Layer Structures of Composite Membranes for Water Filtration Elucidated by Variable-Energy Positron Annihilation


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Commercial composite membranes for water purification were studied by means of the variable-energy positron annihilation γ-ray technique. The positron incident energy E dependence of R parameter (3γ/2γ ratio) analyzed from positron annihilation γ-ray spectra revealed the layer structure consisting of a dense top layer and a porous substrate for the membranes. Thickness of the dense layer for each membrane was evaluated from the R(E) based on a positron implantation stopping profile.



Edited by:

Jozef Krištiak, Jan Kuriplach and Pradeep K. Pujari




Z. Chen et al., "Layer Structures of Composite Membranes for Water Filtration Elucidated by Variable-Energy Positron Annihilation", Materials Science Forum, Vol. 733, pp. 45-48, 2013

Online since:

November 2012




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