Energy-dependent quenching , light

Jahns P and Schweig S (1995) Energy-dependent fluorescence quenching in thylakoids from intermittent light grown pea plants Evidence for an interaction of zeaxanthin and the chlorophyll o/h binding protein CP26. Plant Physiol Biochem 33 683-687... 

Jahns P and Krause GH. (1994) Xanthophyll cycle and energy-dependent fluorescence quenching in leaves from pea plants grown under intermittent light. Planta 1922 176-182... 

Krause GH, Laasch H and Weis E (1988) Regulation of thermal dissipation of absorbed light energy in chloroplasts indicated by energy-dependent fluorescence quenching. Plant Physiol Biochem 26 445-52... 

The LIF technique is extremely versatile. The determination of absolute intermediate species concentrations, however, needs either an independent calibration or knowledge of the fluorescence quantum yield, i.e., the ratio of radiative events (detectable fluorescence light) over the sum of all decay processes from the excited quantum state—including predissociation, col-lisional quenching, and energy transfer. This fraction may be quite small (some tenths of a percent, e.g., for the detection of the OH radical in a flame at ambient pressure) and will depend on the local flame composition, pressure, and temperature as well as on the excited electronic state and ro-vibronic level. Short-pulse techniques with picosecond lasers enable direct determination of the quantum yield [14] and permit study of the relevant energy transfer processes [17-20]. 

These factors are consistent with the 10- to 20-fold decline observed in polyselenide electrolyte in those experiments there also appeared to be little potential dependence of the results (9). Similar thermal quenching data has been reported for dry CdS Te samples irradiated with UV light (10,12,13), electron beams (11), and a particles (19). The temperature dependence of the decline in emission intensity has been linked to the ionization energy of the Te-bound hole, 0.2 eV (10,11,12,13,19). 

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