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Data publikacji: 4 czerwca 2021

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Harrad, Stuart J. "Levels and sources of PCDDs and PCDFs in UK soils". Thesis, University of East Anglia, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327955.

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Hess, Philipp. "The determination and environmental significance of planar aromatic compounds in the marine environment". Thesis, Robert Gordon University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388494.

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Gaus, Caroline, i n/a. "Dioxins in the Marine Environment: Sources, Pathways and Fate of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans in Queensland, Australia". Griffith University. School of Public Health, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030624.144111.

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Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans(PCDFs) are two groups of lipophilic, persistent organic pollutants that are produced as by-products of various anthropogenic and industrial processes. Due to their relatively high toxic potencies and potential to bioaccumulate and biomagnify in organisms and through the food chain, the contemporary widespread distribution of these compounds is a concern to the health of the environment, wildlife and humans. This study determined the distribution, pathways and fate of PCDD/Fs in the coastal zone of Queensland, Australia, including the inshore marine environment of the World Heritage Great Barrier Reef Marine Park. This ecosystem supports unique fauna and flora such as the marine herbivorous mammal dugong (Dugong dugon) and its food source, seagrass. Elevated PCDD/Fs were present in soils and sediments along the entire Queensland coastline. Highest concentrations were found in soil from agricultural irrigation drains and in sediments near the mouths of major rivers. Elevated concentrations were associated with rural and urban types of land-use, and PCDD/Fs were present even in locations remote from anthropogenic activities. PCDD/F congener-specific analysis revealed an unusual profile in all samples, dominated by OCDD, with PCDFs present in low concentrations or below the limit of detection. Distinct HxCDD isomer patterns were observed, with the 1,2,3,7,8,9-HxCDD/1,2,3,4,6,7-HxCDD isomer pair dominating the 2,3,7,8-substituted HxCDDs. Similar congener and isomer characteristics were reported in sediments, soil and clay samples from other continents, but could not be attributed to any known source. Possible PCDD/F sources in Queensland were assessed using segmented estuarine sediment cores, for which radiochemical chronologies were established for each depth. Variations of PCDD/F concentrations in the sediment cores over several centuries of depositional history were relatively small. Elevated PCDD levels were still present in sediment slices from the early 17th century. PCDD/F homologue profiles in sediments deposited during the last 350 years were almost identical and correlated well to the characteristic profiles observed in surface sediments and soils from the entire Queensland coastline. These results suggested the presence of an unidentified PCDD source prior to the production of commercial organochlorine products. To investigate the formation of the unusual PCDD/F profiles, congener and isomer specific analyses were undertaken in soils, sediments and dated sediment cores. The results demonstrated that specific transformation processes in the environment have resulted in the observed PCDD profile characteristics. Dechlorination of OCDD was proposed to result in distinct 1,4-pattern characteristics (i.e. formation of isomers chlorinated in the 1,4,6,9-positions). Consequently, the environmental samples do not reflect the signatures of the original source. An alternative hypothesis to natural formation is discussed evaluating these processes and their implications for possible source contributions. This hypothesis explores the potential for the influence of anthropogenic PCDD precursors (e.g. pentachlorophenol) during the 1940s to 1990s. Transport of PCDD/Fs from the land-based source via impacted tributary river systems, and subsequent deposition processes are proposed to result in PCDD/F accumulation in the inshore marine ecosystem. The extent of the sediment PCDD/F contamination governs the concentrations in the extensive inshore marine seagrass meadows of Queensland. Partitioning processes in the sediment-seagrass system lead to increased toxic equivalency (TEQ) in the seagrass, compared to sediment.The relationship between contaminated inshore sediments, seagrass and dugongs were evaluated using six dugong habitat regions along the coastline. PCDD/F body burdens in dugongs are governed by sediment (and seagrass) PCDD/F concentrations in their habitat. High seagrass (and incidental sediment) ingestion rates, selective retention of toxicologically potent congeners and relatively low PCDD/F elimination capacities in dugongs are proposed to result in elevated PCDD/F concentrations and TEQ levels in adult animals. Transfer efficiencies of 4 and 27% of maternal TEQ levels to foetuses and calves (respectively) during gestation and lactation result in relatively high exposure potentials to offspring. Compared to no-observed-adverse-effect-levels in other mammals, and based on the results of this study, a tolerable daily intake (TDI) of 10-24 pg TEQ kg-1 day-1 was estimated for dugongs. The results of the present study found that dugongs from some regions along the coastline of Queensland exceed this TDI by up to 20 fold, suggesting that these populations may be at risk from PCDD/F contamination in their habitat. These results have important implications for the health of the environment, wildlife and humans and were used to develop a conceptual understanding of the sources, pathways and fate of dioxins in Queensland, Australia.

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Gaus, Caroline. "Dioxins in the Marine Environment: Sources, Pathways and Fate of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans in Queensland, Australia". Thesis, Griffith University, 2003. http://hdl.handle.net/10072/367537.

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Mohr, Susana. "RESÍDUOS DE POLUENTES ORGÂNICOS PERSISTENTES EM MEL DE ABELHAS: REPERCUSSÕES DA CONTAMINAÇÃO AMBIENTAL". Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/3407.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Persistent Organic Pollutants (POPs) are chemical substances that are widely distributed throughout the environment, accumulate in the fatty tissue of living organisms, are found at higher concentrations in the food chain and are toxic to both humans and wildlife. In the present work, POPs were determined in honey samples from different geographic regions, evaluating both the quality and safety of honey as food, and the environmental contamination of the studied regions. Organochlorine pesticides were analysed in 186 samples from the South region of Brazil, with concentrations between Os Poluentes Orgânicos Persistentes (POPs) são compostos químicos sintéticos que estão amplamente distribuídos no meio ambiente, acumulam-se nos tecidos lipídicos dos seres vivos, são encontrados em altas concentrações na cadeia alimentar e apresentam efeitos tóxicos aos seres humanos e animais. No presente trabalho, os POPs foram determinados em mel de abelhas de diferentes regiões geográficas, buscando avaliar a qualidade e segurança do mel como alimento, bem como a contaminação ambiental das regiões estudadas. Os praguicidas organoclorados foram analisados em 186 amostras da região Sul do Brasil, com concentrações que variaram entre

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Larsson, Daniel. "Mobilisation of soil-bound dioxins at an old sawmill area : Impact of excavation on groundwater levels of PCDF/PCDDs at Norrbyskär". Thesis, Umeå universitet, Kemiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-124420.

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Danielsson, Conny. "Trace analysis of dioxins and dioxin-like PCBs using comprehensive two-dimensional gas chromatography with electron capture detection". Doctoral thesis, Umeå universitet, Kemiska institutionen, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-963.

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Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), two groups of struc-turally related chlorinated aromatic hydrocarbons, generally referred to as “dioxins” are of great concern due to their extreme toxicity and presence in all compartments of the environment. Since they occur at very low levels, their analysis is complex and challenging, and there is a need for cost-efficient, reliable and rapid analytical alternatives to the expensive methods in-volving use of gas chromatography high-resolution mass spectrometry (GC-HRMS). It is im-portant to routinely monitor food and feed items to detect contaminations at an early stage. For the regulation of dioxins and dioxin-like PCBs in food and feed according to current legis-lation, large numbers of samples have to be analysed. Furthermore, soils at many industrial sites are also contaminated with dioxins and need remediation. In order to optimize the cost-efficiency of reclamation activities it is important to acquire information about the levels and distribution of dioxins in the contaminated areas. The aim of the studies underlying this thesis was to investigate the potential of comprehen-sive two-dimensional gas chromatography with a micro-electron capture detector (GC × GC-µECD) as a cost-effective method for analysing dioxins and dioxin-like PCBs in food, feed, fly ash and contaminated soils. Quantification studies of dioxins and dioxin-like PCBs were con-ducted and results were compared with GC-HRMS reference data. Generally, there was good agreement between both the congener-specific results and data expressed as total toxic equiva-lents (TEQs). The developed GC × GC-µECD method meets the European Community (EC) requirements for screening methods for control of dioxins and dioxin-like PCBs in food and feed. The presented results also indicate that GC × GC-µECD has potential to be used as a routine method for the congener-specific analysis of 2,3,7,8-PCDD/Fs and dioxin-like PCBs in matrices such as food and feed, fly ash and soil. However, to fully exploit the potential of the GC × GC-µECD technique, it should be combined with a fast and cost-efficient sample preparation procedure. Therefore, a number of certified reference materials (CRMs) were extracted using a new shape-selective pressurized liquid extraction technique with integrated carbon fractionation (PLE-C), and the purified extracts were analysed for PCDD/Fs using GC × GC-µECD. The results compared well with the certified values of a fly ash and a sandy soil CRM, but they were much too high for a com-plex clay soil CRM. It was concluded that this combination of techniques was very promising for screening ash and highly permeable soils. Further assessments and method revisions are still required before GC × GC-µECD can be used on a routine basis, and available software packages need to be refined in order to accelerate the data-handling procedures, which currently restrict the sample throughput.

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Xu, Weiguang. "Risk assessment of dietary exposure to PCDD/PCDFs, DL-PCBs and NDL-PCBs of Hong Kong residents". HKBU Institutional Repository, 2012. https://repository.hkbu.edu.hk/etd_ra/1407.

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Prange, Joelle, i n/a. "Origin of Dioxins in Queensland: Investigations into the Distribution and Sources of Polychlorinated Dibenzo-P-Dioxins in the Queensland Terrestrial Environment". Griffith University. School of Public Health, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040615.161651.

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Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) are persistent organic pollutants of global concern as they are persistent, toxic and can biomagnify through the food chain. PCDD/Fs are generally regarded as trace contaminants in a number of chemical products and they are formed as by-products from various industrial, chemical and combustion processes. The pollution with PCDD/Fs occurs with the release of these chemicals into the environment, resulting in the contamination of various compartments including; air, soil, sediment and biota. Studies that have investigated the distribution of PCDD/Fs in the environment suggest that the highest concentrations of these pollutants are found in locations with a history of industrial or chemical PCDD/F sources. Queensland is the north-eastern state of Australia. Queensland has a low population density, few industrial activities and is considered predominantly rural. Therefore it was somewhat surprising that elevated concentrations of PCDD/Fs (in particular the higher chlorinated PCDDs) have been observed in soil and sediments samples collected from various locations along the Queensland coast. The concentrations of PCDDs in Queensland samples were comparable to or higher than concentrations in similar matrices from highly polluted regions elsewhere. To investigate the origin of PCDDs in Queensland, the geographical distribution of PCDD/Fs in topsoil was investigated in the coastal and inland environments to provide information on the potential sources and to estimate the extent of the PCDD contamination. Distinct east-west gradients were detected in topsoil collected from bushland areas across the state with elevated PCDD concentrations confined to the coastal region. Within the coastal region, the contamination could not be associated with specific land uses. In fact, the PCDD/F congener profile was similar in the majority of samples from the coastal region, with a dominance of the higher chlorinated PCDDs (in particular OCDD), whereas PCDFs were low or below the limit of detection. The similarity in the PCDD/F congener profiles in the soils along the coastal region indicated that a source of PCDDs of similar origin has resulted in the contamination of soil extending more than 3000 km and estimations suggest that more than 50 tonnes of OCDD is stored in the topsoil of Queensland.s coastal region. Investigation into the vertical distribution of PCDDs in Queensland coastal soils revealed elevated concentrations of PCDDs, (in particular OCDD) in soils to at least 3.5 m. These results indicated that the extent of the PCDD contamination is significantly greater than anticipated and it was estimated that there is in the order of 3 000 tonnes of OCDD stored in Queensland's coastal soils. The specific PCDD/F congener profile in Queensland coastal soils is unlike known PCDD/F source profiles which led to the suggestion that some yet unidentified formation mechanism may have resulted in the contamination. Potential natural sources of PCDD/Fs, including forest fires, geogenic and biogenic processes were assessed as possible origins for the PCDD contamination in Queensland. Elevated concentrations of PCDDs were detected in the atmosphere during a 'prescribed burn'. This study demonstrated that although forest fires influence atmospheric PCDD/F concentrations substantially, forest fires are not the source of PCDDs in Queensland; rather they are an important mechanism for the redistribution of PCDDs and may have attributed to the widespread PCDD contamination. In this study geological materials (oil shale and kaolin) were analysed as a proxy to assess a geogenic origin of PCDDs. Elevated concentrations of PCDDs were observed in the kaolin samples, however similar and higher concentrations were detected in surface and sub-surface soils, suggesting that specific geogenic formation processes investigated are not the source of PCDDs in Queensland. A preliminary indication for a biogenic origin of PCDDs was identified during the anaerobic incubation of sugarcane irrigation sediments. An increase in the concentration of OCDD in the anaerobic treatment, compared to the control was observed after incubation for 90 days. In these same experiments, a dechlorination of OCDD to lower chlorinated (1,4,6,9-substituted) PCDDs was also observed. Similar transformation processes were observed in other anaerobic environments in Queensland, which led to the suggestion that a biogenic formation of PCDDs (possibly from a precursor) may be responsible for the origin of PCDDs in Queensland.

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Prange, Joelle. "Origin of Dioxins in Queensland: Investigations into the Distribution and Sources of Polychlorinated Dibenzo-P-Dioxins in the Queensland Terrestrial Environment". Thesis, Griffith University, 2004. http://hdl.handle.net/10072/367289.

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Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) are persistent organic pollutants of global concern as they are persistent, toxic and can biomagnify through the food chain. PCDD/Fs are generally regarded as trace contaminants in a number of chemical products and they are formed as by-products from various industrial, chemical and combustion processes. The pollution with PCDD/Fs occurs with the release of these chemicals into the environment, resulting in the contamination of various compartments including; air, soil, sediment and biota. Studies that have investigated the distribution of PCDD/Fs in the environment suggest that the highest concentrations of these pollutants are found in locations with a history of industrial or chemical PCDD/F sources. Queensland is the north-eastern state of Australia. Queensland has a low population density, few industrial activities and is considered predominantly rural. Therefore it was somewhat surprising that elevated concentrations of PCDD/Fs (in particular the higher chlorinated PCDDs) have been observed in soil and sediments samples collected from various locations along the Queensland coast. The concentrations of PCDDs in Queensland samples were comparable to or higher than concentrations in similar matrices from highly polluted regions elsewhere. To investigate the origin of PCDDs in Queensland, the geographical distribution of PCDD/Fs in topsoil was investigated in the coastal and inland environments to provide information on the potential sources and to estimate the extent of the PCDD contamination. Distinct east-west gradients were detected in topsoil collected from bushland areas across the state with elevated PCDD concentrations confined to the coastal region. Within the coastal region, the contamination could not be associated with specific land uses. In fact, the PCDD/F congener profile was similar in the majority of samples from the coastal region, with a dominance of the higher chlorinated PCDDs (in particular OCDD), whereas PCDFs were low or below the limit of detection. The similarity in the PCDD/F congener profiles in the soils along the coastal region indicated that a source of PCDDs of similar origin has resulted in the contamination of soil extending more than 3000 km and estimations suggest that more than 50 tonnes of OCDD is stored in the topsoil of Queensland.s coastal region. Investigation into the vertical distribution of PCDDs in Queensland coastal soils revealed elevated concentrations of PCDDs, (in particular OCDD) in soils to at least 3.5 m. These results indicated that the extent of the PCDD contamination is significantly greater than anticipated and it was estimated that there is in the order of 3 000 tonnes of OCDD stored in Queensland.s coastal soils. The specific PCDD/F congener profile in Queensland coastal soils is unlike known PCDD/F source profiles which led to the suggestion that some yet unidentified formation mechanism may have resulted in the contamination. Potential natural sources of PCDD/Fs, including forest fires, geogenic and biogenic processes were assessed as possible origins for the PCDD contamination in Queensland. Elevated concentrations of PCDDs were detected in the atmosphere during a 'prescribed burn'. This study demonstrated that although forest fires influence atmospheric PCDD/F concentrations substantially, forest fires are not the source of PCDDs in Queensland; rather they are an important mechanism for the redistribution of PCDDs and may have attributed to the widespread PCDD contamination. In this study geological materials (oil shale and kaolin) were analysed as a proxy to assess a geogenic origin of PCDDs. Elevated concentrations of PCDDs were observed in the kaolin samples, however similar and higher concentrations were detected in surface and sub-surface soils, suggesting that specific geogenic formation processes investigated are not the source of PCDDs in Queensland. A preliminary indication for a biogenic origin of PCDDs was identified during the anaerobic incubation of sugarcane irrigation sediments. An increase in the concentration of OCDD in the anaerobic treatment, compared to the control was observed after incubation for 90 days. In these same experiments, a dechlorination of OCDD to lower chlorinated (1,4,6,9-substituted) PCDDs was also observed. Similar transformation processes were observed in other anaerobic environments in Queensland, which led to the suggestion that a biogenic formation of PCDDs (possibly from a precursor) may be responsible for the origin of PCDDs in Queensland.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Public Health
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Yang, Yun. "Temperature dependent PCDD/PCDF product distributions from phenols". Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/20182.

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Frýba, Lukáš. "Analýza alternativ odstraňování PCDD/F při spalování odpadů". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229471.

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The thesis is focused on analyzing the current status of the technology used for cleaning flue gas from persistent organic pollutants, especially PCDD/F. For the three most commonly used methods of solution operational and energy efficiency comparison was made, where achievable energy export and the impact of the change in working conditions on the efficiency indicators of energy production and use of the energy was evaluated. In conditions we considered an alternative machine-technological solutions used for the final disposal of persistent organic pollutants resulting from the waste combustion in terms of additional operating costs and energy efficiency.

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Liljeroos, Tom. "Är saltglaseringsindustrin en källa till tidig organokloridförekomst?" Thesis, Halmstad University, School of Teacher Education (LUT), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-2365.

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Abstract.

The levels of dioxin and comparable substances rose to a large extent in our environment during the second half of the 20'Th century. This was the result of the synthesis of, and careless usage of these substances in cooling fluids, hydraulics, pesticides etc.

Background levels of dioxins and furans in sealed samples prior to this era suggest that former sources of these substances existed.

Salt glazing is a method of adding a smooth acid resistant exterior to stoneware ceramics. The technique has been in use since the 16'Th century, maybe even earlier than that. Some sources date the origin of the technique to the 13'Th century. Salt glazed ceramics were the prime type of industrial vessels and it was extensively used for food preservation in households from the 17'Th century to the early/mid 20'Th century.

The method was/is primarily used by Germany, Great Britain, America and Sweden.

Salt glazing is a source of graphite structures from soot, and of chlorine gas. Hence, the formation of organochlorides should be able to occur.

The reports main objective is to highlight the question; “Could the salt glazing industry be one of the sources to early dioxin emissions?” Secondary objectives are to present an introduction to dioxin and comparable substances, methods of analysis and symptoms of exposure.

The salt glazing industry is much likely one of the anthropogenic sources of early PCDD/F emissions. Though emission levels seem to be quite low, due to the persistence of PCDD/F noticeable levels could have accumulated. When the Leblanc soda process (a known source of PCDD/F) was introduced in 1791, the salt glazing process had already been used for nearly three hundred years.

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Sewart, Andrew Paul. "The fate and behaviour of polychlorinated dibenzo-p-dioxins, dibenzofurans and polychlorinated biphenyls in sewage sludge : amended agricultural soils and their potential transfer into terrestrial foodchain via lactating cattle". Thesis, Lancaster University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261004.

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Aurell, Johanna. "Effects of Varying Combustion Conditions on PCDD/F Formation". Doctoral thesis, Umeå universitet, Kemi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1795.

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Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are by-products emitted from combustion sources such as municipal solid waste (MSW) incineration plants. These organic compounds are recognized as toxic, bioaccumulative and persistent in the environment. PCDD/Fs are removed from flue gases before released from MSW incineration. However, the PCDD/Fs are not destroyed but retained in the residues, thus in the environment. Understanding the pathways that lead to their formation is important in order to develop ways to suppress their formation and prevent their release into the environment. Suppressing the formation can also allow less expensive air pollution control system to be used, and/or the costs of thermally treating the residues to be reduced. The main objective of the studies underlying this thesis was to elucidate process, combustion and fuel parameters that substantially affect the emission levels and formation of PCDD/Fs in flue gases from MSW incineration. The experiments were conducted under controllable, realistic combustion conditions using a laboratory-scale reactor combusting artificial MSW. The parameter found to most strongly reduce the PCDD/F emissions, was prolonging the flue gas residence time at a relatively high temperature (460°C). Increasing the sulfur dioxide (SO2) to hydrogen chloride (HCl) ratio to 1.6 in the flue gas was also found to reduce the PCDF levels, but not the PCDD levels. Fluctuations in the combustion process (carbon monoxide peaks), high chlorine levels in the waste (1.7%) and low temperatures in the secondary combustion zone (660°C) all tended to increase the emission levels. The PCDD/PCDF ratio in the flue gas was found to depend on the chlorine level in the waste, fluctuations in the combustion process and the SO2:HCl ratio in the flue gas. The formation pathways were found to be affected by the quench time profiles in the post-combustion zone, fluctuations in the combustion process and addition of sulfur. In addition, increased levels of chlorine in the waste increased the chlorination degrees of both PCDDs and PCDFs. A tendency for increased SO2 levels in the flue gas to increase levels of polychlorinated dibenzothiophenes (sulfur analogues of PCDFs) was also detected, however the increases were much less significant than the reduction in PCDF levels.

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Åberg, Annika. "Fate and exposure assessment of PCDD/Fs at contaminated sites". Licentiate thesis, Umeå University, Chemistry, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-5717.

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Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzo-furans (PCDFs) belong to the most toxic compounds known to science and they are defined as Persistent Organic Pollutants (POPs) under the Stock-holm Convention. The general human exposure to PCDD/Fs is primarily through dietary intake. The importance of contaminated sites as secondary PCDD/F sources (i.e. sources that once received its contamination from a primary source) are getting increased attention. To be able to assess the risks for human exposure at PCDD/F contaminated sites, the environmen-tal distribution of PCDD/Fs and the potential mobilization between dif-ferent environmental media (e.g. food chain transfer) must be known. The primary aim of the work presented in this thesis was to investigate human exposure pathways associated with PCDD/F contaminated sites by combining field measurements and modeling. Site specific field measurements were made at a PCDD/F contaminated site in Sweden and multimedia modeling scenarios were evaluated against site specific data and national reference data.

The results show that the congener distributions in exposure media affected by contaminated soil may differ significantly from the distribu-tions found in media from reference locations. Higher chlorinated PCDD/Fs may be transferred into food chains where they contribute to a large fraction of the toxic equivalent concentration (TEQ). Ingestion of locally produced animal food may be an important exposure pathway al-ready at low or moderate PCDD/F soil concentrations. However, the con-gener composition of the source is critical for the exposure. The signifi-cance of the individual exposure routes varies depending on e.g. the spatial distribution and magnitude of the soil contamination, the pro-perties of the exposure media and the human behavior. Multimedia mo-deling can be used in risk assessments as long as model algorithms and model parameters are representative for the superhydrophobic properties of PCDD/Fs. However, selection of physical-chemical PCDD/F properties is a challenge due to large variation in reported values. For some proper-ties, data is scattered or completely lacking

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Lundin, Lisa. "Formation and degradation of PCDD/F in waste incineration ashes". Doctoral thesis, Umeå : Department of Chemistry, Umeå University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1395.

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Del, Rio Gomez Iliana Maria. "Reproductive outcomes in people contaminated by PCBs/PCDFs, organohalogens in the Yucheng accident". Thesis, London School of Hygiene and Tropical Medicine (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407767.

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Garcia, Cleiton da Gama. "Uma arquitetura para contribuir com a acessibilidade de PCDVs explorando a internet das coisas". Universidade Catolica de Pelotas, 2016. http://tede.ucpel.edu.br:8080/jspui/handle/tede/597.

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The Ubiquitous Computing, also called UbiComp, has as premise to incorporate computational devices in all places, and active at all times, helping the human in a natural way, and as transparent as possible, minimizing the requirement of intervention of its user, and adjusting its behavior according to the current state of the context of interest of the user. The idea is that, more and more, the physical and digital worlds become one, where services will be offered to users through devices distributed by the environment. Contributing to the materialization of this integration, we have the growing availability of wired or wireless computer networks through which devices can communicate by sharing their contextual states. With this significant growth in connectivity levels, the Internet of Things (IoT) has now been consolidated. In spite of the growing technological development, it was verified the existence of few solutions at the national level that contribute to the freedom of mobility of PCDVs. Considering also that the number of PCDVs in Brazil reaches the significant number of 18.60 % of the population (IBGE, 2010), the central motivation for the creation of the HELIX Project arises, as an approach to promote the accessibility of visually impaired people. Considering this same motivation, the Rectory of the Catholic University of Pelotas, sought the Master’s Degree course in Electronic Engineering and Computing, requesting the development of an alternative focused on serving the members of its community with visual impairment. This promoted that the present dissertation constituted the first academic work of Project HELIX. This dissertation was developed with the general objective of contributing to the Accessibility of PCDVs through a hardware and software architecture that employs the principles of Contextaware Computing, Mobile Computing and the Internet of Things. The design effort of the HELIX Project will consider the software architecture of the EXEHDA middleware as well as its operational principles. The results achieved were promising, and point to the continuity of study and research efforts
A Computação Ubíqua, também chamada de UbiComp, tem como premissa incorporar dispositivos computacionais em todos os lugares, e ativos em todos os momentos, auxiliando o ser humano de forma natural, e o mais transparente possível, minimizando a exigência de intervenção de seu usuário e ajustando o seu comportamento de acordo com o estado atual do contexto de interesse do usuário. A ideia é que, cada vez mais, o mundo físico e o digital se tornem um só, onde serviços serão oferecidos para os usuários através de dispositivos distribuídos pelo ambiente. Contribuindo para a materialização desta integração, tem-se a crescente disponibilização de redes de computadores com ou sem fio através das quais dispositivos podem se comunicar compartilhando seus estados contextuais. Com este significativo crescimento dos níveis de conectividade, vem se consolidando atualmente a Internet das Coisas (IoT). Apesar do crescente desenvolvimento tecnológico, constatou-se a existência de poucas soluções no âmbito nacional que contribuam com a liberdade de mobilidade das Pessoas Com Deficiência Visual (PCDVs). Considerando também que, o número de PCDVs no Brasil atinge a significativa cifra de 18,60 % da população (IBGE, 2010), surge a motivação central para a criação do Projeto HELIX, enquanto uma abordagem para promover à acessibilidade de portadores de deficiência visual. Sensível a esta mesma motivação a Reitoria da Universidade Católica de Pelotas, procurou o Mestrado de Pós-Graduação em Engenharia Eletrônica e Computação solicitando o desenvolvimento de uma alternativa focada em atender os membros de sua comunidade com deficiência visual. Isto promoveu que a presente dissertação constituísse o primeiro trabalho acadêmico do Projeto HELIX. Esta dissertação foi desenvolvida com objetivo geral de contribuir para com a acessibilidade de PCDVs através de uma arquitetura de hardware e software que emprega os princípios da Computação Ciente de Contexto, da Computação Móvel e da Internet das Coisas. O esforço de concepção do Projeto HELIX considera a arquitetura de software do middleware EXEHDA, bem como seus princípios operacionais. Os resultados atingidos se mostraram promissores, e apontam para continuidade dos esforços de estudo e pesquisa.

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Fàbrega, Bonadona Francesc. "Physiologically-Based Pharmacokinetic (Pbpk) Modeling of Pcdd/Fs and Pfass in Humans". Doctoral thesis, Universitat Rovira i Virgili, 2014. http://hdl.handle.net/10803/284035.

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Els models farmacocinètics (PBPK) són representacions matemàtiques del cos humà, que tenen com a objectiu calcular la concentració de compostos químics en els teixits humans. Els models PBPK poden millorar el càlcul del risc per a la salut humana, però de moment no han estat escassament utilitzats. Entre els compostos ambientals més perillosos per a la salut humana destaquen les dibenzo-p-dioxines policlorades i dibenzofurans policlorats (PCDD/Fs) i els compostos perfluorats (PFASs). L’objectiu de la present tesis es el desenvolupament de un model PBPK per calcular la concentració de PCDD/Fs i PFASs en teixits humans. Prèviament al desenvolupament del model PBPK, es va desenvolupar un índex de risc utilitzant mapes auto-organitzats (SOM), per calcular els compostos ambientals més perillosos per a la salut humana. Entre els compostos més perillosos es van trobar els PFASs. Després es va desenvolupar el model PBPK per predir les concentracions de PCDD/Fs en sang i en teixit adipós. Els resultats finals van ser altament coincidents amb els resultats experimentals trobats a l’àrea de Tarragona (NE d’Espanya), y per això es va considerar el model com a validat. A continuació el model es va adaptar per calcular les concentracions de PFASs. Per això, primer es va adaptar el model per PFOS i PFOA, que són els compostos perfluorats més estudiats en la literatura, i després es va estendre el model a 9 PFASs més. Finalment, es va fer un anàlisis de la incertesa del model PBPK, i la incertesa paramètrica es va estudiar visual i estadísticament.
Los modelos farmacocinéticos (PBPK) son representaciones matemáticas del cuerpo humano, que tienen como objetivo calcular la concentración de químicos en los tejidos humanos. Los modelos PBPK pueden mejorar el cálculo de riesgo para la salud humana, pero hasta el momento no han sido muy usados. Entre los compuestos ambientales más peligrosos para la salud humana destacan las dibenzo-p-dioxinas policloradas y los dibenzofuranos policlorados (PCDD/Fs) y los compuestos perfluorados (PFASs). El objetivo de la presente tesis es el desarrollo un modelo PBPK para calcular la concentración de PCDD/Fs y PFASs en tejidos humanos. Previo al desarrollo del modelo PBPK se desarrolló un índice de riesgo usando mapas auto-organizados (SOM), para calcular los compuestos ambientales más peligrosos para la salud humana. Los PFASs se encontraron entre los compuestos de más riesgo. Después se desarrolló el modelo PBPK para predecir las concentraciones de PCDD/Fs en sangre y en tejido adiposo. Los resultados finales fueron muy coincidentes con los resultados experimentales encontrados en el área de Tarragona (NE de España), y por esta razón el modelo se consideró como validado. A continuación el modelo se adaptó para calcular las concentraciones de PFASs. Para ello, primero se adaptó el modelo para PFOS y PFOA, que son los compuestos perfluorados más estudiados en la literatura, y después se extendió el modelo a otros 9 PFASs. Finalmente, se hizo un análisis de la incertidumbre del modelo PBPK, y la incertidumbre paramétrica se estudio visual y estadísticamente.
Physiologically based pharmacokinetic (PBPK) models are mathematic representations of the human body that aims to assess the time course distribution of chemicals in human tissues. PBPK models may improve the assessment of human health risk but until now were not well studied. Among the most harmful environmental pollutants for human health there are polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and perfluoroalkyl substances (PFASs). The objective of the present work is to develop a PBPK model to assess the time course concentration of PCDD/Fs and PFASs in human tissues. Previously to the PBPK model development, a ranking index was developed using self-organizing maps (SOM) to assess the most harmful environmental contaminants, being PFASs among the most harmful compounds. After that, the PBPK model was developed to assess and predict the concentration of PCDD/Fs in human blood and adipose tissue. The final outcomes were very coincident with the experimental data found in Tarragona County (NE of Spain), and the model was considered as a validated. After that, the model was adapted to assess the concentrations of PFASs. Firstly the model was developed for PFOS and PFOA, that are the most studied compounds in the research literature, and then the model was expended to 9 PFASs more. Finally the uncertainty analysis of the PBPK model was conducted, and the parametric uncertainty was visually and statistically studied.

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Macnamara, Aine. "The role of psychological characteristics of developing excellence (PCDEs) in negotiating the pathway to excellence". Thesis, University of Central Lancashire, 2010. http://clok.uclan.ac.uk/19007/.

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The development of talent is a complex process mediated by a host of psychology, social, physical, and environmental variables. Unfortunately, the multiple processes involved in talent development (Gagne, 2004; Simonton, 2001) are frequently ignored by the systems and protocols employed in sport. Modem approaches to talent development are beginning to stress the initial possession, then subsequent development, of Psychological Characteristics of Developing Excellence (PCDEs; MacNamara, Button, & Collins, 2010) as the best way to realize latent potential. Accordingly, the aim of this thesis was to acknowledge this complexity by identifying the psycho-behavioural factors that co-act with physical potential and practice regimes to enhance the efficacy of TID models in sport. The main objectives of this thesis were: 1. To identify the challenges faced along the pathway to excellence and the PCDEs that facilitate the successful negotiation of the pathway to excellence across different performance domains. 2. To identify whether PCDEs are operationalised differentially depending, on an individual's age, stage, and context. 3. To confirm these differential roles through quasi-longitudinal examinations of longterm employment (in musicians) and across a key transition (in athletics, the transitions to university at 18 years of age). 4. To develop a questionnaire to bridge the theory-practice divide in TO processes and enable formative evaluation of PCDEs by practitioners. 5. To provide preliminary validation of the questionnaire by evaluating its discriminant function between good and poor development athletes. The development of talent is a complex process mediated by a host of psychology, social, physical, and environmental variables. Unfortunately, the multiple processes involved in talent development (Gagne, 2004; Simonton, 2001) are frequently ignored by the systems and protocols employed in sport. Modem approaches to talent development are beginning to stress the initial possession, then subsequent development, of Psychological Characteristics of Developing Excellence (PCDEs; MacNamara, Button, & Collins, 2010) as the best way to realize latent potential. Accordingly, the aim of this thesis was to acknowledge this complexity by identifying the psycho-behavioural factors that co-act with physical potential and practice regimes to enhance the efficacy of TID models in sport. The main objectives of this thesis were: 1. To identify the challenges faced along the pathway to excellence and the PCDEs that facilitate the successful negotiation of the pathway to excellence across different performance domains. 2. To identify whether PCDEs are operationalised differentially depending, on an individual's age, stage, and context. 3. To confirm these differential roles through quasi-longitudinal examinations of longterm employment (in musicians) and across a key transition (in athletics, the transitions to university at 18 years of age). 4. To develop a questionnaire to bridge the theory-practice divide in TO processes and enable formative evaluation of PCDEs by practitioners. 5. To provide preliminary validation of the questionnaire by evaluating its discriminant function between good and poor development athletes. The development of talent is a complex process mediated by a host of psychology, social, physical, and environmental variables. Unfortunately, the multiple processes involved in talent development (Gagne, 2004; Simonton, 2001) are frequently ignored by the systems and protocols employed in sport. Modem approaches to talent development are beginning to stress the initial possession, then subsequent development, of Psychological Characteristics of Developing Excellence (PCDEs; MacNamara, Button, & Collins, 2010) as the best way to realize latent potential. Accordingly, the aim of this thesis was to acknowledge this complexity by identifying the psycho-behavioural factors that co-act with physical potential and practice regimes to enhance the efficacy of TID models in sport. The main objectives of this thesis were: 1. To identify the challenges faced along the pathway to excellence and the PCDEs that facilitate the successful negotiation of the pathway to excellence across different performance domains. 2. To identify whether PCDEs are operationalised differentially depending, on an individual's age, stage, and context. 3. To confirm these differential roles through quasi-longitudinal examinations of longterm employment (in musicians) and across a key transition (in athletics, the transitions to university at 18 years of age). 4. To develop a questionnaire to bridge the theory-practice divide in TO processes and enable formative evaluation of PCDEs by practitioners. 5. To provide preliminary validation of the questionnaire by evaluating its discriminant function between good and poor development athletes. To address the first and second objective, Chapter 3 describes a retrospective, qualitative study of the careers of elite performers. The findings of this study suggest that the pathway to excellence is complicated by the specific challenges faced within different performance domains. However, a similar set of PCDEs, albeit differentially deployed, were reported by all participants as facilitators of development. Chapters 4 and 5 employed a quasi-longitudinal research design to address Objective 3 - the differential deployment of PCDEs in particular contexts. Using a sliding populations methodology, young classical musicians were tracked over a 2-year period to explore the PCDEs employed during the macro and micro stages they encountered as they progressed. A similar research design was employed in Chapter 4 to examine the use of PCDEs during a critical transitional period for track and field athletes. Although the results point to the generality of PCDEs at both elite and developmental levels, and across performance domains, there appeared to be an understandable and necessary shift in responsibility from significant others promoting and reinforcing PCDEs in the early years towards self-initiated and autonomous behaviours in the later years; in essence, a shift in the source of regulation (Cleary & Zimmerman, 2001). The studies in Chapters 3, 4, and 5 generated a list of PCDEs that facilitated development, along with an understanding of how PCDEs were deployed differentially along the pathway to excellence. These findings were used to develop the Psychological Characteristics of Developing Excellence Questionnaire (PCDEQ); a questionnaire designed to assess the possession and strategic deployment of the PCDEs. Chapter 6 reported the systematic generation of questionnaire items and an exploratory factor analysis that resulted in a 59- item, 6 factor stnicture PCDEQ. The PCDEQ displayed good psychometric properties and should provide coaches with a theoretically and empirically supported tool to assess, monitor, and develop these key developmental skills. To address the final objective, Chapter 7 presents a discriminant function analysis which revealed that the PCDEQ had very good discriminant function and was able to classify between 67 per cent and 75 per cent of athletes correctly on the basis of their self-reported behaviour in sport. In conclusion, the studies reported in this thesis provide a significant contribution to current knowledge by shifting the fopus away from TID methods based on prediction and correlation towards a consideration of progress and behaviour during development. Future recommendations include the need for further validation of the PCDEQ as well as longitudinal and action-based research assessing the role of PCDEs in talent development.

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Cornea, Flavia. "Evaluation of an alternative extraction method of PCDD/Fs from flue gas samples". Thesis, Umeå universitet, Kemiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-124550.

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Silva, Joice de Oliveira Epif?nio da. "A inser??o de pessoas com defici?ncia no mercado de trabalho: os sentidos da Lei de Cotas para os gestores de Recursos Humanos da regi?o metropolitana do Rio de Janeiro". Universidade Federal Rural do Rio de Janeiro, 2017. https://tede.ufrrj.br/jspui/handle/jspui/2456.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
Law No. 8213/91, known as the Quota Law was formulated as a tool to implement the National Policy on Employment Dues for Persons with Disabilities. This law today is one of the main means for the insertion of PCDs (Persons with Disabilities) into the labor market. However, the implementation of this law occurs in the face of some difficulties, such as accessibility, for example, in addition to prejudice regarding PCDs in the social environment, which ultimately interferes with its effectiveness. The purpose of this paper is to understand the meanings attributed to the Quota Law by HR Managers who act or have acted in organizations that apply the Quota Law. In order to achieve this goal, nine interviews were conducted, of which eight interviews were conducted with managers, some of whom were in full exercise until the date of the interview, and others who had recently left the organization in which they performed HR functions, and was also interviewed the coordinator of the State Nucleus for Assistance to the Disabled (NEAD). Besides the interviews, this work made use of the technique of observation and the analysis of the collected material occurred through the Nuclei of Meaning. The results show that the managers interviewed still perceive the Quota Law as a merely punitive Law, however, they understand the Quota Law also, as an important one, if not unique, tool for the insertion of PCDs into the labor market. With this, it can be said that the meanings that managers attribute to the Quota Law are loaded with prejudice and the way the Quota Law is signified by these managers reflects in the way they execute this Law, and it can be affirmed that the issue is cultural.
A lei n? 8213/91, conhecida como Lei de Cotas foi formulada como ferramenta para implementar a Pol?tica Nacional de Cotas Empregat?cias para Portadores de Defici?ncia. Esta lei hoje ? um dos principais meios para a inser??o das PCDs (Pessoas com Defici?ncia) no mercado de trabalho. Contudo, a implementa??o desta lei ocorre diante de algumas dificuldades, como a acessibilidade, por exemplo, al?m do preconceito no que tange ?s PCDs no meio social, o que acaba interferindo na efetividade da mesma. Este trabalho tem como objetivo, compreender os sentidos atribu?dos ? Lei de Cotas pelos Gestores de RH que atuam, ou atuaram, em organiza??es que se aplica a Lei de Cotas. Para atingir este objetivo foram realizadas nove entrevistas, sendo oito entrevistas realizadas com gestores, dos quais alguns estavam em pleno exerc?cio da fun??o at? a data da entrevista e outros que haviam sa?do recentemente da organiza??o em que exercia a fun??o de gestor de RH, e ainda, foi entrevistada a coordenadora do N?cleo Estadual de Atendimento ao Deficiente (NEAD). Al?m das entrevistas este trabalho fez uso da t?cnica de observa??o e a an?lise do material levantado ocorreu por meio dos N?cleos de Significa??o. Os resultados mostram que os gestores entrevistados ainda percebem a Lei de Cotas como uma Lei meramente punitiva, entretanto, entendem a Lei de Cotas tamb?m, como uma importante, sen?o ?nica, ferramenta para a inser??o das PCDs no mercado de trabalho. Com isso, pode-se afirmar que os sentidos que os gestores atribuem a Lei de Cotas s?o carregados de preconceito e a forma como a Lei de Cotas ? significada por esses gestores reflete na forma como executam essa Lei, e ainda, pode-se afirmar que a quest?o ? cultural

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Rey, Martínez María Dolores. "Formación de PCDD/Fs y otros contaminantes en procesos térmicos: aprovechamiento de biomasa y motores de combustión interna". Doctoral thesis, Universidad de Alicante, 2014. http://hdl.handle.net/10045/41125.

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Plch, Michal. "Návrh technologické jednotky pro odstraňování perzistentních látek při termickém zpracování kontaminované biomasy". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228708.

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The Diploma’s work deals with design to use new methods of cleaning the combustion products for the incinerator of biomass, which guarantees removal of dioxins from the combustion products. Thesis depicts methods of cleaning the combustion products, like ADIOX, using ceramic filters, catalytically filters and methods REMEDIA. Thesis compares constituent methods in terms of effectiveness and according to economic analysis applicable to incinerator of biomass-power output 1 MW. Thesis acquaints with the conception of biomass and with thermic processing, which produces dioxins. Thesis processes using biomass in Czech Republic and plan for using in the future. Thesis processes detailed model of filter using the fabric filters REMEDIA. Suggestion of position of the filter and it is connection to original products line of cleaning the combustion products. Increased pressure loss of the new pipework way and increased consumption of ventilator incinerator is calculated for the new connection. In quest of decreasing the thermal loss of combustion products and in quest of increasing safety of operation is calculated and in quest of increasing safety of operation is calculated proposal of isolation for the filter and pipework. In the end of the thesis is depicted using the technology for decreased amount of dioxins from the fly ash from dioxin filter.

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Al, Mamoon Hassan. "Evaluation of the separation capacity of different GC columns for tetra- to octachlorinated PCDD/Fs". Thesis, Umeå universitet, Kemiska institutionen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-68387.

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Sircar, Robin. "Untersuchung der Emissionen aus Einäscherungsanlagen und der Einsatzmöglichkeiten von Barrierenentladungen zur Verringerung des PCDD/F-Austrages". [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965442683.

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趙俊雄. "Modeling for production of dioxin (PCDDs) and furane (PCDFs) during incineration". Thesis, 1999. http://ndltd.ncl.edu.tw/handle/18445280271200180035.

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Jenn-Yan, Wu, i 吳振炎. "The Research of Dioxin (PCDDs) & Furan (PCDFs) Formation Mechanism In Medical Waste Incinerator". Thesis, 2001. http://ndltd.ncl.edu.tw/handle/11125197709467699912.

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碩士
國立中正大學
機械系
89
KEYWORD:Medical waste,incinerator,pyrolysis,dioxin,furan We discuss mainly the of Dioxin (PCDDs) and Furan (PCDFs) when the medical waste is on fire .And study and confer the combustible method and control of medical waste our country and foreign developed country counter ,and the prevention and reduction of the production presently . Analyze the condition of pyrolysis when medical waste in the incinerator, and compare with experiments and the production of different composition of gas under different operational conditions. And to build the analyzed models of theory, wish to understand the formation mechanism of Dioxin and Furan while medical waste pyrolysed in incinerator. And then find better and economic method to handle to achieve the goal to reduce harmful waste gas. We analyzed the models of chemical reaction and chemical equilibrium in order to build combustion analysis model , and use the relationship between equilibrium constant(Kc),temperature(K),emissions of hydrogen chloride(HCl) and excess air(γ) then to find the ways of controlling.

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YANG, TO HAO, i 涂浩洋. "The Study of relation Between Dioxin (PCDDs) and Precursor". Thesis, 2002. http://ndltd.ncl.edu.tw/handle/86482727006304393097.

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Abreu, Carolina Mariana Pinto. "Dibenzodioxinas policloradas e dibenzofuranos policlorados em leite materno". Master's thesis, 2017. http://hdl.handle.net/10316/83696.

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Relatório de Estágio do Mestrado Integrado em Ciências Farmacêuticas apresentado à Faculdade de Farmácia
O presente relatório de estágio em farmácia comunitária, tem como objetivo descrever e avaliar o estágio curricular, realizado na Farmácia Nova da Penteada, na Região Autónoma da Madeira, através de uma análise SWOT. Esta análise contempla os pontos fortes, os pontos fracos, as oportunidades e as ameaças, inerentes ao estágio.O presente relatório de estágio em farmácia hospitalar, tem como objetivo descrever e avaliar o estágio curricular, realizado no Serviço de Saúde da Região Autónoma da Madeira, E.P.E., através de uma análise SWOT. Esta análise contempla os pontos fortes, os pontos fracos, as oportunidades e as ameaças inerentes ao estágio.As dibenzodioxinas (PCDDs) e os dibenzofuranos (PCDFs) são poluentes orgânicos persistentes (POPs), ambientalmente estáveis. São subprodutos de várias reações químicas e térmicas, e acumulam-se na cadeia alimentar por serem compostos lipofílicos. Os PCDD/Fs são tóxicos para o organismo humano e armazenam-se nos reservatórios de gordura. O leite materno é utilizado como biomarcador dos níveis de resíduos, porque reflete a carga corporal maternal de poluentes e a exposição potencial dos lactentes. Além disso, o leite materno é rico em lipídos, é um método não-invasivo e fácil de ser recolhido. Vários estudos em diferentes países apresentam os níveis de equivalente de toxicidade (EQTs) no leite materno, permitindo assim, obter uma análise sobre a exposição da população. As implicações para a saúde das crianças dependem das concentrações de resíduos a que estão expostas. São observadas alterações no crescimento e imunológicas, perturbações endócrinas e no desenvolvimento neurológico das crianças. Os PCDD/Fs são extraídos, purificados, detetados e quantificados por várias metodologias analíticas. O principal método de deteção e quantificação é a cromatografia gasosa de alta resolução/espetrometria de massa de alta resolução (CGAR/EMAR). Apesar da ingestão de PCDD/Fs pela amamentação ter efeitos deletérios nas crianças, a amamentação tem inúmeras vantagens que provavelmente se sobrepõem aos aspetos negativos.
The present internship report on community pharmacy, aims to describe and evaluate the curricular internship, performed at “Farmácia Nova da Penteada”, through a SWOT analysis. This analysis considers the strengths, weaknesses, opportunities and threats associated with the internship.The present internship report on hospital pharmacy, aims to describe and evaluate the curricular internship, performed at “Serviço de Saúde da Região Autónoma da Madeira, E.P.E.”, through a SWOT analysis. This analysis considers the strengths, weaknesses, opportunities and threats associated with the internship.Dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are persistent organic pollutants (POPs), environmentally stable. They are by-products from several chemical and thermal reactions and accumulate in the food chain because they are lipophilic compounds. PCDD/Fs are toxic to the human body and are stored in the fat reservoirs. Breast milk is used as a biomarker of lipophilic residues levels because it reflects the maternal body burden of pollutants and the potential exposure of infants. Furthermore, breast milk is rich in lipids and can be collected easily and non-invasively. Several studies in different countries present toxic equivalents (TEQs) levels in breast milk, thus allowing an analysis of the exposure of the population. The health implication of children depends on the concentration of residues to which they are exposed. Growth and immune changes, endocrine disorders and neurological development of children are observed. PCDD/Fs are extracted, purified, detected and quantified by several analytical methodologies. The main method of detection and quantification is high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS). Although the ingestion of PCDD/Fs through breastfeeding has deleterious effects on children, breastfeeding has numerous advantages that are likely to overlap with negative aspects.

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Gadomski, Damien. "Investigations into the presence of PCDDs in ball clay exhibiting the "natural formation" profile". 2005. http://etd.nd.edu.lib-proxy.nd.edu/ETD-db/theses/available/etd-03292005-005736/.

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Thesis (Ph. D.)--University of Notre Dame, 2005.
Thesis directed by Robert L. Irvine for the Department of Civil Engineering and Geological Sciences. "March, 2005." Includes bibliographical references (leaves 132-140).

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Wang, Po-Jen, i 王柏人. "The source/receptor relationship of PCDD/PCDFs identified by a trajectory model". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/45417259595937860757.

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碩士
中興大學
環境工程學系所
95
The Nantou County locates on the eastern site of Taichung city and on the western site of Central Mountain Range. Thus, it is easily to accumulate dioxin in Nantou with the air parcel transferred from western sources. Additionally, several incinerators have already operated in west Taiwan recently, and these also are important dioxins sources. For understanding dioxins characters and sources in the Nantou County, this study analyzes impact range and dioxins characters of near incinerators by measurement and GTx modeling. We considered eight major categories of PCDD/Fs emission sources and three different locations, to cover a wide range of sourcecharacteristic, PCDD/Fs congener profiles, meteorological conditions and terrain configurations. The atmospheric dioxins concentrations in suburban site, traffic arteries site and background station were 0.11, 0.17 and 0.0095 pg I-TEQ/m3, respectively. Moreover, the dioxins concentrations of the grass cut frequently were 0.18, 0.9 and 0.15 pg WHO-TEQ/g, and the dioxins concentrations of the grass cut ifnfrequently were 0.33, 1.5 and 0.13 pg WHO-TEQ/g with a moisture content of 12 %. The characteristic index and model simulations could be founded that suburban site was not only impacted by incinerators, electric arc furnaces and traffic source, but also impacted by copper and aluminum smelters. For traffic arteries station, the main sources were metropolitan solids wastes incinerators, medical wastes incinerators, sinter plants, electric arc furnaces, copper smelters, diesel-fueled vehicles and unleaded gas-fueled vehicles. The model also showed that pollutants were easily transferred into Chushan in north and northeast wind system. Therefore, the north wind system would facilitate the dioxins transporting into Chushan and Shuili, and leaded the dioxins concentrations increasing. This study showed that using the GTx model, atmospheric monitoring data, the pasture examination data and PCDD/Fs congener profiles can explicitly understand the relationship of PCDD/Fs between the source and the receptor.

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Huang, Tsai Fei, i 黃彩斐. "The Effects of Temperature and Gas Composition on the PCDD/PCDFs Formation in MSW Fly Ash". Thesis, 1998. http://ndltd.ncl.edu.tw/handle/89246431761760405897.

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碩士
國立中央大學
環境工程學系
86
In this study, fly ashes were sampled from three large-scale MSW (municipal solid waste) incinerators in Taiwan for analysis of dioxin contents. In addition to the investigation of dioxin contents of fly ash from MSW incinerators, our study also look into dioxin formation within the MSW incineration system via a laboratory-scale reactor. In this study, the effects of the reaction time, temperature, oxygen content in the gas stream and carbon content of fly ash on PCDD/Fs formation on fly ash were investigated. Three MSW incinerators investigated are equipped with different air pollution control device (APCD). Preliminary results indicated that 2,3,7,8-PCDD/Fs homologue patterns of various types of fly ash were quite similar for three MSW incinerators. The concentrations of higher chlorinating degree congeners of PCDDs and PCDFs were obviously higher than that of lower chlorinating degree congeners. The content of dioxin in fly ash would increase as the fly ash passed through APCD zone. In other words, the environment of APCD may actually increase the content of dioxin in fly ash. Dioxin concentration in fly ash for three MSW incinerators was MSW-C＜MSW-A＜MSW-B. About the formation experiments for dioxins in this study, the optimum temperature of dioxin formation for various fly ashes was different. The optimum temperatures was 350℃ for boiler ash, 300℃ for cyclone ash and 250℃ for ESP ash, respectively. Preliminary results indicated that the optimum temperature would increase with decreasing particle size. The dioxin content of fly ash was not significantly correlated with reaction time. As the O2 concentration was varied between 0~100％, the optimum oxygen content for dioxin formation was found at 7.5﹪for cyclone ash, and the PCDD/PCDF ratio increased with increasing (O2(. Therefore, the formation of PCDDs which contains two oxygen atoms are affected more significantly by (O2( than PCDF which contains only one oxygen atom. Dioxins formation was observed even for the gas containing no oxygen was passed through the fly ash. As a result, other formation routes which do not need O2 occur on fly ash, for example, the Ullmann condensation reaction, or O2 was provided from the precursor (oxygen-complex compound) originally existed in fly ash. The carboncontent in fly ash is varied between 0~20﹪in this study, and the results showed that the maximum formation was found at 5％. The dioxin formation rates with and without gas stream were compared, the latter process resulted in the larger amount of PCDD/Fs. In all experiments of this study, the concentration of dioxin is ESP ash＞cyclone ash＞boiler ash. The precursors were not injected into the fly ash or gas stream in all formation experiments, however, dioxin was still formed in fly ash. In other words, other chlorinated routes may exist on the fly ash surface in addition to Deacon reactions.Keywords： Dioxin, PCDD, PCDF, APCD, Temperature, Oxygen, Carbon content

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Yin, Ge. "Organohalogen contaminants in wildlife from the Yangtze River Delta : Development of methods and assessments of legacy and emerging persistent organic pollutants". Doctoral thesis, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-131986.

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Rapid economic development has occurred during the past few decades in China with the Yangtze River Delta (YRD) area as one of the most progressive areas. The urbanization, industrialization, agricultural and aquaculture activities result in extensive production and application of chemicals. Organohalogen contaminants (OHCs) have been widely used as i.e. pesticides, flame retardants and plasticizers. They are persistent, bioaccumulative and pose a potential threat to ecosystem and human health. However, limited research has been conducted in the YRD with respect to chemicals environmental exposure. The main objective of this thesis is to investigate the contamination level, distribution pattern and sources of OHCs in the YRD. Wildlife from different habitats are used to indicate the environmental pollution situation, and evaluate selected matrices for use in long term biomonitoring to determine the environmental stress the contamination may cause. In addition, a method is developed for dicofol analysis. Moreover, a specific effort is made to introduce statistic power analysis to assist in optimal sampling design. The thesis results show extensive contamination of OHCs in wildlife in the YRD. The occurrences of high concentrations of chlorinated paraffins (CPs) are reported in wildlife, in particular in terrestrial species, (i.e. short-tailed mamushi snake and peregrine falcon). Impurities and byproducts of pentachlorophenol products, i.e. polychlorinated diphenyl ethers (PCDEs) and hydroxylated polychlorinated diphenyl ethers (OH-PCDEs) are identified and reported for the first time in eggs from black-crowned night heron and whiskered tern. High concentrations of octachlorodibenzo-p-dioxin (OCDD) are determined in these samples. The toxic equivalents (TEQs) of polychlorinated dibenzo-p-dioxin (PCDDs) and polychlorinated dibenzofurans (PCDFs) are at mean levels of 300 and 520 pg TEQ g-1lw (WHO2005 TEQ) in eggs from the two bird species, respectively. This is two orders of magnitude higher than European Union (EU) regulation limit in chicken eggs. Also, a novel pattern of polychlorinated biphenyls (PCBs) with octa- to decaCBs, contributing to as much as 20% of total PCBs therein, are reported in birds. The legacy POPs shows a common characteristic with relatively high level of organochlorine pesticides (i.e. DDT, hexacyclohexanes (HCHs) and Mirex), indicating historic applications. In contrast, rather low concentrations are shown of industrial chemicals such as PCBs and polybrominated diphenyl ethers (PBDEs). A refined and improved analytical method is developed to separate dicofol from its major decomposition compound, 4,4’-dichlorobenzophenone. Hence dicofol is possible to assess as such. Statistic power analysis demonstrates that sampling of sedentary species should be consistently spread over a larger area to monitor temporal trends of contaminants in a robust manner. The results presented in this thesis show high CPs and OCDD concentrations in wildlife. The levels and patterns of OHCs in YRD differ from other well studied areas of the world. This is likely due to the extensive production and use of chemicals in the YRD. The results strongly signal the need of research biomonitoring programs that meet the current situation of the YRD. Such programs will contribute to the management of chemicals and environment in YRD, with the potential to grow into the human health sector, and to expand to China as a whole.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 5: Submitted. Paper 6: Manuscript.

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Tseng, Yi-hon, i 曾亦宏. "PCDD/Fs Distribution Characteristics". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/30737120076424258759.

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碩士
國立屏東科技大學
環境工程與科學系
91
Thermal destruction (i.e. incineration) is one of the most effective processes to treat municipal solid waste (MSW) in view of the volume reduction. However, the secondary pollutions come out from the incinerator is a conflict issue about this state-of-art technology. Formation of dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the flue gas and ash from the incineration system was recognized by two major pathways. One is incompletely destruction of the waste resources, the other is reformation by the precursors mechanism and de novo synthesis, respectively. Studies showed that the conditions in the post-combustion region are strongly influencing the formation these products of incomplete combustion (PICs). The favored temperature range and high surface area in the particulate matter play the important roles to increase the concentration of PCDD/Fs. The high removal efficiency of particulate active carbon injection was to apply for most of incineration systems to reduce the heavy metal compounds and PCDD/Fs. The adsorption carbon residue in the fly ash stream is still a controversial issue for the final disposal treatment. The preliminary investigation in this study is to analyze the physical and chemical characteristics of fly ash from two different thermal processes ( incinerator and steel arc furnace). The ash samples were collected at the units of air pollution control devices (APCDs). The results showed that PCDD/Fs concentration of fly ash is dependent on the chlorine contents and the active surface area. The comparison between the raw fly ash as received from the APCDs and the treated fly ash by the model precursors is made in this study. The operation parameters and the matrix of fly ash for the physical and chemical characteristics were investigated. Inducing precursors experiments took place in a laboratory scales packed bed reactor. Investigation of the correlation between the precursor compounds and the PCDD/Fs congeners profile is the trust of this study. The remaining PCDD/Fs in the matrix of fly ash would be demonstrated to understand the PCDD/Fs fate and the rate determining step during the PCDD/Fs formation and destruction. Based on these information, to identify the original PCDD/Fs pollution sources from the environmental medium may be possible.

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Lin, Sin-chiou, i 林欣萩. "Effect and contribution assessment of PCDD/Fs in forage from PCDD/Fs emission sources in Taiwan". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/89409309473403624583.

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碩士
國立成功大學
環境醫學研究所
95
Literatures showed that the higher PCDD/Fs levels in beef, mutton and milk were related to the higher PCDD/Fs levels in forages. Therefore, the establishment of clean and safe measures for forage production is too impatient to wait. Because of the livestock farm not only wide but scrappy, it will highly cost on manpower and economical recources by field survey in each place. This study is aimed to simulate the PCDD/Fs levels of forage from the pastures nearby the PCDD/Fs emission sources and to assess the contribution of those sources, and then establish the clean and safe zones for forage production. Three types of forage plant which are most commom used and planted on the livestock farm, Napiergrass, Pangolgrass and Silage Corn are selected to simulate PCDD/Fs levels. A and B County were chosen to be conducted in this study, because their high emissions of PCDD/Fs, high density of dairy farm and high production of forage. C county and D County were chosen as control area, because they also have wide pasture and less contaminated by PCDD/Fs. The basic information of pastures, dairy farm, PCDD/Fs emission sources and meteorological data were collected and the data were applied to simulate ambient levels and deposition of PCDD/Fs by atmospheric dispersion model (ISCST3). Then, the Multimedia model was applied to estimate the PCDD/Fs concentrations of environmental media and forage. The results were compared with the maximum limits for PCDD/Fs in feeding stuffs of EU. Finally, the spatial distribution of clean and safe pasture area were mapped by using the geographic information system (GIS). After comparing the simulated PCDD/Fs level to measured PCDD/Fs level of forage plants, the results show the range of their difference was acceptable. As above we could conclude that using multimedia model to simulate the PCDD/Fs level of forages in this study is practicable. The results of ambient PCDD/Fs level and total deposition by using ISC-ST3 atmospheric dispersion model reveal that A County was higher than others and D County was lowest. After using multimedia model to simulate the PCDD/Fs level of forages, we found that all counties have the lowest PCDD/Fs level of forage in winter. Besides, the simulated PCDD/Fs level of three kinds of forages in A County were higher than EU maximum limits (0.75 ng WHO98-TEQPCDD/F/kg, 12% H2O). We only included the PCDD/Fs emission data of the emission sources investigated by Taiwan EPA in this study, and the emission sources which not investigated by Taiwan EPA and some moving emission sources such as motorcycles, burning outdoors and flying dust from soil were excluded.

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Li, Hsing-Wang, i 李興旺. "Characterization of PCDD/F Emission from Industrial Thermal Processes". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/37920796071536918119.

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博士
國立成功大學
環境工程學系碩博士班
96
The emission of polychlorinated dibenzo-p-dioxin and furans (PCDD/Fs) from the different thermal processes was investigated. These thermal processes included aluminum smelting plant, electric arc furnace, fly ash treatment plant, and municipal solid waste incinerators. Seventeen PCDD/F congeners were measured by high resolution gas chromatography/mass spectrometer (HRGC/HRMS). The four secondary aluminum smelters (ALS) yield much higher PCDD/Fs than the aluminum ingot smelters, or 7.94-22.7 vs 0.57-2.67 ng/Nm3, due to a large percentage of waste or recycled aluminum used in the former and over 50% ingot used in the latter. The PCDD/F emission factor is related to either raw materials used or product produced, and the average emission factor of four secondary ALS is much higher than that of aluminum ingot smelters, or approximately 20 times higher based on either raw materials or product. The most important PCDD/F source of input mass in the fly ash treatment plant (the Waelz process) was EAF fly ash, which had a mean PCDD/F content of 18.51 ng/g and contributed more than 99% of the PCDD/F input mass. For the PCDD/F output mass, the major total PCDD/F content of 43.73 and 10.78 ng/g were in bag-filter- and cyclone-ashes, which accounted for about 69% and 17%, respectively. The O/I ratio of total PCDD/F mass and total PCDD/F I-TEQ were 0.62 and 1.19, respectively. Thus, the effects of the Waelz process for the depletion of total PCDD/F mass was positive but minor, while the effect for total PCDD/F I-TEQ was adverse overall. In the amount of 20, 40 and 50 kg/hr powder activated carbon (PAC) injection, the removal efficiencies of PCDD/Fs in the stack flue gas were 86%, 96% and 97%, respectively. By adding an increased amount of PAC, the removal efficiencies were enhanced while the reduction fractions of low chlorinated PCDD/F congeners were much higher than those of highly chlorinated PCDD/F congeners. The addition of bio-solution (NOE-7F) in the raw materials had a dechlorination on the PCDD/F removal and mainly inhibited highly chlorinated PCDD/F formation. The combination of both PAC injection and NOE-7F addition has a high potential for practical application. The usage of filters over the four-year period led to increases of the total I-TEQ levels after the bag filters by 98%-256%, in the three plants. After the replacement of filters, the total I-TEQ after the filters decreased by 53%-89%, in these plants. A great amount of PCDD/Fs were sorbed by the installed filters over four-year period and their subsequent release from filters led to increases of PCDD/Fs levels in the stack flue gases. The release of PCDD/Fs from filters resulted most likely from the blow-off of fine pieces of the aged filter material by the flue gas when the filter was used after a certain period. High PCDD/F concentrations after the filters are attributed conventionally to the memory effect of the filters. The results of this study showed that the raw materials played an important role to PCDD/F formation. Different air pollution control devices could reach different removal efficiency of PCDD/F. How to combine different air pollution control devices (APCDs) to reduce PCDD/F emission effectively is a critical issue. The PCDD/F concentration was measured regularly and replacement of filters or materials of APCDs was also necessary.

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Chen, Shiu-chou, i 陳仕洲. "PCDD/F Characteristic in the Exhaust of Mobile Sources". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/05714094044329176795.

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碩士
國立成功大學
環境工程學系碩博士班
96
For these years, mobile pollution emission sources have contributed more and more in domestic polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), This study examined the characteristics of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in the exhaust gases of mobile sources. In this study, 50 vehicles of petrol SUV car, 15 vehicles of diesel oil limousine, 2 heavy-duty diesel vehicles and 10 motorcycles were investigated. The PCDD/Fs emission factors of mobile sources were determined‚ and the overall emission quantity of PCDD/Fs from the domestic mobile sources was estimated. Finally, the influence of these emission sources on the surrounding environment was assessed. The total PCDD/F concentrations exhaust from SUV, diesel vehicles, heavy-duty diesel vehicles and motorcycles are 0.0553, 0.0417, 0.145 and 0.0591 ng I-TEQ/Nm3, respectively. The PCDD/F emission factors from SUV, diesel vehicles, heavy-duty diesel vehicles and motorcycles are 0.113, 0.105, 1.86 and 0.0831 ng I-TEQ/km, respectively. The particulate-phase of PCDD/Fs in the exhaust gases of SUV, diesel vehicles, heavy-duty diesel vehicles and motorcycles are 74.4%, 91.8%, 70.2% and 85.1%, respectively. Moreover, the mean I-TEQ concentration in particulate-phase is 79.8%. Due to the relatively high fraction of PCDD/Fs in particulate-phase, the PCDD/Fs emission can be effectively controlled by reducing the emission of particle in the exhaust gases of vehicles. After using new engine oil old engine oil, the PCDD/Fs concentrations in particulate-phase were reduced 38.2% (from 0.0445 to 0.0275 ng I-TEQ/Nm3) and 58.2%(from 0.0631 to 0.0264 ng I-TEQ/Nm3), respectively, for L type and N type mechanical bicycles. The emission factors of PCDD/F I-TEQ were also reduced 53.5% (from 0.141 to 0.0655 ng I-TEQ/km) and 56.6% (from 0.105 to 0.0456 ng I-TEQ/km), respectively, for L type and N type mechanical bicycles. The trend of PCDD/F concentrations and I-TEQ emission factors indicated that using the new engine oil can reduce the PCDD/Fs emission of vehicles. The research result shows the average PCDD/Fs concentrations in ambient air nearby M site (municipal solid waste incinerators [MSWIs]) is 0.0418 pg I-TEQ/Nm3, we compared cross-section of above PCDD/Fs with that inside the incinerator tunnels and SUV, diesel vehicles, heavy-duty diesel vehicles and motorcycles and found that there is no prominent relationship between cross-section characteristics of PCDD/Fs around the incinerators and inside their tunnels but cross-section characteristics of PCDD/Fs around the incinerators are so similar to out test vehicles. Therefore, we predict concentration of PCDD/Fs n ambient air nearby incinerators should be affected by mobile pollution emission sources which nearby them.

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Cheng, Pai-Sheng, i 鄭百乘. "Study of Environmental PCDD/Fs Fingerprints and Distribution in Taiwan". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/40544229198384656918.

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博士
國立清華大學
化學系
91
Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) are unwanted byproducts from various combustion processes and numerous chemical industrial processes. The toxic 2,3,7,8-substituted PCDD/Fs are lipophilic and tend to accumulate in carbon-rich matrices and in fatty tissues. PCDD/Fs have been detected in every environmental compartment owing to their chemical, physical and biological stability and long-range transport. Moreover, PCDD/Fs emissions from municipal solid waste incinerators (MSWIs) have become a globally environmental issue. Investigation of the relationship between PCDD/Fs level in stack emission from MSWIs and in ambient air, soil and vegetation provides the PCDD/Fs impact on environment from MSWI emissions. There are six chapters in this thesis. Chapter 1 describes the research motive and purposes. Chapter 2 introduces the methods of PCDD/Fs sampling, PCDD/Fs analysis, ISCST3 model, PCA and HCA statistics. The title of chapter 3 is “Comparative study of monitored levels of PCDD/Fs in ambient air, soil and ISCST3 model predictions in the vicinity of a municipal solid waste incinerator in Hsinchu”. As a result of the newly construction of Hsinchu city MSWI, this study seized a wonderful opportunity to research how PCDD/Fs emission from a new MSWI equipped with modern APCDs could impact the ambient environment. This chapter presents the PCDD/Fs measured in ambient air and in soil around Hsinchu city MSWI during the trial burns in 2000 and compared to those measured in 2001 when it was fully operational. Concentration discrepancies between instrumental quantification and ISCST3 model prediction of ambient air were examined to test the precision and correlation among these two different types of method. Results of PCA, HCA and ISCST3 prediction reveal that Hsinchu city MSWI is not the major PCDD/Fs emission source to the ambient region. Human activities and unknown PCDD/Fs sources may fill up the gap among the model predictions and the instrument measurements. A systematic decrease of PCDD/Fs concentration in the ambient air from the northeast area to southwest was observed. This decreasing trend along the direction of wind is attributed to the heavy industrial activities on the northeast of Hsinchu city and wind flow towards southwest. Higher PCDD/Fs levels in the ambient air were found during spring and lower concentration was observed in summer. We recommend monitoring MSWI on a regional basis where the industrial and human activities are dense as in Taiwan. The title of chapter 4 is “Distributions and principal sources of PCDD/Fs in ambient air, soil and vegetation in the vicinity of Taichung city and Chiayi city municipal solid waste incinerators together with an arc furnace in Kaohsiung”. Most related researches generally hypothesize a potential emission source at first, and measure the environmental PCDD/Fs levels in simply one or two kinds of matrices to evaluate the influences from targeted source. In this study, PCDD/Fs in four matrices including stack gas, ambient air, soil and vegetation were collected and analyzed from or in the vicinity of Taichung city MSWI, Chiayi city MSWI and one arc furnace in Kaohsiung city, respectively. The main purpose is to investigate the PCDD/Fs distributions in the three areas on the basis of regional viewpoint, and find out the major PCDD/Fs sources in the area. The determination of PCDD/Fs in leaves was carried out using modified and verified USEPA method 1613B. Different type of PCDD/Fs source in the respective investigation areas were proposed: 1. PCDD/Fs in the vicinity of Taichung city MSWI might because of the human activity like the case of Hsinchu MSWI; 2. medical waste incineration was probably the major PCDD/Fs source in the ambient environment of Chiayi city MSWI; 3. the arc furnace was considered one of the principal PCDD/Fs emission source to the surrounding environment in Kaohsiung Lin Hai industrial district. Furthermore, high PCDD/Fs amount occurred in soil resulting in positive correlation between TOC and PCDD/Fs content. It is suggested that banyan leaf could be selected as an atmospheric PCDD/Fs biomonitor in Taiwan. The title of chapter 5 is “Nationwide PCDD/Fs levels in ambient air, soil and vegetation in Taiwan”. Reported data/results from the existing survey projects and our lab were collected and integrated into the first “Taiwan Environmental PCDD/Fs Database” based on the UNEP guidance document. Taiwan is a small island populated with twenty-two million people in the west living in an area of 36,179 km2. High population density leads different human lives and activities comparative to the continental countries. For the first time, PCDD/Fs levels in ambient air, vegetation and soil around 19 MSWIs and samples from urban areas in Taiwan are discussed and summarized to bring up a nationwide view of dioxin distributions. Typically, correlation between PCDD/Fs levels in ambient air, soil and vegetation was not observed. The MSWIs are therefore not the only or major dioxin emission source. The Mucha MSWI showed clear influence on ambient PCDD/Fs concentrations, i.e. when comparing the previous and currently improved APCDs. Due to short of data, conclusions can not be made between human activity (population or industrial park) distributions and dioxin level distributions in Taiwan. It is suggested regional (county) basis monitoring instead of the measurements simply surrounding MSWIs, and extended to a nationwide monitoring system in the long run. The title of chapter 6 is “Investigation of meteorological factors influences on PCDD/Fs levels in ambient air using evidences from typhoons”. PCDD/Fs congener concentrations and profile in ambient air under stable weather condition have been proven readily altered by meteorological factors including temperature, wind, rain and air mass origin. However, little has been reported for the atmospheric PCDD/Fs condition right after severe weather variations. This is the first study aiming at the influences of meteorological factors on dioxin congener levels and distributions in ambient air exactly after typhoons. High rainfall and wind speed are both verified to reduce the PCDD/Fs level in ambient air, whereas rainfall influences the most. Relation between rain rate and reduced PCDD/Fs concentration in ambient air samples after typhoons was successfully correlated with an exponential growth curve. High wind speed eliminates the PCDD/Fs concentration in air immediately, but the affect of rain is usually reflected several hours later. PCDD/Fs levels in gaseous phase or particulate phase showed the same trend of variations. It is consequently suggested that both PCDDs and PCDFs in gaseous phase and in particular phase were persistently rose back to their original levels after the typhoon, but rainfall slow down the recovering speed in particulate phase. Severe meteorology factors altered the PCDDs to PCDFs ratio in ambient air, but not the profiles. Moreover, PCDD/Fs level in ambient air would revive in one or two days after the strict weather. These phenomena reveal that atmospheric PCDD/Fs level in Taiwan is not likely to become lower in summer or in autumn due to the prevalence of typhoon in these seasons. A long-term steady weather without heavy rain or high average wind speed is important during atmospheric PCDD/Fs measurement. If time and resources are permitted, chronic ambient air monitoring should be the best strategy to acquire faithful, representative and accurate data.

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Chen, Chien-Cheng, i 陳建呈. "Study the Catalytic Effects of Precursors for PCDD/Fs Formation". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/06786498972206022473.

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碩士
國立屏東科技大學
環境工程與科學系所
97
The precursors of Dioxin, such as chlorophenols, chlorobenzenes, and polycyclic aromatic hydrocarbons are combined with fly ash surface, the role catalytic metals, and a condensation reaction to form Dioxin compounds. A powdered activated carbon injection is used to effectively control and adsorb dioxin compounds in the flue. However, when the exhaust of the previous reaction is disturbed, small particles of fly ash may re-enter the air pollution prevention equipment to form dioxin and furan. In this study, the bag house of a waste incinerator was used in laboratory simulations. The results of the study show that adding 0.2% trichlorophenol onto fly ash forms a PCDD/Fs concentration of 27.9 ng/g, whereas adding 0.5% chlorobenzene onto fly ash forms a PCDD/Fs concentration of 8.3 ng/g. Therefore, the addition of trichlorophenol is more favorable than chlorobenzene because the trichlorophenol forms a dioxin concentration that is 2.4 times greater. Furthermore, adding 0.1% pentachlorophenol onto the fly ash produces a PCDD/Fs concentration of 142.2 ng/g, and adding 0.2% pentachlorophenol produces a PCDD/Fs concentration of 166.0 ng/g. Compared to the aforementioned trichlorophenol, the pentachlorophenol forms a dioxin concentration that is at least 4.1 times greater. Up to now, pentachlorophenol most effectively treats dioxin-type compounds in the flue. Also, increasing the concentration of pentachlorophenol subsequently increases the adsorbed concentration of PCDD/Fs. Further simulation revealed that the addition of mercurydichloride and trichlorophenol increased the PCDD/Fs concentration from 27.9 ng/g to 111.5 ng/g. Certainly, the mercurydichloride triples the adsorption of dioxin compounds. In conclusion, adding chlorophenol compounds, chlorobenzene, diphenyl furans, and polycyclic aromatic hydrocarbons onto fly ash generated positive trends of PCDD/Fs adsorption. The addition of chlorophenol compounds and polycyclic aromatic hydrocarbons resulted in large positive trends of PCDDs species adsorption. The addition of chlorobenzene and dibenzofurans resulted in large positive trends of PCDFs species adsorption.

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Guan-YuChen i 陳冠宇. "A Study on PCDD/Fs Scavenged by Cloud/Fog Water". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/793s3b.

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碩士
國立成功大學
環境工程學系
107
Precipitation is one of the important sedimentation mechanisms of pollutants in the atmosphere, but the literature of Dibenzo-p-dioxin and Dibenzofuran (PCDD/Fs) deposition in cloud/fog water is still absent. However, droplets of cloud/fog water are much smaller and have a much higher surface-to-volume ratio compared to rain which might make it more efficiency in PCDD/F sedimentation. Therefore, we investigate PCDD/Fs scavenged by cloud/fog water in this study in order to figure it out. Sequential cloud/fog water samples were collected for each cloud event during January 17th to February 24th, 2018 and January 15th to February 16th, 2019. The cloud water samples were combined into one to reach 20 L for PCDD/F measurement due to the low solubility of PCDD/Fs in water. There were 3 and 11 events happened during collecting period in 2018 and 2019, respectively, but only 8 events were analyzed in 2019 because of too short cloud/fog water event period or too low liquid water content. On the other hand, the ambient air sample were collected during January 14th and 28th, 2019, with 7 samples. Total PCDD/F-WHO-TEQ concentration collected by active fog collector in cloud/fog water samples in 2019 (mean: 1.35±1.80 pg WHO-TEQ L-1) averaged higher than the values of passive one (mean: 0.769±1.23 pg WHO-TEQ L-1). There might mix with a little bit rain in cloud/fog water sample collected by passive fog collector, which made liquid water content (LWC) for passive fog collector larger than LWC for active one. Compared to scavenging coefficient of PCDD/F-WHO-TEQ of passive fog collector (mean: 2.24×105±2.96×105), scavenging coefficient (C-cloud/C-air) of PCDD/F-WHO-TEQ of active one was larger (mean: 4.20×105±3.60×105) in 2019. The cause of PCDD/F scavenging coefficient difference contributed to cloud/fog water sample mixing with rain which collected by passive fog collector. Besides, scavenging coefficient of PCDD/F-WHO-TEQ of passive fog collector in 2018 (mean: 3.20×105±3.26×105) averaged higher than the results of passive one in 2019 due to rich cloud and fog during collecting period in 2018. Then, compared to PCDD/F scavenging coefficient of precipitations (around 1.9×105), the scavenging coefficient of cloud/fog water in 2019 was larger. On the other hand, compared to scavenging ratio of PCDD/F-WHO-TEQ of passive fog collector (mean: 0.056±0.074), scavenging ratio (C-cloud/C-air *LWC) of PCDD/F-WHO-TEQ of active one was lower (mean: 0.033±0.029) in 2019. The reason might connect with higher LWC of passive fog collector where PCDD/Fs in the atmosphere could be scavenged by more cloud/fog water and rain. Besides, scavenging ratio of PCDD/F-WHO-TEQ of passive fog collector in 2018 (mean: 0.254±0.236) averaged higher than the results of passive one in 2019 due to higher LWC and rich cloud and fog during collecting period in 2018. Additionally, PCDD/F scavenging ratio of cloud/fog water was smaller than that of trace elements (ranged from 0.11- 0.56) since trace elements are easier to dissolve in water than PCDD/Fs. In conclusion, the obtained scavenging ratios of PCDD/Fs by cloud/fog water are crucial for clarifying the effect of cloud/fog water on the deposition of atmospheric PCDD/Fs.

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Chen, Che kuan, i 陳哲寬. "Characteristics of size distribution of PCDD/Fs and heavy metals in bottom ash and mass distribution of PCDD/Fs in the selected municipal solid waste incinerators". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/50228623027612930557.

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博士
國立屏東科技大學
環境工程與科學系所
96
This study investigated the size distribution of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and heavy-metals in bottom ash from four selected municipal solid waste incinerations (MSWIs). The weight fractions of bottom ashes in different particle sizes were also investigated. Finally, PCDD/F mass distributions in the whole incinerator during start-up process have been addressed as well. The significant conclusions of this study are as follows: 1. The major peak in the particle size distribution for bottom ash of MSWI A was found in a particle size of 1 to 2.36 mm, where the weight percentage was 33.2%. For MSWIs B, C and D, the major peak was all located at the particle size range the 2.36–4.75 mm, where the weight percentages were 31.7%, 38.9% and 28.4%, respectively, with averaged 33.0%. 2. For the four selected MSWIs, the major peak in the particle size distribution for the PCDD/F content was found in a particle size <0.21 mm, that is, 28.4, 16.1, 70.1 and 12.5 pg I-TEQ/g, respectively, with averaged 25.8 pg I-TEQ/g. Furthermore, it was also found that PCDD/F content increased with decreasing particle size. 3. For PCDD/F congener profiles in bottom ashes of the four selected MSWIs, OCDD and 1,2,3,4,6,7,8-HpCDD in rank are the most abundant congeners in PCDDs, while OCDF and 1,2,3,4,6,7,8-HpCDF are the most abundant congeners in PCDFs. 4. Hg and Cd contents increased with decreasing particle size of bottom ash from the four selected MSWIs. Most Fe concentrated in the middle particle size. The Pb, As, and Mn size distributions of the bottom ashes were all bimodal size distribution, indicating that the above metals concentrated in both fine and coarse particles. 5. The Pb, Hg, Cd, As and Fe contents in the bottom ashes of the four selected MSWIs were between 842~3160, 0.0394~0.338, 1.79~11.4, 5.65~16.5 and 41000~120000 mg/kg, respectively. The wide ranges of the metals content were due to the differences in the physical and chemical composition of the wastes among the four selected MSWIs. 6. The total PCDD/F emission factors were Stack (8.47 μg/ton-waste; 0.454 μg I-TEQ/ton-waste), BR (58.2 μg/ton-waste; 3.54 μg I-TEQ/ton-waste), SH (4.40 μg/ton-waste; 0.306 μg I-TEQ/ton-waste), EC (961 μg/ton-waste; 31.9 μg I-TEQ/ton-waste), SDA (100 μg/ton-waste; 3.66 μg I-TEQ/ton-waste), FF (1870 μg/ton-waste; 160 μg I-TEQ/ton-waste) and FAP (3610 μg/ton-waste; 323 μg I-TEQ/ton-waste), respectively. PCDD/Fs might be formed (674 μg/ton-waste; 128 μg I-TEQ/ton-waste) during transportation process. 7. The total emission amount of PCDD/Fs from Stack, BR, SH, EC, SDA, FF and generation were 0.00484, 0.0377, 0.00326, 0.340, 0.0390, 1.70 and 1.36 g I-TEQ/week. Besides, total emission amount of PCDD/Fs from the stacks in this MSWI was 0.596 (=0.00484×(52×2.35+1)) g I-TEQ/week with considering the start-up operations. Therefore, mass distribution ratios of PCDD/Fs in g I-TEQ/week from Stack, SH, EC, SDA, FF, generation and BR in star-up operations were 14.6%, 0.1%, 8.3%, 1.0%, 41.7%, 33.4% and 0.9%, respectively. The main PCDD/F source in the MSWI was from fly ash (~85%) although emission during start-up process was 2.35 times larger than that of a whole year’s normal operations. The above results indicated that main PCDD/F source in the MSWI was from fly ash. However, the fly ash is easily controlled and PCDD/Fs emitted from stack flue gases will be difficult to be handled. Therefore, we should pay more attention on PCDD/Fs emission from flue gases especially from start-up process.

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TE, LO MING, i 羅明德. "Assess PCDD/Fs Transfer in the Environmental Medium by Fugacity Model". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/35089849284783410246.

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碩士
國立屏東科技大學
環境工程與科學系
94
Following the development of civilization, the releases of man-made chemicals to the environment are increased day by day. Many among these substances are toxics. The common monitoring and modeling methods were used to evaluate fates of these compounds and their concentrations in the various parts of environment. Although the actual concentrations could be monitored through field sampling, it was costly and labor-intensive. As to the modeling, different models need to be used in order to account for chemical releases to different media. In addition, the modelers require highly specific knowledge and large amount of meteorology and hydrology data. On the other hand, the multi-media Fugacity model showed its simplicity and good functionality for determining chemical fates in multimedia transport, air, water, soil and others. It could predict the equilibrium concentrations of chemicals in various media compartment, justify the needs for further sampling, analysis and assessment, and further reduce the labor and cost for risk assessment. In order to evaluate the ability of the Fugacity model for simplifying the risk assessment, this study selected a MSWI. Using the data from the permit applications, this study modeled the fates of various pollutants by the Fugacity model and further explored the feasibility of simplify the process of risk assessment. This study would focus on 17 congeners. After collecting the emission data from the permit applications, this study further analyzed by USEPA FIRE databank to generate the emission rate and amount of pollutants. After further modeling efforts by Fugacity simulation, these results were compared with the monitoring data and were used for risk assessment. The estimated total PCDD/Fs concentration were 7.59E-06 ng/Nm3 for air, 5.49E-06 ng/L for water, 6.84E-04 ng/g for soil and4.86E-04 ng/g for sediment. The model predictions were lower than monitoring data less one order. It conjectured that sources contribution and modeling bulk dimention. Mass fluxes between the compartments were calculated. The results show that main part of PCDD/Fs from the stack emission fall down to soil mainly, minor part moves to sediment compartment, then others medium. From the model estimates, major mass fluxes coming from emission source were shown to go to the soil and water through wet/dry deposition, then go to degradation mainly in the soil(99.5~89.2%) and sediment(10.2~0.4﹪). The results of this study indicated that the Fugacity model is obvious easier, simpler, more versatile, and faster mean. It can save labor and money. Therefore, the Fugacity model can be used as the screen tool in risk assessment or exposure potential in order to examine the fates of certain chemicals after their releases to the environment. It can also be used in the environmental impact assessment and quality management to justify the emission control of chemicals.

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Bai, Shih-Ting, i 白士庭. "Characterization of PCDD/Fs and dl-PCBs Emitted from Woodchip Boilers". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/68990617957898043589.

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碩士
國立中央大學
環境工程研究所
105
This study characterizes the formation and emission of PCDD/Fs and dl-PCBs in two woodchips boilers during different operating periods. Two woodchips boilers (referred to as Plant A and B) investigated in this study are located in northern Taiwan. The sampling program of Plant A was conducted during different operating stages, including start-up, normal operation and shut-down periods. The results indicate that PCDD/F and dl-PCB concentrations (588.2 ng/Nm3) at APCDs inlet during the start-up period are much higher than those measured during normal operation and shut-down periods due to unstable combustion conditions. Concentrations of PCDD/F and dl-PCB (41.05 ng/Nm3) measured at APCDs inlet during the shut-down period were even lower than that measured during the normal operating period. It is due to the lack of carbon and chlorine sources since woodchip was not fed into the boiler during the shut-down period. The Plant B was investigated under three operating conditions, including full feed loading with injection of activated carbon, full feed loading without injection of activated carbon and half feed loading with injection of activated carbon. PCDD/Fs and dl-PCBs concentrations (113.6 ng/Nm3) measured at APCDs inlet during the half feed loading are lower than those measured during the full feed loading (139.4 ng/Nm3) due to the reduction of input woodchips. The removal efficiences of gas-phase PCDD/Fs and dl-PCBs achieved with ACI+BF are 95.60% and 92.05%, respectively, which are higher compared to the case without injection of activated carbon (85.74% and 79.76%, respectively). It demonstrates that gas-phase PCDD/Fs and dl-PCBs emissions can be effectively reduced by activated carbon injection. Durig full feed loading with the injection of activated carbon, PCDD/F and dl-PCB concentrations at APCDs inlet of the Plant A are significantly higher than those measured in the Plant B, due to the lower combustion temperature (500-850 oC) compared with Plant B (850-925 oC). Combustion condition remarkably affects PCDD/F and dl-PCB formation within the woodchip combustion process. The TEQ concentration of PCDD/Fs measured at the stack of the Plant A during different operating stages are significantly higher than the emission limit, while those of Plant B are lower than the regulation limit (0.5 ng I-TEQ/Nm3). For both Plants A and B, solid-phase PCDD/Fs dominate at APCDs inlet during different operating conditions because combustion of woodchips generates high concentration particulate matter. Different operating stages of woodchips combustion do not affect distributions of PCDD/F congeners significantly. Major PCDD/F congeners at APCDs inlet of Plants A and B during different periods include 1,2,3,4,6,7,8-HpCDF, 1,2,3,4,6,7,8-HpCDD and OCDD. The composition of feeding materials and different operating conditions affect the distributions of dl-PCB congeners. Concentrations of dioxin (PCDD/Fs+dl-PCBs) in the BF ash of Plants A and B during full feed loading with injection of activated carbon are measured 979.2 and 406.2 ng/g. Removal efficiencies of PCDD/Fs and dl-PCBs of the Plant A are 95.56% and 88.63%, respectively, while those of the Plant B are 99.29% and 94.94%. PCDD/Fs and PCBs emission factors of Plant A are 17.24 and 1.120 μg WHO-TEQ/ton, respectively. For the Plant B, the emission factors of PCDD/Fs and PCBs are 1.520 and 0.1400 μg WHO-TEQ/ton, respectively.

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張庭睿. "Inhibition on Formation of PCDD/Fs in Fly Ashes of Incinerators". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/70212165780066569976.

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Chang, Chia-chia, i 張家嘉. "Characteristics of PCDD/F Emissions from Nonferrous Secondary Metal Smelting Industries". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/52994620936537946573.

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碩士
國立中央大學
環境工程研究所碩士在職專班
99
Dioxin is one of the most toxic persistent organic pollutants (POPs). In recent years, many countries are investigating the concentrations and distributions of dioxin in the stack gas and wastes from nonferrous secondary metal smelting industries to understand its generation and distribution. With the above-mentioned information, they are able to make suggestions for the source reduction and process modification. This study aims to compare the characteristics of dioxin generation from secondary copper smelting industry with three different feedstock compositions, which are primarily composed of copper, copper scrap recycling in plant and copper scrap recycling plant outside. As for aluminum secondary metal smelting industry, the characteristics of dioxin formation with three feedstock compositions that mainly consists of aluminum cutting material, tire aluminum ring and aluminum scraps are investigated. Even if the feedstock ratios are different, the results indicate that the contributions of dioxin congeners in stack gas and waste are similar. Moreover, the international toxicity equivalency concentration contributed by the same species are close as well. 10-20% of the international toxicity equivalency concentration is from PCDD while the rest is attributed to PCDF. PCDF is the dominating species. The dominating species for PCDD and PCDF are 12378-PeCDDand 2378-TCDD, and 23478-PeCDF and 234678-HxCDF, respectively. Furthermore, the dioxin concentration from copper secondary metal smelting industry (2.92~12.4 ng I-TEQ/Nm3) is significantly higher than that from aluminum secondary metal smelting industry (0.14~0.25 ng I-TEQ/Nm3). For both industries, dioxin tends to accumulate on the particle surface because of its physical and chemical properties. Therefore, dioxin is mostly distributed in solid phase. While the particles in stack gas are collected by the air pollution control equipment, the dioxin concentration in solid phase decreases as well (0.13~0.40 ng I-TEQ/Nm3) and it meets the emission standard (1.0 ng I-TEQ/Nm3). In contrast, PCDD/F concentrations based on toxic equivalent in fly ashes ranged from 0.466 to 28.8 ng I-TEQ/g. That is significantly higher than the standard for the hazardous industrial waste regulated by Taiwan EPA. Hence, how to properly dispose of highly dioxin contaminated fly ash remains a great concern.

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WINNER i 江俊穎. "Effects of Differential Fuels on the Distribution Characteristics of PCDD/Fs". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/63030464882105518048.

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碩士
大葉大學
環境工程學系碩士在職專班
95
The effects of diifferential fuels on the distribution characteristics of PCDD/Fs was explored in this study for investigating the municipal solid wastes (MSW) incinerator, industrial wastes incinerator, and burn-wood boiler. The information was obtained from the measurement report submit to the environmental protection bureau. Before comparing the concentration (corrected to 11% oxygen concentration) and the species of dioxins, the accuracy for the sampliy method and the reasonableness of the data were investigating carefully. The results in this study indicated that (1) Normal garbage will make 2, 3, 4, 7, 8-PCDF and then 2,3,4,6,7,8-HCDF and 1, 2,3,6,7,8-HCDD. (2) The industrial garbage will make 2,3,4,7,8-PCDF and then 2,3,4,6,7,8-HCDF and 1,2,3,6,7,8-HCDF. (3) The burn-wood boiler will make 2,3,4,7,8-PCDF and then 1,2,3,7,8- PCDD and 2,3,7,8-TCDD. Therefore, the concentrations of 2, 3, 4, 7, 8-PCDF Dioxins chemical composition will be the mainly production from three different types of incinerators.

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Cater, Shari. "Historical trends of polychlorinated dibenzo-p-dioxins and dibenzofurans in fish and sediment associated with two bleached kraft pulp mills in northern Ontario". Thesis, 2013. http://hdl.handle.net/10012/8078.

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In the early 1990s polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) contamination of fish was widely associated with bleached kraft pulp mills. Regulations were put into place in Canada and elsewhere to reduce or eliminate the presence of these chemicals in pulp mill effluents. The industry quickly introduced treatment and process changes such as elemental (ECF) and total chlorine free (TCF) bleaching, which resulted in dramatically reduced PCDD/F concentrations in pulp mill effluents. However, PCDD/Fs may remain a concern for the receiving environment near bleached kraft pulp mills due to their tendency to persist in sediments and bioaccumulate in aquatic biota. Several studies conducted in the early 1990s reported significantly elevated levels of PCDD/Fs in white sucker (Catostomus commersoni) exposed to bleached kraft mill effluent (BKME). Particularly high concentrations were observed in the receiving environment of two mills in northern Ontario. The first mill, located in the town of Terrace Bay, discharges effluent into Jackfish Bay, Lake Superior. The second mill is located in Smooth Rock Falls, Ontario and discharges effluent into the Mattagami River where effects have been observed in fish collected downstream of the pulp mill. Over time, both mills have undergone a number of process upgrades, including a transition to 100% chlorine dioxide (ClO2) substitution. In 2006 the Tembec Smooth Rock Falls Pulp and Paper Mill closed permanently, while the mill in Terrace Bay has gone through a number of temporary shutdowns and is currently in the process of transitioning to a dissolving pulp process. Temporal changes in PCDD/F contamination was examined in white sucker historically exposed to BKME in Jackfish Bay and the Mattagami River, following mill process changes and closures. Historical data was summarized from studies conducted in the 1990s and analyzed along with liver tissue of male white sucker collected from each location in 2011 and 2012. The body burden of each fish was analysed using Toxic Equivalency (TEQ) calculations to account for concentration and relative toxicity of 2,3,7,8??? substituted PCDD/F congeners. At Jackfish Bay, concentrations of PCDD/Fs in surface sediment and dated sediment cores were used to document the spatial and temporal pattern of PCDD/F contamination in relation to historical process upgrades and operational changes at the mill. PCDD/Fs measured in white sucker liver samples collected from Jackfish Bay during gonadal recrudescence in the fall illustrate a decrease in mean TEQ from 74.2 ?? 20.9 pg???g-1 in 1991 to 3.34 ?? 2.05 pg???g-1 in 2012. These values were slightly elevated compared to the remote reference location at Mountain Bay, Lake Superior, which exhibited a mean TEQ of 1.88 ?? 0.45 pg???g-1 and 1.06 ?? 0.69 pg???g-1 in white sucker collected in fall 2011 and 2012, respectively. Although below consumption guidelines, trace levels of PCDD/Fs persist in fish collected from Jackfish Bay and these concentrations are suspected to reflect sediment contamination in Moberly Bay (part of Jackfish Bay). A unique PCDD/F contaminant profile, dominated by 2,3,7,8??? tetrachlorodibenzo???p???dioxin (TCDD) and dibenzofuran (TCDF), was observed in white sucker and sediment collected from Jackfish Bay. Analysis of surface sediment collected throughout Jackfish Bay revealed elevated PCDD/F concentrations, compared to reference areas in Lake Superior. TEQ values measured in surface sediment from the depositional areas of Moberly Bay exceeded the Canadian Council of Ministers of the Environment (CCME) guidelines. In 1991 PCDD/F contamination, reported as mean TEQ, of white sucker collected downstream of the pulp mill outfall in Smooth Rock Falls reached levels of 111 ?? 86.2 pg???g-1. At the time, the mill utilized molecular chlorine (Cl2) in the bleaching sequence and employed primary effluent treatment. A dramatic decline was observed in PCDD/F concentrations of fish collected in 1993 and 1995, corresponding to implementation of 100% ClO2 substitution in the bleaching process. PCDD/F contamination in white sucker collected from the Mattagami River in 2011 and 2012 were similar upstream (0.53???1.49 pg TEQ???g-1) and downstream (0.75???2.87 pg TEQ???g-1) of the historical pulp mill outfall at Smooth Rock Falls, suggesting a return to background condition following the 2006 mill closure. Levels of 2,3,7,8???TCDD and 2,3,7,8???TCDF in liver tissue of fish collected downstream declined drastically compared to concentrations measured in 1991. The PCDD/F congener profile observed in white sucker downstream in 2011 and 2012 was more similar to fish collected from the reference site upstream than exposed fish collected in 1991. No sediment depositional areas suitable for taking a core sample were found on the river downstream of Smooth Rock Falls due to the nature of the system. This study supports the conclusion that particulate (POM) and dissolved organic matter (DOM) from continuous inputs of effluent were likely the primary source of PCDD/Fs to fish in these receiving environments, with only a small contribution from surface sediment. Results indicate a decreasing trend in PCDD/F contamination of white sucker historically exposed to bleached kraft pulp mill effluent in the receiving environments of Jackfish Bay and the Mattagami River, consistent with mill process upgrades to eliminate the use of elemental chlorine from the bleaching sequence. Current levels of PCDD/Fs measured in white sucker collected from these locations suggest a return to background condition.

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Chen, Hsiu-Ling, i 陳秀玲. "Effect of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) exposure on Taiwanese: Investigation on environmental sources of PCDD/Fs and risk assessment on exposed population". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/03014672452932361590.

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博士
國立成功大學
基礎醫學研究所
92
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) is a group of toxic substances generated unintentionally as by-products from human activities such as combustion, paper processing, and pesticide production. Most PCDD/Fs are resistant to environmental and biological degradation, and dispersed into environment through water, soil, foods, and the atmosphere. It has been estimated that more than 95% of serum PCDD/Fs are attributable to the consumption of various food groups. The aim of this study, therefore, was to compare the serum PCDD/Fs patterns of residents living in the vicinity of functioning incinerators and to examine how dietary patterns or air exposure were associated with their serum PCDD/F concentrations. In addition, this study intended to estimate the average daily intake of dioxin-like compounds and to examine the interactive influence of CYP1A1 genotypes and PCDD/Fs exposure on health influences. 　　One thousand seven hundred and twelve volunteers living near incinerators were recruited from 2000 to 2003. All selected subjects were between 18-65 years old and proportionally chosen from each age group based on population distribution. In addition, they had to have lived within a 5-km radius of the incinerator for at least 5 years. All subjects needed to complete health and dietary questionnaires, 13 blood biochemistry test, analysis of genetic polymorphism at CYP1A1/Msp 1 and Nco 1, and serum PCDD/Fs analysis. 　　Average serum PCDD/Fs levels were 19.7 pg WHO-TEQ/g lipid. Higher serum PCDD/F levels were found in older than in younger subjects, and higher PCDD/F concentrations were found in females than in males. In addition, nonsmokers and passive smokers showed higher levels of PCDD/Fs than active smokers. 　　The serum PCDD/Fs levels of people were not associated to the ambient exposure dose or operated period of incinerator. However, distributions of 17 serum PCDD/Fs congeners were affected by different ambient exposure dose. 　　For dietary analysis, serum PCDD/Fs level was significantly higher in non-vegetarian than vegetarian, and higher in subjects responding they often eat local food than those responding never. The result also presented the distribution of serum PCDD/Fs levels in different groups. The highest serum PCDD/Fs level was observed in a fishing port (24.1 pg WHO-TEQ/g lipid), the following is in industrial area (21.8 pg WHO-TEQ/g lipid), in rural area (17.9), in urban area (17.0), and the lowest is in urban and rural area (16.5). The significant positive multivariate-adjusted association was found between serum PCDD/F levels and sea fish intake and negative in egg and tofu intake. We might suggest that if people took more soybean protein such as tofu, then lower serum PCDD/Fs levels might be expected in relation to less body fat content and induction of metabolic enzymes such as quinone reductase and UDP-GST. 　　Significantly elevated levels of glucose and blood urea nitrogen were found in those from low to high serum PCDD/Fs levels, and PCDD/Fs levels were found to be positively associated with hypertension and diabetes even after adjusting for age, sex, BMI and smoking status. In addition, the results reported here also suggest that the GPT levels may be modified by interaction of CYP1A1/Msp 1 genotype and dioxin exposure levels after adjustment. 　　The estimated average daily intake of dioxins was 0.393 pg WHO-TEQ/kg body weight/day. Sea fish presented the highest concentration of PCDD/Fs and the followed was fresh water fish and beef. The ambient exposure contributed 2.56% of daily intake and dietary intake contributed 97.4%. However, the vegetables were still not been included for estimating the dietary intake, and it might be under-estimated. 　　Further studies are needed to characterize the variation of other related genes to verify the correlation between serum PCDD/Fs levels and other health effects. Moreover, it will be necessary to set a strategy in foodstuff to prevent the excess PCDD/Fs accumulation from the food planted or grown originally near a probable contaminant source.

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