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In the natural ecosystem, fungal entomopathogens are the most efficient biocontrol agents against insect pests. In this study we offer an alternative for conventional fungal diagnostic, Surface-enhanced Raman spectroscopy (SERS) technique combine with principal component analysis (PCA) for detection and identification three entomopathogenic fungi, namely, IBCB 66 Beauveria bassiana, IBCB 130 Isaria fumosorosea, and IBCB 425 Metarhizium anisopliae. Using a simple preparation approach, highly active silver nanoparticles suitable for detecting complex biomolecules were produced for application in the SERS technique. Entomopathogens fungi produced highly enhanced and reproducible Raman signals based on their biochemical composition due to the high density of hot spots at the confluence of silver nano-aggregates, allowing the three entomopathogens species to be differentiated in the SERS spectrum fingerprint region, 550-1700 cm-1. The SERS method, along with PCA analysis, accounted for over 99 % of total variance and allowed for very high probability discrimination between the three entomopathogens, allowing taxonomic affiliation to be determined in a short period of time. These findings suggest that the SERS methodology can be used to develop a new, fast, accurate, and cost-effective diagnostic method for fungal entomopathogens.

“Retirantes”, “Criança Morta” e “Enterro na Rede” são três pinturas a óleo, pintadas em 1944 pelo reconhecido artista brasileiro Candido Portinari. As três pinturas representam cenas da miséria gerada pelas migrações durante as secas no nordeste brasileiro. As três pinturas entraram para a coleção do museu como um conjunto em 1948. Devido às diferentes historias materiais e restaurações passadas, as pinturas apresentavam distintos estados de conservação. Foi organizado um projeto interdisciplinar com curadores, conservadores e cientistas, com o fim de estudar e restaurar cada uma das pinturas. A imagiologia e a caracterização material foram essenciais para justificar o tratamento proposto, que se realizou com a intenção de estabilizar as alterações presentes e recuperar a homogeneidade estética das três pinturas, permitindo uma exposição coerente do conjunto novamente.

A non-destructive standard-free analytical method of obtaining stable isotope ratios in materials using nuclear reactions excited by an 11.75 MeV proton beam is demonstrated for a special 63Cu/65Cu target characterized traceably by Rutherford backscattering spectrometry (using 2.2 MeV protons). The method is general and is capable of being a useful alternative to standard ICP-MS methods. Relatively high energy proton beams are required to excite multiple isotopes of most elements of interest, and the many resulting nuclear reaction products are filtered by coincidence methods to characterize the desired isotope ratios. Specifically: the use of particle–gamma coincidences permits identification of specific channels populated in the nuclear reaction and avoids or minimizes typical drawbacks of this method including high backgrounds and interfering reactions. The test Cu target was a sandwich of a natural Cu and an enriched 65Cu foil, and particle–gamma coincidences were measured for the reactions 63Cu(p,πγ){63Cu,60Ni} and the corresponding reactions for 65Cu (where “π” represents the energetic charged particle reaction product: proton or alpha). Limitations of the method, and applications in cultural heritage and other fields are discussed.

Ion Beam Analysis (IBA) comprises a set of analytical techniques suited for material analysis, many of which are rather closely related. Self-consistent analysis of several IBA techniques takes advantage of this close relationship to combine different Ion Beam measurements in a unique model to obtain an improved characterization of the sample. This approach provides a powerful tool to obtain an unequivocal and reliable model of the sample, increasing confidence and reducing ambiguities. Taking advantage of the recognized reliability and quality of the simulations provided by SIMNRA, we developed a multi-process program for a self-consistent analysis based on SIMNRA calculations. MultiSIMNRA uses computational algorithms to minimize an objective function running multiple instances of SIMNRA. With four different optimization algorithms, the code can handle sample and setup parameters (including correlations and constraints), to find the set of parameters that best fits simultaneously all experimental data., Comment: 27 pages, 5 figures, research paper

Penicillium piscarium can be indicated as promising in the treatment of sites contaminated with uranium. Thus, this research aimed to analyze the P. piscarium dead biomass in uranium biosorption. This fungus was previously isolated from a highly contaminated uranium mine located in Brazil. Biosorption tests were carried out at pH 3.5 and 5.5 in solutions contaminated with concentrations of 1 to 100 mg/L of uranium nitrate. Our results showed that the dead biomass of P. piscarium was able to remove between 93.2 and 97.5% uranium from solutions at pH 3.5, at the end of the experiment, the pH of the solution increased to values above 5.6. Regarding the experiments carried out in solutions with pH 5.5, the dead biomass of the fungus was also able to remove between 38 and 92% uranium from the solution, at the end of the experiment, the pH of the solution increased to levels above 6.5. The analysis of electron microscopy, Energy-dispersive spectroscopy, and X-ray fluorescence demonstrated the high concentration of uranium precipitated on the surface of the fungal biomass. These results were impressive and demonstrate that the dead biomass of P. piscarium can be an important alternative to conventional processes for treating water contaminated with heavy metals, and we hope that these ecofriendly, inexpensive, and effective technologies be encouraged for the safe discharge of water from industrial activities.

In this work, several attributes of the internal morphology of drupaceous fruits found in the archaeological site Monte Castelo (Rondonia, Brazil) are analyzed by means of two different imaging methods. The aim is to explore similarities and differences in the visualization and analytical properties of the images obtained via High Resolution Light Microscopy and X-ray micro-computed tomography (X-ray MicroCT) methods. Both provide data about the three-layered pericarp (exo-, meso- and endocarp) of the studied exemplars, defined by cell differentiation, vascularisation, cellular contents, presence of sclerenchyma cells and secretory cavities. However, it is possible to identify a series of differences between the information that can be obtained through each of the methods. These variations are related to the definition of contours and fine details of some characteristics, their spatial distribution, size attributes, optical properties and material preservation. The results obtained from both imaging methods are complementary, contributing to a more exhaustive morphological study of the plant remains. X-ray MicroCT in phase-contrast mode represents a suitable non-destructive analytic technique when sample preservation is required.

RESUMO Os debates sobre o pioneirismo de Hercule Florence (Nice, França, 1804 - Campinas, SP, 1879) na descoberta do processo fotográfico basearam-se, principalmente, em seus manuscritos, uma vez que poucas de suas épreuves photographiques (experiências fotográficas) sobreviveram. Os avanços tecnológicos das últimas quatro décadas permitiram que em 2016 alguns destes exemplares de impressions à la lumière solaire fossem submetidos a análises por metodologias não destrutivas no Instituto de Física da Universidade de São Paulo. Foi possível, então, ampliar o conhecimento sobre os materiais e os procedimentos utilizados em 1833 para a obtenção das primeiras fotografias das Américas, seis antes do anúncio da descoberta da técnica por Louis Daguerre, na França. ABSTRACT The debates about Hercule Florence (Nice, France, 1804 - Campinas, SP, 1879) as the pioneer in the discovery of the photographic process were based mainly on his manuscripts, since few of his épreuves photographiques (photographic experiments) survived. Technological advances in the last four decades have allowed some of his impressions à la lumière solaire to be subjected to analysis by non-destructive techniques at the Instituto de Física of the Universidade de São Paulo in 2016. It was then possible to broaden knowledge of the materials and procedures used in 1833 to obtain the first photographs of the Americas, six years before the announcement of the discovery of the technique by Louis Daguerre in France.

RESUMO Neste artigo, são apresentados os resultados dos exames arqueométricos de Física aplicada sobre duas peças de mobiliário do acervo do Museu Paulista, uma arca-cofre e uma cadeira de couro de sola feitas por volta do século XVIII. As técnicas de análise utilizadas foram o ED-XRF e o imageamento com fluorescência de luz ultravioleta. As análises interdisciplinares tiveram por objetivo identificar os materiais com os quais as peças foram compostas, evidenciando informações históricas sobre a produção moveleira na cidade de São Paulo no século XVIII e princípios do XIX. Os resultados obtidos permitiram identificar parte dos materiais usados na pintura da arca-cofre, como o branco de chumbo e o vermelhão (ou Cinabre), no couro curtido da cadeira e nas partes metálicas de ferro e latão de ambas as peças, ainda que outros procedimentos ainda necessitem ser aplicados para a obtenção de resultados sobre outros materiais. As informações obtidas com as fontes materiais foram confrontadas com dados de documentação textual mais abrangente, como listas de compras de tintas, relatos de viagem e manuais artísticos da época, de maneira a permitir a contextualização da vida material e econômica da cidade, revelando sua dinamicidade e as intrincadas redes comerciais em que estava imbricada. ABSTRACT This article presents the results of applied Physics archeometric measurements on two pieces of furniture from the Museu Paulista collection, a chest-safe and a tanned leather chair, both made around the eighteenth century. The analysis techniques used were ED-XRF and imaging with ultraviolet light fluorescence. The interdisciplinary analyses sought to identify the materials with which the pieces were composed, thus presenting historical information about furniture production in the city of São Paulo in the eighteenth century. The obtained results allowed the identification of some of the materials used in the painting of the chest-safe - white lead and vermilion (or cinnabar) - and in the tanned leather and metal parts of the chair - iron and brass in both parts -, although additional procedures still need to be applied for obtaining results on other materials. To allow the contextualization of the material and economy life of São Paulo, the information obtained from material sources were confronted with broader textual documentation data such as paint commission lists, travel reports and artistic manuals of the time, thus revealing the city’s dynamism and its intricate commercial networks.

This work concerns the archaeometric analysis of ceramic fragments from archaeological excavations carried out in “Sambaqui do Bacanga”, “Sambaqui do Panaquatira” and “Rabo de Porco”, located in the Sao Luiz city area, at Brazilian northeast. Ancient civilizations that inhabited that territory were characterized as fishing, catchers, hunters and ceramist populations. Dates obtained by thermoluminescence ranged from 6600 to 127 BP. The studied samples were sixty three representative pottery fragments selected of stratigraphic levels from the surface up to 170 cm deep for Sambaquis do Bacanga and Panaquatira and from surface up to 105 cm depth for Rabo de Porco. The three analytical methods employed were Computed Radiography, PIXE and XRF. Sixteen elements were measured with good statistics in the different ceramic samples through EDXRF and PIXE analysis: Al, Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, Rb, Sr, Y and Zr. Multivariate statistical analysis, Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA), of the fragments elemental composition were performed to separate and correlate the groups of the samples. Fragments of the three archaeological sites grouped into two clusters, the first is composed of samples from “Sambaquis do Bacanga and Panaquatira”, and the second consists of the “Rabo de Porco” samples. This result indicates that each cluster of fragments was manufactured with different clays, and “Sambaquis do Bacanga and Panaquatira” fragments are derived from the same source or same kind of clay. The internal structure of the ceramic fragments observed by Computed Radiography revealed the presence of various sizes and types of anti-plastics in the sherds.

The elemental mapping of large areas using ion beam techniques is a desired capability for several scientific communities, involved on topics ranging from geoscience to cultural heritage. Usually, the constraints for large-area mapping are not met in setups employing micro- and nano-probes implemented all over the world. A novel setup for mapping large sized samples in an external beam was recently built at the University of Sao Paulo employing a broad MeV-proton probe with sub-millimeter dimension, coupled to a high-precision large range XYZ robotic stage (60 cm range in all axis and precision of 5 μ m ensured by optical sensors). An important issue on large area mapping is how to deal with the irregularities of the sample’s surface, that may introduce artifacts in the images due to the variation of the measuring conditions. In our setup, we implemented an automatic system based on machine vision to correct the position of the sample to compensate for its surface irregularities. As an additional benefit, a 3D digital reconstruction of the scanned surface can also be obtained. Using this new and unique setup, we have produced large-area elemental maps of ceramics, stones, fossils, and other sort of samples.

This work presents the development of a portable system that allows 2D elemental mapping of large areas (maximum of 35.0 × 35.0 cm2) by XRF. A measuring head, composed of an x-ray source and a detector, is mounted on a 3-axis stage with movement reproducibility better that 0.03 mm. The final elemental map resolution of 1.4 mm was experimentally determined in the best condition of collimation, and the same experiments indicate that the resolution is fully dominated by the x-ray beam spot size. The main goal of this new setup is to perform analyses of historical, archaeological and geological objects. Because it's lightweight, our setup has the potential to be of great utility for in situ analyses, given the great difficulty and high costs transporting the artifacts from the museum to a laboratory. The importance of this instrumentation is related to the need to identify the distribution of the chemical elements in large surface areas of cultural heritage objects by a nondestructive method.

Investigations into the existence of life in other parts of the cosmos find strong parallels with studies of the origin and evolution of life on our own planet. In this way, astrobiology and paleobiology are married by their common interest in disentangling the interconnections between life and the surrounding environment. In this way, a cross-point of both sciences is paleometry, which involves a myriad of imaging and geochemical techniques, usually non-destructive, applied to the investigation of the fossil record. In the last decades, paleometry has benefited from an unprecedented technological improvement, thus solving old questions and raising new ones. This advance has been paralleled by conceptual approaches and discoveries fuelled by technological evolution in astrobiological research. In this context, we present some new data and review recent advances on the employment of paleometry to investigations on paleobiology and astrobiology in Brazil in areas such biosignatures in Ediacaran microbial mats, biogenicity tests on enigmatic Ediacaran structures, research on Ediacaran metazoan biomineralization, fossil preservation in Cretaceous insects and fish, and finally the experimental study on the decay of fish to test the effect of distinct types of sediment on soft-tissue preservation, as well as the effects of early diagenesis on fish bone preservation.

RESUMO Este artigo em duas partes (histórico e análise, seguida da parte de interpretação dos dados obtidos por técnicas analíticas) apresenta um estudo da obra Autorretrato (1919, óleo/tela, 100 x 65 cm) de Amedeo Modigliani, pertencente ao acervo do Museu de Arte Contemporânea da Universidade de São Paulo (MAC USP). Através do cotejamento entre a documentação de procedência da obra, fontes críticas de abordagem da pintura de Modigliani, com as análises técnico-científicas físico-químicas e de imageamento, foi possível reavaliá-la na articulação entre sua materialidade e sua composição, bem como lançar nova luz sobre sua recepção pela crítica dos anos 1950, quando ela chegou ao Brasil e circulou no contexto internacional por meio de publicações e exposições, já como parte de uma coleção brasileira. ABSTRACT This two-part article (history and analysis, followed by the interpretation of data obtained via analytical techniques) is a study of Amedeo Modigliani’s Self-Portrait (1919, oil/canvas, 100 x 65 cm2), which belongs to the Museu de Arte Contemporânea of the Universidade de São Paulo (MAC USP). By collating documentation on the work’s provenance, critical sources regarding Modigliani’s approach to painting, and technical-scientific (physicochemical and imaging) analyses, we were able to reassess it in light of the articulation between the work’s materiality and composition. We also managed to throw new light on the work’s critical reception in the 1950s, when it arrived in Brazil and received international exposure - at that time, already part of a Brazilian collection - by means of publications and exhibitions.

We report a proof of concept constructing an experimental setup to explore the imaging capability of a single X-ray detector, simulating a pixelated X-ray detector, to measure EDXRF (Energy Dispersive X-ray Fluorescence) and EDXRD (Energy Dispersive X-ray Diffraction) image spectra simultaneously. Combining a conventional rotating anode Cu X-ray source and assembling a single X-ray detector (Si-PIN Amptek, 139 eV at 5.98 keV) on a computer controlled XY stage, a proxy of an imaging X-ray detector was constructed for the measurement of simultaneous EDXRD and EDXRF of the same spot of a sample. The main advantages of this setup are the virtual need for sample preparation and the simultaneous XRF-XRD measurements of the same spot, enabling a combined and consistent analysis of a sample. The time consumed in an analysis using this setup is largely due to the need for acquiring multiple (several hundred) single spectra, which can be compensated, by using a variable acquisition time, depending on the count rate, exploring the high dynamic range of the X-ray emission during data acquisition. A Python code was written for offline data filtering and analysis. Using a simple geometrical model, d-spacings were calculated, and the model predictions were superimposed to the ED (Energy Dispersive) surface plots with good agreement. The instrument proved to work according to expectations and helped set the main experimental parameters for a more compact and portable setup under development.We report a proof of concept constructing an experimental setup to explore the imaging capability of a single X-ray detector, simulating a pixelated X-ray detector, to measure EDXRF (Energy Dispersive X-ray Fluorescence) and EDXRD (Energy Dispersive X-ray Diffraction) image spectra simultaneously. Combining a conventional rotating anode Cu X-ray source and assembling a single X-ray detector (Si-PIN Amptek, 139 eV at 5.98 keV) on a computer controlled XY stage, a proxy of an imaging X-ray detector was constructed for the measurement of simultaneous EDXRD and EDXRF of the same spot of a sample. The main advantages of this setup are the virtual need for sample preparation and the simultaneous XRF-XRD measurements of the same spot, enabling a combined and consistent analysis of a sample. The time consumed in an analysis using this setup is largely due to the need for acquiring multiple (several hundred) single spectra, which can be compensated, by using a variable acquisition time, depending on the count rate...

Particle induced gamma-ray emission (PIGE) is an ion beam technique used for isotopic elemental analysis of materials, based on gamma-ray spectroscopy. In the traditional PIGE setup, the gamma-ray detector is positioned at the neutral angles 55° or 125° with respect to the beam direction in order to measure gamma-rays with different angular distributions. Although these angles permit measurements without an a-priori knowledge of the specific angular distributions, this choice is not efficient if one wants to identify a specific element since a longer acquisition time is needed. In this work, we propose to optimize the PIGE measurements by choosing the detector angle position due to the previous knowledge of the gamma-ray multipolarity and the nuclear reaction. We present the angular distribution calculations for the isotopes most frequently identified by PIGE analysis, specially in Cultural Heritage objects. Calculations demonstrate that a gain in the intensity up to 70% can be achieved allowing the elemental identification in shorter times. This result is promising and represents a more efficient alternative to perform PIGE measurements.

Iron has an important role in blood as an indicator of a great number of anomalies. Anemia due to iron-deficiency in the world is a public health problem in all ages and socioeconomic levels. Nowadays, Brazil’s pharmaceutical companies are testing iron compounds to reduce the costs of those new drugs. In this study, Energy Dispersive X-Ray Fluorescence Technique was applied to determine Fe concentrations in blood samples of different mice strains using a Portable XRF Spectrometer. These data may help researchers choose the convenient mice strain that best meets its medical investigation, reducing costs and optimizing their researches.

This study focuses on the results of the technical analyses performed in the copper painting “Venus with Mars and cupids”, dated around 1606–1608, attributed to the Italian painter Carlo Saraceni. As this painting is the only example of this kind of refined technique at the museum and as it is one of the masterpieces of the collection, an interdisciplinary project of in-depth study was realized at MASP´s conservation studio. On the one hand, the aim was to understand the features and the making of the artwork, bringing new insights and enhancing our knowledge of Saraceni's painting technique, since little technical information has been published about the painter's work. On the other hand, it was necessary to understand the condition of the painting by means of non-destructive analyses, as several damages were compromising the conservation of the painting in the future. Complete multispectral imaging, including infrared reflectography, and X-ray fluorescence spectrometry were made in order to characterize the original materials – as the painter´s palette – and to understand the painting's creation process. Imaging and close examination allowed also to distinguish and map all the alterations presented in the painting, leading to appropriate diagnosis and treatment. This project introduced interdisciplinary approaches and decision-making into the Conservation's studio of the museum, as well as a systematic scientific examination when confronting technical and conservation issues. This paper shows also the gains of confronting different scientific examination with scientific literature in artworks study and conservation's methodologies.

In this work, we investigated through archeometry studies the mineralogical composition of pottery shards from Conjunto Villas and Sao Joao archeological sites located in the macro-region of middle Solimoes, in the State of Amazonas, Brazil. Archeometric analyses are fundamental for classification and characterization of ancient ceramics, providing relevant data that can furnish information about production processes, types of use and social meaning of these materials. The shards were studied by optical microscopy (OM), Fourier transform infrared (FTIR) spectroscopy, energy dispersive x-ray fluorescence (ED-XRF), X-ray diffraction (XRD), and scanning electron microscopy, coupled with energy-dispersive X-ray analysis (SEM-EDX). Al, Si, K, Ca, Ti and Fe (as oxides) were identified among other minority elements in the ceramic pastes, besides the presence of cauixi and caraipe (non-plastic materials), as well as possibly shells. The crystalline phases identified were quartz, hematite, kaolinite, anatase, dolomite and illite-muscovite, being that the kaolinite was found more frequently in ceramics. The results obtained in this work add important information about the analyzed artifacts, allowing a better understanding of the ancient civilizations from the Amazon region.

SIMNRA is widely adopted by the scientific community of ion beam analysis for interpretation of nuclear scattering analysis. Taking advantage of its recognized reliability and quality of the simulations, we developed a computer program that use parallel sessions of SIMNRA to perform self-consistent analysis for energy spectra of a given sample obtained using different techniques or experimental setups. In this paper, we present a result using MultiSIMNRA on self-consistent analysis for a multielemental thin film produced by magnetron sputtering. The results demonstrate the potentialities of the self-consistent analysis and its feasibility when using MultiSIMNRA., Comment: Part of special issue: The 22nd International Conference on Ion Beam Analysis (IBA 2015)

This study reports the results obtained in the analysis of waste material samples generated by the industries of phosphate fertilizers, in particular, the use of specific filters in a portable X-ray fluorescence system, a simple equipment allowing the characterization, identification and quantification of low concentrations of Th and U (ppm). The industrial byproduct is classified as a Technologically-Enhanced, Naturally-Occurring Radioactive Material - TENORM, and therefore requires monitoring for its radio-toxic activity due to the presence of radioactive thorium and uranium families. From the results obtained, it is concluded that this technique is able to determine the contents of these elements to concentrations of tens of ppm in measurements of about 300 s, and a small sample amount (∼0.1 g).

This study tests the presence of differential preservation in the Devonian Malvinokaffric fauna from the Chapada Group (Parana Basin, Brazil). Results of EDXRF, EDS, Raman Spectroscopy, and petrographic analyses show differential preservation of shells that were originally calcite as hematite and goethite fossils, while organisms with original calcium phosphate shells tend to be preserved inside phosphatic concretions. Both preservation types are commonly associated with pseudoframboids, while calcium sulfate minerals are commonly associated with hematized fossils. From this evidence, a diagenetic model for these fossils is proposed. The model includes an early diagenetic phase (characterized by anaerobic sulfate reduction and precipitation of pyrite and carbonate-fluorapatite) and a second, near-surface chemical weathering phase (characterized by the oxidation of pyrite and precipitation of iron oxyhydroxides and calcium sulfates). Acidic conditions in both phases may account for the dissolution of less stable minerals compared to calcium phosphate. It is considered that this model may assist in understanding other similarly preserved biotas, as well as enhancing understanding of the taphonomic overprint that may occur within this important and endemic Devonian biota.

External Ion Beam Analysis is a useful tool for the characterization of cultural heritage objects. During the last decade, several significant collaborations have been established between Ion Beam Analysis (IBA) scientists and art or archeology professionals, demanding in-air IBA for a variety of different cultural heritage objects. In-air Particle Induced X-ray Emission (PIXE) analyses of an oil painting by the Italian painter, Mario Sironi, from the Museum of Contemporary Art of the University of Sao Paulo (MAC-USP), were examined. This painting is particularly interesting due to paintings on both sides (oil on canvas on the front and oil on wood on the back side). PIXE analysis helped the identification of the pigment similarities on both sides of the painting, suggesting the same authorship.

Non-destructive analyses, such as EDXRF (Energy-Dispersive X-Ray Fluorescence) spectroscopy, and imaging were used to characterize easel paintings. The analyzed objects are from the collection of the Pinacoteca do Estado de Sao Paulo. EDXRF results allowed us to identify the chemical elements present in the pigments, showing the use of many Fe-based pigments, modern pigments, such as cobalt blue and cadmium yellow, as well as white pigments containing lead and zinc used by the artist in different layers. Imaging analysis was useful to identify the state of conservation, the localization of old and new restorations and also to detect and unveil the underlying drawings revealing the artist's creative processes.

This paper presents systematic studies and analysis that contributed to the identification of the forgery of a work by the artist Emiliano Augusto Cavalcanti de Albuquerque e Melo, known as Di Cavalcanti. The use of several areas of expertise such as brush stroke analysis (“pinacologia”), applied physics, and art history resulted in an accurate diagnosis for ascertaining the authenticity of the work entitled “Violeiro” (1950). For this work we used non-destructive methods such as techniques of infrared, ultraviolet, visible and tangential light imaging combined with chemical analysis of the pigments by portable X-Ray Fluorescence (XRF) and graphic gesture analysis. Each applied method of analysis produced specific information that made possible the identification of materials and techniques employed and we concluded that this work is not consistent with patterns characteristic of the artist Di Cavalcanti.

Systematic research into art and cultural heritage objects in museum collections are growing daily across the world. They are generally undertaken in partnership with archaeologists, curators, historians, conservators, and restorers. The use of scientific methods to answer specific questions about objects produced by different societies reveals the materials and technologies used in the past and gives us a better understanding of the history of migration processes, cultural characteristics, and thereby more grounded parameters for the preservation and conservation of cultural heritage. The use of non-destructive methods, such as the PIXE analysis, is very suitable in such studies because damage or alteration is avoided and the integrity of the object maintained. Such techniques gave historians and curators at the Archaeological and Ethnology Museum in São Paulo new understanding of the Chimu collection of ceramics as well as of the technical process of preventive conservation.

This work applies the X-ray MicroCT imaging technique to discuss the identification and preservation/disturbance conditions of plant remains from the Monte Castelo archaeological site, in Brazil's southwestern Amazonia. A preliminary hypothesis based on external morphological traits and the presence of typical starch grains, associates these materials to the Poaceae caryopsis. Moreover, based on their well-preserved non-charred aspect, mineralization was considered as a possible in-situ preservation process. Data from the X-ray computed microtomography (MicroCT) analysis showed that the internal anatomy of the samples corresponds to another type of fruit, described as a small drupe sharing characters with some Anacardiaceae fruits. Additionally, all studied specimens contain a number of exogenous organic and inorganic elements suggesting the action of some disturbance processes on the Monte Castelo plant material.

Accurate knowledge about the energy loss of ions in matter is essential in many problems, ranging from fundamental to applied nuclear physics. Indeed, there is a recent and increasing demand for new data on stopping cross sections measured with high accuracy and with a rigorous budget of their uncertainty sources. In the present paper we describe an accurate and traceable approach to determine the stopping cross sections in pure elemental materials---aluminum and molybdenum---for protons in the energy range of 0.9--3.6 MeV by the transmission method. The main sources of uncertainties here considered are (i) (random) the uncertainty in the peak positions and in the Gaussian fits and (ii) (systematic) the presence of thickness nonuniformity (a special procedure has been developed to correct it as far as possible). The accuracy in the final stopping cross section is $0.63%$ ($0.32%$ random and $0.54%$ systematic) for Al and $1.5%$ ($0.44%$ random and $1.4%$ systematic) for Mo, both mainly limited by the quality and homogeneity of the foils. For Al, this high accuracy represents an improvement compared to previous publications and serves as a benchmark for our procedure. For Mo, even though the uncertainty is somewhat higher, our results will help in improving the few data currently available in the energy range here considered. The data were also compared to the most commonly employed theoretical models (srim 1985, srim 2013, pstar, and casp 5.2) and Monte Carlo codes (geant 3 and geant 4). The experimental results are electronically available as supplemental material.

Made available in DSpace on 2018-11-28T01:36:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-12-21 Brazilian Council for Scientific and Technological Development Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Exceptionally well-preserved three-dimensional insects with fine details and even labile tissues are ubiquitous in the Crato Member Konservat Lagerstatte (northeastern Brazil). Here we investigate the preservational pathways which yielded such specimens. We employed high resolution techniques (EDXRF, SR-SXS, SEM, EDS, micro Raman, and PIXE) to understand their fossilisation on mineralogical and geochemical grounds. Pseudomorphs of framboidal pyrite, the dominant fossil microfabric, display size variation when comparing cuticle with inner areas or soft tissues, which we interpret as the result of the balance between ion diffusion rates and nucleation rates of pyrite through the originally decaying carcasses. Furthermore, the mineral fabrics are associated with structures that can be the remains of extracellular polymeric substances (EPS). Geochemical data also point to a concentration of Fe, Zn, and Cu in the fossils in comparison to the embedding rock. Therefore, we consider that biofilms of sulphate reducing bacteria (SRB) had a central role in insect decay and mineralisation. Therefore, we shed light on exceptional preservation of fossils by pyritisation in a Cretaceous limestone lacustrine palaeoenvironment. Univ Sao Paulo, Inst Geosci, Programa Posgrad Geoquim & Geotecton, Sao Paulo, Brazil Univ Sao Paulo, Inst Geosci, Sao Paulo, Brazil Univ Fed Sao Carlos, Programa Posgrad Ecol & Recursos Nat, Sao Carlos, SP, Brazil Fed Univ Para, Inst Geosci, Belem, Para, Brazil Univ Sao Paulo, Inst Phys, Sao Paulo, Brazil Univ Sao Paulo, Inst Chem, Dept Fundamental Chem, Sao Paulo, Brazil Brazilian Synchrotron Light Lab, Campinas, SP, Brazil Ctr Univ FEI, Dept Phys, Sao Bernardo Do Campo, Brazil Univ Estadual Paulista, Lab Technol Plasmas, Sorocaba, Brazil Univ Fed Sao Carlos, Dept Biol, Sorocaba, Brazil Univ Estadual Paulista, Lab Technol Plasmas, Sorocaba, Brazil Brazilian Council for Scientific and Technological Development: 154062/2014-6 FAPESP: 2012/18936-0 FAPESP: 2012/00202-0

Ceramics objects are the most common artifacts found during excavation of archaeological sites and often depicts cultural habits and manufacturing technologies of the culture. The determination of macroscopic and microscopic characteristics of the ceramic objects such as the ceramic porosity, addition of tempers in the clay, main chemical components and the trace elements present in the ceramic can reveal many aspects about the manufacturing processes used by the culture, its degree of development, the provenance of the raw materials and the exchange networks. Also the radiography can help to investigate the manufactured processes, the size of the tempers used and the conservation status of the artifacts. In this present work two non-destructive techniques, radiography and PIXE (Particle Induced X-ray Emission) were used to characterize one set of thirty-six pre-Hispanic ceramic pieces from the Chimu Culture conserved in the Museu de Arqueologia e Etnologia (MAE/USP). The PIXE analyses performed in the external beam setup at LAMFI (Laboratorio de Analise de Materiais por Feixes Ionicos) allowed measure the principal chemical elements such as Al, Si, K, Ti, Fe and Ca, present in this group of pieces. X-ray imagings allowed identify the manufacture processes, the granularity of the tempers used, as well as the similarity and the differences between the pieces studied.

This study is focused on the analysis of an accumulation of inorganic elements in muscles, liver and gonad of seven fish species from São Francisco River located in the Paraná state of Brazil. Concentrations of the elements were determined using the SR-TXRF technique. In the muscles of fish species, negative length dependent relationships were observed for chromium and zinc ion absorption. The obtained results showed that accumulated Cr ions values are above the limits defined in the Brazilian legislative norm on food.

The region of Toledo River, Parana, Brazil is characterized by intense anthropogenic activities. Hence, metal concentrations and physical–chemical parameters of Toledo River water were determined in order to complete an environmental evaluation catalog. Samples were collected monthly during one year period at seven different sites from the source down the river mouth, physical–chemical variables were analyzed, and major metallic ions were measured. Metal analysis was performed by using the synchrotron radiation total reflection X-ray fluorescence technique. A statistical analysis was applied to evaluate the reliability of experimental data. The analysis of obtained results have shown that a strong correlation between physical–chemical parameters existed among sites 1 and 7, suggesting that organic pollutants were mainly responsible for decreasing the Toledo River water quality.

When a multilayered material is analyzed by means of energy-dispersive X-ray fluorescence analysis, then the X-ray ratios of Kα / Kβ , or Lα / Lβ and Lα / Lγ , for an element in the multilayered material, depend on the composition and thickness of the layer in which the element is situated, and on the composition and thickness of the superimposed layer (or layers). Multilayered samples are common in archaeometry, for example, in the case of pigment layers in paintings, or in the case of gilded or silvered alloys. The latter situation is examined in detail in the present paper, with a specific reference to pre-Columbian alloys from various museums in the north of Peru.

The effect of Cr(6+) on Allium cepa root length was studied using both clean and polluted river waters. Seven series of Cr(6+)-doped polluted and non-polluted river waters were used to grow onions. Chromium concentration (Cr(6+)) of 4.2 mg L(-1)(EC(50) value), doped in clean river water caused a 50% reduction of root length, while in organically polluted samples similar root growth inhibition occurred at 12.0 mg Cr(6+) L(-1). The results suggested that there was a dislocation to higher values in toxic chromium concentration in polluted river water due to the eutrophization level of river water.

In the present work, the trivalent and hexavalent chromium phytoaccumulation by three living free floating aquatic macrophytes Salvinia auriculata, Pistia stratiotes, and Eicchornia crassipes was investigated in greenhouse. These plants were grown in hydroponic solutions supplied with non-toxic Cr3+ and Cr6+ chromium concentrations, performing six collections of nutrient media and plants in time from a batch system. The total chromium concentrations into Cr-doped hydroponic media and dry roots and aerial parts were assayed, by using the Synchrotron radiation X-ray fluorescence technique. The aquatic plant-based chromium removal data were described by using a nonstructural kinetic model, obtaining different bioaccumulation rate, ranging from 0.015 to 0.837 l mg−1 d−1. The Cr3+ removal efficiency was about 90%, 50%, and 90% for the E. crassipes, P. stratiotes, and S. auriculata, respectively; while it was rather different for Cr6+ one, with values about 50%, 70%, and 90% for the E. crassipes, P. stratiotes, and S. auriculata.

The characterization of nitridated steel samples, in special the depth profile of nitrogen, aims to help improving the quality of the surface and to increase the durability of the steel pieces. In this work we used ERDA and NRA to determinate the profile of nitrogen in different sets of stainless steel samples. An incident beam of 35 Cl of 56 MeV was used for ERDA analysis of a first set of samples. Results indicated an homogeneous distribution for most of the identified elements, with atomic nitrogen concentrations around 2% in the analyzed depth range (0.2 μm) and the presence of thin films on the surface (about 50 × 10 15 at/cm 2 ), one of C and the other of iron oxide. In a second set of samples, 4.43 MeV gamma rays produced from 15 N( H ,αγ) 12 C reaction, using an external proton beam of 1.3 MeV, were used to quantify nitrogen concentration. N concentrations of about 0.47% were obtained comparing the gamma production rate of the samples with a referenced material (Stainless steel CRM298 – 0.236% of N in mass) irradiated in the same conditions. Also PIXE analyses were done on both sets of samples in order to identify main elements in the matrix.

Triple-escape peaks can be generated when either the electron or the positron created by the pair-formation interaction inside the active volume generates a Bremsstrahlung γ-ray with enough energy to produce another pair; however, they were never observed. MCNP5 and MCNPX simulations differ greatly in the triple-escape peak intensity for photon energies around 6 MeV but agree for 14 MeV incoming photons. An empirical model was developed to check the order of magnitude of the simulated results. An experiment performed to observe the triple-escape peak yielded negative result; the upper limit for the intensity ratio between the triple- and double-escape peaks for 6.13 MeV photons in a 240 cm 3 HPGe detector is 9×10 −4 .

Recent developments in different areas have asked for pore production on the micro and nano scale in several materials. One method for pore fabrication is the irradiation with ion beams and subsequent chemical etching. Micropores have been produced in CR39 and MakrofolTM samples by irradiation with 16O beam with, approximately, 22, 31, 39, 47 MeV. Using an optical microscope and a Scanning Electron Microscope, the linear dependence of pore diameter with etching time and the pore length limited by ion range were measured. The observed pores in Makrofol are shallower than in CR39 due to its higher bulk etch rate value. The presented data for oxygen range in CR39 and Makrofol showed good agreement, considering the experimental uncertainties, with the simulated values of TRIM.

An alternate methodology based on a portable X-ray fluorescence spectrometry (PXRFS) for determination of Fe in blood was evaluated. The iron concentrations was determined in whole blood of 18 male amateur athletes (runners) using this portable XRF spectrometer and compared with a control group (54 male donors at the same age but not involved with physical activities) obtained by XRF and NAA techniques. The Fe concentration in the blood of runners is an important factor in sports medicine contributing to the performance of endurance athletes as well as for proposing new protocols of clinical evaluation.

A collaboration project between the School of Dentistry and the Institute of Physics of the University of Sao Paulo has been established to measure elemental concentrations in teeth by proton induced X-ray emission (PIXE) and heavy ion elastic recoil detection analysis (HI-ERDA) techniques. Data on trace elements in human, bovine and swine teeth, analyzed by PIXE with a 2.4 MeV proton beam, were compared and concentrations for several elements were obtained with tens of mg/g sensitivity. HI-ERDA measurements employing a 52 MeV Cl beam were done to evaluate changes in elementary concentration in dental enamel after bleaching treatment with different products in 25 bovine incisors teeth. This non-destructive technique allowed the measurements of Ca, P, O and C concentrations above the limit of 100 mg/g.

Changes of elementary concentrations in dental enamel after a bleaching treatment with different products, is presented, with special focus on the oxygen contribution. Concentrations for Ca, P, O and C and some other trace elements were obtained for enamel of bovine incisor teeth by HI-ERDA measurements using a 35 Cl incident beam and an ionization chamber. Five groups of teeth with five samples each were treated with a different bleaching agents. Each tooth had its crown sectioned in two halves, one for bleaching test and one the other used as a control. Average values of C/Ca, O/Ca, F/Ca enrichment factors were found. The comparison between bleached and non-bleached halves indicates that bleaching treatment did not affect the mineral structure when low-concentration whitening systems were used. The almost constant oxygen concentration in enamel, suggests little changes due to whitening therapy.

A computer program CLARA that calculates a correction factor for thick target PIXE analysis is described. Using CLARA, the analysis of a powdered sample diluted in a light matrix can be corrected for X-ray self-absorption and beam energy loss to use the regular thin film PIXE yields. Dilutions of powders in boric acid were simulated for two extreme cases: carbon and iron powders. In the first case, a 10% addition of carbon changed a pre-defined thick target correction factor, R i , less than 5% for all elements. On the other hand, 10% of iron changed R i to about 7% for elements with Z > 21 but showed a 50% loss for the Al content. Using the same procedure, the analysis of Marine Sediment SRM IAEA-356 diluted to 1% in boric acid showed excellent agreement with the referenced data, although compromising somewhat the detection limits.

To open new possibilities in nuclear applied physics research, mainly for the analysis of art objects in air, an external beam facility was installed at LAMFI (Laboratorio de Analise de Materiais por Feixes Ionicos) of University of Sao Paulo. PIXE measurements were made using an XR-100CR (Si-PIN) X-ray detector pointed to the sample mounted after an approximate 11 mm air path, hence with effective beam energy of 0.9 MeV. This setup was used to characterize the corrosion products of two ethnological metallic statuettes from the African collection of the Museum of Archaeology and Etnology. PIXE analysis of the corrosion free base of one statuette showed that Cu and Zn are the main components of the alloy, while Pb is present in smaller amount. The analysis of some corrosion products showed a Zn:Cu relationship higher than that of the base, evidencing selective corrosion. The main components of the other statuette were Cu and Pb, while S and Zn were found in smaller amounts.