Spectrophotometric characterization of simple glazings for a modular façade

A large variety of transparent materials is available for uses in buildings façades and all glazing properties must be considered in their choice. Such a selection should be a careful process of evaluation and weighing of tradeoffs. The correct glazing specifications for façades can reduce energy consumption in buildings, because the heat exchange and passage of radiation into the building as light and heat occur through transparent surfaces. Therefore, glazing significantly contributes to the heat transfer between outdoor and indoor spaces, which act directly on daylighting and thermal comfort. This manuscript addresses a spectrophotometric characterization of glazings for the study of components for the design of a modular façade system based on the climate of Portugal. The study focused on results of spectrophotometric measurements of an optical behavior in different solar spectrum intervals (ultraviolet, visible and near infrared), specifically the transmittance of some types of simple glazings. The results show the percentage of transmission to spectrum intervals, which enabled the analysis (OK?) of the efficiency of the glazing regarding daylighting and correlation to the thermal performance. Indications for specifications and adequate uses based on transmission of transparent surfaces have been obtained and complemented the datasheets available from the manufactures.The authors gratefully acknowledge the financial support provided by Erasmus Mundus ISAC – Improving Skills Across Continents for this research.info:eu-repo/semantics/publishedVersio

Study of tinctorial behaviour of curaua and banana fibres

The ecological benefits of renewable raw materials are clear: they save valuable resources, are environmentally sound and do not cause health problems. Natural fibres have already established a track record in several different areas such as, civil, automobiles, architecture, medicine among others. Numerous investigations are carried out in order to create added value to natural fibre materials such as the stem of the banana tree that are usually discarded in the environment. Curaua, another important natural substrate, is an Amazon-forest plant (Ananas erectifolius) that resembles a pineapple plant. Curaua leaf fibres display a low-production cost and offer a relatively high tensile strength level. Despite these naturals fibres are well established as reinforce in composite materials, the dyeing properties of curaua and banana fibres are not well studied yet.This work is supported by Portuguese National Funding, through FCT - Fundação para a Ciência e a Tecnologia, on the framework of project UID/CTM/00264/2013

Antibacterial Effect of Silver Nanoparticles on Klebsiella spp

Silver nanoparticles (AgNP) can be incorporated into medical devices, such as tissues, to circumvent bacterial resistance such as Klebsiella spp, which can lead to skin and mucosal infections. Thus, the aim of the present study was to synthesize silver nanoparticles for later incorporation into cotton fabrics and in vitro tests against Klebsiella spp. The AgNP colloidal solution was synthesized (AgNO3 - 0.1 mM, 100 mM trisodium citrate, polyvinylpyrrolidone - 0.24 g, H2OH2) and then impregnated into the cotton fabric pretreated with poly diallyl dimethylammonium chloride (PDDA) of 100/500 tissue, shaken for 30 minutes). The material produced was analyzed by the FTIR; DLS and reflectance spectroscopy. The tests of the antimicrobial activities were by the microdilution technique against Klebsiella spp, in tubes containing Brain Heart Infusion (BHI), with the solution of silver (1); Tissue containing AgNP - 4 mm (2); Negative control (3) and positive control - ceftriaxone (4). Regarding MIC, the inhibitory activity occurred of the dilutions between 1/2 and 1/16. The AgNP particles had an average size of 24.75 nm. As synthesized AgNPs demonstrate the excellent antimicrobial activity against Klebsiella spp, with special emphasis on applications in nanotechnology and nanomedicine, targeting multiresistant antibiotic bacteria

Production of photocatalytic road pavements using TiO2 nanoparticles

posterMan’s activity and mismanagement of resources conducted to dangerous levels of pollution in water, air and earth and to incalculable deficiencies, harmful to the physical and social health of mankind. Industrial activities, heating systems and road traffic are the main responsibles for the emission of pollutant gases such as nitrogen oxides (NOx) and volatile organic compounds (VOCs). As so, its harmful impacts are observed far beyond large cities and jam-packed streets. It is important to refer that the health costs related only with road traffic air pollution represents 0.9%-2.7% of the gross domestic product (GDP) in France, for example. Under this context, the combination of nanostructured titanium dioxide (TiO2) and bituminous formulations represents a tool, with considerable degree of innovation, towards the reduction of environmental impacts. In this work, conventional hot mix asphalt (HMA) was produced with standard materials to play the role of a control sample. Afterwards, an aqueous solution of TiO2 nanoparticles was sprayed over sample’s surface. By another hand, a HMA samples was also modified through the volume incorporation of small quantities of TiO2 nanoparticles and recycled glass cullets. It is expected that the inclusion of glass in the asphalt formulations should promote an in-depth conduction and entrapment of light , thus enhancing the photocatalytic performance of this samples. Scanning Electron Microscopy (SEM) analysis were conducted in order to infer about the morphology of the modified HMA samples and the surface as well as the in-depth dispersion of TiO2 nanoparticles and recycled glass cullets. The produced samples were also subjected to wearing tests using the tire-road contact method. Before and after the wearing process, the photocatalytic efficiency was evaluated via the decomposition rate of an aqueous solution of Methylene Blue (MB) under UV light irradiation

USO DE HIDROGEL DE ÁLCOOL POLIVINÍLICO: REVISÃO BIBLIOGRÁFICA

O Álcool Polivinílico (PVA) é um polímero artificial biocompatível e importante sistema para a liberação controlada de medicamentos. Assim, objetivou-se discorrer sobre a utilização do hidrogel de Álcool polivinílico (PVA) e suas aplicações microbiológicas. Trata-se de uma revisão de literatura integrativa sobre a temática. Observou-se que o PVA pode ser mesclado com outros polímeros como a quitosana para a constituição de hidrogel ou filme, na qual se incorporam antimicrobianos para liberação controlada. Dentre os resultados favoráveis a atividade antimicrobiana de sistemas com PVA, o mais frequente foi contra as bactérias Staphylococcus aureus e Escherichia coli. Assim, esses sistemas demonstram-se alternativas de baixo custo e eficiência para uso frente a resistência bacterian

O impacto da SARSCOV-2 no ensino dequímica no município de Barcarena –PA / The impact of SARSCOV-2 on chemistry teaching in the municipality of Barcarena -PA

A presente pesquisa tem como objetivo analisar como os discentes e docentes estão lidando com o ensino remoto de química no município de Barcarena-PA, mediante novos encaminhamentos, em especifico, em tempos de pandemia, por meio de práticas que resgatem a formação continuada, através de atividades Síncronas e Assíncronas. Também tem em vista, mostrar as estratégias que foram adotadas e rever métodos de ensino aprendizagem, com o intuito de englobar todos os discentes, fazendo com que os mesmos possam usufruir da internet como ferramenta auxiliar para seu ensino.  Como metodologia essa pesquisa foi conduzida pelo método qualitativo, por meio de pesquisa colaborativa. Esta pesquisa foi realizada em escolas públicas, que é onde há uma maior dificuldade por parte dos discentes, utilizando formulários on-line próprios para discentes, docentes e coordenadores, com o objetivo de estudar como cada um está lidando com a pandemia no ensino remoto. Os resultados mostraram que em tempos de pandemia e distanciamento social, a aproximação virtual parece ser a melhor escolha no processo educativo, apesar de ainda haver discentes que não possuem acesso a plataformas de ensino e consequentemente não conseguem acompanhar o desenvolvimento das aulas. Contudo, a motivação entre os envolvidos é fundamental para aumentar a confiança e manter o ensino e aprendizagem. 

USO DE HIDROGEL DE ÁLCOOL POLIVINÍLICO: REVISÃO BIBLIOGRÁFICA

O Álcool Polivinílico (PVA) é um polímero artificial biocompatível e importante sistema para a liberação controlada de medicamentos. Assim, objetivou-se discorrer sobre a utilização do hidrogel de Álcool polivinílico (PVA) e suas aplicações microbiológicas. Trata-se de uma revisão de literatura integrativa sobre a temática. Observou-se que o PVA pode ser mesclado com outros polímeros como a quitosana para a constituição de hidrogel ou filme, na qual se incorporam antimicrobianos para liberação controlada. Dentre os resultados favoráveis a atividade antimicrobiana de sistemas com PVA, o mais frequente foi contra as bactérias Staphylococcus aureus e Escherichia coli. Assim, esses sistemas demonstram-se alternativas de baixo custo e eficiência para uso frente a resistência bacterian

Physical, Chemical and Morphological Characterization of Polyamide Fabrics Treated with Plasma Discharge

<div><p>In this work, physical, chemical and morphological modifications of three different polyamide 6.6 (PA6.6) fabrics were investigated using double barrier dielectric (DBD) plasma treatment. Several techniques of characterization were used to study the effects caused by the interaction between plasma discharge and polyamide fabrics, such as: contact angle, water drop adsorption, Energy Dispersive Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), whiteness by Berger degree and tensile strength. All analyses performed in this study showed that DBD plasma discharge, when applied on PA6.6 fiber, produces significant modifications on the surface of this substrate, without altering its intrinsic properties, thus proving the effectiveness of this important technology to the textile industry.</p></div

Promotion of photocatalytic activity onto building facades through the application of TIO2 based nanolayers

posterUrbanism and communities centralization enlarges atmospheric pollution decreasing the health quality of human beings and affects the aesthetical appearance building’s façades. Apart from health related consequences, pollution leads to façade soiling and staining that represent considerable maintenance costs and structures degradation. Consequently, metropolitan planners face the concern of increasing functional housing spaces forecasting at the same time the application of sustainable construction concepts. The application of a heterogeneous photocatalysis has been pointed as a potential technology to be applied for self-cleaning and de-pollution solutions. Photocatalytic activities arise from the photocatalytic properties of employed semiconductor materials. Titanium dioxide nanocoatings are, by fare, the widely used as a consequence of its powerful oxidation strength, chemical stability, non toxic properties and availability. Although there is a considerable number of techniques to deposit TiO2 based materials, few of them have potential market application for civil construction industry. For this particular application prototype scale up may be as smooth as possible with relative small implementation costs. In this sense, the deposition of TiO2 nanoparticles (TiO2-NNPs) using liquid based techniques (e.g. spin coating and/or dip coating) may be a feasible solution to produce facade’s materials with self-cleaning and de-polluting abilities. Moreover, it is consensual in scientific community that the presence of anatase phase enhances photocatalytic activity of coated materials. Furthermore, the formulation of solutions using TiO2-NNPs with bulk anatase crystalline structure will eliminate the heat treatment step generally required to achieve it. In this study, TiO2 nanoparticles based layers were deposited onto different ceramic materials using dip-coating and magnetron sputtering method.s The colourless layers were deposited onto gray and white ceramic substrates without changing their aesthetical appearance. The photocatalytic activity (degradation of pollutants adsorbed on the surface) of the TiO2-NNPs based layers was characterized via the decomposition rate of an aqueous solution of Methylene blue (MB) under UV light irradiation. The highest photocatalytic performance was achieved for the coated gray ceramics; a photodegradation rate of and a photocatalytic efficiency of 83% was found. The mentioned coated sample allowed the attainment of a moderate self-cleaning ability and a noticeable photodegradation capacity

Azilsartan increases levels of IL-10, down-regulates MMP-2, MMP-9, RANKL/RANK, Cathepsin K and up-regulates OPG in an experimental periodontitis model.

AimsThe aim of this study was to evaluate the effects of azilsartan (AZT) on bone loss, inflammation, and the expression of matrix metallo proteinases (MMPs), receptor activator of nuclear factor κB ligand (RANKL), receptor activator of nuclear factor κB (RANK), osteoprotegerin (OPG), cyclooxygenase-2 (COX-2), and cathepsin K in periodontal tissue in a rat model of ligature-induced periodontitis.Materials and methodsMale Wistar albino rats were randomly divided into 5 groups of 10 rats each: (1) nonligated, water; (2) ligated, water; (3) ligated, 1 mg/kg AZT; (4) ligated, 5 mg/kg AZT; and (5) ligated, 10 mg/kg AZT. All groups were treated with saline or AZT for 10 days. Periodontal tissues were analyzed by histopathology and immunohistochemical detection of MMP-2, MMP-9, COX-2, RANKL, RANK, OPG, and cathepsin K. Levels of IL-1β, IL-10, TNF-α, myeloperoxidase (MPO), and glutathione (GSH) were determined by ELISA.ResultsTreatment with 5 mg/kg AZT resulted in reduced MPO (pConclusionsThese findings reveal that AZT increases anti-inflammatory cytokines and GSH and decreases bone loss in ligature-induced periodontitis in rats