No abstract

Four heterocyclic compounds, namely 4-phenyl-5-acetyl/carbethoxy-3-methyl-6-hydroxyl-6-methyl-4,5,6,7-tetrahydro-2,1-benzoisoxazole and benzopyrazole (BIS1, BP1and BIS2, BP2), were synthesized and their influence on the inhibition of corrosion of mild steel in 1 M H 2 SO 4 was investigated by means of weight loss, potentiodynamic polarization, electrochemical impedance (EIS) and scanning electron microscopy (SEM). The values of activation energy and free energy of adsorption of these compounds were also calculated. Adsorption obeys Langmuir adsorption isotherm. The IE of the compounds was found to vary with concentration and temperature. Synergistic effect was also investigated for the four compounds at 0.05 mM concentration by weight loss method in 1 M H 2 SO 4 medium in presence of KI, KBr and KCl. Results obtained revealed that all the four compounds performed excellently as a corrosion inhibitor for mild steel in 1 M H 2 S0 4 and their efficiency attains more than 90% at 0.6 mM at 298 K. Polarisation studies showed them to be mixed type inhibitors.

P. B a la r a m e s h * 1, P. V e n k a te s h 2 a n d S . R e k h a 3In this study, the effect of imidazole and benzotriazole as primary stabilisers in saccharose and xylitol based copper electroless baths were studied. Copper methane sulphate was used as the complexing agent instead of copper sulphate and para formaldehyde was used as the reducing agent in the bath. The surface morphologies of copper deposits were characterised by SEM, AFM and XRD studies. The electrochemical characteristics were studied by cyclic voltametry to understand the role of the stabilisers in electroless deposition. In the saccharose bath, the imidazole and benzotriazole acted as inhibitors and best deposition was obtained at pH of 12-75. Benzotriazole afforded smoother and shiner deposits than imidazole. In xylitol bath, the stabilizers acted as accelerators and optimum deposition occurred at a pH of 13-25.

No abstract

Internet of Things (IoT) is an ecosystem of connected edge devices that are accessible through the internet. Recent research focusses on adding more smartness and intelligence to these edge devices making them susceptible to various kinds of security threats. These edge devices rely on cryptographic techniques to encrypt the pre-processed data collected from the sensors deployed in the field. Since the edge devices are resource constrained, low-cost implementations of cryptographic algorithms are desirable. This work proposes a novel low-cost implementation of a versatile symmetric encryption algorithm namely Advanced Encryption Standard (AES) using time-multiplexed architectures for edge devices. The optimization is carried out in a four-fold manner on AES encryption/decryption hardware based on the resource sharing mechanism with a modified Substitution box achieving a maximum of 1.053[Formula: see text]GHz operating frequency. The aim of this work is to develop an area-power efficient AES architecture with a reasonable throughput suitable for resource constrained applications. The proposed architectures are synthesized on a Virtex-6 FPGA board and the ASIC performance results are obtained using 180[Formula: see text]nm SCL technology library. Implementation results of the proposed AES core integrated with an UART module are shown as a proof of concept.