Decay parameter

For most appHcations, the decay parameters of the radionucHdes of interest ate known with sufficient accuracy for their uncertainties not to be of any concern. Typically this is the case if the uncertainty in the half-life is 0.1% or less and the uncertainty in the y-emission probabiHty is 1% or less. 

Figure 3. Dimensionless heat generation function fg and removal function r vs. dimensionless temperature 6 at different values of a time-decaying parameter i (3)...

Tellinghuisen, J. and Wilkerson, C. W. (1993). Bias and precision in the estimation of exponential decay parameters from sparse data. Anal. Chem. 65, 1240-6. 

Global compartmental analysis can be used to recover association and dissociation rate constants in some specific cases when the lifetimes are much shorter than the lifetimes for the association and dissociation processes. An example is the study for the binding dynamics of 2-naphthol (34, Scheme 14) with / -CD.207 Such an analysis is possible only if the observed lifetimes change with CD concentration and at least one of the decay parameters is known independently, in this case the lifetime of the singlet excited state of 33 (5.3 ns). From the analysis the association and dissociation rate constants, as well as intrinsic decay rate constants and iodide quenching rate constants, were recovered. The association and dissociation rate constants were found to be 2.5 x 109M-1 s 1 and 520 s 1, respectively.207... 

The Debye-Hiickel decay parameter, k, which has units of m is a function of the ionic strength, I, and the permittivity ... 

D. R. James and W. R. Ware, A fallacy m the interpretation of fluorescence decay parameters, Chem. Phys. Lett. 120,455-459 (1985). 

Figure 1.4. Fluorescence decay parameters of 3-(p-hydroxyphenyI)propionic acid as a function of pH. The filled squares indicate the association between the shorter lifetime and its amplitude the open squares that between the longer lifetime and its amplitude. The solid lines running through the relative amplitudes express the theoretical Henderson-Hasselbach relationship for a pK of 4.5. The solid lines connecting the lifetimes represent their average value. (Reprinted from Ref. 38 with the permission of the American Chemical Society.)...

The fluorescence decay parameters of tyrosine and several tyrosine analogues at neutral pH are listed in Table 1.2. Tyrosine zwitterion and analogues with an ionized a-carboxyl group exhibit monoexponential decay kinetics. Conversion of the a-carboxyl group to the corresponding amide results in a fluorescence intensity decay that requires at least a double exponential to fit the data. While not shown in Table 1.2, protonation of the carboxyl group also results in complex decay kinetics.(38)... 

Table 1.2. Fluorescence Decay Parameters for Tyrosine and Tyrosine Analogues...

Fig. 20 Charge carrier mobility in P3HT as a function of the charge carrier concentration. Squares refer to an experiment performed on a field effect transistor while circles refer to experiments done on an electrochemically doped sample. In the latter case the mobility is inferred from the steady state current at a given doping level. Solid and dashed lines have been fitted using the theory of [101]. The fit parameters are the site separation a, the prefactor Vq in the Miller-Abrahams-type hopping rate, the inverse wavefunction decay parameter y and the dielectric constant e. From [101] with permission. Copyright (2005) by the American Institute of Physics...

If it can be shown independently that fcMD 1/r at the prevailing temperature (Section III.A), then a value for rj at infinite dilution may be used to compute fcDM directly from [M]yz in all other cases the evaluation of kDM requires an examination of the fluorescence decay parameters as described in Section II.D below. 

Decay parameter of the rate constant, decay parameter due to electronic contributions, respectively Reorganization energy, internal and solvent contributions, respectively... 

Consider two DNA fragments d-bib2...bm-a and d-bib2—bn a where donor and acceptor are separated by r-stacked bridges of lengths m and n, respectively. The distance dependence of the rate constant is often expressed in terms of an exponential decay parameter /i [5-9] ... 

Decay Parameters (in ns) of Various TPM Dyes in Glycerol at -11.5°C Fitted by a... 

Table II. Second-Harmonic Coefficients ( 33) and Temporal Decay Parameters for Corona-Poled, NPP-Functionalized Poly(p-hydroxystyrene) Films as a Function of Thermal Cross-Linking a...

Figure 3. Time dependence of the second harmonic coefficient, d33, for corona-poled (PS)O-NPP films. A. Simultaneously poled (180°C) and cross-linked with 0.50 equiv. 1,2,7,8-diepoxyoctane/phenol OH B. Poled at 180°C C. Poled at 150°C. The solid lines are least-squares fits to equation 1, yielding the decay parameters in Table II.

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