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

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

An effective Nuclear Model: from Nuclear Matter to Finite Nuclei

The momentum and density dependence of mean fields in symmetric and asymmetric nuclear matter are analysed using the simple density dependent finite range effective interaction containing a single Gaussian term alongwith the zero-range terms. Within the formalism developed, it is possible to reproduce the various diverging predictions on the momentum and density dependence of isovector part of the mean field in asymmetric matter. The finite nucleus calculation is formulated for the simple Gaussian interaction in the framework of quasilocal density functional theory. The prediction of energies and charge radii of the interaction for the spherical nuclei compares well with the results of other effective theories.Comment: 10 pages, 3 figures, 2 tables, To appear in the Proceedings of the 11th International Conference on Nucleus-Nucleus Collisions (NN2012), May 27-June 1, 2012, San Antonio, Texas, US

Wear studies of Al-Si alloys

There are many properties of Aluminium-Silicon alloys such as high wear resistance, light weight, low coefficient of thermal expansion and high strength to weight ratio, that makes it suitable for many industries. In recent years, it has gained huge acceptance in automotive industries, as its use results in fuel saving, hence cost saving. These advancements make the study of properties of Al-Si alloys important. In the present study, wear behavior of Al-Si alloys were studied. Aluminium containing 10 weight % of Silicon was synthesized using casting method. The microstructure showed the presence of Proeutectic silicon. Wear behaviour was studied by using computerized pin on disc wear testing machine. The abrasion of the alloy increased as sliding distance and time increased. The crack morphology of the worn surfaces were analysed using stereo microscope

Development and Ergonomic Evaluation of Manually Operated Weeder for Dry Land Crops

A manually operated weeder for dry land crops was developed and evaluated to find its performance. It was compared with other available weeders namely wheel finger weeder, wheel hoe and conventional weeding by using trench hoe for groundnut crop at four levels of soil moisture content of 13.52, 11.63, 9.52 and 8.04 per cent (db). It was found that the heart rate, oxygen consumption rate and energy consumption rate increases with decrease in soil moisture content for all the treatments. The highest performance index of 3689.74 was obtained with developed weeder at 11.63 per cent moisture content. Lowest plant damage (2.46 to 7.96%) and lower energy consumption rate (8.34 to 40.05 kJ/min) with highest performance index (678.66 to 3689.74) of developed weeder at different soil moisture content proved its superiority over other weeders. Soil moisture of 11.63 per cent was found to be optimum for weeding in groundnut crop and the cost of operation of developed weeder at this soil moisture content was found to be Rupees 244.00 as against Rupees 2450.00 per hectare in conventional method of weeding by using trench hoe