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Geethamani P.,Bharathiar University | Kasthuri P.K.,Lrg Government Arts College For Women
Journal of the Taiwan Institute of Chemical Engineers | Year: 2016

A comparative study of expired asthalin drug was studied for its inhibitive effect on mild steel in 1M HCl and 1M H2SO4 medium, using the metrics of weight loss and electrochemical techniques. The various parameters such as corrosion rate, inhibition efficiency and surface coverage were calculated. The weight loss method shows that the inhibition efficiency increases with the increase of inhibitor concentration, time and temperature. A mixed mode of inhibition mechanism was proposed for the effect of examined asthalin drug, as revealed by potentiodynamic polarization technique. Thermodynamic parameter such as free energy value was negative, that indicates spontaneous adsorption of inhibitor on mild steel surface. The nature of adsorption of the inhibitor on the mild steel surface was in conformity with Langmuir adsorption isotherm. The surface morphology of the mild steel, with and without the inhibitor, was studied using scanning electron microscopy (SEM). © 2016 Taiwan Institute of Chemical Engineers. Source

Kanchana P.,Alagappa University | Elakkina Kumaran A.,Lrg Government Arts College For Women | Sekar C.,Alagappa University
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2013

Trivalent metal ion (Al, Cr, Fe) doped potassium hydrogen phthalate (KAP) crystals have been grown from aqueous solution at room temperature. Powder XRD and ICP-OES studies confirmed the metal ion doping into KAP crystals. The presence of functional groups in the crystal has been observed by FTIR analysis. Optical transmission studies were carried out by allowing the UV-NIR ray of wavelength between 190 and 1000 nm to pass through the (010) face of the grown KAP crystals. Dielectric constant value of Fedoped KAP at 100 Hz was found to be significantly higher than that of undoped and Cr and Al-doped KAP. TG-DTA studies show the decomposition temperatures to be 255, 270, 258 and 287 °C for pure, Al3+, Cr3+ and Fe3+ doped KAP crystals respectively. Microhardness studies reveal that the Cr3+ and Fe3+ doped crystals have higher hardness values than that of undoped and Al-doped KAP. The grown crystals were also subjected to second harmonic generation (SHG) efficiency tests. © 2013 Published by Elsevier B.V. Source

Kanchana P.,Alagappa University | Elakkina Kumaran A.,Lrg Government Arts College For Women | Hayakawa Y.,University of Shizuoka | Sekar C.,Alagappa University | Sekar C.,University of Shizuoka
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2013

Single crystals of potassium hydrogen phthalate (KAP), a semi-organic compound, have been grown by slow evaporation method at room temperature from aqueous solution in the presence of divalent metal ionic impurities Ba 2+, Ca2+ and Mg2+. Elemental analysis by inductively coupled plasma optical emission spectroscopy (ICP-OES) proves the incorporation of these impurities into the grown crystals. Powder X-ray diffraction studies confirmed the phase formation and metal ions doping into KAP crystals. Thermogravimetric-differential thermal analysis (TG-DTA) shows the onset decomposition temperatures to be 255, 238, 251 and 250 °C for pure, Ba2+, Ca2+ and Mg2+ doped KAP crystals respectively. Microhardness studies revealed that all the three doped crystals have improved hardness values than that of undoped KAP crystal. Ca-KAP crystal exhibited the highest second harmonic generation (SHG) conversion efficiency of 16 mV with the output power of nearly half of the standard potassium dihydrogen phosphate (KDP) crystal. The grown crystals were also subjected to Fourier transform infrared (FTIR) spectroscopy, ultra violet-visible-near infrared (UV-NIR) spectroscopy studies and dielectric studies. Among the three investigated metal ion impurities, Ca2+ ion seem to have positive influence on the growth, mechanical, thermal, dielectric and SHG characteristics of KAP which makes it suitable for applications. © 2012 Elsevier B.V. All rights reserved. Source

Kanagaraj R.,Salem College | Ganesan S.,Government College of Technology, Coimbatore | Esther P.,Lrg Government Arts College For Women
Journal of Optoelectronics and Advanced Materials | Year: 2015

The nano crystalline NiFeCr thin films were synthesised on the surface of aluminium substrate at different bath temperature like 30, 40, 50 and 60°C by applying a constant current density of 0.5 A/dm2. All the coated NiFeCr thin films were subjected to the structural, mechanical and magnetic characterization analysis (EDAX, SEM, XRD, VHT and VSM). The SEM pictures of NiFeCr thin films shows that, the film have crack free, uniform and bright surface morphology with fine grain size. The XRD pattern reveals the BCC structure of NiFeCr thin films with three predominant diffraction peaks. The VSM data of NiFeCr clearly shows their magnetic nature. The NiFeCr thin films coated at high bath temperature have highest saturation magnetisation value with lower coercivity. Because of its low coercivity with highest magnetisation value, the NiFeCr thin films may used for the manufacturing of MEMS devices. Source

Sridevi A.P.,Lrg Government Arts College For Women | Palaniswami S.,Salem College
International Journal of Applied Engineering Research | Year: 2014

Wireless sensor networks consist of some nodes that have limited processing capability, small memory and low energy source. These nodes are deployed randomly and often densely in the environment. In monitoring applications, sensor nodes sense data from the environment periodically and then transmit them to a base station which is called sink node. Thereby data transmission consumes node’s energy based on transmission distance. In most wireless sensor networks, the energy source of the node is limited and cannot be minimized. Here, we have proposed the cluster based multipath routing scheme for power efficiency for minimizing the power consumption in WSNs. It consists of three phases. These phases are the cluster topology and selection of cluster head, energy based multipath route and Power utilization procedure. The proposed scheme attains the balance between power efficiency, load balancing and network lifetime in WSNs. By simulation results, the proposed CMRP achieves better data delivery ratio, improved network lifetime, less end to delay and energy consumption in terms of mobility, time, throughput, packet interval and number of nodes than EEMCRP and FAF-EBRP. © Research India Publications. Source

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