Singaravelu Vivekanandhan

Bio: Singaravelu Vivekanandhan is an academic researcher from University of Guelph. The author has contributed to research in topics: Nanocrystalline material & Silver nanoparticle. The author has an hindex of 22, co-authored 67 publications receiving 2656 citations. Previous affiliations of Singaravelu Vivekanandhan include Pondicherry University.

Composites from renewable and sustainable resources: Challenges and innovations.

Abstract: Interest in constructing composite materials from biosourced, recycled materials; waste resources; and their combinations is growing. Biocomposites have attracted the attention of automakers for the design of lightweight parts. Hybrid biocomposites made of petrochemical-based and bioresourced materials have led to technological advances in manufacturing. Greener biocomposites from plant-derived fiber and crop-derived plastics with higher biobased content are continuously being developed. Biodegradable composites have shown potential for major uses in sustainable packaging. Recycled plastic materials originally destined for landfills can be redirected and repurposed for blending in composite applications, thus leading to reduced dependence on virgin petro-based materials. Studies on compatibility of recycled and waste materials with other components in composite structure for improved interface and better mechanical performance pose major scientific challenges. This research holds the promise of advancing a key global sustainability goal.

Nanofibers: effective generation by electrospinning and their applications.

Abstract: Electrospinning is the most versatile technology in use today, for the generation of polymer nanoscale fibers. The nano materials generated using this technology have a large surface area and are highly porous making it very useful in many applications in diverse fields such as energy storage, healthcare, biotechnology, environmental engineering, defense and security. The production of the fibers and the morphology can be easily controlled by modifications to the processing parameters. The relatively high production rate and simplicity of the setup makes electrospinning highly attractive. This review summarizes the effect of various processing parameters on the effective generation of nanofibers. By simple modifications to the electric field inside the electrospinning chamber the fiber collection can be easily controlled. In addition, the various applications of electrospun fibers in electronic devices, environmental sensors and filters, energy storage, and in biomedicine such as in tissue engineering, drug delivery and enzyme encapsulation are examined and the current research in each field is also explored in this review.

Biosynthesis of silver nanoparticles using murraya koenigii (curry leaf): An investigation on the effect of broth concentration in reduction mechanism and particle size

Abstract: Biological synthesis of silver nanoparticles using Murraya koenigii leaf extract was investigated and the effect of broth concentration in reduction mechanism and particle size is reported. The rapid reduction of silver (Ag + ) ions was monitored using UV-visible spectrophotometry and showed formation of silver nanoparticles within 15 minutes. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) analysis showed that the synthesized silver nanoparticle are varied from 10-25 nm and have the spherical shape. Further the XRD analysis confirms the nanocrystalline phase of silver with FCC crystal structure. From this study, it was found that the increasing broth concentration increases the rate of reduction and decreases the particle size. Copyright © 2011 VBRI press.

Soybean (Glycine max) Leaf Extract Based Green Synthesis of Palladium Nanoparticles

Abstract: Palladium (Pd) nanoparticles were synthesized using protein rich soybean leaf extract based biological process. Reduction of palladium ions by soybean leaf extract was examined by UV-visible spectroscopic technique. It was believed that the proteins and some of the amino acids that are exist in soybean leaf extracts were actively involved in the reduction of palladium ions. Further it was confirmed by Fourier transformations infrared spectroscopic (FTIR) analysis. These amino acids are not only involving in the reduction of palladium ions but also acting as surfactants that inhibits the rapid agglomeration. The phase purity of the synthesized palladium nanoparticles was investigated through X-Ray Diffraction (XRD) analysis and the obtained pattern was compared with JCPDS data. Transmission electron microscopic (TEM) images of the palladium particles were recorded and the particle size was found to be ~15 nm.

Ultracapacitors: Why, How, and Where is the Technology

Abstract: The science and technology of ultracapacitors are reviewed for a number of electrode materials, including carbon, mixed metal oxides, and conducting polymers. More work has been done using microporous carbons than with the other materials and most of the commercially available devices use carbon electrodes and an organic electrolytes. The energy density of these devices is 3¯5 Wh/kg with a power density of 300¯500 W/kg for high efficiency (90¯95%) charge/discharges. Projections of future developments using carbon indicate that energy densities of 10 Wh/kg or higher are likely with power densities of 1¯2 kW/kg. A key problem in the fabrication of these advanced devices is the bonding of the thin electrodes to a current collector such the contact resistance is less than 0.1 cm2. Special attention is given in the paper to comparing the power density characteristics of ultracapacitors and batteries. The comparisons should be made at the same charge/discharge efficiency.

Combustion synthesis and nanomaterials

Abstract: The recent developments and trends in combustion science towards the synthesis of nanomaterials are discussed. Different modifications made to conventional combustion approaches for preparation of nanomaterials are critically analyzed. Special attention is paid to various applications of combustion synthesized nanosized products.

Green Synthesis of Metallic Nanoparticles via Biological Entities

Abstract: Nanotechnology is the creation, manipulation and use of materials at the nanometre size scale (1 to 100 nm). At this size scale there are significant differences in many material properties that are normally not seen in the same materials at larger scales. Although nanoscale materials can be produced using a variety of traditional physical and chemical processes, it is now possible to biologically synthesize materials via environment-friendly green chemistry based techniques. In recent years, the convergence between nanotechnology and biology has created the new field of nanobiotechnology that incorporates the use of biological entities such as actinomycetes algae, bacteria, fungi, viruses, yeasts, and plants in a number of biochemical and biophysical processes. The biological synthesis via nanobiotechnology processes have a significant potential to boost nanoparticles production without the use of harsh, toxic, and expensive chemicals commonly used in conventional physical and chemical processes. The aim of this review is to provide an overview of recent trends in synthesizing nanoparticles via biological entities and their potential applications.