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Artificial intelligence paradigms hold significant potential to advance nanophotonics. This study presents a novel approach to designing a plasmonic absorber using an artificial neural network as a surrogate model in conjunction with a genetic algorithm. The methodology involved numerical simulations of multilayered metal–dielectric plasmonic structures to establish a dataset for training an artificial neural network (ANN). The results demonstrate the proficiency of the trained ANN in predicting reflectance spectra and its ability to generalize intricate relationships between desired performance and geometric configurations, with values of correlation higher than 98% in comparison with ground-truth electromagnetic simulations. Furthermore, the ANN was employed as a surrogate model in a genetic algorithm (GA) loop to achieve target optical behaviors. The proposed methodology provides a powerful means of inverse designing multilayered metal–dielectric devices tailored for visible band wavelength filtering. This research demonstrates that the integration of AI-driven approaches in nanophotonics leads to efficient and effective design strategies.

In this {work}, the X-ray fluorescence technique was employed to characterize the pictorial materials used in two sculptures from the 18th. In addition, Raman spectroscopy was used to characterize the preparation layers used in the sculptures. {The analyzed sculptures} are carved in wood, with gilding and polychrome, and represent the biblical characters, Bathsheba, and King David. The sculptures are property of the Church of \textit{Nossa Senhora do Pilar}, in Duque de Caxias, RJ. XRF {analyzes} were performed using a portable ED-XRF system, which has a low-power X-ray tube (Amptek) with a silver target (Ag) and an SDD detector (Amptek). Raman spectroscopy {analyzes} were performed using the DXR2 Raman microscopy equipment (Thermo Fisher Scientific) with a 785 nm laser source. The results obtained from the XRF and Raman spectroscopy techniques suggest the presence of Gypsum, Calcite, Calcium Sulfate. In addition, the results obtained suggest the presence of the following pigments in the sculptures: Lead white, Titanium White, Lithopone, Ochre, Vermilion, Red Lead and gilding with gold leaf. The studies also showed that the Bathsheba sculpture was probably subjected to some processes of chromatic reintegration over the years due to the heterogeneity of pigments found in the same region

A Berlinda de Aparato do Imperador D. Pedro II é um objeto museológico muito importante para a história do Brasil. Trata-se do veículo imperial mais imponente de todo o período monárquico brasileiro, relacionado não apenas com a imagem do imperador D. Pedro II, mas com todo o Segundo Reinado. A berlinda foi encomendada para a cerimônia de coroação de D. Pedro II, em 1841 e pertence ao acervo do Museu Imperial, localizado na cidade de Petrópolis, Rio de Janeiro, Brasil. Neste trabalho foi analisado a técnica de douramento utilizada nas pinturas decorativas da berlinda. Para a análise do douramento foram aplicadas técnicas de Fluorescência de Raios X (XRF) e Macro Fluorescência de Raios X (MA-XRF). Todas as análises foram realizadas “in situ” utilizando equipamentos portáteis. As medidas de XRF realizadas sobre as folhas de ouro revelaram a presença do elemento-chave cromo. Os resultados combinados das técnicas analíticas utilizadas indicaram a possível utilização de mordente contendo amarelo de cromo como óleo adesivo para fixar as folhas de ouro nas pinturas decorativas. O resultado encontrado está de acordo com o descrito na literatura.

Abstract This study was aimed at the effects of different Creep-feeding protocols on piglet performance and its residual effects during the nursery phase. Experimental design used was five groups: WC (without creep); DCF (dry creep feeding); WCF (wet creep feeding); LD (additional liquid creep with automatic feed dispenser plus DCF); and LLF (additional liquid creep with linear feeder plus DCF). Ten litters per treatment were selected a total 50 sows and 645 piglets. During the first two weeks of lactation, the LD treatment (2.61 and 4.20 kg) promoted greater body weight (P

Plasmonic structures based on stacked layers of metal and dielectric materials excel as broadband absorbers because of the nonlinear relationship between the compound materials’ dispersion characteristics and the multilayered structure’s actual performance. In this work, radiation absorption along the plasmonic absorber is studied. Broadband absorptance spectra play an important role in applications such as photovoltaics, detectors, modulators, and emitters. We propose and analyze plasmonic stacked structures that exhibit high broadband absorption. For this purpose, an inverse design approach has been implemented using a conventional genetic algorithm as a global optimizer in conjunction with a pattern search as a local optimizer. The proposed strategy found structures with absorption covering the visible spectrum, maintaining its performance for high incident angles.

In this work, a commercial micro-XRF mapping equipment was adapted to, through data processing, map the characteristic X-ray transmittance throughout samples. The main difference for conventional tests is the production of characteristic x-rays on a metal base, and its detection on the other side of the sample. The transmittance measure can, therefore, be used to estimate, through equation systems, the layer thickness of each material that makes the sample. Samples of radiographic films were used, where the small thicknesses and the great difference in radiopacity between the materials (polyester and silver) are favorable for data acquisition. The results obtained show thickness maps whose values can be checked by other tools, such as micrometers. Such an approach can be extended to cases with more layers, but this directly implies the number of equations to be solved. The applicability can be used in many areas, depending on conditions of material and acquisition.

We describe here the synthesis of isoselenochromenes via a nucleophilic selenocyclization reaction of benzodiynes with sodium selenide. The central parameters that affect this cyclization reaction were studied, and the best reaction conditions were applied to different substrates to determine the scope of the method. The results indicated that isoselenochromenes were obtained in higher yields when the reactions were performed by the addition of NaBH4 (3 equiv), at room temperature, under nitrogen atmosphere, to a solution of elemental selenium (2 equiv) in dimethylformamide (2 mL). After 1 h, a benzodiynes (0.25 mmol) solution in EtOH (3 mL) was added at room temperature. The reaction was stirred at 75 °C until the starting material was consumed. The best conditions were applied to benzodiynes having electron‐rich, electron poor aromatic rings, and alkyl groups directly bonded to the alkynes. The same reaction condition was extended to isothiochromene derivatives but failed to prepare isotelurochromenes. The isoselenochromenes were easily transformed into three new classes of organoselenium compounds using classical methods available in the literature. We also conducted several control experiments to propose a reaction mechanism. [ABSTRACT FROM AUTHOR]

The oil industries have as main problem in their activities of formation of scales containing material of the naturally occurring radioactive material (NORM) type on the internal walls of pipes and in some equipment that make up the process lines plant. This NORM can contribute to the exposure of workers during routine activities, either through external exposure, or internal, through inhalation or ingestion. Considering the concern with occupational exposure, environmental impacts and the plant's production capacity, resulting from the formation of the scales, this work characterized samples of scale by means of techniques of x‐ray fluorescence (XRF), x‐ray diffraction (XRD) and high‐resolution gamma spectrometry. The XRF showed concentrations of P, S, Cl, Ca, Mn, Fe, Sr, and Ba as the main elements of the sample; the XRD showed calcite and barite as predominant composition; in the gamma analysis, the concentrations of the activities varied from 104.6 to 1112.6 Bq kg−1 for 226Ra and from 16.4 to 385.2 Bq kg−1 for 228Ra, within the limits set by the International Atomic Energy Agency. The indices radium equivalent activity, absorbed dose rate and annual effective dose indices varied from 128.4 to 1665.9 Bq kg1; 58.4 to 748.0 nGy h−1 and 0.072 to 0.918 mSv y−1, respectively. Only the effective dose values ​​were within the limits established by United Nations Scientific Committee on the Effects of Atomic Radiation, reinforcing the need for continuous monitoring on the platforms and the importance of keeping the radiological protection plan up to date, since the mobilization of NORM increases proportionally with the useful life of the production wells, thus increasing exposure indices. [ABSTRACT FROM AUTHOR]

Indiana limestone is composed mainly of calcite and aragonite minerals, which are different crystalline forms of calcium carbonate. Due to its composition of almost pure calcium carbonate (around 97%), it is widely used in the petroleum industry as a standard porous media for laboratory experiments with a huge scope in industrial applications. A method to improve oil recovery is associated with the use of nanoparticles (NP). One of the most promising is presented to be that of silica (Si) NP, because of their compatibility with the reservoir and subsurface abundance. In this work, we applied Si NP at a concentration of 0.5%, prepared in a base fluid of 1000 ppm in crude oil, injected in Indiana limestone and tested them with microtomography (microCT) and micro x‐ray fluorescence (microXRF) techniques to evaluate the impact of the treatment. Combining morphological results with the mapping of the elements, a more complete characterization of the sample is possible for a better understanding of these interactions applied in oil field industries. [ABSTRACT FROM AUTHOR]

Atmospheric particulate matter (PM) is considered to be a set of pollutants suspended in the air, from industrial processes, motor vehicle exhaust, resuspended street dust, biomass burning, and others. Among the toxic chemical compounds, PM is considered contaminants of great importance for researchers, as they offer harmful effects to humans, fauna and flora. Moreover, exposure to PM can cause the development and/or worsening of diseases, mainly respiratory and cardiovascular. The aim of the present study was to evaluate the metals concentration in total suspended particulate matter in the air through total reflection x‐ray fluorescence technique (TXRF). The samples were collected from random points in five neighborhoods in the Metropolitan Region of the state of Rio de Janeiro/Brazil. TXRF measurements were performed using the benchtop TXRF spectrometer S2 PICOFOX. The results showed that the proposed methodology was able to detect the elements Cr, Fe, Ni, Cu, and Zn, in concentrations ranging from 2.0 to 200 ng.m−3. It can be concluded that the study methodology for determining the metal concentrations in air samples is an efficient and low‐cost solution for studying environmental pollution. [ABSTRACT FROM AUTHOR]

Bread is one of the oldest foods of mankind, and among them, the sandwich bread is worldwide known and used. In this study we used the non‐destructive computed microtomography technique (microCT) to evaluate the behavior of bread structure over weeks after the production. In addition, the influence of the storage location of the sandwich bread, we performed a comparative analysis between storage at ambient temperature and refrigerated conditions. The analysis of the reconstructed images shows that the bread suffers loss of structure over the weeks. We also have found that keeping the bread refrigerated loses liquid, drying the bread, and thus increasing the loss of its structure. In addition, the porous structure of the bread was evaluated, and a complete characterization of the microstructural changes was performed over time. [ABSTRACT FROM AUTHOR]

The culture of coffee is very important in Brazilian scenery. Brazil is the world's largest coffee producer, responsible for 30% of the planet's production, and it is among the 15 largest coffee consuming nations. More and more, consumers look for better quality of coffee, and the presence of determinate composts would prejudice the health of the consumers. Therefore, this study suggests a method to identify and quantify commercially roasted ground coffee impurities/contaminants using computed microtomography (micro‐CT) and x‐ray fluorescence (XRF) techniques. A set of different commercially roasted ground coffees were investigated. The micro‐CT results showed that most of the coffee powder samples analyzed showed some contaminant, and in a specific brand, the amount of contaminants was higher than 9%. The 3D data provided information about the size and shape of these contaminants. The XRF results showed the macro elements P, S, Cl, K, and Ca and the micro elements Mn, Fe, Cu, Zn, Rb, and Sr. The elemental concentrations are in agreement with the values reported in the literature, except for the same specific brand, where the values found were much higher. The combined data of both techniques showed that the amount of impurities/contaminants in the ground coffee results in an increase of the macro and micro nutrients and also modifies the flavor and fragrance of the product, leading to an overall poor quality of the final beverage. [ABSTRACT FROM AUTHOR]