Titanium and its alloys are the most popular biomaterials replacing hard tissues in implant surgeries. Clinicians are generally pleased by titanium mechanical properties and non-toxicity performances; on the other hand, there have been reported several cases of titanium implantation failure, phenomenon explained sometimes as "non adherence of human tissue to the metallic surface." Yet, researchers reported that titanium surfaces are favorable for osteoblasts adhesion. Therefore, titanium integration into the human body remains an unsolved problem. In the present study, biocompatibility tests were performed on titanium and TiO(2) nanotubes substrates, involving human bone marrow cells. The combination of a newly developed analytical model based on the hybrid interphase concept, applicable to systems consisting of inert materials when in contact with living tissues, together with experimental results, confirmed previous research studies and lead to the conclusion that osteoblasts adhere efficiently to titanium surfaces. However, the present results suggest that osteoblasts strong anchorage at the very first moment of their contact with the metallic material leads to their apoptosis. It is most probable that in several cases this is the reason of failed implantation surgeries involving titanium.

The effects of temperature and moisture on flexural and thermomechanical properties of neat and filled epoxy with both multiwall carbon nanotubes (CNT), carbon nanofibers (CNF), and their hybrid components were investigated. Two regimes of environmental aging were applied: Water absorption at 70 °C until equilibrium moisture content and thermal heating at 70 °C for the same time period. Three-point bending and dynamic mechanical tests were carried out for all samples before and after conditioning. The property prediction model (PPM) was successfully applied for the prediction of the modulus of elasticity in bending of manufactured specimens subjected to both water absorption and thermal aging. It was experimentally confirmed that, due to addition of carbon nanofillers to the epoxy resin, the sorption, flexural, and thermomechanical characteristics were slightly improved compared to the neat system. Considering experimental and theoretical results, most of the epoxy composites filled with hybrid carbon nanofiller revealed the lowest effect of temperature and moisture on material properties, along with the lowest sorption characteristics.

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In this paper the elaboration and characterization of TiO2 nanotubes as a function of anodizing conditions are studied taking into consideration electrolyte composition and voltage. The obtained results show that the nanotubes dimensions and surface features depend on elaboration conditions. The technique of surface characteristics investigation (2D and 3 D images) was atomic force microscopy which permitted roughness and porosity evaluation.