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[en] CHEMICAL PROCESSING OF A HIGH CARBON FECR ALLOY FINES AIMING TO OBTAIN CHROMIUM OXIDE / [pt] PROCESSAMENTO QUÍMICO DE FINOS DE UMA LIGA FECR ALTO CARBONO VISANDO A OBTENÇÃO DO ÓXIDO DE CROMODOUGLAS MARTINS TORRES 16 April 2019 (has links)
[pt] Ligas ferrosas são importantes insumos nos processos de obtenção de aços especiais. A obtenção de ligas Fe-Cr se dá principalmente por meio de dois processos, empregando-se como agentes redutores C ou Si, sendo o primeiro associado à síntese de ligas FeCrAC, e o segundo às ligas FeCrBC. Neste contexto, ligas do sistema Fe-Cr, com teor de Cr típico variando entre 45 a 95 por cento em massa, apresentam destaque, principalmente na fabricação de aços inoxidáveis. Durante processo de obtenção das referidas ligas, há considerável produção de finos, os quais podem ser reaproveitados mediante tratamento químico (piro e hidrometalúrgico) apropriado. No presente trabalho investigouse a extração de cromo de finos gerados durante a produção de uma liga Fe-Cr com alto teor de C. Para tanto foram realizadas ustulações nas temperaturas de 700, 800, 900 e 1000 graus Celsius com excessos de 100, 200, 300 e 400 graus Celsius NaOH e estequiométrico, 125, 150 e 200 graus Celsius de excesso de Mg(OH)2 em atmosfera oxidante, seguida de solubilização em meio aquoso e redução com H2O2 em diferente valores de pH, seguido-se da precipitação com NaOH em pH alcalino. Matéria prima, intermediários e produtos foram caracterizados por MEV/EDS, FTIR, DRX e ICP-OES. As recuperações de Cr em solução máximas alcançadas foram da ordem de 98 por cento, e a etapa de redução e precipitação em aproximadamente 95 por cento sugerindo que a rota de processamento químico proposta foi satisfatória no que tange à extração do cromo inicialmente presente. / [en] Ferrous alloys are important inputs in the process of obtaining special steels. The obtained Fe-Cr alloy is mainly by two processes, employing reducing agents such as C or Si, the first being associated with the synthesis of FeCrAC alloy and the second alloy to FeCrBC. In this respect, alloys of Fe-Cr system with varying Cr content typically between 45 to 95 percent by weight show prominence, particularly in the manufacture of stainless steel. During the process of obtaining these alloys, there is considerable production of fines which can be reused by appropriate chemical treatment (hydro-and pyro). In the present work we investigated the extraction of chrome fines generated during the production of a Fe-Cr alloy with high content of C. For both ustulações were performed at temperatures of 700, 800, 900 and 1000 Celsius degrees in excess of 100, 200, 300 and 400 percent stoichiometric NaOH and 125, 150 and 200 percent excess of Mg (OH) 2 in an oxidizing atmosphere, followed by solubilization in an aqueous medium and in H2O2 reduction with different pH values was followed by precipitation with-NaOH alkaline pH. Raw materials, intermediates and products were characterized by MEV/ EDS, FTIR, XRD and ICP-OES. The recoveries of Cr on maximal solution achieved were of the order of 98 percent, and the stage of reduction and precipitation by about 95 percent suggesting that the route of chemical processing proposal was satisfactory with regard to the extraction of chromium initially present.
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Análise de modelos de investimentos em distribuidoras de energia elétrica com foco no ativo posteMarques Filho, Ariel Cardoso 05 August 2014 (has links)
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Previous issue date: 2014-08-05 / A reestruturação do setor elétrico no Brasil foi marcada pelo processo de privatização das empresas estatais distribuidoras de energia. Na ocasião, o governo federal, através do Ministério de Minas e Energia, conferiu ao órgão regulador ANEEL – Agência Nacional de Energia Elétrica – a responsabilidade de criar normas regulatórias de controle das atividades das concessionárias de energia através de instrumentos como o contrato de concessão, resoluções. Essas regras estabelecem os critérios para as concessionárias realizarem os investimentos, e também como essas empresas recebem de volta os valores investidos, o que ocorre de 5 em 5 anos nas chamadas revisões tarifárias, quando a ANEEL audita todos os investimentos realizados pela concessionária e retorna o valor na tarifa de energia. Com o atual modelo, as empresas preferem realizar os maiores investimentos no último ano antes da revisão tarifária. Dessa forma, o modelo evita despesas de ordem financeira (juros) e de depreciação do ativo imobilizado da empresa. Sendo essas empresas privadas, as quais precisam maximizar seus lucros, é possível que ocorra um conflito entre a real necessidade de investimento e o ganho financeiro do investimento. Considerando essa problemática, o presente trabalho levantou dados e informações sobre postes, os quais compõem um dos principais itens do ativo de uma concessionária. Também se realizou um estudo de caso hipotético tendo como referência a concessionária AES Sul abrindo uma discussão acerca do tema para entender e concluir qual a melhor alternativa para decisão do investimento das concessionárias. Isto é, se pelo planejamento tradicional segundo modelos sugeridos por fontes bibliográficas para conservação e expansão do sistema elétrico, levando em consideração a robusteza da rede e a confiabilidade, ou pelo planejamento adaptado às regras regulatórias, levando em consideração as perdas financeiras de dinheiro no tempo e depreciação do ativo não remunerado. O trabalho utilizou como principal referência os modelos de investimentos abordados por Willis, a partir do quais foram desenvolvidas adaptações sobre os investimentos em postes para cada um dos modelos. Como resultado, se obtiveram informações em que foi possível concluir que existem alternativas de investimento que remetem à retornos distintos para a concessionária. / The restructuring of the electricity sector in Brazil was marked by the privatization of state-owned electricity distribution companies. On that occasion, the federal government, through Ministry of Mines and Energy, has given the regulator ANEEL - Brazilian Electricity Regulatory Agency - the responsibility to create regulatory standards control the activities of energy concessionaires through instruments such as the concession agreement, resolutions. These rules set out the criteria for utilities make the investments, and how these companies get back the amounts invested, which occurs in 5 five years in tariff revisions calls when ANEEL audits all investments made by the concessionaire and returns the value in the energy rate. With the current model, companies prefer to conduct the largest investments in the last year before the tariff review. Thus, the model avoids costs of a financial nature (interest) and depreciation of fixed assets of the company. As these private companies, which need to maximize your profits, which can occur a conflict between the real need for investment and financial gain investment. Considering this problem, this study collected data and information on poles, which make up one of the main items of the assets of a dealership. Also conducted a hypothetical case study with reference to the AES Sul dealership opening a discussion on the subject to understand and complete the best alternative to the investment decision of the concessionaires. That is, if the traditional planning models according suggested by literature sources for conservation and expansion of the electric system, taking into account the robustness and reliability of the network, or the adapted planning with regulatory requirements, taking into account the financial losses of money over time and asset depreciation unpaid. The study used as the main reference models of investments covered by Willis, from which adjustments were developed on investments in posts for each model. As a result, we obtained information on which it was concluded that there are investment options that refer to different returns to the dealership.
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Direito sancionador tributário : a necessária sistematização do direito de punir infrações tributáriasXavier, Leonardo Ventimiglia January 2017 (has links)
A doutrina jurídica, por conta do paulatino fenômeno da multiplicação das áreas de atuação do Estado, passou a subdividir o Direito em ramos autônomos. A medida busca dar conta da crescente complexidade do sistema, porquanto didaticamente distingue feixes normativos específicos voltados a regular determinadas matérias outorgando-lhes particularidades científicas e doutrinárias. Entretanto, ao longo do tempo, o conceito de autonomia foi muitas vezes exacerbado ao ponto de ser confundido com independência, como se cada ramo jurídico constituísse um segmento de conhecimento isolado, indiferente aos demais. Dentro deste quadro de multiplicidade normativa, especialmente na seara das obrigações tributárias, uma única conduta ilícita passou a ter a aptidão de atrair múltiplas sanções previstas por cada ramo autônomo do Direito sem qualquer espécie de ponderação. Não obstante, em qualquer hipótese ou subsistema em que se apresente o ilícito caracteriza-se como fenômeno que, a despeito de ostentar algumas particularidades passíveis de variação, pressupõe um ciclo idêntico. Ademais, é um só o sujeito que sofrerá o espectro punitivo de cada ramo jurídico e, por conseguinte, poderá responder inúmeras vezes pelo mesmo ato. Esta singularidade do ciclo ilícito, percebida com particular adequação pelo Direito espanhol e português, pressupõe contraposição através de um ius puniendi estatal uno. A aplicação de qualquer sanção deve seguir uma plêiade de pressupostos comuns aplicáveis ao Direito como um todo, e não a este ou aquele ramo de forma isolada. O presente trabalho, adotando como premissa metodológica o pensamento sistemático na Ciência do Direito, tem como escopo reaproximar a faceta punitiva do Direito Tributário brasileiro dos demais ramos jurídicos para, assim, outorgar-lhe unidade e ordenação. No desenvolvimento de tal objetivo serão: (a) trabalhados princípios constitucionais que, muito embora sejam costumeiramente elaborados sob as perspectivas individualizadas de cada um dos sub-ramos jurídicos, se prestam a uniformizar o direito de punir mediante o rompimento de fronteiras meramente didáticas; (b) apresentadas todas as modalidades punitivas previstas no direito brasileiro para os atos ilícitos relacionados às obrigações tributárias, o que perpassará pelas sanções de índole administrativa e também penal; e (c) propostas perspectivas de aplicação de institutos uniformizadores da prática sancionadora tributária brasileira, especialmente voltadas aos temas do concurso aparente de normas, concurso de infrações, vedação ao bis in idem, prejudicialidade entre a via jurisdicional criminal e a tributária, direito ao silêncio e a vedação ao efeito confiscatório na ação punitiva. / The legal doctrine, due the gradual multiplication of areas that the State has to act, began to subdivide the Law into autonomous branches. The measure seeks to simplify the increasing complexity of the system, building scientific and doctrinal peculiarities about specific normative bundles that are designated to regulate certain matters. However, over the time, the concept of autonomy was often exacerbated until the point of being confused with independence, as if each legal branch constituted a segment of isolated knowledge, indifferent to the others. In this framework of normative multiplicity, especially in the area of tax obligations, a single unlawful act can attract diferent sanctions provided by each autonomous branch of law without any kind of reasonability. Nonetheless, the illicit, despite having some peculiarities susceptible of variation, characterizes itself as a phenomenon which presupposes a similar cycle in any hypothesis or subsystem in which it appears. In addition, the subject who will suffer the punishment of each legal branch is the same, therefore, will respond numerous times by the same ilicit act. This feature of the unlawful act, perceived with particular suitability by Spanish and Portuguese law, presupposes opposition by a single punishment power of the state. The application of any sanction must follow a few common assumptions applied to the Law as a single system and not for each isolated branch. The present work, adopting the systematic thinking as methodological premise, seek to grant the unity and ordering of the punitive facet of Brazilian Tax Law by aproaching it of the other legal branches. To develop this objective we: (a) worked with constitutional principles that standardize the punishment right by overcoming didactic boundaries; (b) presented all punitive species in the Brazilian law for illicit acts related to tax obligations; and (c) proposed prospects for the application of standardization institutes in the Brazilian tax punishment practice, with special regard to issues of apparent competition of rules, competition of infractions, prohibition of double jeopardy, prejudiciality between criminal and tax jurisdictional channels, right of silence and the prohibition of confiscation in punitive action.
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Relación entre los estilos de aprendizaje y los estilos de pensamiento en estudiantes de maestría considerando las especialidades profesionales y el tipo de universidadDelgado Vásquez, Ana Esther January 2004 (has links)
Se plantea el estudio de la relación entre los estilos de aprendizaje y los estilos de pensamiento en estudiantes de maestría considerando el tipo de especialidad profesional y la universidad de procedencia. Los estilos de aprendizaje han sido analizados considerando la teoría del aprendizaje experiencial de Kolb y para los estilos de pensamiento se ha tomado en cuenta la teoría del autogobierno mental de Sternberg.
Los participantes fueron estudiantes de maestría de la Universidad Nacional Mayor de San Marcos y de la Universidad Ricardo Palma, los datos se obtuvieron utilizando el Inventario de Estilos de Aprendizaje de Kolb y el Cuestionario de Estilos de Pensamiento de Sternberg-Wagner Forma Corta. Se llevó a cabo el análisis de ítemes y se estableció la validez y confiabilidad de ambos instrumentos.
Se encontró que en el total de participantes el estilo de aprendizaje predominante es el Divergente, mientras que en los maestristas de la U.N.M.S.M. predomina el estilo Asimilador y en los alumnos la U.R.P predominan los estilos Acomodador y Divergente.
En cuanto a los estilos de pensamiento en los maestristas de ambas universidades, predominan los estilos Legislativo, Jerárquico, Local, Externo y Liberal. Se encontró que las frecuencias de las funciones, de las formas, de los niveles, del alcance y, de las inclinaciones del autogobierno mental de los estudiantes de maestría presentan diferencias significativas, tanto al considerar el total de participantes, como cada universidad de manera independiente.
De otro lado, se encontró que están asociadas la función del autogobierno mental y la universidad de procedencia. También se encontró una asociación significativa entre los estilos de aprendizaje y el tipo de especialidad profesional tanto en la muestra total, como en la U.N.M.S.M.
En cuanto a los estilos de pensamiento en los maestristas de ambas universidades, los resultados muestran la existencia de asociación entre las funciones del autogobierno mental y el tipo de especialidad profesional, asimismo, entre los niveles del autogobierno mental y el tipo de especialidad profesional, y finalmente entre el alcance del autogobierno mental y el tipo de especialidad profesional.
En la muestra de maestristas de la U.R.P. se encontró que están asociadas las funciones del autogobierno mental y el tipo de especialidad profesional y, los niveles del autogobierno mental y el tipo de especialidad profesional,
Finalmente, se encontró una asociación significativa entre los estilos de aprendizaje y las funciones del autogobierno mental en los alumnos de maestría de la U.N.M.S.M. y la U.R.P. / Tesis
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Observation et modélisation spatiale du climat aux échelles fines dans un contexte de changement climatiqueQuénol, Hervé 16 December 2011 (has links) (PDF)
Depuis la fin des années 1980, la communauté scientifique internationale s'intéresse au changement climatique global et s'interroge sur ses impacts futurs à l'échelle planétaire. Les différents rapports du GIEC (Groupe d'Experts Intergouvernemental sur l'Evolution du Climat) ont alerté la communauté internationale d'une augmentation de la température ainsi que de la fréquence et de l'intensité des aléas climatiques au niveau mondial. Même s'il existe de nombreuses incertitudes sur l'intensité du changement climatique et ses conséquences, l'amélioration de la fiabilité des Modèles de Circulation Générale du climat (MCG) et la corrélation positive entre les rejets de Gaz à Effet de Serre (GES) et l'augmentation des températures de ces dernières décennies montrent que le réchauffement global sera compris entre 2 et 6°C (selon les scénarios et les modèles) à l'horizon 2050-2100. Les impacts sur l'Homme ou les territoires, aux échelles globales et régionales, estimés à partir des MCG indiquent une augmentation des calamités climatiques telles que l'augmentation des sécheresses, de la fréquence et de l'intensité des épisodes de vagues de chaleur, etc. Ces évolutions pourront avoir de lourdes conséquences sur les écosystèmes et sur les sociétés notamment en matière de sécurité alimentaire et de malnutrition. Les résultats de ces programmes de recherche ont été obtenus principalement à partir de la modélisation numérique et grâce à des collaborations internationales entre les physiciens de l'atmosphère, les géophysiciens et les sciences de l'environnement. Mais très peu de géographes-climatologues ont participé à ces études. Pourtant, les géographes-climatologues, de part leurs compétences en terme d'analyse de données climatiques, de la connaissance du " terrain " et des méthodes de spatialisation de données climatiques basées sur les relations avec les caractéristiques environnementales (ex : méthodes géostatistiques, outils tels que la géomatique, ...) aux échelles régionales voire locales commencent à s'impliquer et à être impliqués dans les études d'impact du changement climatique que ce soit dans le domaine de la validation des sorties de modèles ou de l'adaptation à plus ou moins long terme. En effet, même si les simulations climatiques pour le futur abordent des échelles relativement larges, de réels progrès ont été réalisés au niveau de la résolution des sorties des modèles. C'est certainement sur la question de l'analyse et de la modélisation des climats régionaux et locaux que les géographes-climatologues pourront apporter leurs compétences pour l'amélioration des connaissances sur l'impact du changement climatique sur l'Homme et ses activités. Cela passe nécessairement par une démarche pluridisciplinaire avec notamment des collaborations au niveau scientifique, entre les physiciens de l'atmosphère, les sciences des techniques de l'information et de la communication (SIG), les agronomes, les sciences de la société ... et avec les " acteurs " (ex : politiques, agriculteurs, ...) sur le plan du transfert de l'information. Dans l'optique d'étudier l'impact du changement climatique aux échelles fines que ce soit au niveau des mesures ou de la modélisation, notre démarche consiste à installer des réseaux de mesures adaptées aux échelles fines qui permettront d'étudier les climats locaux en relation avec les activités humaines concernées et en fournissant des données à échelles fines qui permettront de participer à l'amélioration actuelle de la résolution spatiale des modèles notamment par l'intermédiaire de la validation des données. A plus long terme, ces réseaux (notamment ceux mis en place dans le cadre des programmes ANR-JC-TERVICLIM, GICC-TERADCLIM et ECORURB) auront pour vocation à être complétés et surtout être pérennisés afin d'obtenir une base de données climatiques adaptée aux échelles locales qui pourra être utilisée dans le futur pour réaliser des analyses en relation avec le changement climatique. Cette démarche scientifiques et les réseaux de mesures mis en place dans le cadre d'étude de climatologie appliquée font très souvent appel à une demande sociétale (ex : Plan Climat pour la lutte contre le changement climatique en ville, lutte contre les calamités agro climatiques, ...) sur les questions d'adaptation au changement climatique, à court, moyen et long terme. Pour ce travail d'Habilitation à Diriger des Recherches, seront présentés successivement : - la méthodologie mise en place pour l'analyse et la modélisation du climat aux échelles fines en montrant notamment comment ce type de démarche scientifique peut être un apport pour l'analyse de l'impact du changement climatique sur nos sociétés ; - des applications concrètes dans le domaine de la viticulture mondiale avec les programmes ANR-JC-TERVICLIM et GICC-TERADCLIM portant sur " l'observation et la modélisation du climat à l'échelle des terroirs viticoles dans le contexte du changement climatique ; - puis, les perspectives de recherches dans le domaine de l'analyse et de la modélisation climatique aux échelles fines et les adaptations possibles au changement climatique.
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Interaction of dissolved and colloidal substances with fines of mechanical pulp - influence on sheet properties and basic aspects of adhesionRundlöf, Mats January 2002 (has links)
No description available.
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Design of free flowing granular drains for groundwater containment applicationsBergerman, Martin 25 February 2011
Many geoenvironmental applications make use of granular drainage layers. Design guidelines for these drains recommend a granular soil that provides for filtration of the adjacent base soil. Filtration criteria have been developed through laboratory studies in which fine soils under a concentrated gradient of water are protected from erosion by a filter soil. The primary objective in these studies has been the geotechnical stability of earth-fill structures, while drainage was a secondary consideration. Granular drainage layers have therefore been constructed using fine sand. The subsequent migration of fine soil into these drains has resulted in significant loss in permeability.
The main research objective was to develop design criteria for granular drains to be used for long term operation in environmental applications. The secondary objective was to investigate the relationships between grain size distribution of drain materials and clogging by fines. This was done through a laboratory study where changes in permeability were measured in granular soils infiltrated with fines. Lastly, the effect of salinity on fines deposition was also investigated. The hypothesis of the current study is that coarser granular drains minimize the impact of clogging and provides a better alternative to traditional drain designs for long term environmental applications.
The laboratory study was performed with three granular drainage soils: a French Drain sand designed using the traditional filter design method, a coarser uniform sand, and a coarser graded sand with approximately 40% gravel sized particles. Three fine soils were used to infiltrate the drainage soils; however, their particle size distributions were not significantly different from one another. The results indicate that the permeability of all three drainage soils could be reduced by approximately one order of magnitude with continuous flow of a high concentration of fines (5 g/L). The permeabilities of the sands were reduced to a lesser extent with a lower concentration of fines. Permeabilities of the graded soils decreased more slowly with a lower concentration of fines, when considering pore volumes of flow. However, the rate of permeability decrease was ultimately influenced by the amount of fines delivered to the sample. A lower concentration of fines did not significantly slow the rate of permeability reduction in the uniform sand. All three sands retained a similar mass of fines (samples were split and fines content measured following each test). Salinity in the pore water did not significantly affect deposition, likely due to the fact that the fines contained a small amount of clay sized particles.
When considering that all three drainage soils became clogged with fines during the tests, the coarse soils maintained a relatively high permeability due to the fact that their pre-test permeabilities were high. This information, along with the results from the literature review, has led to the development of recommended new design criteria for granular drains to be used for long-term geoenvironmental applications. Test results from an earlier study found that dispersive soils subject to high gradients can be successfully protected by a filter coarser than the coarse graded soil used in the current study. It therefore follows that a granular soil intended for groundwater collection applications can be made to be coarser than the current accepted practice. A proposed granular drain design band is presented in the current study.
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Design of free flowing granular drains for groundwater containment applicationsBergerman, Martin 25 February 2011 (has links)
Many geoenvironmental applications make use of granular drainage layers. Design guidelines for these drains recommend a granular soil that provides for filtration of the adjacent base soil. Filtration criteria have been developed through laboratory studies in which fine soils under a concentrated gradient of water are protected from erosion by a filter soil. The primary objective in these studies has been the geotechnical stability of earth-fill structures, while drainage was a secondary consideration. Granular drainage layers have therefore been constructed using fine sand. The subsequent migration of fine soil into these drains has resulted in significant loss in permeability.
The main research objective was to develop design criteria for granular drains to be used for long term operation in environmental applications. The secondary objective was to investigate the relationships between grain size distribution of drain materials and clogging by fines. This was done through a laboratory study where changes in permeability were measured in granular soils infiltrated with fines. Lastly, the effect of salinity on fines deposition was also investigated. The hypothesis of the current study is that coarser granular drains minimize the impact of clogging and provides a better alternative to traditional drain designs for long term environmental applications.
The laboratory study was performed with three granular drainage soils: a French Drain sand designed using the traditional filter design method, a coarser uniform sand, and a coarser graded sand with approximately 40% gravel sized particles. Three fine soils were used to infiltrate the drainage soils; however, their particle size distributions were not significantly different from one another. The results indicate that the permeability of all three drainage soils could be reduced by approximately one order of magnitude with continuous flow of a high concentration of fines (5 g/L). The permeabilities of the sands were reduced to a lesser extent with a lower concentration of fines. Permeabilities of the graded soils decreased more slowly with a lower concentration of fines, when considering pore volumes of flow. However, the rate of permeability decrease was ultimately influenced by the amount of fines delivered to the sample. A lower concentration of fines did not significantly slow the rate of permeability reduction in the uniform sand. All three sands retained a similar mass of fines (samples were split and fines content measured following each test). Salinity in the pore water did not significantly affect deposition, likely due to the fact that the fines contained a small amount of clay sized particles.
When considering that all three drainage soils became clogged with fines during the tests, the coarse soils maintained a relatively high permeability due to the fact that their pre-test permeabilities were high. This information, along with the results from the literature review, has led to the development of recommended new design criteria for granular drains to be used for long-term geoenvironmental applications. Test results from an earlier study found that dispersive soils subject to high gradients can be successfully protected by a filter coarser than the coarse graded soil used in the current study. It therefore follows that a granular soil intended for groundwater collection applications can be made to be coarser than the current accepted practice. A proposed granular drain design band is presented in the current study.
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An investigation of the effects of polymer partitioning on fines retentionMiller, Charles E. 01 January 1989 (has links)
No description available.
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Elucidating the nature of bonding in mechanical pulpsLehtonen, Lauri Kalevi 11 1900 (has links)
Bond strength is classically
characterized into two separate factors; area of the bond and specific bond strength.
This separation is especially important in pulps that lack strength properties, and are
specifically used for their optical properties, such as mechanical pulps. In this
research the applicability of the Ingmansson and Thode method for distinguishing
between specific bonded area and specific bond strength in mechanical pulps is
studied. It is shown that the rigid, non-collapsable, nature of the mechanical pulp can
be overcome by press drying the sheets until they approach their 50% relative
humidity moisture content. Mechanical pulps have been assumed to operate in a
domain where fiber failure can be considered insignificant, and the bonded area to
tensile strength relationship is linear. In this study it was shown that most
commercial pulps operate in a significant fiber failure domain. However, it is shown
that pure fines and fines rich mechanical pulp better follow a linear bonded area to
tensile strength relationship rather than a non-linear (significant fiber failure) model,
suggesting that only the fiber fraction undergoes fiber failure and the finer fractions
predominantly bond failure. The Ingmansson and Thode method relies on the use of
scattering coefficient as a measure of specific surface area. It is shown that scattering coefficient is an accurate estimate of mechanical pulp specific surface area
at a constant wavelength of light, provided that the wavelength used to measure scattering coefficient is above the significant absorption limit.
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