There are strong reasons from dc and pulsed-current measurements, and fromthermal conductivity results, for thinking that narrow channels through filmsof oxidised atatic polypropylene (OAPP) are superconducting at roomtemperature. It is thought that the conducting channels, with diameters lessthan or of the order of a micrometre, are composed of smaller nanofilaments,with diameters of the order of a nanometre. In the present paper a possibleexplanation is given of measurements which show that the average resistance ofnon-superconducting channels through films increases with film thickness moreslowly than linearly. This result is interpreted in terms of how the Bosecondensation temperatures of bosons in arrays of nanofilaments depend on thelength and numbers of filaments, and examples are given of parameters of thearrays which could explain the data. The dispersion for the bosons is assumedto consist of a sum of linear and quadratic terms, which is an approximate typeof dispersion reported for Cooper pairs. In order to fit the data with themodel used, it is necessary to suppose that values of superconducting Tc forchannels composed of large numbers of filaments are only slightly above roomtemperature. It is argued that larger Tc's reported in 1989 when currents of0.5 A are passed through channels may arise because (a) currents concentrate ina subchannel of smaller width than the original channel, and (b)current-current interactions draw the filaments of the subchannel sufficientlyclose together to increase the transverse bandwidth and Tc in the model by therequired amount.
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