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Environmental monitoring in Northern Italy, one of the most polluted areas in Europe, is of paramount importance. Leaf monitoring throughout magnetic and scanning electron microscopy (SEM–EDS) analysis could be considered a good complementary analysis to sampling stations, but the lack of evergreen plants in the northern Italy towns may hinder magnetic leaf analysis in the winter season. Therefore, we tested three species of urban vegetation, which are evergreen and commonly found in urban environment, namely Hedera helix L., Parietaria officinalis L. and Rubus caesius L. Magnetic susceptibility, chosen as a simple parameter suitable for monitoring, was measured in seven stations, during the period 25 January 2019 to 8 March 2019 at a weekly step, in the cities of Torino and Parma in the same days. P. officinalis and R. caesius showed the best response, but also H. helix was suitable to detect highly polluted areas. In Torino, the magnetic susceptibility decreased in the last sampling, together with PM10, whereas in Parma it increased, likely for the beginning of the academic period in the University Campus. SEM–EDS analysis was done comparing leaves from the same plant sampled in February 2019, in highly polluted conditions, and in May 2020, after 2 months of very limited traffic, due to national lockdown. Silicate grains of natural minerals, sized between 10 and 20 µm, are present in both samples, whereas Fe oxides, about one micron size, possibly coming from car brake consumption, are prominent in the February 2019 sample. Magnetic susceptibility of leaves form the examined species looks promising to spot urban sites with high metal pollution.

Villa di Teodorico in Galeata (Forlì-Cesena, Emilia Romagna) is an important archeological site in the north of Italy occupied from sixth century BC to twelfth century AD. The most interesting results concern the Roman age, when a large villa was built, and the late antiquity, when the Ostrogothic king Theodoric decided to build in this area his palatium (early sixth century AD). The archeometric investigation was performed on Roman wall paintings fragments and on late antique glass sectilia fragments belonging to Palazzo di Teodorico by using a multi-technique approach that included micro-Raman spectroscopy, scanning electron microscopy with energy-dispersive spectroscopy, X-ray powder diffraction, UV–visible–NIR diffuse reflectance spectrophotometry with optic fibers and optical stereo-microscopy.. This analytical approach allowed the identification of all components, collecting molecular, elemental, microscopic, morphological and chromatic data. The characterization of samples supplied essential archeological, historical and technological information. The production techniques and the rich materials employed suggest the importance of the site in different periods. The evolution of the manufacturing technologies and the possible trade routes mainly during late antique period are witnessed by the change in the raw materials. Graphical abstract

To examine the effects of chemical composition on thermal expansion in the pyroxene mineral group, X-ray diffraction data have been collected from room temperature to ~925 °C on a chemically diverse group of 13 pyroxenes including four orthorhombic and nine monoclinic samples. Additionally, resulting unit-cell volumes computed from the XRD data have proven to be good tests for a large number of thermal expansion models; the physical model by Kroll and coworkers and the empirical one by Fei have been found to be especially useful. Modeling also has allowed the connection of present data, collected at temperatures above 25 °C, to the volume data of other workers for much lower temperatures, well below 0 °C, and also extrapolation of values for volume and thermal expansion well beyond the measurement range.We have found for orthopyroxenes that Fe2+-Mg2+ substitution has little effect on thermal expansion coefficients for volume. For clinopyroxenes, however, greater thermal expansion occurs in Ca2+-(diopside, augite, hedenbergite, johannsenite) than in Li+-(spodumene) or Na+-bearing members (jadeite, aegirine, kosmochlor). Present data support the observation that differences in volume thermal expansion relate primarily to differences in expansion along the b crystallographic axis. This apparently is due to the greater concentration of M1 polyhedra along the b crystallographic axis, where expansion differences can be related to the shared O1-O1 polyhedral edge and inter-oxygen repulsion that is made easier by divalent, as opposed to trivalent, cation occupancy of the M1 crystallographic site.

Chrysotile, one of the six regulated asbestos minerals, is the most employed and commercialized one for industrial applications, thanks to its outstanding technological properties. As of today, asbestos is banned in more than sixty countries worldwide, but the mining and use of chrysotile is still permitted in many other countries. Carcinogenic to humans, asbestos is currently deeply examined in toxicological research aimed at understanding the complex multistep process of asbestos-related carcinogenesis. In the toxicity and pathogenicity of asbestos fibres, the biopersistence plays a key role. In addition, the release of toxic trace metals from the crystal structure during the dissolution of the fibres in the lungs is strictly related to the surface reactivity of the fibres and to the prompt ROS formation, inducing an acute cytotoxicity. Although chrysotile is characterized by a relatively low biodurability, adverse effects with early carcinogenic signs are to be considered.In the characterization of chrysotile asbestos and its intergrown mineralogical species, micro-Raman spectroscopy is an effective tool for the identification of asbestos fibres and impurities even at trace level, whose occurrence is under the detection limit of other analytical techniques. An extensive micro-Raman characterization was carried out on chrysotile from different mining locations - i.e. the abandoned mine of Balangero (Turin, Italy) and the active Orenburg Minerals mine near Yasniy (Russia). In addition to the identification of the chrysotile structure, impurities of other fibrous or lamellar species consisting of balangeroite and antigorite were easily recognized by their characteristic Raman spectra. Within the fibres, traces of Cr as toxic metal were confirmed by the characteristic photoluminescence peaks of Cr3+ emissions, located at about 680 nm. Furthermore, micro-Raman investigations, combined with SEM-EDS analyses, enables the identification of micrometric crystals – even of a few microns - of several Fe compounds, whose eventual dissolution in the organic environment should be carefully considered. Besides magnetite (Fe3O4) as the most abundant Fe compound, other Fe oxides and oxyhydroxides were identified, including hematite (α-Fe2O3), lepidocrocite (γ-FeOOH) and akageneite (β-FeOOH). Further Fe-bearing compounds include Fe sulphides, also containing Ni as toxic metal. Mackinawite (FeIIS) was detected by micro-Raman analysis in both nanocrystalline and partially oxidized forms, suggesting the presence of both Fe(II) and Fe(III) species. Nanocrystalline mackinawite is characterized by an intense sharp peak at ~280 cm-1 and a weak contribution at ~204 cm-1, whereas partially oxidized one is distinguished by Raman modes at ~122, 168, 253, 309, 323 and ~355-360 cm-1. Unlike Fe oxides, whose solubility in the organic environment in typically scarce, the rapid dissolution of Fe sulphides - such as mackinawite - may exhibit the so-called “Trojan-horse effect”, contributing to the acute toxicity of chrysotile. The presence of these micro-crystals should be considered in the release of metals in the reactivity of chrysotile fibres in the lungs. Micro-Raman spectroscopy was successfully proven as a quick and reliable technique to identify inorganic micro-crystals dispersed in chrysotile fibres.

PCDD/Fs (polychlorinated dibenzo-p-dioxins/dibenzofurans) and PCBs (polychlorinated biphenyls) are ubiquitous persistent pollutants with reduced bioavailability, which bioremediation using soil fauna is still managed to treat. This research set out to: (i) study the suitability of earthworms (Eisenia fetida), alone and associated with plants (Lepidium sativum), for the decontamination of PCDD/F and PCB polluted soils in Brescia-Caffaro (Italy), at total and congener concentration levels; (ii) simulate the action of earthworms in groundwater contamination process and nutrient mobility. Five treatments were set up: (i) uncontaminated soil with E. fetida (NC); (ii) contaminated soil (C); (iii) contaminated soil with E. fetida (CEf); (iv) contaminated soil with L. sativum (CLs); (v) contaminated soil with E. fetida and L. sativum (CEfLs). PCBs and PCDD/Fs in the soil prior to testing were measured. Analysis was repeated in soil treatments and percolating water at the end of the test period (4 months). Dissolved nutrient concentrations were measured in percolated water. PCB and PCDD/F concentrations, initially 259333.33 ± 10867.89 ng/kg and 176 ± 10.69 ngTE/kg, were significantly reduced after 4 months in all treatments. Treatments did not differ in total PCBs concentration (from 160,000 ng/kg to 194,000 ng/kg), but CEfLs congeners concentrations were less environmentally threatening; CEf and CLs resulted in lower PCDD/Fs concentration (79.43 ± 3.34 ngTE/kg and 73.03 ± 4.09 ngTE/kg, respectively). The action of earthworms could enhance contaminants and soluble reactive phosphorous content in percolating water.

The Raman spectra of the end member pyroxenes CaZnSi2O6 and Zn2Si2O6 are calculated by quantum mechanical modeling and compared with the experimental ones measured in synthetic (CaxZn1−x)ZnSi2O6 pyroxenes with x = 0, 0.2, 0.3, 0.5, 0.7, 1. The calculated spectra correctly predict the intensity and peak positions of the spectra recorded on the end members. The model provides also useful hints for the mode assignment at the intermediate compositions. The experimental peak positions are compared in (CaxM2+1−x)M2+Si2O6 pyroxenes, with M2+ = Mg, Co, Zn, Fe2+. These pyroxenes share a common charge and different mass and ionic radius; the relative contributions of the mass and ionic radius in the experimental spectrum are discussed in four of the most intense peaks. We found that the positions of the strongest peaks are related to the average bond distances of the polyhedra which most affect a given mode. Ca–Zn pyroxenes provide an exception, whereas the CaZnSi2O6 end member fits quite well in the bond-distance/peak positions relations found in other pyroxenes, and the same does not occur as Zn exchanges for Ca. Peak broadening occurs in Zn pyroxenes in intermediate compositions; it is related to the presence of polyhedral local configurations around Zn and Ca atoms in the M2 polyhedron. The broadening is higher in the ~ 1010 cm−1 peak (ν19), which, among the strongest peaks, shows the highest difference in the Raman wavenumber between end members. The different behaviours of Zn pyroxenes with respect to Mg, Co, and Fe2+ ones are likely related to the partially covalent bonding in the M2 cavity shown by Zn pyroxenes.

The speciation of potentially toxic elements (PTE) in bottom ashes from municipal solid waste incineration (MSWI) and their relationship with grain size is investigated. The proposed enrichment of several potential toxic elements in lower sized grains is discussed, comparing the literature and new data on Parma’s waste incinerator. Results from X-ray fluorescence spectrometry (XRF), SEM-EDS, and XRD analyses on different grain size show (1) a positive Si-trend, correlated with grain size and few lithophile elements, such as Zr and Rb. In Parma, Al, K, Mg, and Fe also correlate with Si for the portion below 2 mm, (2) a Ca-trend, with a strong negative correlation with Si and a positive correlation with loss on ignition (LOI), S, Cl, Ti, Zn, Pb, and Sn. Mineralogical composition shows a little change in grain size, as in previous investigations, but with substantial differences in amorphous content. SEM-EDS analysis shows that the amorphous portion is highly heterogeneous, with portions coming from melting during incineration, residual glass, and unburnt loss on ignition (LOI). The above results show that PTE elements are either present as metals (such as Cu and Ni, or Zn, Pb and Sn) in carbonate, sulfate, and amorphous residual LOI portions.

Several glass mosaic tesserae were found during the archeological excavations at the Villa di Teodorico in Galeata (Forlì-Cesena, Emilia Romagna, Italy), dated to early sixth century AD. This work reports the results of an archeometrical investigation realized through a multi-technique approach on 16 tesserae. The aims of the study were the determination of the glass composition, the characterization of coloring and opacifying agents, and the definition of the technological processes involved. The glass matrix and the dispersed crystallites were characterized in detail through micro-Raman spectroscopy, field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy, and X-ray powder diffraction analyses. Micro-Raman spectroscopy was proven to be very effective in the analysis of complex objects, providing information on the structure and composition of the glass and on the nature of the opacifying agents and the crystalline colorants. UV-visible-NIR diffuse reflectance spectrophotometry with optic fibers was helpful to identify the metal ions used as chromophores. The different hues were obtained by means of dispersed ions as well as crystalline compounds and metal nanoparticles. A large variety of opacifying agents was detected. Results were compared with data of contemporary mosaics within the same geographical area.

In this work, both PM10 filters and leaves have been collected, on a daily basis, over a period of five months and compared systematically. Filters were taken from an air-quality monitoring station and leaves from two Tilia cordata trees, both located near the railway station of Parma. SEM-EDS analysis on the surface and across the leaves shows that magnetic particles are almost entirely made of magnetite, and that they are found invariably on the leaves surface. The saturation isothermal magnetic remanence (SIRM) shows that for both filters and leaves the magnetic fraction mainly consists of a low coercivity, magnetite-like phase. The magnetic signals of filter and leaves and atmospheric PM concentrations are compared. The correlation is better for filters, mostly with parameters related to vehicular pollution, and improved for both filters and leaves once data were averaged on a 10 days basis. Filters and leaves equally show an increase in magnetic signal during the fall-winter period together with PM10 content. The comparison between leaves and filters shows that: 1) leaves give a qualitative picture, and in our case they could be used as environmental proxies after averaging the results over multiple days; 2) the correlation with PM10 is weaker, indicating that there is a PM10 contribution from non-magnetic particles, like calcite and clay minerals, pollen and spores; 3) multidomain particles contribution from filters indicates a strong relation with vehicular polluters, suggesting the important role of larger particles; 4) magnetization from leaves and filters are weakly related, due to the different sampling lapse.

Cobalt-based pigments were synthesized using clinopyroxene as crystalline host. The pigments are a Ca(Co x Mg 1- x )Si 2 O 6 solid solution, with x = 0.05, 0.2, 0.4, 0.5, 0.6, 0.8 Co apfu , and were synthesized from melt. The pigments were characterized by single-crystal X-ray diffraction, SEM-EDS, optical microscopy, colorimetry and optical spectroscopy. The pigments were then tested in glazes and glassy coatings for ceramic tiles to determine their colouring performance. The synthesized pigments showed a pink colour with different shades, due to the absorption of Co 2+ in octahedral coordination. The colour disappeared in the Ca(Co 0.05 Mg 0.95 )Si 2 O 6 pigment after grinding. The Ca(Co x Mg 1- x )Si 2 O 6 pigments partially dissolved in glazes, acting like dyes, and bestowed a blue shade on coatings, with a colour efficiency similar to industrially used blue colorants (cobalt aluminate spinel and cobalt olivine). In the glassy coatings, pigment dissolution occurred at a lower extent, and a colour intermediate between the pyroxenes and the pigment-bearing glazes was obtained. The Co content in pyroxene dyes is lower than conventional pigments, being down to 5%wt.

A P21/c synthetic (Ca0.2Co0.8)CoSi2O6 pyroxene was synthesized by slow cooling from melt at high pressure. Single crystals suitable for X-ray diffraction were obtained and refined. The results were compared to those of C2/c pyroxenes along the series CaCoSi2O6–Co2Si2O6. Strong similarities in the crystal chemical mechanism of the transition with the synthetic CaFeSi2O6–Fe2Si2O6 and CaMgSi2O6–Mg2Si2O6 pyroxenes, both at an average and local level are apparent.The results, examined together with two new refinements of pigeonite in the ureilites ALHA77257 and RKPA80239 and with a set of natural and synthetic C2/c and P21/c pyroxenes, show that the average cation radius in the M2 site is the driving force for the phase transition from C2/c to P21/c. The longest M2–O3 distances and the O3–O3–O3 angles follow the same trend, dictated only by the ionic radius in M2, in either synthetic or natural pyroxenes, regardless of the ionic radius of the M1 cations. The transition also affects the difference between bridging and non-bridging oxygen atoms and the extent of tetrahedral deformation, whereas the M1–O, M2–O1 and M2–O2 distances are unaffected by the transition and are determined only by the ionic radius of the bonding cation. The structural changes between the ionic radius and the high temperature C2/c and P21/c transitions are similar, and different to the high-pressure transition.Analysis of natural and synthetic pyroxenes shows that the transition with composition occurs in strain free pyroxenes for a critical radius of 0.85 Å. Increasing strain stabilizes the P21/c structure to a higher temperature and larger cation radius.Finally, our results show that the monoclinic P21/c Ca-poor clinopyroxene, i.e the mineral pigeonite, crystallizes only at conditions where the structure is HT-C2/c, and changes to the P21/c symmetry during cooling.

A bronze statue, coming from a judicial seizure and representing a satyr (Silenus), was examined to determine its provenience and the historical period of production. The iconological aspects, colours, patina and conservation state are strictly compatible with ancient bronze production in Imperial Roman age but a doubt on the authenticity was cast by the presence of nineteenth and twentieth century copies of original Herculaneum statues produced by Chiurazzi smelter. Analyses by optical microscope, XRD and SEM–EDS have been performed to characterize the samples collected from the surface of the statuette, a little piece of alloy and the casting core. The right arm of the statuette was broken and in the internal part, some charred tissues were present, allowing to perform a 14 C-AMS dating. Three possible dating has been assigned, but not before the 1640 ± 30 AD. Strong corrosion features like a well-formed and stratified patina were present, suggesting a long lasting alteration and indicating that patina's investigation cannot be the only criteria for authentication in this case. Gypsum in the casting core and a ternary alloy in the bronze, like the one used in the Chiurazzi forgery have been found. The origin from Vesuvius area is confirmed by the finding of minerals present in subsilicic alkalinic volcanic environment.

Melanophlogite (type I clathrate) has a microporous framework of corner sharing SiO4 tetrahedra, which can host guest gases. Here, a multi–analytical approach has been employed to understand the phase transitions with temperature and the degassing behaviour of a melanophlogite sample, which contains CO2 together with minor CH4 amount as enclathrated molecules.Synchrotron powder diffraction data collected between 110 and 380 K (ESRF, ID22 beamline) show a clear splitting of the major peaks up to about 360 K. Le Bail analysis shows that the low temperature phase is monoclinic, changing to cubic at ∼370 K. Landau theory analysis indicates that the transition is second order, with Tc = 369(1) K. Moreover, significant volume strain related to the phase transitions accounts for the lower thermal expansion at higher temperature. Differential scanning calorimetry shows evidence of a further phase transition between 220 and 250 K. The transition is confirmed by powder diffraction, with a change in slope in the b unit cell parameter and in volume expansion in the same temperature range. High temperature X-Ray powder diffraction between 313 and 673 K shows that thermal expansion decreases with temperature, possibly in relation with a structural rearrangement within the cubic structure during degassing. Thermogravimetric analysis shows that degassing of the guest gases begins at 450 K, and occurs at a higher rate above 750 K, but it is not completed even at T = 1273 K. Melanophlogite confirms to be a good host carrier for the gases, with gas loss only at higher temperature. Moreover, as degassing occurs with almost no thermal expansion, it could open promising application for its mechanical stability during degassing.

Dating and authenticating stone-sculpted works of art is a challenging aspect of cultural heritage studies. In fact, it is often possible to provenance the rock, by comparison of petrological, mineralogical and geochemical data, but no dating of the sculpture can be obtained. Also, stylistic observations need to be considered with care. However, in the case of mastic incrustation sculptures, the applied polychromy can support dating studies, based on pigments and binders. In the church of Saint-Germain-en-Laye, a haut-relief representing the Deposition from the Cross is exposed. The calcareous slab is decorated with red and black mastics. It resembles closely the Deposition from the Cross in the transept of Parma Cathedral, dated 1178 and “signed” by Benedictus Antelami. However, the St-Germain Deposition appeared in 1994, when it was donated to the parish by the descendants of Julien Auguste Duperrier, marble worker and collector of Italian antiquities. His last trip to Italy took place in 1924. No information is available on his deal, neither on the transport means arranged, nor on the sculpture itself (author, contractor, date, etc.). Art historical and historical considerations propose either a 12th or 19th–20th c. context for the creation of the sculpture. Chemical analyses of the pigments and binders are therefore proposed to clarify the dating the work of art. Microscopic samples are characterized by a multi-analytical approach: vibrational spectroscopies and X-ray powder diffraction are used to characterize the rock and the polychrome mastic. The rock is identified as a micritic limestone, and shows sulphation issues. Through Raman scattering measurements, the pigments were identified: carbon in the black mastic, and a mixture of red lead and a modern synthetic pigment (PR49:1) in the red areas. This information sheds new light on the chronology and manufacture of the Deposition from the Cross of Saint-Germain-en-Laye. These results allow for a better definition of further lines of research, and to finally propose an authorship for the sculpture.

We report on the preparation of a novel hierarchically-porous super-activated carbon originating from organic waste with specific surface area exceeding 3000 m2/g, obtained starting from biochar derived by the pyrolysis of poultry litter. The chemical activation process proved to be efficient to remove the majority of impurities other than carbon, stabilizing a highly porous hierarchical structure with local graphene-like morphology. The presence of P and S with concentration below 0.1 wt% distinguishes this activated carbon from the usual ones obtained from vegetal sources. Thanks to these features, the obtained porous compound demonstrated to behave as an excellent electrode material for high-performance symmetric supercapacitors, reaching high specific capacitance up to 229 (13) F/g. Remarkably, the devices also supply high current density of 10 A/g without using any conducting additives and display high power density and reliability. Moreover, these optimal performances have been obtained operating by using simple eco-friendly electrolytes, like KOH and Na2SO4 aqueous solutions. The availability, the biocompatibility and the inexpensiveness of the starting materials, together with the low environmental impact of the electrolyte, suggest possible large-scale applications for such devices, for example in the field of transportation or in renewable energy-grids, but also in the field of bio-medicine.

After cellulose, lignin is the most abundant plant-derived polymer in nature. It provides mechanical support to plants, but it has also a defense role against pests and diseases, thanks to antioxidant, bactericidal, and antifungal properties, deriving from its polyphenolic nature. Huge quantities of technical lignins are obtained during several industrial processes and they actually represent a waste of paper pulp and bioethanol industry. Although in the last decades many efforts have been directed to obtain lignin valorization in several fields and for diverse applications, this biobased polymer is still largely underutilized. In particular, very little is known about the possibility to exploit its antioxidant, antifungal, and antibacterial properties in the agronomical field. On the other hand, pest control is often achieved by using copper-based pesticides, but environmental and health issues urge for novel solutions implying reduced copper content. We here describe novel hybrid organic-inorganic materials obtained by combining copper(II) salts with two types of technical lignins. Cu-containing materials (lignin@Cu) have been characterized by different techniques, including X-ray powder diffraction and transmission electron spectroscopy analyses, revealing nanocrystals of brochantite (Cu4SO4(OH)(6)) grown in the lignin matrix. Lignin@Cu was tested for its antifungal and antibacterial profile against a vast panel of pathogens of agronomical interest. Furthermore, preliminary tests on crops in a greenhouse were performed: lignin@Cu had better performances than a commercial pesticide based on copper(II) hydroxide on tomato plants against Rhizoctonia solani, indicating a great potential of these materials as plant protection products.

A laboratory investigation evaluates the potential of using stabilized fly ash from municipal solid waste incinerators (MSWIs) as a filler in asphalt mixtures. Nine asphalt mixtures compose...

We report a detailed study on the magnetic properties of the pyroxene series M2M1Si

The pyroxene structure was successfully used as a crystalline host for a new Co-based pink pigment. Different compositions of Ca1-xCo1+xSi2O6 (0 2O6 end-member. For increasing cobalt content, an assemblage of Co-olivine, Co-åkermanite and Ca,Co-pyroxene was found. Samples containing Co-åkermanite have a deep blue color stemming from Co2+ in tetrahedral coordination, while those with Co-olivine are violet due to Co2+ in octahedral coordination. The best conditions for the synthesis of a CaCoSi2O6 single phase were then investigated, finding that a proper annealing cycle at 1150 °C prevents the formation of metastable Co-åkermanite. The CaCoSi2O6 pyroxene was tested as a ceramic pigment into glazes and glassy coatings. In most cases, it behaves like a dye, completely dissolving in the melted glaze, analogously to Co-olivine.

The Raman spectra of Ge-clinopyroxenes CaM2+Ge2O6 (M2+ = Mg, Mn, Fe, Co, Ni, Zn), general formula M2M1T2O6, are reported for the first time. Their spectral features are discussed in comparison with corresponding Si-pyroxenes. The vibrational wavenumbers of germanates may be roughly obtained by a scale factor of about ~0.8 by those of the corresponding silicates, due to the Ge-Si mass difference. The main peaks in the germanate Raman spectra at ~850 and ~540 cm−1 may be related to Ge-O tetrahedral stretching and chain bending, respectively; minor peaks between 200 and 400 cm−1 are ascribed to bending and stretching of the non-tetrahedral cations. Within Ge-pyroxenes, possible correlations between crystallographic parameters and the vibrational wavenumbers are investigated. The main stretching mode at ~850 cm−1 shows wavenumber changes with M2+ substitutions, but no simple correlation can be found with M2+ cation mass or size. On the other hand, the chain bending wavenumber linearly decreases with increasing ionic radius of the M2+ cation: the expansion of the M1 polyhedron reduces the chain kinking angle and the Ge-Ge distances correspondingly increase. Copyright © 2015 John Wiley & Sons, Ltd.

Serpentinites are rocks, often used in buildings, formed in large extent by minerals of the serpentine group: chrysotile, antigorite, lizardite, and polygonal serpentine. The fibrous type (e.g. chrysotile) of serpentine group minerals, along with several amphibole varieties (e.g. actinolite and tremolite), are the major components of asbestos family. The exposure to fine fibrous asbestos powder is linked to diseases such as pleural mesothelioma and asbestosis. The identification of the main varieties of the serpentine group, laminated or fibrous, becomes an issue of great interest for public health. This work introduces an analytical strategy able to distinguish the different serpentine polymorphs directly on the sample, allowing the analysis within their textural environment, evidencing at the micrometer scale the mineral reactions of the phases. Samples coming from the Koniambo massif (Grande Terre Island, New Caledonia) were studied by means of optical microscopy, scanning electron microscopy–energy dispersive X-ray spectroscopy, and Raman spectroscopy. Raman peaks observed in the high wavenumber spectral range of 3550–3850 cm−1, associated with OH stretching vibrations, allow the discrimination of the all four serpentine varieties. The relationship between the different varieties of serpentine, at a micrometric scale, in complex samples, has been investigated by two-dimensional Raman mapping. Copyright © 2015 John Wiley & Sons, Ltd.

Albite is one of the most common minerals in the Earth's crust, and its polymorphs can be found in rocks with different cooling histories. The characteristic spectrum of vibration of the albite mineral reflects its structural Si/Al ordering. In this study, we report on the comparison between the Raman spectra measured on a natural and fully ordered (as deduced on the basis of single-crystal X-ray diffraction data) ‘low albite’, NaAlSi3O8, and those calculated at the hybrid Hartree–Fock/density functional theory level by employing the WC1LYP Hamiltonian, which has proven to give excellent agreement between calculated and experimentally measured vibrational wavenumbers in silicate minerals. All the 39 expected Ag modes are identified in the Raman spectra, and their wavenumbers and intensities, in different scattering configurations, correspond well to the calculated ones. The average absolute discrepancy is ~3.4 cm−1, being the maximum discrepancy |Δv|max ~ 10.3 cm−1. The very good quality of the WC1LYP results allows for reliable assignments of the Raman features to specific patterns of atomic vibrational motion. Copyright © 2015 John Wiley & Sons, Ltd.

During their production, management, and landfilling, bottom (BA) and fly (FA) ashes from municipal solid waste incineration may liberate Fe-bearing, ultrafine particles and easily enter different environmental sinks of the biosphere. We aim to explore a collection of BA and FA samples from Italian incinerators to probe magnetic mineralogy and the fraction of harmful superparamagnetic (SP) nanoparticles (d < 30 nm). X-ray diffraction, electron microscopy observation, temperature-and frequency-dependent magnetometry, and Mossbauer analysis are performed. The integration of information fromour rockmagnetic and non-magnetic techniques leads us to conclude that the dominant magnetic carrier in our samples is magnetite and its intermediate/impure forms, while sulphides (i.e., monoclinic pyrrhotite) are important ancillary magnetic phases. The SP fraction fluxing from the BA and FA outputs of a single incinerator is detected and estimated in 10(3) tons/year. This work stresses the need to calibrate the current technologies towards a safermanagement of combustion ashes and certainly to inform the environmental impact assessment by using a combination of different methods. (C) 2017 Elsevier B.V. All rights reserved.

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The effect of the substitution of Ca with Co, on the phase transition and on the extension of the miscibility gap, was studied to model the general mechanism of phase transitions and solid solutions in (Ca,M 2+ )M 2+ Si 2 O 6 pyroxenes. Eleven pyroxenes with composition Ca 1−x Co 1+x Si 2 O 6 , (0 ≤ × ≤ 1) were therefore synthesized by piston cylinder at P = 3 GPa, and T between 1100 and 1350 °C. The samples were characterized by SEM-EDS, XRD powder diffraction, and TEM. The results were compared with those of Ca-Fe and Ca-Mg pyroxenes. The phase diagram of Ca-Co pyroxenes is similar to that of Ca-Fe and Ca-Mg ones, with a wide asymmetric miscibility gap, and higher solubility in the Ca-rich side of the gap. The solubility on the Ca-rich side of the gap is related to the radius of the cation substituting. The cell parameters of the Ca-Co pyroxenes undergo a sudden change at the composition of about 0.4 Ca apfu, due to the C 2/ c – P 2 1 / c phase transition. The change in volume with composition follows an ideal trend, in the C 2/ c phase, dictated by the ionic size of the substituting cation. Deviation from the C 2/ c behavior are instead observed in the P 2 1 / c field and ascribed to volume strain. The same turnover was found in Ca-Mg, Ca-Fe, and Ca-Mn pyroxenes. The C 2/ c – P 2 1 / c transition occurs with decreasing the M2 average cation radius, down to a critical value between 0.85 and 0.88 A, depending on the series. A stabilization of the C 2/ c phase related to crystal field in Ca-Fe and Ca-Co pyroxenes is suggested by the analysis of the volume strain in the P 2 1 / c field. A key finding is that a miscibility gap may develop either by lattice strain related to cation substitution, within a series where all end-members have the same structure, or for the combined effect of lattice strain and a phase transition, as is the case for pyroxenes.

Single-crystal X-ray data collection was performedin situatT= 300 and 700°C on a sample synthesized along the jadeite–hedenbergite series. The structural data, together with those of a previous investigation of a crystal of the same composition, were compared to those of the endmembers. The evolution of the displacement parameters with temperature shows significant residuals for the O1, O2 and O3 oxygen atT= 0 K, most significantly in the O1, which were interpreted as an indication of positional disorder.Volume thermal expansion and axial deformation ellipsoids were calculated for the above sample together with those of a series ofC2/cpyroxenes. Pyroxenes with a divalent M2 cation, Ca, Fe and Mg have a greater expansion than those with a monovalent M2, like Na and Li; the Na pyroxene endmembers with Al, Cr and Fe were observed to show greater expansion than corresponding Li ones.The greater axial expansion is found along thebaxis, except in LiCrSi2O6; the changes along thebaxis are related to the volume thermal expansion. The axial orientation and anisotropy of the two axes onto the (010) plane is different in Na, Li and Ca-Mg-Fe pyroxenes, but the overall expansion onto the (010) plane, given by the sum of the scalar expansion along the two axes on (010), is very similar in pyroxenes.The deformation along thebaxis with temperature and composition is driven by the deformation along b of the octahedral M1 chain; most important is the contribution from the O1−O1 shared edge between M1 octahedra in the same octahedral chain.

Bottom (BA) and Fly Ashes (FA) from Municipal Solid Waste Incineration (MSWI) represent huge amounts of solid by-products that still pose environmental and health problems. Some routes for MSWI ashes management/reuse have been proposed (e.g., inertization, landfilling, reuse as filler, geopolymers), but not all of BA and FA hazardous components are fully understood. Precise identification of minerals from BA and FA is challenging due to several factors: high number of phases, MSWI combustion temperature, and variable chemical composition of feedstock materials. In addition, (trans)formation of magnetic iron oxides, which have been correlated with heavy metals pollution and the presence of toxic ultrafine superparamagnetic (SP) grains in a range of materials, occurs during incineration and quenching. We have undertaken the study of BA and FA samples from Italian MSWI plants by combining magnetic and mineralogical analysis for probing mineralogy and the extent of SP grains. The BA and FA samples are characterized by narrow hysteresis curves and low coercivity (Bc, 7.2 – 14.1 mT), suggesting significant reversible component of magnetization. Also, the analysis of thermomagnetic properties shows that both BA and FA gain magnetization during cooling. The Low temperature remanent curves by Magnetic Properties Measurement System (MPMS) show magnetite-like shapes for most of samples, but the Vervey transition in FA samples is not clear probably due to the presence of oxidized/impure magnetite or unblocking of SP grains. Measurements of AC susceptibility by MPMS might support the fact of a significant contribution of SP grains in FA (FA show larger frequency dependence than BA). We performed XRD analysis on FA and BA samples, including different magnetic extracts of BA in order to shed some light on iron oxides phases. The main mineralogical phases found in BA are quartz, calcite-vaterite, melilite group minerals and plagioclase; FA contain Ca-aluminosilicates and more sulphates and chlorides with respect to the BA. Iron oxides such as wurstite, hematite, and the magnetic spinel-type iron oxides are noted both in BA and FA. The XRD pattern on BA magnetic extracts confirms that magnetite or impure spinel-type iron oxides (e.g., Mg-magnetite, Ti-magnetite, and maghemite) are in charge of their strong magnetic response. However, on the basis of previously obtained chemical analysis, the presence of impure magnetite containing Cr, Zn, Mn, and Cu cannot be ruled out neither in BA nor in FA. Rietveld refinement to assess the extent of minor metals substitution is ongoing. These preliminary observations emphasise the metastable nature of MSWI ashes and might lead to a better assessment of the environmental impact related to iron oxides.

A reappraisal of crystal structure, optical properties and technological behaviour of black spinels in the Co—Cr—Fe—Mn system was carried out to define the best compositions and disclose the role of crystal chemistry in colouring performance and pigment-glaze interactions. Twenty ternary and quaternary spinel formulations were designed using crystallochemical criteria and prepared by simulating the industrial synthesis. Powder samples were characterized through X-ray diffraction (Rietveld), optical, Raman and Mossbauer spectroscopies, and technological testing in several glazes and glassy coatings. Black spinels fall in a relatively narrow field of unit cell and inversion parameters in between “chromites” and “magnetites”. Their cation distribution is governed by Co2+ occupancy of tetrahedrally-coordinated site T and Cr3+ occupancy of octahedrally-coordinated site M, with Mn3+ hosted at M, while Mn2+ and Fe3+ are distributed over both sites. Nevertheless, Raman and Mossbauer spectra indicate a growing disorder in cation partitioning going towards the iron-rich terms. The pigment technological behaviour depends to a large extent on crystal chemistry of spinels, with no effect by grain or crystallite size. The best colouring performance corresponds to recommended compositions able to withstand corrosion and change in crystal chemistry in contact with melted glaze. Three different pathways can give rise to excellent black pigments: (a) strongly disordered spinels having an inversion parameter i∼0.2; (b) moderately disordered spinels, free of Mn3+, with i

The pressure dependence of the Raman spectrum of low albite, NaAlSi3O8, has been investigated from 0.0001 to 10.4 GPa, at room temperature, on a single crystal compressed hydrostatically in a diamond anvil cell. The Raman vibrational features move to higher wavenumbers υ i with increasing pressure, due to the decrease in the unit-cell volume corresponding to a drastic shrinkage of the framework. The slopes Δυ i/ΔP of the four investigated bending modes (i.e. at 478, 507, 578 and 815 cm−1, at 0.0001 GPa) show evident changes at ~6.5 and ~8.5 GPa. This behaviour may be ascribed, in the absence of phase transitions, to the evolution of the compressional mechanisms at the atomic scale found in previous high-pressure studies on albite (mainly by X-ray diffraction), through a model based on tilts of rigid tetrahedra. The Raman data of this study allowed also to bracket the pressure range in which the occurrence of the first change in the compressional behaviour was found by X-ray diffraction.

The Raman spectrum of diopside has been calculated by using three purely Density Functional Theory (DFT) Hamiltonians (PBE, WCPBE, LDA), the Hartree-Fock Hamiltonian (HF) and three hybrid HF/DFT ones (B3LYP, WC1LYP, PBE0). A comparison has been done between the calculated frequencies with those measured by Raman spectroscopy on a natural sample, along with several different orientations and beam polarizations, or retrieved from literature; such a comparison demonstrated the excellent performances of the hybrid Hamiltonians in reproducing the vibrational spectrum of the mineral, in line with what it is generally observed in literature concerning other mineral phases. In particular, the mean average absolute discrepancies of the calculated frequencies with respect to the experimental data were: 3.2 (WC1LYP), 4.7 (B3LYP), 6.5 (PBE0), 18.0 (PBE), 9.7 (WCPBE), 7.3 (LDA), and 40.6 cm −1 (HF). The very good quality of the WC1LYP results allowed for a reliable assignment of all of the experimentally observed Raman signals, and the corresponding assignments to specific patterns of atomic vibrational motion (normal modes).

The effect of Zn substitution on a series of clinopyroxenes along the join CaZnSi2O6-Zn2Si2O6 was studied. The pyroxenes were synthesized at P = 4-5 GPa and T = 1000-1200 degrees C by a multi-anvil apparatus. SEM-EDS and XRD analysis showed complete solid solution; all of the samples have the C2/c space group. No miscibility gap between clino- and orthopyroxene nor phase transition to the P2(1)/c space group was found. Moreover, the cell volume of Ca-Zn pyroxenes decreases less than expected from the decrease of the average cation size for the substitution of Zn for Ca. The crystal structures of three synthetic pyroxenes of composition (Ca0.5Zn0.5)ZnSi2O6, (Ca0.3Zn0.7) ZnSi2O6, and (Ca0.2Zn0.8)ZnSi2O6 were refined by single-crystal X-ray diffraction (R-4 sigma between 3 and 4.5%). It was observed that the Ca-Zn substitution occurs in the M2 polyhedron, with a sub-site splitting of Zn in a position at approximately 0.7 angstrom from Ca. In this position, Zn retains a highly distorted fourfold coordination; moreover, the tetrahedral chain configuration is little changed along the series, and the MI polyhedral size increases with Zn substitution in M2. An implication of the present work is the interpretation of the partitioning of Zn between clino-pyroxene and melt. The distribution coefficients of Zn and Co are quite different in rocks of the same composition, despite their very similar ionic radius, and the difference is related to the preference of Zn for the M2 site, where Zn may find a suitable atomic coordination.

Single-crystal X-ray data collection was performed in situ at T = 300 and 700°C on a sample synthesized along the jadeite–hedenbergite series. The structural data, together with those of a previous investigation of a crystal of the same composition, were compared to those of the endmembers. The evolution of the displacement parameters with temperature shows significant residuals for the O1, O2 and O3 oxygen at T = 0 K, most significantly in the O1, which were interpreted as an indication of positional disorder. Volume thermal expansion and axial deformation ellipsoids were calculated for the above sample together with those of a series of C2/c pyroxenes. Pyroxenes with a divalent M2 cation, Ca, Fe and Mg have a greater expansion than those with a monovalent M2, like Na and Li; the Na pyroxene endmembers with Al, Cr and Fe were observed to show greater expansion than corresponding Li ones. The greater axial expansion is found along the b axis, except in LiCrSi2O6; the changes along the b axis are related to the volume thermal expansion. The axial orientation and anisotropy of the two axes onto the (010) plane is different in Na, Li and Ca-Mg-Fe pyroxenes, but the overall expansion onto the (010) plane, given by the sum of the scalar expansion along the two axes on (010), is very similar in pyroxenes. The deformation along the b axis with temperature and composition is driven by the deformation along b of the octahedral M1 chain; most important is the contribution from the O1−O1 shared edge between M1 octahedra in the same octahedral chain.

A 7-year-old dog was presented with a history of an open lesion on the right thoracic wall, discharging honey-like fluid and small stones. Ultrasonography and computed tomographic fistulography identified a cholecystocutaneous fistula; cholecystectomy was curative. Veterinarians should consider this disease in patients with long-term discharging lesions on the right thoracic or abdominal wall.

The crystal structure of three C 2/ c clinopyroxenes with composition (Ca0.8Co0.2)CoSi2O6, (Ca0.6Co0.4)CoSi2O6 and (Ca0.4Co0.6)CoSi2O6 was refined down to R4σ = 2.6% by single-crystal X-ray diffraction. The crystals were synthesized at P = 3 GPa by cooling from 1500 to 1200 °C in a piston-cylinder apparatus. At the end of the refinement cycles, electron density residuals (up to 2.1 e−) were observed close to the M2 site and related to the site splitting of Ca and Co in the M2 polyhedron in the two subsites M2 and M2′. Split refinement significantly improved the agreement factor and decreased the uncertainty in the atomic coordinates. Similar features were found in (Ca,Mg)MgSi2O6 and (Ca,Fe)FeSi2O6 intermediate pyroxenes. The average structural changes related to the cation substitution at the M2 site in (Ca,Co)CoSi2O6, (Ca,Mg)MgSi2O6, and (Ca,Fe)FeSi2O6 pyroxenes are similar: the T tetrahedron becomes more regular, the difference between M1-O bond lengths increases, and the M2-O3 bond lengths with the furthermost O3 oxygen atoms become longer. The changes in the M2-O bond distances are, however, not linear, and they are higher for more increased substitution. The largest structural deformation occurs on the (010) plane, with higher deformation at about 60° from the c axis for any composition. The orientation of the deformation ellipsoid is most related to a shift in tetrahedral chains. The scalar deformation for the cation substitution, ɛs, is linearly related to the cation radius of the average M2 site (IRM2), i.e., the deformation is higher as the cation size decreases, following the equation: ɛs = −0.0072(12)IRM2 + 0.0082(13), R2 = 0.75. Increasing deformation with cation substitution is supported as the major limiting factor for solid solution. The displacement parameters for unsplit M2, O2, and O3 atoms increase up to the intermediate composition, indicating a local configuration for the M2 polyhedron centered by Ca and Co. However no significant change in U eq of the O3 atom is observed up to 20% substitution of the smaller cation in the M2 site. Comparison with Raman spectral data suggests that local chain structural configurations occur only for the substitution of the smaller cation in the M2 site higher than 20%, and that the substitution mechanism is different for C 2/ c clinopyroxenes with lower and higher Ca content.

The Raman spectra of eight clinopyroxenes synthesized along the join diopside-clinoenstatite (Di-Cen, CaMgSi2O6-Mg2Si2O6) were measured. The splitting of the 670 cm−1 mode of the Ag symmetry, observed in the composition Di52En48 to clinoenstatite, was interpreted as evidence of a C 2/ c-P 21/ c phase transition. The transition was also revealed by deviation from the linear dependence of the peak position vs. composition and by the appearance of several new peaks in the samples richer in clinoenstatite. Analysis of peak positions vs. structural changes suggests that for the M2 polyhedron, in which Ca substitution for Mg occurs, a different deformation mechanism acts in Ca richer and poorer P 21/ c pyroxenes, and that Ca richer P 21/ c pyroxenes deform with the same mechanism as C 2/ c pyroxenes. The frequency of the peak at 670 cm−1 was found to change linearly with the kinking angle of the tetrahedral chains for C 2/ c and of the B chain for P 21/ c , whereas the position of the peak ascribed to the A chain was little affected by the kinking angle. Peak broadening in C 2/ c Ca-rich homogeneous pyroxenes was interpreted to be a consequence of the positional disorder of the Ca and Mg in the M2 cavity: peak broadening increases with increasing Mg content for peaks assigned to M2-O vibrations, but it changes little for peaks assigned to chain bending, which suggests that cation substitution in the M2 cavity occurs with little interaction with the silicate chain. Furthermore peak broadening was observed in intermediate pyroxenes as a consequence of mottled textures, antiphase domains, and compositional inhomogeneity.

Estudos têm evidenciado a importância de uma comunicação mais aberta, com mais qualidade e diminuição da assimetria na relação médico-paciente. Entende-se que a comunicação médico-paciente é de tal importância que interfere, não apenas na satisfação e no entendimento do paciente, mas também na adesão ao tratamento.Nesse sentido, as Diretrizes Curriculares Nacionais do Curso de Graduação em Medicina apontam a necessidade de o aluno aprender a comunicar-se adequadamente com os colegas de trabalho, os pacientes e seus familiares, informando-os e educando-os por meio de técnicas apropriadas. Instrumentos como o Objective Structured Clinical Examination (OSCE), o Clinical Performance Examination (CPE) e o Patient-practitioner orientation scale (PPOS), vêm sendo utilizados para avaliar habilidades clínicas e atitudes do médico e do estudante. Opresente trabalho apresenta o resultado de um processo de elaboração e validação de um novo instrumento, o Questionário do Comportamento Comunicativo do Médico (QCCM), com base no Teacher Communication Behavior Questionnaire (TCBQ), para analisar a percepção de pacientes do comportamento comunicativo do médico. Trata-se de um estudo exploratório do qual foram sujeitos 106 pacientes cadastrados no Ambulatório de Endocrinologia do Anexo Hospital Borges da Costa,Hospital das Clínicas da Universidade Federal de Minas Gerais (HC-UFMG), bem como os 10 médicos auxiliares desse centro de atendimento. Na elaboração do novo instrumento, com foco específico na área médica, foram consideradas as características desejáveis no médico para um processo comunicativo eficiente. Na validação externa, identificou-se uma possível associação entre escala PPOS e QCCM, ficando comprovadas, estatisticamente, evidências de associação entre a atitude do médico em relação ao paciente e a percepção do paciente do comportamento comunicativo do médico. Na validação interna do QCCM, as escalas do questionário apresentaram confiabilidade satisfatória, exceto a escala Controle. Os valores dos índices para cada escala analisada indicaram uma percepção positiva do paciente em relação à comunicação do médico, no contexto do estudo. Os médicos perceberam seu comportamento comunicativo de uma forma maispositiva do que seus próprios pacientes. Quando considerado o gênero do médico, pacientes homens apresentaram uma percepção mais positiva das médicas do que dos médicos em relação à escala Controle; e pacientes mulheres perceberam as médicas mais compreensivas e amigáveis que os médicos. Considerando aescolaridade, pacientes com nível superior tiveram uma percepção mais positiva dos médicos em relação à escala Controle. Considerando a presença de sintomas depressivos, pacientes sem depressão tiveram uma percepção mais positiva em relação ao encorajamento e elogio de seus médicos. Por fim, considerando o tempo do médico no Ambulatório de Endocrinologia, pacientes tiveram uma percepçãomenos positiva do controle de médicos com mais de 20 anos de trabalho no serviço. Ajustes no QCCM são necessários, mas certamente, esse instrumento poderá contribuir na reflexão da prática médica, na melhoria da comunicação e como instrumento auxiliador em programas de humanização na relação médico-paciente. Estudos futuros poderão melhor definir os fatores relacionados à percepção dopaciente do comportamento comunicativo do médico. Studies have been highlighting the importance of an opened communication, with more quality and reduction of asymmetry inside the doctor-patient relationship. The doctor-patient communication is so important that affects not only the patients satisfaction and understanding, but the adhesion to the treatment as well. Regardingthis topic, the Diretrizes Curriculares Nacionais do Curso de Graduação em Medicina indicates the need of the student to learn how to communicate properly with colleagues, patients and relatives, informing and educating through the appropriate techniques. Instruments like the Objective Structured Clinical Examination (OSCE), the Clinical Performance Examination (CPE) and the Patient-Practitioner OrientationScale (PPOS) have been used to evaluate clinical skills and doctor and medical student´s attitudes. This study presents the result of the elaboration process and validation of a new instrument, the Doctor Communication Behavior Questionnaire (DCBQ-QCCM), based on the Teacher Communication Behavior Questionnaire (TCBQ), to analyze the patients perception of the doctor´s communication behavior. It is an exploratory study that surveyed 106 patients registered at the Ambulatório de Endocrinologia of Anexo Hospital Borges da Costa, Hospital das Clínicas of Universidade Federal de Minas Gerais (HC-UFMG), as well as 10 adjutant doctors of this clinic. Through the development of the new instrument (QCCM), with a specific focus on the medical field, it was considered the desirable doctor´s profile for an efficient communication process. In the external validation, a possible association has been identified between PPOS scale and QCCM, therefore proving, statistically,evidences of an association between the doctor´s attitude towards the patient and the patients perception of doctor´s communication behavior. During the internal validation of QCCM, the instruments scales showed a satisfactory liability, except from the Controlling scale. The values of the scores of every analyzed scale indicate a positive perception of the doctor communication, in the context of this study. The doctors perception of their communication behavior was more positive than their ownpatients perception. When considered the doctors gender, male patients showed a more positive perception about Controlling scale of female doctors than male doctors; and female patients perceived female doctors more understanding and friendly than male doctors. Considering the patients schooling, patients with a high education level had more positive perception about Controlling scale. Considering the existenceof depressive symptoms, patients without depression had more positive perception about encouragement and praise of their doctors. Lastly, considering doctors time at the endocrinology clinic, patients had less positive perception about controlling of doctors with more than 20 years of work at the clinic. Some adjustments in the QCCM are required, but certainly, this instrument can contribute to the reflection on the medical practice and communication improvement as well as serve as anauxiliary instrument in humanization programs for the doctor-patient relationship. Futures studies can better define the factors related to patients perception of the doctor´s communication behavior.