3122043 documents found, page 46100 of 312205

Oportunidades e desafios para as bioenergias : acordos de cooperação internacio...

Cerca de 80% da energia primária mundial provém da queima de combustíveis fósseis, com implicações a nível de emissões de gases que provocam o efeito de estufa, levando a opções de substituição com diversificação energética. A Bioenergia é uma das mais significativas contribuições no domínio das energias renováveis, sendo o recurso biomassa caracterizado pela sua versatilidade, e quando produzida e usada de for...

From expatriates’ information needs to information management in the expatriati...

Globalization has intensified the flow of companies’ top executives across borders. New information needs arise and are added to several other challenges faced by these executives when they move to a foreign country. Cultural differences of the host countries, and lack of local language skills preventing expatriates making sense of the social context and physical environment surrounding them, are among those ch...

Acciones para el desarrollo de las energias renovables

O parque experimental de energias renováveis da Herdade da Mitra, em Évora integra um sistema de microgeração de abastecimento eléctrico em Portugal, através da integração de diferentes unidades utilizadoras de fontes renováveis: fotovoltaica, eólica, gasificação e digestão anaeróbica. Neste capítulo serão abordadas estas diversas tenologias referindo os princípais conceitos teóricos que suportam cada uma delas...

Structured metal-zeolite catalysts for the catalytic combustion of VOCs

Corrosion inhibition of aluminium alloys by layered double hydroxides: the role...

Layered double hydroxides represented by the general formula [M2 2+M3+(OH)6]+X1/n n-.zH2O are being researched as anion-exchange materials with interesting intercalation chemistry that accommodate a wide range of applications, including corrosion resistance. In this work, it is shown that the formation of layered double hydroxides (LDHs) on the surface of copper-rich Al alloys promotes corrosion resistance. For...

Can small additions of an organic polymer or surfactant to sodium borohydride s...

Electrochemical energy conversion in direct methanol fuel cells: the effects of...

Water transport in PEM fuel cells

Electrodeposition of black chromium thin films from trivalent chromium-ionic li...

In the present study, black chromium thin films were electrodeposited from a solution of 1-butyl-3- methylimidazolium tetrafluoroborate ([BMIm][BF4] ionic liquid containing trivalent chromium (Cr(III)). Homogeneous and well adherent coatings have been obtained on nickel, copper and stainless steel substrates. The nucleation and growth of the films were investigated by cyclic voltammetry and current-density/time...

On the use of supercapacitors within stand-alone energy systems

Hydrogen is a valuable alternative for long-term energy storage, particularly for renewable energy based stand-alone systems. The described stand-alone system has been developed and installed at the INETI facilities. The exceeding renewable energy (provided by sun and wind) is used to generate hydrogen, which accumulated as an energy buffer, while the fuel cell uses this stored hydrogen to produce electrical en...