Browsing by Author "Mishra, V."

Now showing 1 - 4 of 4

Development and Characterization of Epoxy-Based Polymeric Composite with Bio-particulates as Filler Material
(Springer Science and Business Media Deutschland GmbH, 2022) Chandraker, S.; Dutt, J.K.; Agrawal, A.; Roy, H.; Rajkumar; Chandrakar, K.; Mishra, V.
The focus of this paper is to develop cheap and unconventional materials for both structural and non-structural applications using eco-friendly bio-wastes. The study used pistachio nutshells (normally disposed of as waste) for fabricating bio-particulate-based polymeric composites. In this investigation, epoxy is taken as matrix material and pistachio nutshells in the form of microparticles are used as filler material. Six different sets of composites with varying filler content up to a maximum of 30 wt% are fabricated by a hand lay-up method. The excellent compatibility and bonding between the matrix and filler material under investigation are confirmed by micrograph obtained from scanning electron microscopy and by Fourier-transform infrared spectroscopy analysis. Physical and mechanical properties are evaluated experimentally as per ASTM. Apart from that, a linear viscoelastic semi-solid model is reported here to understand the mechanical dynamic behaviour of the developed material. On the basis of several test result, the developed composite may find its potential application in light-duty structures efficiently. © 2021, King Fahd University of Petroleum & Minerals.
Electric fields in the transition region of sphere-gaps to parallel-plane gaps
(2004) Punekar, G.S.; Mishra, V.; Kishore, N.K.; Shastry, H.S.Y.
The electrode gaps which results in to uniform electric fields are the most widely used gap configurations in assessing dielectric strength. In the present study simulation results of parallel plane electrode gap configurations with symmetrical and unsymmetrical supply are reported. When plane radius of plane electrode is reduced the plane electrode at Its extreme case forms a sphere resulting in to sphere gap arrangement Results in this transition region are reported. The Charge Simulation Method (CSM) is used to compute electric fields; with errors in simulation being less than 0.06% (in potential). Simulation results indicate that as the plane radius increases the field uniformity increases. Non uniformity for a given plane radius depends on the gap spacing. For given gap spacing when the plane radius of the electrode is more than the gap spacing, improvement In uniformity are not significant The unsymmetrical supply results in higher field non-uniformity in the gap. The height of high voltage (H.V.) electrode above the ground plane (designated as parameter "A" in IS 1876-1961 for sphere gaps with vertical electrode arrangement) has shown negligible influence on the electric field distribution in the gap. � 2004 IEEE.
Electric fields in the transition region of sphere-gaps to parallel-plane gaps
(2004) Punekar, G.S.; Mishra, V.; Kishore, N.K.; Shastry, H.S.Y.
The electrode gaps which results in to uniform electric fields are the most widely used gap configurations in assessing dielectric strength. In the present study simulation results of parallel plane electrode gap configurations with symmetrical and unsymmetrical supply are reported. When plane radius of plane electrode is reduced the plane electrode at Its extreme case forms a sphere resulting in to sphere gap arrangement Results in this transition region are reported. The Charge Simulation Method (CSM) is used to compute electric fields; with errors in simulation being less than 0.06% (in potential). Simulation results indicate that as the plane radius increases the field uniformity increases. Non uniformity for a given plane radius depends on the gap spacing. For given gap spacing when the plane radius of the electrode is more than the gap spacing, improvement In uniformity are not significant The unsymmetrical supply results in higher field non-uniformity in the gap. The height of high voltage (H.V.) electrode above the ground plane (designated as parameter "A" in IS 1876-1961 for sphere gaps with vertical electrode arrangement) has shown negligible influence on the electric field distribution in the gap. Â© 2004 IEEE.
Mechanical and Thermal Properties of Sisal Fiber-Based Composites
(wiley, 2021) Mishra, V.; Agrawal, A.; Chandraker, S.; Sharma, A.
Natural fibers have attracted the scientific community toward their usage as reinforcement in polymeric composites mainly because of multiple benefits such as low cost, huge/easy availability, easy processing, and growing concern toward environmental awareness as they are biodegradable. Reinforcing natural fibers is an efficient approach toward reducing the consumption of nonbiodegradable plastic material. Also, natural fibers are promising reinforcing materials that can replace different synthetic fibers. Among the various natural fibers available, sisal fiber as reinforcement in a polymeric matrix is a strong competitor. Sisal fiber has several advantages like they are the widely used natural fiber and has the second-largest consumption across the world after cotton. It has high strength with good durability. It also has a good percentage of elongation before the break and does not deteriorate quickly in salty water. These fibers are smooth and straight with a high degree of inflexibility. Sisal represents around 2% of the total cultivation among plant fibers. In this regard, the present chapter focuses on sisal fiber as reinforcement with different polymeric matrices. The main emphasis is on the mechanical and thermal behavior of composite understudy and applications of this category of composites in various fields. A review of selected work on the research of sisal fiber with polymer matrix is the content of this chapter. © 2022 WILEY-VCH GmbH, Boschstr. 12, 69469 Weinheim, Germany.