Contaminante em vinho: análise de ocratoxina A por cromatografia líquida de ultraeficiência e espectrometria de massas sequencial (UPLC®-MS/MS).

A ocratoxina A (OTA) é uma micotoxina carcinogênica e mutagênica que pode ser encontrada em uvas e vinho principalmente quando contaminados com Aspergillus carbonarius. A incidência de ocratoxina A nas amostras de vinho foi verificada usando uma metodologia baseada no método AOAC Official Method 2001.01, com quantificação por Cromatografia Líquida de Ultraeficiência CLUE/EM/EM. Dentre as 25 amostras de vinho avaliadas, a concentração média de OTA foi de 0,115 µg/kg e variaram na faixa de 0,059 - 0,455 µg/kg, todas estão abaixo do limite máximo tolerado recomendado pela legislação brasileira vigente (2 µg/kg para ocratoxina A em vinho).bitstream/item/119176/1/2014-CTec-201-Contaminante-em-vinho.pd

ENHANCEMENT OF MODE I FRACTURE TOUGHNESS OF ADHESIVELY BONDED SECONDARY JOINTS USING LAYUP PATTERNING OF CFRP

This work aims to analyse the influence of the CFRP layup patterning on the crack path of composite bonded joints and evaluate its effect on the mode I fracture toughness. An experimental program has been performed using Double Cantilever Beam tests with three different CFRP layup patterning and two adhesives. In addition, a finite element analysis was also implemented to further identify different damage mechanisms during the tests. The outcome shows that different substrate CFRP layup patterning results in distinct crack onsets and propagation paths during the tests, also influenced by the type of adhesive used. Furthermore, an enhancement of around 25% in the joint's onset fracture toughness was observed with the layup patterning compared to a reference joint (with unidirectional layup). Thus, the substrate's patterning morphology seems to be a promising method to increase the mode I fracture toughness of the studied secondary joints

A 1000-year-old mystery solved: Unlocking the molecular structure for the medieval blue from Chrozophora tinctoria, also known as folium

The molecular structure of the medieval watercolor known as folium has finally been solved in the 21st century. The interdisciplinary approach taken was the key to producing extracts that had been prepared following medieval instructions, and shows the blue/purple chromophore as the major dye in Chrozophora tinctoria fruits (shell). A multi-analytical characterization of its structure was made using HPLC-DAD-MS, GC-MS, NMR (1H, 13C, COSY, HSQC, HMBC, INADEQUATE), and computational studies. The results demonstrate that the blue compound corresponds to 6'-hydroxy-4,4'-dimethoxy-1,1'-dimethyl-5'-{[3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl]oxy}-[3,3'-bipyridine]-2,2',5,6(1H,1'H)-tetraone, a hermidin derivative, which we named chrozophoridin. Experimental data and computational modeling studies show that this mono-glycosylated dimer is represented by two stable isomers (atropisomers). This is an indispensable piece of knowledge for the characterization of this medieval dye in works of art such as medieval manuscript illuminations and for testing its stability and contributes to the preservation of our cultural heritage.info:eu-repo/semantics/publishedVersio

Production of non-toxic cellulose nanocrystals from grape pomace residue using a chemical-ultrasonic process.

SLACA, 12. De 4 a 7 de Novembro de 2017. Ref. 66611

Sumário Nacional de Touros da Raça Holandesa: 2004.

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Identificação laboratorial de staphylococcus aureus em leite bovino.

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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