The Inhibitive Effect of Poly(p-Anisidine) on Corrosion of Iron in 1M HCl Solutions

( P. Manivel ),( G. Venkatachari ) 한국부식방식학회(구 한국부식학회) 2005 Corrosion Science and Technology Vol.4 No.2

The Influence of H⁺ and Cl^- Ions on the Corrosion Inhibitive Effect of Poly(para-aminophenol) for Iron in Hydrochloric acid

( P. Manivel ) 한국부식방식학회(구 한국부식학회) 2017 Corrosion Science and Technology Vol.16 No.4

Polymer amines are found to show distinct corrosion inhibition effects in acidic media. The functional groups of organic compounds have a wide role in the physical and chemical properties, for the inhibition efficiency with respect to steric factors, aromaticity, and electron density. The influence of H⁺ ions and Cl^- ions on the corrosion inhibitive effect of poly(p-aminophenol) for iron in hydrochloric acid was studied using electrochemical methods such as impedance, linear polarization, and Tafel polarization techniques. The experiments were conducted with and without the inhibitor, poly(p-aminophenol). The concentration range of H⁺ ions and Cl^- ions are from 1 M to 0.05 M and 1 M to 0.1 M, respectively. With the inhibitor poly(p-aminophenol), this study shows that inhibition efficiency decreases with the reduction of H⁺ ion and Cl^- ion concentrations in aqueous solution. Further, it reveals that the adsorption of an inhibitor on the surface of iron is dependent on the concentrations of H⁺ and Cl^- ions in the solution and the adsorption of inhibitor on the iron surface through the cationic form of amine.

Reduced graphene oxide wrapped ZnFe2O4 nanospheres as selective magnetically recyclable Photocatalysts under visible light irradiation

Aruljothi C.,Manivel P.,Vasuki T. 한국탄소학회 2022 Carbon Letters Vol.32 No.7

Magnetically separable and reusable zinc ferrite/reduced graphene oxide (ZnFe2O4/rGO) nanocomposite has been prepared by hydrothermal method. The results illustrate that the construction of ZnFe2O4 and rGO occur concurrently in a hydrothermal reaction that initiates the formation of rGO-wrapped ZnFe2O4 nanospheres. The morphological and structural features of the ZnFe2O4/rGO nanocomposites reveal that the rGO nanosheets anchored to the ZnFe2O4 sphere act as a self-protective clamping layer to avoid the photo corrosion effect under photo irradiations. The nanocomposites express the soft magnetic behavior with high saturation magnetization under annealing temperature at 300 °C, which may attribute to the well-defined crystalline structure and surface defects. In addition, the GZF 300 nanocomposites exhibit the enhanced photocatalytic degradation over Rhodamine B dye which is 3.4, 1.15, and 1.32 times higher than that of ZF, GZF, and GZF 600 over under visible irradiation in 120 min. The GZF 300 nanocomposites demonstrate their ability to degrade RhB efficiently, even after several photocatalysis cycles with high catalyst recovery by its magnetically separable behavior. The high densities of oxygen defects improvise electron transfer from ZnFe2O4 to rGO and delay the recombination process of the nanocomposite, resulting in enhanced visible photocatalytic activity. The strong magnetic properties of rGO wrapped ZnFe2O4 nanocomposite catalysts the easy separation from the suspension system for multiple usages in water treatment.

Fano manifolds of Calabi-Yau Hodge type

Iliev, A.,Manivel, L. North-Holland Pub. Co 2015 Journal of pure and applied algebra Vol.219 No.6

We introduce and we study a class of odd dimensional compact complex manifolds whose Hodge structure in middle dimension looks like that of a Calabi-Yau threefold. We construct several series of interesting examples from rational homogeneous spaces with special properties.

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.

Multiobjective optimization process of Ti6Al4V alloy using MWCNTs dispersed cutting fluid in turning operation

Senthil Kumar L,Savadamuthu L,Manivel C 한양대학교 세라믹연구소 2022 Journal of Ceramic Processing Research Vol.23 No.4

Turning is one of the precise machining processes, which are widely used at present for many industrial applications. Titaniumalloy Ti6Al4V is widely implemented in the field of aerospace, structural, automotive and biomedical applications. In thisstudy, the most significant factor of Cutting Force, Cutting Temperature and Material Removal Rate is considered the mostresponsible for determining the desirable input factors to the titanium Ti6Al4V alloy in the turning process. Initially, the designof the experiment was conducted for speed, cutting feed, axial depth of cut and the environmental eco-friendly coolant oilconcentration of Multi-Walled Carbon Nanotubes nano-fluid are input parameters of machining process were studied inturning of titanium Ti6Al4V alloy to achieve sustainable production. Desirability Function Analysis was used to predict themathematical model and ANOVA was used to analyze the contribution percentages of the machining parameters. Since theinfluence of the machining parameters of the Cutting Force, Tool Temperature and Material Removal Rate are conflicting innature; the problem was considered a Multi-objective evaluator algorithm-based analysis of the problem. Hence, DesirabilityFunction Analysis was adapted to predict the optimal set of input parameters. The interactive plots reveal that MWCNT’snanofluid improves the result in terms of the maximum rate of removed material with minimum cutting force and cuttingtemperature. Based on multi-objective optimizations of RSM based DFA the optimal results confirm that 1% of MWCNT’sconcentration reduces the cutting temperature and improves the removal of material when MWCNTs are used as cutting fluid.

Facile synthesis of 3-aryl-1-((4-aryl-1,2,3-selenadiazol-5-yl)sulfanyl)isoquinolines

Prabakaran, K.,Khan, F. R.,Jin, J. S.,Jeong, E. D.,Manivel, P. Springer Science + Business Media 2011 Chemické zvesti Vol.65 No.6

Identifification of microRNAs from transcriptome data in gurmar (Gymnema sylvestre)

Kuldeepsingh A. Kalariya,Ram Prasnna Meena,Parmeshwar Lal Saran,Ponnuchamy Manivel 한국원예학회 2019 Horticulture, Environment, and Biotechnology Vol.60 No.3

MicroRNAs (miRNAs) are single-stranded, non-coding, small (~ 22 nt) RNAs that regulate mRNA targets in plants andanimals. Gymnema sylvestre (Retz.) is an important medicinal plant that lacks genomic as well as transcriptomic information. Here, to identify homologous miRNAs, we screened 6028 unique known plant miRNAs against 272,161 unigenes of G. sylvestre (Retz.) generated by paired-end deep transcriptome sequencing. We utilized 76 aligned unigenes for extracting theprecursor sequences in G. sylvestre (Retz.) and identifi ed 16 potential candidate miRNAs belonging to 12 miRNA families. The mean minimal folding free energy index (MFEI) value of these 16 predicted miRNAs was − 0.966, ranging from − 0.653to − 2.37, while the G + C% content varied between 27.3 and 61.9%. Nucleotide composition analysis revealed that cytosinewas the dominant nucleotide in mature miRNAs (26.3%), while uracil was the next most prevalent nucleotide (25.7%), followedby guanine (24.3%) and adenine (23.7%). In most cases (81%), the fi rst position of the 5′ end was occupied by uracilin the identifi ed mature G. sylvestre (Retz.) miRNAs. Diff erential expression of target unigenes revealed that, as comparedto leaf tissue, a total 16 and 12 target unigenes were diff erentially expressed in fl ower and fruit tissues, respectively. Amongthe diff erentially expressed target unigenes were Auxin Response Factors 17-like, Copia-type polyprotein Phytoene synthase2, as well as several encoding unnamed, predicted, uncharacterized, and/or hypothetical proteins. After detailed predictionof miRNAs and their corresponding target unigenes, we report for the fi rst time a total of 13 miRNA and 213 correspondingtarget unigenes in G. sylvestre (Retz.).

A vacuum pressure sensor based on graphene/ZnO nanorod Schottky junction

Sakthivel P.,Ramachandran K.,Malarvizhi M.,Karuppuchamy S.,Manivel P. 한국탄소학회 2024 Carbon Letters Vol.34 No.1

We present a practical vacuum pressure sensor based on the Schottky junction using graphene anchored on a vertically aligned zinc oxide nanorod (ZnO-NR). The constructed heterosystem of the Schottky junction showed characteristic rectifying behavior with a Schottky barrier height of 0.64 eV. The current–voltage (I–V) features of the Schottky junction were measured under various pressures between 1.0 × 103 and 1.0 × 10−3 mbar. The maximum current of 38.17 mA for the Schottky junction was measured at – 4 V under 1.0 × 10−3 mbar. The high current responses are larger than those of the previously reported vacuum pressure sensors based on ZnO nanobelt film, ZnO nanowires, and vertically aligned ZnO nanorod devices. The pressure-sensitive current increases with the vacuum pressure and reaches maximum sensitivity (78.76%) at 1.0 × 10−3 mbar. The sensitivity and repeatability of the Schottky junction were studied by the current–time (I–T) behavior under variation of vacuum pressure. The sensing mechanism is debated from the surface charge transfer doping effect by oxygen chemisorption. The results suggest that this simple graphene/ZnO-NR Schottky junction device may have potential in the fabrication of vacuum pressure sensor with high sensitivity.