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1.
Adv Sci (Weinh) ; : e2401124, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39205427

RESUMEN

Real-time and in-line transversal monitoring of ionizing radiation beams is a crucial task for several applications which span from medical treatments to particle accelerators in high energy physics. Here a flexible and large area device based on 2D hybrid perovskite thin films (phenylethylammonium lead bromide), fabricated onto a thin flexible polyimide substrate, able to map the transversal beam profile of high energy radiation beams is reported. The performance of this novel tool is here compared with the one offered by standard commercial large-area technology, namely radiochromic sheets. The great potential of this class of devices is demonstrated by successfully mapping in real-time a 5 MeV proton beam at fluxes between 108 and 1010 H+ s-1 cm-2, confirming the capability to operate in a radiation-harsh environment without output signal saturation issues. The versatility and scalability of here proposed detecting system are demonstrated by the development of a multipixel array able to map in real-time a 40 kVp X-ray beam spot (dose rate 8 mGy s-1). Perovskite thin film-based detectors are thus assessed as a very promising class of thin, flexible devices for real-time, in-line, large-area, conformable, reusable, transparent, and low-cost transversal beam monitoring of different ionizing radiation.

2.
Environ Sci Pollut Res Int ; 31(35): 48233-48249, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39023727

RESUMEN

The present study evaluated an integrated biomonitoring approach based on three different bioindicators: tree rings, lichens, and beetles in a complex environment (urban-industrial-forest). In Central Italy, four sampling sites were selected to assess the anthropogenic impact of cement plants taking into account (1) long-term exposure (1988-2020) through the analysis of trace elements in tree rings of Quercus pubescens; (2) medium-term exposure (2020-2021) through the analysis of trace elements in thalli (outermost portions) of the lichen Xanthoria parietina; (3) short-term exposure in spring 2021 through the bioaccumulation and evaluation of sample vitality in transplants of the lichen Evernia prunastri and a periodic survey of entomological biodiversity carried out during spring and summer 2021. Trace elements of industrial origin were found in tree rings, with different levels of accumulation between 1988 and 2020 and a maximum in 2012. Native thalli of the lichen X. parietina showed an overall low bioaccumulation of trace elements except for Cr, probably reflecting the influence of national lockdown measures. The transplants of E. prunastri showed a weak stress response in the industrial and urban sites, but not in the forest, and identified Tl and V as the main elements contributing to atmospheric contamination, with peaks at the industrial sites. Concerning the beetles, a significantly lower number of species was found at the Semonte industrial site.


Asunto(s)
Monitoreo del Ambiente , Líquenes , Líquenes/química , Animales , Italia , Escarabajos , Industrias , Materiales de Construcción
3.
Adv Sci (Weinh) ; : e2204815, 2022 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-36437046

RESUMEN

This study reports on a novel, flexible, proton beam detector based on mixed 3D-2D perovskite films deposited by solution onto thin plastic foils. The 3D-2D mixture allows to obtain micrometer-thick and highly uniform films that constitute the detector's active layer. The devices demonstrate excellent flexibility with stable electric transport properties down to a bending radius of 3.1 mm. The detector is characterized under a 5 MeV proton beam with fluxes in the range [4.5 × 105 - 1.4 × 109 ] H+ cm-2 s-1 , exhibiting a stable response to repetitive irradiation cycles with sensitivity up to (290 ± 40) nC Gy-1 mm-3 and a limit of detection down to (72±2) µGy s-1 . The detector radiation tolerance is also assessed up to a total of 1.7 × 1012 protons impinging on the beam spot area, with a maximum variation of the detector's response of 14%.

4.
Forensic Sci Int ; 336: 111327, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35635980

RESUMEN

There is a considerable interest in developing new analytical tools to fight the illicit trafficking of heritage goods and particularly of easel paintings, whose high market values attract an ever-increasing volume of criminal activities. The objective is to combat the illicit traffic of smuggled or forged paintworks and to prevent the acquisition of fakes or looted artefacts in public collections. Authentication can be addressed using various investigation techniques, such as absolute dating, materials characterization, alteration phenomena, etc.; for paintings this remains a challenging task due to the complexity of the materials (paint layers, ground, varnish, canvas, etc.) and preferable use of non-destructive methods. This paper outlines results from concerted action on detecting forged works of art within the framework of a Coordinated Research Project of the International Atomic Energy Agency (IAEA) called Enhancing Nuclear Analytical Techniques to Meet the Needs of Forensic Sciences1. One of the main objectives is to foster the use of emerging Nuclear Analytical Techniques (NAT) using particle accelerators for authentication of paintings, with potential application to other forensics domains, by highlighting their ability to determine painting authenticity and to track restorations or anachronistic clues. The various materials comprising a test painting were investigated using an array of NAT. Binder, canvas and support were directly dated by 14C using Accelerator Mass Spectrometry (14C-AMS); binder and pigments' molecular composition was determined using Secondary Ion Mass Spectrometry with MeV ions (MeV-SIMS); paint layer composition and stratigraphy were accurately determined using Ion Beam Analysis (IBA) and differential Particle-Induced X-ray Emission (PIXE); and pigment spatial distributions were mapped using full-field PIXE. High resolution Optical Photothermal Infrared Spectroscopy (O-PTIR) molecular imaging was also exploited. Obtained results are presented and discussed. It is shown that the combination of the above-mentioned techniques allowed reconstructing the history of the test painting.


Asunto(s)
Pinturas , Iones , Espectrometría de Masas , Pintura/análisis , Rayos X
5.
Forensic Sci Int ; 335: 111282, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35378337

RESUMEN

The market of falsified or sub-standard medical products is a global scale phenomenon. This issue affects a wide range of medications, including life-saving medical products. In high-income countries the most falsified products are those defined "lifestyle", which include foremost anabolic steroids and phosphodiesterase 5 inhibitors. The spread of these products in the last years has been possible also because of their online purchase, since they can be bought anonymously and without any medical supervision or prescription. Their use can pose a serious threat for public health, especially because often are manufactured without adherence to quality standards. This leads to final products containing active ingredients different from those declared, at the wrong or unknown dose and contaminated with metals, synthesis by-products and other chemical substances. In this work, we present results on characterisation of illegal pharmaceutical products and doping agents by combining different techniques: chromatography coupled to mass spectrometry for organic analysis and accelerator-based nuclear analytical techniques, such as ion beam analysis (IBA), for elemental analysis. Three IBA techniques, namely PIXE (particle induced X-ray emission), PIGE (particle induced gamma-ray emission) and EBS (elastic backscattering spectrometry) were used in external beam mode to provide an elemental characterisation of the as-is material, placed simply in front of the proton beam, thus avoiding the need of preparing them with pre-analytical steps and greatly enhancing the measurement throughput. Several elements (F, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Br and Sr) were identified in the analysed products. External beam IBA measurements provided the quantitative elemental characterisation of the illegal pharmaceutical products and doping agents under study, complementary to the organic analysis results by chromatography and mass spectrometry thus allowing a rapid (a few minutes) and non-destructive direct assessment of the material for forensic purposes. For the first time IBA results from doping products are reported and further analysis by IBA involving two different accelerator laboratories (one in Italy and one in Brazil) allowed the comparison of results obtained on the same pharmaceutical product. Starting from the results obtained in our study, the actualisation of new research plans should be evaluated, which could lay the foundation for a classification system of illegal pharmaceutical products, doping products. and other substances, based on chromatography, mass spectrometry and IBA measurements; this could allow drawing inferences about the common characteristics of these substances, e.g. provenience of bulk materials, site of production etc. With this purpose, results obtained from two samples of the same pharmaceutical product by IBA in two different accelerator laboratories (one in Italy and one in Brazil) are compared.


Asunto(s)
Oxandrolona , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Preparaciones Farmacéuticas , Citrato de Sildenafil
6.
Sci Total Environ ; 780: 146449, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34030335

RESUMEN

The quantification of the elemental concentration of ambient particulate matter is a challenging task because the observed elemental loadings are not well above the detection limit for most analytical techniques. Although non-destructive nuclear techniques are widely used for the chemical characterization of ambient aerosol, only one multi-element standard reference filter material that mimics ambient aerosol composition has become recently available in the market. To ensure accuracy, reliability and comparability of instruments performance, multiple reference materials with different elemental mass loadings are necessary. In this study, an intercomparison exercise was performed to evaluate the measurement uncertainty and instruments performance using multi-element dust standard reference samples deposited on PTFE filters. The filter samples, produced by means of dust dispersion, were tested in terms of homogeneity, reproducibility and long-term stability (≈40 months). Eight laboratories participated in the exercise. The evaluation of the results reported by the participants was performed by using two sets of reference values: a) the concentrations reported by the Expert Laboratory, b) the robust average concentrations reported by all participants. Most of the reported on the certificate of analysis elements were efficiently detected in the sample loadings prepared as representative for atmospheric samples by the Expert Laboratory. The average absolute relative difference between the reported and the reference values ranged between 0.1% (Ti) and 33.7% (Cr) (CRM-2584). The participants efficiently detected most of the elements except from the elements with atomic number lower than 16 (i.e. P, Al, Mg). The average absolute percentage difference between the participants results and the assigned value as derived by the expert laboratory was 17.5 ± 18.1% (CRM-2583; Cr, Pb excluded) and 16.7 ± 16.7% (CRM-2584; Cr, P excluded). The average "relative robust standard deviation" of the results reported by all participants was 25.1% (CRM-2583) and 22.8% (CRM-2584).

7.
Sci Adv ; 7(16)2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33863730

RESUMEN

The direct detection of 5-MeV protons by flexible organic detectors based on thin films is here demonstrated. The organic devices act as a solid-state detector, in which the energy released by the protons within the active layer of the sensor is converted into an electrical current. These sensors can quantitatively and reliably measure the dose of protons impinging on the sensor both in real time and in integration mode. This study shows how to detect and exploit the energy absorbed both by the organic semiconducting layer and by the plastic substrate, allowing to extrapolate information on the present and past irradiation of the detector. The measured sensitivity, S = (5.15 ± 0.13) pC Gy-1, and limit of detection, LOD = (30 ± 6) cGy s-1, of the here proposed detectors assess their efficacy and their potential as proton dosimeters in several fields of application, such as in medical proton therapy.

8.
Sci Total Environ ; 571: 195-205, 2016 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-27471984

RESUMEN

Although controlled procedures for the determination of carbonaceous fractions are of importance for any air quality measurements, currently no reference method for elemental carbon (EC) and organic carbon (OC) analysis is established yet in Europe. The implementation of the different thermal evolution protocols available in the literature, differing in temperature and duration of the heating ramps, affects the results and can result in a wide variation of EC and OC values. In this study three different protocols for thermal-optical-transmittance analysis of EC and OC were compared, namely He-870 (a variation of the NIOSH protocol), He-550 (a proxy of the IMPROVE protocol), and EUSAAR_2. Measurements were carried out on PM2.5 samples collected on Quartz fibre filters in three sites of different typology: urban background and urban traffic in Florence (Italy) and regional background in Livorno (Italy). The samples were analysed before and after a washing procedure to remove possible water-soluble organic compounds (WSOC), which may enhance the charring process, complicating the EC quantification. This study evidenced a very good agreement for TC measurement (at 2-3% level) and some discrepancies in EC measurement (up to 40%), as expected. WSOC and Pyrolitic Carbon (PyC) present a good correlation, independently of site typology, demonstrating that water soluble compound can be responsible of charring mechanism during the He phase.


Asunto(s)
Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Carbono/análisis , Monitoreo del Ambiente/métodos , Compuestos Orgánicos/análisis , Material Particulado/análisis , Italia , Tamaño de la Partícula
9.
J Hazard Mater ; 241-242: 82-91, 2012 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-23026448

RESUMEN

Typical of festivals in Eastern Spain, mascletàs are high-intensity pyrotechnic events where thousands of firecrackers are burnt in an intense, rapid episode that generates short-lived heavy aerosol clouds. High temporal resolution and size distribution characterisation of aerosol components were performed to evaluate the effects of the brief (<30 min) and acute exposure on the spectators present. Very high concentrations of firework specific elements, especially in the fine fraction, were reached during mascletàs, with values of about 500 µg/m(3) for K and 300 µg/m(3) for Cl. Sr, Al, Mg, Ba, Cu, Co, Zn, and Pb concentration increase factors of more than 100 (1000 for Sr and Ba) were observed in the fine fraction with respect to background levels. Crustal origin elements, like Ca, Fe, Si, Ti, also showed an important concentration rise (~10 times above background levels) but this is due to dust resuspension by pyrotechnic explosions. The crustal components are mainly in the coarse mode (>90% elemental mass), between 2 and 3 µm. Most firework related metals are concentrated in the submicrometric region (>80%) with a trimodal size distribution. This may be interesting to epidemiologists given the toxic effects that such fine, metal-rich particles can have on human health.


Asunto(s)
Contaminantes Atmosféricos/química , Exposición a Riesgos Ambientales/análisis , Sustancias Explosivas/química , Sustancias Peligrosas/análisis , Material Particulado/química , Aerosoles , Contaminantes Atmosféricos/análisis , Ciudades , Sustancias Explosivas/análisis , Tamaño de la Partícula , Material Particulado/análisis , Recreación , Humo/análisis , España
10.
Environ Pollut ; 167: 7-15, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22522313

RESUMEN

Levoglucosan was present in all samples and its concentrations showed a pronounced annual cycle with maximum levels in the cold season. The annual percentage of ratios of levoglucosan to OC ranged from 0.04 to 9.75% evidencing a major contribution of biomass burning to the aerosol OC during the winter. In the urban-background site, OC was strongly correlated with EC in winter, suggesting that the major fraction of OC was generated as primary particles along with EC. A background levoglucosan component showed that biomass burning was continuously taking place in all the investigated sites. The biomass burning contribution to the Tuscany aerosol was made up of a background component and an additional component during winter probably due to wood burning for domestic heating.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Glucosa/análogos & derivados , Material Particulado/análisis , Contaminación del Aire/estadística & datos numéricos , Biomasa , Glucosa/análisis , Incineración , Italia
11.
Environ Sci Pollut Res Int ; 18(1): 64-74, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20559746

RESUMEN

INTRODUCTION: The concentrations of trace metals, ionic species, and carbonaceous components in PM(10) (particulate matter with aerodynamic diameters smaller than 10 µm) were measured from samples collected near an industrial complex, primarily composed of cement plants, in southeastern Spain, from September 2005 to August 2006. MATERIALS AND METHODS: Positive matrix factorization and conditional probability function were applied to this data set to identify different types of sources. RESULTS: Six significant sources were identified: crustal matter, traffic, aged sea salt, industrial emissions, secondary aerosol, and sea salt. The difficulty of separating anthropogenic sources from those of natural origin is highlighted in this study; in particular, the crustal source can be connected with both natural (African outbreaks, wind resuspension) and man-made emissions, like fugitive emissions in an industrial environment.


Asunto(s)
Contaminantes Atmosféricos/análisis , Material Particulado/análisis , África , Contaminantes Atmosféricos/química , Monitoreo del Ambiente , Geografía , Industrias , Tamaño de la Partícula , Material Particulado/química , Estaciones del Año , España
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