Ricerc@Sapienza

Conceptual activities on the DEMO fusion power plant design are progressing in Europe under the lead of the EUROfusion Consortium. According to the current EU DEMO plant design, the Primary Heat Transfer System (PHTS) transfers heat from the nuclear heat sources, i.e. breeding blanket, divertor and (optionally) vacuum vessel, to the Power Conversion System (PCS) responsible for generating electric energy. To mitigate issues related to the pulsed DEMO operation, adding the Energy Storage System (ESS) filled with molten salt, between the PHTS and PCS, has been proposed.

Spontaneous Raman is a well-established tool to probe molecular vibrations. Under resonant conditions, it is a largely used method for characterizing the structure of heme-proteins. In recent years, advances in pulsed laser sources allowed to explore vibrational features with complex techniques based on non-linear optical interactions, among which is stimulated Raman scattering (SRS).

We report on an orbital and temperature dependent study of the onset of coherent quasiparticles in V2O3 single crystal. By using polarized infrared spectroscopy we demonstrate that the electronic coherence temperature is strongly orbital dependent, being about 400 K for e?g orbitals and 500 K for the a1g. This suggests that V2O3 low energy electrodynamics can be described in terms of two electron liquids differently renormalized by electronic correlations.

This review provides a broad look on the recent investigations on the synthesis, characterization and physico-chemical properties of noble metal nanoparticles, mainly gold and silver nanoparticles, stabilized with ligands of different chemical nature. A comprehensive review of the available literature in this field may be far too large and only some selected representative examples will be reported here, together with some recent achievements from our group, that will be discussed in more detail.

Gold nanoparticles, capped by 3-mercapto propane sulfonate (Au-3MPS), were synthesized inside a swollen sulfonated poly(ether ether ketone) membrane (SPEEK). The formation of the Au-3MPS nanoparticles in the swollen sPEEK membrane was observed by spectroscopic and microscopic techniques. The nanocomposite containing the gold nanoparticles grown in the sPEEK membrane, showed the plasmon resonance ?max at about 520 nm, which remained stable over a testing period of three months.

A planar and low-cost parallel-plate waveguide (PPW) launcher based on substrate integrated waveguide (SIW) technology is proposed. It can launch the fundamental TEM mode with a collimated wave front into a PPW structure while also being low profile and easy to fabricate. The launcher is implemented using a network of SIW transmission lines and its design is based on the leaky-wave (LW) theory.

The Centralized Radio Access Network (C-RAN) provides a valid solution to overcome the problem of traditional RAN in scaling up to the needed processing resource and quality expected in 5G. The Common Public Rate Interface has been defined to transport traffic flows in C-RAN and recently some market solutions are available. Its disadvantage is to increase by at least 10 times the needed bandwidth and for this reason its introduction will be gradual and will coexist with traditional RAN solutions in which Ethernet traffic is carried towards the radio base stations.

The introduction of network function virtualization (NFV) leads to a new business model in which the Telecommunication Service Provider needs to rent cloud resources to infrastructure provider (InP) at prices as low as possible. Lowest prices can be achieved if the cloud resources can be rented in advance by allocating long-term virtual machines (VM). This is in contrast with the short-term VMs that are rented on demand and have higher costs. For this reason, we propose a proactive solution in which the cloud resource rent is planned in advance based on peak traffic knowledge.

We present a new class of photonic devices in which light is confined in channel waveguides, named LC:PDMS, made of a nematic liquid crystal (LC) core in a poly(dimethylsiloxane) flexible substrates. Monte Carlo techniques have been used to study LC orientation. Homeotropic alignment of LC molecules has been observed without any applied electric field. A theoretical study of LC orientation under an electric field between coplanar gold electrodes deposited by electroplating has been carried.

The incoming era of the fifth-generation fog computing-supported radio access networks (shortly, 5G FOGRANs) aims at exploiting computing/networking resource virtualization, in order to augment the limited resources of wireless devices through the seamless live migration of virtual machines (VMs) toward nearby fog data centers. For this purpose, the bandwidths of the multiple wireless network interface cards of the wireless devices may be aggregated under the control of the emerging MultiPathTCP (MPTCP) protocol.