Urban areas are facing challenges for the provision of public services, with water scarcity arising as one of the main problems. A twin track approach of supply and demand management is essential, and water-loss management contributes to reducing water demand. However, small municipalities from developing countries have technical, information, and financial limitations to locate and monitor water losses. This paper presents the estimation of real and apparent losses in a small municipality from a developing country in a data-scarce situation. For this, several tools were used, allowing data integration that resulted in a water balance, from which water losses were estimated at 46%, and four alternatives for water-loss reduction were developed. A cost-benefit analysis and financial indicators were estimated for the proposed alternatives, resulting in a water savings of 19%, a payback period of 3 years and an internal rate of return of 39%. The proposed strategies have potential to improve water quantity and quality, the technical stability of the system, utility performance, and water security.

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Compressive and shear stresses as well as the generation of heat are critical issues in the failure mechanism of carbon fiber reinforced epoxy composites under reciprocating sliding. In this work, the mechanical stress distribution and maximum surface temperature generated on the wear track by reciprocating sliding against stainless steel counter body are modelled numerically. The computational results are used to directly compare them to experimental data to discuss the contact status and failure mechanism during the sliding process applying different sliding frequency and external environment. The debonding between the carbon fibers and the epoxy is modelled considering a cohesive interface modelling. We demonstrate numerically that the sliding frequency has a significant effect on heat generation. Experimentally, at higher frequencies, a more pronounced debonding and crack formation take place in the sub-surface region which is not the case at lower sliding frequencies. Water acts as a cooling agent and decreases the debonding because it functions as a plasticizer agent for the epoxy matrix.@en

B-doped diamond has become the ultimate material for applications in the field of microelectromechanical systems (MEMS), which require both highly wear resistant and electrically conductive diamond films and microstructures. Despite the extensive research of the tribological properties of undoped diamond, to date there is very limited knowledge of the wear properties of highly B-doped diamond. Therefore, in this work a comprehensive investigation of the wear behavior of highly B-doped diamond is presented. Reciprocating sliding tests are performed on micro- and nanocrystalline diamond (MCD, NCD) films with varying B-doping levels and thicknesses. We demonstrate a linear dependency of the wear rate of the different diamond films with the B-doping level. Specifically, the wear rate increases by a factor of 3 between NCD films with 0.6 and 2.8 at. % B-doping levels. This increase in the wear rate can be linked to a 50% decrease in both hardness and elastic modulus of the highly B-doped NCD films, as determined by nanoindentation measurements. Moreover, we show that fine-grained diamond films are more prone to wear. Particularly, NCD films with a 3× smaller grain size but similar B-doping levels exhibit a double wear rate, indicating the crucial role of the grain size on the diamond film wear behavior. On the other hand, MCD films are the most wear-resistant films due to their larger grains and lower B-doping levels. We propose a graphical scheme of the wear behavior which involves planarization and mechanochemically driven amorphization of the surface to describe the wear mechanism of B-doped diamond films. Finally, the wear behavior of the nucleation surface of NCD films is investigated for the first time. In particular, the nucleation surface is shown to be susceptible to higher wear compared to the growth surface due to its higher grain boundary line density.@en