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Kanagathara N.,Vel Technology Multi Technology Dr Rangarajan Dr Sakunthala Engg College | Marchewka M.K.,Institute of Low Temperature And Structure Research | Drozd M.,Institute of Low Temperature And Structure Research | Renganathan N.G.,Vel Tech Dr.RR & Dr.SR Technical University | And 2 more authors.
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2013

Melaminium perchlorate monohydrate (MPM), an organic material has been synthesized by slow solvent evaporation method at room temperature. Powder X-ray diffraction analysis confirms that MPM crystal belongs to triclinic system with space group P-1. FTIR and FT Raman spectra are recorded at room temperature. Functional group assignment has been made for the melaminium cations and perchlorate anions. Vibrational spectra have also been discussed on the basis of quantum chemical density functional theory (DFT) calculations using Firefly (PC GAMESS) version 7.1 G. Vibrational frequencies are calculated and scaled values are compared with experimental values. The assignment of the bands has been made on the basis of the calculated PED. The Mulliken charges, HOMO-LUMO orbital energies are analyzed directly from Firefly programlog files and graphically illustrated. HOMO-LUMO energy gap and other related molecular properties are also calculated. The theoretically constructed FT-IR and FT-Raman spectra of MPM coincidewith the experimental one. The chemical structure of the compound has been established by 1H and 13CNMRspectra. No detectable signal was observed during powder test for second harmonic generation. © 2013 Elsevier B.V. All rights reserved.


Kanagathara N.,Vel Technology Multi Technology Dr Rangarajan Dr Sakunthala Engg College | Marchewka M.K.,Institute of Low Temperature And Structure Research | Drozd M.,Institute of Low Temperature And Structure Research | Renganathan N.G.,Vel Tech Dr.RR & Dr.SR Technical University | And 2 more authors.
Journal of Molecular Structure | Year: 2013

An organic-organic salt, bis (4-nitrophenol) 2,4,6-triamino 1,3,5-triazine monohydrate (BNPM) has been prepared by slow evaporation technique at room temperature. Single crystal X-ray diffraction analysis reveals that the compound crystallizes in triclinic system with centrosymmetric space group P-1. IR and Raman spectra of BNPM have been recorded and analyzed. The study has been extended to confocal Raman spectral analysis. Band assignments have been made for the melamine and p-nitrophenol molecules. Vibrational spectra have also been discussed on the basis of quantum chemical density functional theory calculations using Firefly (PC GAMESS) Version 7.1 G. Vibrational frequencies are calculated and scaled values are compared with the experimental one. The Mulliken charges, HOMO-LUMO orbital energies are calculated and analyzed. The chemical structure of the compound was established by 1H NMR and 13C NMR spectra. © 2013 Elsevier Ltd. All rights reserved.


Kanagathara N.,Vel Technology Multi Technology Dr Rangarajan Dr Sakunthala Engg College | Sivakumar N.,Presidency College at Chennai | Gayathri K.,Presidency College at Chennai | Krishnan P.,Presidency College at Chennai | And 3 more authors.
Proceedings of the Indian National Science Academy | Year: 2013

Single crystals of 2,4,6 triamino-1,3,5 triazine (melamine) have been grown successfully by slow evaporation solution growth technique at room temperature. Single crystal X-ray diffraction studies reveals that the crystal crystallizes in monoclinic system P21/c with lattice parameters a = 7.29Å, b = 7.48Å, c = 10.33Å, α= 90°, β = 108.52°, γ = 90° and V = 534(Å)3. The functional groups have been identified by FTIR spectral analysis. The chemical structure of the compound was established by FT-NMR technique. The thermal stability and decomposition of the crystal were studied by thermo gravimetric analysis and it was found that the material was thermally stable up to 336°C. The NLO property was confirmed by Kurtz and Perry powder technique. © Printed in India.


Muthukumar S.,Vel Technology Multi Technology Dr Rangarajan Dr Sakunthala Engg College | Mathiyalagan P.,Vel Tech Dr.RR & Dr.SR Technical University | Mariappan R.,Vel Tech Dr.RR & Dr.SR Technical University | Jayavelu S.,Vel Tech Dr.RR & Dr.SR Technical University
International Journal of Vehicle Structures and Systems | Year: 2014

In this work, the dry sliding wear behaviour and friction characteristics of aluminium alloy Al6061 silicon carbide particulates (SiCp) of size 43 μm reinforced composites were evaluated through laboratory experiments. The content of SiCp in the alloy was varied from 5% to 35% in steps of 5% by weight. The metal matrix composites were manufactured using stir casting technique. A pin-on-disc wear testing machine was used to evaluate the wear rate, in which an EN-31 steel disc was used as a counter face. Results indicated that the wear rates of the composites were lower than that of the matrix alloy and further reduction in wear rate was achieved by increasing the SiCp content. The wear rate increased for an increase in the load and sliding velocity. Increase in the applied load increased the wear severity by changing the wear mechanism from abrasion to particle cracking. The observations have been explained using scanning electron microscopy analysis of the worn surfaces. The coefficient of friction was evaluated using friction forces measured from the tests. The coefficient of friction decreased for an increase in the SiCp content at low sliding velocity. © 2014. MechAero Foundation for Technical Research & Education Excellence.


Gayathri K.,Presidency College at Chennai | Krishnan P.,Presidency College at Chennai | Kanagathara N.,Vel Technology Multi Technology Dr Rangarajan Dr Sakunthala Engg College | Anbalagan G.,Presidency College at Chennai
Journal of Applied Spectroscopy | Year: 2013

Brucinium hydrogen (S) malate pentahydrate (BH(S)M), an organic compound, has been synthesized, and BH(S)M single crystals were grown from an ethanol/water solution by slow evaporation of the solvent at room temperature up to dimensions of 15 × 4 × 2 mm3. Single-crystal X-ray diffraction study shows that they belong to a triclinic system (a = 9.342 Å, b = 9.510 Å, c = 16.874 Å, a = 76.61°, b = 89.14°, and g = 81.79o) in a non-centrosymmetric space group P1. Fourier transform infrared (FTIR) spectroscopic study was performed to identify different modes of functional groups present in the compound. The UV-Vis-NIR transmission spectrum has been recorded in a range of 200-1100 nm. It exhibits maximum transparency (87%) in the 425-650 nm range, suggesting the suitability of the title compound for optical applications. The thermal stability of the compound has been determined by TG-DTA curves. Microhardness tests have been performed on the crystal under study, and the Vickers hardness number has been calculated. The work hardening coefficient is found to be 4.2, which suggests that the crystal belongs to the family of soft materials. The SHG efficiency of the crystal was evaluated by the Kurtz powder technique using a Nd:YAG pulsed laser. © 2013 Springer Science+Business Media New York.

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