vidence for depth-dependent structural changes in freeze/thaw-cycled dry afion® using positron annihilation lifetime spectroscopy (PALS)
نویسندگان
چکیده
The effects of freeze/thaw (F/T) cycling on the structure of dry Nafion® membranes were investigated using positron annihilation lifetime spectroscopy (PALS). The method correlates the lifetime and relative intensity of positrons (anti-electrons) annihilating in the open-volume voids of the membrane with void size and void volume fraction. The results, though still preliminary, show freeze/thaw-induced collapse vailable online 5 February 2009
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