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Formulation and Characterization of a Composite Coating Formulation Based on Ac...

Sandra Monteiro; Nuno Ferreira; Diana Paiva; Susana P. Silva; Jorge Martins; Luísa H. Carvalho; Fernão D. Magalhães


Pulegone and Eugenol Oral Supplementation in Laboratory Animals: Results from A...

Carla M. Ribeiro Silva; Ana I. Faustino Rocha; Rui M. Gil da Costa; Rui Medeiros; Maria J. Pires; Isabel Gaivão; Adelina Gama; Maria J. Neuparth

Essential oils are natural compounds used by humans for scientific purposes due to their wide range of properties. Eugenol is mostly present in clove oil, while pulegone is the main constituent of pennyroyal oil. To guarantee the safe use of eugenol and pulegone for both humans and animals, this study addressed, for the first time, the effects of these compounds, at low doses (chronic toxicity) and high doses (...


Effect of spent sulfite liquor on urea-formaldehyde resin performance

Ana Maria Ferreira; João Pereira; Margarida Almeida; João Ferra; Nádia Paiva; Jorge Martins; Luísa H. Carvalho; Fernão D. Magalhães

Combination of urea-formaldehyde (UF) resins with technical lignins has been often reported in the literature. However, the actual implications of this approach have not been effectively addressed yet. In this work, unmodified thick spent sulfite liquor (TSSL) and hydroxymethylated TSSL (TSSLH) were incorporated in a standard UF resin in different amounts (10 and 20%) and at different stages. When 10% of TSSLH ...


Low-cost natural binder for particleboards production: study of manufacture con...

Ana M. Ferreira; J. Pereira; Margarida Almeida; J. Ferra; N. Paiva; Jorge Martins; Fernão D. Magalhães; Luísa H. Carvalho

Nowadays, the majority of adhesives used in particleboards (PB) manufacture are formaldehyde-based. In the present research work a low-cost bioadhesive, based on the combination of thick spent sulfite liquor (TSSL) with wheat flour, was tested for the production of three-layer particleboards, at different conditions (particleboards target density, pressing time, pressing temperature, wood type and binder age). ...


Classification of amino resins and formaldehyde near infrared spectra using K-n...

Miguel Gonçalves; N. T. Paiva; J. M. Ferra; Jorge Martins; Fernão D. Magalhães; Luísa Carvalho

Amino resins are synthetic adhesives that can be divided into three major types: urea-formaldehyde (UF), melamine-urea-formaldehyde (MUF), or melamine-formaldehyde (MF). When less than 5% of melamine is added to a UF resin, the resin is called a melamine-fortified UF (mUF) resin. The extensive application of these resins in wood-based products is due to their many advantages: ease of use, strong bonding, resist...


Preparation of carbon molecular sieve membranes from an optimized ionic liquid-...

Sandra C. Rodrigues; Márcia Andrade; Jamie Moffat; Fernão D. Magalhães; Adélio Mendes

Novel carbon molecular sieve membranes with high separation performance and stability in the presence of humidified streams were prepared from an optimized ionic liquid-regenerated cellulose precursor, in a single carbonization step. Membranes prepared at two different carbonization end temperatures (550 degrees C and 600 degrees C) were analyzed through scanning electron microscopy, thermogravimetric analysis,...


Impact of alkaline-acid and strongly acid process on the synthesis of urea-form...

Carolina Gonçalves; João Pereira; Margarida Almeida; Nádia T. Paiva; João M. Ferra; Jorge Martins; Fernão D. Magalhães; Ana Barros Timmons

This paper presents the impact of different processes for producing urea-formaldehyde resins and their roles on the physico-mechanical properties and the formaldehyde emission of the resulting particleboards. Five resins were produced: four via the alkaline-acid process (Resin A to D) and one using the strongly acid process (Resin E). The differences between the syntheses are mainly related to different formald...


Intramedullary nailing biomechanics: Evolution and challenges

Natacha Rosa; Miguel Marta; Mário Vaz; Sérgio M. O. Tavares; Ricardo Simões; Fernão D. Magalhães; António Torres Marques

This article aims to review the biomechanical evolution of intramedullary nailing and describe the breakthrough concepts which allowed for nail improvement and its current success. The understanding of this field establishes an adequate background for forthcoming research and allows to infer on the path for future developments on intramedullary nailing. It was not until the 1940s, with the revolutionary Kuntsch...


Low density wood particleboards bonded with starch foam-study of production pro...

Sandra Monteiro; Jorge Martins; Fernão D. Magalhães; Luísa Carvalho

It has been shown that wood particleboards bonded with sour cassava starch can display low density combined with good physico-mechanical performance, thanks to starch being able to produce a strong foam that fills the interparticular space. Here we optimize the pressing conditions for the production of these panels. The procedure involved hot-plate pressing in two stages: (1) lowering the top platen to a specif...


Carbon Membranes with Extremely High Separation Factors and Stability

Sandra Rodrigues; Márcia Andrade; J. Moffat; Fernão D. Magalhães; Adélio Mendes

For some time, carbon molecular sieve membranes (CMSMs) have been promoted as energy-efficient candidates for gas separation due to their high selectivity, permeability, and stability in chemically aggressive environments. Nevertheless, these membranes have not yet been made into commercial products due to a significant decrease in performance when exposed to humidity and/or oxygen. Herein, disruptive CMSMs wit...


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