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排序方式: 共有205条查询结果,搜索用时 31 毫秒
31.
Asghar Anam Raman Abdul Aziz Abdul Daud Wan Mohd Ashri Wan Ramalingam Anantharaj Zain Sharifuddin Bin Md 《Research on Chemical Intermediates》2019,45(6):3311-3327
Research on Chemical Intermediates - Hydrogen peroxide (H2O2) is commercially produced by catalytic oxidation of anthrahydroquinone, which is energy-intensive. Electrochemical production of... 相似文献
32.
G. Vijayakumar S. N. Karthick A. R. Sathiya Priya S. Ramalingam A. Subramania 《Journal of Solid State Electrochemistry》2008,12(9):1135-1141
New poly (vinylidenefluoride-co-hexafluoro propylene) (PVDF-HFP)/CeO2-based microcomposite porous polymer membranes (MCPPM) and nanocomposite porous polymer membranes (NCPPM) were prepared by
phase inversion technique using N-methyl 2-pyrrolidone (NMP) as a solvent and deionized water as a nonsolvent. Phase inversion occurred on the MCPPM/NCPPM
when it is treated by deionized water (nonsolvent). Microcomposite porous polymer electrolytes (MCPPE) and nanocomposite porous
polymer electrolytes (NCPPE) were obtained from their composite porous polymer membranes when immersed in 1.0 M LiClO4 in a mixture of ethylene carbonate/dimethyl carbonate (EC/DMC) (v/v = 1:1) electrolyte solution. The structure and porous morphology of both composite porous polymer membranes was examined
by scanning electron microscope (SEM) analysis. Thermal behavior of both MCPPM/NCPPM was investigated from DSC analysis. Optimized
filler (8 wt% CeO2) added to the NCPPM increases the porosity (72%) than MCPPM (59%). The results showed that the NCPPE has high electrolyte
solution uptake (150%) and maximum ionic conductivity value of 2.47 × 10−3 S cm−1 at room temperature. The NCPPE (8 wt% CeO2) between the lithium metal electrodes were found to have low interfacial resistance (760 Ω cm2) and wide electrochemical stability up to 4.7 V (vs Li/Li+) investigated by impedance spectra and linear sweep voltammetry (LSV), respectively. A prototype battery, which consists
of NCPPE between the graphite anode and LiCoO2 cathode, proves good cycling performance at a discharge rate of C/2 for Li-ion polymer batteries. 相似文献
33.
N. Sundaraganesan H. Umamaheswari B. Dominic Joshua C. Meganathan M. Ramalingam 《Journal of Molecular Structure》2008,850(1-3):84-93
The molecular geometry and vibrational frequencies of indole and 5-aminoindole in the ground state have been calculated by using the Hartree–Fock and density functional method with 6-311++G(d,p) basis set. The optimized geometrical parameters obtained by DFT calculations are in good agreement with the experimental values. Comparison of the observed fundamental vibrational frequencies of indole and 5-aminoindole with the calculated results by density functional and Hartree–Fock methods indicates that B3LYP is superior to the scaled Hartree–Fock approach for molecular vibrational problems. The theoretical spectrograms for FT-IR spectrum of 5-aminoindole have been constructed. 相似文献
34.
Vinitha G Ramalingam A Palanisamy PK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,68(1):1-5
Solid-state dye-doped polymers are attractive alternative to the conventional liquid dye solutions. In this paper, nonlinear properties of the dye Pararosanilin has been studied. The third-order nonlinear optical properties of Pararosanilin dye in 1-butanol and dye-doped polymer film were measured by the Z-scan technique using 532 nm diode pumped Nd:Yag laser. This material exhibits negative optical nonlinearity. The dye at 0.4 mM concentration exhibited nonlinear refractive coefficient (n(2) = -6.8 x 10(-8) and -7.11 x 10(-8) (cm(2)/W) in liquid and solid media, respectively), nonlinear absorption coefficient (beta = -7.7 x 10(-4) and -7.93 x 10(-4)cm/W in liquid and solid media, respectively) and susceptibility (chi((3))=3.38 x 10(-6) and 3.53 x 10(-5)esu in liquid and solid media, respectively). These results show that Pararosanilin dye has potential applications in nonlinear optics. 相似文献
35.
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37.
X‐ray photoelectron spectral study was made on the complexes Ni(nmedtc)2( 1 ), [Ni(nmedtc)(PPh3)2]ClO4( 2 ), [Ni‐(nmedtc)(dppe)]BPh4( 3 ) (where nmedtc = N‐methyl, N‐ethanoldithiocarbamate, dppe = 1, 2‐bis(diphenylphosphino)ethane). The nickel 2p3/2 binding energy values for chelated and free phosphine complexes are 854.0 and 854.1 eV which are significantly different from Ni2p3/2 BE value of NiS4 chromophore, indicating the relative dearth of electron density on Ni in NiS2P2 chromophores. The presence of two phosphine groups in NiS2P2 chromophore alleviates the electron density on the metal atom. More electron density is being pulled away from the metal atom in chelates than in the PPh3 analogue. This observation is in line with solution studies by cyclic voltammetry. A one‐electron reduction potential was observed to be the minimum for NiS2P2 chromophores compared to the others. Also the crystal structure of the complex [Ni(pipdtc)(1, 4‐dppb)]ClO4 (pipdtc‐ = piperidinecarbodithioato anion, 1, 4‐dppb = bis(diphenylphosphino)butane) prepared by the reaction between Ni(pipdtc)2, NiCl2�622O, and 1, 4‐dppb in CH3CN‐CH3OH is reported. 相似文献
38.
(1,10-Phenanthroline)bis(piperidinecarbodithioato-S,S′)cadmium(II), [Cd(pipdtc)2(1,10-phen)] (1) and (2,2′-bipyridine)bis(piperidinecarbodithioato-S,S′)cadmium(II), [Cd(pipdtc)2(bipy)] (2) adducts were prepared and the crystal structures are reported. Cd–S and Cd–N distances and the angles subtended at cadmium are almost the same in both complexes but the Cd–S distances in the adducts are longer than those in Cd(pipdtc)2 (3) complexes due to the presence of an additional neutral ligand. Thioureide C–N distance in 1 and 2 are supported by νC–N bands observed at 1471 and 1470 cm−1, respectively. S2p binding energies for the adducts show a significant reduction in value compared to the parent dithiocarbamate indicating the weakening of the Cd–S bond on adduct formation. The observed reduction in binding energy is due to the increased electron density on the metal in the adducts. The cyclic voltammetric study on the complexes also show an increase of electron density on cadmium in the adducts compared to Cd(pipdtc)2. 相似文献
39.
Swaminathan J Ramalingam M Sundaraganesan N 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,71(5):1776-1782
In this work, we report a combined experimental and theoretical study on molecular and vibrational structure of 3-amino-5-hydroxypyrazole (3A5HP). The Fourier transform infrared and Fourier transform Raman spectra of 3A5HP were recorded in the solid phase. The molecular geometry and vibrational frequencies of 3A5HP in the ground state have been calculated by using the density functional method B3LYP with basis sets, 6-311++G(d,p), 6-311+G(3df,2p), 6-311+G(3df,2pd), CC-pVDZ, aug-CC-pVDZ and CC-pVTZ. The optimized geometrical parameters obtained by B3LYP show best agreement with the experimental values. The theoretical spectrograms for FT-IR and FT-Raman spectra of the title molecule have been constructed. 相似文献
40.
S. Ramalingam V. S. Muralidharan A. Subramania 《Journal of Solid State Electrochemistry》2009,13(11):1777-1783
Cu-TiO2 nanocomposites were prepared by electrodeposition method onto copper substrate using an acid copper plating bath containing
dispersed nanosized TiO2. The composition of codeposited TiO2 nanoparticles in the composite coatings was controlled by the addition of different concentrations of TiO2 nanoparticles in the bath solution. The average crystallite size was calculated by using X-ray diffraction analysis and it
was ~32 nm for electrodeposited copper and ~33 nm for Cu-TiO2 composite coatings. The crystallite structure was fcc for electrodeposited copper and Cu-TiO2 nanocomposite coatings. The surface morphology and composition of the nanocomposites were examined by scanning electron microscopy
and energy dispersive X-ray spectroscopy analysis. The effect of TiO2 content on the corrosion and wear resistance properties of the nanocomposite coatings was also presented. The codeposited
TiO2 nanoparticles in the deposit increased the corrosion and wear resistance, which were closely related with TiO2 content in the nanocomposites. The wear resistance and microhardness of the Cu-TiO2 nanocomposite coatings were higher than electrodeposited copper. The corrosion resistance property of the electrodeposited
copper and Cu-TiO2 nanocomposite coatings was evaluated by electrochemical impedance and Tafel polarization studies. Cu-TiO2 composite coatings were more corrosion resistant than electrodeposited copper. 相似文献