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Multistitched three-dimensional (3D) woven E-glass/polyester/nanosilica composite (MNS) was developed. Its mechanical and impact performances were characterized for particular end-use applications. It was found that the warp-weft directional tensile strength and modulus of MNS structure were higher than those of the off-axis directions. In addition, there was not a big difference between warp and weft directional bending and short beam strengths of MNS structure. The MNS structure had a small damaged area under low velocity impact load. The failure was confined at a narrow area because of multistitching and nanomaterial and resulted in the catastrophic fiber breakages in the normal direction of the applied load of the structure. The results from the study indicated that the multistitching and the addition of nanosilica in the composite structure improved its damage tolerance.

Many cities, especially larger metropolises, parks are very important recreational areas where people usually have closer contact with flora. Therefore, the pollution level in the parks can have a greater effect on human health. Heavy metals are ubiquitous with the environment, as a result of both natural and anthropogenic activities, and humans are exposed to them through various pathways. Essentially, these areas are assumed to be less exposed to routine contaminants, but especially in metropolises, this assumption could prove false considering these areas are stuck within the confines of a city full of pollutant activity such as intense traffic. In this study; the relationships between heavy metal pollution levels (Cd, Cr, Cu, Ni, Pb, Zn) and the pH and electrical conductivity (EC) of soil samples were investigated from the parks on the Asian side of Istanbul. For this purpose, the most frequently visited 16 parks were selected as sampling sites. In the second part of the study, linear correlation is used for the data analysis.