background: motorcycle accidents and sport accidents lead yearly to many head injuries like head fractures and concussion. so finding the most proper helmet for reducing the injuries to head can be very helpful for head protection in such cases. methods: after 3d modeling of the helmet and head and meshing the model, a compressive impacting load of 1.31mpa was exerted on head and the model was ...

Activation of class F fly ash with the 10 M sodium hydroxide and sodium silicate and its geopolymeric products were analysed under quasi-isothermal mode of DSC, FTIR and TG/DTA techniques. Before adding in concrete, expanded polystyrene beads were prewetted with the styrenebutadienestyrene latex aimed at to improve their bonding with geopolymer. Lightweight mortars/concretes were made from geop...

Novel preparation method of microencapsules was developed on the basis of the liquid coalescence method followed by phase separation. Oil droplets of limonene dissolving expanded polystyrene as a shell material were forced to collide and coalesce with the Isopar oil droplets of core material in the continuous wates phase. When two kinds of oil droplets are collided and coalesced with each other...

fire behavior of different types of eps was evaluated with the use of iso 5660 cone calorimeter test method. considering the complexity of behavior of eps against high temperatures, several specimens were tested, so a betterjudgment on fire behavior of this material could be acquired. the effects of foam density, thickness of specimens and the level of heat flux on fire behavior of foam were ex...