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S. N. Paul ¹, Vineet V. Karambelkar ¹, S. N. Rao ², J. D. Ekhe ³

Affiliations
1 Department of Metallurgical and Materials Engineering, Visvesvaraya National Institute of Technology, Nagpur - 440010, Maharashtra, IN
2 Department of Chemistry, Priyadarshini Institute of Engineering and Technology, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur - 400001, Maharashtra, IN
3 Department of Chemistry, Visvesvaraya National Institute of Technology, Nagpur - 440010, Maharashtra, IN

Abstract

Buckingham π theorem was applied to model polypyrrole synthesis done by inverse emulsion polymerization route using Methanesulfonic acid as a dopant and potassium persulfate as an oxidant. A list of independent parameters on which polymerization depends was selected and by means of Buckingham theorem a functional relation between three dimensionless quantities; percent yield, conductivity and temperature was obtained. The actual form of the function was determined on the basis of experimental analysis and linear regression analysis. The accuracy of the proposed application was scrutinized by synthesizing pristine polypyrrole salt by the said polymerization route. It was corroborated from the experiment that the increase in percent yield and conductivity was directly proportional to the increase in oxidant concentration. Conductivity as high as 3.77 S/cm was obtained with a maximum percent yield of 94.54% at a moderate temperature range (293 K-298 K).

Keywords

Buckingham Pi Theorem, Chemical Oxidative Polymerization, Dimensionless Quantities, Mathematical Modeling, Polypyrrole, Regression Analysis

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Vineet V. Karambelkar ¹, S. N. Paul ², J. D. Ekhe ¹

Affiliations
1 Department of Metallurgical and Materials Engineering, Visvesvaraya National Institute of Technology, Nagpur - 10, Maharashtra, IN
2 Department of Applied Chemistry, Visvesvaraya National Institute of Technology, Nagpur - 10, Maharashtra, IN

Abstract

Polypyrrole, an Intrinsically Conductive Polymer (ICP) was obtained through chemical oxidative polymerization of pyrrole and a low temperature sensing device was designed by pelletizing Ppy/Piezoceramic powder composite with Tin. Raw/Green pellets of Ppy/PZT composite were liquid phase sintered above the solidus temperature of Tin metal (2540C) to yield the final sensor. Current-Voltage (I-V) characteristics of two such sensor samples were analyzed. Sensor sample with 4 % Tin yielded maximum conductivity of 9.12 S/cm as compared with the sensor sample with 3 % Tin, conductivity dropped to 5 S/cm. Also, almost non- linear trend in the I-V curves was observed due to the environmental factors such as a small temperature range between 00C-1100C. Characterization of both the sensor samples using SEM confirmed that the sensor with higher Tin content behaved as a better sensor than the sensor having a lower Tin content.

Keywords

Conducting Polymers, Polypyrrole, PZT, Ppy/PZT Temperature Sensor, Sensor Design

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B. Ghosh ¹, S. N. Paul ¹, S. Bannerjee ², C. Das ³

Affiliations
1 Department of Physics, Jadavpur University, Kolkata-700032, IN
2 Department of Electronics, Vidyasagar College (Day), Kolkata, IN
3 Department of Physics, Uluberia College, Howrah, West Bengal, IN

Abstract

Theory of the generation of magnetic moment field from resonant interaction of three high frequency electromagnetic waves in un-magnetized dense electron plasma is developed including the relativistic change of electron mass. It is shown that the inclusion of relativistic effect enhances the magnetic moment field. For high intensity laser beams this moment field may be of the order of a few mega gauss. Such a high magnetic field can considerably affect the transport of electrons in fusion plasma.

Keywords

Inverse Faraday Effect, Resonant Excitation, Relativistic Effect.

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R. Bondyopadhaya ¹, S. N. Paul ¹, G. C. Pramanik ¹, Kalpana Bondyopadhaya ¹

Affiliations
1 Department of Mathematics, Jadavpur University, Calcutta-32, IN

Abstract

The hydromagnetic system of ionized gas is assumed to be present in the galactic nucleus. The wave propagation inside that medium has been investigated. It is found from the linearised tbeory that MHD wave may be unstable during its propagation through the nucleus of galaxy. It is suggested that the amplification of density wave may be one of the source of ejection of matter from the galactic nucleus and the damping of MHD wave may generate heat inside the nucleus of galaxy.

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