Title: Thermal acceleration of ozone interaction with graphite and other organocarbons

A co-rotating interaction region (CIR) forms in a stellar wind when a fast stream from a rotating star overtakes a slow stream. The CIR's were studied in detail in the solar wind over the past decade primarily because they are efficient sources of particle acceleration. Here, CIR's in OB star winds are used to explain two properties of such winds: deposition of non-radiative energy in the wind far from the stellar surfaces and acceleration of non-thermal particles.

Selected newer literature from 1986 through 1988 on the vegetation and health effects resulting from exposure to ozone is reviewed and summarized for the purpose of providing the Agency with information useful in identifying new data that may be relevant for developing primary and secondary National Ambient Air Quality Standards for Ozone.

Since completion of the 1986 Air Quality Criteria Document for Ozone, additional information has become available that warrants consideration by U.S. Environmental Protection Agency (U.S. EPA) in its review of the National Ambient Air Quality Standards (NAAQS) for ozone. The summary reviews and evaluates selected literature published from 1986 through early 1989 on the vegetation and health effects resulting from exposure to ozone. Emphasis has been placed on evaluation of key human health effects literature and other data most pertinent to determination by U.S. EPA of the appropriate level and form of the primary NAAQs and the appropriate form ofmore » the secondary NAAQs.« less

Molten sodium attacks artificial graphites, causing dilation and, under some conditions, decrepitation. Because of the anisotropy of extruded grsphite, dilation perpendicular to the extrusion axis is slightly greater than parallel to the extension axis. At 600 to 1OOO deg F, sodium is initially nonwetting to graphite, but becomes wetting in a matter of minutes. The liqiud soaks into the pores of the graphite through chemisorption and intergranular penetration; in- terlamellar compounds or complexes may also be formed. Coatings and coating techniques were investigated for the protection of graphite from attack by molten sodium. The coatings examined included chromium, nickel, zirconium,more » zirconium carbide, tungsten carbide, silicon carbide, silicon nitride, and molybdenum disilicide. None of the coatings, tested by soaking in static sodium at 1OOO deg F, gave satisfactory protection. Failure in all cases resulted from continuous porosity or cracks in the coating material. (auth)« less