Electrification

It has long been known that the form of a curved surface of mercury in contact with an electrolyte solution depends on its state of electrification [108, 109], and the earliest comprehensive investigation of the electrocapillary effect was made by Lippmann in 1875 [110]. A sketch of his apparatus is shown in Fig. V-10. 

Each segment of the insulated wire and cable industry has its own set of standards, and cables are built to conform to specifications provided by a large variety of technical associations such as The Institute of Electrical Electronic Engineers (IEEE), The Insulated Cable Engineers Association, (ICEA), National Electrical Manufacturers Association (NEMA), Underwriters Laboratories (UL), Rural Electrification Administration of the U.S. Department of Agriculture (REA), Association of Edison Illumination Companies (AEIC), MiUtary Specifications of the Department of Defense (MIL), American Society for Testing and Materials (ASTM), National Electrical Code (NEC), etc. 

Highway Electrification and Automation Development Program, TR-093-003, H. R. Ross Industries, Inc., Los Angeles, Feb. 10, 1993. 

D. Lovejoy, "Electrification of Rural Areas by Solar PV," International Workshop on Mass Production ofPhotovoltaics Commercialicyation andPoliy Options,... 

B. Chabot, Pural Electrification Guidebook for Asia and the Pacific, UN-ESCAP, Bangkok, 1992. 

Agriculture Department USDA agriculture, animal and plant health inspection, forest service, food safety. Rural Electrification Administration, soil conservation service... 

Electrification is the process of producing an electric charge on an object. If the charge is confined to the object it is said to be electrostatic. The term static electricity refers to accumulated, immobile, electrical charges in contrast to charges in rapid flow, which is the subject of electrodynamics. 

Static electrification may not be a property of the basic stmcture, but of a new surface formed by a monomolecular layer of water (82). All textile fibers at a relative humidity, at which a continuous monomolecular layer is formed, actually do have the same charge density. This is attributed to the absence of ionic transport which caimot occur in a monomolecular layer. At higher moisture levels than required to form a monomolecular layer, ionic conductivity can occur because of excess water molecules and by hydration of the ions. At very low moisture-regain levels, all materials acquire the same charge (83). 

W. R, Harper, Contact and Frictional Electrification, Oxford University Press, Oxford, UK, 1967. 

Particles carrying charges of opposite polarity due to contact electrification will be attracted to opposite electrodes when passing through an electric field and thus can be separated from each other. 

Types The primaiy cause of electrostatic charging is contact electrification, which takes place when two different materials are brought into contact and separated. Other causes include induction charging, the formation of sprays, and impingement of charged mist on an ungrounded conductor. 

Contact Electrification This form of charging involves the contact and separation of solid-sohd, sohd-hquid, or hquid-liqmd surfaces. Pure gases do not cause charging unless they cany droplets or dust particles. 

To determine the level of electrification on an insulating surface, an elec tric field meter should always be used. There is a direct relationship between the charge density on the surface of an insulator and the elec tric field intensity at the surface. Measurements should be made at locations where the insulating surface is several inches away from other insulating or conduc tive surfaces. The area of the measured surface should be large, compared to the field of view of the meter. In locations where a flammable vapor-air mixture has an MIE greater than 0. 2 mj, field intensities of 500 kV/m or more should be considered unsafe. 

Deliberate stray current drainage was installed at a subrectifier in Germany as early as 1895 during the electrification of the Aachen tramway. The effective protection extended over a relatively small field since the comparatively large resistance of the pipe Joints did not permit a greater extension of protection. 

Hughes, T. P. (1983). Networks of Power Electrification in Western Society, 1880-1930. Baltimore Johns Hopkms University Press. 

GE, Baltimore First major railroad electrification Co. locomotive for freight service, and... 

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