Date(s) - 16/12/2020
14:30 - 17:00
Categories No Categories
Piattaforma webex, Stanza virtuale
H 14:20 Apertura prof. Marcello Crucianelli
Development of innovative analytical approaches for the characterization and the protection of typical food products. The main purpose of the research is the development of chemometric-based innovative analytical methodologies aimed at the analysis of typical food products. In particular, the use of multivariate data analysis to process the spectroscopic fingerprints collected by different techniques (mid-infrared spectroscopy, near infrared spectroscopy and inductively coupled plasma optical emission spectrometry) was exploited to trace local agro-foods, such as emmer and chickpeas, and to detect adulterations in the Altino bell pepper.
Investigating the sources of the cosmic rays The excitement about the multimessenger astrophysics is currently growing: the observed rates of the cosmic rays, neutrinos and gamma rays are comparable, supporting the search for a common origin of these messengers. The construction of a software to compute the cosmic-ray interactions in a toy-model source is
proposed. The novel feature of this proposal is to aim for a unique tool treating different environments. By including also, the fit of the measurements from the Pierre Auger Observatory and IceCube, suggestions for future experiments, like CTA, to investigate specific candidate source classes could be provided in the next future.
Synthesis, characterization and testing of magnetically recoverable heterogeneous oxidation catalysts. Heterogeneous catalysis is increasing its importance due to positive impact on economy and environment. Since not all relevant chemical processes employ heterogeneous catalysts, supporting homogeneous active species is becoming fundamental. We performed the synthesis and the full characterization of silica-coated magnetic nanoparticles for anchoring and easy recovery of the catalytically active moiety, testing also their chemical inertia towards test oxidation rection environment. Once we ensured the stability of the support, we successfully tested and optimized the final catalyst for oxidation of cyclooctene in different conditions.
H 15.30 -15:40 chat online
H 15:40 Chair Sergio Ciuchi.
Unveiling the molecular mechanism of O2 formation and release in natural photosynthesis
A key step in natural photosynthesis is the water-splitting reaction into molecular oxygen, electrons and hydrogen equivalents. Understanding the molecular mechanisms behind this photoreaction will unravel the secrets of solar energy conversion in biochemistry and may inspire the design of artificial bio-mimetic materials for green energy production. Photosynthetic water oxidation occurs in the Mn4Ca core of the Photosystem II complex where, through five subsequent steps, four electrons are sequentially removed until oxygen evolution. Here, using multiscale atomistic calculations, we investigated the molecular mechanism of
the O2 formation and release in the last steps of the catalytic cycle of Photosystem II.
Surface-science investigations on advanced materials: from fundamental research to applications in catalysis, gas sensing, desalination, and Terahertz photodetection
Surface science is an interdisciplinary research field at the boundary between condensed matter physics, physical chemistry and materials science. We investigated chemical reactions and collective electronic excitations (plasmons) at the surface of advanced materials “beyond graphene”, namely bulk crystals of topological semimetals (including noble-metal dichalcogenides) and van der Waals semiconductors. The joint use of several experimental tools (spectroscopies and microscopies) with surface sensitivity and in operando conditions, complemented by density functional theory, provided a comprehensive picture on chemical
reactivity, ambient stability and electronic properties of these novel materials. Gained information was exploited to devise applications for which surface-related processes and excitations play a pivotal role, specifically in the fields of (i) electrocatalysis, (ii) gas sensing, (iii) desalination through membrane distillation, (iv) recovery of minerals from brine, and (v) plasma-wave Terahertz photodetection.
Renormalization group inspired autonomous equations for secular effects in de Sitter space.
We develop a method for treating a series of secularly growing terms obtained from quantum perturbative calculations: autonomous first-order differential equations are constructed such that they reproduce this series to the given order. The exact solutions of these equations are free of secular terms and approach a finite limit at late times. This technique is illustrated for the well-known problem of secular growth of correlation functions of a massless scalar field with a quartic self-interaction in de Sitter space. For the expectation value of the product of two fields at coinciding space-time points, we obtain a finite late-time result that is very close to the one following from Starobinsky’s stochastic approach.
Sergio Ciuchi conclusioni