FTIR

Spectral Characterization of Mid-Infrared Bloch Surface Waves Excited on a Truncated 1D Photonic Crystal

The many fundamental roto-vibrational resonances of chemical compounds result in strong absorption lines in the mid-infrared region (λ ∼ 2–20 μm). For this reason, mid-infrared spectroscopy plays a key role in label-free sensing, in particular, for chemical recognition, but often lacks the required sensitivity to probe small numbers of molecules. In this work, we propose a vibrational sensing scheme based on Bloch surface waves (BSWs) on 1D photonic crystals to increase the sensitivity of mid-infrared sensors. We report on the design and deposition of CaF2/ZnS 1D photonic crystals.

Fourier-transform infrared spectroscopy of skeletal muscle tissue: Expanding biomarkers in primary mitochondrial myopathies

Primary mitochondrial myopathies (PMM) are a group of mitochondrial disorders characterized by a predominant skeletal muscle involvement. The aim of this study was to evaluate whether the biochemical profile determined by Fourier-transform infrared (FTIR) spectroscopic technique would allow to distinguish among patients affected by progressive external ophthalmoplegia (PEO), the most common PMM presentation, oculopharyngeal muscular dystrophy (OPMD), and healthy controls. Thirty-four participants were enrolled in the study.

Sol-Gel synthesis, spectroscopic and thermal behavior study of SiO2/PEG composites containing different amount of chlorogenic acid

In this work, new phenol-based materials have been synthesized by the sol-gel method, in which different amounts of the phenolic antioxidant chlorogenic acid (CGA) (from 5 wt % to 20 wt %) were embedded in two different silica matrices: pure silica and silica-based hybrids materials, containing 50 wt % of polyethylene glycol (PEG). The incorporation of CGA in different sol-gel matrices might protect them from degradation, which could cause the loss of their properties. The two series of materials were chemically characterized by Fourier transform infrared (FTIR) spectroscopy.

Street art graffiti. Discovering their composition and alteration by FTIR and micro-Raman spectroscopy

Paints used in street art are modern materials subjected to degradation processes, which are very complex and difficult to predict without taking into account of several factors. This study investigates three outdoor murals in Lazio, – namely “graffiti”, a word now used to indicate a spontaneous street art tendency consisting in images and writings realized by spray paints in public spaces to provoke passersby -with the aim to discover materials application techniques and chemical composition and figure out whether alteration phenomena occurred.

Lucio Fontana and the light. Spectroscopic analysis of the artist's collection at the National Gallery of Modern and Contemporary Art

In this work the results deriving from the characterization of materials used by Lucio Fontana to realize some of his artworks are presented. Specifically, object of analyses are three artworks from the collection of National Gal- lery of Modern and Contemporary Art in Rome, whose complex composition required the combination of differ- ent diagnostic techniques for a complete characterization.

Influence of the heat treatment on the particles size and on the crystalline phase of TiO2 synthesized by the sol-gel method

Titanium biomaterials' response has been recognized to be affected by particles size, crystal structure, and surface properties. Chemical and structural properties of these nanoparticle materials are important, but their size is the key aspect. The aim of this study is the synthesis of TiO2 nanoparticles by the sol-gel method, which is an ideal technique to prepare nanomaterials at low temperature. The heat treatment can affect the structure of the final product and consequently its biological properties.

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.

The use of ash at Late Lower Paleolithic Qesem Cave, Israel—An integrated study of use-wear and residue analysis

Employing an integrated approach to investigate the use of Late Lower Paleolithic flint tools
found at the site of Qesem Cave (Israel), we revealed a particular trace pattern related to
the employment of ashes at the site. Using a designated collection of replica items and combining
use-wear and residue (morphological analysis, FTIR, SEM-EDX) analyses, we
revealed the intentional use of ashes in preserving foods for delayed consumption as well
as hide for delayed processing. Our interpretation, we believe is the most plausible one

From a-Si:H to a-SiOx:H: the role of CO2 and H2 in PECVD deposition process

Recently a-SiOx:H has attracted interest in heterojunction solar cells fabrication, because of its effective crystalline silicon surface passivation and larger optical bandgap than a-Si:H. Both amorphous layers are commonly deposited by PECVD from silane dissociation in hydrogen dilution. to obtain a-SiOx:H film, CO2 as source of oxygen is added to gas mixture, that heavily modifies the film growth, the composition and hydrogen inclusion, which influence the passivation properties.

Comparison between a-SiOx:H and a-Si:H as Passivation Buffer Layer for Heterojunction Solar Cells

In crystalline silicon based heterojunction solar cells the surface passivation quality is fundamental to obtain high efficiency. Intrinsic a-Si:H, as obtained by PECVD process from silane dissociation, is a good candidate for surface passivation, but UV absorption of this material limits the current generation. Moreover, surface passivation quality can be compromised when fabrication steps, following the a-Si:H deposition, exceed the a-Si:H deposition temperature.

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