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71.
Kumaran S. Thirumalai Ko Tae Jo Kurniawan Rendi Li Changping Uthayakumar M. 《Journal of Mechanical Science and Technology》2017,31(8):3949-3954
Journal of Mechanical Science and Technology - This study discusses the development of an Adaptive neuro–fuzzy inference system (ANFIS) model for determining the surface roughness (Ra) during... 相似文献
72.
S. Muthu Kumaran V. Rajendran T. Jayakumar P. Palanichamy P. Shankar Baldev Raj 《Journal of Alloys and Compounds》2008,464(1-2):150-156
Ultrasonic velocities and attenuation measurements have been carried out to characterise the fine scale precipitation events in a slow heat-treated 8090 Al–Li alloy. The alloy was subjected to a slow heating (at the rate of 10 K h−1) to the temperature of 463 K, before and after solution annealing at 803 K for 1 h. The changes in bulk modulus, Young's modulus and Poisson's ratio have been obtained from the ultrasonic velocity data. The variation in hardness and density has been found to be consistent with the changes in velocities and elastic constant. The ultrasonic on-line measurements from 300 to 623 K reveal clearly all the four transitions, including the formation of GP zones at 368 K, formation of δ′ at 470 K, dissolution of δ′ at 532 K and the formation of equilibrium S′ and δ phases at 590 K. The first differential of temperature dependent ultrasonic parameters is found to be particularly effective in clearly diagnosing all the fine scale precipitation/dissolution events. Differentiation between the precipitation and dissolution type reactions is also possible from careful analysis of the first differential plots. 相似文献
73.
An activity-directed fractionation and purification process was used to identify the DPPH (l,l-diphenyl-2-picrylhydrazyl) free radical-scavenging components of Coleus aromaticus Benth. Fresh leaves of C. aromaticus were extracted with water and then separated into hexane, ethyl acetate, and water fractions. Among these, only the ethyl acetate phase showed strong DPPH radical-scavenging activity in vitro, when compared with water and hexane phases. The ethyl acetate fraction was then subjected to separation and purification using Sephadex LH-20 chromatography. Three compounds showing strong DPPH radical-scavenging activity were shown, by spectral methods (1H NMR, 13C NMR, and MS) and by comparison with literature values, to be rosmarinic acid, chlorogenic acid and caffeic acid. In addition, HPLC identification and quantification of isolated compounds were also performed. Rosmarinic acid was found as a major component and principally responsible for the radical-scavenging activity of C. aromaticus. 相似文献
74.
Pattern Analysis and Applications - The fuzzy vault structure, which is a biometric pattern safety process in which the biometric traits are represented as an unordered group, is an example of a... 相似文献
75.
K. Thangaraju R. Kumaran K. Asokan P. Ramamoorthy D. Kanjilal 《Polymer-Plastics Technology and Engineering》2013,52(5):479-482
The effect of swift heavy ion (SHI) irradiation on the optical properties of Tris-(8-hydraxyquinoline) aluminum (Alq3) thin films has been studied. It is confirmed that PL and lifetime of SHI irradiated Alq3 thin films irradiated both at room temperature and low temperature decrease for increasing ion fluences indicating the transfer of excitons energy to unstable cationic Alq3 species. It is also confirmed that PL and lifetime of Alq3 thin films irradiated at low temperature decrease largely compared to that of at the room temperature indicating that a large number of unstable cationic Alq3 species are generated by SHI irradiation. 相似文献
76.
Shanthi G Thanka Kumaran JT Gnana Raj GA Maniyan CG 《Radiation protection dosimetry》2012,149(3):327-332
It is necessary to obtain the transfer factor (TF) of long-lived radionuclides because soil type and vegetation can affect TF. We studied the food crops commonly consumed by the general public of Kanyakumari district of south India. The main focus was on rice, fruits, vegetables and tapioca because the consumption of these is high. The soil to rice TF for the radionuclides, (226)Ra, (232)Th, (238)U and (40) K are 8.8×10(-2), 14.2×10(-2), 5.8×10(-2) and 6.3×10(-2), respectively. The TF of tapioca for (226)Ra, (232)Th, (238)U and (40) K are 6.2×10(-2) , 11×10(-2), 1.9×10(-2) and 8.9×10(-2), respectively. For fruits and vegetables, the TFs are low. In the majority of the crops the non-edible parts accumulate more radionuclides than the edible parts. 相似文献
77.
High rate capable Mn-rich layered Li[Li(x)(Ni0.3Co0.1Mn0.6)1-x]O2 (x = 0.09, 0.11) cathode materials that are fully charged are investigated with respect to stability. Differential scanning calorimetry is used to determine the thermal stability of cathode material compositions together with PVdF binder and a conductive agent by heating from 30 degrees C to 400 degrees C at 10 degrees C/min. In the Li[Li(x)(Ni0.3Co0.1Mn0.6)1-x]O2 (x = 0.09, x = 0.11) cathode materials, the exothermic reaction started at 100 degrees C. Due to thermal runway, a sharp peak was observed at 279.25 degrees C for the material of x = 0.09 with exothermic heat generation of 168.4 J/g. For the Mn-rich cathode material, where x = 0.11, two relatively smaller peaks appeared at 250.72 degrees C and 268.60 degrees C with heat evolution of 71.49 J/g and 93.67 J/g, respectively. These layered cathode materials are thermally stable. The x = 0.09 composition shows huge heat flow occurrence when compared to the x = 0.11. It is concluded from a heat generation analysis that the two Mn-rich cathode materials are thermally stable for lithium rechargeable batteries. 相似文献
78.
Magnetically soft nickel-zinc ferrite (Ni0.5Zn0.5Fe2O4) powder with high saturation magnetization was synthesized by solution combustion route using metal nitrates as precursors and glycine as fuel. The particles were found to have irregular morphology. Three different concentrations of magnetorheological fluids (MRFs) were prepared by dispersing 10, 20 and 40?wt% of these particles in thin silicone oil. The behaviours of the MRFs were studied under steady shear conditions at different applied magnetic field strengths (B). The yield strength (τY) and viscosity (η) of all the MRFs were found to increase with B and particle fill fraction ?, while the response of the MRFs was strongly influenced by the morphology, microstructure and saturation magnetization of the particles. Owing to the low density of the particles, the observed off-state viscosity is high. However, the excellent thermo-oxidative and chemical stabilities of these magnetic oxide particles than metallic magnetic particles make these MRFs dependable for applications in harsh working environments. In addition, the low cost and feasibility of large scale preparation of these magnetic oxides make these MRFs further attractive for industrial applications. 相似文献
79.
A detailed study of the process of crystallization in amorphous Fe25Sc75, Fe28 Sc72 and Fe25Sc45Zr30 alloys has been carried out using differential scanning calorimetry, X-ray diffraction and Mössbauer spectroscopic techniques. The complex multi-stage transformation process in Fe25Sc75 and Fe28Sc72 is understood in terms of polymorphous formation of an intermediate metastable crystalline phase of orthorhombic structure (a = 0.521 nm, b = 0.648 nm and c = 1.212 nm) and of likely Sc3Fe stoichiometry, before final eutectic crystallization to stable Fe2Sc and -Sc. 相似文献
80.
Dhilin Pathayappurakkal Mohanan Nimegha Pathayappurakkal Mohan Nandakumar Selvasudha Saranya Thekkilaveedu Ruckmani Kandasamy 《应用聚合物科学杂志》2021,138(43):51280
The present work deals with the preparation and characterization of lignin based macromolecular polymeric composites and applications thereof. Here lignin is complexed with pectin and/ or gellan gum, to form two different macromolecular green composites LP and LPG. The best ratios screened out through evaluation of nanoparticle characterization and rheology, then confirmed by surface morphology. The superior thermal stability is proved by DSC analysis. The reaction groups involving in complexation are confirmed by FT-IR spectroscopic evaluation where the methoxy or methyl group of lignin interacts with the hydroxyl group of pectin and gellan gum to form nanocomposites. The reduced particle size and surface charge confirm the complexation due to interaction between ionizable functional groups. The applications of these composites are validated by their dye adsorption capacity and anti-microbial properties (after loading of green silver nanoparticles) which proves the multifunctional properties of novel composites. The maximum dye removal efficiency of both composites is independent of initial dye concentration. Dye adsorption capacity is best fitted by Freundlich adsorption isotherms that follow pseudo-second-order adsorption kinetics. The antibacterial study of developed silver nanoparticle loaded and unloaded composites shows wide spectrum activity against E. coli and S. aureus, with higher inhibition efficiency against gram-negative organism. 相似文献