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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Carex establishment on reclaimed oil sands landscapes : a case study at Suncor Energy Inc.

Marlowe, Patricia Ann 14 March 2011 (has links)
Reclaimed oil sands landscapes are perceived to be low in plant diversity compared with naturally occurring plant communities. Approximately 66 Carex species inhabit the oil sand region. This thesis is unique and represents the first large scale study of Carex establishment on reclaimed oil sands landscapes. Research compared diversity and habitat variables between natural ecosystems and reclaimed landscapes, and examined the colonization mechanism for Carex establishment on reclaimed landscapes (i.e., ingress from adjacent natural ecosystems or emergence from the soil seed bank). Low positive associations between the presence of Carex in natural and reclaimed landscapes, and the presence of species on reclaimed landscapes not accounted for in either the forest or edge plots, suggests Carex established from the soil seed bank and less so from natural ingress. Carex share the same seed dispersal mechanisms as many plants, so the implications may apply to a broader range of plant species.
152

La ferme du Bas-de-la-Baie, 1673-1759 : contribution zooarchéologique à l'étude des sites ruraux

Bossé, Éliane 03 1900 (has links)
Ce mémoire présente les résultats d'une recherche zooarchéologique portant sur deux occupations d'un site du début de la colonisation à Baie-Saint-Paul (XVIIe-XVIIIe siècle). L'analyse de leurs assemblages fauniques, totalisant 1175 restes osseux, a démontré le caractère diamétralement opposé des deux occupations. Le site d'habitation des goudronniers a révélé une exploitation des ressources sauvages visant à suppléer un élevage déficient et fournir un revenu d'appoint par le commerce des fourrures. Pour sa part, le site de la ferme établie par le Séminaire de Québec a révélé une alimentation basée sur les produits de l'élevage, mais supplée par la chasse de gibier disponible dans les environs immédiats du site. La différence d'exploitation faunique soulignée par l'étude zooarchéologique du site de la ferme du Bas-de-la-Baie a également permis de confirmer le rôle central de l'élevage pour les sites ruraux de la vallée laurentienne tout en soulignant leur variabilité, visible au sein de l'élevage et dans l'apport supplémentaire fourni par la chasse et la pêche. / This Master's thesis presents the results of a zooarchaeological study based on two occupations of a single site dating to the beginning of the colonization of Baie-Saint-Paul (17th-18th centuries). An analysis of the faunal assemblage, a total of 1175 animal bones, has shown the opposite characters of the occupations. The "tar makers'" habitation site reveals the exploitation of wild ressources to make up for deficient animal rearing, as well as the skinning of wild game to provide a supplementary income through the fur trade. The farm established by the Séminaire de Québec reveals an alimentation based on farm produce, augmented by the hunting of wild species from the immediate environment. The zooarchaeological study of the Bas-de-la-Baie farm site also confirms the central role of breeding for rural sites in the St. Lawrence Valley, while underlining their diversity, in which farming, hunting and fishin played complementary roles.
153

Evaluation of thermal desorption as an alternative technique for the measurement of coal tar pitch volatiles / Cornelius Johannes van der Merwe

Van der Merwe, Cornelius Johannes January 2011 (has links)
Motivation: The accurate and reliable measurement of the concentration of coal tar pitch volatiles (CTPVs) in ambient air has proved to be a challenge for occupational hygienists. The challenge must however be confronted due to, amongst others, the carcinogenic properties of some poly–aromatic hydrocarbons (PAHs) contained in CTPVs. Aim: To determine the feasibility of a thermal desorption (TD) technique based method as an alternative method to be used for the measurement of the concentration of CTPVs in ambient air by assessing it along criteria such as ease of use, cost, accuracy and precision by comparing it to NIOSH’s Method 5515 and OSHA’s Method 58 and to determine the level of exposure to CTPVs on the anode paste floor of an electric furnace, used for the smelting of platinum group metals (PGMs) concentrate. Methodology: To satisfy the research objective, two accepted methods the National Institute of Occupational Safety and Health’s (NIOSH) method 5515 and the Occupational Safety and Health Administration’s (OSHA) method 58 were used for the measurement of the concentration of CTPVs with a TD technique based method used as a third, alternative method. All three methods were used concurrently to measure the concentration of CTPVs in ambient air, at the anode paste floor of a platinum group metals (PGMs) concentrate smelter. Results and conclusions: The NIOSH method proved to be the most precise method while the TD technique based method proved to be the most accurate. The TD technique based method proved to measure the widest range of individual CTPVs and were able to measure the highest concentration of Benzo(a)pyrene, an individual CTPV that is classified as a Group 1 (carcinogenic to humans) chemical substance by the International Agency for Research on Cancer (IARC). The OSHA method measured on average almost four times less total CTPVs than either the NIOSH or the TD technique based method and failed to readily measure individual CTPVs with a molecular weight lower than that of Phenanthrene. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2012.
154

Evaluation of thermal desorption as an alternative technique for the measurement of coal tar pitch volatiles / Cornelius Johannes van der Merwe

Van der Merwe, Cornelius Johannes January 2011 (has links)
Motivation: The accurate and reliable measurement of the concentration of coal tar pitch volatiles (CTPVs) in ambient air has proved to be a challenge for occupational hygienists. The challenge must however be confronted due to, amongst others, the carcinogenic properties of some poly–aromatic hydrocarbons (PAHs) contained in CTPVs. Aim: To determine the feasibility of a thermal desorption (TD) technique based method as an alternative method to be used for the measurement of the concentration of CTPVs in ambient air by assessing it along criteria such as ease of use, cost, accuracy and precision by comparing it to NIOSH’s Method 5515 and OSHA’s Method 58 and to determine the level of exposure to CTPVs on the anode paste floor of an electric furnace, used for the smelting of platinum group metals (PGMs) concentrate. Methodology: To satisfy the research objective, two accepted methods the National Institute of Occupational Safety and Health’s (NIOSH) method 5515 and the Occupational Safety and Health Administration’s (OSHA) method 58 were used for the measurement of the concentration of CTPVs with a TD technique based method used as a third, alternative method. All three methods were used concurrently to measure the concentration of CTPVs in ambient air, at the anode paste floor of a platinum group metals (PGMs) concentrate smelter. Results and conclusions: The NIOSH method proved to be the most precise method while the TD technique based method proved to be the most accurate. The TD technique based method proved to measure the widest range of individual CTPVs and were able to measure the highest concentration of Benzo(a)pyrene, an individual CTPV that is classified as a Group 1 (carcinogenic to humans) chemical substance by the International Agency for Research on Cancer (IARC). The OSHA method measured on average almost four times less total CTPVs than either the NIOSH or the TD technique based method and failed to readily measure individual CTPVs with a molecular weight lower than that of Phenanthrene. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2012.
155

Sustentabilidade da Estrategia Saúde da Família: o caso de um município baiano

Oliveira, Sydia Rosana de Araújo 03 September 2014 (has links)
Submitted by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2015-04-20T11:45:03Z No. of bitstreams: 1 Tese Final Sydia Rosana Oliveira. 2014.pdf: 2379286 bytes, checksum: 3dd23c2bacf00a5fd8d62a0c3c04e8fd (MD5) / Approved for entry into archive by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2015-04-20T13:26:40Z (GMT) No. of bitstreams: 1 Tese Final Sydia Rosana Oliveira. 2014.pdf: 2379286 bytes, checksum: 3dd23c2bacf00a5fd8d62a0c3c04e8fd (MD5) / Made available in DSpace on 2015-04-20T13:26:40Z (GMT). No. of bitstreams: 1 Tese Final Sydia Rosana Oliveira. 2014.pdf: 2379286 bytes, checksum: 3dd23c2bacf00a5fd8d62a0c3c04e8fd (MD5) / Esta tese tem como objetivo analisar a sustentabilidade da Estratégia Saúde da Família (ESF) em um município baiano, descrevendo a trajetória desta Intervenção, e identificando os fatores estratégicos que promoveram a sua sustentabilidade. Sustentabilidade refere-se à continuidade de uma Intervenção ao longo do tempo, fase do seu ciclo de vida pouco estudada no contexto nacional. Para esta análise, utilizou-se o referencial da Teoria do Ator-Rede (TAR), abordagem que trata objetos como parte de redes sociais heterogêneas, gerados pelas interações entre os entes da rede. Dados de análise documental e de entrevistas semiestruturadas com informantes-chave foram utilizados para construção de linha do tempo dos eventos que constituíam a trajetória da Intervenção. A unidade de análise foi o evento crítico, que compreende momentos de desestabilização na trajetória da Estratégia. Os resultados apontam seis eventos críticos, e um conjunto de fatores estratégicos que permitiram a reconfiguração da Intervenção e marcaram a sua manutenção ao longo do tempo. A análise evidenciou que estes fatores estratégicos identificados guardam correspondência com os já apresentados na literatura internacional e que a sustentabilidade de intervenções de Atenção Primária, em especial, da ESF é marcada pela influência destes fatores.
156

Caracterização e pirólise de arenitos asfálticos oriundos da Formação Pirambóia, Bacia do Paraná: avaliação da viabilidade para produção de óleo / Characterization and pyrolysis of asphaltic sandstones (tar sands) from Piramboia Formation, Paraná Basin: assessment of the feasibility for oil production

Iris Medeiros Júnior 11 March 2015 (has links)
Neste trabalho, algumas caracterizações químicas foram realizadas em arenitos asfálticos da região de Piracicaba-SP, Formação Piramboia da Bacia do Paraná, para verificar seu potencial de produção de óleo. Para isso, as amostras obtidas da região foram submetidas a avaliação por termogravimetria, teor de umidade, teor de cinzas, teor de material orgânico por extração, pirólise, análise elementar e fracionamento em coluna. Por TGA observou-se que a 500 C praticamente todo material orgânico presente sofreu pirólise. A extração colaborou para se obter a classificação das amostras quanto ao teor de material orgânico, apresentando entre 4 e 13%, sendo que pelos teores encontrados a amostra AM06 é considerada de alto potencial produtivo, as amostras AM05, AM08 e AM09 são de médio, as amostras AM01, AM02, AM03 e AM07 possuem baixo, mas ainda atrativo, e a AM04 não possui atratividade. Pela avaliação elementar, a relação H/C e O/C dos extratos evidenciaram que algumas amostras estão no processo final da diagênese e outras no início da catagênese, indicando que elas estão no processo inicial de maturação. A avaliação cromatográfica dos extratos revelou que houve perdas de óleo por intemperismo restando majoritariamente compostos de alto peso molecular. O fracionamento permitiu verificar que as amostras AM01, AM06 e AM09 possuem maior quantidade de hidrocarbonetos livres e as amostras AM06 e AM07 e AM09 apresentaram maior teor de óleo. O procedimento de pirólise evidenciou que as amostras AM01, AM05, AM06 e AM09 apresentam maior potencial de geração de óleo, sendo que a faixa encontrada de óleo pirolítico ficou entre 2 e 8%, e através de avaliação por CGAR e CGAR-EM observou-se que ela promove a liberação de quantidades consideráveis de substâncias mais leves do que quando comparados aos extratos obtidos diretamente nas amostras originais. Além de produzir uma série homóloga de hidrocarbonetos parafínicos e olefínicos. A comparação dos produtos de pirólise dos arenitos com os produtos de pirólise de um resíduo de vácuo por CGAR-EM permitiu observar que existe similaridade entre suas composições, onde o processo de pirólise do resíduo de vácuo gera uma série homóloga de hidrocarbonetos entre C10 a C32, similar aos produtos de pirólise da amostra AM09, porém com menor variedade de tipos de hidrocarbonetos. A pré-avaliação da co-pirólise dos arenitos com resíduos plásticos indicou que é possível aumentar a geração de líquidos, porém é necessário mais estudo para afirmações inequívocas. Com base nos resultados das avaliações realizadas podemos concluir que a região apresenta na sua maioria potencial interessante para produção de óleo utilizando pirólise / In this work, some chemical characterizations were held on tar sands in the region of Piracicaba-SP, the South American Piramboia Formation from Paraná basin, to check its oil production potential. For this purpose, samples obtained in the region have undergone through evaluation by thermogravimetry, moisture content, ash content, content of organic material using extraction, pyrolysis process, elemental analysis and fractionation on open chromatography column. By TGA was noted that 500 C almost all-organic material present suffered pyrolysis. Extraction procedure collaborated to achieve the classification of samples regarding the content of organic material, from 4 to 13%, and by levels found at the sample AM06 is considered of high productive potential, the samples AM05, AM08 and AM09 have medium potential, the samples AM01, AM02, AM03 and AM07 have low potential, but still attractive, and the AM04 does not have any potential. By evaluating the atomic relationship between H/C and O/C of the extracts was possible to build up the Van Krevelen diagram and see that some samples are in the final process of diagenesis and other early catagenesis, indicating that they are in the early maturation process. Chromatographic evaluation of the extracts revealed that there were losses of oil by weathering process because it remains mostly high molecular weight compounds on the rocks. The fractionation has shown that samples AM01, AM06 and AM09 have higher free hydrocarbon amount and samples AM06, AM07 and AM09 presented a higher level of oil content. The pyrolysis procedure showed that the samples AM01, AM05, AM06 and AM09 presented greater oil generation potential, pyrolytic oil released from 2 to 8%, and through their evaluation by HRGC and HRGC-MS it was observed that it promotes the release of significant quantities of substances that are lighter than related to the extracts obtained directly in the original samples. In addition, it also promotes a production of homologous series of paraffinic and olefinic hydrocarbons. Comparison of pyrolysis products of sandstones with pyrolysis products of vacuum residue by HRGC-MS allowed to observe that there is similarity between their compositions, which pyrolysis process of vacuum residue generates a homologous series of hydrocarbons between C10 the C32, similar to AM09s pyrolysis products, however with minor variety of types of hydrocarbons. The pre-evaluation of co-pyrolysis of sandstones with plastic waste has indicated that it is possible to increase the liquid generation, but more study is needed for clear statements. Based on the results of the evaluations it can be concluded that the region has an interesting potential for producing oil using pyrolysis process
157

Caracterização e pirólise de arenitos asfálticos oriundos da Formação Pirambóia, Bacia do Paraná: avaliação da viabilidade para produção de óleo / Characterization and pyrolysis of asphaltic sandstones (tar sands) from Piramboia Formation, Paraná Basin: assessment of the feasibility for oil production

Iris Medeiros Júnior 11 March 2015 (has links)
Neste trabalho, algumas caracterizações químicas foram realizadas em arenitos asfálticos da região de Piracicaba-SP, Formação Piramboia da Bacia do Paraná, para verificar seu potencial de produção de óleo. Para isso, as amostras obtidas da região foram submetidas a avaliação por termogravimetria, teor de umidade, teor de cinzas, teor de material orgânico por extração, pirólise, análise elementar e fracionamento em coluna. Por TGA observou-se que a 500 C praticamente todo material orgânico presente sofreu pirólise. A extração colaborou para se obter a classificação das amostras quanto ao teor de material orgânico, apresentando entre 4 e 13%, sendo que pelos teores encontrados a amostra AM06 é considerada de alto potencial produtivo, as amostras AM05, AM08 e AM09 são de médio, as amostras AM01, AM02, AM03 e AM07 possuem baixo, mas ainda atrativo, e a AM04 não possui atratividade. Pela avaliação elementar, a relação H/C e O/C dos extratos evidenciaram que algumas amostras estão no processo final da diagênese e outras no início da catagênese, indicando que elas estão no processo inicial de maturação. A avaliação cromatográfica dos extratos revelou que houve perdas de óleo por intemperismo restando majoritariamente compostos de alto peso molecular. O fracionamento permitiu verificar que as amostras AM01, AM06 e AM09 possuem maior quantidade de hidrocarbonetos livres e as amostras AM06 e AM07 e AM09 apresentaram maior teor de óleo. O procedimento de pirólise evidenciou que as amostras AM01, AM05, AM06 e AM09 apresentam maior potencial de geração de óleo, sendo que a faixa encontrada de óleo pirolítico ficou entre 2 e 8%, e através de avaliação por CGAR e CGAR-EM observou-se que ela promove a liberação de quantidades consideráveis de substâncias mais leves do que quando comparados aos extratos obtidos diretamente nas amostras originais. Além de produzir uma série homóloga de hidrocarbonetos parafínicos e olefínicos. A comparação dos produtos de pirólise dos arenitos com os produtos de pirólise de um resíduo de vácuo por CGAR-EM permitiu observar que existe similaridade entre suas composições, onde o processo de pirólise do resíduo de vácuo gera uma série homóloga de hidrocarbonetos entre C10 a C32, similar aos produtos de pirólise da amostra AM09, porém com menor variedade de tipos de hidrocarbonetos. A pré-avaliação da co-pirólise dos arenitos com resíduos plásticos indicou que é possível aumentar a geração de líquidos, porém é necessário mais estudo para afirmações inequívocas. Com base nos resultados das avaliações realizadas podemos concluir que a região apresenta na sua maioria potencial interessante para produção de óleo utilizando pirólise / In this work, some chemical characterizations were held on tar sands in the region of Piracicaba-SP, the South American Piramboia Formation from Paraná basin, to check its oil production potential. For this purpose, samples obtained in the region have undergone through evaluation by thermogravimetry, moisture content, ash content, content of organic material using extraction, pyrolysis process, elemental analysis and fractionation on open chromatography column. By TGA was noted that 500 C almost all-organic material present suffered pyrolysis. Extraction procedure collaborated to achieve the classification of samples regarding the content of organic material, from 4 to 13%, and by levels found at the sample AM06 is considered of high productive potential, the samples AM05, AM08 and AM09 have medium potential, the samples AM01, AM02, AM03 and AM07 have low potential, but still attractive, and the AM04 does not have any potential. By evaluating the atomic relationship between H/C and O/C of the extracts was possible to build up the Van Krevelen diagram and see that some samples are in the final process of diagenesis and other early catagenesis, indicating that they are in the early maturation process. Chromatographic evaluation of the extracts revealed that there were losses of oil by weathering process because it remains mostly high molecular weight compounds on the rocks. The fractionation has shown that samples AM01, AM06 and AM09 have higher free hydrocarbon amount and samples AM06, AM07 and AM09 presented a higher level of oil content. The pyrolysis procedure showed that the samples AM01, AM05, AM06 and AM09 presented greater oil generation potential, pyrolytic oil released from 2 to 8%, and through their evaluation by HRGC and HRGC-MS it was observed that it promotes the release of significant quantities of substances that are lighter than related to the extracts obtained directly in the original samples. In addition, it also promotes a production of homologous series of paraffinic and olefinic hydrocarbons. Comparison of pyrolysis products of sandstones with pyrolysis products of vacuum residue by HRGC-MS allowed to observe that there is similarity between their compositions, which pyrolysis process of vacuum residue generates a homologous series of hydrocarbons between C10 the C32, similar to AM09s pyrolysis products, however with minor variety of types of hydrocarbons. The pre-evaluation of co-pyrolysis of sandstones with plastic waste has indicated that it is possible to increase the liquid generation, but more study is needed for clear statements. Based on the results of the evaluations it can be concluded that the region has an interesting potential for producing oil using pyrolysis process
158

A matem?tica sob a ?tica do Tar?: Uma experi?ncia com a educa??o de jovens e adultos

Albuquerque, Regina L?cia Tarqu?nio de 15 April 2004 (has links)
Made available in DSpace on 2014-12-17T15:04:48Z (GMT). No. of bitstreams: 1 ReginaLTA.pdf: 1575029 bytes, checksum: b18b341ec6d8bcdd9d246dedf3404e75 (MD5) Previous issue date: 2004-04-15 / La recherche de la formation des citoyens critiques et participatifs, dans le travail p?dagogique avec les jeunes et les adultes, a besoin d un entra?nement p?dagogique qui va au del? de l attitude traditionnelle d'apprendre avec des m?thodes m?caniques et arbitraires qui, en insistant excessivement sur l image du professeur, donnent priorit? ? l'enseignement, au d?triment de l apprentissage. Dans ce sens, la pr?sente ?tude, cherchant la possibilit? de r?alisation d'un travail alternatif pour l'enseignement des Math?matiques, dans une perspective transdisciplinaire, dans le sens de d?velopper l apprentissage significatif des ?tudiants jeunes et adultes du Projet Croire, pr?sente les r?sultats d'une recherche-intervention qui a utilis? les lettres du tarot comme ressource didactique en salle de classe. On pr?tend, avec cela, montrer cet instrument comme facilit? d apprentissage de contenus des Math?matiques comme syst?mes de num?ration, nombres entiers et g?om?trie, en amenant les Math?matiques dans une perspective historique et culturelle et donnant un traitement global ? l'acte complexe d'apprendre. Dans ce travail, le jeune ?tudiant et l ?tudiant adulte est pris comme individu concret, prenant en consid?ration les aspects cognitifs et les aspects d attitude de son apprentissage, ce qui est favoris? par la nature des lettres du tarot et par la compr?hension adopt?e, des math?matiques comme syst?me symbolique / A busca da forma??o de cidad?os cr?ticos e participativos, no trabalho educativo com jovens e adultos, enseja uma pr?tica docente que v? al?m da postura tradicional de ensinar com m?todos mec?nicos e arbitr?rios, que, ao focarem excessivamente a figura do professor, priorizam o ensino, em detrimento da aprendizagem. Nessa dire??o, o presente estudo, ao procurar a possibilidade de realiza??o de um trabalho alternativo para o ensino de Matem?tica, numa perspectiva transdisciplinar, no sentido de desenvolver aprendizagem significativa de alunos jovens e adultos do Projeto Acreditar, apresenta os resultados de uma pesquisa-interven??o que utilizou as cartas de tar? como recurso did?tico em sala de aula. Pretende-se, com isso, mostrar tal instrumento como facilitador da aprendizagem de conte?dos da Matem?tica como sistemas de numera??o, n?meros inteiros e geometria, tomando a Matem?tica numa perspectiva hist?rico-cultural e dando um tratamento hol?stico ao complexo ato de aprender. Nesse trabalho, o aluno jovem e adulto ? tomado como indiv?duo concreto, levando-se em considera??o os aspectos cognitivos e atitudinais de seu aprender, o que ? favorecido pela natureza das cartas do tar? e pela compreens?o adotada, de matem?tica como sistema simb?lico
159

Reforma de gás de gaseificação por meio de tocha de plasma : ensaios preliminares / Reformation of gasification gas by plasma torch : preliminary results

Neves, Renato Cruz, 1987- 23 August 2018 (has links)
Orientador: Caio Glauco Sánchez / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-23T14:06:22Z (GMT). No. of bitstreams: 1 Neves_RenatoCruz_M.pdf: 25784234 bytes, checksum: ce1b9833db6f80c61b19cd8781d17a52 (MD5) Previous issue date: 2013 / Resumo: O desafio da tecnologia de reforma de gás de gaseificação é realizar a conversão de alcatrão e particulados em um gás, pois estes contaminantes podem trazer diversos problemas ao sistema de gaseificação como entupimento de filtros e corrosão. Dentre os equipamentos e métodos para a reforma do gás de gaseificação, encontra-se o plasma. Neste trabalho foi projetado, construído e ensaiado um sistema de reforma de gás de gaseificação proveniente de um reator de gaseificação utilizando a tocha de plasma. O sistema de reforma a plasma é constituído pela tocha de plasma inserida na garganta de um tubo convergente-divergente instalado na tubulação de saída do reator de gaseificação. A fonte de alimentação da tocha de plasma é o modelo Powermax1250 e a tocha é o modelo T80M, ambos da marca Hypertherm. A tocha de plasma utiliza nitrogênio como gás de trabalho, opera com pressão de 4; 0 bar no modo arco elétrico com corrente contínua, plasma térmico, não-transferido e alcança temperaturas superiores a 1673 K em distâncias menores que 30 mm. Na gaseificação foi utilizada a serragem de Peroba e Garapeira, fator de ar de 0; 22, velocidade de fluidização de 0,57 m.s-1 e utilizou-se 550 mm de altura do leito fixo de areia quartzosa. A coleta de alcatrão e particulado foi adaptada da norma CEN/BT/TF 143 ("Biomass gasification - Tar and particules in product gases - sampling and analysis"). Nas condições estudadas e analisadas deste trabalho, o valor obtido para a vazão mássica de alcatrão e material particulado foi de (5; 26+0; 58)10-3 g.s-1 para a gaseificação convencional enquanto que para a gaseificação utilizando a tecnologia da reforma de plasma foi de (3; 97+0; 14)10-3 g.s-1, que representou uma redução de 24; 52 % / Abstract: The technologic challenge on reformation of gasification gas is to convert tar and particulate matter into gas, because they can cause various problems on gasification system as corrosion and filters clogging. Among the equipment and methods for gasification gas reformation, it is used the plasma. In this work was designed, built and tested a system for gasification gas reformation from a gasification reactor using a plasma torch. The plasma system is formed by plasma torch inserted in the throat of a convergent-divergent tube installed in the outlet pipe of the gasification reactor. The power supply of the plasma torch is Powermax1250 and the model T80M plasma torch, both from Hypertherm brand. The plasma torch uses nitrogen as working gas, operates at a pressure of 4; 0 bar with arc current mode, thermal plasma, non-transferred and reaches temperatures above 1673 K in distances of less than 30 mm. In the gasification was used Peroba and Garapeira sawdust, air factor 0:22, fluidization velocity 0,57 m.s-1and 550 mm height fixed bed of quartz sand. The tar and particulate collection was adapted from CEN/BT/TF 143 (Biomass gasification - tar and particules in product gases - sampling and analysis). Under the conditions studied and analyzed in this work, the value obtained for the mass flow of tar and particulate material was (5; 26+0; 58)10-3 g.s-1 for conventional gasification while for using the reformation of gasification gas was de (3; 97+0; 14)10-3 g.s-1, which represented a reduction of 24:52 % / Mestrado / Termica e Fluidos / Mestre em Engenharia Mecânica
160

Accessing intangible technologies through experimental archaeology : a methodological analysis

Schenck, Tine January 2015 (has links)
This thesis concerns the relationship between research in experimental archaeology and the intangible of the past. Only a quarter of technological experiments in a sample of 100 studies addresses the intangible of technological practice, and this project sets out to explore if there are conceptual or practical obstacles for this low rate. The thesis begins with an in-depth examination of experimental archaeology and the criteria, paradigms and theories that determine its practice. Through this study, elements of the dichotomy positivism/postmodernism are uncovered and discussed. To resolve this dualism, a third paradigm – philosophical pragmatism – is introduced as an alternative. This conceptual debate represents Part I, and is subsequently collated into a methodological framework for the creation of a typified experiment. Part II consists of the experimental segment of this study, in search for practical obstacles for the exploration of the intangible. Through experimenting with Iron Age Bucket-shaped pots, Mesolithic faceted pebbles and Middle Palaeolithic birch bark tar production, different components of an experiment are highlighted for investigation. An element that comes forward as problematic is the relationship between experimental archaeologists and science ideals that is underscored by experimental tradition. Conclusively, the final discussion leaves the conceptual and practical barriers that may prevent archaeologists from studying the intangible aspects of technology overturned. In sum, this may enable experimental archaeologists to take a fuller view of their own practice and that of the people of the past.

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