Synthesis and electrochemical investigation of hetero bimetallic complexes CoMn2O4 micro rods for novel supercapacitor electrode

M. Murugesan,N. Nallamuthu,R. Ranjithkumar,M. Krishnakumar,P. Devendran,K. Ramesh 대한금속·재료학회 2023 ELECTRONIC MATERIALS LETTERS Vol.19 No.1

Supercapacitors have been emerging tool with high power density in energy storage system. The energy storage capabilityof supercapacitors depends on electrochemical performance of transition metal oxide based electrode materials. Becauseof the co-existence of two metal ions and synergistic eff ects of elements, binary metal oxides, AB 2 O 4 (A or B = Ni, Co,Mo, Mn, and so on), have more active reaction sites and high electrical conductivity than other binary transition metaloxides. To improve the best electrochemical performance, cobalt manganese oxide (CoMn 2 O 4 ) is synthesized via simplehydrothermal method. The CoMn 2 O 4 rod is characterized to analyse its crystalline structure, functional group vibrations,surface morphology and elemental conformations. The electrochemical performance of CoMn 2 O 4 is analysed using cyclicvoltammetry, galvano-static charge–discharge and electrochemical impedance spectrum techniques. The cyclic voltammetryresult reveals that pseudo capacitive behaviour of CoMn 2 O 4 compound. The charge–discharge cycling stability of CoMn 2 O 4rod is analysed in 5 A g −1 up to 10,000 cycles. Asymmetric supercapacitor is fabricated using CoMn 2 O 4 || Activated Carbonwhich also obeys pseudo capacitive behaviour. The energy density is analysed as 28.7 Wh kg −1 at current density 1 mA forasymmetric supercapacitor device.

SOME EXTENSION ON HESITANT FUZZY MAXIMAL, MINIMAL OPEN AND CLOSED SETS

M. SANKARI,C. MURUGESAN The Korean Society for Computational and Applied M 2023 Journal of applied mathematics & informatics Vol.41 No.2

This article presents a novel notion of hesitant fuzzy cleanly covered in hesitant fuzzy topological spaces;moreover two strong hesitant fuzzy separation axioms are investigated. Based on fuzzy maximal open sets few properties of hesitant fuzzy cleanly covered are obtained. By dint of hesitant fuzzy minimal open and fuzzy maximal closed sets two strong hesitant fuzzy separation axioms are extended.

Role of ceria in CO₂ adsorption on NaZSM-5 synthesized using rice husk ash

Hemalatha, P.,Bhagiyalakshmi, M.,Ganesh, M.,Palanichamy, M.,Murugesan, V.,Jang, H.T. Korean Society of Industrial and Engineering Chemi 2012 Journal of industrial and engineering chemistry Vol.18 No.1

Ceria (3, 5, 7, 11, 19wt%) impregnated NaZSM-5 was synthesized and studied for adsorption of CO<SUB>2</SUB>. They were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDS), CO<SUB>2</SUB>-temperature programmed desorption (CO<SUB>2</SUB>-TPD) and Brunauer-Emmett-Teller (BET) techniques. The heat of the reaction (ΔH<SUB>r</SUB>) derived from differential scanning calorimetry (DSC) analysis was 490Btu/lb. XRD analysis showed a decrease in the intensity of patterns with the increase in the ceria loading but crystallization of ceria to larger size was clearly evident for 11 and 19% loading. The surface area decreased for 3 and 5% loading, but increased for 7, 11 and 19% loading illustrating difference in dispersion. The maximum adsorption capacity of CeO<SUB>2</SUB>(5%)/NaZSM-5 was 130mg/g of sorbent. Extraction of silica from the agricultural waste, rice husk, and its use in the zeolite synthesis was an advantage in this study. Hence, from the study it was concluded that ceria impregnated NaZSM-5 could be treated as a novel material for CO<SUB>2</SUB> adsorption, as they were regenerable and recyclable. This study can also be applied to all other zeolites.

ENHANCMENT OF QZSC FED DRIVE PERFORMANCE WITH FPSO CONTROLLER

M. RANJANI,P. MURUGESAN 한국자동차공학회 2015 International journal of automotive technology Vol.16 No.4

The conventional controller suffers from uncertain parameters and non-linear qualities of Quasi-Z Source converter. However they are computationally inefficient extending to optimize the fuzzy controller parameters, since they exhaustively search the optimal values to optimize the objective functions. To overcome this drawback, a Particle Swarm Optimization based Fuzzy controller parameter optimization is presented in this paper. The proposed algorithm is used to find the optimal fuzzy parameters for minimizing the objective functions. The feasibility of the proposed technique has been simulated and tested. The results are bench marked with conventional fuzzy controller and Genetic Algorithm for Quasi-Z Source Converter. The results of the DC/DC Converter for several existing methods illustrate the effectiveness and robustness of the proposed algorithm.

Decolorization of reactive dyes by a thermostable laccase produced by Ganoderma lucidum in solid state culture

Murugesan, K.,Nam, I.H.,Kim, Y.M.,Chang, Y.S. IPC Science and Technology Press ; Elsevier Scienc 2007 Enzyme and microbial technology Vol.40 No.7

Dye decolorizing potential of the white rot fungus Ganoderma lucidum KMK2 was demonstrated for recalcitrant textile dyes. G. lucidum produced laccase as the dominant lignolytic enzyme during solid state fermentation (SSF) of wheat bran (WB), a natural lignocellulosic substrate. Crude enzyme shows excellent decolorization activity to anthraquinone dye Remazol Brilliant Blue R (RBBR) without redox mediator whereas diazo dye Remazol Black-5 (RB-5) requires a redox mediator. Polyacrylamide gel electrophoresis (PAGE) of crude enzyme confirms that the laccase enzyme was the major enzyme involved in decolorization of either dyes. Native and SDS-PAGE indicates that the presence of single laccase with molecular weight of 43kDa. N-Hydroxybenzotriazole (HBT) at a concentration of 1mM was found as the best redox mediator. RB-5 (50mgl<SUP>-l</SUP>) was decolorized by 62% and 77.4% within 1 and 2h, respectively by the crude laccase (25Uml<SUP>-1</SUP>). RBBR (50mgl<SUP>-l</SUP>) was decolorized by 90% within 20h, however, it was more efficient in presence of HBT showing 92% decolorization within 2h. Crude laccase showed high thermostability and maximum decolorization activity at 60<SUP>o</SUP>C and pH 4.0. The decolorization was completely inhibited by the laccase inhibitor sodium azide (0.5mM). Enzyme inactivation method is a good method which averts the undesirable color formation in the reaction mixture after decolorization. High thermostability and efficient decolorization suggest that this crude enzyme could be effectively used to decolorize the synthetic dyes from effluents.

Turbulence, Secondary Clarifier, Concentration, Activated Sludge, Modified Casson Model

Thanapalan Murugesan,Iyyaswami Regupathi,Ponnan Ettiyappan JagadeeshBabu,M. Chitra 한국화학공학회 2010 Korean Journal of Chemical Engineering Vol.27 No.4

Drag reduction is one of the most important techniques for reducing energy consumption in a packed bed contactor. The present work involves an experimental investigation on flow regime transition for air-water system with and without drag reducing agent (DRA), two-phase pressure drop, friction factor and drag reduction using xanthan gum as DRA. Drag reduction was quantified from the two-phase pressure drop data. Based on the present observations it was found that the percentage drag reduction increases with an increase in the concentration of DRA and it is only effective in the range of 300 ppm to 800 ppm. The experimental results indicate that a maximum of 80% drag reduction was achievable using xanthan gum (800 ppm) as DRA. Furthermore, the experimental data were validated with the available literature correlations.

Influence of ball milling time on structural stability and distribution of CNTs in aluminium matrix composites

R. Murugesan,M. Gopal,G. Murali 한양대학교 세라믹연구소 2019 Journal of Ceramic Processing Research Vol.20 No.5

Carbon Nanotubes (CNTs) are considered as an ideal reinforcement to improve the properties of the Aluminium (Al) matrix composites. Even though a significant improvement in mechanical, thermal and electrical properties obtained in Al-CNT composites, there are still several challenges to get uniform dispersion in the matrix and interfacial bonding between CNTs and Al matrix. The objective of the present work is to study the influence of ball milling time on structural stability and distribution of CNTs in Al matrix. The fabricated composite powders morphology like grain size and CNT structural quality were analyzed using Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and Raman spectroscope. It was found that the 6 hrs of ball milling is an effective way to achieve homogeneous distribution of CNTs in Al matrix. The highest hardness value of 77.4 Hv was obtained at 6 hrs ball milling time and subsequently the hardness was reduced to 46.2 Hv at 12 hrs. The reduced hardness of Al-CNT composites may be attributed to lower structural qualities of CNTs with longer milling time. This is evident from the ID/IG values of 0.92 and 1.04 for the 6 hrs and 12 hrs ball milled composites respectively

Effect of Mg/Co on the properties of CdS thin films deposited by spray pyrolysis technique

R. Murugesan,S. Sivakumar,K. Karthik,P. Anandan,M. Haris 한국물리학회 2019 Current Applied Physics Vol.19 No.10

Mg, Co doped and (Mg, Co) co-doped CdS thin films were prepared using chemical spray pyrolysis method. It is observed from the X-ray diffraction study that the deposited film exhibit cubic phase of CdS with preferred orientation along the (111) plane and incorporation of Mg and Co has been confirmed form energy dispersive analysis and XPS analysis as well. The doped and codoped CdS thin films exhibit 1LO and 2LO vibrations as confirmed by Raman spectrum. The core level XPS spectra ensures the incorporation of doping elements precisely. The morphological variations due to the incorporation of Co and Mg in CdS thin films have been observed by FE-SEM. The particle sizes and crystalline nature have been revealed from HRTEM images and corresponding SAED patterns. The co-doped CdS thin films show a significant shift blue in absorption spectrum. Improved magnetic properties have been observed for the co-doped CdS thin films

Hepatoprotective and Curative Properties of Kombucha Tea Against Carbon Tetrachloride-Induced Toxicity

G. S. Murugesan,M. Sathishkumar,R. Jayabalan,A. R. Binupriya,K. Swaminathan,S. E. Yun 한국미생물 · 생명공학회 2009 Journal of microbiology and biotechnology Vol.19 No.4

Photocatalytic oxidation of ceftiofur sodium under UV–visible irradiation using plasmonic porous Ag-TiO2 nanospheres

N. Pugazhenthiran,S. Murugesan,H. Valdés,M. Selvaraj,P. Sathishkumar,P.G. Smirniotis,S. Anandan,R.V. Mangalaraja 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.105 No.-

In this study, 250 nm sized porous anatase TiO2 nanospheres (TiO2 NSPs) composed of 10 nm sized anataseTiO2 nanoparticles are obtained through a green synthetic route and their surfaces have been decoratedwith 3–4 nm sized plasmonic silver nanoparticles (AgNPs). Photoluminescence studies confirm thatthe AgNPs presence on TiO2 NSPs surface effectively inhibits the radiative charge recombination and thusfacilitates charge separation process at the Ag-TiO2 NSPs interface, causing an enhanced photocatalyticactivity. About 92% of the ceftiofur sodium (CFS) antibiotic taken initially is oxidized by Ag-TiO2 NSPsupon 90 min white light irradiation, while Ag loaded Degussa P25 TiO2 nanoparticles effects only 71%CFS oxidation. The synergistic effect given by plasmonic AgNPs and the continuous framework of anataseTiO2 NPs contributes to inhibit the electron-hole recombination in the Ag-TiO2 NSPs. Oxidation productsof CFS in different water sources and their eco-toxicity effects identified through LC-MS and microtoxbioassays,respectively, indicate that the obtained oxidation products are non-toxic compared to pureCFS. Therefore, porous Ag-TiO2 NSPs could be successfully applied in photocatalytic oxidation technologies,exploiting sunlight for the effective removal of pharmaceutical pollutants from wastewater.