t) 2006 - 04 Documents

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    SYNTHESIS AND COMPARATIVE STUDY OF THE INHIBITIVE PROPERTIES OF ISOMERIC SCHIFF BASES AND ITS CYCLISATION PRODUCTS (Article)
    (Journal of Corrosion Science and Engineering, 2006) Thamaraiselvi, N; Parameswari, K; Chitra, S; Selvaraj, A
    The corrosion behaviour of mild steel in 1M sulphuric acid solution and its inhibition by Schiff bases and thiazolidinones was studied using weight loss method at various temperatures (303-333K), by electrochemical and non - electrochemical techniques. The percentage inhibition efficiency of the inhibitors increased with increase in inhibitor concentration. Potentiodynamic polarization studies revealed that though the Schiff bases and thiazolidinones act as mixed type inhibitors they are slightly anodic in nature. Adsorption of these inhibitors on the mild steel surface followed the Langmuir adsorption isotherm. The thermodynamic parameters such as activation energy (Ea) and free energy of adsorption (ΔG°ads) were calculated. The synergistic effect of halide ions on the inhibition efficiency of thiazolidinones was also studied.
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    BIODEGRADATION OF LIGNOCELLULOSIC COIR PITH BY USING FUNGAL FORMS (Article)
    (EM International, 2006) Vinodhini, S; Padma Devi, S N; Padma, Srinivasan
    The present study deals with degradation of coir poll by Humicola sp. Trichoderma viride and Aspergillus terreus. The lignin, cellulose, organic carbon content and evolution of carbon-di-oxide were estimated in pith degraded aad non-degraded coir pith. The content of lignin and cellulose were found to be low in lignin and cellulose during different period of biodegradation.
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    STUDY OF SUBSTITUENT EFFECTS IN SUBSTITUTED DIBENZAL ACETONES (Article)
    (Journal of the Indian Chemical Society, 2006-10-16) Ananthakrishna Nadar, P; Renuga, V
    The present work involves a detailed study of the ultra-violet absorption spectra of various substituted dibenzylidene ketones derived from acetone, ethyl methyl ketone, diethyl ketone, cyclopentanone and cyclohexanone by condensing with several meta- and para-substituted benzaldehydes in n -hexane and in ethanol to ascertain the transition dominant in these solvents. These ketones exist as equilibrium mixtures of s-cis, cis and s-cis, trans conformations. The ultraviolet absorption spectra of the ketones exhibit two bands due to π*← π transition around 250 and 320 nm. The 320 nm band is prominent in all the cases. There is no indication of π* ← π transition in any of the spectra. The 320 nm band is structureless in all the cases except those shown by the dibenzylidene ketones derived from cyclopentanone in hexane. Therefore it can be inferred that the dibenzylide ketones derived from all the ketones except those derived from cyclopentanone are non-planar.
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    MOBILE CODE AND SECURITY ISSUES (Book Chapter)
    (IGI Global, 2007) Samundeeswari, E S; Mary Magdalene Jane, F
    Over the years, computer systems have evolved from centralized monolithic computing devices supporting static applications, into client-server environments that allow complex forms of distributed computing. Throughout this evolution, limited forms of code mobility have existed. The explosion in the use of the World Wide Web, coupled with the rapid evolution of the platform-independent programming languages, has promoted the use of mobile code and, at the same time, raised some important security issues. This chapter introduces mobile code technology and discusses the related security issues. The first part of the chapter deals with the need for mobile codes and the various methods of categorising them. One method of categorising the mobile code is based on code mobility. Different forms of code mobility, like code on demand, remote evaluation, and mobile agents, are explained in detail. The other method is based on the type of code distributed. Various types of codes, like source code, intermediate code, platform-dependent binary code, and just-in-time compilation, are explained. Mobile agents, as autonomously migrating software entities, present great challenges to the design and implementation of security mechanisms. The second part of this chapter deals with the security issues. These issues are broadly divided into code-related issues and host-related issues. Techniques, like sandboxing, code signing, and proof-carrying code, are widely applied to protect the hosts. Execution tracing, mobile cryptography, obfuscated code, and cooperating agents are used to protect the code from harmful agents. The security mechanisms, like language support for safety, OS level security, and safety policies, are discussed in the last section. In order to make the mobile code approach practical, it is essential to understand mobile code technology. Advanced and innovative solutions are to be developed to restrict the operations that mobile code can perform, but without unduly restricting its functionality. It is also necessary to develop formal, extremely easy-to-use safety measures.