Staircase polymer

Senn, S. M. and Poulikakos, D. 2004. Tree network channels as fluid distributors constructing double-staircase polymer electrolyte fuel cells. / 96(1), 842-852. 

FIGURE 33. (a) View of the core structure of 2D polymer [(CuI)2 p,-/>-TolS (C H2>4STol-/ 2], 18 on the ab plane. H atoms groups are omitted for clarity, (b) Presentation of the inorganic staircase ribbon along the a axis. 

The VCD calculated for this model polymer is shown in Figure 3, and resembles that observed for the decamer sequence d(CG)5, both in overall spectral appearance and signal magnitude (cf. Section 5). Thus, the simplistic "spiral staircase" model appears to be a good starting point for the qualitative interpretation of the experimental data. 

Polymer 139 is another example of a mixed-ligand 1-D polymer. The difference with 137 and 138 is that bromide ions replace the diisocyanides.124 The X-ray structure reveals two Ag-Br distances (2.7431(13) and 2.9453(14) A), and the dimension indicates ionic interactions. The structure also exhibits a staircase geometry as previously and the nonbonding Ag -Ag separations are 3.605(2) and 3.916(2) A for the dmpm- and Br-bridged fragments, respectively. Raman spectra exhibit v(Ag -Ag) of 48 cm-1, giving a weak approximate force constant of 0.03 mdyn A-1. 

Both DNA and RNA are polymers their monomer units are called nucleotides and consist of three parts a phosphate group, a pentose (5-carbon sugar) and a nitrogen-containing base. The DNA molecules vary in size, but they can have as many as 30,000 base pairs, and they are the largest of all natural molecules. We now know that the three-dimensional staicture of DNA is a double helix a form resembling a spiral staircase. The outside handrails are the sugar-phosphate... 

Then came several semisynthetic polymers, which were natural polymers modified in some way. One of the first to attain commercial importance was cellulose nitrate plasticized with camphor, popular around 1885 for stiff collars and cuffs as celluloid, later most notably used in Thomas Edison s motion picture film (11). Cellulose nitrates were also sold as lacquers, used to coat wooden staircases, and so on. The problem was the terrible fire hazard existing with the nitrates, which were later replaced by the acetates. 

Hence, a solid-phase polymers deformation process is realized in fractal space with the dimension, which is equal to structure dimension d. In such space the deformation process can be presented schematically as the devil s staircase [39]. Its horizontal sections correspond to temporal intervals, where deformation is absent. In this case deformation process is described with using of fractal time t, which belongs to the points of Cantor s set [30]. If Euclidean object deformation is considered then time belongs to real numbers set. 

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