Pandit Deendayal Petroleum University

About: Pandit Deendayal Petroleum University is a education organization based out in Gandhinagar, Gujarat, India. It is known for research contribution in the topics: Welding & Computer science. The organization has 996 authors who have published 1804 publications receiving 16594 citations.

Elucidation of size, structure, surface plasmon resonance, and photoluminescence of Ag nanoparticles synthesized by pulsed laser ablation in distilled water and its viability as SERS substrate

Abstract: In the present work, silver nanoparticles have been synthesized as a function of laser irradiation time and incident laser fluence by focusing a second harmonic of a Q-switched Nd:YAG laser. Increase in the irradiation time from 5 to 30 min at fixed incident laser fluence of ~ 10 J/cm2 per pulse resulted in a decrease in the average size of the nanoparticles from 20 to 15 nm, respectively. The average size of the nanoparticle was further reduced to 10 nm by increasing the incident laser fluence to ~ 22 J/cm2 at fixed irradiation time of 30 min. The reduction in the size of the nanoparticles from 20 to 15 nm induced a blue shift in the plasmonic peak from 403 to 398 nm, but with further decrease in size, a reversing of the peak towards longer wavelength was observed. The structural features of the nanoparticles exhibited dependence on both the process parameters as revealed by the X-ray diffraction, selected area electron diffraction, and high-resolution transmission electron microscope images. Longer irradiation time and higher incident fluence resulted in more oxidized phases of silver nanoparticles. These nanoparticles were found to be photoluminescent, having broad emission around the plasmonic excitation wavelength. A study on the effect of the particle size and concentration of the synthesized silver nanoparticles on its viability as surface-enhanced Raman scattering substrate for a bioactive furanoflavonoid, karanjin is reported.

A dual-band high-gain microstrip antenna with a defective frequency selective surface for wireless applications

Abstract: A dual-band high-gain linearly polarized antenna for wideband operation using a defective frequency selective surface (DFSS) is proposed and demonstrated experimentally. The designed antenna consis...

Heating of liquid foods in cans: Effects of can geometry, orientation, and food rheology

Abstract: In this work, the effect of geometry and orientation of food cans on the heating characteristics of processed liquid foods and the resulting lethality target values as a function of the processing times have been investigated. For this purpose, the governing differential equations have been solved numerically for elliptical and cylindrical cans of varying aspect ratios in different orientations in order to delineate their effect on the heating rate (especially of the slowest heating zone [SHZ]) and lethality values over wide ranges of rheological features including shear thinning (n 1) behaviors. The flow and heat transfer characteristics were analyzed with the help of velocity vectors, isotherm contours, average Nusselt number, SHZ temperature and heat penetration parameters, and lethality target values. Also, comparisons were made in terms of the sterilization time and heat penetration parameters to identify the preferable geometries and orientations of food cans for effective heating of non-Newtonian foodstuffs. Finally, favorable conditions in terms of the shape and orientation of the can and the rheological properties have been delineated which lead to superior heating characteristics.

Electrochemical Properties of Highly Sensitive and Selective CuO Nanostructures Based Neurotransmitter Dopamine Sensor

Abstract: In this article, electrochemical properties of CuO nanostructures based dopamine (DA) sensor was investigated. The morphology, structure, optical, and compositional properties of the CuO nanostructures were characterized by using SEM, XRD, UV-Vis, and XPS techniques. The electrochemical properties were investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques. The CV results indicate that biosensors based on CuO nanostructures exhibit a high selectivity and sensitivity of 0.1975 μA μM–1 toward DA and effectively avoids the interference of ascorbic acid (AA) and uric acid (UA). The obtained EIS spectra for CuO sensors were analysed using an electrical equivalent circuit to understand the bulk and surface response via the capacitive and resistive parameters. The EIS measurement also leads to the direct determination of parameters like series resistance and ion diffusion phenomena at electrode-electrolyte interface. The experimental CV and EIS results along with their analysis will have a significant impact on understanding the mechanism of high sensitivity and selectivity performance of CuO based sensors. This study may also lay the basis for efficient characterization of biosensors by coupling both the CV and EIS characterization techniques.