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Vellore District, India

Jeyasankar A.,Arignar Anna Government Arts College
Asian Pacific Journal of Tropical Disease | Year: 2012

Objective: To evaluate antifeedant, insecticidal and insect growth inhibitory activities of eucalyptus oil (Eucalyptus globules) and gaultheria oil (Gaultheria procumbens L.) against black cutworm, Agrotis ipsilon. Methods: Antifeedant, insecticidal and growth inhibitory activities of eucalyptus oil and gaultheria oil were tested against black cutworm, A. ipsilon. Results: Significant antifeedant activity was found in eucalyptus oil (96.24%) where as the highest insecticidal activity was noticed in gaultheria oil (86.92%). Percentages of deformities were highest on gaultheria oil treated larvae and percentage of adult emergence was deteriorated also by gaultheria oil. Conclusions: These plants oil has potential to serve as an alternative eco-friendly control of insect pest. © 2012 Asian Pacific Tropical Medicine Press.

Srinivasaraghavan R.,University | Chandiramouli R.,SASTRA University | Jeyaprakash B.G.,SASTRA University | Seshadri S.,Arignar Anna Government Arts College
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2013

The present work aims at understanding the structural stability of Cadmium oxide (CdO) nano-particles of different sizes due to its potential application in the field of optoelectronics and gas sensing. The stable structures of the (CdO)n (n = 1-8) have been fully optimized with Gaussian 03W program package at B3LYP/6-31G level, and it is found that, for n = 1-5, the ring structures is more stable, and for n > 5, the three-dimensional structures is more stable than the ring structure. But the stable ring geometries for n > 9 are found to be difficult, because the ring structures become more complicated. The present calculation also shows that, with the growth of the clusters, 3D structures are more favorable in energy, and the Cd and O atom tend to adopt higher coordination numbers. Moreover, the simulated IR spectra help to distinguish the ring structures from the cubic or hexagonal packing structures. © 2012 Elsevier B.V. All rights reserved.

Mahalakshmi G.,Karpagam University | 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 3,3′-bis (trifluoromethyl) benzophenone (TFMBP) were recorded and analyzed. Natural bond orbital analysis on TFMBP, 3,3′-bis (trichloromethyl) benzophenone (TCMBP) and 3,3′-bis (tribromomethyl) benzophenone (TBMBP) has been carried out for various intramolecular interactions that are responsible for the stabilization of the molecule. HOMO-LUMO energy gap of the halogen substitution (Cl, Br) has been computed with the help of density functional theory. The statistical thermodynamic functions (heat capacity, entropy, vibrational partition function and Gibbs energy) were obtained for the range of temperature 100-1000 K. The polarizability, first hyperpolarizability, anisotropy polarizability invariant has been computed using quantum chemical calculations. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of the experimental and theoretical spectra values provides important information about the ability of the computational method to describe the vibrational modes. UV-VIS spectral analyses of TFMBP have been researched by theoretical calculations. In order to understand electronic transitions of the compound, TD-DFT calculations on electronic absorption spectra in gas phase and solvent (DMSO and Chloroform) were performed. The calculated frontier orbital energies, absorption wavelengths (λ), oscillator strengths () and excitation energies (E) for gas phase and solvent (water and methanol) are also illustrated. Crown Copyright © 2014 Published by Elsevier Ltd. All rights reserved.

Bangaru S.,Arignar Anna Government Arts College | Muralidharan G.,Gandhigram Rural University
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2010

This paper reports thermoluminescence (TL) glow and emission, optical absorption and optically stimulated emission studies made on Ce3+ doped KBr single crystals irradiated at room temperature. Optical absorption and photoluminescence studies confirm the presence of cerium ions in the trivalent state. A broad and intense blue emission around at 290 and 390 nm, attributable to the transition from 5d excited state to the 4f1 ground state of Ce3+ ions could be observed in the photoluminescence emission. Two TL glow peaks were observed at 374 and 422 K. Presence of characteristic emission due to Ce3+ ions in the optically stimulated emission at the F-band confirms the participations of the Ce3+ ions in the defect production and recombination processes. © 2010 Elsevier B.V. All rights reserved.

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.

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