The effects of oxygen partial pressure on the optical absorption edge and the UV emission energy of ZnO films

The optical absorption edge and ultraviolet (UV) emission energy of ZnO films deposited by direct current (DC) reactive magnetron sputtering at room temperature have been investigated. With the oxygen ratio increasing, the structure of films changes from zinc and zinc oxide coexisting phase to single-phase ZnO and finally to the highly (002) orientation. Both the grain size and the stress of ZnO film vary with the oxygen partial pressure. Upon increasing the oxygen partial pressure in the growing ambient, the visible emission in the room-temperature photoluminescence spectra was suppressed without sacrificing the band-edge emission intensity in the ultraviolet region. The peaks of photoluminescence spectra were located at 3.06---3.15 eV. From optical transmittance spectra of ZnO films, the optical band gap edge was observed to shift towards shorter wavelength with the increase of oxygen partial pressure.

Fe−TPP Coordination Network with Metalloporphyrinic Neutral Radicals and Face-to-Face and Edge-to-Face π−π Stacking

Artículo científico Inorg. Chem. 2013, 52, 8074−8081

System architecture and deployment scenarios for SESAME: Small cEllS coordinAtion for Multi-tenancy and Edge services

The surge of the Internet traffic with exabytes of data flowing over operators mobile networks has created the need to rethink the paradigms behind the design of the mobile network architecture. The inadequacy of the 4G UMTS Long term Evolution (LTE) and even of its advanced version LTE-A is evident, considering that the traffic will be extremely heterogeneous in the near future and ranging from 4K resolution TV to machine-type communications. To keep up with these changes, academia, industries and EU institutions have now engaged in the quest for new 5G technology. In this paper we present the innovative system design, concepts and visions developed by the 5G PPP H2020 project SESAME (Small cEllS coordinAtion for Multi-tenancy and Edge services). The innovation of SESAME is manifold: i) combine the key 5G small cells with cloud technology, ii) promote and develop the concept of Small Cellsas- a-Service (SCaaS), iii) bring computing and storage power at the mobile network edge through the development of nonx86 ARM technology enabled micro-servers, and iv) address a large number of scenarios and use cases applying mobile edge computing. Topics: