«Il patrimonio culturale tra esigenze di tutela e sua valorizzazione»

Seminario inaugurale del Corso di «Legislazione dei beni culturali, ambientali e turismo

Frequency shifts in noble-gas magnetometers

Polarized nuclei are a powerful tool in nuclear spin studies and in searches for beyond-the-standard model physics. Noble-gas comagnetometer systems, which compare two nuclear species, have thus far been limited by anomalous frequency variations of unknown origin. We studied the self-interactions in a $^3$He-$^{129}$Xe system by independently addressing, controlling and measuring the influence of each component of the nuclear spin polarization. Our results directly rule out prior explanations of the shifts, and demonstrate experimentally that they can be explained by species dependent self-interactions. We also report the first gas phase frequency shift induced by $^{129}$Xe on $^3$He.Comment: v.

Cittadinanza attiva e Costituzione

Il percorso formativo si propone di fornire le conoscenze basilari del Diritto costituzionale in una prospettiva di maturazione negli studenti dei fondamenti culturali della cittadinanza attiva, che rappresenta una condizione indispensabile nel processo di sviluppo della persona e nell’ambito delle relazioni sociali, con particolare riguardo a quelle che interessano il contesto del lavoro. Il programma si articolerà in un primo incontro con il coordinatore scientifico Prof. Alberto Lucarelli di impostazione seminariale, in occasione del quale verranno illustrati i principi fondativi del modello di Stato democratico rappresentativo che sono sanciti nella nostra Carta costituzionale. A seguire, verranno realizzati dei moduli laboratoriali su specifici temi che verranno trattati sulla base di un più diretto coinvolgimento degli studenti, attraverso ad esempio simulazioni, realizzazione di mappe concettuali, etc

Characterization of Microgels in Ionic Liquid

Microgels are thermoresponsive polymeric nanoparticles whose size in aqueous solution is dependent on temperature. The microgels were studied using both dynamic light scattering (DLS) and scanning electron microscopy (SEM) to better understand the nanoparticles dynamics. The first part of the study focused on developing a controlled preparation procedure which would generate reproducible SEM images on a wet sample. The ionic liquid was mixed with a dilute solution of microgels and water was dried using nitrogen gas. This technique allowed a large volume of microgels to easily transition from their natural water solvent to a low vapor pressure ionic solvent. The second part of the study attempts to correlate the diffusion found from microgels in ionic liquid using scanning electron microscopy to the statistical average diffusion measured with dynamic light scattering. The microgels in ionic liquid observed with SEM exhibited the same radius that was measured with DLS for microgels in a water based solvent.https://engagedscholarship.csuohio.edu/u_poster_2018/1033/thumbnail.jp

Developing affordable wet-sample electron microscopy integrated with a temperature controlled sample holder

Scanning electron microscopy (SEM) is widely used to analyze the size, shape and composition of material systems. However, using this tool for analyzing systems such as particles suspended in solution, requires drastic sample alterations, such as precipitation and fixation. Besides altering their environment, this exposes the particles to the harsh conditions within an electron microscope, such as high vacuum and electron beam exposure. To this end, the first goal of this study was to develop methodologies for imaging wet samples using electron microscopy. This is realized by creating a sandwich structure containing the solution of interest between a partially electron transparent window and a silicon substrate. The ability of the developed imaging cells to provide good imaging conditions is demonstrated with a variety of samples including polystyrene spheres, polymeric microgels and spindle shaped nanoparticles. As some of the systems investigated are temperature sensitive, the second goal of the project was to develop a temperature controlled stage that can be integrated with the SEM. In the future this heating stage will be used alongside the wet samples to image microgels above and below their critical solution temperature.https://engagedscholarship.csuohio.edu/u_poster_2015/1030/thumbnail.jp