When the Sun becomes more active, this isotope becomes more abundant along with beryllium, another radioactive element.
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Another analysis, also published in the journal Science, looks at the amount of the isotope beryllium-10 in the lunar soil.
Beryllium-10 can be produced in the Sun when highly energetic protons bombard the nuclei of other elements like carbon and oxygen.
Greenpeace wants to see companies eliminate the use of hazardous substances such as polyvinyl chloride, brominated flame retardants, antimony, beryllium, and phthalates.
Because of the ratio of radioactive carbon and beryllium found in the tree rings, researchers could also rule out some other possibilities.
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Beryllium: used as a lightweight component in military equipment and in the aerospace industry. it is used in high-speed aircraft, missiles, space vehicles and communication satellites.
However some others in the scientific community disagree because they do not think that the energy produced would tally with the levels of carbon-14 and beryllium-10 found.
Fusa Miyake discovered Carbon-14 and Beryllium-10 traces in tree rings from the era, which point to a gamma ray burst from a celestial body other than the Sun.
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The ex-Soviet producer of beryllium, a plant called Ulba, was trying to export that metal to the US. The sole US producer (in any volume at least) was Brush Wellman.
Reducing the number of beryllium ions in the trap will boost the sensitivity further, the researchers say, and, with a single beryllium ion, it should be possible to measure a single yoctonewton.
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The researchers say their work provides strong evidence that the beryllium and, therefore, other constituents produced in the Sun's atmosphere are being ejected shortly after they are produced - to hit the Moon.
But, a detailed analysis of the lunar samples by Kuni Nishiizumi, from the University of California at Berkeley, and Marc Caffee, from Purdue University, suggests that far more beryllium exists in the soil than can be accounted for by cosmic-ray delivery alone.
Peak neodymium is the latest threat to green energy, while doubt emerges over the security of many other element groups including the rare earths, the platinum group metals, and elements such as antimony, beryllium, gallium, germanium, graphite, indium, magnesium, niobium, tantalum and tungsten.
Throw in the Price-Anderson Act, the huge liability of working with radiation, beryllium and asbestos, the extensive training requirements, safety issues, QA audit requirements, and the host of accountants, lawyers and HR people needed to be a prime to DOE, and you can imagine that few small businesses could even submit a proposal to be a prime contractor to the Department of Energy.
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