Browsing by Issue Date, starting with "2022-03-15"
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- Carbon dots from coffee grounds: synthesis, characterization, and detection of noxious nitroanilinesPublication . Costa, Alexandra I.; Barata, Patrícia; Moraes, Bianca; Prata, José V.Coffee ground (CG) waste is generated in huge amounts all over the world, constituting a serious environmental issue owing to its low biodegradability. Therefore, processes that simultaneously aim for its valorization while reducing its environmental impact are in great demand. In the current approach, blue luminescent carbon dots (C-dots) were produced in good chemical yields from CGs following hydrothermal carbonization methods under an extended set of reaction parameters. The remarkable fluorescent properties of the synthesized C-dots (quantum yields up to 0.18) allied to their excellent water dispersibility and photostability prompted their use for the first time as sensing elements for detection of noxious nitroanilines (NAs) in aqueous media. Very high levels of NA detection were achieved (e.g., limit of detection of 68 ppb for p-nitroaniline), being the regioisomeric selectivity attributed to its higher hyperpolarizability and dipole moment. Through ground-state and time-resolved fluorescence assays, a static fluorescence quenching mechanism was established. H-1 NMR titration data also strongly suggested the formation of ground-state complexes between C-dots and NAs.
- The impact of social media communication on personal brand managementPublication . Machado, Evelin; Miranda, SandraIn contemporary societies, forms of communication have become, in many ways, predominantly online. The rise of social media has reshaped the culture of communication and created new virtual environments offering multiple opportunities for individuals to create profiles on different platforms, to communicate both personally and professionally. Although there is research on the phenomenon of Branding in social media, it is observed that the people-related perspective presents gaps in conceptual alignment and scientific depth and therefore holds immense room for progression. Thus, the objective of this article is, through a theoretical revision, to investigate and discuss the influence of communication practices and dynamics in the process of Personal Brand Management in social media, in order to contribute to overcome some of the gaps in scientific knowledge and enable the use of this knowledge by society in general.
- COVID-19’s Implications for accounting courses’ competence development: the case of PortugalPublication . Domingos, Alexandra; Sarmento, ManuelaOver the past few decades, higher education in accounting has been criticized for its focus on developing technical competences at the expense of general competences. The objective of this study is to analyze the general competences developed by the final-year students of accounting courses at Portuguese public polytechnics and to compare them with the most evident ones identified through a literature review for the current accounting profession. The study adopts a quantitative approach, carried out through a survey of 137 final-year students in the 2019/2020 academic year and using the techniques of descriptive and multivariate statistics. Among the main results, it was found that the ability to use information and communication technologies and lifelong learning were the most developed general competences. The results obtained allow us to conclude that the new practices developed through distance learning facilitated the development of technological competences, producing new reflections for improving the training of accountants.