Search

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]

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]

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]

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]

Diseases of the prostate gland are the most frequently diagnosed in men after middle age. Spheroid cell culture is a useful technique for tissue engineering or regenerative medicine research, pharmacological and toxicological studies, and fundamental studies in cell biology. In this paper, we investigated zinc distribution in cell spheroids in benign prostate hyperplasia (BPH) and prostate cancer (PCa) (DU145) and analyzed the differences in the response to zinc (0–150 \mu \textM ) treatment using $\mu $ XRF with synchrotron radiation. The results showed nonuniform distribution of Zn in all the spheroids analyzed. The differential response to zinc of BPH and DU145 cell spheroids suggests that zinc may have an important role in PCa. [ABSTRACT FROM PUBLISHER]

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]

Three types of alloys were recognized when analyzing pre-Columbian artifacts from the North of Peru: gold, silver, and copper alloys; gilded copper and silver; silvered copper; tumbaga, i.e., copper or silver enriched on gold at the surface by depletion gilding. In this paper, a method is described to differentiate gold alloys from gilded copper and from copper–gold tumbaga, and silver alloys from silvered copper and copper–silver tumbaga. This method is based on the use of energy-dispersive X-ray fluorescence, i.e., on a sophisticated analysis of XRF-spectra carrying out an accurate determination of Cu( Kα/ Kβ), Ag( Kα/ Kβ), Au( Lα/ Lβ), and Au- Lα/Cu- Kα or Ag- Kα/Cu- Kα ratios. That implies a dedicated software for the quantitative determination of the area of X-ray peaks. This method was first checked by a relevant number of standard samples and then it was applied to pre-Columbian alloys from the North of Peru. [ABSTRACT FROM AUTHOR]

In this work the pigments, ground layer and the structure of a polychrome wooden Pietà sculpture from the 18th century was characterized using X-ray fluorescence and computed microtomography (microCT) techniques. It was possible to detect the elements: Ca, Ti, Fe, Cu, Zn, Ba, Au, Hg and Pb. It was possible to characterize the pigments Azurite, Prussian Blue, Green Earth, Vermilion, Lead white, Zinc white, and Gold foils. In the regions where there were restorations, it was possible to identify the presence of the lithopone pigment, indicating that these processes occurred from the 19th century. The microCT showed that the statue is a carved wood sculpture with a painting layer with high density pigments. Two different blocks of wood were identified joined together with a wooden pin. The statue was attached to its wooden base with different types of nails, showing that this step took place in a period of time later than the statue manufacturing. Details of the attaching of the eyes and damages due to insect galleries could be also found in this statue. • Cultural heritage objects analysis using X-ray fluorescence (XRF) and microCT) techniques. • Analysis of the internal structure of a wood sculpture using the microCT technique. • The microCT technique identified a base later added to the sculpture. • The XRF technique characterized of the pigments and the preparation layer. • The XRF technique allowed to characterize restoration areas. [ABSTRACT FROM AUTHOR]

Abstract: An X-ray Transmission Microtomography (CT) system combined with an X-ray Fluorescence Microtomography (XRFCT) system was implemented in the Brazilian Synchrotron Light Source (LNLS), Campinas, Brazil. The main aim of this work is to determine the elemental and absorption distribution map in breast tissue samples. The experiments were performed at the X-Ray Fluorescence beamline (D09B-XRF) of the Brazilian Synchrotron Light Source (LNLS), Campinas, Brazil. A quasi-monochromatic beam produced by a multilayer monochromator was used as an incident beam. The fluorescence photons were acquired with an energy dispersive HPGe detector (CANBERRA Industries Inc.) placed at to the incident beam, while transmitted photons were detected with a fast Na(Tl) scintillation counter (CYBERSTAR Oxford Danfysik) placed behind the sample in the beam direction. All the tomographic images were reconstructed using a filtered-back projection algorithm. [Copyright &y& Elsevier]

In this work, 960 réis coins from the period when Brazil was a colony of Portugal were analyzed using the x-ray fluorescence (XRF) spectrometry. The history of these coins, dated between the end of the 17th century and the beginning of the 19th century, had a great influence on the immigration of the Portuguese Prince Regent D. João to Brazil, who arrived in 1808. Bearing in mind the need to expand the timid Brazilian monetary system, the Portuguese crown decided to collect Spanish silver pesos of 8 reales , recoined with a value of 960 réis. The recoinage procedure was carried out using a stamp; therefore, in many cases, it is possible to check the base currency. In this work, were investigated 17 samples of 960 réis coins by XRF, in which the base coin was 8 reales manufactured with raw materials from Mexican mines. In addition to characterizing the elemental composition of the coins, the XRF data were evaluated using multivariate statistical method of Robust Principal Component Analysis (ROBPCA), which was used to classify the coins based on their elemental composition. However, with XRF, elementary information is obtained for a depth of only a few micrometers. One of the essential issues in Ag–Cu metal alloys is the Ag enrichment, which can cause changes to the elemental composition of the surface. Therefore, initially, a study was carried out to verify whether the surface compositions of the coins were altered by the Ag enrichment. Image 1 • Analysis of Brazilian coins of 960 réis by XRF. • Robust Principal Component Analysis (ROBPCA) applied to XRF data. • Ag enrichment study by XRF. [ABSTRACT FROM AUTHOR]

The pigments characterization in artwork and cultural heritage is important since it allows to reveal many information like the period characteristics in which the object was made, its provenance and its manufacturing technique. Furthermore, it can support in the identification of forgeries and in the evaluation of conservation and restoration interventions. In this work, it was used XRF, μXRF, XRD and Raman spectroscopy techniques in the characterization of a statuette of the "Nossa Senhora da Conceição Aparecida". The X-ray fluorescence analysis were performed in 66 points distributed throughout the piece, like in the wood structure, in the ground layer and on the pigment layer. In addition, elemental mapping was performed using the X-ray micro fluorescence (μXRF) technique in a small fragment, containing both the pigment and the ground layer. The X-ray diffraction analyzes were performed on the ground layer material and the Raman spectroscopy was performed in order to improve the evaluation of the data and assist in the characterization of the ground and the pigment layers. The results show that the major elements in the pigment were Fe and Mn, indicating that it's probably the Burnt Sienna pigment. The XRD and Raman analysis show that the substrate layer was made by calcium carbonate (calcite) and a binder material (probably rabbit glue). • The study and characterizations of the pigments, ground layer and structure of an statuette. • Pigment characterization by XRF techniques. • Pigment and ground layer characterization by the Raman spectrometry technique. • Assist the restauration team to decide the best way to preserve and restore the statuette. [ABSTRACT FROM AUTHOR]