Chain aggregate

Fig. 6 Radius of gyration as a function of particle weight for AX-I in several solvents. The single, non-aggregated chains has = 62000g/mol, determined with the percarbani-lated sample in dioxane [102]...

Worsfold and Bywater 212) have proposed that propagation through non-aggregated chains is kinetically (and not thermodynamically) controlled and yields only the carbanion having the cis conformation this can isomerize to the trans form unless the geometry is locked in by a further act of propagation ... 

Keywords. Asymmetry, Miktoarm stars, Synthesis, Morphology, Aggregation, Chain conformation... 

In this section we examine the solutions of Maxwell s equations for a system with a broad and dispersionless electronic resonance. We show that these conditions result in the appearance of the end-points of the lower and upper polariton branches. These end-points restrict the intervals in which the polariton states have well-defined wavevectors. This consideration is applicable, in particular, to the disordered system of J-aggregates since each J-aggregate chain possesses rather narrow electronic transitions instead of broad dispersion (Fig. 10.3). The disorder present in the system does not influence the following arguments, since for small-cavity photon wavevectors, the system can be treated as effectively homogeneous. 

Rather, four different motifs could be identified (Scheme 13), with none being predominant. This is in contrast to the behaviour of simple monoalcohols that crystallise mainly in two type of 0-H- -O aggregates - chains and rings... 

Restricted hydration and mobile chains Highly dehydrated and aggregated chains... 

In this paper we present a comparative pressure and electric-field tuning hole burning study between PIC monomers and aggregates. It is our goal to gain information on the coherence length of the excitons on the aggregate chains from these comparative experiments. 

Later, Tanaka and Nishinari [7] estimated the structure of the junction zone using the experimental results rqrorted by Domszy et al. [3]. They proposed the model shown in Fig. 1 for the junction zone formed by the aggregation of polymer chains. They also derived parameters that correspond to the number of aggregating chains and the parameter C that corresponds to the number of chemical repeat units forming the crosslink [8, 9]. The parameter s is called junction multiplicity. In this model, gels are formed with crystallites in the junction zone. 

The surface entropy curves As e) for various numbers of aggregating chains shown in Fig. 11.9 resemble the plots for the homopolymers in Fig. 12.3(c). Therefore, we expect that peptide aggregation processes also are hierarchical [266]. 

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