Midnapore College Autonomous

Medinīpur, India

Midnapore College Autonomous

Medinīpur, India
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Bag S.,Sambalpur University | Das P.,Midnapore College Autonomous | Behera B.,Sambalpur University
Journal of Theoretical and Applied Physics | Year: 2017

The ac impedance and conductivity properties of Dy doped Bi4V2 − xDyxO11 (x = 0.05, 0.10, 0.15 and 0.20) ceramics prepared by solid-state reaction technique, in a wide frequency range at different temperatures have been studied. All the samples exhibited β-type phase orthorhombic structure at room temperature. The Nyquist plot confirmed the presence of both grain and grain boundary effects for all Dy doped samples. Double relaxation behavior was also observed. The grain and grain boundary resistance decreases with rise in temperature for all the concentration and exhibits a typical negative temperature co-efficient of resistance (NTCR) behavior. An analysis of the electric modulus suggests the possible hopping mechanism for electrical transport processes of all the materials. The ac conductivity spectrum obeys Jonscher’s universal power law. DC conductivity of the materials were also studied and values of the activation energy found to be 0.40, 0.49, 0.73 and 0.78 eV for the compositions x = 0.05, 0.10, 0.15 and 0.20, respectively, at different temperatures (150–375 °C). © 2017, The Author(s).


Kolya H.,Midnapore College Autonomous | Pal S.,Indian School of Mines | Pandey A.,Midnapore College Autonomous | Tripathy T.,Midnapore College Autonomous
European Polymer Journal | Year: 2015

Sodium alginate-g-poly-(N,N-dimethylacrylamide-co-acrylic acid) was prepared in presence of potassium peroxydisulfate (K2S2O8) as the initiator by solution polymerization technique. The so prepare graft copolymer was characterized by different characterization techniques like determination of molecular weight by SEC, FTIR, 1H NMR and 13C NMR spectroscopy, XRD-studies. Biodegradation of the graft copolymer was analyzed by enzymatic cleavage. The graft copolymer was used to synthesize gold nanoparticles from chloroauric acid tetra hydrate (HAuCl4, 4H2O) without addition of any reducing agent. The gold nanoparticles were characterized by UV-VIS spectroscopy, Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray Analysis (EDAX). The effects of various synthetic parameters such as polymer and chloroauric acid (HAuCl4, 4H2O) concentration, pH, reaction time and temperature were studied for finding optimum condition. It was shown that the synthesized nanoparticles were rice shaped. One type of synthesized gold nanoparticles, under optimized condition was used for antimicrobial activity against both gram-negative and gram-positive bacteria by agar well diffusion method. The gold nanoparticles prepared under optimum condition exhibits excellent anti bacterial sensitivity to one gram negative bacteria Vibrio parahaemolyticus (ATCC-17802) and one gram positive bacteria Bacillus subtilis (ATCC-11774). © 2015 Elsevier Ltd. All rights reserved.


de S.K.,Midnapore College Autonomous | Sana S.S.,Bhangar Mahavidyalaya
Journal of Intelligent Manufacturing | Year: 2016

This paper investigates a hill type economic production-inventory quantity (EPIQ) model with variable lead-time, order size and reorder point for uncertain demand. The average expected cost function is formulated by trading off costs of lead-time, inventory, lost sale and partial backordering. Due to the nature of the demand function, the frequent peak (maximum) and valley (minimum) of the expected cost function occur within a specific range of lead time. The aim of this paper is to search the lowest valley of all the valley points (minimum objective values) under fuzzy stochastic demand rate. We consider Intuitionistic fuzzy sets for the parameters and used Intuitionistic Fuzzy Aggregation Bonferroni mean for the defuzzification of the hill type EPIQ model. Finally, numerical examples and graphical illustrations are made to justify the model. © 2016 Springer Science+Business Media New York


PubMed | Sidho Kanho Birsha University and Midnapore College Autonomous
Type: | Journal: International journal of biological macromolecules | Year: 2017

Amylopectin-g-poly (acrylamide-co-acrylic acid) [AP-g-poly (AM-co-AA)] was synthesised in water medium by using potassium perdisulphate as an initiator. The graft copolymer was characterized by molecular weight determination by size exclusion chromatography (SEC), fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy, scanning electron microscope (SEM) studies, thermal analysis, measurement of neutralisation equivalent and biodegradation studies. The graft copolymer was used for Pb (II) ion removal from aqueous solution. The Pb (II) ion removal capacity of the graft copolymer was also compared with another laboratory developed graft copolymer Amylopectin-g-poly (acrylamide) (AP-g-PAM). Both the graft copolymers were also used for the competitive metal ions removal with Pb (II)/Cd (II), Pb (II)/Zn (II), Pb (II)/Ni (II), Pb (II)/Cu (II) pairs separately under similar conditions. AP-g-poly (AM-co-AA) showed better Pb (II) ion adsorbing power over AP-g-PAM and also much selective towards Pb (II) ions. The adsorption follows a second order rate equation and Langmuir isotherm model.


De S.K.,Midnapore College Autonomous | Beg I.,Lahore School of Economics
Journal of Intelligent and Fuzzy Systems | Year: 2016

This article deals with a new novel defuzzification method for the dense fuzzy sets. In our study, we first define the dense fuzzy set for triangular fuzzy numbers. Then new defuzzification methods have been formulated with crisp convergence tests. Cauchy sequence has been utilized for better illustrations. We show the usefulness and the global justification of newly introduced methods. Applications of new methods in decision making, psychological test, military selection, cryptography, photography, crime research, filtering of noisy environment and risk analysis have been given as its key indexes. © 2016 - IOS Press and the authors.


Kolya H.,Midnapore College Autonomous | Roy A.,Midnapore College Autonomous | Tripathy T.,Midnapore College Autonomous
International Journal of Biological Macromolecules | Year: 2015

Synthesis of Starch-g-(Poly N, N-dimethylacrylamide-co-acrylic acid) was carried out by solution polymerization technique using potassium perdisulfate (K2S2O8) as the initiator. The graft copolymer was characterized by measuring molecular weight, using size exclusion chromatography (SEC), FTIR spectroscopy and X-ray diffraction (XRD) studies. The synthetic graft copolymer was used for removal of hexavalent chromium ion [Cr (VI)] from its aqueous solution. Various operating variables affecting the metal sorption such as, the amount of adsorbent, solution pH, contact time, temperature and the Cr (VI) solution concentration were extensively investigated. FTIR and UV-VIS spectroscopy, cyclic voltammetry (CV) were employed to study the metal complexation. The adsorption data could be well described by the pseudo-second-order and Langmuir isotherm model which indicate a chemisorption process. Calculation of the various thermodynamic parameters for the adsorption was also done. The negative value of free energy change (δG°) indicates the spontaneous nature of the adsorption. © 2014 Elsevier B.V.


Kolya H.,Midnapore College Autonomous | Sasmal D.,Midnapore College Autonomous | Tripathy T.,Midnapore College Autonomous
Journal of Polymers and the Environment | Year: 2016

Grafting of acrylamide (AM), N,N-dimethylacrylamide (DMA) and a mixture of N,N-dimethylacrylamide and acrylic acid (AA) onto starch family namely Starch (St), amylopectin (AP) and hydroxyethyl starch (HES) were carried out by free radical polymerization technique in water medium. The so prepared graft copolymers were characterized by different characterization techniques. The flocculation characteristics of all the graft copolymers were performed in an industrial textile dye effluent, a paper mill waste water and municipal sewage waste water. Their flocculation performances were also evaluated in 0.25 wt% iron ore slime, 1.0 wt% kaolin clay, 1.0 wt% coal and 1.0 wt% silica suspensions separately. A comparative study was also made among the three graft copolymers in each series (St, AP and HES) in all the suspensions along with the real waste water. The flocculation characteristics of the best performing graft copolymer was also compared with some commercial flocculants like magnafloc 1011, telfloc 2230 and percol 181 in all the synthetic suspensions, industrial effluents and municipal sewage waste water. In coal, iron ore slime and silica suspensions and in municipal sewage waste water polysaccharide-g-PDMA showed best results but in kaolin clay suspension, in paper mill effluent and in textile dye effluent polysaccharide-g-(PDMA-co-AA) showed best performance. Among all the graft copolymers, graft copolymer based on HES showed best flocculation performance when compared to other graft copolymers as well as to some commercially available flocculants. © 2016 Springer Science+Business Media New York


Sasmal D.,Midnapore College Autonomous | Singh R.P.,Indian Institute of Science | Tripathy T.,Midnapore College Autonomous
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2015

Amylopectin-g-poly(acrylamide-co-N-methylacrlymide) [AP-g-poly(AM-co-NMA)] was prepared in presence of potassium persulfate (K2S2O8) as the initiator by solution polymerization technique. The synthesised graft copolymer was characterized by various characterization techniques like FTIR, 1H NMR and 13C NMR spectroscopy, thermal analysis and SEM. Biodegradation of the graft copolymers was carried out by enzyme hydrolysis. Flocculation performance of the graft copolymer was evaluated in 1.0wt% coal, 1.0wt% silica, 1.0wt% kaolin, 0.25wt% iron ore and 1.0wt% bentonite clay suspensions. The flocculation efficiency of the graft copolymer was also evaluated by the colour removal capacity from aqueous solution of a synthetic dye, malachite green. A comparative study of the flocculation performance AP-g-poly(AM-co-NMA) was also made with another laboratory synthesised graft copolymer namely amylopectin-g-polyacrylamide (AP-g-PAM) and some commercially available flocculants in the same suspensions and also in the malachite green solution. The results showed that the graft copolymer AP-g-poly(AM-co-NMA) showed better flocculation performance than that of AP-g-PAM as well as to some of the commercial flocculating agents. © 2015 Elsevier B.V.


Kolya H.,Midnapore College Autonomous | Tripathy T.,Midnapore College Autonomous
Polymer International | Year: 2015

Synthesis of amylopectin-graft-poly[(N,N-dimethylacrylamide)-co-(acrylic acid)] was carried out using solution polymerization technique with potassium persulfate as the initiator. The graft copolymer was characterized by measuring molecular weight using size exclusion chromatography, thermal analysis and Fourier transform infrared (FTIR) spectroscopy. The synthetic graft copolymer was used for the removal of some potentially toxic metal ions, Cu(II), Zn(II) and Ni(II), from their aqueous solutions. Various operating parameters like the amount of adsorbent, solution pH, contact time and temperature were studied. The adsorption data were well described by the pseudo-second-order and Langmuir isotherm models. Metal complexation studies were carried out experimentally using cyclic voltammetry and UV-visible and FTIR spectroscopies. The metal complex structure was also studied theoretically using density functional theory with the Gaussian 09 program and the geometry of the complex structure was optimized. The metal complexation ability of the graft polymer was in the order Cu(II) > Ni(II) > Zn(II). Calculation of the various thermodynamic parameters was also done. The negative value of free energy change indicates the spontaneous nature of the adsorption. © 2015 Society of Chemical Industry.


Sasmal D.,Midnapore College Autonomous | Kolya H.,Midnapore College Autonomous | Tripathy T.,Midnapore College Autonomous
International Journal of Biological Macromolecules | Year: 2016

Synthesis, characterization and Cd(II) adsorption studies of a novel biodegradable graft copolymer based on partially hydrolysed polymethylacrylate (PMA) grafted amylopectin was reported, which was prepared by first grafting of PMA chains onto the amylopectin backbone followed by partial alkaline hydrolysis. The hydrolysed graft copolymer (PHAP) was characterized by measuring saponification equivalent (SE), FTIR, 1H NMR and 13C NMR spectroscopy and thermal analysis (TG/DTG). The graft copolymer was biodegradable. Various operating variables affecting the metal sorption such as, amount of adsorbent, solution pH, contact time, temperature and Cd(II) solution concentration were studied which showed that the maximum adsorption of Cd(II) was found at pH 5.5, temperature 90 °C, time 120 min, polymer dose, 0.02 g/L and initial Cd(II) concentration, 50 mg/L. The adsorption data were well described by the pseudo-second-order and Langmuir isotherm model. Metal complexation studies were carried out experimentally using UV–visible, FTIR spectroscopy and theoretically using Density Functional Theory by Gaussian 09 and Gauss view 5.0 programmes which confirms a square planer geometry involving Cd(II) and [Formula presented]− groups. Calculation of the various thermodynamic parameters was also done. The negative value of free energy change indicates the spontaneous nature of the adsorption. © 2016 Elsevier B.V.

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