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In Brazil, the cashew-nut industry has an important role in national economy, but the lack of suitable treatment of the residues generated by this activity represents a serious risk to the environment and biodiversity. Cardanol (CDN) is a highly toxic and recalcitrant phenolic compound, and it is the major component from this activity. This work evaluated, for first time, the performance of mixed metal oxide DSA ® -type anodes (Ti/TiO 2 -RuO 2 and Ti/TiO 2 -RuO 2 -IrO 2 ) to develop a suitable electrochemical treatment for the cashew-nut industry residues, using CDN as model molecule. Results clearly showed that for both Ti/TiO 2 -RuO 2 and Ti/TiO 2 -RuO 2 -IrO 2 active anodes, an increase on the current densities ( j ) enhanced the percentage of total organic carbon (TOC) removal as a function of the electrolysis time ( t ). The complete TOC removal was efficiently achieved with Ti/TiO 2 -RuO 2 ( j ≥ 40 mA cm −2 and t ≥ 5.0 h) at 25 °C, although Ti/TiO 2 -RuO 2 -IrO 2 ternary anode has also showed suitable performance for this purpose ( j = 60 mA cm −2 and t ≥ 4.0 h). UV-visible spectrophotometric data showed similarity between the CDN electrooxidation kinetics for both anodes, independently of the applied current density. Analyses performed by gas chromatography coupled to mass spectrometry confirmed the complete mineralization of CDN and its intermediates, mainly at higher densities. A positive effect in the degradation performances was achieved when an increase on the temperature was attained, at both anodes; despite the satisfactory results achieved at 25 °C, favor an affordable cost. [ABSTRACT FROM AUTHOR]

Titanium (Ti) is considered a contaminant of emerging interest, as it displays toxic potential and has been increasingly employed in everyday products, pharmaceuticals, and food additives, mainly in nanoparticle form. However, several knowledge gaps are still noted, especially concerning its dynamics in the water. In this context, this study aimed to quantify total Ti concentrations in highly consumed swimming crabs, squid, and shrimp from an important estuary located in southeastern Brazil. Ti concentrations were higher than those reported in most studies carried out worldwide. Animal length and weight, as well as, depth, transparency, dissolved oxygen, and salinity, significantly influence Ti concentrations in the animals. Human health risks were also noted after calculating a simulated exposure to titanium dioxide, especially considering the uncertainties regarding the effects of this element and the absence of regulatory limits. • Titanium is used in many everyday products and is considered an emerging contaminant. • Titanium was quantified in muscles samples of swimming crab, shrimp, and squid. • Biometric and abiotic factors influence Titanium concentrations in the animals. • The metal concentrations found here were higher than in other works around the world. • The assessment of exposure to Titanium indicated potential risk to human health. [ABSTRACT FROM AUTHOR]

The faker makes use of several strategies to give credibility to his work, as for example by copying artist's style or by using artificial aging techniques. The characterization of artistic materials, such as pigments, binding media and supports through chemical and/or physico-chemical analysis, coupled with art historical information is essential to establish the non-authenticity of works of art. This paper presents a contribution in a legal case regarding paintings attributed to important Brazilian and European artists such as Candido Portinari, Juan Gris, Camille Pissarro, and Umberto Boccioni, among others. In the investigation, modern synthetic painting materials were identified in all the ground layers of the suspected paintings. The use of diverse instrumental analytical techniques such as Fourier transform infrared spectroscopy, polarized light microscopy and pyrolysis-gas chromatography/mass spectrometry enabled this characterization. The results demonstrated the presence of titanium dioxide, calcium carbonate and kaolin as inorganic components of the paints, and polyvinyl acetate copolymerized with vinyl versatates or diisobutylphtalate as binding media in the ground layers of the paintings. The results obtained, along with art historical information and art technological studies, were very important in the judicial process, due to the possibility to use titanium dioxide and polyvinyl acetate copolymerized with vinyl versatates as chronological markers. [ABSTRACT FROM AUTHOR]

Abstract: Supergene aggregates of platinum–palladium (Pt–Pd) intermetallic compounds from the Córrego Bom Sucesso alluvial deposit, Minas Gerais, Brazil, are coated with abundant, poorly crystalline nanoparticles of anatase (TiO2). The anatase coating is widespread, suggesting that the surface of the Pt–Pd grains catalytically destabilised Ti, which was likely dissolved by organic ligands in the ground waters. Association of TiO2 nanocrystallites with organic matter further suggests that biogenic processes could have mediated their formation. These anatase-coated Pt–Pd grains demonstrate an unexpected Ti mobility in supergene environments. [Copyright &y& Elsevier]

The School of Mines Museum of Science and Technology of the Federal University of Ouro Preto has, in its collection a fragment of an iron meteorite weighing 110.76g named Itumirim. It was found near Itutinga, a village distant 228km from Belo Horizonte in the state of Minas Gerais. SEM analysis, coupled with EDS (Energy Dispersive Spectrometry) showed that the structural class of the studied Itumirim fragment is medium octahedrite, Om. The mineralogical phases were determined using EDS and Mössbauer Spectroscopy (Miniaturized Mössbauer Spectrometer - MIMOS II). Theses studies provided information for classifying the meteorite as belonging to the IIIAB group, the same classification as the Itutinga meteorite. [ABSTRACT FROM AUTHOR]

The durability of unplasticized poly(vinyl chloride) (uPVC) components used in the building industry is a function of the interaction of several factors. Types and quantities of additives incorporated to the PVC resin and defining the formulation of the PVC compound used in the production of these components are among the most important such factors. White uPVC window profiles with different formulations have been exposed to five years of natural weathering under Brazilian climatic conditions. Results of Charpy impact tests were used to assess the influence of three factors on the durability of the profiles: additivation levels of titanium dioxide, nature of the impact modifier, and nature of the thermal stabilizer. Statistical analysis of the results made it possible to rank these factors according to their influence in component durability. The influence of composition of uPVC on mechanical properties of window profiles is demonstrated by means of the study of the modulus of elasticity. Results presented in this paper indicated the need for several additional experiments in order to check changes in molecular mass and color. Comparison of all these data with results from profiles subjected to accelerated weathering led to straightforward criteria for prediction of the potential behavior of uPVC, to be described in a future paper. [ABSTRACT FROM AUTHOR]

The Areado Granite-Migmatite Unit is part of the basement from the Southern Brasilia Orogen at southwestern São Francisco Craton margin, outcropping between Alfenas and Areado regions, Minas Gerais State, Brazil. This unit is composed of garnet meta-syenogranite, hornblende-garnet metatexite, and stromatic diatexite with different degrees of partial melting. This study characterizes the garnet meta-syenogranite, its migmatitic counterparts and investigates the different patterns of deformation and partial melting involved to produce the observed migmatites within the unit. The connection between the garnet meta-syenogranite, hornblende-garnet metatexite, and biotite diatexite is inferred from field observations and assemblage of accessory minerals. Petrography associated with modal analysis, structural data, quartz c-axis analysis, zircon U–Pb (LA-MC-ICP-MS and SHRIMP) dating, as well as trace elements chemical analysis in quartz and titanite to determine metamorphic, partial melting, and deformation evolution were used as tools in this investigation. The garnet meta-syenogranite has a crystallization age of 2069.8 ± 5 Ma. Lower intercepts from zircon indicate a metamorphic and partial melting age between 671 ± 58 and 657 ± 40 Ma. Melt crystallization ages are inferred between 622 ± 7 Ma and 604 ± 6 Ma. Different rates of partial melt are structurally connected, being higher at the base of the unit, and are related with contrasting amounts of water influx and deformation. The deformation during metamorphism/partial melting was the main cause of the differential aspect of the produced rocks. Quartz c-axis thermometer yielded deformation temperatures of 765–935 °C and other pulses occurred between 590 and 715 °C, both between 11 and 15 kbar. Those values match the Zr-in-titanite thermobarometer data, which is 670–710 °C for low-temperature titanite and 785–815 °C for high-temperature crystals. These data indicate that the protolith was generated at a Rhyacian late magmatic stage of the Mineiro Belt and passed by a Neoproterozoic deformational-metamorphic event of high temperature. • Applying quartz c-axis thermometer implied in two deformation temperature intervals, one that represents the metamorphic peak, between 766 and 892 °C, and a lower one, between 613 and 714 °C. • The application of TitaniQ, together with Zr-in-Titanite, did not produce consistent results for these rocks when 0.5 titanium activity was applied. When a 0.2 TiO 2 activity is used, the metamorphic peak reaches 770–820 °C and 11.5–15 kbar. • TitaniQ, Zr-in-Titanite, and quartz c-axis thermometers correlations suggest a progressive deformational-metamorphic pulse. • The metamorphic ages obtained for this unit (671–621 and 604-557Ma) might represent the changes in the melting process. • Crystallization age of 2.08–2.07 Ga of the protolith indicates it's coincident with the late stages from the Mineiro Belt. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the apparent total tract digestibility (ATTD) and the standardized total tract digestibility (STTD) of P, and their respective digestible values, of two high protein (HP) corn dried distillers' grains (DDG) and of two corn DDG with solubles (DDGS), from Brazil and USA, in pigs. Fifty crossbred barrows (38.3±5.2kg BW) were fed a semi-purified P-free basal diet (BD), used to determine endogenous P losses, or four diets composed of 40% of each ingredient, as the only source of P, substituting for starch in BD: Brazilian HP DDG (BHP); USA HP DDG (UHP); Brazilian DDGS (BDG) and USA DDGS (UDG). Animals were fed at 2.8 x maintenance (110 kcal of DE per kg of BW0.75) for 9 d (7 d adaptation and 2 d of partial feces collection). Titanium dioxide was used as an indigestible marker (0.3%) for digestibility calculations. A randomized block design was used, with 10 replicates, using the pig as the experimental unit. Results were submitted to ANOVA and Tukey's test (P< 0.05). The ATTD of P of UHP and UDG were 47% greater (P< 0.05) than those verified in BHP and BDG. The STTD of P of UHP and UDG were 45% higher (P < 0.05) than that of BDG. The STTD of BHP was similar (P >0.05) to the values of BDG and UDG. The total and standardized digestible P of UDG (0.40-0.44%, respectively) were greater (P< 0.05) than those of BDG (0.33-0.38 %, respectively) and of UHP (0.28-0.32%, respectively), which were similar (P > 0.05), and higher than that of BHP (0.22-0.27%, respectively). In conclusion, corn distiller's co-products from Brazil and USA presented different ATTD and STTD P values, and USA DDGS (UDG) showed the highest apparent total tract and standardized digestible P among all corn coproducts evaluated. [ABSTRACT FROM AUTHOR]

The article describes a platinum quartz with a six-rayed star from Brazil. Examination of the stone confirmed its formation by a combination of two titanium oxide minerals, rutile and brookite, included in rock crystal and light brown smoky quartz from Curvelo in Minas Gerais State. Lapidary and jewelry designer Kevin Lane Smith displayed the quartz at the Tucson gem shows in Arizona.