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The processing of clay minerals consists, among other steps, in the removal of isolated mineral impurities, that is, not associated to crystalline structure of clay minerals, such as fractions of quartz and feldspars, originating from the process of soil formation. Thus, this work evaluated a sustainable method to reduction of isolated mineral impurities, in 4 in natura soil samples from Maranhão/Brazil, containing clay minerals. The method consisted of dispersing the samples only in water under high rotation and separating the impurities by sieving and decanting. The water and clay fraction were recovered from a manufactured solar evaporator and the clay fraction analyzed: X-ray diffraction (XRD) revealed a reduction in the intensities of mineral impurities, largely quartz, and a significant increase in the intensity corresponding to clay minerals; X-ray fluorescence (XRF) demonstrated a decrease in the SiO 2 /Al 2 O 3 ratio, indicating quartz removal; Fourier transform infrared analysis (FTIR) indicated removal of organic material; thermal analysis (TG/DTG) revealed an increase in the percentage of structural water loss, suggesting an increase in clay mineral content, and adsorption/desorption isotherms of N 2 demonstrated an increase in the surface areas and adsorption capacity of the benefited samples. The process yields obtained demonstrated compatibility with the particle size of the samples, with more expressive results for the more clayey ones. Thus, the investigated method, low cost and sustainable, proved to be viable and effective in obtaining clay minerals with reduced presence of isolated impurities, promoting considerable improvements in their properties, and favoring various technological applications, such as adsorption, heterogeneous catalysis, synthesis of mesoporous materials, among others. • A sustainable processing method for clay minerals has proven effective in reducing isolated impurities. • Significant reduction in the intensities of reflections from impurities and an increase in those from clay minerals. • Significant reduction of free quartz of in natura samples, with a decrease in the SiO 2 /Al 2 O 3 ratio. • Significant increase in the N 2 adsorption capacity and surface areas of the benefited samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ag 3 PO 4 /NiCo-MOF composites were obtained. • Staphylococcus aureus and Escherichia coli were inactivated by Ag 3 PO 4 /NiCo-MOF composites. • The 5%Ag 3 PO 4 /NiCo-MOF composite showed the best antibacterial property. In this paper, Ag 3 PO 4 /NiCo-MOF composites were synthesized with different mass contents of NiCo-MOF (5, 10, and 20wt%) from silver phosphate crystals (Ag 3 PO 4) and sheets of metal–organic frameworks of nickel and cobalt (NiCo-MOF). The materials were characterized, and their photocatalytic and bactericidal properties were evaluated against the bacteria Staphylococcus aureus (S. aureus) and Escherichia coli (E coli) incubated under exposure to white light emitting diode (WLED). X-ray diffraction (XRD) patterns of Ag 3 PO 4 and NiCo-MOF confirm the formation of crystals without a deleterious phase. Field emission scanning electron microscopy (FE-SEM) images showed polymorphism with shape predominant to tetrahedron-like Ag 3 PO 4 microcrystals and sheets for NiCo-MOF. The materials showed band gap energy values between 2.32 eV and 3.60 eV. Fourier-transform infrared (FTIR) spectroscopy shows the formation of molecular interaction between the materials. Bacterial susceptibility tests showed a reduction in Minimum Bactericidal concentration (MBC) values to 64 μg/mL when incubated with Ag 3 PO 4 under WLED exposure. The Ag 3 PO 4 /NiCoMOF-5wt% composite, incubated without light, showed MBC values of 64 μg/mL for S. aureus and 32 μg/mL for E. coli, respectively. Based on the results, the composite in the absence of WLED showed superior bactericidal results. [ABSTRACT FROM AUTHOR]

With this article, we aim to develop understandings about the knowledge produced at the stricto sensu postgraduate level in Brazil until 2020, in the wake of subjectivity and mathematical learning. For this, we carried out a state of knowledge type research, which has a basic, exploratory nature with a mixed approach and bibliographic character. Focused on production at the graduate level, we defined the Brazilian Digital Library of Theses and Dissertations and the Theses and Dissertations Catalog of the Coordination for the Improvement of Higher Education Personnel as databases, and, supported by the methodological approach adopted, we selected 17 works to compose the research corpus. The results of this study indicate a large concentration of productions in the South and Southeast regions of the country and programs in education. The production is dispersed, with a certain cohesion regarding the methodological nature of the research, since they are all qualitative, but plural in terms of the topics addressed, theoretical and methodological references, data production strategies, and results. Still, it is possible to point out that, despite the importance of the topic, the volume of works is not very expressive, indicating the need for more productions on the theme. [ABSTRACT FROM AUTHOR]

A new theory suggests that flammable gases generated by heated vegetation, in particular the volatile organic compounds (VOC) common to Mediterranean plants, may, under certain topographic and wind conditions, accumulate in locations where, after the arrival of the ignition source, they rapidly burst into flames as explosions. Hence, there is a need for the development of a system that can monitor the development of these compounds. In this work, a sensor's array is proposed as a method for monitoring the amount of eucalyptol and α-pinene, the major VOC compounds of the Eucalyptus and Pine trees. The detection of the target compounds was assessed using the impedance spectroscopy response of thin films. Combinations of layers of polyelectrolytes, such as poly(allylamine hydrochloride) (PAH), polyethyleneimine (PEI), poly(sodium 4-sytrenesulfonate) (PSS) graphene oxide (GO), and non/functionalized multiwall nanotubes (MWCNT-COOH or MWCNT), namely, PAH/GO, PEI/PSS, PEI/GO, PAH/MWCNT, PAH/MWCNT-COOH, films, and TiO2 and ZnO sputtered films, were deposited onto ceramic supports coated with gold interdigitated electrodes. The results showed that concentrations of the target VOCs, within the range of 68 to 999 ppmv, can be easily distinguished by analyzing the impedance spectra, particularly in the case of the ZnO- and PAH/GO-film-based sensors, which showed the best results in the detection of the target compounds. Through principal component analysis (PCA), the best set of features attained for the ZnO and PAH/GO based sensor devices revealed a linear trend of the PCA's first principal component with the concentration within the range 109 and 807 ppmv. Thus, the values of sensitivity to eucalyptol and α-pinene concentrations, which were (2.2 ± 0.3) × 10−4 and (5.0 ± 0.7) × 10−5 per decade, respectively, as well as resolutions of 118 and 136 ppbv, respectively, were identified. [ABSTRACT FROM AUTHOR]

Introduction: The nasolabial cyst is a rare disease, usually unilateral, benign, of embryonic origin, located in soft parts from the nasolabial folds and nasal wings. The diagnosis is essentially clinic, take into consideration the cyst topography, that is usually asymptomatic. Objective: This article has as main goal the description of a unusual case of nasolabial bilateral cyst with nasal obstruction, its treatment, anatomic pathological and accompaniment, besides the literature review. Case Report: Female patient, brown, 24 years old, showing bulging in nasolabial region and nasal obstruction. Physical and complementary exams with nasolabial cyst. Indicate surgical treatment of excision of the lesion. Final Considerations: The nasolabial bilateral cyst, although is rare, is a possible cause for the nasal obstruction, with good response to surgical therapy. [ABSTRACT FROM AUTHOR]

This paper presents a survey about several works in the field of predictive maintenance for hydroelectric power plants related to Assets Performance Management systems. It discusses about how to make a system study to better understand the structure of the Hydropower Plants and its components and how to define the most significant items to the maintenance. Also, it presents predictive maintenance techniques in terms of failure detection, diagnosis and prognostics. The research shows that data-driven methods are increasingly used by Hydropower Plants. With the recent development of artificial intelligence methods, it is possible to discover unknown patterns in sensor data and learn existing relationships in the data that may not be easy for a human to discover. In this way, some hybrid methods, which mix concepts such as the transformation of time series data into the frequency domain, statistical modeling and machine learning, are being developed to perform the tasks of APM systems. The work also shows the possibility of developing methods focusing on reinforcement learning or explainable artificial intelligence for the industrial sector. Such advances can count as a contribution to the innovative nature of the electricity sector, which tends to become increasingly sustainable in order to mitigate the environmental impacts caused by production. • APM systems are being used in combination with SCADA and ERP in Hydropower Plants. • Condition and Reliability based maintenance are base for developing APM systems. • Combining statistical modeling and machine learning methods in FDD for HPP is a trend. • There is a lack of artificial intelligence models focused on explainability for HPPs. [ABSTRACT FROM AUTHOR]