Hydrogen-bonded low molecular weight gelators:structure-property relations

Gelen zijn unieke materialen, die welbekend zijn in het dagelijks leven en vele toepassingen kennen in o.a. voedingswaren, medicijnen, biomedische materialen en cosmetica. Voorbeelden van gelen die de meeste mensen bekend zullen voorkomen zijn gelatinepudding, vruchtengelei, anti-insect gel, haargel en wasmiddelgelen. Echter, hoe ziet zo'n gel er eigenlijk uit en waarom is het zo'n geleiachtige substantie? ... Zie: Samenvattin

Affectfullness as the basis for the (re)formulation of the teacher´s professional identity

‘Affectfullness’ is called the way of life defended by Theoretical System of Affectfullness (TSA) in which the interactions we experience in the world can become rich and meaningful. Seen in these terms, it may be understood as a method that provides parameters for analyzing our experiences and investing in our full development as human beings. As of this approach, the teaching and learning activities should also be seen from a broader perspective, since they have a relevant role in the developmental path of our species. Therefore, it is argued that in scholastic institutions, the teacher – the person in charge of ‘teaching’- needs to experience opportunities and perspectives of self-development which happens through participation in healthy interactions and appropriate conditions to carry out their work of transmitting the input of knowledge produced by humanity from generation to generation. However, unfortunately we have noticed that a large number of elementary school teachers in Brazil do not perceive themselves inserted in a context full of development possibilities, both of themselves and of their own students. Teachers experience discomfort and anxieties, which in turn result in disenchantment with their teaching activities. This paper aims to explore, based on the literature researched, some of the difficulties lived by performing teachers which were organized in seven sections that indicate how the integrity of the ‘teaching profession’ has negatively been affected. Then, it promoted a dialogue with the Theoretical System of Affectfullness (TSA) in order to elicit reflections, which contribute to the teachers arouse an “affectively expanded look” on the dimension of their daily work and their professional identity, becoming able to positively affect their work environment and help modify this reality for better

Exploring the impact of process parameters on the metal-free light-catalyzed ATRP polymerization of PVDF-based block copolymers

The synthesis of well-defined poly(vinylidene fluoride) (PVDF)-based block copolymers has been an important topic in recent years to accurately modify its properties and to achieve high-quality composites. Atom transfer radical polymerization (ATRP) proved itself to be a viable technique for the controlled synthesis of PVDF-based block copolymers. Recently, organic photoredox catalysts (OPRCs) have been reported as effective photocatalysts in light-catalyzed ATRP. Here, we use three OPRs (perylene, 10-methylphenotiazine, 10-phenylphenotiazine) for the ATRP of methylmethacrylate using telechelic PVDF as macroinitiators. We explore the impact of three process parameters: the end group on the polymer chain, the concentration of MMA, and the concentration of the OPRC in solution. First, three different telechelic PVDF were tested under the same monomer and OPRC concentrations to select the best macroinitiator for this system. Then, the effects on the overall control and on the conversion when the concentration of monomer or OPRC is varied were evaluated.</p