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Abstract: Borosilicate materials are of interest for many technological applications. Whereas sol-gel techniques are well suited for the preparation of these materials, the nominal concentration of boron is often not maintained, and a considerable amount of boron is lost during the preparation procedure. In this work we deal with the synthesis of borosilicate systems in order to analyse the problem of the boron loss. Different sol-gel precursors of B2O3 were explored and organically modified silicon alcoxide were tested, in addition P2O5 co-doping was proposed. IR spectroscopy, differential Scanning Calorimetry, Thermogravimetry and ICP-OES analyses were performed. Sol-gel synthesis of SiO2-B2O3 xerogels with a high boron content (>18wt.%) was successfully obtained by employing trimethoxyboroxine and 3-aminopropyltriethoxysilane. [Copyright &y& Elsevier]

Abstract: A kinetics study on PbGeO3 solid–solid phase transition was realised by means of differential scanning calorimetry and time-resolved X-ray powder diffraction. Isothermal and non-isothermal Johnson–Mehl–Avrami equations were applied to obtain both the activation energy E a and the Avrami coefficient n. The latter parameter has been related to morphological evidences collected by scanning electron microscopy. The limits of the applied theory, i.e., the Arrhenian behaviour of the growth rate and a steady-state nucleation rate, are finally discussed in terms of recent theoretical developments. [Copyright &y& Elsevier]

An attempt to prepare Ce- and La-doped SiO2–PbO glasses for applications as scintillators was realised via aerogel route. The synthesis has been optimised in order to obtain large massive samples required for this application. The effect of Pb in the silica matrix as a co-dopant for rare-earths atoms is discussed: in particular, an increase of rare-earth solubility has been observed. Both 207Pb and 29Si magic angle spinning (MAS) NMR were used to investigate local order and connectivity. The densification of aerogels, investigated by means of DSC, TGA, and X-ray powder diffraction (XRPD), led to glass–ceramic samples because concurrent crystallisation occurred. [Copyright &y& Elsevier]

Abstract: The aim of this research was to investigate a tough polymer to develop 3D scaffolds and 2D films for tissue engineering applications, in particular to repair urethral strictures or defects. The polymer tested was a graft copolymer of polylactic acid (PLA) synthesized with the rationale to improve the toughness of the related PLA homopolymer. The LMP-3055 graft copolymer (in bulk) demonstrated to have negligible cytotoxicity (bioavailability >85%, MTT test). Moreover, the LMP-3055 sterilized through gamma rays resulted to be cytocompatible and non-toxic, and it has a positive effect on cell biofunctionality, promoting the cell growth. 3D scaffolds and 2D film were prepared using different LMP-3055 polymer concentrations (7.5, 10, 12.5 and 15%, w/v), and the effect of polymer concentration on pore size, porosity and interconnectivity of the 3D scaffolds and 2D film was investigated. 3D scaffolds got better results for fulfilling structural and biofunctional requirements: porosity, pore size and interconnectivity, cell attachment and proliferation. 3D scaffolds obtained with 10 and 12.5% polymer solutions (3D-2 and 3D-3, respectively) were identified as the most suitable construct for the cell attachment and proliferation presenting pore size ranged between 100 and 400μm, high porosity (77–78%) and well interconnected pores. In vitro cell studies demonstrated that all the selected scaffolds were able to support the cell proliferation, the cell attachment and growth resulting to their dependency on the polymer concentration and structural features. The degradation test revealed that the degradation of polymer matrix (ΔMw) and water uptake of 3D scaffolds exceed those of 2D film and raw polymer (used as control reference), while the mass loss of samples (3D scaffold and 2D film) resulted to be controlled, they showed good stability and capacity to maintain the physical integrity during the incubation time. [Copyright &y& Elsevier]

Abstract: Polymer electrolytes were prepared from thermoplastic polyurethane with addition of mixture of N-ethyl(methylether)-N-methylpyrrolidinium trifluoromethanesulfonimide (PYRA12O1TFSI) ionic liquid, lithium bis(trifluoromethanesulfoneimide) salt and propylene carbonate. MCM-41 mesoporous silica was added in proportions ranging from 5 to 20wt.% with respect to TPU. The electrolytes were characterized by thermogravimetric analysis, differential scanning calorimetry, linear voltammetry and impedance spectroscopy. The MCM-41 addition to the system was found to improve the electrochemical stability of the membranes and to reduce the gel electrolyte/metallic Li interfacial resistance. The filler influence on the ion transport processes was discussed according to results obtained by equivalent circuit fitting of impedance spectra. [Copyright &y& Elsevier]

Abstract: Polymer electrolytes were prepared from thermoplastic polyurethane with addition of mixture of ionic liquid N-ethyl(methylether)-N-methylpyrrolidinium trifluoromethanesulfonimmide (PYRA12O1TFSI), lithium bis(trifluoromethanesulfoneimide) salt and propylene carbonate. The electrolytes characterization was performed by thermogravimetric analysis, differential scanning calorimetry and scanning electron microscopy. The electrical properties were investigated in detail by impedance spectroscopy with the aid of equivalent circuit fitting of the impedance spectra. A model describing temperature evolution of ionic conductivity and the properties of electrolyte/blocking electrode interface was developed. The electrochemical stability of the electrolytes was studied by linear voltammetry. Our results indicate that the studied electrolytes have good self-standing characteristics, and also a sufficient level of thermal stability and a fairly good electrochemical window. The ionic conductivity increases with increasing amount of mixture, and the character of temperature dependence of conductivity indicates decoupling of ion transport from polymer matrix. For studied system, the highest value of ionic conductivity measured at room temperature was 10−4 Scm−1. [Copyright &y& Elsevier]

Abstract: In this work, steam reforming of natural gas is investigated with an application to a small-scale hydrogen production unit of industrial interest, coupled to PEM fuel cells. We carried out a thermodynamic analysis to estimate the efficiency of this overall process, which consists of a reformer reactor and two water gas shift reactors. We compare two different configurations: physical (PSA) or chemical (PROX) removal of CO from syngas. We find a similar global efficiency for both processes, although the PSA version has a relatively better performance. [Copyright &y& Elsevier]

Abstract: Accuracy requirements for aerosol optical depth (AOD) in polar regions are much more stringent than those usually encountered in established sun photometer networks, while comparability of data from different archive centres is a further important issue. Therefore, two intercomparison campaigns were held during spring 2006 at Ny-Ålesund (Svalbard) and autumn 2008 at Izaña (Tenerife) within the framework of the IPY POLAR-AOD project, with the participation of various research institutions routinely employing different instrument models at Arctic and Antarctic stations. As reported here, a common algorithm was used for data analysis with the aim of minimizing a large part of the discrepancies affecting the previous studies. During the Ny-Ålesund campaign, spectral values of AOD derived from measurements taken with different instruments were found to agree, presenting at both 500nm and 870nm wavelengths average values of root mean square difference (RMSD) and standard deviation of the difference (SDD) equal to 0.003. Correspondingly, the mean bias difference (MBD) varied mainly between −0.003 and +0.003 at 500nm, and between −0.004 and +0.003 at 870nm. During the Izaña campaign, which was also intended as an intercalibration opportunity, RMSD and SDD values were estimated to be equal to 0.002 for both channels on average, with MBD ranging between −0.004 and +0.004 at 500nm and between −0.002 and +0.003 at 870nm. RMSD and SDD values for Ångström exponent α were estimated equal to 0.06 during the Ny-Ålesund campaign and 0.39 at Izaña. The results confirmed that sun photometry is a valid technique for aerosol monitoring in the pristine atmospheric turbidity conditions usually observed at high latitudes. [Copyright &y& Elsevier]

Abstract: The passage of a volcanic plume produced by the eruption of Eyjafjallajökull volcano in April 2010 was measured by the sun–sky radiometers of the new European SkyRad (ESR) network. This network consists of several European sites located in the U.K., Poland, Spain and Italy, and therefore was particularly suitable for monitoring the transport of volcanic ash generated by this particular volcano. The atmospheric aerosol characteristics at each site affected by the passage of the volcanic cloud, during and after the eruption, have been reconstructed. For the U.K. ESR sites three events were identified by the sun–sky radiometers: the first, from April 15 to April 16 2010, related to the advection of fine particles; whilst the second, from April 17 to April 19 and the third from April 23 to April 24 related to the arrival of coarse particles. During the transport from Northern Europe to Italy, columnar radiative properties clearly changed due to both deposition and mixing with local aerosol. [Copyright &y& Elsevier]

Abstract: Sol–gel is a promising technique for the synthesis of organic–inorganic hybrid materials both of class I and II. In materials of class I organic molecules are physically entrapped in an inorganic matrix, while in those of class II organic and inorganic parts are connected by covalent bonds. In this paper a sol–gel procedure to obtain SiO2–PEG hybrids of class I, in which PEG is simply mixed at the sol stage, is compared to a sol–gel procedure to obtain SiO2–PEG hybrid materials of class II, where a particular sol–gel Si–C precursor is synthesized. XPS analyses showed the different distribution of the organic phase in the SiO2 matrix and the bond between PEG and SiO2 for hybrids of class II. The PEG molecule in hybrid of class II showed an enhanced thermal stability up to 350°C. Doping with a lithium salt was performed on hybrids of class II, and the ionic conductivity was measured. [Copyright &y& Elsevier]

Dielectric measurements have been carried out on (AgI)x(AgPO3)1−x glasses, with x=0, 0.2 and 0.5, from 10 Hz up to the microwave frequency region using a broadband dielectric technique up to 500 MHz and waveguide equipments up to 40 GHz. A wide part of the dispersive region in the real conductivity is then available in the case of undoped silver metaphosphate glass, revealing that even at room temperature, a nearly constant loss behaviour is approached. At higher frequencies, a power law dependence of conductivity on frequency is observed, with exponent q>1, in the glasses with lower dc conductivity, but a maximum slope of only 2/3 is attained for the heavily doped (AgI)0.5(AgPO3)0.5 glass. Further broadband investigations at lower temperatures are expected to give a clearer picture of conductivity dispersion features and of their eventual dependence on the structural modifications induced by the doping with AgI. [Copyright &y& Elsevier]

Poster: Clinical track: CNS PO-0903: Cellular phones radiofrequency exposure and malignant brain tumor:sistematic review and metaanalisys A. Guaineri, G. Peretto, L. Triggiani, A. Alghisi, D. Tomasini, P. Borghetti, M. Maddalo, S. Pedretti, C. Tomasi, L. Spiazzi, S.M. Magrini, M. Buglione. [Extracted from the article]