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Raj K.P.,Bharathiar University | Sadayandi K.,Alagappa Government Arts College
Physica B: Condensed Matter | Year: 2016

This present study brings the synthesis of Zinc oxide (ZnO) nanoparticles (NPs) by the standard aqueous chemical route technique. The impact of calcination temperature on the extent of the ZnO nanoparticles is studied for its lattice constraints. X-ray diffraction (XRD) affirms the hexagonal Wurtzite structure of the synthesized ZnO nanoparticles. From the Williamson-Hall (W-H) plot, positive slope is inferred for pure and calcined ZnO NPs and confirms the presence of tensile strain. From the SEM images it is found that the crystallinity enhances with calcination temperature. From the optical studies, it is found that the band gap energy decreases with improved transmission. The Photoluminescence (PL) spectrum reveals the UV emission is strong near the band-edge. The emission peaks around 400-480 nm result in blue emission and the peaks around 540-560 nm result in green emission. Decrease in band gap energy and enhancement in PL studies reveal the red shift of the calcined ZnO exhibiting solid quantum confinements. © 2016 Elsevier B.V. All rights reserved.

Udayaganesan P.,Alagappa Government Arts College | Angusamy N.,Fortesque Metals Group | Gujar A.R.,National Institute of Oceanography of India | Rajamanickam G.V.,Sri Sairam Group of Institutions
Journal of the Geological Society of India | Year: 2011

Quartz grain surface micro textures of 12 samples collected from the beach were examined under scanning electron microscopy to understand the role of coastal processes on their transportation and deposition. The study area has been divided into three sectors on the basis of drainage, geomorphology and nature of the beach and shelf topography. Surface textures of the northern sector display an array of mechanical features like conchoidal fracture, V marks and impact pits, indicating the dominance of mechanical processes. However, silica precipitation in the form of globules indicates an added influence of chemical processes in the Northern sector. The presence of chemical features in northern sector, where energy level is high, corroborates the addition of quartz grains from paleo-sediments, from the nearby Tertiary and Cretaceous formations. Central sector quartz grains display the signatures of chemical and mechanical processes. The presence of step like furrows in southern sector is an indicator of fluvial low energy conditions, and supplements the role of littoral currents in depositing the quartz grains along the coastal region. © 2011 Geological Society of India.

Manohar A.,Kalasalingam University | Ramalingam K.,Annamalai University | Karpagavel K.,Kalasalingam University | Kulandaisamy A.,Alagappa Government Arts College
International Journal of ChemTech Research | Year: 2012

[Cd(deadtc)2]2 (1), [Cd(deadtc)2(2,2'-bipy)] (2), [Cd(deadtc)2(1,10-phen))] (3), [Cd2(deadtc)4(4,4'- bipy)] (4), [Cd(deadtc)2(TMED)] (5) and [Cd(deadtc)2(py)] (6) (deadtc- = di(2-hydroxyethyl)dithiocarbamate anion, 2,2'-bipy = 2,2'-bipyridine, 4,4'-bipy = 4,4'-bipyridine, 1,10-phen = 1,10-phenanthroline, TMED = Tetramethylethylenediamine, py = pyridine) have been synthesized and characterized by IR and electronic spectroscopy, elemental analysis and thermogravimetry. IR spectra of the complexes show that the thioureide (νC-N) band values are lower than the values observed for the parent dithiocarbamate. A reduction in the thioureide stretching frequency is due to the increase in coordination around the cadmium ion and the resultant increase in electron density. Thermal studies indicate that 1,10-phenanthroline adduct is more stable than other adducts. The charge transfer transitions are observed in the region 310 - 340 nm. Bond valence sum (BVS) values close to 2.00 in all the cadmium complexes support the correctness of the crystal structures.

Meenakshi M.,Alagappa Government Arts College | Sivakumar R.,Alagappa University | Perumal P.,Alagappa Government Arts College | Sanjeeviraja C.,Alagappa Chettiar College of Engineering And Technology
Materials Today: Proceedings | Year: 2016

Among the transition metal oxides, Tungsten Oxide (WO3) is the most widely used electrochromic material for smart window applications. Tungsten oxide thin films can be modified by mixing V2O5 in various proportions to achieve neutral coloring. In the present work, influence on structural, optical, surface morphological and electrochromic properties by mixing of V2O5 with WO3 has been studied. V2O5 mixed WO3 targets of various compositions were prepared and homogeneity of those targets was confirmed through powder X-ray diffraction. Thin films were prepared by RF magnetron sputtering method using Corning glass as substrates with 100 W as RF power at room temperature. The as-deposited films were found as amorphous with good adhesion to the substrate. Laser Raman studies confirmed this amorphous nature. Neutral coloration was achieved with low amount of mixing of V2O5 with WO3. Room temperature photoluminescence characterizations revealed the presence of strong emissions in the near UV (375 nm) and blue (418 nm) regions when excited at 275 nm. Electrochemical cation intercalation was promoted using 0.05 M H2SO4. Electrochromic parameters such as response time, diffusion constants, reversibility and coloration efficiency were calculated from the electrochromical and iono-optical studies like chronoamperometry and chronocoulometry. © 2016 The Authors.

Santhi K.,Alagappa Government Arts College | Rani C.,Alagappa Government Arts College | Karuppuchamy S.,Alagappa University
Journal of Alloys and Compounds | Year: 2016

Nanostructured SnO/SnO2 hybrid material was successfully synthesized by microwave irradiation method. X-ray diffraction spectroscopy shows the formation of SnO/SnO2 nanocomposite material. Nanosphere morphology of the nanocomposite was observed by scanning electron microscopy. UV-visible diffuse reflectance spectra demonstrate that the light absorption capacity of SnO/SnO2 nanocomposite was extended to the visible region. The photocatalytic activity of SnO/SnO2 nanocomposite was investigated by the degradation of methylene blue under UV light irradiation. The effect of SnO/SnO2 nanocomposite dose, dye concentration, pH and irradiation time for photodegradation of methylene blue dye was also studied. SnO/SnO2 nanocomposite exhibits higher photocatalytic activity in neutral pH. © 2015 Elsevier B.V. All rights reserved.

Santhi K.,Alagappa Government Arts College | Rani C.,Alagappa Government Arts College | Karuppuchamy S.,Alagappa University
Journal of Materials Science: Materials in Electronics | Year: 2016

Ni doped WO3 and NiWO4 nanomaterials were successfully synthesized by microwave irradiation method. The synthesized nanomaterials were characterized using advanced techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy and UV–visible spectroscopy. XRD pattern shows the formation of orthorhombic phase for as-synthesized Ni doped WO3 and monoclinic phase for the calcined samples (NiWO4), respectively. The nanosphere morphology of Ni doped WO3 and NiWO4 samples were confirmed by SEM. The Alizarin Red S dye was successfully degraded using Ni doped WO3 and NiWO4 nanomaterials. The effects of pH and irradiation time on degradation of Alizarin Red S dye solution were also investigated. The maximum dye degradation efficiency of 77 % was achieved by Ni doped WO3. © 2016 Springer Science+Business Media New York

Vasanthi R.,Alagappa Chettiar College of Engineering And Technology | Subramanian K.,Alagappa Government Arts College
Scientific World Journal | Year: 2016

A simple graph G=(V,E) is said to be r-regular if each vertex of G is of degree r. The vertex covering transversal domination number γvct(G) is the minimum cardinality among all vertex covering transversal dominating sets of G. In this paper, we analyse this parameter on different kinds of regular graphs especially for Qn and H3,n. Also we provide an upper bound for γvct of a connected cubic graph of order n≥8. Then we try to provide a more stronger relationship between γ and γvct. © 2016 R. Vasanthi and K. Subramanian.

Gowthami V.,Alagappa Government Arts College | Perumal P.,Alagappa Government Arts College | Sivakumar R.,Alagappa University | Sanjeeviraja C.,Alagappa Chettiar College of Engineering And Technology
Physica B: Condensed Matter | Year: 2014

In the present work, nickel oxide thin film has been deposited on glass substrates at temperature 400 °C by simple and inexpensive nebulizer spray technique. The effect of the volume of sprayed solution on structural and optical properties of the films were investigated using X-ray diffractometer, UV-Vis-NIR spectrometer, photoluminescence, Raman spectrum and linear four probe resistivity measurement, respectively. It is found that increase in the sprayed volume of solution with 0.3 M leads to increase in the film thickness. XRD studies indicated cubic structure and the crystallites are preferentially oriented along the [1 1 1] direction. It is also found that as the sprayed volume of the solution increases the transmittance decreases, consequently the band edge shifted from lower wavelength to higher wavelength and the band-gap energy wanes from 3.64 eV to 3.13 eV. From PL spectra, the sample shows sharp and strong UV emission around 376 nm corresponding to the near bandedge emission of NiO under excitation of 275 nm. © 2014 Elsevier B.V.

Murugan S.,Alagappa Government Arts College
Proceedings of the 2013 International Conference on Pattern Recognition, Informatics and Mobile Engineering, PRIME 2013 | Year: 2013

Forecasting based on time series data for stock prices, currency exchange rate, price indices, etc., is one of the active research areas in many field viz., finance, mathematics, physics, machine learning, etc. Initially, the problem of financial time sequences analysis and prediction are solved by many statistical models. During the past few decades, a large number of neural network models have been proposed to solve the problem of financial data and to obtain accurate prediction result. The statistical model integrated with ANN (Hybrid model) has given better result than using single model. This work discusses some basic ideas of time series data, need of ANN, importance of stock indices, survey of the previous works and it investigates neural network models for time series in forecasting. The forecasting accuracy is analyzed and measured with reference to an Indian stock market index such as Bombay Stock Exchange (BSE) and NIFTY MIDCAP50 in this study and it is found that the right parameters number of epochs, learning rate and momentum is 2960, 0.28 and 0.5 respectively for forecasting network by conducting various experiment. © 2013 IEEE.

Murugan S.,Alagappa Government Arts College
Proceedings - 2014 World Congress on Computing and Communication Technologies, WCCCT 2014 | Year: 2014

This paper investigates the various training algorithm with Multi-Layer Perceptron Feed Forward Neural Network (MLPFFNN) and identify the best training algorithm for Indian Stock Exchange Market especially for BSE100 and NIFTY MIDCAP50. The forecasting accuracy is analyzed and measured with reference to an Indian stock market index such as Bombay Stock Exchange (BSE) and NIFTY MIDCAP50 in this study and it is found that the best training algorithm is Levenberg-Marquardt. All Training algorithms uses the 1-5-1 MLPFFNN architecture and its various parameter such as epochs, learning rate, etc are studied and the results are tabulated for the data division ratio 60%, 20% and 20% which represents training, validating and testing for all training algorithm. © 2014 IEEE.

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