Optimization of modifier deposition on the alumina surface to enhance mechanical properties and cavitation resistance

Composites based on poly(methyl methacrylate), dimethyl itaconate matrix and alumina particles were prepared. Ferrous oxide-doped alumina particles (Al2O3Fe) and commercial alumina nanoparticles (Al(2)O(3)n) modified with (3-aminopropyl)trimethoxysilane (AM) and methyl esters of linseed oil fatty acids (biodiesel-BD) were used as reinforcement. The mechanical properties of the prepared composites, containing 1, 3 and 5 wt% of surface-modified alumina particles, are compared to a neat polymer matrix. The particles were characterized by single-beam Fourier transform infrared spectroscopy, thermogravimetry and differential scanning calorimetry. The mechanical properties of the composites were determined by micro-Vickers hardness and impact testing. The morphology of the surface of the composites exposed to cavitation was observed through a field emission scanning electron microscope. AFM analysis was used to compare surface features seen using the SEM and to interpret the surface degradation properties. The hardness, cavitation resistance and high-impact energy resistance of the composites are better in the case of AM surface modification of alumina fillers, but biodiesel modified particles have comparable mechanical properties and a stabilized Al-O-Si bond that could be important when a composite is exposed to humidity or a wet environment

Diet, Lifestyle, Smoking

Cardiovascular disease is the leading cause of death globally The past few decades have shown that especially low- and middle-income countries have undergone rapid industrialization, urbanization, economic development and market globalization. Although these developments led to many positive changes in health outcomes and increased life expectancies, they all also caused inappropriate dietary patterns, physical inactivity and obesity. Evidence shows that a large proportion of the cardiovascular disease burden can be explained by behavioural factors such as low physical activity, unhealthy diet and smoking. Controlling these risk factors from early ages is important for maintaining cardiovascular health. Even in patients with genetic susceptibility to cardiovascular disease, risk factor modification is beneficial. Despite the tremendous advances in the medical treatment of cardiovascular risk factors to reduce overall cardiovascular risk, the modern lifestyle which has led to greater sedentary time, lower participation in active transport and time spent in leisure or purposeful physical activity, unhealthy diets and increased exposure to stress, noise and pollution have diminished the beneficial effects of contemporary medical cardiovascular prevention strategies. Therefore attenuating or eliminating these health risk behaviours and risk factors is imperative in the prevention of cardiovascular diseases