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Novel different substitued polypyridine ligands 4-((4-(1H-imidazo[4,5-f][1,10]phenanthroline-2-yl)phenoxy)methyl)benzaldehyde (BA-PPY), (E)-N-(4-((4-(1H-imidazo[4,5-f][1,10]phenanthroline-2-yl)phenoxy)methyl)benzylidene)-pyrene-4-amine (PR-PPY), (E)-N-(4-((4-(1H-imidazo[4,5-f][1,10] phenanthroline-2-yl)phenoxy)methyl)benzylidene)-1,10-phenanthroline-5amine (FN-PPY), 2-(4-(bromomethyl)phenyl)-1H-imidazo[4,5-f][1,10] phenanthroline (BR-PPY), 2-(4-(azidomethyl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (N3-PPY) and triazole containing polypyridine ligand 3,4-bis[(4-(metoxy)-1,2,3-triazole)1-methylphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline)] benzaldehyde (BA-DIPPY) and Ruthenium(II) complexes were synthesized and characterized. Their photopysical properties were investigated. The complexes RuP(PR-PPY), RuB(PR-PPY, RuP(FN-PPY) and RuB(FN-PPY) exhibited a broad absorption bands at 485, 475, 476, and 453 nm, respectively, assignable to the spin-allowed MLCT (dπ–π*) transition. The emission maxima of the pyrene-appended polypyridine ligand PR-PPY was observed at λems = 616 nm and the phenanthroline-appended polypyridine ligand FN-PPY was observed at λems = 668 nm. And the emission maxima of the complexes RuP(PR-PPY), RuB(PR-PPY), RuP(FN-PPY) and RuB(FN-PPY) were observed at λems = 646, 646, 685 and 685 nm, respectively. As seen in fluorescence spectra, the fluorescence intensities of the ligands are higher than their metal complexes. This is because of quenching effect of Ruthenium(II) metal on chromophore groups.  相似文献   
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Aromatic chromophores; pyrene, phenanthrene, anthracene, naphtalene and benzene-tethered Schiff base ligands and their iron(III)/chromium(III) Salen and Saloph capped complexes have been synthesized. Compounds have been characterized by means of FT-IR Spectroscopy, (1)H-NMR Spectroscopy, Magnetic Susceptibility, Elementel Analsis, TG/DTA measurements. Their fluorescence and absorbance properties have been investigated by Luminescence Spectroscopy and UV-vis Spectroscopy. Generally, ligands show an intense excimer fluorescence emissions in acetonitrile-methanol medium while iron(III) and chromium(III) complexes exhibit low fluorescence's. Intensity compared to ligands iron and chromium centers act as an extra chromophore that quench the pyrene, phenanthrene, anthracene, naphtalene and benzene molecules' singlet state. The mechanism of quenching is attributed to a iron (or chromium)-to-pyrene (or phenanthrene, anthracene, naphtalene and benzene) electronic energy transfer process.  相似文献   
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The steady (acoustic) streaming associated with a sphericaldrop displaced from the velocity antinode of a standing waveis studied. The ratio of the particle size to the acoustic wavelengthis treated as small but non-zero, and the solution is developedin the form of a two-term expansion in terms of the correspondingsmallness parameter. The drop viscosity is assumed to be muchhigher than that of the surrounding fluid, which is the casefor a drop in a gas medium. There are essentially three distinctregions where the steady streaming flow is analysed: insidethe drop (internal circulation), in the Stokes shear-wave layerat the surface on the gas side, and the gas outside the Stokeslayer (the outer streaming region). Solutions for the internalcirculation and the outer streaming are obtained in the limitof small Reynolds number. Despite the gas-to-liquid viscosity ratio being small, the outerstreaming may be dramatically affected by the fact that thesphere is liquid as opposed to solid. The parameter that measuresthe effect of liquidity is essentially the viscosity ratio dividedby the relative (to the particle size) thickness of the Stokeslayer. The case of a solid sphere is recovered by letting thisparameter go to zero.  相似文献   
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Novel ruthenium(II)bpy complexes of the phenanthrimidazole-pendant cyclen and cyclam macrocyclic ligands were synthesized as inorganic host molecules. Inorganic host design was planned as a “complex ligand” form because of its tetraaza macrocyclic unit, which has the ability to coordinate to the metals. Photophysical properties and metal selectivity of inorganic hosts RuL1A and RuL2 complex ligands were investigated by UV-vis and fluorescence spectroscopy in aqueous medium. Among Ag(I), Li(I), Na(I), K(I), Cd(II), Cr(II), Fe(II), Hg(II), Ni(II), Pb(II), Zn(II), Cu(II), Mn(III), and Co(III) metal ions, Fe(II) addition causes spectral changes for both RuL1A and RuL2 complex ligands. Electrochemical studies were performed for RuL1B and also for cis-[Ru(bpy) 2 Cl 2 ] . Bimetallic complexes [[Ru(bpy)2([Ni(2-(4-((1,4,8,11-tetraazacyclotetradecan-1-yl)methyl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline])](ClO4)4, RuL1-NiA and [Ru(bpy)2([Ni(2-(4-((1,4,8,11-tetraazacyclotetradecan-1-yl)methyl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline])]Cl4, RuL1-NiB solid complexes were also obtained by the reaction of the RuL1B and Nickel(II).  相似文献   
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CaC2O4真空热分解中,第一阶段生成的CO中47%歧化成CO2和C;第二阶段生成的CO与第一阶段生成的C发生气化反应,发生反应的比例随样品量增加而增大。用CaCO3标定CO后再用CaC2O4标定CO可以排除这些干扰。本文提出了一个对任意气体标定的方法。  相似文献   
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