Search results for " FT-IR spectroscopy"

showing 4 items of 4 documents

Confinement of chiral molecules in reverse micelles: FT-IR, polarimetric and VCD investigation on the state of dimethyl tartrate in sodium bis(2-ethy…

2008

Abstract The state of d and l -dimethyl tartrate confined within dry sodium bis(2-ethylhexyl) sulfosuccinate (AOT) reverse micelles dispersed in CCl 4 has been investigated by FT-IR spectroscopy, polarimetry, and vibrational circular dichroism (VCD). Measurements have been performed at 25 °C as a function of the solubilizate-to-surfactant molar ratio ( R ) at a fixed AOT concentration (0.158 M). The analysis of experimental data is consistent with the hypothesis that both enantiomers of dimethyl tartrate are mainly entrapped in the reverse micelles and located in proximity to the surfactant head-group region. The formation of this interesting self-organized chiral nanostructure involves som…

Circular dichroismInorganic chemistryInfrared spectroscopyTartrateMicellechemistry.chemical_compoundColloid and Surface ChemistryMonomerchemistryPulmonary surfactantVibrational circular dichroismPhysical chemistryEnantiomerDimethyl tartrate Sodium bis(2-ethylhexyl) sulfosuccinate Reverse micelles Chiral nanostructures FT-IR spectroscopy Vibrational circular dichroism Optical rotationColloids and Surfaces A: Physicochemical and Engineering Aspects
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Volatiles in pantellerite magmas: A case study of the Green Tuff Plinian eruption (Island of Pantelleria, Italy)

2013

Abstract The Green Tuff (GT) Plinian eruption, the largest in magnitude at Pantelleria, erupted 3 to 7 km3 DRE of pantellerite magma and a small volume of trachyte. Fifty-nine anorthoclase-hosted melt inclusions from the two basal pumice members were analyzed by FT-IR spectroscopy in order to assess the pre-eruptive H2O content in the pantellerite melt. Microanalytical methods were used to determine major element, Cl, F and S contents. Melt inclusions and glassy groundmasses have a nearly homogeneous pantelleritic composition (peralkaline index = 1.9-2.2) and variable water contents ranging from 1.4 to as high as 4.2 wt %, i.e. much higher than the 1.4 wt % of earlier published studies. The…

LavaSettore GEO/07 - Petrologia E PetrografiaGeochemistryTrachyteMagma chamberStrombolian eruptionGeophysicsEffusive eruptionGeochemistry and PetrologyPumiceMagmaThe Green Tuff (GT) Plinian eruption the largest in magnitude at Pantelleria erupted 3 to 7 km 3 DRE of pantellerite magma and a small volume of trachyte. Fifty-nine anorthoclase-hosted melt inclusions from the two basal pumice members were analyzed by FT-IR spectroscopy in order to assess the pre-eruptive H2Ocontent in the pantellerite melt. Microanalytical methods were used to determine major element Cl F and S contents. Melt inclusions and glassy groundmasses have a nearly homogeneous pantelleritic composition (peralkaline index = 1.9-2.2) and variable water contents ranging from 1.4 to as high as 4.2 wt % i.e. much higher than the 1.4 wt % of earlier published studies. The chlorine content is constant at about 1 wt %. Combined Cl and H2O data were used to estimate a confining pressure of about 50 MPa (depth around 2-3 km) for the GT magma chamber. The chamber was characterized by a compositional zoning with a dominant pantellerite overlying a trachyte magma. Soon after the GT eruption intra-caldera volcanism was dominated by the eruption of voluminous trachyte lavaflows while pantellerite melt production resumed after about 20 ka with numerous low-volume mildly explosive (Strombolian) to effusive eruptions. Comparison with data from the literature reveals that despite the differentexplosivity the post-caldera Strombolian eruptions and the GT Plinian eruption were fed by pantelleritic magmas with similar water contents. Chlorine and CO2contents suggest that the young magma reservoirs feeding the Strombolian to effusive activity were deeper (h≥4.5 km) than the much larger (based on erupted volumes) magma chamber which fed the GT eruptionGeologyMelt inclusionsJournal of Volcanology and Geothermal Research
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MULTIDISCIPLINARY STUDY FOR THE DATING AND THE RESTORATION OF THE SAN VITO WOODEN PULPIT OF MUSEO DIOCESANO OF PALERMO

2017

The aim of the present research is to investigate the execution techniques of San Vito wooden pulpit in the Museo Diocesano of Palermo and to provide helpful information to dating it in addition to technical, historical and artistic evaluations. In particular, this paper describes the application of analytical techniques (imaging diagnostics techniques, Scanning Electron Microscopy coupled with X-ray Energy Dispersive spectroscopy Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy and Fourier Transform Infrared Spectroscopy) to better understand the pulpit characteristics, both support and decoration, useful to plan and perform the correct restoration.

Wooden pulpit SEM-EDS FT-IR spectroscopy Museo Diocesano of Palermo
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Accelerated weathering of PP based nanocomposites: Effect of the coupling agent

2013

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nanocomposites weathering stability morphology mechanical properties FT-IR spectroscopy
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