On r-dynamic coloring on Mycielskian graphs

GOMATHI C S,MOHANAPRIYA N 장전수학회 2022 Proceedings of the Jangjeon mathematical society Vol.25 No.2

Mycielski graphs are based on transformation from a graph G to a new graph, say μ(G). It is well known that these graphs have same clique number as in the graph G, but the chromatic number is defined as χ(μ(G))=χ(G)+1. The Mycielskian graph G is denoted as μ(G). These Mycielski graphs are colored using r- dynamic coloring which is an proper vertex k-coloring and defined as |c(Neigh(v))|≥min {r, degG(v)}, for each v∈V(G). It is denoted by χr(G). The r-dynamic chormatic number of a graph G is the minutest coloring k of G which is r-dynamic k-colorable. In this paper, the authors investigated the r-coloring of Mycielskian graph of Double Fan graph μ(F2,n), Friendship graph μ(Fn), Pan graph μ(Pn) and Cocktail party graph μ(CPn).

Electrochemical degradation of scarlet red dye from aqueous environment by titanium-based dimensionally stable anodes with SS electrodes

Gomathi, E.,Balraj, B.,Kumaraguru, K. The Korean Society for Applied Biological Chemistr 2018 Applied Biological Chemistry (Appl Biol Chem) Vol.61 No.3

Textile effluents are toxic and carcinogenic materials that exist in the aquatic environment. In this study, the degradation efficiency of commercially available scarlet red dye investigated on TSA-SS Electro Fenton process (EFP) was reported. It is of great interest in the field of environmental engineering to remove dyes from aquatic environment. The influence of operating parameters such as pH (2-9), current density ($0.1-0.5mA/cm^2$), concentration of dye (0.1-0.5 g/L), $H_2O_2$ (0.1-0.5 g/L) concentration and $Fe^{2+}$ concentration (0.01-0.03 g/L) were analyzed by batch system. The optimum degradation conditions were determined as pH-3, current density-$0.4mA/cm^2$, concentration of dye-0.4 g/L, $H_2O_2$ concentration-0.5 g/L and $Fe^{2+}$ concentration-0.025 g/L. These results indicated that the degradation efficiency of scarlet red dye by EFP depends on solution pH and Fenton reagent concentration and a low pH value was favorable for the dye degradation. It has been demonstrated that more than 94% dye removal was obtained at 50 min. Electro Fenton process was also investigated by cyclic voltammetry technologies.

Isolation of Nitrogen Fixing Bacteria from Fungus Termites

GOMATHI, V.,A. RAMALAKSHMI,K. RAMASAMY 한국곤충학회 2005 Entomological Research Vol.35 No.2

Biological nitrogen fixation by the microorganisms in the gut of termites is one of the singularly important symbiotic processes, since termites invariably thrive on nitrogen poor diet. Two isolates of free living aerobic and facultative anaerobic N fixing bacteria were obtained from the guts of fungus cultivating termite, Macrotermes sp. Among the total bacterial isolates from termite gut, the per cents of N fixing aerobes viz., Azotobacter and Beijerinckia spp were 49% and 37% from the salivary gland while facultative N fixing anaerobe viz., Klebsiella and Clostridium contributed (51% and 93%). The free living aerobic bacteria were identified as Azotobacter spp (19×104 CFU mL-1) and Beijerinckia (13.2×104 CFU mL-1) from the salivary gland of the termite; interestingly, foregut, mid gut and hind gut registered a low population of these bacteria. The isolates of Azotobacter were smooth, glistening, vicid in nature, rods, gram negative and cyst forming. Isolates of Beijerinckia sp. produced copious slime, tenacious, rods, gram negative with no cyst formations. Both the isolates emitted green fluorescence and produced acid. Facultative N fixing anaerobes were harbored in the hind gut. The isolates were identified as Klebsiella (20×104 CFU mL-1) and Clostridium pasteurianum 39.1×104 CFU mL-1. Klebsiella were straight rods arranged singly or in pairs, non-motile, gram negative, whereas Clostridium pasteurianum was viscoid, motile with terminal spores. A positive correlation was observed between the extractable of these isolates and soil aggregation. The aggregates formed by the isolates increased soil aeration, porosity, water holding capacity and helped in better plant growth. Thus, the gut microflora of termite, apart from harnessing nitrogen from the atmosphere, also helps improving soil fertility.

Fault Detection and Classification with Optimization Techniques for a Three-Phase Single-Inverter Circuit

Gomathy, V.,Selvaperumal, S. The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.3

Fault detection and isolation are related to system monitoring, identifying when a fault has occurred, and determining the type of fault and its location. Fault detection is utilized to determine whether a problem has occurred within a certain channel or area of operation. Fault detection and diagnosis have become increasingly important for many technical processes in the development of safe and efficient advanced systems for supervision. This paper presents an integrated technique for fault diagnosis and classification for open- and short-circuit faults in three-phase inverter circuits. Discrete wavelet transform and principal component analysis are utilized to detect the discontinuity in currents caused by a fault. The features of fault diagnosis are then extracted. A fault dictionary is used to acquire details about transistor faults and the corresponding fault identification. Fault classification is performed with a fuzzy logic system and relevance vector machine (RVM). The proposed model is incorporated with a set of optimization techniques, namely, evolutionary particle swarm optimization (EPSO) and cuckoo search optimization (CSO), to improve fault detection. The combination of optimization techniques with classification techniques is analyzed. Experimental results confirm that the combination of CSO with RVM yields better results than the combinations of CSO with fuzzy logic system, EPSO with RVM, and EPSO with fuzzy logic system.

Hand arm vibration measurement using micro-accelerometer in different brick structures

Gomathi, K.,Senthilkumar, A.,Shankar, S.,Thangavel, S.,Priya, R. Mohana Techno-Press 2014 Smart Structures and Systems, An International Jou Vol.13 No.6

Hand-Arm Vibration Syndrome (HAVS) is a group of diseases caused by exposure of the hands to vibration while operating the hand held power tools such as road breaker, drilling machine, demolition hammer in construction works. In this paper, area-changed capacitive micro-accelerometer is designed to measure the vibration exposure on worker's hand when operating a drilling machine on various blocks such as clay block, paver block and solid cement block. The design process includes mathematical modelling of micro-accelerometer and simulations are done using INTELLISUITE 8.6. Experimental results are taken for various blocks surfaces using conventional and micro-accelerometer. Comparisons show that usage of area-changed micro-accelerometer for Hand-arm vibration monitoring provides better sensitivity, which in turn reduces the risk of HAVS in workers.

Preparation and Characterization of Conductive Chitosan-Poly[N-(3-trimethoxysilylpropyl)aniline] Hybrid Submicrostructures

Palanisamy Gomathi,김한도,Dhanusuraman Ragupathy,김우년 한국고분자학회 2011 Macromolecular Research Vol.19 No.5

Conducting hybrid submicrostructures composed of chitosan (CS) and silica-based conducting poly[N-(3-trimethoxysilylpropyl)aniline] (PTMSPA) were prepared by graft copolymerization. The spherical and fibrous morphologies of the CS-PTMSPA hybrid submicrostructures could be observed by optical and field emission electron microscopy. Under room temperature conditions, the CS-PTMSPA graft copolymers possessed the uniformly distributed spherical submicroparticles with diameters in the range of ca. 400-1,000 nm. On the other hand, under ice cold conditions (5 ºC), CS-PTMSPA showed the development of randomly oriented fiber bundles. The diameter of a single fiber was in the range of ca. 100-500 nm. These CS-PTMSPA fibers were obtained by a temperaturedriven template-free self-assembly pathway. Spectroscopic and thermal evaluations confirmed that CS-PTMSPA graft copolymer had been prepared by an oxidative polymerization method. The electrochemical performance of the CS-PTMSPA submicrostructures were compared with CS and PTMSPA by cyclic voltammetry with the Fe(CN)6^3-/4-system as a redox marker. The CS-PTMSPA submicrostructures showed high electrical conductivity (difference between the anodic and cathodic peaks = 0.24 and 0.29 V for CS-PTMSPA sphere and fiber, respectively) compared to those of CS (0.14 V) and PTMSPA (0.20 V), which was ascribed to the relatively high surface-to-volume ratios of these submicrostructures.

Electrochemical degradation of scarlet red dye from aqueous environment by titanium-based dimensionally stable anodes with SS electrodes

E. Gomathi,B. Balraj,K. Kumaraguru 한국응용생명화학회 2018 Applied Biological Chemistry (Appl Biol Chem) Vol.61 No.3

Textile effluents are toxic and carcinogenic materials that exist in the aquatic environment. In this study, the degradation efficiency of commercially available scarlet red dye investigated on TSA-SS Electro Fenton process (EFP) was reported. It is of great interest in the field of environmental engineering to remove dyes from aquatic environment. The influence of operating parameters such as pH (2–9), current density (0.1–0.5 mA/cm2), concentration of dye (0.1–0.5 g/L), H2O2 (0.1–0.5 g/L) concentration and Fe2? concentration (0.01–0.03 g/L) were analyzed by batch system. The optimum degradation conditions were determined as pH—3, current density— 0.4 mA/cm2, concentration of dye—0.4 g/L, H2O2 concentration— 0.5 g/L and Fe2? concentration—0.025 g/L. These results indicated that the degradation efficiency of scarlet red dye by EFP depends on solution pH and Fenton reagent concentration and a low pH value was favorable for the dye degradation. It has been demonstrated that more than 94% dye removal was obtained at 50 min. Electro Fenton process was also investigated by cyclic voltammetry technologies.

Antioxidant Activity of Lettuce Tree (Pisonia morindifolia R.Br.) and Tamarind Tree (Tamarindus indica L.) and Their Efficacy in Peanut Oil Stability

Rajkumar Gomathi,Nagarajan Anusuya,Chinnasamy Chitravadivu,Sellamuthu Manian 한국식품과학회 2011 Food Science and Biotechnology Vol.20 No.6

Different solvent extracts of lettuce tree (Pisonia morindifolia R. Br.) and tamarind tree (Tamarindus indica L.) were tested for antioxidant activities. The extracts exhibited effective reducing power and higher radical scavenging efficacy against DPPH and hydroxyl radicals. They also showed metal chelating ability and inhibited peroxidation in the β-carotene/linoleic acid emulsion system. The extracts contained considerable levels of vitamin C,vitamin E, total phenolics, tannins, and total flavonoids estimated through standard spectrophotometric methods. As the acetone and methanol extracts of lettuce and tamarind tree recorded pronounced activities, their protective effects in stabilizing peanut oil were tested in terms of their peroxide value, free fatty acid contents, and p-anisidine values in comparison with the synthetic antioxidants butylated hydroxyanisole and butylated hydroxytoluene. Additionally, the antioxidant activity of the extract-treated oil samples and their phenolic contents were monitored to obtain a complete perspective of the influence of the phenolic compounds in oil stability. Results indicated that the selected leafy vegetables, besides acting as good sources of antioxidants, may serve as substitute for synthetic antioxidants in the stabilization of peanut oil.

A Dietary Antioxidant Supplementation of Jamaican Cherries (Muntingia calabura L.) Attenuates Inflammatory Related Disorders

Rajkumar Gomathi,Nagarajan Anusuya,Sellamuthu Manian 한국식품과학회 2013 Food Science and Biotechnology Vol.22 No.3

The polyphenolic extract from Jamaican cherries (Muntingia calabura L.) was screened for its antioxidant and anti-inflammatory activities. The extract contained considerable amounts of vitamin C (33.6 mg AAE/g extract)and E (14.7 mg TE/g extract), total phenolics (121.1 mg GAE/g extract), flavonoids (173.2 mg RE/g extract), and anthocyanins (82.4 mg CGE/g extract) estimated through standard spectrophotometric methods. The extract also revealed the presence of volatile compounds such as phytol (26.26%), n-hexadecanoic acid (11.97%), cyclopropaneoctanoic acid (10.26%), γ-sitosterol (11.15%), stigmasterol (7.20%),and campesterol (4.47%) as main constituents in the extract. The polyphenol extract demonstrated DPPH radical scavenging activity (IC50 10.6±0.6 μg/mL) and effectively inhibited hydroxyl (IC50 24.9±3.3 μg/mL), and nitric oxide (IC5015.01±1.2 μg/mL) radicals in vitro. The extract also exhibited anti-inflammatory activity in a dose dependent manner by significantly (p<0.01) inhibiting carrageenan induced paw edema and reducing the weight of granuloma in cotton pellet-induced granuloma model in rats. Results indicated that Jamaican cherries could be a potential source of nutrient supplement with anti-inflammatory and antioxidant properties and require promotion of their consumption for public health benefits.

Treatment of textile dye consortium through photo‑electro‑fenton process using graphite‑Ti electrode system and toxicity studies

E. Gomathi,P. Maharaja,Hanumant Singh Rathore,R. Boopathy,Rames C. Panda,T. Senthilvelan,Maruthapillai Arthanareeswari 한국탄소학회 2023 Carbon Letters Vol.33 No.7

The dyeing process is a very important unit operation in the leather and textile industries; it produces significant amounts of waste effluent containing dyes and poses a substantial threat to the environment. Therefore, degradation of the industrial dye-waste liquid is necessary before its release into the environment. The current is focusing on the reduction of pollutant loads in industrial wastewater through remediating azo and thiazine dyes (synthetic solutions of textile dye consortium). The current research work is focused on the degradation of dye consortium through photo-electro-Fenton (PEF) processes via using dimensionally stable anode (Ti) and graphite cathode. The ideal conditions, which included a pH of 3, 0.1 (g/L) of textile dye consortium, 0.03 (g/L) of iron, 0.2 (g/L) of H2O2, and a 0.3 mAcm-2 of current density, were achieved to the removal of dye consortium over 40 min. The highest dye removal rate was discovered to be 96%. The transition of azo linkages into N2 or NH3 was confirmed by Fourier transforms infra-red spectroscopic analysis. PEF process reduced the 92% of chemical oxygen demand (COD) of textile dye consortium solution, and it meets the kinetics study of the pseudo-first-order. The degradation of dye through the PEF process was evaluated by using the cyclic voltammetric method. The toxicity tests showed that with the treated dye solution, seedlings grew well.