70 research outputs found
Synthesis and photophysical studies on 5-ethoxycarbonyl-4-cinnamyl-6-methyl- 3,4-dihydropyrimidine-2(1H)-one in various solvents
The 5-ethoxycarbonyl-4-cinnamyl-6-methyl-3,4-dihydropyrimidine-2(1H)-one (DHPM) was synthesized via Biginelli reaction and was characterized by NMR, IR, UV–Visible absorption and fluorescencespectroscopy. The fluorescence of the compound exhibits red shift from its absorption spectra and correlated with the solvent polarity. The quantum yield of fluorescence of the DHPM was found to vary with solvent polarity. The absorption spectrum of DHPM overlaps significantly with anthracene fluorescence spectrum. Therefore fluorescence quenching experiments were performed in 1,4-dioxane. The fluorescence of anthracene was found to be quenched and quenching is in accordance with Stern-Volmer relation. The Stern-Volmer constant (KSV = 2.52 x 103 M-1) was obtained. The quenching rate constant (kq = 7.145 x 1011 M-1 s-1) was calculated from the fluorescence lifetime of anthracene measured on time resolved fluorimeter (TRF) in absence of DHPM. The fluorescence quenching explained on the basis of energy transfer from anthracene to DHPM derivative. The rate constant as well as efficiency of energy transfer depends on the distance between donor and acceptor and found to be r = 6.39 nm which indicates energy transfer
Effect of soaking time on properties of non-prototype material (CaO-Fe2O3; 21:79 by wt. %)
Discharge of Thermal Storage Tanks via Immersed Baffled Heat Exchangers: Numerical Model of Flow and Temperature Fields
What is the Best Solution to Improve Thermal Performance of Storage Tanks With Immersed Heat Exchangers: Baffles or a Divided Tank?
Effect of baffle and shroud designs on discharge of a thermal storage tank using an immersed heat exchanger
Temperature-induced conformational transition of bovine serum albumin in neutral aqueous solution by reversed-phase liquid chromatography
Compound hydrometeorological extremes across multiple timescales drive volatility in California electricity market prices and emissions
The upward branch of the Brewer-Dobson circulation quantified by tropical stratospheric water vapor and carbon monoxide measurements from the Aura Microwave Limb Sounder
Catalytic C–H to C–M (M = Al, Mg) bond transformations with heterometallic complexes
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