IOSR-JAP   Volume-15 ~ Issue-2 ~ Mar. – Apr. 2023

ABSTRACT: Pure and Zn, PVP and Ag doped tin oxide nanoparticles were prepared by microwave assisted chemical co-precipitation method. The influence of zinc, PVP and Ag nanoparticles in tin oxide is obtained by X-ray Diffraction pattern and Electrical conductivity studies. The Ag and Zn ions replaced the tin ions in tin oxide lattice sites. Therefore, no zinc and silver peaks are observed in XRD. There is no impurity peak observed in XRD. The X-ray diffraction pattern reveals the tetragonal rutile structure of tin oxide nanoparticles. Increasing the doping concentration of zinc in tin oxide decrease the crystalline size. The band gap of pure and zinc, PVP and Ag doped tin oxide nanoparticles are calculated from Diffuse reflectance spectroscopy.The conductivity studies of the doped samples is increased due to the Ag nanoparticles.

Keywords: UV-Visible absorption spectroscopy, SnO2 nanoparticles, Conductivity, Bandgap.

[1]. Aparna G, Anubhav S, Santanu C, Titash M, Influence of Nanofillers on Adhesion Properties of Polymeric Composites. Acs omega 2022; 7:3844−3859.
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[3]. Mei G, Li Z, Yi Z, Qin Z, Yanying W, Li W, Yubao L, Investigation on the Interpenetrating Polymer Networks (IPNs) of Polyvinyl Alcohol and Poly (N-vinyl pyrrolidone) Hydrogel and Its In Vitro Bioassessment. Journal of Applied Polymer Science, 2012; 125, 2799–2806.
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ABSTRACT: We present dispersion measure (DM) variations analysis for 68 pulsars with data collected from LOFAR.TheobservationsweretakenusingsixInternationalLOFARStationsinEurope: FR606 in France, SE607 Sweden and DE601, DE602, DE603 stations in Germanyovertheperiod of 3.5 years (between June 2014 and November 2017) at the frequency of 150MHzwith80MHzofbandwidth.Duringthistime the total number of pulsars observed with FR606 and used is 21, SE607-13 pulsars while a set of 34 sources was obtained from four stations in Germany which makes the total of 68 pulsars.......

Keywords: Pulsar, general - ISM Structure, Dispersion measure, LOFAR

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ABSTRACT: An investigation on the role of interplanetary magnetic field on the periodic variation of cosmic rays has been carried out. This was done using cosmic rays data from three neutron stations of SOPO, CLMX & MOSC, and interplanetary magnetic field data from the year 2000 to 2005. It was observed that solar activities gives rise to a sharp depression in the intensity of cosmic ray variation known as Forbush decrease (FD). Manual approach was used to select the FD event dates which detected new FD dates. An epoch analyses was carried out on the selected FD dates using R. program.......

Keywords: Magnetic Field, Periodic Variations, Forbush decrease (FD)

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