Microstructure and phase composition of bronze Montefortino helmets discovered Mediterranean seabed to explain an unusual corrosion

Two Monterfortino helmets, recovered in the Mediterranean seabed, show unusual features with respect to the more common helmets of the same period and found in underwater environments. Hence, they were investigated by a multi-analytical approach, which allowed us to identify the compounds constituting the helmets and to make some considerations about their metallurgy, although all the metal was converted to degradation products. The helmets, originally made in bronze, have maintained their original shape because of copper sulphides formation. The observed differences in composition between the two helmets were attributed to the position modification, of one of them, into the seabed along centuries. For the first time, a microstructural investigation permits to reconstruct the history of the aging processes involved in the total oxidation of roman bronze helmet metal

New Insight on Archaeological Metal Finds, Nails and Lead Sheathings of the Punic Ship from Battle of the Egadi Islands

: The wreck of the Punic ship exhibited at the Archaeological Park of Lilybaeum (Marsala, Italy) is a unique example in the world. In this paper, the investigation of some metal finds (30 nails and 3 fragments of sheathings) belonging to the wreck of the Punic ship is reported. Portable X-ray fluorescence and Raman spectroscopy allowed us to identify the elements and compounds constituting them and make some deductions about their composition. X-ray diffractometry, polarised optical microscopy and scanning electron microscopy of the collected micro-samples allowed us to explain the degradation that occurred in the underwater environment

Influence of the Ce :YAG amount on structure and optical properties of Ce :YAG-PMMA composites for white LED

Ce:YAG-poly(methyl methacrylate) (PMMA) composites were prepared by using a melt compounding method, adding several amounts of Ce:YAG in the range 0.1–5wt.%. The optical properties of the obtained composites and of the composites combined with a blue LED were measured to investigate the effect of the amount of Ce:YAG on the resulting emitted light in view of possible application in white LED manufacture. An increase in Ce:YAG amount caused an increase in the emission and a shift of 15 nm, influencing the white LED performance. The structure and morphology of the composites were studied. The results show that the interaction between the two components, observed by using solid state NMR experiments, are the responsible for the observed shift.The authors acknowledge the University of Palermo, FFR 2012–2013 –ATE 0594 and CORI201

Effect of halloysite nanotubes filler on polydopamine properties

Hypothesis: Polydopamine (PDA) is widely used as hydrophilic coating for several applications. However, most of the methods studied to improve or manipulate PDA properties are multistep and time-consuming, and there is a need for versatile strategies aimed at controlling and modifying the properties of PDA. Experiments: PDA-halloysite nanocomposites were produced under different oxidation conditions in alkaline and acidic media and were characterized by UV–visible and attenuated total refraction- Fourier Transform Infrared spectroscopies, thermogravimetric analysis, porosimetry, scanning electron microscopy, X-ray diffraction and contact angle measurements against the reference PDA polymer. Findings: Inclusion of the inorganic halloysite nanofiller in the PDA component was found to affect the thermal properties of the nanocomposite as well as its structure, depending on the experimental conditions. The ability of the nanocomposites to adsorb organic dyes as possible membrane coatings for environmental remediation was also investigated by different models, suggesting promising applications as adsorbents for the treatment of wastewaters

Knowledge, attitudes and practices towards COVID-19 among nursing students of the University of Palermo: results from an online survey

Introduction: The aim of the study was to evaluate the knowledge, attitude and practices towards SARS-CoV-2 among nursing students of University of Palermo during the rapid rise period of the COVID-19 pandemic. Materials and methods: This is cross-sectional study. A survey was provided to all nursing students and consisted of two parts: demographics and Knowledge, Attitude and Practices (KAP) survey. A multivariate linear regression model was used and adjusted Odds Ratios (aOR) are presented. Results: 575 students were interviewed, and their mean age was 22.29 ± 4.2. The overall score indicates good knowledge (p=0.046) and good practices among the four courses of study (p=0.038). Multivariate linear regression showed that Attitude score (b = -0.29; p = 0.024) and Knowledge score (b = 0.10; p = 0.026) adjusted for age, gender, year of study, perceived economic status, perceived health status were significantly associated with Practice score. Conclusion: Our results suggest that proper health education is useful for encouraging optimistic attitudes and maintaining safe practices among future category of nurses

First discovery of orichalcum ingots from the remains of a 6th century BC shipwreck near Gela (Sicily) seabed

Ingots recently recovered from the seabed near Gela, a major harbour of Sicily, reveal an unexpected side of ancient metallurgy. The ingots were found near remains of a ship and earthenware dated around the end of the VI century BC and probably coming from the eastern Mediterranean and the Aegean sea. The ingots were analysed by means of X-Ray Fluorescence spectroscopy via a portable spectrometer. Results indicate that they are mostly consist of copper and zinc although many of them have a significant amount of lead. This alloy is nowday called brass, but in ancient time it was know as orichalcum, one of the rarest and most precious alloy along with gold and silver. Only small items of orichalcum dating before Christ were found so far. The visual examination corroborate by evaluation of dimensions and weight, are consistent with the dating hypothesis and reveals important information about the casting production. The discovery of more than twenty-two kilos of ingots is extraordinary: a first ray of light upon a forgotten technology, which involved also smelter plants (maybe more than one), a commercial network, and a number of end users, who certainly appreciated the properties of shining orichalcum: ductility, mechanical strength, durability, and value

Interaction of ZIF-8 with Cu2+ in water solutions for remediation applications

Water pollution is a global environmental problem and now more topical than ever. Among several pollutants, heavy metals are of particular interest due to their toxicity and high bioaccumulation capacity. Metal-organic frameworks (MOFs) are exceptional adsorbents for capturing metal ions in water. Between them, ZIF-8 has high sequestration capacity of copper ions in water, but the capture mechanism remains unclear. The scope of this work is to investigate the interaction of ZIF-8 with copper ions in aqueous solution at pH=7, discriminating between effects due to water, copper and those resulting from their concomitant presence. Several samples were prepared dispersing a certain amount of ZIF-8 in an aqueous Cu2+ solution at a fixed concentration in the range between 0-300 mg/L. X-ray diffraction, Raman Spectroscopy, gas porosimetry, Thermogravimetry, X-ray photoelectron spectroscopy (XPS) and Electron Paramagnetic Resonance (EPR) were used to evaluate the structural features of the ZIF-8 before and after Cu2+ capture. Our results indicates that ZIF-8 is capable to capture high amounts of Cu2+, but in aqueous solution it undergoes a dissolution and reorganization process that affect its applications in simply powder form

Gli affreschi provenienti dalle terme romane di Reggio Calabria. Dalla conoscenza al restauro

The frescoes at marine thermae discovered in 1886 during the excavation of the small thermal complex dating between the 1th and 3rd century AD, and located on the seafront of Reggio Calabria, have been collected already collapsed. They are currently part of the permanent exhibition of the National Archaeological Museum of Reggio Calabria. This paper illustrates the results of the restoration intervention, carried out in the form of an educational activity in the context of an agreement signed between the MarRC and the University of Calabria, and the results of the diagnostic investigations carried out by the IPCF-CNR of Messina and the STEBICEF department of the University of Palermo

Physicochemical Characterization Of Ancient Paper And Parchment With Solid State Nuclear Magnetic Resonance

Historical paper and parchment are widely investigated in order to comprehend mechanisms of degradation and to plan proper conservation interventions. NMR spectroscopy is a powerful tool that allows to the changes occurring during the degradation process and to get information on the state of conservation. In this work a Cross Polarization Magic Angle Spinning Nuclear Magnetic Resonance (13C{1H} CP MAS NMR) study of a 16th century book is reported. The physicochemical characterization of paper samples collected from the book was performed through the evaluation of intensity and the changes in line width of signals in the spectra. 13C{1H} CP MAS NMR spectra of paper samples collected from the book, allowed us to obtain information on its state of conservation. Information on the extent of oxidative and hydrolysis degradation have been achieved through the evaluation of the crystalline/amorphous ratio, the presence of emicellulose, the presence of cellulose oligomers and of non-cellulosic compounds such as lignine or organic additives. This technique also provided information on the state of degradation of two parchment samples collected from the cover of the book