Weathering general aspects

With the latter background to the problem and the framework for chemical weathering in mind, the author would like to outline the plan that will be followed for the remainder of this paper (1) the study area will be described from the standpoint of hydrogeologic environment (geology, topography and climate) and the hydrodynamics and general aspects of the groundwater... 

Nuclear PSAs tend to accept a set of initiators such as the WASH-1400 set or the EPRI set and proceed with little introspection as to completeness of the set for a specific plant. A well-known omission is sabotage. In general, earthquake and fire is treated poorly tornado is usually not addressed nor are other aspects of adverse weather such as freezing and ice storms which may have common cause potential. The record has not been too good. After the Browns Ferry fire, it was claimed that such was addressed in WASH-1400. If so, attention was only brought after the fact. The TMI-2 sequence was not addressed in the PSAs to an extent that action was taken to prevent it. 

This general area has been reviewed in depth by Briggs (1990), who gives an extended bibliography of the application of XPS to a number of aspects, including plasma treatment, photooxidation and weathering, biomedical polymers and polymer-metal interactions. 

The appearance of wood exposed outdoors without protective paint, stain, or treatment changes markedly in a few months then the wood remains almost unaltered for years (9-11). Color of the wood is affected very early (11,12). Generally, all unprotected woods change in color to a brown. After prolonged weathering, all woods become gray (9). Recent research has been concerned with many aspects of weathering of wood (13-18). 

Dclwiche, C.C., 1958. Weathering of great world soil groups as related to general atmospheric radioactivity. In Waste Treatment and Environmental Aspects of Atomic Energy, 18 551-556. 

There are several other aspects of atmospheric characterization which, if measured, can provide pertinent information related to the performance of materials. Probably the most important and universal is the determination of the TOW, described earlier. ASTM G 84, Practice for Measurement of Time-of-Wetness on Surfaces Exposed to Wetting Conditions as in Atmospheric Corrosion Testing, describes instrumentation and techniques for measuring TOW. This parameter can most easily (and adequately) be estimated from weather bureau records. It is generally accepted that metal atmospheric test specimens are wet when the temperature is above freezing and the relative humidity is above 80 %. There are indications that corrosion can occur under arctic conditions down to 0°F if... 

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