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Scenedesmus obliquus as feedstock for biohydrogen production by Enterobacter ae...

Hydrogen (H2) gas is seen as an ideal future energy carrier because it is easily converted into electricity in fuel cells, liberates a large amount of energy per unit mass, and generates no air pollutants. In this work, biological hydrogen (bioH2) was produced from the microalgal biomass of Scenedesmus obliquus which was used as a substrate for the fermentation by Enterobacter aerogenes ATCC 13048 and Clostridi...

A biorefinery from Nannochloropsis sp. microalga – Extraction of oils and pigme...

The microalga Nannochloropsis sp. was used in this study, in a biorefinery context, as biomass feedstock for the production of fatty acids for biodiesel, biohydrogen and high added-value compounds. The microalgal biomass, which has a high lipid and pigment content (mainly carotenoids), was submitted to supercritical CO2 extraction. The temperature, pressure and solvent flow-rate were evaluated to check their ef...

A biorefinery from Nannochloropsis sp. microalga – Energy and CO2 emission and ...

Are microalgae a potential energy source for biofuel production? This paper presents the laboratory results from a Nannochloropsis sp. microalga biorefinery for the production of oil, high-value pigments, and biohydrogen (bioH2). The energy consumption and CO2 emissions involved in the whole process (microalgae cultivation, harvest, dewater, mill, extraction and leftover biomass fermentation) were evaluated. An...

O desenvolvimento da literacia emergente na educação pré-escolar : representaçõ...

Dissertação de Mestrado em Supervisão Pedagógica (Infância e/ou Ensino Básico - 1º Ciclo). ; O presente estudo pretendeu analisar as representações de futuros educadores sobre a literacia emergente na educação pré-escolar, discutindo a relevância do desenvolvimento de estratégias formativas de natureza reflexiva para a consciencialização sobre as práticas utilizadas e sua eventual transformação. Com este estud...

Biological hydrogen production by Anabaena sp. – Yield, energy and CO2 analysis...

This paper presents laboratory results of biological production of hydrogen by photoautrotophic cyanobacterium Anabaena sp. Additional hydrogen production from residual Cyanobacteria fermentation was achieved by Enterobacter aerogenes bacteria. The authors evaluated the yield of H2 production, the energy consumption and CO2 emissions and the technological bottlenecks and possible improvements of the whole energ...

Biohydrogen fermantative production : energetic valorization of microalgae biomass

Renewable, sustainable and carbon-neutral energy production is needed to deal with the challenges of growing energy demand and climate change. Hydrogen (H2) is most promising in the succession of fuel evolution, with several technical, socio-economic and environmental benefits to its credit [1]. It is an excellent energy carrier as it has the highest energy content per unit weight/mass of any known fuel (142 kJ...

Microalgae as a sustainable raw material for biofuels production and high added...

Exploring Scenedesmus obliquus and nannochloropsis sp. potential as a sustianab...

In this work, the authors propose a microalga-based integrated system, where optimization of several energy vectors (biodiesel, bioethanol and bioH2) is highlighted under the concept of biorefinery (Project PTDC/AAC-AMB/100354/2008). This involves the integration of different processes such as oil and sugar extraction from microalgae for biodiesel and bioethanol production respectively, and bioH2 production fro...

Responsabilidade social das empresas e os consumidores : a articulação necessária

Mestrado em Marketing ; A Responsabilidade Social Empresarial (RSE) veio para ficar e consolida-se como atividade core para o equilíbrio económico de longo prazo, numa era em que os negócios e a sociedade caminham juntos. No entanto, algumas empresas ainda não concretizam a RSE de modo produtivo, pois necessitam definir os pontos de interceção com o seu negócio e compreender a articulação necessária na sua rel...

O aluno na relação escola/família : perspectivas de directores de turmas do 3º ...

Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Ciências da Educação ; O presente trabalho de investigação incide sobre o papel do aluno na relação escola/família e sobre o seu poder nesta relação. Ainda que a escola e a família sejam as detentoras de poder institucional na relação que estabelecem entre si, também o aluno possui poder nesta relação, que deriv...