10,245 research outputs found

    Investigation of Complex Impedance and Modulus Properties of Nd Doped 0.5BiFeO3-0.5PbTiO3 Multiferroic Composites

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    0.5BiNdxFe1-xO3-0.5PbTiO3 (x=0.05, 0.10, 0.15, 0.20) composites were successfully synthesized by a solid state reaction technique. At room temperature X-ray diffraction shows tetragonal structure for all concentrations of Nd doped 0.5BiFeO3-0.5PbTiO3 composites. The nature of Nyquist plot confirms the presence of bulk effects only for all compositions of Nd-doped 0.5BiFeO3-0.5PbTiO3 composites. The bulk resistance is found to decreases with the increasing in temperature as well as Nd concentration and exhibits a typical negative temperature coefficient of resistance (NTCR) behavior. Both the complex impedance and modulus studies have suggested the presence of non-Debye type of relaxation in the materials. Conductivity spectra reveal the presence of hopping mechanism in the electrical transport process of the materials. The activation energy of the composite increases with increasing Nd concentration and were found to be 0.28, 0.27, 0.31 and 0.32eV for x=0.05, 0.10, 0.15, 0.20 respectively at 200-275 oC for conduction process.Comment: 22 pages, 12 figures, 2 tables, 34 Referenc

    Designing terry fabric for improved serviceability

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    Various terry fabrics (cotton) having different constructional parameters have been designed and the effect of washingtreatment on water absorbency, surface characteristics and compression characteristics are studied. To establish the optimumloop length and loop density of terry fabrics at which they can withstand maximum number of washing cycles withoutaffecting water absorbency, surface characteristics and compression characteristics, terry fabrics having the same yarn andfabric parameters are washed under industrial conditions for 10 washing cycles. After each cycle, the rate of waterabsorption, total amount of water absorbed, surface characteristics and compression characteristics are evaluated bygravimetric absorbency testing system, image analysis techniques and KES-FB-3 testing system respectively. Another groupof cotton terry fabrics having different loop length and loop density have been studied to optimise these two important fabricparameters to increase the life of fabric. It is observed that the rate of water absorption, the total amount of water absorbedand the surface characteristics improve with increase in washing cycle, but after 8th washing cycle these parameters startdeteriorating. Maximum possible loop density and loop length of 15 - 17 mm give maximum life of terry fabric i.e. thefabric can perform well even after 10 washing cycles. This study will certainly help in increasing the life of terry fabric,developing high quality towel fabric by providing information on absorbency, surface characteristics and compressioncharacteristics of fabric before and after washing along with the values of loop length and loop density