CHARGE EFFECT IN NUCLEPORE FILTER.

Abstract

Tests performed during long sampling periods with Nuclepore polycarbonate filters have shown that the collection efficiency for aerosols presents a strong time dependence. Significant amounts of electric charge measured on the filter during filtration are believed to play an important role in its efficiency. Here we propose a model for trapping particles which includes electric dipolar effects. A mechanism for migration of particulate is also suggested.