen som förekom i högst halter. Av de alkylerade PAHerna var 2-metylantracen-9,10-dion, 2-metylfenantren, 2-metylkrysen och 1-metylfluoranten vanligast. Halterna av oxy-PAHer var låga, förutom för antracen-9,10-dion, benzo(h)quinolin samt 2-metylantracen-9,10-dion. Utifrån de riktvärden som finns för humankonsumtion överskred inga musslor gränsvärdena. Inga skillnader kunde ses mellan odlade och vilda musslor. Sammanfattningsvis förekommer PAHer i musslor, men inte i sådan halt att musslorna inte är godkända som livsmedel.In this study, the presence of PAHs in mussels were investigated. The aim was to examine the occurrence of PAHs, at which levels and if these levels exceeded the limits for human consumption. Some PAHs are toxic to humans as they can give rise to cancer. Wild and cultivated mussels were compared to see if the content of PAHs was different. Mussels from six different test sites were examined. Two wild samples were hand-picked outside Stenungsund, Sweden. Furthermore, wild clams from both Sweden and Denmark were sampled. Also cultured mussels from Ireland and cultured mussels from Sweden were investigated. The results show that fluoranthene, phenanthrene, pyrene, chrysene, benzo(e)pyrene and benzo(b)fluoranthene were the compounds that occurred at the highest levels. The most common alkylated PAHs were 2-methylanthracene-9,10-dione, 2-methylphenanthrene, 2-methylchrysene and 1-methylfluoranthene. The concentrations of oxy-PAHs were low except for anthracene-9,10-dione, benzo(h)quinoline and 2-methylanthracene-9,10-dione. Based on the guideline values available for human consumption, no mussels exceeded the limits. No differences could be seen between wild and cultivated mussels. To sum up, PAHs were found in mussels, but not at such concentration that the mussels would not be approved for human consumption.
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Petry, Thomas. "Human exposure to airborne polycyclic aromatic hydrocarbons (PAHs) /." [S.l.] : [s.n.], 1994. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10726.
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Bukvic, Anamaria. "Phytoremediation of Metals and PAHs Occurring as Mixtures." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1016463095.
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Smith, Erin Caitriona. "Investigation of PAHs in planetary nebulae using FLITECAM." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1619452341&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Li, Zheng. "Characterization of Polycyclic Aromatic Hydrocarbons (PAH) in airborne particles and assessment of human exposure to PAHs." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28122.
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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2009.Committee Chair: Mulholland, James A.; Committee Member: Bergin, Michael H.; Committee Member: Patterson Jr., Donald G.; Committee Member: Russell, Armistead G.; Committee Member: Sjodin, Andreas; Committee Member: Wine, Paul H.
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Long, Rachel May. "The distribution and diversity of PAC-degrading bacteria and key degradative genes." Thesis, University of Exeter, 2008. http://hdl.handle.net/10036/65303.
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Petroleum hydrocarbons are the most widespread contaminants in the environment. Interest in the biodegradation of polycyclic aromatic hydrocarbons and compounds (PAHs/PACs) is motivated by their ubiquitous distribution, their low bioavailability, high persistence in soils and their potentially deleterious effects to human health. Identifying the diversity of microorganisms that degrade PAHs/PACs can be utilised in the development of bioremediation techniques. Understanding the mechanisms of bacterial populations to adapt to the presence of pollutants and the extent that lateral transfer of key functional genes occurs, will allow the exploitation of microbial PAC/PAH-degradative capabilities and therefore enhance the successful application of bioremediation strategies. A key aim of this study was to isolate and identify PAC-degrading bacteria for potential use in future bioremediation programmes. A series of PAC enrichments were established under the same experimental conditions from a single sediment sample taken from a highly polluted estuarine site. Distinct microbial community shifts were directly attributable to enrichment with different PAC substrates. The findings of this study demonstrate that five divisions of the Proteobacteria and Actinobacteria can degrade PACs. By determining the precise identity of the PAC-degrading bacteria isolated, and by comparing these with previously published research, this study showed how bacteria with similar PAC degrading capabilities and 16S rRNA signatures are found in similarly polluted environments in geographically very distant locations e.g. China, Italy, Japan and Hawaii. Such a finding suggests that geographical barriers do not limit the distribution of key PAC-degrading bacteria. This is significant when considering the diversity and global distribution of microbes with PAC-degradative capabilities and the potential for utilising these microbial populations in future bioremediation strategies. In the laboratory, enrichment of bacteria able to utilise PAHs has commonly been performed in liquid media, with the PAH dissolved in a carrier solvent. This study found the presence of a carrier solvent significantly affects the resultant microbial population. Although the same sediment sample was used as the bacterial source in all enrichments, different bacterial strains were obtained depending upon the presence of the carrier solvent and the PAH. This is important when considering appropriate methodology for the isolation of PAH-degrading bacteria for future bioremediation programmes. Additionally, the species comprising the resultant population of the enrichment when a carrier solvent was present were similar to previously reported PAH-degrading species. Such a finding necessitates review of previously reported PAH-degrading bacterial species that have been isolated and identified from enrichments using a carrier solvent. Understanding how bacteria acclimatise to environmental pollutants is vital for exploiting these mechanisms within clear up strategies of contaminated sites. Two major lineages of the α subunit of PAH dioxygenases were identified: Actinobacteria and Proteobacteria. Comparison of the α subunit phylogeny with the 16S rRNA phylogeny implies that the PAH-dioxygenases evolved prior to the separation of these phyla or that lateral transfer occurred in the very distant past. No evidence for lateral transfer of the α subunit between the Actinobacteria and Proteobacteria was found in the phylogenetic analyses of this research. Multiple lateral transfer events were inferred between the species of the Actinobacteria and between the classes of the Proteobacteria. The clustering of the taxa within the α subunit phylogeny indicates that lateral transfer of the α subunit gene occurred after the separation of the classes of Proteobacteria and also after the speciation of the γ-Proteobacteria. These findings reveal how bacteria have acclimatised to PAH pollutants through multiple lateral transfer events of a key PAH-degradative gene. This knowledge of the transfer of genetic material will broaden our prospects of exploiting microbial populations.
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Gomez, Katherine Emma. "Phytoremediation of contaminated soil from a petroleum refinery land treatment unit." Cincinnati, Ohio : University of Cincinnati, 2001. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=ucin1006197725.
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Szücs, Rózsa. "Phosphorus modified PAHs : tunable π-systems for optoelectronic applications." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1S022/document.
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Les Hydrocarbures Polycycliques Aromatiques (abréviés PAHs en anglais) sont des synthons importants du point de vue expérimental et théorique en raison de leurs potentielles applications dans des dispositifs optoélectroniques tels que les diodes électroluminescentes organiques, les cellules solaires ou les transistors à effet de champs. Les propriétés des PAHs peuvent être modifiées par l'insertion d'hétéroatomes dans le squelette carboné sp2. Cependant, les exemples de PAHs modifiés par un atome de P sont très rares. Nous avons démontré expérimentalement et théoriquement que l'insertion d'un atome de P en périphérie du PAH a un impact important sur la structure électronique de l'ensemble du système π-étendu, comme le montre l'étude des orbitales frontières HO (Haute Occupée) et BV (Basse Vacante). Ces deux orbitales moléculaires gardent les caractéristiques spatiales du phosphole parent. Cependant l'écart HO-BV est fortement diminué en raison de l'interaction du phosphole et du système π-conjugué bidimensionnel. En effet, la densité électronique est délocalisée sur l'ensemble de la structure carbonée. L'effet de la modification chimique de l'atome de P (dont la complexation par des métaux de transition) sur les propriétés électroniques a été étudié et il a été démontré qu'elle permet de modifier finement les propriétés optiques. L'aromaticité est également un paramètre fondamental des systèmes π-conjugués (poly)cycliques. L'aromaticité locale de chaque cycle des PAHs a été étudiée grâce au calcul du paramètre NICS(1). La modification de l'aromaticité locale de l'hétérocycle à 5 chainons (par variation de l'hétéroatome) a un fort impact sur l'aromaticité locale des cycles adjacents. Il a également été montré que la cyclo-addition sur les PAHs phosphorés a lieu sur l'hétérocycle de plus faible aromaticité et permet de préparer des PAHs inéditsPolycyclic aromatic hydrocarbons (PAHs) are important targets of experimental and theoretical studies, because of their potential use in optical and electronic devices, such as light-emitting diodes, field-effect transistors or photovoltaics. The properties of PAH systems can be modified by embedding heteroatoms into the sp2 backbone, however for P-modified PAHs, only a few examples exist. During my PhD research, I studied the properties of P-containing extended π-systems. It has been revealed by density functional calculations that the incorporation of phosphorus at the edge position of a PAH has a significant effect on the electronic structure of the entire π-system, as can be seen through the HOMO and LUMO. On the one hand, both orbitals keep the spatial characteristics of the parent heterocycle, on the other hand, the reduced HOMO-LUMO gap compared to the parent heterocycle is a consequence of the interaction between the phosphole unit and the extended aromatic system, as the molecular orbitals are delocalized through the sp2 carbon skeleton. We investigated the effect of chemical modification (including complexation) at the phosphorus atom, and found that due to the variation of the hyperconjugative interaction it can be used to fine-tune the optical properties. Aromaticity is one of the key characteristics of π-systems. During its investigation we have established that the local aromaticities in the investigated ring system could be best described by the NICS(1) values. The modification of the local aromaticity of the five-membered ring (by the variation of the heteroatom) has a significant impact on the local aromaticities of some of the other rings as well. It has been shown that the Diels-Alder cycloaddition of the P-embedded PAHs proceeds at those rings which exhibit the lowest aromaticity
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Bugg, Trevor. "Uptake and efflux of PAHs across bacterial cell membranes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0008/MQ60096.pdf.
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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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Ives, Sian E. "The biodegradation of polycyclic aromatic hydrocarbons (PAHs) in groundwater." Thesis, University of Huddersfield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368319.
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Cooke, Andrew Ralph. "The high quality monitoring of PAHs in potable waters." Thesis, University of Bristol, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336869.
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Aquino, Theodore. "Comparison of Urinary PAHs among Firefighters and Asphalt Pavers." Thesis, University of South Florida, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10103851.
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Firefighters and asphalt pavers are exposed to polycyclic aromatic hydrocarbons (PAHs) during various work activities. The purpose of this study was to evaluate urinary PAH levels and compare these bio-monitoring levels among firefighters, asphalt pavers, and non-occupationally exposed individuals. The National Institute of Standards and Technology (NIST) urinary PAH levels were used for non-occupationally exposed controls. When compared to the NIST standard for smokers and non-smokers, firefighters demonstrated statistically significant differences in urinary concentration differences for the following metabolites: 2-OH-fluorene, 3-OH-fluorene and 1-OH-pyrene, which were lower in firefighters than the NIST mean for smokers. 1-OHphenanthrene, 2-OH-phenanthrene and 3-OH-phenanthrene were higher among world trade center exposed firefighters than the NIST mean for smokers. When firefighters were compared to the NIST non-smoker standard, firefighters demonstrated elevated levels in all tested PAH biomarkers due to a mixture of smokers and non-smokers in the firefighter cohort.
Asphalt workers had statistically significant higher urinary concentration elevations in 2OH-fluorene, 1-OH-phenanthrene and 3-OH-phenanthrene as compared to the NIST smoker mean. When asphalt pavers were compared to the NIST non-smoker mean, asphalt pavers had statistically significant increases in all tested PAH biomarkers, with the exception of 2-OHphenanthrene. While firefighters did not demonstrate a substantial change in urinary PAH metabolite levels compared to control populations of smokers and non-smokers, asphalt pavers experienced concentrations that were in some cases increased by orders of magnitude compare to NIST controls. Future research may be needed to evaluate any potential health risk posted to occupational exposed asphalt pavers.
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Oliveira, Vera Lúcia Henriques de. "Modelling the aqueous solubility of PAHs with CPA EoS." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/3019.
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Mestrado em Engenharia QuímicaOs hidrocarbonetos aromáticos policíclicos (PAHs) constituem uma família de compostos caracterizada por possuírem dois ou mais anéis aromáticos condensados. São no geral referenciados de contaminantes ambientais porque estão associados à combustão incompleta de materiais orgânicos, como por exemplo, a queima de combustíveis fosseis, incineração de resíduos e derrames de petróleo. O estudo da solubilidade destes compostos em misturas aquosas é de grande importância, devido ao impacto que estes compostos têm na saúde pública e no meio ambiente, dado as suas propriedades cancerígenas. Neste trabalho, a capacidade da equação de estado CPA para modelar a solubilidade em meio aquoso de vários PAHs numa ampla gama de temperatura, foi avaliada. Esta equação de estado combina o termo Soave-Redlich-Kwong (SRK) para descrever as interações físicas com a contribuição de associação proposta por Wertheim, também usada em outras equações de estado, tais como as diferentes versões da SAFT. A CPA EoS já foi aplicada com sucesso a sistemas aquosos com alcanos, compostos aromáticos e álcoois. Os resultados obtidos são muito próximos dos valores encontrados na literatura, sugerindo que a CPA EoS é um modelo adequado para correlacionar soluções aquosas de moléculas complexas de poluentes orgânicos. ABSTRACT: The polycyclic aromatic hydrocarbons (PAHs) are a family of compounds characterized by having two or more aromatic rings condensed. They are referenced in general because they are environmental contaminants associated with the incomplete combustion of organic materials, such as the burning of fossil fuels and incineration of waste, and oil spills. The solubility of these xenobiotics in aqueous mixtures must be monitored due to their impact on public health and the environment, because of their carcinogenic properties and their ubiquity in the environment. In this work, the ability of the Cubic-plus-Association equation of state (CPA EoS) for modelling the aqueous solubility of several PAHs in a wide temperature range was evaluated. This equation of state combines the Soave-Redlich-Kwong (SRK) EoS for describing the physical interactions with the association contribution proposed by Wertheim, also used in other associating equations of state, such as the different versions of SAFT. The CPA EoS had already been successfully applied to aqueous systems with alkanes, aromatics and alcohols. The results obtained are in very close agreement with the literature data, suggesting that the CPA EoS is an adequate model for correlating aqueous solutions of complex molecules of organic pollutants.
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Jones-Hughes, Tracey Louise. "The influence of surfactants on the sorption of phenanthrene in natural waters." Thesis, University of Plymouth, 2002. http://hdl.handle.net/10026.1/2183.
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Polycyclic aromatic hydrocarbons (PAHs) are widely recognised as harmful, persistent organic pollutants, whilst surfactants are more easily degraded but their ubiquitous use both domestically and industrially ensures their presence in natural waters. Owing to both their hydrophobic and hydrophilic properties, surfactants are capable of both adsolubilisation and solubilisation of co-contaminants, hence, their presence in natural waters is considered extremely significant. The purpose of this research was to determine how surfactants and PAHs influence each other in estuaries where both are co-disposed. This study is the first to employ environmentally realistic concentrations of surfactants and to use natural particles in order to determine how changes in surfactant behaviour impinge on the sorption of a representative PAH to sediment. The experimental method employed involved tracing the solubility and sorption of a '''C-labelled PAH (phenanthrene) in the presence of representative surfactants from the three main groups, i.e., anionic, nonionic and cationic. Initially the four compounds were examined in isolation at two temperatures (8°C and 20°C), salinities and particle concentrations. The next stage involved incorporating each surfactant with phenanthrene in the same experiment and repeating the range of variables. Solubility and adsorption of phenanthrene in the presence of Triton X-100, sodium dodecyl sulphate (SDS) or hexadecyltrimethylammonium iodide (HDTMA) proved to be highly complex. The adsorption, expressed as a Freundlich coefficient, KF was generally nonlinear and varied according to surfactant type, salinity, temperature, and contact sequence. The overriding influence, however, was sediment particulate matter (SPM) concentration. On some occasions the surfactants in isolation displayed unusual particle concentration effects (PCE), such as an increase of surfactant in the aqueous phase as the SPM concentration increased. Despite this, they all generally exaggerate the more typical PCE displayed by phenanthrene, where the particle-water partition coefficient is reduced as particle concentration increases. This effect is then modified by temperature and contact sequence, which has important environmental implications with regard to removal or release of compounds stored within sediments. However, overall, at environmentally relevant concentrations, the surfactants appear to enhance sorption, rather than solubility, with HDTMA the most effective surfactant at removing phenanthrene from the aqueous phase.
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Prodana, Marija. "Ecotoxicology of biochar-bound PAHs in runoff from amended soils." Master's thesis, Universidade de Aveiro, 2011. http://hdl.handle.net/10773/8612.
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Mestrado em Estudos Ambientais (JEMS)While the appeal of biochar application to soils continues growing, so does the concern about the possibility for surface and groundwater contamination, due to biochar-bound contaminants, such as polycyclic aromatic hydrocarbons (PAHs). Up to now, insufficient information exists on to what extent that PAH fraction can become bioavailable in the soil solution over time and which are the associated potential ecotoxicological implications, as a result of processes such as runoff. This pilot study aimed to evaluate the ecotoxicological effects of biochar-bound PAHs in runoff from soils amended with biochar, having been identified as a gap in current knowledge. Combining soil wetting-drying cycles with PAH water-extraction, a good first approach was obtained for evaluating their potential occurrence in soil solution, while taking into consideration natural soil processes and soil-biochar interactions. LUFA 2.2 soil alone and containing biochar (at usual field rates, 4% ww-1) was subjected to 0, 6 or 12 (sampling times ST-0, ST-1 or ST-2 respectively) consecutive wetting-drying cycles, after which the corresponding test elutriates were extracted. Alongside PAH quantification, a battery of standard aquatic bioassays were used with representative test organisms (Vibrio fischeri, Pseudokirchneriella subcapitata and Daphnia magna), for a robust ecotoxicological evaluation of the biochar-soil (BS) aqueous extracts, while LUFA soil elutriates were used as control (SS). Compared to the control (SS) and to elutriates of biochar alone (B), BS extracts showed the highest total PAH contents, suggesting that a relevant PAHs fraction in biochar-amended soil may be easily water-extractable, perhaps due to interactions between biochar and soil components. Yet, the number of soil wet-dry cycles on aqueous total PAH concentrations was often not significant, suggesting that natural soil wetting-drying events might have little influence on increased PAH bioavailability in pore water, on the short term. BS extracts induced toxicity in all tested species, although its extent was species-specific and varied with the number of wet-dry cycles. For example, the highest sensitivity was observed in the acute assay with D. magna exposed to BS extract for ST-0, while P. subcapitata and V. fischeri were most sensitive when exposed to BS, ST-1. Nevertheless, sub-lethal effects were also observed for P. subcapitata and V. fischeri, when exposed to the control (SS) extracts. Although the levels of individual PAHs in all samples (BS, SS and B) were below the acutely toxic concentrations reported in the literature, it cannot be excluded the combined effects of the multiple PAHs in the test elutriates when explaining these results. Furthermore, although individual PAH concentrations were below that to produce acute effects, chronic effects can occur, and therefore, long-term exposure to these elutriates and using additional non-target species, various biochars and soil properties are necessary for a full evaluation of the bioavailability and ecotoxicity of biochar-bound PAH contaminants in runoff from treated soils.
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Zhao, Zhenyong. "Biosurfactants enhanced bioremediation of PAHs contamination soil under thermophilic condition." HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/822.
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Rojas, Zarhelia Carlo. "Uptake of PAHS and metals by plants in arid environment." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Olatubi, Oluwaseun Alfred. "Metabolism of mixtures of polycyclic aromatic hydrocarbons (PAHs) by Cunninghamella elegans." Thesis, Texas A&M University, 2005. http://hdl.handle.net/1969.1/4944.
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Polycyclic aromatic hydrocarbons (PAHs) are environmentally significant compounds due to the toxicity of some members. They are ubiquitous and are persistent bioaccumulative toxins(PBTs). The toxicity of PAHs represents a risk to human health, and there are varied risk assessment approaches to quantifying the risk posed by PAHs based on exposure routes and scenarios. PAHs are not carcinogenic until they are metabolically activated as the body attempts to break them down and forms reactive metabolites that bind to the DNA causing subsequent replication in the cells. Fundamental to assessing the risk posed by PAHs is understanding the metabolism of PAHs. Since exposure to PAHs is never to single PAHs, understanding what differences may occur in mixtures of PAHs gives accurate assessment of the dangers of PAHs. Understanding the dynamics of complex metabolism vis-a-vis single metabolism of PAHs and possible effects on the toxicity expression of PAHs is a necessary advancement to accurately impact and guide remediation strategies. Studies were carried out comparing the metabolism of the PAHs Phenanthrene (PHE), Flouranthene (FLA) and Benzo[a]pyrene (BAP) in single, binary and ternary mixtures by monitoring the disappearance of the parent compound. It was observed that PAH metabolism in the single PAH experiment differed from metabolism in both binary and ternary mixtures. Enzyme competition was evident in the metabolism of mixtures, changing significantly the metabolism patterns of individual PAHs. PAH structure was also seen to affect metabolism in mixtures and the possible creation of toxicity effects during mixture metabolism. PAH concentration changed over time with faster change during single PAH metabolism followed by ternary mixture metabolism and finally binary metabolism. These results affirm that substrate interactions must be considered in the risk assessment approaches to the dangers posed by exposure to PAHs.
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Clark, III John Davis. "Body Burden of PAHs and Cardiovascular Disease in the United States." Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_dissertations/141.
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Polycyclic aromatic hydrocarbons (PAHs) are environmental and occupational carcinogens that are produced by the incomplete combustion of organic material, such as from the burning of tobacco, coal, and petroleum products. In addition to causing cancer, exposure to PAHs is hypothesized to contribute to atherosclerosis and to lead to increased incidence rates of cardiovascular disease in populations. Considering the number of deaths attributable to tobacco smoke exposure, ambient air pollution, and occupational hazards, PAHs may be a significant contributor to the prevalence of cardiovascular disease in human populations. However, a clear exposure-response relationship between PAHs and measures of cardiovascular disease has not been demonstrated. While PAH exposure has been shown to be associated with indicators of cardiovascular disease in research animals, this relationship has not been studied comprehensively in human populations. Using data from the continuous National Health and Nutrition Examination Surveys (NHANES) 1999 - 2004 of a representative sample of the entire US civilian population, this study investigated predictors of total body burden of PAHs and associations between urinary metabolites of PAHs and biomarkers of cardiovascular disease in 4,492 study participants aged 20 years and older. Using various analytic approaches, this research project identified tobacco smoke exposure as a significant predictor of urinary levels of low molecular weight PAHs but not as a predictor of urinary levels of high molecular weight PAHs in a large population of individuals without known occupational exposure to PAHs. Worker occupational category was not associated with urinary levels of any PAH metabolites. The results of this study also indicate a possible association between exposure to PAHs and the development of cardiovascular disease in humans. Levels of multiple metabolites of specific PAHs, naphthalene, fluorene, and phenanthrene were significantly associated with increases in total cholesterol, triglycerides, WBC count, and C-reactive protein levels. Additionally, this study examined the utility of factor analysis for data reduction of 23 urinary PAH metabolites to two latent factors representing low and high molecular weight PAHs to streamline investigations of the associations of PAH exposures with various health outcomes. Results of this study suggest mechanisms by which PAH exposure contributes to the burden of cardiovascular disease on human populations and the methods by which human body burden on PAHs can be measured.
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El-Sadi, Haifa. "Efficiency of PAHs removal from clayey soil using supercritical fluid extraction." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0007/MQ43546.pdf.
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Petroni, Ricardo N. (Ricardo Nicolas) 1971, and Peter H. (Peter Hampus) 1973 Israelsson. "Mass balance and 3D model of PAHs in Boston's inner harbor." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50019.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1998.Includes bibliographical references (leaves 192-199).
by Ricardo N. Petroni, Peter H. Israelsson.
M.Eng.
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MOSTEFAOUI, TOUFIK. "Nouveaux developpements experimentaux appliques a l'etude de la reactivite des pahs." Rennes 1, 2000. http://www.theses.fr/2000REN10052.
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Ce memoire presente les differentes techniques developpees pour l'etude experimentale des molecules polycycliques aromatique d'hydrocarbures (pahs). Dans la premiere partie sont exposes les appareillages utilises. Le premier appareil decrit est le falp-ms. Il permet d'etudier les reactions ion-molecule ou la recombinaison dissociative d'ions produits par une decharge micro-onde a 300 k. L'appareil cresu quant a lui permet d'atteindre des tres basses temperatures en generant un jet supersonique uniforme au travers d'une tuyere de laval. Deux nouvelles techniques sont developpees et decrites dans ce premier chapitre : la tuyere de laval chauffee et la sonde de langmuir chauffee, toutes deux developpees pour l'etude des molecules pahs. Le second chapitre est consacre a l'etude de l'attachement electronique sur l'anthracene. Pour la premiere fois une telle etude sur les pahs est effectuee aux tres basses temperatures. Ensuite, la thermalisation des electrons est etudiee et mise en evidence par la mesure de la vitesse de derive des electrons dans le jet supersonique. Cette etude est necessaire pour la validation de toutes les mesures faites deja sur l'attachement electronique aux basses temperatures. Une source d'ion a ete realisee et concue pour l'etude des reactions ou interviennent de grosses molecules du type pahs. Cette source d'ions couplee a cresu a ete utilisee pour l'etude des reactions ion-molecule aux tres basses temperatures. Cette technique est appliquee a des reaction deja etudiees qui valident notre methode. Pour la premiere fois la reaction ch + + co et etudiee aux basses temperatures. Enfin, dans le dernier chapitre sont presentes nos resultats sur la recombinaison dissociative de molecules de benzene substituees par des branches methyles. Cette etape est la premiere vers l'etude de la recombinaison dissociative des pahs.
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Wan, Cheung Kuen. "Composting as a bioremediation technology for remediation of PAHs contaminated soil." HKBU Institutional Repository, 2000. http://repository.hkbu.edu.hk/etd_ra/219.
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KODNIK, DANIJELA. "Lichens as environmental biomonitors of pollution by heavy metals and PAHs." Doctoral thesis, Università degli Studi di Trieste, 2016. http://hdl.handle.net/11368/2908052.
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I licheni, una simbiosi tra un fungo e alghe verdi e/o cianobatteri, sono privi di uno strato cuticolare e possono perciò assorbire nutrienti e contaminanti tramite deposizioni atmosferiche, sia umide che secche. Per questo motivo sono tra gli organismi più spesso utilizzati quali biomonitor di inquinamento atmosferico, in particolare di metalli pesanti. Negli ultimi anni vengono però sempre più spesso utilizzati anche come biomonitor di composti organici persistenti quali gli idrocarburi policiclici aromatici (IPA).
Il presente progetto di dottorato è finalizzato a: i) testare la validità dei licheni come biomonitor di IPA in ambienti semi-naturali mediante campionamenti del lichene autoctono Pseudevernia furfuracea (L.) Zopf. a distanza crescente dalla strada in 7 passi montani delle Dolomiti con diverse intensità di traffico; ii) verificare la presenza di eventuali pattern di distribuzione degli IPA in un ambiente ad uso del suolo altamente eterogeneo e verificare l’esistenza di differenze stagionali del contenuto degli IPA mediante trapianti di P. furfuracea in due diverse stagioni dell’anno (invernale ed estiva); iii) testare un metodo innovativo di identificazione delle fonti di inquinamento da metalli mediante misure delle proprietà magnetiche del particolato contenuto in trapianti lichenici.
Si è dimostrato che: i) i licheni possono evidenziare efficacemente l’inquinamento da IPA anche in ambienti montani con bassi livelli di contaminazione; in particolare è stato possibile osservare delle differenze significative sia tra i passi con diversa pressione di traffico, sia a diverse distanze dalla strada dello stesso passo; ii) in un ambiente altamente eterogeneo è stato possibile ricondurre pattern di distribuzione degli IPA a specifici processi produttivi, confermando che la concentrazione ambientale degli IPA è di un ordine di grandezza maggiore durante il periodo invernale rispetto a quello estivo; iii) i dati di mineralogia magnetica dei trapianti lichenici, in sostanziale accordo con quelli del loro contenuto elementare, non hanno permesso di discriminare tra le diverse fonti emittenti presenti sul territorio; è stato però possibile supportare in maniera convincente l’ipotesi che una fonte in particolare non è causa di rilasci importanti nell’ambiente.
I licheni si sono rivelati degli ottimi bioaccumulatori di IPA, sia in ambienti prossimo-naturali, sia in zone industriali e urbane. Tenere conto del periodo dell’anno durante il quale eseguire uno studio di biomonitoraggio è fondamentale per evitare il rischio di sottostime dell’inquinamento da IPA. La caratterizzazione magnetica dei campioni, affiancata alle analisi di contenuto elementare, si è rivelata una tecnica molto innovativa e promettente che potrebbe permettere di associare l’origine del particolato contenuto nei licheni ad un determinato processo produttivo, ma il suo uso in indagini ambientali necessita ancora di ulteriori approfondimenti metodologici.
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Tsai, Cheng-Nan, and 蔡政男. "Genotoxicity of PAHs and Nitro-PAHs from Incenses Burning." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/41850948682320254388.
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碩士國立成功大學
環境工程學系碩博士班
93
In this study the Ames Test, which offers reduced variability among experiments, requires smaller quantities of test chemicals and eliminate interactive systematic effects, was used to assess genotoxicity of the incense smoke. Nine different types of commercially available incenses were selected for this study. During the sampling period, three sticks were burned at the same time and the suspended particulates collected by a custom-designed sampler. Each sample filter was solvent extracted, fractionated, concentrated, and then analyzed by a GC/MS for PAHs and Nitro-PAHs. Elemental analyses on selected elements, including C, H, O, and N, were also performed for each sample. The concentrated extract from each sample was then tested with Ames Test for its genotoxicity. And the genotoxicity of PAHs and Nitro-PAHs from different incenses were measured. The results show that nitro-PAHs were not detected in any incense sample. And the composing of PAHs is alike, 3- or higher rings are major compounds. Especially, Pa, FL, Pry, CHR had the highest contributions (71.9 % ~ 50.4 %). The results of Ames test show that all incences exhibited mutagenic reaction only after adding the S9 liver homogenate. The relative genotoxicity of different incences is Hsing Shan (tw)> Hsing Shan (cn)> Lao Shan (tw)> Liao (tw)> Chen (tw)> Chen (cn)> Gui (cn)> Lao Shan (cn)> Liao (cn) as TA98, and Hsing Shan (tw)> Hsing Shan (cn)> Lao Shan (tw)> Chen (tw)> Lao Shan (cn)> Chen (cn)> Liao (tw)> Liao (cn)> Gui (cn) as TA100. For incenses of similar raw materials, Taiwanese incense had higher toxicity then the corresponding Chinese incense. Major factors affecting toxicity among different incenses include carbon content and combustion duration. It is imortant to note that incenses with higher carbon content generate smoke with higher genotoxicity.
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Chuang, Kung-Shun, and 莊恭旭. "Treatment of PAHs in Wastewater Using Surfactant and PAHs Degradation Bacteria." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/64897007703875902150.
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碩士國立中山大學
海洋環境及工程學系研究所
88
In this research，we used three kinds of surfactant ，including Triton X-100(nonionic surfactant)，Triton QS-15 and SDS(anionic surfactant) ，to study the effects of PAHs degradation bacteria on phenanthrene. In addition， we also discussed the treatment effects of salicylate， which was functioned as an inducer，on degradation of phenanthrene by the microorganisms with and without the three surfactants. According to the experimental results，the conclusions were as following： 1. Biodegradation of PAHs was interfered by species surfactant，which was affected by the experimental factor，species of surfactant and bacteria. 2. In the low level of Triton X-100 system ，salicylate could enhance the degradation of phenanthrene. 3. The effect of degrading phenanthrene was obvious by adding salicylate to the system. 4. In the system containing Aluminum oxide and Triton QS-15， it could not enhance the degradation effects on phenanthrene. In the future study， we suggest to further discuss the enhancing effects of surfactant on bioremediation of PAHs.
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Chuang, Ying-Yung, and 莊英湧. "Investigation of polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs in the fishing harbors." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/7fpm29.
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碩士崑山科技大學
環境工程研究所
102
In recent years, because of technological civilization progress of human. In energy use, the gradual shift from coal to oil or gas..... etc., and quite frequent usage of petroleum products. Petroleum products in the refining process at different temperatures, the result of incomplete combustion pollutants generated environment polycyclic aromatic hydrocarbons (PAHs) and its alkyl derivatives of polycyclic aromatic hydrocarbons (Alkyl-PAHs). This study is an important port of Hualien in eastern Taiwan and success fishing harbor sampling and analysis, as people improve the quality of life of leisure, and Hualien Harbor and success fishing harbor from a traditional fishing village into a leisure complex casual fishing port, the harbor is relatively vessels in the region are more diverse. When people are fishing on the oceans, transportation, recreation and other activities, resulting in the ship shipping caused by marine oil spills, emissions…etc, pollution, ecological risk of contamination of the entire ocean is relatively upgrade. Which polycyclic aromatic hydrocarbons, polycyclic Aromatic Hydrocarbons in oil pollutants, in this study, summer and winter of 102 years, and 03 years of winter for fishing port of Hualien harbor and successfully sampled, Using the 16 PAHs and alkylated-PAHs data released by US Environmental Protection Agency (US EPA) as the target pollutants for the contaminated areas, and according to the Taiwan Environmental Analysis Laboratory NIEA S104.31B sediment sampling methods and EPA 8270 method via gas chromatograph mass spectrometry (GC-MS) analysis, and to analyzes and categorizes of PAHs partly in low molecular weight (2, 3 rings) of PAHs、high molecular (4~6 rings) of PAHs、total concentration of PAHs and the percentage concentration of each ring PAHs；And investigate Alkylated-PAHs of PAHs 2 ring Naphthalene, using chemical fingerprint and characteristic -ratio analyzing method of Hualien Harbor and success possible sources, we find that Hualien Harbor sediments the possible sources of petroleum and combustion; successfully Harbor sediments the possible sources of combustion.
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Zhang, Zhi Cheng, and 張志誠. "PAHs分解菌之分離及其對PAHs之分解." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/45318233874654878423.
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Chen, Fei-Liang, and 陳飛良. "Wet Deposition of Atmospheric PAHs." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/44161419391551075790.
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碩士國立屏東科技大學
環境工程與科學系
88
Wet and dry deposition are two major transport pathways of polycyclic aromatic hydrocarbons(PAHs) to terrestrial and aquatic ecosystems. Based on the remoral efficiency, wet deposition is the more significant process than dry deposition. In this study, wet deposition and air sampling will be investigated in the ambient air of a PCI(petrochemistry industry ) plant and a rural site with automated wet-only collectors and PS-1 samplers. A wet-only collector will be developed to collect large volumes of precipitation and to isolate the particle-associated and dissolved fractions of PAHs during each precipitation event. During periods of no rain or threat of rain, gaseous and particle-bound PAHs will be sampled from the ambient air by using PS-1 samplers. The results of this investigation are as follows: The concentrations of PAHs in the atmosphere of industrial area were higher than those in rural site. So, the concentrations of PAHs that can be scavenged in the rain were relative high. For both PCI and rural sites, the concentrations of particle-bound PAHs in the rain samples were higher than those of dissolved. This is because that the scavenging of particle-bound concentrations of PAHs is more efficient than the scavenging of dissolved concentrations of PAHs in wet deposition. The phenomenon that PAHs deposition flux increase with increasing rainfall intensity implies the significance of below-cloud scavenging because below-cloud scavenging only occurs during precipitation events. Accordingly the presence of PAHs in rain is probably mainly the result of below-cloud scavenging instead of in-cloud scavenging. The efficiencies of particle (Wp) and gas (Wg) washout were higher in rural than those in PCI site. For both PCI and rural sites, the efficiencies of particle washout were higher than those of gas washout in wet deposition of PAHs. For 21 individual PAHs in the rain samples, the high-molecule-weight PAHs, such as COR, BkF and BbC at the rural while COR, BeP and PER at the PCI, had higher gas washout efficiencies. Except COR, the lower-molecule-weight PAHs, such as Nap, BbC, AcPy and Flu at the rural while Nap, Acp, Flu and PA at the PCI, had higher particle washout efficiencies. The average TC concentration of the particles in precipitation was 186.6 and 462.8 ng/L for the rural and industrial area, respectively. The average EC concentration of the particles was 120.6 and 209.5 ng/L for the rural and industrial area. The average OC concentration in the particle was 65.7 and 235.25 ng/L for the rural and industrial area. The TC , EC and OC concentration in industrial area were 2.48, 1.74 and 3.85 times higher than those in rural area. The average OC/TC and OC/EC ratio were 0.35 and 0.54 for the industrial area, while the average OC/TC and OC/EC ratio are 0.55 and 1.21 for the rural area, respectively. The OC/TC(1:1.57) and OC/EC (1:2.24) ratio for the rural area were less than those for the industrial area. The PAH was related to TC for both of the industrial and rural area. While the PAH was related to EC only in the rural area and was related to EC only in the industrial area. The information about the wet deposition of PAHs is scattered in the field investigation. The results of this study are important to develop the strategies for controlling of PAHs and understanding the processes that transport and scavenge PAHs from the atmosphere. But it is necessary to get reliable correlativity between the concentrations of PAHs and the concentrations of the relative matter in the rain by more experiment.
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Su, Ching Mao, and 蘇靖貿. "Characteristics of PAHs Affected by Seasonal Variation." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/55922488093116887255.
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碩士國立雲林科技大學
環境與安全工程系碩士班
89
Seasonal variation affected both the particle size composition and the adsorption of particles on polycyclic aromatic hydrocarbons (PAHs) in atmospheres. The study was chosen summer and winter seasons in the southern part of Taiwan to represent substantial variation of particle concentration in regions. Several samplers with similar flow rate were simultaneously conducted to collect the mass concentration of various particles, and also to measure the gas and particle concentrations on fifteen PAHs at traffic circumstance in urban areas. We tried to investigate the seasonal differences of concentration and composition ratios in particle size distributions、gas / particle phase partitioning and particulate fraction (ψ) on semi-volatile PAHs components. Results were shown that mass concentration of particles was almost 50% more in winter season. But, the composition ratios from different size particles (included PM<2.5, PM2.5-10, and PM>10) were similar in both seasons. From the view of PAHs concentrations ( ng m-3 ), the summer / winter ratios of PAHs among PM<2.5, PM2.5-10, and PM>10 were 0.65, 0.82, 0.62. The PM<2.5 particle has the highest value of PAHs concentrations in winter and summer seasons. Those experimental data were verified by the correlation of the volatility with gas/particle partitioning coefficient (Kp) on 3-4 rings of PAHs components. Applying the sub-cooled vapor pressure (PL) of PAHs rather than solid vapor pressure (Ps) would contribute a good correlation (r2=0.97) to prove the evidence of adsorptive characteristics in atmospheric particles. The non-exchangeable factors (X, %) in various particles have shown a promising correlation with PL parameter. Because of low humidity causing the less water competition at adsorptive site in particles, data from winter season offered a good correlation between the non-exchangeable factors and PL vapor pressure of PAHs. The Jungle-Pankow model gives particulate fraction (ψ) for 3-ring PAHs (AcPy、AcP) which was underestimated. Filtration air samplers are subject to “blow-off” artifacts, which result in loss of semivolatile compounds from filtered particles. The gas/particle distribution of PAH is underpredicted, this may be related to the presence of sampling non-exchangeable PAHs or due to the long times required for aerosol-air reequilibration.
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Yan-Laing, Chen, and 陳彥良. "Biodegradation of Five PAHs in River Sediment." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/93212937441529371009.
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碩士東吳大學
微生物學系
87
Abstract In order to assess the possible bioremediation for polynuclear aromatic hydrocarbons (PAHs) contaminated sediments, acenaphthene, fluorene, phenanthrene, anthracene and fluoranthene were spiked to sediments collected from monitoring sites of middle and down stream of Ke-Lung River which located in northern part of Taiwan. The collected sediments consortia were acclimatized in laboratory with phenanthrene for 6 months before testing. The results showed the optimal conditions for PAHs biodegradation using K8 sediment were 35-40 oC and higher acidic or alkali pH under aerobic incubation. For K12 sediment(estuarine sediment), 30-40 oC and pH 7.0-9.0 were found. The rates(K) of PAHs biodegradation in K8 sediments (freshwater sediment) were observed as anthracene(0.586 day-1) > fluoranthene (0.349 day-1) > acenaphthene(0.374 day-1) > phenanthrene (0.148 day-1) > fluorene(0.014 day-1). For K12 sediment, rates(K) of PAHs showed as anthracene (0.593 day-1) > fluoranthene (0.549 day-1) > phenanthrene (0.549 day-1) > fluorene (0.409 day-1) > acenaphthene (0.109 day-1). Acetate, lactate, pyruvate or yeast extract added to incubation vials as carbon source could enhance acenaphthene and phenanthrene biodegradation, but the other PAHs were reduced. Adding nitrate as nitrogen source also enhance PAHs biodegradation for K8 sediment. However, for K12 sediment, only acenaphthene and fluoranthene showed increase biodegradation rate. The result also indicated that PAHs biodegradation rate in the control vial (liquid medium without sediment) was increased. For anaerobic incubation, after six months acclimation K8 sediment showed much higher biodegradation rate when unacclimatized same sediment were compared. Both for K8 and K12 sediment under different pH control showed biodegradation rate in the order of alkali > acidic > neutral. The optimal temperature for biodegradation is 35 oC. The rates(K) of PAHs anaerobic biodegradation in K8 sediments were observed as anthracene (0.0743 day-1) > acenaphthene (0.0646 day-1) > fluoranthene (0.0471 day-1) > phenanthrene (0.0266 day-1) > fluorene (0.0022 day-1). However no significant difference were found for K12 sediment. The rates(K) were at range of 0.10-0.060 day-1. Comparison influence of PAHs concentration (0.5-10mg/L) on biodegradation under simulated denitrifying, sulfodogenic or methanogenic conditions, for 0.5-2 mg/L PAHs in incubation vials, K8 or K12 sediment showed higher biodegradation rate. The addition of electron donors acetate, lactate, pyruvate, or electron acceptors manganese oxide or ferric chloride to incubation vials, all enhance PAHs biodegradation. In conclusion, K12 sediment showed higher biodegradation capacity than K8 sediment for all 5 PAHs under aerobic or anaerobic conditions in laboratory studies. All results could be used for further application of bioremediation for clean-up of PAH-contaminated sediments.
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Liow, Ming-Chu, and 廖明珠. "PAHs Emission from the Medical Waste Incinerator." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/91036203735955977640.
Full textAbstract:
碩士國立成功大學
環境工程與科學系
85
A batch-type medical waste incinerator with one mechanical grate and on fixed grate was used to incinerate the infectious waste and pathological waste, respectively. The concentration and composition of 21 individual PAHs (polycyclic aromatic hydrocarbons) in the stack flue gas, the fly ash from ESP(electrostatic percipitator), the effluent from wet scrubber and the bottom ash were investigated. The stack flue gas samples were collected isokinetically by a PAH sampling system, while twenty one individual PAHs were primarily analyzed by the GC/MS. The distribution of PAHs emissions from mechanical grate and fixed grate were similar. The stack gas was found to have the majority of total PAHs emission (93%), while the distribution of total PAH mass discharged from the wet scrubber, the fly ash from ESP and the bottom ash were only 4.8%, 1.8% and 0.24%, respectively. The mean total- PAHs concentrations were 1290ug/Nm3 and 635ug/NM3 in the stack flue gas of mechanical grate and fixed grate, respectively. The majority (95%) of total PAHs concentration was contributed by the two and three rings PAHs(Nap, AcPy, Acp, Flu, PA and Ant). Among these 21 individual PAHs, Nap had the highest mean concentration. PAh mass distribution collected by the PAH sampling system were 96%, 2.9%, 0.28% and 0.38% for the gas phase, particle phase, water from cooling device and residual in the pipe, respectively. The removal efficiency of ESP for higher molecular weihgt PAHs (BaA, CHR, BbF, BaP RF, PER, IND, BbC and BghiP) averaged 26%, and that for low molecular weight PAHs (NaP, AcPy, Acp, Flu, PA and Ant) were below 5%.
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Borges, Bárbara Alexandra Guimarães. "Aplicação da Técnica de Microextração Dispersiva Líquido-Líquido na Avaliação da Contaminação da Água por PAHs e Nitro-PAHs." Master's thesis, 2015. https://repositorio-aberto.up.pt/handle/10216/80190.
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Borges, Bárbara Alexandra Guimarães. "Aplicação da Técnica de Microextração Dispersiva Líquido-Líquido na Avaliação da Contaminação da Água por PAHs e Nitro-PAHs." Dissertação, 2015. https://repositorio-aberto.up.pt/handle/10216/80190.
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Hsieh, Yun-chu, and 謝雲竹. "Phytoremediation of PAHs(pyrene) Contaminated Soils through mangroves." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/q2ep2f.
Full textAbstract:
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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HuangChi-Nan and 黃啟南. "Transportation and Remediation of PAHs in Different Soils." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/36276157028030654884.
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碩士崑山科技大學
環境工程研究所
94
The focus of this research is on the transportation of PAHs in different soils. Three nonionic surfactants such as natural organic matter (NOM)﹐Tween 80﹐Triton X-100﹐will be separately and sequentially used to investigate the remediation efficiencies of PAHs contaminated soils. Experiments are devided into two parts﹐including the static column experiments﹐and the continuous-flow column experiments which is design to simulate the contaminant transportation in real groundwater. The flushing solutions of surfactants were performed under the condition of fixed temperature and flow rate. The relationships between solid phases and different solutes will be investigated thoroughly to find the best remediation condition to be used in contaminated sites. When humic acid was used as the desorbing solution, there is no great difference compared to that of sodium nitrate to desorbed naphthalene from soils﹐but have obvious result in desorbing anthracene (desorb rate＞21％). If the two nonionic surfactants were used as desorbing solution﹐it showed more than 55% of removing efficiencies of anthracene and naphthalene in both Yu-long soil or Kun-shan soil. Since the concentrations of anthracene and naphthalene in the soils were low, the increases of the solubilities were limited. When the desorption experiments were done using the contaminated soils of 500 mg/g of PAHs, the apparent solubility can increase up to 30 times, Column experiments were adopted to understand the availability of using nonionic surfactants to remediation real site PAHs contaminated soil. For anthracene which has a higher hydrophobicity than naphthalene showed higher desorption efficiency than that of using only groundwater or humic acid solution. We also found that the surfactants caused the mobility of colloids from the particles, and resulted the clog of column. In the research, the optimal concentrations of Tween 80 and Triton X-100 are 0.1%, it can have good removing efficiencies for PAHs contaminated soils and will not resulte the clogging of soil column. The movement of colloids should be noticed in the application of surfactants to field remediation.
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Shieh, Wen-Bin, and 謝文賓. "Biodegradation of Polycyclic Aromatic Hydrocarbons(PAHs) in soil." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/92661547888525455295.
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Chu, Chi-Hung, and 朱啓宏. "Accumulation and distribution of PAHs in marine plankton." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/496y2v.
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碩士國立東華大學
海洋生物多樣性及演化研究所
102
As the lower trophic levels, plankton afford sufficient basic product to maintain the food web, especially phytoplankton not only play a primary producer but also a carrier of persist organic pollutions (POPs) from seawater into biota. The study simulated the field of plankton food chain to understand the accumulation and distribution of polycyclic aromatic hydrocarbons (PAHs) in phytoplankton and zooplankton at different points of exposure time. The plankton food chain constructed by phytoplankton (Tetraselmis chuii), rotifers (Brachionus sp.), and copepods (Apocyclops sp.), which cultured in a steady supply of PAHs gas purging system during 168 hours. The results show that PAHs accumulation in plankton could roughly divide into three sections: 0.2-1 hours, 1-24 hours, and 24-168 hours. The PAH concentrations in plankton variance at 0.2-1 hours and 1-24 hours, then approached study-state at 24-168 hours exposure. The low molecular weight PAHs (ACN, AC) in copepod were significantly higher than in rotifer and phytoplankton, but the high molecular weight PAHs (FA and PY) were significantly higher in phytoplankton, indicating that the plankton might have selectivity to PAHs. In principal component analysis (PCA), phytoplankton and zooplankton could significantly separated to two groups, among the PAHs accumulative part of rotifer and copepod were similar, demonstrating the PAH composition in plankton might be effected by trophic levels. In the relationship between bioconcentration factor (BCF) and PAHs hydrophobicity (Kow) in part of phytoplankton, rotifer and copepod, all of them show a great linear relationship. Compare the linear regression slopes of log BCF and log Kow between phytoplankton, rotifer and copepod, the significantly different results suggested that the cumulative pathway of PAHs were different in plankton. According to the biomagnification factor (BMF) to estimate PAHs accumulation through feeding, the low molecular weight PAHs (ACN, AC) might have risk of biomagnifications in plankton than high molecular weight PAHs.
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Long-Lai, Teh, and 賴特隆. "Study of MIcrowave-Assisted Extraction PAHs from soils." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/67146124856192744781.
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Yang, Cheng-Ta, and 楊承達. "Internal Exposure to PAHs of Motorcycle Maintenance Workers." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/57997998211482124387.
Full textAbstract:
碩士國立聯合大學
環境與安全衛生工程學系碩士班
103
Polycyclic Aromatic Hydrocarbons (PAHs) is identified as a carcinogen and can be released into our ambient environment by vehicle powered by petroleum fuel. Occupational exposure to PAHs owing to traffic emissions have been reported including street vendors, traffic policemen, gas station workers and outdoor workers etc. These people, those working in industries, were exposed to PAHs. The health risk due to exposure to PAHs may thus need to be justified. Oxidative stress is a potential indicator of DNA damage and therefore might provide information of cancer incidence. This study invited ten workers who were identified to be exposed to PAHs. They provided their start-of-shift and end-of-shift urine samples for consecutive five days. The levels of urinary 8-OHdG and1-OHP were analyzed to estimate the potential oxidative stress and PAHs exposure. The average total concentration of PAHs was 3516.64 ng/m3 for exposure group and 397.30 ng/m3 for control group. The concentration of 1-OHP was 4.49 μg/g creatinine for exposure group and 0.20 ng/g creatinine for control group. There was significant difference between start-of-shift and end-of-shift values of motorcycle maintenance workers. The study showed that motorcycle maintenance workers concentration of 1-OHP was higher than some occupation like street vendors, traffic policemen etc .
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Hsing-Hua, Wei, and 魏興華. "Degradation of polycyclic aromatic hydrocarbons(PAHs) in soil." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/70353808925773836361.
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Chen, Tse-An, and 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.