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.

Intelligent Position Control of a Vertical Rotating Single Arm Robot Using BLDC Servo Drive

Manikandan R.,Arulmozhiyal R. 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

The manufacturing sector resorts to automation to increase production and homogeneity of products during mass production, without increasing scarce, expensive, and unreliable manpower. Automation in the form of multiple robotic arms that handle materials in all directions in different stages of the process is proven to be the best way to increase production. This paper thoroughly investigates robotic single-arm movements, that is, 360° vertical rotation, with the help of a brushless DC motor, controlled by a fuzzy proportional–integral–derivative (PID) controller. This paper also deals with the design and performance of the fuzzy-based PID controller used to control vertical movement against the limited scope of conventional PID feedback controller and how the torque of the arm is affected by the fuzzy PID controller in the four quadrants to ensure constant speed and accident-free operation despite the influence of gravitational force. The design was simulated through MATLAB/SIMULINK and integrated with dSPACE DS1104-based hardware to verify the dynamic behaviors of the arm.

Effect of stiffened element and edge stiffener in strength and behaviour of cold formed steel built-up beams

Manikandan, P.,Sukumar, S. Techno-Press 2016 Advances in computational design Vol.1 No.2

The aim of this study is to investigate the effect of stiffened element and edge stiffener in the behaviour and flexural strength of built-up cold-formed steel beams. An experimental and analytical analysis of CFS channel sections in four different geometries is conducted, including simple channel sections, a stiffened channel section with or without edge stiffeners. Nonlinear finite element models are developed using finite element analysis software package ANSYS. The FEA results are verified with the experimental results. Further, the finite element model is used for parametric studies by varying the depth, thickness, and the effect of stiffened element, edge stiffener and their interaction with compression flanges on stiffened built-up cold-formed steel beams with upright edge stiffeners. In addition, the flexural strength predicted by the finite element analysis is compared with the design flexural strength calculated by using the North American Iron and Steel Institute Specifications for cold-formed steel structures (AISI: S100-2007) and suitable suggestion is made.

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.

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.

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.

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

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.

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.

Structural characterization of layered Na_0.5Co_0.5Mn_0.5O₂ material as a promising cathode for sodium-ion batteries

Manikandan, Palanisamy,Heo, Seongwoo,Kim, Hyun Woo,Jeong, Hu Young,Lee, Eungje,Kim, Youngsik Elsevier Sequoia 2017 Journal of Power Sources Vol. No.

<P><B>Abstract</B></P> <P>Layered Na<SUB>0.5</SUB>Co<SUB>0.5</SUB>Mn<SUB>0.5</SUB>O<SUB>2</SUB> material is synthesized through a facile mixed hydroxy-carbonate route using (Co<SUB>0.5</SUB>Mn<SUB>0.5</SUB>)<SUB>2</SUB>(OH)<SUB>2</SUB>CO<SUB>3</SUB> precursor and well characterized as a hexagonal layered structure under <I>P</I>6<SUB>3</SUB>/<I>mmc</I> space group. The lattice parameters and unit cell volume (a = 2.8363 Å, c = 11.3152 Å and V = 78.83 Å<SUP>3</SUP>) are calculated by Rietveld refinement analysis. A flaky-bundle morphology is obtained to the layered Na<SUB>0.5</SUB>Co<SUB>0.5</SUB>Mn<SUB>0.5</SUB>O<SUB>2</SUB> material with the hexagonal flake size ∼30 nm. Advanced transmission electron microscopic images are revealed the local structure of the layered Na<SUB>0.5</SUB>Co<SUB>0.5</SUB>Mn<SUB>0.5</SUB>O<SUB>2</SUB> material with contrasting bright dots and faint dark dots corresponding to the Co/Mn and Na atoms. Two oxidation and reduction peaks are occurred in a cyclic voltammetric analysis corresponding to Co<SUP>3+</SUP>/Co<SUP>4+</SUP> and Mn<SUP>3+</SUP>/Mn<SUP>4+</SUP> redox processes. These reversible processes are attributed to the intercalation/de-intercalation of Na<SUP>+</SUP> ions into the host structure of layered Na<SUB>0.5</SUB>Co<SUB>0.5</SUB>Mn<SUB>0.5</SUB>O<SUB>2</SUB> material. Accordingly, the sodium cell is delivered the initial charge-discharge capacity 53/144 mAh g<SUP>−1</SUP> at 0.5 C, which cycling studies are extended to rate capability test at 1 C, 3 C and 5C. Eventually, the Na-ion full-cell is yielded cathode charge-discharge capacity 55/52 mAh g<SUP>−1</SUP> at 0.212 mA and exhibited as a high voltage cathode for Na-ion batteries.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Layered Na<SUB>0.5</SUB>Co<SUB>0.5</SUB>Mn<SUB>0.5</SUB>O<SUB>2</SUB> material synthesized by mixed hydroxy-carbonate route. </LI> <LI> HAAD-STEM and ABF-STEM images revealed the local structure. </LI> <LI> Sodium cell delivered an initial charge-discharge capacity 53/144 mAh g<SUP>−1</SUP> at 0.5 C. </LI> <LI> Stabilized charge-discharge capacity 118/118 mAh g<SUP>−1</SUP> obtained at 3 C. </LI> <LI> Na-ion full-cell fabricated and enabled to attain high voltage region at 0.212 mA. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>