A dry environment largely obviates radiolysis effects. In liquid environments, relatively complex radiolysis reactions can occur, particularly where multiple species are present. Thus, in moderate temperature regimes, elevated temperatures may be useful rather than detrimental for exposures of metal to air. Dry cooling tower technology has demonstrated that in pollution-free moist more ยป environments, metals fare better at temperatures above than below the dewpoint. Areas on the copper surfaces which appear to represent glacial abrasion show minimal corrosion. Copper masses from the Michigan deposits were transported by the Pleistocene glaciers. Approximately five million tonnes were mined from native copper deposits in Michigan. Some meteoritic masses with ages estimated to be 5,000 to 20,000 years have weathered very little, while other masses from the same meteorites are in advanced stages of weathering. The metal meteorites are Fe-base alloys with 5 to 60 wt% Ni and minor amounts of Co, I, and S. The old technology required high-end graphic cards and was. The new technology requires little technical skill and can be very inexpensive. Dry environments, such as tombs, appear to be optimum for metal preservation, but some metals have survived in shipwrecks for over a thousand years. The new technology from Google called Wirecast enables users to cast audio from almost any internet enabled device to their personal computer or laptop, mobile device or television. Gold is clearly the most durable, but many objects fashioned from silver, copper, bronze, iron, lead, and tin have survived for several thousand years. Archaeological and radiochemical dating suggest that human use of metals began in the period 6000 to 7000 BC. This study summarizes the ancient metals, the environments, and factors which appear to have contributed to metal longevity. Metal durability is an important consideration in the multi-barrier nuclear waste storage concept.
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