کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5403028 | 1392749 | 2009 | 7 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Investigation of the fluorescence quenching of 2,3-diazabicyclo[2.2.2]oct-2-ene (DBO) by certain substituted uracils
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The fluorescence quenching of 2,3-diazabicyclo[2.2.2]oct-2-ene (DBO) by a series of uracils has been studied in water and acetonitrile solvents using steady-state and time-resolved fluorescence techniques. The steady-state fluorescence quenching technique has been performed in three different pHs (i.e. 4, 8 and 12). The bimolecular quenching rate constant (kq) increases with increase in pH of uracils. In acidic pH, a pure hydrogen atom abstraction is proposed as the quenching mechanism. This is supported by a pronounced solvent deuterium isotope effect. Electron transfer from the anionic form of uracil to the excited state of DBO is proposed as a mechanism for quenching in basic pH on the basis of highly exergonic thermodynamics obtained from the Rehm-Weller equation. The variation of kq is explained on the basis of the electronic effect of substitution in uracils as well.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Luminescence - Volume 129, Issue 4, April 2009, Pages 382-388
Journal: Journal of Luminescence - Volume 129, Issue 4, April 2009, Pages 382-388
نویسندگان
V. Anbazhagan, R. Renganathan,