Time filter

Source Type

Srivastava H.M.,University of Victoria | Lokesha V.,Acharya Institute of Technology | Wu Y.-D.,Zhejiang Xinchang High School
Computers and Mathematics with Applications | Year: 2011

In this paper, the authors give a new refinement of the JanousGmeiner inequality for a triangle by making use of certain analytical techniques for systems of nonlinear algebraic equations. Some other closely-related geometric inequalities are also considered. © 2011 Elsevier Ltd. 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.


Brugnago R.J.,Federal University of Paraná | Satyanarayana K.G.,Acharya Institute of Technology | Satyanarayana K.G.,BMS College of Engineering | Wypych F.,Federal University of Paraná | Ramos L.P.,Federal University of Paraná
Composites Part A: Applied Science and Manufacturing | Year: 2011

This paper describes a pretreatment option to sugarcane bagasse fibers for their use in composite preparation with unsaturated polyester. Sugarcane bagasse fibers modified by (i) steam explosion and (ii) alkali washing after steam explosion, along with (iii) as-received bagasse fibers were characterized. Steam explosion significantly reduced the amount of hemicelluloses and acid-soluble lignin of bagasse fibers, while acid-insoluble lignin increased proportionally. Alkaline washing of steam-exploded fibers removed nearly 60% of their acid-insoluble lignin. Polyester matrix composites containing 10 wt.% of these fibers were prepared by compression molding. Density, thermal stability, water absorption and thermomechanical analysis of the composites containing steam explosion treated bagasse fibers showed improvement in these properties over those of the untreated fiber containing composite. These are explained in terms of the chemical modifications that occurred due to the steam explosion treatments. © 2010 Elsevier Ltd. All rights reserved.


Premkumar H.B.,Acharya Institute of Technology | Premkumar H.B.,Tumkur University | Nagabhushana H.,Tumkur University | Sharma S.C.,Chattisgarh Swamy Vivekananda Technological University | And 4 more authors.
Journal of Alloys and Compounds | Year: 2014

A series of Eu3+ (1-6 mol%) activated YAlO3 nanophosphors have been synthesized by a low temperature solution combustion method using ODH fuel. The structural, morphological, thermo and photoluminescent properties are studied. Powder X-ray diffraction patterns indicate that the phosphors are orthorhombic phase of YAlO3 with small traces of Y3Al5O12 phase. Scanning Electron micrographs show the crystallites are fused together to form dumbbell shape. Transmission Electron micrograph shows the crystallites are nano size in the range 30-45 nm. Photoluminescence studies of Eu doped YAlO3 showed orange red emission (CIE co-ordinates x = 0.645, y = 0.353) due to the 5D0→7Fj (j = 0, 1, 2, 3, 4) transitions of Eu3+ ions. The concentration quenching occurs at x = 5 mol%. YAlO3:Eu3+ (5 mol%) exhibit two thermoluminescence (TL) glow peaks around 229 and 324 C respectively. TL response with different γ-doses show a good linear response and low fading suggesting that Eu 3+ activated YAlO3 is suitable for radiation dosimetry applications. The kinetic parameters (E, b, s) are estimated using peak shape method and discussed in detail. © 2014 Elsevier B.V. All rights reserved.


Simsek Y.,Akdeniz University | Bayad A.,DeVry University | Lokesha V.,Acharya Institute of Technology
Mathematical Methods in the Applied Sciences | Year: 2012

The aim of this paper was to derive new identities and relations associated with the q-Bernstein polynomials, q-Frobenius-Euler polynomials, l-functions, and q-Stirling numbers of the second kind. We also give some applications related to theses polynomials and numbers. Copyright © 2012 John Wiley & Sons, Ltd.


Maharana S.K.,Acharya Institute of Technology
12th Americas Conference on Wind Engineering 2013, ACWE 2013: Wind Effects on Structures, Communities, and Energy Generation | Year: 2013

The wind flow over several prismatic buildings lying in close vicinity in urban areas generates flow interference effects causing problems related to pollution, pedestrian comfort and ventilation within the buildings thus promoting a lot of research interest in this area during the last few years. A prismatic building together with a sloping roof structure is usually found in most part of India. There is an interference effect felt in the wind flow in this situation mentioned above. The interference effects are well supported by the understanding of wake of building models in some arrangements. The wake and its characteristics of a building has drawn attention for various applications like dispersion of pollutants downwind of conventional or nuclear power plants, airport runway interference effect, take-off/landing limitation at heliports, pedestrian wind comfort, and wind loads on structures. Computational Fluid dynamics (CFD) is one of the promising technologies for investigating these important issues which will not necessarily be solved by traditional wind tunnel technology. Through CFD the part of the project is to validate different physical phenomena arising out of wind flow over a single building model and then attempt to study the same or similar situation when a sloping roof structure is placed in tandem. After an attempt to numerically compute the flow parameters over a single 3D building model the focus has shifted towards looking at vortex shedding downstream of building in the wake zone to gain an insight into the low pressure region through a energy exchange activity between the flow and the vorticity being shed from solid walls.


Sadashiv N.,Acharya Institute of Technology | Kumar S.M.D.,University Visvesvaraya College of Engineering
ICCSE 2011 - 6th International Conference on Computer Science and Education, Final Program and Proceedings | Year: 2011

Cloud computing is rapidly growing as an alternative to conventional computing. However, it is based on models like cluster computing, distributed computing, utility computing and grid computing in general. This paper presents an end-to-end comparison between Cluster Computing, Grid Computing and Cloud Computing, along with the challenges they face. This could help in better understanding these models and to know how they differ from its related concepts, all in one go. It also discusses the ongoing projects and different applications that use these computing models as a platform for execution. An insight into some of the tools which can be used in the three computing models to design and develop applications is given. This could help in bringing out the innovative ideas in the field and can be explored to the needs in the computing world. © 2011 IEEE.


Shareef M.I.,Acharya Institute of Technology | Leelavathi S.,University of Mysore
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2011

The ethanolic extracts of the various parts of the plants namely Anisolmeles malabarica R.Br. (Lamiaceae) and Clerodendrum serratum L. (Verbenaceae) were investigated for their Antioxidant efficacy by DPPH and Nitric Oxide assay. Reactive Oxygen Species (ROS) and many of the free radicals are natural by-products of metabolism of drugs, environmental chemicals and other Xenobiotics as well as endogenous chemicals, especially stress hormones like adrenalin and noradrenalin. ROS has a high reactive potential and is responsible for many of the human diseases like diabetes, cancer, viral infections, cardiovascular diseases and inflammations and is known to cause oxidative damage to DNA, proteins and lipids in humans. The antioxidants present in the medicinal plants quench the free radicals by donating a hydrogen atom. The antioxidant activity of the medicinal plants namely, Anisolmeles malabarica and Clerodendrum serratum was estimated by using 2, 2-diphenyl-picryl-hydrazyl (DPPH) and Nitric Oxide assays. The present study aims at evaluating therapeutic potential of these medicinal plants due to their high free radical scavenging activity.


Kempraj V.,33rd Cross | Bhat S.K.,Acharya Institute of Technology
Pesticide Biochemistry and Physiology | Year: 2011

The current study involved evaluation of the toxicity of acetone soluble fraction of the ethanol extract of Annona squamosa Linn. seeds on Aedes albopictus (Skuse). Toxicity of fresh sample has been compared with that of solar radiated and heat treated aliquots of the same. Acute toxicity of fresh acetone fraction on adults was evident with LC50 and LC90 values of 15.21 and 60.38μg/ml, respectively. Larvicidal bioassays recorded LC50 and LC90 values ranging from 0.44 to 5.97 and 1.64-43.36μg/ml, respectively for different instars. Ovicidal bioassays yielded EC50 and EC90 values of 18.82 and 69.61μg/ml. The study further revealed ovipositional deterrent and chemosterilant activities of the extract on the target mosquito. Bioassays using solar radiation and heat treated samples of the active fraction have showed toxicity levels similar to those of fresh sample. Chemical analysis of acetone soluble fraction of seed extract of A. squamosa has reveled ethyl oleate and iso-octyl phthalate as major components. Adulticidal, larvicidal, ovicidal, ovipositional deterrent and chemosterilant activities of the fraction on A. albopictus were proved. The investigation further confirmed stability of the active fraction on exposure to solar radiation and high temperature. © 2011 Elsevier Inc.


Pillai V.V.,Acharya Institute of Technology | Sreekanth B.,Acharya Institute of Technology
International Journal of Pharma and Bio Sciences | Year: 2013

The two new complexes Ag(L1)2L2(PF6)2[Complex (1) and Cu(L1)2L2(PF6)2[Complex (2)] containing bioactive mixed ligand of typeL1=8-Hydroxyquinoline and L2=1,10-Phenanthroline have been synthesized and characterized by analytical and spectral methods. The binding constant of the complexes in 5 mM Tris-HCl/50 mM NaCl buffer at pH 7.2, are 25.79 x 106 M-1and 9.95 x 106 M-1for complex (1) and (2) respectively. The synthesized compounds have been tested against microorganisms such as Gram positive bacteria (Staphylococcus aureus and Proteus vulgaris), Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and fungus (Aspergillus niger). A comparative study of the Minimum Inhibitory Concentration(MIC) values of the ligands and their complexes indicates that the complexes exhibit moderate antimicrobial activity than the free ligand and control.

Loading Acharya Institute of Technology collaborators
Loading Acharya Institute of Technology collaborators