Energy Transfer Effects

Chattoraj M, Chung DD, Paulson B et al (1994) Mediated electronic energy transfer effect of a second acceptor state. J Phys Chem 98 3361-3368... 

Hartmann P., Photochemically induced energy-transfer effects on the decay times of ruthenium complexes in polymers, Anal. Chem. 2000, 72(13) 2828-2834. 

Energy transfer effects may play some part in the kinetics of photodimerization, photooxidation, or concentration quenching of fluorescence, although it is not yet possible to give an estimate of their importance. 

Some typical 60Co gamma radiation dose requirements for fully polymerizing several concrete-polymer systems are given in Table II. There is some evidence (5) that a lower dose is required to polymerize monomer in concrete than monomer alone. This may be attributed to energy transfer effects in the heterogeneous concrete-monomer system. 

Swiatla-Wojcik D, Buxton GV (1998) Modelling of linear energy transfer effects on track core processes in the radiolysis of water up to 300°C. J Chem Soc Faraday Trans 94 2135-2141 Sychev AY, Isak VG (1995) Iron compounds and the mechanisms of the homogeneous catalysis of the activation of O2 and H2O2 and of the oxidation of organic substrates. Russ Chem Rev 12 1105-1129... 

This same large energy transfer effect has been found to occur in simulations of h in some CO2 clusters (R. Parson, personal communication). 

We attributed also to injection the dominant fast component of the fluorescence on the semiconductors. The minor slow component was attributed to molecules adsorbed at a few semiconductor surface sites where injection cannot take place. The rate constants kg and k were estimated from the data obtained at the lowest concentration (10 M), so as to minimize energy transfer effects. The values = r2(dry) = 3.1 ns and kj = 0 were used in [5] to derive kg = 3.2 x 10 s. This kg value and Tf = Ti were then used in [5] and in [7] to derive kj = 2.1 x 10 s and = 0.88 both for Sn02 and for InjOj. This kj value is six times lower than that estimated from our steady-state measurements for In203 and three times higher than calculated by Itoh et al. (16) for Sn02. Because the time-resolved measurements are much more direct, we consider this kj value to be more reliable than those derived from steady-state measurements. 

Further evidence of Forster-type energy-transfer effects has been obtained for several excited triplet-state donors and several ground-state doublet nitroxyl radicals. Critical transfer distances of the order of 12—20 A were measured and were on good agreement with calculated values. 

Hence, kp values ue activities which are normalized with respect to monomer and catalyst concentrations, and these values can be used to compare activities for different catalysts or for the same catalyst in different reutors or at different monomer concentrations. If the intrinsic rate of polymerization is first order with respect to monomer concentration, as assumed in Equation 1, and if mass and energy transfer effects are negligible, then the kp, for fixed co-catalyst concentration and constant temperature will be indqiendent of the monomer concentration and reactor type. However, the correct value of the concentration has to be used for calculation of kp. 

Farinha, J.P.S. et al. (1996) Latex film formation probed by norrradiative energy transfer Effect of grafted and free poly (ethylene oxide) on a poly(n-butyl methacrylate) latex. J. Phys. Chem.,... 

The primary initial thermal process is a four-center molecular elimination of water, although the C—C and C—O bond fissions cannot be entirely neglected at high temperatures. With only three heavy atoms in ethanol, pressure effects on the rate constants are significant under many conditions. In 2004, Li et al. provided parameterized pressure-dependent rate constants for the first two channels, and Tsang reported a detailed analysis of energy transfer effects and provided assessments for all three of the above channels. Updated combustion models validated for various conditions are given by Li et al., Saxena and Williams, Haas et al., Leplat et al., Lee et al., and Metcalf... 

Tsang W. Energy transfer effects during the multichannel decomposition of ethanol. Int J Chem Kinet. August 2004 36 456-465. 

A modulation of the fluorescent signal could also be due to inner niter effect and energy transfer effect, both of which require the fluorescent spectrum to overlap with the absorption spectrum of the absorber. The iimer filter effect involves the absorption of the excitation and/or emission light by the quencher. In the energy transfer effect, the fluorescent molecule transfers its excited-state energy to an absorber which dissipates this energy through radiationless transition processes. 

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