Stimulated emission and lasing have been demonstrated for chlorophyll a, chlorophyll b, and bacteriochlorophyll a as well as for the Mg-free chlorophyll derivatives pheophytin a and methyl pheophorbide a. Population inversion was obtained by optically pumping with an N(2) laser. For the three chlorophylls, lasing was observed for only the (0,0) vibronic region of the S(1) --> S(0) fluorescence ...

The seasonal cycle of satellite chlorophyll fluorescence observations and its relationship to vegetation phenology and ecosystem atmosphere carbon exchange" (2014). NASA Publications. Paper 158. The seasonal cycle of satellite chlorophyll fluorescence observations and its relationship to vegetation phenology and ecosystem atmosphere carbon exchange a b s t r a c t a r t i c l e i n f o Keywords...

Under conditions (0.2% CO2; 1% O2) that allow high rates of photosynthesis, chlorophyll fluorescence was measured simultaneously with carbon assimilation at various light intensities in spinach (Spinacia oleracea) leaves. Using a stoichiometry of 3 ATP/CO2 and the known relationship between ATP synthesis rate and driving force (Delta pH), we calculated the light-dependent pH gradient (Delta pH)...

We present a high throughput crop physiology condition monitoring system and corresponding monitoring method. The monitoring system can perform large-area chlorophyll fluorescence imaging and multispectral imaging. The monitoring method can determine the crop current condition continuously and non-destructively. We choose chlorophyll fluorescence parameters and relative reflectance of multispec...

As the most severe forestry quarantine disease in several countries, pine wilt (PWD) causes substantial economic losses and poses a significant threat to forest ecosystem. It is necessary find rapid sensitive method for early diagnosis of control development effectively. This paper investigated effect Bursaphelenchus xylophilus (the pinewood nematode; PWN) on chlorophyll fluorescence kinetic cu...

OBJECTIVE To investigate the photosynthesis and fluorescent parameters between Dendrobium officinale and Dendrobium loddigesii, based on which to provide helpful information for the artificial cultivation of these cultivars. METHODS Seeds were placed on the MS medium supplemented with 0.2 mg/L NAA, 2% (w/v) sucrose, 15% (v/v) potato extracts and powered agar (pH 5.8). Two months after germina...

The blue-green alga, Anacystis nidulans, was grown in lights of different colors and intensities, and its absorption and fluorescence properties were studied. Strong orange light, absorbed mainly by phycocyanin, causes reduction in the ratio of phycocyanin to chlorophyll a; strong red light, absorbed mainly by chlorophyll, causes an increase in this ratio. This confirms the earlier findings of ...