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Produkce a charakterizace extracelulárních hydroláz z vybraných druhů plísní / Production and characteritzation of extracellular hydrolases from selected mouldsSkoumalová, Petra January 2011 (has links)
This diploma thesis is focused on study of potential production of extracellular hydrolytic enzymes. The theoretical part deals with characterization of selected hydrolytic enzymes, their catalytic properties, the possibility of extracellular hydrolase production by fungi and their applications. In experimental part production strains Aureobasidium pullulans, Fusarium solani and Phanerochaete chrysosporium were used. Productions of cellulase, amylase, xylanase, lipase, protease and lignin-degraded enzymes (laccase, manganese- dependent peroxidase, lignin peroxidase) were observed. Cultivations were carried out in submersed mode in mineral medium supplemented by waste co-substrates such as wheat bran, corn bran, rice bran and oat bran, sawdust, rice, apple fiber, egg pasta and egg-free pasta. Production of enzymes depended on the substrate type and time of cultivation. The highest cellulase, xylanase and amylase activities were measured in the first period of cultivation (3 to 7 day). Lignin-degraded enzymes and proteases were produced at the end of cultivation (7 to 10 days). Lipolytic activity was detected only in A. pullulans, where the activity increased with time of cultivation. The highest value was determined during cultivation on wheat bran (3.6 nmol/ml.min). The highest xylanase and celulase activity (170.3 nmol/ml.min, 248.0 nmol/ml.min) were determined during cultivation of F. solani on corn bran. The highest amylase activity (111.8 nmol/ml.min) was reported in P. chrysosporium during the cultivation on rice. The highest protease activity (68.0 nmol/ml.min) was determined in F. solani grown on wheat bran. The best producer of laccase was A. pullulans, the highest production was recorded for egg-free pasta (27.0 nmol/ml.min). The maximum lignin peroxidase activity (12.5 nmol/ml.min) was measured during the cultivation of F. solani on egg pasta, while the highest yield of Mn-dependent peroxidase (7.7 nmol/ml.min) was achieved during the cultivation of A. pullulans on wheat bran. Lignin-degraded enzymes behaved as inductive, while the other enzymes were produced in mineral medium too. Activity of cellulase in the mineral medium was in A. pullulans strain higher than in media with waste substrates. Enzymes produced into A. pullulans medium were purified by ultrafiltration, ion exchange chromatography and gel filtration.
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Etude de solutions innovantes de dépôts de superalliages et traitements de surface pour augmenter la résistance à l'usure et le comportement des moules métalliques de verrerie / Innovative solutions for superalloy coating or surface treatments in order to increase the service life of glass toolsRocancourt, Norman 26 September 2016 (has links)
Au cours des procédés de mise en forme du verre creux, les outillages de verrerie sont soumis à des conditions extrêmes avec des températures pouvant dépasser largement 650 °C. De plus, ces derniers sont exposés à des phénomènes d'abrasion sévères et à des réactions physico-chimiques complexes avec le verre fondu. Ceci est particulièrement accentué par les cycles thermiques dus aux contacts répétés avec le verre. L'objectif de ce travail de thèse est de proposer des solutions innovantes de dépôts de superalliages et/ou traitements de surface destinés à augmenter la durée de vie des outillages. Trois axes d'innovation sont présentés dans ce mémoire. Le premier concerne l'étude du dépôt de poudre composite Co/NiB par soudure PTA (Plasma Transfered Arc) sur des moules en alliage cuivreux. Le second est dédié à l'étude de la faisabilité technique d'un dépôt PVD (Physical Vapor Deposition) multicouche à gradient fonctionnel, présentant des caractéristiques intéressantes pour des applications verrières en termes de dureté et de stabilité thermique, sur des poinçons en acier AISI 431. Enfin, le troisième axe de recherche fait l'objet d'une analyse plus approfondie et concerne l'étude de la nitruration par implantation d'ions azotes multichargés, également sur un acier AISI 431. On observe après implantation une augmentation significative de la dureté (+ 240 %). Une approche multi-expérimentale et multi-échelle est alors proposée afin d'étudier la microstructure du matériau implanté ainsi que son évolution après un recuit de 1h à 650 °C de manière à anticiper le comportement du matériau en production, et de corréler ceci aux propriétés de dureté / Glass moulds have to withstand very high temperatures which can far exceed 650 °C during the glass forming process. They are exposed to very tough conditions such as abrasive wear and physico-chemical reactions, accentuated by thermal shocks due to high speed contact with hot glass melt. The aim of this work is to find innovative solutions for superalloy coating or surface treatments in order to increase the service life of glass tools. Three innovation projects are presented in this report. The first one is dedicated to PTA (Plasma Transferred Arc) welded coating of composite Co/NiB powder on copper alloy moulds. The second one is about technical feasibility of a multilayer PVD (Physical Vapor Deposition) coating with properties congruent to glass production in term of hardness and thermal stability, on AISI 431 plunger stainless steel. Last but not least, the third innovative project is about nitriding by ion implantation with multicharged nitrogen ions on AISI 431 stainless steel. We notice after ion implantation a significant hardness increase (+ 240 %). A multi-experimental and multi-scale approach was carried out in order to study the implanted material microstructure and its evolution after annealing at 650 °C during 1h to predict the material behavior during production and correlate it to hardness properties
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A Study of Ancient Egyptian Bread Moulds in Swedish Museums : A Typological and Documentative Study of Ancient Egyptian Middle Kingdom Bread Moulds / En Studie om Forntida Egyptiska Brödformar i Svenska Museum : En Typologisk samt Dokumenterande studie om Mellersta Rikets BrödformarAlzén, Felicia January 2024 (has links)
This thesis is a study of six Middle Kingdom bread moulds that are currently part of collections in Swedish museums. This thesis is also a discussion on the problems in early Egyptological documentation, with focus on sites such as Mirgissa, Abu Ghalib and Hawara. These are the rumoured places of origin of the six moulds that are part of the analysis for this thesis, three which are from the Gustavianum in Uppsala, and three which are from the Medelhavsmuseet in Stockholm. This author hopes to shed some new light on these objects and give them the documentation they deserve. By presenting two case studies on more modern excavations at the sites of Mersa Gawasis and Elephantine, this author will discuss what can be done to move forward in documenting objects in the future, regardless of if they are new finds or if they are a re-documentation of old ones. Furthermore, by using typology theories, the aim is to look at how documentation can get better. This author strives to place these moulds into a new light and bring forth some much-needed documentation to these types of bread moulds. / Denna uppsats är en studie gällande sex brödformar från Mellersta Riket, som förnärvarande finns i kollektioner i svenska museum. Denna Uppsats är också en diskussion om de problem som finns i tidig egyptologisk dokumentation, med fokus på områdena Mirgissa, Abu Ghalib samt Hawara. Dessa är de spekulerade platserna av ursprung för de sex formarna som är del av analysen för denna uppsats, tre som kommer från Gustavianum i Uppsala, och tre som kommer från Medelhavsmuseet i Stockholm. Denna författare hoppas på att ge nytt ljus till dessa objekt och ge dem den dokumentation som de förtjänar. Genom att presentera två fallstudier av mer moderna utgrävningar vid platserna Mersa Gawasis och Elephantine, kommer denna författare att diskutera vad som kan göras för att kunna gå framåt i dokumentation av objekt i framtiden, oavsett om de är nya objekt eller en om-dokumenten av gamla. Genom att använda typologiteorier, är huvudsyftet att kolla på hur dokumentation kan bli bättre. Denna författare strävar efter att placera dessa formar i ett nytt ljus, och bära fram en mycket behövlig dokumentation på dessa typer av brödformar.
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Fungal DNA, Mould, Dampness and Allergens in Schools and Day Care Centers and Respiratory HealthCai, Guihong January 2013 (has links)
Day care centers and schools are important environments for children, but few epidemiological studies exist from these environments. Mould, dampness, fungal DNA and allergens levels in these environments and respiratory health effects in school children were investigated in this thesis. In the day care centers studies, Allergen Avoidance Day care Centers (AADCs) and Ordinary Day care Centers were included. One third of the Swedish day care centers had a history of dampness or mould growth. Total fungal DNA levels were positively associated with risk construction buildings, reported dampness/moulds, rotating heat exchangers, linoleum floors and allergens (cat, dog, horse allergen) levels. The two school studies included secondary schools in Johor Bahru, Malaysia and elementary schools from five European countries (Italy, Denmark, Sweden, Norway, and France) (HESE-study). In Malaysia, 13 % of the pupils reported doctor-diagnosed asthma but only 4 % had asthma medication. The prevalence of wheeze in the last 12 months was 10 % in Malaysia and 13 % in the HESE-study. Cough and rhinitis were common among children in the HESE-study. There were associations between fungal DNA and reported dampness or mould growth. Fungal DNA levels and viable mould (VM) concentration in the classrooms were associated with respiratory symptoms (wheeze, rhinitis, cough, daytime breathlessness) in school children. In the HESE-study, associations were found between total fungal DNA, Aspergillus/Penicillium DNA and respiratory symptoms among children. Moreover, Aspergillus versicolor DNA and Streptomyces DNA were associated with respiratory symptoms in Malaysia and the HESE-study, as well as reduced lung function [forced vitality capacity (FVC) and forced expiratory volume in 1 second (FEV1)] among children in the HESE-study. In conclusion, fungal DNA and pet allergens were common in day care centers and schools and respiratory symptoms in school children were common. The associations between VM concentration and fungal DNA levels in the schools and respiratory health effects in school children indicated a need for improvement of these environments. Moreover, risk constructions should be avoided and buildings should be maintained to avoid dampness and microbial growth. Health relevance of microbial exposure and biodiversity needs to be further studied using molecular methods.
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Confecção e caracterização óptica e estrutural de lentes plásticas obtidas pelo processo de injeção / Production and characterization optic and estructural of plastic lens made by injection processSilva, Aparecido Rodrigues da 19 December 2002 (has links)
O propósito desse trabalho foi o de produzir lentes biconvexas pelo processo de injeção para serem utilizadas no ensino de óptica geométrica e de ciências nos níveis fundamental e médio. A importância de tal trabalho se justifica na carência de material experimental didático produzido no mercado nacional. Para atingir os objetivos propostos, foi necessário estudar o processo de injeção de termoplásticos e adequá-lo à produção de um componente óptico. No desenvolvimento do trabalho, foi projetado e confeccionado um molde para injeção das lentes, segundo especificações técnicas e apoiado em resultados obtidos através de simulações numéricas. Após a realização de testes de injeção, seguiu-se a caracterização das lentes obtidas através de parâmetros ópticos: transparência, birrefrigência, índice de refração, distância focal, raio de curvatura e FTM / The purpose of this work was the development and production of acrylic biconvex lens by injection process to be used in optical and science teaching at elementary and high schools. The importance of such work is based in the deficiency of experimental didactic material made in Brazil. In order to achieve the intended objective it was necessary to study the thermoplastic injection process and adapt it to the fabrication of an optical element. During the development of the work a mold was designed and constructed in according to technical specifications and based on results of numerical simulations. After the injection tests the lens were characterized by theirs optical parameters: transparency, birefringence, refraction index, focal distance, curvature radius and MFT
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Projeto e fabricação de moldes para prensagem isostática utilizando tecnologias CAD/CAE e prototipagem rápida. / Design and manufacturing of moulds in isostatic pressing using CAD/CAE technology and rapid prototyping.Canto, Rodrigo Bresciani 08 November 2002 (has links)
Apresenta uma metodologia para o projeto e fabricação de moldes para prensagem isostática de pó cerâmico (alumina) utilizando ferramentas computacionais CAD/CAE associadas à tecnologia de Prototipagem Rápida. O processo de prensagem isostática é simulado utilizando o método dos elementos finitos. Para a representação da compactação do pó cerâmico é utilizado o modelo de Drucker-Prager/cap e para a representação do comportamento do material elastomérico é utilizado o modelo hiperelástico de Mooney-Rivlin, ambos disponíveis no programa ABAQUS. Tal simulação visa obter o projeto do molde de forma mais rápida e precisa, ajustando-o até que se alcance um molde adequado para produzir um compacto com uma quantidade de sobrematerial ideal para o processo de usinagem a verde. Para isso utilizou-se como estudo de caso uma esfera cerâmica para implante de quadril. Um protótipo virtual do molde adequado obtido das simulações é então modelado e reproduzido em plástico ABS (Acrylonitrile Butadiene Styrene) pela tecnologia de Prototipagem Rápida FDM (Fused Deposition Modeling). Esse protótipo físico é a base para o desenvolvimento de matrizes rígidas e em silicone, que são utilizadas para a confecção da parte flexível do molde (matriz elastomérica) e de partes rígidas como a gaiola suporte obtidas por vazamento dos polímeros. Constatou-se a viabilidade da utilização da metodologia de projeto e fabricação do molde para prensagem isostática, considerando que as simulações mostraram-se bastante coerentes com os resultados experimentais obtidos de componentes prensados. / This work presents a methodology for the design and fabrication of ceramic powder isostatic pressing moulds using CAD and CAE tools and Rapid Prototyping. The isostatic pressing process was simulated using the finite element method. The compaction behavior of ceramic powder is described by the Drucker-Prager/cap constitutive model and the behavior of elastomeric material is described by the Mooney-Rivlin constitutive model within the commercial finite element software ABAQUS®. These simulations are required to adjust the mould design in order to suit the geometry of the compact and green machining allowance. For this study, it is used a case study consisting of pressing a ceramic sphere for hip implant stem. A virtual prototype was designed from the geometry obtained from the simulations and reproduced in Acrylonitrile Butadiene Styrene (ABS) polymer, using the Rapid Prototyping technology - Fused Deposition Modeling (FDM). Silicone moulds were obtained from the polymer prototype and used to aid in the making of the elastomeric bag and mould support cage. The methodology used in this investigation was validate considering that the simulations yield to a good agreement with measured manufactured components.
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Asthma and Respiratory Symptoms in Nordic Countries, Environmental and Personal Risk FactorsGunnbjörnsdóttir, María Ingibjörg January 2006 (has links)
<p>The overall aims of our studies were to identify risk factors for respiratory symptoms and asthma in indoor environment but even to look at some personal risk factors such as body mass index and gastroesophageal reflux. The study population is based on participants of the European Community Respiratory Health Survey I and II. </p><p> In the first study, water damage and visible moulds were reported in 7.4% and 17% of the homes respectively. The combination of water damage and visible moulds was independently associated with attacks of breathlessness when resting and after activity and also to long term cough. In the second study, the prevalence of nocturnal GER increased with higher BMI and the same pattern could be seen for habitual snoring. Reported onset of asthma, wheeze and night-time symptoms increased in prevalence along with the BMI gradient. In the multivariable analysis, obesity and nocturnal GER were independent risk factors for onset of asthma, wheeze and night-time symptoms. Habitual snoring was an independent risk factor for onset of wheeze and night-time symptoms, but not for onset of asthma. In the third study, a total of 18% of the subjects reported indoor dampness in the last 12 months and 27% of the subjects reported indoor dampness since the previous survey. Respiratory symptoms and asthma were significantly more prevalent in individuals exposed to indoor dampness and indoor dampness was a risk factor for respiratory symptoms and asthma after adjusting for possible confounders. Indoor dampness was an independent risk factor for onset of respiratory symptoms but not for asthma onset. Remission of respiratory symptoms was less likely to occur if subjects reported indoor dampness. In the fourth study, the lowest prevalence of atopy and the lowest levels of all indoor allergens, bacteria and moulds were found in Iceland. A positive association was found, between cat allergen exposure and asthma symptoms and between bronchial hyperresponsiveness and the amount of viable mould in indoor air.</p>
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Asthma and Respiratory Symptoms in Nordic Countries, Environmental and Personal Risk FactorsGunnbjörnsdóttir, María Ingibjörg January 2006 (has links)
The overall aims of our studies were to identify risk factors for respiratory symptoms and asthma in indoor environment but even to look at some personal risk factors such as body mass index and gastroesophageal reflux. The study population is based on participants of the European Community Respiratory Health Survey I and II. In the first study, water damage and visible moulds were reported in 7.4% and 17% of the homes respectively. The combination of water damage and visible moulds was independently associated with attacks of breathlessness when resting and after activity and also to long term cough. In the second study, the prevalence of nocturnal GER increased with higher BMI and the same pattern could be seen for habitual snoring. Reported onset of asthma, wheeze and night-time symptoms increased in prevalence along with the BMI gradient. In the multivariable analysis, obesity and nocturnal GER were independent risk factors for onset of asthma, wheeze and night-time symptoms. Habitual snoring was an independent risk factor for onset of wheeze and night-time symptoms, but not for onset of asthma. In the third study, a total of 18% of the subjects reported indoor dampness in the last 12 months and 27% of the subjects reported indoor dampness since the previous survey. Respiratory symptoms and asthma were significantly more prevalent in individuals exposed to indoor dampness and indoor dampness was a risk factor for respiratory symptoms and asthma after adjusting for possible confounders. Indoor dampness was an independent risk factor for onset of respiratory symptoms but not for asthma onset. Remission of respiratory symptoms was less likely to occur if subjects reported indoor dampness. In the fourth study, the lowest prevalence of atopy and the lowest levels of all indoor allergens, bacteria and moulds were found in Iceland. A positive association was found, between cat allergen exposure and asthma symptoms and between bronchial hyperresponsiveness and the amount of viable mould in indoor air.
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Feed grain improvement through biopreservation and bioprocessing : microbial diversity, energy conservation and animal nutrition aspects /Olstorpe, Matilda, January 2008 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 6 uppsatser.
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Untersuchungen zwischen Belastungen und Belastbarkeiten beim Herstellen tongebundener FormenAbdullah, Eva 27 August 2014 (has links) (PDF)
Im Rahmen der vorliegenden Arbeit wurde versucht, Gesetzmäßigkeiten zwischen Kenngrößen aus dem Formstofflabor und einer praxisnahen kleintechnischen Formanlage abzuleiten. Der Zweck besteht darin, einen Fehler bei der Formherstellung (insbesondere Ballenabrisse) zu vermeiden. Dazu wurden zahlreiche Untersuchungen sowohl im Formstofflabor als auch an der Versuchsanlage vorgenommen. Dies gleicht in ihrer Funktionsweise betrieblichen Formanlagen mit unterschiedlichen Verdichtungsmöglichkeiten. Bei den Untersuchungen wurden Formstoffzusammensetzungen variiert, konstruktive Änderungen an der Formmaschine vorgenommen und die Formballen mit unterschiedlichen Formschrägen versehen. Zur Beurteilung der Gebrauchstauglichkeit einer Grünsandform müssen die Beanspruchbarkeiten größer als die entstehenden Beanspruchungen oder zumindest gleich sein. Dazu wurde eine neue Methode zur Bestimmung der Ballenabrissneigung unter Einsatz eines variablen Gießereimodells entwickelt. Durch eine zielgerichtete Kombination der an der Formherstellung beteiligten Komponenten: Formstoff, Formmaschine und Formprozess ließen sich qualitätsgerechte Formen herstellen und die Ergebnisse erfolgreich auf die betriebliche Praxis übertragen.
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