Search results for " FTIR"
showing 10 items of 43 documents
Spectroscopic and microscopic characterization of BSA hydrogels: towards new biomaterials
2014
Effect of Hydration Procedure of Fumed Silica Precursor on the Formation of Luminescent Carbon Centers in SiO 2 :C Nanocomposites
2019
The effect of hydration procedure of fumed silica precursor on photoluminescent properties of carbonized silica (SiO2:C) nanocomposite after chemo/thermal treatments is studied. Main structural effect is the formation of chemical bonding of phenyl groups to silica surface via multiple CSiO bonding bridges. Synthesized samples demonstrate very broad photoluminescence (PL) bands in near ultraviolet and visible ranges with maximum intensity dependent on temperature of thermal annealing. Two main trends in luminescence properties are: 1) hydration-induced blue shift of PL in comparison with PL of unhydrated series; 2) red shift of PL bands with increasing synthesis temperature regardless hydr…
On the molecular structure of human neuroserpin polymers
2012
The polymerization of serpins is at the root of a large class of diseases; the molecular structure of serpin polymers has been recently debated. In this work, we study the polymerization kinetics of human neuroserpin by Fourier Transform Infra Red spectroscopy and by time-lapse Size Exclusion Chromatography. First, we show that two distinct neuroserpin polymers, formed at 45 and 85°C, display the same isosbestic points in the Amide I' band, and therefore share common secondary structure features. We also find a concentration independent polymerization rate at 45°C suggesting that the polymerization rate-limiting step is the formation of an activated monomeric species. The polymer structures…
A combination of portable non-invasive techniques to study on reverse glass paintings at Mistretta museum
2019
Abstract Reverse painting on glass is an old decorative technique used since the Roman time consisting in applying a cold paint layer on the reverse side. The Sicilian Regional Museum of forestry and pastoral traditions in Mistretta (Messina, Italy) houses the largest collection of reverse glass paintings in Italy with a total of 195 artworks. The artworks are attributed to the different Italian geographic area from north to south Italy. A combination of non-invasive analysis by using complementary portable spectroscopic instrumentations (mainly XRF and Raman Spectrometers) was applied on some selection of reverse glass paintings. The goal of the work is the characterization of the nature o…
Crypthecodinium cohnii Growth and Omega Fatty Acid Production in Mediums Supplemented with Extract from Recycled Biomass
2022
Crypthecodinium cohnii is a marine heterotrophic dinoflagellate that can accumulate high amounts of omega-3 polyunsaturated fatty acids (PUFAs), and thus has the potential to replace conventional PUFAs production with eco-friendlier technology. So far, C. cohnii cultivation has been mainly carried out with the use of yeast extract (YE) as a nitrogen source. In the present study, alternative carbon and nitrogen sources were studied: the extraction ethanol (EE), remaining after lipid extraction, as a carbon source, and dinoflagellate extract (DE) from recycled algae biomass C. cohnii as a source of carbon, nitrogen, and vitamins. In mediums with glucose and DE, the highest specific biomass gr…
Investigation of modern oil paints through a physico-chemical integrated approach. Emblematic cases from Valencia, Spain
2020
Abstract The study and the characterisation of modern and contemporary oil paintings is still a challenging issue, in particular considering the significant changes in paint production across the 19th and 20th centuries. This paper presents the results of the first physico-chemical integrated study of the artistic materials used in six paintings from the School of Art and Higher Design of Valencia (Escola d'Art i Superior de Disseny, EASD-Valencia), artworks created between 1871 and 1943 by four famous Valencian artists: Salustiano Asenso Arozarena, Salvador Abril I Blasco, Enrique Navas Escuriet and Jose Bellver Delmas. A wide range of inorganic and organic compounds was identified through…
SCIENTIFIC INVESTIGATIONS FOR THE RESTORATION OF SANTA CHIARA FROM THE SANTA CATERINA D’ALESSANDRIA MONASTERY IN PALERMO, ITALY
2022
The aim of this research was to assess the techniques and the materials used to realize the canvas painting Santa Chiara, from the Santa Caterina d’Alessandria Monastery and to verify the state of preservation, the possible decay processes and previous restorations. Consequently, an integrated analytical approach based on the use of non-invasive (diffused, indirect and ultraviolet light investigations) and micro-invasive techniques (optical microscopy, OM, scanning electron microscopy, SEM-EDX, Fourier- transform infrared spectroscopy FT-IR spectroscopy) were used. The oil painting on canvas dated XVI century: data suggests traditional painting technique, characterized by two priming prepar…