Subhash Nimanpure; S. A. R. Hashmi; Rajnish Kumar; Archana Nigrawal; H.N. Bhargaw; Ajay Naik
Abstract
Environment friendly electrical insulation material was developed using bio based rectangular cross sectioned sisal fibrils as reinforcement. High content cellulose base fibrils fibrillated by mechanical disintegration method into macro and micro fibrils from coarse sisal fibre. This fibrils were randomly ...
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Environment friendly electrical insulation material was developed using bio based rectangular cross sectioned sisal fibrils as reinforcement. High content cellulose base fibrils fibrillated by mechanical disintegration method into macro and micro fibrils from coarse sisal fibre. This fibrils were randomly distributed in polymer matrix. These composites were characterized in term of electrical, mechanical and thermal properties to investigate the stability for high strength electrical insulation materials. Excellent mechanical properties were observed. Tensile, flexural and impact strength of composites at 40 wt. % fibril loading improved by 151.34, 197.43 and 360.07 % as compared to unsaturated polyester resin. A few micro-mechanical models were compared with the experimental values. Nielson-Chen Model predicted the experimental data most accurately. The electrical properties of surface modified sisal fibril composites improved significantly in higher frequency. DSC analysis showed that the decomposition temperature of composite was higher, around 22°C than that of the polyester resin. Thermal degradation reduced and was observed in the range of 83-87% of fibril composites as compared to 97% of resin. Fibril composites are highly sensitive to electrical frequency and exhibit excellent electrical insulation property at 20 kHz. Alkali treated fibril based composites resulted an environment friendly thermally stable, high strength insulation material. Copyright © 2018 VBRI Press.
Anil S. Meshram; Ompraksh P. Chimankar; Yashwantrao D. Tembhurkar
Abstract
Thin films of CuInTe2(1-x)S2x were grown by spray pyrolysis and develop thin films on glass substrate at 350C by varying proportion x in the range of 0.25. Aqueous solutions of cupric chloride, indium tri-chloride, thio-urea and tellurium tetra-chloride mixed in proper composition x and studies their ...
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Thin films of CuInTe2(1-x)S2x were grown by spray pyrolysis and develop thin films on glass substrate at 350C by varying proportion x in the range of 0.25. Aqueous solutions of cupric chloride, indium tri-chloride, thio-urea and tellurium tetra-chloride mixed in proper composition x and studies their electrical properties of all these films. The resistivity of the films was measured for temperature ranging from 77 K to 473 K. The activation energies values were calculated from Arrhenius plot. At very low temperature a variable range hopping conduction mechanism appears to be operative. Surface of thin films has been studied by Scanning Electron Microscope. Copyright © 2018 VBRI Press.
P. Prabukanthan; R. Lakshmi; T. Rajesh Kumar; S. Thamaraiselvi; G. Harichandran
Abstract
Electrochemical deposition (ECD) of FeS2 thin films from aqueous solution contains FeSO4, Na2S2O3.5H2O and H2SO4. ECDs were performed at different bath temperatures (30, 40, 50, 60 and 70°C) with constant pH (~2). FESEM images shows that the grains are as deposited films with stoichiometric ...
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Electrochemical deposition (ECD) of FeS2 thin films from aqueous solution contains FeSO4, Na2S2O3.5H2O and H2SO4. ECDs were performed at different bath temperatures (30, 40, 50, 60 and 70°C) with constant pH (~2). FESEM images shows that the grains are as deposited films with stoichiometric iron pyrite thin films were successfully formed at 50, 60 and 70°C and S/Fe ratio in as-deposited films were ~2. GAXRD studies of as-deposited at 30 and 40°C FeS2 thin films shows a minor phase of orthorhombic marcasite and major cubic pyrite phase observed. As-deposited thin films at 50, 60 and 70°C brings about the formation of FeS2 with single crystalline cubic phases with a strong (111) preferred orientation and without any contribution of marcasite phase. When the bath temperature was increased, as-deposited thin films of crystalline size, thickness and roughness value increased due to rate of formation FeS2 increased. Raman spectra of the FeS2 thin films presented characteristic peaks of S-S active mode at 377 cm-1. The optical spectra of the as-deposited FeS2 thin films with different bath temperatures showed a clear absorption edge band gap of these films from 0.86 to 0.96 eV. As-deposited FeS2 thin films at different bath temperatures show p-type conductivity. Copyright © 2017 VBRI Press.
Anandraj J; Girish M. Joshi; Mayank Pandey
Abstract
We have demonstrated the successful preparation of polyvinyl alcohol (PVA) composed CuBi2S3 polyionic (PI) composites. Polymer composites were sensitive to the external stimuli, the modified PVA moiety exhibits excellent electrical property as a function of temperature. The volume resistance measured ...
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We have demonstrated the successful preparation of polyvinyl alcohol (PVA) composed CuBi2S3 polyionic (PI) composites. Polymer composites were sensitive to the external stimuli, the modified PVA moiety exhibits excellent electrical property as a function of temperature. The volume resistance measured by impedance analyzer (40 to 150oC) under broadband frequency (50Hz -1MHz). The negative temperature coefficient (NTC) was observed in the temperature range of 40 to 150oC. It offers the nonlinear resistivity, ρ = 105 (Ω-m) across pure PVA moiety. The influence of polycationic-ions crucial to obtain the gradual decrease of resistivity (ρ) up to 104 (Ω-m). The thermistor characteristics were disclosed as function of polyionic loading (wt %). Copyright © 2017 VBRI Press
