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Traces from bodies can be of various nature, for example of biological or inorganic origin. Some of these historically have received more consideration than others in forensic practice. Samplings of gunshot residues or biological fluid traces are commonly standardized, whereas macroscopically invisible environmental traces are usually ignored. This paper simulated the interaction between a cadaver and a crime scene by placing skin samples on the ground of five different workplaces and inside the trunk of a car. Traces on samples were then investigated through different approaches: the naked eye, episcopic microscope, Scanning Electron Microscopy (SEM) with Energy-dispersive X-ray spectroscopy (EDX) and Energy Dispersive X-Ray Fluorescence (ED-XRF). The purpose is to provide the forensic scientist with the awareness of the value of debris on skin and then to highlight implications for forensic investigations. Results demonstrated that even naked eye observation can reveal useful trace materials, for defining the possible surrounding environment. As a next step, the episcopic microscope can increase the number of visible particulates and their analysis. In parallel, the ED-XRF spectroscopy can be useful to add a first chemical composition to the morphological data. Finally, the SEM-EDX analysis on small samples can provide the greatest morphological detail and the most complete chemical analysis, although limited, like the previous technique, to inorganic matrices. The analysis of debris on the skin, even with the difficulties due to the presence of contaminants, can provide information on the environments involved in criminal events that can add to the investigation framework.

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This work presents the geochemical characterization of two Martian analogues located in the Basque-Cantabrian Basin: Enekuri and Fruiz. In contrast to previous works carried out on the coastline analogues Meñakoz and Armintza (Biscay, Spain), these new outcrops are not in contact with sea-water nowadays. Hence, the weathering processes observed in Enekuri and Fruiz (inland) are different from those observed in Armintza and Meñakoz (coastline). In this way, among all the mineral phases found the only ones in common between inland and coastline outcrops are albite and chlorites, minerals that were formed in aqueous conditions. Understanding the differences presented in both types of outcrops could help to interpret the future results from the missions Mars2020 and the ExoMars2022, since coastline outcrops are affected by sea-water weathering and inland outcrops are altered by the high biological activity.

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Heavy metal contamination in raw materials has spread widely in the United States. The high increased number of recalls in consumer products and the lack of stricter regulations in the raw materials to be used in the jewelry industry have raised concerns among consumers. Studies in low-cost jewelry have shown the presence and high content of heavy metals; this environmental problem led to a child's death after swallowing a charm containing elevated levels of lead (Pb). Exposure to heavy metals, through inhalation, mouth, and skin contact, causes adverse health effects in children and adults. Exposure to lead affects mainly the nervous system and brain development; exposure to cadmium (Cd) causes damage to liver, kidneys, and lungs, and potentially leads to cancer; exposure to nickel (Ni) causes severe dermatitis. Thus, the importance and impact of studies of this nature cannot be overstated. As heavy metal contamination has increased in the United States, this research fills an important knowledge gap between previous studies conducted on low-cost jewelry and fine jewelry. In this study, conducted in the Paso del Norte region, one hundred and forty-three pieces of fine jewelry were evaluated for the presence of heavy metals using X-ray fluorescence (XRF) spectroscopy. Our study showed that 61 samples (42.7 %) exhibited the presence of Ni in the metal alloy, prevailing in jewelry pieces with lower percentage of gold. Eighteen samples showed the presence of Pb in gemstones, 11 pieces of these samples (7.7 % total) had <33.3 % gold (≤10 K); however, none of the samples showed the presence of Pb in the metal alloy. Further research is needed to evaluate the bioaccessibility of Pb in these gemstones, which may pose a potential health hazard to children and adults in the US Paso del Norte region and throughout the world.

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Cultural and religious heritage assessments and restorations are considered to be a fundamental requirement of any modern society because these constructions represent one of the most meaningful and tangible connections to our past. With rare exceptions, heritage buildings were built with materials and systems that could bear gravitational loads but not bending and shearing resulting from seismic loading. Thus, in many cases, earthquake ground motions have led to severe degradation and even the collapse of various parts of these structural systems. In order to address these issues, repair and replacement techniques are applied as common parts of restoration work. In the peculiar case of stone masonry structures, a standalone macroscopic examination is not self-assured and, most often, can lead to an inadequate selection of a replacement material. Therefore, a knowledge of mesoscopic, petrographic, physical and mechanical properties is compulsory in the design, planning and execution of restoration work. From this perspective, the present research has taken, as a case of study, the Frumoasa monastic complex from Iași, Romania, introducing microscopic, XRF (X-ray fluorescence) spectroscopy and petrographically based approaches, comparing three limestone samples with a sample dislodged from the original wall. The physical properties (bulk and real densities, open porosity and capillary water absorption coefficient) and the mechanical properties (compressive and tensile strengths) were also experimentally determined. The samples were extracted from stone quarries located on the territories that were part of the same historical region as the Frumoasa monastic complex. Based on the outcomes of this study, suitable criteria for the stone replacement-consisting of identifying the main structure, quarry rock petrographical parameters and physical and mechanical characteristics-were determined and applied.

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X-ray fluorescence (XRF) spectroscopy offers a fast and efficient method for analysing soil elemental composition, both in the laboratory and the field. However, the technique is sensitive to spectral interference as well as physical and chemical matrix effects, which can reduce the precision of the measurements. We systematically assessed the XRF technique under different sample preparations, water contents, and excitation times. Four different soil samples were used as blocks in a three-way factorial experiment, with three sample preparations (natural aggregates, ground to ≤2 mm and ≤1 mm), three gravimetric water contents (air-dry, 10% and 20%), and three excitation times (15, 30 and 60 s). The XRF spectra were recorded and gave 540 spectra in all. Elemental peaks for Si, K, Ca, Ti, Fe and Cu were identified for analysis. We used analysis of variance (anova) with post hoc tests to identify significant differences between our factors and used the intensity and area of the elemental peaks as the response. Our results indicate that all of these factors significantly affect the XRF spectrum, but longer excitation times appear to be more defined. In most cases, no significant difference was found between air-dry and 10% water content. Moisture has no apparent effect on coarse samples unless ground to 1 mm. We suggested that the XRF measurements that take 60 s from dry samples or only slightly moist ones might be an optimum option under field conditions.

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Non-invasive techniques (X-ray fluorescence, XRF, and Raman spectroscopy) were used for the study of the Hispano Muslim wall paintings. Principal component analysis (PCA) was performed on the semi-quantitative XRF results directly provided by the in-built factory calibrations with minimum user manipulation. The results obtained were satisfactory and highlighted differences and similarities among the measurement points. In this way, it was possible to differentiate the decorations carried out on gypsum plasterwork and the wall paintings over lime plaster. The color palette, revealed by combining the results from XRF and Raman spectroscopies, comprised the pigments hematite, lapis lazuli, cinnabar (in poor conservation state), and possibly, carbon. Evidence of past interventions was also provided by PCA on XRF data, which detected the presence of Pb, Ba, and Zn in some areas. Furthermore, the preparation layers have been studied in detail on cross-sections of two microsamples. Several layers of lime plaster with a compact microstructure have been observed. The characteristic of the pictorial layer and the identification of calcium oxalate point to the use of a secco-technique. The main alteration identified was a gypsum surface layer covering the painting and signs of plaster deterioration due to gypsum migration to more internal areas. Finally, the comparison with the observations made by restorers in previous interventions on these paintings revealed the importance of the representativeness gained with the in situ study, which enabled the analysis of a high number of areas.

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In this paper, an in-depth and systematic study of the radiological characterization of three types of Puglia region natural limestones (Pietra Leccese, Pietra Mazzara and Carparo) was carried out. The investigation was performed by XRF spectroscopy for a chemical analysis, and gamma spectroscopy of the specific activity concentration of natural radionuclides 226Ra, 232Th, and 40K. Although the limestone does not fall within the category included by Italian Legislative Decree 101/2020, the gamma index was calculated using the results of the gamma spectroscopy measurements. For Pietra Mazzara and Carparo stones, the gamma index was found to be less than the reference value; conversely Pietra Leccese was found to be higher. To obtain a more complete evaluation of the external exposure, radium equivalent activity and external radiation hazard were calculated for all analyzed stones. The results suggest the need to broadly consider the radiological risk for these stones, and for limestone more generally, when used as a building material.

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Among the thousands of existing rice varieties, aromatic rice has increasingly attracted consumer's preference in recent years. Within aromatic rice, Basmati, cultivated in some regions in Pakistan and India, is highly demanded. Other aromatic rice, cultivated in specific regions, for instance in Thailand (commonly referred to as Jasmine Thai rice), are also highly appreciated by consumers. In this work, the elemental profiles of commercially available rice samples (17 Basmati, 11 Thai, and 7 Long Grain rice) were determined by energy-dispersive X-ray fluorescence (ED-XRF) spectroscopy. The mass fractions of P, Cl, S, K, Fe, Cu, and Zn were significantly different (95% confidence interval) between Basmati and Thai rice and between Thai and Long Grain rice; only Cl, S, and Zn were significantly different between Basmati and Long Grain rice. Multivariate evaluation of the results combining soft independent modelling by class analogy (SIMCA) and partial least square discriminant analysis (PLS-DA) allowed the correct classification (true positives) of 94.1, 85.6, and 100% of the Basmati, Long Grain, and Thai rice, respectively. The specificity (true negatives) of Basmati, Long Grain, and Thai was 94.4, 82.1, and 100%, respectively.

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Soil contamination by potentially toxic elements (PTEs) is intensifying under increasing industrialization. Thus, the ability to efficiently delineate contaminated sites is crucial. Visible-near infrared (vis-NIR: 350-2500 nm) and X-ray fluorescence (XRF: 0.02-41.08 keV) spectroscopic techniques have attracted tremendous attention for the assessment of PTEs. Recently, the application of fused vis-NIR and XRF spectroscopy, which is based on the complementary effect of data fusion, is also increasing. Moreover, different data manipulation methods, including feature selection approaches, affect the prediction performance. This study investigated the feasibility of using single and fused vis-NIR and XRF spectra while exploring feature selection algorithms for the assessment of key soil PTEs. The soil samples were collected from one of the most heavily polluted areas of the Czech Republic and scanned using laboratory vis-NIR and XRF spectrometers. Univariate filter (UF) and genetic algorithm (GA) were used to select the bands of greater importance for the PTE prediction. Support vector machine (SVM) was then used to train the models using the full-range and feature-selected spectra of single sensors and their fusion. It was found that XRF spectra alone (primarily GA-selected) performed better than single vis-NIR and fused spectral data for predictions of PTEs. Moreover, the prediction models that were derived from the fused data set (particularly the GA-selected) enhanced the models' accuracies as compared with the single vis-NIR spectra. In general, the results suggest that the GA-selected spectra obtained from the single XRF spectrometer (for As and Pb) and from the fusion of vis-NIR and XRF (for Pb) are promising for accurate quantitative estimation detection of the mentioned PTEs.

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The authenticity of tea has become more important to the industry while the supply chains become complex. The quality and price of tea produced in different regions varies greatly. Currently, a rapid analytical method for testing the geographical origin of tea is missing. XRF is emerging as a screening technique for mineral and elemental analysis with applications in the traceability of foodstuffs, including tea. This study aims to develop a reliable multivariate classification model using XRF spectroscopy to obtain the mineral content. A total of 75 tea samples from tea producing countries throughout the world were analysed. After variable shortlisting, 18 elements were used to construct the multivariate models. Tea origin was determined by classifying the tea into 5 major geographical regions producing most of the global tea. PCA showed initial clustering in some regions, although the types of teas included in the study (black, green, white, herbal) showed no discrete cluster membership. The prediction power of each classification model developed was determined by using two multivariate classifiers, SIMCA and PLS-DA, against an independent validation set. The average overall correct classification rates of PLS-DA models were between 54-85% while the results of SIMCA models were between 70-84% resolving the poor clustering initially shown by PCA. This study demonstrated the potential of geographical origin of tea prediction using elemental contents of tea. Naturally, the classification can be linked not only to origin but to the type of tea as well. PRACTICAL APPLICATION: Wholesalers and retailers need a rapid and robust screening tool to confirm the origin and type of tea they sell to consumers. X-Ray fluorescence spectroscopy proved a good technique for achieving this in commercial teas sourced worldwide. Building on multivariate models, broad classification was accomplished both in terms of origin (Asian vs non-Asian) and in tea type with zero sample preparation and low cost of analysis.

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This paper studies the mechanical properties of porous asphalt concrete with styrene-butadiene-styrene (SBS) polymer modified bitumen as the binder, steel slag as the aggregate and crumb rubber and basalt fiber as modifiers. First, the appearance, mechanics, chemical composition and high-temperature stability of steel slag were studied by some equipment. Then, three kinds of porous asphalt concrete with SBS polymer modified bitumen as binder were produced, Namely, crumb rubber modified porous asphalt concrete (CR-PAC), basalt fiber modified porous asphalt concrete (BF-PAC), and basalt fiber and crumb rubber composite modified asphalt concrete (CM-PAC). Finally, the properties of the three kinds of modified PACs were studied through the Marshall test, freeze-thaw splitting test, low-temperature splitting test, permeability test, and creep test. The results showed that the crush value and abrasion value of steel slag are 15.1% and 13.5%, respectively; it has excellent strength and abrasion. In addition, the steel slag shows a porous structure and it provides an interface basis for a better bond with bitumen. For the three PACs, the results showed that the Marshall stability, water stability, and low-temperature crack resistance of CM-PAC are all the best Furthermore, CM-PAC has better rutting resistance than two single modified PACs, based on creep test results. The CM-PAC in this study can be used as a new type of pavement material.

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The authentication of the packaging represents an important step in the investigation of suspected counterfeits of pharmaceutical products. The visual comparison with a retained sample is the first step to detect a counterfeited packaging. Due to the improvement of technologies like printing, the emergence of counterfeits with a better appearance can be observed. Moreover counterfeits are nowadays often a combination of fake and genuine parts that have been manipulated. Authenticating each part of the product is important in the frame of the investigation to understand how the counterfeiters proceed, and which prevention measures should be taken. Lab instruments like spectrometers can help confirm counterfeits of packaging for packaging components on which visually, no difference with a reference would be observed. In this study several analytical tools were evaluated to help support the authentication of the primary and secondary packaging of one medicinal product as an example using seven reference materials and five counterfeits. In some cases, visual examination of the packaging already enabled to detect counterfeits of the studied features. Also the boxes, leaflets and vials have been analysed with Infrared (IR) spectroscopy, Raman microspectroscopy, X-ray fluorescence (XRF) spectroscopy, Scanning Electron Microscopy (SEM) and microcomputed tomography (microCT). According to the obtained results, IR and XRF could support the visual examination of the different packaging components. Despite the small amount of counterfeits, relevant links could also be detected between the studied cases based on the packaging characteristics.

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Heavy metals in haze episode will continue to threaten the quality of public health around the world. In order to decrease the emission of heavy metals produced from coal burning, an online X-ray fluorescence (XRF) analyzer system, consisting of an XRF analyzer with data acquisition software and a laser rangefinder, was developed to carry out the measurement of heavy metals in pulverized coal. The XRF analyzer was mounted on a sled, which can effectively smooth the surface of pulverized coal and reduce the impact of surface roughness during online measurement. The laser rangefinder was mounted over the sled for measuring the distance between a pulverized coal sample and the analyzer. Several heavy metals and other elements in pulverized coal were online measured by the XRF analyzer directly above a conveyor belt. The limits of detection for Hg, Pb, Cr, Ti, Fe, and Ca by the analyzer were 44 ± 2, 34 ± 2, 17 ± 3, 41 ± 4, 19 ± 3, and 65 ± 2 mg·kg(-1), respectively. The relative standard deviation (%RSD) for the elements mentioned was less than 7.74%. By comparison with the results by inductively-coupled plasma mass spectrometry (ICP-MS), relative deviation (%D) of the online XRF analyzer was less than 10% for Cr, Ti, and Ca, in the range of 0.8-24.26% for Fe, and greater than 20% for Hg and Pb.

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Cultural heritage objects have a major contribution to the historical patrimony of every country. In Romania, wooden churches are famous, they are mostly dated in between the XVth and XXth century, but unfortunately many of them have been destroyed, by natural or anthropic means. Therefore, the necessity of conservation and restoration has appeared, to the ones that still exist, as legacy for the future generations. In the present article, an Imperial Gate from a wooden church in Cluj County, Romania, has been investigated, using scientific techniques (FTIR and XRF). A 3D reconstruction has been performed, using similar colors with the original artwork, as resulted from the scientific investigation of the painting materials. A limited number of constituent materials have been used for this artwork, and the wood species used was lime, due to the ease of carving.

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The use of a portable X-ray fluorescence spectrometer (PXRF) equipped with a miniaturised X-ray tube producing a small 8 mm diameter X-ray beam required the validation of two new sampling protocols for the immediate screening of occupational lead exposure. First, lead in dust and fumes, collected by Institute of Occupational Medicine (IOM) inhalable samplers on 25 mm diameter membrane filters, is quantified using PXRF. To account for irregular dust deposition, the filters are rotated manually by quarter turns. Multiple PXRF readings are collected from the central region and from two locations in the outer region. The inner region is distinguishable from the outer region, but the two outer region locations are indistinguishable. High correlations (R(2) > 0.99) are found between the PXRF results and historical results obtained using a reference method based on a laboratory wavelength-dispersive sequential XRF instrument (WDXRF) for lead loadings between 1-161 µg. The PXRF results from the outer regions of the filters show a bias of -13% with respect to the WDXRF. Once this bias is allowed for, 95% of all PXRF results lie within -28% and +38% of the WDXRF results. Neither instrument accounts for potential dust accumulation on the walls of the IOM sampler. Therefore, methods based on their use can only be considered semi-quantitative. Second, a protocol combining direct PXRF measurements on workplace surfaces with surface wipes is designed for immediate on-site quantification of removable surface lead residues. The quantification of such residues by this method is compared with subsequent off-site wet chemistry analysis of the surface wipes. The two methods show a good correlation (R(2) ∼ 0.88). The ratio of the amount of removable residues determined by PXRF and wipe sampling is close to one with range 0.26-3.94. It is demonstrated that PXRF can be used as an effective tool for the immediate screening of occupational lead exposure. Although this article focused on lead, PXRF can identify simultaneously a number of other metals.

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