Spin Route Flipping in FeCo/RR-P3HT/ NiFe Organic Spin-Valve Device.

Manikandan Gunasekaran,Dhanalakshmi Dhandapani,Manivel Raja Muthuvel 대한금속·재료학회 2024 ELECTRONIC MATERIALS LETTERS Vol.20 No.2

An organic semiconductor (OSC) is a potential material in spintronics which is posses a long spin diff usion length due toits low spin-orbit coupling and hyperfi ne interaction. Among the OSC P3HT that already exists, in spintronic devices. Inthis report, An organic spin valve (OSV) device was fabricated using Regioregular Poly 3-hexylthiophene-2,5- diyl (RRP3HT). The RR-P3HT was used as a spacer layer, with FeCo and NiFe used as bottom and top electrodes, respectively. The device magnetoresistance (MR) was observed to be a positive MR of 2.9% at 50 K while negative MR of 0.6, 0.4,and 0.014% were observed at 150, 200, and 300 K, respectively. Observed AMR is positive at room temperature for Fecoand NiFe single layer as 0.08 and 0.18%, respectively. The magnetic electrodes were prepared using Ultra High VacuumDC magnetron sputtering, and RR-P3HT was prepared using a spin coater. The magnetic properties of the device werestudied by vibrating sample magnetometer (VSM) analysis. The VSM results conclude that both electrodes are magneticmaterials with diff erent coercive forces. The FeCo and NiFe, both electrodes crystal structures were analyzed from GracingIncidence X-Ray Diff raction (GI-XRD) using Cobalt K alpha. FeCo and NiFe were the Body-Centered Cubic crystalstructures, and the electrode’s JCPDS card numbers are 50–0795 and 37–0474, respectively.

Reactive Black Removal by using Electrocoagulation Techniques: An Response Surface Methodology Optimization and Genetic Algorithm Modelling Approach

Manikandan S.,Saraswathi R. The Korean Electrochemical Society 2023 Journal of electrochemical science and technology Vol.14 No.2

The dye wastewater discharge from the textile industries mainly affects the aquatic environment. Hence, the treatment of this wastewater is essential for a pollutant-free environment. The purpose of this research is to optimize the dye removal efficiency for process influencing independent variables such as pH, electrolysis time (ET), and current density (CD) by using Box-Behnken design (BBD) optimization and Genetic Algorithm (GA) modelling. The electrocoagulation treatment technique was used to treat the synthetically prepared Reactive Black dye solution under batch mode potentiometric operations. The percentage of error for the BBD optimization was significantly greater than for the GA modelling results. The optimum factors determined by GA modelling were CD-59.11 mA/cm², ET-24.17 minutes, and pH-8.4. At this moment, the experimental and predicted dye removal efficiencies were found to be 96.25% and 98.26%, respectively. The most and least predominant factors found by the beta coefficient were ET and pH respectively. The outcome of this research shows GA modeling is a better tool for predicting dye removal efficiencies as well as process influencing factors.

Green synthesis of silver oxide nanoparticles and its antibacterial activity against dental pathogens

Manikandan, Velu,Velmurugan, Palanivel,Park, Jung-Hee,Chang, Woo-Suk,Park, Yool-Jin,Jayanthi, Palaniyappan,Cho, Min,Oh, Byung-Taek Springer-Verlag 2017 3 Biotech Vol.7 No.1

Stiffening evaluation of flat elements towards stiffened elements under axial compression

Manikandan, P.,Arun, N. Techno-Press 2018 Advances in computational design Vol.3 No.1

Thin-walled cross-sections can be optimized to enhance their resistance and progress their behaviour, leading to more competent and inexpensive structural system. The aim of this study is to afford a methodology that would facilitate progress of optimized cold formed steel (CFS) column section with maximum ultimate strength for practical applications. The proposed sections are designed to comply with the geometrical standards of pre-qualified column standards for CFS structures as well as with the number of industrialized and practical constraints. The stiffening evaluation process of CFS lipped channel columns, a five different cross section are considered. The experimental strength and behaviour of the proposed sections are verified by using the finite element analysis (FEA). A series comprehensive parametric study is carried out covering a wide range of section slenderness and overall slenderness ratio of the CFS column with and without intermediate web stiffeners. The ultimate strength of the sections is determined based on the Direct Strength Specification and other design equation available from the literature for CFS structures. A modified design method is proposed for the DSM specification. The results indicate that the CFS column with complex edge and intermediate web stiffeners provides an ultimate strength which is up to 78% higher than standard optimized shapes with the same amount of cross sectional area.

Occupational Heat Stress Impacts on Health and Productivity in a Steel Industry in Southern India

Manikandan Krishnamurthy,Paramesh Ramalingam,Kumaravel Perumal,Latha Perumal Kamalakannan,Jeremiah Chinnadurai,Rekha Shanmugam,Krishnan Srinivasan,Vidhya Venugopal 한국산업안전보건공단 산업안전보건연구원 2017 Safety and health at work Vol.8 No.1

Background: Workers laboring in steel industries in tropical settings with high ambient temperatures are subjected to thermally stressful environments that can create well-known risks of heat-related illnesses and limit workers’ productivity. Methods: A cross-sectional study undertaken in a steel industry in a city nicknamed “Steel City” in Southern India assessed thermal stress by wet bulb globe temperature (WBGT) and level of dehydration from urine color and urine specific gravity. A structured questionnaire captured self-reported heatrelated health symptoms of workers. Results: Some 90% WBGT measurements were higher than recommended threshold limit values (27.2 e41.7C) for heavy and moderate workloads and radiational heat from processes were very high in blooming-mill/coke-oven (67.6C globe temperature). Widespread heat-related health concerns were prevalent among workers, including excessive sweating, fatigue, and tiredness reported by 50% workers. Productivity loss was significantly reported high in workers with direct heat exposures compared to those with indirect heat exposures (c2 ¼ 26.1258, degrees of freedom ¼ 1, p < 0.001). Change in urine color was 7.4 times higher among workers exposed to WBGTs above threshold limit values (TLVs). Conclusion: Preliminary evidence shows that high heat exposures and heavy workload adversely affect the workers’ health and reduce their work capacities. Health and productivity risks in developing tropical country work settings can be further aggravated by the predicted temperature rise due to climate change, without appropriate interventions. Apart from industries enhancing welfare facilities and designing control interventions, further physiological studies with a seasonal approach and interventional studies are needed to strengthen evidence for developing comprehensive policies to protect workers employed in high heat industries.

Antifouling properties of poly(vinylidene fluoride)-incorporated cellulose acetate composite ultrafiltration membranes

Manikandan Gomathy Nainar,Kalidass Jayaraman,Helen Kalavathy Meyyappan,Lima Rose Miranda 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.12

Poly(vinylidene fluoride) (PVDF) was incorporated in Cellulose acetate (CA) to prepare polymeric blend membrane to enhance the antifouling properties and rejection. Blend membranes consist of different concentrations (0, 2.5 and 5.0 wt%) of polyvinylpyrrolidone (PVP), which was the hydrophilic polymer additive and pore forming agent. The existence of membrane functional groups was analyzed by ATR-FTIR spectroscopy. AFM and SEM were conducted to explain the surface morphology of the synthesized blend membranes. Membrane properties were examined by contact angle, porosity and equilibrium water content (EWC). The membrane’s thermal and mechanical properties were determined by performing TGA and tensile test. Membrane performance was assessed by pure water flux (PWF), rejection, antifouling properties using bovine serum albumin (BSA) and Sodium alginate (SA) solution. In this study, CPA-2 membrane showed high PWF of 269.82 L m2 h1, flux recovery ratio (FRR) against BSA and SA was 94% and 92%, respectively. Rejection of BSA and SA was found to be 83% and 86%, respectively. From the results, it was significant that the hydrophilic additive PVP blended membrane ameliorated and showed better results in surface roughness, hydrophilicity, thermal and mechanical stability. Hence, CPA-2 membrane would exhibit less susceptibility to fouling with enhanced PWF, permeability and selectivity.

Available Transfer Capability Enhancement with FACTS Devices in the Deregulated Electricity Market

Manikandan, B.V.,Raja, S. Charles,Venkatesh, P. The Korean Institute of Electrical Engineers 2011 Journal of Electrical Engineering & Technology Vol.6 No.1

In order to facilitate the electricity market operation and trade in the restructured environment, ample transmission capability should be provided to satisfy the demand of increasing power transactions. The conflict of this requirement and the restrictions on the transmission expansion in the restructured electricity market has motivated the development of methodologies to enhance the available transfer capability (ATC) of existing transmission grids. The insertion of flexible AC transmission System (FACTS) devices in electrical systems seems to be a promising strategy to enhance single area ATC and multi-area ATC. In this paper, the viability and technical merits of boosting single area ATC and multi-area ATC using Thyristor controlled series compensator (TCSC), static VAR compensator (SVC) and unified power flow controller (UPFC) in single device and multi-type three similar and different device combinations are analyzed. Particle swarm optimization (PSO) algorithm is employed to obtain the optimal settings of FACTS devices. The installation cost is also calculated. The study has been carried out on IEEE 30 bus and IEEE 118 bus systems for the selected bilateral, multilateral and area wise transactions.

Comparative Study of Two Congestion Management Methods for the Restructured Power Systems

Manikandan, B.V.,Raja, S. Charles,Venkatesh, P.,Mandala, Manasarani The Korean Institute of Electrical Engineers 2011 Journal of Electrical Engineering & Technology Vol.6 No.3

Congestion management is one of the most challenging tasks of a system operator to ensure the operation of transmission system within operating limits. In this paper, cluster/zone method and relative electrical distance (RED) method for congestion management are compared based on the considered parameters. In the cluster/zone method, rescheduling of generation is based on user impact on congestion through the use of transmission congestion distribution factors. In the RED method, the desired proportions of generations for the desired overload relieving are obtained. Even after generation rescheduling, if congestion exists, load curtailment option is also introduced. Rescheduling cost, system cost, losses, and voltage stability parameter are also calculated and compared for the above two methods of congestion management. The results are illustrated on sample 6-bus, IEEE 30-bus, and Indian utility 69-bus systems.

Selective design of binder-free hierarchical nickel molybdenum sulfide as a novel battery-type material for hybrid supercapacitors

Manikandan, Ramu,Raj, C. Justin,Nagaraju, Goli,Pyo, Myoungho,Kim, Byung Chul The Royal Society of Chemistry 2019 Journal of Materials Chemistry A Vol.7 No.44

<P>Recently, binder-free and hierarchical electrode materials have attracted special attention for the rational design of high-energy density hybrid supercapacitors. Herein, we demonstrated binder-free nickel molybdenum sulfide nano-flakes on nickel foam (NMS-Ni) using a facile successive ionic layer adsorption and reaction (SILAR) process for the fabrication of high-performance hybrid supercapacitors. The selective SILAR cycles had a significant effect on the morphology and electrochemical properties of the NMS nanostructures. Specifically, the NMS deposited for 40 cycles (40cyc@NMS-Ni) displayed the maximum areal capacity (<I>C</I>Ac) of 2.8 C cm<SUP>−2</SUP> (2224 C g<SUP>−1</SUP>) at the current density 4 mA cm<SUP>−2</SUP> in a 6 M KOH electrolyte. Furthermore, a hybrid supercapacitor (HSC) was fabricated using 40cyc@NMS-Ni as the positive electrode and N,O-enriched activated carbon (N,O-AC)-coated Ni-foam as the negative electrode, which showed the maximum potential and specific capacitance (<I>C</I>F-cell) of 1.5 V and 111 F g<SUP>−1</SUP>, respectively. Moreover, the device displayed an outstanding specific energy and specific power of 35 W h kg<SUP>−1</SUP> and 1.5 kW kg<SUP>−1</SUP> with an excellent capacitance retention (95%) after 5000 cycles, respectively. Thus, based on the observed results, it can be concluded that the present study demonstrates a route to utilize NMS-based electrodes as a promising material for high-performance energy storage devices.</P>

PRIMORDIAL RADIONUCLIDES DISTRIBUTION AND DOSE EVALUATION IN UDAGAMANDALAM REGION OF NILGIRIS IN INDIA

Manikandan, N. Muguntha,Selvasekarapandian, S.,Sivakumar, R.,Meenakshisundaram, V.,Raghunath, V.M. 대한방사선 방어학회 2001 방사선방어학회지 Vol.26 No.3

The activity concentration of primordial radionuclides i.e., 238U series, 232Th series and 40K, in soil samples collected from Udagamandalam environment, have been measured by employing NaI(Tl) Gamma ray Spectrometer. The absorbed gamma dose rate has also been simultaneously measured by using both Environmental Radiation Dosimeter at each soil sampling location (ambient gamma dose) as well as from the gamma dose derived from the activity concentration of the primordial radionuclides. The results of activity concentration of each radionuclides in soil, absorbed dose rate in air due to soil activity and possible cosmic radiation at each location along with human effective dose equivalent for Udagamandalam environment are presented and discussed.