Titanium (Ti) and its alloys are amongst the most commonly-used biomaterials in orthopedic and dental applications. The Ti-aluminum-vanadium alloy (Ti6Al4V) is widely used as a biomaterial for these applications by virtue of its favorable properties, such as high tensile strength, good biocompatibility and excellent corrosion resistance. TiO2 nanotube (NTs) layers formed by anodization on Ti6Al4V alloy have been shown to improve osteoblast adhesion and function when compared to non-anodized material. In his study, NTs were grown on a Ti6Al4V alloy by anodic oxidation for 5 min using a super-oxidative aqueous solution, and their in vitro biocompatibility was investigated in pig periosteal osteoblasts and cartilage chondrocytes. Scanning electron microscopy (SEM), energy dispersion X-ray analysis (EDX) and atomic force microscopy (AFM) were used to characterize the materials. Cell morphology was analyzed by SEM and AFM. Cell viability was examined by fluorescence microscopy. Cell adhesion was evaluated by nuclei staining and cell number quantification by fluorescence microscopy. The average diameter of the NTs was 80 nm. The results demonstrate improved cell adhesion and viability at Day 1 and Day 3 of cell growth on the nanostructured material as compared to the non-anodized alloy. In conclusion, this study evidences the suitability of NTs grown on Ti6Al4V alloy using a super-oxidative water and a short anodization process to enhance the adhesion and viability of osteoblasts and chondrocytes. The results warrant further investigation for its use as medical implant materials.

Purpose -The aim of this work is to study the corrosion and scaling factors, mechanisms and processes affecting the materials, equipment and installations of the Cerro Prieto geothermal field (GTF). Design/methodology/approach -The physicochemical characteristics of the geothermal well and fluids were analysed, recorded and related to the corrosion and scaling phenomena. Findings -The high temperature and salinity of the steam-brine mixture and the presence of hydrogen sulphide and carbon dioxide impart a severe level of corrosivity. Originality/value -Corrosion and scaling control assure an efficient production regime, provide for the durability of the GTF engineering materials and equipment and contribute to environmental quality.

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Other critical problems, that impact on infrastructure and industry are climate change, global warming and greenhouse emissions, all interrelated phenomena.This chapter presents important aspects of corrosion in industrial infrastructure, its causes, impacts, control, protection and prevention methods. Materials in industryMetallic materials play a key role in the development of a country and its sustained growth in the context of the global economy. Table 1 shows a classification and the properties of dif-

Biological extracts have recently shown a great potential for rapid biosynthesis of silver nanoparticles (AgNPs) with antibacterial activity. AgNPs were synthetized by reduction effect of secondary metabolites produced by the Nigrospora sp. fungus, from Moringa oleifera stem as a reducing agent and silver nitrate (AgNO 3 ) (1 mM) as salt precursor. The synthesis of nanoparticles (NPs) was monitored through analysis of the UV-Vis spectroscopy absorption in the 436 to 440 nm range indicating the presence of AgNPs in the colloidal aqueous solutions. Fourier transform infrared spectroscopy (FTIR) spectra were performed to identify the compounds responsible for the bio reduction of the Ag + . The morphology and sizes of AgNPs were characterized by scanning electron microscopy (SEM), energy dispersive of X-ray spectroscopy (EDS), dynamic light scattering (DLS), and colloid stability by zeta potential measurements. The NPs obtained were spherical in shape with size in the 3 to 70 nm range. Antibacterial activity was confirmed by evaluation of their effect against Escherichia coli, Klebsiella cloacae and Staphylococcus epidermidis. The proposed green synthesis of AgNPs from secondary metabolites produced by the Nigrospora sp. fungus from M. oleifera stem can be strongly recommended as a potential method for biomedical application.

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The results of a study on the corrosion of metallic copper used in the fabrication of contraceptive intrauterine devices (lUDs) are shown. The corrosion behaviour of IUD TCu 380 A and Nova Τ was evaluated in uterine synthetic solution in order to simulate the uterus conditions. The corrosion processes were evaluated by polarisation, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) electrochemical techniques.In addition, surface analyses were performed by scanning electron microscopy (SEM), and the chemical composition of the corrosion products was determined by energy dispersive X-ray (EDX). Copper exposed to the synthetic solution showed an active corrosion process during the test due to the presence of chloride ions. The formation of a spongy gel corrosion product on the copper surface was observed in simulated solution and characterized, comparing the different results obtained in the electrochemical tests and surface analysis. The objective of this study is to generate knowledge on the lUD's electrochemical corrosion mechanisms and parameters in order to assure its successful function as a contraceptive.

A virtual instrumentation (VI) system called VI localized corrosion image analyzer (LCIA) based on LabVIEW 2010 was developed allowing rapid automatic and subjective error-free determination of the pits number on large sized corroded specimens. The VI LCIA controls synchronously the digital microscope image taking and its analysis, finally resulting in a map file containing the coordinates of the detected probable pits containing zones on the investigated specimen. The pits area, traverse length, and density are also determined by the VI using binary large objects (blobs) analysis. The resulting map file can be used further by a scanning vibrating electrode technique (SVET) system for rapid (one pass) “true/false” SVET check of the probable zones only passing through the pit's centers avoiding thus the entire specimen scan. A complete SVET scan over the already proved “true” zones could determine the corrosion rate in any of the zones.