Manganese-titanium-oxide-hydroxide-supported palladium nanostructures - A facile electrocatalysts for the methanol, ethylene glycol and xylitol electrooxidation

Kannan, R.,Kim, A.R.,Nahm, K.S.,Yoo, D.J. Pergamon Press ; Elsevier Science Ltd 2016 International journal of hydrogen energy Vol.41 No.16

<P>The formation of organic poisoning intermediate species during fuel (alcohol) oxidation over a noble-metal catalyst electrode retards the electrooxidation reaction. To address this problem, we report the synthesis of a manganese-titanium-oxide-hydroxide-supported palladium nanocatalyst (Pd@MTOH), whereby a hydrothermal reaction is followed by an in situ reduction process. The physical characterizations confirm the formation of Pd NPs and a mixed-valance MTOH. The voltammetric-study results for the Pd@MTOH show a high level of electrochemical activity toward alcohol (methanol, ethylene glycol, and xylitol), and oxidation toward the Pd@MnOOH and Pd@C electrodes. At the Pd@MTOH electrode, the poisonous intermediate species that were formed during alcohol electrooxidation were successfully removed at a higher forward potential; the excellent catalytic activity, better intermediate tolerance, and sound long-term stability of the Pd@MTOH electrode can be credited to the uniform dispersion of the Pd NPs and the support (MTOH). This work outlines a facile method for the fabrication of a catalyst with a high electrochemical performance and great potential in alcohol fuel-cell applications. Copyright (C) 2016, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.</P>

Fuzzy error matrix in clssification problems

S. R. Kannan 한국전산응용수학회 2008 Journal of applied mathematics & informatics Vol.26 No.5

This paper concerns a new method called Fuzzy Supervised Method for error matrix, the method has developed based on Adoptive Neuro- Fuzzy Inference Systems(ANFIS). For the performance point of view initially the new method tested with trial data and then this paper applies the proposed method with real world problems. So that this paper generated 1000 random error matrices in programming language [R] and then it tests the new proposed method for the error matrices. The results of Fuzzy Supervised Method given in terms of Kappa Index and Congalton Accuracy Indexes, and performance of Fuzzy Supervised Method has evaluated by using Pearson’s test. This paper concerns a new method called Fuzzy Supervised Method for error matrix, the method has developed based on Adoptive Neuro- Fuzzy Inference Systems(ANFIS). For the performance point of view initially the new method tested with trial data and then this paper applies the proposed method with real world problems. So that this paper generated 1000 random error matrices in programming language [R] and then it tests the new proposed method for the error matrices. The results of Fuzzy Supervised Method given in terms of Kappa Index and Congalton Accuracy Indexes, and performance of Fuzzy Supervised Method has evaluated by using Pearson’s test.

Production based Scheduling Method for Linear Construction in Road Projects

S. R. Kannan,R. Senthil 대한토목학회 2014 KSCE JOURNAL OF CIVIL ENGINEERING Vol.18 No.5

Scheduling of road projects has always been a challenging endeavor in the construction industry as project durations are quite often unpredictable. It depends on the production rates of individual activities which are governed by factors such as availability of resources, environmental and geographical conditions. The current trend in road project scheduling is based on productivity of a certain item of work with a defined crew as resource. Practically, as these production rates are not achieved as per plan, an attempt has been made in this work to propose a simple model to estimate road project durations utilizing probable production rates of activities. A simulation model attempted to arrive at probable production rates of these activities has indicated a wide range of values that cannot lead to accurate time estimates. A more specific range of production rate estimates have been arrived adopting Delphi process to account for factors mainly within the purview of constructors. The basic framework for time estimates has been proposed by adopting Linear Scheduling Method (LSM) for scheduling due to limitations of network techniques in road works. A simple flowchart model of the time estimate method has been presented incorporating probable production rates defining crews and buffer distances.

FUZZY ERROR MATRIX IN CLSSIFICATION PROBLEMS

Kannan, S.R.,Ramathilagam, S.R. Korean Society of Computational and Applied Mathem 2008 Journal of applied mathematics & informatics Vol.26 No.5

This paper concerns a new method called Fuzzy Supervised Method for error matrix, the method has developed based on Adoptive Neuro- Fuzzy Inference Systems(ANFIS). For the performance point of view initially the new method tested with trial data and then this paper applies the proposed method with real world problems. So that this paper generated 1000 random error matrices in programming language [R] and then it tests the new proposed method for the error matrices. The results of Fuzzy Supervised Method given in terms of Kappa Index and Congalton Accuracy Indexes, and performance of Fuzzy Supervised Method has evaluated by using Pearson's test.

One-pot synthesis and electrocatalytic performance of Pd/MnOx/graphene nanocomposite for electrooxidation of ethylene glycol

Kannan, R.,Kim, A.R.,Nahm, K.S.,Yoo, D.J. Pergamon Press ; Elsevier Science Ltd 2015 International journal of hydrogen energy Vol.40 No.35

In this study, low-loading palladium nanoparticles (Pd NPs) were prepared on a graphene oxide-manganese oxide (GR/MO) support using a one-pot, eco-friendly ''green'' process. The GR/MO-Pd nanocomposite was characterized by powder X-ray diffraction, Raman, scanning microscopy and transmission electron microscopy. The elemental composition was determined using energy dispersive X-ray spectroscopy, and the electronic state of the materials was characterized by X-ray photoelectron spectroscopy. The GR/MO-Pd nanocomposite exhibited high electrocatalytic activity towards ethylene glycol oxidation in alkaline medium. The GR/MO-Pd electrode demonstrated a forward anodic peak current density of 3.8 mA/cm<SUP>2</SUP>, which was higher than both MO-Pd and GR-Pd electrodes. This excellent catalytic activity, low onset potential, better intermediate tolerance and good long-term stability of the GR/MO-Pd electrode could be attributed to the uniform dispersion of Pd NPs over the GR/MO support. This work outlines a new method for simple, fast and eco-friendly fabrication of a catalyst with high electrochemical performance and potential in alcohol fuel cell applications.

3D graphene-mixed metal oxide-supported carbon?palladium quantum dot nanoarchitectures - A facile bifunctional electrocatalyst for direct ethylene glycol fuel cells and oxygen evolution reactions

Kannan, R.,Kim, A.R.,Kim, J.S.,Yoo, D.J. Pergamon Press ; Elsevier Science Ltd 2016 International journal of hydrogen energy Vol.41 No.40

<P>Nanoarchitectured carbon-palladium quantum dot (C-Pd)-supported manganese-titanium oxide/3D graphene (MTOx-3DG) catalyst is developed using a two-step process, for ethylene glycol fuel cells and oxygen evolution reactions. About 10 nm-sized carbon shell and a 5 nm-sized Pd catalyst over an MTOx-3DG support is established by the facile green chemical approach. The C-Pd-MTOx-3DG nanoarchitectured catalyst possesses excellent electrocatalytic activity with the peak current density of 23.8 mA/cm(2) for ethylene glycol electrooxidation. In addition, MTOx-3DG support material helps to remove the poisonous intermediates formed during the ethylene glycol electrooxidation. We addressed this point by suitable method in which about 80% of the poisonous compounds are removed, with the help of a supporting material at higher forward potential regions. In addition to that the formation of Pd adatoms and synergism of mixed metal atoms helped to effectively oxidize the fuel. The physical and chemical analyses show that the prepared C-Pd-MTOx-3DG electrocatalyst is nanostructured, with excellent catalytic activity, better intermediate tolerance, and sound long-term stability of the catalyst, attributed to the uniform dispersion of the Pd QDs and excellent interaction between the noble metal catalyst and the support. The present study sketches a simple and novel electrocatalyst for direct ethylene glycol fuel cells. (C) 2016 Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.</P>

Mononuclear transition metal complexes with sterically hindered carboxylate ligands: Synthesis, structural and spectral properties

Kannan, S.,Venkatachalam, G.,Lee, H.J.,Min, B.K.,Kim, W.,Koo, E.,Do, Y.R.,Yoon, S. Pergamon Press 2011 Polyhedron Vol.30 No.2

The metal coordination geometry in the active site of metalloproteins are very different from the one of small inorganic complexes, due to the inflexibility of the ligand set from amino acid side chains different from freely moving ligand set in synthesis. Using the sterically hindered 2,6-di-(p-fluorophenyl)benzoate(L) ligand, a series of mononuclear Co(II), Ni(II) and Cu(II) complexes of general formula [M(L)<SUB>2</SUB>(Hdmpz)<SUB>2</SUB>] (where, Hdmpz=3,5-dimethyl pyrazole) have been synthesized and characterized by the variety of spectroscopic methods. A distorted octahedral geometry in case of nickel, tetrahedral geometry for cobalt and square pyramidal in copper was observed in the X-ray studies, which also revealed that the uncoordinated oxygen atom of the carboxylate group forms intramolecular hydrogen bonding with the N-H group of the coordinated 3,5-dimethylpyrazole in case of cobalt and copper.

Effects of bilateral superficial cervical plexus block on sevoflurane consumption during thyroid surgery under entropy-guided general anesthesia: a prospective randomized study

Sudheesh Kannan,Nethra S Surhonne,Chethan Kumar R,Kavitha B,Devika Rani D,Raghavendra Rao R S 대한마취통증의학회 2018 Korean Journal of Anesthesiology Vol.71 No.2

Background: Bilateral superficial cervical plexus block (BSCPB) provides good postoperative analgesia, but its effect on anesthetic consumption is unknown. This study evaluated the effects of BSCPB on sevoflurane consumption during thyroid surgery. Methods: Fifty patients were randomly allocated into groups A and B of 25 each in this prospective double-blind study. Group A received BSCPB with 20 ml 0.25% bupivacaine, whereas group B received 20 ml saline immediately before entropy-guided general anesthesia. Intraoperative hemodynamic parameters, end-tidal sevoflurane concentration, minimum alveolar concentration, and sevoflurane consumption were recorded. Postoperative pain was assessed using a visual analog scale, and the time of the first request for analgesia was noted. All side effects were recorded. Results: Demographics were comparable. Mean sevoflurane consumption [for 30 min: group A = 7.2 (1.1) ml, group B = 8.8 (2.0) ml, P = 0.001; for 60 min: group A = 13.5 (1.7) ml, group B = 16.5 (3.9) ml, P = 0.002] and mean end-tidal sevoflurane concentration [for 30 min: group A = 1.2% (0.2%), group B = 1.4% (0.2%), P = 0.008; for 60 min: group A = 1.2% (0.1%), group B = 1.4% (0.2%), P = 0.010] were significantly lower in group A. Patients in group A had a longer duration of analgesia [361.6 (79.5) min vs. 151.0 (60.2) min, P < 0.001] compared to those in group B. Conclusions: Preinduction BSCPB during thyroid surgery significantly reduced sevoflurane consumption and increased the duration of postoperative analgesia.

Facile tailor-made enhancement in proton conductivity of sulfonated poly(ether ether ketone) by graphene oxide nanosheet for polymer electrolyte membrane fuel cell applications

Jang, H. R.,Yoo, E. S.,Kannan, R.,Kim, J. S.,Lee, K.,Yoo, D. J. Springer Science + Business Media 2017 Colloid and Polymer Science Vol.295 No.6

<P>Sulfonated poly(ether ether ketone) and graphene oxide nanocomposite-based polymer electrolyte membranes were prepared by facile solution casting method, and their applications for single cell were investigated. The degree of sulfonation played an important role in the proton conductivity of polymer electrolytes. Thus, we studied both the low and high degree of sulfonated poly ether ether ketones (SPEEKs) as composite with amphiphilic graphene oxide nanosheets (GNSs). The obtained results on water uptake and swelling profile showed that the physical and chemical properties of polymer electrolytes significantly improved after insertion of GNS. Morphological properties of the fabricated membranes were investigated with field emission scanning electron microscopy (FE-SEM), and the equal dispersion of GNS sheets throughout the cross section of polymer matrix was observed. The temperature-dependent conductivity reveals that SPEEK-GNS composite showed improved proton conductivity compared to pure SPEEK, because of the high degree of dispersion of GNS thus facilitated the extension of proton transport channels. Best enhancement in conductivity is observed for composite membrane containing 1.0 wt% of GNS, i.e., 149 mS cm(-1).</P>

A Random Forest Model Based Pollution Severity Classification Scheme of High Voltage Transmission Line Insulators

Kannan, K.,Shivakumar, R.,Chandrasekar, S. The Korean Institute of Electrical Engineers 2016 Journal of Electrical Engineering & Technology Vol.11 No.4

Tower insulators in electric power transmission network play a crucial role in preserving the reliability of the system. Electrical utilities frequently face the problem of flashover of insulators due to pollution deposition on their surface. Several research works based on leakage current (LC) measurement has been already carried out in developing diagnostic techniques for these insulators. Since the LC signal is highly intermittent in nature, estimation of pollution severity based on LC signal measurement over a short period of time will not produce accurate results. Reports on the measurement and analysis of LC signals over a long period of time is scanty. This paper attempts to use Random Forest (RF) classifier, which produces accurate results on large data bases, to analyze the pollution severity of high voltage tower insulators. Leakage current characteristics over a long period of time were measured in the laboratory on porcelain insulator. Pollution experiments were conducted at 11 kV AC voltage. Time domain analysis and wavelet transform technique were used to extract both basic features and histogram features of the LC signal. RF model was trained and tested with a variety of LC signals measured over a lengthy period of time and it is noticed that the proposed RF model based pollution severity classifier is efficient and will be helpful to electrical utilities for real time implementation.