Brush discharge plastics. The ability of an electrical discharge to cause an explosion in flammable atmospheres is measured by the "effective energy" of the discharge. The effective energy of brush discharges is 10-20 mJ, much larger than that of corona discharges 0.1 mJ. Therefore, brush discharges are considered an explosion hazard, while corona discharges are not. Brush discharges can occur from charged insulating plastics (for example polythene) to a conductor. Brush discharge A brush discharge is an electrical disruptive discharge similar to a corona discharge that takes place at an electrode with a high voltage applied to it, embedded in a nonconducting
Word square between the two. The Sator Square is a famous word square in Latin. Its canonical form reads as follows. In addition to satisfying the basic properties of word squares, the Sator Square spread widely due to several other attributes: it is palindromic; it can be read as a sentence of obscure meaning; and additional meaning such as reference to the Christian Paternoster prayer can be derived from its letters. However, the word "Arepo" appears nowhere else in Latin literature; most of those who have studied the Sator Square agree that it is to be taken as a proper name, either