CONTIN analysis

The inset shows a unimodal distribution of relaxation times r = I 1 obtained by a CONTIN analysis. Besides CONTIN there is a number of alternative techniques [51] for the determination of the distribution from the correlation function. Detailed discussions of this topic have been given by Stock and Ray [52] and by Stepanek [50]. 

Fig. 14 shows the amplitudes of the two components and of the whole concentration signal as a function of xp. Both modes could be resolved for all exposure times, and the insert of Fig. 14 shows, as an example, the rate distribution for xp = 0.2 s as obtained from a CONTIN analysis. The solid lines are the parameter-free predictions according to Eq. (32). 

Fig. 16. Differential (c(M)) and cumulative (I(M)) molar mass distribution as calculated from for Tp = 0.025 s and fp = 1.5 s. The inserts are the rate distributions as obtained from a CONTIN analysis. From Ref. [37]...

Fig. 33 shows in a more quantitative analysis the rate distributions as obtained by a CONTIN analysis of the PCS and the stochastic TDFRS measurement. 

Fig. 36. Differential and integral rate distributions as obtained from a CONTIN analysis of the measurements in Fig. 35. The central peak is enhanced in the filtered stochastic TDFRS experiment...

FIG. 5 PSDs generated from NNLS and CONTIN analysis of the ACF data shown in Fig. 4 for Stober [6X silica particles. For comparison, the bar graph is the nuinber-weighted TEM histogram of particle sizes [711. 

Bodycomb J, Hara M. Light scattering study of ionomers in solutions. 5. CONTIN analysis of dynamic scattering data from sulfonated polystyrene ionomer in a polar solvent (dimethylformamide). Macromolecules 1995 28 8190-8196. 

Dynamic light scattering experiments were conducted for sulfonated PS ionomers in DMF [87]. CONTIN analysis of the decay rate generally indicates the existence of two decay modes. Both modes have a q2 dependence and therefore are diffusive processes. This is similar to that observed for salt-free polyelectrolytes in aqueous solution [76-79],... 

When using routine LT9.0, a partial improvement occurs by assuming that the o-Ps lifetime xs shows a distribution. The artifacts are removed more or less completely when the distribution in the e+ lifetime X2 is also taken into account. As mentioned, we have confirmed these conclusions by LT9.0 analysis of simulated spectra. The allowance of a distribution in x uncouples the t2 analyzed from T3, and the allowance of a distribution in X2 uncouples ri from t2. The reason that LT9.0 avoids artifacts also observed in continuous Melt and Contin analysis lies in reduction in the degree of freedom by assuming a number of different lifetime channels in LT9.0. Moreover, because the lifetime analysis is less sensitive to the particular shape of the distributions, the assumed lognormal k function usually seems to describe the real situation sufficiently well. These are the reasons that we prefer to use the routine LT9.0 for the analysis of positron lifetime spectra. 

Mao, R., J. Tang, and B. G. Swanson. 2000. Relaxation time spectrum of hydrogels by CONTIN analysis. Journal ofEood Science 65, no. 3 374—381. 

Figure 3.19. CONTIN analysis results for the autocorrelation functions shown in Fig. 3.18. The distribution of the apparent diameter is plotted as a function of in a logarithmic scale.

Figure 12.12 Distributionindiffusionco Bdentsforanaroiiiaticterpolyesterinaiiiixed solvent of trifluoroaoetk add and dkhlorometiiaiie obtained by contin analysis of quasi elastic light scattering data...

In dynamic LLS, the Laplace inversion of each measured intensity-intensity time correlation function G q, t) in the self-beating mode can result in a line-width distribution G(L). G(7) can be converted into a translational diffusion coefficient distribution G(D) or further a hydrodynamic radius distribution /(Rh) via the Stokes-Einstein equation, Rh = (kBTI6nrio)/D, where kB, T and qo are the Boltzmann constant, the absolute temperature and the solvent viscosity, respectively. The time correlation functions were analyzed by both the cumulants and CONTIN analysis. 

Fig. 2(b). Plot of the characteristic linewidth distribution G(T) vs. f from the CONTIN analysis for LPS80. Only one narrow peak is obtained. 

By using the CONTIN analysis, we obtained one characteristic linewidth with a small variance for the two narrow MWD PS samples and two linewidths for the broad MWD PS sample. Figures 2b, 3b and 4b show the characteristic linewidth distribution of LPS80, LPS100 and LPS230 binary PS/TOL solutions, respectively. Numerical values of the data analysis of binary PS/TOL solutions are listed in Table 5. A is the integrated area of the observed peak for the characteristic linewidth distribution from the CONTIN method of analysis. 

Table 5. CONTIN analysis results of PS/TOL binary solutions at 25 C... 

Table 6. CONTIN analysis results of PS1/PS2/T0L ternary solutions at 25°C...

Fig. 5(b). Plot of G(F) vs. F from the CONTIN analysis for LPS82. There are two peaks in which the F for the fast mode is almost the same as that of the LPS80 binary solution. The magnitude of the slow mode A2 is 14%. 

In the case of star polymers as test chains, the more the number of arms, the smaller the possibility for stars to be detached from the matrix once they are attached to the matrix over much longer periods. Even though star test chains are smaller, their motions are still hindered by other entangled polymer coils. If most star test chains participate in the entanglement, the amount of "free" stars is too small to be detected. So the CONTIN analysis did not show two modes for LPS84, but we do not want to deny the possible existence of self-diffusion of star test chains because I I of LPS84 evidently deviated from the single exponential decay. 

Fig. 6.8 Zimm plot based on SLS measurements on M0154 aqueous solutions (three different concentrations were measured), yielding an average Rg of 45.2 nm (inset) CONTIN analysis of DLS data (scattering angle 60°) on the same solution, showing an average value of 44-45 nm. For spherical particles, = Rg suggests that all the mass is distributed on the surface of the sphere, that is, a vesicle structure...

Fig. 20.5. Distribution of decay constant obtained by dynamic light scattering using CONTIN analysis for ionomer (0.76 mol /o ion content) as well as PS in Toluene...

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