Charles F. Gallo

Corona-A Brief Status Report

Relevant to many practical applications [1] including xerography [2]-[9], the various forms of gas discharge which can occur in asymmetrical gaps (for example, needle-to-plane geometry) have been briefly summarized in this status report. Due to its engineering importance, emphasis have been placed upon corona in atmospheric air, particularly l) the positive glow corona, especially the emerging controversy concerning the role of negative ions, and 2) the negative Trichel pulse corona, particularly the latest research in this field including the transition to sparking. Although a considerable body of knowledge is available, controversies remain, and there are many interesting things left to be done.

Parametric Study of Ozone Generation by Coronas

It is shown that previous data on the ozone generation rate by dc coronas can be described by a simple model employing the following concepts. 1) The ozone generation rate is proportional to the electrical power dissipated in the ionization sheath surrounding the wire. 2) The voltage drop across the ionization sheath is proportional to the corona threshold voltage and independent of both the applied voltage and the corona current.

Electrification by Contact Charge Exchange: A Literature Survey of Microscopic Models

There is a wide assortment of complicated electrical charge-exchange phenomena that can occur when two materials are simply brought into contact and then separated. The relevant literature is extensive and complicated. Thus the literature on microscopic models of contact electrification is surveyed, and the essential features are systematically condensed so that comparisons can be readily made between the various theoretical models. Particular attention has been focused on controversies and some areas in need of investigation.