Polyvinyl ester green composites were synthesized with walnut shell powder (WSP) by in-situ polymerization technique. The green composites have been evaluated for mechanical properties such as tensile strength, tensile modulus and hardness. Sliding wear loss, specific wear rate and coefficient of friction were investigated by using computerized pin-on–disc machine at normal applied loads of 20,...

We look at various ways of enhancing the strength of conventional cryptosystems such as DES by building a new system which has longer keys and which uses the original system as a building block. We propose a new variant of two-key triple encryption which is not vulnerable to the meet in the middle attack by van Oorschot and Wiener. Under an appropriate assumption on the security of DES, we can ...

in the present work, the effect of aluminum content, austenitizing temperature and austempering time and temperature on the mechanical properties and hardness of fe-c-al grey cast iron was investigated. for this purpose, three alloys containing 1, 2 and 4 weight percent of aluminum were provided. the tensile samples were austenitized at 850?c and 900?c for 120 min, followed by austempering proc...

Steels are heavily used in infrastructure and the transportation industry, and enhancing their fatigue resistance is a major challenge in materials engineering. In this study, by introducing a gradient microstructure into 304 austenitic steel, which is one of the most widely used types of stainless steel, we show that a strength gradient substantially enhances the fatigue life of the material. ...

Despite the numerous advantages of using concrete with high strength capacity, the brittle behavior of high strength concrete (HSC) and higher production cost has limited its use in the construction industry. This research aims to develop a cost-effective approach for production of high strength self-compacting concrete with desirable performance in either compressive or tensile loading conditi...