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Introduction: In recent years, there has been a growing research interest on the applications of a range of nanostructured materials in construction industry (i.e., asphalt concrete, bricks, concrete, timber, steel, and mortar), manufacturing, electronics, cosmetics, and medicine. The use of nanoscale structures in the construction industry offers exceptional physicochemical characteristics for the modification of construction materials. Nanomaterials, which are being used in cement and concretes, are carbon nanomaterials (Graphene, CNTs, CNFs), nanosilica, nano Al2O3, nanometakaoline, nano CaCO3, nano Fe2O3 and nanoTiO2. Methods: These materials improve the properties of concretes by modifying the microstructure and also improve the mechanical properties. The improvement in mechanical and durability properties of concretes in the presence of nanoparticles is due to their smaller size ( Results: Nevertheless, all these nanoscale particles find their way (either directly or indirectly) to various environmental matrices, such as groundwater, surface water, rivers, seas, lakes, and soil. The potential bioaccumulation of metal oxide nanostructures results in undesirable effects on animals, aquatic biota, plants, and humans. Therefore, it has become crucial to determine toxicity levels during the use of these multifunctional nanoscale materials. Conclusion: This study presents an overview of the advantages and disadvantages of nanomaterials in concretes and related materials. A particular emphasis has been given to discuss the potential toxicity risks of nanomaterials used in building construction materials.

Corrosion of complex electronic equipment is an increasingly serious problem, causing expensive damage. Corrosion occurs through out the entire life cycle during different stages of manufacturing, assembly, transport and stor- age of components and assemblies and during field operations of the equipment. Presence of moisture, chloride, sulphur dioxide, hydrogen sulphide and other airborne corrosives, meteorological parameters etc influence the occurrence of cor- rosion. The present review describes the current understanding mechanism of corrosion of electronic components and equipments in different environmental conditions. The various corrosion testing methods and methods of corrosion pre- vention in these electronic devices have also been elaborated.

The inhibition efficiency of Eosin in controlling corrosion of carbon steel immersed in well water, has been evaluated by mass loss method both in absence and presence of zinc ion. A synergistic effect exists between Eosin (EN) and Zn 2+ . The inhibition efficiency (IE) of the EN - Zn 2+ system decreases with increase in immersion period. Addition of N-cetyl-N,N,N-trimethylammonium bromide (CTAB), sodium dodecyl sulphate (SDS), sodium sulphite (Na2SO3) does not change the excellent inhibition efficiency of the EN-Zn 2+ system. Polarization study suggests that the EN-Zn 2+ system functions as an anodic inhibitor system. AC impedance spectra reveal the presence of a protective film on the metal sur- face. FTIR spectra indicate that the protective film consists of Fe 2+ - EN complex and Zn(OH)2.