Dissertations / Theses on the topic 'Natural building materials'
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Ferreira, Pinto Da Silva Carla Florbela. "Interactions between volatile organic compounds and natural building materials." Thesis, University of Bath, 2017. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760948.
Full textO'Rourke, Eamonn Christopher. "Natural building in South Africa : assessing the niche-regime relationship through a 'latent niche' mediation." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96704.
Full textENGLISH ABSTRACT: In this thesis I examine the natural building movement in South Africa in an attempt to determine the systemic influences that appear to confine it to a small market operating at the very edge of the mainstream building sector. I make use of the conceptual framework of the multi-level perspective to explore the interrelationships between natural building as a technological niche and the mainstream building sector as the dominant regime. I extend the concept of a technological niche by appending the term 'latent' to form the term 'latent technological niche', to describe a technology with sustainability credentials that fails to break into the mainstream market, despite achieving technological maturity and constant though minimal market share. The research objectives of this thesis are to: identify pathways for the natural building niche to move beyond its latent state; to determine how the translations of natural building practices to the building sector might occur; and how this might transform the building sector regime. I explore how action research involving knowledge sharing between multi-stakeholder, niche and regime actors might stimulate debate and subsequent action to overcome entry barriers; and serve as a catalyst to advance a latent technological niche beyond its confined market. I present an action research method, a 'latent technological mediation', of facilitated 1st and 2nd order social learning. This is used as a mechanism of tapping into the immediate knowledge of actors in the socio-technical regime. The purpose being to identify the external forces and internal processes of a latent technological niche. The status of a latent technological niche is assessed by comparing these processes in the context of external forces against seven processes, presented in this thesis. These seven processes are considered crucial for a technology to break into the mainstream market and are adapted from the internal processes of success, described in the literature on strategic niche management and the characteristics of a successful 'bounded socio-technical experiment' (BSTE) described in the conceptual work on BSTE's. The potential for natural building systems to enter the mainstream building sector, particularly in South Africa, is used as a case study to apply the latent technological mediation method. The findings of this research suggest that the mainstream building sector is undergoing a transition following the path of socio-techical transformation. The uncertainty introduced by the parallel system of informal settlement, which may drive transition along the more dramatic technological substitution or de-alignment and re-alignment transition pathways is briefly explored.
AFRIKAANSE OPSOMMING: In hierdie tesis ondersoek ek die natuurlike gebou beweging in Suid-Afrika in 'n poging om die sistemiese invloede te bepaal, wat neig om dit te beperk tot 'n klein mark teen die rand van die hoofstroom gebou sektor. Ek maak gebruik van die konseptuele raamwerk van die multi-vlak perspektief om die onderlinge verband tussen natuurlike geboue, as 'n tegnologiese nis, en die hoofstroom gebou sektor, as die dominante regime, te verken. Ek brei die konsep van 'n tegnologiese nis uit, deur die aanbring van die word 'latente' om die term 'latente tegnologiese nis' te vorm. 'n Latente tegnologie nis het volhoubaarheid potensiaal maar slaag nie daarin om in die hoofstroom mark in te breek nie, ten spyte van die bereiking van tegnologiese volwassenheid en 'n konstante maar minimale mark aandeel. Die navorsing doelwitte van hierdie tesis is om: roetes te identifiseer waarlangs die natuurlike gebou nis buite sy latente toestand kan beweeg; om te bepaal hoe die 'vertalings' van natuurlike gebou praktyke aan die gebou sektor kan voorkom; en hoe dit die gebou sektor regime kan verander. Ek bestudeer hoe aksie navorsing waarby kennis tussen verskeie belanghebbendes, nis en regime betrokkenes gedeel is, kan debatteer en die daaropvolgende aksie stimuleer inskrywing hindernisse te oorkom; en dien as 'n katalisator om 'n latente tegnologiese nis te bevorder buite sy beperkte mark. Ek bied 'n aksie-navorsing metode, 'n 'latente tegnologiese bemiddeling' van gefasiliteerde 1st en 2de order sosiale leerervaring aan. Dit dien as 'n meganisme van deling in die onmiddellike kennis van die spelers in die sosio-tegniese regime. Die doel is om die eksterne kragte en interne prosesse van 'n latente tegnologiese nis te identifiseer. Die status van 'n latente tegnologiese nis is beoordeel deur hierdie prosesse te vergelyk in die konteks van eksterne kragte teen sewe prosesse, wat in hierdie tesis aangebied is. Hierdie sewe prosesse word beskou as noodsaaklik vir 'n tegnologie om in die hoofstroom mark in te breek en is aangepas uit die interne prosesse van sukses, soos beskryf in die literatuur oor strategiese nis bestuur en die eienskappe van 'n suksesvolle 'begrensde sosio-tegniese eksperiment' (BSTE) beskryf in die konseptuele literatuur oor BSTE. Die potensiaal vir natuurlike gebou stelsels om die hoofstroom gebou sektor te betree, veral in Suid-Afrika, word gebruik as 'n gevallestudie om die latente tegnologiese bemiddeling metode toe te pas. Die bevindinge van die navorsing dui daarop dat die hoofstroom gebou sektor 'n verandering ondergaan op die pad van n sosio-tegniese transformasie. Die onsekerheid veroorsaak deur die parallelle informele nedersetting, wat 'n meer dramatiese tegnologiese substitusie, of ontsporing en herbelyning kan veroorsaak, word kortliks ondersoek.
Dai, Dan, and Xiuying Tang. "Transitioning towards sustainable management of building materials in China." Thesis, Blekinge Tekniska Högskola, Avdelningen för maskinteknik, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2666.
Full textWęcławski, Bartosz Tomasz. "The potential of bast natural fibres as reinforcement for polymeric composite materials in building applications." Thesis, Brunel University, 2015. http://bura.brunel.ac.uk/handle/2438/11670.
Full textde, las Heras Reverte Víctor. "Evaluation of natural materials in Sustainable Buildings : A potential solution to the European 2050 long-term strategy." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-300115.
Full textGudmundsson, Kjartan. "Alternative approaches to moisture transfer in building materials : the use of natural stable isotopes and tracer gas." Licentiate thesis, KTH, Byggvetenskap, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-34502.
Full textFonseca, Leandro Milhomens da. "Avaliação da radioatividade natural em tintas de uso comercial no Brasil." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-15062016-152051/.
Full textNatural radioactivity in soils, rocks and construction materials, due to 40K and the natural series of 232Th and 238U, is the main contribution to external exposure in mankind. In this work, activity concentrations of 226Ra (238U serie), 232Th and 40K were determined for 50 white latex wall paints samples, commercialized in Brazil, namely 15 Economic quality samples, 15 Standard quality samples and 20 Premium quality samples and for a single titanium dioxide sample. The samples were tightly sealed and stored for a minimum period of 30 days, to reach the radioactive secular equilibrium from 238U and 232Th series, then measured by high resolution gamma ray spectrometry. The activity concentration was determined using the weighted average concentrations of 214Pb and 214Bi for 226Ra and 228Ac, 212Pb and 212Bi for 232Th. The 40K activity concentration was determined by its single transition of 1460.8 keV. Self attenuation correction factors of the samples whose densities are higher than 1.0 g.cm-3, were determined and used to make the necessary corrections. The radiological indices radium equivalent activity (Raeq), activity concentration index (Iγ), internal exposure risk index (Hin) and external exposure risk index (Hex) and also the absorbed dose rate (D) and annual effective dose (Def) were calculated from the activity concentrations of 226Ra, 232Th and 40K. The activity concentration values for 226Ra ranged from under the minimum detectable activity to 38.7 Bq.kg-1, for 232Th from under the minimum detectable activity to 101.2 Bq.kg-1 and for 40K from under the minimum detectable activity to 256 Bq.kg-1. Raeq ranged from 1.41 Bq.kg-1 to 203 Bq.kg-1, Iγ ranged from 0.0047 to 0.720, Hin from 0.0076 to 0.653 and Hex from 0.0038 to 0.549. The absorbed dose rate ranged from 0.170 nGy.h-1 and 21.3 nGy.h-1 and the annual effective dose ranged from 0.83 μSv and 104.2 μSv. The results show that the activity concentrations of the wall paints studied in this work are below the recommended limits by Hassan et al. for Raeq (370 Bq.kg-1), by European Commission for Iγ (limit of 2 for superficial materials) and by the Organisation for Economic Co-operation and Development for Hin and Hex (both with limit of 1), for all the 50 samples, assuring the safety of these wall paints with respect to radiological protection.
Persson, Staffan. "Indigenous Materials in Modern Buildings : for low energy houses in West Africa." Thesis, Uppsala universitet, Byggteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-224892.
Full textBurkina Faso är ett av de fattigaste länderna i världen. Som ett kustlöst land beläget i Västafrika har det ett extremt varmt klimat. Temperaturer över 45°C är inte ovanligt och det är ett nästan konstant behov av att kyla byggnader för att behålla ett behagligt inneklimat. Idag byggs det två typer av byggnader i Burkina Faso; de traditionella lerhusen och de mer moderna husen med väggar av cementstenar och plåttak. Cementväggarna har ett U-värde på 3W/m2K och tillsammans med plåttaket så bildar det ett undermåligt klimatskal utan möjligheter att skydda mot hettan. Det leder idag till endera ett obehagligt varmt inneklimat eller en hög och kostsam energianvändning av luftkonditionering. Överbelastningen på elnätet på grund av luftkonditionering är påtaglig under den varmaste säsongen med frekventa strömavbrott till följd. Denna rapport undersöker via laboratorieexperiment vilka termiska och mekaniska egenskaper man kan erhålla genom att vibrera lerjord och blanda med vatten, organiska fibrer samt kalk och/eller cement. Litteraturstudier och fältbesök i Burkina Faso har gjorts för att undersöka och förstå vilka svårigheter som kan uppkomma genom att bygga med lera. Rapporten tar även upp konkreta exempel på byggnader i Burkina Faso gjorda av lokala material, historiska såväl som moderna projekt. Lerjord behöver extremt lite energitillförsel för att bilda ett byggmaterial och den negativa miljöpåverkan är försumbar jämfört med betong och stål. Det kan användas för att bygga energisnåla hus men det är känsligt mot vatten, vilket måste beaktas noga under projekteringen. Värmeledningsförmågan är för hög för att vara tillräcklig som isolering för att erhålla ett inneklimat enligt dagens standard, utan tillförsel av energi, så någon form av extra isolering krävs. Experimenten som gjordes gav inte tillräckligt exakta resultat för att visa om vibrering är en bra metod att göra byggmaterial eller inte. Den höga vattenhalten som krävs för vibrering är ett stort problem. Krympningen var ungefär 20 % och sprickor var svåra att undvika. Vidare studier på området rekommenderas.
Novák, Petr. "Architektura pasivních domů na venkově." Doctoral thesis, Vysoké učení technické v Brně. Fakulta architektury, 2014. http://www.nusl.cz/ntk/nusl-233267.
Full textViero, Edison Humberto. "Aplicação de areia de britagem de rochas basálticas na fabricação de concreto de cimento Portland." reponame:Repositório Institucional da UCS, 2010. https://repositorio.ucs.br/handle/11338/571.
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Despite the technological advances on the structural concrete production, in natura materials are still used. This fact has been causing environmental and economic problems to the manufacturing chain. One of the problems is related to the sand extraction from riverbeds, this is the reason why professionals involved with concrete technology are searching for alternatives to the use of this type of sand in the structural concrete manufacturing. One alternative that is being studied in various parts of the country, because its large availability is a sand produced from the rocks´ comminution, called crushing sand. In the Caxias do Sul region there are large reservations of basaltic rocks origin (Riodacitos), from which it is possible to produce this type of sand. In this work, it was evaluated the feasibility of substitute natural sand for crushing sand from basaltic rocks produced in five mining companies located at Caxias do Sul region. The study was developed in three stages: on the first one, the features of the sand that arises from rocks´ mineralogy and petrography and from the mining manufacturing process were evaluated; on the second the concrete properties through the EPUSP/IPT dosage method were evaluated; on the third they were produced specific trace to each type of sand in order to verify the efficiency of the dosage method. The characterization results established that the crushing sand have different features IF compared with natural sand and that Just two out of Five evaluated sands presented properties that allow its use in structural concrete. The properties arising from the fabrication process, for example the presence of powder material, the grains´ shape and texture caused the raise of the plaster content, which influenced directly on the constituents materials proportioning. The results of the concrete properties evaluation showed that, for the same trace, the resistance to axial compression and the elasticity module are smaller in the concretes produced with crushing sand. If the plaster content is corrected and the specific traces are produced for each type of sand it is possible to produce concretes with desired resistance. In spite of the differences found on the sand properties it was proven that the crushing sand produced at the Caxias do Sul region can be used on the portland cement structural concrete production, replacing totally the natural sand used.
Gross, Steven James. "A Feasibility Study of Model-Based Natural Ventilation Control in a Midrise Student Dormitory Building." PDXScholar, 2011. http://pdxscholar.library.pdx.edu/open_access_etds/449.
Full textMADUAR, MARCELO F. "Determinacao de fatores de conversao de dose para radiacao gama externa em residencias." reponame:Repositório Institucional do IPEN, 2000. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10816.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
Lošáková, Jana. "Porovnání nákladů výstavby rodinného domu z klasických materiálů a z materiálů přírodních." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240414.
Full textFERREIRA, ADEMAR de O. "Avaliação da radioatividade natural em algumas rochas graníticas do Estado do Paraná e sua utilização na construção civil." reponame:Repositório Institucional do IPEN, 2013. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10204.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
VILLAVERDE, FREDDY L. "Avaliacao da exposicao externa em residencia contruida com fosfogesso." reponame:Repositório Institucional do IPEN, 2008. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11754.
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Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
Mašková, Pavla. "Posouzení ekonomické efektivnosti pasivního domu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240438.
Full textDelencre, Florent. "Terres et pierres pour matières de cultures : l'apparition et la diffusion de nouveaux modes et matériaux de construction dans le Nord-Est de la Gaule romaine (IIème siècle avant J.-C. - IIème siècle après J.-C.)." Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCH026/document.
Full textRoman building materials often arose a growing interest through their presence in early contexts, sometimes way before Gallic Wars. Made from natural resources, their final shape corresponds to anthropogenic and cultural constraints. However, even if building materials are not neglected during archaeological excavations, so far they have been considered as playing a minor part in understanding ancient sites. Economical, technical and architectural aspects are regularly mentioned, creating the picture of an exploited « landscape » around the studied areas, but the question of materials as cultural markers witnessing intercultural relations between Rome and Gallic tribes has never really been considered. The forensic listing of archaeological data for the North-Eastern Gaul highlights distinct rythms for the adoption of new construction habits, which are characterized by peculiar material arrangements echoing Roman administrative limits. Moreover, the diversity of the materials used is linked to the local presence or absence of the required resources for their production. On a wider scale, two groups can be defined by opposed terms : Gallic tribes only concerned by local natural resources for the production of building materials and those who transport them, sometimes over great distances. These elements allow us to discuss the issue about the double aspect of identities (civic and provincial) which can be the source of these discrepancies. In the same time, the geographical area concerned by our multi-scale analysis shows various administrative, social and cultural situations testifying of complex relations maintained with Rome and the Roman culture
Toll, D. G. "The behaviour of unsaturated compacted naturally occuring gravel." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/8006.
Full textČáslava, Petr. "Šetrné bydlení na venkově." Doctoral thesis, Vysoké učení technické v Brně. Fakulta architektury, 2013. http://www.nusl.cz/ntk/nusl-233251.
Full textLarsen, Matthew. "Material and Form." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/31336.
Full textMaster of Architecture
Pohanková, Lucie. "Architektura ekofarem v České republice." Doctoral thesis, Vysoké učení technické v Brně. Fakulta architektury, 2012. http://www.nusl.cz/ntk/nusl-233237.
Full textŠvec, Martin. "Revitalizace hotelového zařízení, Přehrada Brno." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2014. http://www.nusl.cz/ntk/nusl-216102.
Full textAydin, Gezer Nevin. "The Effects Of Construction Materials On Thermal Comfort In Residential Buildings." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/4/1104645/index.pdf.
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previous thermal experiences, the availability of control, and shifts in expectations. The study therefore focused on collecting data on both indoor and outdoor air temperature and humidity to show the comfort level in such buildings. By collecting data on 3 houses constructed of different materials the author aimed to show the effects of materials on thermal comfort. The analyses were further extended with computer simulations, which enabled restriction of the parameters on construction materials. The study has shown that in naturally ventilated residential buildings, construction materials affect both thermal comfort and thermal performance of the buildings. Buildings with traditional construction material showed a better performance in achieving the preferred thermal comfort while decreasing energy costs.
Eyer, David. "Vitalita v architektonickém prostředí." Doctoral thesis, Vysoké učení technické v Brně. Fakulta architektury, 2017. http://www.nusl.cz/ntk/nusl-263402.
Full textVacková, Michaela. "Stavba v krajině - Winery." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2009. http://www.nusl.cz/ntk/nusl-215607.
Full textAnder, Aleš. "ZOO DVŮR KRÁLOVÉ - VSTUPNÍ PAVILON." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2010. http://www.nusl.cz/ntk/nusl-215645.
Full textSvoboda, Petr. "Prezentační pavilon Papírny WANEMI, a.s. v Zábřehu." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2010. http://www.nusl.cz/ntk/nusl-215734.
Full textČábelková, Nahorniaková Marcela. "Organická soudobá architektura a bydlení." Doctoral thesis, Vysoké učení technické v Brně. Fakulta architektury, 2012. http://www.nusl.cz/ntk/nusl-233242.
Full textMiranda, Fuentes Johann. "Développement d'un modèle de Boltzmann sur gaz réseau pour l'étude du changement de phase en présence de convection naturelle et de rayonnement." Phd thesis, INSA de Lyon, 2013. http://tel.archives-ouvertes.fr/tel-00961213.
Full textHung, Kuo-Chen, and 洪國鈞. "The Measurement of Concentrations of Natural Radioactive Nuclides in Common Building Materials." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/03201380917357674060.
Full text國立清華大學
工程與系統科學系
89
Abstract This thesis investigates natural radioactivity of building materials in Taiwan with semi-empirical approach. Semi-empirical approach refers to detector measurement integrated with computer simulation. As computer simulation defines the detective efficiency of extensive sources no less accurate than detector measurement, this research uses computer simulation in combination with detector measurement to investigate natural radioactivity of building materials. For computer simulation, programs are developed based on Monte Carlo method. For detector, HPGe is chosen for its high resolution. Building materials sampled in this research include concrete, cement, glass, bricks and woods. Concrete, cement, and glass make up columns and walls in modern Taiwanese buildings, while bricks and woods consist of early Taiwanese houses. Few researches have been done on the radiation of these materials, due to their great variations in properties and sizes, which make it almost impossible to sample and test. The purpose of this thesis, despite the difficulties mentioned above, is to study the radioactivity of these common building materials, providing statistics for regulation institution and general public.
Adediran, Kehinde Mojisola. "Feasibility study on polyolefin reinforced natural fibre foam composites for structural applications." 2014. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001522.
Full textComposites of synthetic polymers and natural organic materials, used as fillers, find a wide application due to biodegradability, renewability, low-cost recyclability, low specific gravity, low weight, and non-abrasiveness to processing equipment. These composites find application in various areas such as automotive interior, households, ornaments, building, and packaging. In spite of these advantages, use of these materials as reinforcement or filler in thermoplastics in general and in polyolefin in particular, is not as extensive as expected. This is due to their limited thermal stability during processing, poor dispersion in the thermoplastic melt and limited compatibility with the matrix as well as poor toughness and stress transfer efficiency. The main objective of this research was to determine the suitability and performance of natural fibre reinforced polyolefin foam composite material as a possible construction material.
Fitzmaurice, Matthew Blake 1988. "Developing a Methodology for Characterizing the Effects of Building Materials’ Natural Radiation Background on a Radiation Portal Monitoring System." Thesis, 2012. http://hdl.handle.net/1969.1/148144.
Full textTattersall, Graham. "Structural Testing of Compressed Earth Blocks and Straw Bale Panels." Thesis, 2013. http://hdl.handle.net/1974/8442.
Full textThesis (Master, Civil Engineering) -- Queen's University, 2013-10-30 09:26:46.491
Lu, Chung-Hsin, and 盧仲信. "Concentration Measurement & Dose Assessment of Natural Radioactive Nuclides in Building Material." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/06574409711479714053.
Full textCarlos, Carlota Pereira de Almeida. "Advanced optical spectroscopy of new materials for luminescent solar concentrators." Master's thesis, 2019. http://hdl.handle.net/10773/29191.
Full textA transição da matriz energética atual para fontes de energia competitivas de baixo impacto ambiental é uma problemática central no século XXI. A arquitetura energeticamente sustentável é um ponto estratégico nesse esforço, através da realização dos chamados edifícios de energia zero. Por defenição, estes edifícios fazem uso de sistemas de produção de energia renovável local, como por exemplo a fotovoltaica, para satisfazer as suas necessidades energéticas. Assim, novas tecnologias que integrem dispositivos de coleção de energia solar em edifícios existentes ou recémconstruídos são de crescente relevância. Os concentradores solares luminescentes são dispositivos compostos por uma matriz transparente com centros óticos ativos incorporados. Estes absorbem a radiação incidente, que é posteriormente reemitida com um comprimento de onda específico e transportada por reflexão interna total até à célula fotovoltaica localizada nas extremidades da matriz. Esta configuração permite a produção de dispositivos fotovoltaicos incorporados em fachadas de edifícios e janelas, permitindo que estes sejam transformados em unidades de produção de energia. Atualmente, um dos desafios na áreas dos concentradores solares luminescentes é a incorporação de moléculas orgânicas naturais como centros óticos. Neste âmbito, foram fabricados e processados híbridos orgânico-inorgânicos semitransparentes, denominados por ureiasils, modificados por dois corantes orgânicos naturais, clorofila e proteína verde fluorescente (eGFP). A dinâmica entre os estados excitados dos corantes naturais e da matriz híbrida foi estudada e caracterizada - foram identifícadas as bandas de absorção da clorofila a e da eGFP, assim como a sua emissão característica no vermelho/infravermelho próximo (600-750 nm) e na região do visível (450-600 nm), respetivamente. As propriedades de emissão foram quantificadas através de medidas de rendimento quântico absoluto, registando-se um valor máximo para o híbrido com eGFP incorporada (0,33+/-0,03) duas vezes superior ao encontrado para as matrizes híbridas dopadas com clorofila (0,15+/-0,02). Foram também analisados os tempos de vida dos emissão dos estados excitados das várias amostras, tendo sido encontrados valores ~5 ns para a clorofila e ~2-3 ns para a eGFP, em solução ou quando incorporadas nas matrizes híbridas. Procedeu-se ainda a uma análise mais aprofundada no caso das amostras com eGFP, através da aplicação de um modelo bi-exponencial às curvas de decaimento, uma vez que o modelo eletrónico da mesma indica a presença de dois estados excitados distintos responsáveis pela absorção em torno dos 488 nm e emissão a 510 nm. Devido às características fotoluminescentes interessantes das amostras à base de corantes naturais para aplicações em concentradores solares luminescentes, foram fabricados e caracterizados dois protótipos com geometria planar { um concentrador solar luminescente baseado num recipiente de vidro cheio com eGFP em solução aquosa, e um outro concentrador que consistia num monolito da matriz híbrida dopada com eGFP. Os dispositivos foram acoplados a uma célula fotovoltaica comercial de silício, revelando eficiências óticas de conversão máximas de 2; 99+/-0; 01% e 3; 70+/-0; 06%, respetivamente, ilustrando o potencial desta abordagem para o desenvolvimento de sistemas energéticos sustentáveis e competitivos.
Mestrado em Engenharia Física