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Kietojo biokuro katilinės bandymų rėžiminis tyrimas / Regime Studies Test Of Solid Biofuel BoilerLazarenka, Vitas 21 June 2013 (has links)
Lietuvoje nėra didelių iškastinio kuro išteklių (akmens anglies, gamtinių dujų ar naftos), galinčių patenkinti šalies energetinius poreikius. Todėl Lietuvai yra ypač svarbus tinkamas vietinių ir atsinaujinančių energijos išteklių galimybių išnaudojimas. Didžiausią potencialą Lietuvoje turi biomasė ir biokuras. Taip pat ne mažiau reikšmingas bioenergijos gamybos ir naudojimo privalumas yra mažesnis neigiamas poveikis aplinkai bei klimatui. Magistrantūros baigiamojo darbo tikslas yra išanalizuoti Lietuvos medienos išteklius bei jų atsinaujinimą. Išanalizuoti biokuro katilinių parametrus esant skirtingam šiluminiam našumui ir sudaryti bandymų lentelę remiantis energetiniame objekte sumontuota pakura. Darbe atliekama kietojo biokuro sudėties ir charakteristikų analizė. Aprašomas technologinio proceso automatinis valdymas, katilinės sandara ir t.t. / Lithuania there are no significant fossil fuel resources (coal, natural gas or oil) that can meet the country's energy needs. Therefore, the country is vital to the local and renewable energy opportunities. Lithuania has the highest potential of biomass and biofuels. It is also no less important bioenergy production and use of the advantage of a lower negative impact on the environment and climate. Master's thesis is to analyze the Lithuanian wood resources and their regeneration. Also consider biofuel combustion process using the latest technology of biofuels through the regime of the test results table. The work carried out in the solid biofuel composition and characteristics of the analysis. Chosen object and the regime carried out research and calculations to determine the biomass boiler parameters at different thermal performance. Describe the process automatic control, boiler structure.
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Modeling of Biorefinery Supply Chain Economic Performance with Discrete Event SimulationAmundson, Joseph S 01 January 2013 (has links)
As competition for fossil fuels accelerates, alternative sources of chemicals, fuels, and energy production become more appealing to researchers and the layman. Among the candidates to fill this growing niche is lignocellulosic biomass. Many researchers have examined supply chain design and optimization for biofuel and bioenergy production throughout the years. However, these models often fail to capture the variability and uncertainty inherent to the biomass supply chain. Multiple factors with high degrees of stochasticity can have major impacts on the performance of a biorefinery: weather, biomass quality, feedstock availability, and market demand for products are just a few. To begin to address this issue, a discrete event simulation model has been developed to examine the economic performance of a region specific, multifeedstock biorefinery supply chain. Probability distributions developed for product demand and feedstock supply begin to address the random nature of the supply chain. Model development is discussed in the context of a multidisciplinary framework for biorefinery supply chain design. A case study, sensitivity analysis, and scenario analysis, are utilized to examine the capabilities of the model.
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Design and characterisation of the electrodes of enzymatic biofuel cells / Fermentiniams biokuro elementams skirtų elektrodų kūrimas ir charakterizavimasKrikštolaitytė, Vida 06 October 2014 (has links)
The objectives of the doctoral thesis are following: (i) to design carbohydrate/oxygen enzymatic biofuel cells (EBFCs); (ii) to determine the factors limiting the performance of EBFCs; (iii) to characterise the bioelectrochemical properties of the enzymes adsorbed at conductive nanostructures and evaluate the viscoelasticity of these nanostructures.
In this work 5-amino-1,10-phenanthroline (5AP) has been found to be the best redox mediator for glucose oxidase (GOx) enzyme among five studied phenanthroline derivatives with different functional groups. Later the 5AP cross-linked with GOx enzyme on a graphite rod electrode (GRE) was employed as an anode while GRE with co-immobilised horseradish peroxidase (HRP) and GOx was exploited as a cathode in order to design a glucose powered EBFC.
A positively charged bi-functional thiol, N-(6-mercapto)hexylpyridinium (MHP), was exploited to electrostatically attach the cellobiose dehydrogenase (CDH) enzymes from Corynascus thermophilus (CtCDH) and Humicola insolens (HiCDH) to the gold nanoparticle (AuNP) surface. This coupling enabled a sufficient direct electron transfer between the enzymes and the AuNP-modified gold surface. Therefore, the HiCDH enzyme, showing better performance characteristics, was employed as an anodic biocatalyst in the designing of a mediatorless carbohydrate (glucose or lactose)/oxygen EBFC. The biocathode of the EBFC was based on bilirubin oxidase from Myrothecium verrucaria directly immobilised on the surface... [to full text] / Disertacinio darbo tikslai: (i) sukonstruoti fermentinius angliavandenių/deguonies biokuro elementus (FBKE); (ii) nustatyti FBKE veikimą ribojančius faktorius; (iii) apibūdinti fermentų, adsorbuotų laidžiose nanostruktūrose, bioelektrokatalizines charakteristikas ir įvertinti šių nanostruktūrų viskoelastines savybes.
5-amino-1,10-fenantrolino (5AF) junginys, iš penkių šiame darbe tirtų fenantrolinų junginių besiskiriančių funkcinėmis grupėmis, įvertintas kaip geriausias elektronų pernašos (EP) tarpininkas gliukozės oksidazės (GO) katalizuojamoje heterogeninėje reakcijoje. 5AF junginys kartu su GO fermentu (5AF/GO) buvo panaudotas anodinio elektrodo konstrukcijoje, o atitinkamai bifermentinė krienų peroksidazės (KP) ir GO sistema (KP/GO) – katodinio elektrodo konstrukcijoje. Šie elektrodai panaudoti gliukozės FBKE kūrimui.
Teigiamą krūvį turintis bifunkcinis tiolinis N-(6-merkapto)heksilopiridinio (MHP) junginys panaudotas fermentų imobilizacijai aukso nanodalelių (AuND) paviršiuje elektrostatinės sąveikos būdu. AuND paviršiuje imobilizuoti celiobiozės dehidrogenazės (CDH) fermentai, išskirti iš Corynascus thermophilus (CtCDH) ir Humicola insolens (HiCDH) kamienų, sudarė fermentas-AuND sąsają įgalinančią tiesioginę EP. HiCDH fermentas kaip biokatalizatorius pritaikytas anodinio elektrodo konstrukcijoje AuND/MHP/HiCDH kuriant tiesiogine EP paremtus angliavandenių (gliukozės, laktozės)/deguonies FBKE. Bilirubino oksidazė (BO), tiesiogiai imobilizuota AuND paviršiuje (AuND/BO)... [toliau žr. visą tekstą]
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Fermentiniams biokuro elementams skirtų elektrodų kūrimas ir charakterizavimas / Design and characterisation of the electrodes of enzymatic biofuel cellsKrikštolaitytė, Vida 06 October 2014 (has links)
Disertacinio darbo tikslai: (i) sukonstruoti fermentinius angliavandenių/deguonies biokuro elementus (FBKE); (ii) nustatyti FBKE veikimą ribojančius veiksnius; (iii) apibūdinti fermentų, adsorbuotų laidžiose nanostruktūrose, bioelektrokatalizines charakteristikas ir įvertinti šių nanostruktūrų viskoelastines savybes.
5-amino-1,10-fenantrolino (5AF) junginys, iš penkių šiame darbe tirtų fenantrolinų junginių besiskiriančių funkcinėmis grupėmis, įvertintas kaip geriausias elektronų pernašos (EP) tarpininkas gliukozės oksidazės (GO) katalizuojamoje heterogeninėje reakcijoje. 5AF junginys kartu su GO fermentu (5AF/GO) buvo panaudotas anodinio elektrodo konstrukcijoje, o atitinkamai bifermentinė krienų peroksidazės (KP) ir GO sistema (KP/GO) – katodinio elektrodo konstrukcijoje. Šie elektrodai panaudoti gliukozės FBKE kūrimui.
Teigiamą krūvį turintis bifunkcinis tiolinis N-(6-merkapto)heksilopiridinio (MHP) junginys panaudotas fermentų imobilizacijai aukso nanodalelių (AuND) paviršiuje elektrostatinės sąveikos būdu. AuND paviršiuje imobilizuoti celiobiozės dehidrogenazės (CDH) fermentai, išskirti iš Corynascus thermophilus (CtCDH) ir Humicola insolens (HiCDH) kamienų, sudarė fermentas-AuND sąsają įgalinančią tiesioginę EP. HiCDH fermentas kaip biokatalizatorius pritaikytas anodinio elektrodo konstrukcijoje AuND/MHP/HiCDH kuriant tiesiogine EP paremtus angliavandenių (gliukozės, laktozės)/deguonies FBKE. Bilirubino oksidazė (BO, tiesiogiai imobilizuota AuND paviršiuje (AuND/BO)... [toliau žr. visą tekstą] / The objectives of the doctoral thesis are following: (i) to design carbohydrate/oxygen enzymatic biofuel cells (EBFCs); (ii) to determine the factors limiting the performance of EBFCs; (iii) to characterise the bioelectrochemical properties of the enzymes adsorbed at conductive nanostructures and evaluate the viscoelasticity of these nanostructures.
In this work 5-amino-1,10-phenanthroline (5AP) has been found to be the best redox mediator for glucose oxidase (GOx) enzyme among five studied phenanthroline derivatives with different functional groups. Later the 5AP cross-linked with GOx enzyme on a graphite rod electrode (GRE) was employed as an anode while GRE with co-immobilised horseradish peroxidase (HRP) and GOx was exploited as a cathode in order to design a glucose powered EBFC.
A positively charged bi-functional thiol, N-(6-mercapto)hexylpyridinium (MHP), was exploited to electrostatically attach the cellobiose dehydrogenase (CDH) enzymes from Corynascus thermophilus (CtCDH) and Humicola insolens (HiCDH) to the gold nanoparticle (AuNP) surface. This coupling enabled a sufficient direct electron transfer between the enzymes and the AuNP-modified gold surface. Therefore, the HiCDH enzyme, showing better performance characteristics, was employed as an anodic biocatalyst in the designing of a mediatorless carbohydrate (glucose or lactose)/oxygen EBFC. The biocathode of the EBFC was based on bilirubin oxidase from Myrothecium verrucaria directly immobilised on the surface... [to full text]
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Politics and Economics of Ethanol and Biodiesel Production and Consumption in BrazilGiersdorf, Jens 23 July 2014 (has links) (PDF)
Biofuel production has grown considerably between 2004 and 2009. Global ethanol production more than doubled from 30 to 76 billion litres (1,609 PJ1) while global biodiesel grew eight-fold from 2 to 17 billion litres (550 PJ2) (REN21 Secretariat 2010, 13). In 2008, biofuels provided 2,109 PJ of fuel consumption, while global oil and natural gas consumption for the transport sector amounted to 93,282 PJ (International Energy Agency 2010). Mandatory blending of biofuels has been enacted in at least 41 states/provinces and 24 countries at the national level in 2009, and the EU Directive 2009/28/EC mandates the member states to ensure that at least 10% of the final consumption of energy in transport shall come from renewable sources (European Parliament 2009). Although specific framework conditions and objectives of these programmes differ from country to country, the following overall driving forces can be identified since they represent global challenges (International Transport Forum of the Organisation for Economic Co-operation and Development 2008a, 4). [... aus der Einleitung]
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Frame Analysis in Environmental Conflicts : The case of ethanol production in BrazilGalli, Ester January 2011 (has links)
Governments and policy-makers are currently dealing with some key issues as energy security in countries dependent on oil imports; global economic development, including increased food production; and controlling global climate change and greenhouse gas emissions. The perception that biofuel could solve these challenges simultaneously has led to the implementation of policy and regulatory mechanisms on the mandatory use of biofuels, resulting in a sharp increase in biofuel production and consumption. Serious concerns about large-scale ethanol production have been raised regarding loss of biodiversity and competition for land between food and ethanol production. It is also suggested that sugarcane-based ethanol increases GHG emissions due to indirect land use change. Furthermore, sugarcane harvesting has been criticised for causing air pollution and bad working conditions for cutters. These criticisms have mostly been denied by Brazilian actors. This thesis seeks to clarify these divergent views and conflicts concerning Brazilian ethanol. It was carried out within a KTH research programme that uses frames in the analysis of conflicts emerging from the development and implementation of new technologies. Frame analysis can help improve understanding of such conflicts, which derive from differences in values, world views and beliefs and can be difficult to resolve. Frame analysis seeks to identify the particular factors determining the actions taken by different stakeholders, giving equal treatment to all actors. The results showed that the international views expressed in the media captured the attention of the public and policy-makers, and led them to frame ethanol as a destructive for nature fuel. The analysis identified that the ethanol as a threat to food security frame combined with the ethanol as a destructive for nature frame led the public and policy-makers to frame ethanol as a brown fuel. However, Brazilian actors frame ethanol differently: as a green and safe fuel. These differences have raised the conflicts that are analysed in this thesis. Furthermore, the analysis identified that the changes in the harvesting system, from manual to mechanised –besides decreasing air pollution- will cost the job of hundreds of thousands of cane cutters. Values and beliefs orientating such changes are analysed in the thesis. / QC 20110912
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DESEMPENHO EM DINAMÔMETRO E EMISSÕES RESIDUAIS DE UM MOTOR DE TRATOR AGRÍCOLA OPERANDO COM MISTURAS BINÁRIAS DE ÓLEO DIESEL B5 E BIODIESEL DE ÓLEO DE FRANGO / PERFORMANCE IN DYNAMOMETER AND EMISSIONS OF WASTE AN AGRICULTURAL TRACTOR ENGINES OPERATING WITH BINARY MIXTURES B5 DIESEL AND BIODIESEL OIL CHICKENFiorese, Diego Augusto 28 February 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Brazil, the third largest producer of biodiesel in the world, and also the third largest producer of chicken, may increase in some regions, the use of oil derived from birds, as an alternative to fossil fuels. In order to increase the range of options to reduce dependence on soybean oil for that purpose, and fostering environmental aspects, it is possible to produce biodiesel from chicken oil, the country that can provide more than 300 thousand tons of oil per year. Considering the application of alternative fuels for diesel engines, agricultural machinery, the study aimed to evaluate the performance of a tractor of 53 kW in a dynamometer bench, and the level of emissions of certain waste gases of combustion, operating with biodiesel methyl chicken oil and various binary mixtures with diesel B5. We evaluated the values of torque and power produced, fuel consumption, power consumption and thermal efficiency of the engine, as well as the levels of gases (carbon dioxide, CO2, carbon monoxide, CO, unburned hydrocarbons, HC; and oxygen, O2). We used six blends of diesel with biodiesel B5 (control), B20, B40, B60, B80 and B100. The trial was conducted with a randomized design (CRD) in a factorial design, which was held after the analysis of variance and the average adjusted for regression equations. Integrating the data, the most significant results showed advantages for the B20. Minor losses were observed in the generation of power and torque, increase in specific fuel consumption, improved engine thermal efficiency and reduced energy consumption by increasing the proportion of biodiesel in the blend. The best emission results showed a reduction in emissions of CO, in the order of 80% when operating with B100. The CO2 reduction was not significant and the level of unburned HC was higher than the control blends B60, B80 and B100. / O Brasil, terceiro maior produtor de biodiesel do mundo, e também terceiro maior produtor mundial de frango, pode incrementar em algumas regiões do país, o uso de óleo oriundo de aves, como alternativa aos combustíveis fósseis. Com vistas ao aumento do leque de opções, a redução da dependência do óleo de soja para tal fim, e fomentando aspectos ambientais, é possível produzir biodiesel de óleo de frango, que no país, pode disponibilizar mais de 300 mil toneladas de óleo por ano. Considerando a aplicação dos combustíveis alternativos para os motores diesel, em máquinas agrícolas, o trabalho teve por objetivo avaliar o desempenho de um trator agrícola de 53 kW em bancada dinamométrica, e o nível de emissões de alguns gases residuais de combustão, operando com biodiesel metílico de óleo de frango e diversas misturas binárias com óleo diesel B5. Avaliou-se os valores de potência e torque produzidos, consumo de combustível, consumo de energia e a eficiência térmica do motor, bem como os teores de gases produzidos (dióxido de carbono, CO2; monóxido de carbono, CO; hidrocarbonetos não queimados, HC; e oxigênio, O2). Utilizaram-se seis misturas de óleo diesel com biodiesel: B5 (testemunha), B20, B40, B60, B80 e B100. O ensaio foi instalado com delineamento inteiramente casualizado (DIC) em esquema fatorial, sendo que após foi realizada a análise de variância e as médias ajustadas por equações de regressão. Integrando-se os dados, os resultados mais expressivos mostraram vantagens para o B20. Foram observadas perdas pouco significativas na geração de potência e torque, aumento no consumo específico, melhoria na eficiência térmica do motor, e redução do consumo energético com o aumento da proporção de biodiesel na mistura. Os melhores resultados das emissões mostraram uma redução nas emissões de CO, na ordem de 80%, quando operando com B100. O CO2 teve redução pouco expressiva e o nível de HC não queimados foi superior ao da testemunha nas misturas B60, B80 e B100.
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DESEMPENHO E EMISSÕES DE UM MOTOR DE TRATOR AGRÍCOLA OPERANDO COM MISTURAS DE ÓLEO DIESEL E ETANOL / PERFORMANCE AND EMISSIONS OF A FARM TRACTOR ENGINE OPERATING WITH BLENDS OF DIESEL AND ETHANOLEstrada, Javier Solis 05 March 2015 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The growing demand of energy in the world, the decrease of petroleum reserves and
the current problems of environmental contamination, increase the interest in
renewable energy study for internal combustion engines, to replace partially or
completely to petroleum based fuels. In Brazil, among the alternatives fuels, stands
out the use of sugarcane ethanol, seen that it is from renewable sources and has
high oxygen content, which is favorable to reduce pollutant gases emissions of
engine. The blend of ethanol and diesel (ED) has received in recent years and in
different countries, more attention for use in diesel engines. However, there are
difficulties to partially replace diesel use. The main disadvantages are the differences
in their physical-chemical properties. A percentage up to 15% of ethanol is used in
diesel engines without making mechanical changes. In this way, the objective of this
study was to evaluate the performance and emissions of a diesel engine in an
agricultural tractor, using blends of diesel and hydrated ethanol. Were used as fuel,
Diesel (B5) and mixture with 3% (ED3), 6% (ED6), 9% (ED9), 12% (ED12) and 15%
(ED15) of hydrous ethanol. Performance parameters evaluated were the power,
torque and specific fuel consumption. Were also evaluated emissions of CO2, NOx e
O2, and the opacity of the gases through the k value. Both, engine performance and
emissions experiment were analyzed in a completely randomized with bifactorial
design. The results indicate that as the percentage of ethanol increased, the average
values of torque and engine power decreased. Using the B5 and the ED3, these
variables did not differ statistically, in addition, with the ED3 was obtained the lower
specific fuel consumption. Using ED12, the engine performance has reduced power
and torque in 2.97% e 2.95%, respectively, compared with B5, while their fuel
consumption had no statistical difference. The greater opacity and gas emissions
were archive with ED3, while the lower emission occurred when the engine operated
with ED12 and ED15. With these fuels, the reduction of opacity, CO2 and NOX, in
relation to B5, was 22.22 24.44%, 5.20 5.60% e 6.65 - 10.48%, respectively. It
can be considerate that operating with ED12, pollutant emissions are reduced
significantly without a significant loss in engine performance. / A crescente demanda mundial de energia, a diminuição das reservas do petróleo e
os atuais problemas de poluição ambiental, incrementam o interesse no estudo de
fontes renováveis de energia para os motores de combustão interna, visando
substituir, de forma parcial ou total, os combustíveis derivados do petróleo. No Brasil,
entre os combustíveis alternativos, se destaca o uso do etanol de cana-de-açúcar,
visto que é de origem renovável e possui um alto conteúdo de oxigênio, o qual pode
favorecer a redução das emissões de gases poluentes do motor. A mistura etanol-
Diesel (ED) vem recebendo, nos últimos anos, e em diferentes países, maior
atenção para ser utilizado em motores ciclo Diesel. No entanto, existem dificuldades
para sua utilização visando substituir parcialmente o óleo Diesel. Os principais
inconvenientes são as diferenças nas suas propriedades físico-químicas. Em
porcentagens de até 15%, o etanol pode ser utilizado em motores ciclo Diesel, sem
realizar modificações mecânicas. Desta forma, o objetivo deste trabalho foi avaliar o
desempenho e as emissões de um motor ciclo Diesel de um trator agrícola,
utilizando misturas de óleo Diesel e etanol hidratado. Foram utilizados como
combustíveis o óleo Diesel (B5) e sua mistura com 3% (ED3), 6% (ED6), 9% (ED9),
12% (ED12) e 15% (ED15) de etanol. Os parâmetros avaliados de desempenho
foram: a potência, o torque e consumo específico de combustível. Foram também
avaliadas as emissões de CO2, NOx, O2 e a opacidade dos gases, por meio do valor
k. Ambos os experimentos de desempenho e emissões do motor foram analisados
em um delineamento experimental inteiramente casualizado, em um esquema bi
fatorial. Os resultados indicam que conforme aumentou a porcentagem de etanol, os
valores médios de torque e potência do motor diminuíram. Utilizando o B5 e o ED3,
estas variáveis não diferiram estatisticamente, além disso, com o ED3 foi obtido o
menor consumo de combustível. Utilizando o ED12 o desempenho do motor teve
reduções de potência e torque de 2,97% e 2,95%, respectivamente, em relação ao
B5, enquanto que os consumos de combustível não tiveram diferença estatística. A
maior opacidade e emissões de gases foram alcançadas com ED3, enquanto que as
menores emissões ocorreram quando o motor operou com o ED12 e ED15. Com
estes combustíveis, a redução da opacidade, CO2 e NOx, em relação ao B5 foi de
22,22 - 24,44%, 5,20 - 5,60% e 6,65 - 10,48%, respectivamente. Pode-se considerar
que operando com o ED12, as emissões de poluentes são reduzidas
significativamente sem uma perda considerável no desempenho do motor.
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Dimensionering av pelletspanna : Ångkartläggning och dimensionering av en ny pelletspanna hos Fresenius Kabi i KungsängenForsström Skeppar, Joacim January 2018 (has links)
The current boilers at the Brunna plant were installed in 1979 using oil and solvents to produce steam for the production and heating of the plant. To reduce the carbon dioxide emissions in compliance with Fresenius Kabi strategy a new biofuel boiler is about to be installed. Since the steam demand has been reduced during the years and it’s expensive to install a new boiler this study has been performed to calculate the actual steam demand for the plant at different scenarios. A smaller boiler requires a lower investment, achieves higher efficency and contributes to reduced carbon dioxide emissions. This report is intended to supply the management with information so that a decision regarding investments and employees can be made. The result is presented as different possible scenarios that are of great importance when deciding which boiler effect that is needed. Destillation, heating and the production have a major impact and must be considered when installing a new boiler. The results show that a boiler should be between 2-4 MW net effect depending on which scenario that is most likely to occur.
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Conception guidée par la physiologie de biopiles bioinspirées implantables / Physiological considerations for the design and integration of bioinspired implantable biofuel cellsAlcaraz, Jean-Pierre 19 October 2016 (has links)
On peut imaginer dans un futur proche que des micro-robots implantés pourront suppléer la défaillance de certaines fonctions essentielles. C’est déjà le cas avec les stimulateurs cardiaques dont les piles au lithium sont bien adaptées à leur fonctionnement pendant des années de vie du patient. Cependant, pour des systèmes plus gourmands en énergie, il convient d’améliorer la longévité et la puissance volumique de ces piles. La stratégie que nous avons choisie est basée sur une approche biomimétique et deux voies ont été suivies pour créer une biopile bioinspirée : les biopiles enzymatiques génèrent un courant électrique à partir de l’oxydation de molécules organiques et la réduction d’oxygène en eau. Les biopiles à base de membranes biomimétiques génèrent un potentiel électrique à partir du transfert d’ions au travers une membrane biomimétique.Les biopiles enzymatiques, qui utilisent par exemple le glucose et l’oxygène, sont théoriquement capables de fonctionner indéfiniment car ces substrats sont toujours présents dans l’organisme. Cependant, la biocompatibilité et la performance à long terme de ces biopiles restent des verrous pour leur mise en œuvre chez l’homme. Cette thèse décrit la conception et l’implantation de nouvelles biopiles enzymatiques chez différents modèles animaux. Leur implantation constitue un véritable défi technologique et nous amenons des solutions guidées par la physiologie en abordant les problèmes de biocompatibilité mais aussi de techniques de mesure électrique.Nous sommes maintenant capables d’implanter ces biopiles chez de gros animaux en analysant en temps réel les performances de la biopile implantée.Cette thèse développe également le concept de biopile à base de membranes biomimétiques. Il s’agit d’une biopile mettant en œuvre des protéines de transport (par exemple des canaux ioniques) insérées dans des membranes biomimétiques. Nous avons démontré la faisabilité de la transformation d’un gradient de NaCl en gradient de protons. Nous avons aussi réussi à générer une différence de potentiel de 20 millivolts avec une membrane plane de 38 mm². Cette membrane biomimétique, contenant l’échangeur sodium/proton NhaA, est stable pendant plus de 15 jours. / We believe that in the near future micro-robots or artificial implanted organs can replace failing essential organs. Lithium batteries of cardiac pacemakers are well adapted to operate for years into sick patients. However, for next generation energy intensive implanted devices, longevity and volumic power of these batteries have to be improved.We chose two biomimetic approaches to create bioinspired biofuel cells: the enzymatic biofuel cells generate electrical current from the oxidation and the reduction of organic or inorganic compounds. The biomimetic biofuel cell generate an electrical potential from ion transfer across a biomimetic membrane.The enzymatic biofuel.cells, utilizing glucose and oxygen, are theorically able to work almost indefinitely as their substrates are always present in the body fluids. However, the biocompatibility and the long-term performance of these biofuel cells for a human implantation remain a real bottleneck. This thesis describes the design and the implantation of of new enzymatic biofuel cells in different animal models. The implantation of such devices is challenging and we brought creative solutions with a physiological point of view by addressing biocompatibility problems and electrical measurement techniques. We are now capable to implant these biofuel cells in big animals by analyzing the performances of the biofuel cell in real time.This thesis initiates the biomimetic biofuel cell concept. It consists in membrane transport protein (i.e ion channels) incorporated in a biomimetic membrane. The building of a biomimetic device demonstrates the transformation of a NaCl gradient into a proton gradient. We also generate a 20 mV voltage with a 38 mm² flat membrane. This biomimetic membrane containing the NhaA sodium/ proton exchanger is stable for more than two weeks.
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