The quantum yield
for oxidation of ascorbic acid with methylene green was calculated as a function of concentration of ascorbic acid, concentration of methylene green, temperature, and percentage composition of alcohols such as aqueous methanol, aqueous ethanol and aqueous isopropanol at different temperatures ranging from 303 K to 318 K.
The local minimum in fluorescence quantum yield
dependency on excitation wavelength for freshwater CDOM was found at [[lambda].sub.ex]~270-280nm, where the "blue shift" of CDOM fluorescence emission was typically observed as well [5-7].
Using octacationic Zn(II)-phthalocyanine with singlet quantum yield
of 0.6, they were able to inactivate E.
Miller, "Relative fluorescence quantum yields
using a computer-controlled luminescence spectrometer," Analyst, vol.
Kortshagen, "Silicon nanocrystals with ensemble quantum yields
exceeding 60%," Appl.
The aggregation mechanism together with the possibility of dynamic quenching of excited states by water molecules (that act as quencher) decreases the quantum yield
of fluorescence in the mixtures with higher amount of water .
The structural alterations of the palisade parenchyma of plantlets cultivated at 150 [micro]mol [m.sup.-2] [s.sup.-1] do not reduce their photosynthetic capacity because it does not differ from other parameters, like effective quantum yield
from photosystem II ([DELTA]F/Fm') and increased C[O.sub.2] assimilation, consistent with the dry matter content observed in these plantlets.
Table 3: Effects of different planting patterns and irrigation on maximal quantum yield
(Fv/Fm) in flag leaves of winter wheat in 2008-2009
To determine photosynthetic efficiency differences between the two varieties, quantum yield
of photosynthesis ([phi]) was calculated.
Luminescence intensity and quantum yield
of organic molecules and chromophore dyes when trapped in porous solid matrices are increased by several orders compared to their values in liquid solvent.
In order to maximize the amount of the emitted fluorescence (for nonsaturating illumination), the fluorescence quantum yield
and the fluorescence absorbance have to be as large as possible .
Plants also exhibit numerous physiological adaptations to low irradiance, including increased quantum yield
and reduced dark respiration, light compensation, and saturation points .