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Gino Mariotto

Publications and source records attributed to Gino Mariotto.

2 recordsLinked to original sources

Element- and enantiomer-selective visualization of ibuprofen dimer vibrations

In chemistry, biology and materials science, the ability to access interatomic interactions and their dynamical evolution has become possible with the advent of femtosecond lasers. In particular, the observation of vibrational wave packets via optical (UV-visible-IR) spectroscopies has been a major achievement as it can track the motion of nuclei within the system. However, optical spectroscopies only detect the effect of the interatomic vibrations on the global electronic surfaces. New tuneable, pulsed and polarized sources of short-wavelength radiation, such as X-Ray Free electron lasers, can overcome this limitation, allowing for chemical and, of primary importance in biochemistry, enantiomeric selectivity. This selectivity may be complemented by taking into account the chemical shifts of atoms belonging to different molecular moieties

cond-mat.soft

New method for characterization of magnetic nanoparticles by scanning magnetic microscopy

In this paper, we present a new method for the magnetic characterization of bulk materials, microstructures, and nanostructures. We investigated the magnetic and morphological properties of two colloidal dispersions of iron oxide (Fe3O4) magnetic nanoparticles (MNPs), synthesized by chemical precipitation (co-precipitation) and pulsed laser ablation (PLA) in liquid, by scanning magnetic microscopy (SMM) applied to a small sample with mass on the order of tens of μg. We evaluated the performance of this technique by comparing magnetization curves and measurements obtained with commercial magnetometers, considered standard. The errors obtained for the saturation and remanent magnetization were approximately 0.18 Am2/kg and 0.6 Am2/kg, respectively. The average size distribution of the NPs estimated from the magnetization curve measurements is consistent with the results obtained by traditional transmission electron microscopy (TEM). The technique can be extended to measure and analyze magnetization curves (hysteresis loops), thus enabling an even more accurate estimation of overall NP sizes.

physics.app-ph