This degree project focuses on air pollution and the new technologies employment in construction to oppose this problem that causes not only environmental impacts, but also human health, vegetation and fauna. Nanotechnology is a branch that emerges from new technologies and has made its own way in the construction industry, through the implementation of nanometric materials and additives that improve and generate new properties in common building materials such as steel, concretes, mortars, paintings, etc. In this project a concrete and a mortar were made by adding titanium dioxide (TiO2), which acts as a catalyst when it is combined with cement and ultra violet rays, and its main function is to oxidize suspended contaminating particles, that's why is categorized as a decontaminant. Also, TiO2 can improve concrete's properties.To verify the TiO2 effects on the concrete, four cylinders of typical concrete and added concrete were elaborated, and these were tested at the typical ages of failure and the obtained results were compared. In the same way, an added mortar was made, and it was placed on panels and then, left exposed for eight days in an air monitoring area, and with the data obtained the corresponding analysis was performed.

The term “icephobicity” has emerged in the literature recently. An extensive discussion took place on whether the icephobicity is related to the superhydrophobicity, and the consensus is that there is no direct correlation. Besides the parallel between the icephobicity and superhydrophobicity for water/ice repellency, there are similarities on other levels including the hydrophobic effect/hydrophobic interactions, mechanisms of protein folding and ice crystal formation. In this paper, we report how ice adhesion is different from water using force balance analysis, and why superhydrophobic surfaces are not necessary icephobic. We also present experimental data on anti-icing of various surfaces and suggest a definition of icephobicity, which is broad enough to cover a variety of situations relevant to de-icing including low adhesion strength and delayed ice crystallization and bouncing.

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In a book published in 1906, Richard Meade outlined the history of portland cement up to that point1. Since then there has been great progress in portland cement-based construction materials technologies brought about by advances in the materials science of composites and the development of chemical additives (admixtures) for applications. The resulting functionalities, together with its economy and the sheer abundance of its raw materials, have elevated ordinary portland cement (OPC) concrete to the status of most used synthetic material on Earth. While the 20th century was characterized by the emergence of computer technology, computational science and engineering, and instrumental analysis, the fundamental composition of portland cement has remained surprisingly constant. And, although our understanding of ordinary portland cement (OPC) chemistry has grown tremendously, the intermediate steps in hydration and the nature of calcium silicate hydrate (C-S-H)*, the major product of OPC hydration, remain clouded in uncertainty. Nonetheless, the century also witnessed great advances in the materials technology of cement despite the uncertain understanding of its most fundamental components. Unfortunately, OPC also has a tremendous consumption-based environmental impact, and concrete made from OPC has a poor strength-to-weight ratio. If these challenges are not addressed, the dominance of OPC could wane over the next 100 years. With this in mind, this paper envisions what the 21st century holds in store for OPC in terms of the driving forces that will shape our continued use of this material. Will a new material replace OPC, and concrete as we know it today, as the preeminent infrastructure construction material?