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Chemical modification as a strategy to modulate properties of oxypropylated pro...

Nowadays a great interest is devoted to the production and use of biobased products. The main scope of the oxypropylation process is to obtain polyols, in the form of viscous liquids, which can be interesting co-monomers to produce polyurethanes and polyesters. Due to the high hydroxyl content of natural polymers (suitable substrates to be oxypropylated), the generated polyols are multifunctional, hence most ad...

Exotic manganese dioxide structures in niobium oxides capacitors

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Panorama Nacional do Bullying

Influence of carrier concentration on the control of Galactomyces geotrichum bu...

The present work aims to evaluate a strategy to solve Galactomyces geotrichum bulking based on the incorporation of a biofilm carrier in activated sludge systems. For this study, four sequencing batch reactors (SBR) were operated without (SBR1) and with a carrier for biofilm growth (5% [SBR2], 10% [SBR3], and 20% [SBR4] of the reactor volume). As expected, G. geotrichum bulking was observed in the SBR operating...

New polyurethanes from oxypropylated olive stone

The purpose of this work is to explore the possibility of chemically modifying the generated polyols (oxypropylated olive stone) through reactions with isocyanates to produce polyurethanes, other than rigid polyurethane foams. This could be achieved by the chemical modification of the oxypropylation products (condensation with isocyanates) by using mono and difunctional reagents to modulate properties and/or pr...

Search for novel biobased materials within the OLIVPOL project

Within the context of the project OLIVPOL, olive stone (OS) residue was successfully converted into viscous polyols, as such, or containing reinforcing stone cores, by total or partial oxypropylation, respectively. Moreover, the synthesis of new macromolecular materials using the oxypropylated products, such as polyesters and polyurethanes, demonstrated a promising approach to the production of original value-a...

Estratégias pedagógicas segundo o Projeto Optimist na aprendizagem da escrita

Relatório apresentado para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Educação Pré Escolar.

Datação, autenticidade, materiais e pigmentos. Estudos laboratoriais sobre faia...

The oxypropylation of olive stone and the use of the ensuing polyols for th...

The development of polyols by the oxypropylation of abundant and renewable vegetable and animal resources constitutes an original approach to the exploitation of the biomass. Cellulose, starch, chitosan, chitin, different types of lignins, cork and more complex structures like sugar beet pulp, are among the documented examples. All these systems displayed a similar pattern in terms of the grafting of short poly...

Blue pigments in XVI-XVII century glazes : a comparative study between portugue...