XRD

Pigment identification on Campana reliefs from the Palatine Hill and Colosseum Valley in Rome

This article shows the first pigment identification of the Campana reliefs, Roman architectural earthenware plaques. The Campana reliefs polychromy were investigated by applying a multidisciplinary approach involving non-invasive and micro-destructive techniques to some fragments with traces of colour found on the north-eastern slopes of the Palatine Hill in Rome.

Structure, drug absorption, bioactive and antibacterial properties of sol-gel SiO2/ZrO2 materials

Zirconia widely used in biomedical applications has three crystalline forms, but the transformation from tetragonal to monoclinic is a serious problem in the biomedical field. In this regards, silica was added to stabilize the tetragonal zirconia phase. In fact, in this study four SiO2/ZrO2 composites with different percentages of zirconia were synthesized with the sol-gel method. The aim of the present study was to check the suitability of these materials as a vector in the adsorption of an active drug.

SAXSLab Sapienza

Italiano

SAXSLab Sapienza is a laboratory for structural characterization which operates the X-ray diffractometer Xeuss 2.0 HR P300K Q-Xoom (XENOCS), purchased thanks to the grant “Grandi Attrezzature d’Ateneo 2015”.

The instrument is capable of Small Angle X-Ray Scattering (SAXS), Wide Angle X-ray Scattering (WAXS) and Grazing Incidence Small Angle Scattering (GISAXS) experiments. These techniques are widely applicable for the characterization of matter at the nano- and meso-scale.

 

Structural features of selected protic ionic liquids based on a super-strong base

Protic ionic liquids (PIL) were prepared from a super-strong base 1,7-diazabicyclo[5.4.0]undec-7-ene (DBU) and super-strong acids, trifluoromethane sulfonic acid (TfOH), and (trifluoromethanesulfonyl)-(nonafluorobutylsulfonyl)imide, (IM14H), ([DBUH][TfO] and [DBUH][IM14], respectively; the latter for the first time) and their chemical and physical properties and structural features have been explored using a synergy of experimental and computational tools.

First evidence of electrode reconstruction in mesoporous NiO after operation as photocathode of dye-sensitized solar cells

For the first time it is shown that the NiO films operating as
photocathodes in dye-sensitized solar cells (DSCs), alter their Xray
diffraction (XRD) pattern upon occurrence of the photoelectrochemical
reaction of reduction. In particular, it has been
observed that mesoporous NiO sensitized with Fast Green (FG)
presents splitting and broadening of its characteristic XRD
peaks after device operation in p-type DSC (p-DSC) and tandem
DSC (t-DSC). The nature of the changes in the diffraction

New Insights into the Structure of Glycols and Derivatives: A Comparative X-Ray Diffraction, Raman and Molecular Dynamics Study of Ethane-1,2-Diol, 2-Methoxyethan-1-ol and 1,2-Dimethoxy Ethane

In this study, we report a detailed experimental and theoretical investigation of three glycol
derivatives, namely ethane-1,2-diol, 2-methoxyethan-1-ol and 1,2-dimethoxy ethane. For the first
time, the X-ray spectra of the latter two liquids was measured at room temperature, and they were
compared with the newly measured spectrum of ethane-1,2-diol. The experimental diffraction patterns
were interpreted very satisfactorily with molecular dynamics calculations, and suggest that in liquid

Silicon nanowires to detect electric signals from living cells

The ability to merge electronic devices with biological systems at the cellular scale is an interesting perspective. Potential applications span from investigating the bio-electric signals in excitable (and non-excitable) cells with an insofar-unreached resolution to plan next-generation therapeutic devices. Semiconductor nanowires (NWs) are well suited for achieving this goal because of their intrinsic size and wide range of possible configurations.

Multi-technique characterisation of commercial alizarin-based lakes

The characterization of ancient and modern alizarin-based lakes is a largely studied topic in the literature. Analytical data on contemporary alizarin-based lakes, however, are still poor, though of primary importance, since these lakes might be indeed present in contemporary and fake paintings as well as in retouchings. In this work we systematically investigate the chemical composition and the optical features of fifteen alizarin-based lakes, by a multi-analytical technique approach combining spectroscopic methods (i.e.

A physical-based interpretation of mechanism and kinetics of Cr(VI) reduction in aqueous solution by zero-valent iron nanoparticles

The aim of this paper is to show the results obtained by investigating the reduction of hexavalent Chromium [Cr(VI)] by iron nano-particles in aqueous solution, interpreted in light of the particle-grain model. The diffusional and geometric parameters that govern and describe the reacting system were estimated from the evidences deriving from the characterization and the experiments conducted, allowing assumptions based on physical principles. Such procedure rendered the particle-grain model a valid choice for the interpretation of the results obtained.

Amorphous steel coatings deposited by cold-gas spraying

Cold-gas spray (CGS) deposition of amorphous steel coatings starting from a commercial feedstock powder containing boron, tungsten, and silicon was investigated. Microstructural
characterization, carried out by X-ray diffraction (XRD), transmission electron microscopy, and backscattered electron diffraction (EBSD) analysis, confirmed the amorphous nature of deposited
coatings. The amorphization phenomenon is related to high-strain/strain-rate deformation with shear instability caused by very high particle kinetic energy, with a mechanism that resembles the severe

© Università degli Studi di Roma "La Sapienza" - Piazzale Aldo Moro 5, 00185 Roma