Dissertations / Theses: 'Feodor'

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Simitopol, Anca Eliza. "Ideas of Community in the Thought of Pierre Leroux and of Feodor Dostoevsky: Agape, Philia and Eros." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23280.

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In this thesis I compare Pierre Leroux, a French utopian socialist (1797 – 1871), with Feodor Dostoevsky, the well-known Orthodox Russian novelist (1821 – 1881). I argue that both authors reacted against what they considered to be the dissolution of the social order, brought about by the increasing nineteenth-century bourgeois individualism. On the other hand, they reacted as well against the opposite phenomenon, the idea of a universal socialist state, which was, in fact, according to them, the outcome of bourgeois individualism. My purpose is to bring close and to compare Leroux’s republican socialism with Dostoevsky’s Christian socialism, and to explore to what extent the two authors give similar answers to a common problem. In order to better explain their thought, I divide my thesis into three chapters. The first analyzes and compares Leroux’s and Dostoevsky’s critiques of individualism. If Leroux reaches the conclusion that the ultimate expression of individualism is Malthusianism, Dostoevsky argues that individualism ends in nihilism. The second chapter analyzes the type of socialism against which Leroux and Dostoevsky reacted, as well as the critiques of the two authors. I argue here that Saint-Simonian socialism – the main object of Leroux’s critique – and the socialism of the Grand Inquisitor – a Dostoevskyan character – are the expression of a certain utopian thought which considers the requirement for freedom incompatible with the requirement for unity. In the last chapter, I analyze the ideas of community of Leroux and of Dostoevsky, which are centered on philia, in the case of the former, and on agape, in the case of the latter. Philia and respectively agape are the expression of organic social relations, through which the two requirements, of freedom and unity, are made compatible, and which create unity in multiplicity. Their ideas of community appear as active utopias, grounded on the life of relation in a spontaneous, organic community.

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Wilgenbus, Erich Feodor. "The file fragment classification problem : a combined neural network and linear programming discriminant model approach / Erich Feodor Wilgenbus." Thesis, North-West University, 2013. http://hdl.handle.net/10394/10215.

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The increased use of digital media to store legal, as well as illegal data, has created the need for specialized tools that can monitor, control and even recover this data. An important task in computer forensics and security is to identify the true le type to which a computer le or computer le fragment belongs. File type identi cation is traditionally done by means of metadata, such as le extensions and le header and footer signatures. As a result, traditional metadata-based le object type identi cation techniques work well in cases where the required metadata is available and unaltered. However, traditional approaches are not reliable when the integrity of metadata is not guaranteed or metadata is unavailable. As an alternative, any pattern in the content of a le object can be used to determine the associated le type. This is called content-based le object type identi cation. Supervised learning techniques can be used to infer a le object type classi er by exploiting some unique pattern that underlies a le type's common le structure. This study builds on existing literature regarding the use of supervised learning techniques for content-based le object type identi cation, and explores the combined use of multilayer perceptron neural network classi ers and linear programming-based discriminant classi ers as a solution to the multiple class le fragment type identi cation problem. The purpose of this study was to investigate and compare the use of a single multilayer perceptron neural network classi er, a single linear programming-based discriminant classi- er and a combined ensemble of these classi ers in the eld of le type identi cation. The ability of each individual classi er and the ensemble of these classi ers to accurately predict the le type to which a le fragment belongs were tested empirically. The study found that both a multilayer perceptron neural network and a linear programming- based discriminant classi er (used in a round robin) seemed to perform well in solving the multiple class le fragment type identi cation problem. The results of combining multilayer perceptron neural network classi ers and linear programming-based discriminant classi ers in an ensemble were not better than those of the single optimized classi ers.
MSc (Computer Science), North-West University, Potchefstroom Campus, 2013

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Beisegel, Jesse [Verfasser], Ekkehard [Gutachter] Köhler, Feodor [Gutachter] Dragan, and Michel [Gutachter] Habib. "Convexity in graphs: vertex order characterisations and graph searching / Jesse Beisegel ; Gutachter: Ekkehard Köhler, Feodor Dragan, Michel Habib." Cottbus : BTU Cottbus - Senftenberg, 2020. http://d-nb.info/1206936959/34.

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Braun, Feodor [Verfasser], Ines [Gutachter] Neundorf, and Fabian [Gutachter] Mohr. "Multimodale radioaktive Konstrukte zur Diagnostik und Therapie von Mamma- und Prostatakarzinomen / Feodor Braun ; Gutachter: Ines Neundorf, Fabian Mohr." Köln : Universitäts- und Stadtbibliothek Köln, 2019. http://d-nb.info/1217402802/34.

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Rivas, Márcia Guimarães. "Sofrimento e sentido: uma clínica fenomenológica de Ivan Karamázov." Pontifícia Universidade Católica de São Paulo, 2006. https://tede2.pucsp.br/handle/handle/1985.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The present dissertation seeks to grasp the relation between suffering and meaning in the Human condition in Dostoiévski s The Brothers Karamázov , with a particular emphasis on its significance to modern man as well as the purpose of finding a place for a possible contribution from the clinical practice of phenomenology. For that purpose I make use of the method of existential phenomenology in an effort to grasp the intentionality issues involved. In the first chapter I strive to understand Dostoiévski s work in the light of its Russian Orthodox sources, dealing with the authors who studied and commented it and concentrating in further detail on the reading of such categories as suffering, Christianity and Human condition as they appear in this masterpiece of Russian Literature. The Second Chapter is a descriptive compilation of the life of Ivan Karamázov (the main carachter of the book) followed by a phenomenological analysis of his personality and actions, whereby one is led to see how the failure of the notion of Man s sufficiency, which the carachter embodies, and his increasing alienation from the supernatural source of his being, is likely to tear him apart as he seeks to avoid the Human consequences of his passions. Finally, in Chapter 3, I endeavour, in the light of my prime subjects, i.e., suffering and meaning, to establish how Dostoiévski s thought, the main carachter of his book and modern man may be referred to each another, what leads me to the conclusion that the meaning of suffering resides not in suffering itself, but in Man s attitude towards it, be it one of confrontation or denial, acceptance or revolt. Although it in fact exists, is necessary and cannot be denied (denial of suffering is dangerous as it may lead to greater, infernal suffering), suffering is no drive to transformation apart from the diverse meanings which may be attributed to it. Nevertheless, for its acceptance and transformation to be operative, the supernatural aspect in the Human condition must be incorporated. Psycotherapy may contribute to this process of Man s self-revelation by facilitating the first step: not lying to one s self
Nesta dissertação buscamos compreender a relação entre sofrimento e sentido da condição humana, em que pudéssemos transpor a questão para o sofrimento do homem moderno, com a finalidade de encontrar um lugar de contribuição da clínica fenomenológica, em seu entendimento. Para tal, utilizamos o método da fenomenologia existencial de compreensão do fenômeno, de busca de compreensão de intencionalidade. No primeiro capítulo, buscamos a compreensão da ortodoxia e da obra dostoievskiana, através dos autores que trabalham estas questões, focando-nos mais detidamente na leitura do sofrimento, do cristianismo e da condição humana. O segundo capítulo foi uma compilação descritiva da vida de Ivan Karamázov e a subseqüente análise fenomenológica da personagem, quando pudemos testemunhar o fracasso da mentira de suficiência do homem, esquecido de sua sobrenatureza, desaguando em cisão e despedaçamento, no evitamento de suportar suas paixões. Por fim, trabalhamos a tessitura da discussão entre o pensamento dostoievskiano, a personagem na obra e o homem na modernidade, à luz do sofrimento e sentido. Após ter feito este percurso e concluído os resultados, podemos afirmar que o sentido do sofrimento está na atitude que temos diante dele, de enfrentamento ou negação, de aceitação ou revolta. O que nos transforma não é o sofrimento, mas o sentido que damos a ele. Mas, sem sombra de dúvidas, o sofrimento é necessário para que possamos dar sentido e nos transformar em pessoas melhores. O sofrimento existe, é necessário, e negá-lo é garantia de um sofrimento maior ainda, um sofrimento infernal. Portanto, para esta aceitação e transformação pelo sofrimento, o resgate da condição de sobrenatureza é imprescindível. A psicoterapia pode contribuir quando em seu processo de desvelamento o individuo dá seu primeiro passo: o de não mentir a si mesmo

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Sakamoto, Jacqueline Izumi. "Religião e niilismo: paidéia crítica em Os demônios de Dostoiévski." Pontifícia Universidade Católica de São Paulo, 2007. https://tede2.pucsp.br/handle/handle/2046.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Objective: To deal with the philosophy of the religion in Dostoiévski as a testimony, that not only discloses a powerful religious criticism to the modern atheism unfolding, but still, extending our repertoire, for the access to this religious thinker as form to know the religion. Justification: In The Devils, Dostoiévski treats the excesses of education and ethics secularization indicating the holiness category forgetfulness, characterized mainly by the symmetry relation between man and the transcendent, the atheism as an anthropocentric legacy of the modern rational project, produces moral myopia rendering useless the discernment amid the relativity chaos. Hypothesis: The nihilism dynamic, characterizes the visceral movements of human being towards self-destruction, is rooted in what Berdiaev defined as an uncreated liberty, where sprout our Imago Dei, not subject to the norms, that inhabits human soul with the Nothing. We will try to show that the path through Nothing, the reality of the sin and the evil is considered the axis of Dostoiévskis pedagogy, constitutes a critical and religious Paideia. Theoretical-methodological aspects and obtained result: As a procedure this research deepened the sense of the work interpretation, and the characters dynamic, by the analysis of its content a narrow relation and dialogue amongst the prominent theoretical yardsticks for the comprehension of the theological foundations presented in the thought of Dostoiévski. In this sense, the obtained result reached the proposed objective: the clash of modern atheism with the instruments of the philosophy of religion that seeks an extended comprehension as a necessary repertoire for the dialogue between education, religion and moral, a critical Paideia, and still, the up to date depth of this work for the contemporary man
Objetivo: Tratar a filosofia da religião em Dostoiévski como um testemunho, que nos revela não só uma poderosa crítica religiosa aos desdobramentos do ateísmo moderno, mas ainda, ampliando nosso repertório, pelo acesso a este pensador religioso como forma de conhecer a religião. Justificativa: Dostoiévski trata em Os Demônios os excessos da secularização em ética e pedagogia e indica que o esquecimento da categoria de santidade, caracterizada principalmente pela relação de simetria entre o homem e o transcendente, o ateísmo como legado antropocêntrico do projeto racional moderno, produz miopia moral inviabilizando o discernimento em meio ao caos relativista. Hipótese: A dinâmica do niilismo, caracterizando os movimentos viscerais do ser humano em processo de auto-destruição, está enraizado no que Berdiaev definiu como liberdade incriada, de onde brota nossa Imago Dei, não passível às normas, que habita a alma humana com o Nada. Procuraremos demonstrar que o atravessamento deste Nada, o eixo da pedagogia dostoiévskiana que considera a realidade do pecado e do mal, constitui uma Paidéia crítica e religiosa. Aspectos teórico-metodológicos e resultado obtido: Como procedimento esta pesquisa aprofundou a interpretação do sentido da obra, e da dinâmica dos personagens, pela análise de seu conteúdo, em estreita relação e diálogo com os referenciais teóricos relevantes para a compreensão dos fundamentos teológicos presentes no pensamento de Dostoiévski. Neste sentido, o resultado obtido atingiu o objetivo proposto: o enfrentamento do ateísmo moderno com os instrumentos da filosofia da religião, que busca uma compreensão ampliada como repertório necessário para o diálogo entre educação, religião e moral, constitui uma Paidéia crítica, e identificou ainda, a atualidade desta obra para o homem no mundo contemporâneo

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Tatar, Säde. "Säde Tatar examensarbete BLÅS ÖSTANVIND : Spilåpipare Sväs Anders Ersson." Thesis, Kungl. Musikhögskolan, Institutionen för folkmusik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kmh:diva-4196.

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Konserten ägde plats 4 juni kl 19 i Lilla salen, KMH. Blev livestreamad via KMHs Youtubekanal.

1. Sövlåten efter Nygårds Karin Persson från Öje, Dalarna (Säde Tatar - svensk säckpipa)2. Suomela gånglåt Musik: Säde Tatar (Säde Tatar - svensk säckpipa, Vega Nordkvist – fiol, Coline Genet – fiol, Gabbi Dluzewski – låtmandola) F#-mollpolskan Musik: Säde Tatar Arr: Säde Tatar & Gabbi Dluzewski (Säde Tatar - Åspipa, Gabbi Dluzewski – låtmandola) 3. Tulvil Musik & arr: Säde Tatar & Gabbi Dluzewski (Säde Tatar - tvärflöjt, Gabbi Dluzewski – låtmandola 4. Jouhikkolåtar efter Feodor Pratsu från Impilahti, Karelen (Säde Tatar - sälgflöjt)5. Krångelpolska efter Ol ́Jansa och Andreas Lång, Haverö Komposition: Göran Månsson (Säde Tatar - tvärflöjt) 6. Halia soitto efter Natalia Vassili, Ingermanland (Säde Tatar - Åspipa)7. Tantsukollena efter Natalia Vassili, Ingermanland (Säde Tatar - Åspipa, Göran Månsson – spelpipa)8. Kratitöö Musik: Säde Tatar (Säde Tatar - Härjedalspipa, Vega Nordkvist – fiol, Coline Genet – fiol, Göran Månsson – härjedalspipa, Gabbi Dluzewski – låtmandola)9. Rabatud Musik: Säde TatarArr: FRÄNDER (Säde Tatar - altflöjt, Daniel Dluzewski – kontrabas, Alva Granstörm – fiol, Andreas Berglund – slagverk, Gabbi Dluzewski – låtmandola 10. Õhtu õrna Musik: Säde Tatar Text: estnisk trad. från Viru-Jaagupi Arr: FRÄNDER (Säde Tatar - sång, tvärflöjt, Daniel Dluzewski – kontrabas, Alva Granstörm – fiol, Andreas Berglund – slagverk, Gabbi Dluzewski – låtmandola)11. Kung Björns polska Musik: Gabbi Dluzewski Arr: FRÄNDER (Säde Tatar - mungiga, tvärflöjt, Daniel Dluzewski – kontrabas, Alva Granstörm – fiol, Andreas Berglund – slagverk, Gabbi Dluzewski – låtmandola)12. Evigt regn Musik: Gabbi Dluzewski Text: Natasja Dluzewska Arr: FRÄNDER (Säde Tatar -- tvärflöjt, Daniel Dluzewski – kontrabas, Alva Granstörm – fiol, Andreas Berglund – slagverk, Gabbi Dluzewski – låtmandola)

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Teti, Feodora [Verfasser], and Gabriel [Akademischer Betreuer] Felbermayr. "Essays in international economics / Feodora Francesca Angelika Teti ; Betreuer: Gabriel Felbermayr." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2020. http://nbn-resolving.de/urn:nbn:de:bvb:19-264323.

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Teti, Feodora Francesca Angelika [Verfasser], and Gabriel [Akademischer Betreuer] Felbermayr. "Essays in international economics / Feodora Francesca Angelika Teti ; Betreuer: Gabriel Felbermayr." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2020. http://d-nb.info/1215500025/34.

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Hauk, Helen Feodora Sweta [Verfasser]. "Analyse von metaplastischen Paneth-Zellen im Kolon bei Patienten mit Morbus Crohn / Helen Feodora Sweta Hauk." Tübingen : Universitätsbibliothek Tübingen, 2021. http://d-nb.info/1225740029/34.

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Barros, Andrea de. "A dúvida em discursividade: Machado de Assis e Dostoiévski." Pontifícia Universidade Católica de São Paulo, 2007. https://tede2.pucsp.br/handle/handle/14811.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
The present essay is constituted of an analisis of the theme of the construction of the doubt in Dostoevsky s The Eternal Husband (1870) and in Machado de Assis s Dom Casmurro (1899), following the concepts of polifony and dialogism, created by Mikhail Bakhtin. It is orientated by the following objectives: studying the dialogical relations between the emissor discourse (authors voice), the narrator and the characters, focusing their implications in the construction of the doubt in the romances of the corpus; investigating the forms through which the senses of the doubt are recreated in both narratives; analizing the logical procedures of the enounciation, by which José Dias guides Bentinho s discourse, as Trussotzki guides Vieltchaninov s discourse, studying the aplication of these procedures to the construction of the doubt in both romances; and, finally, contributing to the reflections about the literature of Machado de Assis and Dostoevsky, through a critical reading of the books in study. The research is orientated by the following hypothesis: José Dias acts as an aggregation to Bentinhos s conscience, in Dom Casmurro, and Trussotzki acts as an aggregation to Vieltchaninov s conscience, in The Eternal Husband. The metodological approach is the dialogical one, by which it is created a dialog among the romances. Otherwise, the manners and functions of this aggregation are specifically differents on each narratives. This study defends that, in the high level of dialogism of their romanesque speeches, Machado and Dostoevsky are pairs, and considers that, as Dostoevsky is the founder of the polyphonic romance and the greatest example of dialogism in the literary universe, Machado can be recognized as the precursor of the same genre in Brazilian Literature
Este trabalho constitui-se de uma análise do tema da construção da dúvida nos romances O Eterno Marido (1870) de Dostoiévski e Dom Casmurro (1899) de Machado de Assis, à luz da polifonia e do dialogismo, de Mikhail Bakhtin. Pauta-se pelos seguintes objetivos: estudar as relações dialógicas entre os discursos do emissor (voz autoral), do narrador e do destinatário (personagens) e suas implicações na construção da dúvida nos romances do corpus; investigar as formas por meio das quais os sentidos de conotação da dúvida e da suspeita do adultério são recriados nas duas narrativas; analisar os procedimentos lógicos da enunciação pelos quais a personagem José Dias orienta o discurso de Bentinho, à semelhança de como Trussótzki orienta o de Vieltchâninov, e estudar as implicações da aplicação desses procedimentos à construção da dúvida em ambos os romances; e, finalmente, contribuir para as reflexões sobre as escrituras de Machado de Assis e de Dostoiévski, a partir de uma leitura crítica das obras em estudo. A pesquisa orienta-se pela seguinte hipótese: José Dias atua como um agregado de consciência de Bentinho, em Dom Casmurro, e Trussótzki atua como agregado de consciência de Vieltchâninov, em O Eterno Marido. A metodologia aplicada é a dialógica, por meio da qual se estabelece um diálogo entre os romances. Entretanto, conclui-se que as formas e as funções desse agregamento se configuram de maneiras específicas e diferentes em cada narrativa. O estudo defende que, no alto grau de dialogismo de seus discursos romanescos, Machado e Dostoiévski se encontram como pares e considera que, assim como Dostoiévski é o fundador do romance polifônico e exemplo máximo de dialogismo no universo literário, segundo Bakhtin, Machado pode ser reconhecido como precursor, na Literatura Brasileira, deste mesmo gênero

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Nováky, György. "Handelskompanier och kompanihandel : svenska Afrikakompaniet 1649-1663 : en studie i feodal handel /." Uppsala : Stockholm : Universitetet ; Almqvist & Wiksell International, distributor, 1990. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=003326951&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Novaky, György. "Handelskompanier och kompanihandel : svenska Afrikakompaniet 1649-1663, en studie i feodal handel /." Stockholm : Almqvist och Wiksell, 1990. http://catalogue.bnf.fr/ark:/12148/cb355129917.

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Al-Zahrani, Abdulnaser A. "Chloride ion removal from archaeological iron and #beta#-FeOOH." Thesis, Cardiff University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313137.

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The stabilisation of archaeological iron is considered as one of the major problems facing the archaeological conservator today. Free chlorides, held as counter ions at the metallic anode, act as electrolytes and promote corrosion of metallic iron This study examines and compares the efficiency of a range of aqueous wash methods currently used to remove chloride ions from archaeological iron and determines how these various treatments work. It also investigates the effect of selected aqueous wash treatments on the chloride rich metastable corrosion product 0-FeOOH. The amount of Cl'removed from 0-FeOOH and any transformations to new compounds are recorded. Iron objects were treated using aqueous Soxhlet extraction with nitrogen, aqueous sodium hydroxide and aqueous alkaline sulphite solutions. Synthetic O-FeOOH and PFeOOH1Fe3Om4 ixtures were washed in aqueouss odium hydroxide, aqueousa lkaline sulphite solution, aqueous sodium sulphite, hot and cold deionised water. The outcome of the work showed that: (1) For archaeological iron objects: O. SM nitrogen de-aerated aqueous NaOH solutions are very efficient chloride extractors, often approaching a 100% efficiency. Almost as efficient were 0.5M aqueous... NaOH/Na2SO3 treatment solutions. Nitrogen de-aeration of treatment solutions improves their cr extraction efficiency, by freeing Cl' from its counter ion role. Hydroxide ions improve extraction efficiency of Cl- from iron objects in nitrogen and Na2S03 de-aerated environments. The de-aerated aqueous Soxhlet extraction method, as suggested by Scott and Seeley (1986), is a less efficient chloride extractor than either nitrogen de-aerated 0.5M NaOH or 0.5M NaOH/Na2SO3. De-aerated NaOH treatment solutions are to be preferred to NaOH/Na2SO3 solutions, as they do not introduce residual electrolyte ions (SO 42). (2) For O-FeOOH samples: Pure O-FeOOH and P-FeOOH/Fe3O4 mixtures reacted differently during washing. Pure 0-FeOOH completely transformed to cc-FeOOH in the alkaline environments provided by NaOH and NaOH/Na2SO3. This released all the chloride from the PFeOOH. In NaOH solutions within the range pH8.5 to 10.5 0-FeOOH/Fe3O4 transformed mostly to Fe304. Above pH1 1 there was limited conversion. Improved release of Cl' from P-FeOOII/Fe3O4 mixture correlated with the transformation of PFeOOH to Fe304.

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Akharame, Michael Ovbare. "Novel β-feooh/polymeric composites for remediation of wastewaters." Thesis, Cape Peninsula University of Technology, 2020. http://hdl.handle.net/20.500.11838/3110.

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Thesis (DPhil (Chemistry))--Cape Peninsula University of Technology, 2020
Water reclamation and sustainability through nano-based treatment processes has a promising prospect. The safe application of the numerous nanomaterials being applied for water treatment purposes is of utmost importance in this new phase of nanotechnology deployment. This is pertinent due to their potential adverse environmental and health concerns. This study was designed to investigate the suitability of polyamide matrix as immobilization support for the established catalyst- β-FeOOH nanoparticles. The synthesized polymeric nanocomposites (PNCs) were utilized for the remediation of 4-chlorophenol (4CP) and 4-nitrophenol (4NP). The analytes were selected to investigate the role of the attached groups (chloro- and nitro-) in the degradation intermediates, pathways and kinetics using the liquid chromatography/mass spectrometry time-of-flight (LCMS-TOF) instrumentation. The hydrothermally synthesized β-FeOOH nanoparticles and the PNCs fabricated via the in situ route were characterized using attenuated total reflectance-Fourier transform infrared (ATR-FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and nitrogen adsorption-desorption (Brunauer-Emmet-Teller and Barrett-Joyner-Halenda), which confirmed the clear-phase β-FeOOH nanoparticles and its successful incorporation into the polyamide matrix. Daphnia magna acute toxicity test was done to establish the safe application of the polymeric nanocomposites and the optimum treatment duration for the wastewater. The ozonation of the analytes solution (100 mL of 2 x 10-3 M) was done in a sintered glass reactor, with samples collected at different intervals over 60 min. The comparative oxidation results revealed that the 4-chloro- and 4-nitrocatechol pathways via hydroxylation were the major degradation route for 4CP and 4NP. Catechol intermediate was present as a primary breakdown product for the two analytes. Hydroquinone was observed as the transient degradation intermediate for 4CP but was absent for 4NP. Rather, an ozonation intermediate 2, 4-dinitrophenol was identified which was further oxidized to 3,6-dinitrocatechol. Several dimer products (C12H8Cl2O2, C12H8Cl2O3, C12H8Cl2O4, C12H8N2O6, C12H8N2O7, etc.) were identified in the oxidation processes, favoured by alkaline conditions with more versatility shown by 4CP. Catalytic properties of the β-FeOOH/polyamide nanocomposites were evaluated during the degradation of 4CP and 4NP aqueous solutions through catalytic ozonation processes. The catalysed ozonation results showed 98.52% and 89.66% degradation of 4CP and 4NP using the optimum performing catalyst (1.25 wt% β-FeOOH loading) within 40 min relative to 62.94% and 55.21% degradation for the simple ozonation, respectively. The effect of pH on the degradation efficiency revealed that the catalysed ozonation is more favourable at higher pH values (pH 10 > 7 > 3). The COD and TOC values for real wastewater was effectively reduced by 54.62% and 89.22% by the polymeric nanocomposites compared to 33.92% and 47.06% removal obtained in the uncatalysed ozonation. The involvement of hydroxyl radicals in the breakdown of the phenols was confirmed by using methanol as a scavenger, which reduced the degradation efficiency of 4CP from 98.52% to 25.64% when it was added to the analyte solution. The composite exhibited excellent reuse potential with minimal decrease in its degradation ability over six cycles, and no leaching of iron was observed when applied in acidic, neutral and alkaline conditions. The complete degradation of 4CP after the treatment of the contaminated water for 1 h was established using the LCMS-TOF. However, the toxicity results showed that the treated water obtained at 1.5 h had better quality. Toxic intermediates persist in solution even though the parent analyte was completely degraded. Hence, toxicity assays should be encouraged on a complementary basis to the standard chemical methods. The study provided a great insight into the ozone degradation intermediates and pathways of 4CP and 4NP. The novel polymeric nanocomposites gave promising remediation ability for the removal of 4CP and 4NP from aqueous solutions and provided a safe deployment of the catalyst utilized.

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Ding, Xiangbin. "Identity of Fluoride and Phosphate-Binding Sites at FeOOH Surfaces." Thesis, Umeå universitet, Kemiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-56738.

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Iron oxyhydroxides are of widespread occurrence in nature and play essential roles in both environmental as well as industrial processes. Due to their high reactivity, these minerals can act as sinks and/or transformation centers for a variety of inorganic and organic ions. These reactions are often mediated by various surface hydroxyl groups that are in turn singly-, doubly- or triply-coordinated with respect to underlying Fe atoms. In an effort to follow the reactivity of these different groups, attenuated total reflectance (ATR) - Fourier transform infrared (FTIR) spectroscopy was used to monitor adsorption reactions of on iron oxyhydroxide minerals. This work was specifically focused on synthetic submicron-sized lepidocrocite and goethite particles reacted to aqueous solutions of sodium fluoride and sodium phosphate. Langmuir-Freundlich adsorption isotherms were calibrated on adsorption data at various pH values to provide independent clues to the maximum sorption density achieved by these ions. When compared to theoretical site densities, these values suggested that although singly-coordinated groups are by far the more reactive groups on all surfaces, doubly-coordinated groups could be substituted by fluoride ions. FTIR measurements of dry mineral samples equilibrated with fluoride and phosphate confirmed these findings and also showed that triply-coordinated groups cannot be exchanged. Key words : goethite, lepidocrocite, FTIR, surface, adsorption, isotherm, modeling

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17

Chowdhury, Mahabubur Rahman. "Solvent dependent growth of one-dimensional crystalline ß-FeOOH nanorods." Thesis, Cape Peninsula University of Technology, 2014. http://hdl.handle.net/20.500.11838/928.

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Thesis submitted in fulfilment of the requirements for the degree DOCTOR TECHNOLOGIAE: ENGINEERING: CHEMICAL in the FACULTY OF ENGINEERING at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY 2014
Several authors have reported on the use of alcohols – water /or mixed solvents to synthesise metal oxide nanoparticles. However, no systematic study has been carried out to evaluate the effect of mixed solvent on the particle characteristics, although considerable research has been reported, a gap still exists with regard to the effect of the alcohols as solvents on the growth kinetics of nanoparticles. To address these issues, four different alcohols, namely, methanol (MeOH), ethanol (EtOH), propanol (PrOH) and butanol (BuOH) were used as solvents in the synthesis of β-FeOOH particles. The effect of organic solvents on the growth kinetics of β-FeOOH nanorods has been evaluated for the first time in this study. Two-stage growth of akaganeite nanorods has been observed in BuOH and PrOH. The first growth stage follows a typical power law representing Ostwald ripening (OR) kinetic. The second stage was found to be asymptotic and obeyed oriented attachment (OA) kinetic. The proof of the OA kinetic also comes from the HRTEM images of the synthesised particles. Simultaneous occurrence of the two mechanisms was observed in the growth of the particles synthesised in EtOH and MeOH. The rate constants for OR kinetic, KOR, was found to be higher than the rate constant for OA kinetic, KOA, for different solvents used. Preamble The use of a mixed solvent is a new approach in the synthesis and processing of materials. Various researchers have stated that the surface tension of the solvent plays an important role in the formation of uniform nanorods. However, the effect of surface tension was not correlated with the particle growth, earlier, though the dielectric properties of the mixed solvents were only taken into account. Additionally, no quantitative or qualitative relationship was presented between surface tension and particle growth in the literature. In this work an attempt to correlate these two parameters (surface tension and particle growth) with the concentration of the precursor and temperature was made, resulting in an exponential relationship between KOR for the particle growth and surface tension of the alcohols. Furthermore, the relationship between surface tension and particle growth was validated by an independent study using statistically designed experiments to account for the influence of various process variables on the particle growth. The findings in this study obtained from both theoretical and experimental work provides an insight into the relationship between solvent surface tension and particle growth interactions, producing a new piece of information that will further promote our understanding of the formation mechanisms of β- FeOOH growth. The transformation temperature of akaganeite (β-FeOOH) nanorods to hematite (α-Fe2O3) particles was found to be solvent dependent. Thermogravimetric analysis and differential scanning calorimetry were performed to evaluate the effect of alcohol on the thermodynamic stability of the particles. Alcohol as solvent played a significant role in the dehydration property of the synthesised particles. The percentage mass loss of the particles at 300°C decreases linearly with increasing carbon number in the linear alkyl chain of the solvent. The effect of alcohol type on the particle morphology was found to be more pronounced at higher FeCl3 concentrations (>0.5M). Splitting of β-FeOOH nanorods was observed at FeCl3 concentration of 0.7M in BuOH. In PrOH, rectangular morphologies were obtained whereas nanoribbons resulted in surfactant-free conditions. It was found that the nature of anions (chloride vs. nitrate and sulphate) in the precursor salt also influenced the morphology.

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18

Spadini, Lorenzo. "Struktur und Stabilität von Oberflächenkomplexen im System Cd2[plus]-FeOOH /." [S.l.] : [s.n.], 1996. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.

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19

Lenz, Lea Feodora [Verfasser], Ansgar [Akademischer Betreuer] Reiners, Ansgar [Gutachter] Reiners, and Stefan [Gutachter] Dreizler. "Star-Planet Interactions: Emission Spectroscopy of H3+ in Extrasolar Giant Planet Atmospheres / Lea Feodora Lenz ; Gutachter: Ansgar Reiners, Stefan Dreizler ; Betreuer: Ansgar Reiners." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1193728401/34.

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20

Neher, Margret Feodora Maria [Verfasser], Lucia [Akademischer Betreuer] Tabares, Jochen [Akademischer Betreuer] Weishaupt, Silvio [Akademischer Betreuer] Rizzoli, and Margarete [Akademischer Betreuer] Schön. "Synaptic Vesicles, Mitochondria, and Actin Alterations in SMN-deficient Mice / Margret Feodora Maria Neher. Gutachter: Jochen Weishaupt ; Silvio Rizzoli ; Margarete Schön. Betreuer: Lucia Tabares." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://d-nb.info/1071991604/34.

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21

Wijenayaka, A. K. Lahiru Anuradha. "Investigation of the atmospheric processing of α-FeOOH containing aerosols with water and HNO3: reactivity, fate, and consequences and the impact of particle size on surface adsorption and particle solubility." Thesis, University of Iowa, 2011. https://ir.uiowa.edu/etd/2789.

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The atmosphere is a heterogeneous system which is rich in potential chemistry. The processes taking place within this system as well as at the interface of its constituents are of immense importance in understanding how the atmosphere in turn can impact the well-being of all living on the surface of earth. Thus, the heterogeneous chemistry of atmospheric aerosols has since long been subjected to extensive scientific investigation, in view of broadening our understanding of this imperative system. In this study, the heterogeneous interactions of water vapor and gaseous HNO3 on goethite (a-FeOOH), a prominent component of mineral dust aerosol is investigated with quartz crystal microbalance (QCM) measurements and attenuated total reflectance - Fourier transform IR (ATR-FTIR) spectroscopy. Laboratory synthesized goethite samples of varying size (microrods of specific surface area 34 m2/g and nanorods of specific surface area 121 m2/g) were used in order to identify the size dependent interaction of goethite with H2O and HNO3. The study revealed that the exposure of goethite to gas phase H2O and HNO3 results in the uptake of these gases via surface adsorption. Additionally, this novel combined approach of QCM and ATR-FTIR spectroscopy allowed for quantification of the amount of uptake while the spectroscopic data provided information on the speciation of adsorbed products. Thus, with the QCM and spectroscopic data in hand, a precise interpretation of the reactivity as well as its size dependence was sought. In a general sense, the reactivity of a substance is believed to increase with decreasing particle size. The results of this investigation show that in the case of H2O, both microrods and nanorods take up water while the total amount of adsorbed water, when normalized to surface area, is similar for both particle sizes. However, for HNO3, the saturation coverage of total and irreversibly bound HNO3 on microrods was observed to be higher than that on nanorods. With supplementary analysis, this anomalous size effect was attributed to structural features such as the involvement of surface hydroxyl groups in determining the reactivity, which would be subjected to change as a function of particle size. Furthermore, an investigation of the behavior of HNO3 reacted goethite in aqueous media and the uptake of H2O and HNO3 at their mutual presence was carried out such as to better understand the effects of atmospheric processing upon dispersal within the hydrosphere. Further analysis is warranted before arriving at a general conclusion on the size-dependent reactivity of goethite. However, we may argue that goethite containing aerosols may indicate the same pattern of reactivity within the atmosphere as that observed here. Thus, the inference of this investigation proves to be significant in broadening our understanding of this atmosphere as well as the entire biosphere as a whole.

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Araújo, Moisés Albuquerque de. "Síntese, caracterização e estudo das propriedades fotoeletrocatalíticas dos fotoanodos BiVO4 e BiVO4/FeOOH." Universidade Federal de São Carlos, 2015. https://repositorio.ufscar.br/handle/ufscar/7833.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Among the variety of semiconductor materials investigated to apply in electrochemical cells bismuth vanadate (BiVO4) is one of the candidate which would be used as photoanode. Thus, this study aimed to synthesize thin films of BiVO4 and their modification with a thin layer of iron (III) oxyhydroxide (FeOOH) by photodeposition and study their photoelectrocatalytic properties. The optimization of BiVO4 synthesis condition was assessed by a factorial design 23 and an analysis of univariate type. The parameters studied were annealing temperature (500 and 600 °C), calcinations time (30, 60, 150 and 270 min.), solvent type employed for dissolving the BiVO4 precursor reagents (poly ethylene glycol 300-PEG 300, PEG 400, ethylene glycol-EG, mixture 1:1 by volume of PEG 300 and EG), deposition method of BiVO4 films (dropping and spin coating) and method of drying layers (heating at 500 °C, heat gun and no drying). From the optimized condition BiVO4 film was prepared by dissolving bismuth (III) nitrate and ammonium metavanadate in a mixture of 1:1 by volume of EG and PEG 300, it was deposited onto glass containing FTO by spin coating and then calcinated directly at 500 °C for 60 min. The photodeposition was carried out in the mixture FeSO4 and sodium citrate medium both 1 mmol L-1 and pH 4.7 by applying the open circuit potential for 5 min. and under light incidence. and then polarizing at 1.2 V for 1 min. BiVO4 and BiVO4/FeOOH films were characterized by XRD, SEM, EDS, UV-vis, voltammetry (cyclic and linear) and electrochemical impedance spectroscopy. The results reveled that photocurrent values increased 2.5 times at 0.71 V and the on set potential shifted to less positive value in the presence of FeOOH, also there was a considerable reduction of the charge transfer resistance in the interface photoanode/solution. The bare BiVO4 films were photostable during the illumination time studied which was 4 h. However, the modified films did not show the same behavior, the photocurrent value decreased 29% after 4 h illuminated. The results in the sulphite presence showed that photocurrent value for bare BiVO4 and BiVO4/FeOOH were less than the maximum photocurrent value which would achieve for this materias.
Dentre os diversos materiais semicondutores estudados para aplicação em células fotoeletroquímicas encontra-se o vanadato de bismuto (BiVO4), o qual pode ser utilizado como fotoanodo. Deste modo, o presente trabalho teve como objetivo principal a síntese de filmes finos de BiVO4 e sua modificação com uma fina camada de oxihidróxido de ferro (III) (FeOOH) por fotodeposição e avaliação das propriedades fotoeletrocatalíticas destes materiais. A otimização das condições de síntese do BiVO4 foi avaliada por um planejamento fatorial 23 e por uma análise do tipo univariada. Os parâmetros estudados foram temperatura de calcinação (500 e 600 °C), tempo de calcinação (30, 60, 150 e 270 min.), tipo de solvente empregado para dissolução dos reagentes precursores do BiVO4 (polietileno glicol 300-PEG 300, PEG 400, etileno glicol-EG, mistura 1:1 em volume de PEG 300 e EG), método de deposição dos filmes de BiVO4 (dropping e spin coating) e método de secagem das camadas dos filmes (aquecimento a 500 °C, soprador térmico e sem secar). Nas condições otimizadas o filme de BiVO4 foi preparado pela dissolução de nitrato de bismuto (III) e metavanadato de amônio em uma mistura de 1:1 em volume de EG e PEG 300, depositado sobre vidro contendo FTO por spin coating e depois calcinado diretamente a 500 ºC por 60 min. A fotodeposição foi realizada em meio da mistura FeSO4 e citrato de sódio ambos a 1 mmol L-1 e pH 4,7, aplicando-se o potencial de circuito aberto por 5 min. e com incidência de luz, seguida de polarização em 1,2 V por 1 min. Os filmes de BiVO4 e BiVO4/FeOOH foram caracterizados por DRX, MEV, EDX, UV-vis, voltametria (cíclica e linear) e espectroscopia de impedância eletroquímica. Os resultados mostram que na presença do FeOOH houve aumento de 2,5 vezes nos valores de densidade fotocorrente em 0,71 V e o potencial de on set deslocou-se para valores menos positivos, bem como uma redução considerável na resistência de transferência de carga na interface fotoanodo/solução. Os filmes de BiVO4 puro apresentaram-se fotoestáveis durante o tempo de iluminação estudado, 4 h. No entanto, os filmes modificados não apresentaram o mesmo comportamento, houve um decréscimo de 29% no valor de densidade de fotocorrente após 4 h de iluminação. O estudo na presença do sulfito mostrou que os valores de fotocorrentes para o BiVO4 puro e o BiVO4/FeOOH estão abaixo do valor máximo que se poderia obter para estes materiais.

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Netto, Silvania Maria. "Caracterização cristaloquimica da incorporação de ions cobre (II) em Goethita (alfa-FeOOH) sintetica." [s.n.], 2001. http://repositorio.unicamp.br/jspui/handle/REPOSIP/286792.

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Orientadores : Jacinta Enzweiler, Maria Luiza Melchert de Carvalho e Silva
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociencias
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Doutorado

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Feodoria, Mark-Roman [Verfasser]. "Optimal investment and utility indifference pricing in the presence of small fixed transaction costs / Mark-Roman Feodoria." Kiel : Universitätsbibliothek Kiel, 2016. http://d-nb.info/1118499948/34.

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25

Larrea, Juan José. "Peuplement et societe en navarre de la fin du monde romain a l'age feodal (quatrieme - douzieme siecles)." Toulouse 2, 1994. http://www.theses.fr/1994TOU20022.

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Ce travail etudie la formation du feodalisme dans le royaume de pampelune - puis de navarre- et les liens entre evolution sociale et peuplement rural. Il prend comme point de repere historiographique les theses regionales sur la catalogne ou le latium par exemple. Les sources ecrites, narratives et surtout diplomatiques, consistuent la base du travail, mais les donnees archeologiques, toponymiques, voire onomastiques jouent aussi un role considerable. La these comprend quatre parties : 1) on remonte le temps jusqu'au bas-empire afin de discerner le mode d'occupation des campagnes pendant les cinquimee-huitieme siecles et de caracteriser la societe dont on veut etudier l'evolution vers le feodalisme. Contrairement aux idees generalement admises, on montre une vasconie dont les structures ne different pas sensiblement de celles de tout l'occident tardoromain. 2) la societe navarraise des neuvieme-dixieme et debut du onzieme siecles est analysee sur cinq plans : croissance agricole et peuplement, monarchie et aristocratie, structures de gouvernement public, problemes de la grande propriete et vigueur de l'alleu et de la liberte paysannes. 3) on examine la crise qui secoue, pendant les decennies centrales du onzieme siecle, l'organisation sociale heritee du haut moyen age : ebranlement de la structure de pouvoir traditionnelle et debut de l'encadrement feodal de l'aristocratie, instauration de la seigneurie banale, et configuration du groupe des milites. Il s'agit d'un bouleversement profond, mais qui se deroule sous l'apparence de la continuite de l'ancienne souverainete publique. 4) on finit par donner une image de la societe feodale navarraise jusqu'au milieu du douzieme siecle. On s'interesse a l'evolution de la condition paysanne et on prete une attention speciale aux differences entre la structure seigneuriale de la vieille navarre et celle du bas pays-conquis sur les musulmans et colonise a partir du milieu du
This dissertation studies the formation of feudalism in the kingdom of pamplona - later on navarre- and the relationship between social evolution and rural settlement. The regional theses about catalonia and the latium for example are taken as historiographic reference. The narrative and especially diplomatic written sources constitute the m basis for this work, although archaelogical, toponymic, and even onomastic data are also important. The dissertation includes four parts : 1) it goes back in time until the late empire, so that a close look at the rural settlement along fifth-eight centuries can be taken, and the society whose evolution towards feudalism is to be studied can be characterised. Contrary to the ideas generally taken for granted, we see a vasconia which shares the essential features late roman western europe. 2) the navarrese society of the ninth, tenth and beginning of eleventh centuries is analysed from five points of view : agricultural growth and settlement, monarchy and aristocracy, structures of public government problems of the great property, and vigour of the peasant little allodial property and freedom. 3) the crisis that shake social organisation inherited from the early middle ages during the central decades of the eleventh century is looked at fall of the traditional power structure and beginning of the feudal organization of aristocracy, installation of the sei banale and shaping of the group of milites. It is a deep upheaval which nevertheless developed under the apparent continuity of the ancient public sovereignty. 4) finally an image of the navarrese feudal society until mid twelfth cent is given. This part focuses on the evolution of the peasant state, and especially on the differences between the seigneu structure of the ancient navarre and that of the southern territory -conquered from the muslims and colonized from mid eleventh century on-, and also on the consequences of those differences as far as settlement patterns are concerned. The breaking-up of the lordship authority in ancient navarre brings about the fossilization of the net of little settlements

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26

LEMAIRE, Bruno. "Propriétés structurales et magnétiques d'un cristal liquide minéral, les suspensions de goethite (alpha-FeOOH)." Phd thesis, Université Paris Sud - Paris XI, 2002. http://tel.archives-ouvertes.fr/tel-00002172.

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Notre travail a porté sur différents cristaux liquides minéraux, et principalement sur les suspensions aqueuses de goethite. Après les avoir caractérisées, nous avons démontré qu'elles forment une phase nématique, et décrit la transition isotrope-nématique grâce aux modèles de la littérature. La phase isotrope présente trois propriétés originales sous champ magnétique : un ordre paranématique très élevé, une composante dipolaire de l'ordre orientationnel non nulle et le changement d'orientation de la phase suivant la valeur du champ (parallèle à un champ statique faible, mais perpendiculaire à un champ fort). Nous avons déterminé le paramètre d'ordre nématique par des mesures de biréfringence ainsi que par diffusion des rayons X aux petits angles, et le paramètre d'ordre dipolaire par des mesures d'aimantation. Nous avons interprété et modélisé le changement d'orientation comme la compétition entre un moment magnétique longitudinal indépendant du champ (probablement dû à des spins non compensés en surface), et le moment magnétique induit par le champ (anisotropie magnétique négative). Le premier domine à champ faible, le second à champ fort. Sous ces hypothèses, l'orientation est toujours perpendiculaire sous un champ de fréquence élevée, ce que nous avons observé. Le modèle donne des résultats en accord avec les mesures. Puis nous avons étudié les propriétés de la phase nématique sous champ magnétique. Le seuil de Frederiks est très bas, et l'ordre nématique extrêmement élevé. Les particules basculent perpendiculairement au champ magnétique lorsqu'il croît, par une seconde transition de Frederiks, formant un domaine nématique biaxe. A champ encore plus élevé se forme un cristal colloïdal bidimensionnel de groupe d'espace c2mm. On observe la même phase en champ nul à forte concentration. Enfin, nous incluons nos publications, sur les suspensions de goethite, de plans covalents rigides de H3Sb3P2O14, de polymères flexibles de NaNb2PS10 et de plaquettes de laponite.

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27

Lemaire, Bruno. "Propriétés structurales et magnétiques d'un cristal liquide minéral, les suspensions de gœthite (α-FeOOH)." Paris 11, 2002. http://www.theses.fr/2002PA112120.

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Notre travail a porté sur différents cristaux liquides minéraux, et principalement sur les suspensions aqueuses de goethite. Après les avoir caractérisées, nous avons démontré qu'elles forment une phase nématique, et décrit la transition isotrope-nématique grâce aux modèles de la littérature. La phase isotrope présente trois propriétés originales sous champ magnétique : un ordre paranématique très élevé, une composante dipolaire de l'ordre orientationnel non nulle et le changement d'orientation de la phase suivant la valeur du champ (parallèle à un champ statique faible, mais perpendiculaire à un champ fort). Nous avons déterminé le paramètre d'ordre nématique par des mesures de biréfringence ainsi que par diffusion des rayons X aux petits angles, et le paramètre d'ordre dipolaire par des mesures d'aimantation. Nous avons interprété et modélisé le changement d'orientation comme la compétition entre un moment magnétique longitudinal indépendant du champ (probablement dû à des spins non compensés en surface), et le moment magnétique induit par le champ (anisotropie magnétique négative). Le premier domine à champ faible, le second à champ fort. Sous ces hypothèses, l'orientation est toujours perpendiculaire sous un champ de fréquence élevée, ce que nous avons observé. Le modèle donne des résultats en accord avec les mesures. Puis nous avons étudié les propriétés de la phase nématique sous champ magnétique. Le seuil de Frederiks est très bas, et l'ordre nématique extrêmement élevé. Les particules basculent perpendiculairement au champ magnétique lorsqu'il croit, par une seconde transition de Frederiks, formant un domaine nématique biaxe. A champ encore plus élevé se forme un cristal colloi͏̈dal bidimensionnel de groupe d'espace c2mm. On observe la même phase en champ nul à forte concentration. Enfin, nous incluons nos publications, sur les suspensions de goethite, de plans covalents rigides de H(3)Sb(3)P(2)O(14), de polymères flexibles de NaNb(2)PS(10) et de plaquettes de laponite
We carried experiments on different mineral liquid crystals and especially on suspensions of colloidal goethite particles. After characterizing the suspensions, we showed that they form a nematic phase. We described the isotropic nematic phase transition with the models of literature. Three properties of the isotropic phase under magnetic field are : a very high paranematic order, a non vanishing dipolar component of the orientation order and the change in orientation with the value of the field (parallel to a low field, perpendicular to a high one). We determined the nematic order parameter by birefringence and small angle X-ray scattering measurements, and the dipolar one by magnetization measurements. We interpreted the change in orientation as the competition between a longitudinal field-independent magnetic moment (probably uncompensated spins at the surface of the particles) and the induced magnetic moment (negative magnetic anisotropy). The former dominates at low fields and the latter at higher ones. In this frame, the orientation must remain perpendicular to a high-frequency field, which we observed experimentally. The model fitted the experimental data well. Then we studied the properties of the nematic phase under field. The Fredenks transition threshold is outstandingly low, while the nematic order is very high. The particles reorient perpendicular to a higher field, through a second Frederiks transition, forming a nematic biaxial domain. At even higher fields, the suspension forms a two-dimension colloidal crystal in the c2mm space group. The same phase occurs in zero field at high concentrations. Finally, we include our published articles, concerning suspensions of goethite, stiff covalent sheets of H(3)Sb(3)P(2)O(14), flexible polymers of NaNb(2)PS(10) and laponite disc-like moieties

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28

Lumsdon, David G. "A study of arsenate adsorption on goethite (α-FeOOH) in relation to selected ions." Thesis, University of Aberdeen, 1986. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=215999.

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Infrared spectroscopy was used to show that the arsenate anion is adsorbed on the surface of synthetically prepared goethite, replacing two singly coordinated (A-type) surface OH groups. In this respect, arsenate is analogous to phosphate, but its larger size causes it to interact more strongly with other OH groups that remain on the surface. This has suggested an alternative infrared band assignment for these OG groups. Potentiometric titrations performed on 'CO₂'-free goethite gave a value for the point of zero charge (p.z.c.) of 9.15. The p.z.c. shifted to more acid values for phosphate- and arsenate-treated goethite indicating an increased negative surface charge. For sulphate-treated goethite the positive surface charge increased slightly. The results were interpreted as indicating that phosphate and arsenate were adsorbed by a chemisorption (ligand-exchange) mechanism. The exact nature of the sulphate interaction was still unclear. Solution studies on the goethite-aqueous solution interface demonstrated the adsorption of arsenate by a binuclear bridging mechanism, confirming the findings from the infrared study. The results indicated a 2:1 stoichiometry between ligands exchanged and arsenate adsorbed over the pH range 4-10. No such stoichiometry was observed for sulphate adsorption though the reaction between sulphate and goethite consumed protons (i.e. released hydroxyl). A brief study to ascertain the effect of certain competitors on arsenate adsorption was performed. Results showed considerable reduction in arsenate adsorption when vanadate ions were added simultaneously with arsenate to goethite-aqueous electrolyte suspensions. The results also indicated that goethite previously coated with small quantities of humic acid reduced arsenate adsorption. The presence of sulphate in solution at up to five times the concentration of arsenate had no effect on arsenate adsorption over the pH range 5 to 9.

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Han, Ruixin. "SYNTHESIS, AND STRUCTURAL, ELECTROCHEMICAL, AND MAGNETIC PROPERTY CHARACTERIZATION OF PROMISING ELECTRODE MATERIALS FOR LITHIUM-ION BATTERIES AND SODIUM-ION BATTERIES." UKnowledge, 2018. https://uknowledge.uky.edu/chemistry_etds/90.

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Iron oxides, have been widely studied as promising anode materials in lithium-ion batteries (LIBs) for their high capacity (≈ 1000 mA h g-1 for Fe2O3 and Fe3O4,), non-toxicity, and low cost. In this work, β-FeOOH has been evaluated within a LIB half-cell showing an excellent capacity of ≈ 1500 mA h g-1 , superior to Fe2O3 or Fe3O4. Reaction mechanism has been proposed with the assistance of X-ray photoelectron spectroscopy (XPS). Various magnetic properties have been suggested for β-FeOOH such as superparamagnetism, antiferromagnetism and complex magnetism, for which, size of the material is believed to play a critical role. Here, we present a size-controlled synthesis of β-FeOOH nanorods. Co-existing superparamagnetism and antiferromagnetism have been revealed in β-FeOOH by using a Physical Property Measurement System (PPMS). Compared with the high price of lithium in LIBs, sodium-ion batteries (SIBs) have attracted increasing attentions for lower cost. Recent studies have reported Na0.44MnO2 to be a promising candidate for cathode material of SIBs. This thesis has approached a novel solid-state synthesis of Na0.44MnO2 whiskers and a nano-scaled open cell for in situ TEM study. Preliminary results show the first-stage fabrication of the cell on a biasing protochip.

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Murad, T. M. A. "Investigation into hydrogen bonding configurations in metal oxide hydroxides, with special reference to gamma-FeOOH." Thesis, Swansea University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638279.

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Ntiribinyange, Mary Solange. "Degradation of textile wastewater using ultra-small Β-Feooh/Tio2 heterojunction structure as a visible light photocatalyst." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2467.

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Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2016.
The worldwide high demand for drinking water has led to the development of numerous advanced wastewater treatment processes. Photocatalysis has recently become an alternative and attractive technique for green energy production and environmental remediation. It is also a wastewater treatment technique which is considered reliable and is expected to provide a sustainable solution to the scarcity of clean water. In particular, heterogeneous photocatalysts based on TiO2 nanoparticles and sunlight have been proposed as a powerful technique for degradation and mineralisation of persistent organic pollutants (POP`s). Although this method seems promising, some critical challenges are still to be addressed: namely, low photoefficiencies, faster electron and hole (𝑒−⁄ℎ+) pair recombination, utilisation of UV light and catalyst removal after treatment of pollutants.

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Parsons, Christopher. "Distribution et mobilité de l'arsenic dans les sols : effets de cycles redox successifs." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00637484.

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L'arsenic est un metalloïde toxique et cancérigène. Ubiquiste dans la pedosphere, il est très sensibleaux fluctuations des conditions redox du sol, ce qui influe significativement sa toxicité et mobilité. Nousétudions le cycle biogéochimique global de l'arsenic, en tenant compte de l'usage croissant des ressources, etpassons en revue l'importance respective de l'arsenic geogénique et anthropogénique dans l'environnement.La contamination à l'arsenic est souvent diffuse dans les bassins sédimentaires de l'Europe. Cependant, desconcentrations dans l'eau interstitielle du sol peuvent être élevées lors de périodes de saturation du solcausées par la monté des eaux souterraines ou les inondations, prévues d'augmenter dû aux changementsclimatiques. La spectrométrie de fluorescence X quantitative et sans standard a été utilisée pour analyserl'arsenic dans des sols relativement contaminés de la plaine alluviale de la Saône au moyen de protocoles depréparation d'échantillons conçus pour optimiser la précision d'analyse et l'exactitude in situ aux bassesconcentrations d'arsenic. L'arsenic dans ces sols est associe aux (hydr)oxydes du fer et de manganèse de lataille d'argile colloïdale. Ceux-ci subissent une dissolution réductrice par les microorganismes lors desinondations, libérant une importante concentration d'arsenic dans la phase aqueuse. Si, par la suite, l'arsenicdégagé n'est pas éliminé avec l'eau de crue évacuée, il est ré-immobilisé pendant l'oxydation du sol et lareprécipitation des oxydes métalliques. Grâce à une combinaison novatrice d'analyses chimiques par voiehumide, d'écologie microbienne, de spectroscopie ainsi que de modélisation thermodynamique et cinétique,nous démontrons que les cycles d'oxydo-réduction séquentiels entraînent une atténuation d'arsenic aqueuxdans des conditions réductrices dû à la coprécipitation croissante, et a une diminution de l'activitémicrobienne causée par l'appauvrissement en matière organique labile. Des processus d'atténuationsimilaires sont observés en l'absence d'activité microbienne pour Cr et As dans des argiles pyriteuses lorsquecelles-ci sont exposés aux oscillations redox provoquées par l'ajout de substances humiques réduites. Ainsi,nous montrons que les effets cumulatifs de cycles redox successifs sont extrêmement importants pour lamobilité de divers contaminants dans l'environnement.

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Ståhlberg, Andreas. "Frälsesamhället : En studie av det svenska 1300-talsfrälsets ideologi såsom framställd i Erikskrönikan." Thesis, Karlstads universitet, Avdelningen för politiska och historiska studier, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-16324.

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In the wake of a heightened interest in the Swedish Middle Ages, the need for knowledge has increased as well. The Swedish Middle Ages was an era when the country truly began to grow closer to the European sphere of culture. The forces behind this transformation are largely to be sought among the social elite, the budding aristocracy of Sweden. The process of becoming “Europeans” brought with it great changes to Sweden, not the least in terms of the political arena. What was it that was so sought after by the Swedish aristocracy? What ideals and values lay behind the feudally inspired system of government and the chivalric code of conduct among the elite? In a general sense, the object of this investigation has been to try to understand and explore the ideological underpinnings of the new system of government and the new social order. In order to achieve this, I have used the Swedish chivalric chronicle known as Erikskrönikan as the source material for the investigation. It is believed to have been a propaganda piece for the Swedish aristocracy of the early 1300 hundreds and is, as such, a phenomenal source for researching the ideals and values of the Swedish aristocracy of that time. Thus, the purpose of this essay has been to investigate ideological underpinnings of the Swedish power elite of the first half of the 14th century by analysing their idealized self image and conception of society, as they appear in Erikskrönikan’s depiction of duke Erik and a few other key characters. Included in this is also an ambition to contextualize the results of the investigation by attempting to reconstruct the ideology for which Erikskrönikan is an expression. The intention has been to contribute a new perspective to the already extant research concerning the understanding of the new type of society brought forth in medieval Sweden. The theoretical premise of this investigation has been a functional understanding of the concept of ideology. In this essay ideology is regarded as a system of ideas which expresses a given groups world views and norms, which reflects the social conditions of the group, and which is a declaration of that group’s interests and aspirations. The methodological basis has been a qualitative analysis of the text, where the depiction of selected characters from the text has been the main object of investigation. The focus has been on identifying which characteristics are portrayed as ideal and which are portrayed as are anti ideal within the text. On an analytical level this investigation has included the use of the concepts “manifest ideology” and “latent ideology” as tools of analysis. In this way it has been possible to uncover the ideals and values of the aristocracy, as expressed in Erikskrönikan, both in terms of what is articulated explicitly and what is implied. In terms of results this investigation has rendered them in abundance. Among the most revealing and relevant findings are: the emphasis put on the vassal system, the chivalrous virtues and the staunch declaration about the superiority of elective kingship. These are all examples of recurring themes which are communicated with a clear didactic intent. Furthermore, I have also been able to show that the code of chivalry was not considered a varnish to cover the blemishes of an imperfect society, but a way of relating to reality and to the surrounding world. The tangible functions of the code of chivalry in society can be understood as having been of two kinds: on the one hand, the code of chivalry was a way of reigning in and channelling the destructive potential of the use of violence; and on the other hand, the code of chivalry was a way for the aristocracy, indeed the Swedish chivalry, to communicate and reaffirm their social standing, both internally and externally.

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Arreola, Leyva Jesús Enrique. "Adsorción de Pb(II) presente en Solución Acuosa sobre los Oxihidróxidos: Beehmita (AIOOH), GOETITA (FeOOH)y Manganita (MnOOH)." Tesis de Licenciatura, Medicina-Quimica, 2013. http://ri.uaemex.mx/handle/123456789/13931.

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La boehmita, goetita y manganita fueron sintetizadas por diferentes métodos y caracterizadas mediante difracción de rayos X (DRX), espectroscopía infrarroja (IR), estudio termogravimétrico (TGA-DSC), mediciones de fisisorción de N2, microscopía electrónica de barrido (MEB), análisis elemental semicuantitativo (EDS), además como estudios complementarios se determinó la concentración de sitios activos superficiales y del punto de carga cero (zpc) por sus sigla en inglés. Por otro lado, se estudió la capacidad de adsorción de los iones Pb(II) presentes en solución acuosa sobre estos materiales mediante experimentos tipo lote a temperatura ambiente, como una función del tiempo de contacto entre las fases del sistema sólido-líquido (cinética de adsorción), concentración inicial del adsorbato (isotermas de adsorción), pH y temperatura. Se encontró que el equilibrio de los procesos de adsorción en los sistemas estudiados se logró a 60 minutos para la boehmita y a 30 minutos para la goetita y manganita respectivamente después de poner en contacto las fases sólido-líquido de los sistemas. La capacidad de adsorción de los iones plomo sobre estos materiales adsorbentes dependió de la concentración del plomo, del pH y de la temperatura de los sistemas. Se evaluaron sus capacidades de adsorción de plomo en estos materiales a diferentes tiempos de contacto usando una concentración inicial de 20 mg/L de iones Pb(II) a pH = 4, los resultados de los tres sistemas se ajustaron al modelo cinético de pseudo segundo orden. Con respecto a los estudio del efecto de la concentración del adsobato, los sistemas bohemita-Pb(II) y goetitaPb(II) se ajustaron al modelo de isoterma de Langmuir, el cual propone que la adsorción se lleva a cabo en una monocapa, por otra parte el sistema manganitaPb(II) se ajustó al modelo de isoterma de Tempkin, el cual asume que el calor de adsorción de todas las moléculas en la capa disminuye linealmente con la cobertura debido a las interacciones adsorbente-adsorbato, y que la adsorción se caracteriza por una distribución uniforme de las energías de enlace. Al estudiar el efecto del pH de las solución de iones Pb(II) sobre la capacidad de adsorción de estos materiales adsorbentes, se encontró que conforme se incremente el pH de la solución de plomo, se incrementa su capacidad de adsorción teniendo como máximos los valores de pH entre 4 y 6. Al determinar los parámetros termodinámicos de cada sistema en función de la temperatura se encontró que los tres sistemas estudiados proceden mediante mecanismos de fisisorción, son reacciones endotérmicas y espontáneas. En conclusión estos materiales sintetizados y caracterizados pueden ser empleados eficientemente en la remoción de iones Pb(II) en medio acuso y son útiles para el tratamiento de aguas residuales contaminadas con metales pesados

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Tommaseo, Caterina Elisabetta. "EXAFS-Untersuchungen zur Rolle von Silicium bei der Sorption von umweltrelevanten Schwermetallen (Zn, As, Pb) in Speichermineralen (FeOOH, CSH)." [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=968711227.

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Morales, Alejandra Leticia. "Magnetic and Structural Properties of Compounds in the Sr_2-xCa_xFeOsO₆ Phase Diagram." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1430999410.

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Centurião, Ana Paula Soares de Lima. "Ozonização catalítica de um efluente simulado de refinaria de petróleo utilizando Mn2O3, FeOOH ou CeO2 em suspensão aquosa ou imobilizado em membrana cerâmica." reponame:Repositório Institucional da UFSC, 2017. https://repositorio.ufsc.br/xmlui/handle/123456789/181581.

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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Química, Florianópolis, 2017.
Made available in DSpace on 2017-12-05T03:11:01Z (GMT). No. of bitstreams: 1 348929.pdf: 2608513 bytes, checksum: 3bc6f375c172c5a28e81fbcfdcd246d0 (MD5) Previous issue date: 2017
A atividade catalítica de nanopartículas de Mn2O3, CeO2 e FeOOH para tratar efluente simulado de refinaria de petróleo (ESRP) usando O3 em um reator descontínuo foi avaliada em 25 °C e pH 5,5. Os catalisadores foram caracterizados através de fisissorção de N2, difração de raios-X (DRX), microscopia eletrônica de varredura (MEV) e transmissão (TEM), espectroscopia de fotoelétrons de raios-X e análise termogravométrica (ATG). Os resultados mostraram que a ozonização catalítica do ESRP na presença de nanopartículas de Mn2O3, CeO2 e FeOOH, apresentou maior remoção tanto do carbono orgânico total (COT) quanto da demanda química de oxigênio (DQO) quando comparada com a ozonização não catalítica. Entre os três catalisadores, o Mn2O3 foi o que apresentou a maior atividade catalítica e, por isso, foi feito um estudo detalhado do processo catalítico quando este foi empregado como catalisador. Nesse estudo detalhado para o Mn2O3, foram avaliados parâmetros como a influência da dosagem do catalisador e o efeito do pH inicial do ESRP na ozonização catalítica do efluente. Observou-se que a fração orgânica mineralizada (COT) aumentou progressivamente no processo catalítico, enquanto que no processo não-catalítico observou-se uma constância na taxa de mineralização. A relação entre a taxa de mineralização e a taxa de oxidação (DQO) mostrou que a taxa de mineralização é menor que a taxa de oxidação devido à formação de subprodutos parcialmente oxidados e depende da dosagem de catalisador e do pH inicial do efluente. Foi proposto um possível mecanismo de ozonização catalítica de ESRP sobre o catalisador de Mn2O3. O processo de oxidação catalítica também foi avaliado no processo híbrido ozonização- ultrafiltração em membranas cerâmicas como suporte para os catalisadores de óxidos metálicos (Mn2O3 e FeOOH). Testes de permeação na membrana não catalítica indicaram que a retenção física é desprezível e não contribui para a redução da concentração de COT e DQO. A deposição layer-by-layer das nanopartículas de Mn2O3 e FeOOH resultou na produção de membranas estáveis à permeação do soluto. Na presença de O3, observou-se que o fluxo de permeado permanece inalterado por um tempo maior de operação do que com o uso da membrana não catalítica, indicando que as reações superficiais com O3 contribuem para a diminuição do fouling e aumento do tempo de vida útil da membrana.
Abstract : The catalytic activity of Mn2O3, CeO2 and FeOOH nanoparticles to treat Simulated Petroleum Refinery Wastewater (SPRW) using O3 in a batch reactor was evaluated at 25 °C and pH 5,5. The catalysts were characterized by N2 adsorption/desorption isotherm, X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission (TEM), X-ray photoelectron spectroscopy and thermogravimetric analysis (TGA). The results showed that SPRW catalytic ozonation in the presence of Mn2O3, CeO2 and FeOOH nanoparticles showed higher removal of total organic carbon (TOC) and chemical oxygen demand (COD) when compared to non-catalytic ozonation. Among the three catalysts, Mn2O3 was the one that presented the highest catalytic activity and, therefore, a detailed study of the catalytic process was done when Mn2O3 was used as catalyst. In this detailed study for Mn2O3, parameters such as the influence of the catalyst dosage and the effect of the initial pH of the SPRW on the catalytic ozonation of the wastewater were evaluated. It was observed that the mineralized fraction (TOC) increased progressively in the catalytic process, whereas in the non- catalytic process a constancy in the mineralization rate was observed. The relationship between the mineralization and the oxidation rate (COD) has shown that the mineralization rate is less than the oxidation rate due to the formation of partially oxidized byproducts and depends on the wastewater catalyst dosage and the initial pH. A possible mechanism of SPRWcatalytic ozonation over the Mn2O3 catalyst has been proposed. The catalytic oxidation process was also evaluated in the hybrid ozonation-ultrafiltration process in ceramic membranes as a support for the metal oxide catalysts (Mn2O3 and FeOOH). Permeation tests on the non-catalytic membrane indicated that the physical retention is negligible, and does not contribute to the reduction of the concentration of TOC and COD. The layer-by-layer deposition of Mn2O3 and FeOOH nanoparticles, resulted in the production of stable membranes to solute permeation. In the presence of O3, it was observed that the permeate flux remains unchanged for a longer time of operation than with the use of the non-catalytic membrane, indicating that the superficial reactions with O3 contribute to the fouling decrease and membrane life time increase.

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Darracq, Stéphane. "Contribution à l'étude des corrélations entre stoechiométrie, structure, liaison chimique et propriétes physico-chimiques de perovskites oxygénées renfermant un élément 3d a un degrè d'oxydation inusuel (Cu(III), Cu(IV), Fe(IV))." Phd thesis, Université Sciences et Technologies - Bordeaux I, 1993. http://tel.archives-ouvertes.fr/tel-00136172.

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Ce mémoire concerne l'influence d'un degré d'oxydation inusuel d' un element de transition (Cu(III), Cu(IV), Fe(IV)) sur les proprietes physico-chimiques des réseaux oxygènes dérivés de structure perovskite. Les différentes structures du compose du cuivre trivalent LaCuO3 (formes basse et haute pression) ont été étudiées. Le role de plusieurs facteurs sur les propriétés physiques de ce matériau a pu etre mis en évidence, en particulier: 1) l'accroissement de la covalence moyenne de la liaison Cu-O du a la stabilisation de la valence mixte Cu(III)/Cu(IV) obtenue par substitution du Sr au La; 2) la distorsion structurale induite par substitution de l'yttrium au lanthane; 3) la pression d'oxygène de synthèse. La seconde partie de ce travail permet, au travers d' une étude Mössbauer par sonde diamagnétique locale (119Sn), d' expliquer le mécanisme de dismutation du fer tétravalent au sein d'un réseau perovskite AFeO3 (A=Ca, Sr)

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Sampsonis, Florence. "Entre le roi et le prince : la principauté de Morée aux mains des rois de Sicile : Charles 1er et Charles II d'Anjou (1267-1309)." Thesis, Paris 1, 2016. http://www.theses.fr/2016PA01H021.

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A partir de l'étude approfondie des registres angevins de Naples, l'objet de cette thèse est d'analyser les caractéristiques du pouvoir angevin établi dans la principauté de Morée, depuis sa cession par le prince Guillaume de Villehardouin au roi Charles Ier d'Anjou en 1267, jusqu'à la mort de Charles II d'Anjou en 1309. Seigneurs supérieurs de toute la principauté durant toute cette période, et même princes effectifs de la Morée entre 1278 et 1289, les rois de Sicile ont eu le souci de gouverner ce territoire en mettant en place une administration efficace et centralisée, s'appuyant à la fois sur les ressources humaines de leur royaume et sur les élites moréotes, menant leurs politiques dans le respect des coutumes locales. Ils ne remirent pas en cause les structures féodales et religieuses de la principauté, et encouragèrent les échanges commerciaux avec la Morée. Imposant leur autorité aux princes et à la princesse Isabelle de Villehardouin, les angevins ont su gérer plusieurs conflits, y compris celui opposant le prince au duc d'Athènes. Ils n'ont pu cependant reprendre les territoires conquis par les Byzantins : si Charles Ier a mené plusieurs opérations militaires dans le Péloponnèse, sans réel succès, la crise de Vêpres Siciliennes a mis un terme à ses ambitions militaires, Charles II laissant la défense de la péninsule aux mains des princes. Devenue dépendante du Royaume de Sicile, notamment avec la destitution de la princesse Isabelle en 1304, la principauté de Morée devint alors une simple province périphérique du royaume Angevin
Based on the thorought study of the Angevins registers of Naples, this doctoral thesis aims at analysing the caracteristics of the Angevin power established in the principality of Morea, from its transfer by prince William of Villehardouin to the king Charles Ist of Anjou in 1309, until the death of Charles II of Anjou in 1309. Superior lords of the principality during this period, and effective princes of Morea between 1278 and 1289, the kings of Sicily cared about governing this territory, installing an efficient and centralized administration, leaning both on the human resources of their kingdom and on the Moreotes elites, leading their politics in the respect of the local customs. They didn't change the feodal and religious structures of the principality, and they stimulated commercial exchanges with Morea. They imposed their authority to the princes and the princess Isabelle of Villehardouin. The angevins succed in managing several conflicts, even the one between the prince and the duke of Athens. But they couldn't retake the territories capures by the Byzantins : if Charles Ist lead several military operations in the Peloponese without real success, the Sicilian Vespers crisis put an end to his military ambitions. Charles II let the defense of the principality to the prince hands. The principilaty of Morea became dependant on the kingdom of Sicily, especially with the deposition of the princess Isabelle in 1304, and became then a mere peripheral province of the kingdom of Sicily

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Powell, Elisabeth, University of Western Sydney, College of Arts, and School of Humanities and Languages. "A literature of modern suffering : suffering in the work of Feodor Dostoevsky, Albert Camus and Milan Kundera." 2007. http://handle.uws.edu.au:8081/1959.7/15716.

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This thesis examines the treatment of the theme of suffering by three modern authors: Feodor Dostoevsky, Albert Camus, and Milan Kundera. The analysis proceeds through the identification and examination of three primary concepts which I will argue are at the heart of their work, and which provide the conceptual foundations for their depictions of suffering: the wretched, the absurd, and the banal. These concepts will be used as an avenue through which to explore and articulate their treatment of suffering. It will be argued further that the work of these three authors forms a conceptual series, in that each contributes in an important way to the evolution of a modern secular way of thinking about suffering by producing portraits of suffering informed by concepts appropriate to specific moments in the modern era. The sense of wretchedness which emerges from Dostoevsky’s work is inextricably linked with the late nineteenth-century crisis-of-faith. The concept of the absurd ties Camus to the early-twentieth-century existentialist tradition, while the sense of banality in Kundera’s novels locates him in an era which has witnessed both the horrors of World War Two and the decline in the humanist tradition. The factor that unites them and gives order to their differences, however, is a common concern with questions of meaning. The loss of meaning in the modern era, and in particular the loss of meaning in relation to suffering, is a thread which develops progressively throughout the series. It is, as will be argued at the outset, what binds these three disparate authors together and what gives their work and their treatment of suffering a particular modern character.
Doctor of Philosophy (PhD)

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Powell, Elisabeth. "A literature of modern suffering : suffering in the work of Feodor Dostoevsky, Albert Camus and Milan Kundera." Thesis, 2007. http://handle.uws.edu.au:8081/1959.7/15716.

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This thesis examines the treatment of the theme of suffering by three modern authors: Feodor Dostoevsky, Albert Camus, and Milan Kundera. The analysis proceeds through the identification and examination of three primary concepts which I will argue are at the heart of their work, and which provide the conceptual foundations for their depictions of suffering: the wretched, the absurd, and the banal. These concepts will be used as an avenue through which to explore and articulate their treatment of suffering. It will be argued further that the work of these three authors forms a conceptual series, in that each contributes in an important way to the evolution of a modern secular way of thinking about suffering by producing portraits of suffering informed by concepts appropriate to specific moments in the modern era. The sense of wretchedness which emerges from Dostoevsky’s work is inextricably linked with the late nineteenth-century crisis-of-faith. The concept of the absurd ties Camus to the early-twentieth-century existentialist tradition, while the sense of banality in Kundera’s novels locates him in an era which has witnessed both the horrors of World War Two and the decline in the humanist tradition. The factor that unites them and gives order to their differences, however, is a common concern with questions of meaning. The loss of meaning in the modern era, and in particular the loss of meaning in relation to suffering, is a thread which develops progressively throughout the series. It is, as will be argued at the outset, what binds these three disparate authors together and what gives their work and their treatment of suffering a particular modern character.

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HUANG, LIANG-HUA, and 黃亮華. "La femme au temps feodal en France." Thesis, 1988. http://ndltd.ncl.edu.tw/handle/77680167443154934932.

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Ruo-LinHuang and 黃若琳. "Synthesis and application of MnO2 and MnO2/FeOOH." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/92905556029603249526.

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碩士
國立成功大學
化學工程學系碩博士班
101
This work successfully synthesized manganese dioxide through the chemical oxidation of manganese ions (Mn(II)) by hypochlorous acid. The result showed that increasing hypochlorous acid will improve the oxidation yield of manganese dioxide. The XRD patterns confirmed that the manganese dioxide majorly consisted of Akhtenskite (ε-MnO2) phase. The BET surface area of the manganese dioxide, determined by N2 adsorption, was 95.27 m2/g . The pHzpc of the manganese dioxide determined using a zeta potential meter was 3.4 0.5. To examine the synthetic manganese dioxides’ capability of acting as a catalyst and an oxidant. The experiments of hydrogen peroxide degradation and oxalic acid mineralization were then carried out. The 10 mM of hydrogen peroxide could be degraded by 0.1 g of ε-MnO2 in 20 minutes. The degradation of hydrogen peroxide was a second-order reaction and the reaction rate constant ( ) was 3.352 M-1•s-1. The 2.425 mM of oxalic acid also could be mineralized by 1 g of ε-MnO2 in 2 hours. On the other hand, a novel multi-functional MBT9 was prepared by deposition of the manganese dioxide onto an iron oxide, BT9; the amounts of deposition were optimized by the ratio of hypochlorous acid to manganese (II) (HOCl/Mn). By jar-test process, a maximum molar ratio of Mn to Fe was 0.18 by adjusting HOCl/Mn to 10. As HOCl/Mn was decreased to 1, the molar ratio of Mn to Fe was declined to 0.02. The manganese dioxide on MBT9 that underwent an additional oxidation of As (III) could substantially enhance the arsenic adsorption. M9BT9 with a 0.09 molar ratio of Mn to Fe could attain a maximum adsorption amount of As (III), 32.2 mg/g. The As (III) adsorption using M9BT9 followed a second-order behavior. The sorption isotherms could be well fitted with Langmuir model, revealing that As(III) adsorption capacity of M9BT9 was 32.2 mg/g, higher than that of BT9 (21.79 mg/g). The As (V) adsorption capacity of M9BT9 was 18.7 mg/g which was lower than that of BT9 (26.9 mg/g). High capacity of M9BT9 for As (III) was attributed to the surface manganese dioxide capable of oxidizing As (III) to As (V); however, low capacity of M9BT9 for As (V) was due to the relatively low surface potential than BT9.

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Chen, Pi-Yu, and 陳碧玉. "Simultaneous NO Reduction / CO Oxidation By FeOOH Catalyst." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/44682343965861566721.

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碩士
國立臺北科技大學
環境規劃與管理研究所
95
FeOOH was used in this study to evaluate the efficiencies of simultaneously reduction of NO and oxidization of CO by a packed bed reactor. There were four reaction parameters in this study: reaction temperature, NO influent, CO influent and FeOOH dosage. Possible reaction steps were investigated by X-Ray Diffraction (XRD) spectrum from raw and reacted FeOOH. It is observed that with higher reaction temperature, the removal efficiency of both NO and CO were higher. When reaction temperature increased from 373 K to 673 K, NO removal efficiency was linearly correlated with reaction temperature. NO removal efficiency was over 98% for NO influent concentrations of 240~720 ppmv with CO concentration of 1910 ppmv with FeOOH of 3g. When NO influent over 720 ppmv, NO removal efficiency decreased due to the FeOOH is used up. NO removal efficiency was only 6 % when CO reacted efficiency was 31~36 % at lower FeOOH Dosage 2~3g, indicating there were no sufficient sites for reactions to provide NO reduction. The higher dosage of FeOOH (4~6g) results in higher removal efficiency of NO and CO. Regression analysis shows the rank for these parameters is CO influent >CO reacted efficiency> NO influent > FeOOH Dosage > temperature XRD (X-Ray Diffraction) was conducted to analyze the crystal structure and oxidation state of the raw and reacted FeOOH. It is demonstrated that carbon monoxide reduced Fe3+ ion of FeOOH to Fe2+ and nitric oxide oxidized Fe2+ back to Fe3+ ion, indicating FeOOH is a catalyst in the reaction.

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45

Chou, Shanshan, and 周珊珊. "Development of Supported-FeOOH Fluidized Bed: Feasibility, Kinetics, and Optimization." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/97744272087755109049.

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博士
國立交通大學
環境工程所
87
Hydroxyl radical is very reactive, underlying the chemistry of advanced oxidation processes (AOPs) for degrading organic compounds in water. Among various AOPs, Fenton’s reagent (H2O2/Fe2+) has been known to be an effective and simple oxidant. The major drawback of Fenton’s reaction is the production of substantial amount of Fe(OH)3 sludge that requires further separation and disposal. To solve this problem, the application of iron oxide as the heterogeneous catalyst in oxidizing organic contaminants deserves an in-depth investigation. In this study, a novel supported-FeOOH catalytic fluidized-bed reactor (FBR) was developed. The FBR may be better suited for the application in practice because of its high efficiency in mass transfer and easy solid/liquid separation. The crystallization of supported FeOOH, feasibility of oxidizing benzoic acid (BA), kinetics of decomposing H2O2 and oxidizing BA were investigated. Eventually, this reactor was used to treat a real dyeing/finishing wastewater, and the optimization of operating conditions was performed. The innovative catalyst (supported FeOOH) was prepared via the oxidation of Fe2+ by H2O2 in the acidic condition using a fluidized-bed crystallization reactor (crystallization-FBR). The major components coated on the surface were identified as amorphous FeOOH and *-FeOOH. The metastable region was found first to decide the rough inlet reagent concentration of crystallization-FBR to prevent the formation of primary nucleation. The characteristics of supported FeOOH including the particle morphology, Mossbauer spectrum, total and oxalate-soluble Fe contents, and the specific surface area were determined. Three kinds of supported FeOOH grains were synthesized: FeOOH I was prepared at pH 3.5, FeOOH II was formed by aging FeOOH I at pH 13, and FeOOH III was prepared at pH 5.0. FeOOH I was applied in following experiments including feasibility and kinetic studies of oxidizing BA, and treatment of the dyeing/finishing wastewater. FeOOH II and FeOOH III were used to compare the catalytic performance with FeOOH I. The crystalline property was found to obviously influence the performance of catalytic oxidation. In the aspect about the crystallization conditions of supported FeOOH, some parameters including the operational pH, superficial velocity, specific iron loading, and influent H2O2 concentration were investigated their effects on the crystallization efficiency. All these parameters were found to be the factors influencing the crystallization efficiency, but only the operational pH affected iron oxide type of grown crystal. The feasibility study about the H2O2 decomposition and BA oxidation using the supported-FeOOH catalyst was studied in the batch reactors. The kinetics of H2O2 decomposition in the absence of BA was conducted first. Oxidation of BA by H2O2 was performed so as to understand the effects of pH, H2O2 dosage, and the catalyst concentration. The treatment efficiency of BA at an initial pH of 3.2 was higher than at initial pHs of 6.0 and 10.0; this can be explained by the reductive dissolution of FeOOH in acidic environment. At the initial stage of reaction, however, the oxidation of BA was mostly contributed by heterogeneous catalysis because of trace amount of dissolved Fe2+. The higher initial oxidation rate of BA by heterogeneous catalysis at pHi 3.2 was due to its higher amount of undissociated BA adsorbed on the FeOOH surface. Therefore, the extent of heterogeneous catalysis was evaluated by comparing with an equivalent concentration of soluble ferrous ion in a parallel experiment. It is concluded that this catalytic oxidation mostly occurred on the catalyst surface, with some occurred in the aqueous solution due to the iron dissolution of the catalyst. In the absence of BA, the kinetics about the decomposition of H2O2 by the supported-FeOOH catalyst was performed in a continuous FBR. In this part, we attempted to study the effects of pH, H2O2 concentration, and catalyst concentration on the decomposition of H2O2. At the lower H2O2 concentration, the decomposing rate of H2O2 was found to be proportional to both H2O2 and catalyst concentrations. At the higher H2O2 concentration, however, it decreased with the increasing H2O2 concentration. This phenomenon was well fit with the substrate inhibition model. The significant difference of the observed first-order rate constant under different pH values was also modeled. In the part of oxidizing BA by the supported-FeOOH catalytic FBR, the effects of pH, H2O2 concentration, and BA concentration on the oxidation of BA were studied. The another aim of oxidizing BA using the continuous FBR was to realize the proportions of homogeneous catalysis and heterogeneous catalysis. It was found that the oxidation rate of BA was dependent on both H2O2 and BA concentrations. The change in rate constant of heterogeneous catalysis by pH was described in terms of the ionization fractions of surface hydroxyl group. From the mathematical deduction, we suggest that the reaction rate associated with FeIIIOH2+ is much higher than with FeIIIOH. Conclusively, the oxidation of BA at pH 4.4 ~ 7.0 is contributed by heterogeneous catalysis alone, but the homogeneous catalysis is of increasing importance below pH 4.4. The effect of Fe2+ on the catalytic oxidation in the FBR was also examined. The process with Fe2+ addition is named FBR-Fenton method, in which Fe2+ is the homogeneous catalyst and FeOOH is heterogeneous catalyst to oxidize BA. Both mineralization of organics and crystallization of Fe(III) were simultaneously well performed under the adequate condition. The efficiencies of BA mineralization and Fe(III) crystallization both closely related to the pH and inlet Fe2+ concentration. The reaction mechanism of FBR-Fenton method, including the reductive dissolution of FeOOH, synthesis of FeOOH, and oxidation of BA, was proposed based on experimental results. Finally, the FBR-Fenton method was applied to treat a dyeing/finishing wastewater, and the optimal operating conditions were found by the experimental design analysis. The methods of experimental design used here included the fractional factorial design, central composite design (CCD), and response surface methodology (RSM). Three most influential variables were decided by the fractional factorial design. Using these three variables, the regression models for the removal efficiencies of TOC (TOCr) and Fe (Fer) were determined by CCD and RSM. To select the optimal operating conditions, five conflicting criteria including pH, H2O2 dosage/COD, Fe2+/H2O2, TOCr and Fer were considered on the basis of Derringer’s desirability function. Furthermore, the FBR-Fenton method was proven superior to the conventional Fenton’s reaction due to high removal of TOC, effective Fe removal, and little sludge production by FBR-Fenton method.

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46

Hsuan-TangWang and 王炫棠. "Synthesis of bimetallic MnO2/FeOOH using fluid-ized-bed crystallization." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/q62f79.

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47

Chen, Yu-hao, and 陳宇豪. "Synthesis and characterization of multi-walled carbon nanotubes/β-FeOOH Nanocomposites." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/6n28hr.

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碩士
大同大學
材料工程學系(所)
102
Our study was focused on preparation and capacity characteristic of the composite CNTs/β-FeOOH electrode, which was composed of different weight ratios of multi-walled carbon nanotubes (CNTs), β-FeOOH and carbon black. β-ferric oxyhydroxide (β-FeOOH) nanoparticles were synthesized by ultrasonic assisted in situ hydrolysis of the precursor ferric chloride. Different weight ratios of multi-walled carbon nanotubes (CNTs) prepared the composite CNTs/β-FeOOH electrode. FeCl3·6H2O was employed as the precursor for the synthesis of β-FeOOH nanoparticles. FeCl3·6H2O was first dissolved in distilled water to produce solution under magnetic stirring. The stable aqueous suspension was then long drawn reflux condensed in a thermostatic water bath. During this hydrolytic process, the suspension was ultra sonicated for 10 min every 1 h. After approximately 4 h, the products were cooled to room temperature and isolated by centrifugation. Finally, the products were dried in air. The composite electrode was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM),and transmission electron microscopy (TEM). The Measurement of the electrochemical properties such as capacitance was conducted using a electrochemical workstation (Jiehan 500) for cyclic voltammetry. The effects of the CNTs on the capacitive properties of the β-FeOOH electrode were studied in our work and be discussed in this paper.

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48

Lin, Sheng-Han, and 林昇翰. "Oil/water separation performance of melamine sponge fabricated by superhydrophobic β-FeOOH nanoparticles." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/vfsddc.

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碩士
國立臺灣大學
環境工程學研究所
107
Because of modern vehicle technology, oil spill caused by ship accidents happens frequently. To avoid oil pollution in marine environment and remain reusability of oil-adsorbing materials, 3D porous materials fabricated by superhydrophobic coating have been a new direction of development. However, at the present time, this kind of materials have disadvantages of complicated production process and high energy cost. To look for high quality, low-cost and easy-making material, in this study, we will try to use melamine foam fabricated by superhydrophoic β-FeOOH nanoparticles to adsorb oil and measure its maximum adsorption capacity, separation efficiency, oil removal efficiency, durability and reusability as performance evaluation indicators. Melamine foam fabricated by β-FeOOH nanoparticle, which is abbreviated as MF-β-FeOOH, have high hydrophobicity because of 144.23˚ water contact angle. In addition, the maximum adsorption capacity of this materials according to different kinds of oil is 68.2 ~ 104.5 g/g, and the separation efficiency is 95.3% ~ 99.5%. Last but not least, the oil removal efficiency is approximately 99.1%, so we can prove that MF-β-FeOOH have good oil-water separation performance. In terms of duration test, oil removal efficiency of MF-β-FeOOH can be above 98.6% in acidic and neutral water environment and a little bit lower efficiency about 97.8% in basic water environment. Therefore, it can remain good efficiency in pH 1 to 13. Additionally, MF-β-FeOOH also can adsorb oil in sea water, which has oil removal efficiency about 98.7% and its chemical structure has enough thermal stability in water, based on TGA analysis. Finally, MF-β-FeOOH have good reusability since its maximum adsorption capacity can remain 72% of new one and about 98% oil removal efficiency after 20 cycles of adsorption process. To sum up, based on former data, we can prove that MF-β-FeOOH is a good oil-adsorbing material.

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49

莊弘任. "EDTA wastwater treatment by fluidized bed-fenton system:preparation of supported-FeOOH and its characteristics." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/05267098783787640856.

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50

Wu, Chung-Chu, and 吳忠柱. "The Effect of α-FeOOH Coating on Desulfurization Slag for the Removal of Humic Acids." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/42848381941107108292.

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碩士
國立成功大學
環境工程學系
86
Adsorption of humic acid by desulfurization slag (DS) was conducted by both batch and column experiments to investigate the capabilities of DS for refractory organic removal. Also,α- FeOOH was synthesized by ferric nitrate andthen coated on desulfurization slag to examine its effect on the adsorptionefficacy.The results from SEM, TEM,and XRD analysis show that α-FeOOH was successfullysynthesized by ferric nitrate at high pH situation, the synthesizedα-FeOOH exhibits rod and needle in morphology with high BET surface area of 120-140m2/g. In the batch isotherm adsorption experiments, DS presents high adsorption capacity for humic acid and the DOC removal efficiency of 76.67% was obtained.It is due to the coagulation/ adsorption effect of free CaO on DS surface at highpH situation (pH>11). On the other hand, the adsorption efficacy of DS waseliminate as α-FeOOH coated on the DS surface. It is because that the coatedα-FeOOH would fulfill the micropore and also depress the coagulation/adsorptioneffect of free CaO of DS. Similar results also can be found in column adsorptiontests. The breakthrough curve of DS was retarded at C/Co of 20% while that ofthe α-FeOOH coated DS was retarded at C/Co of 40%.Key words: α-FeOOH, desulfurization slag, humic acid, adsorption

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