Measurements of secondary electron emission coefficient and surface work function ~1 are reported for polyacrylonitrile (PAN) and polytetrafluoroethylene (PTFE) in the virgin and chemically modified forms. A single pulse method was used for SEE measurements and a retarding field method for estimating the work function. Doping of PTFE with alkali metals (Na and Li) and pyrolysis of PAN at 300 "C led to an increase in the surface conductivity. The processing of the surface effectively increased the SEE yield in these polymers. Electrical conductivity and XPS results were used to explain the chemical structures of modified polymers.
We study equations of a non-gauge vector field in a spherically symmetric static metric. The constant vector field with a scale arrangement of components, the temporal component about the Planck mass m Pl and the radial component about M suppressed with respect to the Planck mass, serves as a source of metric reproducing flat rotation curves in dark halos of spiral galaxies, so that the velocity of rotation v 0 is determined by the hierarchy of scales: √ 2v 2 0 = M/m Pl , and M ∼ 10 12 GeV. A natural estimate of Milgrom's acceleration about the Hubble rate is obtained. PACS numbers: 04.40.−b, 95.35.+d, 04.40.Nr, 98.62.Gq 1 An example of an alternative description due to a modification of gravity is given in [15].
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