Este trabalho tem por objetivo analisar a produção do adubo obtido a partir do resíduo da raspa do couro bovino, curtido ao cromo (III), bem como avaliar a viabilidade de ganhos ambientais e energéticos que ao adubo se atribui. A metodologia usada foi estabelecida a partir de uma revisão bibliográfica sobre as alternativas para o gerenciamento de resíduo sólido da indústria de beneficiamento do couro e no estudo do efeito do cromo no meio ambiente, fundamentada na teoria das restrições no aspecto ambiental e energético. Para a implementação da parte experimental e produção do adubo da raspa do couro bovino hidrolisado foi montado um protótipo composto de três componentes: caldeira, autoclave e secador, considerando-se os parâmetros termodinâmicos: temperatura de 403 a 433 K e a pressão de 700 a 800 kPa. No decorrer desse processo automaticamente controlado, calcularam-se as incertezas das medidas efetuadas nos parâmetros do adubo e do solo, da pressão e a produção de vapor gerado pela caldeira, bem como nas medições dos equipamentos, autoclave e secador com suas respectivas densidades, obtendo-se a relação de massa e volume. As amostras foram analisadas para verificar os teores máximos e mínimos dos macro e micronutrientes, assim como seus elementos de maior relevância. Foram avaliadas as características fisico-químicas e agronômicas do produto, o balanço de massa e a energia da produção do adubo. A experiência aplicada com o adubo na cultura do milho foi realizada em casa de vegetação, com delineamento inteiramente casualizado com quatro repetições. Os tratamentos constituíram-se a partir da utilização de dois tipos de adubo de apara de couro (resíduo italiano e resíduo brasileiro) e sulfato de amônio como fonte de nitrogênio em três doses. Foram utilizados dois tipos de solo: Latossolo Férrico e Latossolo Vermelho Amarelo. A produção desse adubo será implantada industrialmente para a redução do impacto ambiental provocado pelas indústrias de beneficiamento do couro e também para a agricultura, uma vez que esse adubo é um produto rico em nitrogênio. / The purpose of this study is to analyze the production of fertilizer obtained from cow leather shavings cured with Chrome (III), as well as the viability for this fertilizer to contribute for environmental and energetic gains. The methodology was based on a review of bibliographic material of the alternatives for management of solid waste from the leather industry and on a study of the effect of chrome on the environment based on the theory of restrictions, with concern for environmental and energy factors. The experimental portion of the study involved the assemblage of a prototype composed of three pieces of equipment: a boiler, an autoclave and a dryer, for the production of fertilizer from hydrolyzed cow leather shavings. In relation to the thermodynamic process, the temperature was maintained at 403 and 430 K and pressure at 700 and 800 kPa. During this automatically controlled process, the uncertainties in the measurements conducted in the parameters of fertilizer and soil were calculated of pressure and production of steam generated by the boiler and the readings of the autoclave and dryer equipment were calculated in addition to their respective densities, to obtain the ratio of mass and volume. The samples were analyzed to determine the maximum and minimum amounts of the macro and micro nutrients and their most important elements. The physical-chemical and agronomic characteristics of the product were evaluated as well as the balance of mass and energy of the fertilizer production. The experiment conducted with fertilizer from cow leather applied to a corn crop, was conducted in a vegetable greenhouse, with completely arbitrary delineation and four repetitions. The treatment involved the use of two types of fertilizer made from leather shavings (Italian residue and Brazilian residue) and ammonia sulfate as a nitrogen source in three doses. Two types of soil were used: Ferric Latosol and Red-Yellow Latosol. The fertilizer can be produced industrially to reduce the environmental impact caused by leather manufacturing companies and to agriculture because it is rich in nitrogen.

Este trabalho tem por objetivo analisar a produção do adubo obtido a partir do resíduo da raspa do couro bovino, curtido ao cromo (III), bem como avaliar a viabilidade de ganhos ambientais e energéticos que ao adubo se atribui. A metodologia usada foi estabelecida a partir de uma revisão bibliográfica sobre as alternativas para o gerenciamento de resíduo sólido da indústria de beneficiamento do couro e no estudo do efeito do cromo no meio ambiente, fundamentada na teoria das restrições no aspecto ambiental e energético. Para a implementação da parte experimental e produção do adubo da raspa do couro bovino hidrolisado foi montado um protótipo composto de três componentes: caldeira, autoclave e secador, considerando-se os parâmetros termodinâmicos: temperatura de 403 a 433 K e a pressão de 700 a 800 kPa. No decorrer desse processo automaticamente controlado, calcularam-se as incertezas das medidas efetuadas nos parâmetros do adubo e do solo, da pressão e a produção de vapor gerado pela caldeira, bem como nas medições dos equipamentos, autoclave e secador com suas respectivas densidades, obtendo-se a relação de massa e volume. As amostras foram analisadas para verificar os teores máximos e mínimos dos macro e micronutrientes, assim como seus elementos de maior relevância. Foram avaliadas as características fisico-químicas e agronômicas do produto, o balanço de massa e a energia da produção do adubo. A experiência aplicada com o adubo na cultura do milho foi realizada em casa de vegetação, com delineamento inteiramente casualizado com quatro repetições. Os tratamentos constituíram-se a partir da utilização de dois tipos de adubo de apara de couro (resíduo italiano e resíduo brasileiro) e sulfato de amônio como fonte de nitrogênio em três doses. Foram utilizados dois tipos de solo: Latossolo Férrico e Latossolo Vermelho Amarelo. A produção desse adubo será implantada industrialmente para a redução do impacto ambiental provocado pelas indústrias de beneficiamento do couro e também para a agricultura, uma vez que esse adubo é um produto rico em nitrogênio. / The purpose of this study is to analyze the production of fertilizer obtained from cow leather shavings cured with Chrome (III), as well as the viability for this fertilizer to contribute for environmental and energetic gains. The methodology was based on a review of bibliographic material of the alternatives for management of solid waste from the leather industry and on a study of the effect of chrome on the environment based on the theory of restrictions, with concern for environmental and energy factors. The experimental portion of the study involved the assemblage of a prototype composed of three pieces of equipment: a boiler, an autoclave and a dryer, for the production of fertilizer from hydrolyzed cow leather shavings. In relation to the thermodynamic process, the temperature was maintained at 403 and 430 K and pressure at 700 and 800 kPa. During this automatically controlled process, the uncertainties in the measurements conducted in the parameters of fertilizer and soil were calculated of pressure and production of steam generated by the boiler and the readings of the autoclave and dryer equipment were calculated in addition to their respective densities, to obtain the ratio of mass and volume. The samples were analyzed to determine the maximum and minimum amounts of the macro and micro nutrients and their most important elements. The physical-chemical and agronomic characteristics of the product were evaluated as well as the balance of mass and energy of the fertilizer production. The experiment conducted with fertilizer from cow leather applied to a corn crop, was conducted in a vegetable greenhouse, with completely arbitrary delineation and four repetitions. The treatment involved the use of two types of fertilizer made from leather shavings (Italian residue and Brazilian residue) and ammonia sulfate as a nitrogen source in three doses. Two types of soil were used: Ferric Latosol and Red-Yellow Latosol. The fertilizer can be produced industrially to reduce the environmental impact caused by leather manufacturing companies and to agriculture because it is rich in nitrogen.

Na área de Química, uma das linhas mais tradicionais de pesquisa envolve o estudo de formação de complexos. Estes trabalhos são realizados de modo sistemático em nossos laboratórios, geralmente envolvendo cátions de metais de transição com vários ligantes (haletos, pseudo-haletos e carboxilatos). A intensa coloração desenvolvida pela maioria dessas reações de complexação, entre um metal e um pseudo-haleto, tem motivado o desenvolvimento de novos métodos espectrofotométricos para a determinação de íons em amostras reais. Espera-se que o crômio(III), da mesma forma que outros metais de transição, como o ferro, níquel e cobalto, forme complexos com o pseudo-haleto denominado azida ou azoteto (N3-). Desta forma, dando continuidade a esta linha de pesquisa, este trabalho teve como objetivo otimizar as condições experimentais para o sistema crômio(III)/azoteto. Diversos parâmetros como acidez, concentração de ligante, natureza e concentração de solvente, bem como o efeito da temperatura, foram investigados. Reunidas as melhores condições (otimização), montou-se o método analítico que possibilita a determinação do metal. As condições ideais empregadas foram: concentração analítica de ligante e ácido perclórico de 493 e 12,0 mmol L-1, respectivamente, numa temperatura de 25ºC, em meio aquoso. Para a determinação no ultravioleta, o tempo de espera para cada medida foi de 1 hora, enquanto que na região do visível, foi de apenas 30 minutos. Os máximos de absorção ocorreram em torno de 646, 480 e 287 nm, com coeficientes de absortividade molar médios de 184±1, 157±1 e (1,481±0,008) 104 L mol-1 cm-1, respectivamente. As condições estabelecidas foram promissoras, permitindo uma boa repetitividade nas regiões do visível e ultravioleta. Para o método desenvolvido, os íons mais interferentes na região do visível foram: Fe3+, Co2+ e Cu2+ e, na região do ultravioleta, foram HC8H4O4-, Fe3+, Cu2+ e Hg2+. Por meio de um sistema com duas equações, a determinação simultânea de crômio e ferro mostrou-se possível e com erros dentro dos limites analiticamente aceitáveis. Sem a utilização do sistema de equações, verificou-se ainda a possibilidade de se determinar crômio diretamente, mesmo na presença de ferro, no comprimento de onda de 646,5 nm, com um erro menor que 5%, desde que a concentração de ferro não ultrapasse 4 mg L-1. Aplicações analíticas para o método proposto foram testadas em dois suplementos alimentares contendo crômio. Os resultados foram comparados e mostraram-se concordantes com os da técnica de espectrometria de absorção atômica, para o suplemento contendo crômio quelato. Para o suplemento alimentar contendo picolinato de crômio, houve uma discordância dos resultados, indicando a existência de interferentes da matriz que não puderam ser eliminados. Um teste com uma amostra sintética de crômio mostrou um erro de cerca de 1,0% para o método proposto. Em condições ideais, e com um controle dos interferentes presentes, o método proposto mostra-se preciso, simples e barato. Considerando valores de absorbância entre 0,2 e 0,8 (faixa ideal), pode-se determinar o metal nos intervalos de 1,27 a 5,09 mmol L-1 a 480,5 nm, de 1,09 a 4,35 mmol L-1 a 646,5 nm e, finalmente, entre 0,702 a 2,81 mg L-1 no ultravioleta (287 nm). / In Chemistry, the study of complexes formation is one of the most traditional research lines. These studies are done under systematic manners in our laboratories, usually involving metallic transition cations with several ligands (halides, pseudohalides and carboxylates). The intense coloration developed by the major part of those complexation reactions, between a metal and a pseudohalide, has encouraged the development of new spectrophotometric methods for determination of ions in real samples. Conforming others transition metals, (iron, nickel and cobalt), which form complexes with the pseudohalide azide (N3-), we tried to observe the same behavior to chromium(III). Continuing this research line, this work had as principal objectives optimizes the experimental conditions for the chromium(III)/azide system. Several parameters were investigated as acidity, ligand concentration, nature and solvent concentration, as well as temperature effect for optimization of experimental conditions. Gathering all these conditions, the analytical methods were tested for the metal determination. The ideal conditions employed were: analytical ligand concentration and perchloric acid of 493 and 12.0 mmol L-l respectively, at 25 °C, in aqueous medium. For the studies in the ultraviolet region, the contact time before the measures was one hour, while for studies in the visible band measures were made after 30 minutes. The wavelengths of maximum absorption were encountered at 646, 480 and 287 nm, with molar absorptivity coefficients (mean) of 184±1, 157±1 and (1.481±0,008) 104 L mol-1 cm-1, respectively. The established conditions were promising, allowing a good precision in the visible and ultraviolet region. For the developed method, the more interfering ions on visible band were: Fe3+, Co2+ and Cu2+ and, on the ultraviolet band, were HC8H4O4-, Fe3+, Cu2+ and Hg2+. Through a system of two equations, the simultaneous determination of chromium and iron ions was possible with errors within the tolerance range. Without the simultaneous equations system, it was verified directly the possibility of chromium determination in the presence of iron, at a wavelength of 646.5 nm, with an error smaller than 5%, since the concentration of iron doesn’t exceed 4 mg L-l. In this proposed method, analytical applications were tested for two alimentary supplements containing chromium. The results were compared, being concordant with those of atomic absorption technique for the supplement containing chromium chelate, while for the alimentary supplement containing chromium picolinate, the results were in disagreement with the results, indicating the existence of matrix interferences which could not be eliminated. A test with a synthetic sample of chromium had an error of about 1.0% for the proposed method. Under ideal conditions, and with some control of possible interfering, the proposed method can be precise, accurate, simple and cheap. Considering the absorbance values between 0.2 and 0.8 (ideal range), the metal can be determined from 1.27 to 5.09 mmol L-l in 480 nm; 1.09 to 4.35 mmol L-l in 646 nm and, finally, from 0.702 to 2.81 mg L-l at 287 nm (ultraviolet).

Les oxydes de chrome permettent d’obtenir une large variété de couleurs, conduisant à leur utilisation répandue dans les arts céramiques. À la manufacture de Sèvres, leurs propriétés colorantes ont été explorées dès la découverte du chrome à la fin du 18ème siècle. Les travaux initiés par Brongniart ont conduit à une série de 76 pigments pour porcelaine composés d’oxydes de chrome, régulièrement synthétisés au laboratoire de la manufacture. Nous avons mené une étude exhaustive de ces pigments, permettant une classification basée sur leur analyse minéralogique et mettant en évidence le rôle du Cr3+ dans ces pigments, avec l’absence de Cr6+. Le mélange de ces pigments avec un composant incolore est appliqué sur la porcelaine, et porté à haute température afin d’obtenir un émail, c’est-à-dire une couche décorative partiellement vitreuse à la surface de la porcelaine. Les pigments composés de chrome se retrouvent dans les décors verts, roses, bleu-vert, marron et noirs. Après avoir caractérisé la spéciation et l’environnement du chrome dans l’ensemble de ces pigments, cette thèse s’est concentrée sur un pigment particulier, majoritairement composé de gahnite au chrome ZnAl2O4:Cr3+. Ce type de pigment a été identifié dans une série d’œuvres produites par la manufacture, entre la fin du 19ème et le début du 20ème siècle, correspondant à la période de l’art nouveau. La solution solide complète ZnAl2-xCrxO4 a été étudiée afin de préciser l’environnement structural du chrome, montrant l’importance des seconds voisins Cr dans les variations de couleur. Au cours de la cuisson de l’émail, un mécanisme de dissolution progressive des grains de pigments a été mis en évidence, résultant de l’interaction avec le composant incolore en cours de vitrification. Notre travail montre la faible solubilité du Cr dans le verre et sa spéciation préférentielle dans les cristaux, entrainant parfois des changements de phases ou des modifications de composition le long de solutions solides lors du traitement thermique à haute température. Ces modifications ont permis de mieux comprendre l’origine de la couleur dans les décors de porcelaine ainsi que les mécanismes de formation des émaux. / Chromium oxides are widely used in the ceramic industry because they are characterized by a large variety of colors. At the French porcelain manufacture of Sèvres, their coloring properties have been explored since the discovery of chromium at the end of the 18th century. The researches initiated by Brongniart lead to a group of 76 pigments for porcelain composed of chromium oxides, regularly synthesized at the laboratory of the manufacture. An exhaustive study was done on these pigments, which enables to propose a classification based on their mineralogical analysis and highlights the role of Cr3+ in the color of the pigments, without Cr6+. The mixture of one or two pigments and an uncolored frit is applied on the porcelain, and fired at high temperature to obtain a glaze, i.e. a partly glassy decorative layer on the top of the porcelain. Pigments composed of chromium are used to obtain green, pink, greenish-blue, brown and black glazes. This thesis focuses on a particular pigment, mainly composed of gahnite doped with chromium ZnAl2O4:Cr3+. This kind of pigment was identified in a collection of artefacts produced by the manufacture between the end of the 19th century and the beginning of the 20th century. This period corresponds to the artistic movement Art Nouveau. The solid solution ZnAl2-xCrxO4 was studied to get the structural environment of Cr, showing the role of the second neighbor Cr in the color variation. During firing of the glaze, a mechanism of gradual dissolution of the initial grains of pigments was determined, resulting of reactions with the uncolored frit. Our work shows the low solubility of Cr in glass and its preferential speciation in crystals, leading to crystalline phase changes or modifications of composition along solid solutions during the thermal treatment at high temperature. These modifications enable to understand the origin of color in porcelain glazes and the mechanism of glaze formation.

L'essor du domaine de l'électronique de spin a stimulé l'étude des propriétés de films minces ferromagnétiques utilisés pour la rétention et la lecture de l'information magnétique. Les films minces antiferromagnétiques, bien que mis en exergue par la démonstration de l'effet GMR dans des super-réseaux Fe/Cr, n'ont qu'un rôle auxiliaire dans ces dispositifs. Des études théoriques récentes proposent néanmoins de leur conférer un rôle actif avec des propriétés distinctes et compétitives, en remplacement des films ferromagnétiques. Contrairement aux couches ferromagnétiques, les films antiferromagnétiques ont été l'objet de beaucoup moins de travaux expérimentaux : l'ordre antiferromagnétique ne peut être étudié que par quelques techniques spécifiques, telles que la diffraction de neutrons. Au cours de cette thèse, nous avons examiné un système modèle pour l'électronique de spin, constitué d'une couche mince de chrome (001), archétype de matériau antiferromagnétique itinérant, et d'une couche d'oxyde de magnésium (001), barrière cristalline la plus largement utilisée. Nous avons montré qu'il était possible de contrôler l'anisotropie magnétique et l'ordre magnétique de l'antiferromagnétique grâce à une maîtrise fine des conditions de croissance et grâce au dopage par le Fe. Une étude détaillée par photoémission a permis d'approfondir les preuves du couplage du magnétisme et de la structure électronique du Cr, et en particulier de mettre en évidence des états de surface et d'interface polarisés. Ces résultats ont été complétés par la détermination du moment ferromagnétique d'interface du Cr/MgO (001) par réflectivité de neutrons. Enfin, en tirant parti de ce socle de connaissance, nous avons pu comprendre et interpréter le magnétisme caractéristique d'hétérostructures de Cr comportant une barrière cristalline fine de MgO, comme la signature d'un couplage tunnel intercouches / The development of spintronics has stimulated the study of ferromagnetic thin films, used for magnetic data recording and reading. Although the GMR effect has been demonstrated in Fe/Cr superlattices, antiferromagnetic thin films only play an auxiliary role for these devices. Recent theoretic studies however proposed they could play a more active role, replacing ferromagnetic thin films, with competitive and distinct properties. Contrary to ferromagnetic layers, antiferromagnetic thin films have been much less experimentally examined because specific techniques (like neutron diffraction) are needed to that purpose, beyond usual characterization means. During this thesis work, we examined a model system for spintronics consisting in a thin film of chromium (001), an archetypal itinerant antiferromagnet, and a (001) magnesium oxide layer, widely used as a crystalline tunnel barrier in spintronic devices. We have demonstrated the possibility to control the magnetic anisotropy and the magnetic order of the antiferromagnet by mastering the growth conditions, and by doping Cr with Fe. Thanks to a detailed photoemission study, we have extended proofs of the interplay between magnetism and electronic structure in Cr, and in particular, we have evidenced surface and interface polarized states. By completing these results with neutron reflectivity experiments, we determined the magnitude of the ferromagnetic moments at the Cr/MgO(001) interface. Finally, by exploiting this gathered amount of knowledge, we succeeded in understanding and interpreting the characteristic magnetism observed in Cr/MgO heterostructures with thin tunnel barriers as the sign of a tunnel interlayer coupling

Bibliography: pages 107-108. / The effects of exposure to temperatures in the range 475 - 800°C on the hardness and associated microstructure of high chromium ferritic steels has been investigated. Low-carbon 26Cr-1Mo steels containing 0,02 - 0,04% nitrogen were found to constitute an age hardening system when quenched from a temperature of nitrogen solubility and exposed at temperatures in the range 600 - 700°C. TEM observations on thin foils revealed that hardening was associated with the formation of a high density of Cr-N zones. These grew on over-ageing into disc-shaped Cr-N precipitates situated on {100} lattice planes, and ultimately became large incoherent precipitates. Ageing at 475°C and 550°C produced hardening due to the formation of chromium-rich ferrite phases α' as a result of the miscibility gap in the Fe-Cr phase diagram. However the presence of interstitial nitrogen in solution in the steel considerably reduced the rate of hardening, especially at 475°C. TEM examination confirmed that this effect was due to the formation of Cr-N zones in preference to α'. This type of decomposition occurs by a mechanism of nucleation and growth, forming zones similar to those formed during an ageing at 600°C. When depleted of interstitial nitrogen, through precipitation at 800°C or through zone formation at 475°C, the specimens aged at 475°C underwent spinodal decomposition. Thus nitrogen in solid solution was found to have a significant effect on the 475°C hardening reaction. Precision X-ray diffraction measurements revealed the presence of secondary diffraction peaks associated with the Bragg peaks, which comfirmed the formation of Cr-rich phases during ageing at 475°C. The calculated associated lattice parameter measurements allowed estimates of the compositions of the decomposition phases to be made. These were calculated to be about 6-18% Cr in the Fe-rich and 60-80% Cr in the Cr-rich phases of the 26Cr-1Mo steel.

This thesis is divided into three parts. The first part is focused on a description of the formulation of the extension for viewers Internet Explorer, Opera, Safari 5, Mozilla Firefox a Google Chrome, on summary of the facilities of development of the extension for these viewers and on structure of the extension factually for Google Chrome. The second part describes the installation of the extension for Chrome with method of the unpack extension and with method from the Internet shop Chrome. There is also described a detailed formulation of the extension for Chrome with examples of the code source, with possibility of the implementation and the commentary insert into websites. It further describes contribution of the extension and contribution of this thesis. The target of this thesis is to get acquainted with problems of the formulation of the extension of plugins for viewers Chrome or Firefox and to formulate an application, which it will be able to add the commentary to contents of the website.

<p> Emerging out of feminist and cyberpunk science fiction of the 1980s, feminist post-cyberpunk SF is a subgenre that is rife with anxieties over novel technologies (such as cloning, genetically modified foods, nanotechnology, virtual reality, telepresence, and artificial intelligence), as they infiltrate daily life and threaten to transform the definition of human being. In this project, Larissa Lai's Salt Fish Girl, Nalo Hopkinson's Midnight Robber, Tricia Sullivan's Maul, and Laura Mixon's Proxies are read as indicative examples of feminist post-cyberpunk, as they all give voice to the increasing shared cultural preoccupation with technology and the body. The thesis is particularly interested in the way these texts expose - and insist upon - the vulnerability of the fleshy body, rather than perpetuate notions of technophilia and technological transcendence. Drawing on the (corporeal) feminist theory of Elizabeth Grosz and Margrit Shildrick (in particular her theorization of the vulnerable body), and on the feminist posthumanist work of N. Katherine Hayles and Elaine Graham, this thesis focuses attention on issues of technological embodiment and the changing definition of what constitutes human corporeal experience and embodiment. Ultimately, the thesis proposes that feminist post-cyberpunk condemns the exploitation and control of, what Shildrick terms, the "visibly vulnerable" body and insists on recognizing the vulnerability of the flesh as a defining trait of what constitutes human being.</p> / Thesis / Doctor of Philosophy (PhD)

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