Light-capture

Dye release developers are themselves colored molecules, the presence of which in silver halide photographic materials could interfere with light capture by the light-sensitive silver halide. Less light would be available to the sensitizing dyes. Another approach has been reported in which the leuco dye is linked to the coupling-off position of conventional photographic color... 

Apart from individual sites, series of metal ion sites provide electron conduction paths, vital in energy transduction in all organisms and leading to proton transfer, and Mg2+ in chlorophyll is essential for light capture (see Section 4.17). 

Haem, Fe Chlorophyll, Mg Coenzyme B12, Co Factor F-430, Ni Electron transfer in membranes and elsewhere Light capture and transduction in membranes Transfer of methyl, rearrangements of substrates Activation of carbon monoxide... 

Mg2+ Glycolytic pathway (enolase) All kinases and NTP reactions" Signalling (transcription factors) DNA/RNA structures Light capture... 

Fe2+ Reverse citric acid cycle C02 incorporation Signalling transcription factors Control of protein synthesis (deformylation) Light capture... 

McQuade DT, Hegedus AF1, Swager TM (2000) Signal amplification of a turn-on sensor harvesting the light captured by a conjugated polymer. J Am Chem Soc 122 12389-12390... 

Thus for instance, in the sensitization experiments carried out with ethoxy-carbonyl-carbene, dimethoxy-carbonylcarbene, and carbene A, the light capture was generally more than 80% 35> Jn the case of phenyl-cyclopentadienyhdenes the nonstereospecificity clearly depends on the fight capture by the sensitizer... 

Outdoor measurements indicate that the DSC exhibits lower sensitivity to light capture as a function of the incident angle of the radiation, although this needs to be further assessed... 

The first naphtho[a]cyclopropene 68d was also obtained by that route. 3H-indazole was proposed as an intermediate in this reaction 78>. The reaction proceeds equally well from the triplet state of 7. However with acetone light capture from the sensitizer may not have been complete. A trapping of the diradical intermediate 67 to give the known indene 69 by photolysing 7 in dimethyl-acetylene-dicarboxylate (ADC) afforded only a trace of 69. However the yield of 68a was reduced to 40%. Either trapping of 67 was not effective enough or ADC may have acted as quencher. Trapping with furan or cyclopentadiene was also not effective 78a). 

Chemistry is the central science of energy because it involves light capture and conversion with materials and... 

A schematic cycle describing the principle of light capture and energy storage via a photosensitized electron transfer process In an artificial device Is presented In Figure 2. In this system a synthetic sensitizer, S, substitutes for the natural chlorophyll as the light capturing entity. Excitation of the sensitizer, followed by an electron transfer to electron acceptor. A, results In the oxidized sensitizer and a reduced species, A. Oxidation of an electron donor, D, recycles the sensitizer and produces an... 

In this equation, (CH2O) represents carbohydrate, primarily sucrose and starch. The mechanism of photosynthesis is complex and requires the interplay of many proteins and small molecules. Photosynthesis in green plants takes place in chloroplasts (Figure 19.1). The energy of light captured by pigment molecules, called chlorophylls, in chloroplasts is... 

By far the largest number of Ceo-based donor-acceptor systems studied to date utilize porphyrins as antennas for efficient light capture in the visible region of the spectrum [306, 308-310, 324, 329, 341], In the following section systems are presented for which time-resolved and steady-state absorption and emission measurements are available, which document the intramolecular electron transfer processes under a variety of experimental conditions. But we also like to acknowledge the purely synthetic work, for which no experimental data is obtainable [342-351]. 

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