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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Impregnação de peças de osso bovino com poli(metilmetacrilato) : um novo material para o design de produto

Roese, Pedro Barrionuevo January 2009 (has links)
O presente trabalho teve como objetivo obter um material compósito a partir da impregnação de peças de osso bovino com um monômero seguido da polimerização deste, resultando assim em um material com menor absorção de água e inchamento quando comparado ao osso em seu estado natural. O tratamento de impregnação realizado foi adaptado de tratamentos tipicamente empregados na madeira e, para tal, foi realizada uma ampla revisão bibliográfica com o objetivo de determinar as diferenças entre a estrutura química e a microestrutura do osso e da madeira. A partir da revisão bibliográfica, determinou-se que as melhores chances de se obter bons valores para os parâmetros de eficiência anti-inchamento (%EAI) e eficiência na exclusão de umidade corrigida (%EEUC) residiam em aplicar ao osso um tratamento de impregnação com metilmetacrialto (MMA) utilizando vácuo ou pressão e metanol ou ácido acrílico (AA) como promotores de difusão. Determinou-se a composição média das peças de osso quanto ao teor de umidade, de mineral e de gordura e os resultados mostraram que as amostras de osso empregadas eram bastante homogêneas. Então, foi estudada a influência do vácuo, de pressão positiva e da concentração dos promotores de difusão na impregnação do osso com MMA. Os resultados mostraram que o uso de vácuo, de metanol a 20% v:v e AA a 5% v:v aceleram a absorção de MMA pelo osso permitindo assim obter um maior teor de impregnante no compósito. As peças de osso foram então impregnadas com MMA e este foi polimerizado in situ para a obtenção do material compósito, utilizando peróxido de benzoíla como iniciador e temperaturas de 90ºC. O material resultante foi caracterizado em ensaios de absorção de água e inchamento e analisado por microscopia óptica e eletrônica de varredura. Os compósitos obtidos utilizando metanol 20% v:v como promotor de difusão apresentaram os melhores resultados com %EAI = 22,1% e %EEUC = 35,1%, comparados ao osso não impregnado. / This work aimed to obtain a composite material from the impregnation of bovine bone slabs with a monomer, followed by monomer polymerization, yielding a material with lower water absorption and swelling compared to untreated bone. The impregnation carried out was adapted from treatments which are typically employed to wood and, to make that possible, a broad review was carried out to determine the differences between the chemical and microstructural composition of wood and bone. From the review, it was determined that the best possibilities to obtain high values for the anti swelling efficiency (%ASE) and moisture exclusion efficiency (%MEE) parameters could be reached through the impregnation of the bone slabs with methylmetacrylate (MMA) employing pressure and methanol and acrylic acid (AA) as diffusion promoters. Before starting impregnation procedures, the mean composition of the bone slabs regarding moisture content, mineral content and fat content was determined. Results showed that the bone slabs composition was quite homogeneous. Then, the influence of vacuum, 2 bar pressure and methanol and AA concentration in the absorption of MMA by the bone slabs. The results pointes that vacuum and methanol 20% v:v and AA 5% v:v speeds up the MMA absorption by bone, thus, making possible to obtain composites with higher impregnant amounts. Once the optimized impregnation conditions were found, boné slabs were impregnated with MMA in such conditions and then it was polymerized in situ with benzoyl peroxide as initiator and 90ºC temperature. The resulting material was characterized regarding water absorption and swelling and was analyzed through optical and electronic microscopy. Results showed that the composites obtained with methanol as diffusion promoter presented the best performance with %ASE = 22.1% and %MEE = 35.1%.
2

Impregnação de peças de osso bovino com poli(metilmetacrilato) : um novo material para o design de produto

Roese, Pedro Barrionuevo January 2009 (has links)
O presente trabalho teve como objetivo obter um material compósito a partir da impregnação de peças de osso bovino com um monômero seguido da polimerização deste, resultando assim em um material com menor absorção de água e inchamento quando comparado ao osso em seu estado natural. O tratamento de impregnação realizado foi adaptado de tratamentos tipicamente empregados na madeira e, para tal, foi realizada uma ampla revisão bibliográfica com o objetivo de determinar as diferenças entre a estrutura química e a microestrutura do osso e da madeira. A partir da revisão bibliográfica, determinou-se que as melhores chances de se obter bons valores para os parâmetros de eficiência anti-inchamento (%EAI) e eficiência na exclusão de umidade corrigida (%EEUC) residiam em aplicar ao osso um tratamento de impregnação com metilmetacrialto (MMA) utilizando vácuo ou pressão e metanol ou ácido acrílico (AA) como promotores de difusão. Determinou-se a composição média das peças de osso quanto ao teor de umidade, de mineral e de gordura e os resultados mostraram que as amostras de osso empregadas eram bastante homogêneas. Então, foi estudada a influência do vácuo, de pressão positiva e da concentração dos promotores de difusão na impregnação do osso com MMA. Os resultados mostraram que o uso de vácuo, de metanol a 20% v:v e AA a 5% v:v aceleram a absorção de MMA pelo osso permitindo assim obter um maior teor de impregnante no compósito. As peças de osso foram então impregnadas com MMA e este foi polimerizado in situ para a obtenção do material compósito, utilizando peróxido de benzoíla como iniciador e temperaturas de 90ºC. O material resultante foi caracterizado em ensaios de absorção de água e inchamento e analisado por microscopia óptica e eletrônica de varredura. Os compósitos obtidos utilizando metanol 20% v:v como promotor de difusão apresentaram os melhores resultados com %EAI = 22,1% e %EEUC = 35,1%, comparados ao osso não impregnado. / This work aimed to obtain a composite material from the impregnation of bovine bone slabs with a monomer, followed by monomer polymerization, yielding a material with lower water absorption and swelling compared to untreated bone. The impregnation carried out was adapted from treatments which are typically employed to wood and, to make that possible, a broad review was carried out to determine the differences between the chemical and microstructural composition of wood and bone. From the review, it was determined that the best possibilities to obtain high values for the anti swelling efficiency (%ASE) and moisture exclusion efficiency (%MEE) parameters could be reached through the impregnation of the bone slabs with methylmetacrylate (MMA) employing pressure and methanol and acrylic acid (AA) as diffusion promoters. Before starting impregnation procedures, the mean composition of the bone slabs regarding moisture content, mineral content and fat content was determined. Results showed that the bone slabs composition was quite homogeneous. Then, the influence of vacuum, 2 bar pressure and methanol and AA concentration in the absorption of MMA by the bone slabs. The results pointes that vacuum and methanol 20% v:v and AA 5% v:v speeds up the MMA absorption by bone, thus, making possible to obtain composites with higher impregnant amounts. Once the optimized impregnation conditions were found, boné slabs were impregnated with MMA in such conditions and then it was polymerized in situ with benzoyl peroxide as initiator and 90ºC temperature. The resulting material was characterized regarding water absorption and swelling and was analyzed through optical and electronic microscopy. Results showed that the composites obtained with methanol as diffusion promoter presented the best performance with %ASE = 22.1% and %MEE = 35.1%.
3

Impregnação de peças de osso bovino com poli(metilmetacrilato) : um novo material para o design de produto

Roese, Pedro Barrionuevo January 2009 (has links)
O presente trabalho teve como objetivo obter um material compósito a partir da impregnação de peças de osso bovino com um monômero seguido da polimerização deste, resultando assim em um material com menor absorção de água e inchamento quando comparado ao osso em seu estado natural. O tratamento de impregnação realizado foi adaptado de tratamentos tipicamente empregados na madeira e, para tal, foi realizada uma ampla revisão bibliográfica com o objetivo de determinar as diferenças entre a estrutura química e a microestrutura do osso e da madeira. A partir da revisão bibliográfica, determinou-se que as melhores chances de se obter bons valores para os parâmetros de eficiência anti-inchamento (%EAI) e eficiência na exclusão de umidade corrigida (%EEUC) residiam em aplicar ao osso um tratamento de impregnação com metilmetacrialto (MMA) utilizando vácuo ou pressão e metanol ou ácido acrílico (AA) como promotores de difusão. Determinou-se a composição média das peças de osso quanto ao teor de umidade, de mineral e de gordura e os resultados mostraram que as amostras de osso empregadas eram bastante homogêneas. Então, foi estudada a influência do vácuo, de pressão positiva e da concentração dos promotores de difusão na impregnação do osso com MMA. Os resultados mostraram que o uso de vácuo, de metanol a 20% v:v e AA a 5% v:v aceleram a absorção de MMA pelo osso permitindo assim obter um maior teor de impregnante no compósito. As peças de osso foram então impregnadas com MMA e este foi polimerizado in situ para a obtenção do material compósito, utilizando peróxido de benzoíla como iniciador e temperaturas de 90ºC. O material resultante foi caracterizado em ensaios de absorção de água e inchamento e analisado por microscopia óptica e eletrônica de varredura. Os compósitos obtidos utilizando metanol 20% v:v como promotor de difusão apresentaram os melhores resultados com %EAI = 22,1% e %EEUC = 35,1%, comparados ao osso não impregnado. / This work aimed to obtain a composite material from the impregnation of bovine bone slabs with a monomer, followed by monomer polymerization, yielding a material with lower water absorption and swelling compared to untreated bone. The impregnation carried out was adapted from treatments which are typically employed to wood and, to make that possible, a broad review was carried out to determine the differences between the chemical and microstructural composition of wood and bone. From the review, it was determined that the best possibilities to obtain high values for the anti swelling efficiency (%ASE) and moisture exclusion efficiency (%MEE) parameters could be reached through the impregnation of the bone slabs with methylmetacrylate (MMA) employing pressure and methanol and acrylic acid (AA) as diffusion promoters. Before starting impregnation procedures, the mean composition of the bone slabs regarding moisture content, mineral content and fat content was determined. Results showed that the bone slabs composition was quite homogeneous. Then, the influence of vacuum, 2 bar pressure and methanol and AA concentration in the absorption of MMA by the bone slabs. The results pointes that vacuum and methanol 20% v:v and AA 5% v:v speeds up the MMA absorption by bone, thus, making possible to obtain composites with higher impregnant amounts. Once the optimized impregnation conditions were found, boné slabs were impregnated with MMA in such conditions and then it was polymerized in situ with benzoyl peroxide as initiator and 90ºC temperature. The resulting material was characterized regarding water absorption and swelling and was analyzed through optical and electronic microscopy. Results showed that the composites obtained with methanol as diffusion promoter presented the best performance with %ASE = 22.1% and %MEE = 35.1%.
4

BioStudio : do tecido plano ao cultivo de tecidos vivos

Abreu, Breno Tenório Ramalho de 10 July 2015 (has links)
Dissertação (mestrado)—Universidade de Brasília, Instituto de Artes, Departamento de Desenho Industrial, Programa de Pós-graduação em Design, 2015. / Submitted by Tania Milca Carvalho Malheiros (tania@bce.unb.br) on 2015-11-30T15:58:10Z No. of bitstreams: 1 2015_BrenoTenórioRamalhodeAbreu.pdf: 16534977 bytes, checksum: 8114b93fa50a51c5e8503ab8ede019cc (MD5) / Approved for entry into archive by Patrícia Nunes da Silva(patricia@bce.unb.br) on 2016-01-25T14:01:47Z (GMT) No. of bitstreams: 1 2015_BrenoTenórioRamalhodeAbreu.pdf: 16534977 bytes, checksum: 8114b93fa50a51c5e8503ab8ede019cc (MD5) / Made available in DSpace on 2016-01-25T14:01:47Z (GMT). No. of bitstreams: 1 2015_BrenoTenórioRamalhodeAbreu.pdf: 16534977 bytes, checksum: 8114b93fa50a51c5e8503ab8ede019cc (MD5) / O Biodesign procura empregar organismos vivos na composição de produtos e serviços oferecidos a sociedade. Baseado nesta ideia, e diante da necessidade de trabalhos que promovam inovação em processos de fabricação têxtil na área de tingimento e design de superfícies, esta pesquisa interdisciplinar surge com o objetivo de relacionar o Biodesign e o vestuário por meio de testes de coloração de tecidos orgânicos e criação de estampas utilizando linhagens de actinobactéria. Para isto, foi utilizado uma metodologia exploratória separada em laboratórios de cor, superfície e APP (teste de formas e experimentação). Após obtidas as colorações e estampas/colônias de actinobactérias, os tecidos foram submetidos a lavagem e passagem. Posteriormente serão estudadas melhores técnicas de fixação da estampa após a lavagem, assim como é de interesse deste projeto estudar e purificar os pigmentos produzidos por estas linhagens de actinobactérias, e a interação entre estas estampas produzidas e a pele do usuário, assim como análises morfológicas, microscópicas e de patogenicidade das linhagens que geraram melhores resultados. ______________________________________________________________________________ ABSTRACT / Biodesign employs living organisms in the composition of products and services offered to society. Based on this idea, and faced with the need to promote innovation in manufacturing processes in textile dyeing and surface design, this interdisciplinary research appears with the objective to relate Biodesign and fashion through the staining of natural fibers and creation of patterns using actinobacteria strains. For this purpose, it was done an exploratory laboratory methodology separated on laboratories of color, surface, and APP (forms and experimentation test). After obtaining the dyes and patterns/colonies, tissues were washed and ironed. Later, this work pretend to study the best adherance techniques, and is of interest of this project to purify the pigments produced by these strains of actinomycetes, and study the interaction between these products and the skin of the user, as well as do morphological analyzes, microscopy and pathogenicity tests of the strains that have generated better results.
5

Control of Dynamic DNA Origami Mechanisms Using Integrated Functional Components

Miller, Carl A. 20 May 2015 (has links)
No description available.
6

DNA Origami Mechanisms and Machines

Marras, Alexander Edison 25 July 2013 (has links)
No description available.
7

Pleurotus ostreatus production on Cannabis sativa, L. (Industrial Hemp) Residues for Edible Mushrooms and Mycelium-based Composites

Reiss II, Matthew William 14 August 2022 (has links)
The current anthropogenic practices of generating single-use waste streams in agriculture, forestry and manufacturing industries have created a host of environmental health problems. Humankind's reliance on non-renewable resources for the production of food and materials, and its current approach to product design and development, are clearly unsustainable. One mitigation strategy to reducing industrial and municipal solid waste, as well as environmental pollution, can be found in using white rot fungi to valorize our planet's most abundant and regenerative natural resource – plant biomass containing lignocellulose. From residual dry plant matter, white rot fungi can be employed through a solid-state fermentation process to produce a variety of edible, nutrient-dense saprotrophic mushrooms in addition to biologically augmented composite materials. Under the framework of the circular economy, agricultural and forestry byproducts with fibers containing lignin, cellulose and hemicellulose may be used as a feedstock for the production of both food and biomaterials – keeping plant biomass revolving through multiple cycles of use and reuse for a variety of product outputs that are biodegradable and help to sequester carbon. In this study, mushrooms were grown on a variety of lignocellulosic substrates derived from agricultural and forestry residues. Hemp-based substrates performed the best of the feedstocks with regard to mushroom yield and mycelium colonization time. Additionally, a number of mycelium composite products were designed and fabricated in this study using residual lignocellulosic plant biomass, including: insulation bricks, acoustical panels, and biodegradable planter pots. In particular, spent mushroom substrate containing hemp hurd and other agricultural and forestry residues showed significant potential in upcycling lignocellulosic plant biomass for the production of both mushrooms and mycelium materials. Regenerative design practices demonstrated how food and materials can be generated from the same lignocellulosic feedstock; therefore, reducing waste, circulating products and materials, and ultimately regenerating nature. / Master of Science / Environmental pollution and natural resource scarcity have encouraged exploration into using biologically based materials for the production of more ecologically friendly products. By valorizing the Earth's most abundant, renewable natural resource for the production of food and materials– dry plant matter containing lignocellulose – waste is reduced, carbon is stored, and materials can remain upcycled through multiple generations of production. Lignocellulosic residues – natural fibers containing the biopolymers lignin, cellulose and hemicellulose – have recently been given increased attention due to their ability to be aggregated and grown into low-cost, lightweight materials using white rot fungi. Mushroom farming has historically valorized lignocellulosic agricultural and forestry residues to grow an edible, nutrient-dense food crop. This thesis investigates the potential of various agricultural and forestry residues for the production of mushrooms and mycelium-based lignocellulosic composites. Furthermore, this study explores the utilization of spent mushroom substrate for the production of several mycelium-based composite products within the framework of the circular economy. Hemp-based substrates demonstrated significant potential in both mushroom production and mycelium composite fabrication, outperforming other agricultural residues in this study with regard to mushroom yield and speed of mycelial growth of Pleurotus ostreatus. More research into the tunable lignocellulosic substrate compositions will continue to help advance mushroom production and mycelium-based composite generation as environmentally friendly materials and production practices continue to gain interest.
8

Biological Affordances & Aesthetics of Interaction / Equilibrium - Biological wearable for emotional wellbeing

Ivan, Kunjasic January 2020 (has links)
If you could trap a moment of painful sorrow or a deep joy, what form would you like to keep? This project is exploring how designing with biology can allow new sets of affordances and ways of expressing and interacting with the artifacts. Hence to this idea, the researcher is exploring the concept of crystalizing tears and turning them to gold, both metaphorically and literally. Showcasing how wearable made of living things could allow us more humane, poetic, and symbiotic relationships, compare to transactional interactions we currently have with wearables based on computation. As the outcome of the project, the researcher uses a biochemical phenomenon to commemorate chapters in life. Beyond that, the researcher is opening a field of what could be possible in the context of designing with biology and biological matters, how we are going to use them, and what kind of relationship we could build, as we move from machines to organisms, from pixels to cells. In its core, the researcher desired to show that Interaction designers must become material researchers, rather than inhabiting in the realm of familiar mediums. And this is what this thesis is all about, and hopefully, it does not stop there.
9

Designing a Novel Prototype for Efficient Blood Sampling and Storage: An Experimental Study on Plasma Separation Cards

Lundgren, Philip, Ghebreyesus, Adam January 2024 (has links)
The aim of this study is to optimize the storage and shipping processes of Plasma Separation Cards (PSC) by developing a novel prototype designed to reduce manual labore and ensure sample integrity. An experimental design was employed to address current limitations in PSC handling. These limitations include labor-intensive processes and potential sample degradation. In this approach rigorous testing was done to evaluate the prototype's performance in various environments and different materials. The research in this study include lab testing of samples stored in the prototype, assessment of different storage conditions and analysis of shipping processes. The main research question was: “How can a prototype for PSC storage be optimized to reduce manual labor in PSC handling while ensuring sample integrity during storage and shipping?”. To answer this question the prototype was tested for its effectiveness in reducing storage space and facilitating automated handling The findings of this study show that the prototype that was created can significantly reduce the required storage space while still being usable by liquid handling robots. During the study it was noted that minor misalignment issues were present due to the limitations of the type of 3D printers used. These issues could be addressed with more precise printing technologies such as Stereolithography (SLA) or Selective Laser Sintering (SLS). Both materials used in this study, PLA (Polylactic acid) and PETG (Polyethylene Terephthalate Glycol) materials were found suitable for storing PSC samples under most conditions. However, the measurements for the samples with PLA indicated limitations at 65 °C under certain conditions, making PETG a safer choice under higher temperature. The study contributes to the field by providing an innovating solution for PSC sampling that is scalable. This enhances the possibility for remote monitoring end predictive diagnostics. The prototype indicates a promising direction for future research and application and medical diagnostics by improving operational efficiency while aligning with sustainability goals. This study explores the following aspects: sample handling, storage and shipping. The practical implication includes reduced manual labor, minimized human error and increased efficiency for these aspects.

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