Osteointegrative dental implants are widely used in implantology for their well-known excellent performance once implanted in the host. Remarkable bacterial colonization along the transgingival region may result in a progressive loss of adhesion at gum-implant interface and an increase of the bone area exposed to pathogens. This phenomenon may negatively effect the osteointegration process and cause, in the most severe cases, implant failure. The presence of bacteria at implant site affect the growth of new bone tissue and consequently, the achievement of a mechanically stable bone-implant interface, key parameters for a suitable implant osteointegration. In the present work, a novel surface treatment has been developed and optimized in order to convert the amorphous titanium oxide in a crystalline layer enriched in anatase capable of providing not only antibacterial properties but also of stimulating the precipitation of apatite when placed in simulated body fluid. The collected data have shown that the tested treatment results in a crystalline anatase-type titanium oxide layer able to provide a remarkable decrease in bacterial attachment without negatively effecting cell metabolic activity. In conclusion, the surface modification treatment analyzed in the present study might be an elegant way to reduce the risk of bacterial adhesion and increase the lifetime of the transgingival component in the osteointegrated dental implant.

Localized corrosion of stainless steel, namely pitting and crevice, affects seriously the performance of these materials in service. In this paper, the design of experiment (DOE) is used to study the influence of temperature, pH and chloride concentration on the pitting and crevice corrosion of AISI 304L (UNS S30403) stainless steel. DOE approach enables to reduce the number of tests (anodic potentiodynamic polarization) necessary to study the effect of several parameters on the passivity breakdown potential. The use of DOE provided a regression equation that was analyzed by comparison with laboratory and literature results. Among all these parameters, the temperature has the most significant effect on pitting corrosion resistance.

Memristors have recently gained growing interest due to their potential application as electronic synapses to build artificial neural networks for artificial intelligence systems. However, modulating the conductivity of memristors in a dynamic way to emulate biological synaptic behaviors is very challenging. Here we show the first fabrication of memristive electronic synapses using a dielectric film (TiO2–x ) synthesized via an electrochemical anodization method. Pt/anodic TiO2–x /Ti memristive synapses show reliable and reproducible memristive behavior and fast switching times below 90 ns. By applying ramped voltage stresses, multilevel conductance states have been achieved (using different current compliances or reset voltages), and by applying pulsed voltage stresses, the potentiation and depression rates could be accurately controlled by tuning the pulse amplitudes. The switching is governed by homogeneous charge rearrangements at the TiO2–x /Ti interface and TiO2–x thickness modulation. It is concluded that the anodic oxidation method may be a cheap and effective route to fabricate competitive electronic synapses.

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A novel nanohybrid composite of TiO 2 , SiO 2 , γ-Fe 2 O 3 , and reduced graphene oxide (TiO 2 @Si:Fe:rGO) is fabricated by the sol–gel method. The properties of the coated film were examined by structural and self-cleaning analyses using simulated discoloration/soiling and roofing tests. The fabricated transparent TiO 2 @Si:Fe:rGO composite showed excellent photoactivity and wettability, behaving well in self-cleaning applications. The addition of SiO 2 improved the crystalline structure and surface hydroxylation of TiO 2 nanoparticles. γ-Fe 2 O 3 decreased the recombination rate of e – /h + pairs, and significantly improved photocatalytic activity under visible light. Moreover, rGO sheets as excellent electron acceptors and transporters also reduced recombination, as well as affected wettability, achieving superhydrophilicity under irradiation. The coated substrate showed excellent resistance to simulated acid rain and significantly preserved the substrate from soiling in roofing tests.