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Consensus exists among researchers and academics that science education, including chemistry education, is fundamental to the development of modern societies. Thus, investment becomes essential, from early years, in the education of informed citizens, prepared with scientific literacy competences and able to pursue an active, participative and responsible citizenship. In this context, school plays a major role and should provide chemistry education for all children. As such, it is necessary that teachers are able to meet this need and ensure the implementation of innovative practices, which, according to current guidelines, should be based in investigative activities of practical and experimental nature with a science-technology-society orientation, whose scientific contents are closely related to certain social phenomena (economics, politics and environment) and that meet the interests of children by helping them to explain and interpret the world around them. In this paper, we aim to present a review on the current guidelines for education in chemistry in the early years, that is, in pre-school and primary school, by applying a methodology based on practical and experimental work.

This paper presents a short overview of teacher´s training as considered by the Portuguese legislation: (i) initial teacher education (ITE), (ii) specialized training and (iii) in-service teacher training. A particular emphasis will be given to in-service teacher training. Nowadays, ITE corresponds to level 7 of the European Qualifications Framework (master degree). It is a career-long professional development, where research-based and in context practice are important features. Specialized training is intended to provide qualification in complementary educational functions, such as special education, school administration and inspection activities, socio-cultural animation and basic education for adults. In-service training or continuous training allows teachers to complement, deepen and update their knowledge and professional competences. Its accreditation, in what concerns involved institutions, training actions and evaluation process is centralized in the "Conselho Científico-Pedagógico da Formação Contínua" (Scientific and Pedagogical Council of in-service training) and has a direct impact in teacher's careers, being one of the factors considered to access mobility and progression.

The temperature and enthalpy of fusion of choline chloride -[Ch]Cl- are not directly measurable since this compound decomposes upon melting. Yet, given the wide use of this compound in the preparation of deep eutectic solvents (DES), its thermophysical fusion properties are very important for a better understanding of these mixtures and the thermodynamic description of their solid-liquid phase diagrams. In this work, the fusion properties of choline chloride were estimated using the solubility curves of choline chloride in ten different ionic compounds, forming simple binary eutectic mixtures with quasi-ideal liquid phases. Experimental solid-liquid equilibria data for these systems -[Ch] Cl + ionic compounds- were measured, and the ideality of the systems assessed through the quantification of the activity coefficients and their comparison in each pair of binary solutions. The values estimated for the fusion properties of choline chloride are T fus,[Ch]Cl = 597 ± 7 K and Δ fus H [Ch]Cl = 4300 ± 600 J mol −1 . These were additionally checked by thermodynamic consistency tests and by the prediction of the solid-liquid curves with COSMO-RS model. The results obtained with both procedures allow us to guarantee the usefulness and robustness of the estimated data. ; This work was developed in the scope of the project CICECOAveiro Institute of Materials, POCI-01-0145-FEDER-007679 (Ref. FCT UID/CTM/50011/2013) and Project POCI-01-0145-FEDER- 006984 e Associate Laboratory LSRE-LCM, both funded by FEDER through COMPETE2020 - Programa Operacional Competitividade e Internacionalizaç~ao (POCI) e and by national funds through FCT - Fundaç~ao para a Ci^encia e a Tecnologia. M.A.R.M acknowledges FCT for her PhD grant (SFRH/BD/87084/2012). J.O. and L.F. thank the financing provided by the Spanish Government, Ministerio de Economia y Competitividad (MINECO), under the project CTQ2012- 37114 and the short-stay grant EEBB-I-16-11792. ; info:eu-repo/semantics/publishedVersion

Bio-contamination of water through biofouling, which involves the natural colonization of submerged surfaces by waterborne organisms, is a global socio-economic concern, allied to premature materials bio-corrosion and high human health risks. Most effective strategies release toxic and persistent disinfectant compounds into the aquatic medium, causing environmental problems and leading to more stringent legislation regarding their use. To minimize these side effects, a newly non-biocide-release coating strategy suitable for several polymeric matrices, namely polydimethylsiloxane and polyurethane (PU)-based coatings, was used to generate antimicrobial ceramic filters for water bio-decontamination. The best results, in terms of antimicrobial activity and biocide release, showed an expressed delay and a decrease of up to 66% in the population of methicillin-resistant Staphylococcus aureus bacteria on ceramic filters coated with polyurethane (PU)-based coatings containing grafted Econea biocide, and no evidence of biocide release after being submerged for 45 days in water. Biocidal PU-based surfaces were also less prone to Enterococcus faecalis biofilm formation under flow conditions with an average reduction of 60% after 48 h compared to a pristine PU-based surface. Biocidal coated filters show to be a potential eco-friendly alternative for minimizing the environmental risks associated with biofouling formation in water-based industrial systems. ; info:eu-repo/semantics/publishedVersion

Bio-contamination of water through biofouling, which involves the natural colonization of submerged surfaces by waterborne organisms, is a global socio-economic concern, allied to premature materials bio-corrosion and high human health risks. Most effective strategies release toxic and persistent disinfectant compounds into the aquatic medium, causing environmental problems and leading to more stringent legislation regarding their use. To minimize these side effects, a newly non-biocide-release coating strategy suitable for several polymeric matrices, namely polydimethylsiloxane and polyurethane (PU)-based coatings, was used to generate antimicrobial ceramic filters for water bio-decontamination. The best results, in terms of antimicrobial activity and biocide release, showed an expressed delay and a decrease of up to 66% in the population of methicillin-resistant Staphylococcus aureus bacteria on ceramic filters coated with polyurethane (PU)-based coatings containing grafted Econea biocide, and no evidence of biocide release after being submerged for 45 days in water. Biocidal PU-based surfaces were also less prone to Enterococcus faecalis biofilm formation under flow conditions with an average reduction of 60% after 48 h compared to a pristine PU-based surface. Biocidal coated filters show to be a potential eco-friendly alternative for minimizing the environmental risks associated with biofouling formation in water-based industrial systems. ; This research work was supported by national funds through FCT-Foundation for Science and Technology within the scope of research units grants to BioISI (UIDB/04046/2020 and UIDP/04046/2020), and also by Base Funding-UIDB/00511/2020 of the Laboratory for Process Engineering, Environment, Biotechnology, and Energy-LEPABE-funded by national funds through the FCT/MCTES (PIDDAC). O. Ferreira also acknowledges the Grant PD/BD/128370/2017. L.C.G. and E.R.S. thank the Portuguese Foundation for Science and Technology (FCT) for their work contracts through the Scientific ...