Att följa ammonium i reningsverk är avgörande för att förbättra reningsprocessen och kontrollera flödet av föroreningar ut till ekosystemet. Jonselektiva elektroder (ion-selective electrodes, ISEs) är en lovande teknik inom området, där polymermembran baserade på nonactin är de mest studerade membranen för ammoniumsensorer. Membranet droppas tillsammans med ett jon-till-elektron transducerande material på ett elektrodsubstrat av grafit eller glasartat kol. Nonactin-baserade jonselektiva elektroder har typiskt en detektionsgräns inom storleksordningen 10-5 M, men uppvisar betydande kaliuminterferenser. Ett elektrodsystem baserat på grafitelektroder, inkluderande en ISE och en referenselektrod (RE), studerades i detta examensarbete. De jonselektiva elektroderna producerades genom att droppa jon-till-elektron trandsducerande funktionella flerväggiga kolnanotuber (functional multiwalled carbon nanotubes, f-MWCNTs) lösta i tetrahydrofuran (THF) och en membrancocktail innehållande polyvinylklorid (PVC), mjukgörare och nonactin löst i THF på grafitelektroder. Membranet täcktes sedan med en buffrad polyvinylalkohol (PVA) hydrogel med pH 7 och ett gas-permeabelt membran. Referenselektroderna producerades genom att droppa en membrancocktail av polyvinylbutyral (PVB) mättat med NaCl på grafitelektroder. Jonselektiva elektroder med f-MWCNTs som jon-till-elektron transducerande lager och ett PVC-baserat ammonium-selektivt membran med nonactin producerades framgångsrikt. Elektroderna hade en detektionsgräns i storleksordningen 10-5 M, vilket kan jämföras med tidigare artiklar publicerade inom området. Ytterligare producerades PVB-baserade referenselektroder mättade med NaCl framgångsrikt. Referenselektroderna uppvisade små variationer när koncentrationer av olika salt varierades. Arbetet visade att det gaspermeabla membranet Hyflon AD i kombination med en PVA hydrogel inte var lämplig i den föreslagna konfigurationen, då hålrum formades i torkningsprocessen av det gaspermeabla membranet och membranet delaminerade. Det föreslogs att beteendet kunde vara en konsekvens av inkompatibilitet mellan PVC och det gaspermeable membranet, till följd av deras skillnad i polaritet. / Monitoring ammonium in wastewater is vital to improve the treatment process and monitor the release of the pollutant into the ecosystem. Ion-selective electrodes (ISEs) is a promising technique in the area where the ISE is often based on a polymeric membrane containing the ionophore nonactin. The polymeric ion-selective membrane is drop-cast onto graphite or glassy carbon electrode substrates together with an ion-to-electron transducing layer. Nonactin-based ISEs typically demonstrate a limit of detection (LOD) in the range of 10-5 M, but exhibit significant potassium interferences. A solid-state system based on graphite electrodes, including an ISE and a reference electrode (RE), was investigated in this study. The ISEs were produced by drop-casting ion-to-electron transducing functional multi-walled carbon nanotubes (f-MWCNTs) dispersed in tetrahydrofuran (THF) and a membrane cocktail comprising poly(vinyl chloride) (PVC), plasticizer, and nonactin dispersed in THF onto graphite electrodes. The membrane was then covered with a buffered poly(vinyl alcohol) (PVA) hydrogel of pH 7 and a gas-permeable membrane (GPM). The solid-state RE was produced by drop-casting a poly(vinyl butyral) (PVB) membrane cocktail saturated with NaCl onto the graphite electrode.  ISEs using f-MWCNTs as ion-to-electron transducers and a PVC-based ammonium-sensitive membrane with nonactin were successfully produced. The electrodes exhibited LODs in the range of 10-5 M, which is comparable to previous articles published on the subject. Additionally, PVB-based solid-state REs saturated with NaCl were successfully produced. The reference electrodes exhibited minor influences when varying the concentrations of various salts. The study showed that the GPM Hyflon AD combined with a PVA hydrogel was not suitable in this configuration, as air voids were formed in the drying process, and the membrane was easily delaminated. It was suggested that this behavior could be a consequence of the incompatibility of PVC and the GPM due to their difference in polarity.

L’objet de cette thèse est d’étudier plusieurs modèles probabilistes reliant les marches aléatoires et les arbres aléatoires issus de processus de branchement critiques.Dans la première partie, nous nous intéressons au modèle de marche aléatoire à valeurs dans un réseau euclidien et indexée par un arbre de Galton–Watson critique conditionné par la taille. Sous certaines hypothèses sur la loi de reproduction critique et la loi de saut centrée, nous obtenons, dans toutes les dimensions, la vitesse de croissance asymptotique du nombre de points visités par cette marche, lorsque la taille de l’arbre tend vers l’infini. Ces résultats nous permettent aussi de décrire le comportement asymptotique du nombre de points visités par une marche aléatoire branchante, quand la taille de la population initiale tend vers l’infini. Nous traitons également en parallèle certains cas où la marche aléatoire possède une dérive constante non nulle.Dans la deuxième partie, nous nous concentrons sur les propriétés fractales de la mesure harmonique des grands arbres de Galton–Watson critiques. On comprend par mesure harmonique la distribution de sortie, hors d’une boule centrée à la racine de l’arbre, d’une marche aléatoire simple sur cet arbre. Lorsque la loi de reproduction critique appartient au domaine d’attraction d’une loi stable, nous prouvons que la masse de la mesure harmonique est asymptotiquement concentrée sur une partie de la frontière, cette partie ayant une taille négligeable par rapport à celle de la frontière. En supposant que la loi de reproduction critique a une variance finie, nous arrivons à évaluer la masse de la mesure harmonique portée par un sommet de la frontière choisi uniformément au hasard. / The aim of this Ph. D. thesis is to study several probabilistic models linking the random walks and the random trees arising from critical branching processes.In the first part, we consider the model of random walk taking values in a Euclidean lattice and indexed by a critical Galton–Watson tree conditioned by the total progeny. Under some assumptions on the critical offspring distribution and the centered jump distribution, we obtain, in all dimensions, the asymptotic growth rate of the range of this random walk, when the size of the tree tends to infinity. These results also allow us to describe the asymptotic behavior of the range of a branching random walk, when the size of the initial population goes to infinity. In parallel, we treat likewise some cases where the random walk has a non-zero constant drift.In the second part, we focus on the fractal properties of the harmonic measure on large critical Galton–Watson trees. By harmonic measure, we mean the exit distribution from a ball centered at the root of the tree by simple random walk on this tree. If the critical offspring distribution is in the domain of attraction of a stable distribution, we prove that the mass of the harmonic measure is asymptotically concentrated on a boundary subset of negligible size with respect to that of the boundary. Assuming that the critical offspring distribution has a finite variance, we are able to calculate the mass of the harmonic measure carried by a random vertex uniformly chosen from the boundary.

Cam phasers allow improvements to the efficiency and emissions of internal combustion engines. The usage of hydraulic vane type cam phasers for heavy-duty applications have shown problems with oscillations during testing at Scania CV. To investigate the root cause of the oscillations a detailed 1-d simulation model has been created. The 1-d simulation model was calibrated and compared against measurements of a cam phaser system mounted on a physical engine. The 1-d simulation model of the cam phaser system was shown to be able to reproduce the oscillatory behavior seen in engine tests. But there are some concerns regarding the model's reliability, due to its dependence on the integration time step. It was determined that free air in the phaser chambers is causing the excessive oscillations. The source of the free air present in physical phasers are not yet fully understood, but the movement of the phaser control valve, opening and closing of the phaser chamber vents, in conjunction with motion of the phase oscillations has a significant effect on the phaser's chamber pressure, resulting in reduce pressures. The reduced pressures result in air being sucked in to the phaser, form both the oil control valve vent and external chamber leakages. Another potential sources of free air is dissolved air in the oil supply being released due to low pressures from oil pressure fluctuations. A potential solution to increase the stability of the phaser is to reduce the sources of air, by having an oil accumulator at the vent, limiting leakage, having a high and steady oil supply pressure, modifying the oil control valve ports to have a more gradual initial opening area and controlling the oil control valve appropriately. How to implement these implementations and evaluate them are left as future work. Potential improvements to get rid of the 1-d simulation model's dependence on the time step, increasing the model's reliability, are discussed, but not tested.

No description available.

Ìsìnrú na ní bawo ohun pàtàkì na ise ìtenumó ni Brasili ati ìbi: "ki banújé ní fun àwon ki jadekúrò Instituto Metodista Porto Alegre (IPA-RS) àwon ise ìtenumó?" Èrò: yé, mó, túka ìwé ré ati/tabi banújé fun àwon jadekúrò ilá ìweé àgbá ni Brasili ki tó si Centro Ecumênico de Cultura Negra (CECUNE). Kan ekeji ibéèrè àwárì: mò nípa ikó àwon egúngun Afrika; kó bawo bi fifún àwon ohun lâárín èda ènià, arãlé ati egbé; mò, ònà àwon já ogun aráye Dudu gaúcho ati Brasili; túka àwon ònà ise wonyi ni ilê-ayé, ni Brasili ati Àwon Ìlú Fi Kún. Ekó àwon ohun – ìwádi ìrí – síbí àwon ohun nípa àwon ibéèrè, ìbi, pàdé àwon èniyàn ki jadekúrò, ati, túka àwon ìwé àwon ibi iwadí. Ibéèrè pèlú àwon olùkó The John Lewis Warfield Center for African and African Americen Studies at The University of Texas at Austin – USA ati túka ida sílè àwon ìwé ìlú eyi nípa ibéèrè. Àwon ìdáhùn: bá àwon asa ibi ojõjó ti dé ikoja Afrika ki kòsílè àdáwó ré nínú awa; nínú àwon àkókò àwon erú, àwon ja ogun quilombolas rú jade àwon ni/fun òmìnirà àwon ko ìbásededé – ni ìtóbi ati àwon àkója – ni ekó ati ni ojá ise ati, ni àwon onírúurú ni àwon ibi egbé. Àwon ìdáhùn: àwon ibéèrè èdá ènià-arãlé- egbé ni eta àwon ohun pàtàkì fun àwon ise ìtenumó fun àwon jadekúrò: èhin-òla isé; èhin-òla ebí ati ara; àlá da; èda titun ènia; titun àsìkò; pó si ife pàápàá; ìwé ìhòhìn àwon ohun egbé; pó si ìdàpò ati ìsúná ati ayé. / A tese tem o ponto central nas Ações Afirmativas na sociedade brasileira e problematiza: "Que sentidos têm para os egressos do Instituto Metodista Porto Alegre (IPA-RS) as Ações Afirmativas?" Seu objetivo foi entender, compreender, analisar o papel dessas ações e/ou o sentido que tem para os egressos dessa Instituição de Ensino Superior privada, no Brasil, conveniada com o Centro Ecumênico de Cultura Negra (CECUNE). De forma secundária, ela objetivava conhecer, pelo estudo sistemático, a ancestralidade africana; aproximar as relações entre raça/etnia e classe social; compreender o caminho/processo das lutas do povo negro afro-gaúcho e brasileiro; analisar os caminhos dessas ações no mundo, especificamente no Brasil e nos Estados Unidos. Foi feito um estudo de caso – de natureza qualitativa – mediante coleta de dados por meio de questionários, entrevistas, encontro de egressos e análise de documentos dos locais da pesquisa. Foram entrevistados professores do The John Lewis Warfield Center for African and African American Studies at The University of Texas at Austin – USA e analisada a produção bibliográfica desse país sobre a temática. Como resultados, foram descobertos costumes locais cotidianos oriundos do passado africano que deixaram suas contribuições em nossa sociedade; nos tempos da escravidão, lutas quilombolas emergiram na/para abolição das desigualdades. Os conceitos das ações afirmativas se diferenciam – em amplitude e metas – na educação, no mercado de trabalho e na diversidade do convívio em espaços sociais. Concluiu-se que as relações raça-etnia-classe formam o tripé onde se destacam como sentidos da ação afirmativa para os egressos: futuro profissional; futuro familiar e pessoal; realização de um sonho; possibilidade de reconstrução da identidade; oportunidade única; elevação da autoestima; retratação cultural; avanço socioeconômico e perspectiva de vida. / This dissertation has the central concern with the affirmative actions in the Brazilian society and problematizes: "What meanings do the affirmative actions have to former students of the Instituto Metodista Porto Alegre (IPA-RS)?" Its objective was to understand, grasp, and analyze the affirmative actions role and/or meaning to former students of this Brazilian private college institution, affiliated to the Centro Ecumênico de Cultura Negra (CECUNE). Secondly it aimed at knowing the African ancestrality through a systematic study; at approaching the relations between race/ethnicity and social class; at grasping the path/process of Black people´s struggles in Rio Grande do Sul and in Brazil; at analyzing the ways of those actions in the world, specifically in Brazil and in the United States. A case study was performed – in qualitative terms – by collecting data through questionnaires, interviews, meetings with former students, and analysis of documents from the research sites. Were also interviewed professors of The John Lewis Warfield Center for African and African American Studies at The University of Texas at Austin – USA and analyzed the bibliographic works about the thematic produced in this country. As a result, were found daily local habits arisen from the Africans past, which bring contributions to our society; in slavery times, maroon struggles emerged to abolish racial inequalities. Affirmative actions concepts differ – in ampleness and goals – in education, in labor market and in the diversity of social contact in social spaces. The conclusion was that race-ethnicity-social class relations form the tripod where the meanings of affirmative actions to former students are highlighted: professional future; family and personal future; a dream fulfillment; ways of identity reconstruction; unique opportunity; self-esteem improvement; socioeconomic progress, cultural withdrawal and life perspective. / La tesis tiene el punto central en las acciones afirmativas en la sociedad brasileña y problematiza: "¿Qué sentidos tienen para los egresos del Instituto Metodista Porto Alegre (IPA-RS) las Acciones Afirmativas?" Objetivo: entender, comprender, analizar su papel y/o sentido para egresos de esta Institución de Enseñanza Superior privada en Brasil, conveniada al Centro Ecumenico de Cultura Negra (CECUNE). Secundariamente objetiva: conocer por el estudio sistemático la ancestralidad africana; aproximar las relaciones entre raza/etnia y clase social; comprender el camino/proceso de luchas del pueblo negro afro-gaucho y brasileño; analizar los caminos de esas acciones en los espacios del mundo, específicamente Brasil y Estados Unidos. Estudio de caso - naturaleza cualitativa - colecta de datos por medio de cuestionarios, entrevistas, encuentro de egresos, y, analiza documentos de los sitios de la pesquisa. Entrevistas con profesores de The John Lewis Warfield Center for African and African American Studies at The University of Texas at Austin- USA y análisis de la producción bibliográfica de este país sobre la temática. Resultados: fueron descubiertas costumbres locales cotidianas, oriundas del pasado africano que dejan sus contribuiciones en nuestra sociedad; entre los tiempos de esclavitud, luchas quilombolas emergen en las/para aboliciones de las desigualdades. Conceptos de las acciones afirmativas se diferencian – en amplitud y metas – en la educación y en el mercado de trabajo y, en la diversidad del convivio en espacios sociales. Conclusiones: Relaciones raza-etnia-clase forman el trípode que se destacan como sentidos de la acción afirmativa para los egresos: futuro profesional; futuro familiar y personal; realización de un sueño; posibilidad de reconstrucción de identidad; oportunidad única; elevación de la autoestima; retractación cultural; avanzo socioeconómico y perspectiva de vida.

Ìsìnrú na ní bawo ohun pàtàkì na ise ìtenumó ni Brasili ati ìbi: "ki banújé ní fun àwon ki jadekúrò Instituto Metodista Porto Alegre (IPA-RS) àwon ise ìtenumó?" Èrò: yé, mó, túka ìwé ré ati/tabi banújé fun àwon jadekúrò ilá ìweé àgbá ni Brasili ki tó si Centro Ecumênico de Cultura Negra (CECUNE). Kan ekeji ibéèrè àwárì: mò nípa ikó àwon egúngun Afrika; kó bawo bi fifún àwon ohun lâárín èda ènià, arãlé ati egbé; mò, ònà àwon já ogun aráye Dudu gaúcho ati Brasili; túka àwon ònà ise wonyi ni ilê-ayé, ni Brasili ati Àwon Ìlú Fi Kún. Ekó àwon ohun – ìwádi ìrí – síbí àwon ohun nípa àwon ibéèrè, ìbi, pàdé àwon èniyàn ki jadekúrò, ati, túka àwon ìwé àwon ibi iwadí. Ibéèrè pèlú àwon olùkó The John Lewis Warfield Center for African and African Americen Studies at The University of Texas at Austin – USA ati túka ida sílè àwon ìwé ìlú eyi nípa ibéèrè. Àwon ìdáhùn: bá àwon asa ibi ojõjó ti dé ikoja Afrika ki kòsílè àdáwó ré nínú awa; nínú àwon àkókò àwon erú, àwon ja ogun quilombolas rú jade àwon ni/fun òmìnirà àwon ko ìbásededé – ni ìtóbi ati àwon àkója – ni ekó ati ni ojá ise ati, ni àwon onírúurú ni àwon ibi egbé. Àwon ìdáhùn: àwon ibéèrè èdá ènià-arãlé- egbé ni eta àwon ohun pàtàkì fun àwon ise ìtenumó fun àwon jadekúrò: èhin-òla isé; èhin-òla ebí ati ara; àlá da; èda titun ènia; titun àsìkò; pó si ife pàápàá; ìwé ìhòhìn àwon ohun egbé; pó si ìdàpò ati ìsúná ati ayé. / A tese tem o ponto central nas Ações Afirmativas na sociedade brasileira e problematiza: "Que sentidos têm para os egressos do Instituto Metodista Porto Alegre (IPA-RS) as Ações Afirmativas?" Seu objetivo foi entender, compreender, analisar o papel dessas ações e/ou o sentido que tem para os egressos dessa Instituição de Ensino Superior privada, no Brasil, conveniada com o Centro Ecumênico de Cultura Negra (CECUNE). De forma secundária, ela objetivava conhecer, pelo estudo sistemático, a ancestralidade africana; aproximar as relações entre raça/etnia e classe social; compreender o caminho/processo das lutas do povo negro afro-gaúcho e brasileiro; analisar os caminhos dessas ações no mundo, especificamente no Brasil e nos Estados Unidos. Foi feito um estudo de caso – de natureza qualitativa – mediante coleta de dados por meio de questionários, entrevistas, encontro de egressos e análise de documentos dos locais da pesquisa. Foram entrevistados professores do The John Lewis Warfield Center for African and African American Studies at The University of Texas at Austin – USA e analisada a produção bibliográfica desse país sobre a temática. Como resultados, foram descobertos costumes locais cotidianos oriundos do passado africano que deixaram suas contribuições em nossa sociedade; nos tempos da escravidão, lutas quilombolas emergiram na/para abolição das desigualdades. Os conceitos das ações afirmativas se diferenciam – em amplitude e metas – na educação, no mercado de trabalho e na diversidade do convívio em espaços sociais. Concluiu-se que as relações raça-etnia-classe formam o tripé onde se destacam como sentidos da ação afirmativa para os egressos: futuro profissional; futuro familiar e pessoal; realização de um sonho; possibilidade de reconstrução da identidade; oportunidade única; elevação da autoestima; retratação cultural; avanço socioeconômico e perspectiva de vida. / This dissertation has the central concern with the affirmative actions in the Brazilian society and problematizes: "What meanings do the affirmative actions have to former students of the Instituto Metodista Porto Alegre (IPA-RS)?" Its objective was to understand, grasp, and analyze the affirmative actions role and/or meaning to former students of this Brazilian private college institution, affiliated to the Centro Ecumênico de Cultura Negra (CECUNE). Secondly it aimed at knowing the African ancestrality through a systematic study; at approaching the relations between race/ethnicity and social class; at grasping the path/process of Black people´s struggles in Rio Grande do Sul and in Brazil; at analyzing the ways of those actions in the world, specifically in Brazil and in the United States. A case study was performed – in qualitative terms – by collecting data through questionnaires, interviews, meetings with former students, and analysis of documents from the research sites. Were also interviewed professors of The John Lewis Warfield Center for African and African American Studies at The University of Texas at Austin – USA and analyzed the bibliographic works about the thematic produced in this country. As a result, were found daily local habits arisen from the Africans past, which bring contributions to our society; in slavery times, maroon struggles emerged to abolish racial inequalities. Affirmative actions concepts differ – in ampleness and goals – in education, in labor market and in the diversity of social contact in social spaces. The conclusion was that race-ethnicity-social class relations form the tripod where the meanings of affirmative actions to former students are highlighted: professional future; family and personal future; a dream fulfillment; ways of identity reconstruction; unique opportunity; self-esteem improvement; socioeconomic progress, cultural withdrawal and life perspective. / La tesis tiene el punto central en las acciones afirmativas en la sociedad brasileña y problematiza: "¿Qué sentidos tienen para los egresos del Instituto Metodista Porto Alegre (IPA-RS) las Acciones Afirmativas?" Objetivo: entender, comprender, analizar su papel y/o sentido para egresos de esta Institución de Enseñanza Superior privada en Brasil, conveniada al Centro Ecumenico de Cultura Negra (CECUNE). Secundariamente objetiva: conocer por el estudio sistemático la ancestralidad africana; aproximar las relaciones entre raza/etnia y clase social; comprender el camino/proceso de luchas del pueblo negro afro-gaucho y brasileño; analizar los caminos de esas acciones en los espacios del mundo, específicamente Brasil y Estados Unidos. Estudio de caso - naturaleza cualitativa - colecta de datos por medio de cuestionarios, entrevistas, encuentro de egresos, y, analiza documentos de los sitios de la pesquisa. Entrevistas con profesores de The John Lewis Warfield Center for African and African American Studies at The University of Texas at Austin- USA y análisis de la producción bibliográfica de este país sobre la temática. Resultados: fueron descubiertas costumbres locales cotidianas, oriundas del pasado africano que dejan sus contribuiciones en nuestra sociedad; entre los tiempos de esclavitud, luchas quilombolas emergen en las/para aboliciones de las desigualdades. Conceptos de las acciones afirmativas se diferencian – en amplitud y metas – en la educación y en el mercado de trabajo y, en la diversidad del convivio en espacios sociales. Conclusiones: Relaciones raza-etnia-clase forman el trípode que se destacan como sentidos de la acción afirmativa para los egresos: futuro profesional; futuro familiar y personal; realización de un sueño; posibilidad de reconstrucción de identidad; oportunidad única; elevación de la autoestima; retractación cultural; avanzo socioeconómico y perspectiva de vida.

Ìsìnrú na ní bawo ohun pàtàkì na ise ìtenumó ni Brasili ati ìbi: "ki banújé ní fun àwon ki jadekúrò Instituto Metodista Porto Alegre (IPA-RS) àwon ise ìtenumó?" Èrò: yé, mó, túka ìwé ré ati/tabi banújé fun àwon jadekúrò ilá ìweé àgbá ni Brasili ki tó si Centro Ecumênico de Cultura Negra (CECUNE). Kan ekeji ibéèrè àwárì: mò nípa ikó àwon egúngun Afrika; kó bawo bi fifún àwon ohun lâárín èda ènià, arãlé ati egbé; mò, ònà àwon já ogun aráye Dudu gaúcho ati Brasili; túka àwon ònà ise wonyi ni ilê-ayé, ni Brasili ati Àwon Ìlú Fi Kún. Ekó àwon ohun – ìwádi ìrí – síbí àwon ohun nípa àwon ibéèrè, ìbi, pàdé àwon èniyàn ki jadekúrò, ati, túka àwon ìwé àwon ibi iwadí. Ibéèrè pèlú àwon olùkó The John Lewis Warfield Center for African and African Americen Studies at The University of Texas at Austin – USA ati túka ida sílè àwon ìwé ìlú eyi nípa ibéèrè. Àwon ìdáhùn: bá àwon asa ibi ojõjó ti dé ikoja Afrika ki kòsílè àdáwó ré nínú awa; nínú àwon àkókò àwon erú, àwon ja ogun quilombolas rú jade àwon ni/fun òmìnirà àwon ko ìbásededé – ni ìtóbi ati àwon àkója – ni ekó ati ni ojá ise ati, ni àwon onírúurú ni àwon ibi egbé. Àwon ìdáhùn: àwon ibéèrè èdá ènià-arãlé- egbé ni eta àwon ohun pàtàkì fun àwon ise ìtenumó fun àwon jadekúrò: èhin-òla isé; èhin-òla ebí ati ara; àlá da; èda titun ènia; titun àsìkò; pó si ife pàápàá; ìwé ìhòhìn àwon ohun egbé; pó si ìdàpò ati ìsúná ati ayé. / A tese tem o ponto central nas Ações Afirmativas na sociedade brasileira e problematiza: "Que sentidos têm para os egressos do Instituto Metodista Porto Alegre (IPA-RS) as Ações Afirmativas?" Seu objetivo foi entender, compreender, analisar o papel dessas ações e/ou o sentido que tem para os egressos dessa Instituição de Ensino Superior privada, no Brasil, conveniada com o Centro Ecumênico de Cultura Negra (CECUNE). De forma secundária, ela objetivava conhecer, pelo estudo sistemático, a ancestralidade africana; aproximar as relações entre raça/etnia e classe social; compreender o caminho/processo das lutas do povo negro afro-gaúcho e brasileiro; analisar os caminhos dessas ações no mundo, especificamente no Brasil e nos Estados Unidos. Foi feito um estudo de caso – de natureza qualitativa – mediante coleta de dados por meio de questionários, entrevistas, encontro de egressos e análise de documentos dos locais da pesquisa. Foram entrevistados professores do The John Lewis Warfield Center for African and African American Studies at The University of Texas at Austin – USA e analisada a produção bibliográfica desse país sobre a temática. Como resultados, foram descobertos costumes locais cotidianos oriundos do passado africano que deixaram suas contribuições em nossa sociedade; nos tempos da escravidão, lutas quilombolas emergiram na/para abolição das desigualdades. Os conceitos das ações afirmativas se diferenciam – em amplitude e metas – na educação, no mercado de trabalho e na diversidade do convívio em espaços sociais. Concluiu-se que as relações raça-etnia-classe formam o tripé onde se destacam como sentidos da ação afirmativa para os egressos: futuro profissional; futuro familiar e pessoal; realização de um sonho; possibilidade de reconstrução da identidade; oportunidade única; elevação da autoestima; retratação cultural; avanço socioeconômico e perspectiva de vida. / This dissertation has the central concern with the affirmative actions in the Brazilian society and problematizes: "What meanings do the affirmative actions have to former students of the Instituto Metodista Porto Alegre (IPA-RS)?" Its objective was to understand, grasp, and analyze the affirmative actions role and/or meaning to former students of this Brazilian private college institution, affiliated to the Centro Ecumênico de Cultura Negra (CECUNE). Secondly it aimed at knowing the African ancestrality through a systematic study; at approaching the relations between race/ethnicity and social class; at grasping the path/process of Black people´s struggles in Rio Grande do Sul and in Brazil; at analyzing the ways of those actions in the world, specifically in Brazil and in the United States. A case study was performed – in qualitative terms – by collecting data through questionnaires, interviews, meetings with former students, and analysis of documents from the research sites. Were also interviewed professors of The John Lewis Warfield Center for African and African American Studies at The University of Texas at Austin – USA and analyzed the bibliographic works about the thematic produced in this country. As a result, were found daily local habits arisen from the Africans past, which bring contributions to our society; in slavery times, maroon struggles emerged to abolish racial inequalities. Affirmative actions concepts differ – in ampleness and goals – in education, in labor market and in the diversity of social contact in social spaces. The conclusion was that race-ethnicity-social class relations form the tripod where the meanings of affirmative actions to former students are highlighted: professional future; family and personal future; a dream fulfillment; ways of identity reconstruction; unique opportunity; self-esteem improvement; socioeconomic progress, cultural withdrawal and life perspective. / La tesis tiene el punto central en las acciones afirmativas en la sociedad brasileña y problematiza: "¿Qué sentidos tienen para los egresos del Instituto Metodista Porto Alegre (IPA-RS) las Acciones Afirmativas?" Objetivo: entender, comprender, analizar su papel y/o sentido para egresos de esta Institución de Enseñanza Superior privada en Brasil, conveniada al Centro Ecumenico de Cultura Negra (CECUNE). Secundariamente objetiva: conocer por el estudio sistemático la ancestralidad africana; aproximar las relaciones entre raza/etnia y clase social; comprender el camino/proceso de luchas del pueblo negro afro-gaucho y brasileño; analizar los caminos de esas acciones en los espacios del mundo, específicamente Brasil y Estados Unidos. Estudio de caso - naturaleza cualitativa - colecta de datos por medio de cuestionarios, entrevistas, encuentro de egresos, y, analiza documentos de los sitios de la pesquisa. Entrevistas con profesores de The John Lewis Warfield Center for African and African American Studies at The University of Texas at Austin- USA y análisis de la producción bibliográfica de este país sobre la temática. Resultados: fueron descubiertas costumbres locales cotidianas, oriundas del pasado africano que dejan sus contribuiciones en nuestra sociedad; entre los tiempos de esclavitud, luchas quilombolas emergen en las/para aboliciones de las desigualdades. Conceptos de las acciones afirmativas se diferencian – en amplitud y metas – en la educación y en el mercado de trabajo y, en la diversidad del convivio en espacios sociales. Conclusiones: Relaciones raza-etnia-clase forman el trípode que se destacan como sentidos de la acción afirmativa para los egresos: futuro profesional; futuro familiar y personal; realización de un sueño; posibilidad de reconstrucción de identidad; oportunidad única; elevación de la autoestima; retractación cultural; avanzo socioeconómico y perspectiva de vida.

Cette thèse examine la responsabilité sociale des entreprises (RSE) par les entreprises de secteurs controverses. Dans le premier chapitre, on évalue les stratégies en RSE pour 565 entreprises de secteurs controverses de 1991 à 2013 en estimant la relation compensatoire entre Irresponsabilité Sociale des Entreprises (ISE) et RSE. On montre que ces entreprises tendent à compenser pour leur ISE en s'engageant dans des domaines stratégiques de RSE tels que la protection de l'environnement et le respect des communautés locales avec un manque d'engagement dans d'autres activités telles la gouvernance d'entreprise. Dans le deuxième chapitre, on examine si l'engagement RSE de 499 entreprises de secteurs controverses est susceptible de diminuer leur risque financier. Nos résultats montrent qu'un engagement RSE stratégique réduit le risque idiosyncratique et total pour certaines industries controversées et que le manque d'engagement dans les activités de gouvernance augmente leur risque. Le troisième chapitre examine la divulgation sociétale en tant que mécanisme de reddition de comptes dans le contexte d'un incident environnemental majeur. L'étude de cas des stratégies RSE utilisées par l'entreprise Canadienne En bridge, durant sa réponse a l'incident de déversement de parole en 2010 révèle que ses rapports RSE sont souvent optimistes et ne réussissent pas a décrire son incapacité à faire face aux problèmes de sécurité ayant entrainé l'incident; et ont aussi sous-estime le volume du déversement et la difficulté du nettoyage, ainsi mettant en question l'effet des activités RSE compare à l'effet de facteurs contextuels dans la protection de l'entreprise durant la crise. / This thesis is composed of three chapters that examine corporate social responsibility (CSR) within firms in controversial sectors. In the first chapter, we evaluate patterns of investment in CSR for 565 US publicly traded companies in eight controversial sectors between 1991 and 2013 by assessing the relationship between CSR and Corporate Social Irresponsibility (CSI). We show that firms in controversial sectors compensate for their CSI by engaging in strategic CSR areas such as environmental protection and community development with a lack of engagement towards other areas, such as corporate governance. In the second chapter, we determine whether engagement in specific CSR activities for 499 US companies in controversial sectors decreases their financial risk. We show that engaging in specific CSR activities considered as strategic reduces idiosyncratic and total risk for some controversial industries; and that poor engagement in corporate governance activities increases firm risk. In the third chapter, we investigate CSR reporting as an important mechanism for stakeholder accountability in the context of an environmental crisis. We perform a case study analysis of the CSR strategies used by the Canadian oil company Enbridge in its response to the July 2010 Kalamazoo spill and revealed that Enbridge's CSR reports were frequently optimistic and failed to describe the company's inability to deal with known safety problems that led to spill; and underestimated both the volume of the spill and the difficulty of the cleanup, thus making it difficult to distinguish the effects of the CSR efforts from the effects of other contextual and external factors.

<p>The development of reliable, robust and low-cost sensor devices is growing in importance and an ongoing challenge. From environmental monitoring and household safety to food and biopharmaceutical industries, the necessity for specific analyte detection is crucial. Over the years researchers have come up with myriad materials that can be used for efficient sensing devices. The materials employed are governed by application and performance criteria as well as the sensing mechanism, which might be based on physical or chemical principles. In this thesis, two different types of electrochemical sensor technologies were examined with special attention paid to the application of the devices, the materials used, and their feasibility for scalable manufacturing.</p> <p>In the first study, binary mixtures of conducting and semiconducting nanomaterials were explored as promising candidates for the manufacturing of low-cost ethylene sensor on flexible substrates. Ethylene (C2H4) is a small plant hormone which has been shown to affect the growth and senescence of flowers, leaves and fruits. Currently available devices have demonstrated high ethylene sensitivities with great potential for technology size reduction; however, some are not practical for use outside of the laboratory, lack portability, or require more research to demonstrate their reproducibility and stability in different environments, as well as selectivity to C2H4 in large-scale applications. Conductometric gas sensors based on a combination of carbon nanotubes (CNTs) and exfoliated molybdenum disulfide (MoS2) coated with molecular receptors is demonstrated for the selective detection of ethylene, including details on materials preparation, manufacturing, and characterization. Mixtures of CNTs and exfoliated MoS2 were deposited onto screen-printed interdigitated electrodes on plastic substrates, with optimization for scalable and continuous manufacturing by roll-to-roll methods. C2H4 detection levels of 0.1 ppm were readily achieved with responses on the second timescale.</p> <p>The second sensor technology shows how thin-film potentiometric electrodes based on ion-selective membranes can be designed to tolerate sterilizing radiation while providing excellent performance and signal stability. This sensor's development was motivated by the expanding need for single-use bioreactor systems in the biopharmaceutical industry, which require strict control over cell culture conditions for several weeks or more. Until recently, critical analysis has been conducted mostly by offline or “at-line” sampling of aliquots withdrawn from the sterile bioreactor. The latter is inefficient and can increase the risk of contamination. Inspired by the challenges related to cost, integration and performance following irradiation a potentiometric pH electrode was developed, intended for single-use applications. It was shown to be radiation-tolerant while providing reliable data comparable to a commercial pH meter over a period of three months. The electrodes exhibited quasi-linear signal drifts of +0.28 mV/day or 0.005 pH units/day. Thin-film γ-irradiated electrodes could provide accurate pH readings in sterilized culture media using a single-point calibration, within 0.07 pH units of a commercial meter with glass electrode and daily calibration. Furthermore, to advance the development of market-ready sensors past the conceptual stage, a few automated processes for scalable membrane deposition were investigated.</p>