Abstract One of the solutions in civil construction to increase the life cycle of buildings is the ventilated facade due to its technical characteristics. Large porcelain tiles are used as a coating in this system, raising questions about its performance. This study used real size porcelain tiles (590 mm × 1190 mm) for pressure tests to evaluate the deformation suffered by the material at different pressure points, according to NBR 10821. In addition, the strength of the glass fiber-reinforced ceramic tiles has been tested against the impacts of rigid and soft bodies in a hidden clamp ventilated system, according to NBR 15575. Due to the wind, the system presented maximum deformation of 1.7 ±0.4 mm. When subjected to impacts, the system functioned within the norm for hard body strikes (20 J), meeting the requirements against minor proportions and wind pressures of up to 1480 Pa. Unsatisfactory performance when impacted by a soft body was observed. Such results show that the system needs to improve regarding resistance to major impacts.

Abstract A thermosetting epoxy polymer composed of diglycidyl ether of bisphenol A and triethylenetetramine (DGEBA/TETA) was modified by incorporating flexographic photopolymer plate residues (rubber microparticles). The photopolymer plate residues were processed in two ways: (a) by grinding and performing particle size classification (where the resulting samples were denoted PP) and (b) by polyester layer separation and grinding the elastomeric fraction by cryogenic grinding (where the resulting samples were denoted ER). Both residual particles were incorporated into the epoxy at concentrations of 2.5, 5 and 7.5 wt%. The main results indicate that PP was not efficient as a modifier of the epoxy system. A reduction in mechanical properties (maximum tensile strength and deformation) was observed in the samples produced with PP in different concentrations. But, when the ER is incorporated, an increase in tensile property and in the deformation capacity, as well as impact resistance was observed in samples produced with ER. Scanning electron microscopy analysis showed a greater presence of voids in formulations produced with PP, which corroborates the decrease in the tensile strength of these samples.

Civil construction seeks to increase the useful life of the facades of buildings. Installing a ventilated facade is one way to accomplish this due to aesthetic and technical advantages. Ceramic tiles are the main products used as the covering. To the back face of a tile, a bidirectional screen of glass fiber is adhered using epoxy resin. This set forms a composite for security reasons. During the last decade, there has been an increase in the substitution of composites of synthetic fibers with those of natural fibers. The present work compares the fire-resistant behavior of glass fiber with that of jute fiber applied to ceramics installed in ventilated facade. The following conjoint composites were produced: glazed porcelain tile, epoxy resin, glass fiber and jute fiber screens. In this work, it was verified that the jute fiber did not present advantages regarding the exposure to fire in comparison with the glass fiber.

RESUMO Nanomateriais exibem propriedades que se aplicam nas mais variadas áreas, entre estas, na área da saúde e agrícola, nas quais as pesquisas vêm aumentando progressivamente. Neste trabalho sintetizamos nanopartículas de sílica não porosas dopadas com óxido de cobre (CuO) usando método de Stöber com pequenas modificações. Em adição, a atividade antimicrobiana destes compostos contra Staphylococcus aureus, Escherichia coli e Candida albicans foi avaliada. Primeiramente, o nanomaterial foi caracterizado por difração de raios-X para identificação da fase CuO na matriz de sílica, e espectroscopia no infravermelho por transformada de Fourier identificando as principais bandas do SiO2 e a funcionalização do CuO. Por fim, a morfologia das partículas foi observada por microscopia eletrônica de varredura a qual mostrou formação de nanopartículas esféricas com tamanho aproximado de 70 nm. As nanopartículas de sílica dopadas com CuO mostraram eficiência na inibição dos três tipos de microrganismos testados neste trabalho, formando halos de inibição entre 19,0 e 25,0 mm. Nos ensaios de adsorção usando azul de metileno, foi possível observar que a presença de CuO na superfície das nanopartículas de sílica modificou as características de adsorção, aumentando a capacidade e a cinética de adsorção e desta forma mostrando ser um nanomaterial com características interessantes para aplicações na agricultura e em diferentes áreas da saúde.

ABSTRACT Nanomaterials exhibit properties that apply in a wide range of area, including health and agriculture, where research is progressively increasing. In this work we synthesize non-porous silica nanoparticles doped with copper oxide (CuO) using Stöber's method with small modifications. In addition, the antimicrobial activity of these compounds against Staphylococcus aureus. Escherichia coli and Candida albicans was evaluated. First, the nanomaterial was characterized by X-ray diffraction to identify the CuO phase in the silica matrix, and Fourier transform infrared spectroscopy identifying the main SiO2 vibration bands and the CuO functionalization. Finally, the particle morphology was observed by scanning electron microscopy which showed formation of spherical nanoparticles size ~70 nm. CuO-doped silica nanoparticles showed efficiency in the inhibition of the three types of microorganisms tested in this work, forming inhibition halos between 19.0 and 25.0 mm. In the adsorption tests using methylene blue, it was possible to observe that the presence of CuO on the surface of the silica nanoparticles modified the adsorption characteristics, increasing the adsorption capacity and kinetics and thus showing to be a nanomaterial with interesting characteristics for applications in the agriculture and in different areas of health.

The aim of this study was to evaluate the effect of an 11.6Li2O-16.8ZrO2-68.2SiO2-3.4Al2O3 (LZSA) glass ceramic on the grain growth of alumina obtained by pressureless sintering. Three contents of the LZSA glass ceramic (7, 15, and 21 vol%; mean particle size of 1.52 µm) and three types of alumina (mean particle sizes of 0.5, 1.7, and 2.8 µm) were used. The powder compositions were formed by cold pressing. The samples (5 mm × 5 mm × 13 mm) were sintered in an optical dilatometer. The grain size and morphology were evaluated by scanning electron microscopy. The results show that elongated alumina particles were obtained for the investigated composites compared with pure alumina because of the LZSA addition. The grain growth of alumina was less pronounced at higher LZSA contents. High relative densities were obtained for higher LZSA contents at lower temperatures and holding times compared with pure alumina.