Activated carbon has been a fascinating material, especially for the removal of different pollutant species from gaseous and aqueous phases. Activated carbons can be prepared from a variety of cellulosic materials. This study is an effort to investigate the characteristics of activated carbon prepared from an agricultural waste material, coconut coir. The surface area and porosity of the activated carbon were determined by nitrogen adsorption isotherms at 77 K. The pore size distribution was determined by a N2 adsorption isotherm that shows the pore width, surface area, and total pore volume of the activated carbon. The BET surface area of synthesized activated carbon was found to be 205.27 m2·g−1. After activation, both micropores and a small volume of mesopores are formed in the product. Thermogravimetric analysis was used to monitor the course of pyrolysis of coconut coir and ZnCl2-impregnated coconut coir. Important physicochemical properties of the activated carbon were confirmed by Fourier transform IR spectroscopy and X-ray diffractometry.

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Nowadays, Web services have used drastically for various online applications like banking, e-bill processing. All online services need robust security architecture for handling sensitive data like user name, password. But, The Web service has security problems that need to be solved. The existing security scheme lacks to defend the attacks from replay and password guessing attacks. In this study we proposed a new scheme for a secure authentication procedure for the web service to enhance the security of the existing schemes. The proposed system has been implemented with the Dynamic Nonce for validating the user with username and password which is embedded with WS-Security. The Dynamic Nonce has been implemented with the user's mouse movement by satisfying the condition given in the proposed scheme. It has changed for every session because it is generated from user's mouse movements. The system has analyzed with possible attacks. The proposed dynamic nonce based authentication scheme is suitable for lower.