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361.
Ramakanta Naik Alok Kumar Behera Adyasha Aparimita C. Sripan R. Ganesan 《Phase Transitions》2019,92(1):65-78
In this article, we have demonstrated the optical and structural properties change in Bi/Ag/Se trilayer thin films by the influence of thermal and photon energy. The trilayer films prepared by thermal evaporation technique were annealed and laser irradiated at room temperature. The X-ray diffraction study revealed the Ag2Se phase formation and the surface morphology change is being studied by Field emission scanning electron microscopy. The optical properties of the studied films were characterized by using FTIR spectrophotometer in the wavelength range 400–1200?nm. The reduction of optical band gap by both thermal and laser irradiation is being discussed on the basis of chemical disorderness, defect states and density of localized states in the mobility gap. The Raman shift due to annealing and irradiation supports the changes in the film. The large change in optical band gap in thermal annealing is useful for memory device and waveguide fabrication. 相似文献
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Jordan R. Keith Venkat Ganesan 《Journal of polymer science. Part A, Polymer chemistry》2020,58(4):578-588
Polyzwitterions (polyZIs), macromolecules with repeating ampholytic monomers, are a novel class of materials with attractive properties for battery electrolytes. In this study, we probe the ion transport characteristics and underlying mechanisms in two salt-doped (Li+-TFSI−) polyZIs of similar composition with contrasting zwitterion (ZI) ionic organization: pendant monomers organized via backbone-anion-cation (B-ZI−-ZI+, Motif B) and backbone-cation-anion (B-ZI+-ZI−, Motif C). Within both Motifs B and C, the counterion of the pendant-end ZI moiety shows higher mobility. Similarly, when comparing Li+ or TFSI− across motifs, it is seen that the respective pendant-end counterion possesses higher mobility than its backbone-adjacent counterpart. Furthermore, when comparing counterions to same-position ZI moieties, TFSI− is seen to possess higher mobility than Li+ in each case, a result rationalized by invoking the lower interaction strength between the TFSI− and ZI+. Analysis of ion-transport mechanisms demonstrate that the mobility of countercharges to the pendant-end ZI moiety correlates with the ion-association relaxation timescale, similar to ideas noted in polymerized ionic liquids in past studies. However, the mobility of countercharges to the backbone-adjacent ZI moiety is shown to be correlated with a cage relaxation time, which incorporates the combined effects of frustrated motion due to the presence of the polymer backbone and pendant-end ZI moiety and the higher mobility in a population of lightly ZI-coordinated ions. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 578–588 相似文献
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Maruthachalam Mohanraj Ganesan Ayyannan Gunasekaran Raja Chinnasamy Jayabalakrishnan 《应用有机金属化学》2016,30(7):550-560
Three ruthenium(II) hydrazone complexes of composition [RuCl(CO)(PPh3)2L] were synthesized from the reactions of [RuHCl(CO)(PPh3)3] with hydrazones derived from 4‐methoxybenzhydrazide and 4‐formylbenzoic acid (HL1), 4‐methylbenzaldehyde (HL2) and 2‐bromobenzaldehyde (HL3). The synthesized hydrazone ligands and their metal complexes were characterized using elemental analysis and infrared, UV–visible, NMR (1H, 13C and 31P) and mass spectral techniques. The hydrazone ligands act as bidentate ones, with O and N as the donor sites, and are predominantly found in the enol form in all the complexes studied. The molecular structures of the ligands HL1, HL2 and HL3 were determined using single‐crystal X‐ray diffraction. The interactions of the ligands and the complexes with calf thymus DNA were studied using absorption spectroscopy and cyclic voltammetry which revealed that the compounds could interact with calf thymus DNA through intercalation. The DNA cleavage activity of the complexes was evaluated using a gel electrophoresis assay which revealed that the complexes act as good DNA cleavage agents. In addition, all the complexes were subjected to antioxidant assay, which showed that they all possess significant scavenging activity against 2,2‐diphenyl‐2‐picrylhydrazyl, OH and NO radicals. The in vitro cytotoxic effect of the complexes examined on cancerous cell lines (HeLa and MCF‐7) showed that the complexes exhibit substantial anticancer activity. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
366.
U.N. Roy A. Ingale L.M. Kukreja S. Mishra V. Ganesan K.C. Rustagi 《Applied Physics A: Materials Science & Processing》1999,69(4):385-388
Cadmium sulphide nanocrystals were grown at room temperature (20 °C) under arachidic acid monolayers floating over an aqueous
solution of CdCl2 inside an enclosed Langmuir-Blodgett set-up, through slow infusion of H2S gas. X-ray diffraction spectra suggest an oriented growth of the crystallites. The particle sizes were found to increase
with duration of exposure to the H2S gas. Atomic force microscopy indicated that the particles were nearly circular pellets with uniform morphology throughout.
In Raman spectra, the FWHM of the LO phonon was found to be large (≈20 cm-1) for all the films grown with different exposure times in H2S gas, and was found to reduce to 8 cm-1 after annealing a typical sample at 500 °C for 45 min.
Received: 30 September 1998 / Accepted: 29 March 1999 / Published online: 11 August 1999 相似文献
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Influence of side chain linker length on ion‐transport properties of polymeric ionic liquids 下载免费PDF全文
Jordan R. Keith Santosh Mogurampelly Bill K. Wheatle Venkat Ganesan 《Journal of Polymer Science.Polymer Physics》2017,55(23):1718-1723
We used atomistic molecular dynamics simulations to study the properties of polymerized 1‐alkene‐3‐butylimidazolium‐hexafluorophosphate, a polymerized ionic liquid electrolyte, and characterized the influence of the linear alkene length on the mobility of the hexafluorophosphate ions. Consistent with experimental observations, our simulations indicate that as the alkene length increases, the diffusivity of hexafluorophosphate anion monotonically increases. We demonstrate that such a trend arises from the influence of linker segments on the intermolecular ion hopping rates, which is in turn modulated by intermolecular cationic separation distances. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 1718–1723 相似文献
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