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241.
Anwar Usman Ibrahim Abdul Razak Suchada Chantrapromma Hoong‐Kun Fun A. Sreekanth S. Sivakumar M. R. Prathapachandra Kurup 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):m461-m463
One half of the molecule of the title complex, [Mn(C14H13N4S)2], is related to the other half by a twofold axis passing through the Mn atom. This high‐spin Mn atom is six‐coordinated, in an octahedral geometry, by the azomethine N, the pyridyl N and the thiolate S atom of two planar 1‐(pyridin‐2‐yl)ethanone N(4)‐phenylthiosemicarbazone ligands. In the crystal, the molecules are interconnected by N—H?S and C—H?N interactions, forming a three‐dimensional network. 相似文献
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In(2)O(3) sol-gel thin films made with LaF(3):Ln(3+) (Ln=Er, Nd, and Eu) nanoparticles were prepared and showed sensitized emission of the lanthanide ions after In(2)O(3) matrix excitation. The excitation spectra showed an In(2)O(3) absorption band in addition to the excitation peaks of the lanthanide ions, clearly demonstrating that there is energy transfer from the In(2)O(3) matrix to Ln(3+) (Er(3+), Nd(3+), and Eu(3+)). Similarly, HfO(2) and ZrO(2) sol-gel thin films made with LaF(3):Ln(3+) nanoparticles also showed energy transfer from the semiconductor matrix to the lanthanide ions. 相似文献
244.
Sivakumar K Stalin T Rajendiran N 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,62(4-5):991-999
The absorption and fluorescence spectra of benzanilide (BA) and diphenyl carbazide (DPC) in solvents of different polarities and pH have been analysed. The spectral characteristics of DPC and BA are compared with diphenyl amine molecule. In water and methanol, a dual fluorescence is observed for both DPC and BA molecules. The normal stokes shifted emission originates from a locally excited pi* electronic state and the large stokes shifted band is due to emission from a twisted intramolecular charge transfer (TICT) state. pH studies show that both monocations and monoanions are non-fluorescent. The excited state acidity constants determined by fluorimetric titration and F?rster cycle methods, have been reported and discussed. 相似文献
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247.
K.?Rajammal D.?Sivakumar Navaneethan?Duraisamy K.?Ramesh S.?RameshEmail author 《Ionics》2016,22(9):1551-1556
We demonstrated the effect of ZnO (different wt%)-coated LiMnPO4-based cathode materials for electrochemical lithium ion batteries. ZnO-coated LiMnPO4 cathode materials were prepared by the sol-gel method. X-ray diffraction (XRD) analysis indicates that there is no change in structure caused by ZnO coating, and field emission scanning electron microscopy (FESEM) images depict the closely packed particles. Galvanostatic charge-discharge tests show the ZnO-coated LiMnPO4 sample has an enhanced electrochemical performance as compared to pristine LiMnPO4. The 2 wt% of ZnO-based LiMnPO4 exhibited maximum discharge capacity of 102.2 mAh g?1 than pristine LiMnPO4 (86.2 mAh g?1) and 1 wt% of ZnO-based LiMnPO4 (96.3 mAh g?1). The maximum cyclic stability of 96.3 % was observed in 2 wt% of ZnO-based LiMnPO4 up to 100 cycles. This work exhibited a promising way to develop a surface-modified LiMnPO4 using ZnO for enhanced electrochemical performance in device application. 相似文献
248.
C. Ravi Dhas R. Venkatesh R. Sivakumar A. Moses Ezhil Raj C. Sanjeeviraja 《Ionics》2016,22(10):1911-1926
Electrochromic effect of cobalt oxide thin films was studied as a function of substrate temperature (573–673 K). Tricobalt tetraoxide (Co3O4) thin films were deposited on glass and fluorine-doped tin oxide (FTO) substrates by nebulized spray technique using cobalt nitrate as precursor material. The XRD patterns indicated (311) plane was dominant for all the films irrespective of the deposition temperature. Williamson-Hall (W-H) analysis was made to understand the strain variation in the prepared Co3O4 films under different deposition temperature by employing uniform deformation model (UDM). Scanning electron microscopy images revealed porous morphology for the film prepared at 623 K. The optical parameters such as refractive index (n), extinction coefficient (k), and band gap were derived from UV-visible spectra of Co3O4 films. The electrochromic performance of the deposited Co3O4 films was analyzed through cyclic voltammetry, chronocoulometry, chronoamperometry, and iono-optical studies. 相似文献
249.
Sivanandan K Aathimanikandan SV Arges CG Bardeen CJ Thayumanavan S 《Journal of the American Chemical Society》2005,127(7):2020-2021
Dendrons with a fluorescent probe in a specific location have been synthesized and characterized. Accessibility of guest molecules to each of these layers was then analyzed using an intermolecular photoinduced electron-transfer process. Comparisons of the accessibility among each layer of the dendron and among the generations are provided. 相似文献
250.
T. Dhandayuthapani R. Sivakumar R. Ilangovan C. Gopalakrishnan C. Sanjeeviraja A. Sivanantharaja R. Hari Krishna 《Journal of Solid State Electrochemistry》2018,22(6):1825-1838
Anatase TiO2 thin films with high optical modulation, better reversibility, fast switching time, and enhanced coloration efficiency were prepared by nebulized spray pyrolysis technique. X-ray diffraction study confirmed the formation of anatase phase TiO2 in the present work. This inference was substantiated from the Raman active modes of A1g, 2 B1g, and 3 Eg corresponding to O–Ti–O bond in TiO2. The PL emission peak observed at 400 nm is corresponds to the indirect transition (X1b?→?Γ3) from the conduction band to the valence band. The average reflectance of TiO2 thin films was varied from 31 to 20%. The electrochemical study revealed the excellent performance of TiO2 films with high optical modulation (ΔT?=?61%), fast switching kinetics (t b ?=?1.6 s, t c ?=?2.4 s), good coloration efficiency (100 cm2 C?1), and better reversibility (86%). The efficient electrochromic behavior of films may be due to the smooth microstructure nature, which provides an easy pathway for the diffusion and charge transfer process of Li+ ions in TiO2 film matrix. The fast transfer of Li+ ion was realized from the electrochemical impedance spectroscopic measurement. 相似文献