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Datta A.,Manipal University India | Ray A.,Manipal University India | Bhattacharya G.,Ramakrishna Mission Vidyamandira | Saha H.,Jadavpur University
International Journal of Energy Sector Management | Year: 2011

Purpose: Reducing greenhouse gas emissions from fossil fuel consumption is a big challenge on the view of global warming and climate changes caused by greenhouse gases as per recent scientific reports. This paper aims to identify the major challenges of green energy sources (GES) to the future power systems and suggests an appropriate GES based on the preference by the decision maker on the various issues to meet these challenges. Design/methodology/approach: The proposed work presents a multi-criteria decision analysis (MCDA) - the analytic hierarchy process (AHP) to evaluate the GES - photovoltaic (PV), wind generator (WG), biomass (BM) and micro-hydel (MH) and to find the appropriate selection in general, by evaluating its main operational characteristic. In this research, the choices of the green energy alternatives on the basis of various factors have been taken into consideration. MATLAB simulation of different criteria to ascertain their clear-cut effects on GES selection under multiple uncertainties are presented. Findings: Related articles appearing in the recently published (1995-2010) works, based on green energy scope and practical implementations, and earlier approaches in the field of energy are gathered and analyzed so that the following questions can be answered: Which evaluating criteria are paid more attention to? Which source is the best GES? Which is the most critical factor in the green energy selection. This research not only provides the application of MCDA to evaluate the operation of the GES - PV, WG, BM and MH but also aids the researchers and decision makers in applying the approaches effectively. Originality/value: This is the first analysis in the green energy selection which considers future uncertainties of the GES. Instead of focusing only on cost factor, the proposed work considers main uncertainties of the GES. The best GES will be decided based on the preference of the criterion chosen by the end-user. © Emerald Group Publishing Limited.

Pal C.,Ramakrishna Mission Vidyamandira | Kshirsagar R.J.,Bhabha Atomic Research Center
Indian Journal of Physics | Year: 2010

The preliminary analysis of the DFT calculations and the high-resolution Fourier transform spectrum of the v 7 band of CD 3NO 2 have been carried out for the first time. The rotational structure up to J = 10 have been fitted using Watson's A-reduction in l' representation with a standard deviation of 0.0048cm -1. The rotational constants A, B, C have been obtained for the V 7 state of CD 3NO 2 with good statistical significance. © 2010 IACS.

Roy B.,Ramakrishna Mission Vidyamandira | Das S.,Saha Institute of Nuclear Physics
Journal of Alloys and Compounds | Year: 2011

We have investigated the effect of particle size on the electrical transport and magnetic properties of La 0.5A 0.5CoO 3 (A = Sr, Ca, and Ba) nanoparticles synthesized by sol-gel technique. A size-induced metal to insulator transition is observed in the resistivity behaviour of Sr- and Ba-doped samples as the dimension changes from higher to lower ones. The magnetoresistance exhibits almost linear behaviour throughout the studied field range. The zero-field-cooled (ZFC) and field-cooled (FC) magnetizations display a broad paramagnetic to ferromagnetic transition at T C with a large magnetic irreversibility. The magnetization results indicate that Co 3+ ions are in the intermediate spin state but Co 4+ ions stay in a mixture of intermediate and high spin states. The observed frequency dependent shoulder in the in-phase and the peak in the out of phase component of the ac susceptibility indicate the glassy nature of the samples. The analysis of the ac magnetization results suggests that the magnetic behaviour is consistent with the cluster glass model. © 2011 Elsevier B.V. All rights reserved.

Chakrabarti S.,Ramakrishna Mission Vidyamandira
European Journal of Physics | Year: 2015

We have performed an experiment in which we have determined the viscosity of air using the Hagen-Poiseuille equation in the proper range of the Reynolds number (Re). The experiment is novel and simple which students even at high school level can perform with minimal equipment.The experiment brings out the fact that determination of viscosity of a fluid is possible only when its Reynolds number is sufficiently small. At very large Reynolds number, the gas behaves more like an inviscid fluid and its flow rate satisfies Bernoulli's equation. In the intermediate range of the Reynolds number, the flow rate satisfies neither the Hagen-Poiseuille equation nor the Bernoulli equation. A wide range of Reynolds numbers from 40 to about 5000 has been studied. In the case of air, this large range has not shown any sign of turbulence. © 2015 IOP Publishing Ltd.

Gain S.,Ramakrishna Mission Vidyamandira | Das R.S.,Jadavpur University | Banerjee R.,Jadavpur University | Mukhopadhyay S.,Jadavpur University
Journal of Coordination Chemistry | Year: 2016

In aqueous acetate buffer, reaction between the superoxo complex [(dien)(en)CoIII(O2)CoIII(en)(dien)]5+ (1) and thiourea (Tu, SC(NH2)2) proceeds through a complex kinetic pathway and the change of the absorbance of 1 with time follows a sigmoidal trace. Only in the presence of Ellman’s reagent (5,5′-dithio-bis-(2-nitrobenzoic acid), DTNB), the reaction becomes quantitative and Tu reduces the bound superoxo group (– O- 2 –) of 1 to the corresponding peroxo group (– O2- 2 –) in [(dien)(en)CoIII(O2)CoIII(en)(dien)]4+ (2). In the presence of DTNB, with large excess of Tu over [1], the reaction follows first-order kinetics and the observed rate constant, ko, increases linearly with the increase in [1], [TTu] ([TTu] is the analytical concentration of Tu), [H+], and the media ionic strength (I). The presence of an intercept in the plot of ko versus [H+] suggests that both tautomeric forms of thiourea, i.e. TuZ and its protonated form TuZH+, are kinetically reactive reductants. The calculated rate constant values for k1 (~102) and k2 (~104) indicate that TuZH+ plays the leading role in the redox reaction. The present work also reveals the prospective involvement of Ellman’s reagent as a radical scavenger. © 2016 Informa UK Limited, trading as Taylor & Francis Group.

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