Enhanced Energy Transfer

It is often convenient to have an estimate of an Ko value prior to performing the complex calculation of the overlap integral or labeling of the macromolecnle. Unfortunately  

Ihble 13.3. Representative FSrster OiMnces for Variiws Donor-Acceptor Pairs  

Stiye U. 1978. Hooresceoce ooergy Irawfer s a ipecteDaoopic nice Amm. Rck Atodteite 47 819-846. 

Hfcflei A.. 1974 Theodor Hotel. Bfi Biaun-Ca. Ph Otem. 7k969-97.  

and Bond, L. 1994. Review—lesoneace eno transfer Idelbods and appUeetions, Awit Riocftait. 218 1-13. 

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More convincing proof for a particle-enhanced energy transfer mechanism comes from a study of the concentration dependence of the transfer. Bulk Forster transfer leads to a linear dependence on acceptor concentration with constant donor-to-acceptor ratio. The resonance mechanism would be expected to saturate at (relatively) high concentrations and fall off linearly at very low concentrations. 

L. M. Folan, S. Arnold, and S. D. Druger, Enhanced energy transfer within a microparticle, Chem. Phys. Lett. 118, 322-327 (1985). 

Fig. 16. Structures of the tetracationic porphyrin (TAPP) donor and the tricationic cyanine dye (Cy3+) acceptor used in the polymerization-enhanced energy transfer experiments.

The diffusion equation for long-range energy transfer by the dipole-dipole interaction mechanism which is accompanied by material diffusion has been solved numerically . The theory of enhanced energy transfer between molecules embedded in spherical dielectric particles has been developed for application to dipole-dipole energy transfer taking place between molecules embedded in aerosol droplets. The experimental systems studied involved the use of the dyes coumarin as donor and rhodamine 6G as acceptor. 

The effect of ultrasound is ascribed to promotion of cavitation, which is the rapid generation and collapse of microbubbles within the medium this cavitational collapse results in dramatic pressure and thermal differentials on a microscopic scale, which accelerate mass transport and enhance energy transfer [16]. The enhanced mass transport has also been used to increase the sensitivity of voltammetric analysis [17]. Besides the enhanced mass transport, heating and interfacial cleaning due to the asymmetric collapse of the bubbles at the solid/liquid interface may influence electrolysis. 

A study of the influence of ultrasound on the charging of lead-acid batteries [ 128] showed that there is a great improvement in the performance of these batteries caused by enhancement of ion transport. An increase of 10-22% in battery capacity is obtained in the presence of ultrasound, and even after deducting an estimated increase in capacity due to temperature changes caused by ultrasound, there is still an 8-14% increase in capacity for the battery. The results of the studies led to the conclusion that the improvement in performance. of lead-acid batteries under the action of ultrasound can be attributed to the enhanced energy transfer and accelerated mass transport. 

First, it seems desirable, even prima facie, that we develop an intuition of how chemical reactions occur. For example, molecular orbital theory provides a fair amount of detailed intuition about the energetics of chemical reactions, i.e., when do we expect large activation barriers, when do we expect concerted reactions, what is the effect of an electrophilic substituent on reaction product distributions, etc. A similar intuition has not been available concerning the role of dynamics in chemical reactivity. It is reasonable, as a chemist, to ask how one could enhance energy transfer specifically into the reaction coordinate, thus to make the reaction more efficient and to produce better reaction yields with fewer byproducts. 

Enhanced energy transfer on bilayer membrane was reported [650] (Rg. 

Figure 52 Enhanced energy transfer on a bilayer membrane [650],...

In the green alga, Chlamydomonas reinhardtii, both phosphate and sulfate limitations independently result in a decrease in photosynthetic efficiency (Wykoff et al, 1998 Davies and Grossman, 1998). This is due to the combined effects of increased capacity for xanthophyll cycle-dependent NPQ plus an enhanced energy transfer from PSII to PSI during exposure to nutrient-limited conditions. Thus, the photo-... 

Sun, Q.-C., Mundoor, H., Ribot, J.C., Singh, V., Smalyukh, I.I., and Nagpal, P. (2014) Plasmon-enhanced energy transfer for improved upconversion of infrared radiation in doped-lanthanide nanocrystals. ATano left, 14, 101-106. 

One possible explanation for this enhanced energy transfer could be related to the nature of polymer excitons and the fact that the Si02 Au nanoparticles can exhibit greatly enhanced local field intensities. Since metal nanoparticle resonances have excitation lifetimes of only a few picoseconds, the donor-... 

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