Diluge
发表于 2025-4-1 05:04:46
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vitreous-humor
发表于 2025-4-1 08:21:30
https://doi.org/10.1007/978-3-663-11933-3imately 90 elements found in the earth’s crust, a mere nine (aluminum, calcium, iron, magnesium, oxygen, potassium, silicon, sodium, and titanium) account for over 99% by weight. The other 80 or so elements, which together total less than 0.14%, are known as the trace elements and play an important
绑架
发表于 2025-4-1 11:35:26
https://doi.org/10.1007/978-3-531-91196-0 that radiation is continuously released from uranium-containing minerals, just a few months after Roentgen’s discovery of X rays in November, 1895. But only within the last 30 years has concern over man-made radioactivity arisen, as a result of the discovery of fission and its use in weapons that r