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Uma introdução ao movimento do neoateísmo : definições e metatesesSantos, Valmor Ferreira 24 February 2016 (has links)
This master's thesis in religious studies titled An Introduction to movement of New
Atheism: definitions and metatheses aims to present an introduction to very basic
problems New Atheism (NAT). The NAT is commonly associated to four people,
namely Sam Harris, Richard Dawkins, Daniel Dennett and Christopher Hitchens are
considered the fathers of this set of ideas about religion. The object of this dissertation
is not primarily the theses sustained by these intellectuals, but to understand the NAT
itself. Regarding the research methodology is conceptual in nature, not empirical, but
draws on historical and sociological research on the subject. After noting that there is
great divergence in the literature and in the media of how to understand the NAT
established in the first chapter a minimum concept of 'atheism' and the second 'New
Atheism'. In the last chapter, the third, we discuss some metatheses, general claims
about the NAT. We conclude that atheism should be understood among other properties
such as the absence of belief in God or the gods. The NAT even if not defined, it can be
understood as a group of theses with family resemblance. Finally, in relation to
metatheses, partially agree with Zenk that NAT is a media construction; LeDrew also
with a social movement that is fundamentally an ideology. However, we disagree with
Paine and Nall that such a move is a fundamentalism as defined by both authors. We
hope that this work is a contribution to the study of atheism in our country. / Esta dissertação tem como objetivo apresentar uma introdução a problemas muito
básicos do neoateísmo (NAT). O NAT está associado comumente a quatro intelectuais,
a saber, Sam Harris, Richard Dawkins, Daniel Dennett e Christopher Hitchens, que são
considerados os genitores desse conjunto de ideias a respeito da religião. O objeto desta
dissertação não é primariamente examinar as teses sustentadas por esses autores, mas
compreender o próprio NAT. Em relação à metodologia da pesquisa, é de índole
conceitual, não empírica, porém se vale de pesquisas históricas e sociológicas a respeito
do tema. Após observar que há grande divergência na literatura e na mídia sobre como
entender o NAT, estabelecemos no primeiro capítulo um conceito mínimo de “ateísmo”
e no segundo um de “neoateísmo”. No último capítulo, o terceiro, discutimos algumas
metateses – alegações gerais a respeito do NAT. Concluímos que o ateísmo deve ser
entendido como apresentando, entre outras características, a ausência da crença em
Deus ou nos deuses. Podemos compreender o NAT, mesmo que não o definindo, como
um grupo de teses com semelhança de família. Por fim, em relação às metateses,
concordamos parcialmente com Zenk que o NAT é uma construção da mídia;
igualmente com LeDrew, quando este autor postula que é um movimento social,
fundamentalmente uma ideologia. Porém, discordamos de Paine e Nall, de que tal
movimento seja um fundamentalismo, como definido por ambos os autores. Esperamos
que este trabalho contribua para os estudos sobre o ateísmo em nosso país. / São Cristóvão, SE
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Effect of chlorinating agents on purity of Zirconium tetrachloride produced from Zirconium tetrafluorideMakhofane, Milton Molahlegi 06 1900 (has links)
Zirconium tetrachloride (ZrF4) is extensively used in the manufacturing of zirconium metal. The concept of producing zirconium tetrafluoride from dissociated zircon and ammonium bifluoride is well established at the South African Nuclear Energy Corporation (Necsa) State Owned Company (SOC) Limited. Zirconium and hafnium are always found in the same minerals. In nuclear application zirconium is used for structural construction and as a cladding material for fuel, because of the low thermal neutron absorption, while hafnium is used as control rod in nuclear reactor, because of the high thermal neutron absorption. The methods of separating hafnium from zirconium prefer the use of ZrCl4 than ZrF4. This is because of the high solubility in both aqueous solutions and organic solvents and low sublimation temperature of ZrCl4, while ZrF4 is almost insoluble in organic solvent and has a high sublimation temperature. Thermodynamic evaluations showed that chlorinating ZrF4 with either CaCl2, KCl, LiCl or NaCl respectively was not favourable, while chlorinating ZrF4 with either BeCl2 or MgCl2 was favourable. But due to cost consideration chlorinating ZrF4 with BeCl2 was not investigated. A thermogravimetric apparatus was used to investigate the isothermal and the non-isothermal kinetics of chlorinating analytical grade ZrF4 with MgCl2. The thermogravimetric apparatus revealed that chlorination of ZrF4 commence at temperature above 350°C. Isothermal kinetics of chlorinating analytical grade ZrF4 with MgCl2 was investigated at temperatures of 400, 450, 480, 500°C. The reaction progressed towards completion prematurely before the isothermal temperatures were reached, due to a low heating rate of 20 °C/minutes was used to heat up the reaction mixture to the desired isothermal temperatures. As a result, the isothermal kinetics could not be determined. Heating rates of 5, 10, 15 and 20 °C/minutes were used to investigate the non-isothermal kinetics. The apparent activation energy of chlorinating ZrF4 with MgCl2 varied significantly when the non-isothermal kinetics was investigated. The variation was due to changes in the reaction mechanism. As a result, rate law of chlorinating ZrF4 with MgCl2 could not be determined due to variation of the apparent activation energy. Crude ZrF4 prepared at Necsa SOC ltd. was chlorinated with MgCl2, a mixture of MgCl2 and KCl, a mixture of MgCl2 and LiCl, and a mixture of MgCl2 and NaCl respectively. Chlorination of the crude ZrF4 was conducted at temperatures of 400, 450 and 500°C respectively. The aim of chlorinating the crude ZrF4 was to investigating the effect of the chlorinating on the purity of the produced ZrCl4. A batch reactor was used in this study. The reactor was divided into two sections, namely the reaction zone and the condensation zone. The diameter of the condensation zone was larger than that of the reaction zone. Reactants were placed into the reaction zone and the products were collected at the reaction zone and the condensation zone. Samples were collected from these products and analysed using for X-Ray Diffraction analysis (XRD) and Inductive Coupled Plasma Optical Emissions Spectroscopy (ICP-OES). XRD was used to identify the compounds that were present in the products and ICP-OES was used to determine the concentration of the elements that were present in the products. The analysis of the results obtained showed that the highest recovery of zirconium in the products collected from the condensation zone, the sublimed products, was achieved by chlorinating ZrF4 with MgCl2 at 500°C. About 80% was recovered. About 96% of the concentration of the impurities in the sublimed products was reduced when ZrF4 was chlorinated with a mixture of MgCl2 and LiCl at 450°C. About 36% of hafnium in the sublimed products was reduced when ZrF4 was chlorinated with a mixture of MgCl2 and NaCl at 400°C. / Chemical Engineering / M.Tech. (Chemical Engineering)
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Effect of chlorinating agents on purity of Zirconium tetrachloride produced from Zirconium tetrafluorideMakhofane, Milton Molahlegi 06 1900 (has links)
Zirconium tetrachloride (ZrF4) is extensively used in the manufacturing of zirconium metal. The concept of producing zirconium tetrafluoride from dissociated zircon and ammonium bifluoride is well established at the South African Nuclear Energy Corporation (Necsa) State Owned Company (SOC) Limited. Zirconium and hafnium are always found in the same minerals. In nuclear application zirconium is used for structural construction and as a cladding material for fuel, because of the low thermal neutron absorption, while hafnium is used as control rod in nuclear reactor, because of the high thermal neutron absorption. The methods of separating hafnium from zirconium prefer the use of ZrCl4 than ZrF4. This is because of the high solubility in both aqueous solutions and organic solvents and low sublimation temperature of ZrCl4, while ZrF4 is almost insoluble in organic solvent and has a high sublimation temperature. Thermodynamic evaluations showed that chlorinating ZrF4 with either CaCl2, KCl, LiCl or NaCl respectively was not favourable, while chlorinating ZrF4 with either BeCl2 or MgCl2 was favourable. But due to cost consideration chlorinating ZrF4 with BeCl2 was not investigated. A thermogravimetric apparatus was used to investigate the isothermal and the non-isothermal kinetics of chlorinating analytical grade ZrF4 with MgCl2. The thermogravimetric apparatus revealed that chlorination of ZrF4 commence at temperature above 350°C. Isothermal kinetics of chlorinating analytical grade ZrF4 with MgCl2 was investigated at temperatures of 400, 450, 480, 500°C. The reaction progressed towards completion prematurely before the isothermal temperatures were reached, due to a low heating rate of 20 °C/minutes was used to heat up the reaction mixture to the desired isothermal temperatures. As a result, the isothermal kinetics could not be determined. Heating rates of 5, 10, 15 and 20 °C/minutes were used to investigate the non-isothermal kinetics. The apparent activation energy of chlorinating ZrF4 with MgCl2 varied significantly when the non-isothermal kinetics was investigated. The variation was due to changes in the reaction mechanism. As a result, rate law of chlorinating ZrF4 with MgCl2 could not be determined due to variation of the apparent activation energy. Crude ZrF4 prepared at Necsa SOC ltd. was chlorinated with MgCl2, a mixture of MgCl2 and KCl, a mixture of MgCl2 and LiCl, and a mixture of MgCl2 and NaCl respectively. Chlorination of the crude ZrF4 was conducted at temperatures of 400, 450 and 500°C respectively. The aim of chlorinating the crude ZrF4 was to investigating the effect of the chlorinating on the purity of the produced ZrCl4. A batch reactor was used in this study. The reactor was divided into two sections, namely the reaction zone and the condensation zone. The diameter of the condensation zone was larger than that of the reaction zone. Reactants were placed into the reaction zone and the products were collected at the reaction zone and the condensation zone. Samples were collected from these products and analysed using for X-Ray Diffraction analysis (XRD) and Inductive Coupled Plasma Optical Emissions Spectroscopy (ICP-OES). XRD was used to identify the compounds that were present in the products and ICP-OES was used to determine the concentration of the elements that were present in the products. The analysis of the results obtained showed that the highest recovery of zirconium in the products collected from the condensation zone, the sublimed products, was achieved by chlorinating ZrF4 with MgCl2 at 500°C. About 80% was recovered. About 96% of the concentration of the impurities in the sublimed products was reduced when ZrF4 was chlorinated with a mixture of MgCl2 and LiCl at 450°C. About 36% of hafnium in the sublimed products was reduced when ZrF4 was chlorinated with a mixture of MgCl2 and NaCl at 400°C. / Chemical Engineering / M.Tech. (Chemical Engineering)
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