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Electrical properties and strain gauge factor of Cr/SiOx cermet films with compositions 50/50 and 70/30 wt% were investigated in order to evaluate their use in strain gauge devices. The films were deposited by flash evaporation. The microstructures and resulting phases were characterized by electron diffraction and electron microscopy. The influence of the thickness and deposition rate on the sheet resistance, the temperature coefficient of resistance and the gauge factor were investigated. The results are consistent with a mixed conduction mechanism with metallic and a thermally activated tunneling components, between interconnected and discrete conductive phases, respectively.Se investigaron las propiedades eléctricas y el factor extensométrico de pelÃculas del cermet- Cr/SiOx en composiciones 50/50 y 70/30 % en peso, para evaluar su uso en dispositivos "strain gauge". Las pelÃculas fueron depositadas por evaporación "flash". Las estructuras y fases resultantes fueron caracterizadas por microscopÃa y difracción de electrones. Se estudió la influencia del espesor y la velocidad del depósito sobre la resistencia laminar, el coeficiente térmico de resistencia y el factor extensométrico. Los resultados son consistentes con un mecanismo de conducción mixto, con una componente metálica y otra por efecto túnel térmicamente activado, entre fases conductoras interconectadas y discretas, respectivamente
A sustainable revolution: Let's go sustainable to get our globe cleaner
The concept of sustainability is a clear blue sea, a snowy mountain, a flowery meadow, in which there is resource sharing that allows us to satisfy human needs without damaging natural resources. The challenge is complex, and we hope to support the decarbonization of our society and mitigate climate changes. This Special Issue aims to outline different approaches in several sectors with a common point of view: seeing our world with a green perception and encouraging a sustainable revolution to provide a cleaner world
Demonstration of PLOTs from the EuroPLOT project
The EuroPLOT project (2010-2013) has been funded to explore the concept of persuasive design for learning and teaching. It has developed Persuasive Learn-ing Objects and Technologies (PLOTs), manifested in two tools and a set of learning objects that have been tested and evaluated in four different case studies. These PLOTs will be shown in this demonstration, and the participants can try them out and experience for themselves the impact of persuasive technology that is embedded in these PLOTs. This will be one authoring tool (PLOTMaker) and one delivery tool (PLOTLearner). Furthermore, there will be learning objects shown which have been developed for those four different case studies. All of these PLOTs have already been tested and evaluated during case studies with real learners
RKKY and magnetic field interactions in coupled Kondo quantum dots
We investigate theoretically the transport properties of two independent
artificial Kondo impurities. They are coupled together via a tunable
Ruderman-Kittel-Kasuya-Yoshida (RKKY) interaction. For strong enough
antiferromagnetic RKKY interaction, the impurity density of states increases
with the applied in-plane magnetic field. This effect can be used to
distinguish between antiferromagnetic and ferromagnetic RKKY interactions.
These results may be relevant to explain some features of recent experiments by
Craig et al. (cond-mat/0404213).Comment: 4 pages, 3 figure
Circular solar: Evaluating the profitability of a photovoltaic panel recycling plant
Photovoltaic (PV) panels have a crucial role in coping with the global warming mitigation and the energetic crisis currently affecting the European Community. However, from the circular perspective of end-of-life (EoL) management, there are still big issues to be solved in order to recover materials from this kind of e-wastes. Because of several reasons (e.g. type of embedded materials, illegal shipments, location of manufacturers) EoL businesses do not have the interest in approaching them. This poses a significant environmental concern in terms of their management. This work wants to assess the profitability of a specific PV module recycling plant, by evaluating several market contexts in which multiple scenarios of material price, investment and process costs will be considered. The results for a 3000 tonnes plant show that profitability is not verified in the absence of an avoided landfill cost. Instead, when a value of 200 euro/tonnes is applied, the net present value is positive in 35.2% of the scenarios and at 87.6% when a value of 350 euro/tonnes is considered. The policy choice of this value requires linking the PV module disposal fee to the circular benefits associated with its recovery
A comparison of environmental and energetic performance of European countries: A sustainability index
Recently, European countries agreed on a new 2030-pact establishing challenging levels for a set of climate and energy indexes in order to achieve a more competitive, safe and sustainable energy system. In order to evaluate current sustainability performances of European countries from the environmental and energetic perspectives, this research proposes a Multi-Criteria Decision Analysis (MCDA) that, starting from both Eurostat data and the Analytic Hierarchy Process (AHP), allows a direct comparison of nations. To this aim, multiple indexes are taken into account (e.g. Greenhouse gas (GHG) emissions, Government expenditures for environmental protection, Recycled and reused waste from electric and electronic equipments (WEEEs), Recycled and reused waste from end-of-life vehicles (ELVs), Recycled materials from Municipal Solid Wastes (MSWs), Share of renewable energy (RE) in electricity, Share of RE in transport, Share of RE in heating and cooling and Primary energy consumption). This assessment model provides a sustainability value for each European country and the related ranking with the European average. Results show as, even nowadays, twelve out of twenty-eight European countries have a value greater than the European average in 2013. Top four nations (Sweden, Denmark, Finland and Austria) have high indexes of sustainability and Sweden is the best country from both the environmental and energetic perspectives
Curva de voo e hospedeiros alternativos da praga Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) na cultura da framboesa na região do Algarve
Nos últimos anos muito se tem falado da produção dos pequenos frutos em
Portugal, nomeadamente da framboesa, sobretudo pelas condições edafoclimáticas
para a sua produção e de como se pode produzir frutos de sabor, cor e
aroma inigualáveis.
A chegada da Drosophila suzukii a Portugal em 2012 (EPPO, European and
Mediterranean Plant Protection Organization, 2012), veio provocar um grande
impacto económico na cultura dos pequenos frutos. Com a necessidade de
combater esta praga através de meios de luta amigos do homem, do ambiente e dos
seres vivos, os agricultores caminharam no sentido da proteção integrada. Em
proteção integrada é importante avaliar a possibilidade de utilizar armadilhas
alimentares para a estimativa do risco e monitorização das populações da praga.
Neste trabalho foi proposto estudar as curvas de voo desta praga na cultura da
framboesa na região do Algarve, relacionando a sua atividade com as condições
climáticas que a região apresenta. Foram estudadas três explorações agrÃcolas
produtoras de framboesa, que também apresentassem no seu perÃmetro possÃveis
hospedeiros alternativos para monitorizar.
Para a concretização deste estudo foram colocadas quatro armadilhas/ha na cultura
da framboesa e duas armadilhas em cada hospedeiro alternativo. Utilizou-se dois
atrativos alimentares diferentes, mas com o mesmo tipo de armadilha. A
monitorização das armadilhas realizou-se uma vez por semana, tal como a
renovação dos atrativos alimentares. Este estudo decorreu entre o mês de junho de
2015 e o mês de maio de 2016.
Na cultura da framboesa a maioria das capturas foi obtida após a entrada em
maturação dos frutos. Nos hospedeiros estudados, a alfarrobeira, o mato e a figueira
foram os que mais capturas apresentaram. No medronheiro comprovou-se que de
facto a praga usa esta planta para se reproduzir. Em todos os hospedeiros verificouse
maior captura de fêmeas do que machos. O atrativo levedura fresca + açúcar
com a armadilha convencional (garrafa de plástico de 1,5L) foi o que apresentou
maior eficácia nas capturas de D. suzukii.info:eu-repo/semantics/publishedVersio
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