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排序方式: 共有128条查询结果,搜索用时 250 毫秒
111.
M. Asha Jhonsi A. Kathiravan G. Paramaguru C. Manivannan R. Renganathan 《Journal of solution chemistry》2010,39(10):1520-1530
Fluorescence quenching of [Ru(bpy)3]2+ by a series of organic dyes has been investigated by using the steady state fluorescence technique in aqueous medium. The
dyes used are anthraquinone dyes: uniblue, acid blue 129, alizarin, alizarin red S and the azo dyes: congo red, sunset yellow,
methyl orange, tartrazine, acid orange 63, methyl red and erichrome black T. The quenching of [Ru(bpy)3]2+ was found to obey the Stern-Volmer equation and the corresponding Stern-Volmer plots were linear indicating dynamic quenching.
The quenching rate constants (k
q) were calculated from the fluorescence data. The mechanism of quenching was discussed on the basis of the quenching rate
constants as well as the reduction potential of dyes. The electron transfer mechanism has been proved by the calculation of
Gibbs energy changes (ΔG
et) by applying the Rehm-Weller equation. 相似文献
112.
113.
Nycholat CM McBride R Ekiert DC Xu R Rangarajan J Peng W Razi N Gilbert M Wakarchuk W Wilson IA Paulson JC 《Angewandte Chemie (International ed. in English)》2012,51(20):4860-4863
Human influenza viruses are proposed to recognize sialic acids (pink diamonds) on glycans extended with poly-LacNAc chains (LacNAc=(yellow circle+blue square)). N- and O-linked glycans were extended with different poly-LacNAc chains with α2-3- and α2-6-linked sialic acids recognized by human and avian influenza viruses, respectively. The specificity of recombinant hemagglutinins (receptors in green) was investigated by using glycan microarray technology. 相似文献
114.
Perovskite Bi1−x
Y
x
FeO3 (0.0 ≤ x ≤ 0.1) oxides were prepared by a citrate-gel method. The crystal structure examined by X-ray powder diffraction indicates
that the samples were single-phase and crystallize in a rhombohedral (space group, R-3c no. 161) structure. The structural phase transition from rhombohedral to orthorhombic phase was observed at x = 0.10. Increase in magnetization was observed as a result of Y doping. The optical band-gap of (Bi, Y)FeO3 materials were determined. The observed increase in magnetization and low band-gap of (Bi, Y)FeO3 ceramics position them for potential magenotoelectric and photocatalytic applications, respectively. 相似文献
115.
M. Vijay K. Ramachandran P.V. Ananthapadmanabhan B. Nalini B.C. Pillai Federica Bondioli A. Manivannan R.T. Narendhirakannan 《Current Applied Physics》2013,13(3):510-516
Nanocrystalline TiO2 powder is synthesized using a novel reactive plasma process in which the precursor TiH2 powder is oxidized through thermal plasma in-flight route to generate nanocrystalline TiO2 powder. The synthesized powder consists of nano-sized TiO2 particles, both anatase and rutile phases, in which anatase is the predominant phase. An additional feature of the plasma synthesized TiO2 powder is the higher surface concentration of Ti3+ state and hydroxyl group that enhance its photocatalytic activity. The photocatalytic inactivation of Gram-positive Enterococcus and Gram-negative Klebsiella bacteria is studied using the plasma synthesized TiO2 nanopowder with 365 nm ultraviolet (UV) light. The mechanism behind the photocatalytic disinfection of bacteria is discussed. The plasma synthesized TiO2 nanopowder catalyst is found effective in killing Enterococcus and Klebsiella. The results corroborated that the plasma synthesized TiO2 powder can be used for waste water treatment and water purification. 相似文献
116.
Dhanuskodi S Manivannan S Kirschbaum K 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,64(2):504-511
1-Ethyl-2,6-dimethyl-4-hydroxy pyridinium chloride dihydrate and bromide dihydrate salts have been synthesized and their single crystals were grown by the slow evaporation of aqueous solution at 30 degrees C. The grown crystals were characterized by elemental analysis, FT-NMR and FT-IR techniques to confirm the formation of the expected compound. Optical transmittance window in aqueous solution was found to be 275-1100 nm by UV-vis-NIR technique. Thermogravimetric and differential thermal analyses reveal thermal stability and the presence of two water molecules in the crystal lattices. The crystal structure of chloride salt was also determined by X-ray diffraction method. 相似文献
117.
Jeyakumari AP Dhanuskodi S Manivannan S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,63(1):91-95
L-Arginine tetrafluoroborate (C6H15N4(+)O2BF4(-)) is a semiorganic crystalline material exhibiting second harmonic generation (SHG) down to the UV region. The material was synthesized and characterized by elemental analysis, FT-NMR and FT-IR spectra. The lower cutoff wavelength was found to be 270 nm, with a good optical transmittance window covering UV-vis-NIR region. The thermal stability of the compound was determined by TG-DTA curves. The powder SHG efficiency was measured using a Q-Switched Nd:YAG laser assembly by a modified Kurtz and Perry powder technique and its phase matching property was established. 相似文献
118.
119.
G. Filoti V. Kuncser H. Franke T. Kardinahl G. Manivannan 《Journal of Radioanalytical and Nuclear Chemistry》1995,190(2):315-320
The ferric chloride doped polymers change their refractive index under UV irradiation. The Fe:PVA is sensitive to ferric chloride concentration, molecular weight of PVA, and recording beam power. By Mössbauer investigations we tried to correlate the Fe2+/Fe3+ ratio, as well as the temperature dependence of the energetical parameters with the assumed mechanisms which involve both the valence state of iron and a cross-linking reaction of PVA matrix. 相似文献
120.
TiO2 nanocrystals doped with 1%, 5% and 10% Co/TiO2 and 10% M (M=Fe, Mn and Ni) were prepared by the sol–gel technique and characterized using X-ray diffraction and SQUID. The
as-prepared samples are found to be paramagnetic at room temperature, with the magnetic susceptibility following the Curie–Weiss
law in the investigated range of 2–370 K. However, transformation from paramagnetism to room-temperature ferromagnetism (RTFM)
for the 5% Co/TiO2 was observed by hydrogenating the sample at 573 K while the 1% sample remained paramagnetic. As the percentage of Co was
increased from 5% to 10% the Curie temperature increased from 390 K to 470 K determined via extrapolation. Transformation
from paramagnetism to room-temperature ferromagnetism (RTFM) was also observed by hydrogenation of 10% Fe/TiO2 at 573 K for 6 h. X-ray diffraction of the hydrogenated sample shows only single phase TiO2 structure suggesting that the observed RTFM may be intrinsic but magnetic studies may suggest the possibility of Fe nanoparticles. 相似文献