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Mahalakshmi G.,Karpagam University | Mahalakshmi G.,Government Arts College Autonomous | Balachandran V.,Arignar Anna Government Arts College
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2014

The FT-IR and FT-Raman spectra of 4-Aminomethylpiperidine have been recorded using Perkin Elmer Spectrophotometer and Nexus 670 spectrophotometer. The equilibrium geometrical parameters, various bonding features, the vibrational wavenumbers, the infrared intensities and the Raman scattering activities were calculated using Hartree-Fock and density functional method (B3LYP) with 6-311+G(d,p) basis set. Detailed interpretations of the vibrational spectra have been carried out with the aid of the normal coordinate analysis. The spectroscopic and natural bonds orbital (NBO) analysis confirms the occurrence of intra molecular hydrogen bonds, electron delocalization and steric effects. The changes in electron density in the global minimum and in the energy of hyperconjugative interactions of 4-Aminomethylpiperidine (4AMP) were calculated. The theoretical UV-Visible spectrum of the compound was computed in the region 200-400 nm by time-dependent TD-DFT approach. The calculated HOMO and LUMO energies show that charge transfer occur within the molecule. The dipole moment (μ) and polarizability (α), anisotropy polarizability (Δα) and hyperpolarizability (β) of the molecule have been reported. © 2014 Elsevier B.V. All rights reserved.


Ponnusamy P.,Government Arts College Autonomous | Selvamani R.,Karunya University
European Journal of Mechanics, A/Solids | Year: 2013

This work investigates the three dimensional wave propagation of a homogeneous transversely isotropic magneto thermo elastic cylindrical panel in the context of the linear theory of thermo elasticity. Three displacement potential functions are introduced to uncouple the equations of motion. A Bessel function solution with complex arguments is directly used to analyze the frequency equations with traction-free boundary conditions. The special cases have also been deduced for magneto elastic, thermo elastic and elastokinetic at various levels from the present analysis. The numerical example which demonstrates the present method is studied for the material magnetostrictive cobalt iron oxide (CoFe2O4). The computed non-dimensional phase velocity and attenuation coefficient are plotted in the form of dispersion curves. The coupling effect among thermal, magnetic and elastic in magneto thermo elastic material provides a mechanism for sensing thermo mechanical disturbances in the design of sensors and surface acoustic damping filters. © 2012 Elsevier Masson SAS. All rights reserved.


Arivazhagan M.,Aa Government Arts College | Subhasini V.P.,Jeppiaar Engineering College | Austine A.,Government Arts College Autonomous
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2012

The Fourier-transform infrared and FT-Raman spectra of 4-chloro-2- (trifluoromethyl) aniline (4C2TFA) were recorded in the region 4000-400 cm -1 and 3500-50 cm -1 respectively. Quantum chemical calculations of energies, geometrical structure and vibrational wavenumbers of 4C2TFA were carried out by density functional theory (DFT/B3LYP) method with 6-311+G(d,p) and 6-311++G(d,p) basis sets. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. The values of the total dipole moment (μ) and the first order hyperpolarizability (β) of the investigated compound were computed using B3LYP/6-311++G(d,p) calculations. The calculated results also show that 4C2TFA might have microscopic non-linear optical (NLO) behavior with non-zero values. A detailed interpretation of infrared and Raman spectra of 4C2TFA is also reported. The calculated HOMO-LUMO energy gap shows that charge transfer occurs within the molecule. © 2011 Elsevier B.V. All rights reserved.


Ponnusamy P.,Government Arts College Autonomous
Multidiscipline Modeling in Materials and Structures | Year: 2013

Purpose - This paper aims to describe the method for solving vibration problem of electro-magneto-elastic plate of polygonal (triangle, square, pentagon and hexagon) cross-sections using Fourier expansion collocation method (FECM). Design/methodology/approach - A mathematical model is developed to study the wave propagation in an electro-magneto-elastic plate of polygonal cross-sections using the theory of elasticity. The frequency equations are obtained from the arbitrary cross-sectional boundary conditions, since the boundary is irregular in shape; it is difficult to satisfy the boundary conditions along the surface of the plate directly. Hence, the FECM is applied along the boundary to satisfy the boundary conditions. The roots of the frequency equations are obtained by using the secant method, applicable for complex roots. Findings - From the literature survey, it is clear that the free vibration of electro-magneto-elastic plate of polygonal cross-sections have not been analyzed by any of the researchers, also the previous investigations in the vibration problems of electro-magneto-elastic plates are based on the traditional circular cross-sections only. So, in this paper, the wave propagation in electro-magneto-elastic plate of polygonal cross-sections is studied using the FECM. The computed non-dimensional frequencies are plotted in the form of dispersion curves and their characteristics are discussed. Originality/value - The researchers have discussed the circular, rectangular, triangular and square cross-sectional plates by the boundary conditions. In this problem, the author studied the vibrations of polygonal (triangle, square, pentagon and hexagon) cross-sectional plates using the geometrical relation which is applicable to all the cross-sections. The problem may be extended to any kinds of cross-sections by using the proper geometrical relations. © Copyright - 2013 Emerald Group Publishing Limited. All rights reserved.


Ponnusamy P.,Government Arts College Autonomous
Multidiscipline Modeling in Materials and Structures | Year: 2011

Purpose The purpose of this paper is to study the wave propagation in a homogeneous isotropic, thermo-elastic plate of arbitrary cross-sections using the two-dimensional theory of thermo-elasticity. Design/methodology/approach A mathematical model is developed to study the wave propagation in an arbitrary cross-sectional thermo-elastic plate by using two-dimensional theory of thermo-elasticity. After developing the formal solution of the mathematical model consisting of partial differential equations, the frequency equations have been derived by using the boundary conditions prevailing at the arbitrary cross-sectional surface of the plate for symmetric and antisymmetrical modes in completely separate forms using Fourier expansion collocation method. The roots of the frequency equation are obtained by using the secant method, applicable for complex roots. Findings The computed non-dimensional frequencies are compared with those results available in the literature in the case of elliptic cross-sectional solid plate with clamped edges without thermal field and this result is coincide with the results of Nagaya. The computed non-dimensional frequencies are plotted in the form of dispersion curves for longitudinal and flexural (symmetric and antisymmetric) modes of vibrations for the material copper. Originality/value The wave propagation in a plate of arbitrary cross-sections with the stress free (unclamped) and rigidly fixed (clamped) edges are analyzed with and without thermal field. © Copyright - 2011 Emerald Group Publishing Limited. All rights reserved.


Raja C.R.,Government Arts College Autonomous | Joseph A.A.,St. Joseph's College
Materials Letters | Year: 2010

An organic nonlinear optical material, l-valinium fumarate (abbreviated as LVF) has been successfully synthesized and good quality single crystals have been grown by low temperature solution growth method. The purified form of LVF is achieved by repeated crystallization. The cell parameters of LVF have been determined using single crystal X-ray diffraction technique and the crystal system is found as monoclinic. From the UV-Vis-NIR absorption spectrum, the good transparency is revealed from 300 nm to 1100 nm. The mode of vibration of different molecular groups present in LVF was identified by FT-IR spectral analysis. The thermogravimetric (TGA) and differential thermal analysis (DTA) studies show the thermal behavior and crystal was thermally stable up to 266 °C. Second harmonic generation (SHG) conversion test was made to explore the nonlinear optical behavior of this material using Kurtz and Perry method. © 2009 Elsevier B.V. All rights reserved.


Ponnusamy P.,Government Arts College Autonomous | Rajagopal M.,Government Arts College Autonomous
European Journal of Mechanics, A/Solids | Year: 2010

The wave propagation in an infinite, transversely isotropic solid cylinder of arbitrary cross-section immersed in fluid is studied using the Fourier expansion collocation method, within the framework of the linearized, three-dimensional theory of elasticity. The equations of motion of solid and fluid are respectively formulated using the constitutive equations of a transversely isotropic cylinder and the constitutive equation of an inviscid fluid. Three displacement potential functions are introduced to uncouple the equations of motion along the radial, circumferential and axial directions. The frequency equations of longitudinal and flexural (symmetric and antisymmetric) modes are analyzed numerically for an elliptic and cardioidal cross-sectional transversely isotropic solid cylinder of arbitrary cross-section immersed in fluid. The computed non-dimensional wavenumbers are presented in the form of dispersion curves for the material zinc. The general theory can be used to study any kind of cylinder with proper geometric relations. Crown Copyright © 2009.


Ponnusamy P.,Government Arts College Autonomous
Advances in Applied Mathematics and Mechanics | Year: 2015

In this paper, a mathematical model is developed to study the wave propagation in an infinite, homogeneous, transversely isotropic thermo-piezoelectric solid bar of circular cross-sections immersed in inviscid fluid. The present study is based on the use of the three-dimensional theory of elasticity. Three displacement potential functions are introduced to uncouple the equations of motion and the heat and electric conductions. The frequency equations are obtained for longitudinal and flexural modes of vibration and are studied based on Lord-Shulman, Green-Lindsay and Classical theory theories of thermo elasticity. The frequency equations of the coupled system consisting of cylinder and fluid are developed under the assumption of perfectslip boundary conditions at the fluid-solid interfaces, which are obtained for longitudinal and flexural modes of vibration and are studied numerically for PZT-4 material bar immersed in fluid. The computed non-dimensional frequencies are compared with Lord-Shulman, Green-Lindsay and Classical theory theories of thermo elasticity for longitudinal and flexural modes of vibrations. The dispersion curves are drawn for longitudinal and flexural modes of vibrations. Moreover, the dispersion of specific loss and damping factors are also analyzed for longitudinal and flexural modes of vibrations. © 2016 Global Science Press.


Ponnusamy P.,Government Arts College Autonomous | Rajagopal M.,Government Arts College Autonomous
JVC/Journal of Vibration and Control | Year: 2010

The problem of wave propagation in an infinite, homogeneous, transversely isotropic polygonal cross-sectional cylinder is studied using Fourier expansion collocation method, within the framework of linearized, three dimensional theory of thermoelasticity. Three displacement potential functions are introduced, to uncouple the equations of motion and the heat conduction. The frequency equations are obtained for longitudinal and flexural (symmetric and antisymmetric) modes of vibration and are studied numerically for triangular, square, pentagonal and hexagonal cross-sectional Zinc cylinders. To study the convergence, the non-dimensional wave numbers are obtained by Fourier Expansion Collocation Method and Finite Element Method and they are compared. The computed non-dimensional wave numbers are presented in the form of dispersion curves. © 2010 SAGE Publications Los Angeles, London, New Delhi, Singapore.


Ruby A.,Government Arts College Autonomous | Alfred Cecil Raj S.,St. Joseph's College
International Journal of ChemTech Research | Year: 2013

Optical quality single crystals of glycine thiourea (GT), a new organic nonlinear optical (NLO) crystal, were grown from aqueous solution by slow evaporation method. Solubility of GT was determined at various temperatures. Single crystal X-ray diffraction studies indicate that GT crystallizes in the monoclinic crystal system. Various diffracting planes of the grown crystal were identified from the powder X-ray diffraction study. The various functional groups of molecules present in GT were identified from FT-IR studies. The elemental analysis confirmed the stoichiometry of the compound. Optical characterization of the crystal shows the cut off wavelength near the UV region. Thermal stability and melting point of the grown crystal were found by thermal analyses. The powder second harmonic generation test of GT revealed its relative NLO efficiency is approximately 0.5 times that of potassium dihydrogen orthophosphate. The mechanical strength of the grown crystal is estimated by Vicker's hardness test.

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