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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]

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]

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]

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]

Composed of hydrocarbons and other substances, petroleum is classified as a nonrenewable source of energy. In its unrefined form, it is called crude oil. Currently, its derivates are widely used in domestic and industrial environments, with the greatest exponent being motor fuels and lubricating oils. Due to the overwhelming demand, new oil wells in the presalt region of Brazil are going to be drilled, which will, in its turn, increase the demand for analysis and require the use of less costly technologies. The purpose of this paper is to present an experimental method that aims at characterizing crude oil samples through their X‐ray scattering profiles without the need for any chemical preparation to be performed in advance, which will enable this method to be used for analyzing samples immediately after their extraction. For the experiment, a portable X‐ray scattering system composed by an X‐ray tube (silver anode) and a Si‐PIN detector was used in order to analyze samples from different wells. The process consisted in establishing a linear relationship between the effective atomic number and the ratio between peak intensities of Compton and Rayleigh scattering from known samples. The linear function, verified experimentally, was then applied to samples of crude oil, and the results showed that it is possible to characterize them on the basis of the Rayleigh to Compton scattering ratio. After the analysis, a multiple comparison test performed on the samples proved that this methodology indeed allows to differentiate samples of different origins and to verify the compatibility of samples extracted from the same well. [ABSTRACT FROM AUTHOR]

Martian meteorites are excellent study materials for understanding the present and past of Mars, as they are important historical astrophysical artifacts because they possess information about Martian geological evolution and physical and chemical characteristics. In our case, we analyzed the NWA 6963 Martian meteorite classified as basaltic shergottite because of its chemical structure. A computerized microtomography (μCT) study in the NWA 6963 Martian meteorite provided us with 2D and 3D images that were extremely useful for ascertaining the internal structure of the analyzed sample and gave us the opportunity to find a crumpled material with a very peculiar structural format. In addition, it was possible to observe through the μCT that this encrusted material also has a completely different density of the meteorite. Calcium, strontium, and potassium were detected qualitatively, among others through the technique of X-ray fluorescence. [ABSTRACT FROM AUTHOR]

The determination of multielemental concentrations in physiological fluids is of considerable interest in clinical chemistry. Since it has been established these levels in human serum can be utilized as indicators for several pathological conditions. The multielement composition determination in human serum is important for the investigation of their role in human physiology and metabolism. From this research, more detailed studies on the health of individuals living in the metropolitan region of the state of Rio de Janeiro can be realized in order to improve the quality of life of these individuals. We studied 180 healthy volunteers (80 males and 100 females) aged 19 to 60 years. All the serum samples had been collected of people who live in the urban area of Rio de Janeiro City/Brazil. The measurements were performed at the X-Ray Fluorescence Beamline at the Brazilian National Synchrotron Light Laboratory (LNLS), in Campinas, São Paulo. We were able to determine the concentrations of the following 11 elements: Na, P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. In this study, we used statistical analysis for the principal components. We were able to verify the presence of two factors that divided the elements into two groups: group 1 formed by elements: Cl, K, S and Ca and group 2 by elements Cu and Zn. [ABSTRACT FROM AUTHOR]

Many objects of common use (tools, utensils, metals, knick-knacks, dishes and glasses) and artifacts (for example paintings of all types) are composed of two or more layers. In many cases, it would be useful to determine the correct location, composition and thickness of the various layers. Non-destructive and non-invasive methods are described, based on energy-dispersive X-ray fluorescence which are able to 'reconstruct' the complete structure of a multilayered sample. These methods use, in different ways, the ratios of characteristic X-rays emitted by the elements of the layers, and, in particular, two effects can be usefully employed, effects which are based on the differential attenuation of Kα and Kβ or Lα and Lβ X-rays: Different self-attenuation of K or L X-rays emitted by an element characterizing a layer because of the different energy of the two K or L X-rays;, Different attenuation of the two K or L X-rays of an element characterizing a layer by a second superimposed layer., Furthermore, the ratio of the Kα (or Lα) X-rays emitted by an element characterizing the internal layer, to the Kα (or Lα) X-rays emitted by an element characterizing a second superimposed layer, can also be employed in the 'reconstruction' of the layers. In this paper, the theoretical background of all these methods is described, and typical examples are shown. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]