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The purpose of this paper is to study the potential of alumina (Al₂O₃) in nanometer size in automotive brake friction materials.

Four brake linings containing alumina differing in particle size (355 µm and 80 nm) and various amount (5 and 10 Wt.%) were designed and produced. The hardness, density and porosity of the samples were measured. All samples were tested on a full-scale brake dynamometer with gray cast iron disc to determine the tribological properties. Detailed examinations on the worn surface were analyzed using a scanning electron microscopy.

It was concluded that all performance parameters were beneficially affected because of nano alumina.

This paper emphasizes the importance of nano-composites in the automotive industry and helps industrial firms and academicians working on wear of materials.

Among the components used for a car brake lining, the chemical and structural properties of the abrasives, jointly with the morphology and size of the particles influence the friction parameters and stability of the composite. This paper aims to investigate the effect of nano SiO2 particles in brake pads on friction and wear properties.

In this paper, the effects of SiO₂ (Silica) particles of varying size on the friction-wear properties of polymeric friction composites are investigated. Four friction composites were prepared containing (5, 10 Wt.%) micro silica (MS) particles and (5, 10 Wt.%) nano silica (NS) particles. The samples were produced by a conventional procedure for a dry formulation following dry-mixing, pre-forming and hot pressing. Friction and wear characteristics of the specimens against to a disk made of cast iron were studied. Friction coefficient, specific wear rate and hardness of specimens were obtained. Detailed examinations on the worn surface were analyzed using a scanning electron microscope.

The results of test showed that the inclusion of nano silicon carbide (SiC) powder improved the wear performance significantly. Friction coefficient (μ) of NS samples was higher than the MS samples. Micro-SiC showed poor performance and μ. High wear performance was exhibited in materials containing 5 Wt.% NS and 10 Wt.% NS.

This paper emphasizes the importance of nano-composites in the automotive industry and helps to industrial firms and academicians working on wear of materials.

Contemporary urban change is predominantly driven by migration and capital accumulation, with associated urban (re-)development projects – such as new-build gentrification – typically favouring the middle classes. Low-income residents in gentrifying neighbourhoods are often said to be displaced from their homes, either directly or indirectly, or to experience a loss of sense of place induced by the physical and social changes to the area. With the latter in mind, we investigate the perceived opportunities and threats of urban renewal experienced by stay-put communities in the wake of new developments and demonstrate how a loss of sense of place occurs via conflict between neighbours affected by the change. Our focus on transnational spaces comprising co-migrant Kurdish/Turkish communities in the two cities of Istanbul (Turkey) and Vienna (Austria) reveals not only how profoundly the impacts of neighbour conflict are felt as once-close and supportive neighbourly ties are severed but also how well-established neighbourly norms and obligations in transnational spaces accentuate the conflict in the first place. Moral codes that require neighbours to look after one another, along with local power dynamics of support in return for loyalty, set expectations that neighbours will take each other’s side when needed. Our findings reveal that the situatedness of residents to the development projects (in terms of proximity, residential tenure and openness to change) causes neighbours to take opposing sides and that the conflicts generated are accentuated by the perceived failure of neighbours to meet their neighbourly obligations. The result is a loss of sense of place and belonging for all residents – not just those detrimentally impacted by the development – wrought by rising hostility and avoidance among neighbours, and an overall weakening of neighbourly ties.

Poverty has been an important social problem from the beginning of humanity and will be till the end of the world. But the rapid change in technology took away the capability of human effort to cover his necessities alone. The people must improve their education, talent and capacity continuously. In this respect, today's globalizing poverty is more concrete and a difficult problem to solve than ever.