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1

Influence of fibre loading and surface treatment on the impact strength of coir polyester composites

Karthikeyan S.

Archives of Materials Science and Engineering

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2021

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Vol. 107, nr 1

16--20

EN

Purpose: In this work, coir fibre with varying fibre content was selected as reinforcements to prepare polymer-based matrices and the problem of reduced fibre-matrix interfacial bond strength has been diluted by chemical treatment of coir fibres with alkali solution. Design/methodology/approach: The effect of fibre loading, solution concentration and soaking time on the impact strength of the composites were analyzed using statistical techniques. Response Surface Methodology (RSM) approach was used to model and optimize the impact properties of coir-polyester composites. Findings: The impact strength of coir fibre reinforced polyester composite depends mainly on the fabrication parameters such as fibre-polyester content, soaking time, concentration of soaking agent and adhesive interaction between the fibre and reinforcement. Research limitations/implications: The mechanical properties of any coir polyester composite depend on the nature bonding between the fibre and reinforcement. The presence of cellulose, lignin on the periphery of any natural fibre reduces the bonding strength of the composite. This limitation is overcome by fibre treatment over sodium hydroxide to have better impact properties. Practical implications: Now days, natural fibre reinforced composites are capable of replacing automotive parts, subjected to static loads such as engine Guard, light doom, name plate, tool box and front panels etc. These materials can withstand any static load due to its higher strength to weight ratios. Originality/value: The effect of fibre loading, solution concentration and soaking time on the impact strength of the composites were analyzed using statistical techniques. Response Surface Methodology (RSM) approach was used to model and optimize the impact properties of coir-polyester composites. The impact strength of NaOH impregnated coir fibre reinforced polyester composites was evaluated.

2

Study on extraction of pollutant free flammable fuel from contaminated automobile waste lube oil

Thanikachalam J., Karthikeyan S.

Journal of Achievements in Materials and Manufacturing Engineering

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2020

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Vol. 100, nr 2

78--84

EN

Purpose: of this paper is to investigate the reusability of contaminated waste lubricant oil as flammable fuel by thermal and catalytic cracking process followed by distillation. It also includes the study of using Zeolite and Nickel nano particles as catalyst and its influence catalytic cracking. Design/methodology/approach: A conventional sterilization technique called Autoclaving method, uses high-pressure steam to separate water and other solid waste from the lube oil. It is followed by thermal cracking which breaks the molecular chains and decompose the waste lube oil. The autoclaving process works by the concept that the boiling point of water (or steam) increases when it is under pressure. Findings: Now a days, Industrial and Automobile waste lubricating oils are giving big threat ecology while burning and disposing on bare land. Furthermore, they discharged into the open environment which might make destructive sicknesses to ecology. In water, oil is a visible pollutant, floating as a scum on the surface. Moreover, there is a gradual rise in fuel requirement across the globe, and the consumption of oil assets have driven the researchers to find elective power for internal combustion engines. By the way, diminishing of fossil sources, growing of demand and cost of petroleum based fuels and its environmental hazards as a result of burning or disposing on land have encouraged to investigate possibility of recycling of waste engine oil. Research limitations/implications: A series of process such as filtration, cracking followed by distillation needs expensive experimental setup and regular maintenance as the extracted flammable oil fuel possess significant range of dynamic viscosity values. As all real fluids has its own viscosity, in near future, an investigation is about to do on its behaviour on blending with other flammable fluids. Practical implications: Although the result of this investigation conforming its flammable characteristic of the extracted fuel, the quantity of pollutant free flammable fuel from waste contaminated lube oil being extracted is significant, the cost of catalyst is considerably more, as it plays the most vital part in cracking. This effort likely also reduces foreign exchange, reduces greenhouse emissions and enhances regional development especially in developing countries. Originality/value: The novelty of the work is to prepare pollutant free flammable fuel from waste Lube oil by catalytic cracking process. Here Zoelite and Nickel nanoparticles are used as catalyst which breaks the long-chain molecules of the high boiling hydrocarbon liquids into much shorter molecules.

3

Preparation and characterization of nano magnetic fluid for automotive applications

Thanikachalam J., Nagaraj P., Karthikeyan S.

Archives of Materials Science and Engineering

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2019

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Vol. 96, nr 2

49--55

EN

Purpose: of this paper is to prepare a nano magnetic fluids with nano additives to have the combined characteristics of high yield stress and better magnetic properties for smart vehicles. This study focuses on increasing the sedimentation time of the fluid using suitable nano additive nickel along with graphene as fillers. Design/methodology/approach: Magnetic nano sized nickel particle based electromagneto-rheological fluid was prepared and graphene nanoparticle with thickness less than 10nm was introduced as an additive to reduce its sedimentation. This added plate like graphene acts as filler which seals the interfaces of nickel particles and thereby it improves the resistance to sedimentation. Triton X 100 was added as the surfactant for the fluid to reduce the agglomeration of the particles. Findings: Morphology of pure nickel and graphene were examined using scanning electron microscopy (SEM) images. Research limitations/implications: The important limitations is that freely dispersed micron sized iron particles could settle over a period of time, in the form of cakes at the bottommost, and it is tedious to recuperate as dispersed phase. In this investigation, nano sized nickel particles were used as additive to reduce the sedimentation of micron sized iron particles so that, the mixture is homogeneous for extended period of time. In future, addition of different types composite additives in the magnetorheological fluid could be made for the better sedimentation control. Practical implications: The sedimentation problem is one of the major drawback in the smart fluids, which can be eliminated by adding nano particles. For conventional fluid, the complete sedimentation will occur in 2 hours while the improved nano magnetic fluid with additive has good resistance to settle the micron sized iron particle up to 10 hours. Originality/value: To prepare a low cost magnetorheological fluid with nano additives like nickel particles along with fillers as graphene nano particles. With this addition of nickel and inclusion of graphene, the sedimentation problem in magnetorheological fluids is significantly reduced. This magnetorheological fluids can be used in brakes and dampers of automobiles.

4

Studies on some Primary Metabolites Extraction and Quantification in Different Plant Parts of Eupatorium triplinerve Vahl.

Sugumar N., Karthikeyan S.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 49

66--73

EN

Medicinal plant is most exclusive sources of life saving drugs for the majority of the world population. Laboratory evaluations were made assess the study of primary metabolites of various plants in selected species Eupatorium triplinerve Vahl. During the present investigation comparative study of primary metabolites Carbohydrates, Protein, Ascorbic acid, Starch, Sugar, Chlorophyll, Carotenoids and Total phenol of genus Eupatorium triplinerve were undertaken for study and all the their chemical composition. The leaf highest amount of chlorophyll-a (4.95gm), chlorophyll-b (4.05gm), carotenoids (3.29gm),ascorbic acid (41.13gm/gdm), sugar (3.92gm/gdm), starch(5.89gm/gdm)protein (67.82µg/mg), total phenol (84.00gm/gdm). The root lowest amount of sugar (2.00gm/gdm), starch (3.15gm/gdm), protein (60.01µg/mg), ascorbic acid (43.09gm/gdm), total phenol (65.13gm/gdm).

5

Controllability of nonlinear stochastic systems with multiple time-varying delays in control

Karthikeyan S., Balachandran K., Sathya M.

International Journal of Applied Mathematics and Computer Science

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2015

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Vol. 25, no. 2

207--215

EN

This paper is concerned with the problem of controllability of semi-linear stochastic systems with time varying multiple delays in control in finite dimensional spaces. Sufficient conditions are established for the relative controllability of semilinear stochastic systems by using the Banach fixed point theorem. A numerical example is given to illustrate the application of the theoretical results. Some important comments are also presented on existing results for the stochastic controllability of fractional dynamical systems.

6

Optimization of growth temperature of multi-walled carbon nanotubes fabricated by chemical vapour deposition and their application for arsenic removal

Mageswari S, Kalaiselvan S, Syed Shabudeen P S, Sivakumar N, Karthikeyan S

Materials Science Poland

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2014

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Vol. 32, No. 4

709--718

EN

Multi-walled carbon nanotubes have been synthesized at different temperatures ranging from 550 ◦C to 750 ◦C on silica supported Fe–Mo catalyst by chemical vapour deposition technique using Cymbopogen flexuous oil under nitrogen atmosphere. The as-grown MWNTs were characterized by scanning electron microscope (SEM), high resolution transmission electron microscope (HRTEM), X-ray diffraction analysis (XRD) and Raman spectral studies. The HRTEM and Raman spectroscopic studies confirmed the evolution of MWNTs with the outer diameter between 20 and 40 nm. The possibility of using as-grown MWNTs as an adsorbent for removal of As (V) ions from drinking water was studied. Adsorption isotherm data were interpreted by the Langmuir and Freundlich equations. Kinetic data were studied using Elovich, pseudo-first order and pseudo-second order equations in order to elucidate the reaction mechanism.

7

The birefringence spectroscopic studies on ferroelectric glycine phosphite (GPI) single crystals

Bhoopathi G., Jayaramakrishnan V., Ravikumar K., Prasanyaa T., Karthikeyan S.

Materials Science Poland

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2013

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Vol. 31, No. 1

1-5

EN

The ferroelectric glycine phosphite single crystals have been grown from aqueous solution by both conventional and Sankaranarayanan-Ramasamy methods. The modified channelled spectrum method has been adopted for spectral dependence of optical birefringence studies over the wavelength range of 480-620 nm, which show that both the crystals exhibit relatively high birefringence values. The photoluminescence excitation studies were carried out for the grown crystals in a wide wavelength range between 300 nm and 600 nm at 224 K. The crystals were also subjected to scanning electron microscopy analysis in order to determine the ferroelectric domain pattern configuration.

8

Constrained controllability of nonlinear stochastic impulsive systems

Karthikeyan S., Balachandran K.

International Journal of Applied Mathematics and Computer Science

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2011

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Vol. 21, no 2

307-316

EN

This paper is concerned with complete controllability of a class of nonlinear stochastic systems involving impulsive effects in a finite time interval by means of controls whose initial and final values can be assigned in advance. The result is achieved by using a fixed-point argument.