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Devaraja P.B.,Tumkur University | Devaraja P.B.,Rashtreeya Vidyalaya College of Engineering | Avadhani D.N.,Rashtreeya Vidyalaya College of Engineering | Prashantha S.C.,East West Institute of Technology | And 4 more authors.
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2014

Nanoparticles of magnesium oxide (MgO) have been prepared by low temperature solution combustion and hydrothermal method respectively. Powder X-ray diffraction (PXRD) patterns of MgO samples prepared by both the methods show cubic phase. The Scanning Electron Microscopy (SEM) studies reveal, the combustion derived product show highly porous, foamy and fluffy in nature than hydrothermally derived sample. The optical absorption studies of MgO show surface defects in the range 250-300 nm. The absorption peak at ∼290 nm might be due to F-centre. Photoluminescence (PL) studies were carried upon exciting at 290 nm. The sample prepared via combustion method show broad emission peak centred at ∼395 nm in the bluish-violet (3.14 eV) region. However, in hydrothermal prepared sample show the emission peaks at 395 and 475 nm. These emission peaks were due to surface defects present in the sample since nanoparticles exhibits large surface to volume ratio and quantum confinement effect. © 2013 Elsevier B.V. All rights reserved.


Shivram M.,Jawaharlal Nehru Technological University Anantapur | Prashantha S.C.,East West Institute of Technology | Nagabhushana H.,Tumkur University | Sharma S.C.,BMS College of Engineering | And 2 more authors.
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2014

Nanoparticles of Eu3+ doped (1-9 mol%) CaTiO3 were prepared using low temperature (500 C) solution combustion technique using metal nitrates as precursors and urea as fuel. The powder X-ray diffraction patterns of the as-formed products show single orthorhombic phase. The crystallite size was estimated using Scherrer's method and found to be in the range 40-45 nm. The effect of Eu3+ ions on luminescence characteristics of CaTiO 3 was studied and the results were discussed in detail. The phosphors exhibit bright red emission upon 398 nm excitation. The characteristic emission peaks recorded at ∼540, 593, 615, 653, 696 and 706 nm (5D 0 → 7Fj=0,1,2,3,4,5) were attributed to Eu3+ ions. The electronic transition corresponding to 5D0 → 7F2 (615 nm) was stronger than the magnetic dipole transition 5D0 → 7F1 of Eu3+ ions (596 nm). The CIE chromaticity co-ordinates were calculated from emission spectra, the values (x,y) very close to NTSC standard value of red emission. Therefore, the present phosphors were highly useful for display applications. © 2013 Elsevier B.V. All rights reserved.


Jnaneshwara D.M.,Tumkur University | Jnaneshwara D.M.,SJB Institute of Technology | Jnaneshwara D.M.,Rashtreeya Vidyalaya College of Engineering | Avadhani D.N.,Rashtreeya Vidyalaya College of Engineering | And 6 more authors.
Journal of Alloys and Compounds | Year: 2014

Zinc substituted cobalt ferrite powders {Co(1- x)ZnxFe2O4} (0.0 ≤ x ≤ 0.5) were prepared by the solution combustion method. The structural, morphological, magnetic and electrical properties of as synthesized samples were studied. Powder X-ray diffraction patterns reveals single phase, cubic spinel structure with space group No. Fd3̄m (2 2 7). As zinc concentration increases, the lattice constant increases and the crystallite size decreases. The minimum crystallite size of ∼12 nm was observed for x = 0.5 composition. The synthesized ferrite compounds show ferrimagnetic behavior, with coercivity value of 10779 Oe (Hard ferrite) at 20 K and 1298 Oe (soft ferrite) at room temperature (RT). The maximum saturation magnetization recorded for the Co 0.5Zn0.5Fe2O4 composition was 99.78 emu g-1 and 63.83 emu g-1 at 20 K and RT respectively. The dielectric parameters such as dielectric constant, loss tangent and AC conductivity were determined as a function of frequency at RT. The magnetic and dielectric properties of the samples illustrates that the materials were quite useful for the fabrication of nanoelectronic devices. © 2013 Elsevier B.V. All rights reserved.


Prashantha S.C.,East West Institute of Technology | Nagabhushana H.,Tumkur University | Sharma S.C.,BMS College of Engineering | Nagabhushana B.M.,M.S. Ramaiah Institute of Technology | And 2 more authors.
Sensors and Actuators, B: Chemical | Year: 2014

A simple and low-cost solution combustion method was used to prepare Eu3+ (1-11 mol%) doped Mg2SiO4 nanophosphors at 350 C using metal nitrates as precursors and ODH (Oxali di-hydrazide) as fuel. The final products were well characterized by powder X-ray diffraction (PXRD), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and UV-visible absorption (UV-Vis). The PXRD patterns of the as-formed products show single orthorhombic phase. The crystallite size was estimated using Scherrer's method and found to be in the range 20-25 nm. The effect of Eu3+ cations on the luminescence properties of Mg2SiO 4:Eu3+ nanoparticles were understood from the luminescence studies. The phosphors exhibit bright red emission upon 393 nm excitation. The characteristic emission peaks recorded at ∼577, 590, 612, 650 and 703 nm (5D0 → 7FJ=0,1,2,3,4) were attributed to the 4f-4f intra shell transitions of Eu3+ ions. The intensity of red emission was found to be related with the concentration of intrinsic defects, especially oxygen-vacancies, which could assist the energy transfer from the Mg2SiO4 host to the Eu3+ ions. The Commission International De I-Eclairage (CIE) chromaticity co-ordinates were calculated from emission spectra, the values (x,y) were very close to National Television System Committee (NTSC) standard value of red emission. Therefore, the present phosphor was highly useful for display applications. © 2014 Elsevier B.V.


Malleshappa J.,Tumkur University | Nagabhushana H.,Tumkur University | Prashantha S.C.,East West Institute of Technology | Sharma S.C.,Chhattisgarh Swami Vivekananda Technical University | And 3 more authors.
Journal of Alloys and Compounds | Year: 2014

The investigation involves preparation and photoluminescence properties of CeO2:Eu3+ (1-11 mol%) nano phosphors by eco-friendly green combustion route using Euphorbia tirucalli plant latex as fuel. The final product was characterized by powder X-ray diffraction (PXRD), Scanning electron microcopy (SEM) and Transmission electron microscopy (TEM). The PXRD and SEM results reveals cubic fluorite phase with flaky structure. The crystallite size obtained from TEM was found to be ∼20-25 nm, which was comparable to W-H plots and Scherrer's method. Photoluminescence (PL) emission of all the Eu 3+ doped samples shows characteristic bands arising from the transitions of 5D0 → 5FJ (J = 0, 1, 2, 3, 4) manifolds under excitation at 373 and 467 nm excitation. The 5D0 → 7F2 (613 nm) transition often dominate the emission spectra, indicating that the Eu3+ cations occupy a site without inversion center. The highest PL intensity was recorded for 9 mol% Eu3+ ions with 5 ml latex. PL quenching was observed upon further increase in Eu3+ concentration. The international commission on illumination (CIE) chromaticity co-ordinates were calculated from emission spectra, the values (x, y) were very close to national television system committee (NTSC) standard values of pure red emission. The results demonstrate that the synthesized phosphor material could be very useful for display applications. Further, the phosphor material prepared by this method was found to be non toxic, environmental friendly and could be a potential alternative to economical routes. © 2014 Elsevier Inc. All rights reserved.


Khader K.K.A.,Bharathidasan University | Sajith A.M.,Kannur University | Padusha M.S.A.,Bharathidasan University | Nagaswarupa H.P.,East West Institute of Technology | Muralidharan A.,Kannur University
New Journal of Chemistry | Year: 2014

Microwave-mediated, palladium catalyzed C-N bond forming reactions with activated cycloalkenyl nonaflates and enolizable heterocycles using cesium carbonate as a base and a catalytic system employing Pd(OAc)2/ Xantphos or Pd(OAc)2/dppp were found to be effective in driving the reactions to completion. This method resulted in good to excellent yields of the coupled products (22 examples, 25-90%) in short reaction time (30-60 min). Under optimum conditions, cycloalkenyl nonaflates were found to be an effective alternative to analogous triflates in C-N bond forming processes due to their increased stability under the reaction conditions. The use of tetrabutylammonium bromide (Bu4NBr) as an additive in these transformations proved to be effective and resulted in better yields of the coupled products. © 2014 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.


Sunil H.,Vemana Institute of Technology | Hiremath S.G.,East West Institute of Technology
Proceedings of the 2015 International Conference on Applied and Theoretical Computing and Communication Technology, iCATccT 2015 | Year: 2015

Medical images contain more data and therefore, to save the transmission time, storage capacity and saving the time, an efficient image compression method is required. In this work we introduce a new algorithm for image compression decompression (reconstruction) based on JPEG 2000 standards. The proposed algorithm is named as Decompression based composite splitting Algorithm (DBCA) which is the combination of the RLTA (Repetitive Loss-Thresholding algorithm) and DDA (Denoising Dividing Algorithm). In the first step of the proposed algorithm, the image is divided into sub-parts. These sub-parts of the image are treated as smaller size minimization problem. Each sub part of the image reconstructed individually and finally all the reconstructed parts of the image are combined together to get the reconstructed image. The visual and mathematical results are shown which are superior to the existing method for image compression and reconstruction. © 2015 IEEE.


Vikram S.,East West Institute of Technology | Jagadisha N.,East West Institute of Technology
Proceedings of 2014 IEEE International Conference on Advanced Communication, Control and Computing Technologies, ICACCCT 2014 | Year: 2015

Iris recognition is the widely used biometric analysis system which is used to precisely identify any individual by measuring the iris part of the eye. But in some circumstances iris image can't be captured completely which becomes unfit to perform some analysis and direct manipulations. Other aspects such as procurement process of iris data also come into considerations yielding insufficient results. In this paper we propose a probabilistic distribution method that analyse the edges and frontier and reconstructs unavailable regions of iris from Scidb (database used in this experiment) which includes all possible scenarios of capturing iris and other factors which affects the images and reconstructs to makes it fit for producing accurate results. Precisely, synthezing occupies and exhibits major contribution to emanate such demonstration. © 2014 IEEE.


Hemant P.,East West Institute of Technology | Pushpavathi T.,East West Institute of Technology
2012 3rd International Conference on Computing, Communication and Networking Technologies, ICCCNT 2012 | Year: 2012

Knowledge of incidence and prevalence of a disease is vital in Community Medicine to control a disease. It is important in Internal Medicine for clinical diagnosis and presumptive treatment on a probability model. Prevalence informs the total case load at a given time. Incidence yields a pointer to extent of attention required and choice of measures. Initially K-means clustering is used to group the disease related data into clusters and assigns classes to clusters. Subsequently multiple different classification algorithms are trained on the result set to build the final classifier model based on K-fold cross validation method. This methodology is evaluated using 768 raw diabetes data obtained from a city hospital. The best accuracy for the given dataset is achieved in bagging algorithm compared to other classifiers. The proposed approach helps doctors in their diagnosis decisions and also in their treatment planning procedures for different categories. © 2012 IEEE.


Prashantha S.C.,Bangalore University | Prashantha S.C.,East West Institute of Technology | Lakshminarasappa B.N.,Bangalore University | Singh F.,Inter University Accelerator Center
Journal of Luminescence | Year: 2012

Nanoparticles of Mg 2SiO 4:Eu 3 have been prepared by the solution combustion technique and the grain size estimated by PXRD is found to be in the range 40-50 nm. Ionoluminescence (IL) studies of Mg 2SiO 4:Eu 3 pellets bombarded with 100 MeV Si 8 ions with fluences in the range 1.124-22.48×10 12 ions cm -2 are carried out at IUAC, New Delhi, India. Five prominent IL bands with peaks at 580 nm, 590 nm, 612 nm, 655 nm and 705 nm are recorded. These characteristic emissions are attributed to the luminescence centers activated by Eu 3 cations. It is found that IL intensity decreases rapidly in the beginning. Later on, the intensity decreases slowly with further increase of ion fluence. The reduction in the ionoluminescence intensity with increase of ion fluence might be attributed to degradation of Si-O (ν 3) and Si-O (2ν 3) bonds present on the surface of the sample. The red emission with peak at 612 nm is due to characteristic emission of 5D 0→ 7F 2 of the Eu 3 cations. Thermoluminescence (TL) studies of Mg 2SiO 4:Eu 3 pellets bombarded with 100 MeV Si 8 cations with fluences in the range 5×10 11 ions cm -2 to 5×10 13 ions cm -2 are made at RT. Two prominent and well resolved TL glows with peaks at ∼220 °C and ∼370°C are observed. It is observed that TL intensity increases with increase of ion fluence. This might be due to creation of new traps during swift heavy ion irradiation. © 2012 Elsevier B.V. All rights reserved.

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