Jashanpreet Singh, Rana Gill, Satish Kumar, S.k. Mohapatra,
Volume 19, Issue 4 (Desember 2022)
Abstract
In this paper, an investigation was carried out to test the suitability of potential additive materials in
WOKA 3533 (WC-10Co4Cr) cermet HVOF coating subjected to slurry erosion in ash conditions. The additives
namely molybdenum carbide, yttrium oxide, and zirconium oxide were added in equal percentages (3 wt.%) in
WOKA cermet powder. High-velocity oxy-fuel (HVOF) spraying was performed to develop the additive-based
WOKA cermet coatings. The slurry erosion in ash conditions was tested using the pot tester. Microstructural and
mechanical properties of traditional and additive-based WOKA cermet coatings were also tested in the present
study; for example, microstructure, crystalline phases of as-sprayed coatings, and microhardness. Results present a
comparison of surface erosion wear of different cermet coatings. It was found that the yttrium oxide was a suitable
additive for the WOKA cermet coatings than the molybdenum carbide. However, zirconium oxide is unsuitable for
WOKA cermet coatings in erosion wear applications.
Divya Tripathy, Anita Kushwaha, Smrita Singh, Smriti Dwivedi, Anjali Gupta, Lalit Prasad, Ashutosh Chauhan,
Volume 21, Issue 0 (IN PRESS 2024)
Abstract
Organosilicon compounds represent a fascinating class of molecules with diverse structures, unique bonding characteristics, and wide-ranging applications across various fields. The structural diversity of organosilicon compounds arises from the versatility of silicon, which can form a variety of chemical bonds, including single, double, and triple bonds with carbon, as well as bonds with other heteroatoms such as oxygen, nitrogen, and sulfur. This diversity enables the synthesis of an extensive range of organosilicon molecules, including silanes, siloxanes, silanols, silazanes, and silsesquioxanes, among others. The unique properties of these compounds, such as thermal stability, chemical inertness, and flexibility, make them valuable building blocks for the design of advanced materials.Organosilicon compounds find applications in diverse fields, including materials science, pharmaceuticals, electronics, and agriculture. In materials science, they are used as coatings, adhesives, sealants, and modifiers to impart desirable properties such as water repellency, thermal resistance, and biocompatibility. In the pharmaceutical industry, organosilicon compounds serve as drug delivery agents, imaging agents, and synthetic intermediates due to their biocompatibility and tunable properties. In electronics, they are employed as dielectric materials, insulators, and encapsulants in semiconductor devices. Current review aims to unlock new opportunities for the development of innovative materials and technologies with enhanced performance and functionality.
Richa Singh,
Volume 21, Issue 1 (March - Special Issue 2024)
Abstract
Drug-resistance among bacteria is a concerning issue in medical field. Silver nanoparticles (AgNPs) are one of the promising novel nano-antibiotics. In the present study, AgNPs were synthesized using cell-free extract of Acinetobacter sp. challenged with silver nitrate. Preliminary observations done using UV-Vis spectrophotometry at 420 nm. Complete reduction of silver ions to AgNPs was confirmed through cyclic voltammetry. Electron microscopy revealed formation of spherical shaped nanoparticles of size upto 20 nm. These AgNPs were furthr used to determine their effect on activity of various antibiotics against pathogenic bacteria such as Neisseria and Xanthomonas. Higher antibacterial activity of AgNPs was observed against Gram-negative bacteria. Enhanced antibacterial action of AgNPs was observed with selected beta-lactam antibiotics producing upto 3-fold increase in area of zone of inhibition. On exposure to AgNPs, the minimum inhibitory concentration and minimum bactericidal concentration of antibiotics were lowered by upto 2000 times indicating potential synergistic action of AgNPs. This study clearly signifies that the drug, proved to be inefficient due to bacterial resistance, could be made functional again in presence of AgNPs. This will help in development of novel antibacterial formulations containing antibiotics and nanoparticles to combat multiple drug-resistance in microorganisms.
