NOPR Collection:

Synthesis and Surface Studies of CdS / PVK Nanocomposites

Fri, 01 Mar 2019 00:00:00 GMT

Title: Synthesis and Surface Studies of CdS / PVK Nanocomposites Authors: Nagwanshi, Durgesh Nandini; Nigam, Ruchi Abstract: Cadmium sulfide (CdS) is excellent materials for optoelectronic applications. It is interesting to investigate their optical properties at nanometer regime where the properties become size dependent. The nanocomposites have been successfully prepared by chemical method. The samples have been characterized by AFM, SEM and XRD. The XRD study shows formation of CdS nanocrystals with cubic zinc blend crystal structure, having three peaks corresponding to (111), (220) and (311) planes. The crystal size computed by Debye Scherrer’s formula is in the range of 3 to 12 nm. The AFM and SEM studies show the clusters of particles in the range of a few tens of nm. The results obtained from XRD, SEM and AFM studies show increase in particle size, by increasing the CdS concentration in PVK. Page(s): 7-10

Structural, Optical, Photoluminescence and Electroluminescence Properties of Small ZnO Nanocrystals for Optoelectronic Device Applications

Fri, 01 Mar 2019 00:00:00 GMT

Title: Structural, Optical, Photoluminescence and Electroluminescence Properties of Small ZnO Nanocrystals for Optoelectronic Device Applications Authors: Singh, Anju; Vishwakarma, H L Abstract: In this study, zinc oxide (ZnO) has been prepared by chemical precipitation method using zinc acetate as precursor, poly vinyl pyrrolidone (PVP) as capping agent and deionised water as a solvent. X- ray diffraction (XRD), scanning electron microscopy (SEM), ultra violet visible (UV-Vis) absorption, photoluminescence (PL), and electroluminescence (EL) have been performed to characterize the structural, morphological and optical nature of the samples, respectively. X-Ray diffraction indicates that all of the as obtained samples have a pure phase (hexagonal wurtzite structure). Crystallite size has been calculated by Debye Scherrer formula and Lattice strain has been calculated by Williomson Hall equation. Cell volume, Lorentz factor, Lorentz polarization factor, lattice constants and crystal lattice distortion degree (R) and morphology index (MI) have also been studied. The average particle size has also been calculated by Brus equation by using UV-Visible absorption peak. An electroluminescence spectrum of ZnO nanocrystals has also been studied. Page(s): 11-20

Development of Nano SiO2 Particles Dispersed Shape Memory Epoxy Composites

Fri, 01 Mar 2019 00:00:00 GMT

Title: Development of Nano SiO2 Particles Dispersed Shape Memory Epoxy Composites Authors: Patel, Krishan Kumar; Purohit, Rajesh; Hashmi, S A R; Gupta, Ritesh Kumar; Dwivedi, Sandeep Kumar Abstract: Thermo responsive shape memory epoxy based composites are being investigated for their excellent mechanical and thermal properties. In present study the thermosetting epoxy containing different composition of SiO₂ nano particles ranging from 1 to 4 wt. % have been prepared through solvent casting route. Developed composites have been studied for grain analysis, FTIR, shape recovery, impact strength and hardness. Addition of 3 wt. % SiO₂ improves hardness and impact strength significantly. Average grain size of SiO₂particles increase at higher wt. % of SiO₂ in polymer matrix due to agglomeration of nanoparticles. Page(s): 21-24

Effect of Types of Fluids on Fluid Flow Characteristics in Bifurcated Vessel using CFD Simulation

Fri, 01 Mar 2019 00:00:00 GMT

Title: Effect of Types of Fluids on Fluid Flow Characteristics in Bifurcated Vessel using CFD Simulation Authors: Dewang, Yogesh; Panthi, S K Abstract: The present study focuses on the CFD analysis of bifurcated blood vessel using ABAQUS /CFD 6.14 software in order to investigate the effect of types of fluids on resultant velocity and axial velocities of flow. It has been found that out of resultant velocity and axial velocity in three mutually perpendicular directions, types of fluids have significant influence on velocity in z-direction. A significant increment of nearly 45 % in maximum velocity in z-direction has been obtained from benzene to Newtonian blood. Page(s): 25-28