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Browsing by Issue Date, starting with "2022-06-30"

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  • Benzimidazole Schiff base copper(II) complexes as catalysts for environmental and energy applications: VOC oxidation, oxygen reduction and water splitting reactions
    Publication . Paul, Anup; Silva, Tiago A. R.; Soliman, Mohamed M. A.; Karacic, Jozo; Sljukic, Biljana; Alegria, Elisabete; Khan, Rais Ahmad; Guedes Da Silva, M. Fátima C.; Pombeiro, Armando
    The new copper(II) complexes [Cu(mu-1 kappa O:2 kappa ONN'-HL1)(mu-1 kappa O:2 kappa O'-NO3)](2)center dot[Cu(mu-1 kappa O:2 kappa ONN'-HL1)(CH3OH)](2)(NO3)(2) (1) and [Cu(kappa ONN'-HL2)(mu-1 kappa OO':2 kappa O'-NO3)](n) (2), derived from the new pro-ligands H(2)L1 = 2-(5,6-dihydroindolo[1,2-c]quinazolin-6-yl)-5-methylphenol and H(2)L2 = 2-(5,6-dihydroindolo[1,2-c]quinazolin-6-yl)-4-nitrophenol, were synthesized and characterized by elemental analysis, FT-IR, ESI-MS, and their structural features were unveiled by single-crystal X-ray diffraction analysis. This discloses a dimeric structure for 1 and a polymeric infinite 1D metal-organic chain for 2. The complexes were evaluated as catalysts for the oxidation of toluene, a volatile organic compound (VOC), and for oxygen reduction and water splitting reactions. 1 exhibits a higher activity for the peroxidative conversion of toluene to oxygenated products (total yields up to 38%), whereas 2 demonstrates a superior performance for electrochemical energy conversion applications, i.e., for oxygen reduction (ORR), oxygen evolution (OER) and hydrogen evolution (HER) reactions in an alkaline medium in terms of higher ORR current densities, lower Tafel slope (73 mV dec(-1)) and higher number of electrons exchanged (3.9), comparable to that of commercial Pt/C. Complex 2 also shows a better performance with lower onset potential and higher current densities for both OER and HER when studied as electrocatalyst for water splitting.
    2022-06-30Journal article Restricted access Show more
  • The role of social media in the proliferation and promotion of Brand Activism
    Publication . Miguel, Alexandra; Miranda, Sandra
    Despite the relevance and actuality of brand activism, there are few theoretical investigations about the origins of this concept, and particularly about the role that social networks played in its proliferation and encouragement. This systematic literature review, based on the most prominent articles published in this field of expertise, investigates and discusses the role of technological advances, and particularly the role of the popularization of the use of social networks, in the proliferation of brand activism worldwide. Likewise, the concept of brand activism as a new trend in strategic communication between brands and stakeholders is explored, giving real examples of brand activism campaigns to present a current picture of the application of this concept, both online and offline.
    2022-06-30Journal article Open access Show more
  • Publicidade: novos formatos, novos conteúdos
    Publication . Verissimo, Jorge; Balonas, S.
    Este artigo apresenta-nos, por um lado, as intenções dos editores com este número temático, por outro, uma introdução aos textos aqui publicados. No que concerne ao primeiro intento, os editores pretendem, acima de tudo, estimular o debate em torno da publicidade, refletindo sobre a sua capacidade de adaptação aos desafios societais e tecnológicos, sem esquecer as tendências que o discurso publicitário anuncia ou incorpora. Quanto ao segundo, os editores do dossier “Publicidade: novos formatos, novos conteúdos” apresentam os vários contributos de investigadores que procuram espelhar a contemporaneidade através da publicidade, revelando que esta se continua a afirmar enquanto discurso e enquanto técnica no ecossistema comunicacional.
    2022-06-30Journal article Open access Show more